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Logging: fix duplicated transport target info under TFO
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11
12 /* Options specific to the smtp transport. This transport also supports LMTP
13 over TCP/IP. The options must be in alphabetic order (note that "_" comes
14 before the lower case letters). Some live in the transport_instance block so as
15 to be publicly visible; these are flagged with opt_public. */
16
17 optionlist smtp_transport_options[] = {
18 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
19 (void *)offsetof(transport_instance, expand_multi_domain) },
20 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
21 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
22
23 { "address_retry_include_sender", opt_bool,
24 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
25 { "allow_localhost", opt_bool,
26 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
27 #ifdef EXPERIMENTAL_ARC
28 { "arc_sign", opt_stringptr,
29 (void *)offsetof(smtp_transport_options_block, arc_sign) },
30 #endif
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 # ifdef SUPPORT_DANE
42 { "dane_require_tls_ciphers", opt_stringptr,
43 (void *)offsetof(smtp_transport_options_block, dane_require_tls_ciphers) },
44 # endif
45 { "data_timeout", opt_time,
46 (void *)offsetof(smtp_transport_options_block, data_timeout) },
47 { "delay_after_cutoff", opt_bool,
48 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
49 #ifndef DISABLE_DKIM
50 { "dkim_canon", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
52 { "dkim_domain", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
54 { "dkim_hash", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_hash) },
56 { "dkim_identity", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_identity) },
58 { "dkim_private_key", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
60 { "dkim_selector", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
62 { "dkim_sign_headers", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
64 { "dkim_strict", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
66 { "dkim_timestamps", opt_stringptr,
67 (void *)offsetof(smtp_transport_options_block, dkim.dkim_timestamps) },
68 #endif
69 { "dns_qualify_single", opt_bool,
70 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
71 { "dns_search_parents", opt_bool,
72 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
73 { "dnssec_request_domains", opt_stringptr,
74 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
75 { "dnssec_require_domains", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
77 { "dscp", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, dscp) },
79 { "fallback_hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
81 { "final_timeout", opt_time,
82 (void *)offsetof(smtp_transport_options_block, final_timeout) },
83 { "gethostbyname", opt_bool,
84 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
85 { "helo_data", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, helo_data) },
87 { "hosts", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts) },
89 { "hosts_avoid_esmtp", opt_stringptr,
90 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
91 { "hosts_avoid_pipelining", opt_stringptr,
92 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
93 #ifndef DISABLE_TLS
94 { "hosts_avoid_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
96 #endif
97 { "hosts_max_try", opt_int,
98 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
99 { "hosts_max_try_hardlimit", opt_int,
100 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
101 #ifndef DISABLE_TLS
102 { "hosts_nopass_tls", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
104 { "hosts_noproxy_tls", opt_stringptr,
105 (void *)offsetof(smtp_transport_options_block, hosts_noproxy_tls) },
106 #endif
107 { "hosts_override", opt_bool,
108 (void *)offsetof(smtp_transport_options_block, hosts_override) },
109 #ifdef EXPERIMENTAL_PIPE_CONNECT
110 { "hosts_pipe_connect", opt_stringptr,
111 (void *)offsetof(smtp_transport_options_block, hosts_pipe_connect) },
112 #endif
113 { "hosts_randomize", opt_bool,
114 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
115 #if !defined(DISABLE_TLS) && !defined(DISABLE_OCSP)
116 { "hosts_request_ocsp", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
118 #endif
119 { "hosts_require_auth", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
121 #ifndef DISABLE_TLS
122 # ifdef SUPPORT_DANE
123 { "hosts_require_dane", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
125 # endif
126 # ifndef DISABLE_OCSP
127 { "hosts_require_ocsp", opt_stringptr,
128 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
129 # endif
130 { "hosts_require_tls", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
132 #endif
133 { "hosts_try_auth", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
135 { "hosts_try_chunking", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
137 #ifdef SUPPORT_DANE
138 { "hosts_try_dane", opt_stringptr,
139 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
140 #endif
141 { "hosts_try_fastopen", opt_stringptr,
142 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
143 #ifndef DISABLE_PRDR
144 { "hosts_try_prdr", opt_stringptr,
145 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
146 #endif
147 #ifndef DISABLE_TLS
148 { "hosts_verify_avoid_tls", opt_stringptr,
149 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
150 #endif
151 { "interface", opt_stringptr,
152 (void *)offsetof(smtp_transport_options_block, interface) },
153 { "keepalive", opt_bool,
154 (void *)offsetof(smtp_transport_options_block, keepalive) },
155 { "lmtp_ignore_quota", opt_bool,
156 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
157 { "max_rcpt", opt_int | opt_public,
158 (void *)offsetof(transport_instance, max_addresses) },
159 { "multi_domain", opt_expand_bool | opt_public,
160 (void *)offsetof(transport_instance, multi_domain) },
161 { "port", opt_stringptr,
162 (void *)offsetof(smtp_transport_options_block, port) },
163 { "protocol", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, protocol) },
165 { "retry_include_ip_address", opt_expand_bool,
166 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
167 { "serialize_hosts", opt_stringptr,
168 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
169 { "size_addition", opt_int,
170 (void *)offsetof(smtp_transport_options_block, size_addition) },
171 #ifdef SUPPORT_SOCKS
172 { "socks_proxy", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, socks_proxy) },
174 #endif
175 #ifndef DISABLE_TLS
176 { "tls_certificate", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
178 { "tls_crl", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_crl) },
180 { "tls_dh_min_bits", opt_int,
181 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
182 { "tls_privatekey", opt_stringptr,
183 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
184 { "tls_require_ciphers", opt_stringptr,
185 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
186 # ifdef EXPERIMENTAL_TLS_RESUME
187 { "tls_resumption_hosts", opt_stringptr,
188 (void *)offsetof(smtp_transport_options_block, tls_resumption_hosts) },
189 # endif
190 { "tls_sni", opt_stringptr,
191 (void *)offsetof(smtp_transport_options_block, tls_sni) },
192 { "tls_tempfail_tryclear", opt_bool,
193 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
194 { "tls_try_verify_hosts", opt_stringptr,
195 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
196 { "tls_verify_cert_hostnames", opt_stringptr,
197 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
198 { "tls_verify_certificates", opt_stringptr,
199 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
200 { "tls_verify_hosts", opt_stringptr,
201 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) },
202 #endif
203 #ifdef SUPPORT_I18N
204 { "utf8_downconvert", opt_stringptr,
205 (void *)offsetof(smtp_transport_options_block, utf8_downconvert) },
206 #endif
207 };
208
209 /* Size of the options list. An extern variable has to be used so that its
210 address can appear in the tables drtables.c. */
211
212 int smtp_transport_options_count = nelem(smtp_transport_options);
213
214
215 #ifdef MACRO_PREDEF
216
217 /* Dummy values */
218 smtp_transport_options_block smtp_transport_option_defaults = {0};
219 void smtp_transport_init(transport_instance *tblock) {}
220 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
221 void smtp_transport_closedown(transport_instance *tblock) {}
222
223 #else /*!MACRO_PREDEF*/
224
225
226 /* Default private options block for the smtp transport. */
227
228 smtp_transport_options_block smtp_transport_option_defaults = {
229 .hosts = NULL,
230 .fallback_hosts = NULL,
231 .hostlist = NULL,
232 .fallback_hostlist = NULL,
233 .helo_data = US"$primary_hostname",
234 .interface = NULL,
235 .port = NULL,
236 .protocol = US"smtp",
237 .dscp = NULL,
238 .serialize_hosts = NULL,
239 .hosts_try_auth = NULL,
240 .hosts_require_auth = NULL,
241 .hosts_try_chunking = US"*",
242 #ifdef SUPPORT_DANE
243 .hosts_try_dane = US"*",
244 .hosts_require_dane = NULL,
245 .dane_require_tls_ciphers = NULL,
246 #endif
247 .hosts_try_fastopen = NULL,
248 #ifndef DISABLE_PRDR
249 .hosts_try_prdr = US"*",
250 #endif
251 #ifndef DISABLE_OCSP
252 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
253 .hosts_require_ocsp = NULL,
254 #endif
255 .hosts_require_tls = NULL,
256 .hosts_avoid_tls = NULL,
257 .hosts_verify_avoid_tls = NULL,
258 .hosts_avoid_pipelining = NULL,
259 #ifdef EXPERIMENTAL_PIPE_CONNECT
260 .hosts_pipe_connect = NULL,
261 #endif
262 .hosts_avoid_esmtp = NULL,
263 #ifndef DISABLE_TLS
264 .hosts_nopass_tls = NULL,
265 .hosts_noproxy_tls = NULL,
266 #endif
267 .command_timeout = 5*60,
268 .connect_timeout = 5*60,
269 .data_timeout = 5*60,
270 .final_timeout = 10*60,
271 .size_addition = 1024,
272 .hosts_max_try = 5,
273 .hosts_max_try_hardlimit = 50,
274 .address_retry_include_sender = TRUE,
275 .allow_localhost = FALSE,
276 .authenticated_sender_force = FALSE,
277 .gethostbyname = FALSE,
278 .dns_qualify_single = TRUE,
279 .dns_search_parents = FALSE,
280 .dnssec = { .request=NULL, .require=NULL },
281 .delay_after_cutoff = TRUE,
282 .hosts_override = FALSE,
283 .hosts_randomize = FALSE,
284 .keepalive = TRUE,
285 .lmtp_ignore_quota = FALSE,
286 .expand_retry_include_ip_address = NULL,
287 .retry_include_ip_address = TRUE,
288 #ifdef SUPPORT_SOCKS
289 .socks_proxy = NULL,
290 #endif
291 #ifndef DISABLE_TLS
292 .tls_certificate = NULL,
293 .tls_crl = NULL,
294 .tls_privatekey = NULL,
295 .tls_require_ciphers = NULL,
296 .tls_sni = NULL,
297 .tls_verify_certificates = US"system",
298 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
299 .tls_tempfail_tryclear = TRUE,
300 # ifdef EXPERIMENTAL_TLS_RESUME
301 .tls_resumption_hosts = NULL,
302 # endif
303 .tls_verify_hosts = NULL,
304 .tls_try_verify_hosts = US"*",
305 .tls_verify_cert_hostnames = US"*",
306 #endif
307 #ifdef SUPPORT_I18N
308 .utf8_downconvert = NULL,
309 #endif
310 #ifndef DISABLE_DKIM
311 .dkim =
312 {.dkim_domain = NULL,
313 .dkim_identity = NULL,
314 .dkim_private_key = NULL,
315 .dkim_selector = NULL,
316 .dkim_canon = NULL,
317 .dkim_sign_headers = NULL,
318 .dkim_strict = NULL,
319 .dkim_hash = US"sha256",
320 .dkim_timestamps = NULL,
321 .dot_stuffed = FALSE,
322 .force_bodyhash = FALSE,
323 # ifdef EXPERIMENTAL_ARC
324 .arc_signspec = NULL,
325 # endif
326 },
327 # ifdef EXPERIMENTAL_ARC
328 .arc_sign = NULL,
329 # endif
330 #endif
331 };
332
333 /* some DSN flags for use later */
334
335 static int rf_list[] = {rf_notify_never, rf_notify_success,
336 rf_notify_failure, rf_notify_delay };
337
338 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
339
340
341
342 /* Local statics */
343
344 static uschar *smtp_command; /* Points to last cmd for error messages */
345 static uschar *mail_command; /* Points to MAIL cmd for error messages */
346 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
347 static BOOL update_waiting; /* TRUE to update the "wait" database */
348
349 /*XXX move to smtp_context */
350 static BOOL pipelining_active; /* current transaction is in pipe mode */
351
352
353 static unsigned ehlo_response(uschar * buf, unsigned checks);
354
355
356 /*************************************************
357 * Setup entry point *
358 *************************************************/
359
360 /* This function is called when the transport is about to be used,
361 but before running it in a sub-process. It is used for two things:
362
363 (1) To set the fallback host list in addresses, when delivering.
364 (2) To pass back the interface, port, protocol, and other options, for use
365 during callout verification.
366
367 Arguments:
368 tblock pointer to the transport instance block
369 addrlist list of addresses about to be transported
370 tf if not NULL, pointer to block in which to return options
371 uid the uid that will be set (not used)
372 gid the gid that will be set (not used)
373 errmsg place for error message (not used)
374
375 Returns: OK always (FAIL, DEFER not used)
376 */
377
378 static int
379 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
380 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
381 {
382 smtp_transport_options_block *ob = SOB tblock->options_block;
383
384 errmsg = errmsg; /* Keep picky compilers happy */
385 uid = uid;
386 gid = gid;
387
388 /* Pass back options if required. This interface is getting very messy. */
389
390 if (tf)
391 {
392 tf->interface = ob->interface;
393 tf->port = ob->port;
394 tf->protocol = ob->protocol;
395 tf->hosts = ob->hosts;
396 tf->hosts_override = ob->hosts_override;
397 tf->hosts_randomize = ob->hosts_randomize;
398 tf->gethostbyname = ob->gethostbyname;
399 tf->qualify_single = ob->dns_qualify_single;
400 tf->search_parents = ob->dns_search_parents;
401 tf->helo_data = ob->helo_data;
402 }
403
404 /* Set the fallback host list for all the addresses that don't have fallback
405 host lists, provided that the local host wasn't present in the original host
406 list. */
407
408 if (!testflag(addrlist, af_local_host_removed))
409 for (; addrlist; addrlist = addrlist->next)
410 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
411
412 return OK;
413 }
414
415
416
417 /*************************************************
418 * Initialization entry point *
419 *************************************************/
420
421 /* Called for each instance, after its options have been read, to
422 enable consistency checks to be done, or anything else that needs
423 to be set up.
424
425 Argument: pointer to the transport instance block
426 Returns: nothing
427 */
428
429 void
430 smtp_transport_init(transport_instance *tblock)
431 {
432 smtp_transport_options_block *ob = SOB tblock->options_block;
433
434 /* Retry_use_local_part defaults FALSE if unset */
435
436 if (tblock->retry_use_local_part == TRUE_UNSET)
437 tblock->retry_use_local_part = FALSE;
438
439 /* Set the default port according to the protocol */
440
441 if (!ob->port)
442 ob->port = strcmpic(ob->protocol, US"lmtp") == 0
443 ? US"lmtp"
444 : strcmpic(ob->protocol, US"smtps") == 0
445 ? US"smtps" : US"smtp";
446
447 /* Set up the setup entry point, to be called before subprocesses for this
448 transport. */
449
450 tblock->setup = smtp_transport_setup;
451
452 /* Complain if any of the timeouts are zero. */
453
454 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
455 ob->final_timeout <= 0)
456 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
457 "command, data, or final timeout value is zero for %s transport",
458 tblock->name);
459
460 /* If hosts_override is set and there are local hosts, set the global
461 flag that stops verify from showing router hosts. */
462
463 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
464
465 /* If there are any fallback hosts listed, build a chain of host items
466 for them, but do not do any lookups at this time. */
467
468 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
469 }
470
471
472
473
474
475 /*************************************************
476 * Set delivery info into all active addresses *
477 *************************************************/
478
479 /* Only addresses whose status is >= PENDING are relevant. A lesser
480 status means that an address is not currently being processed.
481
482 Arguments:
483 addrlist points to a chain of addresses
484 errno_value to put in each address's errno field
485 msg to put in each address's message field
486 rc to put in each address's transport_return field
487 pass_message if TRUE, set the "pass message" flag in the address
488 host if set, mark addrs as having used this host
489 smtp_greeting from peer
490 helo_response from peer
491
492 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
493 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
494 this particular type of timeout.
495
496 Returns: nothing
497 */
498
499 static void
500 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
501 BOOL pass_message, host_item * host
502 #ifdef EXPERIMENTAL_DSN_INFO
503 , const uschar * smtp_greeting, const uschar * helo_response
504 #endif
505 )
506 {
507 int orvalue = 0;
508 if (errno_value == ERRNO_CONNECTTIMEOUT)
509 {
510 errno_value = ETIMEDOUT;
511 orvalue = RTEF_CTOUT;
512 }
513 for (address_item * addr = addrlist; addr; addr = addr->next)
514 if (addr->transport_return >= PENDING)
515 {
516 addr->basic_errno = errno_value;
517 addr->more_errno |= orvalue;
518 if (msg)
519 {
520 addr->message = msg;
521 if (pass_message) setflag(addr, af_pass_message);
522 }
523 addr->transport_return = rc;
524 if (host)
525 {
526 addr->host_used = host;
527 #ifdef EXPERIMENTAL_DSN_INFO
528 if (smtp_greeting)
529 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
530 addr->smtp_greeting = smtp_greeting;
531
532 if (helo_response)
533 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
534 addr->helo_response = helo_response;
535 #endif
536 }
537 }
538 }
539
540 static void
541 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
542 BOOL pass_message)
543 {
544 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
545 #ifdef EXPERIMENTAL_DSN_INFO
546 , NULL, NULL
547 #endif
548 );
549 }
550
551
552 /*************************************************
553 * Check an SMTP response *
554 *************************************************/
555
556 /* This function is given an errno code and the SMTP response buffer
557 to analyse, together with the host identification for generating messages. It
558 sets an appropriate message and puts the first digit of the response code into
559 the yield variable. If no response was actually read, a suitable digit is
560 chosen.
561
562 Arguments:
563 host the current host, to get its name for messages
564 errno_value pointer to the errno value
565 more_errno from the top address for use with ERRNO_FILTER_FAIL
566 buffer the SMTP response buffer
567 yield where to put a one-digit SMTP response code
568 message where to put an error message
569 pass_message set TRUE if message is an SMTP response
570
571 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
572 */
573
574 static BOOL
575 check_response(host_item *host, int *errno_value, int more_errno,
576 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
577 {
578 uschar * pl = pipelining_active ? US"pipelined " : US"";
579 const uschar * s;
580
581 *yield = '4'; /* Default setting is to give a temporary error */
582
583 switch(*errno_value)
584 {
585 case ETIMEDOUT: /* Handle response timeout */
586 *message = US string_sprintf("SMTP timeout after %s%s",
587 pl, smtp_command);
588 if (transport_count > 0)
589 *message = US string_sprintf("%s (%d bytes written)", *message,
590 transport_count);
591 return FALSE;
592
593 case ECONNREFUSED: /* First-read error on a TFO conn */
594 if (verify_mode) *message = US strerror(*errno_value);
595 return FALSE; /* nonverify, do not set message */
596
597 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
598 s = string_printing(buffer);
599 while (isspace(*s)) s++;
600 *message = *s == 0
601 ? string_sprintf("Malformed SMTP reply (an empty line) "
602 "in response to %s%s", pl, smtp_command)
603 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
604 pl, smtp_command, s);
605 return FALSE;
606
607 case ERRNO_TLSFAILURE: /* Handle bad first read; can happen with
608 GnuTLS and TLS1.3 */
609 *message = US"bad first read from TLS conn";
610 return TRUE;
611
612 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
613 can't send QUIT as we mustn't end the DATA. */
614 *message = string_sprintf("transport filter process failed (%d)%s",
615 more_errno,
616 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
617 return FALSE;
618
619 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
620 can't send QUIT as we mustn't end the DATA. */
621 *message =
622 string_sprintf("failed to expand headers_add or headers_remove: %s",
623 expand_string_message);
624 return FALSE;
625
626 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
627 *message = string_sprintf("failed to write a data block");
628 return FALSE;
629
630 #ifdef SUPPORT_I18N
631 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
632 *message = US"utf8 support required but not offered for forwarding";
633 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
634 return TRUE;
635 #endif
636 }
637
638 /* Handle error responses from the remote mailer. */
639
640 if (buffer[0] != 0)
641 {
642 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
643 "%s", pl, smtp_command, s = string_printing(buffer));
644 *pass_message = TRUE;
645 *yield = buffer[0];
646 return TRUE;
647 }
648
649 /* No data was read. If there is no errno, this must be the EOF (i.e.
650 connection closed) case, which causes deferral. An explicit connection reset
651 error has the same effect. Otherwise, put the host's identity in the message,
652 leaving the errno value to be interpreted as well. In all cases, we have to
653 assume the connection is now dead. */
654
655 if (*errno_value == 0 || *errno_value == ECONNRESET)
656 {
657 *errno_value = ERRNO_SMTPCLOSED;
658 *message = US string_sprintf("Remote host closed connection "
659 "in response to %s%s", pl, smtp_command);
660 }
661 else
662 *message = US string_sprintf("%s [%s]", host->name, host->address);
663
664 return FALSE;
665 }
666
667
668
669 /*************************************************
670 * Write error message to logs *
671 *************************************************/
672
673 /* This writes to the main log and to the message log.
674
675 Arguments:
676 host the current host
677 detail the current message (addr_item->message)
678 basic_errno the errno (addr_item->basic_errno)
679
680 Returns: nothing
681 */
682
683 static void
684 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
685 {
686 gstring * message = LOGGING(outgoing_port)
687 ? string_fmt_append(NULL, "H=%s [%s]:%d", host->name, host->address,
688 host->port == PORT_NONE ? 25 : host->port)
689 : string_fmt_append(NULL, "H=%s [%s]", host->name, host->address);
690
691 if (suffix)
692 {
693 message = string_fmt_append(message, ": %s", suffix);
694 if (basic_errno > 0)
695 message = string_fmt_append(message, ": %s", strerror(basic_errno));
696 }
697 else
698 message = string_fmt_append(message, " %s", exim_errstr(basic_errno));
699
700 log_write(0, LOG_MAIN, "%s", string_from_gstring(message));
701 deliver_msglog("%s %s\n", tod_stamp(tod_log), message->s);
702 }
703
704 static void
705 msglog_line(host_item * host, uschar * message)
706 {
707 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
708 host->name, host->address, message);
709 }
710
711
712
713 #ifndef DISABLE_EVENT
714 /*************************************************
715 * Post-defer action *
716 *************************************************/
717
718 /* This expands an arbitrary per-transport string.
719 It might, for example, be used to write to the database log.
720
721 Arguments:
722 addr the address item containing error information
723 host the current host
724
725 Returns: nothing
726 */
727
728 static void
729 deferred_event_raise(address_item *addr, host_item *host)
730 {
731 uschar * action = addr->transport->event_action;
732 const uschar * save_domain;
733 uschar * save_local;
734
735 if (!action)
736 return;
737
738 save_domain = deliver_domain;
739 save_local = deliver_localpart;
740
741 /*XXX would ip & port already be set up? */
742 deliver_host_address = string_copy(host->address);
743 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
744 event_defer_errno = addr->basic_errno;
745
746 router_name = addr->router->name;
747 transport_name = addr->transport->name;
748 deliver_domain = addr->domain;
749 deliver_localpart = addr->local_part;
750
751 (void) event_raise(action, US"msg:host:defer",
752 addr->message
753 ? addr->basic_errno > 0
754 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
755 : string_copy(addr->message)
756 : addr->basic_errno > 0
757 ? string_copy(US strerror(addr->basic_errno))
758 : NULL);
759
760 deliver_localpart = save_local;
761 deliver_domain = save_domain;
762 router_name = transport_name = NULL;
763 }
764 #endif
765
766 /*************************************************
767 * Reap SMTP specific responses *
768 *************************************************/
769 static int
770 smtp_discard_responses(smtp_context * sx, smtp_transport_options_block * ob,
771 int count)
772 {
773 uschar flushbuffer[4096];
774
775 while (count-- > 0)
776 {
777 if (!smtp_read_response(sx, flushbuffer, sizeof(flushbuffer),
778 '2', ob->command_timeout)
779 && (errno != 0 || flushbuffer[0] == 0))
780 break;
781 }
782 return count;
783 }
784
785
786 /* Return boolean success */
787
788 static BOOL
789 smtp_reap_banner(smtp_context * sx)
790 {
791 BOOL good_response = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
792 '2', (SOB sx->conn_args.ob)->command_timeout);
793 #ifdef EXPERIMENTAL_DSN_INFO
794 sx->smtp_greeting = string_copy(sx->buffer);
795 #endif
796 return good_response;
797 }
798
799 static BOOL
800 smtp_reap_ehlo(smtp_context * sx)
801 {
802 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
803 (SOB sx->conn_args.ob)->command_timeout))
804 {
805 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
806 {
807 #ifdef EXPERIMENTAL_DSN_INFO
808 sx->helo_response = string_copy(sx->buffer);
809 #endif
810 return FALSE;
811 }
812 sx->esmtp = FALSE;
813 }
814 #ifdef EXPERIMENTAL_DSN_INFO
815 sx->helo_response = string_copy(sx->buffer);
816 #endif
817 return TRUE;
818 }
819
820
821
822 #ifdef EXPERIMENTAL_PIPE_CONNECT
823 static uschar *
824 ehlo_cache_key(const smtp_context * sx)
825 {
826 host_item * host = sx->conn_args.host;
827 return Ustrchr(host->address, ':')
828 ? string_sprintf("[%s]:%d.EHLO", host->address,
829 host->port == PORT_NONE ? sx->port : host->port)
830 : string_sprintf("%s:%d.EHLO", host->address,
831 host->port == PORT_NONE ? sx->port : host->port);
832 }
833
834 static void
835 write_ehlo_cache_entry(const smtp_context * sx)
836 {
837 open_db dbblock, * dbm_file;
838
839 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
840 {
841 uschar * ehlo_resp_key = ehlo_cache_key(sx);
842 dbdata_ehlo_resp er = { .data = sx->ehlo_resp };
843
844 HDEBUG(D_transport) debug_printf("writing clr %04x/%04x cry %04x/%04x\n",
845 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
846 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths);
847
848 dbfn_write(dbm_file, ehlo_resp_key, &er, (int)sizeof(er));
849 dbfn_close(dbm_file);
850 }
851 }
852
853 static void
854 invalidate_ehlo_cache_entry(smtp_context * sx)
855 {
856 open_db dbblock, * dbm_file;
857
858 if ( sx->early_pipe_active
859 && (dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
860 {
861 uschar * ehlo_resp_key = ehlo_cache_key(sx);
862 dbfn_delete(dbm_file, ehlo_resp_key);
863 dbfn_close(dbm_file);
864 }
865 }
866
867 static BOOL
868 read_ehlo_cache_entry(smtp_context * sx)
869 {
870 open_db dbblock;
871 open_db * dbm_file;
872
873 if (!(dbm_file = dbfn_open(US"misc", O_RDONLY, &dbblock, FALSE, TRUE)))
874 { DEBUG(D_transport) debug_printf("ehlo-cache: no misc DB\n"); }
875 else
876 {
877 uschar * ehlo_resp_key = ehlo_cache_key(sx);
878 dbdata_ehlo_resp * er;
879
880 if (!(er = dbfn_read(dbm_file, ehlo_resp_key)))
881 { DEBUG(D_transport) debug_printf("no ehlo-resp record\n"); }
882 else if (time(NULL) - er->time_stamp > retry_data_expire)
883 {
884 DEBUG(D_transport) debug_printf("ehlo-resp record too old\n");
885 dbfn_close(dbm_file);
886 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
887 dbfn_delete(dbm_file, ehlo_resp_key);
888 }
889 else
890 {
891 sx->ehlo_resp = er->data;
892 dbfn_close(dbm_file);
893 DEBUG(D_transport) debug_printf(
894 "EHLO response bits from cache: cleartext 0x%04x crypted 0x%04x\n",
895 er->data.cleartext_features, er->data.crypted_features);
896 return TRUE;
897 }
898 dbfn_close(dbm_file);
899 }
900 return FALSE;
901 }
902
903
904
905 /* Return an auths bitmap for the set of AUTH methods offered by the server
906 which match our authenticators. */
907
908 static unsigned short
909 study_ehlo_auths(smtp_context * sx)
910 {
911 uschar * names;
912 auth_instance * au;
913 uschar authnum;
914 unsigned short authbits = 0;
915
916 if (!sx->esmtp) return 0;
917 if (!regex_AUTH) regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
918 if (!regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)) return 0;
919 expand_nmax = -1; /* reset */
920 names = string_copyn(expand_nstring[1], expand_nlength[1]);
921
922 for (au = auths, authnum = 0; au; au = au->next, authnum++) if (au->client)
923 {
924 const uschar * list = names;
925 int sep = ' ';
926 uschar name[32];
927
928 while (string_nextinlist(&list, &sep, name, sizeof(name)))
929 if (strcmpic(au->public_name, name) == 0)
930 { authbits |= BIT(authnum); break; }
931 }
932
933 DEBUG(D_transport)
934 debug_printf("server offers %s AUTH, methods '%s', bitmap 0x%04x\n",
935 tls_out.active.sock >= 0 ? "crypted" : "plaintext", names, authbits);
936
937 if (tls_out.active.sock >= 0)
938 sx->ehlo_resp.crypted_auths = authbits;
939 else
940 sx->ehlo_resp.cleartext_auths = authbits;
941 return authbits;
942 }
943
944
945
946
947 /* Wait for and check responses for early-pipelining.
948
949 Called from the lower-level smtp_read_response() function
950 used for general code that assume synchronisation, if context
951 flags indicate outstanding early-pipelining commands. Also
952 called fom sync_responses() which handles pipelined commands.
953
954 Arguments:
955 sx smtp connection context
956 countp number of outstanding responses, adjusted on return
957
958 Return:
959 OK all well
960 DEFER error on first read of TLS'd conn
961 FAIL SMTP error in response
962 */
963 int
964 smtp_reap_early_pipe(smtp_context * sx, int * countp)
965 {
966 BOOL pending_BANNER = sx->pending_BANNER;
967 BOOL pending_EHLO = sx->pending_EHLO;
968 int rc = FAIL;
969
970 sx->pending_BANNER = FALSE; /* clear early to avoid recursion */
971 sx->pending_EHLO = FALSE;
972
973 if (pending_BANNER)
974 {
975 DEBUG(D_transport) debug_printf("%s expect banner\n", __FUNCTION__);
976 (*countp)--;
977 if (!smtp_reap_banner(sx))
978 {
979 DEBUG(D_transport) debug_printf("bad banner\n");
980 if (tls_out.active.sock >= 0) rc = DEFER;
981 goto fail;
982 }
983 }
984
985 if (pending_EHLO)
986 {
987 unsigned peer_offered;
988 unsigned short authbits = 0, * ap;
989
990 DEBUG(D_transport) debug_printf("%s expect ehlo\n", __FUNCTION__);
991 (*countp)--;
992 if (!smtp_reap_ehlo(sx))
993 {
994 DEBUG(D_transport) debug_printf("bad response for EHLO\n");
995 if (tls_out.active.sock >= 0) rc = DEFER;
996 goto fail;
997 }
998
999 /* Compare the actual EHLO response to the cached value we assumed;
1000 on difference, dump or rewrite the cache and arrange for a retry. */
1001
1002 ap = tls_out.active.sock < 0
1003 ? &sx->ehlo_resp.cleartext_auths : &sx->ehlo_resp.crypted_auths;
1004
1005 peer_offered = ehlo_response(sx->buffer,
1006 (tls_out.active.sock < 0 ? OPTION_TLS : 0)
1007 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
1008 | OPTION_UTF8 | OPTION_EARLY_PIPE
1009 );
1010 if ( peer_offered != sx->peer_offered
1011 || (authbits = study_ehlo_auths(sx)) != *ap)
1012 {
1013 HDEBUG(D_transport)
1014 debug_printf("EHLO %s extensions changed, 0x%04x/0x%04x -> 0x%04x/0x%04x\n",
1015 tls_out.active.sock < 0 ? "cleartext" : "crypted",
1016 sx->peer_offered, *ap, peer_offered, authbits);
1017 *(tls_out.active.sock < 0
1018 ? &sx->ehlo_resp.cleartext_features : &sx->ehlo_resp.crypted_features) = peer_offered;
1019 *ap = authbits;
1020 if (peer_offered & OPTION_EARLY_PIPE)
1021 write_ehlo_cache_entry(sx);
1022 else
1023 invalidate_ehlo_cache_entry(sx);
1024
1025 return OK; /* just carry on */
1026 }
1027 }
1028 return OK;
1029
1030 fail:
1031 invalidate_ehlo_cache_entry(sx);
1032 (void) smtp_discard_responses(sx, sx->conn_args.ob, *countp);
1033 return rc;
1034 }
1035 #endif
1036
1037
1038 /*************************************************
1039 * Synchronize SMTP responses *
1040 *************************************************/
1041
1042 /* This function is called from smtp_deliver() to receive SMTP responses from
1043 the server, and match them up with the commands to which they relate. When
1044 PIPELINING is not in use, this function is called after every command, and is
1045 therefore somewhat over-engineered, but it is simpler to use a single scheme
1046 that works both with and without PIPELINING instead of having two separate sets
1047 of code.
1048
1049 The set of commands that are buffered up with pipelining may start with MAIL
1050 and may end with DATA; in between are RCPT commands that correspond to the
1051 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
1052 etc.) are never buffered.
1053
1054 Errors after MAIL or DATA abort the whole process leaving the response in the
1055 buffer. After MAIL, pending responses are flushed, and the original command is
1056 re-instated in big_buffer for error messages. For RCPT commands, the remote is
1057 permitted to reject some recipient addresses while accepting others. However
1058 certain errors clearly abort the whole process. Set the value in
1059 transport_return to PENDING_OK if the address is accepted. If there is a
1060 subsequent general error, it will get reset accordingly. If not, it will get
1061 converted to OK at the end.
1062
1063 Arguments:
1064 sx smtp connection context
1065 count the number of responses to read
1066 pending_DATA 0 if last command sent was not DATA
1067 +1 if previously had a good recipient
1068 -1 if not previously had a good recipient
1069
1070 Returns: 3 if at least one address had 2xx and one had 5xx
1071 2 if at least one address had 5xx but none had 2xx
1072 1 if at least one host had a 2xx response, but none had 5xx
1073 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
1074 -1 timeout while reading RCPT response
1075 -2 I/O or other non-response error for RCPT
1076 -3 DATA or MAIL failed - errno and buffer set
1077 -4 banner or EHLO failed (early-pipelining)
1078 -5 banner or EHLO failed (early-pipelining, TLS)
1079 */
1080
1081 static int
1082 sync_responses(smtp_context * sx, int count, int pending_DATA)
1083 {
1084 address_item * addr = sx->sync_addr;
1085 smtp_transport_options_block * ob = sx->conn_args.ob;
1086 int yield = 0;
1087
1088 #ifdef EXPERIMENTAL_PIPE_CONNECT
1089 int rc;
1090 if ((rc = smtp_reap_early_pipe(sx, &count)) != OK)
1091 return rc == FAIL ? -4 : -5;
1092 #endif
1093
1094 /* Handle the response for a MAIL command. On error, reinstate the original
1095 command in big_buffer for error message use, and flush any further pending
1096 responses before returning, except after I/O errors and timeouts. */
1097
1098 if (sx->pending_MAIL)
1099 {
1100 DEBUG(D_transport) debug_printf("%s expect mail\n", __FUNCTION__);
1101 count--;
1102 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1103 '2', ob->command_timeout))
1104 {
1105 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
1106 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
1107 if (errno == ERRNO_TLSFAILURE)
1108 return -5;
1109 if (errno == 0 && sx->buffer[0] != 0)
1110 {
1111 int save_errno = 0;
1112 if (sx->buffer[0] == '4')
1113 {
1114 save_errno = ERRNO_MAIL4XX;
1115 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1116 }
1117 count = smtp_discard_responses(sx, ob, count);
1118 errno = save_errno;
1119 }
1120
1121 if (pending_DATA) count--; /* Number of RCPT responses to come */
1122 while (count-- > 0) /* Mark any pending addrs with the host used */
1123 {
1124 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
1125 addr->host_used = sx->conn_args.host;
1126 addr = addr->next;
1127 }
1128 return -3;
1129 }
1130 }
1131
1132 if (pending_DATA) count--; /* Number of RCPT responses to come */
1133
1134 /* Read and handle the required number of RCPT responses, matching each one up
1135 with an address by scanning for the next address whose status is PENDING_DEFER.
1136 */
1137
1138 while (count-- > 0)
1139 {
1140 while (addr->transport_return != PENDING_DEFER)
1141 if (!(addr = addr->next))
1142 return -2;
1143
1144 /* The address was accepted */
1145 addr->host_used = sx->conn_args.host;
1146
1147 DEBUG(D_transport) debug_printf("%s expect rcpt\n", __FUNCTION__);
1148 if (smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1149 '2', ob->command_timeout))
1150 {
1151 yield |= 1;
1152 addr->transport_return = PENDING_OK;
1153
1154 /* If af_dr_retry_exists is set, there was a routing delay on this address;
1155 ensure that any address-specific retry record is expunged. We do this both
1156 for the basic key and for the version that also includes the sender. */
1157
1158 if (testflag(addr, af_dr_retry_exists))
1159 {
1160 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
1161 sender_address);
1162 retry_add_item(addr, altkey, rf_delete);
1163 retry_add_item(addr, addr->address_retry_key, rf_delete);
1164 }
1165 }
1166
1167 /* Error on first TLS read */
1168
1169 else if (errno == ERRNO_TLSFAILURE)
1170 return -5;
1171
1172 /* Timeout while reading the response */
1173
1174 else if (errno == ETIMEDOUT)
1175 {
1176 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
1177 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1178 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
1179 retry_add_item(addr, addr->address_retry_key, 0);
1180 update_waiting = FALSE;
1181 return -1;
1182 }
1183
1184 /* Handle other errors in obtaining an SMTP response by returning -1. This
1185 will cause all the addresses to be deferred. Restore the SMTP command in
1186 big_buffer for which we are checking the response, so the error message
1187 makes sense. */
1188
1189 else if (errno != 0 || sx->buffer[0] == 0)
1190 {
1191 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
1192 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1193 return -2;
1194 }
1195
1196 /* Handle SMTP permanent and temporary response codes. */
1197
1198 else
1199 {
1200 addr->message =
1201 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
1202 "%s", transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes),
1203 string_printing(sx->buffer));
1204 setflag(addr, af_pass_message);
1205 if (!sx->verify)
1206 msglog_line(sx->conn_args.host, addr->message);
1207
1208 /* The response was 5xx */
1209
1210 if (sx->buffer[0] == '5')
1211 {
1212 addr->transport_return = FAIL;
1213 yield |= 2;
1214 }
1215
1216 /* The response was 4xx */
1217
1218 else
1219 {
1220 addr->transport_return = DEFER;
1221 addr->basic_errno = ERRNO_RCPT4XX;
1222 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1223
1224 if (!sx->verify)
1225 {
1226 #ifndef DISABLE_EVENT
1227 event_defer_errno = addr->more_errno;
1228 msg_event_raise(US"msg:rcpt:host:defer", addr);
1229 #endif
1230
1231 /* Log temporary errors if there are more hosts to be tried.
1232 If not, log this last one in the == line. */
1233
1234 if (sx->conn_args.host->next)
1235 if (LOGGING(outgoing_port))
1236 log_write(0, LOG_MAIN, "H=%s [%s]:%d %s", sx->conn_args.host->name,
1237 sx->conn_args.host->address,
1238 sx->port == PORT_NONE ? 25 : sx->port, addr->message);
1239 else
1240 log_write(0, LOG_MAIN, "H=%s [%s]: %s", sx->conn_args.host->name,
1241 sx->conn_args.host->address, addr->message);
1242
1243 #ifndef DISABLE_EVENT
1244 else
1245 msg_event_raise(US"msg:rcpt:defer", addr);
1246 #endif
1247
1248 /* Do not put this message on the list of those waiting for specific
1249 hosts, as otherwise it is likely to be tried too often. */
1250
1251 update_waiting = FALSE;
1252
1253 /* Add a retry item for the address so that it doesn't get tried again
1254 too soon. If address_retry_include_sender is true, add the sender address
1255 to the retry key. */
1256
1257 retry_add_item(addr,
1258 ob->address_retry_include_sender
1259 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
1260 : addr->address_retry_key,
1261 0);
1262 }
1263 }
1264 }
1265 } /* Loop for next RCPT response */
1266
1267 /* Update where to start at for the next block of responses, unless we
1268 have already handled all the addresses. */
1269
1270 if (addr) sx->sync_addr = addr->next;
1271
1272 /* Handle a response to DATA. If we have not had any good recipients, either
1273 previously or in this block, the response is ignored. */
1274
1275 if (pending_DATA != 0)
1276 {
1277 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1278 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1279 '3', ob->command_timeout))
1280 {
1281 int code;
1282 uschar *msg;
1283 BOOL pass_message;
1284
1285 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1286 return -5;
1287
1288 if (pending_DATA > 0 || (yield & 1) != 0)
1289 {
1290 if (errno == 0 && sx->buffer[0] == '4')
1291 {
1292 errno = ERRNO_DATA4XX;
1293 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1294 }
1295 return -3;
1296 }
1297 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1298 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1299 "is in use and there were no good recipients\n", msg);
1300 }
1301 }
1302
1303 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1304 present) received 3xx. If any RCPTs were handled and yielded anything other
1305 than 4xx, yield will be set non-zero. */
1306
1307 return yield;
1308 }
1309
1310
1311
1312
1313
1314 /* Try an authenticator's client entry */
1315
1316 static int
1317 try_authenticator(smtp_context * sx, auth_instance * au)
1318 {
1319 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1320 host_item * host = sx->conn_args.host; /* host to deliver to */
1321 int rc;
1322
1323 sx->outblock.authenticating = TRUE;
1324 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1325 sx->buffer, sizeof(sx->buffer));
1326 sx->outblock.authenticating = FALSE;
1327 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n", au->name, rc);
1328
1329 /* A temporary authentication failure must hold up delivery to
1330 this host. After a permanent authentication failure, we carry on
1331 to try other authentication methods. If all fail hard, try to
1332 deliver the message unauthenticated unless require_auth was set. */
1333
1334 switch(rc)
1335 {
1336 case OK:
1337 f.smtp_authenticated = TRUE; /* stops the outer loop */
1338 client_authenticator = au->name;
1339 if (au->set_client_id)
1340 client_authenticated_id = expand_string(au->set_client_id);
1341 break;
1342
1343 /* Failure after writing a command */
1344
1345 case FAIL_SEND:
1346 return FAIL_SEND;
1347
1348 /* Failure after reading a response */
1349
1350 case FAIL:
1351 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1352 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1353 au->name, host->name, host->address, sx->buffer);
1354 break;
1355
1356 /* Failure by some other means. In effect, the authenticator
1357 decided it wasn't prepared to handle this case. Typically this
1358 is the result of "fail" in an expansion string. Do we need to
1359 log anything here? Feb 2006: a message is now put in the buffer
1360 if logging is required. */
1361
1362 case CANCELLED:
1363 if (*sx->buffer != 0)
1364 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1365 "authentication H=%s [%s] %s", au->name, host->name,
1366 host->address, sx->buffer);
1367 break;
1368
1369 /* Internal problem, message in buffer. */
1370
1371 case ERROR:
1372 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1373 DEFER, FALSE);
1374 return ERROR;
1375 }
1376 return OK;
1377 }
1378
1379
1380
1381
1382 /* Do the client side of smtp-level authentication.
1383
1384 Arguments:
1385 sx smtp connection context
1386
1387 sx->buffer should have the EHLO response from server (gets overwritten)
1388
1389 Returns:
1390 OK Success, or failed (but not required): global "smtp_authenticated" set
1391 DEFER Failed authentication (and was required)
1392 ERROR Internal problem
1393
1394 FAIL_SEND Failed communications - transmit
1395 FAIL - response
1396 */
1397
1398 static int
1399 smtp_auth(smtp_context * sx)
1400 {
1401 host_item * host = sx->conn_args.host; /* host to deliver to */
1402 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1403 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1404 #ifdef EXPERIMENTAL_PIPE_CONNECT
1405 unsigned short authbits = tls_out.active.sock >= 0
1406 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1407 #endif
1408 uschar * fail_reason = US"server did not advertise AUTH support";
1409
1410 f.smtp_authenticated = FALSE;
1411 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1412
1413 if (!regex_AUTH)
1414 regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
1415
1416 /* Is the server offering AUTH? */
1417
1418 if ( sx->esmtp
1419 &&
1420 #ifdef EXPERIMENTAL_PIPE_CONNECT
1421 sx->early_pipe_active ? authbits
1422 :
1423 #endif
1424 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1425 )
1426 {
1427 uschar * names = NULL;
1428 expand_nmax = -1; /* reset */
1429
1430 #ifdef EXPERIMENTAL_PIPE_CONNECT
1431 if (!sx->early_pipe_active)
1432 #endif
1433 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1434
1435 /* Must not do this check until after we have saved the result of the
1436 regex match above as the check could be another RE. */
1437
1438 if ( require_auth == OK
1439 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1440 {
1441 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1442 fail_reason = US"no common mechanisms were found";
1443
1444 #ifdef EXPERIMENTAL_PIPE_CONNECT
1445 if (sx->early_pipe_active)
1446 {
1447 /* Scan our authenticators (which support use by a client and were offered
1448 by the server (checked at cache-write time)), not suppressed by
1449 client_condition. If one is found, attempt to authenticate by calling its
1450 client function. We are limited to supporting up to 16 authenticator
1451 public-names by the number of bits in a short. */
1452
1453 auth_instance * au;
1454 uschar bitnum;
1455 int rc;
1456
1457 for (bitnum = 0, au = auths;
1458 !f.smtp_authenticated && au && bitnum < 16;
1459 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1460 {
1461 if ( au->client_condition
1462 && !expand_check_condition(au->client_condition, au->name,
1463 US"client authenticator"))
1464 {
1465 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1466 au->name, "client_condition is false");
1467 continue;
1468 }
1469
1470 /* Found data for a listed mechanism. Call its client entry. Set
1471 a flag in the outblock so that data is overwritten after sending so
1472 that reflections don't show it. */
1473
1474 fail_reason = US"authentication attempt(s) failed";
1475
1476 if ((rc = try_authenticator(sx, au)) != OK)
1477 return rc;
1478 }
1479 }
1480 else
1481 #endif
1482
1483 /* Scan the configured authenticators looking for one which is configured
1484 for use as a client, which is not suppressed by client_condition, and
1485 whose name matches an authentication mechanism supported by the server.
1486 If one is found, attempt to authenticate by calling its client function.
1487 */
1488
1489 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1490 {
1491 uschar *p = names;
1492
1493 if ( !au->client
1494 || ( au->client_condition
1495 && !expand_check_condition(au->client_condition, au->name,
1496 US"client authenticator")))
1497 {
1498 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1499 au->name,
1500 (au->client)? "client_condition is false" :
1501 "not configured as a client");
1502 continue;
1503 }
1504
1505 /* Loop to scan supported server mechanisms */
1506
1507 while (*p)
1508 {
1509 int len = Ustrlen(au->public_name);
1510 int rc;
1511
1512 while (isspace(*p)) p++;
1513
1514 if (strncmpic(au->public_name, p, len) != 0 ||
1515 (p[len] != 0 && !isspace(p[len])))
1516 {
1517 while (*p != 0 && !isspace(*p)) p++;
1518 continue;
1519 }
1520
1521 /* Found data for a listed mechanism. Call its client entry. Set
1522 a flag in the outblock so that data is overwritten after sending so
1523 that reflections don't show it. */
1524
1525 fail_reason = US"authentication attempt(s) failed";
1526
1527 if ((rc = try_authenticator(sx, au)) != OK)
1528 return rc;
1529
1530 break; /* If not authenticated, try next authenticator */
1531 } /* Loop for scanning supported server mechanisms */
1532 } /* Loop for further authenticators */
1533 }
1534 }
1535
1536 /* If we haven't authenticated, but are required to, give up. */
1537
1538 if (require_auth == OK && !f.smtp_authenticated)
1539 {
1540 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1541 string_sprintf("authentication required but %s", fail_reason), DEFER,
1542 FALSE);
1543 return DEFER;
1544 }
1545
1546 return OK;
1547 }
1548
1549
1550 /* Construct AUTH appendix string for MAIL TO */
1551 /*
1552 Arguments
1553 buffer to build string
1554 addrlist chain of potential addresses to deliver
1555 ob transport options
1556
1557 Globals f.smtp_authenticated
1558 client_authenticated_sender
1559 Return True on error, otherwise buffer has (possibly empty) terminated string
1560 */
1561
1562 BOOL
1563 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1564 smtp_transport_options_block *ob)
1565 {
1566 uschar *local_authenticated_sender = authenticated_sender;
1567
1568 #ifdef notdef
1569 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1570 #endif
1571
1572 if (ob->authenticated_sender != NULL)
1573 {
1574 uschar *new = expand_string(ob->authenticated_sender);
1575 if (new == NULL)
1576 {
1577 if (!f.expand_string_forcedfail)
1578 {
1579 uschar *message = string_sprintf("failed to expand "
1580 "authenticated_sender: %s", expand_string_message);
1581 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1582 return TRUE;
1583 }
1584 }
1585 else if (new[0] != 0) local_authenticated_sender = new;
1586 }
1587
1588 /* Add the authenticated sender address if present */
1589
1590 if ((f.smtp_authenticated || ob->authenticated_sender_force) &&
1591 local_authenticated_sender != NULL)
1592 {
1593 string_format(buffer, bufsize, " AUTH=%s",
1594 auth_xtextencode(local_authenticated_sender,
1595 Ustrlen(local_authenticated_sender)));
1596 client_authenticated_sender = string_copy(local_authenticated_sender);
1597 }
1598 else
1599 *buffer= 0;
1600
1601 return FALSE;
1602 }
1603
1604
1605
1606 #ifdef SUPPORT_DANE
1607 /* Lookup TLSA record for host/port.
1608 Return: OK success with dnssec; DANE mode
1609 DEFER Do not use this host now, may retry later
1610 FAIL_FORCED No TLSA record; DANE not usable
1611 FAIL Do not use this connection
1612 */
1613
1614 int
1615 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1616 {
1617 /* move this out to host.c given the similarity to dns_lookup() ? */
1618 uschar buffer[300];
1619 const uschar * fullname = buffer;
1620 int rc;
1621 BOOL sec;
1622
1623 /* TLSA lookup string */
1624 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1625
1626 rc = dns_lookup(dnsa, buffer, T_TLSA, &fullname);
1627 sec = dns_is_secure(dnsa);
1628 DEBUG(D_transport)
1629 debug_printf("TLSA lookup ret %d %sDNSSEC\n", rc, sec ? "" : "not ");
1630
1631 switch (rc)
1632 {
1633 case DNS_AGAIN:
1634 return DEFER; /* just defer this TLS'd conn */
1635
1636 case DNS_SUCCEED:
1637 if (sec)
1638 {
1639 DEBUG(D_transport)
1640 {
1641 dns_scan dnss;
1642 for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
1643 rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
1644 if (rr->type == T_TLSA && rr->size > 3)
1645 {
1646 uint16_t payload_length = rr->size - 3;
1647 uschar s[MAX_TLSA_EXPANDED_SIZE], * sp = s, * p = US rr->data;
1648
1649 sp += sprintf(CS sp, "%d ", *p++); /* usage */
1650 sp += sprintf(CS sp, "%d ", *p++); /* selector */
1651 sp += sprintf(CS sp, "%d ", *p++); /* matchtype */
1652 while (payload_length-- > 0 && sp-s < (MAX_TLSA_EXPANDED_SIZE - 4))
1653 sp += sprintf(CS sp, "%02x", *p++);
1654
1655 debug_printf(" %s\n", s);
1656 }
1657 }
1658 return OK;
1659 }
1660 log_write(0, LOG_MAIN,
1661 "DANE error: TLSA lookup for %s not DNSSEC", host->name);
1662 /*FALLTRHOUGH*/
1663
1664 case DNS_NODATA: /* no TLSA RR for this lookup */
1665 case DNS_NOMATCH: /* no records at all for this lookup */
1666 return dane_required ? FAIL : FAIL_FORCED;
1667
1668 default:
1669 case DNS_FAIL:
1670 return dane_required ? FAIL : DEFER;
1671 }
1672 }
1673 #endif
1674
1675
1676
1677 typedef struct smtp_compare_s
1678 {
1679 uschar *current_sender_address;
1680 struct transport_instance *tblock;
1681 } smtp_compare_t;
1682
1683
1684 /* Create a unique string that identifies this message, it is based on
1685 sender_address, helo_data and tls_certificate if enabled.
1686 */
1687
1688 static uschar *
1689 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1690 {
1691 address_item * addr1;
1692 uschar * if1 = US"";
1693 uschar * helo1 = US"";
1694 #ifndef DISABLE_TLS
1695 uschar * tlsc1 = US"";
1696 #endif
1697 uschar * save_sender_address = sender_address;
1698 uschar * local_identity = NULL;
1699 smtp_transport_options_block * ob = SOB tblock->options_block;
1700
1701 sender_address = sender;
1702
1703 addr1 = deliver_make_addr (sender, TRUE);
1704 deliver_set_expansions(addr1);
1705
1706 if (ob->interface)
1707 if1 = expand_string(ob->interface);
1708
1709 if (ob->helo_data)
1710 helo1 = expand_string(ob->helo_data);
1711
1712 #ifndef DISABLE_TLS
1713 if (ob->tls_certificate)
1714 tlsc1 = expand_string(ob->tls_certificate);
1715 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1716 #else
1717 local_identity = string_sprintf ("%s^%s", if1, helo1);
1718 #endif
1719
1720 deliver_set_expansions(NULL);
1721 sender_address = save_sender_address;
1722
1723 return local_identity;
1724 }
1725
1726
1727
1728 /* This routine is a callback that is called from transport_check_waiting.
1729 This function will evaluate the incoming message versus the previous
1730 message. If the incoming message is using a different local identity then
1731 we will veto this new message. */
1732
1733 static BOOL
1734 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1735 {
1736 uschar * message_local_identity,
1737 * current_local_identity,
1738 * new_sender_address;
1739
1740 current_local_identity =
1741 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1742
1743 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1744 return 0;
1745
1746 message_local_identity =
1747 smtp_local_identity(new_sender_address, s_compare->tblock);
1748
1749 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1750 }
1751
1752
1753
1754 static unsigned
1755 ehlo_response(uschar * buf, unsigned checks)
1756 {
1757 size_t bsize = Ustrlen(buf);
1758
1759 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1760
1761 #ifndef DISABLE_TLS
1762 if ( checks & OPTION_TLS
1763 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1764 #endif
1765 checks &= ~OPTION_TLS;
1766
1767 if ( checks & OPTION_IGNQ
1768 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1769 PCRE_EOPT, NULL, 0) < 0)
1770 checks &= ~OPTION_IGNQ;
1771
1772 if ( checks & OPTION_CHUNKING
1773 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1774 checks &= ~OPTION_CHUNKING;
1775
1776 #ifndef DISABLE_PRDR
1777 if ( checks & OPTION_PRDR
1778 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1779 #endif
1780 checks &= ~OPTION_PRDR;
1781
1782 #ifdef SUPPORT_I18N
1783 if ( checks & OPTION_UTF8
1784 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1785 #endif
1786 checks &= ~OPTION_UTF8;
1787
1788 if ( checks & OPTION_DSN
1789 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1790 checks &= ~OPTION_DSN;
1791
1792 if ( checks & OPTION_PIPE
1793 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1794 PCRE_EOPT, NULL, 0) < 0)
1795 checks &= ~OPTION_PIPE;
1796
1797 if ( checks & OPTION_SIZE
1798 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1799 checks &= ~OPTION_SIZE;
1800
1801 #ifdef EXPERIMENTAL_PIPE_CONNECT
1802 if ( checks & OPTION_EARLY_PIPE
1803 && pcre_exec(regex_EARLY_PIPE, NULL, CS buf, bsize, 0,
1804 PCRE_EOPT, NULL, 0) < 0)
1805 #endif
1806 checks &= ~OPTION_EARLY_PIPE;
1807
1808 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1809 return checks;
1810 }
1811
1812
1813
1814 /* Callback for emitting a BDAT data chunk header.
1815
1816 If given a nonzero size, first flush any buffered SMTP commands
1817 then emit the command.
1818
1819 Reap previous SMTP command responses if requested, and always reap
1820 the response from a previous BDAT command.
1821
1822 Args:
1823 tctx transport context
1824 chunk_size value for SMTP BDAT command
1825 flags
1826 tc_chunk_last add LAST option to SMTP BDAT command
1827 tc_reap_prev reap response to previous SMTP commands
1828
1829 Returns:
1830 OK or ERROR
1831 DEFER TLS error on first read (EHLO-resp); errno set
1832 */
1833
1834 static int
1835 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1836 unsigned flags)
1837 {
1838 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1839 smtp_context * sx = tctx->smtp_context;
1840 int cmd_count = 0;
1841 int prev_cmd_count;
1842
1843 /* Write SMTP chunk header command. If not reaping responses, note that
1844 there may be more writes (like, the chunk data) done soon. */
1845
1846 if (chunk_size > 0)
1847 {
1848 #ifdef EXPERIMENTAL_PIPE_CONNECT
1849 BOOL new_conn = !!(sx->outblock.conn_args);
1850 #endif
1851 if((cmd_count = smtp_write_command(sx,
1852 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1853 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1854 ) < 0) return ERROR;
1855 if (flags & tc_chunk_last)
1856 data_command = string_copy(big_buffer); /* Save for later error message */
1857 #ifdef EXPERIMENTAL_PIPE_CONNECT
1858 /* That command write could have been the one that made the connection.
1859 Copy the fd from the client conn ctx (smtp transport specific) to the
1860 generic transport ctx. */
1861
1862 if (new_conn)
1863 tctx->u.fd = sx->outblock.cctx->sock;
1864 #endif
1865 }
1866
1867 prev_cmd_count = cmd_count += sx->cmd_count;
1868
1869 /* Reap responses for any previous, but not one we just emitted */
1870
1871 if (chunk_size > 0)
1872 prev_cmd_count--;
1873 if (sx->pending_BDAT)
1874 prev_cmd_count--;
1875
1876 if (flags & tc_reap_prev && prev_cmd_count > 0)
1877 {
1878 DEBUG(D_transport) debug_printf("look for %d responses"
1879 " for previous pipelined cmds\n", prev_cmd_count);
1880
1881 switch(sync_responses(sx, prev_cmd_count, 0))
1882 {
1883 case 1: /* 2xx (only) => OK */
1884 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1885 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1886 case 0: break; /* No 2xx or 5xx, but no probs */
1887
1888 case -5: errno = ERRNO_TLSFAILURE;
1889 return DEFER;
1890 #ifdef EXPERIMENTAL_PIPE_CONNECT
1891 case -4: /* non-2xx for pipelined banner or EHLO */
1892 #endif
1893 case -1: /* Timeout on RCPT */
1894 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1895 }
1896 cmd_count = 1;
1897 if (!sx->pending_BDAT)
1898 pipelining_active = FALSE;
1899 }
1900
1901 /* Reap response for an outstanding BDAT */
1902
1903 if (sx->pending_BDAT)
1904 {
1905 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1906
1907 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
1908 ob->command_timeout))
1909 {
1910 if (errno == 0 && sx->buffer[0] == '4')
1911 {
1912 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1913 sx->addrlist->more_errno |=
1914 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1915 }
1916 return ERROR;
1917 }
1918 cmd_count--;
1919 sx->pending_BDAT = FALSE;
1920 pipelining_active = FALSE;
1921 }
1922 else if (chunk_size > 0)
1923 sx->pending_BDAT = TRUE;
1924
1925
1926 sx->cmd_count = cmd_count;
1927 return OK;
1928 }
1929
1930
1931
1932
1933
1934 /*************************************************
1935 * Make connection for given message *
1936 *************************************************/
1937
1938 /*
1939 Arguments:
1940 ctx connection context
1941 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1942 a second attempt after TLS initialization fails
1943
1944 Returns: OK - the connection was made and the delivery attempted;
1945 fd is set in the conn context, tls_out set up.
1946 DEFER - the connection could not be made, or something failed
1947 while setting up the SMTP session, or there was a
1948 non-message-specific error, such as a timeout.
1949 ERROR - helo_data or add_headers or authenticated_sender is
1950 specified for this transport, and the string failed
1951 to expand
1952 */
1953 int
1954 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1955 {
1956 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
1957 BOOL pass_message = FALSE;
1958 uschar * message = NULL;
1959 int yield = OK;
1960 int rc;
1961 #ifndef DISABLE_TLS
1962 uschar * tls_errstr;
1963 #endif
1964
1965 sx->conn_args.ob = ob;
1966
1967 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1968 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
1969 sx->ok = FALSE;
1970 sx->send_rset = TRUE;
1971 sx->send_quit = TRUE;
1972 sx->setting_up = TRUE;
1973 sx->esmtp = TRUE;
1974 sx->esmtp_sent = FALSE;
1975 #ifdef SUPPORT_I18N
1976 sx->utf8_needed = FALSE;
1977 #endif
1978 sx->dsn_all_lasthop = TRUE;
1979 #ifdef SUPPORT_DANE
1980 sx->conn_args.dane = FALSE;
1981 sx->dane_required =
1982 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
1983 #endif
1984 #ifdef EXPERIMENTAL_PIPE_CONNECT
1985 sx->early_pipe_active = sx->early_pipe_ok = FALSE;
1986 sx->ehlo_resp.cleartext_features = sx->ehlo_resp.crypted_features = 0;
1987 sx->pending_BANNER = sx->pending_EHLO = FALSE;
1988 #endif
1989
1990 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1991 sx->peer_offered = 0;
1992 sx->avoid_option = 0;
1993 sx->igquotstr = US"";
1994 if (!sx->helo_data) sx->helo_data = ob->helo_data;
1995 #ifdef EXPERIMENTAL_DSN_INFO
1996 sx->smtp_greeting = NULL;
1997 sx->helo_response = NULL;
1998 #endif
1999
2000 smtp_command = US"initial connection";
2001 sx->buffer[0] = '\0';
2002
2003 /* Set up the buffer for reading SMTP response packets. */
2004
2005 sx->inblock.buffer = sx->inbuffer;
2006 sx->inblock.buffersize = sizeof(sx->inbuffer);
2007 sx->inblock.ptr = sx->inbuffer;
2008 sx->inblock.ptrend = sx->inbuffer;
2009
2010 /* Set up the buffer for holding SMTP commands while pipelining */
2011
2012 sx->outblock.buffer = sx->outbuffer;
2013 sx->outblock.buffersize = sizeof(sx->outbuffer);
2014 sx->outblock.ptr = sx->outbuffer;
2015 sx->outblock.cmd_count = 0;
2016 sx->outblock.authenticating = FALSE;
2017 sx->outblock.conn_args = NULL;
2018
2019 /* Reset the parameters of a TLS session. */
2020
2021 tls_out.bits = 0;
2022 tls_out.cipher = NULL; /* the one we may use for this transport */
2023 tls_out.ourcert = NULL;
2024 tls_out.peercert = NULL;
2025 tls_out.peerdn = NULL;
2026 #ifdef USE_OPENSSL
2027 tls_out.sni = NULL;
2028 #endif
2029 tls_out.ocsp = OCSP_NOT_REQ;
2030 #ifdef EXPERIMENTAL_TLS_RESUME
2031 tls_out.resumption = 0;
2032 #endif
2033
2034 /* Flip the legacy TLS-related variables over to the outbound set in case
2035 they're used in the context of the transport. Don't bother resetting
2036 afterward (when being used by a transport) as we're in a subprocess.
2037 For verify, unflipped once the callout is dealt with */
2038
2039 tls_modify_variables(&tls_out);
2040
2041 #ifdef DISABLE_TLS
2042 if (sx->smtps)
2043 {
2044 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
2045 DEFER, FALSE);
2046 return ERROR;
2047 }
2048 #endif
2049
2050 /* Make a connection to the host if this isn't a continued delivery, and handle
2051 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2052 specially so they can be identified for retries. */
2053
2054 if (!continue_hostname)
2055 {
2056 if (sx->verify)
2057 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2058
2059 /* Get the actual port the connection will use, into sx->conn_args.host */
2060
2061 smtp_port_for_connect(sx->conn_args.host, sx->port);
2062
2063 #ifdef SUPPORT_DANE
2064 /* Do TLSA lookup for DANE */
2065 {
2066 tls_out.dane_verified = FALSE;
2067 tls_out.tlsa_usage = 0;
2068
2069 if (sx->conn_args.host->dnssec == DS_YES)
2070 {
2071 if( sx->dane_required
2072 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2073 )
2074 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2075 {
2076 case OK: sx->conn_args.dane = TRUE;
2077 ob->tls_tempfail_tryclear = FALSE;
2078 break;
2079 case FAIL_FORCED: break;
2080 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2081 string_sprintf("DANE error: tlsa lookup %s",
2082 rc_to_string(rc)),
2083 rc, FALSE);
2084 # ifndef DISABLE_EVENT
2085 (void) event_raise(sx->conn_args.tblock->event_action,
2086 US"dane:fail", sx->dane_required
2087 ? US"dane-required" : US"dnssec-invalid");
2088 # endif
2089 return rc;
2090 }
2091 }
2092 else if (sx->dane_required)
2093 {
2094 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2095 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2096 FAIL, FALSE);
2097 # ifndef DISABLE_EVENT
2098 (void) event_raise(sx->conn_args.tblock->event_action,
2099 US"dane:fail", US"dane-required");
2100 # endif
2101 return FAIL;
2102 }
2103 }
2104 #endif /*DANE*/
2105
2106 /* Make the TCP connection */
2107
2108 sx->cctx.tls_ctx = NULL;
2109 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2110 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2111
2112 #ifdef EXPERIMENTAL_PIPE_CONNECT
2113 if (verify_check_given_host(CUSS &ob->hosts_pipe_connect, sx->conn_args.host) == OK)
2114 {
2115 sx->early_pipe_ok = TRUE;
2116 if ( read_ehlo_cache_entry(sx)
2117 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2118 {
2119 DEBUG(D_transport) debug_printf("Using cached cleartext PIPE_CONNECT\n");
2120 sx->early_pipe_active = TRUE;
2121 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2122 }
2123 }
2124
2125 if (sx->early_pipe_active)
2126 sx->outblock.conn_args = &sx->conn_args;
2127 else
2128 #endif
2129 {
2130 if ((sx->cctx.sock = smtp_connect(&sx->conn_args, NULL)) < 0)
2131 {
2132 set_errno_nohost(sx->addrlist,
2133 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2134 sx->verify ? US strerror(errno) : NULL,
2135 DEFER, FALSE);
2136 sx->send_quit = FALSE;
2137 return DEFER;
2138 }
2139 }
2140 /* Expand the greeting message while waiting for the initial response. (Makes
2141 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2142 delayed till here so that $sending_interface and $sending_port are set. */
2143 /*XXX early-pipe: they still will not be. Is there any way to find out what they
2144 will be? Somehow I doubt it. */
2145
2146 if (sx->helo_data)
2147 if (!(sx->helo_data = expand_string(sx->helo_data)))
2148 if (sx->verify)
2149 log_write(0, LOG_MAIN|LOG_PANIC,
2150 "<%s>: failed to expand transport's helo_data value for callout: %s",
2151 sx->addrlist->address, expand_string_message);
2152
2153 #ifdef SUPPORT_I18N
2154 if (sx->helo_data)
2155 {
2156 expand_string_message = NULL;
2157 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2158 &expand_string_message)),
2159 expand_string_message)
2160 if (sx->verify)
2161 log_write(0, LOG_MAIN|LOG_PANIC,
2162 "<%s>: failed to expand transport's helo_data value for callout: %s",
2163 sx->addrlist->address, expand_string_message);
2164 else
2165 sx->helo_data = NULL;
2166 }
2167 #endif
2168
2169 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2170 is nevertheless a reasonably clean way of programming this kind of logic,
2171 where you want to escape on any error. */
2172
2173 if (!sx->smtps)
2174 {
2175 #ifdef EXPERIMENTAL_PIPE_CONNECT
2176 if (sx->early_pipe_active)
2177 {
2178 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2179 sx->outblock.cmd_count = 1;
2180 }
2181 else
2182 #endif
2183 {
2184 #ifdef TCP_QUICKACK
2185 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2186 sizeof(off));
2187 #endif
2188 if (!smtp_reap_banner(sx))
2189 goto RESPONSE_FAILED;
2190 }
2191
2192 #ifndef DISABLE_EVENT
2193 {
2194 uschar * s;
2195 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2196 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2197 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer);
2198 if (s)
2199 {
2200 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2201 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2202 DEFER, FALSE);
2203 yield = DEFER;
2204 goto SEND_QUIT;
2205 }
2206 }
2207 #endif
2208
2209 /* Now check if the helo_data expansion went well, and sign off cleanly if
2210 it didn't. */
2211
2212 if (!sx->helo_data)
2213 {
2214 message = string_sprintf("failed to expand helo_data: %s",
2215 expand_string_message);
2216 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2217 yield = DEFER;
2218 goto SEND_QUIT;
2219 }
2220 }
2221
2222 /** Debugging without sending a message
2223 sx->addrlist->transport_return = DEFER;
2224 goto SEND_QUIT;
2225 **/
2226
2227 /* Errors that occur after this point follow an SMTP command, which is
2228 left in big_buffer by smtp_write_command() for use in error messages. */
2229
2230 smtp_command = big_buffer;
2231
2232 /* Tell the remote who we are...
2233
2234 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2235 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2236 greeting is of this form. The assumption was that the far end supports it
2237 properly... but experience shows that there are some that give 5xx responses,
2238 even though the banner includes "ESMTP" (there's a bloody-minded one that
2239 says "ESMTP not spoken here"). Cope with that case.
2240
2241 September 2000: Time has passed, and it seems reasonable now to always send
2242 EHLO at the start. It is also convenient to make the change while installing
2243 the TLS stuff.
2244
2245 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2246 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2247 would be no way to send out the mails, so there is now a host list
2248 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2249 PIPELINING problem as well. Maybe it can also be useful to cure other
2250 problems with broken servers.
2251
2252 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2253 Then somebody tried it with a Microsoft mailer... It seems that all other
2254 mailers use upper case for some reason (the RFC is quite clear about case
2255 independence) so, for peace of mind, I gave in. */
2256
2257 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2258
2259 /* Alas; be careful, since this goto is not an error-out, so conceivably
2260 we might set data between here and the target which we assume to exist
2261 and be usable. I can see this coming back to bite us. */
2262 #ifndef DISABLE_TLS
2263 if (sx->smtps)
2264 {
2265 smtp_peer_options |= OPTION_TLS;
2266 suppress_tls = FALSE;
2267 ob->tls_tempfail_tryclear = FALSE;
2268 smtp_command = US"SSL-on-connect";
2269 goto TLS_NEGOTIATE;
2270 }
2271 #endif
2272
2273 if (sx->esmtp)
2274 {
2275 if (smtp_write_command(sx,
2276 #ifdef EXPERIMENTAL_PIPE_CONNECT
2277 sx->early_pipe_active ? SCMD_BUFFER :
2278 #endif
2279 SCMD_FLUSH,
2280 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2281 goto SEND_FAILED;
2282 sx->esmtp_sent = TRUE;
2283
2284 #ifdef EXPERIMENTAL_PIPE_CONNECT
2285 if (sx->early_pipe_active)
2286 {
2287 sx->pending_EHLO = TRUE;
2288
2289 /* If we have too many authenticators to handle and might need to AUTH
2290 for this transport, pipeline no further as we will need the
2291 list of auth methods offered. Reap the banner and EHLO. */
2292
2293 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2294 && f.smtp_in_early_pipe_no_auth)
2295 {
2296 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2297 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2298 goto SEND_FAILED;
2299 if (sync_responses(sx, 2, 0) != 0)
2300 {
2301 HDEBUG(D_transport)
2302 debug_printf("failed reaping pipelined cmd responses\n");
2303 goto RESPONSE_FAILED;
2304 }
2305 sx->early_pipe_active = FALSE;
2306 }
2307 }
2308 else
2309 #endif
2310 if (!smtp_reap_ehlo(sx))
2311 goto RESPONSE_FAILED;
2312 }
2313 else
2314 DEBUG(D_transport)
2315 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2316
2317 #ifdef EXPERIMENTAL_PIPE_CONNECT
2318 if (!sx->early_pipe_active)
2319 #endif
2320 if (!sx->esmtp)
2321 {
2322 BOOL good_response;
2323 int n = sizeof(sx->buffer);
2324 uschar * rsp = sx->buffer;
2325
2326 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
2327 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
2328
2329 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2330 goto SEND_FAILED;
2331 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2332 #ifdef EXPERIMENTAL_DSN_INFO
2333 sx->helo_response = string_copy(rsp);
2334 #endif
2335 if (!good_response)
2336 {
2337 /* Handle special logging for a closed connection after HELO
2338 when had previously sent EHLO */
2339
2340 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2341 {
2342 errno = ERRNO_SMTPCLOSED;
2343 goto EHLOHELO_FAILED;
2344 }
2345 memmove(sx->buffer, rsp, Ustrlen(rsp));
2346 goto RESPONSE_FAILED;
2347 }
2348 }
2349
2350 if (sx->esmtp || sx->lmtp)
2351 {
2352 #ifdef EXPERIMENTAL_PIPE_CONNECT
2353 if (!sx->early_pipe_active)
2354 #endif
2355 {
2356 sx->peer_offered = ehlo_response(sx->buffer,
2357 OPTION_TLS /* others checked later */
2358 #ifdef EXPERIMENTAL_PIPE_CONNECT
2359 | (sx->early_pipe_ok
2360 ? OPTION_IGNQ
2361 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2362 #ifdef SUPPORT_I18N
2363 | OPTION_UTF8
2364 #endif
2365 | OPTION_EARLY_PIPE
2366 : 0
2367 )
2368 #endif
2369 );
2370 #ifdef EXPERIMENTAL_PIPE_CONNECT
2371 if (sx->early_pipe_ok)
2372 {
2373 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2374
2375 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2376 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2377 {
2378 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2379 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2380 write_ehlo_cache_entry(sx);
2381 }
2382 }
2383 #endif
2384 }
2385
2386 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2387
2388 #ifndef DISABLE_TLS
2389 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2390 #endif
2391 }
2392 }
2393
2394 /* For continuing deliveries down the same channel, having re-exec'd the socket
2395 is the standard input; for a socket held open from verify it is recorded
2396 in the cutthrough context block. Either way we don't need to redo EHLO here
2397 (but may need to do so for TLS - see below).
2398 Set up the pointer to where subsequent commands will be left, for
2399 error messages. Note that smtp_peer_options will have been
2400 set from the command line if they were set in the process that passed the
2401 connection on. */
2402
2403 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2404 as the continue goes via transport_pass_socket() and doublefork and exec.
2405 It does not wait. Unclear how we keep separate host's responses
2406 separate - we could match up by host ip+port as a bodge. */
2407
2408 else
2409 {
2410 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2411 {
2412 sx->cctx = cutthrough.cctx;
2413 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2414 }
2415 else
2416 {
2417 sx->cctx.sock = 0; /* stdin */
2418 sx->cctx.tls_ctx = NULL;
2419 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2420 }
2421 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2422 smtp_command = big_buffer;
2423 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2424
2425 /* For a continued connection with TLS being proxied for us, or a
2426 held-open verify connection with TLS, nothing more to do. */
2427
2428 if ( continue_proxy_cipher
2429 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2430 && cutthrough.is_tls)
2431 )
2432 {
2433 sx->peer_offered = smtp_peer_options;
2434 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2435 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2436 continue_proxy_cipher ? "proxied" : "verify conn with");
2437 return OK;
2438 }
2439 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2440 }
2441
2442 /* If TLS is available on this connection, whether continued or not, attempt to
2443 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2444 send another EHLO - the server may give a different answer in secure mode. We
2445 use a separate buffer for reading the response to STARTTLS so that if it is
2446 negative, the original EHLO data is available for subsequent analysis, should
2447 the client not be required to use TLS. If the response is bad, copy the buffer
2448 for error analysis. */
2449
2450 #ifndef DISABLE_TLS
2451 if ( smtp_peer_options & OPTION_TLS
2452 && !suppress_tls
2453 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2454 && ( !sx->verify
2455 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2456 ) )
2457 {
2458 uschar buffer2[4096];
2459
2460 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2461 goto SEND_FAILED;
2462
2463 #ifdef EXPERIMENTAL_PIPE_CONNECT
2464 /* If doing early-pipelining reap the banner and EHLO-response but leave
2465 the response for the STARTTLS we just sent alone. */
2466
2467 if (sx->early_pipe_active && sync_responses(sx, 2, 0) != 0)
2468 {
2469 HDEBUG(D_transport)
2470 debug_printf("failed reaping pipelined cmd responses\n");
2471 goto RESPONSE_FAILED;
2472 }
2473 #endif
2474
2475 /* If there is an I/O error, transmission of this message is deferred. If
2476 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2477 false, we also defer. However, if there is a temporary rejection of STARTTLS
2478 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2479 STARTTLS, we carry on. This means we will try to send the message in clear,
2480 unless the host is in hosts_require_tls (tested below). */
2481
2482 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2483 {
2484 if ( errno != 0
2485 || buffer2[0] == 0
2486 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2487 )
2488 {
2489 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2490 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2491 goto RESPONSE_FAILED;
2492 }
2493 }
2494
2495 /* STARTTLS accepted: try to negotiate a TLS session. */
2496
2497 else
2498 TLS_NEGOTIATE:
2499 {
2500 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2501 {
2502 /* TLS negotiation failed; give an error. From outside, this function may
2503 be called again to try in clear on a new connection, if the options permit
2504 it for this host. */
2505 #ifdef USE_GNUTLS
2506 GNUTLS_CONN_FAILED:
2507 #endif
2508 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2509
2510 # ifdef SUPPORT_DANE
2511 if (sx->conn_args.dane)
2512 {
2513 log_write(0, LOG_MAIN,
2514 "DANE attempt failed; TLS connection to %s [%s]: %s",
2515 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2516 # ifndef DISABLE_EVENT
2517 (void) event_raise(sx->conn_args.tblock->event_action,
2518 US"dane:fail", US"validation-failure"); /* could do with better detail */
2519 # endif
2520 }
2521 # endif
2522
2523 errno = ERRNO_TLSFAILURE;
2524 message = string_sprintf("TLS session: %s", tls_errstr);
2525 sx->send_quit = FALSE;
2526 goto TLS_FAILED;
2527 }
2528
2529 /* TLS session is set up */
2530
2531 smtp_peer_options_wrap = smtp_peer_options;
2532 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2533 if (addr->transport_return == PENDING_DEFER)
2534 {
2535 addr->cipher = tls_out.cipher;
2536 addr->ourcert = tls_out.ourcert;
2537 addr->peercert = tls_out.peercert;
2538 addr->peerdn = tls_out.peerdn;
2539 addr->ocsp = tls_out.ocsp;
2540 }
2541 }
2542 }
2543
2544 /* if smtps, we'll have smtp_command set to something else; always safe to
2545 reset it here. */
2546 smtp_command = big_buffer;
2547
2548 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2549 helo_data is null, we are dealing with a connection that was passed from
2550 another process, and so we won't have expanded helo_data above. We have to
2551 expand it here. $sending_ip_address and $sending_port are set up right at the
2552 start of the Exim process (in exim.c). */
2553
2554 if (tls_out.active.sock >= 0)
2555 {
2556 uschar * greeting_cmd;
2557
2558 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2559 {
2560 uschar *message = string_sprintf("failed to expand helo_data: %s",
2561 expand_string_message);
2562 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2563 yield = DEFER;
2564 goto SEND_QUIT;
2565 }
2566
2567 #ifdef EXPERIMENTAL_PIPE_CONNECT
2568 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2569 We're unlikely to get the group sent and delivered before the server sends its
2570 banner, but it's still worth sending as a group.
2571 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2572 the reverse. */
2573
2574 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2575 {
2576 sx->peer_offered = sx->ehlo_resp.crypted_features;
2577 if ((sx->early_pipe_active =
2578 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2579 DEBUG(D_transport) debug_printf("Using cached crypted PIPE_CONNECT\n");
2580 }
2581 #endif
2582
2583 /* For SMTPS we need to wait for the initial OK response. */
2584 if (sx->smtps)
2585 #ifdef EXPERIMENTAL_PIPE_CONNECT
2586 if (sx->early_pipe_active)
2587 {
2588 sx->pending_BANNER = TRUE;
2589 sx->outblock.cmd_count = 1;
2590 }
2591 else
2592 #endif
2593 if (!smtp_reap_banner(sx))
2594 goto RESPONSE_FAILED;
2595
2596 if (sx->lmtp)
2597 greeting_cmd = US"LHLO";
2598 else if (sx->esmtp)
2599 greeting_cmd = US"EHLO";
2600 else
2601 {
2602 greeting_cmd = US"HELO";
2603 DEBUG(D_transport)
2604 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2605 }
2606
2607 if (smtp_write_command(sx,
2608 #ifdef EXPERIMENTAL_PIPE_CONNECT
2609 sx->early_pipe_active ? SCMD_BUFFER :
2610 #endif
2611 SCMD_FLUSH,
2612 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2613 goto SEND_FAILED;
2614
2615 #ifdef EXPERIMENTAL_PIPE_CONNECT
2616 if (sx->early_pipe_active)
2617 sx->pending_EHLO = TRUE;
2618 else
2619 #endif
2620 {
2621 if (!smtp_reap_ehlo(sx))
2622 #ifdef USE_GNUTLS
2623 {
2624 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2625 cert late, under TLS1.3 - which means here; the first time we try to
2626 receive crypted data. Treat it as if it was a connect-time failure.
2627 See also the early-pipe equivalent... which will be hard; every call
2628 to sync_responses will need to check the result.
2629 It would be nicer to have GnuTLS check the cert during the handshake.
2630 Can it do that, with all the flexibility we need? */
2631
2632 tls_errstr = US"error on first read";
2633 goto GNUTLS_CONN_FAILED;
2634 }
2635 #else
2636 goto RESPONSE_FAILED;
2637 #endif
2638 smtp_peer_options = 0;
2639 }
2640 }
2641
2642 /* If the host is required to use a secure channel, ensure that we
2643 have one. */
2644
2645 else if ( sx->smtps
2646 # ifdef SUPPORT_DANE
2647 || sx->conn_args.dane
2648 # endif
2649 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2650 )
2651 {
2652 errno = ERRNO_TLSREQUIRED;
2653 message = string_sprintf("a TLS session is required, but %s",
2654 smtp_peer_options & OPTION_TLS
2655 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2656 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2657 if (sx->conn_args.dane)
2658 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2659 smtp_peer_options & OPTION_TLS
2660 ? US"validation-failure" /* could do with better detail */
2661 : US"starttls-not-supported");
2662 # endif
2663 goto TLS_FAILED;
2664 }
2665 #endif /*DISABLE_TLS*/
2666
2667 /* If TLS is active, we have just started it up and re-done the EHLO command,
2668 so its response needs to be analyzed. If TLS is not active and this is a
2669 continued session down a previously-used socket, we haven't just done EHLO, so
2670 we skip this. */
2671
2672 if (continue_hostname == NULL
2673 #ifndef DISABLE_TLS
2674 || tls_out.active.sock >= 0
2675 #endif
2676 )
2677 {
2678 if (sx->esmtp || sx->lmtp)
2679 {
2680 #ifdef EXPERIMENTAL_PIPE_CONNECT
2681 if (!sx->early_pipe_active)
2682 #endif
2683 {
2684 sx->peer_offered = ehlo_response(sx->buffer,
2685 0 /* no TLS */
2686 #ifdef EXPERIMENTAL_PIPE_CONNECT
2687 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2688 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2689 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2690 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2691
2692 #else
2693
2694 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2695 | OPTION_CHUNKING
2696 | OPTION_PRDR
2697 # ifdef SUPPORT_I18N
2698 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2699 /*XXX if we hand peercaps on to continued-conn processes,
2700 must not depend on this addr */
2701 # endif
2702 | OPTION_DSN
2703 | OPTION_PIPE
2704 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2705 #endif
2706 );
2707 #ifdef EXPERIMENTAL_PIPE_CONNECT
2708 if (tls_out.active.sock >= 0)
2709 sx->ehlo_resp.crypted_features = sx->peer_offered;
2710 #endif
2711 }
2712
2713 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2714 lmtp_ignore_quota option was set. */
2715
2716 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2717
2718 /* If the response to EHLO specified support for the SIZE parameter, note
2719 this, provided size_addition is non-negative. */
2720
2721 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2722
2723 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2724 the current host, esmtp will be false, so PIPELINING can never be used. If
2725 the current host matches hosts_avoid_pipelining, don't do it. */
2726
2727 if ( sx->peer_offered & OPTION_PIPE
2728 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2729 smtp_peer_options |= OPTION_PIPE;
2730
2731 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2732 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2733
2734 if ( sx->peer_offered & OPTION_CHUNKING
2735 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) != OK)
2736 sx->peer_offered &= ~OPTION_CHUNKING;
2737
2738 if (sx->peer_offered & OPTION_CHUNKING)
2739 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2740
2741 #ifndef DISABLE_PRDR
2742 if ( sx->peer_offered & OPTION_PRDR
2743 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) != OK)
2744 sx->peer_offered &= ~OPTION_PRDR;
2745
2746 if (sx->peer_offered & OPTION_PRDR)
2747 DEBUG(D_transport) debug_printf("PRDR usable\n");
2748 #endif
2749
2750 /* Note if the server supports DSN */
2751 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2752 DEBUG(D_transport) debug_printf("%susing DSN\n",
2753 sx->peer_offered & OPTION_DSN ? "" : "not ");
2754
2755 #ifdef EXPERIMENTAL_PIPE_CONNECT
2756 if ( sx->early_pipe_ok
2757 && !sx->early_pipe_active
2758 && tls_out.active.sock >= 0
2759 && smtp_peer_options & OPTION_PIPE
2760 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
2761 & OPTION_EARLY_PIPE)
2762 {
2763 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2764 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
2765 write_ehlo_cache_entry(sx);
2766 }
2767 #endif
2768
2769 /* Note if the response to EHLO specifies support for the AUTH extension.
2770 If it has, check that this host is one we want to authenticate to, and do
2771 the business. The host name and address must be available when the
2772 authenticator's client driver is running. */
2773
2774 switch (yield = smtp_auth(sx))
2775 {
2776 default: goto SEND_QUIT;
2777 case OK: break;
2778 case FAIL_SEND: goto SEND_FAILED;
2779 case FAIL: goto RESPONSE_FAILED;
2780 }
2781 }
2782 }
2783 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2784
2785 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2786 message-specific. */
2787
2788 sx->setting_up = FALSE;
2789
2790 #ifdef SUPPORT_I18N
2791 if (sx->addrlist->prop.utf8_msg)
2792 {
2793 uschar * s;
2794
2795 /* If the transport sets a downconversion mode it overrides any set by ACL
2796 for the message. */
2797
2798 if ((s = ob->utf8_downconvert))
2799 {
2800 if (!(s = expand_string(s)))
2801 {
2802 message = string_sprintf("failed to expand utf8_downconvert: %s",
2803 expand_string_message);
2804 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2805 yield = DEFER;
2806 goto SEND_QUIT;
2807 }
2808 switch (*s)
2809 {
2810 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
2811 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2812 break;
2813 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
2814 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2815 break;
2816 case '-': if (s[1] == '1')
2817 {
2818 sx->addrlist->prop.utf8_downcvt = FALSE;
2819 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
2820 }
2821 break;
2822 }
2823 }
2824
2825 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2826 && !sx->addrlist->prop.utf8_downcvt_maybe;
2827 DEBUG(D_transport) if (!sx->utf8_needed)
2828 debug_printf("utf8: %s downconvert\n",
2829 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2830 }
2831
2832 /* If this is an international message we need the host to speak SMTPUTF8 */
2833 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2834 {
2835 errno = ERRNO_UTF8_FWD;
2836 goto RESPONSE_FAILED;
2837 }
2838 #endif /*SUPPORT_I18N*/
2839
2840 return OK;
2841
2842
2843 {
2844 int code;
2845
2846 RESPONSE_FAILED:
2847 message = NULL;
2848 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
2849 sx->buffer, &code, &message, &pass_message);
2850 yield = DEFER;
2851 goto FAILED;
2852
2853 SEND_FAILED:
2854 code = '4';
2855 message = US string_sprintf("send() to %s [%s] failed: %s",
2856 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
2857 sx->send_quit = FALSE;
2858 yield = DEFER;
2859 goto FAILED;
2860
2861 EHLOHELO_FAILED:
2862 code = '4';
2863 message = string_sprintf("Remote host closed connection in response to %s"
2864 " (EHLO response was: %s)", smtp_command, sx->buffer);
2865 sx->send_quit = FALSE;
2866 yield = DEFER;
2867 goto FAILED;
2868
2869 /* This label is jumped to directly when a TLS negotiation has failed,
2870 or was not done for a host for which it is required. Values will be set
2871 in message and errno, and setting_up will always be true. Treat as
2872 a temporary error. */
2873
2874 #ifndef DISABLE_TLS
2875 TLS_FAILED:
2876 code = '4', yield = DEFER;
2877 goto FAILED;
2878 #endif
2879
2880 /* The failure happened while setting up the call; see if the failure was
2881 a 5xx response (this will either be on connection, or following HELO - a 5xx
2882 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2883 fail all addresses, as this host is never going to accept them. For other
2884 errors during setting up (timeouts or whatever), defer all addresses, and
2885 yield DEFER, so that the host is not tried again for a while.
2886
2887 XXX This peeking for another host feels like a layering violation. We want
2888 to note the host as unusable, but down here we shouldn't know if this was
2889 the last host to try for the addr(list). Perhaps the upper layer should be
2890 the one to do set_errno() ? The problem is that currently the addr is where
2891 errno etc. are stashed, but until we run out of hosts to try the errors are
2892 host-specific. Maybe we should enhance the host_item definition? */
2893
2894 FAILED:
2895 sx->ok = FALSE; /* For when reached by GOTO */
2896 set_errno(sx->addrlist, errno, message,
2897 sx->conn_args.host->next
2898 ? DEFER
2899 : code == '5'
2900 #ifdef SUPPORT_I18N
2901 || errno == ERRNO_UTF8_FWD
2902 #endif
2903 ? FAIL : DEFER,
2904 pass_message, sx->conn_args.host
2905 #ifdef EXPERIMENTAL_DSN_INFO
2906 , sx->smtp_greeting, sx->helo_response
2907 #endif
2908 );
2909 }
2910
2911
2912 SEND_QUIT:
2913
2914 if (sx->send_quit)
2915 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
2916
2917 #ifndef DISABLE_TLS
2918 if (sx->cctx.tls_ctx)
2919 {
2920 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
2921 sx->cctx.tls_ctx = NULL;
2922 }
2923 #endif
2924
2925 /* Close the socket, and return the appropriate value, first setting
2926 works because the NULL setting is passed back to the calling process, and
2927 remote_max_parallel is forced to 1 when delivering over an existing connection,
2928 */
2929
2930 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2931 if (sx->send_quit)
2932 {
2933 shutdown(sx->cctx.sock, SHUT_WR);
2934 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
2935 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
2936 i--; /* drain socket */
2937 sx->send_quit = FALSE;
2938 }
2939 (void)close(sx->cctx.sock);
2940 sx->cctx.sock = -1;
2941
2942 #ifndef DISABLE_EVENT
2943 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL);
2944 #endif
2945
2946 continue_transport = NULL;
2947 continue_hostname = NULL;
2948 return yield;
2949 }
2950
2951
2952
2953
2954 /* Create the string of options that will be appended to the MAIL FROM:
2955 in the connection context buffer */
2956
2957 static int
2958 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2959 {
2960 uschar * p = sx->buffer;
2961 address_item * addr;
2962 int address_count;
2963
2964 *p = 0;
2965
2966 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2967 send it, adding something to the message size to allow for imprecision
2968 and things that get added en route. Exim keeps the number of lines
2969 in a message, so we can give an accurate value for the original message, but we
2970 need some additional to handle added headers. (Double "." characters don't get
2971 included in the count.) */
2972
2973 if ( message_size > 0
2974 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
2975 {
2976 /*XXX problem here under spool_files_wireformat?
2977 Or just forget about lines? Or inflate by a fixed proportion? */
2978
2979 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
2980 while (*p) p++;
2981 }
2982
2983 #ifndef DISABLE_PRDR
2984 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
2985 request that */
2986
2987 sx->prdr_active = FALSE;
2988 if (sx->peer_offered & OPTION_PRDR)
2989 for (address_item * addr = addrlist; addr; addr = addr->next)
2990 if (addr->transport_return == PENDING_DEFER)
2991 {
2992 for (addr = addr->next; addr; addr = addr->next)
2993 if (addr->transport_return == PENDING_DEFER)
2994 { /* at least two recipients to send */
2995 sx->prdr_active = TRUE;
2996 sprintf(CS p, " PRDR"); p += 5;
2997 break;
2998 }
2999 break;
3000 }
3001 #endif
3002
3003 #ifdef SUPPORT_I18N
3004 /* If it supports internationalised messages, and this meesage need that,
3005 request it */
3006
3007 if ( sx->peer_offered & OPTION_UTF8
3008 && addrlist->prop.utf8_msg
3009 && !addrlist->prop.utf8_downcvt
3010 )
3011 Ustrcpy(p, " SMTPUTF8"), p += 9;
3012 #endif
3013
3014 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3015 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3016 addr && address_count < sx->max_rcpt;
3017 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3018 {
3019 address_count++;
3020 if (!(addr->dsn_flags & rf_dsnlasthop))
3021 {
3022 sx->dsn_all_lasthop = FALSE;
3023 break;
3024 }
3025 }
3026
3027 /* Add any DSN flags to the mail command */
3028
3029 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3030 {
3031 if (dsn_ret == dsn_ret_hdrs)
3032 { Ustrcpy(p, " RET=HDRS"); p += 9; }
3033 else if (dsn_ret == dsn_ret_full)
3034 { Ustrcpy(p, " RET=FULL"); p += 9; }
3035
3036 if (dsn_envid)
3037 {
3038 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3039 while (*p) p++;
3040 }
3041 }
3042
3043 /* If an authenticated_sender override has been specified for this transport
3044 instance, expand it. If the expansion is forced to fail, and there was already
3045 an authenticated_sender for this message, the original value will be used.
3046 Other expansion failures are serious. An empty result is ignored, but there is
3047 otherwise no check - this feature is expected to be used with LMTP and other
3048 cases where non-standard addresses (e.g. without domains) might be required. */
3049
3050 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->conn_args.ob))
3051 return ERROR;
3052
3053 return OK;
3054 }
3055
3056
3057 static void
3058 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3059 {
3060 uschar * p = sx->buffer;
3061 *p = 0;
3062
3063 /* Add any DSN flags to the rcpt command */
3064
3065 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3066 {
3067 if (addr->dsn_flags & rf_dsnflags)
3068 {
3069 BOOL first = TRUE;
3070
3071 Ustrcpy(p, " NOTIFY=");
3072 while (*p) p++;
3073 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3074 {
3075 if (!first) *p++ = ',';
3076 first = FALSE;
3077 Ustrcpy(p, rf_names[i]);
3078 while (*p) p++;
3079 }
3080 }
3081
3082 if (addr->dsn_orcpt)
3083 {
3084 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3085 addr->dsn_orcpt);
3086 while (*p) p++;
3087 }
3088 }
3089 }
3090
3091
3092
3093 /*
3094 Return:
3095 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3096 -1 MAIL response error
3097 -2 any non-MAIL read i/o error
3098 -3 non-MAIL response timeout
3099 -4 internal error; channel still usable
3100 -5 transmit failed
3101 */
3102
3103 int
3104 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3105 {
3106 address_item * addr;
3107 int address_count;
3108 int rc;
3109
3110 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3111 {
3112 *yield = ERROR;
3113 return -4;
3114 }
3115
3116 /* From here until we send the DATA command, we can make use of PIPELINING
3117 if the server host supports it. The code has to be able to check the responses
3118 at any point, for when the buffer fills up, so we write it totally generally.
3119 When PIPELINING is off, each command written reports that it has flushed the
3120 buffer. */
3121
3122 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3123
3124 {
3125 uschar * s = sx->from_addr;
3126 #ifdef SUPPORT_I18N
3127 uschar * errstr = NULL;
3128
3129 /* If we must downconvert, do the from-address here. Remember we had to
3130 for the to-addresses (done below), and also (ugly) for re-doing when building
3131 the delivery log line. */
3132
3133 if ( sx->addrlist->prop.utf8_msg
3134 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3135 )
3136 {
3137 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3138 {
3139 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
3140 *yield = ERROR;
3141 return -4;
3142 }
3143 setflag(sx->addrlist, af_utf8_downcvt);
3144 }
3145 #endif
3146
3147 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3148 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3149 }
3150
3151 mail_command = string_copy(big_buffer); /* Save for later error message */
3152
3153 switch(rc)
3154 {
3155 case -1: /* Transmission error */
3156 return -5;
3157
3158 case +1: /* Cmd was sent */
3159 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3160 (SOB sx->conn_args.ob)->command_timeout))
3161 {
3162 if (errno == 0 && sx->buffer[0] == '4')
3163 {
3164 errno = ERRNO_MAIL4XX;
3165 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3166 }
3167 return -1;
3168 }
3169 sx->pending_MAIL = FALSE;
3170 break;
3171
3172 /* otherwise zero: command queued for pipeline */
3173 }
3174
3175 /* Pass over all the relevant recipient addresses for this host, which are the
3176 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3177 several before we have to read the responses for those seen so far. This
3178 checking is done by a subroutine because it also needs to be done at the end.
3179 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3180 the next one if not all are sent.
3181
3182 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3183 last address because we want to abort if any recipients have any kind of
3184 problem, temporary or permanent. We know that all recipient addresses will have
3185 the PENDING_DEFER status, because only one attempt is ever made, and we know
3186 that max_rcpt will be large, so all addresses will be done at once.
3187
3188 For verify we flush the pipeline after any (the only) rcpt address. */
3189
3190 for (addr = sx->first_addr, address_count = 0;
3191 addr && address_count < sx->max_rcpt;
3192 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3193 {
3194 int count;
3195 BOOL no_flush;
3196 uschar * rcpt_addr;
3197
3198 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3199 ? dsn_support_yes : dsn_support_no;
3200
3201 address_count++;
3202 no_flush = pipelining_active && !sx->verify
3203 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3204
3205 build_rcptcmd_options(sx, addr);
3206
3207 /* Now send the RCPT command, and process outstanding responses when
3208 necessary. After a timeout on RCPT, we just end the function, leaving the
3209 yield as OK, because this error can often mean that there is a problem with
3210 just one address, so we don't want to delay the host. */
3211
3212 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3213
3214 #ifdef SUPPORT_I18N
3215 if ( testflag(sx->addrlist, af_utf8_downcvt)
3216 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3217 )
3218 {
3219 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3220 errno = ERRNO_EXPANDFAIL;
3221 return -5; /*XXX too harsh? */
3222 }
3223 #endif
3224
3225 count = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3226 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3227
3228 if (count < 0) return -5;
3229 if (count > 0)
3230 {
3231 switch(sync_responses(sx, count, 0))
3232 {
3233 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3234 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3235 break;
3236
3237 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3238 if (!sx->lmtp) /* can't tell about progress yet */
3239 sx->completed_addr = TRUE;
3240 case 0: /* No 2xx or 5xx, but no probs */
3241 break;
3242
3243 case -1: return -3; /* Timeout on RCPT */
3244 case -2: return -2; /* non-MAIL read i/o error */
3245 default: return -1; /* any MAIL error */
3246
3247 #ifdef EXPERIMENTAL_PIPE_CONNECT
3248 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3249 case -5: return -1; /* TLS first-read error */
3250 #endif
3251 }
3252 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
3253 }
3254 } /* Loop for next address */
3255
3256 sx->next_addr = addr;
3257 return 0;
3258 }
3259
3260
3261 #ifndef DISABLE_TLS
3262 /*****************************************************
3263 * Proxy TLS connection for another transport process *
3264 ******************************************************/
3265 /*
3266 Close the unused end of the pipe, fork once more, then use the given buffer
3267 as a staging area, and select on both the given fd and the TLS'd client-fd for
3268 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3269 Do blocking full-size writes, and reads under a timeout. Once both input
3270 channels are closed, exit the process.
3271
3272 Arguments:
3273 ct_ctx tls context
3274 buf space to use for buffering
3275 bufsiz size of buffer
3276 pfd pipe filedescriptor array; [0] is comms to proxied process
3277 timeout per-read timeout, seconds
3278 */
3279
3280 void
3281 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3282 int timeout)
3283 {
3284 fd_set rfds, efds;
3285 int max_fd = MAX(pfd[0], tls_out.active.sock) + 1;
3286 int rc, i;
3287
3288 close(pfd[1]);
3289 if ((rc = fork()))
3290 {
3291 DEBUG(D_transport) debug_printf("proxy-proc final-pid %d\n", rc);
3292 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3293 }
3294
3295 if (f.running_in_test_harness) millisleep(100); /* let parent debug out */
3296 set_process_info("proxying TLS connection for continued transport");
3297 FD_ZERO(&rfds);
3298 FD_SET(tls_out.active.sock, &rfds);
3299 FD_SET(pfd[0], &rfds);
3300
3301 for (int fd_bits = 3; fd_bits; )
3302 {
3303 time_t time_left = timeout;
3304 time_t time_start = time(NULL);
3305
3306 /* wait for data */
3307 efds = rfds;
3308 do
3309 {
3310 struct timeval tv = { time_left, 0 };
3311
3312 rc = select(max_fd,
3313 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
3314
3315 if (rc < 0 && errno == EINTR)
3316 if ((time_left -= time(NULL) - time_start) > 0) continue;
3317
3318 if (rc <= 0)
3319 {
3320 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3321 goto done;
3322 }
3323
3324 if (FD_ISSET(tls_out.active.sock, &efds) || FD_ISSET(pfd[0], &efds))
3325 {
3326 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3327 FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
3328 goto done;
3329 }
3330 }
3331 while (rc < 0 || !(FD_ISSET(tls_out.active.sock, &rfds) || FD_ISSET(pfd[0], &rfds)));
3332
3333 /* handle inbound data */
3334 if (FD_ISSET(tls_out.active.sock, &rfds))
3335 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0)
3336 {
3337 fd_bits &= ~1;
3338 FD_CLR(tls_out.active.sock, &rfds);
3339 shutdown(pfd[0], SHUT_WR);
3340 timeout = 5;
3341 }
3342 else
3343 {
3344 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3345 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3346 }
3347 else if (fd_bits & 1)
3348 FD_SET(tls_out.active.sock, &rfds);
3349
3350 /* handle outbound data */
3351 if (FD_ISSET(pfd[0], &rfds))
3352 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3353 {
3354 fd_bits = 0;
3355 tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3356 ct_ctx = NULL;
3357 }
3358 else
3359 {
3360 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3361 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3362 goto done;
3363 }
3364 else if (fd_bits & 2)
3365 FD_SET(pfd[0], &rfds);
3366 }
3367
3368 done:
3369 if (f.running_in_test_harness) millisleep(100); /* let logging complete */
3370 exim_exit(0, US"TLS proxy");
3371 }
3372 #endif
3373
3374
3375 /*************************************************
3376 * Deliver address list to given host *
3377 *************************************************/
3378
3379 /* If continue_hostname is not null, we get here only when continuing to
3380 deliver down an existing channel. The channel was passed as the standard
3381 input. TLS is never active on a passed channel; the previous process always
3382 closes it down before passing the connection on.
3383
3384 Otherwise, we have to make a connection to the remote host, and do the
3385 initial protocol exchange.
3386
3387 When running as an MUA wrapper, if the sender or any recipient is rejected,
3388 temporarily or permanently, we force failure for all recipients.
3389
3390 Arguments:
3391 addrlist chain of potential addresses to deliver; only those whose
3392 transport_return field is set to PENDING_DEFER are currently
3393 being processed; others should be skipped - they have either
3394 been delivered to an earlier host or IP address, or been
3395 failed by one of them.
3396 host host to deliver to
3397 host_af AF_INET or AF_INET6
3398 defport default TCP/IP port to use if host does not specify, in host
3399 byte order
3400 interface interface to bind to, or NULL
3401 tblock transport instance block
3402 message_defer set TRUE if yield is OK, but all addresses were deferred
3403 because of a non-recipient, non-host failure, that is, a
3404 4xx response to MAIL FROM, DATA, or ".". This is a defer
3405 that is specific to the message.
3406 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3407 a second attempt after TLS initialization fails
3408
3409 Returns: OK - the connection was made and the delivery attempted;
3410 the result for each address is in its data block.
3411 DEFER - the connection could not be made, or something failed
3412 while setting up the SMTP session, or there was a
3413 non-message-specific error, such as a timeout.
3414 ERROR - a filter command is specified for this transport,
3415 and there was a problem setting it up; OR helo_data
3416 or add_headers or authenticated_sender is specified
3417 for this transport, and the string failed to expand
3418 */
3419
3420 static int
3421 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3422 uschar *interface, transport_instance *tblock,
3423 BOOL *message_defer, BOOL suppress_tls)
3424 {
3425 smtp_transport_options_block * ob = SOB tblock->options_block;
3426 int yield = OK;
3427 int save_errno;
3428 int rc;
3429 struct timeval start_delivery_time;
3430
3431 BOOL pass_message = FALSE;
3432 uschar *message = NULL;
3433 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3434
3435 smtp_context sx;
3436
3437 gettimeofday(&start_delivery_time, NULL);
3438 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
3439 *message_defer = FALSE;
3440
3441 sx.addrlist = addrlist;
3442 sx.conn_args.host = host;
3443 sx.conn_args.host_af = host_af,
3444 sx.port = defport;
3445 sx.conn_args.interface = interface;
3446 sx.helo_data = NULL;
3447 sx.conn_args.tblock = tblock;
3448 sx.verify = FALSE;
3449 sx.sync_addr = sx.first_addr = addrlist;
3450
3451 /* Get the channel set up ready for a message (MAIL FROM being the next
3452 SMTP command to send */
3453
3454 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
3455 return rc;
3456
3457 /* If there is a filter command specified for this transport, we can now
3458 set it up. This cannot be done until the identify of the host is known. */
3459
3460 if (tblock->filter_command)
3461 {
3462 transport_filter_timeout = tblock->filter_timeout;
3463
3464 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3465 yield ERROR. */
3466
3467 if (!transport_set_up_command(&transport_filter_argv,
3468 tblock->filter_command, TRUE, DEFER, addrlist,
3469 string_sprintf("%.50s transport", tblock->name), NULL))
3470 {
3471 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3472 FALSE);
3473 yield = ERROR;
3474 goto SEND_QUIT;
3475 }
3476
3477 if ( transport_filter_argv
3478 && *transport_filter_argv
3479 && **transport_filter_argv
3480 && sx.peer_offered & OPTION_CHUNKING
3481 )
3482 {
3483 sx.peer_offered &= ~OPTION_CHUNKING;
3484 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3485 }
3486 }
3487
3488 /* For messages that have more than the maximum number of envelope recipients,
3489 we want to send several transactions down the same SMTP connection. (See
3490 comments in deliver.c as to how this reconciles, heuristically, with
3491 remote_max_parallel.) This optimization was added to Exim after the following
3492 code was already working. The simplest way to put it in without disturbing the
3493 code was to use a goto to jump back to this point when there is another
3494 transaction to handle. */
3495
3496 SEND_MESSAGE:
3497 sx.from_addr = return_path;
3498 sx.sync_addr = sx.first_addr;
3499 sx.ok = FALSE;
3500 sx.send_rset = TRUE;
3501 sx.completed_addr = FALSE;
3502
3503
3504 /* If we are a continued-connection-after-verify the MAIL and RCPT
3505 commands were already sent; do not re-send but do mark the addrs as
3506 having been accepted up to RCPT stage. A traditional cont-conn
3507 always has a sequence number greater than one. */
3508
3509 if (continue_hostname && continue_sequence == 1)
3510 {
3511 sx.peer_offered = smtp_peer_options;
3512 sx.pending_MAIL = FALSE;
3513 sx.ok = TRUE;
3514 sx.next_addr = NULL;
3515
3516 for (address_item * addr = addrlist; addr; addr = addr->next)
3517 addr->transport_return = PENDING_OK;
3518 }
3519 else
3520 {
3521 /* Initiate a message transfer. */
3522
3523 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
3524 {
3525 case 0: break;
3526 case -1: case -2: goto RESPONSE_FAILED;
3527 case -3: goto END_OFF;
3528 case -4: goto SEND_QUIT;
3529 default: goto SEND_FAILED;
3530 }
3531
3532 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3533 permanently or temporarily. We should have flushed and synced after the last
3534 RCPT. */
3535
3536 if (mua_wrapper)
3537 {
3538 address_item * a;
3539 unsigned cnt;
3540
3541 for (a = sx.first_addr, cnt = 0; a && cnt < sx.max_rcpt; a = a->next, cnt++)
3542 if (a->transport_return != PENDING_OK)
3543 {
3544 /*XXX could we find a better errno than 0 here? */
3545 set_errno_nohost(addrlist, 0, a->message, FAIL,
3546 testflag(a, af_pass_message));
3547 sx.ok = FALSE;
3548 break;
3549 }
3550 }
3551 }
3552
3553 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3554 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3555 have a good recipient buffered up if we are pipelining. We don't want to waste
3556 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3557 are pipelining. The responses are all handled by sync_responses().
3558 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3559 to send is. */
3560
3561 if ( !(sx.peer_offered & OPTION_CHUNKING)
3562 && (sx.ok || (pipelining_active && !mua_wrapper)))
3563 {
3564 int count = smtp_write_command(&sx, SCMD_FLUSH, "DATA\r\n");
3565
3566 if (count < 0) goto SEND_FAILED;
3567 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
3568 {
3569 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3570 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3571 break;
3572
3573 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3574 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3575 case 0: break; /* No 2xx or 5xx, but no probs */
3576
3577 case -1: goto END_OFF; /* Timeout on RCPT */
3578
3579 #ifdef EXPERIMENTAL_PIPE_CONNECT
3580 case -5: /* TLS first-read error */
3581 case -4: HDEBUG(D_transport)
3582 debug_printf("failed reaping pipelined cmd responses\n");
3583 #endif
3584 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3585 }
3586 pipelining_active = FALSE;
3587 data_command = string_copy(big_buffer); /* Save for later error message */
3588 }
3589
3590 /* If there were no good recipients (but otherwise there have been no
3591 problems), just set ok TRUE, since we have handled address-specific errors
3592 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3593 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3594 well as body. Set the appropriate timeout value to be used for each chunk.
3595 (Haven't been able to make it work using select() for writing yet.) */
3596
3597 if (!(sx.peer_offered & OPTION_CHUNKING) && !sx.ok)
3598 {
3599 /* Save the first address of the next batch. */
3600 sx.first_addr = sx.next_addr;
3601
3602 sx.ok = TRUE;
3603 }
3604 else
3605 {
3606 transport_ctx tctx = {
3607 .u = {.fd = sx.cctx.sock}, /*XXX will this need TLS info? */
3608 .tblock = tblock,
3609 .addr = addrlist,
3610 .check_string = US".",
3611 .escape_string = US"..", /* Escaping strings */
3612 .options =
3613 topt_use_crlf | topt_escape_headers
3614 | (tblock->body_only ? topt_no_headers : 0)
3615 | (tblock->headers_only ? topt_no_body : 0)
3616 | (tblock->return_path_add ? topt_add_return_path : 0)
3617 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3618 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3619 };
3620
3621 /* If using CHUNKING we need a callback from the generic transport
3622 support to us, for the sending of BDAT smtp commands and the reaping
3623 of responses. The callback needs a whole bunch of state so set up
3624 a transport-context structure to be passed around. */
3625
3626 if (sx.peer_offered & OPTION_CHUNKING)
3627 {
3628 tctx.check_string = tctx.escape_string = NULL;
3629 tctx.options |= topt_use_bdat;
3630 tctx.chunk_cb = smtp_chunk_cmd_callback;
3631 sx.pending_BDAT = FALSE;
3632 sx.good_RCPT = sx.ok;
3633 sx.cmd_count = 0;
3634 tctx.smtp_context = &sx;
3635 }
3636 else
3637 tctx.options |= topt_end_dot;
3638
3639 /* Save the first address of the next batch. */
3640 sx.first_addr = sx.next_addr;
3641
3642 /* Responses from CHUNKING commands go in buffer. Otherwise,
3643 there has not been a response. */
3644
3645 sx.buffer[0] = 0;
3646
3647 sigalrm_seen = FALSE;
3648 transport_write_timeout = ob->data_timeout;
3649 smtp_command = US"sending data block"; /* For error messages */
3650 DEBUG(D_transport|D_v)
3651 if (sx.peer_offered & OPTION_CHUNKING)
3652 debug_printf(" will write message using CHUNKING\n");
3653 else
3654 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3655 transport_count = 0;
3656
3657 #ifndef DISABLE_DKIM
3658 dkim_exim_sign_init();
3659 # ifdef EXPERIMENTAL_ARC
3660 {
3661 uschar * s = ob->arc_sign;
3662 if (s)
3663 {
3664 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
3665 {
3666 if (!f.expand_string_forcedfail)
3667 {
3668 message = US"failed to expand arc_sign";
3669 sx.ok = FALSE;
3670 goto SEND_FAILED;
3671 }
3672 }
3673 else if (*s)
3674 {
3675 /* Ask dkim code to hash the body for ARC */
3676 (void) arc_ams_setup_sign_bodyhash();
3677 ob->dkim.force_bodyhash = TRUE;
3678 }
3679 }
3680 }
3681 # endif
3682 sx.ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
3683 #else
3684 sx.ok = transport_write_message(&tctx, 0);
3685 #endif
3686
3687 /* transport_write_message() uses write() because it is called from other
3688 places to write to non-sockets. This means that under some OS (e.g. Solaris)
3689 it can exit with "Broken pipe" as its error. This really means that the
3690 socket got closed at the far end. */
3691
3692 transport_write_timeout = 0; /* for subsequent transports */
3693
3694 /* Failure can either be some kind of I/O disaster (including timeout),
3695 or the failure of a transport filter or the expansion of added headers.
3696 Or, when CHUNKING, it can be a protocol-detected failure. */
3697
3698 if (!sx.ok)
3699 if (message) goto SEND_FAILED;
3700 else goto RESPONSE_FAILED;
3701
3702 /* We used to send the terminating "." explicitly here, but because of
3703 buffering effects at both ends of TCP/IP connections, you don't gain
3704 anything by keeping it separate, so it might as well go in the final
3705 data buffer for efficiency. This is now done by setting the topt_end_dot
3706 flag above. */
3707
3708 smtp_command = US"end of data";
3709
3710 if (sx.peer_offered & OPTION_CHUNKING && sx.cmd_count > 1)
3711 {
3712 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
3713 switch(sync_responses(&sx, sx.cmd_count-1, 0))
3714 {
3715 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3716 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3717 break;
3718
3719 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3720 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3721 case 0: break; /* No 2xx or 5xx, but no probs */
3722
3723 case -1: goto END_OFF; /* Timeout on RCPT */
3724
3725 #ifdef EXPERIMENTAL_PIPE_CONNECT
3726 case -5: /* TLS first-read error */
3727 case -4: HDEBUG(D_transport)
3728 debug_printf("failed reaping pipelined cmd responses\n");
3729 #endif
3730 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3731 }
3732 }
3733
3734 #ifndef DISABLE_PRDR
3735 /* For PRDR we optionally get a partial-responses warning followed by the
3736 individual responses, before going on with the overall response. If we don't
3737 get the warning then deal with per non-PRDR. */
3738
3739 if(sx.prdr_active)
3740 {
3741 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '3', ob->final_timeout);
3742 if (!sx.ok && errno == 0) switch(sx.buffer[0])
3743 {
3744 case '2': sx.prdr_active = FALSE;
3745 sx.ok = TRUE;
3746 break;
3747 case '4': errno = ERRNO_DATA4XX;
3748 addrlist->more_errno |=
3749 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3750 break;
3751 }
3752 }
3753 else
3754 #endif
3755
3756 /* For non-PRDR SMTP, we now read a single response that applies to the
3757 whole message. If it is OK, then all the addresses have been delivered. */
3758
3759 if (!sx.lmtp)
3760 {
3761 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3762 ob->final_timeout);
3763 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
3764 {
3765 errno = ERRNO_DATA4XX;
3766 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3767 }
3768 }
3769
3770 /* For LMTP, we get back a response for every RCPT command that we sent;
3771 some may be accepted and some rejected. For those that get a response, their
3772 status is fixed; any that are accepted have been handed over, even if later
3773 responses crash - at least, that's how I read RFC 2033.
3774
3775 If all went well, mark the recipient addresses as completed, record which
3776 host/IPaddress they were delivered to, and cut out RSET when sending another
3777 message down the same channel. Write the completed addresses to the journal
3778 now so that they are recorded in case there is a crash of hardware or
3779 software before the spool gets updated. Also record the final SMTP
3780 confirmation if needed (for SMTP only). */
3781
3782 if (sx.ok)
3783 {
3784 int flag = '=';
3785 struct timeval delivery_time;
3786 int len;
3787 uschar * conf = NULL;
3788
3789 timesince(&delivery_time, &start_delivery_time);
3790 sx.send_rset = FALSE;
3791 pipelining_active = FALSE;
3792
3793 /* Set up confirmation if needed - applies only to SMTP */
3794
3795 if (
3796 #ifdef DISABLE_EVENT
3797 LOGGING(smtp_confirmation) &&
3798 #endif
3799 !sx.lmtp
3800 )
3801 {
3802 const uschar *s = string_printing(sx.buffer);
3803 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3804 conf = (s == sx.buffer)? US string_copy(s) : US s;
3805 }
3806
3807 /* Process all transported addresses - for LMTP or PRDR, read a status for
3808 each one. */
3809
3810 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3811 {
3812 if (addr->transport_return != PENDING_OK) continue;
3813
3814 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3815 remaining addresses. Otherwise, it's a return code for just the one
3816 address. For temporary errors, add a retry item for the address so that
3817 it doesn't get tried again too soon. */
3818
3819 #ifndef DISABLE_PRDR
3820 if (sx.lmtp || sx.prdr_active)
3821 #else
3822 if (sx.lmtp)
3823 #endif
3824 {
3825 if (!smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3826 ob->final_timeout))
3827 {
3828 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3829 addr->message = string_sprintf(
3830 #ifndef DISABLE_PRDR
3831 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3832 #else
3833 "LMTP error after %s: %s",
3834 #endif
3835 data_command, string_printing(sx.buffer));
3836 setflag(addr, af_pass_message); /* Allow message to go to user */
3837 if (sx.buffer[0] == '5')
3838 addr->transport_return = FAIL;
3839 else
3840 {
3841 errno = ERRNO_DATA4XX;
3842 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3843 addr->transport_return = DEFER;
3844 #ifndef DISABLE_PRDR
3845 if (!sx.prdr_active)
3846 #endif
3847 retry_add_item(addr, addr->address_retry_key, 0);
3848 }
3849 continue;
3850 }
3851 sx.completed_addr = TRUE; /* NOW we can set this flag */
3852 if (LOGGING(smtp_confirmation))
3853 {
3854 const uschar *s = string_printing(sx.buffer);
3855 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3856 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3857 }
3858 }
3859
3860 /* SMTP, or success return from LMTP for this address. Pass back the
3861 actual host that was used. */
3862
3863 addr->transport_return = OK;
3864 addr->more_errno = delivery_time.tv_sec;
3865 addr->delivery_usec = delivery_time.tv_usec;
3866 addr->host_used = host;
3867 addr->special_action = flag;
3868 addr->message = conf;
3869
3870 if (tcp_out_fastopen)
3871 {
3872 setflag(addr, af_tcp_fastopen_conn);
3873 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
3874 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
3875 }
3876 if (sx.pipelining_used) setflag(addr, af_pipelining);
3877 #ifdef EXPERIMENTAL_PIPE_CONNECT
3878 if (sx.early_pipe_active) setflag(addr, af_early_pipe);
3879 #endif
3880 #ifndef DISABLE_PRDR
3881 if (sx.prdr_active) setflag(addr, af_prdr_used);
3882 #endif
3883 if (sx.peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
3884 flag = '-';
3885
3886 #ifndef DISABLE_PRDR
3887 if (!sx.prdr_active)
3888 #endif
3889 {
3890 /* Update the journal. For homonymic addresses, use the base address plus
3891 the transport name. See lots of comments in deliver.c about the reasons
3892 for the complications when homonyms are involved. Just carry on after
3893 write error, as it may prove possible to update the spool file later. */
3894
3895 if (testflag(addr, af_homonym))
3896 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3897 else
3898 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3899
3900 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3901 len = Ustrlen(CS sx.buffer);
3902 if (write(journal_fd, sx.buffer, len) != len)
3903 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3904 "%s: %s", sx.buffer, strerror(errno));
3905 }
3906 }
3907
3908 #ifndef DISABLE_PRDR
3909 if (sx.prdr_active)
3910 {
3911 const uschar * overall_message;
3912
3913 /* PRDR - get the final, overall response. For any non-success
3914 upgrade all the address statuses. */
3915
3916 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3917 ob->final_timeout);
3918 if (!sx.ok)
3919 {
3920 if(errno == 0 && sx.buffer[0] == '4')
3921 {
3922 errno = ERRNO_DATA4XX;
3923 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3924 }
3925 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3926 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3927 addr->transport_return = PENDING_OK; /* allow set_errno action */
3928 goto RESPONSE_FAILED;
3929 }
3930
3931 /* Append the overall response to the individual PRDR response for logging
3932 and update the journal, or setup retry. */
3933
3934 overall_message = string_printing(sx.buffer);
3935 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3936 if (addr->transport_return == OK)
3937 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
3938
3939 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3940 if (addr->transport_return == OK)
3941 {
3942 if (testflag(addr, af_homonym))
3943 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3944 else
3945 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3946
3947 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3948 len = Ustrlen(CS sx.buffer);
3949 if (write(journal_fd, sx.buffer, len) != len)
3950 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3951 "%s: %s", sx.buffer, strerror(errno));
3952 }
3953 else if (addr->transport_return == DEFER)
3954 retry_add_item(addr, addr->address_retry_key, -2);
3955 }
3956 #endif
3957
3958 /* Ensure the journal file is pushed out to disk. */
3959
3960 if (EXIMfsync(journal_fd) < 0)
3961 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3962 strerror(errno));
3963 }
3964 }
3965
3966
3967 /* Handle general (not specific to one address) failures here. The value of ok
3968 is used to skip over this code on the falling through case. A timeout causes a
3969 deferral. Other errors may defer or fail according to the response code, and
3970 may set up a special errno value, e.g. after connection chopped, which is
3971 assumed if errno == 0 and there is no text in the buffer. If control reaches
3972 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3973 the problem is not related to this specific message. */
3974
3975 if (!sx.ok)
3976 {
3977 int code, set_rc;
3978 uschar * set_message;
3979
3980 RESPONSE_FAILED:
3981 {
3982 save_errno = errno;
3983 message = NULL;
3984 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3985 sx.buffer, &code, &message, &pass_message);
3986 goto FAILED;
3987 }
3988
3989 SEND_FAILED:
3990 {
3991 save_errno = errno;
3992 code = '4';
3993 message = string_sprintf("send() to %s [%s] failed: %s",
3994 host->name, host->address, message ? message : US strerror(save_errno));
3995 sx.send_quit = FALSE;
3996 goto FAILED;
3997 }
3998
3999 FAILED:
4000 {
4001 BOOL message_error;
4002
4003 sx.ok = FALSE; /* For when reached by GOTO */
4004 set_message = message;
4005
4006 /* We want to handle timeouts after MAIL or "." and loss of connection after
4007 "." specially. They can indicate a problem with the sender address or with
4008 the contents of the message rather than a real error on the connection. These
4009 cases are treated in the same way as a 4xx response. This next bit of code
4010 does the classification. */
4011
4012 switch(save_errno)
4013 {
4014 case 0:
4015 case ERRNO_MAIL4XX:
4016 case ERRNO_DATA4XX:
4017 message_error = TRUE;
4018 break;
4019
4020 case ETIMEDOUT:
4021 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4022 Ustrncmp(smtp_command,"end ",4) == 0;
4023 break;
4024
4025 case ERRNO_SMTPCLOSED:
4026 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4027 break;
4028
4029 default:
4030 message_error = FALSE;
4031 break;
4032 }
4033
4034 /* Handle the cases that are treated as message errors. These are:
4035
4036 (a) negative response or timeout after MAIL
4037 (b) negative response after DATA
4038 (c) negative response or timeout or dropped connection after "."
4039 (d) utf8 support required and not offered
4040
4041 It won't be a negative response or timeout after RCPT, as that is dealt
4042 with separately above. The action in all cases is to set an appropriate
4043 error code for all the addresses, but to leave yield set to OK because the
4044 host itself has not failed. Of course, it might in practice have failed
4045 when we've had a timeout, but if so, we'll discover that at the next
4046 delivery attempt. For a temporary error, set the message_defer flag, and
4047 write to the logs for information if this is not the last host. The error
4048 for the last host will be logged as part of the address's log line. */
4049
4050 if (message_error)
4051 {
4052 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4053
4054 /* If there's an errno, the message contains just the identity of
4055 the host. */
4056
4057 if (code == '5')
4058 set_rc = FAIL;
4059 else /* Anything other than 5 is treated as temporary */
4060 {
4061 set_rc = DEFER;
4062 if (save_errno > 0)
4063 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4064
4065 write_logs(host, message, sx.first_addr ? sx.first_addr->basic_errno : 0);
4066
4067 *message_defer = TRUE;
4068 }
4069 }
4070
4071 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4072 ".", or some other transportation error. We defer all addresses and yield
4073 DEFER, except for the case of failed add_headers expansion, or a transport
4074 filter failure, when the yield should be ERROR, to stop it trying other
4075 hosts. */
4076
4077 else
4078 {
4079 #ifdef EXPERIMENTAL_PIPE_CONNECT
4080 /* If we were early-pipelinng and the actual EHLO response did not match
4081 the cached value we assumed, we could have detected it and passed a
4082 custom errno through to here. It would be nice to RSET and retry right
4083 away, but to reliably do that we eould need an extra synch point before
4084 we committed to data and that would discard half the gained roundrips.
4085 Or we could summarily drop the TCP connection. but that is also ugly.
4086 Instead, we ignore the possibility (having freshened the cache) and rely
4087 on the server telling us with a nonmessage error if we have tried to
4088 do something it no longer supports. */
4089 #endif
4090 set_rc = DEFER;
4091 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4092 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4093 }
4094 }
4095
4096 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
4097 #ifdef EXPERIMENTAL_DSN_INFO
4098 , sx.smtp_greeting, sx.helo_response
4099 #endif
4100 );
4101 }
4102
4103
4104 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4105 SMTP session tidily. However, if there were too many addresses to send in one
4106 message (indicated by first_addr being non-NULL) we want to carry on with the
4107 rest of them. Also, it is desirable to send more than one message down the SMTP
4108 connection if there are several waiting, provided we haven't already sent so
4109 many as to hit the configured limit. The function transport_check_waiting looks
4110 for a waiting message and returns its id. Then transport_pass_socket tries to
4111 set up a continued delivery by passing the socket on to another process. The
4112 variable send_rset is FALSE if a message has just been successfully transferred.
4113
4114 If we are already sending down a continued channel, there may be further
4115 addresses not yet delivered that are aimed at the same host, but which have not
4116 been passed in this run of the transport. In this case, continue_more will be
4117 true, and all we should do is send RSET if necessary, and return, leaving the
4118 channel open.
4119
4120 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4121 do not want to continue with other messages down the same channel, because that
4122 can lead to looping between two or more messages, all with the same,
4123 temporarily failing address(es). [The retry information isn't updated yet, so
4124 new processes keep on trying.] We probably also don't want to try more of this
4125 message's addresses either.
4126
4127 If we have started a TLS session, we have to end it before passing the
4128 connection to a new process. However, not all servers can handle this (Exim
4129 can), so we do not pass such a connection on if the host matches
4130 hosts_nopass_tls. */
4131
4132 DEBUG(D_transport)
4133 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4134 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
4135 sx.send_rset, f.continue_more, yield, sx.first_addr ? "not " : "");
4136
4137 if (sx.completed_addr && sx.ok && sx.send_quit)
4138 {
4139 BOOL more;
4140 smtp_compare_t t_compare;
4141
4142 t_compare.tblock = tblock;
4143 t_compare.current_sender_address = sender_address;
4144
4145 if ( sx.first_addr != NULL
4146 || f.continue_more
4147 || (
4148 #ifndef DISABLE_TLS
4149 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4150 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4151 )
4152 &&
4153 #endif
4154 transport_check_waiting(tblock->name, host->name,
4155 tblock->connection_max_messages, new_message_id, &more,
4156 (oicf)smtp_are_same_identities, (void*)&t_compare)
4157 ) )
4158 {
4159 uschar *msg;
4160 BOOL pass_message;
4161
4162 if (sx.send_rset)
4163 if (! (sx.ok = smtp_write_command(&sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4164 {
4165 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
4166 host->address, strerror(errno));
4167 sx.send_quit = FALSE;
4168 }
4169 else if (! (sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer),
4170 '2', ob->command_timeout)))
4171 {
4172 int code;
4173 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
4174 &pass_message);
4175 if (!sx.send_quit)
4176 {
4177 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4178 host->name, host->address, msg);
4179 }
4180 }
4181
4182 /* Either RSET was not needed, or it succeeded */
4183
4184 if (sx.ok)
4185 {
4186 #ifndef DISABLE_TLS
4187 int pfd[2];
4188 #endif
4189 int socket_fd = sx.cctx.sock;
4190
4191
4192 if (sx.first_addr != NULL) /* More addresses still to be sent */
4193 { /* in this run of the transport */
4194 continue_sequence++; /* Causes * in logging */
4195 goto SEND_MESSAGE;
4196 }
4197
4198 /* Unless caller said it already has more messages listed for this host,
4199 pass the connection on to a new Exim process (below, the call to
4200 transport_pass_socket). If the caller has more ready, just return with
4201 the connection still open. */
4202
4203 #ifndef DISABLE_TLS
4204 if (tls_out.active.sock >= 0)
4205 if ( f.continue_more
4206 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4207 {
4208 /* Before passing the socket on, or returning to caller with it still
4209 open, we must shut down TLS. Not all MTAs allow for the continuation
4210 of the SMTP session when TLS is shut down. We test for this by sending
4211 a new EHLO. If we don't get a good response, we don't attempt to pass
4212 the socket on. */
4213
4214 tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4215 sx.cctx.tls_ctx = NULL;
4216 smtp_peer_options = smtp_peer_options_wrap;
4217 sx.ok = !sx.smtps
4218 && smtp_write_command(&sx, SCMD_FLUSH, "EHLO %s\r\n", sx.helo_data)
4219 >= 0
4220 && smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer),
4221 '2', ob->command_timeout);
4222
4223 if (sx.ok && f.continue_more)
4224 return yield; /* More addresses for another run */
4225 }
4226 else
4227 {
4228 /* Set up a pipe for proxying TLS for the new transport process */
4229
4230 smtp_peer_options |= OPTION_TLS;
4231 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4232 socket_fd = pfd[1];
4233 else
4234 set_errno(sx.first_addr, errno, US"internal allocation problem",
4235 DEFER, FALSE, host
4236 # ifdef EXPERIMENTAL_DSN_INFO
4237 , sx.smtp_greeting, sx.helo_response
4238 # endif
4239 );
4240 }
4241 else
4242 #endif
4243 if (f.continue_more)
4244 return yield; /* More addresses for another run */
4245
4246 /* If the socket is successfully passed, we mustn't send QUIT (or
4247 indeed anything!) from here. */
4248
4249 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4250 propagate it from the initial
4251 */
4252 if (sx.ok && transport_pass_socket(tblock->name, host->name,
4253 host->address, new_message_id, socket_fd))
4254 {
4255 sx.send_quit = FALSE;
4256
4257 /* We have passed the client socket to a fresh transport process.
4258 If TLS is still active, we need to proxy it for the transport we
4259 just passed the baton to. Fork a child to to do it, and return to
4260 get logging done asap. Which way to place the work makes assumptions
4261 about post-fork prioritisation which may not hold on all platforms. */
4262 #ifndef DISABLE_TLS
4263 if (tls_out.active.sock >= 0)
4264 {
4265 int pid = fork();
4266 if (pid == 0) /* child; fork again to disconnect totally */
4267 {
4268 if (f.running_in_test_harness) millisleep(100); /* let parent debug out */
4269 /* does not return */
4270 smtp_proxy_tls(sx.cctx.tls_ctx, sx.buffer, sizeof(sx.buffer), pfd,
4271 ob->command_timeout);
4272 }
4273
4274 if (pid > 0) /* parent */
4275 {
4276 DEBUG(D_transport) debug_printf("proxy-proc inter-pid %d\n", pid);
4277 close(pfd[0]);
4278 /* tidy the inter-proc to disconn the proxy proc */
4279 waitpid(pid, NULL, 0);
4280 tls_close(sx.cctx.tls_ctx, TLS_NO_SHUTDOWN);
4281 sx.cctx.tls_ctx = NULL;
4282 (void)close(sx.cctx.sock);
4283 sx.cctx.sock = -1;
4284 continue_transport = NULL;
4285 continue_hostname = NULL;
4286 return yield;
4287 }
4288 log_write(0, LOG_PANIC_DIE, "fork failed");
4289 }
4290 #endif
4291 }
4292 }
4293
4294 /* If RSET failed and there are addresses left, they get deferred. */
4295 else
4296 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
4297 #ifdef EXPERIMENTAL_DSN_INFO
4298 , sx.smtp_greeting, sx.helo_response
4299 #endif
4300 );
4301 }
4302 }
4303
4304 /* End off tidily with QUIT unless the connection has died or the socket has
4305 been passed to another process. There has been discussion on the net about what
4306 to do after sending QUIT. The wording of the RFC suggests that it is necessary
4307 to wait for a response, but on the other hand, there isn't anything one can do
4308 with an error response, other than log it. Exim used to do that. However,
4309 further discussion suggested that it is positively advantageous not to wait for
4310 the response, but to close the session immediately. This is supposed to move
4311 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
4312 load from the server. (Hosts that are both servers and clients may not see much
4313 difference, of course.) Further discussion indicated that this was safe to do
4314 on Unix systems which have decent implementations of TCP/IP that leave the
4315 connection around for a while (TIME_WAIT) after the application has gone away.
4316 This enables the response sent by the server to be properly ACKed rather than
4317 timed out, as can happen on broken TCP/IP implementations on other OS.
4318
4319 This change is being made on 31-Jul-98. After over a year of trouble-free
4320 operation, the old commented-out code was removed on 17-Sep-99. */
4321
4322 SEND_QUIT:
4323 #ifdef TCP_CORK
4324 (void) setsockopt(sx.cctx.sock, IPPROTO_TCP, TCP_CORK, US &on, sizeof(on));
4325 #endif
4326 if (sx.send_quit) (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4327
4328 END_OFF:
4329
4330 #ifndef DISABLE_TLS
4331 tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
4332 sx.cctx.tls_ctx = NULL;
4333 #endif
4334
4335 /* Close the socket, and return the appropriate value, first setting
4336 works because the NULL setting is passed back to the calling process, and
4337 remote_max_parallel is forced to 1 when delivering over an existing connection,
4338
4339 If all went well and continue_more is set, we shouldn't actually get here if
4340 there are further addresses, as the return above will be taken. However,
4341 writing RSET might have failed, or there may be other addresses whose hosts are
4342 specified in the transports, and therefore not visible at top level, in which
4343 case continue_more won't get set. */
4344
4345 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4346 if (sx.send_quit)
4347 {
4348 shutdown(sx.cctx.sock, SHUT_WR);
4349 millisleep(f.running_in_test_harness ? 200 : 20);
4350 if (fcntl(sx.cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4351 for (int i = 16; read(sx.cctx.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && i > 0;)
4352 i--; /* drain socket */
4353 }
4354 (void)close(sx.cctx.sock);
4355
4356 #ifndef DISABLE_EVENT
4357 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
4358 #endif
4359
4360 continue_transport = NULL;
4361 continue_hostname = NULL;
4362 return yield;
4363 }
4364
4365
4366
4367
4368 /*************************************************
4369 * Closedown entry point *
4370 *************************************************/
4371
4372 /* This function is called when exim is passed an open smtp channel
4373 from another incarnation, but the message which it has been asked
4374 to deliver no longer exists. The channel is on stdin.
4375
4376 We might do fancy things like looking for another message to send down
4377 the channel, but if the one we sought has gone, it has probably been
4378 delivered by some other process that itself will seek further messages,
4379 so just close down our connection.
4380
4381 Argument: pointer to the transport instance block
4382 Returns: nothing
4383 */
4384
4385 void
4386 smtp_transport_closedown(transport_instance *tblock)
4387 {
4388 smtp_transport_options_block * ob = SOB tblock->options_block;
4389 client_conn_ctx cctx;
4390 smtp_context sx;
4391 uschar buffer[256];
4392 uschar inbuffer[4096];
4393 uschar outbuffer[16];
4394
4395 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4396 cctx.sock = fileno(stdin);
4397 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4398
4399 sx.inblock.cctx = &cctx;
4400 sx.inblock.buffer = inbuffer;
4401 sx.inblock.buffersize = sizeof(inbuffer);
4402 sx.inblock.ptr = inbuffer;
4403 sx.inblock.ptrend = inbuffer;
4404
4405 sx.outblock.cctx = &cctx;
4406 sx.outblock.buffersize = sizeof(outbuffer);
4407 sx.outblock.buffer = outbuffer;
4408 sx.outblock.ptr = outbuffer;
4409 sx.outblock.cmd_count = 0;
4410 sx.outblock.authenticating = FALSE;
4411
4412 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4413 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
4414 (void)close(cctx.sock);
4415 }
4416
4417
4418
4419 /*************************************************
4420 * Prepare addresses for delivery *
4421 *************************************************/
4422
4423 /* This function is called to flush out error settings from previous delivery
4424 attempts to other hosts. It also records whether we got here via an MX record
4425 or not in the more_errno field of the address. We are interested only in
4426 addresses that are still marked DEFER - others may have got delivered to a
4427 previously considered IP address. Set their status to PENDING_DEFER to indicate
4428 which ones are relevant this time.
4429
4430 Arguments:
4431 addrlist the list of addresses
4432 host the host we are delivering to
4433
4434 Returns: the first address for this delivery
4435 */
4436
4437 static address_item *
4438 prepare_addresses(address_item *addrlist, host_item *host)
4439 {
4440 address_item *first_addr = NULL;
4441 for (address_item * addr = addrlist; addr; addr = addr->next)
4442 if (addr->transport_return == DEFER)
4443 {
4444 if (!first_addr) first_addr = addr;
4445 addr->transport_return = PENDING_DEFER;
4446 addr->basic_errno = 0;
4447 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
4448 addr->message = NULL;
4449 #ifndef DISABLE_TLS
4450 addr->cipher = NULL;
4451 addr->ourcert = NULL;
4452 addr->peercert = NULL;
4453 addr->peerdn = NULL;
4454 addr->ocsp = OCSP_NOT_REQ;
4455 #endif
4456 #ifdef EXPERIMENTAL_DSN_INFO
4457 addr->smtp_greeting = NULL;
4458 addr->helo_response = NULL;
4459 #endif
4460 }
4461 return first_addr;
4462 }
4463
4464
4465
4466 /*************************************************
4467 * Main entry point *
4468 *************************************************/
4469
4470 /* See local README for interface details. As this is a remote transport, it is
4471 given a chain of addresses to be delivered in one connection, if possible. It
4472 always returns TRUE, indicating that each address has its own independent
4473 status set, except if there is a setting up problem, in which case it returns
4474 FALSE. */
4475
4476 BOOL
4477 smtp_transport_entry(
4478 transport_instance *tblock, /* data for this instantiation */
4479 address_item *addrlist) /* addresses we are working on */
4480 {
4481 int defport;
4482 int hosts_defer = 0;
4483 int hosts_fail = 0;
4484 int hosts_looked_up = 0;
4485 int hosts_retry = 0;
4486 int hosts_serial = 0;
4487 int hosts_total = 0;
4488 int total_hosts_tried = 0;
4489 BOOL expired = TRUE;
4490 uschar *expanded_hosts = NULL;
4491 uschar *pistring;
4492 uschar *tid = string_sprintf("%s transport", tblock->name);
4493 smtp_transport_options_block *ob = SOB tblock->options_block;
4494 host_item *hostlist = addrlist->host_list;
4495 host_item *host = NULL;
4496
4497 DEBUG(D_transport)
4498 {
4499 debug_printf("%s transport entered\n", tblock->name);
4500 for (address_item * addr = addrlist; addr; addr = addr->next)
4501 debug_printf(" %s\n", addr->address);
4502 if (hostlist)
4503 {
4504 debug_printf("hostlist:\n");
4505 for (host_item * host = hostlist; host; host = host->next)
4506 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
4507 }
4508 if (continue_hostname)
4509 debug_printf("already connected to %s [%s] (on fd %d)\n",
4510 continue_hostname, continue_host_address,
4511 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
4512 }
4513
4514 /* Set the flag requesting that these hosts be added to the waiting
4515 database if the delivery fails temporarily or if we are running with
4516 queue_smtp or a 2-stage queue run. This gets unset for certain
4517 kinds of error, typically those that are specific to the message. */
4518
4519 update_waiting = TRUE;
4520
4521 /* If a host list is not defined for the addresses - they must all have the
4522 same one in order to be passed to a single transport - or if the transport has
4523 a host list with hosts_override set, use the host list supplied with the
4524 transport. It is an error for this not to exist. */
4525
4526 if (!hostlist || (ob->hosts_override && ob->hosts))
4527 {
4528 if (!ob->hosts)
4529 {
4530 addrlist->message = string_sprintf("%s transport called with no hosts set",
4531 tblock->name);
4532 addrlist->transport_return = PANIC;
4533 return FALSE; /* Only top address has status */
4534 }
4535
4536 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
4537 ob->hosts);
4538
4539 /* If the transport's host list contains no '$' characters, and we are not
4540 randomizing, it is fixed and therefore a chain of hosts can be built once
4541 and for all, and remembered for subsequent use by other calls to this
4542 transport. If, on the other hand, the host list does contain '$', or we are
4543 randomizing its order, we have to rebuild it each time. In the fixed case,
4544 as the hosts string will never be used again, it doesn't matter that we
4545 replace all the : characters with zeros. */
4546
4547 if (!ob->hostlist)
4548 {
4549 uschar *s = ob->hosts;
4550
4551 if (Ustrchr(s, '$') != NULL)
4552 {
4553 if (!(expanded_hosts = expand_string(s)))
4554 {
4555 addrlist->message = string_sprintf("failed to expand list of hosts "
4556 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
4557 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
4558 return FALSE; /* Only top address has status */
4559 }
4560 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
4561 "\"%s\"\n", s, expanded_hosts);
4562 s = expanded_hosts;
4563 }
4564 else
4565 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
4566
4567 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
4568
4569 /* Check that the expansion yielded something useful. */
4570 if (!hostlist)
4571 {
4572 addrlist->message =
4573 string_sprintf("%s transport has empty hosts setting", tblock->name);
4574 addrlist->transport_return = PANIC;
4575 return FALSE; /* Only top address has status */
4576 }
4577
4578 /* If there was no expansion of hosts, save the host list for
4579 next time. */
4580
4581 if (!expanded_hosts) ob->hostlist = hostlist;
4582 }
4583
4584 /* This is not the first time this transport has been run in this delivery;
4585 the host list was built previously. */
4586
4587 else
4588 hostlist = ob->hostlist;
4589 }
4590
4591 /* The host list was supplied with the address. If hosts_randomize is set, we
4592 must sort it into a random order if it did not come from MX records and has not
4593 already been randomized (but don't bother if continuing down an existing
4594 connection). */
4595
4596 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
4597 {
4598 host_item *newlist = NULL;
4599 while (hostlist)
4600 {
4601 host_item *h = hostlist;
4602 hostlist = hostlist->next;
4603
4604 h->sort_key = random_number(100);
4605
4606 if (!newlist)
4607 {
4608 h->next = NULL;
4609 newlist = h;
4610 }
4611 else if (h->sort_key < newlist->sort_key)
4612 {
4613 h->next = newlist;
4614 newlist = h;
4615 }
4616 else
4617 {
4618 host_item *hh = newlist;
4619 while (hh->next)
4620 {
4621 if (h->sort_key < hh->next->sort_key) break;
4622 hh = hh->next;
4623 }
4624 h->next = hh->next;
4625 hh->next = h;
4626 }
4627 }
4628
4629 hostlist = addrlist->host_list = newlist;
4630 }
4631
4632 /* Sort out the default port. */
4633
4634 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
4635
4636 /* For each host-plus-IP-address on the list:
4637
4638 . If this is a continued delivery and the host isn't the one with the
4639 current connection, skip.
4640
4641 . If the status is unusable (i.e. previously failed or retry checked), skip.
4642
4643 . If no IP address set, get the address, either by turning the name into
4644 an address, calling gethostbyname if gethostbyname is on, or by calling
4645 the DNS. The DNS may yield multiple addresses, in which case insert the
4646 extra ones into the list.
4647
4648 . Get the retry data if not previously obtained for this address and set the
4649 field which remembers the state of this address. Skip if the retry time is
4650 not reached. If not, remember whether retry data was found. The retry string
4651 contains both the name and the IP address.
4652
4653 . Scan the list of addresses and mark those whose status is DEFER as
4654 PENDING_DEFER. These are the only ones that will be processed in this cycle
4655 of the hosts loop.
4656
4657 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
4658 Some addresses may be successfully delivered, others may fail, and yet
4659 others may get temporary errors and so get marked DEFER.
4660
4661 . The return from the delivery attempt is OK if a connection was made and a
4662 valid SMTP dialogue was completed. Otherwise it is DEFER.
4663
4664 . If OK, add a "remove" retry item for this host/IPaddress, if any.
4665
4666 . If fail to connect, or other defer state, add a retry item.
4667
4668 . If there are any addresses whose status is still DEFER, carry on to the
4669 next host/IPaddress, unless we have tried the number of hosts given
4670 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
4671 there is some fancy logic for hosts_max_try that means its limit can be
4672 overstepped in some circumstances.
4673
4674 If we get to the end of the list, all hosts have deferred at least one address,
4675 or not reached their retry times. If delay_after_cutoff is unset, it requests a
4676 delivery attempt to those hosts whose last try was before the arrival time of
4677 the current message. To cope with this, we have to go round the loop a second
4678 time. After that, set the status and error data for any addresses that haven't
4679 had it set already. */
4680
4681 for (int cutoff_retry = 0;
4682 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
4683 cutoff_retry++)
4684 {
4685 host_item *nexthost = NULL;
4686 int unexpired_hosts_tried = 0;
4687 BOOL continue_host_tried = FALSE;
4688
4689 retry_non_continued:
4690 for (host = hostlist;
4691 host
4692 && unexpired_hosts_tried < ob->hosts_max_try
4693 && total_hosts_tried < ob->hosts_max_try_hardlimit;
4694 host = nexthost)
4695 {
4696 int rc;
4697 int host_af;
4698 BOOL host_is_expired = FALSE;
4699 BOOL message_defer = FALSE;
4700 BOOL some_deferred = FALSE;
4701 address_item *first_addr = NULL;
4702 uschar *interface = NULL;
4703 uschar *retry_host_key = NULL;
4704 uschar *retry_message_key = NULL;
4705 uschar *serialize_key = NULL;
4706
4707 /* Default next host is next host. :-) But this can vary if the
4708 hosts_max_try limit is hit (see below). It may also be reset if a host
4709 address is looked up here (in case the host was multihomed). */
4710
4711 nexthost = host->next;
4712
4713 /* If the address hasn't yet been obtained from the host name, look it up
4714 now, unless the host is already marked as unusable. If it is marked as
4715 unusable, it means that the router was unable to find its IP address (in
4716 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
4717 the lookup failed last time. We don't get this far if *all* MX records
4718 point to non-existent hosts; that is treated as a hard error.
4719
4720 We can just skip this host entirely. When the hosts came from the router,
4721 the address will timeout based on the other host(s); when the address is
4722 looked up below, there is an explicit retry record added.
4723
4724 Note that we mustn't skip unusable hosts if the address is not unset; they
4725 may be needed as expired hosts on the 2nd time round the cutoff loop. */
4726
4727 if (!host->address)
4728 {
4729 int new_port, flags;
4730
4731 if (host->status >= hstatus_unusable)
4732 {
4733 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
4734 host->name);
4735 continue;
4736 }
4737
4738 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
4739
4740 /* The host name is permitted to have an attached port. Find it, and
4741 strip it from the name. Just remember it for now. */
4742
4743 new_port = host_item_get_port(host);
4744
4745 /* Count hosts looked up */
4746
4747 hosts_looked_up++;
4748
4749 /* Find by name if so configured, or if it's an IP address. We don't
4750 just copy the IP address, because we need the test-for-local to happen. */
4751
4752 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
4753 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
4754 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
4755
4756 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
4757 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
4758 else
4759 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
4760 &ob->dnssec, /* domains for request/require */
4761 NULL, NULL);
4762
4763 /* Update the host (and any additional blocks, resulting from
4764 multihoming) with a host-specific port, if any. */
4765
4766 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
4767
4768 /* Failure to find the host at this time (usually DNS temporary failure)
4769 is really a kind of routing failure rather than a transport failure.
4770 Therefore we add a retry item of the routing kind, not to stop us trying
4771 to look this name up here again, but to ensure the address gets timed
4772 out if the failures go on long enough. A complete failure at this point
4773 commonly points to a configuration error, but the best action is still
4774 to carry on for the next host. */
4775
4776 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
4777 {
4778 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
4779 expired = FALSE;
4780 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
4781 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
4782 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
4783 host->status = hstatus_unusable;
4784
4785 for (address_item * addr = addrlist; addr; addr = addr->next)
4786 {
4787 if (addr->transport_return != DEFER) continue;
4788 addr->basic_errno = ERRNO_UNKNOWNHOST;
4789 addr->message = string_sprintf(
4790 rc == HOST_FIND_SECURITY
4791 ? "lookup of IP address for %s was insecure"
4792 : "failed to lookup IP address for %s",
4793 host->name);
4794 }
4795 continue;
4796 }
4797
4798 /* If the host is actually the local host, we may have a problem, or
4799 there may be some cunning configuration going on. In the problem case,
4800 log things and give up. The default transport status is already DEFER. */
4801
4802 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
4803 {
4804 for (address_item * addr = addrlist; addr; addr = addr->next)
4805 {
4806 addr->basic_errno = 0;
4807 addr->message = string_sprintf("%s transport found host %s to be "
4808 "local", tblock->name, host->name);
4809 }
4810 goto END_TRANSPORT;
4811 }
4812 } /* End of block for IP address lookup */
4813
4814 /* If this is a continued delivery, we are interested only in the host
4815 which matches the name of the existing open channel. The check is put
4816 here after the local host lookup, in case the name gets expanded as a
4817 result of the lookup. Set expired FALSE, to save the outer loop executing
4818 twice. */
4819
4820 if (continue_hostname)
4821 if ( Ustrcmp(continue_hostname, host->name) != 0
4822 || Ustrcmp(continue_host_address, host->address) != 0
4823 )
4824 {
4825 expired = FALSE;
4826 continue; /* With next host */
4827 }
4828 else
4829 continue_host_tried = TRUE;
4830
4831 /* Reset the default next host in case a multihomed host whose addresses
4832 are not looked up till just above added to the host list. */
4833
4834 nexthost = host->next;
4835
4836 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
4837 domain is in queue_smtp_domains, we don't actually want to attempt any
4838 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
4839 there is a lookup defer in queue_smtp_domains, proceed as if the domain
4840 were not in it. We don't want to hold up all SMTP deliveries! Except when
4841 doing a two-stage queue run, don't do this if forcing. */
4842
4843 if ((!f.deliver_force || f.queue_2stage) && (f.queue_smtp ||
4844 match_isinlist(addrlist->domain,
4845 (const uschar **)&queue_smtp_domains, 0,
4846 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
4847 {
4848 expired = FALSE;
4849 for (address_item * addr = addrlist; addr; addr = addr->next)
4850 if (addr->transport_return == DEFER)
4851 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
4852 continue; /* With next host */
4853 }
4854
4855 /* Count hosts being considered - purely for an intelligent comment
4856 if none are usable. */
4857
4858 hosts_total++;
4859
4860 /* Set $host and $host address now in case they are needed for the
4861 interface expansion or the serialize_hosts check; they remain set if an
4862 actual delivery happens. */
4863
4864 deliver_host = host->name;
4865 deliver_host_address = host->address;
4866 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
4867 : host->dnssec == DS_NO ? US"no"
4868 : US"";
4869
4870 /* Set up a string for adding to the retry key if the port number is not
4871 the standard SMTP port. A host may have its own port setting that overrides
4872 the default. */
4873
4874 pistring = string_sprintf(":%d", host->port == PORT_NONE
4875 ? defport : host->port);
4876 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
4877
4878 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
4879 string is set, even if constant (as different transports can have different
4880 constant settings), we must add it to the key that is used for retries,
4881 because connections to the same host from a different interface should be
4882 treated separately. */
4883
4884 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
4885 {
4886 uschar * s = ob->interface;
4887 if (s && *s)
4888 {
4889 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
4890 return FALSE;
4891 pistring = string_sprintf("%s/%s", pistring, interface);
4892 }
4893 }
4894
4895 /* The first time round the outer loop, check the status of the host by
4896 inspecting the retry data. The second time round, we are interested only
4897 in expired hosts that haven't been tried since this message arrived. */
4898
4899 if (cutoff_retry == 0)
4900 {
4901 BOOL incl_ip;
4902 /* Ensure the status of the address is set by checking retry data if
4903 necessary. There may be host-specific retry data (applicable to all
4904 messages) and also data for retries of a specific message at this host.
4905 If either of these retry records are actually read, the keys used are
4906 returned to save recomputing them later. */
4907
4908 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4909 US"retry_include_ip_address", ob->retry_include_ip_address,
4910 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4911 continue; /* with next host */
4912
4913 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4914 incl_ip, &retry_host_key, &retry_message_key);
4915
4916 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4917 host->address ? host->address : US"", pistring,
4918 host->status == hstatus_usable ? "usable"
4919 : host->status == hstatus_unusable ? "unusable"
4920 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
4921
4922 /* Skip this address if not usable at this time, noting if it wasn't
4923 actually expired, both locally and in the address. */
4924
4925 switch (host->status)
4926 {
4927 case hstatus_unusable:
4928 expired = FALSE;
4929 setflag(addrlist, af_retry_skipped);
4930 /* Fall through */
4931
4932 case hstatus_unusable_expired:
4933 switch (host->why)
4934 {
4935 case hwhy_retry: hosts_retry++; break;
4936 case hwhy_failed: hosts_fail++; break;
4937 case hwhy_insecure:
4938 case hwhy_deferred: hosts_defer++; break;
4939 }
4940
4941 /* If there was a retry message key, implying that previously there
4942 was a message-specific defer, we don't want to update the list of
4943 messages waiting for these hosts. */
4944
4945 if (retry_message_key) update_waiting = FALSE;
4946 continue; /* With the next host or IP address */
4947 }
4948 }
4949
4950 /* Second time round the loop: if the address is set but expired, and
4951 the message is newer than the last try, let it through. */
4952
4953 else
4954 {
4955 if ( !host->address
4956 || host->status != hstatus_unusable_expired
4957 || host->last_try > received_time.tv_sec)
4958 continue;
4959 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4960 host->name, host->address, pistring);
4961 host_is_expired = TRUE;
4962 }
4963
4964 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4965 it remains TRUE only if all hosts are expired and none are actually tried.
4966 */
4967
4968 expired = FALSE;
4969
4970 /* If this host is listed as one to which access must be serialized,
4971 see if another Exim process has a connection to it, and if so, skip
4972 this host. If not, update the database to record our connection to it
4973 and remember this for later deletion. Do not do any of this if we are
4974 sending the message down a pre-existing connection. */
4975
4976 if ( !continue_hostname
4977 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
4978 {
4979 serialize_key = string_sprintf("host-serialize-%s", host->name);
4980 if (!enq_start(serialize_key, 1))
4981 {
4982 DEBUG(D_transport)
4983 debug_printf("skipping host %s because another Exim process "
4984 "is connected to it\n", host->name);
4985 hosts_serial++;
4986 continue;
4987 }
4988 }
4989
4990 /* OK, we have an IP address that is not waiting for its retry time to
4991 arrive (it might be expired) OR (second time round the loop) we have an
4992 expired host that hasn't been tried since the message arrived. Have a go
4993 at delivering the message to it. First prepare the addresses by flushing
4994 out the result of previous attempts, and finding the first address that
4995 is still to be delivered. */
4996
4997 first_addr = prepare_addresses(addrlist, host);
4998
4999 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5000 message_id, host->name, host->address, addrlist->address,
5001 addrlist->next ? ", ..." : "");
5002
5003 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5004 message_id, host->name, host->address, pistring, addrlist->address,
5005 addrlist->next ? ", ..." : "");
5006
5007 /* This is not for real; don't do the delivery. If there are
5008 any remaining hosts, list them. */
5009
5010 if (f.dont_deliver)
5011 {
5012 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
5013 for (address_item * addr = addrlist; addr; addr = addr->next)
5014 {
5015 addr->host_used = host;
5016 addr->special_action = '*';
5017 addr->message = US"delivery bypassed by -N option";
5018 }
5019 DEBUG(D_transport)
5020 {
5021 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5022 "*** host and remaining hosts:\n", tblock->name);
5023 for (host_item * host2 = host; host2; host2 = host2->next)
5024 debug_printf(" %s [%s]\n", host2->name,
5025 host2->address ? host2->address : US"unset");
5026 }
5027 rc = OK;
5028 }
5029
5030 /* This is for real. If the host is expired, we don't count it for
5031 hosts_max_retry. This ensures that all hosts must expire before an address
5032 is timed out, unless hosts_max_try_hardlimit (which protects against
5033 lunatic DNS configurations) is reached.
5034
5035 If the host is not expired and we are about to hit the hosts_max_retry
5036 limit, check to see if there is a subsequent hosts with a different MX
5037 value. If so, make that the next host, and don't count this one. This is a
5038 heuristic to make sure that different MXs do get tried. With a normal kind
5039 of retry rule, they would get tried anyway when the earlier hosts were
5040 delayed, but if the domain has a "retry every time" type of rule - as is
5041 often used for the the very large ISPs, that won't happen. */
5042
5043 else
5044 {
5045 host_item * thost;
5046 /* Make a copy of the host if it is local to this invocation
5047 of the transport. */
5048
5049 if (expanded_hosts)
5050 {
5051 thost = store_get(sizeof(host_item));
5052 *thost = *host;
5053 thost->name = string_copy(host->name);
5054 thost->address = string_copy(host->address);
5055 }
5056 else
5057 thost = host;
5058
5059 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5060 {
5061 DEBUG(D_transport)
5062 debug_printf("hosts_max_try limit reached with this host\n");
5063 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5064 {
5065 nexthost = h;
5066 unexpired_hosts_tried--;
5067 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5068 "and will be tried\n");
5069 break;
5070 }
5071 }
5072
5073 /* Attempt the delivery. */
5074
5075 total_hosts_tried++;
5076 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5077 &message_defer, FALSE);
5078
5079 /* Yield is one of:
5080 OK => connection made, each address contains its result;
5081 message_defer is set for message-specific defers (when all
5082 recipients are marked defer)
5083 DEFER => there was a non-message-specific delivery problem;
5084 ERROR => there was a problem setting up the arguments for a filter,
5085 or there was a problem with expanding added headers
5086 */
5087
5088 /* If the result is not OK, there was a non-message-specific problem.
5089 If the result is DEFER, we need to write to the logs saying what happened
5090 for this particular host, except in the case of authentication and TLS
5091 failures, where the log has already been written. If all hosts defer a
5092 general message is written at the end. */
5093
5094 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5095 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5096 write_logs(host, first_addr->message, first_addr->basic_errno);
5097
5098 #ifndef DISABLE_EVENT
5099 if (rc == DEFER)
5100 deferred_event_raise(first_addr, host);
5101 #endif
5102
5103 /* If STARTTLS was accepted, but there was a failure in setting up the
5104 TLS session (usually a certificate screwup), and the host is not in
5105 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5106 TLS forcibly turned off. We have to start from scratch with a new SMTP
5107 connection. That's why the retry is done from here, not from within
5108 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5109 session, so the in-clear transmission after those errors, if permitted,
5110 happens inside smtp_deliver().] */
5111
5112 #ifndef DISABLE_TLS
5113 if ( rc == DEFER
5114 && first_addr->basic_errno == ERRNO_TLSFAILURE
5115 && ob->tls_tempfail_tryclear
5116 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5117 )
5118 {
5119 log_write(0, LOG_MAIN,
5120 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5121 first_addr->message, host->name, host->address);
5122 first_addr = prepare_addresses(addrlist, host);
5123 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5124 &message_defer, TRUE);
5125 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5126 write_logs(host, first_addr->message, first_addr->basic_errno);
5127 # ifndef DISABLE_EVENT
5128 if (rc == DEFER)
5129 deferred_event_raise(first_addr, host);
5130 # endif
5131 }
5132 #endif /*DISABLE_TLS*/
5133 }
5134
5135 /* Delivery attempt finished */
5136
5137 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5138 message_id, host->name, host->address, pistring, addrlist->address,
5139 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5140
5141 /* Release serialization if set up */
5142
5143 if (serialize_key) enq_end(serialize_key);
5144
5145 /* If the result is DEFER, or if a host retry record is known to exist, we
5146 need to add an item to the retry chain for updating the retry database
5147 at the end of delivery. We only need to add the item to the top address,
5148 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5149 for any other delivery attempts using the same address. (It is copied into
5150 the unusable tree at the outer level, so even if different address blocks
5151 contain the same address, it still won't get tried again.) */
5152
5153 if (rc == DEFER || retry_host_key)
5154 {
5155 int delete_flag = rc != DEFER ? rf_delete : 0;
5156 if (!retry_host_key)
5157 {
5158 BOOL incl_ip;
5159 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5160 US"retry_include_ip_address", ob->retry_include_ip_address,
5161 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5162 incl_ip = TRUE; /* error; use most-specific retry record */
5163
5164 retry_host_key = incl_ip
5165 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5166 : string_sprintf("T:%S%s", host->name, pistring);
5167 }
5168
5169 /* If a delivery of another message over an existing SMTP connection
5170 yields DEFER, we do NOT set up retry data for the host. This covers the
5171 case when there are delays in routing the addresses in the second message
5172 that are so long that the server times out. This is alleviated by not
5173 routing addresses that previously had routing defers when handling an
5174 existing connection, but even so, this case may occur (e.g. if a
5175 previously happily routed address starts giving routing defers). If the
5176 host is genuinely down, another non-continued message delivery will
5177 notice it soon enough. */
5178
5179 if (delete_flag != 0 || !continue_hostname)
5180 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5181
5182 /* We may have tried an expired host, if its retry time has come; ensure
5183 the status reflects the expiry for the benefit of any other addresses. */
5184
5185 if (rc == DEFER)
5186 {
5187 host->status = host_is_expired
5188 ? hstatus_unusable_expired : hstatus_unusable;
5189 host->why = hwhy_deferred;
5190 }
5191 }
5192
5193 /* If message_defer is set (host was OK, but every recipient got deferred
5194 because of some message-specific problem), or if that had happened
5195 previously so that a message retry key exists, add an appropriate item
5196 to the retry chain. Note that if there was a message defer but now there is
5197 a host defer, the message defer record gets deleted. That seems perfectly
5198 reasonable. Also, stop the message from being remembered as waiting
5199 for specific hosts. */
5200
5201 if (message_defer || retry_message_key)
5202 {
5203 int delete_flag = message_defer ? 0 : rf_delete;
5204 if (!retry_message_key)
5205 {
5206 BOOL incl_ip;
5207 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5208 US"retry_include_ip_address", ob->retry_include_ip_address,
5209 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5210 incl_ip = TRUE; /* error; use most-specific retry record */
5211
5212 retry_message_key = incl_ip
5213 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5214 message_id)
5215 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5216 }
5217 retry_add_item(addrlist, retry_message_key,
5218 rf_message | rf_host | delete_flag);
5219 update_waiting = FALSE;
5220 }
5221
5222 /* Any return other than DEFER (that is, OK or ERROR) means that the
5223 addresses have got their final statuses filled in for this host. In the OK
5224 case, see if any of them are deferred. */
5225
5226 if (rc == OK)
5227 for (address_item * addr = addrlist; addr; addr = addr->next)
5228 if (addr->transport_return == DEFER)
5229 {
5230 some_deferred = TRUE;
5231 break;
5232 }
5233
5234 /* If no addresses deferred or the result was ERROR, return. We do this for
5235 ERROR because a failing filter set-up or add_headers expansion is likely to
5236 fail for any host we try. */
5237
5238 if (rc == ERROR || (rc == OK && !some_deferred))
5239 {
5240 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5241 return TRUE; /* Each address has its status */
5242 }
5243
5244 /* If the result was DEFER or some individual addresses deferred, let
5245 the loop run to try other hosts with the deferred addresses, except for the
5246 case when we were trying to deliver down an existing channel and failed.
5247 Don't try any other hosts in this case. */
5248
5249 if (continue_hostname) break;
5250
5251 /* If the whole delivery, or some individual addresses, were deferred and
5252 there are more hosts that could be tried, do not count this host towards
5253 the hosts_max_try limit if the age of the message is greater than the
5254 maximum retry time for this host. This means we may try try all hosts,
5255 ignoring the limit, when messages have been around for some time. This is
5256 important because if we don't try all hosts, the address will never time
5257 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5258
5259 if ((rc == DEFER || some_deferred) && nexthost)
5260 {
5261 BOOL timedout;
5262 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5263
5264 if (retry && retry->rules)
5265 {
5266 retry_rule *last_rule;
5267 for (last_rule = retry->rules;
5268 last_rule->next;
5269 last_rule = last_rule->next);
5270 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5271 }
5272 else timedout = TRUE; /* No rule => timed out */
5273
5274 if (timedout)
5275 {
5276 unexpired_hosts_tried--;
5277 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5278 "hosts_max_try (message older than host's retry time)\n");
5279 }
5280 }
5281
5282 DEBUG(D_transport)
5283 {
5284 if (unexpired_hosts_tried >= ob->hosts_max_try)
5285 debug_printf("reached transport hosts_max_try limit %d\n",
5286 ob->hosts_max_try);
5287 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5288 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5289 ob->hosts_max_try_hardlimit);
5290 }
5291
5292 if (f.running_in_test_harness) millisleep(500); /* let server debug out */
5293 } /* End of loop for trying multiple hosts. */
5294
5295 /* If we failed to find a matching host in the list, for an already-open
5296 connection, just close it and start over with the list. This can happen
5297 for routing that changes from run to run, or big multi-IP sites with
5298 round-robin DNS. */
5299
5300 if (continue_hostname && !continue_host_tried)
5301 {
5302 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5303
5304 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5305 #ifndef DISABLE_TLS
5306 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5307 transport */
5308 /*XXX doublecheck that! */
5309
5310 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5311 {
5312 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5313 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5314 cutthrough.cctx.tls_ctx = NULL;
5315 cutthrough.is_tls = FALSE;
5316 }
5317 else
5318 #else
5319 (void) write(fd, US"QUIT\r\n", 6);
5320 #endif
5321 (void) close(fd);
5322 cutthrough.cctx.sock = -1;
5323 continue_hostname = NULL;
5324 goto retry_non_continued;
5325 }
5326
5327 /* This is the end of the loop that repeats iff expired is TRUE and
5328 ob->delay_after_cutoff is FALSE. The second time round we will
5329 try those hosts that haven't been tried since the message arrived. */
5330
5331 DEBUG(D_transport)
5332 {
5333 debug_printf("all IP addresses skipped or deferred at least one address\n");
5334 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5335 debug_printf("retrying IP addresses not tried since message arrived\n");
5336 }
5337 }
5338
5339
5340 /* Get here if all IP addresses are skipped or defer at least one address. In
5341 MUA wrapper mode, this will happen only for connection or other non-message-
5342 specific failures. Force the delivery status for all addresses to FAIL. */
5343
5344 if (mua_wrapper)
5345 {
5346 for (address_item * addr = addrlist; addr; addr = addr->next)
5347 addr->transport_return = FAIL;
5348 goto END_TRANSPORT;
5349 }
5350
5351 /* In the normal, non-wrapper case, add a standard message to each deferred
5352 address if there hasn't been an error, that is, if it hasn't actually been
5353 tried this time. The variable "expired" will be FALSE if any deliveries were
5354 actually tried, or if there was at least one host that was not expired. That
5355 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
5356 a delivery has been tried, an error code will be set, and the failing of the
5357 message is handled by the retry code later.
5358
5359 If queue_smtp is set, or this transport was called to send a subsequent message
5360 down an existing TCP/IP connection, and something caused the host not to be
5361 found, we end up here, but can detect these cases and handle them specially. */
5362
5363 for (address_item * addr = addrlist; addr; addr = addr->next)
5364 {
5365 /* If host is not NULL, it means that we stopped processing the host list
5366 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
5367 means we need to behave as if some hosts were skipped because their retry
5368 time had not come. Specifically, this prevents the address from timing out.
5369 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
5370 hosts were tried. */
5371
5372 if (host)
5373 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5374 {
5375 DEBUG(D_transport)
5376 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
5377 "hosts were tried\n");
5378 }
5379 else
5380 {
5381 DEBUG(D_transport)
5382 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
5383 setflag(addr, af_retry_skipped);
5384 }
5385
5386 if (f.queue_smtp) /* no deliveries attempted */
5387 {
5388 addr->transport_return = DEFER;
5389 addr->basic_errno = 0;
5390 addr->message = US"SMTP delivery explicitly queued";
5391 }
5392
5393 else if ( addr->transport_return == DEFER
5394 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
5395 && !addr->message
5396 )
5397 {
5398 addr->basic_errno = ERRNO_HRETRY;
5399 if (continue_hostname)
5400 addr->message = US"no host found for existing SMTP connection";
5401 else if (expired)
5402 {
5403 setflag(addr, af_pass_message); /* This is not a security risk */
5404 addr->message = string_sprintf(
5405 "all hosts%s have been failing for a long time %s",
5406 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
5407 ob->delay_after_cutoff
5408 ? US"(and retry time not reached)"
5409 : US"and were last tried after this message arrived");
5410
5411 /* If we are already using fallback hosts, or there are no fallback hosts
5412 defined, convert the result to FAIL to cause a bounce. */
5413
5414 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
5415 addr->transport_return = FAIL;
5416 }
5417 else
5418 {
5419 const char * s;
5420 if (hosts_retry == hosts_total)
5421 s = "retry time not reached for any host%s";
5422 else if (hosts_fail == hosts_total)
5423 s = "all host address lookups%s failed permanently";
5424 else if (hosts_defer == hosts_total)
5425 s = "all host address lookups%s failed temporarily";
5426 else if (hosts_serial == hosts_total)
5427 s = "connection limit reached for all hosts%s";
5428 else if (hosts_fail+hosts_defer == hosts_total)
5429 s = "all host address lookups%s failed";
5430 else
5431 s = "some host address lookups failed and retry time "
5432 "not reached for other hosts or connection limit reached%s";
5433
5434 addr->message = string_sprintf(s,
5435 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
5436 }
5437 }
5438 }
5439
5440 /* Update the database which keeps information about which messages are waiting
5441 for which hosts to become available. For some message-specific errors, the
5442 update_waiting flag is turned off because we don't want follow-on deliveries in
5443 those cases. If this transport instance is explicitly limited to one message
5444 per connection then follow-on deliveries are not possible and there's no need
5445 to create/update the per-transport wait-<transport_name> database. */
5446
5447 if (update_waiting && tblock->connection_max_messages != 1)
5448 transport_update_waiting(hostlist, tblock->name);
5449
5450 END_TRANSPORT:
5451
5452 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5453
5454 return TRUE; /* Each address has its status */
5455 }
5456
5457 #endif /*!MACRO_PREDEF*/
5458 /* vi: aw ai sw=2
5459 */
5460 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.