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1d78f21950d62d0c681c119de329ab7ec030c87b
[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 { "authenticated_sender", opt_stringptr,
28 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
29 { "authenticated_sender_force", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
31 { "command_timeout", opt_time,
32 (void *)offsetof(smtp_transport_options_block, command_timeout) },
33 { "connect_timeout", opt_time,
34 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
35 { "connection_max_messages", opt_int | opt_public,
36 (void *)offsetof(transport_instance, connection_max_messages) },
37 { "data_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, data_timeout) },
39 { "delay_after_cutoff", opt_bool,
40 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 #ifndef DISABLE_DKIM
42 { "dkim_canon", opt_stringptr,
43 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
44 { "dkim_domain", opt_stringptr,
45 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
46 { "dkim_hash", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim.dkim_hash) },
48 { "dkim_identity", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_identity) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
58 #endif
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
75 { "helo_data", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, helo_data) },
77 { "hosts", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts) },
79 { "hosts_avoid_esmtp", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
81 { "hosts_avoid_pipelining", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
83 #ifdef SUPPORT_TLS
84 { "hosts_avoid_tls", opt_stringptr,
85 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
86 #endif
87 { "hosts_max_try", opt_int,
88 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
89 { "hosts_max_try_hardlimit", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
91 #ifdef SUPPORT_TLS
92 { "hosts_nopass_tls", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
94 { "hosts_noproxy_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_noproxy_tls) },
96 #endif
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
102 { "hosts_request_ocsp", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
104 #endif
105 { "hosts_require_auth", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
107 #ifdef SUPPORT_TLS
108 # ifdef EXPERIMENTAL_DANE
109 { "hosts_require_dane", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
111 # endif
112 # ifndef DISABLE_OCSP
113 { "hosts_require_ocsp", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
115 # endif
116 { "hosts_require_tls", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
118 #endif
119 { "hosts_try_auth", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
121 { "hosts_try_chunking", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
123 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
124 { "hosts_try_dane", opt_stringptr,
125 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
126 #endif
127 { "hosts_try_fastopen", opt_stringptr,
128 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
129 #ifndef DISABLE_PRDR
130 { "hosts_try_prdr", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
132 #endif
133 #ifdef SUPPORT_TLS
134 { "hosts_verify_avoid_tls", opt_stringptr,
135 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
136 #endif
137 { "interface", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, interface) },
139 { "keepalive", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, keepalive) },
141 { "lmtp_ignore_quota", opt_bool,
142 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
143 { "max_rcpt", opt_int | opt_public,
144 (void *)offsetof(transport_instance, max_addresses) },
145 { "multi_domain", opt_expand_bool | opt_public,
146 (void *)offsetof(transport_instance, multi_domain) },
147 { "port", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, port) },
149 { "protocol", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, protocol) },
151 { "retry_include_ip_address", opt_expand_bool,
152 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
153 { "serialize_hosts", opt_stringptr,
154 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
155 { "size_addition", opt_int,
156 (void *)offsetof(smtp_transport_options_block, size_addition) }
157 #ifdef SUPPORT_SOCKS
158 ,{ "socks_proxy", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
160 #endif
161 #ifdef SUPPORT_TLS
162 ,{ "tls_certificate", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
164 { "tls_crl", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_crl) },
166 { "tls_dh_min_bits", opt_int,
167 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
168 { "tls_privatekey", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
170 { "tls_require_ciphers", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
172 { "tls_sni", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_sni) },
174 { "tls_tempfail_tryclear", opt_bool,
175 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
176 { "tls_try_verify_hosts", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
178 { "tls_verify_cert_hostnames", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
180 { "tls_verify_certificates", opt_stringptr,
181 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
182 { "tls_verify_hosts", opt_stringptr,
183 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
184 #endif
185 };
186
187 /* Size of the options list. An extern variable has to be used so that its
188 address can appear in the tables drtables.c. */
189
190 int smtp_transport_options_count =
191 sizeof(smtp_transport_options)/sizeof(optionlist);
192
193
194 #ifdef MACRO_PREDEF
195
196 /* Dummy values */
197 smtp_transport_options_block smtp_transport_option_defaults = {0};
198 void smtp_transport_init(transport_instance *tblock) {}
199 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
200 void smtp_transport_closedown(transport_instance *tblock) {}
201
202 #else /*!MACRO_PREDEF*/
203
204
205 /* Default private options block for the smtp transport. */
206
207 smtp_transport_options_block smtp_transport_option_defaults = {
208 .hosts = NULL,
209 .fallback_hosts = NULL,
210 .hostlist = NULL,
211 .fallback_hostlist = NULL,
212 .authenticated_sender = NULL,
213 .helo_data = US"$primary_hostname",
214 .interface = NULL,
215 .port = NULL,
216 .protocol = US"smtp",
217 .dscp = NULL,
218 .serialize_hosts = NULL,
219 .hosts_try_auth = NULL,
220 .hosts_require_auth = NULL,
221 .hosts_try_chunking = US"*",
222 #ifdef EXPERIMENTAL_DANE
223 .hosts_try_dane = NULL,
224 .hosts_require_dane = NULL,
225 #endif
226 .hosts_try_fastopen = NULL,
227 #ifndef DISABLE_PRDR
228 .hosts_try_prdr = US"*",
229 #endif
230 #ifndef DISABLE_OCSP
231 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
232 .hosts_require_ocsp = NULL,
233 #endif
234 .hosts_require_tls = NULL,
235 .hosts_avoid_tls = NULL,
236 .hosts_verify_avoid_tls = NULL,
237 .hosts_avoid_pipelining = NULL,
238 .hosts_avoid_esmtp = NULL,
239 #ifdef SUPPORT_TLS
240 .hosts_nopass_tls = NULL,
241 .hosts_noproxy_tls = US"*",
242 #endif
243 .command_timeout = 5*60,
244 .connect_timeout = 5*60,
245 .data_timeout = 5*60,
246 .final_timeout = 10*60,
247 .size_addition = 1024,
248 .hosts_max_try = 5,
249 .hosts_max_try_hardlimit = 50,
250 .address_retry_include_sender = TRUE,
251 .allow_localhost = FALSE,
252 .authenticated_sender_force = FALSE,
253 .gethostbyname = FALSE,
254 .dns_qualify_single = TRUE,
255 .dns_search_parents = FALSE,
256 .dnssec = { .request=NULL, .require=NULL },
257 .delay_after_cutoff = TRUE,
258 .hosts_override = FALSE,
259 .hosts_randomize = FALSE,
260 .keepalive = TRUE,
261 .lmtp_ignore_quota = FALSE,
262 .expand_retry_include_ip_address = NULL,
263 .retry_include_ip_address = TRUE,
264 #ifdef SUPPORT_SOCKS
265 .socks_proxy = NULL,
266 #endif
267 #ifdef SUPPORT_TLS
268 .tls_certificate = NULL,
269 .tls_crl = NULL,
270 .tls_privatekey = NULL,
271 .tls_require_ciphers = NULL,
272 .tls_sni = NULL,
273 .tls_verify_certificates = US"system",
274 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
275 .tls_tempfail_tryclear = TRUE,
276 .tls_verify_hosts = NULL,
277 .tls_try_verify_hosts = US"*",
278 .tls_verify_cert_hostnames = US"*",
279 #endif
280 #ifndef DISABLE_DKIM
281 .dkim =
282 {.dkim_domain = NULL,
283 .dkim_identity = NULL,
284 .dkim_private_key = NULL,
285 .dkim_selector = NULL,
286 .dkim_canon = NULL,
287 .dkim_sign_headers = NULL,
288 .dkim_strict = NULL,
289 .dkim_hash = US"sha256",
290 .dot_stuffed = FALSE},
291 #endif
292 };
293
294 /* some DSN flags for use later */
295
296 static int rf_list[] = {rf_notify_never, rf_notify_success,
297 rf_notify_failure, rf_notify_delay };
298
299 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
300
301
302
303 /* Local statics */
304
305 static uschar *smtp_command; /* Points to last cmd for error messages */
306 static uschar *mail_command; /* Points to MAIL cmd for error messages */
307 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
308 static BOOL update_waiting; /* TRUE to update the "wait" database */
309
310 /*XXX move to smtp_context */
311 static BOOL pipelining_active; /* current transaction is in pipe mode */
312
313
314 /*************************************************
315 * Setup entry point *
316 *************************************************/
317
318 /* This function is called when the transport is about to be used,
319 but before running it in a sub-process. It is used for two things:
320
321 (1) To set the fallback host list in addresses, when delivering.
322 (2) To pass back the interface, port, protocol, and other options, for use
323 during callout verification.
324
325 Arguments:
326 tblock pointer to the transport instance block
327 addrlist list of addresses about to be transported
328 tf if not NULL, pointer to block in which to return options
329 uid the uid that will be set (not used)
330 gid the gid that will be set (not used)
331 errmsg place for error message (not used)
332
333 Returns: OK always (FAIL, DEFER not used)
334 */
335
336 static int
337 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
338 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
339 {
340 smtp_transport_options_block *ob =
341 (smtp_transport_options_block *)(tblock->options_block);
342
343 errmsg = errmsg; /* Keep picky compilers happy */
344 uid = uid;
345 gid = gid;
346
347 /* Pass back options if required. This interface is getting very messy. */
348
349 if (tf)
350 {
351 tf->interface = ob->interface;
352 tf->port = ob->port;
353 tf->protocol = ob->protocol;
354 tf->hosts = ob->hosts;
355 tf->hosts_override = ob->hosts_override;
356 tf->hosts_randomize = ob->hosts_randomize;
357 tf->gethostbyname = ob->gethostbyname;
358 tf->qualify_single = ob->dns_qualify_single;
359 tf->search_parents = ob->dns_search_parents;
360 tf->helo_data = ob->helo_data;
361 }
362
363 /* Set the fallback host list for all the addresses that don't have fallback
364 host lists, provided that the local host wasn't present in the original host
365 list. */
366
367 if (!testflag(addrlist, af_local_host_removed))
368 for (; addrlist; addrlist = addrlist->next)
369 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
370
371 return OK;
372 }
373
374
375
376 /*************************************************
377 * Initialization entry point *
378 *************************************************/
379
380 /* Called for each instance, after its options have been read, to
381 enable consistency checks to be done, or anything else that needs
382 to be set up.
383
384 Argument: pointer to the transport instance block
385 Returns: nothing
386 */
387
388 void
389 smtp_transport_init(transport_instance *tblock)
390 {
391 smtp_transport_options_block *ob =
392 (smtp_transport_options_block *)(tblock->options_block);
393
394 /* Retry_use_local_part defaults FALSE if unset */
395
396 if (tblock->retry_use_local_part == TRUE_UNSET)
397 tblock->retry_use_local_part = FALSE;
398
399 /* Set the default port according to the protocol */
400
401 if (ob->port == NULL)
402 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
403 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
404
405 /* Set up the setup entry point, to be called before subprocesses for this
406 transport. */
407
408 tblock->setup = smtp_transport_setup;
409
410 /* Complain if any of the timeouts are zero. */
411
412 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
413 ob->final_timeout <= 0)
414 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
415 "command, data, or final timeout value is zero for %s transport",
416 tblock->name);
417
418 /* If hosts_override is set and there are local hosts, set the global
419 flag that stops verify from showing router hosts. */
420
421 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
422
423 /* If there are any fallback hosts listed, build a chain of host items
424 for them, but do not do any lookups at this time. */
425
426 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
427 }
428
429
430
431
432
433 /*************************************************
434 * Set delivery info into all active addresses *
435 *************************************************/
436
437 /* Only addresses whose status is >= PENDING are relevant. A lesser
438 status means that an address is not currently being processed.
439
440 Arguments:
441 addrlist points to a chain of addresses
442 errno_value to put in each address's errno field
443 msg to put in each address's message field
444 rc to put in each address's transport_return field
445 pass_message if TRUE, set the "pass message" flag in the address
446 host if set, mark addrs as having used this host
447 smtp_greeting from peer
448 helo_response from peer
449
450 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
451 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
452 this particular type of timeout.
453
454 Returns: nothing
455 */
456
457 static void
458 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
459 BOOL pass_message, host_item * host
460 #ifdef EXPERIMENTAL_DSN_INFO
461 , const uschar * smtp_greeting, const uschar * helo_response
462 #endif
463 )
464 {
465 address_item *addr;
466 int orvalue = 0;
467 if (errno_value == ERRNO_CONNECTTIMEOUT)
468 {
469 errno_value = ETIMEDOUT;
470 orvalue = RTEF_CTOUT;
471 }
472 for (addr = addrlist; addr; addr = addr->next)
473 if (addr->transport_return >= PENDING)
474 {
475 addr->basic_errno = errno_value;
476 addr->more_errno |= orvalue;
477 if (msg)
478 {
479 addr->message = msg;
480 if (pass_message) setflag(addr, af_pass_message);
481 }
482 addr->transport_return = rc;
483 if (host)
484 {
485 addr->host_used = host;
486 #ifdef EXPERIMENTAL_DSN_INFO
487 if (smtp_greeting)
488 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
489 addr->smtp_greeting = smtp_greeting;
490
491 if (helo_response)
492 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
493 addr->helo_response = helo_response;
494 #endif
495 }
496 }
497 }
498
499 static void
500 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
501 BOOL pass_message)
502 {
503 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
504 #ifdef EXPERIMENTAL_DSN_INFO
505 , NULL, NULL
506 #endif
507 );
508 }
509
510
511 /*************************************************
512 * Check an SMTP response *
513 *************************************************/
514
515 /* This function is given an errno code and the SMTP response buffer
516 to analyse, together with the host identification for generating messages. It
517 sets an appropriate message and puts the first digit of the response code into
518 the yield variable. If no response was actually read, a suitable digit is
519 chosen.
520
521 Arguments:
522 host the current host, to get its name for messages
523 errno_value pointer to the errno value
524 more_errno from the top address for use with ERRNO_FILTER_FAIL
525 buffer the SMTP response buffer
526 yield where to put a one-digit SMTP response code
527 message where to put an error message
528 pass_message set TRUE if message is an SMTP response
529
530 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
531 */
532
533 static BOOL
534 check_response(host_item *host, int *errno_value, int more_errno,
535 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
536 {
537 uschar * pl = pipelining_active ? US"pipelined " : US"";
538 const uschar * s;
539
540 *yield = '4'; /* Default setting is to give a temporary error */
541
542 switch(*errno_value)
543 {
544 case ETIMEDOUT: /* Handle response timeout */
545 *message = US string_sprintf("SMTP timeout after %s%s",
546 pl, smtp_command);
547 if (transport_count > 0)
548 *message = US string_sprintf("%s (%d bytes written)", *message,
549 transport_count);
550 return FALSE;
551
552 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
553 s = string_printing(buffer);
554 while (isspace(*s)) s++;
555 *message = *s == 0
556 ? string_sprintf("Malformed SMTP reply (an empty line) "
557 "in response to %s%s", pl, smtp_command)
558 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
559 pl, smtp_command, s);
560 return FALSE;
561
562 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
563 can't send QUIT as we mustn't end the DATA. */
564 *message = string_sprintf("transport filter process failed (%d)%s",
565 more_errno,
566 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
567 return FALSE;
568
569 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
570 can't send QUIT as we mustn't end the DATA. */
571 *message =
572 string_sprintf("failed to expand headers_add or headers_remove: %s",
573 expand_string_message);
574 return FALSE;
575
576 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
577 *message = string_sprintf("failed to write a data block");
578 return FALSE;
579
580 #ifdef SUPPORT_I18N
581 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
582 *message = US"utf8 support required but not offered for forwarding";
583 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
584 return TRUE;
585 #endif
586 }
587
588 /* Handle error responses from the remote mailer. */
589
590 if (buffer[0] != 0)
591 {
592 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
593 "%s", pl, smtp_command, s = string_printing(buffer));
594 *pass_message = TRUE;
595 *yield = buffer[0];
596 return TRUE;
597 }
598
599 /* No data was read. If there is no errno, this must be the EOF (i.e.
600 connection closed) case, which causes deferral. An explicit connection reset
601 error has the same effect. Otherwise, put the host's identity in the message,
602 leaving the errno value to be interpreted as well. In all cases, we have to
603 assume the connection is now dead. */
604
605 if (*errno_value == 0 || *errno_value == ECONNRESET)
606 {
607 *errno_value = ERRNO_SMTPCLOSED;
608 *message = US string_sprintf("Remote host closed connection "
609 "in response to %s%s", pl, smtp_command);
610 }
611 else
612 *message = US string_sprintf("%s [%s]", host->name, host->address);
613
614 return FALSE;
615 }
616
617
618
619 /*************************************************
620 * Write error message to logs *
621 *************************************************/
622
623 /* This writes to the main log and to the message log.
624
625 Arguments:
626 host the current host
627 detail the current message (addr_item->message)
628 basic_errno the errno (addr_item->basic_errno)
629
630 Returns: nothing
631 */
632
633 static void
634 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
635 {
636
637
638 uschar *message = LOGGING(outgoing_port)
639 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
640 host->port == PORT_NONE ? 25 : host->port)
641 : string_sprintf("H=%s [%s]", host->name, host->address);
642
643 if (suffix)
644 {
645 message = string_sprintf("%s: %s", message, suffix);
646 if (basic_errno > 0)
647 message = string_sprintf("%s: %s", message, strerror(basic_errno));
648 }
649 else
650 message = string_sprintf("%s %s", message, exim_errstr(basic_errno));
651
652 log_write(0, LOG_MAIN, "%s", message);
653 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
654 }
655
656 static void
657 msglog_line(host_item * host, uschar * message)
658 {
659 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
660 host->name, host->address, message);
661 }
662
663
664
665 #ifndef DISABLE_EVENT
666 /*************************************************
667 * Post-defer action *
668 *************************************************/
669
670 /* This expands an arbitrary per-transport string.
671 It might, for example, be used to write to the database log.
672
673 Arguments:
674 addr the address item containing error information
675 host the current host
676
677 Returns: nothing
678 */
679
680 static void
681 deferred_event_raise(address_item *addr, host_item *host)
682 {
683 uschar * action = addr->transport->event_action;
684 const uschar * save_domain;
685 uschar * save_local;
686
687 if (!action)
688 return;
689
690 save_domain = deliver_domain;
691 save_local = deliver_localpart;
692
693 /*XXX would ip & port already be set up? */
694 deliver_host_address = string_copy(host->address);
695 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
696 event_defer_errno = addr->basic_errno;
697
698 router_name = addr->router->name;
699 transport_name = addr->transport->name;
700 deliver_domain = addr->domain;
701 deliver_localpart = addr->local_part;
702
703 (void) event_raise(action, US"msg:host:defer",
704 addr->message
705 ? addr->basic_errno > 0
706 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
707 : string_copy(addr->message)
708 : addr->basic_errno > 0
709 ? string_copy(US strerror(addr->basic_errno))
710 : NULL);
711
712 deliver_localpart = save_local;
713 deliver_domain = save_domain;
714 router_name = transport_name = NULL;
715 }
716 #endif
717
718 /*************************************************
719 * Synchronize SMTP responses *
720 *************************************************/
721
722 /* This function is called from smtp_deliver() to receive SMTP responses from
723 the server, and match them up with the commands to which they relate. When
724 PIPELINING is not in use, this function is called after every command, and is
725 therefore somewhat over-engineered, but it is simpler to use a single scheme
726 that works both with and without PIPELINING instead of having two separate sets
727 of code.
728
729 The set of commands that are buffered up with pipelining may start with MAIL
730 and may end with DATA; in between are RCPT commands that correspond to the
731 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
732 etc.) are never buffered.
733
734 Errors after MAIL or DATA abort the whole process leaving the response in the
735 buffer. After MAIL, pending responses are flushed, and the original command is
736 re-instated in big_buffer for error messages. For RCPT commands, the remote is
737 permitted to reject some recipient addresses while accepting others. However
738 certain errors clearly abort the whole process. Set the value in
739 transport_return to PENDING_OK if the address is accepted. If there is a
740 subsequent general error, it will get reset accordingly. If not, it will get
741 converted to OK at the end.
742
743 Arguments:
744 sx smtp connection context
745 count the number of responses to read
746 pending_DATA 0 if last command sent was not DATA
747 +1 if previously had a good recipient
748 -1 if not previously had a good recipient
749
750 Returns: 3 if at least one address had 2xx and one had 5xx
751 2 if at least one address had 5xx but none had 2xx
752 1 if at least one host had a 2xx response, but none had 5xx
753 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
754 -1 timeout while reading RCPT response
755 -2 I/O or other non-response error for RCPT
756 -3 DATA or MAIL failed - errno and buffer set
757 */
758
759 static int
760 sync_responses(smtp_context * sx, int count, int pending_DATA)
761 {
762 address_item *addr = sx->sync_addr;
763 smtp_transport_options_block *ob =
764 (smtp_transport_options_block *)sx->tblock->options_block;
765 int yield = 0;
766
767 /* Handle the response for a MAIL command. On error, reinstate the original
768 command in big_buffer for error message use, and flush any further pending
769 responses before returning, except after I/O errors and timeouts. */
770
771 if (sx->pending_MAIL)
772 {
773 count--;
774 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
775 '2', ob->command_timeout))
776 {
777 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
778 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
779 if (errno == 0 && sx->buffer[0] != 0)
780 {
781 uschar flushbuffer[4096];
782 int save_errno = 0;
783 if (sx->buffer[0] == '4')
784 {
785 save_errno = ERRNO_MAIL4XX;
786 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
787 }
788 while (count-- > 0)
789 {
790 if (!smtp_read_response(&sx->inblock, flushbuffer, sizeof(flushbuffer),
791 '2', ob->command_timeout)
792 && (errno != 0 || flushbuffer[0] == 0))
793 break;
794 }
795 errno = save_errno;
796 }
797
798 if (pending_DATA) count--; /* Number of RCPT responses to come */
799 while (count-- > 0) /* Mark any pending addrs with the host used */
800 {
801 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
802 addr->host_used = sx->host;
803 addr = addr->next;
804 }
805 return -3;
806 }
807 }
808
809 if (pending_DATA) count--; /* Number of RCPT responses to come */
810
811 /* Read and handle the required number of RCPT responses, matching each one up
812 with an address by scanning for the next address whose status is PENDING_DEFER.
813 */
814
815 while (count-- > 0)
816 {
817 while (addr->transport_return != PENDING_DEFER)
818 if (!(addr = addr->next))
819 return -2;
820
821 /* The address was accepted */
822 addr->host_used = sx->host;
823
824 if (smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
825 '2', ob->command_timeout))
826 {
827 yield |= 1;
828 addr->transport_return = PENDING_OK;
829
830 /* If af_dr_retry_exists is set, there was a routing delay on this address;
831 ensure that any address-specific retry record is expunged. We do this both
832 for the basic key and for the version that also includes the sender. */
833
834 if (testflag(addr, af_dr_retry_exists))
835 {
836 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
837 sender_address);
838 retry_add_item(addr, altkey, rf_delete);
839 retry_add_item(addr, addr->address_retry_key, rf_delete);
840 }
841 }
842
843 /* Timeout while reading the response */
844
845 else if (errno == ETIMEDOUT)
846 {
847 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
848 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
849 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
850 retry_add_item(addr, addr->address_retry_key, 0);
851 update_waiting = FALSE;
852 return -1;
853 }
854
855 /* Handle other errors in obtaining an SMTP response by returning -1. This
856 will cause all the addresses to be deferred. Restore the SMTP command in
857 big_buffer for which we are checking the response, so the error message
858 makes sense. */
859
860 else if (errno != 0 || sx->buffer[0] == 0)
861 {
862 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
863 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
864 return -2;
865 }
866
867 /* Handle SMTP permanent and temporary response codes. */
868
869 else
870 {
871 addr->message =
872 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
873 "%s", transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes),
874 string_printing(sx->buffer));
875 setflag(addr, af_pass_message);
876 if (!sx->verify)
877 msglog_line(sx->host, addr->message);
878
879 /* The response was 5xx */
880
881 if (sx->buffer[0] == '5')
882 {
883 addr->transport_return = FAIL;
884 yield |= 2;
885 }
886
887 /* The response was 4xx */
888
889 else
890 {
891 addr->transport_return = DEFER;
892 addr->basic_errno = ERRNO_RCPT4XX;
893 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
894
895 if (!sx->verify)
896 {
897 #ifndef DISABLE_EVENT
898 event_defer_errno = addr->more_errno;
899 msg_event_raise(US"msg:rcpt:host:defer", addr);
900 #endif
901
902 /* Log temporary errors if there are more hosts to be tried.
903 If not, log this last one in the == line. */
904
905 if (sx->host->next)
906 log_write(0, LOG_MAIN, "H=%s [%s]: %s",
907 sx->host->name, sx->host->address, addr->message);
908
909 #ifndef DISABLE_EVENT
910 else
911 msg_event_raise(US"msg:rcpt:defer", addr);
912 #endif
913
914 /* Do not put this message on the list of those waiting for specific
915 hosts, as otherwise it is likely to be tried too often. */
916
917 update_waiting = FALSE;
918
919 /* Add a retry item for the address so that it doesn't get tried again
920 too soon. If address_retry_include_sender is true, add the sender address
921 to the retry key. */
922
923 retry_add_item(addr,
924 ob->address_retry_include_sender
925 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
926 : addr->address_retry_key,
927 0);
928 }
929 }
930 }
931 } /* Loop for next RCPT response */
932
933 /* Update where to start at for the next block of responses, unless we
934 have already handled all the addresses. */
935
936 if (addr) sx->sync_addr = addr->next;
937
938 /* Handle a response to DATA. If we have not had any good recipients, either
939 previously or in this block, the response is ignored. */
940
941 if (pending_DATA != 0 &&
942 !smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
943 '3', ob->command_timeout))
944 {
945 int code;
946 uschar *msg;
947 BOOL pass_message;
948 if (pending_DATA > 0 || (yield & 1) != 0)
949 {
950 if (errno == 0 && sx->buffer[0] == '4')
951 {
952 errno = ERRNO_DATA4XX;
953 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
954 }
955 return -3;
956 }
957 (void)check_response(sx->host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
958 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
959 "is in use and there were no good recipients\n", msg);
960 }
961
962 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
963 present) received 3xx. If any RCPTs were handled and yielded anything other
964 than 4xx, yield will be set non-zero. */
965
966 return yield;
967 }
968
969
970
971 /* Do the client side of smtp-level authentication */
972 /*
973 Arguments:
974 buffer EHLO response from server (gets overwritten)
975 addrlist chain of potential addresses to deliver
976 host host to deliver to
977 ob transport options
978 ibp, obp comms channel control blocks
979
980 Returns:
981 OK Success, or failed (but not required): global "smtp_authenticated" set
982 DEFER Failed authentication (and was required)
983 ERROR Internal problem
984
985 FAIL_SEND Failed communications - transmit
986 FAIL - response
987 */
988
989 int
990 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
991 smtp_transport_options_block *ob, BOOL is_esmtp,
992 smtp_inblock *ibp, smtp_outblock *obp)
993 {
994 int require_auth;
995 uschar *fail_reason = US"server did not advertise AUTH support";
996
997 smtp_authenticated = FALSE;
998 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
999 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1000
1001 if (is_esmtp && !regex_AUTH) regex_AUTH =
1002 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1003 FALSE, TRUE);
1004
1005 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1006 {
1007 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1008 expand_nmax = -1; /* reset */
1009
1010 /* Must not do this check until after we have saved the result of the
1011 regex match above. */
1012
1013 if (require_auth == OK ||
1014 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1015 {
1016 auth_instance *au;
1017 fail_reason = US"no common mechanisms were found";
1018
1019 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1020
1021 /* Scan the configured authenticators looking for one which is configured
1022 for use as a client, which is not suppressed by client_condition, and
1023 whose name matches an authentication mechanism supported by the server.
1024 If one is found, attempt to authenticate by calling its client function.
1025 */
1026
1027 for (au = auths; !smtp_authenticated && au; au = au->next)
1028 {
1029 uschar *p = names;
1030 if (!au->client ||
1031 (au->client_condition != NULL &&
1032 !expand_check_condition(au->client_condition, au->name,
1033 US"client authenticator")))
1034 {
1035 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1036 au->name,
1037 (au->client)? "client_condition is false" :
1038 "not configured as a client");
1039 continue;
1040 }
1041
1042 /* Loop to scan supported server mechanisms */
1043
1044 while (*p)
1045 {
1046 int rc;
1047 int len = Ustrlen(au->public_name);
1048 while (isspace(*p)) p++;
1049
1050 if (strncmpic(au->public_name, p, len) != 0 ||
1051 (p[len] != 0 && !isspace(p[len])))
1052 {
1053 while (*p != 0 && !isspace(*p)) p++;
1054 continue;
1055 }
1056
1057 /* Found data for a listed mechanism. Call its client entry. Set
1058 a flag in the outblock so that data is overwritten after sending so
1059 that reflections don't show it. */
1060
1061 fail_reason = US"authentication attempt(s) failed";
1062 obp->authenticating = TRUE;
1063 rc = (au->info->clientcode)(au, ibp, obp,
1064 ob->command_timeout, buffer, bufsize);
1065 obp->authenticating = FALSE;
1066 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1067 au->name, rc);
1068
1069 /* A temporary authentication failure must hold up delivery to
1070 this host. After a permanent authentication failure, we carry on
1071 to try other authentication methods. If all fail hard, try to
1072 deliver the message unauthenticated unless require_auth was set. */
1073
1074 switch(rc)
1075 {
1076 case OK:
1077 smtp_authenticated = TRUE; /* stops the outer loop */
1078 client_authenticator = au->name;
1079 if (au->set_client_id != NULL)
1080 client_authenticated_id = expand_string(au->set_client_id);
1081 break;
1082
1083 /* Failure after writing a command */
1084
1085 case FAIL_SEND:
1086 return FAIL_SEND;
1087
1088 /* Failure after reading a response */
1089
1090 case FAIL:
1091 if (errno != 0 || buffer[0] != '5') return FAIL;
1092 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1093 au->name, host->name, host->address, buffer);
1094 break;
1095
1096 /* Failure by some other means. In effect, the authenticator
1097 decided it wasn't prepared to handle this case. Typically this
1098 is the result of "fail" in an expansion string. Do we need to
1099 log anything here? Feb 2006: a message is now put in the buffer
1100 if logging is required. */
1101
1102 case CANCELLED:
1103 if (*buffer != 0)
1104 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1105 "authentication H=%s [%s] %s", au->name, host->name,
1106 host->address, buffer);
1107 break;
1108
1109 /* Internal problem, message in buffer. */
1110
1111 case ERROR:
1112 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1113 DEFER, FALSE);
1114 return ERROR;
1115 }
1116
1117 break; /* If not authenticated, try next authenticator */
1118 } /* Loop for scanning supported server mechanisms */
1119 } /* Loop for further authenticators */
1120 }
1121 }
1122
1123 /* If we haven't authenticated, but are required to, give up. */
1124
1125 if (require_auth == OK && !smtp_authenticated)
1126 {
1127 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1128 string_sprintf("authentication required but %s", fail_reason), DEFER,
1129 FALSE);
1130 return DEFER;
1131 }
1132
1133 return OK;
1134 }
1135
1136
1137 /* Construct AUTH appendix string for MAIL TO */
1138 /*
1139 Arguments
1140 buffer to build string
1141 addrlist chain of potential addresses to deliver
1142 ob transport options
1143
1144 Globals smtp_authenticated
1145 client_authenticated_sender
1146 Return True on error, otherwise buffer has (possibly empty) terminated string
1147 */
1148
1149 BOOL
1150 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1151 smtp_transport_options_block *ob)
1152 {
1153 uschar *local_authenticated_sender = authenticated_sender;
1154
1155 #ifdef notdef
1156 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1157 #endif
1158
1159 if (ob->authenticated_sender != NULL)
1160 {
1161 uschar *new = expand_string(ob->authenticated_sender);
1162 if (new == NULL)
1163 {
1164 if (!expand_string_forcedfail)
1165 {
1166 uschar *message = string_sprintf("failed to expand "
1167 "authenticated_sender: %s", expand_string_message);
1168 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1169 return TRUE;
1170 }
1171 }
1172 else if (new[0] != 0) local_authenticated_sender = new;
1173 }
1174
1175 /* Add the authenticated sender address if present */
1176
1177 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1178 local_authenticated_sender != NULL)
1179 {
1180 string_format(buffer, bufsize, " AUTH=%s",
1181 auth_xtextencode(local_authenticated_sender,
1182 Ustrlen(local_authenticated_sender)));
1183 client_authenticated_sender = string_copy(local_authenticated_sender);
1184 }
1185 else
1186 *buffer= 0;
1187
1188 return FALSE;
1189 }
1190
1191
1192
1193 #ifdef EXPERIMENTAL_DANE
1194 /* Lookup TLSA record for host/port.
1195 Return: OK success with dnssec; DANE mode
1196 DEFER Do not use this host now, may retry later
1197 FAIL_FORCED No TLSA record; DANE not usable
1198 FAIL Do not use this connection
1199 */
1200
1201 int
1202 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1203 {
1204 /* move this out to host.c given the similarity to dns_lookup() ? */
1205 uschar buffer[300];
1206 const uschar * fullname = buffer;
1207 int rc;
1208 BOOL sec;
1209
1210 /* TLSA lookup string */
1211 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1212
1213 rc = dns_lookup(dnsa, buffer, T_TLSA, &fullname);
1214 sec = dns_is_secure(dnsa);
1215 DEBUG(D_transport)
1216 debug_printf("TLSA lookup ret %d %sDNSSEC\n", rc, sec ? "" : "not ");
1217
1218 switch (rc)
1219 {
1220 case DNS_AGAIN:
1221 return DEFER; /* just defer this TLS'd conn */
1222
1223 case DNS_SUCCEED:
1224 if (sec) return OK;
1225 log_write(0, LOG_MAIN,
1226 "DANE error: TLSA lookup for %s not DNSSEC", host->name);
1227 /*FALLTRHOUGH*/
1228
1229 case DNS_NODATA: /* no TLSA RR for this lookup */
1230 case DNS_NOMATCH: /* no records at all for this lookup */
1231 return dane_required ? FAIL : FAIL_FORCED;
1232
1233 default:
1234 case DNS_FAIL:
1235 return dane_required ? FAIL : DEFER;
1236 }
1237 }
1238 #endif
1239
1240
1241
1242 typedef struct smtp_compare_s
1243 {
1244 uschar *current_sender_address;
1245 struct transport_instance *tblock;
1246 } smtp_compare_t;
1247
1248
1249 /* Create a unique string that identifies this message, it is based on
1250 sender_address, helo_data and tls_certificate if enabled.
1251 */
1252
1253 static uschar *
1254 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1255 {
1256 address_item * addr1;
1257 uschar * if1 = US"";
1258 uschar * helo1 = US"";
1259 #ifdef SUPPORT_TLS
1260 uschar * tlsc1 = US"";
1261 #endif
1262 uschar * save_sender_address = sender_address;
1263 uschar * local_identity = NULL;
1264 smtp_transport_options_block * ob =
1265 (smtp_transport_options_block *)tblock->options_block;
1266
1267 sender_address = sender;
1268
1269 addr1 = deliver_make_addr (sender, TRUE);
1270 deliver_set_expansions(addr1);
1271
1272 if (ob->interface)
1273 if1 = expand_string(ob->interface);
1274
1275 if (ob->helo_data)
1276 helo1 = expand_string(ob->helo_data);
1277
1278 #ifdef SUPPORT_TLS
1279 if (ob->tls_certificate)
1280 tlsc1 = expand_string(ob->tls_certificate);
1281 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1282 #else
1283 local_identity = string_sprintf ("%s^%s", if1, helo1);
1284 #endif
1285
1286 deliver_set_expansions(NULL);
1287 sender_address = save_sender_address;
1288
1289 return local_identity;
1290 }
1291
1292
1293
1294 /* This routine is a callback that is called from transport_check_waiting.
1295 This function will evaluate the incoming message versus the previous
1296 message. If the incoming message is using a different local identity then
1297 we will veto this new message. */
1298
1299 static BOOL
1300 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1301 {
1302 uschar * message_local_identity,
1303 * current_local_identity,
1304 * new_sender_address;
1305
1306 current_local_identity =
1307 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1308
1309 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1310 return 0;
1311
1312 message_local_identity =
1313 smtp_local_identity(new_sender_address, s_compare->tblock);
1314
1315 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1316 }
1317
1318
1319
1320 static uschar
1321 ehlo_response(uschar * buf, uschar checks)
1322 {
1323 size_t bsize = Ustrlen(buf);
1324
1325 #ifdef SUPPORT_TLS
1326 if ( checks & OPTION_TLS
1327 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1328 checks &= ~OPTION_TLS;
1329 #endif
1330
1331 if ( checks & OPTION_IGNQ
1332 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1333 PCRE_EOPT, NULL, 0) < 0)
1334 checks &= ~OPTION_IGNQ;
1335
1336 if ( checks & OPTION_CHUNKING
1337 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1338 checks &= ~OPTION_CHUNKING;
1339
1340 #ifndef DISABLE_PRDR
1341 if ( checks & OPTION_PRDR
1342 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1343 checks &= ~OPTION_PRDR;
1344 #endif
1345
1346 #ifdef SUPPORT_I18N
1347 if ( checks & OPTION_UTF8
1348 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1349 checks &= ~OPTION_UTF8;
1350 #endif
1351
1352 if ( checks & OPTION_DSN
1353 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1354 checks &= ~OPTION_DSN;
1355
1356 if ( checks & OPTION_PIPE
1357 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1358 PCRE_EOPT, NULL, 0) < 0)
1359 checks &= ~OPTION_PIPE;
1360
1361 if ( checks & OPTION_SIZE
1362 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1363 checks &= ~OPTION_SIZE;
1364
1365 return checks;
1366 }
1367
1368
1369
1370 /* Callback for emitting a BDAT data chunk header.
1371
1372 If given a nonzero size, first flush any buffered SMTP commands
1373 then emit the command.
1374
1375 Reap previous SMTP command responses if requested, and always reap
1376 the response from a previous BDAT command.
1377
1378 Args:
1379 tctx transport context
1380 chunk_size value for SMTP BDAT command
1381 flags
1382 tc_chunk_last add LAST option to SMTP BDAT command
1383 tc_reap_prev reap response to previous SMTP commands
1384
1385 Returns: OK or ERROR
1386 */
1387
1388 static int
1389 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1390 unsigned flags)
1391 {
1392 smtp_transport_options_block * ob =
1393 (smtp_transport_options_block *)(tctx->tblock->options_block);
1394 smtp_context * sx = tctx->smtp_context;
1395 int cmd_count = 0;
1396 int prev_cmd_count;
1397
1398 /* Write SMTP chunk header command. If not reaping responses, note that
1399 there may be more writes (like, the chunk data) done soon. */
1400
1401 if (chunk_size > 0)
1402 {
1403 if((cmd_count = smtp_write_command(&sx->outblock,
1404 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1405 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1406 ) < 0) return ERROR;
1407 if (flags & tc_chunk_last)
1408 data_command = string_copy(big_buffer); /* Save for later error message */
1409 }
1410
1411 prev_cmd_count = cmd_count += sx->cmd_count;
1412
1413 /* Reap responses for any previous, but not one we just emitted */
1414
1415 if (chunk_size > 0)
1416 prev_cmd_count--;
1417 if (sx->pending_BDAT)
1418 prev_cmd_count--;
1419
1420 if (flags & tc_reap_prev && prev_cmd_count > 0)
1421 {
1422 DEBUG(D_transport) debug_printf("look for %d responses"
1423 " for previous pipelined cmds\n", prev_cmd_count);
1424
1425 switch(sync_responses(sx, prev_cmd_count, 0))
1426 {
1427 case 1: /* 2xx (only) => OK */
1428 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1429 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1430 case 0: break; /* No 2xx or 5xx, but no probs */
1431
1432 case -1: /* Timeout on RCPT */
1433 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1434 }
1435 cmd_count = 1;
1436 if (!sx->pending_BDAT)
1437 pipelining_active = FALSE;
1438 }
1439
1440 /* Reap response for an outstanding BDAT */
1441
1442 if (sx->pending_BDAT)
1443 {
1444 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1445
1446 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1447 ob->command_timeout))
1448 {
1449 if (errno == 0 && sx->buffer[0] == '4')
1450 {
1451 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1452 sx->addrlist->more_errno |=
1453 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1454 }
1455 return ERROR;
1456 }
1457 cmd_count--;
1458 sx->pending_BDAT = FALSE;
1459 pipelining_active = FALSE;
1460 }
1461 else if (chunk_size > 0)
1462 sx->pending_BDAT = TRUE;
1463
1464
1465 sx->cmd_count = cmd_count;
1466 return OK;
1467 }
1468
1469
1470
1471 /*************************************************
1472 * Make connection for given message *
1473 *************************************************/
1474
1475 /*
1476 Arguments:
1477 ctx connection context
1478 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1479 a second attempt after TLS initialization fails
1480
1481 Returns: OK - the connection was made and the delivery attempted;
1482 fd is set in the conn context, tls_out set up.
1483 DEFER - the connection could not be made, or something failed
1484 while setting up the SMTP session, or there was a
1485 non-message-specific error, such as a timeout.
1486 ERROR - helo_data or add_headers or authenticated_sender is
1487 specified for this transport, and the string failed
1488 to expand
1489 */
1490 int
1491 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1492 {
1493 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1494 dns_answer tlsa_dnsa;
1495 #endif
1496 BOOL pass_message = FALSE;
1497 uschar * message = NULL;
1498 int yield = OK;
1499 int rc;
1500
1501 sx->ob = (smtp_transport_options_block *) sx->tblock->options_block;
1502
1503 sx->lmtp = strcmpic(sx->ob->protocol, US"lmtp") == 0;
1504 sx->smtps = strcmpic(sx->ob->protocol, US"smtps") == 0;
1505 sx->ok = FALSE;
1506 sx->send_rset = TRUE;
1507 sx->send_quit = TRUE;
1508 sx->setting_up = TRUE;
1509 sx->esmtp = TRUE;
1510 sx->esmtp_sent = FALSE;
1511 #ifdef SUPPORT_I18N
1512 sx->utf8_needed = FALSE;
1513 #endif
1514 sx->dsn_all_lasthop = TRUE;
1515 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1516 sx->dane = FALSE;
1517 sx->dane_required = verify_check_given_host(&sx->ob->hosts_require_dane, sx->host) == OK;
1518 #endif
1519
1520 if ((sx->max_rcpt = sx->tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1521 sx->peer_offered = 0;
1522 sx->avoid_option = 0;
1523 sx->igquotstr = US"";
1524 if (!sx->helo_data) sx->helo_data = sx->ob->helo_data;
1525 #ifdef EXPERIMENTAL_DSN_INFO
1526 sx->smtp_greeting = NULL;
1527 sx->helo_response = NULL;
1528 #endif
1529
1530 smtp_command = US"initial connection";
1531 sx->buffer[0] = '\0';
1532
1533 /* Set up the buffer for reading SMTP response packets. */
1534
1535 sx->inblock.buffer = sx->inbuffer;
1536 sx->inblock.buffersize = sizeof(sx->inbuffer);
1537 sx->inblock.ptr = sx->inbuffer;
1538 sx->inblock.ptrend = sx->inbuffer;
1539
1540 /* Set up the buffer for holding SMTP commands while pipelining */
1541
1542 sx->outblock.buffer = sx->outbuffer;
1543 sx->outblock.buffersize = sizeof(sx->outbuffer);
1544 sx->outblock.ptr = sx->outbuffer;
1545 sx->outblock.cmd_count = 0;
1546 sx->outblock.authenticating = FALSE;
1547
1548 /* Reset the parameters of a TLS session. */
1549
1550 tls_out.bits = 0;
1551 tls_out.cipher = NULL; /* the one we may use for this transport */
1552 tls_out.ourcert = NULL;
1553 tls_out.peercert = NULL;
1554 tls_out.peerdn = NULL;
1555 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1556 tls_out.sni = NULL;
1557 #endif
1558 tls_out.ocsp = OCSP_NOT_REQ;
1559
1560 /* Flip the legacy TLS-related variables over to the outbound set in case
1561 they're used in the context of the transport. Don't bother resetting
1562 afterward (when being used by a transport) as we're in a subprocess.
1563 For verify, unflipped once the callout is dealt with */
1564
1565 tls_modify_variables(&tls_out);
1566
1567 #ifndef SUPPORT_TLS
1568 if (sx->smtps)
1569 {
1570 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1571 DEFER, FALSE);
1572 return ERROR;
1573 }
1574 #endif
1575
1576 /* Make a connection to the host if this isn't a continued delivery, and handle
1577 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1578 specially so they can be identified for retries. */
1579
1580 if (!continue_hostname)
1581 {
1582 if (sx->verify)
1583 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->interface, sx->port);
1584
1585 /* Get the actual port the connection will use, into sx->host */
1586
1587 smtp_port_for_connect(sx->host, sx->port);
1588
1589 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1590 /* Do TLSA lookup for DANE */
1591 {
1592 tls_out.dane_verified = FALSE;
1593 tls_out.tlsa_usage = 0;
1594
1595 if (sx->host->dnssec == DS_YES)
1596 {
1597 if( sx->dane_required
1598 || verify_check_given_host(&sx->ob->hosts_try_dane, sx->host) == OK
1599 )
1600 switch (rc = tlsa_lookup(sx->host, &tlsa_dnsa, sx->dane_required))
1601 {
1602 case OK: sx->dane = TRUE;
1603 sx->ob->tls_tempfail_tryclear = FALSE;
1604 break;
1605 case FAIL_FORCED: break;
1606 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1607 string_sprintf("DANE error: tlsa lookup %s",
1608 rc == DEFER ? "DEFER" : "FAIL"),
1609 rc, FALSE);
1610 return rc;
1611 }
1612 }
1613 else if (sx->dane_required)
1614 {
1615 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1616 string_sprintf("DANE error: %s lookup not DNSSEC", sx->host->name),
1617 FAIL, FALSE);
1618 return FAIL;
1619 }
1620 }
1621 #endif /*DANE*/
1622
1623 /* Make the TCP connection */
1624
1625 sx->inblock.sock = sx->outblock.sock =
1626 smtp_connect(sx->host, sx->host_af, sx->interface,
1627 sx->ob->connect_timeout, sx->tblock);
1628
1629 if (sx->inblock.sock < 0)
1630 {
1631 uschar * msg = NULL;
1632 if (sx->verify)
1633 {
1634 msg = US strerror(errno);
1635 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
1636 }
1637 set_errno_nohost(sx->addrlist,
1638 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1639 sx->verify ? string_sprintf("could not connect: %s", msg)
1640 : NULL,
1641 DEFER, FALSE);
1642 sx->send_quit = FALSE;
1643 return DEFER;
1644 }
1645
1646 /* Expand the greeting message while waiting for the initial response. (Makes
1647 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1648 delayed till here so that $sending_interface and $sending_port are set. */
1649
1650 if (sx->helo_data)
1651 if (!(sx->helo_data = expand_string(sx->helo_data)))
1652 if (sx->verify)
1653 log_write(0, LOG_MAIN|LOG_PANIC,
1654 "<%s>: failed to expand transport's helo_data value for callout: %s",
1655 sx->addrlist->address, expand_string_message);
1656
1657 #ifdef SUPPORT_I18N
1658 if (sx->helo_data)
1659 {
1660 expand_string_message = NULL;
1661 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
1662 &expand_string_message)),
1663 expand_string_message)
1664 if (sx->verify)
1665 log_write(0, LOG_MAIN|LOG_PANIC,
1666 "<%s>: failed to expand transport's helo_data value for callout: %s",
1667 sx->addrlist->address, expand_string_message);
1668 else
1669 sx->helo_data = NULL;
1670 }
1671 #endif
1672
1673 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1674 is nevertheless a reasonably clean way of programming this kind of logic,
1675 where you want to escape on any error. */
1676
1677 if (!sx->smtps)
1678 {
1679 BOOL good_response;
1680
1681 #ifdef TCP_QUICKACK
1682 (void) setsockopt(sx->inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1683 #endif
1684 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1685 '2', sx->ob->command_timeout);
1686 #ifdef EXPERIMENTAL_DSN_INFO
1687 sx->smtp_greeting = string_copy(sx->buffer);
1688 #endif
1689 if (!good_response) goto RESPONSE_FAILED;
1690
1691 #ifndef DISABLE_EVENT
1692 {
1693 uschar * s;
1694 lookup_dnssec_authenticated = sx->host->dnssec==DS_YES ? US"yes"
1695 : sx->host->dnssec==DS_NO ? US"no" : NULL;
1696 s = event_raise(sx->tblock->event_action, US"smtp:connect", sx->buffer);
1697 if (s)
1698 {
1699 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
1700 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1701 DEFER, FALSE);
1702 yield = DEFER;
1703 goto SEND_QUIT;
1704 }
1705 }
1706 #endif
1707
1708 /* Now check if the helo_data expansion went well, and sign off cleanly if
1709 it didn't. */
1710
1711 if (!sx->helo_data)
1712 {
1713 message = string_sprintf("failed to expand helo_data: %s",
1714 expand_string_message);
1715 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1716 yield = DEFER;
1717 goto SEND_QUIT;
1718 }
1719 }
1720
1721 /** Debugging without sending a message
1722 sx->addrlist->transport_return = DEFER;
1723 goto SEND_QUIT;
1724 **/
1725
1726 /* Errors that occur after this point follow an SMTP command, which is
1727 left in big_buffer by smtp_write_command() for use in error messages. */
1728
1729 smtp_command = big_buffer;
1730
1731 /* Tell the remote who we are...
1732
1733 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1734 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1735 greeting is of this form. The assumption was that the far end supports it
1736 properly... but experience shows that there are some that give 5xx responses,
1737 even though the banner includes "ESMTP" (there's a bloody-minded one that
1738 says "ESMTP not spoken here"). Cope with that case.
1739
1740 September 2000: Time has passed, and it seems reasonable now to always send
1741 EHLO at the start. It is also convenient to make the change while installing
1742 the TLS stuff.
1743
1744 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1745 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1746 would be no way to send out the mails, so there is now a host list
1747 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1748 PIPELINING problem as well. Maybe it can also be useful to cure other
1749 problems with broken servers.
1750
1751 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1752 Then somebody tried it with a Microsoft mailer... It seems that all other
1753 mailers use upper case for some reason (the RFC is quite clear about case
1754 independence) so, for peace of mind, I gave in. */
1755
1756 sx->esmtp = verify_check_given_host(&sx->ob->hosts_avoid_esmtp, sx->host) != OK;
1757
1758 /* Alas; be careful, since this goto is not an error-out, so conceivably
1759 we might set data between here and the target which we assume to exist
1760 and be usable. I can see this coming back to bite us. */
1761 #ifdef SUPPORT_TLS
1762 if (sx->smtps)
1763 {
1764 smtp_peer_options |= OPTION_TLS;
1765 suppress_tls = FALSE;
1766 sx->ob->tls_tempfail_tryclear = FALSE;
1767 smtp_command = US"SSL-on-connect";
1768 goto TLS_NEGOTIATE;
1769 }
1770 #endif
1771
1772 if (sx->esmtp)
1773 {
1774 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "%s %s\r\n",
1775 sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
1776 goto SEND_FAILED;
1777 sx->esmtp_sent = TRUE;
1778 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1779 sx->ob->command_timeout))
1780 {
1781 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
1782 {
1783 #ifdef EXPERIMENTAL_DSN_INFO
1784 sx->helo_response = string_copy(sx->buffer);
1785 #endif
1786 goto RESPONSE_FAILED;
1787 }
1788 sx->esmtp = FALSE;
1789 }
1790 #ifdef EXPERIMENTAL_DSN_INFO
1791 sx->helo_response = string_copy(sx->buffer);
1792 #endif
1793 }
1794 else
1795 DEBUG(D_transport)
1796 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1797
1798 if (!sx->esmtp)
1799 {
1800 BOOL good_response;
1801 int n = sizeof(sx->buffer);
1802 uschar * rsp = sx->buffer;
1803
1804 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
1805 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
1806
1807 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
1808 goto SEND_FAILED;
1809 good_response = smtp_read_response(&sx->inblock, rsp, n,
1810 '2', sx->ob->command_timeout);
1811 #ifdef EXPERIMENTAL_DSN_INFO
1812 sx->helo_response = string_copy(rsp);
1813 #endif
1814 if (!good_response)
1815 {
1816 /* Handle special logging for a closed connection after HELO
1817 when had previously sent EHLO */
1818
1819 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1820 {
1821 errno = ERRNO_SMTPCLOSED;
1822 goto EHLOHELO_FAILED;
1823 }
1824 memmove(sx->buffer, rsp, Ustrlen(rsp));
1825 goto RESPONSE_FAILED;
1826 }
1827 }
1828
1829 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
1830
1831 if (sx->esmtp || sx->lmtp)
1832 {
1833 sx->peer_offered = ehlo_response(sx->buffer,
1834 OPTION_TLS /* others checked later */
1835 );
1836
1837 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1838
1839 #ifdef SUPPORT_TLS
1840 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
1841 #endif
1842 }
1843 }
1844
1845 /* For continuing deliveries down the same channel, having re-exec'd the socket
1846 is the standard input; for a socket held open from verify it is recorded
1847 in the cutthrough context block. Either way we don't need to redo EHLO here
1848 (but may need to do so for TLS - see below).
1849 Set up the pointer to where subsequent commands will be left, for
1850 error messages. Note that smtp_peer_options will have been
1851 set from the command line if they were set in the process that passed the
1852 connection on. */
1853
1854 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1855 as the continue goes via transport_pass_socket() and doublefork and exec.
1856 It does not wait. Unclear how we keep separate host's responses
1857 separate - we could match up by host ip+port as a bodge. */
1858
1859 else
1860 {
1861 if (cutthrough.fd >= 0 && cutthrough.callout_hold_only)
1862 {
1863 sx->inblock.sock = sx->outblock.sock = cutthrough.fd;
1864 sx->host->port = sx->port = cutthrough.host.port;
1865 }
1866 else
1867 {
1868 sx->inblock.sock = sx->outblock.sock = 0; /* stdin */
1869 smtp_port_for_connect(sx->host, sx->port); /* Record the port that was used */
1870 }
1871 smtp_command = big_buffer;
1872 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
1873
1874 /* For a continued connection with TLS being proxied for us, or a
1875 held-open verify connection with TLS, nothing more to do. */
1876
1877 if ( continue_proxy_cipher
1878 || (cutthrough.fd >= 0 && cutthrough.callout_hold_only && cutthrough.is_tls)
1879 )
1880 {
1881 sx->peer_offered = smtp_peer_options;
1882 pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
1883 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
1884 continue_proxy_cipher ? "proxied" : "verify conn with");
1885 return OK;
1886 }
1887 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
1888 }
1889
1890 /* If TLS is available on this connection, whether continued or not, attempt to
1891 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1892 send another EHLO - the server may give a different answer in secure mode. We
1893 use a separate buffer for reading the response to STARTTLS so that if it is
1894 negative, the original EHLO data is available for subsequent analysis, should
1895 the client not be required to use TLS. If the response is bad, copy the buffer
1896 for error analysis. */
1897
1898 #ifdef SUPPORT_TLS
1899 if ( smtp_peer_options & OPTION_TLS
1900 && !suppress_tls
1901 && verify_check_given_host(&sx->ob->hosts_avoid_tls, sx->host) != OK
1902 && ( !sx->verify
1903 || verify_check_given_host(&sx->ob->hosts_verify_avoid_tls, sx->host) != OK
1904 ) )
1905 {
1906 uschar buffer2[4096];
1907 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "STARTTLS\r\n") < 0)
1908 goto SEND_FAILED;
1909
1910 /* If there is an I/O error, transmission of this message is deferred. If
1911 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1912 false, we also defer. However, if there is a temporary rejection of STARTTLS
1913 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1914 STARTTLS, we carry on. This means we will try to send the message in clear,
1915 unless the host is in hosts_require_tls (tested below). */
1916
1917 if (!smtp_read_response(&sx->inblock, buffer2, sizeof(buffer2), '2',
1918 sx->ob->command_timeout))
1919 {
1920 if ( errno != 0
1921 || buffer2[0] == 0
1922 || (buffer2[0] == '4' && !sx->ob->tls_tempfail_tryclear)
1923 )
1924 {
1925 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
1926 sx->buffer[sizeof(sx->buffer)-1] = '\0';
1927 goto RESPONSE_FAILED;
1928 }
1929 }
1930
1931 /* STARTTLS accepted: try to negotiate a TLS session. */
1932
1933 else
1934 TLS_NEGOTIATE:
1935 {
1936 address_item * addr;
1937 uschar * errstr;
1938 int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock,
1939 # ifdef EXPERIMENTAL_DANE
1940 sx->dane ? &tlsa_dnsa : NULL,
1941 # endif
1942 &errstr);
1943
1944 /* TLS negotiation failed; give an error. From outside, this function may
1945 be called again to try in clear on a new connection, if the options permit
1946 it for this host. */
1947
1948 if (rc != OK)
1949 {
1950 # ifdef EXPERIMENTAL_DANE
1951 if (sx->dane) log_write(0, LOG_MAIN,
1952 "DANE attempt failed; TLS connection to %s [%s]: %s",
1953 sx->host->name, sx->host->address, errstr);
1954 # endif
1955
1956 errno = ERRNO_TLSFAILURE;
1957 message = string_sprintf("TLS session: %s", errstr);
1958 sx->send_quit = FALSE;
1959 goto TLS_FAILED;
1960 }
1961
1962 /* TLS session is set up */
1963
1964 smtp_peer_options_wrap = smtp_peer_options;
1965 for (addr = sx->addrlist; addr; addr = addr->next)
1966 if (addr->transport_return == PENDING_DEFER)
1967 {
1968 addr->cipher = tls_out.cipher;
1969 addr->ourcert = tls_out.ourcert;
1970 addr->peercert = tls_out.peercert;
1971 addr->peerdn = tls_out.peerdn;
1972 addr->ocsp = tls_out.ocsp;
1973 }
1974 }
1975 }
1976
1977 /* if smtps, we'll have smtp_command set to something else; always safe to
1978 reset it here. */
1979 smtp_command = big_buffer;
1980
1981 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1982 helo_data is null, we are dealing with a connection that was passed from
1983 another process, and so we won't have expanded helo_data above. We have to
1984 expand it here. $sending_ip_address and $sending_port are set up right at the
1985 start of the Exim process (in exim.c). */
1986
1987 if (tls_out.active >= 0)
1988 {
1989 char *greeting_cmd;
1990 BOOL good_response;
1991
1992 if (!sx->helo_data && !(sx->helo_data = expand_string(sx->ob->helo_data)))
1993 {
1994 uschar *message = string_sprintf("failed to expand helo_data: %s",
1995 expand_string_message);
1996 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1997 yield = DEFER;
1998 goto SEND_QUIT;
1999 }
2000
2001 /* For SMTPS we need to wait for the initial OK response. */
2002 if (sx->smtps)
2003 {
2004 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
2005 '2', sx->ob->command_timeout);
2006 #ifdef EXPERIMENTAL_DSN_INFO
2007 sx->smtp_greeting = string_copy(sx->buffer);
2008 #endif
2009 if (!good_response) goto RESPONSE_FAILED;
2010 }
2011
2012 if (sx->esmtp)
2013 greeting_cmd = "EHLO";
2014 else
2015 {
2016 greeting_cmd = "HELO";
2017 DEBUG(D_transport)
2018 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2019 }
2020
2021 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "%s %s\r\n",
2022 sx->lmtp ? "LHLO" : greeting_cmd, sx->helo_data) < 0)
2023 goto SEND_FAILED;
2024 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
2025 '2', sx->ob->command_timeout);
2026 #ifdef EXPERIMENTAL_DSN_INFO
2027 sx->helo_response = string_copy(sx->buffer);
2028 #endif
2029 if (!good_response) goto RESPONSE_FAILED;
2030 smtp_peer_options = 0;
2031 }
2032
2033 /* If the host is required to use a secure channel, ensure that we
2034 have one. */
2035
2036 else if ( sx->smtps
2037 # ifdef EXPERIMENTAL_DANE
2038 || sx->dane
2039 # endif
2040 || verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
2041 )
2042 {
2043 errno = ERRNO_TLSREQUIRED;
2044 message = string_sprintf("a TLS session is required, but %s",
2045 smtp_peer_options & OPTION_TLS
2046 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2047 goto TLS_FAILED;
2048 }
2049 #endif /*SUPPORT_TLS*/
2050
2051 /* If TLS is active, we have just started it up and re-done the EHLO command,
2052 so its response needs to be analyzed. If TLS is not active and this is a
2053 continued session down a previously-used socket, we haven't just done EHLO, so
2054 we skip this. */
2055
2056 if (continue_hostname == NULL
2057 #ifdef SUPPORT_TLS
2058 || tls_out.active >= 0
2059 #endif
2060 )
2061 {
2062 if (sx->esmtp || sx->lmtp)
2063 {
2064 sx->peer_offered = ehlo_response(sx->buffer,
2065 0 /* no TLS */
2066 | (sx->lmtp && sx->ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2067 | OPTION_CHUNKING
2068 | OPTION_PRDR
2069 #ifdef SUPPORT_I18N
2070 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2071 /*XXX if we hand peercaps on to continued-conn processes,
2072 must not depend on this addr */
2073 #endif
2074 | OPTION_DSN
2075 | OPTION_PIPE
2076 | (sx->ob->size_addition >= 0 ? OPTION_SIZE : 0)
2077 );
2078
2079 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2080 lmtp_ignore_quota option was set. */
2081
2082 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2083
2084 /* If the response to EHLO specified support for the SIZE parameter, note
2085 this, provided size_addition is non-negative. */
2086
2087 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2088
2089 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2090 the current host, esmtp will be false, so PIPELINING can never be used. If
2091 the current host matches hosts_avoid_pipelining, don't do it. */
2092
2093 if ( sx->peer_offered & OPTION_PIPE
2094 && verify_check_given_host(&sx->ob->hosts_avoid_pipelining, sx->host) != OK)
2095 smtp_peer_options |= OPTION_PIPE;
2096
2097 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2098 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2099
2100 if ( sx->peer_offered & OPTION_CHUNKING
2101 && verify_check_given_host(&sx->ob->hosts_try_chunking, sx->host) != OK)
2102 sx->peer_offered &= ~OPTION_CHUNKING;
2103
2104 if (sx->peer_offered & OPTION_CHUNKING)
2105 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2106
2107 #ifndef DISABLE_PRDR
2108 if ( sx->peer_offered & OPTION_PRDR
2109 && verify_check_given_host(&sx->ob->hosts_try_prdr, sx->host) != OK)
2110 sx->peer_offered &= ~OPTION_PRDR;
2111
2112 if (sx->peer_offered & OPTION_PRDR)
2113 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2114 #endif
2115
2116 /* Note if the server supports DSN */
2117 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2118 DEBUG(D_transport) debug_printf("%susing DSN\n",
2119 sx->peer_offered & OPTION_DSN ? "" : "not ");
2120
2121 /* Note if the response to EHLO specifies support for the AUTH extension.
2122 If it has, check that this host is one we want to authenticate to, and do
2123 the business. The host name and address must be available when the
2124 authenticator's client driver is running. */
2125
2126 switch (yield = smtp_auth(sx->buffer, sizeof(sx->buffer), sx->addrlist, sx->host,
2127 sx->ob, sx->esmtp, &sx->inblock, &sx->outblock))
2128 {
2129 default: goto SEND_QUIT;
2130 case OK: break;
2131 case FAIL_SEND: goto SEND_FAILED;
2132 case FAIL: goto RESPONSE_FAILED;
2133 }
2134 }
2135 }
2136 pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2137
2138 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2139 message-specific. */
2140
2141 sx->setting_up = FALSE;
2142
2143 #ifdef SUPPORT_I18N
2144 if (sx->addrlist->prop.utf8_msg)
2145 {
2146 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2147 && !sx->addrlist->prop.utf8_downcvt_maybe;
2148 DEBUG(D_transport) if (!sx->utf8_needed)
2149 debug_printf("utf8: %s downconvert\n",
2150 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2151 }
2152
2153 /* If this is an international message we need the host to speak SMTPUTF8 */
2154 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2155 {
2156 errno = ERRNO_UTF8_FWD;
2157 goto RESPONSE_FAILED;
2158 }
2159 #endif
2160
2161 return OK;
2162
2163
2164 {
2165 int code;
2166
2167 RESPONSE_FAILED:
2168 message = NULL;
2169 sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
2170 sx->buffer, &code, &message, &pass_message);
2171 goto FAILED;
2172
2173 SEND_FAILED:
2174 code = '4';
2175 message = US string_sprintf("send() to %s [%s] failed: %s",
2176 sx->host->name, sx->host->address, strerror(errno));
2177 sx->send_quit = FALSE;
2178 goto FAILED;
2179
2180 EHLOHELO_FAILED:
2181 code = '4';
2182 message = string_sprintf("Remote host closed connection in response to %s"
2183 " (EHLO response was: %s)", smtp_command, sx->buffer);
2184 sx->send_quit = FALSE;
2185 goto FAILED;
2186
2187 /* This label is jumped to directly when a TLS negotiation has failed,
2188 or was not done for a host for which it is required. Values will be set
2189 in message and errno, and setting_up will always be true. Treat as
2190 a temporary error. */
2191
2192 #ifdef SUPPORT_TLS
2193 TLS_FAILED:
2194 code = '4';
2195 goto FAILED;
2196 #endif
2197
2198 /* The failure happened while setting up the call; see if the failure was
2199 a 5xx response (this will either be on connection, or following HELO - a 5xx
2200 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2201 fail all addresses, as this host is never going to accept them. For other
2202 errors during setting up (timeouts or whatever), defer all addresses, and
2203 yield DEFER, so that the host is not tried again for a while.
2204
2205 XXX This peeking for another host feels like a layering violation. We want
2206 to note the host as unusable, but down here we shouldn't know if this was
2207 the last host to try for the addr(list). Perhaps the upper layer should be
2208 the one to do set_errno() ? The problem is that currently the addr is where
2209 errno etc. are stashed, but until we run out of hosts to try the errors are
2210 host-specific. Maybe we should enhance the host_item definition? */
2211
2212 FAILED:
2213 sx->ok = FALSE; /* For when reached by GOTO */
2214 set_errno(sx->addrlist, errno, message,
2215 sx->host->next
2216 ? DEFER
2217 : code == '5'
2218 #ifdef SUPPORT_I18N
2219 || errno == ERRNO_UTF8_FWD
2220 #endif
2221 ? FAIL : DEFER,
2222 pass_message, sx->host
2223 #ifdef EXPERIMENTAL_DSN_INFO
2224 , sx->smtp_greeting, sx->helo_response
2225 #endif
2226 );
2227 yield = DEFER;
2228 }
2229
2230
2231 SEND_QUIT:
2232
2233 if (sx->send_quit)
2234 (void)smtp_write_command(&sx->outblock, SCMD_FLUSH, "QUIT\r\n");
2235
2236 #ifdef SUPPORT_TLS
2237 tls_close(FALSE, TRUE);
2238 #endif
2239
2240 /* Close the socket, and return the appropriate value, first setting
2241 works because the NULL setting is passed back to the calling process, and
2242 remote_max_parallel is forced to 1 when delivering over an existing connection,
2243 */
2244
2245 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2246 if (sx->send_quit)
2247 {
2248 shutdown(sx->outblock.sock, SHUT_WR);
2249 if (fcntl(sx->inblock.sock, F_SETFL, O_NONBLOCK) == 0)
2250 for (rc = 16; read(sx->inblock.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && rc > 0;)
2251 rc--; /* drain socket */
2252 sx->send_quit = FALSE;
2253 }
2254 (void)close(sx->inblock.sock);
2255 sx->inblock.sock = sx->outblock.sock = -1;
2256
2257 #ifndef DISABLE_EVENT
2258 (void) event_raise(sx->tblock->event_action, US"tcp:close", NULL);
2259 #endif
2260
2261 continue_transport = NULL;
2262 continue_hostname = NULL;
2263 return yield;
2264 }
2265
2266
2267
2268
2269 /* Create the string of options that will be appended to the MAIL FROM:
2270 in the connection context buffer */
2271
2272 static int
2273 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2274 {
2275 uschar * p = sx->buffer;
2276 address_item * addr;
2277 int address_count;
2278
2279 *p = 0;
2280
2281 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2282 send it, adding something to the message size to allow for imprecision
2283 and things that get added en route. Exim keeps the number of lines
2284 in a message, so we can give an accurate value for the original message, but we
2285 need some additional to handle added headers. (Double "." characters don't get
2286 included in the count.) */
2287
2288 if ( message_size > 0
2289 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
2290 {
2291 /*XXX problem here under spool_files_wireformat?
2292 Or just forget about lines? Or inflate by a fixed proportion? */
2293
2294 sprintf(CS p, " SIZE=%d", message_size+message_linecount+sx->ob->size_addition);
2295 while (*p) p++;
2296 }
2297
2298 #ifndef DISABLE_PRDR
2299 /* If it supports Per-Recipient Data Reponses, and we have omre than one recipient,
2300 request that */
2301
2302 sx->prdr_active = FALSE;
2303 if (sx->peer_offered & OPTION_PRDR)
2304 for (addr = addrlist; addr; addr = addr->next)
2305 if (addr->transport_return == PENDING_DEFER)
2306 {
2307 for (addr = addr->next; addr; addr = addr->next)
2308 if (addr->transport_return == PENDING_DEFER)
2309 { /* at least two recipients to send */
2310 sx->prdr_active = TRUE;
2311 sprintf(CS p, " PRDR"); p += 5;
2312 break;
2313 }
2314 break;
2315 }
2316 #endif
2317
2318 #ifdef SUPPORT_I18N
2319 /* If it supports internationalised messages, and this meesage need that,
2320 request it */
2321
2322 if ( sx->peer_offered & OPTION_UTF8
2323 && addrlist->prop.utf8_msg
2324 && !addrlist->prop.utf8_downcvt
2325 )
2326 Ustrcpy(p, " SMTPUTF8"), p += 9;
2327 #endif
2328
2329 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
2330 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
2331 addr && address_count < sx->max_rcpt;
2332 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2333 {
2334 address_count++;
2335 if (!(addr->dsn_flags & rf_dsnlasthop))
2336 {
2337 sx->dsn_all_lasthop = FALSE;
2338 break;
2339 }
2340 }
2341
2342 /* Add any DSN flags to the mail command */
2343
2344 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
2345 {
2346 if (dsn_ret == dsn_ret_hdrs)
2347 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2348 else if (dsn_ret == dsn_ret_full)
2349 { Ustrcpy(p, " RET=FULL"); p += 9; }
2350
2351 if (dsn_envid)
2352 {
2353 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
2354 while (*p) p++;
2355 }
2356 }
2357
2358 /* If an authenticated_sender override has been specified for this transport
2359 instance, expand it. If the expansion is forced to fail, and there was already
2360 an authenticated_sender for this message, the original value will be used.
2361 Other expansion failures are serious. An empty result is ignored, but there is
2362 otherwise no check - this feature is expected to be used with LMTP and other
2363 cases where non-standard addresses (e.g. without domains) might be required. */
2364
2365 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->ob))
2366 return ERROR;
2367
2368 return OK;
2369 }
2370
2371
2372 static void
2373 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
2374 {
2375 uschar * p = sx->buffer;
2376 *p = 0;
2377
2378 /* Add any DSN flags to the rcpt command */
2379
2380 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2381 {
2382 if (addr->dsn_flags & rf_dsnflags)
2383 {
2384 int i;
2385 BOOL first = TRUE;
2386
2387 Ustrcpy(p, " NOTIFY=");
2388 while (*p) p++;
2389 for (i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
2390 {
2391 if (!first) *p++ = ',';
2392 first = FALSE;
2393 Ustrcpy(p, rf_names[i]);
2394 while (*p) p++;
2395 }
2396 }
2397
2398 if (addr->dsn_orcpt)
2399 {
2400 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
2401 addr->dsn_orcpt);
2402 while (*p) p++;
2403 }
2404 }
2405 }
2406
2407
2408
2409 /*
2410 Return:
2411 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
2412 -1 MAIL response error
2413 -2 any non-MAIL read i/o error
2414 -3 non-MAIL response timeout
2415 -4 internal error; channel still usable
2416 -5 transmit failed
2417 */
2418
2419 int
2420 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
2421 {
2422 address_item * addr;
2423 int address_count;
2424 int rc;
2425
2426 if (build_mailcmd_options(sx, sx->first_addr) != OK)
2427 {
2428 *yield = ERROR;
2429 return -4;
2430 }
2431
2432 /* From here until we send the DATA command, we can make use of PIPELINING
2433 if the server host supports it. The code has to be able to check the responses
2434 at any point, for when the buffer fills up, so we write it totally generally.
2435 When PIPELINING is off, each command written reports that it has flushed the
2436 buffer. */
2437
2438 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
2439
2440 {
2441 uschar * s = sx->from_addr;
2442 #ifdef SUPPORT_I18N
2443 uschar * errstr = NULL;
2444
2445 /* If we must downconvert, do the from-address here. Remember we had to
2446 for the to-addresses (done below), and also (ugly) for re-doing when building
2447 the delivery log line. */
2448
2449 if ( sx->addrlist->prop.utf8_msg
2450 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
2451 )
2452 {
2453 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
2454 {
2455 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2456 *yield = ERROR;
2457 return -4;
2458 }
2459 setflag(sx->addrlist, af_utf8_downcvt);
2460 }
2461 #endif
2462
2463 rc = smtp_write_command(&sx->outblock, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
2464 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
2465 }
2466
2467 mail_command = string_copy(big_buffer); /* Save for later error message */
2468
2469 switch(rc)
2470 {
2471 case -1: /* Transmission error */
2472 return -5;
2473
2474 case +1: /* Cmd was sent */
2475 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
2476 sx->ob->command_timeout))
2477 {
2478 if (errno == 0 && sx->buffer[0] == '4')
2479 {
2480 errno = ERRNO_MAIL4XX;
2481 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2482 }
2483 return -1;
2484 }
2485 sx->pending_MAIL = FALSE;
2486 break;
2487
2488 /* otherwise zero: command queued for pipeline */
2489 }
2490
2491 /* Pass over all the relevant recipient addresses for this host, which are the
2492 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2493 several before we have to read the responses for those seen so far. This
2494 checking is done by a subroutine because it also needs to be done at the end.
2495 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
2496 the next one if not all are sent.
2497
2498 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2499 last address because we want to abort if any recipients have any kind of
2500 problem, temporary or permanent. We know that all recipient addresses will have
2501 the PENDING_DEFER status, because only one attempt is ever made, and we know
2502 that max_rcpt will be large, so all addresses will be done at once.
2503
2504 For verify we flush the pipeline after any (the only) rcpt address. */
2505
2506 for (addr = sx->first_addr, address_count = 0;
2507 addr && address_count < sx->max_rcpt;
2508 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2509 {
2510 int count;
2511 BOOL no_flush;
2512 uschar * rcpt_addr;
2513
2514 if (tcp_out_fastopen && !tcp_out_fastopen_logged)
2515 {
2516 setflag(addr, af_tcp_fastopen_conn);
2517 if (tcp_out_fastopen > 1) setflag(addr, af_tcp_fastopen);
2518 }
2519
2520 addr->dsn_aware = sx->peer_offered & OPTION_DSN
2521 ? dsn_support_yes : dsn_support_no;
2522
2523 address_count++;
2524 no_flush = pipelining_active && !sx->verify
2525 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
2526
2527 build_rcptcmd_options(sx, addr);
2528
2529 /* Now send the RCPT command, and process outstanding responses when
2530 necessary. After a timeout on RCPT, we just end the function, leaving the
2531 yield as OK, because this error can often mean that there is a problem with
2532 just one address, so we don't want to delay the host. */
2533
2534 rcpt_addr = transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes);
2535
2536 #ifdef SUPPORT_I18N
2537 if ( testflag(sx->addrlist, af_utf8_downcvt)
2538 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
2539 )
2540 {
2541 /*XXX could we use a per-address errstr here? Not fail the whole send? */
2542 errno = ERRNO_EXPANDFAIL;
2543 return -5; /*XXX too harsh? */
2544 }
2545 #endif
2546
2547 count = smtp_write_command(&sx->outblock, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
2548 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
2549
2550 if (count < 0) return -5;
2551 if (count > 0)
2552 {
2553 switch(sync_responses(sx, count, 0))
2554 {
2555 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
2556 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2557 break;
2558
2559 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2560 if (!sx->lmtp) /* can't tell about progress yet */
2561 sx->completed_addr = TRUE;
2562 case 0: /* No 2xx or 5xx, but no probs */
2563 break;
2564
2565 case -1: return -3; /* Timeout on RCPT */
2566 case -2: return -2; /* non-MAIL read i/o error */
2567 default: return -1; /* any MAIL error */
2568 }
2569 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
2570 }
2571 } /* Loop for next address */
2572
2573 tcp_out_fastopen_logged = TRUE;
2574 sx->next_addr = addr;
2575 return 0;
2576 }
2577
2578
2579 #ifdef SUPPORT_TLS
2580 /*****************************************************
2581 * Proxy TLS connection for another transport process *
2582 ******************************************************/
2583 /*
2584 Close the unused end of the pipe, fork once more, then use the given buffer
2585 as a staging area, and select on both the given fd and the TLS'd client-fd for
2586 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
2587 Do blocking full-size writes, and reads under a timeout. Once both input
2588 channels are closed, exit the process.
2589
2590 Arguments:
2591 buf space to use for buffering
2592 bufsiz size of buffer
2593 pfd pipe filedescriptor array; [0] is comms to proxied process
2594 timeout per-read timeout, seconds
2595 */
2596
2597 void
2598 smtp_proxy_tls(uschar * buf, size_t bsize, int * pfd, int timeout)
2599 {
2600 fd_set rfds, efds;
2601 int max_fd = MAX(pfd[0], tls_out.active) + 1;
2602 int rc, i, fd_bits, nbytes;
2603
2604 close(pfd[1]);
2605 if ((rc = fork()))
2606 {
2607 DEBUG(D_transport) debug_printf("proxy-proc final-pid %d\n", rc);
2608 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
2609 }
2610
2611 if (running_in_test_harness) millisleep(100); /* let parent debug out */
2612 set_process_info("proxying TLS connection for continued transport");
2613 FD_ZERO(&rfds);
2614 FD_SET(tls_out.active, &rfds);
2615 FD_SET(pfd[0], &rfds);
2616
2617 for (fd_bits = 3; fd_bits; )
2618 {
2619 time_t time_left = timeout;
2620 time_t time_start = time(NULL);
2621
2622 /* wait for data */
2623 efds = rfds;
2624 do
2625 {
2626 struct timeval tv = { time_left, 0 };
2627
2628 rc = select(max_fd,
2629 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
2630
2631 if (rc < 0 && errno == EINTR)
2632 if ((time_left -= time(NULL) - time_start) > 0) continue;
2633
2634 if (rc <= 0)
2635 {
2636 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
2637 goto done;
2638 }
2639
2640 if (FD_ISSET(tls_out.active, &efds) || FD_ISSET(pfd[0], &efds))
2641 {
2642 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
2643 FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
2644 goto done;
2645 }
2646 }
2647 while (rc < 0 || !(FD_ISSET(tls_out.active, &rfds) || FD_ISSET(pfd[0], &rfds)));
2648
2649 /* handle inbound data */
2650 if (FD_ISSET(tls_out.active, &rfds))
2651 if ((rc = tls_read(FALSE, buf, bsize)) <= 0)
2652 {
2653 fd_bits &= ~1;
2654 FD_CLR(tls_out.active, &rfds);
2655 shutdown(pfd[0], SHUT_WR);
2656 timeout = 5;
2657 }
2658 else
2659 {
2660 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2661 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
2662 }
2663 else if (fd_bits & 1)
2664 FD_SET(tls_out.active, &rfds);
2665
2666 /* handle outbound data */
2667 if (FD_ISSET(pfd[0], &rfds))
2668 if ((rc = read(pfd[0], buf, bsize)) <= 0)
2669 {
2670 fd_bits = 0;
2671 tls_close(FALSE, TRUE);
2672 }
2673 else
2674 {
2675 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2676 if ((i = tls_write(FALSE, buf + nbytes, rc - nbytes, FALSE)) < 0)
2677 goto done;
2678 }
2679 else if (fd_bits & 2)
2680 FD_SET(pfd[0], &rfds);
2681 }
2682
2683 done:
2684 if (running_in_test_harness) millisleep(100); /* let logging complete */
2685 exim_exit(0, US"TLS proxy");
2686 }
2687 #endif
2688
2689
2690 /*************************************************
2691 * Deliver address list to given host *
2692 *************************************************/
2693
2694 /* If continue_hostname is not null, we get here only when continuing to
2695 deliver down an existing channel. The channel was passed as the standard
2696 input. TLS is never active on a passed channel; the previous process always
2697 closes it down before passing the connection on.
2698
2699 Otherwise, we have to make a connection to the remote host, and do the
2700 initial protocol exchange.
2701
2702 When running as an MUA wrapper, if the sender or any recipient is rejected,
2703 temporarily or permanently, we force failure for all recipients.
2704
2705 Arguments:
2706 addrlist chain of potential addresses to deliver; only those whose
2707 transport_return field is set to PENDING_DEFER are currently
2708 being processed; others should be skipped - they have either
2709 been delivered to an earlier host or IP address, or been
2710 failed by one of them.
2711 host host to deliver to
2712 host_af AF_INET or AF_INET6
2713 defport default TCP/IP port to use if host does not specify, in host
2714 byte order
2715 interface interface to bind to, or NULL
2716 tblock transport instance block
2717 message_defer set TRUE if yield is OK, but all addresses were deferred
2718 because of a non-recipient, non-host failure, that is, a
2719 4xx response to MAIL FROM, DATA, or ".". This is a defer
2720 that is specific to the message.
2721 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2722 a second attempt after TLS initialization fails
2723
2724 Returns: OK - the connection was made and the delivery attempted;
2725 the result for each address is in its data block.
2726 DEFER - the connection could not be made, or something failed
2727 while setting up the SMTP session, or there was a
2728 non-message-specific error, such as a timeout.
2729 ERROR - a filter command is specified for this transport,
2730 and there was a problem setting it up; OR helo_data
2731 or add_headers or authenticated_sender is specified
2732 for this transport, and the string failed to expand
2733 */
2734
2735 static int
2736 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
2737 uschar *interface, transport_instance *tblock,
2738 BOOL *message_defer, BOOL suppress_tls)
2739 {
2740 address_item *addr;
2741 int yield = OK;
2742 int save_errno;
2743 int rc;
2744 struct timeval start_delivery_time;
2745
2746 BOOL pass_message = FALSE;
2747 uschar *message = NULL;
2748 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
2749
2750 smtp_context sx;
2751
2752 gettimeofday(&start_delivery_time, NULL);
2753 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
2754 *message_defer = FALSE;
2755
2756 sx.addrlist = addrlist;
2757 sx.host = host;
2758 sx.host_af = host_af,
2759 sx.port = defport;
2760 sx.interface = interface;
2761 sx.helo_data = NULL;
2762 sx.tblock = tblock;
2763 sx.verify = FALSE;
2764
2765 /* Get the channel set up ready for a message (MAIL FROM being the next
2766 SMTP command to send */
2767
2768 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
2769 return rc;
2770
2771 /* If there is a filter command specified for this transport, we can now
2772 set it up. This cannot be done until the identify of the host is known. */
2773
2774 if (tblock->filter_command)
2775 {
2776 transport_filter_timeout = tblock->filter_timeout;
2777
2778 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2779 yield ERROR. */
2780
2781 if (!transport_set_up_command(&transport_filter_argv,
2782 tblock->filter_command, TRUE, DEFER, addrlist,
2783 string_sprintf("%.50s transport", tblock->name), NULL))
2784 {
2785 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2786 FALSE);
2787 yield = ERROR;
2788 goto SEND_QUIT;
2789 }
2790
2791 if ( transport_filter_argv
2792 && *transport_filter_argv
2793 && **transport_filter_argv
2794 && sx.peer_offered & OPTION_CHUNKING
2795 )
2796 {
2797 sx.peer_offered &= ~OPTION_CHUNKING;
2798 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2799 }
2800 }
2801
2802 sx.first_addr = addrlist;
2803
2804 /* For messages that have more than the maximum number of envelope recipients,
2805 we want to send several transactions down the same SMTP connection. (See
2806 comments in deliver.c as to how this reconciles, heuristically, with
2807 remote_max_parallel.) This optimization was added to Exim after the following
2808 code was already working. The simplest way to put it in without disturbing the
2809 code was to use a goto to jump back to this point when there is another
2810 transaction to handle. */
2811
2812 SEND_MESSAGE:
2813 sx.from_addr = return_path;
2814 sx.sync_addr = sx.first_addr;
2815 sx.ok = FALSE;
2816 sx.send_rset = TRUE;
2817 sx.completed_addr = FALSE;
2818
2819
2820 /* If we are a continued-connection-after-verify the MAIL and RCPT
2821 commands were already sent; do not re-send but do mark the addrs as
2822 having been accepted up to RCPT stage. A traditional cont-conn
2823 always has a sequence number greater than one. */
2824
2825 if (continue_hostname && continue_sequence == 1)
2826 {
2827 address_item * addr;
2828
2829 sx.peer_offered = smtp_peer_options;
2830 sx.pending_MAIL = FALSE;
2831 sx.ok = TRUE;
2832 sx.next_addr = NULL;
2833
2834 for (addr = addrlist; addr; addr = addr->next)
2835 addr->transport_return = PENDING_OK;
2836 }
2837 else
2838 {
2839 /* Initiate a message transfer. */
2840
2841 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
2842 {
2843 case 0: break;
2844 case -1: case -2: goto RESPONSE_FAILED;
2845 case -3: goto END_OFF;
2846 case -4: goto SEND_QUIT;
2847 default: goto SEND_FAILED;
2848 }
2849
2850 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2851 permanently or temporarily. We should have flushed and synced after the last
2852 RCPT. */
2853
2854 if (mua_wrapper)
2855 {
2856 address_item * a;
2857 unsigned cnt;
2858
2859 for (a = sx.first_addr, cnt = 0; a && cnt < sx.max_rcpt; a = a->next, cnt++)
2860 if (a->transport_return != PENDING_OK)
2861 {
2862 /*XXX could we find a better errno than 0 here? */
2863 set_errno_nohost(addrlist, 0, a->message, FAIL,
2864 testflag(a, af_pass_message));
2865 sx.ok = FALSE;
2866 break;
2867 }
2868 }
2869 }
2870
2871 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2872 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2873 have a good recipient buffered up if we are pipelining. We don't want to waste
2874 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2875 are pipelining. The responses are all handled by sync_responses().
2876 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2877 to send is. */
2878
2879 if ( !(sx.peer_offered & OPTION_CHUNKING)
2880 && (sx.ok || (pipelining_active && !mua_wrapper)))
2881 {
2882 int count = smtp_write_command(&sx.outblock, SCMD_FLUSH, "DATA\r\n");
2883
2884 if (count < 0) goto SEND_FAILED;
2885 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
2886 {
2887 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2888 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2889 break;
2890
2891 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2892 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2893 case 0: break; /* No 2xx or 5xx, but no probs */
2894
2895 case -1: goto END_OFF; /* Timeout on RCPT */
2896 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2897 }
2898 pipelining_active = FALSE;
2899 data_command = string_copy(big_buffer); /* Save for later error message */
2900 }
2901
2902 /* If there were no good recipients (but otherwise there have been no
2903 problems), just set ok TRUE, since we have handled address-specific errors
2904 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2905 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2906 well as body. Set the appropriate timeout value to be used for each chunk.
2907 (Haven't been able to make it work using select() for writing yet.) */
2908
2909 if (!(sx.peer_offered & OPTION_CHUNKING) && !sx.ok)
2910 {
2911 /* Save the first address of the next batch. */
2912 sx.first_addr = sx.next_addr;
2913
2914 sx.ok = TRUE;
2915 }
2916 else
2917 {
2918 transport_ctx tctx = {
2919 {sx.inblock.sock},
2920 tblock,
2921 addrlist,
2922 US".", US"..", /* Escaping strings */
2923 topt_use_crlf | topt_escape_headers
2924 | (tblock->body_only ? topt_no_headers : 0)
2925 | (tblock->headers_only ? topt_no_body : 0)
2926 | (tblock->return_path_add ? topt_add_return_path : 0)
2927 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2928 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2929 };
2930
2931 /* If using CHUNKING we need a callback from the generic transport
2932 support to us, for the sending of BDAT smtp commands and the reaping
2933 of responses. The callback needs a whole bunch of state so set up
2934 a transport-context structure to be passed around. */
2935
2936 if (sx.peer_offered & OPTION_CHUNKING)
2937 {
2938 tctx.check_string = tctx.escape_string = NULL;
2939 tctx.options |= topt_use_bdat;
2940 tctx.chunk_cb = smtp_chunk_cmd_callback;
2941 sx.pending_BDAT = FALSE;
2942 sx.good_RCPT = sx.ok;
2943 sx.cmd_count = 0;
2944 tctx.smtp_context = &sx;
2945 }
2946 else
2947 tctx.options |= topt_end_dot;
2948
2949 /* Save the first address of the next batch. */
2950 sx.first_addr = sx.next_addr;
2951
2952 /* Responses from CHUNKING commands go in buffer. Otherwise,
2953 there has not been a response. */
2954
2955 sx.buffer[0] = 0;
2956
2957 sigalrm_seen = FALSE;
2958 transport_write_timeout = sx.ob->data_timeout;
2959 smtp_command = US"sending data block"; /* For error messages */
2960 DEBUG(D_transport|D_v)
2961 if (sx.peer_offered & OPTION_CHUNKING)
2962 debug_printf(" will write message using CHUNKING\n");
2963 else
2964 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2965 transport_count = 0;
2966
2967 #ifndef DISABLE_DKIM
2968 sx.ok = dkim_transport_write_message(&tctx, &sx.ob->dkim, CUSS &message);
2969 #else
2970 sx.ok = transport_write_message(&tctx, 0);
2971 #endif
2972
2973 /* transport_write_message() uses write() because it is called from other
2974 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2975 it can exit with "Broken pipe" as its error. This really means that the
2976 socket got closed at the far end. */
2977
2978 transport_write_timeout = 0; /* for subsequent transports */
2979
2980 /* Failure can either be some kind of I/O disaster (including timeout),
2981 or the failure of a transport filter or the expansion of added headers.
2982 Or, when CHUNKING, it can be a protocol-detected failure. */
2983
2984 if (!sx.ok)
2985 if (message) goto SEND_FAILED;
2986 else goto RESPONSE_FAILED;
2987
2988 /* We used to send the terminating "." explicitly here, but because of
2989 buffering effects at both ends of TCP/IP connections, you don't gain
2990 anything by keeping it separate, so it might as well go in the final
2991 data buffer for efficiency. This is now done by setting the topt_end_dot
2992 flag above. */
2993
2994 smtp_command = US"end of data";
2995
2996 if (sx.peer_offered & OPTION_CHUNKING && sx.cmd_count > 1)
2997 {
2998 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2999 switch(sync_responses(&sx, sx.cmd_count-1, 0))
3000 {
3001 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3002 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3003 break;
3004
3005 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3006 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3007 case 0: break; /* No 2xx or 5xx, but no probs */
3008
3009 case -1: goto END_OFF; /* Timeout on RCPT */
3010 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3011 }
3012 }
3013
3014 #ifndef DISABLE_PRDR
3015 /* For PRDR we optionally get a partial-responses warning
3016 * followed by the individual responses, before going on with
3017 * the overall response. If we don't get the warning then deal
3018 * with per non-PRDR. */
3019 if(sx.prdr_active)
3020 {
3021 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '3',
3022 sx.ob->final_timeout);
3023 if (!sx.ok && errno == 0) switch(sx.buffer[0])
3024 {
3025 case '2': sx.prdr_active = FALSE;
3026 sx.ok = TRUE;
3027 break;
3028 case '4': errno = ERRNO_DATA4XX;
3029 addrlist->more_errno |=
3030 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3031 break;
3032 }
3033 }
3034 else
3035 #endif
3036
3037 /* For non-PRDR SMTP, we now read a single response that applies to the
3038 whole message. If it is OK, then all the addresses have been delivered. */
3039
3040 if (!sx.lmtp)
3041 {
3042 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3043 sx.ob->final_timeout);
3044 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
3045 {
3046 errno = ERRNO_DATA4XX;
3047 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3048 }
3049 }
3050
3051 /* For LMTP, we get back a response for every RCPT command that we sent;
3052 some may be accepted and some rejected. For those that get a response, their
3053 status is fixed; any that are accepted have been handed over, even if later
3054 responses crash - at least, that's how I read RFC 2033.
3055
3056 If all went well, mark the recipient addresses as completed, record which
3057 host/IPaddress they were delivered to, and cut out RSET when sending another
3058 message down the same channel. Write the completed addresses to the journal
3059 now so that they are recorded in case there is a crash of hardware or
3060 software before the spool gets updated. Also record the final SMTP
3061 confirmation if needed (for SMTP only). */
3062
3063 if (sx.ok)
3064 {
3065 int flag = '=';
3066 struct timeval delivery_time;
3067 int len;
3068 uschar * conf = NULL;
3069
3070 timesince(&delivery_time, &start_delivery_time);
3071 sx.send_rset = FALSE;
3072 pipelining_active = FALSE;
3073
3074 /* Set up confirmation if needed - applies only to SMTP */
3075
3076 if (
3077 #ifdef DISABLE_EVENT
3078 LOGGING(smtp_confirmation) &&
3079 #endif
3080 !sx.lmtp
3081 )
3082 {
3083 const uschar *s = string_printing(sx.buffer);
3084 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3085 conf = (s == sx.buffer)? US string_copy(s) : US s;
3086 }
3087
3088 /* Process all transported addresses - for LMTP or PRDR, read a status for
3089 each one. */
3090
3091 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3092 {
3093 if (addr->transport_return != PENDING_OK) continue;
3094
3095 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3096 remaining addresses. Otherwise, it's a return code for just the one
3097 address. For temporary errors, add a retry item for the address so that
3098 it doesn't get tried again too soon. */
3099
3100 #ifndef DISABLE_PRDR
3101 if (sx.lmtp || sx.prdr_active)
3102 #else
3103 if (sx.lmtp)
3104 #endif
3105 {
3106 if (!smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3107 sx.ob->final_timeout))
3108 {
3109 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3110 addr->message = string_sprintf(
3111 #ifndef DISABLE_PRDR
3112 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3113 #else
3114 "LMTP error after %s: %s",
3115 #endif
3116 data_command, string_printing(sx.buffer));
3117 setflag(addr, af_pass_message); /* Allow message to go to user */
3118 if (sx.buffer[0] == '5')
3119 addr->transport_return = FAIL;
3120 else
3121 {
3122 errno = ERRNO_DATA4XX;
3123 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3124 addr->transport_return = DEFER;
3125 #ifndef DISABLE_PRDR
3126 if (!sx.prdr_active)
3127 #endif
3128 retry_add_item(addr, addr->address_retry_key, 0);
3129 }
3130 continue;
3131 }
3132 sx.completed_addr = TRUE; /* NOW we can set this flag */
3133 if (LOGGING(smtp_confirmation))
3134 {
3135 const uschar *s = string_printing(sx.buffer);
3136 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3137 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3138 }
3139 }
3140
3141 /* SMTP, or success return from LMTP for this address. Pass back the
3142 actual host that was used. */
3143
3144 addr->transport_return = OK;
3145 addr->more_errno = delivery_time.tv_sec;
3146 addr->delivery_usec = delivery_time.tv_usec;
3147 addr->host_used = host;
3148 addr->special_action = flag;
3149 addr->message = conf;
3150 #ifndef DISABLE_PRDR
3151 if (sx.prdr_active) setflag(addr, af_prdr_used);
3152 #endif
3153 if (sx.peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
3154 flag = '-';
3155
3156 #ifndef DISABLE_PRDR
3157 if (!sx.prdr_active)
3158 #endif
3159 {
3160 /* Update the journal. For homonymic addresses, use the base address plus
3161 the transport name. See lots of comments in deliver.c about the reasons
3162 for the complications when homonyms are involved. Just carry on after
3163 write error, as it may prove possible to update the spool file later. */
3164
3165 if (testflag(addr, af_homonym))
3166 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3167 else
3168 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3169
3170 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3171 len = Ustrlen(CS sx.buffer);
3172 if (write(journal_fd, sx.buffer, len) != len)
3173 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3174 "%s: %s", sx.buffer, strerror(errno));
3175 }
3176 }
3177
3178 #ifndef DISABLE_PRDR
3179 if (sx.prdr_active)
3180 {
3181 /* PRDR - get the final, overall response. For any non-success
3182 upgrade all the address statuses. */
3183 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3184 sx.ob->final_timeout);
3185 if (!sx.ok)
3186 {
3187 if(errno == 0 && sx.buffer[0] == '4')
3188 {
3189 errno = ERRNO_DATA4XX;
3190 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3191 }
3192 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3193 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3194 addr->transport_return = PENDING_OK; /* allow set_errno action */
3195 goto RESPONSE_FAILED;
3196 }
3197
3198 /* Update the journal, or setup retry. */
3199 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3200 if (addr->transport_return == OK)
3201 {
3202 if (testflag(addr, af_homonym))
3203 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3204 else
3205 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3206
3207 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3208 len = Ustrlen(CS sx.buffer);
3209 if (write(journal_fd, sx.buffer, len) != len)
3210 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3211 "%s: %s", sx.buffer, strerror(errno));
3212 }
3213 else if (addr->transport_return == DEFER)
3214 retry_add_item(addr, addr->address_retry_key, -2);
3215 }
3216 #endif
3217
3218 /* Ensure the journal file is pushed out to disk. */
3219
3220 if (EXIMfsync(journal_fd) < 0)
3221 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3222 strerror(errno));
3223 }
3224 }
3225
3226
3227 /* Handle general (not specific to one address) failures here. The value of ok
3228 is used to skip over this code on the falling through case. A timeout causes a
3229 deferral. Other errors may defer or fail according to the response code, and
3230 may set up a special errno value, e.g. after connection chopped, which is
3231 assumed if errno == 0 and there is no text in the buffer. If control reaches
3232 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3233 the problem is not related to this specific message. */
3234
3235 if (!sx.ok)
3236 {
3237 int code, set_rc;
3238 uschar * set_message;
3239
3240 RESPONSE_FAILED:
3241 {
3242 save_errno = errno;
3243 message = NULL;
3244 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3245 sx.buffer, &code, &message, &pass_message);
3246 goto FAILED;
3247 }
3248
3249 SEND_FAILED:
3250 {
3251 save_errno = errno;
3252 code = '4';
3253 message = string_sprintf("send() to %s [%s] failed: %s",
3254 host->name, host->address, message ? message : US strerror(save_errno));
3255 sx.send_quit = FALSE;
3256 goto FAILED;
3257 }
3258
3259 FAILED:
3260 {
3261 BOOL message_error;
3262
3263 sx.ok = FALSE; /* For when reached by GOTO */
3264 set_message = message;
3265
3266 /* We want to handle timeouts after MAIL or "." and loss of connection after
3267 "." specially. They can indicate a problem with the sender address or with
3268 the contents of the message rather than a real error on the connection. These
3269 cases are treated in the same way as a 4xx response. This next bit of code
3270 does the classification. */
3271
3272 switch(save_errno)
3273 {
3274 case 0:
3275 case ERRNO_MAIL4XX:
3276 case ERRNO_DATA4XX:
3277 message_error = TRUE;
3278 break;
3279
3280 case ETIMEDOUT:
3281 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
3282 Ustrncmp(smtp_command,"end ",4) == 0;
3283 break;
3284
3285 case ERRNO_SMTPCLOSED:
3286 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
3287 break;
3288
3289 default:
3290 message_error = FALSE;
3291 break;
3292 }
3293
3294 /* Handle the cases that are treated as message errors. These are:
3295
3296 (a) negative response or timeout after MAIL
3297 (b) negative response after DATA
3298 (c) negative response or timeout or dropped connection after "."
3299 (d) utf8 support required and not offered
3300
3301 It won't be a negative response or timeout after RCPT, as that is dealt
3302 with separately above. The action in all cases is to set an appropriate
3303 error code for all the addresses, but to leave yield set to OK because the
3304 host itself has not failed. Of course, it might in practice have failed
3305 when we've had a timeout, but if so, we'll discover that at the next
3306 delivery attempt. For a temporary error, set the message_defer flag, and
3307 write to the logs for information if this is not the last host. The error
3308 for the last host will be logged as part of the address's log line. */
3309
3310 if (message_error)
3311 {
3312 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
3313
3314 /* If there's an errno, the message contains just the identity of
3315 the host. */
3316
3317 if (code == '5')
3318 set_rc = FAIL;
3319 else /* Anything other than 5 is treated as temporary */
3320 {
3321 set_rc = DEFER;
3322 if (save_errno > 0)
3323 message = US string_sprintf("%s: %s", message, strerror(save_errno));
3324
3325 write_logs(host, message, sx.first_addr ? sx.first_addr->basic_errno : 0);
3326
3327 *message_defer = TRUE;
3328 }
3329 }
3330
3331 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
3332 ".", or some other transportation error. We defer all addresses and yield
3333 DEFER, except for the case of failed add_headers expansion, or a transport
3334 filter failure, when the yield should be ERROR, to stop it trying other
3335 hosts. */
3336
3337 else
3338 {
3339 set_rc = DEFER;
3340 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
3341 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3342 }
3343 }
3344
3345 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3346 #ifdef EXPERIMENTAL_DSN_INFO
3347 , sx.smtp_greeting, sx.helo_response
3348 #endif
3349 );
3350 }
3351
3352
3353 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3354 SMTP session tidily. However, if there were too many addresses to send in one
3355 message (indicated by first_addr being non-NULL) we want to carry on with the
3356 rest of them. Also, it is desirable to send more than one message down the SMTP
3357 connection if there are several waiting, provided we haven't already sent so
3358 many as to hit the configured limit. The function transport_check_waiting looks
3359 for a waiting message and returns its id. Then transport_pass_socket tries to
3360 set up a continued delivery by passing the socket on to another process. The
3361 variable send_rset is FALSE if a message has just been successfully transfered.
3362
3363 If we are already sending down a continued channel, there may be further
3364 addresses not yet delivered that are aimed at the same host, but which have not
3365 been passed in this run of the transport. In this case, continue_more will be
3366 true, and all we should do is send RSET if necessary, and return, leaving the
3367 channel open.
3368
3369 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3370 do not want to continue with other messages down the same channel, because that
3371 can lead to looping between two or more messages, all with the same,
3372 temporarily failing address(es). [The retry information isn't updated yet, so
3373 new processes keep on trying.] We probably also don't want to try more of this
3374 message's addresses either.
3375
3376 If we have started a TLS session, we have to end it before passing the
3377 connection to a new process. However, not all servers can handle this (Exim
3378 can), so we do not pass such a connection on if the host matches
3379 hosts_nopass_tls. */
3380
3381 DEBUG(D_transport)
3382 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3383 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
3384 sx.send_rset, continue_more, yield, sx.first_addr ? "not " : "");
3385
3386 if (sx.completed_addr && sx.ok && sx.send_quit)
3387 {
3388 BOOL more;
3389 smtp_compare_t t_compare;
3390
3391 t_compare.tblock = tblock;
3392 t_compare.current_sender_address = sender_address;
3393
3394 if ( sx.first_addr != NULL
3395 || continue_more
3396 || (
3397 #ifdef SUPPORT_TLS
3398 ( tls_out.active < 0 && !continue_proxy_cipher
3399 || verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
3400 )
3401 &&
3402 #endif
3403 transport_check_waiting(tblock->name, host->name,
3404 tblock->connection_max_messages, new_message_id, &more,
3405 (oicf)smtp_are_same_identities, (void*)&t_compare)
3406 ) )
3407 {
3408 uschar *msg;
3409 BOOL pass_message;
3410
3411 if (sx.send_rset)
3412 if (! (sx.ok = smtp_write_command(&sx.outblock, SCMD_FLUSH, "RSET\r\n") >= 0))
3413 {
3414 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3415 host->address, strerror(errno));
3416 sx.send_quit = FALSE;
3417 }
3418 else if (! (sx.ok = smtp_read_response(&sx.inblock, sx.buffer,
3419 sizeof(sx.buffer), '2', sx.ob->command_timeout)))
3420 {
3421 int code;
3422 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
3423 &pass_message);
3424 if (!sx.send_quit)
3425 {
3426 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3427 host->name, host->address, msg);
3428 }
3429 }
3430
3431 /* Either RSET was not needed, or it succeeded */
3432
3433 if (sx.ok)
3434 {
3435 int pfd[2];
3436 int socket_fd = sx.inblock.sock;
3437
3438
3439 if (sx.first_addr != NULL) /* More addresses still to be sent */
3440 { /* in this run of the transport */
3441 continue_sequence++; /* Causes * in logging */
3442 goto SEND_MESSAGE;
3443 }
3444
3445 /* Unless caller said it already has more messages listed for this host,
3446 pass the connection on to a new Exim process (below, the call to
3447 transport_pass_socket). If the caller has more ready, just return with
3448 the connection still open. */
3449
3450 #ifdef SUPPORT_TLS
3451 if (tls_out.active >= 0)
3452 if ( continue_more
3453 || verify_check_given_host(&sx.ob->hosts_noproxy_tls, host) == OK)
3454 {
3455 /* Before passing the socket on, or returning to caller with it still
3456 open, we must shut down TLS. Not all MTAs allow for the continuation
3457 of the SMTP session when TLS is shut down. We test for this by sending
3458 a new EHLO. If we don't get a good response, we don't attempt to pass
3459 the socket on. */
3460
3461 tls_close(FALSE, TRUE);
3462 smtp_peer_options = smtp_peer_options_wrap;
3463 sx.ok = !sx.smtps
3464 && smtp_write_command(&sx.outblock, SCMD_FLUSH,
3465 "EHLO %s\r\n", sx.helo_data) >= 0
3466 && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
3467 '2', sx.ob->command_timeout);
3468
3469 if (sx.ok && continue_more)
3470 return yield; /* More addresses for another run */
3471 }
3472 else
3473 {
3474 /* Set up a pipe for proxying TLS for the new transport process */
3475
3476 smtp_peer_options |= OPTION_TLS;
3477 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
3478 socket_fd = pfd[1];
3479 else
3480 set_errno(sx.first_addr, errno, US"internal allocation problem",
3481 DEFER, FALSE, host
3482 # ifdef EXPERIMENTAL_DSN_INFO
3483 , sx.smtp_greeting, sx.helo_response
3484 # endif
3485 );
3486 }
3487 else
3488 #endif
3489 if (continue_more)
3490 return yield; /* More addresses for another run */
3491
3492 /* If the socket is successfully passed, we mustn't send QUIT (or
3493 indeed anything!) from here. */
3494
3495 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3496 propagate it from the initial
3497 */
3498 if (sx.ok && transport_pass_socket(tblock->name, host->name,
3499 host->address, new_message_id, socket_fd))
3500 {
3501 sx.send_quit = FALSE;
3502
3503 /* We have passed the client socket to a fresh transport process.
3504 If TLS is still active, we need to proxy it for the transport we
3505 just passed the baton to. Fork a child to to do it, and return to
3506 get logging done asap. Which way to place the work makes assumptions
3507 about post-fork prioritisation which may not hold on all platforms. */
3508 #ifdef SUPPORT_TLS
3509 if (tls_out.active >= 0)
3510 {
3511 int pid = fork();
3512 if (pid == 0) /* child; fork again to disconnect totally */
3513 {
3514 if (running_in_test_harness) millisleep(100); /* let parent debug out */
3515 /* does not return */
3516 smtp_proxy_tls(sx.buffer, sizeof(sx.buffer), pfd,
3517 sx.ob->command_timeout);
3518 }
3519
3520 if (pid > 0) /* parent */
3521 {
3522 DEBUG(D_transport) debug_printf("proxy-proc inter-pid %d\n", pid);
3523 close(pfd[0]);
3524 /* tidy the inter-proc to disconn the proxy proc */
3525 waitpid(pid, NULL, 0);
3526 tls_close(FALSE, FALSE);
3527 (void)close(sx.inblock.sock);
3528 continue_transport = NULL;
3529 continue_hostname = NULL;
3530 return yield;
3531 }
3532 log_write(0, LOG_PANIC_DIE, "fork failed");
3533 }
3534 #endif
3535 }
3536 }
3537
3538 /* If RSET failed and there are addresses left, they get deferred. */
3539 else
3540 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
3541 #ifdef EXPERIMENTAL_DSN_INFO
3542 , sx.smtp_greeting, sx.helo_response
3543 #endif
3544 );
3545 }
3546 }
3547
3548 /* End off tidily with QUIT unless the connection has died or the socket has
3549 been passed to another process. There has been discussion on the net about what
3550 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3551 to wait for a response, but on the other hand, there isn't anything one can do
3552 with an error response, other than log it. Exim used to do that. However,
3553 further discussion suggested that it is positively advantageous not to wait for
3554 the response, but to close the session immediately. This is supposed to move
3555 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3556 load from the server. (Hosts that are both servers and clients may not see much
3557 difference, of course.) Further discussion indicated that this was safe to do
3558 on Unix systems which have decent implementations of TCP/IP that leave the
3559 connection around for a while (TIME_WAIT) after the application has gone away.
3560 This enables the response sent by the server to be properly ACKed rather than
3561 timed out, as can happen on broken TCP/IP implementations on other OS.
3562
3563 This change is being made on 31-Jul-98. After over a year of trouble-free
3564 operation, the old commented-out code was removed on 17-Sep-99. */
3565
3566 SEND_QUIT:
3567 if (sx.send_quit) (void)smtp_write_command(&sx.outblock, SCMD_FLUSH, "QUIT\r\n");
3568
3569 END_OFF:
3570
3571 #ifdef SUPPORT_TLS
3572 tls_close(FALSE, TRUE);
3573 #endif
3574
3575 /* Close the socket, and return the appropriate value, first setting
3576 works because the NULL setting is passed back to the calling process, and
3577 remote_max_parallel is forced to 1 when delivering over an existing connection,
3578
3579 If all went well and continue_more is set, we shouldn't actually get here if
3580 there are further addresses, as the return above will be taken. However,
3581 writing RSET might have failed, or there may be other addresses whose hosts are
3582 specified in the transports, and therefore not visible at top level, in which
3583 case continue_more won't get set. */
3584
3585 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3586 if (sx.send_quit)
3587 {
3588 shutdown(sx.outblock.sock, SHUT_WR);
3589 if (fcntl(sx.inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3590 for (rc = 16; read(sx.inblock.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && rc > 0;)
3591 rc--; /* drain socket */
3592 }
3593 (void)close(sx.inblock.sock);
3594
3595 #ifndef DISABLE_EVENT
3596 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3597 #endif
3598
3599 continue_transport = NULL;
3600 continue_hostname = NULL;
3601 return yield;
3602 }
3603
3604
3605
3606
3607 /*************************************************
3608 * Closedown entry point *
3609 *************************************************/
3610
3611 /* This function is called when exim is passed an open smtp channel
3612 from another incarnation, but the message which it has been asked
3613 to deliver no longer exists. The channel is on stdin.
3614
3615 We might do fancy things like looking for another message to send down
3616 the channel, but if the one we sought has gone, it has probably been
3617 delivered by some other process that itself will seek further messages,
3618 so just close down our connection.
3619
3620 Argument: pointer to the transport instance block
3621 Returns: nothing
3622 */
3623
3624 void
3625 smtp_transport_closedown(transport_instance *tblock)
3626 {
3627 smtp_transport_options_block *ob =
3628 (smtp_transport_options_block *)tblock->options_block;
3629 smtp_inblock inblock;
3630 smtp_outblock outblock;
3631 uschar buffer[256];
3632 uschar inbuffer[4096];
3633 uschar outbuffer[16];
3634
3635 inblock.sock = fileno(stdin);
3636 inblock.buffer = inbuffer;
3637 inblock.buffersize = sizeof(inbuffer);
3638 inblock.ptr = inbuffer;
3639 inblock.ptrend = inbuffer;
3640
3641 outblock.sock = inblock.sock;
3642 outblock.buffersize = sizeof(outbuffer);
3643 outblock.buffer = outbuffer;
3644 outblock.ptr = outbuffer;
3645 outblock.cmd_count = 0;
3646 outblock.authenticating = FALSE;
3647
3648 (void)smtp_write_command(&outblock, SCMD_FLUSH, "QUIT\r\n");
3649 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3650 ob->command_timeout);
3651 (void)close(inblock.sock);
3652 }
3653
3654
3655
3656 /*************************************************
3657 * Prepare addresses for delivery *
3658 *************************************************/
3659
3660 /* This function is called to flush out error settings from previous delivery
3661 attempts to other hosts. It also records whether we got here via an MX record
3662 or not in the more_errno field of the address. We are interested only in
3663 addresses that are still marked DEFER - others may have got delivered to a
3664 previously considered IP address. Set their status to PENDING_DEFER to indicate
3665 which ones are relevant this time.
3666
3667 Arguments:
3668 addrlist the list of addresses
3669 host the host we are delivering to
3670
3671 Returns: the first address for this delivery
3672 */
3673
3674 static address_item *
3675 prepare_addresses(address_item *addrlist, host_item *host)
3676 {
3677 address_item *first_addr = NULL;
3678 address_item *addr;
3679 for (addr = addrlist; addr; addr = addr->next)
3680 if (addr->transport_return == DEFER)
3681 {
3682 if (!first_addr) first_addr = addr;
3683 addr->transport_return = PENDING_DEFER;
3684 addr->basic_errno = 0;
3685 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3686 addr->message = NULL;
3687 #ifdef SUPPORT_TLS
3688 addr->cipher = NULL;
3689 addr->ourcert = NULL;
3690 addr->peercert = NULL;
3691 addr->peerdn = NULL;
3692 addr->ocsp = OCSP_NOT_REQ;
3693 #endif
3694 #ifdef EXPERIMENTAL_DSN_INFO
3695 addr->smtp_greeting = NULL;
3696 addr->helo_response = NULL;
3697 #endif
3698 }
3699 return first_addr;
3700 }
3701
3702
3703
3704 /*************************************************
3705 * Main entry point *
3706 *************************************************/
3707
3708 /* See local README for interface details. As this is a remote transport, it is
3709 given a chain of addresses to be delivered in one connection, if possible. It
3710 always returns TRUE, indicating that each address has its own independent
3711 status set, except if there is a setting up problem, in which case it returns
3712 FALSE. */
3713
3714 BOOL
3715 smtp_transport_entry(
3716 transport_instance *tblock, /* data for this instantiation */
3717 address_item *addrlist) /* addresses we are working on */
3718 {
3719 int cutoff_retry;
3720 int defport;
3721 int hosts_defer = 0;
3722 int hosts_fail = 0;
3723 int hosts_looked_up = 0;
3724 int hosts_retry = 0;
3725 int hosts_serial = 0;
3726 int hosts_total = 0;
3727 int total_hosts_tried = 0;
3728 address_item *addr;
3729 BOOL expired = TRUE;
3730 uschar *expanded_hosts = NULL;
3731 uschar *pistring;
3732 uschar *tid = string_sprintf("%s transport", tblock->name);
3733 smtp_transport_options_block *ob =
3734 (smtp_transport_options_block *)(tblock->options_block);
3735 host_item *hostlist = addrlist->host_list;
3736 host_item *host;
3737
3738 DEBUG(D_transport)
3739 {
3740 debug_printf("%s transport entered\n", tblock->name);
3741 for (addr = addrlist; addr; addr = addr->next)
3742 debug_printf(" %s\n", addr->address);
3743 if (hostlist)
3744 {
3745 debug_printf("hostlist:\n");
3746 for (host = hostlist; host; host = host->next)
3747 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
3748 }
3749 if (continue_hostname)
3750 debug_printf("already connected to %s [%s] (on fd %d)\n",
3751 continue_hostname, continue_host_address,
3752 cutthrough.fd >= 0 ? cutthrough.fd : 0);
3753 }
3754
3755 /* Set the flag requesting that these hosts be added to the waiting
3756 database if the delivery fails temporarily or if we are running with
3757 queue_smtp or a 2-stage queue run. This gets unset for certain
3758 kinds of error, typically those that are specific to the message. */
3759
3760 update_waiting = TRUE;
3761
3762 /* If a host list is not defined for the addresses - they must all have the
3763 same one in order to be passed to a single transport - or if the transport has
3764 a host list with hosts_override set, use the host list supplied with the
3765 transport. It is an error for this not to exist. */
3766
3767 if (!hostlist || (ob->hosts_override && ob->hosts))
3768 {
3769 if (!ob->hosts)
3770 {
3771 addrlist->message = string_sprintf("%s transport called with no hosts set",
3772 tblock->name);
3773 addrlist->transport_return = PANIC;
3774 return FALSE; /* Only top address has status */
3775 }
3776
3777 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3778 ob->hosts);
3779
3780 /* If the transport's host list contains no '$' characters, and we are not
3781 randomizing, it is fixed and therefore a chain of hosts can be built once
3782 and for all, and remembered for subsequent use by other calls to this
3783 transport. If, on the other hand, the host list does contain '$', or we are
3784 randomizing its order, we have to rebuild it each time. In the fixed case,
3785 as the hosts string will never be used again, it doesn't matter that we
3786 replace all the : characters with zeros. */
3787
3788 if (!ob->hostlist)
3789 {
3790 uschar *s = ob->hosts;
3791
3792 if (Ustrchr(s, '$') != NULL)
3793 {
3794 if (!(expanded_hosts = expand_string(s)))
3795 {
3796 addrlist->message = string_sprintf("failed to expand list of