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Fix DKIM information leakage
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11 #define PENDING 256
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
14
15 #define DELIVER_BUFFER_SIZE 4096
16
17
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
22
23 optionlist smtp_transport_options[] = {
24 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
25 (void *)offsetof(transport_instance, expand_multi_domain) },
26 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
27 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
28
29 { "address_retry_include_sender", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
31 { "allow_localhost", opt_bool,
32 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
33 { "authenticated_sender", opt_stringptr,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
35 { "authenticated_sender_force", opt_bool,
36 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
37 { "command_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, command_timeout) },
39 { "connect_timeout", opt_time,
40 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
41 { "connection_max_messages", opt_int | opt_public,
42 (void *)offsetof(transport_instance, connection_max_messages) },
43 { "data_timeout", opt_time,
44 (void *)offsetof(smtp_transport_options_block, data_timeout) },
45 { "delay_after_cutoff", opt_bool,
46 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
47 #ifndef DISABLE_DKIM
48 { "dkim_canon", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
50 { "dkim_domain", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
52 { "dkim_private_key", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
54 { "dkim_selector", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
56 { "dkim_sign_headers", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
58 { "dkim_strict", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
60 #endif
61 { "dns_qualify_single", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
63 { "dns_search_parents", opt_bool,
64 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
65 { "dnssec_request_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
67 { "dnssec_require_domains", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
69 { "dscp", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, dscp) },
71 { "fallback_hosts", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
73 { "final_timeout", opt_time,
74 (void *)offsetof(smtp_transport_options_block, final_timeout) },
75 { "gethostbyname", opt_bool,
76 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
85 #ifdef SUPPORT_TLS
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
88 #endif
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
93 #ifdef SUPPORT_TLS
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
96 #endif
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
102 { "hosts_request_ocsp", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
104 #endif
105 { "hosts_require_auth", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
107 #ifdef SUPPORT_TLS
108 # ifdef EXPERIMENTAL_DANE
109 { "hosts_require_dane", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
111 # endif
112 # ifndef DISABLE_OCSP
113 { "hosts_require_ocsp", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
115 # endif
116 { "hosts_require_tls", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
118 #endif
119 { "hosts_try_auth", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
121 { "hosts_try_chunking", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
123 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
124 { "hosts_try_dane", opt_stringptr,
125 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
126 #endif
127 { "hosts_try_fastopen", opt_stringptr,
128 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
129 #ifndef DISABLE_PRDR
130 { "hosts_try_prdr", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
132 #endif
133 #ifdef SUPPORT_TLS
134 { "hosts_verify_avoid_tls", opt_stringptr,
135 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
136 #endif
137 { "interface", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, interface) },
139 { "keepalive", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, keepalive) },
141 { "lmtp_ignore_quota", opt_bool,
142 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
143 { "max_rcpt", opt_int | opt_public,
144 (void *)offsetof(transport_instance, max_addresses) },
145 { "multi_domain", opt_expand_bool | opt_public,
146 (void *)offsetof(transport_instance, multi_domain) },
147 { "port", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, port) },
149 { "protocol", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, protocol) },
151 { "retry_include_ip_address", opt_expand_bool,
152 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
153 { "serialize_hosts", opt_stringptr,
154 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
155 { "size_addition", opt_int,
156 (void *)offsetof(smtp_transport_options_block, size_addition) }
157 #ifdef SUPPORT_SOCKS
158 ,{ "socks_proxy", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
160 #endif
161 #ifdef SUPPORT_TLS
162 ,{ "tls_certificate", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
164 { "tls_crl", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_crl) },
166 { "tls_dh_min_bits", opt_int,
167 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
168 { "tls_privatekey", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
170 { "tls_require_ciphers", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
172 { "tls_sni", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_sni) },
174 { "tls_tempfail_tryclear", opt_bool,
175 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
176 { "tls_try_verify_hosts", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
178 { "tls_verify_cert_hostnames", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
180 { "tls_verify_certificates", opt_stringptr,
181 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
182 { "tls_verify_hosts", opt_stringptr,
183 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
184 #endif
185 };
186
187 /* Size of the options list. An extern variable has to be used so that its
188 address can appear in the tables drtables.c. */
189
190 int smtp_transport_options_count =
191 sizeof(smtp_transport_options)/sizeof(optionlist);
192
193 /* Default private options block for the smtp transport. */
194
195 smtp_transport_options_block smtp_transport_option_defaults = {
196 NULL, /* hosts */
197 NULL, /* fallback_hosts */
198 NULL, /* hostlist */
199 NULL, /* fallback_hostlist */
200 NULL, /* authenticated_sender */
201 US"$primary_hostname", /* helo_data */
202 NULL, /* interface */
203 NULL, /* port */
204 US"smtp", /* protocol */
205 NULL, /* DSCP */
206 NULL, /* serialize_hosts */
207 NULL, /* hosts_try_auth */
208 NULL, /* hosts_require_auth */
209 US"*", /* hosts_try_chunking */
210 #ifdef EXPERIMENTAL_DANE
211 NULL, /* hosts_try_dane */
212 NULL, /* hosts_require_dane */
213 #endif
214 NULL, /* hosts_try_fastopen */
215 #ifndef DISABLE_PRDR
216 US"*", /* hosts_try_prdr */
217 #endif
218 #ifndef DISABLE_OCSP
219 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
220 NULL, /* hosts_require_ocsp */
221 #endif
222 NULL, /* hosts_require_tls */
223 NULL, /* hosts_avoid_tls */
224 NULL, /* hosts_verify_avoid_tls */
225 NULL, /* hosts_avoid_pipelining */
226 NULL, /* hosts_avoid_esmtp */
227 NULL, /* hosts_nopass_tls */
228 5*60, /* command_timeout */
229 5*60, /* connect_timeout; shorter system default overrides */
230 5*60, /* data timeout */
231 10*60, /* final timeout */
232 1024, /* size_addition */
233 5, /* hosts_max_try */
234 50, /* hosts_max_try_hardlimit */
235 TRUE, /* address_retry_include_sender */
236 FALSE, /* allow_localhost */
237 FALSE, /* authenticated_sender_force */
238 FALSE, /* gethostbyname */
239 TRUE, /* dns_qualify_single */
240 FALSE, /* dns_search_parents */
241 { NULL, NULL }, /* dnssec_domains {request,require} */
242 TRUE, /* delay_after_cutoff */
243 FALSE, /* hosts_override */
244 FALSE, /* hosts_randomize */
245 TRUE, /* keepalive */
246 FALSE, /* lmtp_ignore_quota */
247 NULL, /* expand_retry_include_ip_address */
248 TRUE /* retry_include_ip_address */
249 #ifdef SUPPORT_SOCKS
250 ,NULL /* socks_proxy */
251 #endif
252 #ifdef SUPPORT_TLS
253 ,NULL, /* tls_certificate */
254 NULL, /* tls_crl */
255 NULL, /* tls_privatekey */
256 NULL, /* tls_require_ciphers */
257 NULL, /* tls_sni */
258 US"system", /* tls_verify_certificates */
259 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
260 /* tls_dh_min_bits */
261 TRUE, /* tls_tempfail_tryclear */
262 NULL, /* tls_verify_hosts */
263 US"*", /* tls_try_verify_hosts */
264 US"*" /* tls_verify_cert_hostnames */
265 #endif
266 #ifndef DISABLE_DKIM
267 , {NULL, /* dkim_canon */
268 NULL, /* dkim_domain */
269 NULL, /* dkim_private_key */
270 NULL, /* dkim_selector */
271 NULL, /* dkim_sign_headers */
272 NULL, /* dkim_strict */
273 FALSE} /* dot_stuffed */
274 #endif
275 };
276
277 /* some DSN flags for use later */
278
279 static int rf_list[] = {rf_notify_never, rf_notify_success,
280 rf_notify_failure, rf_notify_delay };
281
282 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
283
284
285
286 /* Local statics */
287
288 static uschar *smtp_command; /* Points to last cmd for error messages */
289 static uschar *mail_command; /* Points to MAIL cmd for error messages */
290 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
291 static BOOL update_waiting; /* TRUE to update the "wait" database */
292 static BOOL pipelining_active; /* current transaction is in pipe mode */
293
294
295 /*************************************************
296 * Setup entry point *
297 *************************************************/
298
299 /* This function is called when the transport is about to be used,
300 but before running it in a sub-process. It is used for two things:
301
302 (1) To set the fallback host list in addresses, when delivering.
303 (2) To pass back the interface, port, protocol, and other options, for use
304 during callout verification.
305
306 Arguments:
307 tblock pointer to the transport instance block
308 addrlist list of addresses about to be transported
309 tf if not NULL, pointer to block in which to return options
310 uid the uid that will be set (not used)
311 gid the gid that will be set (not used)
312 errmsg place for error message (not used)
313
314 Returns: OK always (FAIL, DEFER not used)
315 */
316
317 static int
318 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
319 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
320 {
321 smtp_transport_options_block *ob =
322 (smtp_transport_options_block *)(tblock->options_block);
323
324 errmsg = errmsg; /* Keep picky compilers happy */
325 uid = uid;
326 gid = gid;
327
328 /* Pass back options if required. This interface is getting very messy. */
329
330 if (tf != NULL)
331 {
332 tf->interface = ob->interface;
333 tf->port = ob->port;
334 tf->protocol = ob->protocol;
335 tf->hosts = ob->hosts;
336 tf->hosts_override = ob->hosts_override;
337 tf->hosts_randomize = ob->hosts_randomize;
338 tf->gethostbyname = ob->gethostbyname;
339 tf->qualify_single = ob->dns_qualify_single;
340 tf->search_parents = ob->dns_search_parents;
341 tf->helo_data = ob->helo_data;
342 }
343
344 /* Set the fallback host list for all the addresses that don't have fallback
345 host lists, provided that the local host wasn't present in the original host
346 list. */
347
348 if (!testflag(addrlist, af_local_host_removed))
349 {
350 for (; addrlist != NULL; addrlist = addrlist->next)
351 if (addrlist->fallback_hosts == NULL)
352 addrlist->fallback_hosts = ob->fallback_hostlist;
353 }
354
355 return OK;
356 }
357
358
359
360 /*************************************************
361 * Initialization entry point *
362 *************************************************/
363
364 /* Called for each instance, after its options have been read, to
365 enable consistency checks to be done, or anything else that needs
366 to be set up.
367
368 Argument: pointer to the transport instance block
369 Returns: nothing
370 */
371
372 void
373 smtp_transport_init(transport_instance *tblock)
374 {
375 smtp_transport_options_block *ob =
376 (smtp_transport_options_block *)(tblock->options_block);
377
378 /* Retry_use_local_part defaults FALSE if unset */
379
380 if (tblock->retry_use_local_part == TRUE_UNSET)
381 tblock->retry_use_local_part = FALSE;
382
383 /* Set the default port according to the protocol */
384
385 if (ob->port == NULL)
386 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
387 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
388
389 /* Set up the setup entry point, to be called before subprocesses for this
390 transport. */
391
392 tblock->setup = smtp_transport_setup;
393
394 /* Complain if any of the timeouts are zero. */
395
396 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
397 ob->final_timeout <= 0)
398 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
399 "command, data, or final timeout value is zero for %s transport",
400 tblock->name);
401
402 /* If hosts_override is set and there are local hosts, set the global
403 flag that stops verify from showing router hosts. */
404
405 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
406
407 /* If there are any fallback hosts listed, build a chain of host items
408 for them, but do not do any lookups at this time. */
409
410 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
411 }
412
413
414
415
416
417 /*************************************************
418 * Set delivery info into all active addresses *
419 *************************************************/
420
421 /* Only addresses whose status is >= PENDING are relevant. A lesser
422 status means that an address is not currently being processed.
423
424 Arguments:
425 addrlist points to a chain of addresses
426 errno_value to put in each address's errno field
427 msg to put in each address's message field
428 rc to put in each address's transport_return field
429 pass_message if TRUE, set the "pass message" flag in the address
430 host if set, mark addrs as having used this host
431 smtp_greeting from peer
432 helo_response from peer
433
434 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
435 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
436 this particular type of timeout.
437
438 Returns: nothing
439 */
440
441 static void
442 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
443 BOOL pass_message, host_item * host
444 #ifdef EXPERIMENTAL_DSN_INFO
445 , const uschar * smtp_greeting, const uschar * helo_response
446 #endif
447 )
448 {
449 address_item *addr;
450 int orvalue = 0;
451 if (errno_value == ERRNO_CONNECTTIMEOUT)
452 {
453 errno_value = ETIMEDOUT;
454 orvalue = RTEF_CTOUT;
455 }
456 for (addr = addrlist; addr; addr = addr->next)
457 if (addr->transport_return >= PENDING)
458 {
459 addr->basic_errno = errno_value;
460 addr->more_errno |= orvalue;
461 if (msg != NULL)
462 {
463 addr->message = msg;
464 if (pass_message) setflag(addr, af_pass_message);
465 }
466 addr->transport_return = rc;
467 if (host)
468 {
469 addr->host_used = host;
470 #ifdef EXPERIMENTAL_DSN_INFO
471 if (smtp_greeting)
472 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
473 addr->smtp_greeting = smtp_greeting;
474
475 if (helo_response)
476 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
477 addr->helo_response = helo_response;
478 #endif
479 }
480 }
481 }
482
483 static void
484 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
485 BOOL pass_message)
486 {
487 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
488 #ifdef EXPERIMENTAL_DSN_INFO
489 , NULL, NULL
490 #endif
491 );
492 }
493
494
495 /*************************************************
496 * Check an SMTP response *
497 *************************************************/
498
499 /* This function is given an errno code and the SMTP response buffer
500 to analyse, together with the host identification for generating messages. It
501 sets an appropriate message and puts the first digit of the response code into
502 the yield variable. If no response was actually read, a suitable digit is
503 chosen.
504
505 Arguments:
506 host the current host, to get its name for messages
507 errno_value pointer to the errno value
508 more_errno from the top address for use with ERRNO_FILTER_FAIL
509 buffer the SMTP response buffer
510 yield where to put a one-digit SMTP response code
511 message where to put an errror message
512 pass_message set TRUE if message is an SMTP response
513
514 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
515 */
516
517 static BOOL
518 check_response(host_item *host, int *errno_value, int more_errno,
519 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
520 {
521 uschar * pl = pipelining_active ? US"pipelined " : US"";
522
523 *yield = '4'; /* Default setting is to give a temporary error */
524
525 /* Handle response timeout */
526
527 if (*errno_value == ETIMEDOUT)
528 {
529 *message = US string_sprintf("SMTP timeout after %s%s",
530 pl, smtp_command);
531 if (transport_count > 0)
532 *message = US string_sprintf("%s (%d bytes written)", *message,
533 transport_count);
534 return FALSE;
535 }
536
537 /* Handle malformed SMTP response */
538
539 if (*errno_value == ERRNO_SMTPFORMAT)
540 {
541 const uschar *malfresp = string_printing(buffer);
542 while (isspace(*malfresp)) malfresp++;
543 *message = *malfresp == 0
544 ? string_sprintf("Malformed SMTP reply (an empty line) "
545 "in response to %s%s", pl, smtp_command)
546 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
547 pl, smtp_command, malfresp);
548 return FALSE;
549 }
550
551 /* Handle a failed filter process error; can't send QUIT as we mustn't
552 end the DATA. */
553
554 if (*errno_value == ERRNO_FILTER_FAIL)
555 {
556 *message = US string_sprintf("transport filter process failed (%d)%s",
557 more_errno,
558 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
559 return FALSE;
560 }
561
562 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
563 end the DATA. */
564
565 if (*errno_value == ERRNO_CHHEADER_FAIL)
566 {
567 *message =
568 US string_sprintf("failed to expand headers_add or headers_remove: %s",
569 expand_string_message);
570 return FALSE;
571 }
572
573 /* Handle failure to write a complete data block */
574
575 if (*errno_value == ERRNO_WRITEINCOMPLETE)
576 {
577 *message = US string_sprintf("failed to write a data block");
578 return FALSE;
579 }
580
581 #ifdef SUPPORT_I18N
582 /* Handle lack of advertised SMTPUTF8, for international message */
583 if (*errno_value == ERRNO_UTF8_FWD)
584 {
585 *message = US string_sprintf("utf8 support required but not offered for forwarding");
586 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
587 return TRUE;
588 }
589 #endif
590
591 /* Handle error responses from the remote mailer. */
592
593 if (buffer[0] != 0)
594 {
595 const uschar *s = string_printing(buffer);
596 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
597 "%s", pl, smtp_command, s);
598 *pass_message = TRUE;
599 *yield = buffer[0];
600 return TRUE;
601 }
602
603 /* No data was read. If there is no errno, this must be the EOF (i.e.
604 connection closed) case, which causes deferral. An explicit connection reset
605 error has the same effect. Otherwise, put the host's identity in the message,
606 leaving the errno value to be interpreted as well. In all cases, we have to
607 assume the connection is now dead. */
608
609 if (*errno_value == 0 || *errno_value == ECONNRESET)
610 {
611 *errno_value = ERRNO_SMTPCLOSED;
612 *message = US string_sprintf("Remote host closed connection "
613 "in response to %s%s", pl, smtp_command);
614 }
615 else *message = US string_sprintf("%s [%s]", host->name, host->address);
616
617 return FALSE;
618 }
619
620
621
622 /*************************************************
623 * Write error message to logs *
624 *************************************************/
625
626 /* This writes to the main log and to the message log.
627
628 Arguments:
629 addr the address item containing error information
630 host the current host
631
632 Returns: nothing
633 */
634
635 static void
636 write_logs(address_item *addr, host_item *host)
637 {
638 uschar * message = LOGGING(outgoing_port)
639 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
640 host->port == PORT_NONE ? 25 : host->port)
641 : string_sprintf("H=%s [%s]", host->name, host->address);
642
643 if (addr->message)
644 {
645 message = string_sprintf("%s: %s", message, addr->message);
646 if (addr->basic_errno > 0)
647 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
648 log_write(0, LOG_MAIN, "%s", message);
649 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
650 }
651 else
652 {
653 const uschar * s = exim_errstr(addr->basic_errno);
654 log_write(0, LOG_MAIN, "%s %s", message, s);
655 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
656 }
657 }
658
659 static void
660 msglog_line(host_item * host, uschar * message)
661 {
662 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
663 host->name, host->address, message);
664 }
665
666
667
668 #ifndef DISABLE_EVENT
669 /*************************************************
670 * Post-defer action *
671 *************************************************/
672
673 /* This expands an arbitrary per-transport string.
674 It might, for example, be used to write to the database log.
675
676 Arguments:
677 addr the address item containing error information
678 host the current host
679
680 Returns: nothing
681 */
682
683 static void
684 deferred_event_raise(address_item *addr, host_item *host)
685 {
686 uschar * action = addr->transport->event_action;
687 const uschar * save_domain;
688 uschar * save_local;
689
690 if (!action)
691 return;
692
693 save_domain = deliver_domain;
694 save_local = deliver_localpart;
695
696 /*XXX would ip & port already be set up? */
697 deliver_host_address = string_copy(host->address);
698 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
699 event_defer_errno = addr->basic_errno;
700
701 router_name = addr->router->name;
702 transport_name = addr->transport->name;
703 deliver_domain = addr->domain;
704 deliver_localpart = addr->local_part;
705
706 (void) event_raise(action, US"msg:host:defer",
707 addr->message
708 ? addr->basic_errno > 0
709 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
710 : string_copy(addr->message)
711 : addr->basic_errno > 0
712 ? string_copy(US strerror(addr->basic_errno))
713 : NULL);
714
715 deliver_localpart = save_local;
716 deliver_domain = save_domain;
717 router_name = transport_name = NULL;
718 }
719 #endif
720
721 /*************************************************
722 * Synchronize SMTP responses *
723 *************************************************/
724
725 /* This function is called from smtp_deliver() to receive SMTP responses from
726 the server, and match them up with the commands to which they relate. When
727 PIPELINING is not in use, this function is called after every command, and is
728 therefore somewhat over-engineered, but it is simpler to use a single scheme
729 that works both with and without PIPELINING instead of having two separate sets
730 of code.
731
732 The set of commands that are buffered up with pipelining may start with MAIL
733 and may end with DATA; in between are RCPT commands that correspond to the
734 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
735 etc.) are never buffered.
736
737 Errors after MAIL or DATA abort the whole process leaving the response in the
738 buffer. After MAIL, pending responses are flushed, and the original command is
739 re-instated in big_buffer for error messages. For RCPT commands, the remote is
740 permitted to reject some recipient addresses while accepting others. However
741 certain errors clearly abort the whole process. Set the value in
742 transport_return to PENDING_OK if the address is accepted. If there is a
743 subsequent general error, it will get reset accordingly. If not, it will get
744 converted to OK at the end.
745
746 Arguments:
747 addrlist the complete address list
748 include_affixes TRUE if affixes include in RCPT
749 sync_addr ptr to the ptr of the one to start scanning at (updated)
750 host the host we are connected to
751 count the number of responses to read
752 address_retry_
753 include_sender true if 4xx retry is to include the sender it its key
754 pending_MAIL true if the first response is for MAIL
755 pending_DATA 0 if last command sent was not DATA
756 +1 if previously had a good recipient
757 -1 if not previously had a good recipient
758 inblock incoming SMTP block
759 timeout timeout value
760 buffer buffer for reading response
761 buffsize size of buffer
762
763 Returns: 3 if at least one address had 2xx and one had 5xx
764 2 if at least one address had 5xx but none had 2xx
765 1 if at least one host had a 2xx response, but none had 5xx
766 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
767 -1 timeout while reading RCPT response
768 -2 I/O or other non-response error for RCPT
769 -3 DATA or MAIL failed - errno and buffer set
770 */
771
772 static int
773 sync_responses(address_item *addrlist, BOOL include_affixes,
774 address_item **sync_addr, host_item *host, int count,
775 BOOL address_retry_include_sender, BOOL pending_MAIL,
776 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
777 int buffsize)
778 {
779 address_item *addr = *sync_addr;
780 int yield = 0;
781
782 /* Handle the response for a MAIL command. On error, reinstate the original
783 command in big_buffer for error message use, and flush any further pending
784 responses before returning, except after I/O errors and timeouts. */
785
786 if (pending_MAIL)
787 {
788 count--;
789 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
790 {
791 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
792 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
793 if (errno == 0 && buffer[0] != 0)
794 {
795 uschar flushbuffer[4096];
796 int save_errno = 0;
797 if (buffer[0] == '4')
798 {
799 save_errno = ERRNO_MAIL4XX;
800 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
801 }
802 while (count-- > 0)
803 {
804 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
805 '2', timeout)
806 && (errno != 0 || flushbuffer[0] == 0))
807 break;
808 }
809 errno = save_errno;
810 }
811
812 if (pending_DATA) count--; /* Number of RCPT responses to come */
813 while (count-- > 0) /* Mark any pending addrs with the host used */
814 {
815 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
816 addr->host_used = host;
817 addr = addr->next;
818 }
819 return -3;
820 }
821 }
822
823 if (pending_DATA) count--; /* Number of RCPT responses to come */
824
825 /* Read and handle the required number of RCPT responses, matching each one up
826 with an address by scanning for the next address whose status is PENDING_DEFER.
827 */
828
829 while (count-- > 0)
830 {
831 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
832
833 /* The address was accepted */
834 addr->host_used = host;
835
836 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
837 {
838 yield |= 1;
839 addr->transport_return = PENDING_OK;
840
841 /* If af_dr_retry_exists is set, there was a routing delay on this address;
842 ensure that any address-specific retry record is expunged. We do this both
843 for the basic key and for the version that also includes the sender. */
844
845 if (testflag(addr, af_dr_retry_exists))
846 {
847 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
848 sender_address);
849 retry_add_item(addr, altkey, rf_delete);
850 retry_add_item(addr, addr->address_retry_key, rf_delete);
851 }
852 }
853
854 /* Timeout while reading the response */
855
856 else if (errno == ETIMEDOUT)
857 {
858 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
859 transport_rcpt_address(addr, include_affixes));
860 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
861 retry_add_item(addr, addr->address_retry_key, 0);
862 update_waiting = FALSE;
863 return -1;
864 }
865
866 /* Handle other errors in obtaining an SMTP response by returning -1. This
867 will cause all the addresses to be deferred. Restore the SMTP command in
868 big_buffer for which we are checking the response, so the error message
869 makes sense. */
870
871 else if (errno != 0 || buffer[0] == 0)
872 {
873 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
874 transport_rcpt_address(addr, include_affixes));
875 return -2;
876 }
877
878 /* Handle SMTP permanent and temporary response codes. */
879
880 else
881 {
882 addr->message =
883 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
884 "%s", transport_rcpt_address(addr, include_affixes),
885 string_printing(buffer));
886 setflag(addr, af_pass_message);
887 msglog_line(host, addr->message);
888
889 /* The response was 5xx */
890
891 if (buffer[0] == '5')
892 {
893 addr->transport_return = FAIL;
894 yield |= 2;
895 }
896
897 /* The response was 4xx */
898
899 else
900 {
901 addr->transport_return = DEFER;
902 addr->basic_errno = ERRNO_RCPT4XX;
903 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
904
905 #ifndef DISABLE_EVENT
906 event_defer_errno = addr->more_errno;
907 msg_event_raise(US"msg:rcpt:host:defer", addr);
908 #endif
909
910 /* Log temporary errors if there are more hosts to be tried.
911 If not, log this last one in the == line. */
912
913 if (host->next)
914 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
915
916 #ifndef DISABLE_EVENT
917 else
918 msg_event_raise(US"msg:rcpt:defer", addr);
919 #endif
920
921 /* Do not put this message on the list of those waiting for specific
922 hosts, as otherwise it is likely to be tried too often. */
923
924 update_waiting = FALSE;
925
926 /* Add a retry item for the address so that it doesn't get tried again
927 too soon. If address_retry_include_sender is true, add the sender address
928 to the retry key. */
929
930 if (address_retry_include_sender)
931 {
932 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
933 sender_address);
934 retry_add_item(addr, altkey, 0);
935 }
936 else retry_add_item(addr, addr->address_retry_key, 0);
937 }
938 }
939 } /* Loop for next RCPT response */
940
941 /* Update where to start at for the next block of responses, unless we
942 have already handled all the addresses. */
943
944 if (addr != NULL) *sync_addr = addr->next;
945
946 /* Handle a response to DATA. If we have not had any good recipients, either
947 previously or in this block, the response is ignored. */
948
949 if (pending_DATA != 0 &&
950 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
951 {
952 int code;
953 uschar *msg;
954 BOOL pass_message;
955 if (pending_DATA > 0 || (yield & 1) != 0)
956 {
957 if (errno == 0 && buffer[0] == '4')
958 {
959 errno = ERRNO_DATA4XX;
960 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
961 }
962 return -3;
963 }
964 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
965 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
966 "is in use and there were no good recipients\n", msg);
967 }
968
969 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
970 present) received 3xx. If any RCPTs were handled and yielded anything other
971 than 4xx, yield will be set non-zero. */
972
973 return yield;
974 }
975
976
977
978 /* Do the client side of smtp-level authentication */
979 /*
980 Arguments:
981 buffer EHLO response from server (gets overwritten)
982 addrlist chain of potential addresses to deliver
983 host host to deliver to
984 ob transport options
985 ibp, obp comms channel control blocks
986
987 Returns:
988 OK Success, or failed (but not required): global "smtp_authenticated" set
989 DEFER Failed authentication (and was required)
990 ERROR Internal problem
991
992 FAIL_SEND Failed communications - transmit
993 FAIL - response
994 */
995
996 int
997 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
998 smtp_transport_options_block *ob, BOOL is_esmtp,
999 smtp_inblock *ibp, smtp_outblock *obp)
1000 {
1001 int require_auth;
1002 uschar *fail_reason = US"server did not advertise AUTH support";
1003
1004 smtp_authenticated = FALSE;
1005 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1006 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1007
1008 if (is_esmtp && !regex_AUTH) regex_AUTH =
1009 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1010 FALSE, TRUE);
1011
1012 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1013 {
1014 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1015 expand_nmax = -1; /* reset */
1016
1017 /* Must not do this check until after we have saved the result of the
1018 regex match above. */
1019
1020 if (require_auth == OK ||
1021 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1022 {
1023 auth_instance *au;
1024 fail_reason = US"no common mechanisms were found";
1025
1026 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1027
1028 /* Scan the configured authenticators looking for one which is configured
1029 for use as a client, which is not suppressed by client_condition, and
1030 whose name matches an authentication mechanism supported by the server.
1031 If one is found, attempt to authenticate by calling its client function.
1032 */
1033
1034 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1035 {
1036 uschar *p = names;
1037 if (!au->client ||
1038 (au->client_condition != NULL &&
1039 !expand_check_condition(au->client_condition, au->name,
1040 US"client authenticator")))
1041 {
1042 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1043 au->name,
1044 (au->client)? "client_condition is false" :
1045 "not configured as a client");
1046 continue;
1047 }
1048
1049 /* Loop to scan supported server mechanisms */
1050
1051 while (*p != 0)
1052 {
1053 int rc;
1054 int len = Ustrlen(au->public_name);
1055 while (isspace(*p)) p++;
1056
1057 if (strncmpic(au->public_name, p, len) != 0 ||
1058 (p[len] != 0 && !isspace(p[len])))
1059 {
1060 while (*p != 0 && !isspace(*p)) p++;
1061 continue;
1062 }
1063
1064 /* Found data for a listed mechanism. Call its client entry. Set
1065 a flag in the outblock so that data is overwritten after sending so
1066 that reflections don't show it. */
1067
1068 fail_reason = US"authentication attempt(s) failed";
1069 obp->authenticating = TRUE;
1070 rc = (au->info->clientcode)(au, ibp, obp,
1071 ob->command_timeout, buffer, bufsize);
1072 obp->authenticating = FALSE;
1073 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1074 au->name, rc);
1075
1076 /* A temporary authentication failure must hold up delivery to
1077 this host. After a permanent authentication failure, we carry on
1078 to try other authentication methods. If all fail hard, try to
1079 deliver the message unauthenticated unless require_auth was set. */
1080
1081 switch(rc)
1082 {
1083 case OK:
1084 smtp_authenticated = TRUE; /* stops the outer loop */
1085 client_authenticator = au->name;
1086 if (au->set_client_id != NULL)
1087 client_authenticated_id = expand_string(au->set_client_id);
1088 break;
1089
1090 /* Failure after writing a command */
1091
1092 case FAIL_SEND:
1093 return FAIL_SEND;
1094
1095 /* Failure after reading a response */
1096
1097 case FAIL:
1098 if (errno != 0 || buffer[0] != '5') return FAIL;
1099 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1100 au->name, host->name, host->address, buffer);
1101 break;
1102
1103 /* Failure by some other means. In effect, the authenticator
1104 decided it wasn't prepared to handle this case. Typically this
1105 is the result of "fail" in an expansion string. Do we need to
1106 log anything here? Feb 2006: a message is now put in the buffer
1107 if logging is required. */
1108
1109 case CANCELLED:
1110 if (*buffer != 0)
1111 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1112 "authentication H=%s [%s] %s", au->name, host->name,
1113 host->address, buffer);
1114 break;
1115
1116 /* Internal problem, message in buffer. */
1117
1118 case ERROR:
1119 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1120 DEFER, FALSE);
1121 return ERROR;
1122 }
1123
1124 break; /* If not authenticated, try next authenticator */
1125 } /* Loop for scanning supported server mechanisms */
1126 } /* Loop for further authenticators */
1127 }
1128 }
1129
1130 /* If we haven't authenticated, but are required to, give up. */
1131
1132 if (require_auth == OK && !smtp_authenticated)
1133 {
1134 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1135 string_sprintf("authentication required but %s", fail_reason), DEFER,
1136 FALSE);
1137 return DEFER;
1138 }
1139
1140 return OK;
1141 }
1142
1143
1144 /* Construct AUTH appendix string for MAIL TO */
1145 /*
1146 Arguments
1147 buffer to build string
1148 addrlist chain of potential addresses to deliver
1149 ob transport options
1150
1151 Globals smtp_authenticated
1152 client_authenticated_sender
1153 Return True on error, otherwise buffer has (possibly empty) terminated string
1154 */
1155
1156 BOOL
1157 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1158 smtp_transport_options_block *ob)
1159 {
1160 uschar *local_authenticated_sender = authenticated_sender;
1161
1162 #ifdef notdef
1163 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1164 #endif
1165
1166 if (ob->authenticated_sender != NULL)
1167 {
1168 uschar *new = expand_string(ob->authenticated_sender);
1169 if (new == NULL)
1170 {
1171 if (!expand_string_forcedfail)
1172 {
1173 uschar *message = string_sprintf("failed to expand "
1174 "authenticated_sender: %s", expand_string_message);
1175 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1176 return TRUE;
1177 }
1178 }
1179 else if (new[0] != 0) local_authenticated_sender = new;
1180 }
1181
1182 /* Add the authenticated sender address if present */
1183
1184 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1185 local_authenticated_sender != NULL)
1186 {
1187 string_format(buffer, bufsize, " AUTH=%s",
1188 auth_xtextencode(local_authenticated_sender,
1189 Ustrlen(local_authenticated_sender)));
1190 client_authenticated_sender = string_copy(local_authenticated_sender);
1191 }
1192 else
1193 *buffer= 0;
1194
1195 return FALSE;
1196 }
1197
1198
1199
1200 #ifdef EXPERIMENTAL_DANE
1201 /* Lookup TLSA record for host/port.
1202 Return: OK success with dnssec; DANE mode
1203 DEFER Do not use this host now, may retry later
1204 FAIL_FORCED No TLSA record; DANE not usable
1205 FAIL Do not use this connection
1206 */
1207
1208 int
1209 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1210 {
1211 /* move this out to host.c given the similarity to dns_lookup() ? */
1212 uschar buffer[300];
1213 const uschar * fullname = buffer;
1214
1215 /* TLSA lookup string */
1216 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1217
1218 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1219 {
1220 case DNS_SUCCEED:
1221 if (!dns_is_secure(dnsa))
1222 {
1223 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1224 return DEFER;
1225 }
1226 return OK;
1227
1228 case DNS_AGAIN:
1229 return DEFER; /* just defer this TLS'd conn */
1230
1231 case DNS_NODATA: /* no TLSA RR for this lookup */
1232 case DNS_NOMATCH: /* no records at all for this lookup */
1233 return dane_required ? FAIL : FAIL_FORCED;
1234
1235 default:
1236 case DNS_FAIL:
1237 return dane_required ? FAIL : DEFER;
1238 }
1239 }
1240 #endif
1241
1242
1243
1244 typedef struct smtp_compare_s
1245 {
1246 uschar *current_sender_address;
1247 struct transport_instance *tblock;
1248 } smtp_compare_t;
1249
1250 /*
1251 Create a unique string that identifies this message, it is based on
1252 sender_address, helo_data and tls_certificate if enabled. */
1253
1254 static uschar *
1255 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1256 {
1257 address_item * addr1;
1258 uschar * if1 = US"";
1259 uschar * helo1 = US"";
1260 #ifdef SUPPORT_TLS
1261 uschar * tlsc1 = US"";
1262 #endif
1263 uschar * save_sender_address = sender_address;
1264 uschar * local_identity = NULL;
1265 smtp_transport_options_block * ob =
1266 (smtp_transport_options_block *)tblock->options_block;
1267
1268 sender_address = sender;
1269
1270 addr1 = deliver_make_addr (sender, TRUE);
1271 deliver_set_expansions(addr1);
1272
1273 if (ob->interface)
1274 if1 = expand_string(ob->interface);
1275
1276 if (ob->helo_data)
1277 helo1 = expand_string(ob->helo_data);
1278
1279 #ifdef SUPPORT_TLS
1280 if (ob->tls_certificate)
1281 tlsc1 = expand_string(ob->tls_certificate);
1282 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1283 #else
1284 local_identity = string_sprintf ("%s^%s", if1, helo1);
1285 #endif
1286
1287 deliver_set_expansions(NULL);
1288 sender_address = save_sender_address;
1289
1290 return local_identity;
1291 }
1292
1293
1294
1295 /* This routine is a callback that is called from transport_check_waiting.
1296 This function will evaluate the incoming message versus the previous
1297 message. If the incoming message is using a different local identity then
1298 we will veto this new message. */
1299
1300 static BOOL
1301 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1302 {
1303 uschar * message_local_identity,
1304 * current_local_identity,
1305 * new_sender_address;
1306
1307 current_local_identity =
1308 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1309
1310 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1311 return 0;
1312
1313 message_local_identity =
1314 smtp_local_identity(new_sender_address, s_compare->tblock);
1315
1316 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1317 }
1318
1319
1320
1321 uschar
1322 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1323 {
1324 #ifdef SUPPORT_TLS
1325 if ( checks & PEER_OFFERED_TLS
1326 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1327 checks &= ~PEER_OFFERED_TLS;
1328 #endif
1329
1330 if ( checks & PEER_OFFERED_IGNQ
1331 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1332 PCRE_EOPT, NULL, 0) < 0)
1333 checks &= ~PEER_OFFERED_IGNQ;
1334
1335 if ( checks & PEER_OFFERED_CHUNKING
1336 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1337 checks &= ~PEER_OFFERED_CHUNKING;
1338
1339 #ifndef DISABLE_PRDR
1340 if ( checks & PEER_OFFERED_PRDR
1341 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1342 checks &= ~PEER_OFFERED_PRDR;
1343 #endif
1344
1345 #ifdef SUPPORT_I18N
1346 if ( checks & PEER_OFFERED_UTF8
1347 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1348 checks &= ~PEER_OFFERED_UTF8;
1349 #endif
1350
1351 if ( checks & PEER_OFFERED_DSN
1352 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1353 checks &= ~PEER_OFFERED_DSN;
1354
1355 if ( checks & PEER_OFFERED_PIPE
1356 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1357 PCRE_EOPT, NULL, 0) < 0)
1358 checks &= ~PEER_OFFERED_PIPE;
1359
1360 if ( checks & PEER_OFFERED_SIZE
1361 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1362 checks &= ~PEER_OFFERED_SIZE;
1363
1364 return checks;
1365 }
1366
1367
1368
1369 /* Callback for emitting a BDAT data chunk header.
1370
1371 If given a nonzero size, first flush any buffered SMTP commands
1372 then emit the command.
1373
1374 Reap previous SMTP command responses if requested.
1375 Reap one SMTP command response if requested.
1376
1377 Returns: OK or ERROR
1378 */
1379
1380 static int
1381 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1382 unsigned chunk_size, unsigned flags)
1383 {
1384 smtp_transport_options_block * ob =
1385 (smtp_transport_options_block *)(tctx->tblock->options_block);
1386 int cmd_count = 0;
1387 int prev_cmd_count;
1388 uschar * buffer = tctx->buffer;
1389
1390
1391 /* Write SMTP chunk header command */
1392
1393 if (chunk_size > 0)
1394 {
1395 if((cmd_count = smtp_write_command(tctx->outblock, FALSE, "BDAT %u%s\r\n",
1396 chunk_size,
1397 flags & tc_chunk_last ? " LAST" : "")
1398 ) < 0) return ERROR;
1399 if (flags & tc_chunk_last)
1400 data_command = string_copy(big_buffer); /* Save for later error message */
1401 }
1402
1403 prev_cmd_count = cmd_count += tctx->cmd_count;
1404
1405 /* Reap responses for any previous, but not one we just emitted */
1406
1407 if (chunk_size > 0)
1408 prev_cmd_count--;
1409 if (tctx->pending_BDAT)
1410 prev_cmd_count--;
1411
1412 if (flags & tc_reap_prev && prev_cmd_count > 0)
1413 {
1414 DEBUG(D_transport) debug_printf("look for %d responses"
1415 " for previous pipelined cmds\n", prev_cmd_count);
1416
1417 switch(sync_responses(tctx->first_addr, tctx->tblock->rcpt_include_affixes,
1418 tctx->sync_addr, tctx->host, prev_cmd_count,
1419 ob->address_retry_include_sender,
1420 tctx->pending_MAIL, 0,
1421 tctx->inblock,
1422 ob->command_timeout,
1423 buffer, DELIVER_BUFFER_SIZE))
1424 {
1425 case 1: /* 2xx (only) => OK */
1426 case 3: tctx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1427 case 2: *tctx->completed_address = TRUE; /* 5xx (only) => progress made */
1428 case 0: break; /* No 2xx or 5xx, but no probs */
1429
1430 case -1: /* Timeout on RCPT */
1431 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1432 }
1433 cmd_count = 1;
1434 if (!tctx->pending_BDAT)
1435 pipelining_active = FALSE;
1436 }
1437
1438 /* Reap response for an outstanding BDAT */
1439
1440 if (tctx->pending_BDAT)
1441 {
1442 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1443
1444 if (!smtp_read_response(tctx->inblock, buffer, DELIVER_BUFFER_SIZE, '2',
1445 ob->command_timeout))
1446 {
1447 if (errno == 0 && buffer[0] == '4')
1448 {
1449 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1450 tctx->first_addr->more_errno |=
1451 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1452 }
1453 return ERROR;
1454 }
1455 cmd_count--;
1456 tctx->pending_BDAT = FALSE;
1457 pipelining_active = FALSE;
1458 }
1459 else if (chunk_size > 0)
1460 tctx->pending_BDAT = TRUE;
1461
1462
1463 tctx->cmd_count = cmd_count;
1464 return OK;
1465 }
1466
1467
1468
1469 /*************************************************
1470 * Deliver address list to given host *
1471 *************************************************/
1472
1473 /* If continue_hostname is not null, we get here only when continuing to
1474 deliver down an existing channel. The channel was passed as the standard
1475 input. TLS is never active on a passed channel; the previous process always
1476 closes it down before passing the connection on.
1477
1478 Otherwise, we have to make a connection to the remote host, and do the
1479 initial protocol exchange.
1480
1481 When running as an MUA wrapper, if the sender or any recipient is rejected,
1482 temporarily or permanently, we force failure for all recipients.
1483
1484 Arguments:
1485 addrlist chain of potential addresses to deliver; only those whose
1486 transport_return field is set to PENDING_DEFER are currently
1487 being processed; others should be skipped - they have either
1488 been delivered to an earlier host or IP address, or been
1489 failed by one of them.
1490 host host to deliver to
1491 host_af AF_INET or AF_INET6
1492 port default TCP/IP port to use, in host byte order
1493 interface interface to bind to, or NULL
1494 tblock transport instance block
1495 message_defer set TRUE if yield is OK, but all addresses were deferred
1496 because of a non-recipient, non-host failure, that is, a
1497 4xx response to MAIL FROM, DATA, or ".". This is a defer
1498 that is specific to the message.
1499 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1500 a second attempt after TLS initialization fails
1501
1502 Returns: OK - the connection was made and the delivery attempted;
1503 the result for each address is in its data block.
1504 DEFER - the connection could not be made, or something failed
1505 while setting up the SMTP session, or there was a
1506 non-message-specific error, such as a timeout.
1507 ERROR - a filter command is specified for this transport,
1508 and there was a problem setting it up; OR helo_data
1509 or add_headers or authenticated_sender is specified
1510 for this transport, and the string failed to expand
1511 */
1512
1513 static int
1514 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1515 uschar *interface, transport_instance *tblock,
1516 BOOL *message_defer, BOOL suppress_tls)
1517 {
1518 address_item *addr;
1519 address_item *sync_addr;
1520 address_item *first_addr = addrlist;
1521 int yield = OK;
1522 int address_count;
1523 int save_errno;
1524 int rc;
1525 time_t start_delivery_time = time(NULL);
1526 smtp_transport_options_block *ob =
1527 (smtp_transport_options_block *)(tblock->options_block);
1528 struct lflags {
1529 BOOL lmtp:1;
1530 BOOL smtps:1;
1531 BOOL ok:1;
1532 BOOL send_rset:1;
1533 BOOL send_quit:1;
1534 BOOL setting_up:1;
1535 BOOL esmtp:1;
1536 BOOL esmtp_sent:1;
1537 BOOL pending_MAIL:1;
1538 #ifndef DISABLE_PRDR
1539 BOOL prdr_active:1;
1540 #endif
1541 #ifdef SUPPORT_I18N
1542 BOOL utf8_needed:1;
1543 #endif
1544 BOOL dsn_all_lasthop:1;
1545 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1546 BOOL dane:1;
1547 BOOL dane_required:1;
1548 #endif
1549 } lflags;
1550
1551 BOOL pass_message = FALSE;
1552 BOOL completed_address = FALSE;
1553 uschar peer_offered = 0;
1554 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1555 dns_answer tlsa_dnsa;
1556 #endif
1557 smtp_inblock inblock;
1558 smtp_outblock outblock;
1559 int max_rcpt = tblock->max_addresses;
1560 uschar *igquotstr = US"";
1561
1562 #ifdef EXPERIMENTAL_DSN_INFO
1563 uschar *smtp_greeting = NULL;
1564 uschar *helo_response = NULL;
1565 #endif
1566 uschar *helo_data = NULL;
1567
1568 uschar *message = NULL;
1569 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1570 uschar *p;
1571 uschar buffer[DELIVER_BUFFER_SIZE];
1572 uschar inbuffer[4096];
1573 uschar outbuffer[4096];
1574
1575 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1576
1577 lflags.lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1578 lflags.smtps = strcmpic(ob->protocol, US"smtps") == 0;
1579 lflags.ok = FALSE;
1580 lflags.send_rset = TRUE;
1581 lflags.send_quit = TRUE;
1582 lflags.setting_up = TRUE;
1583 lflags.esmtp = TRUE;
1584 lflags.esmtp_sent = FALSE;
1585 #ifdef SUPPORT_I18N
1586 lflags.utf8_needed = FALSE;
1587 #endif
1588 lflags.dsn_all_lasthop = TRUE;
1589 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1590 lflags.dane = FALSE;
1591 lflags.dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1592 #endif
1593
1594 *message_defer = FALSE;
1595 smtp_command = US"initial connection";
1596 buffer[0] = '\0';
1597 if (max_rcpt == 0) max_rcpt = 999999;
1598
1599 /* Set up the buffer for reading SMTP response packets. */
1600
1601 inblock.buffer = inbuffer;
1602 inblock.buffersize = sizeof(inbuffer);
1603 inblock.ptr = inbuffer;
1604 inblock.ptrend = inbuffer;
1605
1606 /* Set up the buffer for holding SMTP commands while pipelining */
1607
1608 outblock.buffer = outbuffer;
1609 outblock.buffersize = sizeof(outbuffer);
1610 outblock.ptr = outbuffer;
1611 outblock.cmd_count = 0;
1612 outblock.authenticating = FALSE;
1613
1614 /* Reset the parameters of a TLS session. */
1615
1616 tls_out.bits = 0;
1617 tls_out.cipher = NULL; /* the one we may use for this transport */
1618 tls_out.ourcert = NULL;
1619 tls_out.peercert = NULL;
1620 tls_out.peerdn = NULL;
1621 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1622 tls_out.sni = NULL;
1623 #endif
1624 tls_out.ocsp = OCSP_NOT_REQ;
1625
1626 /* Flip the legacy TLS-related variables over to the outbound set in case
1627 they're used in the context of the transport. Don't bother resetting
1628 afterward as we're in a subprocess. */
1629
1630 tls_modify_variables(&tls_out);
1631
1632 #ifndef SUPPORT_TLS
1633 if (lflags.smtps)
1634 {
1635 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1636 DEFER, FALSE);
1637 return ERROR;
1638 }
1639 #endif
1640
1641 /* Make a connection to the host if this isn't a continued delivery, and handle
1642 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1643 specially so they can be identified for retries. */
1644
1645 if (continue_hostname == NULL)
1646 {
1647 /* This puts port into host->port */
1648 inblock.sock = outblock.sock =
1649 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1650
1651 if (inblock.sock < 0)
1652 {
1653 set_errno_nohost(addrlist, errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1654 NULL, DEFER, FALSE);
1655 return DEFER;
1656 }
1657
1658 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1659 {
1660 tls_out.dane_verified = FALSE;
1661 tls_out.tlsa_usage = 0;
1662
1663 if (host->dnssec == DS_YES)
1664 {
1665 if( lflags.dane_required
1666 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1667 )
1668 switch (rc = tlsa_lookup(host, &tlsa_dnsa, lflags.dane_required))
1669 {
1670 case OK: lflags.dane = TRUE; break;
1671 case FAIL_FORCED: break;
1672 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1673 string_sprintf("DANE error: tlsa lookup %s",
1674 rc == DEFER ? "DEFER" : "FAIL"),
1675 rc, FALSE);
1676 return rc;
1677 }
1678 }
1679 else if (lflags.dane_required)
1680 {
1681 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1682 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1683 FAIL, FALSE);
1684 return FAIL;
1685 }
1686
1687 if (lflags.dane)
1688 ob->tls_tempfail_tryclear = FALSE;
1689 }
1690 #endif /*DANE*/
1691
1692 /* Expand the greeting message while waiting for the initial response. (Makes
1693 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1694 delayed till here so that $sending_interface and $sending_port are set. */
1695
1696 helo_data = expand_string(ob->helo_data);
1697 #ifdef SUPPORT_I18N
1698 if (helo_data)
1699 {
1700 uschar * errstr = NULL;
1701 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1702 {
1703 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1704 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1705 yield = DEFER;
1706 goto SEND_QUIT;
1707 }
1708 }
1709 #endif
1710
1711 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1712 is nevertheless a reasonably clean way of programming this kind of logic,
1713 where you want to escape on any error. */
1714
1715 if (!lflags.smtps)
1716 {
1717 BOOL good_response;
1718
1719 #ifdef TCP_QUICKACK
1720 (void) setsockopt(inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1721 #endif
1722 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1723 '2', ob->command_timeout);
1724 #ifdef EXPERIMENTAL_DSN_INFO
1725 smtp_greeting = string_copy(buffer);
1726 #endif
1727 if (!good_response) goto RESPONSE_FAILED;
1728
1729 #ifndef DISABLE_EVENT
1730 {
1731 uschar * s;
1732 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1733 : host->dnssec==DS_NO ? US"no" : NULL;
1734 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1735 if (s)
1736 {
1737 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1738 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1739 DEFER, FALSE);
1740 yield = DEFER;
1741 goto SEND_QUIT;
1742 }
1743 }
1744 #endif
1745
1746 /* Now check if the helo_data expansion went well, and sign off cleanly if
1747 it didn't. */
1748
1749 if (!helo_data)
1750 {
1751 uschar *message = string_sprintf("failed to expand helo_data: %s",
1752 expand_string_message);
1753 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1754 yield = DEFER;
1755 goto SEND_QUIT;
1756 }
1757 }
1758
1759 /** Debugging without sending a message
1760 addrlist->transport_return = DEFER;
1761 goto SEND_QUIT;
1762 **/
1763
1764 /* Errors that occur after this point follow an SMTP command, which is
1765 left in big_buffer by smtp_write_command() for use in error messages. */
1766
1767 smtp_command = big_buffer;
1768
1769 /* Tell the remote who we are...
1770
1771 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1772 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1773 greeting is of this form. The assumption was that the far end supports it
1774 properly... but experience shows that there are some that give 5xx responses,
1775 even though the banner includes "ESMTP" (there's a bloody-minded one that
1776 says "ESMTP not spoken here"). Cope with that case.
1777
1778 September 2000: Time has passed, and it seems reasonable now to always send
1779 EHLO at the start. It is also convenient to make the change while installing
1780 the TLS stuff.
1781
1782 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1783 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1784 would be no way to send out the mails, so there is now a host list
1785 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1786 PIPELINING problem as well. Maybe it can also be useful to cure other
1787 problems with broken servers.
1788
1789 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1790 Then somebody tried it with a Microsoft mailer... It seems that all other
1791 mailers use upper case for some reason (the RFC is quite clear about case
1792 independence) so, for peace of mind, I gave in. */
1793
1794 lflags.esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1795
1796 /* Alas; be careful, since this goto is not an error-out, so conceivably
1797 we might set data between here and the target which we assume to exist
1798 and be usable. I can see this coming back to bite us. */
1799 #ifdef SUPPORT_TLS
1800 if (lflags.smtps)
1801 {
1802 smtp_peer_options |= PEER_OFFERED_TLS;
1803 suppress_tls = FALSE;
1804 ob->tls_tempfail_tryclear = FALSE;
1805 smtp_command = US"SSL-on-connect";
1806 goto TLS_NEGOTIATE;
1807 }
1808 #endif
1809
1810 if (lflags.esmtp)
1811 {
1812 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1813 lflags.lmtp ? "LHLO" : "EHLO", helo_data) < 0)
1814 goto SEND_FAILED;
1815 lflags.esmtp_sent = TRUE;
1816 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1817 ob->command_timeout))
1818 {
1819 if (errno != 0 || buffer[0] == 0 || lflags.lmtp)
1820 {
1821 #ifdef EXPERIMENTAL_DSN_INFO
1822 helo_response = string_copy(buffer);
1823 #endif
1824 goto RESPONSE_FAILED;
1825 }
1826 lflags.esmtp = FALSE;
1827 }
1828 #ifdef EXPERIMENTAL_DSN_INFO
1829 helo_response = string_copy(buffer);
1830 #endif
1831 }
1832 else
1833 DEBUG(D_transport)
1834 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1835
1836 if (!lflags.esmtp)
1837 {
1838 BOOL good_response;
1839 int n = sizeof(buffer);
1840 uschar * rsp = buffer;
1841
1842 if (lflags.esmtp_sent && (n = Ustrlen(buffer)) < sizeof(buffer)/2)
1843 { rsp = buffer + n + 1; n = sizeof(buffer) - n; }
1844
1845 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1846 goto SEND_FAILED;
1847 good_response = smtp_read_response(&inblock, rsp, n,
1848 '2', ob->command_timeout);
1849 #ifdef EXPERIMENTAL_DSN_INFO
1850 helo_response = string_copy(rsp);
1851 #endif
1852 if (!good_response)
1853 {
1854 /* Handle special logging for a closed connection after HELO
1855 when had previously sent EHLO */
1856
1857 if (rsp != buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1858 {
1859 message = NULL;
1860 lflags.send_quit = FALSE;
1861 save_errno = ERRNO_SMTPCLOSED;
1862 message = string_sprintf("Remote host closed connection "
1863 "in response to %s (EHLO response was: %s)",
1864 smtp_command, buffer);
1865 goto FAILED;
1866 }
1867 Ustrncpy(buffer, rsp, sizeof(buffer)/2);
1868 goto RESPONSE_FAILED;
1869 }
1870 }
1871
1872 peer_offered = smtp_peer_options = 0;
1873
1874 if (lflags.esmtp || lflags.lmtp)
1875 {
1876 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1877 PEER_OFFERED_TLS /* others checked later */
1878 );
1879
1880 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1881
1882 #ifdef SUPPORT_TLS
1883 smtp_peer_options |= peer_offered & PEER_OFFERED_TLS;
1884 #endif
1885 }
1886 }
1887
1888 /* For continuing deliveries down the same channel, the socket is the standard
1889 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1890 below). Set up the pointer to where subsequent commands will be left, for
1891 error messages. Note that smtp_peer_options will have been
1892 set from the command line if they were set in the process that passed the
1893 connection on. */
1894
1895 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1896 as the contine goes via transport_pass_socket() and doublefork and exec.
1897 It does not wait. Unclear how we keep separate host's responses
1898 separate - we could match up by host ip+port as a bodge. */
1899
1900 else
1901 {
1902 inblock.sock = outblock.sock = fileno(stdin);
1903 smtp_command = big_buffer;
1904 host->port = port; /* Record the port that was used */
1905 }
1906
1907 /* If TLS is available on this connection, whether continued or not, attempt to
1908 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1909 send another EHLO - the server may give a different answer in secure mode. We
1910 use a separate buffer for reading the response to STARTTLS so that if it is
1911 negative, the original EHLO data is available for subsequent analysis, should
1912 the client not be required to use TLS. If the response is bad, copy the buffer
1913 for error analysis. */
1914
1915 #ifdef SUPPORT_TLS
1916 if ( smtp_peer_options & PEER_OFFERED_TLS
1917 && !suppress_tls
1918 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1919 {
1920 uschar buffer2[4096];
1921 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1922 goto SEND_FAILED;
1923
1924 /* If there is an I/O error, transmission of this message is deferred. If
1925 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1926 false, we also defer. However, if there is a temporary rejection of STARTTLS
1927 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1928 STARTTLS, we carry on. This means we will try to send the message in clear,
1929 unless the host is in hosts_require_tls (tested below). */
1930
1931 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1932 ob->command_timeout))
1933 {
1934 if ( errno != 0
1935 || buffer2[0] == 0
1936 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1937 )
1938 {
1939 Ustrncpy(buffer, buffer2, sizeof(buffer));
1940 goto RESPONSE_FAILED;
1941 }
1942 }
1943
1944 /* STARTTLS accepted: try to negotiate a TLS session. */
1945
1946 else
1947 TLS_NEGOTIATE:
1948 {
1949 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1950 # ifdef EXPERIMENTAL_DANE
1951 , lflags.dane ? &tlsa_dnsa : NULL
1952 # endif
1953 );
1954
1955 /* TLS negotiation failed; give an error. From outside, this function may
1956 be called again to try in clear on a new connection, if the options permit
1957 it for this host. */
1958
1959 if (rc != OK)
1960 {
1961 # ifdef EXPERIMENTAL_DANE
1962 if (lflags.dane) log_write(0, LOG_MAIN,
1963 "DANE attempt failed; no TLS connection to %s [%s]",
1964 host->name, host->address);
1965 # endif
1966
1967 save_errno = ERRNO_TLSFAILURE;
1968 message = US"failure while setting up TLS session";
1969 lflags.send_quit = FALSE;
1970 goto TLS_FAILED;
1971 }
1972
1973 /* TLS session is set up */
1974
1975 smtp_peer_options_wrap = smtp_peer_options;
1976 for (addr = addrlist; addr; addr = addr->next)
1977 if (addr->transport_return == PENDING_DEFER)
1978 {
1979 addr->cipher = tls_out.cipher;
1980 addr->ourcert = tls_out.ourcert;
1981 addr->peercert = tls_out.peercert;
1982 addr->peerdn = tls_out.peerdn;
1983 addr->ocsp = tls_out.ocsp;
1984 }
1985 }
1986 }
1987
1988 /* if smtps, we'll have smtp_command set to something else; always safe to
1989 reset it here. */
1990 smtp_command = big_buffer;
1991
1992 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1993 helo_data is null, we are dealing with a connection that was passed from
1994 another process, and so we won't have expanded helo_data above. We have to
1995 expand it here. $sending_ip_address and $sending_port are set up right at the
1996 start of the Exim process (in exim.c). */
1997
1998 if (tls_out.active >= 0)
1999 {
2000 char *greeting_cmd;
2001 BOOL good_response;
2002
2003 if (helo_data == NULL)
2004 {
2005 helo_data = expand_string(ob->helo_data);
2006 if (helo_data == NULL)
2007 {
2008 uschar *message = string_sprintf("failed to expand helo_data: %s",
2009 expand_string_message);
2010 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2011 yield = DEFER;
2012 goto SEND_QUIT;
2013 }
2014 }
2015
2016 /* For SMTPS we need to wait for the initial OK response. */
2017 if (lflags.smtps)
2018 {
2019 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2020 '2', ob->command_timeout);
2021 #ifdef EXPERIMENTAL_DSN_INFO
2022 smtp_greeting = string_copy(buffer);
2023 #endif
2024 if (!good_response) goto RESPONSE_FAILED;
2025 }
2026
2027 if (lflags.esmtp)
2028 greeting_cmd = "EHLO";
2029 else
2030 {
2031 greeting_cmd = "HELO";
2032 DEBUG(D_transport)
2033 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2034 }
2035
2036 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
2037 lflags.lmtp ? "LHLO" : greeting_cmd, helo_data) < 0)
2038 goto SEND_FAILED;
2039 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2040 '2', ob->command_timeout);
2041 #ifdef EXPERIMENTAL_DSN_INFO
2042 helo_response = string_copy(buffer);
2043 #endif
2044 if (!good_response) goto RESPONSE_FAILED;
2045 smtp_peer_options = 0;
2046 }
2047
2048 /* If the host is required to use a secure channel, ensure that we
2049 have one. */
2050
2051 else if ( lflags.smtps
2052 # ifdef EXPERIMENTAL_DANE
2053 || lflags.dane
2054 # endif
2055 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
2056 )
2057 {
2058 save_errno = ERRNO_TLSREQUIRED;
2059 message = string_sprintf("a TLS session is required, but %s",
2060 smtp_peer_options & PEER_OFFERED_TLS
2061 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2062 goto TLS_FAILED;
2063 }
2064 #endif /*SUPPORT_TLS*/
2065
2066 /* If TLS is active, we have just started it up and re-done the EHLO command,
2067 so its response needs to be analyzed. If TLS is not active and this is a
2068 continued session down a previously-used socket, we haven't just done EHLO, so
2069 we skip this. */
2070
2071 if (continue_hostname == NULL
2072 #ifdef SUPPORT_TLS
2073 || tls_out.active >= 0
2074 #endif
2075 )
2076 {
2077 if (lflags.esmtp || lflags.lmtp)
2078 {
2079 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
2080 0 /* no TLS */
2081 | (lflags.lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2082 | PEER_OFFERED_CHUNKING
2083 | PEER_OFFERED_PRDR
2084 #ifdef SUPPORT_I18N
2085 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2086 /*XXX if we hand peercaps on to continued-conn processes,
2087 must not depend on this addr */
2088 #endif
2089 | PEER_OFFERED_DSN
2090 | PEER_OFFERED_PIPE
2091 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2092 );
2093
2094 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2095 lmtp_ignore_quota option was set. */
2096
2097 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2098
2099 /* If the response to EHLO specified support for the SIZE parameter, note
2100 this, provided size_addition is non-negative. */
2101
2102 smtp_peer_options |= peer_offered & PEER_OFFERED_SIZE;
2103
2104 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2105 the current host, esmtp will be false, so PIPELINING can never be used. If
2106 the current host matches hosts_avoid_pipelining, don't do it. */
2107
2108 if ( peer_offered & PEER_OFFERED_PIPE
2109 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK)
2110 smtp_peer_options |= PEER_OFFERED_PIPE;
2111
2112 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2113 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2114
2115 if ( peer_offered & PEER_OFFERED_CHUNKING
2116 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
2117 peer_offered &= ~PEER_OFFERED_CHUNKING;
2118
2119 if (peer_offered & PEER_OFFERED_CHUNKING)
2120 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2121
2122 #ifndef DISABLE_PRDR
2123 if ( peer_offered & PEER_OFFERED_PRDR
2124 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
2125 peer_offered &= ~PEER_OFFERED_PRDR;
2126
2127 if (peer_offered & PEER_OFFERED_PRDR)
2128 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2129 #endif
2130
2131 /* Note if the server supports DSN */
2132 smtp_peer_options |= peer_offered & PEER_OFFERED_DSN;
2133 DEBUG(D_transport) debug_printf("%susing DSN\n",
2134 peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2135
2136 /* Note if the response to EHLO specifies support for the AUTH extension.
2137 If it has, check that this host is one we want to authenticate to, and do
2138 the business. The host name and address must be available when the
2139 authenticator's client driver is running. */
2140
2141 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
2142 ob, lflags.esmtp, &inblock, &outblock))
2143 {
2144 default: goto SEND_QUIT;
2145 case OK: break;
2146 case FAIL_SEND: goto SEND_FAILED;
2147 case FAIL: goto RESPONSE_FAILED;
2148 }
2149 }
2150 }
2151 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2152
2153 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2154 message-specific. */
2155
2156 lflags.setting_up = FALSE;
2157
2158 #ifdef SUPPORT_I18N
2159 if (addrlist->prop.utf8_msg)
2160 {
2161 lflags.utf8_needed = !addrlist->prop.utf8_downcvt
2162 && !addrlist->prop.utf8_downcvt_maybe;
2163 DEBUG(D_transport) if (!lflags.utf8_needed)
2164 debug_printf("utf8: %s downconvert\n",
2165 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2166 }
2167
2168 /* If this is an international message we need the host to speak SMTPUTF8 */
2169 if (lflags.utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2170 {
2171 errno = ERRNO_UTF8_FWD;
2172 goto RESPONSE_FAILED;
2173 }
2174 #endif
2175
2176 /* If there is a filter command specified for this transport, we can now
2177 set it up. This cannot be done until the identify of the host is known. */
2178
2179 if (tblock->filter_command != NULL)
2180 {
2181 BOOL rc;
2182 uschar fbuf[64];
2183 sprintf(CS fbuf, "%.50s transport", tblock->name);
2184 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2185 TRUE, DEFER, addrlist, fbuf, NULL);
2186 transport_filter_timeout = tblock->filter_timeout;
2187
2188 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2189 yield ERROR. */
2190
2191 if (!rc)
2192 {
2193 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2194 FALSE);
2195 yield = ERROR;
2196 goto SEND_QUIT;
2197 }
2198
2199 if ( transport_filter_argv
2200 && *transport_filter_argv
2201 && **transport_filter_argv
2202 && peer_offered & PEER_OFFERED_CHUNKING
2203 )
2204 {
2205 peer_offered &= ~PEER_OFFERED_CHUNKING;
2206 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2207 }
2208 }
2209
2210
2211 /* For messages that have more than the maximum number of envelope recipients,
2212 we want to send several transactions down the same SMTP connection. (See
2213 comments in deliver.c as to how this reconciles, heuristically, with
2214 remote_max_parallel.) This optimization was added to Exim after the following
2215 code was already working. The simplest way to put it in without disturbing the
2216 code was to use a goto to jump back to this point when there is another
2217 transaction to handle. */
2218
2219 SEND_MESSAGE:
2220 sync_addr = first_addr;
2221 address_count = 0;
2222 lflags.ok = FALSE;
2223 lflags.send_rset = TRUE;
2224 completed_address = FALSE;
2225
2226
2227 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2228 qualification, send it, adding something to the message size to allow for
2229 imprecision and things that get added en route. Exim keeps the number of lines
2230 in a message, so we can give an accurate value for the original message, but we
2231 need some additional to handle added headers. (Double "." characters don't get
2232 included in the count.) */
2233
2234 p = buffer;
2235 *p = 0;
2236
2237 if (peer_offered & PEER_OFFERED_SIZE)
2238 {
2239 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2240 while (*p) p++;
2241 }
2242
2243 #ifndef DISABLE_PRDR
2244 lflags.prdr_active = FALSE;
2245 if (peer_offered & PEER_OFFERED_PRDR)
2246 for (addr = first_addr; addr; addr = addr->next)
2247 if (addr->transport_return == PENDING_DEFER)
2248 {
2249 for (addr = addr->next; addr; addr = addr->next)
2250 if (addr->transport_return == PENDING_DEFER)
2251 { /* at least two recipients to send */
2252 lflags.prdr_active = TRUE;
2253 sprintf(CS p, " PRDR"); p += 5;
2254 break;
2255 }
2256 break;
2257 }
2258 #endif
2259
2260 #ifdef SUPPORT_I18N
2261 if ( addrlist->prop.utf8_msg
2262 && !addrlist->prop.utf8_downcvt
2263 && peer_offered & PEER_OFFERED_UTF8
2264 )
2265 sprintf(CS p, " SMTPUTF8"), p += 9;
2266 #endif
2267
2268 /* check if all addresses have lasthop flag */
2269 /* do not send RET and ENVID if true */
2270 for (lflags.dsn_all_lasthop = TRUE, addr = first_addr;
2271 address_count < max_rcpt && addr != NULL;
2272 addr = addr->next)
2273 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2274 {
2275 lflags.dsn_all_lasthop = FALSE;
2276 break;
2277 }
2278
2279 /* Add any DSN flags to the mail command */
2280
2281 if (peer_offered & PEER_OFFERED_DSN && !lflags.dsn_all_lasthop)
2282 {
2283 if (dsn_ret == dsn_ret_hdrs)
2284 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2285 else if (dsn_ret == dsn_ret_full)
2286 { Ustrcpy(p, " RET=FULL"); p += 9; }
2287
2288 if (dsn_envid)
2289 {
2290 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2291 while (*p) p++;
2292 }
2293 }
2294
2295 /* If an authenticated_sender override has been specified for this transport
2296 instance, expand it. If the expansion is forced to fail, and there was already
2297 an authenticated_sender for this message, the original value will be used.
2298 Other expansion failures are serious. An empty result is ignored, but there is
2299 otherwise no check - this feature is expected to be used with LMTP and other
2300 cases where non-standard addresses (e.g. without domains) might be required. */
2301
2302 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2303 {
2304 yield = ERROR;
2305 goto SEND_QUIT;
2306 }
2307
2308 /* From here until we send the DATA command, we can make use of PIPELINING
2309 if the server host supports it. The code has to be able to check the responses
2310 at any point, for when the buffer fills up, so we write it totally generally.
2311 When PIPELINING is off, each command written reports that it has flushed the
2312 buffer. */
2313
2314 lflags.pending_MAIL = TRUE; /* The block starts with MAIL */
2315
2316 {
2317 uschar * s = return_path;
2318 #ifdef SUPPORT_I18N
2319 uschar * errstr = NULL;
2320
2321 /* If we must downconvert, do the from-address here. Remember we had to
2322 for the to-addresses (done below), and also (ugly) for re-doing when building
2323 the delivery log line. */
2324
2325 if ( addrlist->prop.utf8_msg
2326 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2327 )
2328 {
2329 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2330 {
2331 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2332 yield = ERROR;
2333 goto SEND_QUIT;
2334 }
2335 setflag(addrlist, af_utf8_downcvt);
2336 }
2337 #endif
2338
2339 rc = smtp_write_command(&outblock, pipelining_active,
2340 "MAIL FROM:<%s>%s\r\n", s, buffer);
2341 }
2342
2343 mail_command = string_copy(big_buffer); /* Save for later error message */
2344
2345 switch(rc)
2346 {
2347 case -1: /* Transmission error */
2348 goto SEND_FAILED;
2349
2350 case +1: /* Block was sent */
2351 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2352 ob->command_timeout))
2353 {
2354 if (errno == 0 && buffer[0] == '4')
2355 {
2356 errno = ERRNO_MAIL4XX;
2357 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2358 }
2359 goto RESPONSE_FAILED;
2360 }
2361 lflags.pending_MAIL = FALSE;
2362 break;
2363 }
2364
2365 /* Pass over all the relevant recipient addresses for this host, which are the
2366 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2367 several before we have to read the responses for those seen so far. This
2368 checking is done by a subroutine because it also needs to be done at the end.
2369 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2370 the next one if not all are sent.
2371
2372 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2373 last address because we want to abort if any recipients have any kind of
2374 problem, temporary or permanent. We know that all recipient addresses will have
2375 the PENDING_DEFER status, because only one attempt is ever made, and we know
2376 that max_rcpt will be large, so all addresses will be done at once. */
2377
2378 for (addr = first_addr;
2379 addr && address_count < max_rcpt;
2380 addr = addr->next)
2381 if (addr->transport_return == PENDING_DEFER)
2382 {
2383 int count;
2384 BOOL no_flush;
2385 uschar * rcpt_addr;
2386
2387 addr->dsn_aware = peer_offered & PEER_OFFERED_DSN
2388 ? dsn_support_yes : dsn_support_no;
2389
2390 address_count++;
2391 no_flush = pipelining_active && (!mua_wrapper || addr->next);
2392
2393 /* Add any DSN flags to the rcpt command and add to the sent string */
2394
2395 p = buffer;
2396 *p = 0;
2397
2398 if (peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2399 {
2400 if (addr->dsn_flags & rf_dsnflags)
2401 {
2402 int i;
2403 BOOL first = TRUE;
2404 Ustrcpy(p, " NOTIFY=");
2405 while (*p) p++;
2406 for (i = 0; i < 4; i++)
2407 if ((addr->dsn_flags & rf_list[i]) != 0)
2408 {
2409 if (!first) *p++ = ',';
2410 first = FALSE;
2411 Ustrcpy(p, rf_names[i]);
2412 while (*p) p++;
2413 }
2414 }
2415
2416 if (addr->dsn_orcpt)
2417 {
2418 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2419 addr->dsn_orcpt);
2420 while (*p) p++;
2421 }
2422 }
2423
2424 /* Now send the RCPT command, and process outstanding responses when
2425 necessary. After a timeout on RCPT, we just end the function, leaving the
2426 yield as OK, because this error can often mean that there is a problem with
2427 just one address, so we don't want to delay the host. */
2428
2429 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2430
2431 #ifdef SUPPORT_I18N
2432 {
2433 uschar * dummy_errstr;
2434 if ( testflag(addrlist, af_utf8_downcvt)
2435 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2436 dummy_errstr
2437 ) )
2438 {
2439 errno = ERRNO_EXPANDFAIL;
2440 goto SEND_FAILED;
2441 }
2442 }
2443 #endif
2444
2445 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2446 rcpt_addr, igquotstr, buffer);
2447
2448 if (count < 0) goto SEND_FAILED;
2449 if (count > 0)
2450 {
2451 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2452 &sync_addr, host, count, ob->address_retry_include_sender,
2453 lflags.pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2454 sizeof(buffer)))
2455 {
2456 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2457 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2458 break;
2459
2460 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2461 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2462 case 0: /* No 2xx or 5xx, but no probs */
2463 break;
2464
2465 case -1: goto END_OFF; /* Timeout on RCPT */
2466 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2467 }
2468 lflags.pending_MAIL = FALSE; /* Dealt with MAIL */
2469 }
2470 } /* Loop for next address */
2471
2472 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2473 permanently or temporarily. We should have flushed and synced after the last
2474 RCPT. */
2475
2476 if (mua_wrapper)
2477 {
2478 address_item *badaddr;
2479 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2480 if (badaddr->transport_return != PENDING_OK)
2481 {
2482 /*XXX could we find a better errno than 0 here? */
2483 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2484 testflag(badaddr, af_pass_message));
2485 lflags.ok = FALSE;
2486 break;
2487 }
2488 }
2489
2490 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2491 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2492 have a good recipient buffered up if we are pipelining. We don't want to waste
2493 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2494 are pipelining. The responses are all handled by sync_responses().
2495 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2496 to send is. */
2497
2498 if ( !(peer_offered & PEER_OFFERED_CHUNKING)
2499 && (lflags.ok || (pipelining_active && !mua_wrapper)))
2500 {
2501 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2502
2503 if (count < 0) goto SEND_FAILED;
2504 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2505 host, count, ob->address_retry_include_sender, lflags.pending_MAIL,
2506 lflags.ok ? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2507 {
2508 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2509 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2510 break;
2511
2512 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2513 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2514 case 0: break; /* No 2xx or 5xx, but no probs */
2515
2516 case -1: goto END_OFF; /* Timeout on RCPT */
2517 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2518 }
2519 pipelining_active = FALSE;
2520 data_command = string_copy(big_buffer); /* Save for later error message */
2521 }
2522
2523 /* If there were no good recipients (but otherwise there have been no
2524 problems), just set ok TRUE, since we have handled address-specific errors
2525 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2526 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2527 well as body. Set the appropriate timeout value to be used for each chunk.
2528 (Haven't been able to make it work using select() for writing yet.) */
2529
2530 if (!(peer_offered & PEER_OFFERED_CHUNKING) && !lflags.ok)
2531 {
2532 /* Save the first address of the next batch. */
2533 first_addr = addr;
2534
2535 lflags.ok = TRUE;
2536 }
2537 else
2538 {
2539 transport_ctx tctx = {
2540 tblock,
2541 addrlist,
2542 US".", US"..", /* Escaping strings */
2543 topt_use_crlf | topt_escape_headers
2544 | (tblock->body_only ? topt_no_headers : 0)
2545 | (tblock->headers_only ? topt_no_body : 0)
2546 | (tblock->return_path_add ? topt_add_return_path : 0)
2547 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2548 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2549 };
2550
2551 /* If using CHUNKING we need a callback from the generic transport
2552 support to us, for the sending of BDAT smtp commands and the reaping
2553 of responses. The callback needs a whole bunch of state so set up
2554 a transport-context structure to be passed around. */
2555
2556 if (peer_offered & PEER_OFFERED_CHUNKING)
2557 {
2558 tctx.check_string = tctx.escape_string = NULL;
2559 tctx.options |= topt_use_bdat;
2560 tctx.chunk_cb = smtp_chunk_cmd_callback;
2561 tctx.inblock = &inblock;
2562 tctx.outblock = &outblock;
2563 tctx.host = host;
2564 tctx.first_addr = first_addr;
2565 tctx.sync_addr = &sync_addr;
2566 tctx.pending_MAIL = lflags.pending_MAIL;
2567 tctx.pending_BDAT = FALSE;
2568 tctx.good_RCPT = lflags.ok;
2569 tctx.completed_address = &completed_address;
2570 tctx.cmd_count = 0;
2571 tctx.buffer = buffer;
2572 }
2573 else
2574 tctx.options |= topt_end_dot;
2575
2576 /* Save the first address of the next batch. */
2577 first_addr = addr;
2578
2579 /* Responses from CHUNKING commands go in buffer. Otherwise,
2580 there has not been a response. */
2581
2582 buffer[0] = 0;
2583
2584 sigalrm_seen = FALSE;
2585 transport_write_timeout = ob->data_timeout;
2586 smtp_command = US"sending data block"; /* For error messages */
2587 DEBUG(D_transport|D_v)
2588 if (peer_offered & PEER_OFFERED_CHUNKING)
2589 debug_printf(" will write message using CHUNKING\n");
2590 else
2591 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2592 transport_count = 0;
2593
2594 #ifndef DISABLE_DKIM
2595 lflags.ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2596 #else
2597 lflags.ok = transport_write_message(inblock.sock, &tctx, 0);
2598 #endif
2599
2600 /* transport_write_message() uses write() because it is called from other
2601 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2602 it can exit with "Broken pipe" as its error. This really means that the
2603 socket got closed at the far end. */
2604
2605 transport_write_timeout = 0; /* for subsequent transports */
2606
2607 /* Failure can either be some kind of I/O disaster (including timeout),
2608 or the failure of a transport filter or the expansion of added headers.
2609 Or, when CHUNKING, it can be a protocol-detected failure. */
2610
2611 if (!lflags.ok)
2612 goto RESPONSE_FAILED;
2613
2614 /* We used to send the terminating "." explicitly here, but because of
2615 buffering effects at both ends of TCP/IP connections, you don't gain
2616 anything by keeping it separate, so it might as well go in the final
2617 data buffer for efficiency. This is now done by setting the topt_end_dot
2618 flag above. */
2619
2620 smtp_command = US"end of data";
2621
2622 if (peer_offered & PEER_OFFERED_CHUNKING && tctx.cmd_count > 1)
2623 {
2624 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2625 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2626 host, tctx.cmd_count-1, ob->address_retry_include_sender,
2627 lflags.pending_MAIL, 0,
2628 &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2629 {
2630 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2631 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2632 break;
2633
2634 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2635 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2636 case 0: break; /* No 2xx or 5xx, but no probs */
2637
2638 case -1: goto END_OFF; /* Timeout on RCPT */
2639 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2640 }
2641 }
2642
2643 #ifndef DISABLE_PRDR
2644 /* For PRDR we optionally get a partial-responses warning
2645 * followed by the individual responses, before going on with
2646 * the overall response. If we don't get the warning then deal
2647 * with per non-PRDR. */
2648 if(lflags.prdr_active)
2649 {
2650 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2651 ob->final_timeout);
2652 if (!lflags.ok && errno == 0) switch(buffer[0])
2653 {
2654 case '2': lflags.prdr_active = FALSE;
2655 lflags.ok = TRUE;
2656 break;
2657 case '4': errno = ERRNO_DATA4XX;
2658 addrlist->more_errno |=
2659 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2660 break;
2661 }
2662 }
2663 else
2664 #endif
2665
2666 /* For non-PRDR SMTP, we now read a single response that applies to the
2667 whole message. If it is OK, then all the addresses have been delivered. */
2668
2669 if (!lflags.lmtp)
2670 {
2671 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2672 ob->final_timeout);
2673 if (!lflags.ok && errno == 0 && buffer[0] == '4')
2674 {
2675 errno = ERRNO_DATA4XX;
2676 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2677 }
2678 }
2679
2680 /* For LMTP, we get back a response for every RCPT command that we sent;
2681 some may be accepted and some rejected. For those that get a response, their
2682 status is fixed; any that are accepted have been handed over, even if later
2683 responses crash - at least, that's how I read RFC 2033.
2684
2685 If all went well, mark the recipient addresses as completed, record which
2686 host/IPaddress they were delivered to, and cut out RSET when sending another
2687 message down the same channel. Write the completed addresses to the journal
2688 now so that they are recorded in case there is a crash of hardware or
2689 software before the spool gets updated. Also record the final SMTP
2690 confirmation if needed (for SMTP only). */
2691
2692 if (lflags.ok)
2693 {
2694 int flag = '=';
2695 int delivery_time = (int)(time(NULL) - start_delivery_time);
2696 int len;
2697 uschar *conf = NULL;
2698
2699 lflags.send_rset = FALSE;
2700 pipelining_active = FALSE;
2701
2702 /* Set up confirmation if needed - applies only to SMTP */
2703
2704 if (
2705 #ifdef DISABLE_EVENT
2706 LOGGING(smtp_confirmation) &&
2707 #endif
2708 !lflags.lmtp
2709 )
2710 {
2711 const uschar *s = string_printing(buffer);
2712 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2713 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2714 }
2715
2716 /* Process all transported addresses - for LMTP or PRDR, read a status for
2717 each one. */
2718
2719 for (addr = addrlist; addr != first_addr; addr = addr->next)
2720 {
2721 if (addr->transport_return != PENDING_OK) continue;
2722
2723 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2724 remaining addresses. Otherwise, it's a return code for just the one
2725 address. For temporary errors, add a retry item for the address so that
2726 it doesn't get tried again too soon. */
2727
2728 #ifndef DISABLE_PRDR
2729 if (lflags.lmtp || lflags.prdr_active)
2730 #else
2731 if (lflags.lmtp)
2732 #endif
2733 {
2734 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2735 ob->final_timeout))
2736 {
2737 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2738 addr->message = string_sprintf(
2739 #ifndef DISABLE_PRDR
2740 "%s error after %s: %s", lflags.prdr_active ? "PRDR":"LMTP",
2741 #else
2742 "LMTP error after %s: %s",
2743 #endif
2744 data_command, string_printing(buffer));
2745 setflag(addr, af_pass_message); /* Allow message to go to user */
2746 if (buffer[0] == '5')
2747 addr->transport_return = FAIL;
2748 else
2749 {
2750 errno = ERRNO_DATA4XX;
2751 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2752 addr->transport_return = DEFER;
2753 #ifndef DISABLE_PRDR
2754 if (!lflags.prdr_active)
2755 #endif
2756 retry_add_item(addr, addr->address_retry_key, 0);
2757 }
2758 continue;
2759 }
2760 completed_address = TRUE; /* NOW we can set this flag */
2761 if (LOGGING(smtp_confirmation))
2762 {
2763 const uschar *s = string_printing(buffer);
2764 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2765 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2766 }
2767 }
2768
2769 /* SMTP, or success return from LMTP for this address. Pass back the
2770 actual host that was used. */
2771
2772 addr->transport_return = OK;
2773 addr->more_errno = delivery_time;
2774 addr->host_used = host;
2775 addr->special_action = flag;
2776 addr->message = conf;
2777 #ifndef DISABLE_PRDR
2778 if (lflags.prdr_active) addr->flags |= af_prdr_used;
2779 #endif
2780 if (peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
2781 flag = '-';
2782
2783 #ifndef DISABLE_PRDR
2784 if (!lflags.prdr_active)
2785 #endif
2786 {
2787 /* Update the journal. For homonymic addresses, use the base address plus
2788 the transport name. See lots of comments in deliver.c about the reasons
2789 for the complications when homonyms are involved. Just carry on after
2790 write error, as it may prove possible to update the spool file later. */
2791
2792 if (testflag(addr, af_homonym))
2793 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2794 else
2795 sprintf(CS buffer, "%.500s\n", addr->unique);
2796
2797 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2798 len = Ustrlen(CS buffer);
2799 if (write(journal_fd, buffer, len) != len)
2800 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2801 "%s: %s", buffer, strerror(errno));
2802 }
2803 }
2804
2805 #ifndef DISABLE_PRDR
2806 if (lflags.prdr_active)
2807 {
2808 /* PRDR - get the final, overall response. For any non-success
2809 upgrade all the address statuses. */
2810 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2811 ob->final_timeout);
2812 if (!lflags.ok)
2813 {
2814 if(errno == 0 && buffer[0] == '4')
2815 {
2816 errno = ERRNO_DATA4XX;
2817 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2818 }
2819 for (addr = addrlist; addr != first_addr; addr = addr->next)
2820 if (buffer[0] == '5' || addr->transport_return == OK)
2821 addr->transport_return = PENDING_OK; /* allow set_errno action */
2822 goto RESPONSE_FAILED;
2823 }
2824
2825 /* Update the journal, or setup retry. */
2826 for (addr = addrlist; addr != first_addr; addr = addr->next)
2827 if (addr->transport_return == OK)
2828 {
2829 if (testflag(addr, af_homonym))
2830 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2831 else
2832 sprintf(CS buffer, "%.500s\n", addr->unique);
2833
2834 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2835 len = Ustrlen(CS buffer);
2836 if (write(journal_fd, buffer, len) != len)
2837 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2838 "%s: %s", buffer, strerror(errno));
2839 }
2840 else if (addr->transport_return == DEFER)
2841 retry_add_item(addr, addr->address_retry_key, -2);
2842 }
2843 #endif
2844
2845 /* Ensure the journal file is pushed out to disk. */
2846
2847 if (EXIMfsync(journal_fd) < 0)
2848 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2849 strerror(errno));
2850 }
2851 }
2852
2853
2854 /* Handle general (not specific to one address) failures here. The value of ok
2855 is used to skip over this code on the falling through case. A timeout causes a
2856 deferral. Other errors may defer or fail according to the response code, and
2857 may set up a special errno value, e.g. after connection chopped, which is
2858 assumed if errno == 0 and there is no text in the buffer. If control reaches
2859 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2860 the problem is not related to this specific message. */
2861
2862 if (!lflags.ok)
2863 {
2864 int code, set_rc;
2865 uschar * set_message;
2866
2867 RESPONSE_FAILED:
2868 {
2869 save_errno = errno;
2870 message = NULL;
2871 lflags.send_quit = check_response(host, &save_errno, addrlist->more_errno,
2872 buffer, &code, &message, &pass_message);
2873 goto FAILED;
2874 }
2875
2876 SEND_FAILED:
2877 {
2878 save_errno = errno;
2879 code = '4';
2880 message = US string_sprintf("send() to %s [%s] failed: %s",
2881 host->name, host->address, strerror(save_errno));
2882 lflags.send_quit = FALSE;
2883 goto FAILED;
2884 }
2885
2886 /* This label is jumped to directly when a TLS negotiation has failed,
2887 or was not done for a host for which it is required. Values will be set
2888 in message and save_errno, and setting_up will always be true. Treat as
2889 a temporary error. */
2890
2891 #ifdef SUPPORT_TLS
2892 TLS_FAILED:
2893 code = '4';
2894 #endif
2895
2896 /* If the failure happened while setting up the call, see if the failure was
2897 a 5xx response (this will either be on connection, or following HELO - a 5xx
2898 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2899 never going to accept them. For other errors during setting up (timeouts or
2900 whatever), defer all addresses, and yield DEFER, so that the host is not
2901 tried again for a while. */
2902
2903 FAILED:
2904 lflags.ok = FALSE; /* For when reached by GOTO */
2905 set_message = message;
2906
2907 if (lflags.setting_up)
2908 if (code == '5')
2909 set_rc = FAIL;
2910 else
2911 yield = set_rc = DEFER;
2912
2913 /* We want to handle timeouts after MAIL or "." and loss of connection after
2914 "." specially. They can indicate a problem with the sender address or with
2915 the contents of the message rather than a real error on the connection. These
2916 cases are treated in the same way as a 4xx response. This next bit of code
2917 does the classification. */
2918
2919 else
2920 {
2921 BOOL message_error;
2922
2923 switch(save_errno)
2924 {
2925 #ifdef SUPPORT_I18N
2926 case ERRNO_UTF8_FWD:
2927 code = '5';
2928 /*FALLTHROUGH*/
2929 #endif
2930 case 0:
2931 case ERRNO_MAIL4XX:
2932 case ERRNO_DATA4XX:
2933 message_error = TRUE;
2934 break;
2935
2936 case ETIMEDOUT:
2937 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2938 Ustrncmp(smtp_command,"end ",4) == 0;
2939 break;
2940
2941 case ERRNO_SMTPCLOSED:
2942 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2943 break;
2944
2945 default:
2946 message_error = FALSE;
2947 break;
2948 }
2949
2950 /* Handle the cases that are treated as message errors. These are:
2951
2952 (a) negative response or timeout after MAIL
2953 (b) negative response after DATA
2954 (c) negative response or timeout or dropped connection after "."
2955 (d) utf8 support required and not offered
2956
2957 It won't be a negative response or timeout after RCPT, as that is dealt
2958 with separately above. The action in all cases is to set an appropriate
2959 error code for all the addresses, but to leave yield set to OK because the
2960 host itself has not failed. Of course, it might in practice have failed
2961 when we've had a timeout, but if so, we'll discover that at the next
2962 delivery attempt. For a temporary error, set the message_defer flag, and
2963 write to the logs for information if this is not the last host. The error
2964 for the last host will be logged as part of the address's log line. */
2965
2966 if (message_error)
2967 {
2968 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2969
2970 /* If there's an errno, the message contains just the identity of
2971 the host. */
2972
2973 if (code == '5')
2974 set_rc = FAIL;
2975 else /* Anything other than 5 is treated as temporary */
2976 {
2977 set_rc = DEFER;
2978 if (save_errno > 0)
2979 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2980 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2981 msglog_line(host, message);
2982 *message_defer = TRUE;
2983 }
2984 }
2985
2986 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2987 ".", or some other transportation error. We defer all addresses and yield
2988 DEFER, except for the case of failed add_headers expansion, or a transport
2989 filter failure, when the yield should be ERROR, to stop it trying other
2990 hosts. */
2991
2992 else
2993 {
2994 set_rc = DEFER;
2995 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2996 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2997 }
2998 }
2999
3000 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3001 #ifdef EXPERIMENTAL_DSN_INFO
3002 , smtp_greeting, helo_response
3003 #endif
3004 );
3005 }
3006
3007
3008 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3009 SMTP session tidily. However, if there were too many addresses to send in one
3010 message (indicated by first_addr being non-NULL) we want to carry on with the
3011 rest of them. Also, it is desirable to send more than one message down the SMTP
3012 connection if there are several waiting, provided we haven't already sent so
3013 many as to hit the configured limit. The function transport_check_waiting looks
3014 for a waiting message and returns its id. Then transport_pass_socket tries to
3015 set up a continued delivery by passing the socket on to another process. The
3016 variable send_rset is FALSE if a message has just been successfully transfered.
3017
3018 If we are already sending down a continued channel, there may be further
3019 addresses not yet delivered that are aimed at the same host, but which have not
3020 been passed in this run of the transport. In this case, continue_more will be
3021 true, and all we should do is send RSET if necessary, and return, leaving the
3022 channel open.
3023
3024 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3025 do not want to continue with other messages down the same channel, because that
3026 can lead to looping between two or more messages, all with the same,
3027 temporarily failing address(es). [The retry information isn't updated yet, so
3028 new processes keep on trying.] We probably also don't want to try more of this
3029 message's addresses either.
3030
3031 If we have started a TLS session, we have to end it before passing the
3032 connection to a new process. However, not all servers can handle this (Exim
3033 can), so we do not pass such a connection on if the host matches
3034 hosts_nopass_tls. */
3035
3036 DEBUG(D_transport)
3037 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3038 "yield=%d first_address is %sNULL\n", lflags.ok, lflags.send_quit,
3039 lflags.send_rset, continue_more, yield, first_addr ? "not " : "");
3040
3041 if (completed_address && lflags.ok && lflags.send_quit)
3042 {
3043 BOOL more;
3044 smtp_compare_t t_compare;
3045
3046 t_compare.tblock = tblock;
3047 t_compare.current_sender_address = sender_address;
3048
3049 if ( first_addr != NULL
3050 || continue_more
3051 || ( ( tls_out.active < 0
3052 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
3053 )
3054 &&
3055 transport_check_waiting(tblock->name, host->name,
3056 tblock->connection_max_messages, new_message_id, &more,
3057 (oicf)smtp_are_same_identities, (void*)&t_compare)
3058 ) )
3059 {
3060 uschar *msg;
3061 BOOL pass_message;
3062
3063 if (lflags.send_rset)
3064 {
3065 if (! (lflags.ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
3066 {
3067 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3068 host->address, strerror(save_errno));
3069 lflags.send_quit = FALSE;
3070 }
3071 else if (! (lflags.ok = smtp_read_response(&inblock, buffer,
3072 sizeof(buffer), '2', ob->command_timeout)))
3073 {
3074 int code;
3075 lflags.send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
3076 &pass_message);
3077 if (!lflags.send_quit)
3078 {
3079 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3080 host->name, host->address, msg);
3081 }
3082 }
3083 }
3084
3085 /* Either RSET was not needed, or it succeeded */
3086
3087 if (lflags.ok)
3088 {
3089 if (first_addr != NULL) /* More addresses still to be sent */
3090 { /* in this run of the transport */
3091 continue_sequence++; /* Causes * in logging */
3092 goto SEND_MESSAGE;
3093 }
3094 if (continue_more) return yield; /* More addresses for another run */
3095
3096 /* Pass the socket to a new Exim process. Before doing so, we must shut
3097 down TLS. Not all MTAs allow for the continuation of the SMTP session
3098 when TLS is shut down. We test for this by sending a new EHLO. If we
3099 don't get a good response, we don't attempt to pass the socket on. */
3100
3101 #ifdef SUPPORT_TLS
3102 if (tls_out.active >= 0)
3103 {
3104 tls_close(FALSE, TRUE);
3105 smtp_peer_options = smtp_peer_options_wrap;
3106 if (lflags.smtps)
3107 lflags.ok = FALSE;
3108 else
3109 lflags.ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
3110 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3111 ob->command_timeout);
3112 }
3113 #endif
3114
3115 /* If the socket is successfully passed, we musn't send QUIT (or
3116 indeed anything!) from here. */
3117
3118 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3119 propagate it from the initial
3120 */
3121 if (lflags.ok && transport_pass_socket(tblock->name, host->name,
3122 host->address, new_message_id, inblock.sock))
3123 lflags.send_quit = FALSE;
3124 }
3125
3126 /* If RSET failed and there are addresses left, they get deferred. */
3127
3128 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
3129 #ifdef EXPERIMENTAL_DSN_INFO
3130 , smtp_greeting, helo_response
3131 #endif
3132 );
3133 }
3134 }
3135
3136 /* End off tidily with QUIT unless the connection has died or the socket has
3137 been passed to another process. There has been discussion on the net about what
3138 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3139 to wait for a response, but on the other hand, there isn't anything one can do
3140 with an error response, other than log it. Exim used to do that. However,
3141 further discussion suggested that it is positively advantageous not to wait for
3142 the response, but to close the session immediately. This is supposed to move
3143 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3144 load from the server. (Hosts that are both servers and clients may not see much
3145 difference, of course.) Further discussion indicated that this was safe to do
3146 on Unix systems which have decent implementations of TCP/IP that leave the
3147 connection around for a while (TIME_WAIT) after the application has gone away.
3148 This enables the response sent by the server to be properly ACKed rather than
3149 timed out, as can happen on broken TCP/IP implementations on other OS.
3150
3151 This change is being made on 31-Jul-98. After over a year of trouble-free
3152 operation, the old commented-out code was removed on 17-Sep-99. */
3153
3154 SEND_QUIT:
3155 if (lflags.send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3156
3157 END_OFF:
3158
3159 #ifdef SUPPORT_TLS
3160 tls_close(FALSE, TRUE);
3161 #endif
3162
3163 /* Close the socket, and return the appropriate value, first setting
3164 works because the NULL setting is passed back to the calling process, and
3165 remote_max_parallel is forced to 1 when delivering over an existing connection,
3166
3167 If all went well and continue_more is set, we shouldn't actually get here if
3168 there are further addresses, as the return above will be taken. However,
3169 writing RSET might have failed, or there may be other addresses whose hosts are
3170 specified in the transports, and therefore not visible at top level, in which
3171 case continue_more won't get set. */
3172
3173 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
3174 if (lflags.send_quit)
3175 {
3176 shutdown(outblock.sock, SHUT_WR);
3177 if (fcntl(inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3178 for (rc = 16; read(inblock.sock, inbuffer, sizeof(inbuffer)) > 0 && rc > 0;)
3179 rc--; /* drain socket */
3180 }
3181 (void)close(inblock.sock);
3182
3183 #ifndef DISABLE_EVENT
3184 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3185 #endif
3186
3187 continue_transport = NULL;
3188 continue_hostname = NULL;
3189 return yield;
3190 }
3191
3192
3193
3194
3195 /*************************************************
3196 * Closedown entry point *
3197 *************************************************/
3198
3199 /* This function is called when exim is passed an open smtp channel
3200 from another incarnation, but the message which it has been asked
3201 to deliver no longer exists. The channel is on stdin.
3202
3203 We might do fancy things like looking for another message to send down
3204 the channel, but if the one we sought has gone, it has probably been
3205 delivered by some other process that itself will seek further messages,
3206 so just close down our connection.
3207
3208 Argument: pointer to the transport instance block
3209 Returns: nothing
3210 */
3211
3212 void
3213 smtp_transport_closedown(transport_instance *tblock)
3214 {
3215 smtp_transport_options_block *ob =
3216 (smtp_transport_options_block *)(tblock->options_block);
3217 smtp_inblock inblock;
3218 smtp_outblock outblock;
3219 uschar buffer[256];
3220 uschar inbuffer[4096];
3221 uschar outbuffer[16];
3222
3223 inblock.sock = fileno(stdin);
3224 inblock.buffer = inbuffer;
3225 inblock.buffersize = sizeof(inbuffer);
3226 inblock.ptr = inbuffer;
3227 inblock.ptrend = inbuffer;
3228
3229 outblock.sock = inblock.sock;
3230 outblock.buffersize = sizeof(outbuffer);
3231 outblock.buffer = outbuffer;
3232 outblock.ptr = outbuffer;
3233 outblock.cmd_count = 0;
3234 outblock.authenticating = FALSE;
3235
3236 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3237 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3238 ob->command_timeout);
3239 (void)close(inblock.sock);
3240 }
3241
3242
3243
3244 /*************************************************
3245 * Prepare addresses for delivery *
3246 *************************************************/
3247
3248 /* This function is called to flush out error settings from previous delivery
3249 attempts to other hosts. It also records whether we got here via an MX record
3250 or not in the more_errno field of the address. We are interested only in
3251 addresses that are still marked DEFER - others may have got delivered to a
3252 previously considered IP address. Set their status to PENDING_DEFER to indicate
3253 which ones are relevant this time.
3254
3255 Arguments:
3256 addrlist the list of addresses
3257 host the host we are delivering to
3258
3259 Returns: the first address for this delivery
3260 */
3261
3262 static address_item *
3263 prepare_addresses(address_item *addrlist, host_item *host)
3264 {
3265 address_item *first_addr = NULL;
3266 address_item *addr;
3267 for (addr = addrlist; addr; addr = addr->next)
3268 if (addr->transport_return == DEFER)
3269 {
3270 if (!first_addr) first_addr = addr;
3271 addr->transport_return = PENDING_DEFER;
3272 addr->basic_errno = 0;
3273 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3274 addr->message = NULL;
3275 #ifdef SUPPORT_TLS
3276 addr->cipher = NULL;
3277 addr->ourcert = NULL;
3278 addr->peercert = NULL;
3279 addr->peerdn = NULL;
3280 addr->ocsp = OCSP_NOT_REQ;
3281 #endif
3282 #ifdef EXPERIMENTAL_DSN_INFO
3283 addr->smtp_greeting = NULL;
3284 addr->helo_response = NULL;
3285 #endif
3286 }
3287 return first_addr;
3288 }
3289
3290
3291
3292 /*************************************************
3293 * Main entry point *
3294 *************************************************/
3295
3296 /* See local README for interface details. As this is a remote transport, it is
3297 given a chain of addresses to be delivered in one connection, if possible. It
3298 always returns TRUE, indicating that each address has its own independent
3299 status set, except if there is a setting up problem, in which case it returns
3300 FALSE. */
3301
3302 BOOL
3303 smtp_transport_entry(
3304 transport_instance *tblock, /* data for this instantiation */
3305 address_item *addrlist) /* addresses we are working on */
3306 {
3307 int cutoff_retry;
3308 int port;
3309 int hosts_defer = 0;
3310 int hosts_fail = 0;
3311 int hosts_looked_up = 0;
3312 int hosts_retry = 0;
3313 int hosts_serial = 0;
3314 int hosts_total = 0;
3315 int total_hosts_tried = 0;
3316 address_item *addr;
3317 BOOL expired = TRUE;
3318 uschar *expanded_hosts = NULL;
3319 uschar *pistring;
3320 uschar *tid = string_sprintf("%s transport", tblock->name);
3321 smtp_transport_options_block *ob =
3322 (smtp_transport_options_block *)(tblock->options_block);
3323 host_item *hostlist = addrlist->host_list;
3324 host_item *host = NULL;
3325
3326 DEBUG(D_transport)
3327 {
3328 debug_printf("%s transport entered\n", tblock->name);
3329 for (addr = addrlist; addr; addr = addr->next)
3330 debug_printf(" %s\n", addr->address);
3331 if (hostlist)
3332 {
3333 debug_printf("hostlist:\n");
3334 for (host = hostlist; host; host = host->next)
3335 debug_printf(" %s:%d\n", host->name, host->port);
3336 }
3337 if (continue_hostname) debug_printf("already connected to %s [%s]\n",
3338 continue_hostname, continue_host_address);
3339 }
3340
3341 /* Set the flag requesting that these hosts be added to the waiting
3342 database if the delivery fails temporarily or if we are running with
3343 queue_smtp or a 2-stage queue run. This gets unset for certain
3344 kinds of error, typically those that are specific to the message. */
3345
3346 update_waiting = TRUE;
3347
3348 /* If a host list is not defined for the addresses - they must all have the
3349 same one in order to be passed to a single transport - or if the transport has
3350 a host list with hosts_override set, use the host list supplied with the
3351 transport. It is an error for this not to exist. */
3352
3353 if (!hostlist || (ob->hosts_override && ob->hosts))
3354 {
3355 if (!ob->hosts)
3356 {
3357 addrlist->message = string_sprintf("%s transport called with no hosts set",
3358 tblock->name);
3359 addrlist->transport_return = PANIC;
3360 return FALSE; /* Only top address has status */
3361 }
3362
3363 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3364 ob->hosts);
3365
3366 /* If the transport's host list contains no '$' characters, and we are not
3367 randomizing, it is fixed and therefore a chain of hosts can be built once
3368 and for all, and remembered for subsequent use by other calls to this
3369 transport. If, on the other hand, the host list does contain '$', or we are
3370 randomizing its order, we have to rebuild it each time. In the fixed case,
3371 as the hosts string will never be used again, it doesn't matter that we
3372 replace all the : characters with zeros. */
3373
3374 if (!ob->hostlist)
3375 {
3376 uschar *s = ob->hosts;
3377
3378 if (Ustrchr(s, '$') != NULL)
3379 {
3380 if (!(expanded_hosts = expand_string(s)))
3381 {
3382 addrlist->message = string_sprintf("failed to expand list of hosts "
3383 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3384 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3385 return FALSE; /* Only top address has status */
3386 }
3387 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3388 "\"%s\"\n", s, expanded_hosts);
3389 s = expanded_hosts;
3390 }
3391 else
3392 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3393
3394 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3395
3396 /* Check that the expansion yielded something useful. */
3397 if (!hostlist)
3398 {
3399 addrlist->message =
3400 string_sprintf("%s transport has empty hosts setting", tblock->name);
3401 addrlist->transport_return = PANIC;
3402 return FALSE; /* Only top address has status */
3403 }
3404
3405 /* If there was no expansion of hosts, save the host list for
3406 next time. */
3407
3408 if (!expanded_hosts) ob->hostlist = hostlist;
3409 }
3410
3411 /* This is not the first time this transport has been run in this delivery;
3412 the host list was built previously. */
3413
3414 else
3415 hostlist = ob->hostlist;
3416 }
3417
3418 /* The host list was supplied with the address. If hosts_randomize is set, we
3419 must sort it into a random order if it did not come from MX records and has not
3420 already been randomized (but don't bother if continuing down an existing
3421 connection). */
3422
3423 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3424 {
3425 host_item *newlist = NULL;
3426 while (hostlist)
3427 {
3428 host_item *h = hostlist;
3429 hostlist = hostlist->next;
3430
3431 h->sort_key = random_number(100);
3432
3433 if (!newlist)
3434 {
3435 h->next = NULL;
3436 newlist = h;
3437 }
3438 else if (h->sort_key < newlist->sort_key)
3439 {
3440 h->next = newlist;
3441 newlist = h;
3442 }
3443 else
3444 {
3445 host_item *hh = newlist;
3446 while (hh->next)
3447 {
3448 if (h->sort_key < hh->next->sort_key) break;
3449 hh = hh->next;
3450 }
3451 h->next = hh->next;
3452 hh->next = h;
3453 }
3454 }
3455
3456 hostlist = addrlist->host_list = newlist;
3457 }
3458
3459 /* Sort out the default port. */
3460
3461 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3462
3463 /* For each host-plus-IP-address on the list:
3464
3465 . If this is a continued delivery and the host isn't the one with the
3466 current connection, skip.
3467
3468 . If the status is unusable (i.e. previously failed or retry checked), skip.
3469
3470 . If no IP address set, get the address, either by turning the name into
3471 an address, calling gethostbyname if gethostbyname is on, or by calling
3472 the DNS. The DNS may yield multiple addresses, in which case insert the
3473 extra ones into the list.
3474
3475 . Get the retry data if not previously obtained for this address and set the
3476 field which remembers the state of this address. Skip if the retry time is
3477 not reached. If not, remember whether retry data was found. The retry string
3478 contains both the name and the IP address.
3479
3480 . Scan the list of addresses and mark those whose status is DEFER as
3481 PENDING_DEFER. These are the only ones that will be processed in this cycle
3482 of the hosts loop.
3483
3484 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3485 Some addresses may be successfully delivered, others may fail, and yet
3486 others may get temporary errors and so get marked DEFER.
3487
3488 . The return from the delivery attempt is OK if a connection was made and a
3489 valid SMTP dialogue was completed. Otherwise it is DEFER.
3490
3491 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3492
3493 . If fail to connect, or other defer state, add a retry item.
3494
3495 . If there are any addresses whose status is still DEFER, carry on to the
3496 next host/IPaddress, unless we have tried the number of hosts given
3497 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3498 there is some fancy logic for hosts_max_try that means its limit can be
3499 overstepped in some circumstances.
3500
3501 If we get to the end of the list, all hosts have deferred at least one address,
3502 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3503 delivery attempt to those hosts whose last try was before the arrival time of
3504 the current message. To cope with this, we have to go round the loop a second
3505 time. After that, set the status and error data for any addresses that haven't
3506 had it set already. */
3507
3508 for (cutoff_retry = 0;
3509 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3510 cutoff_retry++)
3511 {
3512 host_item *nexthost = NULL;
3513 int unexpired_hosts_tried = 0;
3514
3515 for (host = hostlist;
3516 host
3517 && unexpired_hosts_tried < ob->hosts_max_try
3518 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3519 host = nexthost)
3520 {
3521 int rc;
3522 int host_af;
3523 uschar *rs;
3524 BOOL host_is_expired = FALSE;
3525 BOOL message_defer = FALSE;
3526 BOOL some_deferred = FALSE;
3527 address_item *first_addr = NULL;
3528 uschar *interface = NULL;
3529 uschar *retry_host_key = NULL;
3530 uschar *retry_message_key = NULL;
3531 uschar *serialize_key = NULL;
3532
3533 /* Default next host is next host. :-) But this can vary if the
3534 hosts_max_try limit is hit (see below). It may also be reset if a host
3535 address is looked up here (in case the host was multihomed). */
3536
3537 nexthost = host->next;
3538
3539 /* If the address hasn't yet been obtained from the host name, look it up
3540 now, unless the host is already marked as unusable. If it is marked as
3541 unusable, it means that the router was unable to find its IP address (in
3542 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3543 the lookup failed last time. We don't get this far if *all* MX records
3544 point to non-existent hosts; that is treated as a hard error.
3545
3546 We can just skip this host entirely. When the hosts came from the router,
3547 the address will timeout based on the other host(s); when the address is
3548 looked up below, there is an explicit retry record added.
3549
3550 Note that we mustn't skip unusable hosts if the address is not unset; they
3551 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3552
3553 if (!host->address)
3554 {
3555 int new_port, flags;
3556 host_item *hh;
3557
3558 if (host->status >= hstatus_unusable)
3559 {
3560 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3561 host->name);
3562 continue;
3563 }
3564
3565 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3566
3567 /* The host name is permitted to have an attached port. Find it, and
3568 strip it from the name. Just remember it for now. */
3569
3570 new_port = host_item_get_port(host);
3571
3572 /* Count hosts looked up */
3573
3574 hosts_looked_up++;
3575
3576 /* Find by name if so configured, or if it's an IP address. We don't
3577 just copy the IP address, because we need the test-for-local to happen. */
3578
3579 flags = HOST_FIND_BY_A;
3580 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3581 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3582
3583 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3584 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3585 else
3586 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3587 &ob->dnssec, /* domains for request/require */
3588 NULL, NULL);
3589
3590 /* Update the host (and any additional blocks, resulting from
3591 multihoming) with a host-specific port, if any. */
3592
3593 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3594
3595 /* Failure to find the host at this time (usually DNS temporary failure)
3596 is really a kind of routing failure rather than a transport failure.
3597 Therefore we add a retry item of the routing kind, not to stop us trying
3598 to look this name up here again, but to ensure the address gets timed
3599 out if the failures go on long enough. A complete failure at this point
3600 commonly points to a configuration error, but the best action is still
3601 to carry on for the next host. */
3602
3603 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3604 {
3605 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3606 expired = FALSE;
3607 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3608 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3609 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3610 host->status = hstatus_unusable;
3611
3612 for (addr = addrlist; addr; addr = addr->next)
3613 {
3614 if (addr->transport_return != DEFER) continue;
3615 addr->basic_errno = ERRNO_UNKNOWNHOST;
3616 addr->message =
3617 string_sprintf("failed to lookup IP address for %s", host->name);
3618 }
3619 continue;
3620 }
3621
3622 /* If the host is actually the local host, we may have a problem, or
3623 there may be some cunning configuration going on. In the problem case,
3624 log things and give up. The default transport status is already DEFER. */
3625
3626 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3627 {
3628 for (addr = addrlist; addr; addr = addr->next)
3629 {
3630 addr->basic_errno = 0;
3631 addr->message = string_sprintf("%s transport found host %s to be "
3632 "local", tblock->name, host->name);
3633 }
3634 goto END_TRANSPORT;
3635 }
3636 } /* End of block for IP address lookup */
3637
3638 /* If this is a continued delivery, we are interested only in the host
3639 which matches the name of the existing open channel. The check is put
3640 here after the local host lookup, in case the name gets expanded as a
3641 result of the lookup. Set expired FALSE, to save the outer loop executing
3642 twice. */
3643
3644 if ( continue_hostname
3645 && ( Ustrcmp(continue_hostname, host->name) != 0
3646 || Ustrcmp(continue_host_address, host->address) != 0
3647 ) )
3648 {
3649 expired = FALSE;
3650 continue; /* With next host */
3651 }
3652
3653 /* Reset the default next host in case a multihomed host whose addresses
3654 are not looked up till just above added to the host list. */
3655
3656 nexthost = host->next;
3657
3658 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3659 domain is in queue_smtp_domains, we don't actually want to attempt any
3660 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3661 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3662 were not in it. We don't want to hold up all SMTP deliveries! Except when
3663 doing a two-stage queue run, don't do this if forcing. */
3664
3665 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3666 match_isinlist(addrlist->domain,
3667 (const uschar **)&queue_smtp_domains, 0,
3668 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3669 {
3670 expired = FALSE;
3671 for (addr = addrlist; addr; addr = addr->next)
3672 if (addr->transport_return == DEFER)
3673 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3674 continue; /* With next host */
3675 }
3676
3677 /* Count hosts being considered - purely for an intelligent comment
3678 if none are usable. */
3679
3680 hosts_total++;
3681
3682 /* Set $host and $host address now in case they are needed for the
3683 interface expansion or the serialize_hosts check; they remain set if an
3684 actual delivery happens. */
3685
3686 deliver_host = host->name;
3687 deliver_host_address = host->address;
3688 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3689 : host->dnssec == DS_NO ? US"no"
3690 : US"";
3691
3692 /* Set up a string for adding to the retry key if the port number is not
3693 the standard SMTP port. A host may have its own port setting that overrides
3694 the default. */
3695
3696 pistring = string_sprintf(":%d", host->port == PORT_NONE
3697 ? port : host->port);
3698 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3699
3700 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3701 string is set, even if constant (as different transports can have different
3702 constant settings), we must add it to the key that is used for retries,
3703 because connections to the same host from a different interface should be
3704 treated separately. */
3705
3706 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
3707 if ((rs = ob->interface) && *rs)
3708 {
3709 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3710 return FALSE;
3711 pistring = string_sprintf("%s/%s", pistring, interface);
3712 }
3713
3714 /* The first time round the outer loop, check the status of the host by
3715 inspecting the retry data. The second time round, we are interested only
3716 in expired hosts that haven't been tried since this message arrived. */
3717
3718 if (cutoff_retry == 0)
3719 {
3720 BOOL incl_ip;
3721 /* Ensure the status of the address is set by checking retry data if
3722 necessary. There may be host-specific retry data (applicable to all
3723 messages) and also data for retries of a specific message at this host.
3724 If either of these retry records are actually read, the keys used are
3725 returned to save recomputing them later. */
3726
3727 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3728 US"retry_include_ip_address", ob->retry_include_ip_address,
3729 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3730 continue; /* with next host */
3731
3732 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3733 incl_ip, &retry_host_key, &retry_message_key);
3734
3735 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3736 (host->address == NULL)? US"" : host->address, pistring,
3737 (host->status == hstatus_usable)? "usable" :
3738 (host->status == hstatus_unusable)? "unusable" :
3739 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3740
3741 /* Skip this address if not usable at this time, noting if it wasn't
3742 actually expired, both locally and in the address. */
3743
3744 switch (host->status)
3745 {
3746 case hstatus_unusable:
3747 expired = FALSE;
3748 setflag(addrlist, af_retry_skipped);
3749 /* Fall through */
3750
3751 case hstatus_unusable_expired:
3752 switch (host->why)
3753 {
3754 case hwhy_retry: hosts_retry++; break;
3755 case hwhy_failed: hosts_fail++; break;
3756 case hwhy_deferred: hosts_defer++; break;
3757 }
3758
3759 /* If there was a retry message key, implying that previously there
3760 was a message-specific defer, we don't want to update the list of
3761 messages waiting for these hosts. */
3762
3763 if (retry_message_key) update_waiting = FALSE;
3764 continue; /* With the next host or IP address */
3765 }
3766 }
3767
3768 /* Second time round the loop: if the address is set but expired, and
3769 the message is newer than the last try, let it through. */
3770
3771 else
3772 {
3773 if ( !host->address
3774 || host->status != hstatus_unusable_expired
3775 || host->last_try > received_time)
3776 continue;
3777 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
3778 host->name, host->address, pistring);
3779 host_is_expired = TRUE;
3780 }
3781
3782 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3783 it remains TRUE only if all hosts are expired and none are actually tried.
3784 */
3785
3786 expired = FALSE;
3787
3788 /* If this host is listed as one to which access must be serialized,
3789 see if another Exim process has a connection to it, and if so, skip
3790 this host. If not, update the database to record our connection to it
3791 and remember this for later deletion. Do not do any of this if we are
3792 sending the message down a pre-existing connection. */
3793
3794 if ( !continue_hostname
3795 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
3796 {
3797 serialize_key = string_sprintf("host-serialize-%s", host->name);
3798 if (!enq_start(serialize_key, 1))
3799 {
3800 DEBUG(D_transport)
3801 debug_printf("skipping host %s because another Exim process "
3802 "is connected to it\n", host->name);
3803 hosts_serial++;
3804 continue;
3805 }
3806 }
3807
3808 /* OK, we have an IP address that is not waiting for its retry time to
3809 arrive (it might be expired) OR (second time round the loop) we have an
3810 expired host that hasn't been tried since the message arrived. Have a go
3811 at delivering the message to it. First prepare the addresses by flushing
3812 out the result of previous attempts, and finding the first address that
3813 is still to be delivered. */
3814
3815 first_addr = prepare_addresses(addrlist, host);
3816
3817 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3818 message_id, host->name, host->address, addrlist->address,
3819 addrlist->next ? ", ..." : "");
3820
3821 set_process_info("delivering %s to %s [%s] (%s%s)",
3822 message_id, host->name, host->address, addrlist->address,
3823 addrlist->next ? ", ..." : "");
3824
3825 /* This is not for real; don't do the delivery. If there are
3826 any remaining hosts, list them. */
3827
3828 if (dont_deliver)
3829 {
3830 host_item *host2;
3831 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3832 for (addr = addrlist; addr; addr = addr->next)
3833 {
3834 addr->host_used = host;
3835 addr->special_action = '*';
3836 addr->message = US"delivery bypassed by -N option";
3837 }
3838 DEBUG(D_transport)
3839 {
3840 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3841 "*** host and remaining hosts:\n", tblock->name);
3842 for (host2 = host; host2; host2 = host2->next)
3843 debug_printf(" %s [%s]\n", host2->name,
3844 host2->address ? host2->address : US"unset");
3845 }
3846 rc = OK;
3847 }
3848
3849 /* This is for real. If the host is expired, we don't count it for
3850 hosts_max_retry. This ensures that all hosts must expire before an address
3851 is timed out, unless hosts_max_try_hardlimit (which protects against
3852 lunatic DNS configurations) is reached.
3853
3854 If the host is not expired and we are about to hit the hosts_max_retry
3855 limit, check to see if there is a subsequent hosts with a different MX
3856 value. If so, make that the next host, and don't count this one. This is a
3857 heuristic to make sure that different MXs do get tried. With a normal kind
3858 of retry rule, they would get tried anyway when the earlier hosts were
3859 delayed, but if the domain has a "retry every time" type of rule - as is
3860 often used for the the very large ISPs, that won't happen. */
3861
3862 else
3863 {
3864 host_item * thost;
3865 /* Make a copy of the host if it is local to this invocation
3866 of the transport. */
3867
3868 if (expanded_hosts)
3869 {
3870 thost = store_get(sizeof(host_item));
3871 *thost = *host;
3872 thost->name = string_copy(host->name);
3873 thost->address = string_copy(host->address);
3874 }
3875 else
3876 thost = host;
3877
3878 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3879 {
3880 host_item *h;
3881 DEBUG(D_transport)
3882 debug_printf("hosts_max_try limit reached with this host\n");
3883 for (h = host; h; h = h->next) if (h->mx != host->mx)
3884 {
3885 nexthost = h;
3886 unexpired_hosts_tried--;
3887 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3888 "and will be tried\n");
3889 break;
3890 }
3891 }
3892
3893 /* Attempt the delivery. */
3894
3895 total_hosts_tried++;
3896 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3897 &message_defer, FALSE);
3898
3899 /* Yield is one of:
3900 OK => connection made, each address contains its result;
3901 message_defer is set for message-specific defers (when all
3902 recipients are marked defer)
3903 DEFER => there was a non-message-specific delivery problem;
3904 ERROR => there was a problem setting up the arguments for a filter,
3905 or there was a problem with expanding added headers
3906 */
3907
3908 /* If the result is not OK, there was a non-message-specific problem.
3909 If the result is DEFER, we need to write to the logs saying what happened
3910 for this particular host, except in the case of authentication and TLS
3911 failures, where the log has already been written. If all hosts defer a
3912 general message is written at the end. */
3913
3914 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
3915 && first_addr->basic_errno != ERRNO_TLSFAILURE)
3916 write_logs(first_addr, host);
3917
3918 #ifndef DISABLE_EVENT
3919 if (rc == DEFER)
3920 deferred_event_raise(first_addr, host);
3921 #endif
3922
3923 /* If STARTTLS was accepted, but there was a failure in setting up the
3924 TLS session (usually a certificate screwup), and the host is not in
3925 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3926 TLS forcibly turned off. We have to start from scratch with a new SMTP
3927 connection. That's why the retry is done from here, not from within
3928 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3929 session, so the in-clear transmission after those errors, if permitted,
3930 happens inside smtp_deliver().] */
3931
3932 #ifdef SUPPORT_TLS
3933 if ( rc == DEFER
3934 && first_addr->basic_errno == ERRNO_TLSFAILURE
3935 && ob->tls_tempfail_tryclear
3936 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3937 )
3938 {
3939 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3940 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3941 first_addr = prepare_addresses(addrlist, host);
3942 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3943 &message_defer, TRUE);
3944 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3945 write_logs(first_addr, host);
3946 # ifndef DISABLE_EVENT
3947 if (rc == DEFER)
3948 deferred_event_raise(first_addr, host);
3949 # endif
3950 }
3951 #endif /*SUPPORT_TLS*/
3952 }
3953
3954 /* Delivery attempt finished */
3955
3956 rs = rc == OK ? US"OK"
3957 : rc == DEFER ? US"DEFER"
3958 : rc == ERROR ? US"ERROR"
3959 : US"?";
3960
3961 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3962 message_id, host->name, host->address, addrlist->address,
3963 addrlist->next ? " (& others)" : "", rs);
3964
3965 /* Release serialization if set up */
3966
3967 if (serialize_key) enq_end(serialize_key);
3968
3969 /* If the result is DEFER, or if a host retry record is known to exist, we
3970 need to add an item to the retry chain for updating the retry database
3971 at the end of delivery. We only need to add the item to the top address,
3972 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3973 for any other delivery attempts using the same address. (It is copied into
3974 the unusable tree at the outer level, so even if different address blocks
3975 contain the same address, it still won't get tried again.) */
3976
3977 if (rc == DEFER || retry_host_key)
3978 {
3979 int delete_flag = rc != DEFER ? rf_delete : 0;
3980 if (!retry_host_key)
3981 {
3982 BOOL incl_ip;
3983 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3984 US"retry_include_ip_address", ob->retry_include_ip_address,
3985 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3986 incl_ip = TRUE; /* error; use most-specific retry record */
3987
3988 retry_host_key = incl_ip
3989 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
3990 : string_sprintf("T:%S%s", host->name, pistring);
3991 }
3992
3993 /* If a delivery of another message over an existing SMTP connection
3994 yields DEFER, we do NOT set up retry data for the host. This covers the
3995 case when there are delays in routing the addresses in the second message
3996 that are so long that the server times out. This is alleviated by not
3997 routing addresses that previously had routing defers when handling an
3998 existing connection, but even so, this case may occur (e.g. if a
3999 previously happily routed address starts giving routing defers). If the
4000 host is genuinely down, another non-continued message delivery will
4001 notice it soon enough. */
4002
4003 if (delete_flag != 0 || !continue_hostname)
4004 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
4005
4006 /* We may have tried an expired host, if its retry time has come; ensure
4007 the status reflects the expiry for the benefit of any other addresses. */
4008
4009 if (rc == DEFER)
4010 {
4011 host->status = host_is_expired
4012 ? hstatus_unusable_expired : hstatus_unusable;
4013 host->why = hwhy_deferred;
4014 }
4015 }
4016
4017 /* If message_defer is set (host was OK, but every recipient got deferred
4018 because of some message-specific problem), or if that had happened
4019 previously so that a message retry key exists, add an appropriate item
4020 to the retry chain. Note that if there was a message defer but now there is
4021 a host defer, the message defer record gets deleted. That seems perfectly
4022 reasonable. Also, stop the message from being remembered as waiting
4023 for specific hosts. */
4024
4025 if (message_defer || retry_message_key)
4026 {
4027 int delete_flag = message_defer ? 0 : rf_delete;
4028 if (!retry_message_key)
4029 {
4030 BOOL incl_ip;
4031 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4032 US"retry_include_ip_address", ob->retry_include_ip_address,
4033 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4034 incl_ip = TRUE; /* error; use most-specific retry record */
4035
4036 retry_message_key = incl_ip
4037 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4038 message_id)
4039 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4040 }
4041 retry_add_item(addrlist, retry_message_key,
4042 rf_message | rf_host | delete_flag);
4043 update_waiting = FALSE;
4044 }
4045
4046 /* Any return other than DEFER (that is, OK or ERROR) means that the
4047 addresses have got their final statuses filled in for this host. In the OK
4048 case, see if any of them are deferred. */
4049
4050 if (rc == OK)
4051 for (addr = addrlist; addr; addr = addr->next)
4052 if (addr->transport_return == DEFER)
4053 {
4054 some_deferred = TRUE;
4055 break;
4056 }
4057
4058 /* If no addresses deferred or the result was ERROR, return. We do this for
4059 ERROR because a failing filter set-up or add_headers expansion is likely to
4060 fail for any host we try. */
4061
4062 if (rc == ERROR || (rc == OK && !some_deferred))
4063 {
4064 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4065 return TRUE; /* Each address has its status */
4066 }
4067
4068 /* If the result was DEFER or some individual addresses deferred, let
4069 the loop run to try other hosts with the deferred addresses, except for the
4070 case when we were trying to deliver down an existing channel and failed.
4071 Don't try any other hosts in this case. */
4072
4073 if (continue_hostname) break;
4074
4075 /* If the whole delivery, or some individual addresses, were deferred and
4076 there are more hosts that could be tried, do not count this host towards
4077 the hosts_max_try limit if the age of the message is greater than the
4078 maximum retry time for this host. This means we may try try all hosts,
4079 ignoring the limit, when messages have been around for some time. This is
4080 important because if we don't try all hosts, the address will never time
4081 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4082
4083 if ((rc == DEFER || some_deferred) && nexthost)
4084 {
4085 BOOL timedout;
4086 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4087
4088 if (retry && retry->rules)
4089 {
4090 retry_rule *last_rule;
4091 for (last_rule = retry->rules;
4092 last_rule->next;
4093 last_rule = last_rule->next);
4094 timedout = time(NULL) - received_time > last_rule->timeout;
4095 }
4096 else timedout = TRUE; /* No rule => timed out */
4097
4098 if (timedout)
4099 {
4100 unexpired_hosts_tried--;
4101 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4102 "hosts_max_try (message older than host's retry time)\n");
4103 }
4104 }
4105 } /* End of loop for trying multiple hosts. */
4106
4107 /* This is the end of the loop that repeats iff expired is TRUE and
4108 ob->delay_after_cutoff is FALSE. The second time round we will
4109 try those hosts that haven't been tried since the message arrived. */
4110
4111 DEBUG(D_transport)
4112 {
4113 debug_printf("all IP addresses skipped or deferred at least one address\n");
4114 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4115 debug_printf("retrying IP addresses not tried since message arrived\n");
4116 }
4117 }
4118
4119
4120 /* Get here if all IP addresses are skipped or defer at least one address. In
4121 MUA wrapper mode, this will happen only for connection or other non-message-
4122 specific failures. Force the delivery status for all addresses to FAIL. */
4123
4124 if (mua_wrapper)
4125 {
4126 for (addr = addrlist; addr; addr = addr->next)
4127 addr->transport_return = FAIL;
4128 goto END_TRANSPORT;
4129 }
4130
4131 /* In the normal, non-wrapper case, add a standard message to each deferred
4132 address if there hasn't been an error, that is, if it hasn't actually been
4133 tried this time. The variable "expired" will be FALSE if any deliveries were
4134 actually tried, or if there was at least one host that was not expired. That
4135 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4136 a delivery has been tried, an error code will be set, and the failing of the
4137 message is handled by the retry code later.
4138
4139 If queue_smtp is set, or this transport was called to send a subsequent message
4140 down an existing TCP/IP connection, and something caused the host not to be
4141 found, we end up here, but can detect these cases and handle them specially. */
4142
4143 for (addr = addrlist; addr; addr = addr->next)
4144 {
4145 /* If host is not NULL, it means that we stopped processing the host list
4146 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4147 means we need to behave as if some hosts were skipped because their retry
4148 time had not come. Specifically, this prevents the address from timing out.
4149 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4150 hosts were tried. */
4151
4152 if (host)
4153 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4154 {
4155 DEBUG(D_transport)
4156 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4157 "hosts were tried\n");
4158 }
4159 else
4160 {
4161 DEBUG(D_transport)
4162 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4163 setflag(addr, af_retry_skipped);
4164 }
4165
4166 if (queue_smtp) /* no deliveries attempted */
4167 {
4168 addr->transport_return = DEFER;
4169 addr->basic_errno = 0;
4170 addr->message = US"SMTP delivery explicitly queued";
4171 }
4172
4173 else if ( addr->transport_return == DEFER
4174 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4175 && !addr->message
4176 )
4177 {
4178 addr->basic_errno = ERRNO_HRETRY;
4179 if (continue_hostname)
4180 addr->message = US"no host found for existing SMTP connection";
4181 else if (expired)
4182 {
4183 setflag(addr, af_pass_message); /* This is not a security risk */
4184 addr->message = string_sprintf(
4185 "all hosts%s have been failing for a long time %s",
4186 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4187 ob->delay_after_cutoff
4188 ? US"(and retry time not reached)"
4189 : US"and were last tried after this message arrived");
4190
4191 /* If we are already using fallback hosts, or there are no fallback hosts
4192 defined, convert the result to FAIL to cause a bounce. */
4193
4194 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4195 addr->transport_return = FAIL;
4196 }
4197 else
4198 {
4199 const char * s;
4200 if (hosts_retry == hosts_total)
4201 s = "retry time not reached for any host%s";
4202 else if (hosts_fail == hosts_total)
4203 s = "all host address lookups%s failed permanently";
4204 else if (hosts_defer == hosts_total)
4205 s = "all host address lookups%s failed temporarily";
4206 else if (hosts_serial == hosts_total)
4207 s = "connection limit reached for all hosts%s";
4208 else if (hosts_fail+hosts_defer == hosts_total)
4209 s = "all host address lookups%s failed";
4210 else
4211 s = "some host address lookups failed and retry time "
4212 "not reached for other hosts or connection limit reached%s";
4213
4214 addr->message = string_sprintf(s,
4215 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4216 }
4217 }
4218 }
4219
4220 /* Update the database which keeps information about which messages are waiting
4221 for which hosts to become available. For some message-specific errors, the
4222 update_waiting flag is turned off because we don't want follow-on deliveries in
4223 those cases. If this transport instance is explicitly limited to one message
4224 per connection then follow-on deliveries are not possible and there's no need
4225 to create/update the per-transport wait-<transport_name> database. */
4226
4227 if (update_waiting && tblock->connection_max_messages != 1)
4228 transport_update_waiting(hostlist, tblock->name);
4229
4230 END_TRANSPORT:
4231
4232 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4233
4234 return TRUE; /* Each address has its status */
4235 }
4236
4237 /* vi: aw ai sw=2
4238 */
4239 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.