projects / exim.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Support REQUIRETLS
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11
12 /* Options specific to the smtp transport. This transport also supports LMTP
13 over TCP/IP. The options must be in alphabetic order (note that "_" comes
14 before the lower case letters). Some live in the transport_instance block so as
15 to be publicly visible; these are flagged with opt_public. */
16
17 optionlist smtp_transport_options[] = {
18 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
19 (void *)offsetof(transport_instance, expand_multi_domain) },
20 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
21 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
22
23 { "address_retry_include_sender", opt_bool,
24 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
25 { "allow_localhost", opt_bool,
26 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
27 #ifdef EXPERIMENTAL_ARC
28 { "arc_sign", opt_stringptr,
29 (void *)offsetof(smtp_transport_options_block, arc_sign) },
30 #endif
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 # ifdef SUPPORT_DANE
42 { "dane_require_tls_ciphers", opt_stringptr,
43 (void *)offsetof(smtp_transport_options_block, dane_require_tls_ciphers) },
44 # endif
45 { "data_timeout", opt_time,
46 (void *)offsetof(smtp_transport_options_block, data_timeout) },
47 { "delay_after_cutoff", opt_bool,
48 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
49 #ifndef DISABLE_DKIM
50 { "dkim_canon", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
52 { "dkim_domain", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
54 { "dkim_hash", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_hash) },
56 { "dkim_identity", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_identity) },
58 { "dkim_private_key", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
60 { "dkim_selector", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
62 { "dkim_sign_headers", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
64 { "dkim_strict", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
66 { "dkim_timestamps", opt_stringptr,
67 (void *)offsetof(smtp_transport_options_block, dkim.dkim_timestamps) },
68 #endif
69 { "dns_qualify_single", opt_bool,
70 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
71 { "dns_search_parents", opt_bool,
72 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
73 { "dnssec_request_domains", opt_stringptr,
74 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
75 { "dnssec_require_domains", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
77 { "dscp", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, dscp) },
79 { "fallback_hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
81 { "final_timeout", opt_time,
82 (void *)offsetof(smtp_transport_options_block, final_timeout) },
83 { "gethostbyname", opt_bool,
84 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
85 { "helo_data", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, helo_data) },
87 { "hosts", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts) },
89 { "hosts_avoid_esmtp", opt_stringptr,
90 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
91 { "hosts_avoid_pipelining", opt_stringptr,
92 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
93 #ifdef SUPPORT_TLS
94 { "hosts_avoid_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
96 #endif
97 { "hosts_max_try", opt_int,
98 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
99 { "hosts_max_try_hardlimit", opt_int,
100 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
101 #ifdef SUPPORT_TLS
102 { "hosts_nopass_tls", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
104 { "hosts_noproxy_tls", opt_stringptr,
105 (void *)offsetof(smtp_transport_options_block, hosts_noproxy_tls) },
106 #endif
107 { "hosts_override", opt_bool,
108 (void *)offsetof(smtp_transport_options_block, hosts_override) },
109 { "hosts_randomize", opt_bool,
110 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
111 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
112 { "hosts_request_ocsp", opt_stringptr,
113 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
114 #endif
115 { "hosts_require_auth", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
117 #ifdef SUPPORT_TLS
118 # ifdef SUPPORT_DANE
119 { "hosts_require_dane", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
121 # endif
122 # ifndef DISABLE_OCSP
123 { "hosts_require_ocsp", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
125 # endif
126 { "hosts_require_tls", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
128 #endif
129 { "hosts_try_auth", opt_stringptr,
130 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
131 { "hosts_try_chunking", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
133 #if defined(SUPPORT_TLS) && defined(SUPPORT_DANE)
134 { "hosts_try_dane", opt_stringptr,
135 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
136 #endif
137 { "hosts_try_fastopen", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
139 #ifndef DISABLE_PRDR
140 { "hosts_try_prdr", opt_stringptr,
141 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
142 #endif
143 #ifdef SUPPORT_TLS
144 { "hosts_verify_avoid_tls", opt_stringptr,
145 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
146 #endif
147 { "interface", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, interface) },
149 { "keepalive", opt_bool,
150 (void *)offsetof(smtp_transport_options_block, keepalive) },
151 { "lmtp_ignore_quota", opt_bool,
152 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
153 { "max_rcpt", opt_int | opt_public,
154 (void *)offsetof(transport_instance, max_addresses) },
155 { "multi_domain", opt_expand_bool | opt_public,
156 (void *)offsetof(transport_instance, multi_domain) },
157 { "port", opt_stringptr,
158 (void *)offsetof(smtp_transport_options_block, port) },
159 { "protocol", opt_stringptr,
160 (void *)offsetof(smtp_transport_options_block, protocol) },
161 { "retry_include_ip_address", opt_expand_bool,
162 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
163 { "serialize_hosts", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
165 { "size_addition", opt_int,
166 (void *)offsetof(smtp_transport_options_block, size_addition) }
167 #ifdef SUPPORT_SOCKS
168 ,{ "socks_proxy", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
170 #endif
171 #ifdef SUPPORT_TLS
172 ,{ "tls_certificate", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
174 { "tls_crl", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block, tls_crl) },
176 { "tls_dh_min_bits", opt_int,
177 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
178 { "tls_privatekey", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
180 { "tls_require_ciphers", opt_stringptr,
181 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
182 { "tls_sni", opt_stringptr,
183 (void *)offsetof(smtp_transport_options_block, tls_sni) },
184 { "tls_tempfail_tryclear", opt_bool,
185 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
186 { "tls_try_verify_hosts", opt_stringptr,
187 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
188 { "tls_verify_cert_hostnames", opt_stringptr,
189 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
190 { "tls_verify_certificates", opt_stringptr,
191 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
192 { "tls_verify_hosts", opt_stringptr,
193 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
194 #endif
195 };
196
197 /* Size of the options list. An extern variable has to be used so that its
198 address can appear in the tables drtables.c. */
199
200 int smtp_transport_options_count =
201 sizeof(smtp_transport_options)/sizeof(optionlist);
202
203
204 #ifdef MACRO_PREDEF
205
206 /* Dummy values */
207 smtp_transport_options_block smtp_transport_option_defaults = {0};
208 void smtp_transport_init(transport_instance *tblock) {}
209 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
210 void smtp_transport_closedown(transport_instance *tblock) {}
211
212 #else /*!MACRO_PREDEF*/
213
214
215 /* Default private options block for the smtp transport. */
216
217 smtp_transport_options_block smtp_transport_option_defaults = {
218 .hosts = NULL,
219 .fallback_hosts = NULL,
220 .hostlist = NULL,
221 .fallback_hostlist = NULL,
222 .helo_data = US"$primary_hostname",
223 .interface = NULL,
224 .port = NULL,
225 .protocol = US"smtp",
226 .dscp = NULL,
227 .serialize_hosts = NULL,
228 .hosts_try_auth = NULL,
229 .hosts_require_auth = NULL,
230 .hosts_try_chunking = US"*",
231 #ifdef SUPPORT_DANE
232 .hosts_try_dane = NULL,
233 .hosts_require_dane = NULL,
234 .dane_require_tls_ciphers = NULL,
235 #endif
236 .hosts_try_fastopen = NULL,
237 #ifndef DISABLE_PRDR
238 .hosts_try_prdr = US"*",
239 #endif
240 #ifndef DISABLE_OCSP
241 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
242 .hosts_require_ocsp = NULL,
243 #endif
244 .hosts_require_tls = NULL,
245 .hosts_avoid_tls = NULL,
246 .hosts_verify_avoid_tls = NULL,
247 .hosts_avoid_pipelining = NULL,
248 .hosts_avoid_esmtp = NULL,
249 #ifdef SUPPORT_TLS
250 .hosts_nopass_tls = NULL,
251 .hosts_noproxy_tls = US"*",
252 #endif
253 .command_timeout = 5*60,
254 .connect_timeout = 5*60,
255 .data_timeout = 5*60,
256 .final_timeout = 10*60,
257 .size_addition = 1024,
258 .hosts_max_try = 5,
259 .hosts_max_try_hardlimit = 50,
260 .address_retry_include_sender = TRUE,
261 .allow_localhost = FALSE,
262 .authenticated_sender_force = FALSE,
263 .gethostbyname = FALSE,
264 .dns_qualify_single = TRUE,
265 .dns_search_parents = FALSE,
266 .dnssec = { .request=NULL, .require=NULL },
267 .delay_after_cutoff = TRUE,
268 .hosts_override = FALSE,
269 .hosts_randomize = FALSE,
270 .keepalive = TRUE,
271 .lmtp_ignore_quota = FALSE,
272 .expand_retry_include_ip_address = NULL,
273 .retry_include_ip_address = TRUE,
274 #ifdef SUPPORT_SOCKS
275 .socks_proxy = NULL,
276 #endif
277 #ifdef SUPPORT_TLS
278 .tls_certificate = NULL,
279 .tls_crl = NULL,
280 .tls_privatekey = NULL,
281 .tls_require_ciphers = NULL,
282 .tls_sni = NULL,
283 .tls_verify_certificates = US"system",
284 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
285 .tls_tempfail_tryclear = TRUE,
286 .tls_verify_hosts = NULL,
287 .tls_try_verify_hosts = US"*",
288 .tls_verify_cert_hostnames = US"*",
289 #endif
290 #ifndef DISABLE_DKIM
291 .dkim =
292 {.dkim_domain = NULL,
293 .dkim_identity = NULL,
294 .dkim_private_key = NULL,
295 .dkim_selector = NULL,
296 .dkim_canon = NULL,
297 .dkim_sign_headers = NULL,
298 .dkim_strict = NULL,
299 .dkim_hash = US"sha256",
300 .dkim_timestamps = NULL,
301 .dot_stuffed = FALSE,
302 .force_bodyhash = FALSE,
303 # ifdef EXPERIMENTAL_ARC
304 .arc_signspec = NULL,
305 # endif
306 },
307 # ifdef EXPERIMENTAL_ARC
308 .arc_sign = NULL,
309 # endif
310 #endif
311 };
312
313 /* some DSN flags for use later */
314
315 static int rf_list[] = {rf_notify_never, rf_notify_success,
316 rf_notify_failure, rf_notify_delay };
317
318 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
319
320
321
322 /* Local statics */
323
324 static uschar *smtp_command; /* Points to last cmd for error messages */
325 static uschar *mail_command; /* Points to MAIL cmd for error messages */
326 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
327 static BOOL update_waiting; /* TRUE to update the "wait" database */
328
329 /*XXX move to smtp_context */
330 static BOOL pipelining_active; /* current transaction is in pipe mode */
331
332
333 /*************************************************
334 * Setup entry point *
335 *************************************************/
336
337 /* This function is called when the transport is about to be used,
338 but before running it in a sub-process. It is used for two things:
339
340 (1) To set the fallback host list in addresses, when delivering.
341 (2) To pass back the interface, port, protocol, and other options, for use
342 during callout verification.
343
344 Arguments:
345 tblock pointer to the transport instance block
346 addrlist list of addresses about to be transported
347 tf if not NULL, pointer to block in which to return options
348 uid the uid that will be set (not used)
349 gid the gid that will be set (not used)
350 errmsg place for error message (not used)
351
352 Returns: OK always (FAIL, DEFER not used)
353 */
354
355 static int
356 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
357 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
358 {
359 smtp_transport_options_block *ob =
360 (smtp_transport_options_block *)(tblock->options_block);
361
362 errmsg = errmsg; /* Keep picky compilers happy */
363 uid = uid;
364 gid = gid;
365
366 /* Pass back options if required. This interface is getting very messy. */
367
368 if (tf)
369 {
370 tf->interface = ob->interface;
371 tf->port = ob->port;
372 tf->protocol = ob->protocol;
373 tf->hosts = ob->hosts;
374 tf->hosts_override = ob->hosts_override;
375 tf->hosts_randomize = ob->hosts_randomize;
376 tf->gethostbyname = ob->gethostbyname;
377 tf->qualify_single = ob->dns_qualify_single;
378 tf->search_parents = ob->dns_search_parents;
379 tf->helo_data = ob->helo_data;
380 }
381
382 /* Set the fallback host list for all the addresses that don't have fallback
383 host lists, provided that the local host wasn't present in the original host
384 list. */
385
386 if (!testflag(addrlist, af_local_host_removed))
387 for (; addrlist; addrlist = addrlist->next)
388 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
389
390 return OK;
391 }
392
393
394
395 /*************************************************
396 * Initialization entry point *
397 *************************************************/
398
399 /* Called for each instance, after its options have been read, to
400 enable consistency checks to be done, or anything else that needs
401 to be set up.
402
403 Argument: pointer to the transport instance block
404 Returns: nothing
405 */
406
407 void
408 smtp_transport_init(transport_instance *tblock)
409 {
410 smtp_transport_options_block *ob =
411 (smtp_transport_options_block *)(tblock->options_block);
412
413 /* Retry_use_local_part defaults FALSE if unset */
414
415 if (tblock->retry_use_local_part == TRUE_UNSET)
416 tblock->retry_use_local_part = FALSE;
417
418 /* Set the default port according to the protocol */
419
420 if (ob->port == NULL)
421 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
422 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
423
424 /* Set up the setup entry point, to be called before subprocesses for this
425 transport. */
426
427 tblock->setup = smtp_transport_setup;
428
429 /* Complain if any of the timeouts are zero. */
430
431 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
432 ob->final_timeout <= 0)
433 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
434 "command, data, or final timeout value is zero for %s transport",
435 tblock->name);
436
437 /* If hosts_override is set and there are local hosts, set the global
438 flag that stops verify from showing router hosts. */
439
440 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
441
442 /* If there are any fallback hosts listed, build a chain of host items
443 for them, but do not do any lookups at this time. */
444
445 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
446 }
447
448
449
450
451
452 /*************************************************
453 * Set delivery info into all active addresses *
454 *************************************************/
455
456 /* Only addresses whose status is >= PENDING are relevant. A lesser
457 status means that an address is not currently being processed.
458
459 Arguments:
460 addrlist points to a chain of addresses
461 errno_value to put in each address's errno field
462 msg to put in each address's message field
463 rc to put in each address's transport_return field
464 pass_message if TRUE, set the "pass message" flag in the address
465 host if set, mark addrs as having used this host
466 smtp_greeting from peer
467 helo_response from peer
468
469 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
470 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
471 this particular type of timeout.
472
473 Returns: nothing
474 */
475
476 static void
477 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
478 BOOL pass_message, host_item * host
479 #ifdef EXPERIMENTAL_DSN_INFO
480 , const uschar * smtp_greeting, const uschar * helo_response
481 #endif
482 )
483 {
484 address_item *addr;
485 int orvalue = 0;
486 if (errno_value == ERRNO_CONNECTTIMEOUT)
487 {
488 errno_value = ETIMEDOUT;
489 orvalue = RTEF_CTOUT;
490 }
491 for (addr = addrlist; addr; addr = addr->next)
492 if (addr->transport_return >= PENDING)
493 {
494 addr->basic_errno = errno_value;
495 addr->more_errno |= orvalue;
496 if (msg)
497 {
498 addr->message = msg;
499 if (pass_message) setflag(addr, af_pass_message);
500 }
501 addr->transport_return = rc;
502 if (host)
503 {
504 addr->host_used = host;
505 #ifdef EXPERIMENTAL_DSN_INFO
506 if (smtp_greeting)
507 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
508 addr->smtp_greeting = smtp_greeting;
509
510 if (helo_response)
511 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
512 addr->helo_response = helo_response;
513 #endif
514 }
515 }
516 }
517
518 static void
519 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
520 BOOL pass_message)
521 {
522 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
523 #ifdef EXPERIMENTAL_DSN_INFO
524 , NULL, NULL
525 #endif
526 );
527 }
528
529
530 /*************************************************
531 * Check an SMTP response *
532 *************************************************/
533
534 /* This function is given an errno code and the SMTP response buffer
535 to analyse, together with the host identification for generating messages. It
536 sets an appropriate message and puts the first digit of the response code into
537 the yield variable. If no response was actually read, a suitable digit is
538 chosen.
539
540 Arguments:
541 host the current host, to get its name for messages
542 errno_value pointer to the errno value
543 more_errno from the top address for use with ERRNO_FILTER_FAIL
544 buffer the SMTP response buffer
545 yield where to put a one-digit SMTP response code
546 message where to put an error message
547 pass_message set TRUE if message is an SMTP response
548
549 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
550 */
551
552 static BOOL
553 check_response(host_item *host, int *errno_value, int more_errno,
554 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
555 {
556 uschar * pl = pipelining_active ? US"pipelined " : US"";
557 const uschar * s;
558
559 *yield = '4'; /* Default setting is to give a temporary error */
560
561 switch(*errno_value)
562 {
563 case ETIMEDOUT: /* Handle response timeout */
564 *message = US string_sprintf("SMTP timeout after %s%s",
565 pl, smtp_command);
566 if (transport_count > 0)
567 *message = US string_sprintf("%s (%d bytes written)", *message,
568 transport_count);
569 return FALSE;
570
571 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
572 s = string_printing(buffer);
573 while (isspace(*s)) s++;
574 *message = *s == 0
575 ? string_sprintf("Malformed SMTP reply (an empty line) "
576 "in response to %s%s", pl, smtp_command)
577 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
578 pl, smtp_command, s);
579 return FALSE;
580
581 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
582 can't send QUIT as we mustn't end the DATA. */
583 *message = string_sprintf("transport filter process failed (%d)%s",
584 more_errno,
585 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
586 return FALSE;
587
588 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
589 can't send QUIT as we mustn't end the DATA. */
590 *message =
591 string_sprintf("failed to expand headers_add or headers_remove: %s",
592 expand_string_message);
593 return FALSE;
594
595 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
596 *message = string_sprintf("failed to write a data block");
597 return FALSE;
598
599 #ifdef SUPPORT_I18N
600 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
601 *message = US"utf8 support required but not offered for forwarding";
602 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
603 return TRUE;
604 #endif
605 }
606
607 /* Handle error responses from the remote mailer. */
608
609 if (buffer[0] != 0)
610 {
611 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
612 "%s", pl, smtp_command, s = string_printing(buffer));
613 *pass_message = TRUE;
614 *yield = buffer[0];
615 return TRUE;
616 }
617
618 /* No data was read. If there is no errno, this must be the EOF (i.e.
619 connection closed) case, which causes deferral. An explicit connection reset
620 error has the same effect. Otherwise, put the host's identity in the message,
621 leaving the errno value to be interpreted as well. In all cases, we have to
622 assume the connection is now dead. */
623
624 if (*errno_value == 0 || *errno_value == ECONNRESET)
625 {
626 *errno_value = ERRNO_SMTPCLOSED;
627 *message = US string_sprintf("Remote host closed connection "
628 "in response to %s%s", pl, smtp_command);
629 }
630 else
631 *message = US string_sprintf("%s [%s]", host->name, host->address);
632
633 return FALSE;
634 }
635
636
637
638 /*************************************************
639 * Write error message to logs *
640 *************************************************/
641
642 /* This writes to the main log and to the message log.
643
644 Arguments:
645 host the current host
646 detail the current message (addr_item->message)
647 basic_errno the errno (addr_item->basic_errno)
648
649 Returns: nothing
650 */
651
652 static void
653 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
654 {
655
656
657 uschar *message = LOGGING(outgoing_port)
658 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
659 host->port == PORT_NONE ? 25 : host->port)
660 : string_sprintf("H=%s [%s]", host->name, host->address);
661
662 if (suffix)
663 {
664 message = string_sprintf("%s: %s", message, suffix);
665 if (basic_errno > 0)
666 message = string_sprintf("%s: %s", message, strerror(basic_errno));
667 }
668 else
669 message = string_sprintf("%s %s", message, exim_errstr(basic_errno));
670
671 log_write(0, LOG_MAIN, "%s", message);
672 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
673 }
674
675 static void
676 msglog_line(host_item * host, uschar * message)
677 {
678 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
679 host->name, host->address, message);
680 }
681
682
683
684 #ifndef DISABLE_EVENT
685 /*************************************************
686 * Post-defer action *
687 *************************************************/
688
689 /* This expands an arbitrary per-transport string.
690 It might, for example, be used to write to the database log.
691
692 Arguments:
693 addr the address item containing error information
694 host the current host
695
696 Returns: nothing
697 */
698
699 static void
700 deferred_event_raise(address_item *addr, host_item *host)
701 {
702 uschar * action = addr->transport->event_action;
703 const uschar * save_domain;
704 uschar * save_local;
705
706 if (!action)
707 return;
708
709 save_domain = deliver_domain;
710 save_local = deliver_localpart;
711
712 /*XXX would ip & port already be set up? */
713 deliver_host_address = string_copy(host->address);
714 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
715 event_defer_errno = addr->basic_errno;
716
717 router_name = addr->router->name;
718 transport_name = addr->transport->name;
719 deliver_domain = addr->domain;
720 deliver_localpart = addr->local_part;
721
722 (void) event_raise(action, US"msg:host:defer",
723 addr->message
724 ? addr->basic_errno > 0
725 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
726 : string_copy(addr->message)
727 : addr->basic_errno > 0
728 ? string_copy(US strerror(addr->basic_errno))
729 : NULL);
730
731 deliver_localpart = save_local;
732 deliver_domain = save_domain;
733 router_name = transport_name = NULL;
734 }
735 #endif
736
737 /*************************************************
738 * Synchronize SMTP responses *
739 *************************************************/
740
741 /* This function is called from smtp_deliver() to receive SMTP responses from
742 the server, and match them up with the commands to which they relate. When
743 PIPELINING is not in use, this function is called after every command, and is
744 therefore somewhat over-engineered, but it is simpler to use a single scheme
745 that works both with and without PIPELINING instead of having two separate sets
746 of code.
747
748 The set of commands that are buffered up with pipelining may start with MAIL
749 and may end with DATA; in between are RCPT commands that correspond to the
750 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
751 etc.) are never buffered.
752
753 Errors after MAIL or DATA abort the whole process leaving the response in the
754 buffer. After MAIL, pending responses are flushed, and the original command is
755 re-instated in big_buffer for error messages. For RCPT commands, the remote is
756 permitted to reject some recipient addresses while accepting others. However
757 certain errors clearly abort the whole process. Set the value in
758 transport_return to PENDING_OK if the address is accepted. If there is a
759 subsequent general error, it will get reset accordingly. If not, it will get
760 converted to OK at the end.
761
762 Arguments:
763 sx smtp connection context
764 count the number of responses to read
765 pending_DATA 0 if last command sent was not DATA
766 +1 if previously had a good recipient
767 -1 if not previously had a good recipient
768
769 Returns: 3 if at least one address had 2xx and one had 5xx
770 2 if at least one address had 5xx but none had 2xx
771 1 if at least one host had a 2xx response, but none had 5xx
772 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
773 -1 timeout while reading RCPT response
774 -2 I/O or other non-response error for RCPT
775 -3 DATA or MAIL failed - errno and buffer set
776 */
777
778 static int
779 sync_responses(smtp_context * sx, int count, int pending_DATA)
780 {
781 address_item *addr = sx->sync_addr;
782 smtp_transport_options_block *ob =
783 (smtp_transport_options_block *)sx->tblock->options_block;
784 int yield = 0;
785
786 /* Handle the response for a MAIL command. On error, reinstate the original
787 command in big_buffer for error message use, and flush any further pending
788 responses before returning, except after I/O errors and timeouts. */
789
790 if (sx->pending_MAIL)
791 {
792 count--;
793 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
794 '2', ob->command_timeout))
795 {
796 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
797 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
798 if (errno == 0 && sx->buffer[0] != 0)
799 {
800 uschar flushbuffer[4096];
801 int save_errno = 0;
802 if (sx->buffer[0] == '4')
803 {
804 save_errno = ERRNO_MAIL4XX;
805 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
806 }
807 while (count-- > 0)
808 {
809 if (!smtp_read_response(&sx->inblock, flushbuffer, sizeof(flushbuffer),
810 '2', ob->command_timeout)
811 && (errno != 0 || flushbuffer[0] == 0))
812 break;
813 }
814 errno = save_errno;
815 }
816
817 if (pending_DATA) count--; /* Number of RCPT responses to come */
818 while (count-- > 0) /* Mark any pending addrs with the host used */
819 {
820 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
821 addr->host_used = sx->host;
822 addr = addr->next;
823 }
824 return -3;
825 }
826 }
827
828 if (pending_DATA) count--; /* Number of RCPT responses to come */
829
830 /* Read and handle the required number of RCPT responses, matching each one up
831 with an address by scanning for the next address whose status is PENDING_DEFER.
832 */
833
834 while (count-- > 0)
835 {
836 while (addr->transport_return != PENDING_DEFER)
837 if (!(addr = addr->next))
838 return -2;
839
840 /* The address was accepted */
841 addr->host_used = sx->host;
842
843 if (smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
844 '2', ob->command_timeout))
845 {
846 yield |= 1;
847 addr->transport_return = PENDING_OK;
848
849 /* If af_dr_retry_exists is set, there was a routing delay on this address;
850 ensure that any address-specific retry record is expunged. We do this both
851 for the basic key and for the version that also includes the sender. */
852
853 if (testflag(addr, af_dr_retry_exists))
854 {
855 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
856 sender_address);
857 retry_add_item(addr, altkey, rf_delete);
858 retry_add_item(addr, addr->address_retry_key, rf_delete);
859 }
860 }
861
862 /* Timeout while reading the response */
863
864 else if (errno == ETIMEDOUT)
865 {
866 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
867 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
868 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
869 retry_add_item(addr, addr->address_retry_key, 0);
870 update_waiting = FALSE;
871 return -1;
872 }
873
874 /* Handle other errors in obtaining an SMTP response by returning -1. This
875 will cause all the addresses to be deferred. Restore the SMTP command in
876 big_buffer for which we are checking the response, so the error message
877 makes sense. */
878
879 else if (errno != 0 || sx->buffer[0] == 0)
880 {
881 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
882 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
883 return -2;
884 }
885
886 /* Handle SMTP permanent and temporary response codes. */
887
888 else
889 {
890 addr->message =
891 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
892 "%s", transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes),
893 string_printing(sx->buffer));
894 setflag(addr, af_pass_message);
895 if (!sx->verify)
896 msglog_line(sx->host, addr->message);
897
898 /* The response was 5xx */
899
900 if (sx->buffer[0] == '5')
901 {
902 addr->transport_return = FAIL;
903 yield |= 2;
904 }
905
906 /* The response was 4xx */
907
908 else
909 {
910 addr->transport_return = DEFER;
911 addr->basic_errno = ERRNO_RCPT4XX;
912 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
913
914 if (!sx->verify)
915 {
916 #ifndef DISABLE_EVENT
917 event_defer_errno = addr->more_errno;
918 msg_event_raise(US"msg:rcpt:host:defer", addr);
919 #endif
920
921 /* Log temporary errors if there are more hosts to be tried.
922 If not, log this last one in the == line. */
923
924 if (sx->host->next)
925 log_write(0, LOG_MAIN, "H=%s [%s]: %s",
926 sx->host->name, sx->host->address, addr->message);
927
928 #ifndef DISABLE_EVENT
929 else
930 msg_event_raise(US"msg:rcpt:defer", addr);
931 #endif
932
933 /* Do not put this message on the list of those waiting for specific
934 hosts, as otherwise it is likely to be tried too often. */
935
936 update_waiting = FALSE;
937
938 /* Add a retry item for the address so that it doesn't get tried again
939 too soon. If address_retry_include_sender is true, add the sender address
940 to the retry key. */
941
942 retry_add_item(addr,
943 ob->address_retry_include_sender
944 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
945 : addr->address_retry_key,
946 0);
947 }
948 }
949 }
950 } /* Loop for next RCPT response */
951
952 /* Update where to start at for the next block of responses, unless we
953 have already handled all the addresses. */
954
955 if (addr) sx->sync_addr = addr->next;
956
957 /* Handle a response to DATA. If we have not had any good recipients, either
958 previously or in this block, the response is ignored. */
959
960 if (pending_DATA != 0 &&
961 !smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
962 '3', ob->command_timeout))
963 {
964 int code;
965 uschar *msg;
966 BOOL pass_message;
967 if (pending_DATA > 0 || (yield & 1) != 0)
968 {
969 if (errno == 0 && sx->buffer[0] == '4')
970 {
971 errno = ERRNO_DATA4XX;
972 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
973 }
974 return -3;
975 }
976 (void)check_response(sx->host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
977 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
978 "is in use and there were no good recipients\n", msg);
979 }
980
981 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
982 present) received 3xx. If any RCPTs were handled and yielded anything other
983 than 4xx, yield will be set non-zero. */
984
985 return yield;
986 }
987
988
989
990 /* Do the client side of smtp-level authentication */
991 /*
992 Arguments:
993 buffer EHLO response from server (gets overwritten)
994 addrlist chain of potential addresses to deliver
995 host host to deliver to
996 ob transport options
997 ibp, obp comms channel control blocks
998
999 Returns:
1000 OK Success, or failed (but not required): global "smtp_authenticated" set
1001 DEFER Failed authentication (and was required)
1002 ERROR Internal problem
1003
1004 FAIL_SEND Failed communications - transmit
1005 FAIL - response
1006 */
1007
1008 int
1009 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
1010 smtp_transport_options_block *ob, BOOL is_esmtp,
1011 smtp_inblock *ibp, smtp_outblock *obp)
1012 {
1013 int require_auth;
1014 uschar *fail_reason = US"server did not advertise AUTH support";
1015
1016 smtp_authenticated = FALSE;
1017 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1018 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1019
1020 if (is_esmtp && !regex_AUTH) regex_AUTH =
1021 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1022 FALSE, TRUE);
1023
1024 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1025 {
1026 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1027 expand_nmax = -1; /* reset */
1028
1029 /* Must not do this check until after we have saved the result of the
1030 regex match above. */
1031
1032 if (require_auth == OK ||
1033 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1034 {
1035 auth_instance *au;
1036 fail_reason = US"no common mechanisms were found";
1037
1038 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1039
1040 /* Scan the configured authenticators looking for one which is configured
1041 for use as a client, which is not suppressed by client_condition, and
1042 whose name matches an authentication mechanism supported by the server.
1043 If one is found, attempt to authenticate by calling its client function.
1044 */
1045
1046 for (au = auths; !smtp_authenticated && au; au = au->next)
1047 {
1048 uschar *p = names;
1049 if (!au->client ||
1050 (au->client_condition != NULL &&
1051 !expand_check_condition(au->client_condition, au->name,
1052 US"client authenticator")))
1053 {
1054 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1055 au->name,
1056 (au->client)? "client_condition is false" :
1057 "not configured as a client");
1058 continue;
1059 }
1060
1061 /* Loop to scan supported server mechanisms */
1062
1063 while (*p)
1064 {
1065 int rc;
1066 int len = Ustrlen(au->public_name);
1067 while (isspace(*p)) p++;
1068
1069 if (strncmpic(au->public_name, p, len) != 0 ||
1070 (p[len] != 0 && !isspace(p[len])))
1071 {
1072 while (*p != 0 && !isspace(*p)) p++;
1073 continue;
1074 }
1075
1076 /* Found data for a listed mechanism. Call its client entry. Set
1077 a flag in the outblock so that data is overwritten after sending so
1078 that reflections don't show it. */
1079
1080 fail_reason = US"authentication attempt(s) failed";
1081 obp->authenticating = TRUE;
1082 rc = (au->info->clientcode)(au, ibp, obp,
1083 ob->command_timeout, buffer, bufsize);
1084 obp->authenticating = FALSE;
1085 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1086 au->name, rc);
1087
1088 /* A temporary authentication failure must hold up delivery to
1089 this host. After a permanent authentication failure, we carry on
1090 to try other authentication methods. If all fail hard, try to
1091 deliver the message unauthenticated unless require_auth was set. */
1092
1093 switch(rc)
1094 {
1095 case OK:
1096 smtp_authenticated = TRUE; /* stops the outer loop */
1097 client_authenticator = au->name;
1098 if (au->set_client_id != NULL)
1099 client_authenticated_id = expand_string(au->set_client_id);
1100 break;
1101
1102 /* Failure after writing a command */
1103
1104 case FAIL_SEND:
1105 return FAIL_SEND;
1106
1107 /* Failure after reading a response */
1108
1109 case FAIL:
1110 if (errno != 0 || buffer[0] != '5') return FAIL;
1111 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1112 au->name, host->name, host->address, buffer);
1113 break;
1114
1115 /* Failure by some other means. In effect, the authenticator
1116 decided it wasn't prepared to handle this case. Typically this
1117 is the result of "fail" in an expansion string. Do we need to
1118 log anything here? Feb 2006: a message is now put in the buffer
1119 if logging is required. */
1120
1121 case CANCELLED:
1122 if (*buffer != 0)
1123 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1124 "authentication H=%s [%s] %s", au->name, host->name,
1125 host->address, buffer);
1126 break;
1127
1128 /* Internal problem, message in buffer. */
1129
1130 case ERROR:
1131 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1132 DEFER, FALSE);
1133 return ERROR;
1134 }
1135
1136 break; /* If not authenticated, try next authenticator */
1137 } /* Loop for scanning supported server mechanisms */
1138 } /* Loop for further authenticators */
1139 }
1140 }
1141
1142 /* If we haven't authenticated, but are required to, give up. */
1143
1144 if (require_auth == OK && !smtp_authenticated)
1145 {
1146 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1147 string_sprintf("authentication required but %s", fail_reason), DEFER,
1148 FALSE);
1149 return DEFER;
1150 }
1151
1152 return OK;
1153 }
1154
1155
1156 /* Construct AUTH appendix string for MAIL TO */
1157 /*
1158 Arguments
1159 buffer to build string
1160 addrlist chain of potential addresses to deliver
1161 ob transport options
1162
1163 Globals smtp_authenticated
1164 client_authenticated_sender
1165 Return True on error, otherwise buffer has (possibly empty) terminated string
1166 */
1167
1168 BOOL
1169 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1170 smtp_transport_options_block *ob)
1171 {
1172 uschar *local_authenticated_sender = authenticated_sender;
1173
1174 #ifdef notdef
1175 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1176 #endif
1177
1178 if (ob->authenticated_sender != NULL)
1179 {
1180 uschar *new = expand_string(ob->authenticated_sender);
1181 if (new == NULL)
1182 {
1183 if (!expand_string_forcedfail)
1184 {
1185 uschar *message = string_sprintf("failed to expand "
1186 "authenticated_sender: %s", expand_string_message);
1187 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1188 return TRUE;
1189 }
1190 }
1191 else if (new[0] != 0) local_authenticated_sender = new;
1192 }
1193
1194 /* Add the authenticated sender address if present */
1195
1196 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1197 local_authenticated_sender != NULL)
1198 {
1199 string_format(buffer, bufsize, " AUTH=%s",
1200 auth_xtextencode(local_authenticated_sender,
1201 Ustrlen(local_authenticated_sender)));
1202 client_authenticated_sender = string_copy(local_authenticated_sender);
1203 }
1204 else
1205 *buffer= 0;
1206
1207 return FALSE;
1208 }
1209
1210
1211
1212 #ifdef SUPPORT_DANE
1213 /* Lookup TLSA record for host/port.
1214 Return: OK success with dnssec; DANE mode
1215 DEFER Do not use this host now, may retry later
1216 FAIL_FORCED No TLSA record; DANE not usable
1217 FAIL Do not use this connection
1218 */
1219
1220 int
1221 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1222 {
1223 /* move this out to host.c given the similarity to dns_lookup() ? */
1224 uschar buffer[300];
1225 const uschar * fullname = buffer;
1226 int rc;
1227 BOOL sec;
1228
1229 /* TLSA lookup string */
1230 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1231
1232 rc = dns_lookup(dnsa, buffer, T_TLSA, &fullname);
1233 sec = dns_is_secure(dnsa);
1234 DEBUG(D_transport)
1235 debug_printf("TLSA lookup ret %d %sDNSSEC\n", rc, sec ? "" : "not ");
1236
1237 switch (rc)
1238 {
1239 case DNS_AGAIN:
1240 return DEFER; /* just defer this TLS'd conn */
1241
1242 case DNS_SUCCEED:
1243 if (sec) return OK;
1244 log_write(0, LOG_MAIN,
1245 "DANE error: TLSA lookup for %s not DNSSEC", host->name);
1246 /*FALLTRHOUGH*/
1247
1248 case DNS_NODATA: /* no TLSA RR for this lookup */
1249 case DNS_NOMATCH: /* no records at all for this lookup */
1250 return dane_required ? FAIL : FAIL_FORCED;
1251
1252 default:
1253 case DNS_FAIL:
1254 return dane_required ? FAIL : DEFER;
1255 }
1256 }
1257 #endif
1258
1259
1260
1261 typedef struct smtp_compare_s
1262 {
1263 uschar *current_sender_address;
1264 struct transport_instance *tblock;
1265 } smtp_compare_t;
1266
1267
1268 /* Create a unique string that identifies this message, it is based on
1269 sender_address, helo_data and tls_certificate if enabled.
1270 */
1271
1272 static uschar *
1273 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1274 {
1275 address_item * addr1;
1276 uschar * if1 = US"";
1277 uschar * helo1 = US"";
1278 #ifdef SUPPORT_TLS
1279 uschar * tlsc1 = US"";
1280 #endif
1281 uschar * save_sender_address = sender_address;
1282 uschar * local_identity = NULL;
1283 smtp_transport_options_block * ob =
1284 (smtp_transport_options_block *)tblock->options_block;
1285
1286 sender_address = sender;
1287
1288 addr1 = deliver_make_addr (sender, TRUE);
1289 deliver_set_expansions(addr1);
1290
1291 if (ob->interface)
1292 if1 = expand_string(ob->interface);
1293
1294 if (ob->helo_data)
1295 helo1 = expand_string(ob->helo_data);
1296
1297 #ifdef SUPPORT_TLS
1298 if (ob->tls_certificate)
1299 tlsc1 = expand_string(ob->tls_certificate);
1300 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1301 #else
1302 local_identity = string_sprintf ("%s^%s", if1, helo1);
1303 #endif
1304
1305 deliver_set_expansions(NULL);
1306 sender_address = save_sender_address;
1307
1308 return local_identity;
1309 }
1310
1311
1312
1313 /* This routine is a callback that is called from transport_check_waiting.
1314 This function will evaluate the incoming message versus the previous
1315 message. If the incoming message is using a different local identity then
1316 we will veto this new message. */
1317
1318 static BOOL
1319 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1320 {
1321 uschar * message_local_identity,
1322 * current_local_identity,
1323 * new_sender_address;
1324
1325 current_local_identity =
1326 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1327
1328 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1329 return 0;
1330
1331 message_local_identity =
1332 smtp_local_identity(new_sender_address, s_compare->tblock);
1333
1334 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1335 }
1336
1337
1338
1339 static unsigned
1340 ehlo_response(uschar * buf, unsigned checks)
1341 {
1342 size_t bsize = Ustrlen(buf);
1343
1344 #ifdef SUPPORT_TLS
1345 if ( checks & OPTION_TLS
1346 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1347 checks &= ~OPTION_TLS;
1348
1349 # ifdef EXPERIMENTAL_REQUIRETLS
1350 if ( checks & OPTION_REQUIRETLS
1351 && pcre_exec(regex_REQUIRETLS, NULL, CS buf,bsize, 0, PCRE_EOPT, NULL,0) < 0)
1352 checks &= ~OPTION_REQUIRETLS;
1353 # endif
1354 #endif
1355
1356 if ( checks & OPTION_IGNQ
1357 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1358 PCRE_EOPT, NULL, 0) < 0)
1359 checks &= ~OPTION_IGNQ;
1360
1361 if ( checks & OPTION_CHUNKING
1362 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1363 checks &= ~OPTION_CHUNKING;
1364
1365 #ifndef DISABLE_PRDR
1366 if ( checks & OPTION_PRDR
1367 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1368 checks &= ~OPTION_PRDR;
1369 #endif
1370
1371 #ifdef SUPPORT_I18N
1372 if ( checks & OPTION_UTF8
1373 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1374 checks &= ~OPTION_UTF8;
1375 #endif
1376
1377 if ( checks & OPTION_DSN
1378 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1379 checks &= ~OPTION_DSN;
1380
1381 if ( checks & OPTION_PIPE
1382 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1383 PCRE_EOPT, NULL, 0) < 0)
1384 checks &= ~OPTION_PIPE;
1385
1386 if ( checks & OPTION_SIZE
1387 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1388 checks &= ~OPTION_SIZE;
1389
1390 return checks;
1391 }
1392
1393
1394
1395 /* Callback for emitting a BDAT data chunk header.
1396
1397 If given a nonzero size, first flush any buffered SMTP commands
1398 then emit the command.
1399
1400 Reap previous SMTP command responses if requested, and always reap
1401 the response from a previous BDAT command.
1402
1403 Args:
1404 tctx transport context
1405 chunk_size value for SMTP BDAT command
1406 flags
1407 tc_chunk_last add LAST option to SMTP BDAT command
1408 tc_reap_prev reap response to previous SMTP commands
1409
1410 Returns: OK or ERROR
1411 */
1412
1413 static int
1414 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1415 unsigned flags)
1416 {
1417 smtp_transport_options_block * ob =
1418 (smtp_transport_options_block *)(tctx->tblock->options_block);
1419 smtp_context * sx = tctx->smtp_context;
1420 int cmd_count = 0;
1421 int prev_cmd_count;
1422
1423 /* Write SMTP chunk header command. If not reaping responses, note that
1424 there may be more writes (like, the chunk data) done soon. */
1425
1426 if (chunk_size > 0)
1427 {
1428 if((cmd_count = smtp_write_command(&sx->outblock,
1429 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1430 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1431 ) < 0) return ERROR;
1432 if (flags & tc_chunk_last)
1433 data_command = string_copy(big_buffer); /* Save for later error message */
1434 }
1435
1436 prev_cmd_count = cmd_count += sx->cmd_count;
1437
1438 /* Reap responses for any previous, but not one we just emitted */
1439
1440 if (chunk_size > 0)
1441 prev_cmd_count--;
1442 if (sx->pending_BDAT)
1443 prev_cmd_count--;
1444
1445 if (flags & tc_reap_prev && prev_cmd_count > 0)
1446 {
1447 DEBUG(D_transport) debug_printf("look for %d responses"
1448 " for previous pipelined cmds\n", prev_cmd_count);
1449
1450 switch(sync_responses(sx, prev_cmd_count, 0))
1451 {
1452 case 1: /* 2xx (only) => OK */
1453 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1454 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1455 case 0: break; /* No 2xx or 5xx, but no probs */
1456
1457 case -1: /* Timeout on RCPT */
1458 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1459 }
1460 cmd_count = 1;
1461 if (!sx->pending_BDAT)
1462 pipelining_active = FALSE;
1463 }
1464
1465 /* Reap response for an outstanding BDAT */
1466
1467 if (sx->pending_BDAT)
1468 {
1469 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1470
1471 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1472 ob->command_timeout))
1473 {
1474 if (errno == 0 && sx->buffer[0] == '4')
1475 {
1476 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1477 sx->addrlist->more_errno |=
1478 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1479 }
1480 return ERROR;
1481 }
1482 cmd_count--;
1483 sx->pending_BDAT = FALSE;
1484 pipelining_active = FALSE;
1485 }
1486 else if (chunk_size > 0)
1487 sx->pending_BDAT = TRUE;
1488
1489
1490 sx->cmd_count = cmd_count;
1491 return OK;
1492 }
1493
1494
1495
1496 /*************************************************
1497 * Make connection for given message *
1498 *************************************************/
1499
1500 /*
1501 Arguments:
1502 ctx connection context
1503 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1504 a second attempt after TLS initialization fails
1505
1506 Returns: OK - the connection was made and the delivery attempted;
1507 fd is set in the conn context, tls_out set up.
1508 DEFER - the connection could not be made, or something failed
1509 while setting up the SMTP session, or there was a
1510 non-message-specific error, such as a timeout.
1511 ERROR - helo_data or add_headers or authenticated_sender is
1512 specified for this transport, and the string failed
1513 to expand
1514 */
1515 int
1516 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1517 {
1518 #if defined(SUPPORT_TLS) && defined(SUPPORT_DANE)
1519 dns_answer tlsa_dnsa;
1520 #endif
1521 BOOL pass_message = FALSE;
1522 uschar * message = NULL;
1523 int yield = OK;
1524 int rc;
1525
1526 sx->ob = (smtp_transport_options_block *) sx->tblock->options_block;
1527
1528 sx->lmtp = strcmpic(sx->ob->protocol, US"lmtp") == 0;
1529 sx->smtps = strcmpic(sx->ob->protocol, US"smtps") == 0;
1530 sx->ok = FALSE;
1531 sx->send_rset = TRUE;
1532 sx->send_quit = TRUE;
1533 sx->setting_up = TRUE;
1534 sx->esmtp = TRUE;
1535 sx->esmtp_sent = FALSE;
1536 #ifdef SUPPORT_I18N
1537 sx->utf8_needed = FALSE;
1538 #endif
1539 sx->dsn_all_lasthop = TRUE;
1540 #if defined(SUPPORT_TLS) && defined(SUPPORT_DANE)
1541 sx->dane = FALSE;
1542 sx->dane_required =
1543 verify_check_given_host(&sx->ob->hosts_require_dane, sx->host) == OK;
1544 #endif
1545
1546 if ((sx->max_rcpt = sx->tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1547 sx->peer_offered = 0;
1548 sx->avoid_option = 0;
1549 sx->igquotstr = US"";
1550 if (!sx->helo_data) sx->helo_data = sx->ob->helo_data;
1551 #ifdef EXPERIMENTAL_DSN_INFO
1552 sx->smtp_greeting = NULL;
1553 sx->helo_response = NULL;
1554 #endif
1555
1556 smtp_command = US"initial connection";
1557 sx->buffer[0] = '\0';
1558
1559 /* Set up the buffer for reading SMTP response packets. */
1560
1561 sx->inblock.buffer = sx->inbuffer;
1562 sx->inblock.buffersize = sizeof(sx->inbuffer);
1563 sx->inblock.ptr = sx->inbuffer;
1564 sx->inblock.ptrend = sx->inbuffer;
1565
1566 /* Set up the buffer for holding SMTP commands while pipelining */
1567
1568 sx->outblock.buffer = sx->outbuffer;
1569 sx->outblock.buffersize = sizeof(sx->outbuffer);
1570 sx->outblock.ptr = sx->outbuffer;
1571 sx->outblock.cmd_count = 0;
1572 sx->outblock.authenticating = FALSE;
1573
1574 /* Reset the parameters of a TLS session. */
1575
1576 tls_out.bits = 0;
1577 tls_out.cipher = NULL; /* the one we may use for this transport */
1578 tls_out.ourcert = NULL;
1579 tls_out.peercert = NULL;
1580 tls_out.peerdn = NULL;
1581 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1582 tls_out.sni = NULL;
1583 #endif
1584 tls_out.ocsp = OCSP_NOT_REQ;
1585
1586 /* Flip the legacy TLS-related variables over to the outbound set in case
1587 they're used in the context of the transport. Don't bother resetting
1588 afterward (when being used by a transport) as we're in a subprocess.
1589 For verify, unflipped once the callout is dealt with */
1590
1591 tls_modify_variables(&tls_out);
1592
1593 #ifndef SUPPORT_TLS
1594 if (sx->smtps)
1595 {
1596 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1597 DEFER, FALSE);
1598 return ERROR;
1599 }
1600 #endif
1601
1602 /* Make a connection to the host if this isn't a continued delivery, and handle
1603 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1604 specially so they can be identified for retries. */
1605
1606 if (!continue_hostname)
1607 {
1608 if (sx->verify)
1609 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->interface, sx->port);
1610
1611 /* Get the actual port the connection will use, into sx->host */
1612
1613 smtp_port_for_connect(sx->host, sx->port);
1614
1615 #if defined(SUPPORT_TLS) && defined(SUPPORT_DANE)
1616 /* Do TLSA lookup for DANE */
1617 {
1618 tls_out.dane_verified = FALSE;
1619 tls_out.tlsa_usage = 0;
1620
1621 if (sx->host->dnssec == DS_YES)
1622 {
1623 if( sx->dane_required
1624 || verify_check_given_host(&sx->ob->hosts_try_dane, sx->host) == OK
1625 )
1626 switch (rc = tlsa_lookup(sx->host, &tlsa_dnsa, sx->dane_required))
1627 {
1628 case OK: sx->dane = TRUE;
1629 sx->ob->tls_tempfail_tryclear = FALSE;
1630 break;
1631 case FAIL_FORCED: break;
1632 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1633 string_sprintf("DANE error: tlsa lookup %s",
1634 rc == DEFER ? "DEFER" : "FAIL"),
1635 rc, FALSE);
1636 # ifndef DISABLE_EVENT
1637 (void) event_raise(sx->tblock->event_action,
1638 US"dane:fail", sx->dane_required
1639 ? US"dane-required" : US"dnssec-invalid");
1640 # endif
1641 return rc;
1642 }
1643 }
1644 else if (sx->dane_required)
1645 {
1646 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1647 string_sprintf("DANE error: %s lookup not DNSSEC", sx->host->name),
1648 FAIL, FALSE);
1649 # ifndef DISABLE_EVENT
1650 (void) event_raise(sx->tblock->event_action,
1651 US"dane:fail", US"dane-required");
1652 # endif
1653 return FAIL;
1654 }
1655 }
1656 #endif /*DANE*/
1657
1658 /* Make the TCP connection */
1659
1660 sx->cctx.sock =
1661 smtp_connect(sx->host, sx->host_af, sx->interface,
1662 sx->ob->connect_timeout, sx->tblock);
1663 sx->cctx.tls_ctx = NULL;
1664 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
1665
1666 if (sx->cctx.sock < 0)
1667 {
1668 uschar * msg = NULL;
1669 if (sx->verify)
1670 {
1671 msg = US strerror(errno);
1672 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
1673 }
1674 set_errno_nohost(sx->addrlist,
1675 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1676 sx->verify ? string_sprintf("could not connect: %s", msg)
1677 : NULL,
1678 DEFER, FALSE);
1679 sx->send_quit = FALSE;
1680 return DEFER;
1681 }
1682
1683 /* Expand the greeting message while waiting for the initial response. (Makes
1684 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1685 delayed till here so that $sending_interface and $sending_port are set. */
1686
1687 if (sx->helo_data)
1688 if (!(sx->helo_data = expand_string(sx->helo_data)))
1689 if (sx->verify)
1690 log_write(0, LOG_MAIN|LOG_PANIC,
1691 "<%s>: failed to expand transport's helo_data value for callout: %s",
1692 sx->addrlist->address, expand_string_message);
1693
1694 #ifdef SUPPORT_I18N
1695 if (sx->helo_data)
1696 {
1697 expand_string_message = NULL;
1698 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
1699 &expand_string_message)),
1700 expand_string_message)
1701 if (sx->verify)
1702 log_write(0, LOG_MAIN|LOG_PANIC,
1703 "<%s>: failed to expand transport's helo_data value for callout: %s",
1704 sx->addrlist->address, expand_string_message);
1705 else
1706 sx->helo_data = NULL;
1707 }
1708 #endif
1709
1710 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1711 is nevertheless a reasonably clean way of programming this kind of logic,
1712 where you want to escape on any error. */
1713
1714 if (!sx->smtps)
1715 {
1716 BOOL good_response;
1717
1718 #ifdef TCP_QUICKACK
1719 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1720 #endif
1721 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1722 '2', sx->ob->command_timeout);
1723 #ifdef EXPERIMENTAL_DSN_INFO
1724 sx->smtp_greeting = string_copy(sx->buffer);
1725 #endif
1726 if (!good_response) goto RESPONSE_FAILED;
1727
1728 #ifndef DISABLE_EVENT
1729 {
1730 uschar * s;
1731 lookup_dnssec_authenticated = sx->host->dnssec==DS_YES ? US"yes"
1732 : sx->host->dnssec==DS_NO ? US"no" : NULL;
1733 s = event_raise(sx->tblock->event_action, US"smtp:connect", sx->buffer);
1734 if (s)
1735 {
1736 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
1737 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1738 DEFER, FALSE);
1739 yield = DEFER;
1740 goto SEND_QUIT;
1741 }
1742 }
1743 #endif
1744
1745 /* Now check if the helo_data expansion went well, and sign off cleanly if
1746 it didn't. */
1747
1748 if (!sx->helo_data)
1749 {
1750 message = string_sprintf("failed to expand helo_data: %s",
1751 expand_string_message);
1752 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1753 yield = DEFER;
1754 goto SEND_QUIT;
1755 }
1756 }
1757
1758 /** Debugging without sending a message
1759 sx->addrlist->transport_return = DEFER;
1760 goto SEND_QUIT;
1761 **/
1762
1763 /* Errors that occur after this point follow an SMTP command, which is
1764 left in big_buffer by smtp_write_command() for use in error messages. */
1765
1766 smtp_command = big_buffer;
1767
1768 /* Tell the remote who we are...
1769
1770 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1771 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1772 greeting is of this form. The assumption was that the far end supports it
1773 properly... but experience shows that there are some that give 5xx responses,
1774 even though the banner includes "ESMTP" (there's a bloody-minded one that
1775 says "ESMTP not spoken here"). Cope with that case.
1776
1777 September 2000: Time has passed, and it seems reasonable now to always send
1778 EHLO at the start. It is also convenient to make the change while installing
1779 the TLS stuff.
1780
1781 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1782 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1783 would be no way to send out the mails, so there is now a host list
1784 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1785 PIPELINING problem as well. Maybe it can also be useful to cure other
1786 problems with broken servers.
1787
1788 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1789 Then somebody tried it with a Microsoft mailer... It seems that all other
1790 mailers use upper case for some reason (the RFC is quite clear about case
1791 independence) so, for peace of mind, I gave in. */
1792
1793 sx->esmtp = verify_check_given_host(&sx->ob->hosts_avoid_esmtp, sx->host) != OK;
1794
1795 /* Alas; be careful, since this goto is not an error-out, so conceivably
1796 we might set data between here and the target which we assume to exist
1797 and be usable. I can see this coming back to bite us. */
1798 #ifdef SUPPORT_TLS
1799 if (sx->smtps)
1800 {
1801 smtp_peer_options |= OPTION_TLS;
1802 suppress_tls = FALSE;
1803 sx->ob->tls_tempfail_tryclear = FALSE;
1804 smtp_command = US"SSL-on-connect";
1805 goto TLS_NEGOTIATE;
1806 }
1807 #endif
1808
1809 if (sx->esmtp)
1810 {
1811 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "%s %s\r\n",
1812 sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
1813 goto SEND_FAILED;
1814 sx->esmtp_sent = TRUE;
1815 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1816 sx->ob->command_timeout))
1817 {
1818 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
1819 {
1820 #ifdef EXPERIMENTAL_DSN_INFO
1821 sx->helo_response = string_copy(sx->buffer);
1822 #endif
1823 goto RESPONSE_FAILED;
1824 }
1825 sx->esmtp = FALSE;
1826 }
1827 #ifdef EXPERIMENTAL_DSN_INFO
1828 sx->helo_response = string_copy(sx->buffer);
1829 #endif
1830 }
1831 else
1832 DEBUG(D_transport)
1833 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1834
1835 if (!sx->esmtp)
1836 {
1837 BOOL good_response;
1838 int n = sizeof(sx->buffer);
1839 uschar * rsp = sx->buffer;
1840
1841 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
1842 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
1843
1844 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
1845 goto SEND_FAILED;
1846 good_response = smtp_read_response(&sx->inblock, rsp, n,
1847 '2', sx->ob->command_timeout);
1848 #ifdef EXPERIMENTAL_DSN_INFO
1849 sx->helo_response = string_copy(rsp);
1850 #endif
1851 if (!good_response)
1852 {
1853 /* Handle special logging for a closed connection after HELO
1854 when had previously sent EHLO */
1855
1856 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1857 {
1858 errno = ERRNO_SMTPCLOSED;
1859 goto EHLOHELO_FAILED;
1860 }
1861 memmove(sx->buffer, rsp, Ustrlen(rsp));
1862 goto RESPONSE_FAILED;
1863 }
1864 }
1865
1866 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
1867
1868 if (sx->esmtp || sx->lmtp)
1869 {
1870 sx->peer_offered = ehlo_response(sx->buffer,
1871 OPTION_TLS /* others checked later */
1872 );
1873
1874 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1875
1876 #ifdef SUPPORT_TLS
1877 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
1878 #endif
1879 }
1880 }
1881
1882 /* For continuing deliveries down the same channel, having re-exec'd the socket
1883 is the standard input; for a socket held open from verify it is recorded
1884 in the cutthrough context block. Either way we don't need to redo EHLO here
1885 (but may need to do so for TLS - see below).
1886 Set up the pointer to where subsequent commands will be left, for
1887 error messages. Note that smtp_peer_options will have been
1888 set from the command line if they were set in the process that passed the
1889 connection on. */
1890
1891 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1892 as the continue goes via transport_pass_socket() and doublefork and exec.
1893 It does not wait. Unclear how we keep separate host's responses
1894 separate - we could match up by host ip+port as a bodge. */
1895
1896 else
1897 {
1898 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
1899 {
1900 sx->cctx = cutthrough.cctx;
1901 sx->host->port = sx->port = cutthrough.host.port;
1902 }
1903 else
1904 {
1905 sx->cctx.sock = 0; /* stdin */
1906 sx->cctx.tls_ctx = NULL;
1907 smtp_port_for_connect(sx->host, sx->port); /* Record the port that was used */
1908 }
1909 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
1910 smtp_command = big_buffer;
1911 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
1912
1913 /* For a continued connection with TLS being proxied for us, or a
1914 held-open verify connection with TLS, nothing more to do. */
1915
1916 if ( continue_proxy_cipher
1917 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
1918 && cutthrough.is_tls)
1919 )
1920 {
1921 sx->peer_offered = smtp_peer_options;
1922 pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
1923 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
1924 continue_proxy_cipher ? "proxied" : "verify conn with");
1925 return OK;
1926 }
1927 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
1928 }
1929
1930 /* If TLS is available on this connection, whether continued or not, attempt to
1931 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1932 send another EHLO - the server may give a different answer in secure mode. We
1933 use a separate buffer for reading the response to STARTTLS so that if it is
1934 negative, the original EHLO data is available for subsequent analysis, should
1935 the client not be required to use TLS. If the response is bad, copy the buffer
1936 for error analysis. */
1937
1938 #ifdef SUPPORT_TLS
1939 if ( smtp_peer_options & OPTION_TLS
1940 && !suppress_tls
1941 && verify_check_given_host(&sx->ob->hosts_avoid_tls, sx->host) != OK
1942 && ( !sx->verify
1943 || verify_check_given_host(&sx->ob->hosts_verify_avoid_tls, sx->host) != OK
1944 ) )
1945 {
1946 uschar buffer2[4096];
1947 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "STARTTLS\r\n") < 0)
1948 goto SEND_FAILED;
1949
1950 /* If there is an I/O error, transmission of this message is deferred. If
1951 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1952 false, we also defer. However, if there is a temporary rejection of STARTTLS
1953 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1954 STARTTLS, we carry on. This means we will try to send the message in clear,
1955 unless the host is in hosts_require_tls (tested below). */
1956
1957 if (!smtp_read_response(&sx->inblock, buffer2, sizeof(buffer2), '2',
1958 sx->ob->command_timeout))
1959 {
1960 if ( errno != 0
1961 || buffer2[0] == 0
1962 || (buffer2[0] == '4' && !sx->ob->tls_tempfail_tryclear)
1963 )
1964 {
1965 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
1966 sx->buffer[sizeof(sx->buffer)-1] = '\0';
1967 goto RESPONSE_FAILED;
1968 }
1969 }
1970
1971 /* STARTTLS accepted: try to negotiate a TLS session. */
1972
1973 else
1974 TLS_NEGOTIATE:
1975 {
1976 address_item * addr;
1977 uschar * errstr;
1978 sx->cctx.tls_ctx = tls_client_start(sx->cctx.sock, sx->host,
1979 sx->addrlist, sx->tblock,
1980 # ifdef SUPPORT_DANE
1981 sx->dane ? &tlsa_dnsa : NULL,
1982 # endif
1983 &tls_out, &errstr);
1984
1985 if (!sx->cctx.tls_ctx)
1986 {
1987 /* TLS negotiation failed; give an error. From outside, this function may
1988 be called again to try in clear on a new connection, if the options permit
1989 it for this host. */
1990
1991 # ifdef SUPPORT_DANE
1992 if (sx->dane)
1993 {
1994 log_write(0, LOG_MAIN,
1995 "DANE attempt failed; TLS connection to %s [%s]: %s",
1996 sx->host->name, sx->host->address, errstr);
1997 # ifndef DISABLE_EVENT
1998 (void) event_raise(sx->tblock->event_action,
1999 US"dane:fail", US"validation-failure"); /* could do with better detail */
2000 # endif
2001 }
2002 # endif
2003
2004 errno = ERRNO_TLSFAILURE;
2005 message = string_sprintf("TLS session: %s", errstr);
2006 sx->send_quit = FALSE;
2007 goto TLS_FAILED;
2008 }
2009
2010 /* TLS session is set up */
2011
2012 smtp_peer_options_wrap = smtp_peer_options;
2013 for (addr = sx->addrlist; addr; addr = addr->next)
2014 if (addr->transport_return == PENDING_DEFER)
2015 {
2016 addr->cipher = tls_out.cipher;
2017 addr->ourcert = tls_out.ourcert;
2018 addr->peercert = tls_out.peercert;
2019 addr->peerdn = tls_out.peerdn;
2020 addr->ocsp = tls_out.ocsp;
2021 }
2022 }
2023 }
2024
2025 /* if smtps, we'll have smtp_command set to something else; always safe to
2026 reset it here. */
2027 smtp_command = big_buffer;
2028
2029 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2030 helo_data is null, we are dealing with a connection that was passed from
2031 another process, and so we won't have expanded helo_data above. We have to
2032 expand it here. $sending_ip_address and $sending_port are set up right at the
2033 start of the Exim process (in exim.c). */
2034
2035 if (tls_out.active.sock >= 0)
2036 {
2037 char *greeting_cmd;
2038 BOOL good_response;
2039
2040 if (!sx->helo_data && !(sx->helo_data = expand_string(sx->ob->helo_data)))
2041 {
2042 uschar *message = string_sprintf("failed to expand helo_data: %s",
2043 expand_string_message);
2044 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2045 yield = DEFER;
2046 goto SEND_QUIT;
2047 }
2048
2049 /* For SMTPS we need to wait for the initial OK response. */
2050 if (sx->smtps)
2051 {
2052 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
2053 '2', sx->ob->command_timeout);
2054 #ifdef EXPERIMENTAL_DSN_INFO
2055 sx->smtp_greeting = string_copy(sx->buffer);
2056 #endif
2057 if (!good_response) goto RESPONSE_FAILED;
2058 }
2059
2060 if (sx->esmtp)
2061 greeting_cmd = "EHLO";
2062 else
2063 {
2064 greeting_cmd = "HELO";
2065 DEBUG(D_transport)
2066 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2067 }
2068
2069 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "%s %s\r\n",
2070 sx->lmtp ? "LHLO" : greeting_cmd, sx->helo_data) < 0)
2071 goto SEND_FAILED;
2072 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
2073 '2', sx->ob->command_timeout);
2074 #ifdef EXPERIMENTAL_DSN_INFO
2075 sx->helo_response = string_copy(sx->buffer);
2076 #endif
2077 if (!good_response) goto RESPONSE_FAILED;
2078 smtp_peer_options = 0;
2079 }
2080
2081 /* If the host is required to use a secure channel, ensure that we
2082 have one. */
2083
2084 else if ( sx->smtps
2085 # ifdef SUPPORT_DANE
2086 || sx->dane
2087 # endif
2088 # ifdef EXPERIMENTAL_REQUIRETLS
2089 || tls_requiretls & REQUIRETLS_MSG
2090 # endif
2091 || verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
2092 )
2093 {
2094 errno =
2095 # ifdef EXPERIMENTAL_REQUIRETLS
2096 tls_requiretls & REQUIRETLS_MSG ? ERRNO_REQUIRETLS :
2097 # endif
2098 ERRNO_TLSREQUIRED;
2099 message = string_sprintf("a TLS session is required, but %s",
2100 smtp_peer_options & OPTION_TLS
2101 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2102 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2103 if (sx->dane)
2104 (void) event_raise(sx->tblock->event_action, US"dane:fail",
2105 smtp_peer_options & OPTION_TLS
2106 ? US"validation-failure" /* could do with better detail */
2107 : US"starttls-not-supported");
2108 # endif
2109 goto TLS_FAILED;
2110 }
2111 #endif /*SUPPORT_TLS*/
2112
2113 /* If TLS is active, we have just started it up and re-done the EHLO command,
2114 so its response needs to be analyzed. If TLS is not active and this is a
2115 continued session down a previously-used socket, we haven't just done EHLO, so
2116 we skip this. */
2117
2118 if (continue_hostname == NULL
2119 #ifdef SUPPORT_TLS
2120 || tls_out.active.sock >= 0
2121 #endif
2122 )
2123 {
2124 if (sx->esmtp || sx->lmtp)
2125 {
2126 sx->peer_offered = ehlo_response(sx->buffer,
2127 0 /* no TLS */
2128 | (sx->lmtp && sx->ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2129 | OPTION_CHUNKING
2130 | OPTION_PRDR
2131 #ifdef SUPPORT_I18N
2132 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2133 /*XXX if we hand peercaps on to continued-conn processes,
2134 must not depend on this addr */
2135 #endif
2136 | OPTION_DSN
2137 | OPTION_PIPE
2138 | (sx->ob->size_addition >= 0 ? OPTION_SIZE : 0)
2139 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS)
2140 | (tls_requiretls & REQUIRETLS_MSG ? OPTION_REQUIRETLS : 0)
2141 #endif
2142 );
2143
2144 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2145 lmtp_ignore_quota option was set. */
2146
2147 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2148
2149 /* If the response to EHLO specified support for the SIZE parameter, note
2150 this, provided size_addition is non-negative. */
2151
2152 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2153
2154 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2155 the current host, esmtp will be false, so PIPELINING can never be used. If
2156 the current host matches hosts_avoid_pipelining, don't do it. */
2157
2158 if ( sx->peer_offered & OPTION_PIPE
2159 && verify_check_given_host(&sx->ob->hosts_avoid_pipelining, sx->host) != OK)
2160 smtp_peer_options |= OPTION_PIPE;
2161
2162 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2163 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2164
2165 if ( sx->peer_offered & OPTION_CHUNKING
2166 && verify_check_given_host(&sx->ob->hosts_try_chunking, sx->host) != OK)
2167 sx->peer_offered &= ~OPTION_CHUNKING;
2168
2169 if (sx->peer_offered & OPTION_CHUNKING)
2170 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2171
2172 #ifndef DISABLE_PRDR
2173 if ( sx->peer_offered & OPTION_PRDR
2174 && verify_check_given_host(&sx->ob->hosts_try_prdr, sx->host) != OK)
2175 sx->peer_offered &= ~OPTION_PRDR;
2176
2177 if (sx->peer_offered & OPTION_PRDR)
2178 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2179 #endif
2180
2181 /* Note if the server supports DSN */
2182 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2183 DEBUG(D_transport) debug_printf("%susing DSN\n",
2184 sx->peer_offered & OPTION_DSN ? "" : "not ");
2185
2186 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS)
2187 if (sx->peer_offered & OPTION_REQUIRETLS)
2188 {
2189 smtp_peer_options |= OPTION_REQUIRETLS;
2190 DEBUG(D_transport) debug_printf(
2191 tls_requiretls & REQUIRETLS_MSG
2192 ? "using REQUIRETLS\n" : "REQUIRETLS offered\n");
2193 }
2194 #endif
2195
2196 /* Note if the response to EHLO specifies support for the AUTH extension.
2197 If it has, check that this host is one we want to authenticate to, and do
2198 the business. The host name and address must be available when the
2199 authenticator's client driver is running. */
2200
2201 switch (yield = smtp_auth(sx->buffer, sizeof(sx->buffer), sx->addrlist, sx->host,
2202 sx->ob, sx->esmtp, &sx->inblock, &sx->outblock))
2203 {
2204 default: goto SEND_QUIT;
2205 case OK: break;
2206 case FAIL_SEND: goto SEND_FAILED;
2207 case FAIL: goto RESPONSE_FAILED;
2208 }
2209 }
2210 }
2211 pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2212
2213 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2214 message-specific. */
2215
2216 sx->setting_up = FALSE;
2217
2218 #ifdef SUPPORT_I18N
2219 if (sx->addrlist->prop.utf8_msg)
2220 {
2221 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2222 && !sx->addrlist->prop.utf8_downcvt_maybe;
2223 DEBUG(D_transport) if (!sx->utf8_needed)
2224 debug_printf("utf8: %s downconvert\n",
2225 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2226 }
2227
2228 /* If this is an international message we need the host to speak SMTPUTF8 */
2229 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2230 {
2231 errno = ERRNO_UTF8_FWD;
2232 goto RESPONSE_FAILED;
2233 }
2234 #endif
2235
2236 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS)
2237 /*XXX should tls_requiretls actually be per-addr? */
2238
2239 if ( tls_requiretls & REQUIRETLS_MSG
2240 && !(sx->peer_offered & OPTION_REQUIRETLS)
2241 )
2242 {
2243 sx->setting_up = TRUE;
2244 errno = ERRNO_REQUIRETLS;
2245 message = US"REQUIRETLS support is required from the server"
2246 " but it was not offered";
2247 DEBUG(D_transport) debug_printf("%s\n", message);
2248 goto TLS_FAILED;
2249 }
2250 #endif
2251
2252 return OK;
2253
2254
2255 {
2256 int code;
2257
2258 RESPONSE_FAILED:
2259 message = NULL;
2260 sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
2261 sx->buffer, &code, &message, &pass_message);
2262 yield = DEFER;
2263 goto FAILED;
2264
2265 SEND_FAILED:
2266 code = '4';
2267 message = US string_sprintf("send() to %s [%s] failed: %s",
2268 sx->host->name, sx->host->address, strerror(errno));
2269 sx->send_quit = FALSE;
2270 yield = DEFER;
2271 goto FAILED;
2272
2273 EHLOHELO_FAILED:
2274 code = '4';
2275 message = string_sprintf("Remote host closed connection in response to %s"
2276 " (EHLO response was: %s)", smtp_command, sx->buffer);
2277 sx->send_quit = FALSE;
2278 yield = DEFER;
2279 goto FAILED;
2280
2281 /* This label is jumped to directly when a TLS negotiation has failed,
2282 or was not done for a host for which it is required. Values will be set
2283 in message and errno, and setting_up will always be true. Treat as
2284 a temporary error. */
2285
2286 #ifdef SUPPORT_TLS
2287 TLS_FAILED:
2288 # ifdef EXPERIMENTAL_REQUIRETLS
2289 if (errno == ERRNO_REQUIRETLS)
2290 code = '5', yield = FAIL;
2291 /*XXX DSN will be labelled 500; prefer 530 5.7.4 */
2292 else
2293 # endif
2294 code = '4', yield = DEFER;
2295 goto FAILED;
2296 #endif
2297
2298 /* The failure happened while setting up the call; see if the failure was
2299 a 5xx response (this will either be on connection, or following HELO - a 5xx
2300 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2301 fail all addresses, as this host is never going to accept them. For other
2302 errors during setting up (timeouts or whatever), defer all addresses, and
2303 yield DEFER, so that the host is not tried again for a while.
2304
2305 XXX This peeking for another host feels like a layering violation. We want
2306 to note the host as unusable, but down here we shouldn't know if this was
2307 the last host to try for the addr(list). Perhaps the upper layer should be
2308 the one to do set_errno() ? The problem is that currently the addr is where
2309 errno etc. are stashed, but until we run out of hosts to try the errors are
2310 host-specific. Maybe we should enhance the host_item definition? */
2311
2312 FAILED:
2313 sx->ok = FALSE; /* For when reached by GOTO */
2314 set_errno(sx->addrlist, errno, message,
2315 sx->host->next
2316 ? DEFER
2317 : code == '5'
2318 #ifdef SUPPORT_I18N
2319 || errno == ERRNO_UTF8_FWD
2320 #endif
2321 ? FAIL : DEFER,
2322 pass_message, sx->host
2323 #ifdef EXPERIMENTAL_DSN_INFO
2324 , sx->smtp_greeting, sx->helo_response
2325 #endif
2326 );
2327 }
2328
2329
2330 SEND_QUIT:
2331
2332 if (sx->send_quit)
2333 (void)smtp_write_command(&sx->outblock, SCMD_FLUSH, "QUIT\r\n");
2334
2335 #ifdef SUPPORT_TLS
2336 if (sx->cctx.tls_ctx)
2337 {
2338 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
2339 sx->cctx.tls_ctx = NULL;
2340 }
2341 #endif
2342
2343 /* Close the socket, and return the appropriate value, first setting
2344 works because the NULL setting is passed back to the calling process, and
2345 remote_max_parallel is forced to 1 when delivering over an existing connection,
2346 */
2347
2348 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2349 if (sx->send_quit)
2350 {
2351 shutdown(sx->cctx.sock, SHUT_WR);
2352 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
2353 for (rc = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && rc > 0;)
2354 rc--; /* drain socket */
2355 sx->send_quit = FALSE;
2356 }
2357 (void)close(sx->cctx.sock);
2358 sx->cctx.sock = -1;
2359
2360 #ifndef DISABLE_EVENT
2361 (void) event_raise(sx->tblock->event_action, US"tcp:close", NULL);
2362 #endif
2363
2364 continue_transport = NULL;
2365 continue_hostname = NULL;
2366 return yield;
2367 }
2368
2369
2370
2371
2372 /* Create the string of options that will be appended to the MAIL FROM:
2373 in the connection context buffer */
2374
2375 static int
2376 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2377 {
2378 uschar * p = sx->buffer;
2379 address_item * addr;
2380 int address_count;
2381
2382 *p = 0;
2383
2384 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2385 send it, adding something to the message size to allow for imprecision
2386 and things that get added en route. Exim keeps the number of lines
2387 in a message, so we can give an accurate value for the original message, but we
2388 need some additional to handle added headers. (Double "." characters don't get
2389 included in the count.) */
2390
2391 if ( message_size > 0
2392 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
2393 {
2394 /*XXX problem here under spool_files_wireformat?
2395 Or just forget about lines? Or inflate by a fixed proportion? */
2396
2397 sprintf(CS p, " SIZE=%d", message_size+message_linecount+sx->ob->size_addition);
2398 while (*p) p++;
2399 }
2400
2401 #ifndef DISABLE_PRDR
2402 /* If it supports Per-Recipient Data Reponses, and we have omre than one recipient,
2403 request that */
2404
2405 sx->prdr_active = FALSE;
2406 if (sx->peer_offered & OPTION_PRDR)
2407 for (addr = addrlist; addr; addr = addr->next)
2408 if (addr->transport_return == PENDING_DEFER)
2409 {
2410 for (addr = addr->next; addr; addr = addr->next)
2411 if (addr->transport_return == PENDING_DEFER)
2412 { /* at least two recipients to send */
2413 sx->prdr_active = TRUE;
2414 sprintf(CS p, " PRDR"); p += 5;
2415 break;
2416 }
2417 break;
2418 }
2419 #endif
2420
2421 #ifdef SUPPORT_I18N
2422 /* If it supports internationalised messages, and this meesage need that,
2423 request it */
2424
2425 if ( sx->peer_offered & OPTION_UTF8
2426 && addrlist->prop.utf8_msg
2427 && !addrlist->prop.utf8_downcvt
2428 )
2429 Ustrcpy(p, " SMTPUTF8"), p += 9;
2430 #endif
2431
2432 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS)
2433 if (tls_requiretls & REQUIRETLS_MSG)
2434 Ustrcpy(p, " REQUIRETLS") , p += 11;
2435 #endif
2436
2437 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
2438 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
2439 addr && address_count < sx->max_rcpt;
2440 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2441 {
2442 address_count++;
2443 if (!(addr->dsn_flags & rf_dsnlasthop))
2444 {
2445 sx->dsn_all_lasthop = FALSE;
2446 break;
2447 }
2448 }
2449
2450 /* Add any DSN flags to the mail command */
2451
2452 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
2453 {
2454 if (dsn_ret == dsn_ret_hdrs)
2455 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2456 else if (dsn_ret == dsn_ret_full)
2457 { Ustrcpy(p, " RET=FULL"); p += 9; }
2458
2459 if (dsn_envid)
2460 {
2461 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
2462 while (*p) p++;
2463 }
2464 }
2465
2466 /* If an authenticated_sender override has been specified for this transport
2467 instance, expand it. If the expansion is forced to fail, and there was already
2468 an authenticated_sender for this message, the original value will be used.
2469 Other expansion failures are serious. An empty result is ignored, but there is
2470 otherwise no check - this feature is expected to be used with LMTP and other
2471 cases where non-standard addresses (e.g. without domains) might be required. */
2472
2473 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->ob))
2474 return ERROR;
2475
2476 return OK;
2477 }
2478
2479
2480 static void
2481 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
2482 {
2483 uschar * p = sx->buffer;
2484 *p = 0;
2485
2486 /* Add any DSN flags to the rcpt command */
2487
2488 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2489 {
2490 if (addr->dsn_flags & rf_dsnflags)
2491 {
2492 int i;
2493 BOOL first = TRUE;
2494
2495 Ustrcpy(p, " NOTIFY=");
2496 while (*p) p++;
2497 for (i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
2498 {
2499 if (!first) *p++ = ',';
2500 first = FALSE;
2501 Ustrcpy(p, rf_names[i]);
2502 while (*p) p++;
2503 }
2504 }
2505
2506 if (addr->dsn_orcpt)
2507 {
2508 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
2509 addr->dsn_orcpt);
2510 while (*p) p++;
2511 }
2512 }
2513 }
2514
2515
2516
2517 /*
2518 Return:
2519 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
2520 -1 MAIL response error
2521 -2 any non-MAIL read i/o error
2522 -3 non-MAIL response timeout
2523 -4 internal error; channel still usable
2524 -5 transmit failed
2525 */
2526
2527 int
2528 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
2529 {
2530 address_item * addr;
2531 int address_count;
2532 int rc;
2533
2534 if (build_mailcmd_options(sx, sx->first_addr) != OK)
2535 {
2536 *yield = ERROR;
2537 return -4;
2538 }
2539
2540 /* From here until we send the DATA command, we can make use of PIPELINING
2541 if the server host supports it. The code has to be able to check the responses
2542 at any point, for when the buffer fills up, so we write it totally generally.
2543 When PIPELINING is off, each command written reports that it has flushed the
2544 buffer. */
2545
2546 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
2547
2548 {
2549 uschar * s = sx->from_addr;
2550 #ifdef SUPPORT_I18N
2551 uschar * errstr = NULL;
2552
2553 /* If we must downconvert, do the from-address here. Remember we had to
2554 for the to-addresses (done below), and also (ugly) for re-doing when building
2555 the delivery log line. */
2556
2557 if ( sx->addrlist->prop.utf8_msg
2558 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
2559 )
2560 {
2561 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
2562 {
2563 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2564 *yield = ERROR;
2565 return -4;
2566 }
2567 setflag(sx->addrlist, af_utf8_downcvt);
2568 }
2569 #endif
2570
2571 rc = smtp_write_command(&sx->outblock, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
2572 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
2573 }
2574
2575 mail_command = string_copy(big_buffer); /* Save for later error message */
2576
2577 switch(rc)
2578 {
2579 case -1: /* Transmission error */
2580 return -5;
2581
2582 case +1: /* Cmd was sent */
2583 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
2584 sx->ob->command_timeout))
2585 {
2586 if (errno == 0 && sx->buffer[0] == '4')
2587 {
2588 errno = ERRNO_MAIL4XX;
2589 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2590 }
2591 return -1;
2592 }
2593 sx->pending_MAIL = FALSE;
2594 break;
2595
2596 /* otherwise zero: command queued for pipeline */
2597 }
2598
2599 /* Pass over all the relevant recipient addresses for this host, which are the
2600 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2601 several before we have to read the responses for those seen so far. This
2602 checking is done by a subroutine because it also needs to be done at the end.
2603 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
2604 the next one if not all are sent.
2605
2606 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2607 last address because we want to abort if any recipients have any kind of
2608 problem, temporary or permanent. We know that all recipient addresses will have
2609 the PENDING_DEFER status, because only one attempt is ever made, and we know
2610 that max_rcpt will be large, so all addresses will be done at once.
2611
2612 For verify we flush the pipeline after any (the only) rcpt address. */
2613
2614 for (addr = sx->first_addr, address_count = 0;
2615 addr && address_count < sx->max_rcpt;
2616 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2617 {
2618 int count;
2619 BOOL no_flush;
2620 uschar * rcpt_addr;
2621
2622 if (tcp_out_fastopen && !tcp_out_fastopen_logged)
2623 {
2624 setflag(addr, af_tcp_fastopen_conn);
2625 if (tcp_out_fastopen > 1) setflag(addr, af_tcp_fastopen);
2626 }
2627
2628 addr->dsn_aware = sx->peer_offered & OPTION_DSN
2629 ? dsn_support_yes : dsn_support_no;
2630
2631 address_count++;
2632 no_flush = pipelining_active && !sx->verify
2633 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
2634
2635 build_rcptcmd_options(sx, addr);
2636
2637 /* Now send the RCPT command, and process outstanding responses when
2638 necessary. After a timeout on RCPT, we just end the function, leaving the
2639 yield as OK, because this error can often mean that there is a problem with
2640 just one address, so we don't want to delay the host. */
2641
2642 rcpt_addr = transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes);
2643
2644 #ifdef SUPPORT_I18N
2645 if ( testflag(sx->addrlist, af_utf8_downcvt)
2646 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
2647 )
2648 {
2649 /*XXX could we use a per-address errstr here? Not fail the whole send? */
2650 errno = ERRNO_EXPANDFAIL;
2651 return -5; /*XXX too harsh? */
2652 }
2653 #endif
2654
2655 count = smtp_write_command(&sx->outblock, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
2656 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
2657
2658 if (count < 0) return -5;
2659 if (count > 0)
2660 {
2661 switch(sync_responses(sx, count, 0))
2662 {
2663 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
2664 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2665 break;
2666
2667 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2668 if (!sx->lmtp) /* can't tell about progress yet */
2669 sx->completed_addr = TRUE;
2670 case 0: /* No 2xx or 5xx, but no probs */
2671 break;
2672
2673 case -1: return -3; /* Timeout on RCPT */
2674 case -2: return -2; /* non-MAIL read i/o error */
2675 default: return -1; /* any MAIL error */
2676 }
2677 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
2678 }
2679 } /* Loop for next address */
2680
2681 tcp_out_fastopen_logged = TRUE;
2682 sx->next_addr = addr;
2683 return 0;
2684 }
2685
2686
2687 #ifdef SUPPORT_TLS
2688 /*****************************************************
2689 * Proxy TLS connection for another transport process *
2690 ******************************************************/
2691 /*
2692 Close the unused end of the pipe, fork once more, then use the given buffer
2693 as a staging area, and select on both the given fd and the TLS'd client-fd for
2694 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
2695 Do blocking full-size writes, and reads under a timeout. Once both input
2696 channels are closed, exit the process.
2697
2698 Arguments:
2699 ct_ctx tls context
2700 buf space to use for buffering
2701 bufsiz size of buffer
2702 pfd pipe filedescriptor array; [0] is comms to proxied process
2703 timeout per-read timeout, seconds
2704 */
2705
2706 void
2707 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
2708 int timeout)
2709 {
2710 fd_set rfds, efds;
2711 int max_fd = MAX(pfd[0], tls_out.active.sock) + 1;
2712 int rc, i, fd_bits, nbytes;
2713
2714 close(pfd[1]);
2715 if ((rc = fork()))
2716 {
2717 DEBUG(D_transport) debug_printf("proxy-proc final-pid %d\n", rc);
2718 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
2719 }
2720
2721 if (running_in_test_harness) millisleep(100); /* let parent debug out */
2722 set_process_info("proxying TLS connection for continued transport");
2723 FD_ZERO(&rfds);
2724 FD_SET(tls_out.active.sock, &rfds);
2725 FD_SET(pfd[0], &rfds);
2726
2727 for (fd_bits = 3; fd_bits; )
2728 {
2729 time_t time_left = timeout;
2730 time_t time_start = time(NULL);
2731
2732 /* wait for data */
2733 efds = rfds;
2734 do
2735 {
2736 struct timeval tv = { time_left, 0 };
2737
2738 rc = select(max_fd,
2739 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
2740
2741 if (rc < 0 && errno == EINTR)
2742 if ((time_left -= time(NULL) - time_start) > 0) continue;
2743
2744 if (rc <= 0)
2745 {
2746 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
2747 goto done;
2748 }
2749
2750 if (FD_ISSET(tls_out.active.sock, &efds) || FD_ISSET(pfd[0], &efds))
2751 {
2752 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
2753 FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
2754 goto done;
2755 }
2756 }
2757 while (rc < 0 || !(FD_ISSET(tls_out.active.sock, &rfds) || FD_ISSET(pfd[0], &rfds)));
2758
2759 /* handle inbound data */
2760 if (FD_ISSET(tls_out.active.sock, &rfds))
2761 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0)
2762 {
2763 fd_bits &= ~1;
2764 FD_CLR(tls_out.active.sock, &rfds);
2765 shutdown(pfd[0], SHUT_WR);
2766 timeout = 5;
2767 }
2768 else
2769 {
2770 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2771 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
2772 }
2773 else if (fd_bits & 1)
2774 FD_SET(tls_out.active.sock, &rfds);
2775
2776 /* handle outbound data */
2777 if (FD_ISSET(pfd[0], &rfds))
2778 if ((rc = read(pfd[0], buf, bsize)) <= 0)
2779 {
2780 fd_bits = 0;
2781 tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
2782 ct_ctx = NULL;
2783 }
2784 else
2785 {
2786 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2787 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
2788 goto done;
2789 }
2790 else if (fd_bits & 2)
2791 FD_SET(pfd[0], &rfds);
2792 }
2793
2794 done:
2795 if (running_in_test_harness) millisleep(100); /* let logging complete */
2796 exim_exit(0, US"TLS proxy");
2797 }
2798 #endif
2799
2800
2801 /*************************************************
2802 * Deliver address list to given host *
2803 *************************************************/
2804
2805 /* If continue_hostname is not null, we get here only when continuing to
2806 deliver down an existing channel. The channel was passed as the standard
2807 input. TLS is never active on a passed channel; the previous process always
2808 closes it down before passing the connection on.
2809
2810 Otherwise, we have to make a connection to the remote host, and do the
2811 initial protocol exchange.
2812
2813 When running as an MUA wrapper, if the sender or any recipient is rejected,
2814 temporarily or permanently, we force failure for all recipients.
2815
2816 Arguments:
2817 addrlist chain of potential addresses to deliver; only those whose
2818 transport_return field is set to PENDING_DEFER are currently
2819 being processed; others should be skipped - they have either
2820 been delivered to an earlier host or IP address, or been
2821 failed by one of them.
2822 host host to deliver to
2823 host_af AF_INET or AF_INET6
2824 defport default TCP/IP port to use if host does not specify, in host
2825 byte order
2826 interface interface to bind to, or NULL
2827 tblock transport instance block
2828 message_defer set TRUE if yield is OK, but all addresses were deferred
2829 because of a non-recipient, non-host failure, that is, a
2830 4xx response to MAIL FROM, DATA, or ".". This is a defer
2831 that is specific to the message.
2832 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2833 a second attempt after TLS initialization fails
2834
2835 Returns: OK - the connection was made and the delivery attempted;
2836 the result for each address is in its data block.
2837 DEFER - the connection could not be made, or something failed
2838 while setting up the SMTP session, or there was a
2839 non-message-specific error, such as a timeout.
2840 ERROR - a filter command is specified for this transport,
2841 and there was a problem setting it up; OR helo_data
2842 or add_headers or authenticated_sender is specified
2843 for this transport, and the string failed to expand
2844 */
2845
2846 static int
2847 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
2848 uschar *interface, transport_instance *tblock,
2849 BOOL *message_defer, BOOL suppress_tls)
2850 {
2851 address_item *addr;
2852 int yield = OK;
2853 int save_errno;
2854 int rc;
2855 struct timeval start_delivery_time;
2856
2857 BOOL pass_message = FALSE;
2858 uschar *message = NULL;
2859 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
2860
2861 smtp_context sx;
2862
2863 gettimeofday(&start_delivery_time, NULL);
2864 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
2865 *message_defer = FALSE;
2866
2867 sx.addrlist = addrlist;
2868 sx.host = host;
2869 sx.host_af = host_af,
2870 sx.port = defport;
2871 sx.interface = interface;
2872 sx.helo_data = NULL;
2873 sx.tblock = tblock;
2874 sx.verify = FALSE;
2875
2876 /* Get the channel set up ready for a message (MAIL FROM being the next
2877 SMTP command to send */
2878
2879 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
2880 return rc;
2881
2882 /* If there is a filter command specified for this transport, we can now
2883 set it up. This cannot be done until the identify of the host is known. */
2884
2885 if (tblock->filter_command)
2886 {
2887 transport_filter_timeout = tblock->filter_timeout;
2888
2889 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2890 yield ERROR. */
2891
2892 if (!transport_set_up_command(&transport_filter_argv,
2893 tblock->filter_command, TRUE, DEFER, addrlist,
2894 string_sprintf("%.50s transport", tblock->name), NULL))
2895 {
2896 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2897 FALSE);
2898 yield = ERROR;
2899 goto SEND_QUIT;
2900 }
2901
2902 if ( transport_filter_argv
2903 && *transport_filter_argv
2904 && **transport_filter_argv
2905 && sx.peer_offered & OPTION_CHUNKING
2906 )
2907 {
2908 sx.peer_offered &= ~OPTION_CHUNKING;
2909 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2910 }
2911 }
2912
2913 sx.first_addr = addrlist;
2914
2915 /* For messages that have more than the maximum number of envelope recipients,
2916 we want to send several transactions down the same SMTP connection. (See
2917 comments in deliver.c as to how this reconciles, heuristically, with
2918 remote_max_parallel.) This optimization was added to Exim after the following
2919 code was already working. The simplest way to put it in without disturbing the
2920 code was to use a goto to jump back to this point when there is another
2921 transaction to handle. */
2922
2923 SEND_MESSAGE:
2924 sx.from_addr = return_path;
2925 sx.sync_addr = sx.first_addr;
2926 sx.ok = FALSE;
2927 sx.send_rset = TRUE;
2928 sx.completed_addr = FALSE;
2929
2930
2931 /* If we are a continued-connection-after-verify the MAIL and RCPT
2932 commands were already sent; do not re-send but do mark the addrs as
2933 having been accepted up to RCPT stage. A traditional cont-conn
2934 always has a sequence number greater than one. */
2935
2936 if (continue_hostname && continue_sequence == 1)
2937 {
2938 address_item * addr;
2939
2940 sx.peer_offered = smtp_peer_options;
2941 sx.pending_MAIL = FALSE;
2942 sx.ok = TRUE;
2943 sx.next_addr = NULL;
2944
2945 for (addr = addrlist; addr; addr = addr->next)
2946 addr->transport_return = PENDING_OK;
2947 }
2948 else
2949 {
2950 /* Initiate a message transfer. */
2951
2952 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
2953 {
2954 case 0: break;
2955 case -1: case -2: goto RESPONSE_FAILED;
2956 case -3: goto END_OFF;
2957 case -4: goto SEND_QUIT;
2958 default: goto SEND_FAILED;
2959 }
2960
2961 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2962 permanently or temporarily. We should have flushed and synced after the last
2963 RCPT. */
2964
2965 if (mua_wrapper)
2966 {
2967 address_item * a;
2968 unsigned cnt;
2969
2970 for (a = sx.first_addr, cnt = 0; a && cnt < sx.max_rcpt; a = a->next, cnt++)
2971 if (a->transport_return != PENDING_OK)
2972 {
2973 /*XXX could we find a better errno than 0 here? */
2974 set_errno_nohost(addrlist, 0, a->message, FAIL,
2975 testflag(a, af_pass_message));
2976 sx.ok = FALSE;
2977 break;
2978 }
2979 }
2980 }
2981
2982 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2983 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2984 have a good recipient buffered up if we are pipelining. We don't want to waste
2985 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2986 are pipelining. The responses are all handled by sync_responses().
2987 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2988 to send is. */
2989
2990 if ( !(sx.peer_offered & OPTION_CHUNKING)
2991 && (sx.ok || (pipelining_active && !mua_wrapper)))
2992 {
2993 int count = smtp_write_command(&sx.outblock, SCMD_FLUSH, "DATA\r\n");
2994
2995 if (count < 0) goto SEND_FAILED;
2996 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
2997 {
2998 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2999 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3000 break;
3001
3002 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3003 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3004 case 0: break; /* No 2xx or 5xx, but no probs */
3005
3006 case -1: goto END_OFF; /* Timeout on RCPT */
3007 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3008 }
3009 pipelining_active = FALSE;
3010 data_command = string_copy(big_buffer); /* Save for later error message */
3011 }
3012
3013 /* If there were no good recipients (but otherwise there have been no
3014 problems), just set ok TRUE, since we have handled address-specific errors
3015 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3016 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3017 well as body. Set the appropriate timeout value to be used for each chunk.
3018 (Haven't been able to make it work using select() for writing yet.) */
3019
3020 if (!(sx.peer_offered & OPTION_CHUNKING) && !sx.ok)
3021 {
3022 /* Save the first address of the next batch. */
3023 sx.first_addr = sx.next_addr;
3024
3025 sx.ok = TRUE;
3026 }
3027 else
3028 {
3029 transport_ctx tctx = {
3030 {sx.cctx.sock}, /*XXX will this need TLS info? */
3031 tblock,
3032 addrlist,
3033 US".", US"..", /* Escaping strings */
3034 topt_use_crlf | topt_escape_headers
3035 | (tblock->body_only ? topt_no_headers : 0)
3036 | (tblock->headers_only ? topt_no_body : 0)
3037 | (tblock->return_path_add ? topt_add_return_path : 0)
3038 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3039 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3040 };
3041
3042 /* If using CHUNKING we need a callback from the generic transport
3043 support to us, for the sending of BDAT smtp commands and the reaping
3044 of responses. The callback needs a whole bunch of state so set up
3045 a transport-context structure to be passed around. */
3046
3047 if (sx.peer_offered & OPTION_CHUNKING)
3048 {
3049 tctx.check_string = tctx.escape_string = NULL;
3050 tctx.options |= topt_use_bdat;
3051 tctx.chunk_cb = smtp_chunk_cmd_callback;
3052 sx.pending_BDAT = FALSE;
3053 sx.good_RCPT = sx.ok;
3054 sx.cmd_count = 0;
3055 tctx.smtp_context = &sx;
3056 }
3057 else
3058 tctx.options |= topt_end_dot;
3059
3060 /* Save the first address of the next batch. */
3061 sx.first_addr = sx.next_addr;
3062
3063 /* Responses from CHUNKING commands go in buffer. Otherwise,
3064 there has not been a response. */
3065
3066 sx.buffer[0] = 0;
3067
3068 sigalrm_seen = FALSE;
3069 transport_write_timeout = sx.ob->data_timeout;
3070 smtp_command = US"sending data block"; /* For error messages */
3071 DEBUG(D_transport|D_v)
3072 if (sx.peer_offered & OPTION_CHUNKING)
3073 debug_printf(" will write message using CHUNKING\n");
3074 else
3075 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3076 transport_count = 0;
3077
3078 #ifndef DISABLE_DKIM
3079 dkim_exim_sign_init();
3080 # ifdef EXPERIMENTAL_ARC
3081 {
3082 uschar * s = sx.ob->arc_sign;
3083 if (s)
3084 {
3085 if (!(sx.ob->dkim.arc_signspec = s = expand_string(s)))
3086 {
3087 if (!expand_string_forcedfail)
3088 {
3089 message = US"failed to expand arc_sign";
3090 sx.ok = FALSE;
3091 goto SEND_FAILED;
3092 }
3093 }
3094 else if (*s)
3095 {
3096 /* Ask dkim code to hash the body for ARC */
3097 (void) arc_ams_setup_sign_bodyhash();
3098 sx.ob->dkim.force_bodyhash = TRUE;
3099 }
3100 }
3101 }
3102 # endif
3103 sx.ok = dkim_transport_write_message(&tctx, &sx.ob->dkim, CUSS &message);
3104 #else
3105 sx.ok = transport_write_message(&tctx, 0);
3106 #endif
3107
3108 /* transport_write_message() uses write() because it is called from other
3109 places to write to non-sockets. This means that under some OS (e.g. Solaris)
3110 it can exit with "Broken pipe" as its error. This really means that the
3111 socket got closed at the far end. */
3112
3113 transport_write_timeout = 0; /* for subsequent transports */
3114
3115 /* Failure can either be some kind of I/O disaster (including timeout),
3116 or the failure of a transport filter or the expansion of added headers.
3117 Or, when CHUNKING, it can be a protocol-detected failure. */
3118
3119 if (!sx.ok)
3120 if (message) goto SEND_FAILED;
3121 else goto RESPONSE_FAILED;
3122
3123 /* We used to send the terminating "." explicitly here, but because of
3124 buffering effects at both ends of TCP/IP connections, you don't gain
3125 anything by keeping it separate, so it might as well go in the final
3126 data buffer for efficiency. This is now done by setting the topt_end_dot
3127 flag above. */
3128
3129 smtp_command = US"end of data";
3130
3131 if (sx.peer_offered & OPTION_CHUNKING && sx.cmd_count > 1)
3132 {
3133 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
3134 switch(sync_responses(&sx, sx.cmd_count-1, 0))
3135 {
3136 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3137 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3138 break;
3139
3140 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3141 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3142 case 0: break; /* No 2xx or 5xx, but no probs */
3143
3144 case -1: goto END_OFF; /* Timeout on RCPT */
3145 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3146 }
3147 }
3148
3149 #ifndef DISABLE_PRDR
3150 /* For PRDR we optionally get a partial-responses warning
3151 * followed by the individual responses, before going on with
3152 * the overall response. If we don't get the warning then deal
3153 * with per non-PRDR. */
3154 if(sx.prdr_active)
3155 {
3156 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '3',
3157 sx.ob->final_timeout);
3158 if (!sx.ok && errno == 0) switch(sx.buffer[0])
3159 {
3160 case '2': sx.prdr_active = FALSE;
3161 sx.ok = TRUE;
3162 break;
3163 case '4': errno = ERRNO_DATA4XX;
3164 addrlist->more_errno |=
3165 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3166 break;
3167 }
3168 }
3169 else
3170 #endif
3171
3172 /* For non-PRDR SMTP, we now read a single response that applies to the
3173 whole message. If it is OK, then all the addresses have been delivered. */
3174
3175 if (!sx.lmtp)
3176 {
3177 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3178 sx.ob->final_timeout);
3179 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
3180 {
3181 errno = ERRNO_DATA4XX;
3182 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3183 }
3184 }
3185
3186 /* For LMTP, we get back a response for every RCPT command that we sent;
3187 some may be accepted and some rejected. For those that get a response, their
3188 status is fixed; any that are accepted have been handed over, even if later
3189 responses crash - at least, that's how I read RFC 2033.
3190
3191 If all went well, mark the recipient addresses as completed, record which
3192 host/IPaddress they were delivered to, and cut out RSET when sending another
3193 message down the same channel. Write the completed addresses to the journal
3194 now so that they are recorded in case there is a crash of hardware or
3195 software before the spool gets updated. Also record the final SMTP
3196 confirmation if needed (for SMTP only). */
3197
3198 if (sx.ok)
3199 {
3200 int flag = '=';
3201 struct timeval delivery_time;
3202 int len;
3203 uschar * conf = NULL;
3204
3205 timesince(&delivery_time, &start_delivery_time);
3206 sx.send_rset = FALSE;
3207 pipelining_active = FALSE;
3208
3209 /* Set up confirmation if needed - applies only to SMTP */
3210
3211 if (
3212 #ifdef DISABLE_EVENT
3213 LOGGING(smtp_confirmation) &&
3214 #endif
3215 !sx.lmtp
3216 )
3217 {
3218 const uschar *s = string_printing(sx.buffer);
3219 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3220 conf = (s == sx.buffer)? US string_copy(s) : US s;
3221 }
3222
3223 /* Process all transported addresses - for LMTP or PRDR, read a status for
3224 each one. */
3225
3226 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3227 {
3228 if (addr->transport_return != PENDING_OK) continue;
3229
3230 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3231 remaining addresses. Otherwise, it's a return code for just the one
3232 address. For temporary errors, add a retry item for the address so that
3233 it doesn't get tried again too soon. */
3234
3235 #ifndef DISABLE_PRDR
3236 if (sx.lmtp || sx.prdr_active)
3237 #else
3238 if (sx.lmtp)
3239 #endif
3240 {
3241 if (!smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3242 sx.ob->final_timeout))
3243 {
3244 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3245 addr->message = string_sprintf(
3246 #ifndef DISABLE_PRDR
3247 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3248 #else
3249 "LMTP error after %s: %s",
3250 #endif
3251 data_command, string_printing(sx.buffer));
3252 setflag(addr, af_pass_message); /* Allow message to go to user */
3253 if (sx.buffer[0] == '5')
3254 addr->transport_return = FAIL;
3255 else
3256 {
3257 errno = ERRNO_DATA4XX;
3258 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3259 addr->transport_return = DEFER;
3260 #ifndef DISABLE_PRDR
3261 if (!sx.prdr_active)
3262 #endif
3263 retry_add_item(addr, addr->address_retry_key, 0);
3264 }
3265 continue;
3266 }
3267 sx.completed_addr = TRUE; /* NOW we can set this flag */
3268 if (LOGGING(smtp_confirmation))
3269 {
3270 const uschar *s = string_printing(sx.buffer);
3271 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3272 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3273 }
3274 }
3275
3276 /* SMTP, or success return from LMTP for this address. Pass back the
3277 actual host that was used. */
3278
3279 addr->transport_return = OK;
3280 addr->more_errno = delivery_time.tv_sec;
3281 addr->delivery_usec = delivery_time.tv_usec;
3282 addr->host_used = host;
3283 addr->special_action = flag;
3284 addr->message = conf;
3285 #ifndef DISABLE_PRDR
3286 if (sx.prdr_active) setflag(addr, af_prdr_used);
3287 #endif
3288 if (sx.peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
3289 flag = '-';
3290
3291 #ifndef DISABLE_PRDR
3292 if (!sx.prdr_active)
3293 #endif
3294 {
3295 /* Update the journal. For homonymic addresses, use the base address plus
3296 the transport name. See lots of comments in deliver.c about the reasons
3297 for the complications when homonyms are involved. Just carry on after
3298 write error, as it may prove possible to update the spool file later. */
3299
3300 if (testflag(addr, af_homonym))
3301 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3302 else
3303 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3304
3305 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3306 len = Ustrlen(CS sx.buffer);
3307 if (write(journal_fd, sx.buffer, len) != len)
3308 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3309 "%s: %s", sx.buffer, strerror(errno));
3310 }
3311 }
3312
3313 #ifndef DISABLE_PRDR
3314 if (sx.prdr_active)
3315 {
3316 const uschar * overall_message;
3317
3318 /* PRDR - get the final, overall response. For any non-success
3319 upgrade all the address statuses. */
3320
3321 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3322 sx.ob->final_timeout);
3323 if (!sx.ok)
3324 {
3325 if(errno == 0 && sx.buffer[0] == '4')
3326 {
3327 errno = ERRNO_DATA4XX;
3328 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3329 }
3330 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3331 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3332 addr->transport_return = PENDING_OK; /* allow set_errno action */
3333 goto RESPONSE_FAILED;
3334 }
3335
3336 /* Append the overall response to the individual PRDR response for logging
3337 and update the journal, or setup retry. */
3338
3339 overall_message = string_printing(sx.buffer);
3340 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3341 if (addr->transport_return == OK)
3342 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
3343
3344 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3345 if (addr->transport_return == OK)
3346 {
3347 if (testflag(addr, af_homonym))
3348 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3349 else
3350 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3351
3352 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3353 len = Ustrlen(CS sx.buffer);
3354 if (write(journal_fd, sx.buffer, len) != len)
3355 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3356 "%s: %s", sx.buffer, strerror(errno));
3357 }
3358 else if (addr->transport_return == DEFER)
3359 retry_add_item(addr, addr->address_retry_key, -2);
3360 }
3361 #endif
3362
3363 /* Ensure the journal file is pushed out to disk. */
3364
3365 if (EXIMfsync(journal_fd) < 0)
3366 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3367 strerror(errno));
3368 }
3369 }
3370
3371
3372 /* Handle general (not specific to one address) failures here. The value of ok
3373 is used to skip over this code on the falling through case. A timeout causes a
3374 deferral. Other errors may defer or fail according to the response code, and
3375 may set up a special errno value, e.g. after connection chopped, which is
3376 assumed if errno == 0 and there is no text in the buffer. If control reaches
3377 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3378 the problem is not related to this specific message. */
3379
3380 if (!sx.ok)
3381 {
3382 int code, set_rc;
3383 uschar * set_message;
3384
3385 RESPONSE_FAILED:
3386 {
3387 save_errno = errno;
3388 message = NULL;
3389 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3390 sx.buffer, &code, &message, &pass_message);
3391 goto FAILED;
3392 }
3393
3394 SEND_FAILED:
3395 {
3396 save_errno = errno;
3397 code = '4';
3398 message = string_sprintf("send() to %s [%s] failed: %s",
3399 host->name, host->address, message ? message : US strerror(save_errno));
3400 sx.send_quit = FALSE;
3401 goto FAILED;
3402 }
3403
3404 FAILED:
3405 {
3406 BOOL message_error;
3407
3408 sx.ok = FALSE; /* For when reached by GOTO */
3409 set_message = message;
3410
3411 /* We want to handle timeouts after MAIL or "." and loss of connection after
3412 "." specially. They can indicate a problem with the sender address or with
3413 the contents of the message rather than a real error on the connection. These
3414 cases are treated in the same way as a 4xx response. This next bit of code
3415 does the classification. */
3416
3417 switch(save_errno)
3418 {
3419 case 0:
3420 case ERRNO_MAIL4XX:
3421 case ERRNO_DATA4XX:
3422 message_error = TRUE;
3423 break;
3424
3425 case ETIMEDOUT:
3426 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
3427 Ustrncmp(smtp_command,"end ",4) == 0;
3428 break;
3429
3430 case ERRNO_SMTPCLOSED:
3431 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
3432 break;
3433
3434 default:
3435 message_error = FALSE;
3436 break;
3437 }
3438
3439 /* Handle the cases that are treated as message errors. These are:
3440
3441 (a) negative response or timeout after MAIL
3442 (b) negative response after DATA
3443 (c) negative response or timeout or dropped connection after "."
3444 (d) utf8 support required and not offered
3445
3446 It won't be a negative response or timeout after RCPT, as that is dealt
3447 with separately above. The action in all cases is to set an appropriate
3448 error code for all the addresses, but to leave yield set to OK because the
3449 host itself has not failed. Of course, it might in practice have failed
3450 when we've had a timeout, but if so, we'll discover that at the next
3451 delivery attempt. For a temporary error, set the message_defer flag, and
3452 write to the logs for information if this is not the last host. The error
3453 for the last host will be logged as part of the address's log line. */
3454
3455 if (message_error)
3456 {
3457 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
3458
3459 /* If there's an errno, the message contains just the identity of
3460 the host. */
3461
3462 if (code == '5')
3463 set_rc = FAIL;
3464 else /* Anything other than 5 is treated as temporary */
3465 {
3466 set_rc = DEFER;
3467 if (save_errno > 0)
3468 message = US string_sprintf("%s: %s", message, strerror(save_errno));
3469
3470 write_logs(host, message, sx.first_addr ? sx.first_addr->basic_errno : 0);
3471
3472 *message_defer = TRUE;
3473 }
3474 }
3475
3476 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
3477 ".", or some other transportation error. We defer all addresses and yield
3478 DEFER, except for the case of failed add_headers expansion, or a transport
3479 filter failure, when the yield should be ERROR, to stop it trying other
3480 hosts. */
3481
3482 else
3483 {
3484 set_rc = DEFER;
3485 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
3486 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3487 }
3488 }
3489
3490 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3491 #ifdef EXPERIMENTAL_DSN_INFO
3492 , sx.smtp_greeting, sx.helo_response
3493 #endif
3494 );
3495 }
3496
3497
3498 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3499 SMTP session tidily. However, if there were too many addresses to send in one
3500 message (indicated by first_addr being non-NULL) we want to carry on with the
3501 rest of them. Also, it is desirable to send more than one message down the SMTP
3502 connection if there are several waiting, provided we haven't already sent so
3503 many as to hit the configured limit. The function transport_check_waiting looks
3504 for a waiting message and returns its id. Then transport_pass_socket tries to
3505 set up a continued delivery by passing the socket on to another process. The
3506 variable send_rset is FALSE if a message has just been successfully transfered.
3507
3508 If we are already sending down a continued channel, there may be further
3509 addresses not yet delivered that are aimed at the same host, but which have not
3510 been passed in this run of the transport. In this case, continue_more will be
3511 true, and all we should do is send RSET if necessary, and return, leaving the
3512 channel open.
3513
3514 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3515 do not want to continue with other messages down the same channel, because that
3516 can lead to looping between two or more messages, all with the same,
3517 temporarily failing address(es). [The retry information isn't updated yet, so
3518 new processes keep on trying.] We probably also don't want to try more of this
3519 message's addresses either.
3520
3521 If we have started a TLS session, we have to end it before passing the
3522 connection to a new process. However, not all servers can handle this (Exim
3523 can), so we do not pass such a connection on if the host matches
3524 hosts_nopass_tls. */
3525
3526 DEBUG(D_transport)
3527 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3528 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
3529 sx.send_rset, continue_more, yield, sx.first_addr ? "not " : "");
3530
3531 if (sx.completed_addr && sx.ok && sx.send_quit)
3532 {
3533 BOOL more;
3534 smtp_compare_t t_compare;
3535
3536 t_compare.tblock = tblock;
3537 t_compare.current_sender_address = sender_address;
3538
3539 if ( sx.first_addr != NULL
3540 || continue_more
3541 || (
3542 #ifdef SUPPORT_TLS
3543 ( tls_out.active.sock < 0 && !continue_proxy_cipher
3544 || verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
3545 )
3546 &&
3547 #endif
3548 transport_check_waiting(tblock->name, host->name,
3549 tblock->connection_max_messages, new_message_id, &more,
3550 (oicf)smtp_are_same_identities, (void*)&t_compare)
3551 ) )
3552 {
3553 uschar *msg;
3554 BOOL pass_message;
3555
3556 if (sx.send_rset)
3557 if (! (sx.ok = smtp_write_command(&sx.outblock, SCMD_FLUSH, "RSET\r\n") >= 0))
3558 {
3559 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3560 host->address, strerror(errno));
3561 sx.send_quit = FALSE;
3562 }
3563 else if (! (sx.ok = smtp_read_response(&sx.inblock, sx.buffer,
3564 sizeof(sx.buffer), '2', sx.ob->command_timeout)))
3565 {
3566 int code;
3567 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
3568 &pass_message);
3569 if (!sx.send_quit)
3570 {
3571 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3572 host->name, host->address, msg);
3573 }
3574 }
3575
3576 /* Either RSET was not needed, or it succeeded */
3577
3578 if (sx.ok)
3579 {
3580 int pfd[2];
3581 int socket_fd = sx.cctx.sock;
3582
3583
3584 if (sx.first_addr != NULL) /* More addresses still to be sent */
3585 { /* in this run of the transport */
3586 continue_sequence++; /* Causes * in logging */
3587 goto SEND_MESSAGE;
3588 }
3589
3590 /* Unless caller said it already has more messages listed for this host,
3591 pass the connection on to a new Exim process (below, the call to
3592 transport_pass_socket). If the caller has more ready, just return with
3593 the connection still open. */
3594
3595 #ifdef SUPPORT_TLS
3596 if (tls_out.active.sock >= 0)
3597 if ( continue_more
3598 || verify_check_given_host(&sx.ob->hosts_noproxy_tls, host) == OK)
3599 {
3600 /* Before passing the socket on, or returning to caller with it still
3601 open, we must shut down TLS. Not all MTAs allow for the continuation
3602 of the SMTP session when TLS is shut down. We test for this by sending
3603 a new EHLO. If we don't get a good response, we don't attempt to pass
3604 the socket on. */
3605
3606 tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
3607 sx.cctx.tls_ctx = NULL;
3608 smtp_peer_options = smtp_peer_options_wrap;
3609 sx.ok = !sx.smtps
3610 && smtp_write_command(&sx.outblock, SCMD_FLUSH,
3611 "EHLO %s\r\n", sx.helo_data) >= 0
3612 && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
3613 '2', sx.ob->command_timeout);
3614
3615 if (sx.ok && continue_more)
3616 return yield; /* More addresses for another run */
3617 }
3618 else
3619 {
3620 /* Set up a pipe for proxying TLS for the new transport process */
3621
3622 smtp_peer_options |= OPTION_TLS;
3623 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
3624 socket_fd = pfd[1];
3625 else
3626 set_errno(sx.first_addr, errno, US"internal allocation problem",
3627 DEFER, FALSE, host
3628 # ifdef EXPERIMENTAL_DSN_INFO
3629 , sx.smtp_greeting, sx.helo_response
3630 # endif
3631 );
3632 }
3633 else
3634 #endif
3635 if (continue_more)
3636 return yield; /* More addresses for another run */
3637
3638 /* If the socket is successfully passed, we mustn't send QUIT (or
3639 indeed anything!) from here. */
3640
3641 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3642 propagate it from the initial
3643 */
3644 if (sx.ok && transport_pass_socket(tblock->name, host->name,
3645 host->address, new_message_id, socket_fd))
3646 {
3647 sx.send_quit = FALSE;
3648
3649 /* We have passed the client socket to a fresh transport process.
3650 If TLS is still active, we need to proxy it for the transport we
3651 just passed the baton to. Fork a child to to do it, and return to
3652 get logging done asap. Which way to place the work makes assumptions
3653 about post-fork prioritisation which may not hold on all platforms. */
3654 #ifdef SUPPORT_TLS
3655 if (tls_out.active.sock >= 0)
3656 {
3657 int pid = fork();
3658 if (pid == 0) /* child; fork again to disconnect totally */
3659 {
3660 if (running_in_test_harness) millisleep(100); /* let parent debug out */
3661 /* does not return */
3662 smtp_proxy_tls(sx.cctx.tls_ctx, sx.buffer, sizeof(sx.buffer), pfd,
3663 sx.ob->command_timeout);
3664 }
3665
3666 if (pid > 0) /* parent */
3667 {
3668 DEBUG(D_transport) debug_printf("proxy-proc inter-pid %d\n", pid);
3669 close(pfd[0]);
3670 /* tidy the inter-proc to disconn the proxy proc */
3671 waitpid(pid, NULL, 0);
3672 tls_close(sx.cctx.tls_ctx, TLS_NO_SHUTDOWN);
3673 sx.cctx.tls_ctx = NULL;
3674 (void)close(sx.cctx.sock);
3675 sx.cctx.sock = -1;
3676 continue_transport = NULL;
3677 continue_hostname = NULL;
3678 return yield;
3679 }
3680 log_write(0, LOG_PANIC_DIE, "fork failed");
3681 }
3682 #endif
3683 }
3684 }
3685
3686 /* If RSET failed and there are addresses left, they get deferred. */
3687 else
3688 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
3689 #ifdef EXPERIMENTAL_DSN_INFO
3690 , sx.smtp_greeting, sx.helo_response
3691 #endif
3692 );
3693 }
3694 }
3695
3696 /* End off tidily with QUIT unless the connection has died or the socket has
3697 been passed to another process. There has been discussion on the net about what
3698 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3699 to wait for a response, but on the other hand, there isn't anything one can do
3700 with an error response, other than log it. Exim used to do that. However,
3701 further discussion suggested that it is positively advantageous not to wait for
3702 the response, but to close the session immediately. This is supposed to move
3703 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3704 load from the server. (Hosts that are both servers and clients may not see much
3705 difference, of course.) Further discussion indicated that this was safe to do
3706 on Unix systems which have decent implementations of TCP/IP that leave the
3707 connection around for a while (TIME_WAIT) after the application has gone away.
3708 This enables the response sent by the server to be properly ACKed rather than
3709 timed out, as can happen on broken TCP/IP implementations on other OS.
3710
3711 This change is being made on 31-Jul-98. After over a year of trouble-free
3712 operation, the old commented-out code was removed on 17-Sep-99. */
3713
3714 SEND_QUIT:
3715 if (sx.send_quit) (void)smtp_write_command(&sx.outblock, SCMD_FLUSH, "QUIT\r\n");
3716
3717 END_OFF:
3718
3719 #ifdef SUPPORT_TLS
3720 tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
3721 sx.cctx.tls_ctx = NULL;
3722 #endif
3723
3724 /* Close the socket, and return the appropriate value, first setting
3725 works because the NULL setting is passed back to the calling process, and
3726 remote_max_parallel is forced to 1 when delivering over an existing connection,
3727
3728 If all went well and continue_more is set, we shouldn't actually get here if
3729 there are further addresses, as the return above will be taken. However,
3730 writing RSET might have failed, or there may be other addresses whose hosts are
3731 specified in the transports, and therefore not visible at top level, in which
3732 case continue_more won't get set. */
3733
3734 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3735 if (sx.send_quit)
3736 {
3737 shutdown(sx.cctx.sock, SHUT_WR);
3738 if (fcntl(sx.cctx.sock, F_SETFL, O_NONBLOCK) == 0)
3739 for (rc = 16; read(sx.cctx.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && rc > 0;)
3740 rc--; /* drain socket */
3741 }
3742 (void)close(sx.cctx.sock);
3743
3744 #ifndef DISABLE_EVENT
3745 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3746 #endif
3747
3748 continue_transport = NULL;
3749 continue_hostname = NULL;
3750 return yield;
3751 }
3752
3753
3754
3755
3756 /*************************************************
3757 * Closedown entry point *
3758 *************************************************/
3759
3760 /* This function is called when exim is passed an open smtp channel
3761 from another incarnation, but the message which it has been asked
3762 to deliver no longer exists. The channel is on stdin.
3763
3764 We might do fancy things like looking for another message to send down
3765 the channel, but if the one we sought has gone, it has probably been
3766 delivered by some other process that itself will seek further messages,
3767 so just close down our connection.
3768
3769 Argument: pointer to the transport instance block
3770 Returns: nothing
3771 */
3772
3773 void
3774 smtp_transport_closedown(transport_instance *tblock)
3775 {
3776 smtp_transport_options_block *ob =
3777 (smtp_transport_options_block *)tblock->options_block;
3778 client_conn_ctx cctx;
3779 smtp_inblock inblock;
3780 smtp_outblock outblock;
3781 uschar buffer[256];
3782 uschar inbuffer[4096];
3783 uschar outbuffer[16];
3784
3785 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
3786 cctx.sock = fileno(stdin);
3787 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
3788
3789 inblock.cctx = &cctx;
3790 inblock.buffer = inbuffer;
3791 inblock.buffersize = sizeof(inbuffer);
3792 inblock.ptr = inbuffer;
3793 inblock.ptrend = inbuffer;
3794
3795 outblock.cctx = &cctx;
3796 outblock.buffersize = sizeof(outbuffer);
3797 outblock.buffer = outbuffer;
3798 outblock.ptr = outbuffer;
3799 outblock.cmd_count = 0;
3800 outblock.authenticating = FALSE;
3801
3802 (void)smtp_write_command(&outblock, SCMD_FLUSH, "QUIT\r\n");
3803 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3804 ob->command_timeout);
3805 (void)close(cctx.sock);
3806 }
3807
3808
3809
3810 /*************************************************
3811 * Prepare addresses for delivery *
3812 *************************************************/
3813
3814 /* This function is called to flush out error settings from previous delivery
3815 attempts to other hosts. It also records whether we got here via an MX record
3816 or not in the more_errno field of the address. We are interested only in
3817 addresses that are still marked DEFER - others may have got delivered to a
3818 previously considered IP address. Set their status to PENDING_DEFER to indicate
3819 which ones are relevant this time.
3820
3821 Arguments:
3822 addrlist the list of addresses
3823 host the host we are delivering to
3824
3825 Returns: the first address for this delivery
3826 */
3827
3828 static address_item *
3829 prepare_addresses(address_item *addrlist, host_item *host)
3830 {
3831 address_item *first_addr = NULL;
3832 address_item *addr;
3833 for (addr = addrlist; addr; addr = addr->next)
3834 if (addr->transport_return == DEFER)
3835 {
3836 if (!first_addr) first_addr = addr;
3837 addr->transport_return = PENDING_DEFER;
3838 addr->basic_errno = 0;
3839 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3840 addr->message = NULL;
3841 #ifdef SUPPORT_TLS
3842 addr->cipher = NULL;
3843 addr->ourcert = NULL;
3844 addr->peercert = NULL;
3845 addr->peerdn = NULL;
3846 addr->ocsp = OCSP_NOT_REQ;
3847 #endif
3848 #ifdef EXPERIMENTAL_DSN_INFO
3849 addr->smtp_greeting = NULL;
3850 addr->helo_response = NULL;
3851 #endif
3852 }
3853 return first_addr;
3854 }
3855
3856
3857
3858 /*************************************************
3859 * Main entry point *
3860 *************************************************/
3861
3862 /* See local README for interface details. As this is a remote transport, it is
3863 given a chain of addresses to be delivered in one connection, if possible. It
3864 always returns TRUE, indicating that each address has its own independent
3865 status set, except if there is a setting up problem, in which case it returns
3866 FALSE. */
3867
3868 BOOL
3869 smtp_transport_entry(
3870 transport_instance *tblock, /* data for this instantiation */
3871 address_item *addrlist) /* addresses we are working on */
3872 {
3873 int cutoff_retry;
3874 int defport;
3875 int hosts_defer = 0;
3876 int hosts_fail = 0;
3877 int hosts_looked_up = 0;
3878 int hosts_retry = 0;
3879 int hosts_serial = 0;
3880 int hosts_total = 0;
3881 int total_hosts_tried = 0;
3882 address_item *addr;
3883 BOOL expired = TRUE;
3884 uschar *expanded_hosts = NULL;
3885 uschar *pistring;
3886 uschar *tid = string_sprintf("%s transport", tblock->name);
3887 smtp_transport_options_block *ob =
3888 (smtp_transport_options_block *)(tblock->options_block);
3889 host_item *hostlist = addrlist->host_list;
3890 host_item *host;
3891
3892 DEBUG(D_transport)
3893 {
3894 debug_printf("%s transport entered\n", tblock->name);
3895 for (addr = addrlist; addr; addr = addr->next)
3896 debug_printf(" %s\n", addr->address);
3897 if (hostlist)
3898 {
3899 debug_printf("hostlist:\n");
3900 for (host = hostlist; host; host = host->next)
3901 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
3902 }
3903 if (continue_hostname)
3904 debug_printf("already connected to %s [%s] (on fd %d)\n",
3905 continue_hostname, continue_host_address,
3906 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
3907 }
3908
3909 /* Set the flag requesting that these hosts be added to the waiting
3910 database if the delivery fails temporarily or if we are running with
3911 queue_smtp or a 2-stage queue run. This gets unset for certain
3912 kinds of error, typically those that are specific to the message. */
3913
3914 update_waiting = TRUE;
3915
3916 /* If a host list is not defined for the addresses - they must all have the
3917 same one in order to be passed to a single transport - or if the transport has
3918 a host list with hosts_override set, use the host list supplied with the
3919 transport. It is an error for this not to exist. */
3920
3921 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS)
3922 if (tls_requiretls & REQUIRETLS_MSG)
3923 ob->tls_tempfail_tryclear = FALSE; /*XXX surely we should have a local for this
3924 rather than modifying the transport? */
3925 #endif
3926
3927 if (!hostlist || (ob->hosts_override && ob->hosts))
3928 {
3929 if (!ob->hosts)
3930 {
3931 addrlist->message = string_sprintf("%s transport called with no hosts set",
3932 tblock->name);
3933 addrlist->transport_return = PANIC;
3934 return FALSE; /* Only top address has status */
3935 }
3936
3937 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3938 ob->hosts);
3939
3940 /* If the transport's host list contains no '$' characters, and we are not
3941 randomizing, it is fixed and therefore a chain of hosts can be built once
3942 and for all, and remembered for subsequent use by other calls to this
3943 transport. If, on the other hand, the host list does contain '$', or we are
3944 randomizing its order, we have to rebuild it each time. In the fixed case,
3945 as the hosts string will never be used again, it doesn't matter that we
3946 replace all the : characters with zeros. */
3947
3948 if (!ob->hostlist)
3949 {
3950 uschar *s = ob->hosts;
3951
3952 if (Ustrchr(s, '$') != NULL)
3953 {
3954 if (!(expanded_hosts = expand_string(s)))
3955 {
3956 addrlist->message = string_sprintf("failed to expand list of hosts "
3957 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3958 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3959 return FALSE; /* Only top address has status */
3960 }
3961 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3962 "\"%s\"\n", s, expanded_hosts);
3963 s = expanded_hosts;
3964 }
3965 else
3966 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3967
3968 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3969
3970 /* Check that the expansion yielded something useful. */
3971 if (!hostlist)
3972 {
3973 addrlist->message =
3974 string_sprintf("%s transport has empty hosts setting", tblock->name);
3975 addrlist->transport_return = PANIC;
3976 return FALSE; /* Only top address has status */
3977 }
3978
3979 /* If there was no expansion of hosts, save the host list for
3980 next time. */
3981
3982 if (!expanded_hosts) ob->hostlist = hostlist;
3983 }
3984
3985 /* This is not the first time this transport has been run in this delivery;
3986 the host list was built previously. */
3987
3988 else
3989 hostlist = ob->hostlist;
3990 }
3991
3992 /* The host list was supplied with the address. If hosts_randomize is set, we
3993 must sort it into a random order if it did not come from MX records and has not
3994 already been randomized (but don't bother if continuing down an existing
3995 connection). */
3996
3997 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3998 {
3999 host_item *newlist = NULL;
4000 while (hostlist)
4001 {
4002 host_item *h = hostlist;
4003 hostlist = hostlist->next;
4004
4005 h->sort_key = random_number(100);
4006
4007 if (!newlist)
4008 {
4009 h->next = NULL;
4010 newlist = h;
4011 }
4012 else if (h->sort_key < newlist->sort_key)
4013 {
4014 h->next = newlist;
4015 newlist = h;
4016 }
4017 else
4018 {
4019 host_item *hh = newlist;
4020 while (hh->next)
4021 {
4022 if (h->sort_key < hh->next->sort_key) break;
4023 hh = hh->next;
4024 }
4025 h->next = hh->next;
4026 hh->next = h;
4027 }
4028 }
4029
4030 hostlist = addrlist->host_list = newlist;
4031 }
4032
4033 /* Sort out the default port. */
4034
4035 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
4036
4037 /* For each host-plus-IP-address on the list:
4038
4039 . If this is a continued delivery and the host isn't the one with the
4040 current connection, skip.
4041
4042 . If the status is unusable (i.e. previously failed or retry checked), skip.
4043
4044 . If no IP address set, get the address, either by turning the name into
4045 an address, calling gethostbyname if gethostbyname is on, or by calling
4046 the DNS. The DNS may yield multiple addresses, in which case insert the
4047 extra ones into the list.
4048
4049 . Get the retry data if not previously obtained for this address and set the
4050 field which remembers the state of this address. Skip if the retry time is
4051 not reached. If not, remember whether retry data was found. The retry string
4052 contains both the name and the IP address.
4053
4054 . Scan the list of addresses and mark those whose status is DEFER as
4055 PENDING_DEFER. These are the only ones that will be processed in this cycle
4056 of the hosts loop.
4057
4058 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
4059 Some addresses may be successfully delivered, others may fail, and yet
4060 others may get temporary errors and so get marked DEFER.
4061
4062 . The return from the delivery attempt is OK if a connection was made and a
4063 valid SMTP dialogue was completed. Otherwise it is DEFER.
4064
4065 . If OK, add a "remove" retry item for this host/IPaddress, if any.
4066
4067 . If fail to connect, or other defer state, add a retry item.
4068
4069 . If there are any addresses whose status is still DEFER, carry on to the
4070 next host/IPaddress, unless we have tried the number of hosts given
4071 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
4072 there is some fancy logic for hosts_max_try that means its limit can be
4073 overstepped in some circumstances.
4074
4075 If we get to the end of the list, all hosts have deferred at least one address,
4076 or not reached their retry times. If delay_after_cutoff is unset, it requests a
4077 delivery attempt to those hosts whose last try was before the arrival time of
4078 the current message. To cope with this, we have to go round the loop a second
4079 time. After that, set the status and error data for any addresses that haven't
4080 had it set already. */
4081
4082 for (cutoff_retry = 0;
4083 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
4084 cutoff_retry++)
4085 {
4086 host_item *nexthost = NULL;
4087 int unexpired_hosts_tried = 0;
4088 BOOL continue_host_tried = FALSE;
4089
4090 retry_non_continued:
4091 for (host = hostlist;
4092 host
4093 && unexpired_hosts_tried < ob->hosts_max_try
4094 && total_hosts_tried < ob->hosts_max_try_hardlimit;
4095 host = nexthost)
4096 {
4097 int rc;
4098 int host_af;
4099 uschar *rs;
4100 BOOL host_is_expired = FALSE;
4101 BOOL message_defer = FALSE;
4102 BOOL some_deferred = FALSE;
4103 address_item *first_addr = NULL;
4104 uschar *interface = NULL;
4105 uschar *retry_host_key = NULL;
4106 uschar *retry_message_key = NULL;
4107 uschar *serialize_key = NULL;
4108
4109 /* Default next host is next host. :-) But this can vary if the
4110 hosts_max_try limit is hit (see below). It may also be reset if a host
4111 address is looked up here (in case the host was multihomed). */
4112
4113 nexthost = host->next;
4114
4115 /* If the address hasn't yet been obtained from the host name, look it up
4116 now, unless the host is already marked as unusable. If it is marked as
4117 unusable, it means that the router was unable to find its IP address (in
4118 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
4119 the lookup failed last time. We don't get this far if *all* MX records
4120 point to non-existent hosts; that is treated as a hard error.
4121
4122 We can just skip this host entirely. When the hosts came from the router,
4123 the address will timeout based on the other host(s); when the address is
4124 looked up below, there is an explicit retry record added.
4125
4126 Note that we mustn't skip unusable hosts if the address is not unset; they
4127 may be needed as expired hosts on the 2nd time round the cutoff loop. */
4128
4129 if (!host->address)
4130 {
4131 int new_port, flags;
4132 host_item *hh;
4133
4134 if (host->status >= hstatus_unusable)
4135 {
4136 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
4137 host->name);
4138 continue;
4139 }
4140
4141 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
4142
4143 /* The host name is permitted to have an attached port. Find it, and
4144 strip it from the name. Just remember it for now. */
4145
4146 new_port = host_item_get_port(host);
4147
4148 /* Count hosts looked up */
4149
4150 hosts_looked_up++;
4151
4152 /* Find by name if so configured, or if it's an IP address. We don't
4153 just copy the IP address, because we need the test-for-local to happen. */
4154
4155 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
4156 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
4157 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
4158
4159 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
4160 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
4161 else
4162 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
4163 &ob->dnssec, /* domains for request/require */
4164 NULL, NULL);
4165
4166 /* Update the host (and any additional blocks, resulting from
4167 multihoming) with a host-specific port, if any. */
4168
4169 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
4170
4171 /* Failure to find the host at this time (usually DNS temporary failure)
4172 is really a kind of routing failure rather than a transport failure.
4173 Therefore we add a retry item of the routing kind, not to stop us trying
4174 to look this name up here again, but to ensure the address gets timed
4175 out if the failures go on long enough. A complete failure at this point
4176 commonly points to a configuration error, but the best action is still
4177 to carry on for the next host. */
4178
4179 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
4180 {
4181 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
4182 expired = FALSE;
4183 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
4184 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
4185 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
4186 host->status = hstatus_unusable;
4187
4188 for (addr = addrlist; addr; addr = addr->next)
4189 {
4190 if (addr->transport_return != DEFER) continue;
4191 addr->basic_errno = ERRNO_UNKNOWNHOST;
4192 addr->message = string_sprintf(
4193 rc == HOST_FIND_SECURITY
4194 ? "lookup of IP address for %s was insecure"
4195 : "failed to lookup IP address for %s",
4196 host->name);
4197 }
4198 continue;
4199 }
4200
4201 /* If the host is actually the local host, we may have a problem, or
4202 there may be some cunning configuration going on. In the problem case,
4203 log things and give up. The default transport status is already DEFER. */
4204
4205 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
4206 {
4207 for (addr = addrlist; addr; addr = addr->next)
4208 {
4209 addr->basic_errno = 0;
4210 addr->message = string_sprintf("%s transport found host %s to be "
4211 "local", tblock->name, host->name);
4212 }
4213 goto END_TRANSPORT;
4214 }
4215 } /* End of block for IP address lookup */
4216
4217 /* If this is a continued delivery, we are interested only in the host
4218 which matches the name of the existing open channel. The check is put
4219 here after the local host lookup, in case the name gets expanded as a
4220 result of the lookup. Set expired FALSE, to save the outer loop executing
4221 twice. */
4222
4223 if (continue_hostname)
4224 if ( Ustrcmp(continue_hostname, host->name) != 0
4225 || Ustrcmp(continue_host_address, host->address) != 0
4226 )
4227 {
4228 expired = FALSE;
4229 continue; /* With next host */
4230 }
4231 else
4232 continue_host_tried = TRUE;
4233
4234 /* Reset the default next host in case a multihomed host whose addresses
4235 are not looked up till just above added to the host list. */
4236
4237 nexthost = host->next;
4238
4239 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
4240 domain is in queue_smtp_domains, we don't actually want to attempt any
4241 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
4242 there is a lookup defer in queue_smtp_domains, proceed as if the domain
4243 were not in it. We don't want to hold up all SMTP deliveries! Except when
4244 doing a two-stage queue run, don't do this if forcing. */
4245
4246 if ((!deliver_force || queue_2stage) && (queue_smtp ||
4247 match_isinlist(addrlist->domain,
4248 (const uschar **)&queue_smtp_domains, 0,
4249 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
4250 {
4251 expired = FALSE;
4252 for (addr = addrlist; addr; addr = addr->next)
4253 if (addr->transport_return == DEFER)
4254 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
4255 continue; /* With next host */
4256 }
4257
4258 /* Count hosts being considered - purely for an intelligent comment
4259 if none are usable. */
4260
4261 hosts_total++;
4262
4263 /* Set $host and $host address now in case they are needed for the
4264 interface expansion or the serialize_hosts check; they remain set if an
4265 actual delivery happens. */
4266
4267 deliver_host = host->name;
4268 deliver_host_address = host->address;
4269 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
4270 : host->dnssec == DS_NO ? US"no"
4271 : US"";
4272
4273 /* Set up a string for adding to the retry key if the port number is not
4274 the standard SMTP port. A host may have its own port setting that overrides
4275 the default. */
4276
4277 pistring = string_sprintf(":%d", host->port == PORT_NONE
4278 ? defport : host->port);
4279 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
4280
4281 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
4282 string is set, even if constant (as different transports can have different
4283 constant settings), we must add it to the key that is used for retries,
4284 because connections to the same host from a different interface should be
4285 treated separately. */
4286
4287 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
4288 if ((rs = ob->interface) && *rs)
4289 {
4290 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
4291 return FALSE;
4292 pistring = string_sprintf("%s/%s", pistring, interface);
4293 }
4294
4295 /* The first time round the outer loop, check the status of the host by
4296 inspecting the retry data. The second time round, we are interested only
4297 in expired hosts that haven't been tried since this message arrived. */
4298
4299 if (cutoff_retry == 0)
4300 {
4301 BOOL incl_ip;
4302 /* Ensure the status of the address is set by checking retry data if
4303 necessary. There may be host-specific retry data (applicable to all
4304 messages) and also data for retries of a specific message at this host.
4305 If either of these retry records are actually read, the keys used are
4306 returned to save recomputing them later. */
4307
4308 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4309 US"retry_include_ip_address", ob->retry_include_ip_address,
4310 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4311 continue; /* with next host */
4312
4313 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4314 incl_ip, &retry_host_key, &retry_message_key);
4315
4316 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4317 (host->address == NULL)? US"" : host->address, pistring,
4318 (host->status == hstatus_usable)? "usable" :
4319 (host->status == hstatus_unusable)? "unusable" :
4320 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
4321
4322 /* Skip this address if not usable at this time, noting if it wasn't
4323 actually expired, both locally and in the address. */
4324
4325 switch (host->status)
4326 {
4327 case hstatus_unusable:
4328 expired = FALSE;
4329 setflag(addrlist, af_retry_skipped);
4330 /* Fall through */
4331
4332 case hstatus_unusable_expired:
4333 switch (host->why)
4334 {
4335 case hwhy_retry: hosts_retry++; break;
4336 case hwhy_failed: hosts_fail++; break;
4337 case hwhy_insecure:
4338 case hwhy_deferred: hosts_defer++; break;
4339 }
4340
4341 /* If there was a retry message key, implying that previously there
4342 was a message-specific defer, we don't want to update the list of
4343 messages waiting for these hosts. */
4344
4345 if (retry_message_key) update_waiting = FALSE;
4346 continue; /* With the next host or IP address */
4347 }
4348 }
4349
4350 /* Second time round the loop: if the address is set but expired, and
4351 the message is newer than the last try, let it through. */
4352
4353 else
4354 {
4355 if ( !host->address
4356 || host->status != hstatus_unusable_expired
4357 || host->last_try > received_time.tv_sec)
4358 continue;
4359 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4360 host->name, host->address, pistring);
4361 host_is_expired = TRUE;
4362 }
4363
4364 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4365 it remains TRUE only if all hosts are expired and none are actually tried.
4366 */
4367
4368 expired = FALSE;
4369
4370 /* If this host is listed as one to which access must be serialized,
4371 see if another Exim process has a connection to it, and if so, skip
4372 this host. If not, update the database to record our connection to it
4373 and remember this for later deletion. Do not do any of this if we are
4374 sending the message down a pre-existing connection. */
4375
4376 if ( !continue_hostname
4377 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
4378 {
4379 serialize_key = string_sprintf("host-serialize-%s", host->name);
4380 if (!enq_start(serialize_key, 1))
4381 {
4382 DEBUG(D_transport)
4383 debug_printf("skipping host %s because another Exim process "
4384 "is connected to it\n", host->name);
4385 hosts_serial++;
4386 continue;
4387 }
4388 }
4389
4390 /* OK, we have an IP address that is not waiting for its retry time to
4391 arrive (it might be expired) OR (second time round the loop) we have an
4392 expired host that hasn't been tried since the message arrived. Have a go
4393 at delivering the message to it. First prepare the addresses by flushing
4394 out the result of previous attempts, and finding the first address that
4395 is still to be delivered. */
4396
4397 first_addr = prepare_addresses(addrlist, host);
4398
4399 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
4400 message_id, host->name, host->address, addrlist->address,
4401 addrlist->next ? ", ..." : "");
4402
4403 set_process_info("delivering %s to %s [%s] (%s%s)",
4404 message_id, host->name, host->address, addrlist->address,
4405 addrlist->next ? ", ..." : "");
4406
4407 /* This is not for real; don't do the delivery. If there are
4408 any remaining hosts, list them. */
4409
4410 if (dont_deliver)
4411 {
4412 host_item *host2;
4413 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
4414 for (addr = addrlist; addr; addr = addr->next)
4415 {
4416 addr->host_used = host;
4417 addr->special_action = '*';
4418 addr->message = US"delivery bypassed by -N option";
4419 }
4420 DEBUG(D_transport)
4421 {
4422 debug_printf("*** delivery by %s transport bypassed by -N option\n"
4423 "*** host and remaining hosts:\n", tblock->name);
4424 for (host2 = host; host2; host2 = host2->next)
4425 debug_printf(" %s [%s]\n", host2->name,
4426 host2->address ? host2->address : US"unset");
4427 }
4428 rc = OK;
4429 }
4430
4431 /* This is for real. If the host is expired, we don't count it for
4432 hosts_max_retry. This ensures that all hosts must expire before an address
4433 is timed out, unless hosts_max_try_hardlimit (which protects against
4434 lunatic DNS configurations) is reached.
4435
4436 If the host is not expired and we are about to hit the hosts_max_retry
4437 limit, check to see if there is a subsequent hosts with a different MX
4438 value. If so, make that the next host, and don't count this one. This is a
4439 heuristic to make sure that different MXs do get tried. With a normal kind
4440 of retry rule, they would get tried anyway when the earlier hosts were
4441 delayed, but if the domain has a "retry every time" type of rule - as is
4442 often used for the the very large ISPs, that won't happen. */
4443
4444 else
4445 {
4446 host_item * thost;
4447 /* Make a copy of the host if it is local to this invocation
4448 of the transport. */
4449
4450 if (expanded_hosts)
4451 {
4452 thost = store_get(sizeof(host_item));
4453 *thost = *host;
4454 thost->name = string_copy(host->name);
4455 thost->address = string_copy(host->address);
4456 }
4457 else
4458 thost = host;
4459
4460 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
4461 {
4462 host_item *h;
4463 DEBUG(D_transport)
4464 debug_printf("hosts_max_try limit reached with this host\n");
4465 for (h = host; h; h = h->next) if (h->mx != host->mx)
4466 {
4467 nexthost = h;
4468 unexpired_hosts_tried--;
4469 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
4470 "and will be tried\n");
4471 break;
4472 }
4473 }
4474
4475 /* Attempt the delivery. */
4476
4477 total_hosts_tried++;
4478 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
4479 &message_defer, FALSE);
4480
4481 /* Yield is one of:
4482 OK => connection made, each address contains its result;
4483 message_defer is set for message-specific defers (when all
4484 recipients are marked defer)
4485 DEFER => there was a non-message-specific delivery problem;
4486 ERROR => there was a problem setting up the arguments for a filter,
4487 or there was a problem with expanding added headers
4488 */
4489
4490 /* If the result is not OK, there was a non-message-specific problem.
4491 If the result is DEFER, we need to write to the logs saying what happened
4492 for this particular host, except in the case of authentication and TLS
4493 failures, where the log has already been written. If all hosts defer a
4494 general message is written at the end. */
4495
4496 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
4497 && first_addr->basic_errno != ERRNO_TLSFAILURE)
4498 write_logs(host, first_addr->message, first_addr->basic_errno);
4499
4500 #ifndef DISABLE_EVENT
4501 if (rc == DEFER)
4502 deferred_event_raise(first_addr, host);
4503 #endif
4504
4505 /* If STARTTLS was accepted, but there was a failure in setting up the
4506 TLS session (usually a certificate screwup), and the host is not in
4507 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
4508 TLS forcibly turned off. We have to start from scratch with a new SMTP
4509 connection. That's why the retry is done from here, not from within
4510 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
4511 session, so the in-clear transmission after those errors, if permitted,
4512 happens inside smtp_deliver().] */
4513
4514 #ifdef SUPPORT_TLS
4515 if ( rc == DEFER
4516 && first_addr->basic_errno == ERRNO_TLSFAILURE
4517 && ob->tls_tempfail_tryclear
4518 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
4519 )
4520 {
4521 log_write(0, LOG_MAIN,
4522 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
4523 first_addr->message, host->name, host->address);
4524 first_addr = prepare_addresses(addrlist, host);
4525 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
4526 &message_defer, TRUE);
4527 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
4528 write_logs(host, first_addr->message, first_addr->basic_errno);
4529 # ifndef DISABLE_EVENT
4530 if (rc == DEFER)
4531 deferred_event_raise(first_addr, host);
4532 # endif
4533 }
4534 #endif /*SUPPORT_TLS*/
4535 }
4536
4537 /* Delivery attempt finished */
4538
4539 rs = rc == OK ? US"OK"
4540 : rc == DEFER ? US"DEFER"
4541 : rc == ERROR ? US"ERROR"
4542 : US"?";
4543
4544 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
4545 message_id, host->name, host->address, addrlist->address,
4546 addrlist->next ? " (& others)" : "", rs);
4547
4548 /* Release serialization if set up */
4549
4550 if (serialize_key) enq_end(serialize_key);
4551
4552 /* If the result is DEFER, or if a host retry record is known to exist, we
4553 need to add an item to the retry chain for updating the retry database
4554 at the end of delivery. We only need to add the item to the top address,
4555 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
4556 for any other delivery attempts using the same address. (It is copied into
4557 the unusable tree at the outer level, so even if different address blocks
4558 contain the same address, it still won't get tried again.) */
4559
4560 if (rc == DEFER || retry_host_key)
4561 {
4562 int delete_flag = rc != DEFER ? rf_delete : 0;
4563 if (!retry_host_key)
4564 {
4565 BOOL incl_ip;
4566 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4567 US"retry_include_ip_address", ob->retry_include_ip_address,
4568 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4569 incl_ip = TRUE; /* error; use most-specific retry record */
4570
4571 retry_host_key = incl_ip
4572 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
4573 : string_sprintf("T:%S%s", host->name, pistring);
4574 }
4575
4576 /* If a delivery of another message over an existing SMTP connection
4577 yields DEFER, we do NOT set up retry data for the host. This covers the
4578 case when there are delays in routing the addresses in the second message
4579 that are so long that the server times out. This is alleviated by not
4580 routing addresses that previously had routing defers when handling an
4581 existing connection, but even so, this case may occur (e.g. if a
4582 previously happily routed address starts giving routing defers). If the
4583 host is genuinely down, another non-continued message delivery will
4584 notice it soon enough. */
4585
4586 if (delete_flag != 0 || !continue_hostname)
4587 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
4588
4589 /* We may have tried an expired host, if its retry time has come; ensure
4590 the status reflects the expiry for the benefit of any other addresses. */
4591
4592 if (rc == DEFER)
4593 {
4594 host->status = host_is_expired
4595 ? hstatus_unusable_expired : hstatus_unusable;
4596 host->why = hwhy_deferred;
4597 }
4598 }
4599
4600 /* If message_defer is set (host was OK, but every recipient got deferred
4601 because of some message-specific problem), or if that had happened
4602 previously so that a message retry key exists, add an appropriate item
4603 to the retry chain. Note that if there was a message defer but now there is
4604 a host defer, the message defer record gets deleted. That seems perfectly
4605 reasonable. Also, stop the message from being remembered as waiting
4606 for specific hosts. */
4607
4608 if (message_defer || retry_message_key)
4609 {
4610 int delete_flag = message_defer ? 0 : rf_delete;
4611 if (!retry_message_key)
4612 {
4613 BOOL incl_ip;
4614 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4615 US"retry_include_ip_address", ob->retry_include_ip_address,
4616 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4617 incl_ip = TRUE; /* error; use most-specific retry record */
4618
4619 retry_message_key = incl_ip
4620 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4621 message_id)
4622 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4623 }
4624 retry_add_item(addrlist, retry_message_key,
4625 rf_message | rf_host | delete_flag);
4626 update_waiting = FALSE;
4627 }
4628
4629 /* Any return other than DEFER (that is, OK or ERROR) means that the
4630 addresses have got their final statuses filled in for this host. In the OK
4631 case, see if any of them are deferred. */
4632
4633 if (rc == OK)
4634 for (addr = addrlist; addr; addr = addr->next)
4635 if (addr->transport_return == DEFER)
4636 {
4637 some_deferred = TRUE;
4638 break;
4639 }
4640
4641 /* If no addresses deferred or the result was ERROR, return. We do this for
4642 ERROR because a failing filter set-up or add_headers expansion is likely to
4643 fail for any host we try. */
4644
4645 if (rc == ERROR || (rc == OK && !some_deferred))
4646 {
4647 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4648 return TRUE; /* Each address has its status */
4649 }
4650
4651 /* If the result was DEFER or some individual addresses deferred, let
4652 the loop run to try other hosts with the deferred addresses, except for the
4653 case when we were trying to deliver down an existing channel and failed.
4654 Don't try any other hosts in this case. */
4655
4656 if (continue_hostname) break;
4657
4658 /* If the whole delivery, or some individual addresses, were deferred and
4659 there are more hosts that could be tried, do not count this host towards
4660 the hosts_max_try limit if the age of the message is greater than the
4661 maximum retry time for this host. This means we may try try all hosts,
4662 ignoring the limit, when messages have been around for some time. This is
4663 important because if we don't try all hosts, the address will never time
4664 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4665
4666 if ((rc == DEFER || some_deferred) && nexthost)
4667 {
4668 BOOL timedout;
4669 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4670
4671 if (retry && retry->rules)
4672 {
4673 retry_rule *last_rule;
4674 for (last_rule = retry->rules;
4675 last_rule->next;
4676 last_rule = last_rule->next);
4677 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
4678 }
4679 else timedout = TRUE; /* No rule => timed out */
4680
4681 if (timedout)
4682 {
4683 unexpired_hosts_tried--;
4684 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4685 "hosts_max_try (message older than host's retry time)\n");
4686 }
4687 }
4688 } /* End of loop for trying multiple hosts. */
4689
4690 /* If we failed to find a matching host in the list, for an already-open
4691 connection, just close it and start over with the list. This can happen
4692 for routing that changes from run to run, or big multi-IP sites with
4693 round-robin DNS. */
4694
4695 if (continue_hostname && !continue_host_tried)
4696 {
4697 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
4698
4699 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
4700 #ifdef SUPPORT_TLS
4701 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
4702 transport */
4703 /*XXX doublecheck that! */
4704
4705 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
4706 {
4707 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
4708 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
4709 cutthrough.cctx.tls_ctx = NULL;
4710 cutthrough.is_tls = FALSE;
4711 }
4712 else
4713 #else
4714 (void) write(fd, US"QUIT\r\n", 6);
4715 #endif
4716 (void) close(fd);
4717 cutthrough.cctx.sock = -1;
4718 continue_hostname = NULL;
4719 goto retry_non_continued;
4720 }
4721
4722 /* This is the end of the loop that repeats iff expired is TRUE and
4723 ob->delay_after_cutoff is FALSE. The second time round we will
4724 try those hosts that haven't been tried since the message arrived. */
4725
4726 DEBUG(D_transport)
4727 {
4728 debug_printf("all IP addresses skipped or deferred at least one address\n");
4729 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4730 debug_printf("retrying IP addresses not tried since message arrived\n");
4731 }
4732 }
4733
4734
4735 /* Get here if all IP addresses are skipped or defer at least one address. In
4736 MUA wrapper mode, this will happen only for connection or other non-message-
4737 specific failures. Force the delivery status for all addresses to FAIL. */
4738
4739 if (mua_wrapper)
4740 {
4741 for (addr = addrlist; addr; addr = addr->next)
4742 addr->transport_return = FAIL;
4743 goto END_TRANSPORT;
4744 }
4745
4746 /* In the normal, non-wrapper case, add a standard message to each deferred
4747 address if there hasn't been an error, that is, if it hasn't actually been
4748 tried this time. The variable "expired" will be FALSE if any deliveries were
4749 actually tried, or if there was at least one host that was not expired. That
4750 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4751 a delivery has been tried, an error code will be set, and the failing of the
4752 message is handled by the retry code later.
4753
4754 If queue_smtp is set, or this transport was called to send a subsequent message
4755 down an existing TCP/IP connection, and something caused the host not to be
4756 found, we end up here, but can detect these cases and handle them specially. */
4757
4758 for (addr = addrlist; addr; addr = addr->next)
4759 {
4760 /* If host is not NULL, it means that we stopped processing the host list
4761 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4762 means we need to behave as if some hosts were skipped because their retry
4763 time had not come. Specifically, this prevents the address from timing out.
4764 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4765 hosts were tried. */
4766
4767 if (host)
4768 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4769 {
4770 DEBUG(D_transport)
4771 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4772 "hosts were tried\n");
4773 }
4774 else
4775 {
4776 DEBUG(D_transport)
4777 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4778 setflag(addr, af_retry_skipped);
4779 }
4780
4781 if (queue_smtp) /* no deliveries attempted */
4782 {
4783 addr->transport_return = DEFER;
4784 addr->basic_errno = 0;
4785 addr->message = US"SMTP delivery explicitly queued";
4786 }
4787
4788 else if ( addr->transport_return == DEFER
4789 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4790 && !addr->message
4791 )
4792 {
4793 addr->basic_errno = ERRNO_HRETRY;
4794 if (continue_hostname)
4795 addr->message = US"no host found for existing SMTP connection";
4796 else if (expired)
4797 {
4798 setflag(addr, af_pass_message); /* This is not a security risk */
4799 addr->message = string_sprintf(
4800 "all hosts%s have been failing for a long time %s",
4801 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4802 ob->delay_after_cutoff
4803 ? US"(and retry time not reached)"
4804 : US"and were last tried after this message arrived");
4805
4806 /* If we are already using fallback hosts, or there are no fallback hosts
4807 defined, convert the result to FAIL to cause a bounce. */
4808
4809 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4810 addr->transport_return = FAIL;
4811 }
4812 else
4813 {
4814 const char * s;
4815 if (hosts_retry == hosts_total)
4816 s = "retry time not reached for any host%s";
4817 else if (hosts_fail == hosts_total)
4818 s = "all host address lookups%s failed permanently";
4819 else if (hosts_defer == hosts_total)
4820 s = "all host address lookups%s failed temporarily";
4821 else if (hosts_serial == hosts_total)
4822 s = "connection limit reached for all hosts%s";
4823 else if (hosts_fail+hosts_defer == hosts_total)
4824 s = "all host address lookups%s failed";
4825 else
4826 s = "some host address lookups failed and retry time "
4827 "not reached for other hosts or connection limit reached%s";
4828
4829 addr->message = string_sprintf(s,
4830 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4831 }
4832 }
4833 }
4834
4835 /* Update the database which keeps information about which messages are waiting
4836 for which hosts to become available. For some message-specific errors, the
4837 update_waiting flag is turned off because we don't want follow-on deliveries in
4838 those cases. If this transport instance is explicitly limited to one message
4839 per connection then follow-on deliveries are not possible and there's no need
4840 to create/update the per-transport wait-<transport_name> database. */
4841
4842 if (update_waiting && tblock->connection_max_messages != 1)
4843 transport_update_waiting(hostlist, tblock->name);
4844
4845 END_TRANSPORT:
4846
4847 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4848
4849 return TRUE; /* Each address has its status */
4850 }
4851
4852 #endif /*!MACRO_PREDEF*/
4853 /* vi: aw ai sw=2
4854 */
4855 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.