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[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 uschar
1340 ehlo_response(uschar * buf, uschar 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 #endif
1349
1350 if ( checks & OPTION_IGNQ
1351 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1352 PCRE_EOPT, NULL, 0) < 0)
1353 checks &= ~OPTION_IGNQ;
1354
1355 if ( checks & OPTION_CHUNKING
1356 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1357 checks &= ~OPTION_CHUNKING;
1358
1359 #ifndef DISABLE_PRDR
1360 if ( checks & OPTION_PRDR
1361 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1362 checks &= ~OPTION_PRDR;
1363 #endif
1364
1365 #ifdef SUPPORT_I18N
1366 if ( checks & OPTION_UTF8
1367 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1368 checks &= ~OPTION_UTF8;
1369 #endif
1370
1371 if ( checks & OPTION_DSN
1372 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1373 checks &= ~OPTION_DSN;
1374
1375 if ( checks & OPTION_PIPE
1376 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1377 PCRE_EOPT, NULL, 0) < 0)
1378 checks &= ~OPTION_PIPE;
1379
1380 if ( checks & OPTION_SIZE
1381 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1382 checks &= ~OPTION_SIZE;
1383
1384 return checks;
1385 }
1386
1387
1388
1389 /* Callback for emitting a BDAT data chunk header.
1390
1391 If given a nonzero size, first flush any buffered SMTP commands
1392 then emit the command.
1393
1394 Reap previous SMTP command responses if requested, and always reap
1395 the response from a previous BDAT command.
1396
1397 Args:
1398 tctx transport context
1399 chunk_size value for SMTP BDAT command
1400 flags
1401 tc_chunk_last add LAST option to SMTP BDAT command
1402 tc_reap_prev reap response to previous SMTP commands
1403
1404 Returns: OK or ERROR
1405 */
1406
1407 static int
1408 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1409 unsigned flags)
1410 {
1411 smtp_transport_options_block * ob =
1412 (smtp_transport_options_block *)(tctx->tblock->options_block);
1413 smtp_context * sx = tctx->smtp_context;
1414 int cmd_count = 0;
1415 int prev_cmd_count;
1416
1417 /* Write SMTP chunk header command. If not reaping responses, note that
1418 there may be more writes (like, the chunk data) done soon. */
1419
1420 if (chunk_size > 0)
1421 {
1422 if((cmd_count = smtp_write_command(&sx->outblock,
1423 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1424 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1425 ) < 0) return ERROR;
1426 if (flags & tc_chunk_last)
1427 data_command = string_copy(big_buffer); /* Save for later error message */
1428 }
1429
1430 prev_cmd_count = cmd_count += sx->cmd_count;
1431
1432 /* Reap responses for any previous, but not one we just emitted */
1433
1434 if (chunk_size > 0)
1435 prev_cmd_count--;
1436 if (sx->pending_BDAT)
1437 prev_cmd_count--;
1438
1439 if (flags & tc_reap_prev && prev_cmd_count > 0)
1440 {
1441 DEBUG(D_transport) debug_printf("look for %d responses"
1442 " for previous pipelined cmds\n", prev_cmd_count);
1443
1444 switch(sync_responses(sx, prev_cmd_count, 0))
1445 {
1446 case 1: /* 2xx (only) => OK */
1447 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1448 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1449 case 0: break; /* No 2xx or 5xx, but no probs */
1450
1451 case -1: /* Timeout on RCPT */
1452 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1453 }
1454 cmd_count = 1;
1455 if (!sx->pending_BDAT)
1456 pipelining_active = FALSE;
1457 }
1458
1459 /* Reap response for an outstanding BDAT */
1460
1461 if (sx->pending_BDAT)
1462 {
1463 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1464
1465 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1466 ob->command_timeout))
1467 {
1468 if (errno == 0 && sx->buffer[0] == '4')
1469 {
1470 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1471 sx->addrlist->more_errno |=
1472 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1473 }
1474 return ERROR;
1475 }
1476 cmd_count--;
1477 sx->pending_BDAT = FALSE;
1478 pipelining_active = FALSE;
1479 }
1480 else if (chunk_size > 0)
1481 sx->pending_BDAT = TRUE;
1482
1483
1484 sx->cmd_count = cmd_count;
1485 return OK;
1486 }
1487
1488
1489
1490 /*************************************************
1491 * Make connection for given message *
1492 *************************************************/
1493
1494 /*
1495 Arguments:
1496 ctx connection context
1497 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1498 a second attempt after TLS initialization fails
1499
1500 Returns: OK - the connection was made and the delivery attempted;
1501 fd is set in the conn context, tls_out set up.
1502 DEFER - the connection could not be made, or something failed
1503 while setting up the SMTP session, or there was a
1504 non-message-specific error, such as a timeout.
1505 ERROR - helo_data or add_headers or authenticated_sender is
1506 specified for this transport, and the string failed
1507 to expand
1508 */
1509 int
1510 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1511 {
1512 #if defined(SUPPORT_TLS) && defined(SUPPORT_DANE)
1513 dns_answer tlsa_dnsa;
1514 #endif
1515 BOOL pass_message = FALSE;
1516 uschar * message = NULL;
1517 int yield = OK;
1518 int rc;
1519
1520 sx->ob = (smtp_transport_options_block *) sx->tblock->options_block;
1521
1522 sx->lmtp = strcmpic(sx->ob->protocol, US"lmtp") == 0;
1523 sx->smtps = strcmpic(sx->ob->protocol, US"smtps") == 0;
1524 sx->ok = FALSE;
1525 sx->send_rset = TRUE;
1526 sx->send_quit = TRUE;
1527 sx->setting_up = TRUE;
1528 sx->esmtp = TRUE;
1529 sx->esmtp_sent = FALSE;
1530 #ifdef SUPPORT_I18N
1531 sx->utf8_needed = FALSE;
1532 #endif
1533 sx->dsn_all_lasthop = TRUE;
1534 #if defined(SUPPORT_TLS) && defined(SUPPORT_DANE)
1535 sx->dane = FALSE;
1536 sx->dane_required = verify_check_given_host(&sx->ob->hosts_require_dane, sx->host) == OK;
1537 #endif
1538
1539 if ((sx->max_rcpt = sx->tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1540 sx->peer_offered = 0;
1541 sx->avoid_option = 0;
1542 sx->igquotstr = US"";
1543 if (!sx->helo_data) sx->helo_data = sx->ob->helo_data;
1544 #ifdef EXPERIMENTAL_DSN_INFO
1545 sx->smtp_greeting = NULL;
1546 sx->helo_response = NULL;
1547 #endif
1548
1549 smtp_command = US"initial connection";
1550 sx->buffer[0] = '\0';
1551
1552 /* Set up the buffer for reading SMTP response packets. */
1553
1554 sx->inblock.buffer = sx->inbuffer;
1555 sx->inblock.buffersize = sizeof(sx->inbuffer);
1556 sx->inblock.ptr = sx->inbuffer;
1557 sx->inblock.ptrend = sx->inbuffer;
1558
1559 /* Set up the buffer for holding SMTP commands while pipelining */
1560
1561 sx->outblock.buffer = sx->outbuffer;
1562 sx->outblock.buffersize = sizeof(sx->outbuffer);
1563 sx->outblock.ptr = sx->outbuffer;
1564 sx->outblock.cmd_count = 0;
1565 sx->outblock.authenticating = FALSE;
1566
1567 /* Reset the parameters of a TLS session. */
1568
1569 tls_out.bits = 0;
1570 tls_out.cipher = NULL; /* the one we may use for this transport */
1571 tls_out.ourcert = NULL;
1572 tls_out.peercert = NULL;
1573 tls_out.peerdn = NULL;
1574 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1575 tls_out.sni = NULL;
1576 #endif
1577 tls_out.ocsp = OCSP_NOT_REQ;
1578
1579 /* Flip the legacy TLS-related variables over to the outbound set in case
1580 they're used in the context of the transport. Don't bother resetting
1581 afterward (when being used by a transport) as we're in a subprocess.
1582 For verify, unflipped once the callout is dealt with */
1583
1584 tls_modify_variables(&tls_out);
1585
1586 #ifndef SUPPORT_TLS
1587 if (sx->smtps)
1588 {
1589 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1590 DEFER, FALSE);
1591 return ERROR;
1592 }
1593 #endif
1594
1595 /* Make a connection to the host if this isn't a continued delivery, and handle
1596 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1597 specially so they can be identified for retries. */
1598
1599 if (!continue_hostname)
1600 {
1601 if (sx->verify)
1602 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->interface, sx->port);
1603
1604 /* Get the actual port the connection will use, into sx->host */
1605
1606 smtp_port_for_connect(sx->host, sx->port);
1607
1608 #if defined(SUPPORT_TLS) && defined(SUPPORT_DANE)
1609 /* Do TLSA lookup for DANE */
1610 {
1611 tls_out.dane_verified = FALSE;
1612 tls_out.tlsa_usage = 0;
1613
1614 if (sx->host->dnssec == DS_YES)
1615 {
1616 if( sx->dane_required
1617 || verify_check_given_host(&sx->ob->hosts_try_dane, sx->host) == OK
1618 )
1619 switch (rc = tlsa_lookup(sx->host, &tlsa_dnsa, sx->dane_required))
1620 {
1621 case OK: sx->dane = TRUE;
1622 sx->ob->tls_tempfail_tryclear = FALSE;
1623 break;
1624 case FAIL_FORCED: break;
1625 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1626 string_sprintf("DANE error: tlsa lookup %s",
1627 rc == DEFER ? "DEFER" : "FAIL"),
1628 rc, FALSE);
1629 (void) event_raise(sx->tblock->event_action,
1630 US"dane:fail", sx->dane_required
1631 ? US"dane-required" : US"dnssec-invalid");
1632 return rc;
1633 }
1634 }
1635 else if (sx->dane_required)
1636 {
1637 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1638 string_sprintf("DANE error: %s lookup not DNSSEC", sx->host->name),
1639 FAIL, FALSE);
1640 (void) event_raise(sx->tblock->event_action,
1641 US"dane:fail", US"dane-required");
1642 return FAIL;
1643 }
1644 }
1645 #endif /*DANE*/
1646
1647 /* Make the TCP connection */
1648
1649 sx->inblock.sock = sx->outblock.sock =
1650 smtp_connect(sx->host, sx->host_af, sx->interface,
1651 sx->ob->connect_timeout, sx->tblock);
1652
1653 if (sx->inblock.sock < 0)
1654 {
1655 uschar * msg = NULL;
1656 if (sx->verify)
1657 {
1658 msg = US strerror(errno);
1659 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
1660 }
1661 set_errno_nohost(sx->addrlist,
1662 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1663 sx->verify ? string_sprintf("could not connect: %s", msg)
1664 : NULL,
1665 DEFER, FALSE);
1666 sx->send_quit = FALSE;
1667 return DEFER;
1668 }
1669
1670 /* Expand the greeting message while waiting for the initial response. (Makes
1671 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1672 delayed till here so that $sending_interface and $sending_port are set. */
1673
1674 if (sx->helo_data)
1675 if (!(sx->helo_data = expand_string(sx->helo_data)))
1676 if (sx->verify)
1677 log_write(0, LOG_MAIN|LOG_PANIC,
1678 "<%s>: failed to expand transport's helo_data value for callout: %s",
1679 sx->addrlist->address, expand_string_message);
1680
1681 #ifdef SUPPORT_I18N
1682 if (sx->helo_data)
1683 {
1684 expand_string_message = NULL;
1685 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
1686 &expand_string_message)),
1687 expand_string_message)
1688 if (sx->verify)
1689 log_write(0, LOG_MAIN|LOG_PANIC,
1690 "<%s>: failed to expand transport's helo_data value for callout: %s",
1691 sx->addrlist->address, expand_string_message);
1692 else
1693 sx->helo_data = NULL;
1694 }
1695 #endif
1696
1697 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1698 is nevertheless a reasonably clean way of programming this kind of logic,
1699 where you want to escape on any error. */
1700
1701 if (!sx->smtps)
1702 {
1703 BOOL good_response;
1704
1705 #ifdef TCP_QUICKACK
1706 (void) setsockopt(sx->inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1707 #endif
1708 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1709 '2', sx->ob->command_timeout);
1710 #ifdef EXPERIMENTAL_DSN_INFO
1711 sx->smtp_greeting = string_copy(sx->buffer);
1712 #endif
1713 if (!good_response) goto RESPONSE_FAILED;
1714
1715 #ifndef DISABLE_EVENT
1716 {
1717 uschar * s;
1718 lookup_dnssec_authenticated = sx->host->dnssec==DS_YES ? US"yes"
1719 : sx->host->dnssec==DS_NO ? US"no" : NULL;
1720 s = event_raise(sx->tblock->event_action, US"smtp:connect", sx->buffer);
1721 if (s)
1722 {
1723 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
1724 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1725 DEFER, FALSE);
1726 yield = DEFER;
1727 goto SEND_QUIT;
1728 }
1729 }
1730 #endif
1731
1732 /* Now check if the helo_data expansion went well, and sign off cleanly if
1733 it didn't. */
1734
1735 if (!sx->helo_data)
1736 {
1737 message = string_sprintf("failed to expand helo_data: %s",
1738 expand_string_message);
1739 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1740 yield = DEFER;
1741 goto SEND_QUIT;
1742 }
1743 }
1744
1745 /** Debugging without sending a message
1746 sx->addrlist->transport_return = DEFER;
1747 goto SEND_QUIT;
1748 **/
1749
1750 /* Errors that occur after this point follow an SMTP command, which is
1751 left in big_buffer by smtp_write_command() for use in error messages. */
1752
1753 smtp_command = big_buffer;
1754
1755 /* Tell the remote who we are...
1756
1757 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1758 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1759 greeting is of this form. The assumption was that the far end supports it
1760 properly... but experience shows that there are some that give 5xx responses,
1761 even though the banner includes "ESMTP" (there's a bloody-minded one that
1762 says "ESMTP not spoken here"). Cope with that case.
1763
1764 September 2000: Time has passed, and it seems reasonable now to always send
1765 EHLO at the start. It is also convenient to make the change while installing
1766 the TLS stuff.
1767
1768 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1769 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1770 would be no way to send out the mails, so there is now a host list
1771 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1772 PIPELINING problem as well. Maybe it can also be useful to cure other
1773 problems with broken servers.
1774
1775 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1776 Then somebody tried it with a Microsoft mailer... It seems that all other
1777 mailers use upper case for some reason (the RFC is quite clear about case
1778 independence) so, for peace of mind, I gave in. */
1779
1780 sx->esmtp = verify_check_given_host(&sx->ob->hosts_avoid_esmtp, sx->host) != OK;
1781
1782 /* Alas; be careful, since this goto is not an error-out, so conceivably
1783 we might set data between here and the target which we assume to exist
1784 and be usable. I can see this coming back to bite us. */
1785 #ifdef SUPPORT_TLS
1786 if (sx->smtps)
1787 {
1788 smtp_peer_options |= OPTION_TLS;
1789 suppress_tls = FALSE;
1790 sx->ob->tls_tempfail_tryclear = FALSE;
1791 smtp_command = US"SSL-on-connect";
1792 goto TLS_NEGOTIATE;
1793 }
1794 #endif
1795
1796 if (sx->esmtp)
1797 {
1798 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "%s %s\r\n",
1799 sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
1800 goto SEND_FAILED;
1801 sx->esmtp_sent = TRUE;
1802 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1803 sx->ob->command_timeout))
1804 {
1805 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
1806 {
1807 #ifdef EXPERIMENTAL_DSN_INFO
1808 sx->helo_response = string_copy(sx->buffer);
1809 #endif
1810 goto RESPONSE_FAILED;
1811 }
1812 sx->esmtp = FALSE;
1813 }
1814 #ifdef EXPERIMENTAL_DSN_INFO
1815 sx->helo_response = string_copy(sx->buffer);
1816 #endif
1817 }
1818 else
1819 DEBUG(D_transport)
1820 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1821
1822 if (!sx->esmtp)
1823 {
1824 BOOL good_response;
1825 int n = sizeof(sx->buffer);
1826 uschar * rsp = sx->buffer;
1827
1828 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
1829 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
1830
1831 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
1832 goto SEND_FAILED;
1833 good_response = smtp_read_response(&sx->inblock, rsp, n,
1834 '2', sx->ob->command_timeout);
1835 #ifdef EXPERIMENTAL_DSN_INFO
1836 sx->helo_response = string_copy(rsp);
1837 #endif
1838 if (!good_response)
1839 {
1840 /* Handle special logging for a closed connection after HELO
1841 when had previously sent EHLO */
1842
1843 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1844 {
1845 errno = ERRNO_SMTPCLOSED;
1846 goto EHLOHELO_FAILED;
1847 }
1848 memmove(sx->buffer, rsp, Ustrlen(rsp));
1849 goto RESPONSE_FAILED;
1850 }
1851 }
1852
1853 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
1854
1855 if (sx->esmtp || sx->lmtp)
1856 {
1857 sx->peer_offered = ehlo_response(sx->buffer,
1858 OPTION_TLS /* others checked later */
1859 );
1860
1861 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1862
1863 #ifdef SUPPORT_TLS
1864 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
1865 #endif
1866 }
1867 }
1868
1869 /* For continuing deliveries down the same channel, having re-exec'd the socket
1870 is the standard input; for a socket held open from verify it is recorded
1871 in the cutthrough context block. Either way we don't need to redo EHLO here
1872 (but may need to do so for TLS - see below).
1873 Set up the pointer to where subsequent commands will be left, for
1874 error messages. Note that smtp_peer_options will have been
1875 set from the command line if they were set in the process that passed the
1876 connection on. */
1877
1878 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1879 as the continue goes via transport_pass_socket() and doublefork and exec.
1880 It does not wait. Unclear how we keep separate host's responses
1881 separate - we could match up by host ip+port as a bodge. */
1882
1883 else
1884 {
1885 if (cutthrough.fd >= 0 && cutthrough.callout_hold_only)
1886 {
1887 sx->inblock.sock = sx->outblock.sock = cutthrough.fd;
1888 sx->host->port = sx->port = cutthrough.host.port;
1889 }
1890 else
1891 {
1892 sx->inblock.sock = sx->outblock.sock = 0; /* stdin */
1893 smtp_port_for_connect(sx->host, sx->port); /* Record the port that was used */
1894 }
1895 smtp_command = big_buffer;
1896 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
1897
1898 /* For a continued connection with TLS being proxied for us, or a
1899 held-open verify connection with TLS, nothing more to do. */
1900
1901 if ( continue_proxy_cipher
1902 || (cutthrough.fd >= 0 && cutthrough.callout_hold_only && cutthrough.is_tls)
1903 )
1904 {
1905 sx->peer_offered = smtp_peer_options;
1906 pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
1907 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
1908 continue_proxy_cipher ? "proxied" : "verify conn with");
1909 return OK;
1910 }
1911 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
1912 }
1913
1914 /* If TLS is available on this connection, whether continued or not, attempt to
1915 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1916 send another EHLO - the server may give a different answer in secure mode. We
1917 use a separate buffer for reading the response to STARTTLS so that if it is
1918 negative, the original EHLO data is available for subsequent analysis, should
1919 the client not be required to use TLS. If the response is bad, copy the buffer
1920 for error analysis. */
1921
1922 #ifdef SUPPORT_TLS
1923 if ( smtp_peer_options & OPTION_TLS
1924 && !suppress_tls
1925 && verify_check_given_host(&sx->ob->hosts_avoid_tls, sx->host) != OK
1926 && ( !sx->verify
1927 || verify_check_given_host(&sx->ob->hosts_verify_avoid_tls, sx->host) != OK
1928 ) )
1929 {
1930 uschar buffer2[4096];
1931 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "STARTTLS\r\n") < 0)
1932 goto SEND_FAILED;
1933
1934 /* If there is an I/O error, transmission of this message is deferred. If
1935 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1936 false, we also defer. However, if there is a temporary rejection of STARTTLS
1937 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1938 STARTTLS, we carry on. This means we will try to send the message in clear,
1939 unless the host is in hosts_require_tls (tested below). */
1940
1941 if (!smtp_read_response(&sx->inblock, buffer2, sizeof(buffer2), '2',
1942 sx->ob->command_timeout))
1943 {
1944 if ( errno != 0
1945 || buffer2[0] == 0
1946 || (buffer2[0] == '4' && !sx->ob->tls_tempfail_tryclear)
1947 )
1948 {
1949 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
1950 sx->buffer[sizeof(sx->buffer)-1] = '\0';
1951 goto RESPONSE_FAILED;
1952 }
1953 }
1954
1955 /* STARTTLS accepted: try to negotiate a TLS session. */
1956
1957 else
1958 TLS_NEGOTIATE:
1959 {
1960 address_item * addr;
1961 uschar * errstr;
1962 int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock,
1963 # ifdef SUPPORT_DANE
1964 sx->dane ? &tlsa_dnsa : NULL,
1965 # endif
1966 &errstr);
1967
1968 /* TLS negotiation failed; give an error. From outside, this function may
1969 be called again to try in clear on a new connection, if the options permit
1970 it for this host. */
1971
1972 if (rc != OK)
1973 {
1974 # ifdef SUPPORT_DANE
1975 if (sx->dane)
1976 {
1977 log_write(0, LOG_MAIN,
1978 "DANE attempt failed; TLS connection to %s [%s]: %s",
1979 sx->host->name, sx->host->address, errstr);
1980 (void) event_raise(sx->tblock->event_action,
1981 US"dane:fail", US"validation-failure"); /* could do with better detail */
1982 }
1983 # endif
1984
1985 errno = ERRNO_TLSFAILURE;
1986 message = string_sprintf("TLS session: %s", errstr);
1987 sx->send_quit = FALSE;
1988 goto TLS_FAILED;
1989 }
1990
1991 /* TLS session is set up */
1992
1993 smtp_peer_options_wrap = smtp_peer_options;
1994 for (addr = sx->addrlist; addr; addr = addr->next)
1995 if (addr->transport_return == PENDING_DEFER)
1996 {
1997 addr->cipher = tls_out.cipher;
1998 addr->ourcert = tls_out.ourcert;
1999 addr->peercert = tls_out.peercert;
2000 addr->peerdn = tls_out.peerdn;
2001 addr->ocsp = tls_out.ocsp;
2002 }
2003 }
2004 }
2005
2006 /* if smtps, we'll have smtp_command set to something else; always safe to
2007 reset it here. */
2008 smtp_command = big_buffer;
2009
2010 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2011 helo_data is null, we are dealing with a connection that was passed from
2012 another process, and so we won't have expanded helo_data above. We have to
2013 expand it here. $sending_ip_address and $sending_port are set up right at the
2014 start of the Exim process (in exim.c). */
2015
2016 if (tls_out.active >= 0)
2017 {
2018 char *greeting_cmd;
2019 BOOL good_response;
2020
2021 if (!sx->helo_data && !(sx->helo_data = expand_string(sx->ob->helo_data)))
2022 {
2023 uschar *message = string_sprintf("failed to expand helo_data: %s",
2024 expand_string_message);
2025 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2026 yield = DEFER;
2027 goto SEND_QUIT;
2028 }
2029
2030 /* For SMTPS we need to wait for the initial OK response. */
2031 if (sx->smtps)
2032 {
2033 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
2034 '2', sx->ob->command_timeout);
2035 #ifdef EXPERIMENTAL_DSN_INFO
2036 sx->smtp_greeting = string_copy(sx->buffer);
2037 #endif
2038 if (!good_response) goto RESPONSE_FAILED;
2039 }
2040
2041 if (sx->esmtp)
2042 greeting_cmd = "EHLO";
2043 else
2044 {
2045 greeting_cmd = "HELO";
2046 DEBUG(D_transport)
2047 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2048 }
2049
2050 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "%s %s\r\n",
2051 sx->lmtp ? "LHLO" : greeting_cmd, sx->helo_data) < 0)
2052 goto SEND_FAILED;
2053 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
2054 '2', sx->ob->command_timeout);
2055 #ifdef EXPERIMENTAL_DSN_INFO
2056 sx->helo_response = string_copy(sx->buffer);
2057 #endif
2058 if (!good_response) goto RESPONSE_FAILED;
2059 smtp_peer_options = 0;
2060 }
2061
2062 /* If the host is required to use a secure channel, ensure that we
2063 have one. */
2064
2065 else if ( sx->smtps
2066 # ifdef SUPPORT_DANE
2067 || sx->dane
2068 # endif
2069 || verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
2070 )
2071 {
2072 errno = ERRNO_TLSREQUIRED;
2073 message = string_sprintf("a TLS session is required, but %s",
2074 smtp_peer_options & OPTION_TLS
2075 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2076 # ifdef SUPPORT_DANE
2077 if (sx->dane)
2078 (void) event_raise(sx->tblock->event_action, US"dane:fail",
2079 smtp_peer_options & OPTION_TLS
2080 ? US"validation-failure" /* could do with better detail */
2081 : US"starttls-not-supported");
2082 # endif
2083 goto TLS_FAILED;
2084 }
2085 #endif /*SUPPORT_TLS*/
2086
2087 /* If TLS is active, we have just started it up and re-done the EHLO command,
2088 so its response needs to be analyzed. If TLS is not active and this is a
2089 continued session down a previously-used socket, we haven't just done EHLO, so
2090 we skip this. */
2091
2092 if (continue_hostname == NULL
2093 #ifdef SUPPORT_TLS
2094 || tls_out.active >= 0
2095 #endif
2096 )
2097 {
2098 if (sx->esmtp || sx->lmtp)
2099 {
2100 sx->peer_offered = ehlo_response(sx->buffer,
2101 0 /* no TLS */
2102 | (sx->lmtp && sx->ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2103 | OPTION_CHUNKING
2104 | OPTION_PRDR
2105 #ifdef SUPPORT_I18N
2106 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2107 /*XXX if we hand peercaps on to continued-conn processes,
2108 must not depend on this addr */
2109 #endif
2110 | OPTION_DSN
2111 | OPTION_PIPE
2112 | (sx->ob->size_addition >= 0 ? OPTION_SIZE : 0)
2113 );
2114
2115 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2116 lmtp_ignore_quota option was set. */
2117
2118 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2119
2120 /* If the response to EHLO specified support for the SIZE parameter, note
2121 this, provided size_addition is non-negative. */
2122
2123 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2124
2125 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2126 the current host, esmtp will be false, so PIPELINING can never be used. If
2127 the current host matches hosts_avoid_pipelining, don't do it. */
2128
2129 if ( sx->peer_offered & OPTION_PIPE
2130 && verify_check_given_host(&sx->ob->hosts_avoid_pipelining, sx->host) != OK)
2131 smtp_peer_options |= OPTION_PIPE;
2132
2133 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2134 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2135
2136 if ( sx->peer_offered & OPTION_CHUNKING
2137 && verify_check_given_host(&sx->ob->hosts_try_chunking, sx->host) != OK)
2138 sx->peer_offered &= ~OPTION_CHUNKING;
2139
2140 if (sx->peer_offered & OPTION_CHUNKING)
2141 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2142
2143 #ifndef DISABLE_PRDR
2144 if ( sx->peer_offered & OPTION_PRDR
2145 && verify_check_given_host(&sx->ob->hosts_try_prdr, sx->host) != OK)
2146 sx->peer_offered &= ~OPTION_PRDR;
2147
2148 if (sx->peer_offered & OPTION_PRDR)
2149 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2150 #endif
2151
2152 /* Note if the server supports DSN */
2153 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2154 DEBUG(D_transport) debug_printf("%susing DSN\n",
2155 sx->peer_offered & OPTION_DSN ? "" : "not ");
2156
2157 /* Note if the response to EHLO specifies support for the AUTH extension.
2158 If it has, check that this host is one we want to authenticate to, and do
2159 the business. The host name and address must be available when the
2160 authenticator's client driver is running. */
2161
2162 switch (yield = smtp_auth(sx->buffer, sizeof(sx->buffer), sx->addrlist, sx->host,
2163 sx->ob, sx->esmtp, &sx->inblock, &sx->outblock))
2164 {
2165 default: goto SEND_QUIT;
2166 case OK: break;
2167 case FAIL_SEND: goto SEND_FAILED;
2168 case FAIL: goto RESPONSE_FAILED;
2169 }
2170 }
2171 }
2172 pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2173
2174 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2175 message-specific. */
2176
2177 sx->setting_up = FALSE;
2178
2179 #ifdef SUPPORT_I18N
2180 if (sx->addrlist->prop.utf8_msg)
2181 {
2182 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2183 && !sx->addrlist->prop.utf8_downcvt_maybe;
2184 DEBUG(D_transport) if (!sx->utf8_needed)
2185 debug_printf("utf8: %s downconvert\n",
2186 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2187 }
2188
2189 /* If this is an international message we need the host to speak SMTPUTF8 */
2190 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2191 {
2192 errno = ERRNO_UTF8_FWD;
2193 goto RESPONSE_FAILED;
2194 }
2195 #endif
2196
2197 return OK;
2198
2199
2200 {
2201 int code;
2202
2203 RESPONSE_FAILED:
2204 message = NULL;
2205 sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
2206 sx->buffer, &code, &message, &pass_message);
2207 goto FAILED;
2208
2209 SEND_FAILED:
2210 code = '4';
2211 message = US string_sprintf("send() to %s [%s] failed: %s",
2212 sx->host->name, sx->host->address, strerror(errno));
2213 sx->send_quit = FALSE;
2214 goto FAILED;
2215
2216 EHLOHELO_FAILED:
2217 code = '4';
2218 message = string_sprintf("Remote host closed connection in response to %s"
2219 " (EHLO response was: %s)", smtp_command, sx->buffer);
2220 sx->send_quit = FALSE;
2221 goto FAILED;
2222
2223 /* This label is jumped to directly when a TLS negotiation has failed,
2224 or was not done for a host for which it is required. Values will be set
2225 in message and errno, and setting_up will always be true. Treat as
2226 a temporary error. */
2227
2228 #ifdef SUPPORT_TLS
2229 TLS_FAILED:
2230 code = '4';
2231 goto FAILED;
2232 #endif
2233
2234 /* The failure happened while setting up the call; see if the failure was
2235 a 5xx response (this will either be on connection, or following HELO - a 5xx
2236 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2237 fail all addresses, as this host is never going to accept them. For other
2238 errors during setting up (timeouts or whatever), defer all addresses, and
2239 yield DEFER, so that the host is not tried again for a while.
2240
2241 XXX This peeking for another host feels like a layering violation. We want
2242 to note the host as unusable, but down here we shouldn't know if this was
2243 the last host to try for the addr(list). Perhaps the upper layer should be
2244 the one to do set_errno() ? The problem is that currently the addr is where
2245 errno etc. are stashed, but until we run out of hosts to try the errors are
2246 host-specific. Maybe we should enhance the host_item definition? */
2247
2248 FAILED:
2249 sx->ok = FALSE; /* For when reached by GOTO */
2250 set_errno(sx->addrlist, errno, message,
2251 sx->host->next
2252 ? DEFER
2253 : code == '5'
2254 #ifdef SUPPORT_I18N
2255 || errno == ERRNO_UTF8_FWD
2256 #endif
2257 ? FAIL : DEFER,
2258 pass_message, sx->host
2259 #ifdef EXPERIMENTAL_DSN_INFO
2260 , sx->smtp_greeting, sx->helo_response
2261 #endif
2262 );
2263 yield = DEFER;
2264 }
2265
2266
2267 SEND_QUIT:
2268
2269 if (sx->send_quit)
2270 (void)smtp_write_command(&sx->outblock, SCMD_FLUSH, "QUIT\r\n");
2271
2272 #ifdef SUPPORT_TLS
2273 tls_close(FALSE, TLS_SHUTDOWN_NOWAIT);
2274 #endif
2275
2276 /* Close the socket, and return the appropriate value, first setting
2277 works because the NULL setting is passed back to the calling process, and
2278 remote_max_parallel is forced to 1 when delivering over an existing connection,
2279 */
2280
2281 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2282 if (sx->send_quit)
2283 {
2284 shutdown(sx->outblock.sock, SHUT_WR);
2285 if (fcntl(sx->inblock.sock, F_SETFL, O_NONBLOCK) == 0)
2286 for (rc = 16; read(sx->inblock.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && rc > 0;)
2287 rc--; /* drain socket */
2288 sx->send_quit = FALSE;
2289 }
2290 (void)close(sx->inblock.sock);
2291 sx->inblock.sock = sx->outblock.sock = -1;
2292
2293 #ifndef DISABLE_EVENT
2294 (void) event_raise(sx->tblock->event_action, US"tcp:close", NULL);
2295 #endif
2296
2297 continue_transport = NULL;
2298 continue_hostname = NULL;
2299 return yield;
2300 }
2301
2302
2303
2304
2305 /* Create the string of options that will be appended to the MAIL FROM:
2306 in the connection context buffer */
2307
2308 static int
2309 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2310 {
2311 uschar * p = sx->buffer;
2312 address_item * addr;
2313 int address_count;
2314
2315 *p = 0;
2316
2317 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2318 send it, adding something to the message size to allow for imprecision
2319 and things that get added en route. Exim keeps the number of lines
2320 in a message, so we can give an accurate value for the original message, but we
2321 need some additional to handle added headers. (Double "." characters don't get
2322 included in the count.) */
2323
2324 if ( message_size > 0
2325 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
2326 {
2327 /*XXX problem here under spool_files_wireformat?
2328 Or just forget about lines? Or inflate by a fixed proportion? */
2329
2330 sprintf(CS p, " SIZE=%d", message_size+message_linecount+sx->ob->size_addition);
2331 while (*p) p++;
2332 }
2333
2334 #ifndef DISABLE_PRDR
2335 /* If it supports Per-Recipient Data Reponses, and we have omre than one recipient,
2336 request that */
2337
2338 sx->prdr_active = FALSE;
2339 if (sx->peer_offered & OPTION_PRDR)
2340 for (addr = addrlist; addr; addr = addr->next)
2341 if (addr->transport_return == PENDING_DEFER)
2342 {
2343 for (addr = addr->next; addr; addr = addr->next)
2344 if (addr->transport_return == PENDING_DEFER)
2345 { /* at least two recipients to send */
2346 sx->prdr_active = TRUE;
2347 sprintf(CS p, " PRDR"); p += 5;
2348 break;
2349 }
2350 break;
2351 }
2352 #endif
2353
2354 #ifdef SUPPORT_I18N
2355 /* If it supports internationalised messages, and this meesage need that,
2356 request it */
2357
2358 if ( sx->peer_offered & OPTION_UTF8
2359 && addrlist->prop.utf8_msg
2360 && !addrlist->prop.utf8_downcvt
2361 )
2362 Ustrcpy(p, " SMTPUTF8"), p += 9;
2363 #endif
2364
2365 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
2366 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
2367 addr && address_count < sx->max_rcpt;
2368 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2369 {
2370 address_count++;
2371 if (!(addr->dsn_flags & rf_dsnlasthop))
2372 {
2373 sx->dsn_all_lasthop = FALSE;
2374 break;
2375 }
2376 }
2377
2378 /* Add any DSN flags to the mail command */
2379
2380 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
2381 {
2382 if (dsn_ret == dsn_ret_hdrs)
2383 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2384 else if (dsn_ret == dsn_ret_full)
2385 { Ustrcpy(p, " RET=FULL"); p += 9; }
2386
2387 if (dsn_envid)
2388 {
2389 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
2390 while (*p) p++;
2391 }
2392 }
2393
2394 /* If an authenticated_sender override has been specified for this transport
2395 instance, expand it. If the expansion is forced to fail, and there was already
2396 an authenticated_sender for this message, the original value will be used.
2397 Other expansion failures are serious. An empty result is ignored, but there is
2398 otherwise no check - this feature is expected to be used with LMTP and other
2399 cases where non-standard addresses (e.g. without domains) might be required. */
2400
2401 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->ob))
2402 return ERROR;
2403
2404 return OK;
2405 }
2406
2407
2408 static void
2409 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
2410 {
2411 uschar * p = sx->buffer;
2412 *p = 0;
2413
2414 /* Add any DSN flags to the rcpt command */
2415
2416 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2417 {
2418 if (addr->dsn_flags & rf_dsnflags)
2419 {
2420 int i;
2421 BOOL first = TRUE;
2422
2423 Ustrcpy(p, " NOTIFY=");
2424 while (*p) p++;
2425 for (i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
2426 {
2427 if (!first) *p++ = ',';
2428 first = FALSE;
2429 Ustrcpy(p, rf_names[i]);
2430 while (*p) p++;
2431 }
2432 }
2433
2434 if (addr->dsn_orcpt)
2435 {
2436 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
2437 addr->dsn_orcpt);
2438 while (*p) p++;
2439 }
2440 }
2441 }
2442
2443
2444
2445 /*
2446 Return:
2447 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
2448 -1 MAIL response error
2449 -2 any non-MAIL read i/o error
2450 -3 non-MAIL response timeout
2451 -4 internal error; channel still usable
2452 -5 transmit failed
2453 */
2454
2455 int
2456 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
2457 {
2458 address_item * addr;
2459 int address_count;
2460 int rc;
2461
2462 if (build_mailcmd_options(sx, sx->first_addr) != OK)
2463 {
2464 *yield = ERROR;
2465 return -4;
2466 }
2467
2468 /* From here until we send the DATA command, we can make use of PIPELINING
2469 if the server host supports it. The code has to be able to check the responses
2470 at any point, for when the buffer fills up, so we write it totally generally.
2471 When PIPELINING is off, each command written reports that it has flushed the
2472 buffer. */
2473
2474 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
2475
2476 {
2477 uschar * s = sx->from_addr;
2478 #ifdef SUPPORT_I18N
2479 uschar * errstr = NULL;
2480
2481 /* If we must downconvert, do the from-address here. Remember we had to
2482 for the to-addresses (done below), and also (ugly) for re-doing when building
2483 the delivery log line. */
2484
2485 if ( sx->addrlist->prop.utf8_msg
2486 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
2487 )
2488 {
2489 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
2490 {
2491 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2492 *yield = ERROR;
2493 return -4;
2494 }
2495 setflag(sx->addrlist, af_utf8_downcvt);
2496 }
2497 #endif
2498
2499 rc = smtp_write_command(&sx->outblock, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
2500 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
2501 }
2502
2503 mail_command = string_copy(big_buffer); /* Save for later error message */
2504
2505 switch(rc)
2506 {
2507 case -1: /* Transmission error */
2508 return -5;
2509
2510 case +1: /* Cmd was sent */
2511 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
2512 sx->ob->command_timeout))
2513 {
2514 if (errno == 0 && sx->buffer[0] == '4')
2515 {
2516 errno = ERRNO_MAIL4XX;
2517 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2518 }
2519 return -1;
2520 }
2521 sx->pending_MAIL = FALSE;
2522 break;
2523
2524 /* otherwise zero: command queued for pipeline */
2525 }
2526
2527 /* Pass over all the relevant recipient addresses for this host, which are the
2528 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2529 several before we have to read the responses for those seen so far. This
2530 checking is done by a subroutine because it also needs to be done at the end.
2531 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
2532 the next one if not all are sent.
2533
2534 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2535 last address because we want to abort if any recipients have any kind of
2536 problem, temporary or permanent. We know that all recipient addresses will have
2537 the PENDING_DEFER status, because only one attempt is ever made, and we know
2538 that max_rcpt will be large, so all addresses will be done at once.
2539
2540 For verify we flush the pipeline after any (the only) rcpt address. */
2541
2542 for (addr = sx->first_addr, address_count = 0;
2543 addr && address_count < sx->max_rcpt;
2544 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2545 {
2546 int count;
2547 BOOL no_flush;
2548 uschar * rcpt_addr;
2549
2550 if (tcp_out_fastopen && !tcp_out_fastopen_logged)
2551 {
2552 setflag(addr, af_tcp_fastopen_conn);
2553 if (tcp_out_fastopen > 1) setflag(addr, af_tcp_fastopen);
2554 }
2555
2556 addr->dsn_aware = sx->peer_offered & OPTION_DSN
2557 ? dsn_support_yes : dsn_support_no;
2558
2559 address_count++;
2560 no_flush = pipelining_active && !sx->verify
2561 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
2562
2563 build_rcptcmd_options(sx, addr);
2564
2565 /* Now send the RCPT command, and process outstanding responses when
2566 necessary. After a timeout on RCPT, we just end the function, leaving the
2567 yield as OK, because this error can often mean that there is a problem with
2568 just one address, so we don't want to delay the host. */
2569
2570 rcpt_addr = transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes);
2571
2572 #ifdef SUPPORT_I18N
2573 if ( testflag(sx->addrlist, af_utf8_downcvt)
2574 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
2575 )
2576 {
2577 /*XXX could we use a per-address errstr here? Not fail the whole send? */
2578 errno = ERRNO_EXPANDFAIL;
2579 return -5; /*XXX too harsh? */
2580 }
2581 #endif
2582
2583 count = smtp_write_command(&sx->outblock, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
2584 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
2585
2586 if (count < 0) return -5;
2587 if (count > 0)
2588 {
2589 switch(sync_responses(sx, count, 0))
2590 {
2591 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
2592 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2593 break;
2594
2595 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2596 if (!sx->lmtp) /* can't tell about progress yet */
2597 sx->completed_addr = TRUE;
2598 case 0: /* No 2xx or 5xx, but no probs */
2599 break;
2600
2601 case -1: return -3; /* Timeout on RCPT */
2602 case -2: return -2; /* non-MAIL read i/o error */
2603 default: return -1; /* any MAIL error */
2604 }
2605 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
2606 }
2607 } /* Loop for next address */
2608
2609 tcp_out_fastopen_logged = TRUE;
2610 sx->next_addr = addr;
2611 return 0;
2612 }
2613
2614
2615 #ifdef SUPPORT_TLS
2616 /*****************************************************
2617 * Proxy TLS connection for another transport process *
2618 ******************************************************/
2619 /*
2620 Close the unused end of the pipe, fork once more, then use the given buffer
2621 as a staging area, and select on both the given fd and the TLS'd client-fd for
2622 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
2623 Do blocking full-size writes, and reads under a timeout. Once both input
2624 channels are closed, exit the process.
2625
2626 Arguments:
2627 buf space to use for buffering
2628 bufsiz size of buffer
2629 pfd pipe filedescriptor array; [0] is comms to proxied process
2630 timeout per-read timeout, seconds
2631 */
2632
2633 void
2634 smtp_proxy_tls(uschar * buf, size_t bsize, int * pfd, int timeout)
2635 {
2636 fd_set rfds, efds;
2637 int max_fd = MAX(pfd[0], tls_out.active) + 1;
2638 int rc, i, fd_bits, nbytes;
2639
2640 close(pfd[1]);
2641 if ((rc = fork()))
2642 {
2643 DEBUG(D_transport) debug_printf("proxy-proc final-pid %d\n", rc);
2644 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
2645 }
2646
2647 if (running_in_test_harness) millisleep(100); /* let parent debug out */
2648 set_process_info("proxying TLS connection for continued transport");
2649 FD_ZERO(&rfds);
2650 FD_SET(tls_out.active, &rfds);
2651 FD_SET(pfd[0], &rfds);
2652
2653 for (fd_bits = 3; fd_bits; )
2654 {
2655 time_t time_left = timeout;
2656 time_t time_start = time(NULL);
2657
2658 /* wait for data */
2659 efds = rfds;
2660 do
2661 {
2662 struct timeval tv = { time_left, 0 };
2663
2664 rc = select(max_fd,
2665 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
2666
2667 if (rc < 0 && errno == EINTR)
2668 if ((time_left -= time(NULL) - time_start) > 0) continue;
2669
2670 if (rc <= 0)
2671 {
2672 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
2673 goto done;
2674 }
2675
2676 if (FD_ISSET(tls_out.active, &efds) || FD_ISSET(pfd[0], &efds))
2677 {
2678 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
2679 FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
2680 goto done;
2681 }
2682 }
2683 while (rc < 0 || !(FD_ISSET(tls_out.active, &rfds) || FD_ISSET(pfd[0], &rfds)));
2684
2685 /* handle inbound data */
2686 if (FD_ISSET(tls_out.active, &rfds))
2687 if ((rc = tls_read(FALSE, buf, bsize)) <= 0)
2688 {
2689 fd_bits &= ~1;
2690 FD_CLR(tls_out.active, &rfds);
2691 shutdown(pfd[0], SHUT_WR);
2692 timeout = 5;
2693 }
2694 else
2695 {
2696 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2697 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
2698 }
2699 else if (fd_bits & 1)
2700 FD_SET(tls_out.active, &rfds);
2701
2702 /* handle outbound data */
2703 if (FD_ISSET(pfd[0], &rfds))
2704 if ((rc = read(pfd[0], buf, bsize)) <= 0)
2705 {
2706 fd_bits = 0;
2707 tls_close(FALSE, TLS_SHUTDOWN_NOWAIT);
2708 }
2709 else
2710 {
2711 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2712 if ((i = tls_write(FALSE, buf + nbytes, rc - nbytes, FALSE)) < 0)
2713 goto done;
2714 }
2715 else if (fd_bits & 2)
2716 FD_SET(pfd[0], &rfds);
2717 }
2718
2719 done:
2720 if (running_in_test_harness) millisleep(100); /* let logging complete */
2721 exim_exit(0, US"TLS proxy");
2722 }
2723 #endif
2724
2725
2726 /*************************************************
2727 * Deliver address list to given host *
2728 *************************************************/
2729
2730 /* If continue_hostname is not null, we get here only when continuing to
2731 deliver down an existing channel. The channel was passed as the standard
2732 input. TLS is never active on a passed channel; the previous process always
2733 closes it down before passing the connection on.
2734
2735 Otherwise, we have to make a connection to the remote host, and do the
2736 initial protocol exchange.
2737
2738 When running as an MUA wrapper, if the sender or any recipient is rejected,
2739 temporarily or permanently, we force failure for all recipients.
2740
2741 Arguments:
2742 addrlist chain of potential addresses to deliver; only those whose
2743 transport_return field is set to PENDING_DEFER are currently
2744 being processed; others should be skipped - they have either
2745 been delivered to an earlier host or IP address, or been
2746 failed by one of them.
2747 host host to deliver to
2748 host_af AF_INET or AF_INET6
2749 defport default TCP/IP port to use if host does not specify, in host
2750 byte order
2751 interface interface to bind to, or NULL
2752 tblock transport instance block
2753 message_defer set TRUE if yield is OK, but all addresses were deferred
2754 because of a non-recipient, non-host failure, that is, a
2755 4xx response to MAIL FROM, DATA, or ".". This is a defer
2756 that is specific to the message.
2757 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2758 a second attempt after TLS initialization fails
2759
2760 Returns: OK - the connection was made and the delivery attempted;
2761 the result for each address is in its data block.
2762 DEFER - the connection could not be made, or something failed
2763 while setting up the SMTP session, or there was a
2764 non-message-specific error, such as a timeout.
2765 ERROR - a filter command is specified for this transport,
2766 and there was a problem setting it up; OR helo_data
2767 or add_headers or authenticated_sender is specified
2768 for this transport, and the string failed to expand
2769 */
2770
2771 static int
2772 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
2773 uschar *interface, transport_instance *tblock,
2774 BOOL *message_defer, BOOL suppress_tls)
2775 {
2776 address_item *addr;
2777 int yield = OK;
2778 int save_errno;
2779 int rc;
2780 struct timeval start_delivery_time;
2781
2782 BOOL pass_message = FALSE;
2783 uschar *message = NULL;
2784 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
2785
2786 smtp_context sx;
2787
2788 gettimeofday(&start_delivery_time, NULL);
2789 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
2790 *message_defer = FALSE;
2791
2792 sx.addrlist = addrlist;
2793 sx.host = host;
2794 sx.host_af = host_af,
2795 sx.port = defport;
2796 sx.interface = interface;
2797 sx.helo_data = NULL;
2798 sx.tblock = tblock;
2799 sx.verify = FALSE;
2800
2801 /* Get the channel set up ready for a message (MAIL FROM being the next
2802 SMTP command to send */
2803
2804 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
2805 return rc;
2806
2807 /* If there is a filter command specified for this transport, we can now
2808 set it up. This cannot be done until the identify of the host is known. */
2809
2810 if (tblock->filter_command)
2811 {
2812 transport_filter_timeout = tblock->filter_timeout;
2813
2814 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2815 yield ERROR. */
2816
2817 if (!transport_set_up_command(&transport_filter_argv,
2818 tblock->filter_command, TRUE, DEFER, addrlist,
2819 string_sprintf("%.50s transport", tblock->name), NULL))
2820 {
2821 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2822 FALSE);
2823 yield = ERROR;
2824 goto SEND_QUIT;
2825 }
2826
2827 if ( transport_filter_argv
2828 && *transport_filter_argv
2829 && **transport_filter_argv
2830 && sx.peer_offered & OPTION_CHUNKING
2831 )
2832 {
2833 sx.peer_offered &= ~OPTION_CHUNKING;
2834 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2835 }
2836 }
2837
2838 sx.first_addr = addrlist;
2839
2840 /* For messages that have more than the maximum number of envelope recipients,
2841 we want to send several transactions down the same SMTP connection. (See
2842 comments in deliver.c as to how this reconciles, heuristically, with
2843 remote_max_parallel.) This optimization was added to Exim after the following
2844 code was already working. The simplest way to put it in without disturbing the
2845 code was to use a goto to jump back to this point when there is another
2846 transaction to handle. */
2847
2848 SEND_MESSAGE:
2849 sx.from_addr = return_path;
2850 sx.sync_addr = sx.first_addr;
2851 sx.ok = FALSE;
2852 sx.send_rset = TRUE;
2853 sx.completed_addr = FALSE;
2854
2855
2856 /* If we are a continued-connection-after-verify the MAIL and RCPT
2857 commands were already sent; do not re-send but do mark the addrs as
2858 having been accepted up to RCPT stage. A traditional cont-conn
2859 always has a sequence number greater than one. */
2860
2861 if (continue_hostname && continue_sequence == 1)
2862 {
2863 address_item * addr;
2864
2865 sx.peer_offered = smtp_peer_options;
2866 sx.pending_MAIL = FALSE;
2867 sx.ok = TRUE;
2868 sx.next_addr = NULL;
2869
2870 for (addr = addrlist; addr; addr = addr->next)
2871 addr->transport_return = PENDING_OK;
2872 }
2873 else
2874 {
2875 /* Initiate a message transfer. */
2876
2877 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
2878 {
2879 case 0: break;
2880 case -1: case -2: goto RESPONSE_FAILED;
2881 case -3: goto END_OFF;
2882 case -4: goto SEND_QUIT;
2883 default: goto SEND_FAILED;
2884 }
2885
2886 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2887 permanently or temporarily. We should have flushed and synced after the last
2888 RCPT. */
2889
2890 if (mua_wrapper)
2891 {
2892 address_item * a;
2893 unsigned cnt;
2894
2895 for (a = sx.first_addr, cnt = 0; a && cnt < sx.max_rcpt; a = a->next, cnt++)
2896 if (a->transport_return != PENDING_OK)
2897 {
2898 /*XXX could we find a better errno than 0 here? */
2899 set_errno_nohost(addrlist, 0, a->message, FAIL,
2900 testflag(a, af_pass_message));
2901 sx.ok = FALSE;
2902 break;
2903 }
2904 }
2905 }
2906
2907 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2908 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2909 have a good recipient buffered up if we are pipelining. We don't want to waste
2910 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2911 are pipelining. The responses are all handled by sync_responses().
2912 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2913 to send is. */
2914
2915 if ( !(sx.peer_offered & OPTION_CHUNKING)
2916 && (sx.ok || (pipelining_active && !mua_wrapper)))
2917 {
2918 int count = smtp_write_command(&sx.outblock, SCMD_FLUSH, "DATA\r\n");
2919
2920 if (count < 0) goto SEND_FAILED;
2921 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
2922 {
2923 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2924 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2925 break;
2926
2927 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2928 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2929 case 0: break; /* No 2xx or 5xx, but no probs */
2930
2931 case -1: goto END_OFF; /* Timeout on RCPT */
2932 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2933 }
2934 pipelining_active = FALSE;
2935 data_command = string_copy(big_buffer); /* Save for later error message */
2936 }
2937
2938 /* If there were no good recipients (but otherwise there have been no
2939 problems), just set ok TRUE, since we have handled address-specific errors
2940 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2941 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2942 well as body. Set the appropriate timeout value to be used for each chunk.
2943 (Haven't been able to make it work using select() for writing yet.) */
2944
2945 if (!(sx.peer_offered & OPTION_CHUNKING) && !sx.ok)
2946 {
2947 /* Save the first address of the next batch. */
2948 sx.first_addr = sx.next_addr;
2949
2950 sx.ok = TRUE;
2951 }
2952 else
2953 {
2954 transport_ctx tctx = {
2955 {sx.inblock.sock},
2956 tblock,
2957 addrlist,
2958 US".", US"..", /* Escaping strings */
2959 topt_use_crlf | topt_escape_headers
2960 | (tblock->body_only ? topt_no_headers : 0)
2961 | (tblock->headers_only ? topt_no_body : 0)
2962 | (tblock->return_path_add ? topt_add_return_path : 0)
2963 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2964 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2965 };
2966
2967 /* If using CHUNKING we need a callback from the generic transport
2968 support to us, for the sending of BDAT smtp commands and the reaping
2969 of responses. The callback needs a whole bunch of state so set up
2970 a transport-context structure to be passed around. */
2971
2972 if (sx.peer_offered & OPTION_CHUNKING)
2973 {
2974 tctx.check_string = tctx.escape_string = NULL;
2975 tctx.options |= topt_use_bdat;
2976 tctx.chunk_cb = smtp_chunk_cmd_callback;
2977 sx.pending_BDAT = FALSE;
2978 sx.good_RCPT = sx.ok;
2979 sx.cmd_count = 0;
2980 tctx.smtp_context = &sx;
2981 }
2982 else
2983 tctx.options |= topt_end_dot;
2984
2985 /* Save the first address of the next batch. */
2986 sx.first_addr = sx.next_addr;
2987
2988 /* Responses from CHUNKING commands go in buffer. Otherwise,
2989 there has not been a response. */
2990
2991 sx.buffer[0] = 0;
2992
2993 sigalrm_seen = FALSE;
2994 transport_write_timeout = sx.ob->data_timeout;
2995 smtp_command = US"sending data block"; /* For error messages */
2996 DEBUG(D_transport|D_v)
2997 if (sx.peer_offered & OPTION_CHUNKING)
2998 debug_printf(" will write message using CHUNKING\n");
2999 else
3000 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3001 transport_count = 0;
3002
3003 #ifndef DISABLE_DKIM
3004 dkim_exim_sign_init();
3005 # ifdef EXPERIMENTAL_ARC
3006 {
3007 uschar * s = sx.ob->arc_sign;
3008 if (s)
3009 {
3010 if (!(sx.ob->dkim.arc_signspec = s = expand_string(s)))
3011 {
3012 if (!expand_string_forcedfail)
3013 {
3014 message = US"failed to expand arc_sign";
3015 sx.ok = FALSE;
3016 goto SEND_FAILED;
3017 }
3018 }
3019 else if (*s)
3020 {
3021 /* Ask dkim code to hash the body for ARC */
3022 (void) arc_ams_setup_sign_bodyhash();
3023 sx.ob->dkim.force_bodyhash = TRUE;
3024 }
3025 }
3026 }
3027 # endif
3028 sx.ok = dkim_transport_write_message(&tctx, &sx.ob->dkim, CUSS &message);
3029 #else
3030 sx.ok = transport_write_message(&tctx, 0);
3031 #endif
3032
3033 /* transport_write_message() uses write() because it is called from other
3034 places to write to non-sockets. This means that under some OS (e.g. Solaris)
3035 it can exit with "Broken pipe" as its error. This really means that the
3036 socket got closed at the far end. */
3037
3038 transport_write_timeout = 0; /* for subsequent transports */
3039
3040 /* Failure can either be some kind of I/O disaster (including timeout),
3041 or the failure of a transport filter or the expansion of added headers.
3042 Or, when CHUNKING, it can be a protocol-detected failure. */
3043
3044 if (!sx.ok)
3045 if (message) goto SEND_FAILED;
3046 else goto RESPONSE_FAILED;
3047
3048 /* We used to send the terminating "." explicitly here, but because of
3049 buffering effects at both ends of TCP/IP connections, you don't gain
3050 anything by keeping it separate, so it might as well go in the final
3051 data buffer for efficiency. This is now done by setting the topt_end_dot
3052 flag above. */
3053
3054 smtp_command = US"end of data";
3055
3056 if (sx.peer_offered & OPTION_CHUNKING && sx.cmd_count > 1)
3057 {
3058 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
3059 switch(sync_responses(&sx, sx.cmd_count-1, 0))
3060 {
3061 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3062 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3063 break;
3064
3065 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3066 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3067 case 0: break; /* No 2xx or 5xx, but no probs */
3068
3069 case -1: goto END_OFF; /* Timeout on RCPT */
3070 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3071 }
3072 }
3073
3074 #ifndef DISABLE_PRDR
3075 /* For PRDR we optionally get a partial-responses warning
3076 * followed by the individual responses, before going on with
3077 * the overall response. If we don't get the warning then deal
3078 * with per non-PRDR. */
3079 if(sx.prdr_active)
3080 {
3081 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '3',
3082 sx.ob->final_timeout);
3083 if (!sx.ok && errno == 0) switch(sx.buffer[0])
3084 {
3085 case '2': sx.prdr_active = FALSE;
3086 sx.ok = TRUE;
3087 break;
3088 case '4': errno = ERRNO_DATA4XX;
3089 addrlist->more_errno |=
3090 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3091 break;
3092 }
3093 }
3094 else
3095 #endif
3096
3097 /* For non-PRDR SMTP, we now read a single response that applies to the
3098 whole message. If it is OK, then all the addresses have been delivered. */
3099
3100 if (!sx.lmtp)
3101 {
3102 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3103 sx.ob->final_timeout);
3104 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
3105 {
3106 errno = ERRNO_DATA4XX;
3107 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3108 }
3109 }
3110
3111 /* For LMTP, we get back a response for every RCPT command that we sent;
3112 some may be accepted and some rejected. For those that get a response, their
3113 status is fixed; any that are accepted have been handed over, even if later
3114 responses crash - at least, that's how I read RFC 2033.
3115
3116 If all went well, mark the recipient addresses as completed, record which
3117 host/IPaddress they were delivered to, and cut out RSET when sending another
3118 message down the same channel. Write the completed addresses to the journal
3119 now so that they are recorded in case there is a crash of hardware or
3120 software before the spool gets updated. Also record the final SMTP
3121 confirmation if needed (for SMTP only). */
3122
3123 if (sx.ok)
3124 {
3125 int flag = '=';
3126 struct timeval delivery_time;
3127 int len;
3128 uschar * conf = NULL;
3129
3130 timesince(&delivery_time, &start_delivery_time);
3131 sx.send_rset = FALSE;
3132 pipelining_active = FALSE;
3133
3134 /* Set up confirmation if needed - applies only to SMTP */
3135
3136 if (
3137 #ifdef DISABLE_EVENT
3138 LOGGING(smtp_confirmation) &&
3139 #endif
3140 !sx.lmtp
3141 )
3142 {
3143 const uschar *s = string_printing(sx.buffer);
3144 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3145 conf = (s == sx.buffer)? US string_copy(s) : US s;
3146 }
3147
3148 /* Process all transported addresses - for LMTP or PRDR, read a status for
3149 each one. */
3150
3151 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3152 {
3153 if (addr->transport_return != PENDING_OK) continue;
3154
3155 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3156 remaining addresses. Otherwise, it's a return code for just the one
3157 address. For temporary errors, add a retry item for the address so that
3158 it doesn't get tried again too soon. */
3159
3160 #ifndef DISABLE_PRDR
3161 if (sx.lmtp || sx.prdr_active)
3162 #else
3163 if (sx.lmtp)
3164 #endif
3165 {
3166 if (!smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3167 sx.ob->final_timeout))
3168 {
3169 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3170 addr->message = string_sprintf(
3171 #ifndef DISABLE_PRDR
3172 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3173 #else
3174 "LMTP error after %s: %s",
3175 #endif
3176 data_command, string_printing(sx.buffer));
3177 setflag(addr, af_pass_message); /* Allow message to go to user */
3178 if (sx.buffer[0] == '5')
3179 addr->transport_return = FAIL;
3180 else
3181 {
3182 errno = ERRNO_DATA4XX;
3183 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3184 addr->transport_return = DEFER;
3185 #ifndef DISABLE_PRDR
3186 if (!sx.prdr_active)
3187 #endif
3188 retry_add_item(addr, addr->address_retry_key, 0);
3189 }
3190 continue;
3191 }
3192 sx.completed_addr = TRUE; /* NOW we can set this flag */
3193 if (LOGGING(smtp_confirmation))
3194 {
3195 const uschar *s = string_printing(sx.buffer);
3196 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3197 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3198 }
3199 }
3200
3201 /* SMTP, or success return from LMTP for this address. Pass back the
3202 actual host that was used. */
3203
3204 addr->transport_return = OK;
3205 addr->more_errno = delivery_time.tv_sec;
3206 addr->delivery_usec = delivery_time.tv_usec;
3207 addr->host_used = host;
3208 addr->special_action = flag;
3209 addr->message = conf;
3210 #ifndef DISABLE_PRDR
3211 if (sx.prdr_active) setflag(addr, af_prdr_used);
3212 #endif
3213 if (sx.peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
3214 flag = '-';
3215
3216 #ifndef DISABLE_PRDR
3217 if (!sx.prdr_active)
3218 #endif
3219 {
3220 /* Update the journal. For homonymic addresses, use the base address plus
3221 the transport name. See lots of comments in deliver.c about the reasons
3222 for the complications when homonyms are involved. Just carry on after
3223 write error, as it may prove possible to update the spool file later. */
3224
3225 if (testflag(addr, af_homonym))
3226 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3227 else
3228 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3229
3230 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3231 len = Ustrlen(CS sx.buffer);
3232 if (write(journal_fd, sx.buffer, len) != len)
3233 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3234 "%s: %s", sx.buffer, strerror(errno));
3235 }
3236 }
3237
3238 #ifndef DISABLE_PRDR
3239 if (sx.prdr_active)
3240 {
3241 const uschar * overall_message;
3242
3243 /* PRDR - get the final, overall response. For any non-success
3244 upgrade all the address statuses. */
3245
3246 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3247 sx.ob->final_timeout);
3248 if (!sx.ok)
3249 {
3250 if(errno == 0 && sx.buffer[0] == '4')
3251 {
3252 errno = ERRNO_DATA4XX;
3253 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3254 }
3255 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3256 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3257 addr->transport_return = PENDING_OK; /* allow set_errno action */
3258 goto RESPONSE_FAILED;
3259 }
3260
3261 /* Append the overall response to the individual PRDR response for logging
3262 and update the journal, or setup retry. */
3263
3264 overall_message = string_printing(sx.buffer);
3265 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3266 if (addr->transport_return == OK)
3267 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
3268
3269 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3270 if (addr->transport_return == OK)
3271 {
3272 if (testflag(addr, af_homonym))
3273 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3274 else
3275 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3276
3277 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3278 len = Ustrlen(CS sx.buffer);
3279 if (write(journal_fd, sx.buffer, len) != len)
3280 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3281 "%s: %s", sx.buffer, strerror(errno));
3282 }
3283 else if (addr->transport_return == DEFER)
3284 retry_add_item(addr, addr->address_retry_key, -2);
3285 }
3286 #endif
3287
3288 /* Ensure the journal file is pushed out to disk. */
3289
3290 if (EXIMfsync(journal_fd) < 0)
3291 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3292 strerror(errno));
3293 }
3294 }
3295
3296
3297 /* Handle general (not specific to one address) failures here. The value of ok
3298 is used to skip over this code on the falling through case. A timeout causes a
3299 deferral. Other errors may defer or fail according to the response code, and
3300 may set up a special errno value, e.g. after connection chopped, which is
3301 assumed if errno == 0 and there is no text in the buffer. If control reaches
3302 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3303 the problem is not related to this specific message. */
3304
3305 if (!sx.ok)
3306 {
3307 int code, set_rc;
3308 uschar * set_message;
3309
3310 RESPONSE_FAILED:
3311 {
3312 save_errno = errno;
3313 message = NULL;
3314 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3315 sx.buffer, &code, &message, &pass_message);
3316 goto FAILED;
3317 }
3318
3319 SEND_FAILED:
3320 {
3321 save_errno = errno;
3322 code = '4';
3323 message = string_sprintf("send() to %s [%s] failed: %s",
3324 host->name, host->address, message ? message : US strerror(save_errno));
3325 sx.send_quit = FALSE;
3326 goto FAILED;
3327 }
3328
3329 FAILED:
3330 {
3331 BOOL message_error;
3332
3333 sx.ok = FALSE; /* For when reached by GOTO */
3334 set_message = message;
3335
3336 /* We want to handle timeouts after MAIL or "." and loss of connection after
3337 "." specially. They can indicate a problem with the sender address or with
3338 the contents of the message rather than a real error on the connection. These
3339 cases are treated in the same way as a 4xx response. This next bit of code
3340 does the classification. */
3341
3342 switch(save_errno)
3343 {
3344 case 0:
3345 case ERRNO_MAIL4XX:
3346 case ERRNO_DATA4XX:
3347 message_error = TRUE;
3348 break;
3349
3350 case ETIMEDOUT:
3351 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
3352 Ustrncmp(smtp_command,"end ",4) == 0;
3353 break;
3354
3355 case ERRNO_SMTPCLOSED:
3356 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
3357 break;
3358
3359 default:
3360 message_error = FALSE;
3361 break;
3362 }
3363
3364 /* Handle the cases that are treated as message errors. These are:
3365
3366 (a) negative response or timeout after MAIL
3367 (b) negative response after DATA
3368 (c) negative response or timeout or dropped connection after "."
3369 (d) utf8 support required and not offered
3370
3371 It won't be a negative response or timeout after RCPT, as that is dealt
3372 with separately above. The action in all cases is to set an appropriate
3373 error code for all the addresses, but to leave yield set to OK because the
3374 host itself has not failed. Of course, it might in practice have failed
3375 when we've had a timeout, but if so, we'll discover that at the next
3376 delivery attempt. For a temporary error, set the message_defer flag, and
3377 write to the logs for information if this is not the last host. The error
3378 for the last host will be logged as part of the address's log line. */
3379
3380 if (message_error)
3381 {
3382 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
3383
3384 /* If there's an errno, the message contains just the identity of
3385 the host. */
3386
3387 if (code == '5')
3388 set_rc = FAIL;
3389 else /* Anything other than 5 is treated as temporary */
3390 {
3391 set_rc = DEFER;
3392 if (save_errno > 0)
3393 message = US string_sprintf("%s: %s", message, strerror(save_errno));
3394
3395 write_logs(host, message, sx.first_addr ? sx.first_addr->basic_errno : 0);
3396
3397 *message_defer = TRUE;
3398 }
3399 }
3400
3401 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
3402 ".", or some other transportation error. We defer all addresses and yield
3403 DEFER, except for the case of failed add_headers expansion, or a transport
3404 filter failure, when the yield should be ERROR, to stop it trying other
3405 hosts. */
3406
3407 else
3408 {
3409 set_rc = DEFER;
3410 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
3411 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3412 }
3413 }
3414
3415 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3416 #ifdef EXPERIMENTAL_DSN_INFO
3417 , sx.smtp_greeting, sx.helo_response
3418 #endif
3419 );
3420 }
3421
3422
3423 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3424 SMTP session tidily. However, if there were too many addresses to send in one
3425 message (indicated by first_addr being non-NULL) we want to carry on with the
3426 rest of them. Also, it is desirable to send more than one message down the SMTP
3427 connection if there are several waiting, provided we haven't already sent so
3428 many as to hit the configured limit. The function transport_check_waiting looks
3429 for a waiting message and returns its id. Then transport_pass_socket tries to
3430 set up a continued delivery by passing the socket on to another process. The
3431 variable send_rset is FALSE if a message has just been successfully transfered.
3432
3433 If we are already sending down a continued channel, there may be further
3434 addresses not yet delivered that are aimed at the same host, but which have not
3435 been passed in this run of the transport. In this case, continue_more will be
3436 true, and all we should do is send RSET if necessary, and return, leaving the
3437 channel open.
3438
3439 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3440 do not want to continue with other messages down the same channel, because that
3441 can lead to looping between two or more messages, all with the same,
3442 temporarily failing address(es). [The retry information isn't updated yet, so
3443 new processes keep on trying.] We probably also don't want to try more of this
3444 message's addresses either.
3445
3446 If we have started a TLS session, we have to end it before passing the
3447 connection to a new process. However, not all servers can handle this (Exim
3448 can), so we do not pass such a connection on if the host matches
3449 hosts_nopass_tls. */
3450
3451 DEBUG(D_transport)
3452 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3453 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
3454 sx.send_rset, continue_more, yield, sx.first_addr ? "not " : "");
3455
3456 if (sx.completed_addr && sx.ok && sx.send_quit)
3457 {
3458 BOOL more;
3459 smtp_compare_t t_compare;
3460
3461 t_compare.tblock = tblock;
3462 t_compare.current_sender_address = sender_address;
3463
3464 if ( sx.first_addr != NULL
3465 || continue_more
3466 || (
3467 #ifdef SUPPORT_TLS
3468 ( tls_out.active < 0 && !continue_proxy_cipher
3469 || verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
3470 )
3471 &&
3472 #endif
3473 transport_check_waiting(tblock->name, host->name,
3474 tblock->connection_max_messages, new_message_id, &more,
3475 (oicf)smtp_are_same_identities, (void*)&t_compare)
3476 ) )
3477 {
3478 uschar *msg;
3479 BOOL pass_message;
3480
3481 if (sx.send_rset)
3482 if (! (sx.ok = smtp_write_command(&sx.outblock, SCMD_FLUSH, "RSET\r\n") >= 0))
3483 {
3484 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3485 host->address, strerror(errno));
3486 sx.send_quit = FALSE;
3487 }
3488 else if (! (sx.ok = smtp_read_response(&sx.inblock, sx.buffer,
3489 sizeof(sx.buffer), '2', sx.ob->command_timeout)))
3490 {
3491 int code;
3492 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
3493 &pass_message);
3494 if (!sx.send_quit)
3495 {
3496 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3497 host->name, host->address, msg);
3498 }
3499 }
3500
3501 /* Either RSET was not needed, or it succeeded */
3502
3503 if (sx.ok)
3504 {
3505 int pfd[2];
3506 int socket_fd = sx.inblock.sock;
3507
3508
3509 if (sx.first_addr != NULL) /* More addresses still to be sent */
3510 { /* in this run of the transport */
3511 continue_sequence++; /* Causes * in logging */
3512 goto SEND_MESSAGE;
3513 }
3514
3515 /* Unless caller said it already has more messages listed for this host,
3516 pass the connection on to a new Exim process (below, the call to
3517 transport_pass_socket). If the caller has more ready, just return with
3518 the connection still open. */
3519
3520 #ifdef SUPPORT_TLS
3521 if (tls_out.active >= 0)
3522 if ( continue_more
3523 || verify_check_given_host(&sx.ob->hosts_noproxy_tls, host) == OK)
3524 {
3525 /* Before passing the socket on, or returning to caller with it still
3526 open, we must shut down TLS. Not all MTAs allow for the continuation
3527 of the SMTP session when TLS is shut down. We test for this by sending
3528 a new EHLO. If we don't get a good response, we don't attempt to pass
3529 the socket on. */
3530
3531 tls_close(FALSE, TLS_SHUTDOWN_WAIT);
3532 smtp_peer_options = smtp_peer_options_wrap;
3533 sx.ok = !sx.smtps
3534 && smtp_write_command(&sx.outblock, SCMD_FLUSH,
3535 "EHLO %s\r\n", sx.helo_data) >= 0
3536 && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
3537 '2', sx.ob->command_timeout);
3538
3539 if (sx.ok && continue_more)
3540 return yield; /* More addresses for another run */
3541 }
3542 else
3543 {
3544 /* Set up a pipe for proxying TLS for the new transport process */
3545
3546 smtp_peer_options |= OPTION_TLS;
3547 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
3548 socket_fd = pfd[1];
3549 else
3550 set_errno(sx.first_addr, errno, US"internal allocation problem",
3551 DEFER, FALSE, host
3552 # ifdef EXPERIMENTAL_DSN_INFO
3553 , sx.smtp_greeting, sx.helo_response
3554 # endif
3555 );
3556 }
3557 else
3558 #endif
3559 if (continue_more)
3560 return yield; /* More addresses for another run */
3561
3562 /* If the socket is successfully passed, we mustn't send QUIT (or
3563 indeed anything!) from here. */
3564
3565 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3566 propagate it from the initial
3567 */
3568 if (sx.ok && transport_pass_socket(tblock->name, host->name,
3569 host->address, new_message_id, socket_fd))
3570 {
3571 sx.send_quit = FALSE;
3572
3573 /* We have passed the client socket to a fresh transport process.
3574 If TLS is still active, we need to proxy it for the transport we
3575 just passed the baton to. Fork a child to to do it, and return to
3576 get logging done asap. Which way to place the work makes assumptions
3577 about post-fork prioritisation which may not hold on all platforms. */
3578 #ifdef SUPPORT_TLS
3579 if (tls_out.active >= 0)
3580 {
3581 int pid = fork();
3582 if (pid == 0) /* child; fork again to disconnect totally */
3583 {
3584 if (running_in_test_harness) millisleep(100); /* let parent debug out */
3585 /* does not return */
3586 smtp_proxy_tls(sx.buffer, sizeof(sx.buffer), pfd,
3587 sx.ob->command_timeout);
3588 }
3589
3590 if (pid > 0) /* parent */
3591 {
3592 DEBUG(D_transport) debug_printf("proxy-proc inter-pid %d\n", pid);
3593 close(pfd[0]);
3594 /* tidy the inter-proc to disconn the proxy proc */
3595 waitpid(pid, NULL, 0);
3596 tls_close(FALSE, TLS_NO_SHUTDOWN);
3597 (void)close(sx.inblock.sock);
3598 continue_transport = NULL;
3599 continue_hostname = NULL;
3600 return yield;
3601 }
3602 log_write(0, LOG_PANIC_DIE, "fork failed");
3603 }
3604 #endif
3605 }
3606 }
3607
3608 /* If RSET failed and there are addresses left, they get deferred. */
3609 else
3610 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
3611 #ifdef EXPERIMENTAL_DSN_INFO
3612 , sx.smtp_greeting, sx.helo_response
3613 #endif
3614 );
3615 }
3616 }
3617
3618 /* End off tidily with QUIT unless the connection has died or the socket has
3619 been passed to another process. There has been discussion on the net about what
3620 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3621 to wait for a response, but on the other hand, there isn't anything one can do
3622 with an error response, other than log it. Exim used to do that. However,
3623 further discussion suggested that it is positively advantageous not to wait for
3624 the response, but to close the session immediately. This is supposed to move
3625 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3626 load from the server. (Hosts that are both servers and clients may not see much
3627 difference, of course.) Further discussion indicated that this was safe to do
3628 on Unix systems which have decent implementations of TCP/IP that leave the
3629 connection around for a while (TIME_WAIT) after the application has gone away.
3630 This enables the response sent by the server to be properly ACKed rather than
3631 timed out, as can happen on broken TCP/IP implementations on other OS.
3632
3633 This change is being made on 31-Jul-98. After over a year of trouble-free
3634 operation, the old commented-out code was removed on 17-Sep-99. */
3635
3636 SEND_QUIT:
3637 if (sx.send_quit) (void)smtp_write_command(&sx.outblock, SCMD_FLUSH, "QUIT\r\n");
3638
3639 END_OFF:
3640
3641 #ifdef SUPPORT_TLS
3642 tls_close(FALSE, TLS_SHUTDOWN_NOWAIT);
3643 #endif
3644
3645 /* Close the socket, and return the appropriate value, first setting
3646 works because the NULL setting is passed back to the calling process, and
3647 remote_max_parallel is forced to 1 when delivering over an existing connection,
3648
3649 If all went well and continue_more is set, we shouldn't actually get here if
3650 there are further addresses, as the return above will be taken. However,
3651 writing RSET might have failed, or there may be other addresses whose hosts are
3652 specified in the transports, and therefore not visible at top level, in which
3653 case continue_more won't get set. */
3654
3655 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3656 if (sx.send_quit)
3657 {
3658 shutdown(sx.outblock.sock, SHUT_WR);
3659 if (fcntl(sx.inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3660 for (rc = 16; read(sx.inblock.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && rc > 0;)
3661 rc--; /* drain socket */
3662 }
3663 (void)close(sx.inblock.sock);
3664
3665 #ifndef DISABLE_EVENT
3666 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3667 #endif
3668
3669 continue_transport = NULL;
3670 continue_hostname = NULL;
3671 return yield;
3672 }
3673
3674
3675
3676
3677 /*************************************************
3678 * Closedown entry point *
3679 *************************************************/
3680
3681 /* This function is called when exim is passed an open smtp channel
3682 from another incarnation, but the message which it has been asked
3683 to deliver no longer exists. The channel is on stdin.
3684
3685 We might do fancy things like looking for another message to send down
3686 the channel, but if the one we sought has gone, it has probably been
3687 delivered by some other process that itself will seek further messages,
3688 so just close down our connection.
3689
3690 Argument: pointer to the transport instance block
3691 Returns: nothing
3692 */
3693
3694 void
3695 smtp_transport_closedown(transport_instance *tblock)
3696 {
3697 smtp_transport_options_block *ob =
3698 (smtp_transport_options_block *)tblock->options_block;
3699 smtp_inblock inblock;
3700 smtp_outblock outblock;
3701 uschar buffer[256];
3702 uschar inbuffer[4096];
3703 uschar outbuffer[16];
3704
3705 inblock.sock = fileno(stdin);
3706 inblock.buffer = inbuffer;
3707 inblock.buffersize = sizeof(inbuffer);
3708 inblock.ptr = inbuffer;
3709 inblock.ptrend = inbuffer;
3710
3711 outblock.sock = inblock.sock;
3712 outblock.buffersize = sizeof(outbuffer);
3713 outblock.buffer = outbuffer;
3714 outblock.ptr = outbuffer;
3715 outblock.cmd_count = 0;
3716 outblock.authenticating = FALSE;
3717
3718 (void)smtp_write_command(&outblock, SCMD_FLUSH, "QUIT\r\n");
3719 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3720 ob->command_timeout);
3721 (void)close(inblock.sock);
3722 }
3723
3724
3725
3726 /*************************************************
3727 * Prepare addresses for delivery *
3728 *************************************************/
3729
3730 /* This function is called to flush out error settings from previous delivery
3731 attempts to other hosts. It also records whether we got here via an MX record
3732 or not in the more_errno field of the address. We are interested only in
3733 addresses that are still marked DEFER - others may have got delivered to a
3734 previously considered IP address. Set their status to PENDING_DEFER to indicate
3735 which ones are relevant this time.
3736
3737 Arguments:
3738 addrlist the list of addresses
3739 host the host we are delivering to
3740
3741 Returns: the first address for this delivery
3742 */
3743
3744 static address_item *
3745 prepare_addresses(address_item *addrlist, host_item *host)
3746 {
3747 address_item *first_addr = NULL;
3748 address_item *addr;
3749 for (addr = addrlist; addr; addr = addr->next)
3750 if (addr->transport_return == DEFER)
3751 {
3752 if (!first_addr) first_addr = addr;
3753 addr->transport_return = PENDING_DEFER;
3754 addr->basic_errno = 0;
3755 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3756 addr->message = NULL;
3757 #ifdef SUPPORT_TLS
3758 addr->cipher = NULL;
3759 addr->ourcert = NULL;
3760 addr->peercert = NULL;
3761 addr->peerdn = NULL;
3762 addr->ocsp = OCSP_NOT_REQ;
3763 #endif
3764 #ifdef EXPERIMENTAL_DSN_INFO
3765 addr->smtp_greeting = NULL;
3766 addr->helo_response = NULL;
3767 #endif
3768 }
3769 return first_addr;
3770 }
3771
3772
3773
3774 /*************************************************
3775 * Main entry point *
3776 *************************************************/
3777
3778 /* See local README for interface details. As this is a remote transport, it is
3779 given a chain of addresses to be delivered in one connection, if possible. It
3780 always returns TRUE, indicating that each address has its own independent
3781 status set, except if there is a setting up problem, in which case it returns
3782 FALSE. */
3783
3784 BOOL
3785 smtp_transport_entry(
3786 transport_instance *tblock, /* data for this instantiation */
3787 address_item *addrlist) /* addresses we are working on */
3788 {
3789 int cutoff_retry;
3790 int defport;
3791 int hosts_defer = 0;
3792 int hosts_fail = 0;
3793 int hosts_looked_up = 0;
3794 int hosts_retry = 0;
3795 int hosts_serial = 0;
3796 int hosts_total = 0;
3797 int total_hosts_tried = 0;
3798 address_item *addr;
3799 BOOL expired = TRUE;
3800 uschar *expanded_hosts = NULL;
3801 uschar *pistring;
3802 uschar *tid = string_sprintf("%s transport", tblock->name);
3803 smtp_transport_options_block *ob =
3804 (smtp_transport_options_block *)(tblock->options_block);
3805 host_item *hostlist = addrlist->host_list;
3806 host_item *host;
3807
3808 DEBUG(D_transport)
3809 {
3810 debug_printf("%s transport entered\n", tblock->name);
3811 for (addr = addrlist; addr; addr = addr->next)
3812 debug_printf(" %s\n", addr->address);
3813 if (hostlist)
3814 {
3815 debug_printf("hostlist:\n");
3816 for (host = hostlist; host; host = host->next)
3817 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
3818 }
3819 if (continue_hostname)
3820 debug_printf("already connected to %s [%s] (on fd %d)\n",
3821 continue_hostname, continue_host_address,
3822 cutthrough.fd >= 0 ? cutthrough.fd : 0);
3823 }
3824
3825 /* Set the flag requesting that these hosts be added to the waiting
3826 database if the delivery fails temporarily or if we are running with
3827 queue_smtp or a 2-stage queue run. This gets unset for certain
3828 kinds of error, typically those that are specific to the message. */
3829
3830 update_waiting = TRUE;
3831
3832 /* If a host list is not defined for the addresses - they must all have the
3833 same one in order to be passed to a single transport - or if the transport has
3834 a host list with hosts_override set, use the host list supplied with the
3835 transport. It is an error for this not to exist. */
3836
3837 if (!hostlist || (ob->hosts_override && ob->hosts))
3838 {
3839 if (!ob->hosts)
3840 {
3841 addrlist->message = string_sprintf("%s transport called with no hosts set",
3842 tblock->name);
3843 addrlist->transport_return = PANIC;
3844 return FALSE; /* Only top address has status */
3845 }
3846
3847 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3848 ob->hosts);
3849
3850 /* If the transport's host list contains no '$' characters, and we are not
3851 randomizing, it is fixed and therefore a chain of hosts can be built once
3852 and for all, and remembered for subsequent use by other calls to this
3853 transport. If, on the other hand, the host list does contain '$', or we are
3854 randomizing its order, we have to rebuild it each time. In the fixed case,
3855 as the hosts string will never be used again, it doesn't matter that we
3856 replace all the : characters with zeros. */
3857
3858 if (!ob->hostlist)
3859 {
3860 uschar *s = ob->hosts;
3861
3862 if (Ustrchr(s, '$') != NULL)
3863 {
3864 if (!(expanded_hosts = expand_string(s)))
3865 {
3866 addrlist->message = string_sprintf("failed to expand list of hosts "
3867 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3868 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3869 return FALSE; /* Only top address has status */
3870 }
3871 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3872 "\"%s\"\n", s, expanded_hosts);
3873 s = expanded_hosts;
3874 }
3875 else
3876 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3877
3878 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3879
3880 /* Check that the expansion yielded something useful. */
3881 if (!hostlist)
3882 {
3883 addrlist->message =
3884 string_sprintf("%s transport has empty hosts setting", tblock->name);
3885 addrlist->transport_return = PANIC;
3886 return FALSE; /* Only top address has status */
3887 }
3888
3889 /* If there was no expansion of hosts, save the host list for
3890 next time. */
3891
3892 if (!expanded_hosts) ob->hostlist = hostlist;
3893 }
3894
3895 /* This is not the first time this transport has been run in this delivery;
3896 the host list was built previously. */
3897
3898 else
3899 hostlist = ob->hostlist;
3900 }
3901
3902 /* The host list was supplied with the address. If hosts_randomize is set, we
3903 must sort it into a random order if it did not come from MX records and has not
3904 already been randomized (but don't bother if continuing down an existing
3905 connection). */
3906
3907 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3908 {
3909 host_item *newlist = NULL;
3910 while (hostlist)
3911 {
3912 host_item *h = hostlist;
3913 hostlist = hostlist->next;
3914
3915 h->sort_key = random_number(100);
3916
3917 if (!newlist)
3918 {
3919 h->next = NULL;
3920 newlist = h;
3921 }
3922 else if (h->sort_key < newlist->sort_key)
3923 {
3924 h->next = newlist;
3925 newlist = h;
3926 }
3927 else
3928 {
3929 host_item *hh = newlist;
3930 while (hh->next)
3931 {
3932 if (h->sort_key < hh->next->sort_key) break;
3933 hh = hh->next;
3934 }
3935 h->next = hh->next;
3936 hh->next = h;
3937 }
3938 }
3939
3940 hostlist = addrlist->host_list = newlist;
3941 }
3942
3943 /* Sort out the default port. */
3944
3945 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
3946
3947 /* For each host-plus-IP-address on the list:
3948
3949 . If this is a continued delivery and the host isn't the one with the
3950 current connection, skip.
3951
3952 . If the status is unusable (i.e. previously failed or retry checked), skip.
3953
3954 . If no IP address set, get the address, either by turning the name into
3955 an address, calling gethostbyname if gethostbyname is on, or by calling
3956 the DNS. The DNS may yield multiple addresses, in which case insert the
3957 extra ones into the list.
3958
3959 . Get the retry data if not previously obtained for this address and set the
3960 field which remembers the state of this address. Skip if the retry time is
3961 not reached. If not, remember whether retry data was found. The retry string
3962 contains both the name and the IP address.
3963
3964 . Scan the list of addresses and mark those whose status is DEFER as
3965 PENDING_DEFER. These are the only ones that will be processed in this cycle
3966 of the hosts loop.
3967
3968 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3969 Some addresses may be successfully delivered, others may fail, and yet
3970 others may get temporary errors and so get marked DEFER.
3971
3972 . The return from the delivery attempt is OK if a connection was made and a
3973 valid SMTP dialogue was completed. Otherwise it is DEFER.
3974
3975 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3976
3977 . If fail to connect, or other defer state, add a retry item.
3978
3979 . If there are any addresses whose status is still DEFER, carry on to the
3980 next host/IPaddress, unless we have tried the number of hosts given
3981 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3982 there is some fancy logic for hosts_max_try that means its limit can be
3983 overstepped in some circumstances.
3984
3985 If we get to the end of the list, all hosts have deferred at least one address,
3986 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3987 delivery attempt to those hosts whose last try was before the arrival time of
3988 the current message. To cope with this, we have to go round the loop a second
3989 time. After that, set the status and error data for any addresses that haven't
3990 had it set already. */
3991
3992 for (cutoff_retry = 0;
3993 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3994 cutoff_retry++)
3995 {
3996 host_item *nexthost = NULL;
3997 int unexpired_hosts_tried = 0;
3998 BOOL continue_host_tried = FALSE;
3999
4000 retry_non_continued:
4001 for (host = hostlist;
4002 host
4003 && unexpired_hosts_tried < ob->hosts_max_try
4004 && total_hosts_tried < ob->hosts_max_try_hardlimit;
4005 host = nexthost)
4006 {
4007 int rc;
4008 int host_af;
4009 uschar *rs;
4010 BOOL host_is_expired = FALSE;
4011 BOOL message_defer = FALSE;
4012 BOOL some_deferred = FALSE;
4013 address_item *first_addr = NULL;
4014 uschar *interface = NULL;
4015 uschar *retry_host_key = NULL;
4016 uschar *retry_message_key = NULL;
4017 uschar *serialize_key = NULL;
4018
4019 /* Default next host is next host. :-) But this can vary if the
4020 hosts_max_try limit is hit (see below). It may also be reset if a host
4021 address is looked up here (in case the host was multihomed). */
4022
4023 nexthost = host->next;
4024
4025 /* If the address hasn't yet been obtained from the host name, look it up
4026 now, unless the host is already marked as unusable. If it is marked as
4027 unusable, it means that the router was unable to find its IP address (in
4028 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
4029 the lookup failed last time. We don't get this far if *all* MX records
4030 point to non-existent hosts; that is treated as a hard error.
4031
4032 We can just skip this host entirely. When the hosts came from the router,
4033 the address will timeout based on the other host(s); when the address is
4034 looked up below, there is an explicit retry record added.
4035
4036 Note that we mustn't skip unusable hosts if the address is not unset; they
4037 may be needed as expired hosts on the 2nd time round the cutoff loop. */
4038
4039 if (!host->address)
4040 {
4041 int new_port, flags;
4042 host_item *hh;
4043
4044 if (host->status >= hstatus_unusable)
4045 {
4046 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
4047 host->name);
4048 continue;
4049 }
4050
4051 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
4052
4053 /* The host name is permitted to have an attached port. Find it, and
4054 strip it from the name. Just remember it for now. */
4055
4056 new_port = host_item_get_port(host);
4057
4058 /* Count hosts looked up */
4059
4060 hosts_looked_up++;
4061
4062 /* Find by name if so configured, or if it's an IP address. We don't
4063 just copy the IP address, because we need the test-for-local to happen. */
4064
4065 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
4066 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
4067 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
4068
4069 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
4070 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
4071 else
4072 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
4073 &ob->dnssec, /* domains for request/require */
4074 NULL, NULL);
4075
4076 /* Update the host (and any additional blocks, resulting from
4077 multihoming) with a host-specific port, if any. */
4078
4079 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
4080
4081 /* Failure to find the host at this time (usually DNS temporary failure)
4082 is really a kind of routing failure rather than a transport failure.
4083 Therefore we add a retry item of the routing kind, not to stop us trying
4084 to look this name up here again, but to ensure the address gets timed
4085 out if the failures go on long enough. A complete failure at this point
4086 commonly points to a configuration error, but the best action is still
4087 to carry on for the next host. */
4088
4089 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
4090 {
4091 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
4092 expired = FALSE;
4093 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
4094 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
4095 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
4096 host->status = hstatus_unusable;
4097
4098 for (addr = addrlist; addr; addr = addr->next)
4099 {
4100 if (addr->transport_return != DEFER) continue;
4101 addr->basic_errno = ERRNO_UNKNOWNHOST;
4102 addr->message = string_sprintf(
4103 rc == HOST_FIND_SECURITY
4104 ? "lookup of IP address for %s was insecure"
4105 : "failed to lookup IP address for %s",
4106 host->name);
4107 }
4108 continue;
4109 }
4110
4111 /* If the host is actually the local host, we may have a problem, or
4112 there may be some cunning configuration going on. In the problem case,
4113 log things and give up. The default transport status is already DEFER. */
4114
4115 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
4116 {
4117 for (addr = addrlist; addr; addr = addr->next)
4118 {
4119 addr->basic_errno = 0;
4120 addr->message = string_sprintf("%s transport found host %s to be "
4121 "local", tblock->name, host->name);
4122 }
4123 goto END_TRANSPORT;
4124 }
4125 } /* End of block for IP address lookup */
4126
4127 /* If this is a continued delivery, we are interested only in the host
4128 which matches the name of the existing open channel. The check is put
4129 here after the local host lookup, in case the name gets expanded as a
4130 result of the lookup. Set expired FALSE, to save the outer loop executing
4131 twice. */
4132
4133 if (continue_hostname)
4134 if ( Ustrcmp(continue_hostname, host->name) != 0
4135 || Ustrcmp(continue_host_address, host->address) != 0
4136 )
4137 {
4138 expired = FALSE;
4139 continue; /* With next host */
4140 }
4141 else
4142 continue_host_tried = TRUE;
4143
4144 /* Reset the default next host in case a multihomed host whose addresses
4145 are not looked up till just above added to the host list. */
4146
4147 nexthost = host->next;
4148
4149 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
4150 domain is in queue_smtp_domains, we don't actually want to attempt any
4151 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
4152 there is a lookup defer in queue_smtp_domains, proceed as if the domain
4153 were not in it. We don't want to hold up all SMTP deliveries! Except when
4154 doing a two-stage queue run, don't do this if forcing. */
4155
4156 if ((!deliver_force || queue_2stage) && (queue_smtp ||
4157 match_isinlist(addrlist->domain,
4158 (const uschar **)&queue_smtp_domains, 0,
4159 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
4160 {
4161 expired = FALSE;
4162 for (addr = addrlist; addr; addr = addr->next)
4163 if (addr->transport_return == DEFER)
4164 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
4165 continue; /* With next host */
4166 }
4167
4168 /* Count hosts being considered - purely for an intelligent comment
4169 if none are usable. */
4170
4171 hosts_total++;
4172
4173 /* Set $host and $host address now in case they are needed for the
4174 interface expansion or the serialize_hosts check; they remain set if an
4175 actual delivery happens. */
4176
4177 deliver_host = host->name;
4178 deliver_host_address = host->address;
4179 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
4180 : host->dnssec == DS_NO ? US"no"
4181 : US"";
4182
4183 /* Set up a string for adding to the retry key if the port number is not
4184 the standard SMTP port. A host may have its own port setting that overrides
4185 the default. */
4186
4187 pistring = string_sprintf(":%d", host->port == PORT_NONE
4188 ? defport : host->port);
4189 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
4190
4191 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
4192 string is set, even if constant (as different transports can have different
4193 constant settings), we must add it to the key that is used for retries,
4194 because connections to the same host from a different interface should be
4195 treated separately. */
4196
4197 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
4198 if ((rs = ob->interface) && *rs)
4199 {
4200 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
4201 return FALSE;
4202 pistring = string_sprintf("%s/%s", pistring, interface);
4203 }
4204
4205 /* The first time round the outer loop, check the status of the host by
4206 inspecting the retry data. The second time round, we are interested only
4207 in expired hosts that haven't been tried since this message arrived. */
4208
4209 if (cutoff_retry == 0)
4210 {
4211 BOOL incl_ip;
4212 /* Ensure the status of the address is set by checking retry data if
4213 necessary. There may be host-specific retry data (applicable to all
4214 messages) and also data for retries of a specific message at this host.
4215 If either of these retry records are actually read, the keys used are
4216 returned to save recomputing them later. */
4217
4218 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4219 US"retry_include_ip_address", ob->retry_include_ip_address,
4220 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4221 continue; /* with next host */
4222
4223 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4224 incl_ip, &retry_host_key, &retry_message_key);
4225
4226 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4227 (host->address == NULL)? US"" : host->address, pistring,
4228 (host->status == hstatus_usable)? "usable" :
4229 (host->status == hstatus_unusable)? "unusable" :
4230 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
4231
4232 /* Skip this address if not usable at this time, noting if it wasn't
4233 actually expired, both locally and in the address. */
4234
4235 switch (host->status)
4236 {
4237 case hstatus_unusable:
4238 expired = FALSE;
4239 setflag(addrlist, af_retry_skipped);
4240 /* Fall through */
4241
4242 case hstatus_unusable_expired:
4243 switch (host->why)
4244 {
4245 case hwhy_retry: hosts_retry++; break;
4246 case hwhy_failed: hosts_fail++; break;
4247 case hwhy_insecure:
4248 case hwhy_deferred: hosts_defer++; break;
4249 }
4250
4251 /* If there was a retry message key, implying that previously there
4252 was a message-specific defer, we don't want to update the list of
4253 messages waiting for these hosts. */
4254
4255 if (retry_message_key) update_waiting = FALSE;
4256 continue; /* With the next host or IP address */
4257 }
4258 }
4259
4260 /* Second time round the loop: if the address is set but expired, and
4261 the message is newer than the last try, let it through. */
4262
4263 else
4264 {
4265 if ( !host->address
4266 || host->status != hstatus_unusable_expired
4267 || host->last_try > received_time.tv_sec)
4268 continue;
4269 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4270 host->name, host->address, pistring);
4271 host_is_expired = TRUE;
4272 }
4273
4274 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4275 it remains TRUE only if all hosts are expired and none are actually tried.
4276 */
4277
4278 expired = FALSE;
4279
4280 /* If this host is listed as one to which access must be serialized,
4281 see if another Exim process has a connection to it, and if so, skip
4282 this host. If not, update the database to record our connection to it
4283 and remember this for later deletion. Do not do any of this if we are
4284 sending the message down a pre-existing connection. */
4285
4286 if ( !continue_hostname
4287 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
4288 {
4289 serialize_key = string_sprintf("host-serialize-%s", host->name);
4290 if (!enq_start(serialize_key, 1))
4291 {
4292 DEBUG(D_transport)
4293 debug_printf("skipping host %s because another Exim process "
4294 "is connected to it\n", host->name);
4295 hosts_serial++;
4296 continue;
4297 }
4298 }
4299
4300 /* OK, we have an IP address that is not waiting for its retry time to
4301 arrive (it might be expired) OR (second time round the loop) we have an
4302 expired host that hasn't been tried since the message arrived. Have a go
4303 at delivering the message to it. First prepare the addresses by flushing
4304 out the result of previous attempts, and finding the first address that
4305 is still to be delivered. */
4306
4307 first_addr = prepare_addresses(addrlist, host);
4308
4309 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
4310 message_id, host->name, host->address, addrlist->address,
4311 addrlist->next ? ", ..." : "");
4312
4313 set_process_info("delivering %s to %s [%s] (%s%s)",
4314 message_id, host->name, host->address, addrlist->address,
4315 addrlist->next ? ", ..." : "");
4316
4317 /* This is not for real; don't do the delivery. If there are
4318 any remaining hosts, list them. */
4319
4320 if (dont_deliver)
4321 {
4322 host_item *host2;
4323 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
4324 for (addr = addrlist; addr; addr = addr->next)
4325 {
4326 addr->host_used = host;
4327 addr->special_action = '*';
4328 addr->message = US"delivery bypassed by -N option";
4329 }
4330 DEBUG(D_transport)
4331 {
4332 debug_printf("*** delivery by %s transport bypassed by -N option\n"
4333 "*** host and remaining hosts:\n", tblock->name);
4334 for (host2 = host; host2; host2 = host2->next)
4335 debug_printf(" %s [%s]\n", host2->name,
4336 host2->address ? host2->address : US"unset");
4337 }
4338 rc = OK;
4339 }
4340
4341 /* This is for real. If the host is expired, we don't count it for
4342 hosts_max_retry. This ensures that all hosts must expire before an address
4343 is timed out, unless hosts_max_try_hardlimit (which protects against
4344 lunatic DNS configurations) is reached.
4345
4346 If the host is not expired and we are about to hit the hosts_max_retry
4347 limit, check to see if there is a subsequent hosts with a different MX
4348 value. If so, make that the next host, and don't count this one. This is a
4349 heuristic to make sure that different MXs do get tried. With a normal kind
4350 of retry rule, they would get tried anyway when the earlier hosts were
4351 delayed, but if the domain has a "retry every time" type of rule - as is
4352 often used for the the very large ISPs, that won't happen. */
4353
4354 else
4355 {
4356 host_item * thost;
4357 /* Make a copy of the host if it is local to this invocation
4358 of the transport. */
4359
4360 if (expanded_hosts)
4361 {
4362 thost = store_get(sizeof(host_item));
4363 *thost = *host;
4364 thost->name = string_copy(host->name);
4365 thost->address = string_copy(host->address);
4366 }
4367 else
4368 thost = host;
4369
4370 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
4371 {
4372 host_item *h;
4373 DEBUG(D_transport)
4374 debug_printf("hosts_max_try limit reached with this host\n");
4375 for (h = host; h; h = h->next) if (h->mx != host->mx)
4376 {
4377 nexthost = h;
4378 unexpired_hosts_tried--;
4379 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
4380 "and will be tried\n");
4381 break;
4382 }
4383 }
4384
4385 /* Attempt the delivery. */
4386
4387 total_hosts_tried++;
4388 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
4389 &message_defer, FALSE);
4390
4391 /* Yield is one of:
4392 OK => connection made, each address contains its result;
4393 message_defer is set for message-specific defers (when all
4394 recipients are marked defer)
4395 DEFER => there was a non-message-specific delivery problem;
4396 ERROR => there was a problem setting up the arguments for a filter,
4397 or there was a problem with expanding added headers
4398 */
4399
4400 /* If the result is not OK, there was a non-message-specific problem.
4401 If the result is DEFER, we need to write to the logs saying what happened
4402 for this particular host, except in the case of authentication and TLS
4403 failures, where the log has already been written. If all hosts defer a
4404 general message is written at the end. */
4405
4406 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
4407 && first_addr->basic_errno != ERRNO_TLSFAILURE)
4408 write_logs(host, first_addr->message, first_addr->basic_errno);
4409
4410 #ifndef DISABLE_EVENT
4411 if (rc == DEFER)
4412 deferred_event_raise(first_addr, host);
4413 #endif
4414
4415 /* If STARTTLS was accepted, but there was a failure in setting up the
4416 TLS session (usually a certificate screwup), and the host is not in
4417 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
4418 TLS forcibly turned off. We have to start from scratch with a new SMTP
4419 connection. That's why the retry is done from here, not from within
4420 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
4421 session, so the in-clear transmission after those errors, if permitted,
4422 happens inside smtp_deliver().] */
4423
4424 #ifdef SUPPORT_TLS
4425 if ( rc == DEFER
4426 && first_addr->basic_errno == ERRNO_TLSFAILURE
4427 && ob->tls_tempfail_tryclear
4428 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
4429 )
4430 {
4431 log_write(0, LOG_MAIN,
4432 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
4433 first_addr->message, host->name, host->address);
4434 first_addr = prepare_addresses(addrlist, host);
4435 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
4436 &message_defer, TRUE);
4437 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
4438 write_logs(host, first_addr->message, first_addr->basic_errno);
4439 # ifndef DISABLE_EVENT
4440 if (rc == DEFER)
4441 deferred_event_raise(first_addr, host);
4442 # endif
4443 }
4444 #endif /*SUPPORT_TLS*/
4445 }
4446
4447 /* Delivery attempt finished */
4448
4449 rs = rc == OK ? US"OK"
4450 : rc == DEFER ? US"DEFER"
4451 : rc == ERROR ? US"ERROR"
4452 : US"?";
4453
4454 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
4455 message_id, host->name, host->address, addrlist->address,
4456 addrlist->next ? " (& others)" : "", rs);
4457
4458 /* Release serialization if set up */
4459
4460 if (serialize_key) enq_end(serialize_key);
4461
4462 /* If the result is DEFER, or if a host retry record is known to exist, we
4463 need to add an item to the retry chain for updating the retry database
4464 at the end of delivery. We only need to add the item to the top address,
4465 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
4466 for any other delivery attempts using the same address. (It is copied into
4467 the unusable tree at the outer level, so even if different address blocks
4468 contain the same address, it still won't get tried again.) */
4469
4470 if (rc == DEFER || retry_host_key)
4471 {
4472 int delete_flag = rc != DEFER ? rf_delete : 0;
4473 if (!retry_host_key)
4474 {
4475 BOOL incl_ip;
4476 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4477 US"retry_include_ip_address", ob->retry_include_ip_address,
4478 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4479 incl_ip = TRUE; /* error; use most-specific retry record */
4480
4481 retry_host_key = incl_ip
4482 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
4483 : string_sprintf("T:%S%s", host->name, pistring);
4484 }
4485
4486 /* If a delivery of another message over an existing SMTP connection
4487 yields DEFER, we do NOT set up retry data for the host. This covers the
4488 case when there are delays in routing the addresses in the second message
4489 that are so long that the server times out. This is alleviated by not
4490 routing addresses that previously had routing defers when handling an
4491 existing connection, but even so, this case may occur (e.g. if a
4492 previously happily routed address starts giving routing defers). If the
4493 host is genuinely down, another non-continued message delivery will
4494 notice it soon enough. */
4495
4496 if (delete_flag != 0 || !continue_hostname)
4497 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
4498
4499 /* We may have tried an expired host, if its retry time has come; ensure
4500 the status reflects the expiry for the benefit of any other addresses. */
4501
4502 if (rc == DEFER)
4503 {
4504 host->status = host_is_expired
4505 ? hstatus_unusable_expired : hstatus_unusable;
4506 host->why = hwhy_deferred;
4507 }
4508 }
4509
4510 /* If message_defer is set (host was OK, but every recipient got deferred
4511 because of some message-specific problem), or if that had happened
4512 previously so that a message retry key exists, add an appropriate item
4513 to the retry chain. Note that if there was a message defer but now there is
4514 a host defer, the message defer record gets deleted. That seems perfectly
4515 reasonable. Also, stop the message from being remembered as waiting
4516 for specific hosts. */
4517
4518 if (message_defer || retry_message_key)
4519 {
4520 int delete_flag = message_defer ? 0 : rf_delete;
4521 if (!retry_message_key)
4522 {
4523 BOOL incl_ip;
4524 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4525 US"retry_include_ip_address", ob->retry_include_ip_address,
4526 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4527 incl_ip = TRUE; /* error; use most-specific retry record */
4528
4529 retry_message_key = incl_ip
4530 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4531 message_id)
4532 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4533 }
4534 retry_add_item(addrlist, retry_message_key,
4535 rf_message | rf_host | delete_flag);
4536 update_waiting = FALSE;
4537 }
4538
4539 /* Any return other than DEFER (that is, OK or ERROR) means that the
4540 addresses have got their final statuses filled in for this host. In the OK
4541 case, see if any of them are deferred. */
4542
4543 if (rc == OK)
4544 for (addr = addrlist; addr; addr = addr->next)
4545 if (addr->transport_return == DEFER)
4546 {
4547 some_deferred = TRUE;
4548 break;
4549 }
4550
4551 /* If no addresses deferred or the result was ERROR, return. We do this for
4552 ERROR because a failing filter set-up or add_headers expansion is likely to
4553 fail for any host we try. */
4554
4555 if (rc == ERROR || (rc == OK && !some_deferred))
4556 {
4557 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4558 return TRUE; /* Each address has its status */
4559 }
4560
4561 /* If the result was DEFER or some individual addresses deferred, let
4562 the loop run to try other hosts with the deferred addresses, except for the
4563 case when we were trying to deliver down an existing channel and failed.
4564 Don't try any other hosts in this case. */
4565
4566 if (continue_hostname) break;
4567
4568 /* If the whole delivery, or some individual addresses, were deferred and
4569 there are more hosts that could be tried, do not count this host towards
4570 the hosts_max_try limit if the age of the message is greater than the
4571 maximum retry time for this host. This means we may try try all hosts,
4572 ignoring the limit, when messages have been around for some time. This is
4573 important because if we don't try all hosts, the address will never time
4574 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4575
4576 if ((rc == DEFER || some_deferred) && nexthost)
4577 {
4578 BOOL timedout;
4579 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4580
4581 if (retry && retry->rules)
4582 {
4583 retry_rule *last_rule;
4584 for (last_rule = retry->rules;
4585 last_rule->next;
4586 last_rule = last_rule->next);
4587 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
4588 }
4589 else timedout = TRUE; /* No rule => timed out */
4590
4591 if (timedout)
4592 {
4593 unexpired_hosts_tried--;
4594 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4595 "hosts_max_try (message older than host's retry time)\n");
4596 }
4597 }
4598 } /* End of loop for trying multiple hosts. */
4599
4600 /* If we failed to find a matching host in the list, for an already-open
4601 connection, just close it and start over with the list. This can happen
4602 for routing that changes from run to run, or big multi-IP sites with
4603 round-robin DNS. */
4604
4605 if (continue_hostname && !continue_host_tried)
4606 {
4607 int fd = cutthrough.fd >= 0 ? cutthrough.fd : 0;
4608
4609 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
4610 #ifdef SUPPORT_TLS
4611 if (tls_out.active == fd)
4612 {
4613 (void) tls_write(FALSE, US"QUIT\r\n", 6, FALSE);
4614 tls_close(FALSE, TLS_SHUTDOWN_NOWAIT);
4615 }
4616 else
4617 #else
4618 (void) write(fd, US"QUIT\r\n", 6);
4619 #endif
4620 (void) close(fd);
4621 cutthrough.fd = -1;
4622 continue_hostname = NULL;
4623 goto retry_non_continued;
4624 }
4625
4626 /* This is the end of the loop that repeats iff expired is TRUE and
4627 ob->delay_after_cutoff is FALSE. The second time round we will
4628 try those hosts that haven't been tried since the message arrived. */
4629
4630 DEBUG(D_transport)
4631 {
4632 debug_printf("all IP addresses skipped or deferred at least one address\n");
4633 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4634 debug_printf("retrying IP addresses not tried since message arrived\n");
4635 }
4636 }
4637
4638
4639 /* Get here if all IP addresses are skipped or defer at least one address. In
4640 MUA wrapper mode, this will happen only for connection or other non-message-
4641 specific failures. Force the delivery status for all addresses to FAIL. */
4642
4643 if (mua_wrapper)
4644 {
4645 for (addr = addrlist; addr; addr = addr->next)
4646 addr->transport_return = FAIL;
4647 goto END_TRANSPORT;
4648 }
4649
4650 /* In the normal, non-wrapper case, add a standard message to each deferred
4651 address if there hasn't been an error, that is, if it hasn't actually been
4652 tried this time. The variable "expired" will be FALSE if any deliveries were
4653 actually tried, or if there was at least one host that was not expired. That
4654 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4655 a delivery has been tried, an error code will be set, and the failing of the
4656 message is handled by the retry code later.
4657
4658 If queue_smtp is set, or this transport was called to send a subsequent message
4659 down an existing TCP/IP connection, and something caused the host not to be
4660 found, we end up here, but can detect these cases and handle them specially. */
4661
4662 for (addr = addrlist; addr; addr = addr->next)
4663 {
4664 /* If host is not NULL, it means that we stopped processing the host list
4665 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4666 means we need to behave as if some hosts were skipped because their retry
4667 time had not come. Specifically, this prevents the address from timing out.
4668 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4669 hosts were tried. */
4670
4671 if (host)
4672 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4673 {
4674 DEBUG(D_transport)
4675 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4676 "hosts were tried\n");
4677 }
4678 else
4679 {
4680 DEBUG(D_transport)
4681 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4682 setflag(addr, af_retry_skipped);
4683 }
4684
4685 if (queue_smtp) /* no deliveries attempted */
4686 {
4687 addr->transport_return = DEFER;
4688 addr->basic_errno = 0;
4689 addr->message = US"SMTP delivery explicitly queued";
4690 }
4691
4692 else if ( addr->transport_return == DEFER
4693 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4694 && !addr->message
4695 )
4696 {
4697 addr->basic_errno = ERRNO_HRETRY;
4698 if (continue_hostname)
4699 addr->message = US"no host found for existing SMTP connection";
4700 else if (expired)
4701 {
4702 setflag(addr, af_pass_message); /* This is not a security risk */
4703 addr->message = string_sprintf(
4704 "all hosts%s have been failing for a long time %s",
4705 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4706 ob->delay_after_cutoff
4707 ? US"(and retry time not reached)"
4708 : US"and were last tried after this message arrived");
4709
4710 /* If we are already using fallback hosts, or there are no fallback hosts
4711 defined, convert the result to FAIL to cause a bounce. */
4712
4713 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4714 addr->transport_return = FAIL;
4715 }
4716 else
4717 {
4718 const char * s;
4719 if (hosts_retry == hosts_total)
4720 s = "retry time not reached for any host%s";
4721 else if (hosts_fail == hosts_total)
4722 s = "all host address lookups%s failed permanently";
4723 else if (hosts_defer == hosts_total)
4724 s = "all host address lookups%s failed temporarily";
4725 else if (hosts_serial == hosts_total)
4726 s = "connection limit reached for all hosts%s";
4727 else if (hosts_fail+hosts_defer == hosts_total)
4728 s = "all host address lookups%s failed";
4729 else
4730 s = "some host address lookups failed and retry time "
4731 "not reached for other hosts or connection limit reached%s";
4732
4733 addr->message = string_sprintf(s,
4734 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4735 }
4736 }
4737 }
4738
4739 /* Update the database which keeps information about which messages are waiting
4740 for which hosts to become available. For some message-specific errors, the
4741 update_waiting flag is turned off because we don't want follow-on deliveries in
4742 those cases. If this transport instance is explicitly limited to one message
4743 per connection then follow-on deliveries are not possible and there's no need
4744 to create/update the per-transport wait-<transport_name> database. */
4745
4746 if (update_waiting && tblock->connection_max_messages != 1)
4747 transport_update_waiting(hostlist, tblock->name);
4748
4749 END_TRANSPORT:
4750
4751 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4752
4753 return TRUE; /* Each address has its status */
4754 }
4755
4756 #endif /*!MACRO_PREDEF*/
4757 /* vi: aw ai sw=2
4758 */
4759 /* End of transport/smtp.c */
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