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[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11
12 /* Options specific to the smtp transport. This transport also supports LMTP
13 over TCP/IP. The options must be in alphabetic order (note that "_" comes
14 before the lower case letters). Some live in the transport_instance block so as
15 to be publicly visible; these are flagged with opt_public. */
16
17 optionlist smtp_transport_options[] = {
18 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
19 (void *)offsetof(transport_instance, expand_multi_domain) },
20 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
21 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
22
23 { "address_retry_include_sender", opt_bool,
24 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
25 { "allow_localhost", opt_bool,
26 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
27 #ifdef EXPERIMENTAL_ARC
28 { "arc_sign", opt_stringptr,
29 (void *)offsetof(smtp_transport_options_block, arc_sign) },
30 #endif
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 # ifdef SUPPORT_DANE
42 { "dane_require_tls_ciphers", opt_stringptr,
43 (void *)offsetof(smtp_transport_options_block, dane_require_tls_ciphers) },
44 # endif
45 { "data_timeout", opt_time,
46 (void *)offsetof(smtp_transport_options_block, data_timeout) },
47 { "delay_after_cutoff", opt_bool,
48 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
49 #ifndef DISABLE_DKIM
50 { "dkim_canon", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
52 { "dkim_domain", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
54 { "dkim_hash", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_hash) },
56 { "dkim_identity", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_identity) },
58 { "dkim_private_key", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
60 { "dkim_selector", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
62 { "dkim_sign_headers", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
64 { "dkim_strict", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
66 { "dkim_timestamps", opt_stringptr,
67 (void *)offsetof(smtp_transport_options_block, dkim.dkim_timestamps) },
68 #endif
69 { "dns_qualify_single", opt_bool,
70 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
71 { "dns_search_parents", opt_bool,
72 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
73 { "dnssec_request_domains", opt_stringptr,
74 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
75 { "dnssec_require_domains", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
77 { "dscp", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, dscp) },
79 { "fallback_hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
81 { "final_timeout", opt_time,
82 (void *)offsetof(smtp_transport_options_block, final_timeout) },
83 { "gethostbyname", opt_bool,
84 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
85 { "helo_data", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, helo_data) },
87 { "hosts", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts) },
89 { "hosts_avoid_esmtp", opt_stringptr,
90 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
91 { "hosts_avoid_pipelining", opt_stringptr,
92 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
93 #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 ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
594 s = string_printing(buffer);
595 while (isspace(*s)) s++;
596 *message = *s == 0
597 ? string_sprintf("Malformed SMTP reply (an empty line) "
598 "in response to %s%s", pl, smtp_command)
599 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
600 pl, smtp_command, s);
601 return FALSE;
602
603 case ERRNO_TLSFAILURE: /* Handle bad first read; can happen with
604 GnuTLS and TLS1.3 */
605 *message = US"bad first read from TLS conn";
606 return TRUE;
607
608 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
609 can't send QUIT as we mustn't end the DATA. */
610 *message = string_sprintf("transport filter process failed (%d)%s",
611 more_errno,
612 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
613 return FALSE;
614
615 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
616 can't send QUIT as we mustn't end the DATA. */
617 *message =
618 string_sprintf("failed to expand headers_add or headers_remove: %s",
619 expand_string_message);
620 return FALSE;
621
622 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
623 *message = string_sprintf("failed to write a data block");
624 return FALSE;
625
626 #ifdef SUPPORT_I18N
627 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
628 *message = US"utf8 support required but not offered for forwarding";
629 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
630 return TRUE;
631 #endif
632 }
633
634 /* Handle error responses from the remote mailer. */
635
636 if (buffer[0] != 0)
637 {
638 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
639 "%s", pl, smtp_command, s = string_printing(buffer));
640 *pass_message = TRUE;
641 *yield = buffer[0];
642 return TRUE;
643 }
644
645 /* No data was read. If there is no errno, this must be the EOF (i.e.
646 connection closed) case, which causes deferral. An explicit connection reset
647 error has the same effect. Otherwise, put the host's identity in the message,
648 leaving the errno value to be interpreted as well. In all cases, we have to
649 assume the connection is now dead. */
650
651 if (*errno_value == 0 || *errno_value == ECONNRESET)
652 {
653 *errno_value = ERRNO_SMTPCLOSED;
654 *message = US string_sprintf("Remote host closed connection "
655 "in response to %s%s", pl, smtp_command);
656 }
657 else
658 *message = US string_sprintf("%s [%s]", host->name, host->address);
659
660 return FALSE;
661 }
662
663
664
665 /*************************************************
666 * Write error message to logs *
667 *************************************************/
668
669 /* This writes to the main log and to the message log.
670
671 Arguments:
672 host the current host
673 detail the current message (addr_item->message)
674 basic_errno the errno (addr_item->basic_errno)
675
676 Returns: nothing
677 */
678
679 static void
680 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
681 {
682 gstring * message = LOGGING(outgoing_port)
683 ? string_fmt_append(NULL, "H=%s [%s]:%d", host->name, host->address,
684 host->port == PORT_NONE ? 25 : host->port)
685 : string_fmt_append(NULL, "H=%s [%s]", host->name, host->address);
686
687 if (suffix)
688 {
689 message = string_fmt_append(message, ": %s", suffix);
690 if (basic_errno > 0)
691 message = string_fmt_append(message, ": %s", strerror(basic_errno));
692 }
693 else
694 message = string_fmt_append(message, " %s", exim_errstr(basic_errno));
695
696 log_write(0, LOG_MAIN, "%s", string_from_gstring(message));
697 deliver_msglog("%s %s\n", tod_stamp(tod_log), message->s);
698 }
699
700 static void
701 msglog_line(host_item * host, uschar * message)
702 {
703 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
704 host->name, host->address, message);
705 }
706
707
708
709 #ifndef DISABLE_EVENT
710 /*************************************************
711 * Post-defer action *
712 *************************************************/
713
714 /* This expands an arbitrary per-transport string.
715 It might, for example, be used to write to the database log.
716
717 Arguments:
718 addr the address item containing error information
719 host the current host
720
721 Returns: nothing
722 */
723
724 static void
725 deferred_event_raise(address_item *addr, host_item *host)
726 {
727 uschar * action = addr->transport->event_action;
728 const uschar * save_domain;
729 uschar * save_local;
730
731 if (!action)
732 return;
733
734 save_domain = deliver_domain;
735 save_local = deliver_localpart;
736
737 /*XXX would ip & port already be set up? */
738 deliver_host_address = string_copy(host->address);
739 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
740 event_defer_errno = addr->basic_errno;
741
742 router_name = addr->router->name;
743 transport_name = addr->transport->name;
744 deliver_domain = addr->domain;
745 deliver_localpart = addr->local_part;
746
747 (void) event_raise(action, US"msg:host:defer",
748 addr->message
749 ? addr->basic_errno > 0
750 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
751 : string_copy(addr->message)
752 : addr->basic_errno > 0
753 ? string_copy(US strerror(addr->basic_errno))
754 : NULL);
755
756 deliver_localpart = save_local;
757 deliver_domain = save_domain;
758 router_name = transport_name = NULL;
759 }
760 #endif
761
762 /*************************************************
763 * Reap SMTP specific responses *
764 *************************************************/
765 static int
766 smtp_discard_responses(smtp_context * sx, smtp_transport_options_block * ob,
767 int count)
768 {
769 uschar flushbuffer[4096];
770
771 while (count-- > 0)
772 {
773 if (!smtp_read_response(sx, flushbuffer, sizeof(flushbuffer),
774 '2', ob->command_timeout)
775 && (errno != 0 || flushbuffer[0] == 0))
776 break;
777 }
778 return count;
779 }
780
781
782 /* Return boolean success */
783
784 static BOOL
785 smtp_reap_banner(smtp_context * sx)
786 {
787 BOOL good_response = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
788 '2', (SOB sx->conn_args.ob)->command_timeout);
789 #ifdef EXPERIMENTAL_DSN_INFO
790 sx->smtp_greeting = string_copy(sx->buffer);
791 #endif
792 return good_response;
793 }
794
795 static BOOL
796 smtp_reap_ehlo(smtp_context * sx)
797 {
798 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
799 (SOB sx->conn_args.ob)->command_timeout))
800 {
801 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
802 {
803 #ifdef EXPERIMENTAL_DSN_INFO
804 sx->helo_response = string_copy(sx->buffer);
805 #endif
806 return FALSE;
807 }
808 sx->esmtp = FALSE;
809 }
810 #ifdef EXPERIMENTAL_DSN_INFO
811 sx->helo_response = string_copy(sx->buffer);
812 #endif
813 return TRUE;
814 }
815
816
817
818 #ifdef EXPERIMENTAL_PIPE_CONNECT
819 static uschar *
820 ehlo_cache_key(const smtp_context * sx)
821 {
822 host_item * host = sx->conn_args.host;
823 return Ustrchr(host->address, ':')
824 ? string_sprintf("[%s]:%d.EHLO", host->address,
825 host->port == PORT_NONE ? sx->port : host->port)
826 : string_sprintf("%s:%d.EHLO", host->address,
827 host->port == PORT_NONE ? sx->port : host->port);
828 }
829
830 static void
831 write_ehlo_cache_entry(const smtp_context * sx)
832 {
833 open_db dbblock, * dbm_file;
834
835 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
836 {
837 uschar * ehlo_resp_key = ehlo_cache_key(sx);
838 dbdata_ehlo_resp er = { .data = sx->ehlo_resp };
839
840 HDEBUG(D_transport) debug_printf("writing clr %04x/%04x cry %04x/%04x\n",
841 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
842 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths);
843
844 dbfn_write(dbm_file, ehlo_resp_key, &er, (int)sizeof(er));
845 dbfn_close(dbm_file);
846 }
847 }
848
849 static void
850 invalidate_ehlo_cache_entry(smtp_context * sx)
851 {
852 open_db dbblock, * dbm_file;
853
854 if ( sx->early_pipe_active
855 && (dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
856 {
857 uschar * ehlo_resp_key = ehlo_cache_key(sx);
858 dbfn_delete(dbm_file, ehlo_resp_key);
859 dbfn_close(dbm_file);
860 }
861 }
862
863 static BOOL
864 read_ehlo_cache_entry(smtp_context * sx)
865 {
866 open_db dbblock;
867 open_db * dbm_file;
868
869 if (!(dbm_file = dbfn_open(US"misc", O_RDONLY, &dbblock, FALSE, TRUE)))
870 { DEBUG(D_transport) debug_printf("ehlo-cache: no misc DB\n"); }
871 else
872 {
873 uschar * ehlo_resp_key = ehlo_cache_key(sx);
874 dbdata_ehlo_resp * er;
875
876 if (!(er = dbfn_read(dbm_file, ehlo_resp_key)))
877 { DEBUG(D_transport) debug_printf("no ehlo-resp record\n"); }
878 else if (time(NULL) - er->time_stamp > retry_data_expire)
879 {
880 DEBUG(D_transport) debug_printf("ehlo-resp record too old\n");
881 dbfn_close(dbm_file);
882 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
883 dbfn_delete(dbm_file, ehlo_resp_key);
884 }
885 else
886 {
887 sx->ehlo_resp = er->data;
888 dbfn_close(dbm_file);
889 DEBUG(D_transport) debug_printf(
890 "EHLO response bits from cache: cleartext 0x%04x crypted 0x%04x\n",
891 er->data.cleartext_features, er->data.crypted_features);
892 return TRUE;
893 }
894 dbfn_close(dbm_file);
895 }
896 return FALSE;
897 }
898
899
900
901 /* Return an auths bitmap for the set of AUTH methods offered by the server
902 which match our authenticators. */
903
904 static unsigned short
905 study_ehlo_auths(smtp_context * sx)
906 {
907 uschar * names;
908 auth_instance * au;
909 uschar authnum;
910 unsigned short authbits = 0;
911
912 if (!sx->esmtp) return 0;
913 if (!regex_AUTH) regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
914 if (!regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)) return 0;
915 expand_nmax = -1; /* reset */
916 names = string_copyn(expand_nstring[1], expand_nlength[1]);
917
918 for (au = auths, authnum = 0; au; au = au->next, authnum++) if (au->client)
919 {
920 const uschar * list = names;
921 int sep = ' ';
922 uschar name[32];
923
924 while (string_nextinlist(&list, &sep, name, sizeof(name)))
925 if (strcmpic(au->public_name, name) == 0)
926 { authbits |= BIT(authnum); break; }
927 }
928
929 DEBUG(D_transport)
930 debug_printf("server offers %s AUTH, methods '%s', bitmap 0x%04x\n",
931 tls_out.active.sock >= 0 ? "crypted" : "plaintext", names, authbits);
932
933 if (tls_out.active.sock >= 0)
934 sx->ehlo_resp.crypted_auths = authbits;
935 else
936 sx->ehlo_resp.cleartext_auths = authbits;
937 return authbits;
938 }
939
940
941
942
943 /* Wait for and check responses for early-pipelining.
944
945 Called from the lower-level smtp_read_response() function
946 used for general code that assume synchronisation, if context
947 flags indicate outstanding early-pipelining commands. Also
948 called fom sync_responses() which handles pipelined commands.
949
950 Arguments:
951 sx smtp connection context
952 countp number of outstanding responses, adjusted on return
953
954 Return:
955 OK all well
956 DEFER error on first read of TLS'd conn
957 FAIL SMTP error in response
958 */
959 int
960 smtp_reap_early_pipe(smtp_context * sx, int * countp)
961 {
962 BOOL pending_BANNER = sx->pending_BANNER;
963 BOOL pending_EHLO = sx->pending_EHLO;
964 int rc = FAIL;
965
966 sx->pending_BANNER = FALSE; /* clear early to avoid recursion */
967 sx->pending_EHLO = FALSE;
968
969 if (pending_BANNER)
970 {
971 DEBUG(D_transport) debug_printf("%s expect banner\n", __FUNCTION__);
972 (*countp)--;
973 if (!smtp_reap_banner(sx))
974 {
975 DEBUG(D_transport) debug_printf("bad banner\n");
976 if (tls_out.active.sock >= 0) rc = DEFER;
977 goto fail;
978 }
979 }
980
981 if (pending_EHLO)
982 {
983 unsigned peer_offered;
984 unsigned short authbits = 0, * ap;
985
986 DEBUG(D_transport) debug_printf("%s expect ehlo\n", __FUNCTION__);
987 (*countp)--;
988 if (!smtp_reap_ehlo(sx))
989 {
990 DEBUG(D_transport) debug_printf("bad response for EHLO\n");
991 if (tls_out.active.sock >= 0) rc = DEFER;
992 goto fail;
993 }
994
995 /* Compare the actual EHLO response to the cached value we assumed;
996 on difference, dump or rewrite the cache and arrange for a retry. */
997
998 ap = tls_out.active.sock < 0
999 ? &sx->ehlo_resp.cleartext_auths : &sx->ehlo_resp.crypted_auths;
1000
1001 peer_offered = ehlo_response(sx->buffer,
1002 (tls_out.active.sock < 0 ? OPTION_TLS : 0)
1003 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
1004 | OPTION_UTF8 | OPTION_EARLY_PIPE
1005 );
1006 if ( peer_offered != sx->peer_offered
1007 || (authbits = study_ehlo_auths(sx)) != *ap)
1008 {
1009 HDEBUG(D_transport)
1010 debug_printf("EHLO %s extensions changed, 0x%04x/0x%04x -> 0x%04x/0x%04x\n",
1011 tls_out.active.sock < 0 ? "cleartext" : "crypted",
1012 sx->peer_offered, *ap, peer_offered, authbits);
1013 *(tls_out.active.sock < 0
1014 ? &sx->ehlo_resp.cleartext_features : &sx->ehlo_resp.crypted_features) = peer_offered;
1015 *ap = authbits;
1016 if (peer_offered & OPTION_EARLY_PIPE)
1017 write_ehlo_cache_entry(sx);
1018 else
1019 invalidate_ehlo_cache_entry(sx);
1020
1021 return OK; /* just carry on */
1022 }
1023 }
1024 return OK;
1025
1026 fail:
1027 invalidate_ehlo_cache_entry(sx);
1028 (void) smtp_discard_responses(sx, sx->conn_args.ob, *countp);
1029 return rc;
1030 }
1031 #endif
1032
1033
1034 /*************************************************
1035 * Synchronize SMTP responses *
1036 *************************************************/
1037
1038 /* This function is called from smtp_deliver() to receive SMTP responses from
1039 the server, and match them up with the commands to which they relate. When
1040 PIPELINING is not in use, this function is called after every command, and is
1041 therefore somewhat over-engineered, but it is simpler to use a single scheme
1042 that works both with and without PIPELINING instead of having two separate sets
1043 of code.
1044
1045 The set of commands that are buffered up with pipelining may start with MAIL
1046 and may end with DATA; in between are RCPT commands that correspond to the
1047 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
1048 etc.) are never buffered.
1049
1050 Errors after MAIL or DATA abort the whole process leaving the response in the
1051 buffer. After MAIL, pending responses are flushed, and the original command is
1052 re-instated in big_buffer for error messages. For RCPT commands, the remote is
1053 permitted to reject some recipient addresses while accepting others. However
1054 certain errors clearly abort the whole process. Set the value in
1055 transport_return to PENDING_OK if the address is accepted. If there is a
1056 subsequent general error, it will get reset accordingly. If not, it will get
1057 converted to OK at the end.
1058
1059 Arguments:
1060 sx smtp connection context
1061 count the number of responses to read
1062 pending_DATA 0 if last command sent was not DATA
1063 +1 if previously had a good recipient
1064 -1 if not previously had a good recipient
1065
1066 Returns: 3 if at least one address had 2xx and one had 5xx
1067 2 if at least one address had 5xx but none had 2xx
1068 1 if at least one host had a 2xx response, but none had 5xx
1069 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
1070 -1 timeout while reading RCPT response
1071 -2 I/O or other non-response error for RCPT
1072 -3 DATA or MAIL failed - errno and buffer set
1073 -4 banner or EHLO failed (early-pipelining)
1074 -5 banner or EHLO failed (early-pipelining, TLS)
1075 */
1076
1077 static int
1078 sync_responses(smtp_context * sx, int count, int pending_DATA)
1079 {
1080 address_item * addr = sx->sync_addr;
1081 smtp_transport_options_block * ob = sx->conn_args.ob;
1082 int yield = 0;
1083
1084 #ifdef EXPERIMENTAL_PIPE_CONNECT
1085 int rc;
1086 if ((rc = smtp_reap_early_pipe(sx, &count)) != OK)
1087 return rc == FAIL ? -4 : -5;
1088 #endif
1089
1090 /* Handle the response for a MAIL command. On error, reinstate the original
1091 command in big_buffer for error message use, and flush any further pending
1092 responses before returning, except after I/O errors and timeouts. */
1093
1094 if (sx->pending_MAIL)
1095 {
1096 DEBUG(D_transport) debug_printf("%s expect mail\n", __FUNCTION__);
1097 count--;
1098 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1099 '2', ob->command_timeout))
1100 {
1101 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
1102 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
1103 if (errno == ERRNO_TLSFAILURE)
1104 return -5;
1105 if (errno == 0 && sx->buffer[0] != 0)
1106 {
1107 int save_errno = 0;
1108 if (sx->buffer[0] == '4')
1109 {
1110 save_errno = ERRNO_MAIL4XX;
1111 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1112 }
1113 count = smtp_discard_responses(sx, ob, count);
1114 errno = save_errno;
1115 }
1116
1117 if (pending_DATA) count--; /* Number of RCPT responses to come */
1118 while (count-- > 0) /* Mark any pending addrs with the host used */
1119 {
1120 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
1121 addr->host_used = sx->conn_args.host;
1122 addr = addr->next;
1123 }
1124 return -3;
1125 }
1126 }
1127
1128 if (pending_DATA) count--; /* Number of RCPT responses to come */
1129
1130 /* Read and handle the required number of RCPT responses, matching each one up
1131 with an address by scanning for the next address whose status is PENDING_DEFER.
1132 */
1133
1134 while (count-- > 0)
1135 {
1136 while (addr->transport_return != PENDING_DEFER)
1137 if (!(addr = addr->next))
1138 return -2;
1139
1140 /* The address was accepted */
1141 addr->host_used = sx->conn_args.host;
1142
1143 DEBUG(D_transport) debug_printf("%s expect rcpt\n", __FUNCTION__);
1144 if (smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1145 '2', ob->command_timeout))
1146 {
1147 yield |= 1;
1148 addr->transport_return = PENDING_OK;
1149
1150 /* If af_dr_retry_exists is set, there was a routing delay on this address;
1151 ensure that any address-specific retry record is expunged. We do this both
1152 for the basic key and for the version that also includes the sender. */
1153
1154 if (testflag(addr, af_dr_retry_exists))
1155 {
1156 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
1157 sender_address);
1158 retry_add_item(addr, altkey, rf_delete);
1159 retry_add_item(addr, addr->address_retry_key, rf_delete);
1160 }
1161 }
1162
1163 /* Error on first TLS read */
1164
1165 else if (errno == ERRNO_TLSFAILURE)
1166 return -5;
1167
1168 /* Timeout while reading the response */
1169
1170 else if (errno == ETIMEDOUT)
1171 {
1172 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
1173 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1174 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
1175 retry_add_item(addr, addr->address_retry_key, 0);
1176 update_waiting = FALSE;
1177 return -1;
1178 }
1179
1180 /* Handle other errors in obtaining an SMTP response by returning -1. This
1181 will cause all the addresses to be deferred. Restore the SMTP command in
1182 big_buffer for which we are checking the response, so the error message
1183 makes sense. */
1184
1185 else if (errno != 0 || sx->buffer[0] == 0)
1186 {
1187 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
1188 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1189 return -2;
1190 }
1191
1192 /* Handle SMTP permanent and temporary response codes. */
1193
1194 else
1195 {
1196 addr->message =
1197 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
1198 "%s", transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes),
1199 string_printing(sx->buffer));
1200 setflag(addr, af_pass_message);
1201 if (!sx->verify)
1202 msglog_line(sx->conn_args.host, addr->message);
1203
1204 /* The response was 5xx */
1205
1206 if (sx->buffer[0] == '5')
1207 {
1208 addr->transport_return = FAIL;
1209 yield |= 2;
1210 }
1211
1212 /* The response was 4xx */
1213
1214 else
1215 {
1216 addr->transport_return = DEFER;
1217 addr->basic_errno = ERRNO_RCPT4XX;
1218 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1219
1220 if (!sx->verify)
1221 {
1222 #ifndef DISABLE_EVENT
1223 event_defer_errno = addr->more_errno;
1224 msg_event_raise(US"msg:rcpt:host:defer", addr);
1225 #endif
1226
1227 /* Log temporary errors if there are more hosts to be tried.
1228 If not, log this last one in the == line. */
1229
1230 if (sx->conn_args.host->next)
1231 if (LOGGING(outgoing_port))
1232 log_write(0, LOG_MAIN, "H=%s [%s]:%d %s", sx->conn_args.host->name,
1233 sx->conn_args.host->address,
1234 sx->port == PORT_NONE ? 25 : sx->port, addr->message);
1235 else
1236 log_write(0, LOG_MAIN, "H=%s [%s]: %s", sx->conn_args.host->name,
1237 sx->conn_args.host->address, addr->message);
1238
1239 #ifndef DISABLE_EVENT
1240 else
1241 msg_event_raise(US"msg:rcpt:defer", addr);
1242 #endif
1243
1244 /* Do not put this message on the list of those waiting for specific
1245 hosts, as otherwise it is likely to be tried too often. */
1246
1247 update_waiting = FALSE;
1248
1249 /* Add a retry item for the address so that it doesn't get tried again
1250 too soon. If address_retry_include_sender is true, add the sender address
1251 to the retry key. */
1252
1253 retry_add_item(addr,
1254 ob->address_retry_include_sender
1255 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
1256 : addr->address_retry_key,
1257 0);
1258 }
1259 }
1260 }
1261 } /* Loop for next RCPT response */
1262
1263 /* Update where to start at for the next block of responses, unless we
1264 have already handled all the addresses. */
1265
1266 if (addr) sx->sync_addr = addr->next;
1267
1268 /* Handle a response to DATA. If we have not had any good recipients, either
1269 previously or in this block, the response is ignored. */
1270
1271 if (pending_DATA != 0)
1272 {
1273 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1274 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1275 '3', ob->command_timeout))
1276 {
1277 int code;
1278 uschar *msg;
1279 BOOL pass_message;
1280
1281 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1282 return -5;
1283
1284 if (pending_DATA > 0 || (yield & 1) != 0)
1285 {
1286 if (errno == 0 && sx->buffer[0] == '4')
1287 {
1288 errno = ERRNO_DATA4XX;
1289 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1290 }
1291 return -3;
1292 }
1293 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1294 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1295 "is in use and there were no good recipients\n", msg);
1296 }
1297 }
1298
1299 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1300 present) received 3xx. If any RCPTs were handled and yielded anything other
1301 than 4xx, yield will be set non-zero. */
1302
1303 return yield;
1304 }
1305
1306
1307
1308
1309
1310 /* Try an authenticator's client entry */
1311
1312 static int
1313 try_authenticator(smtp_context * sx, auth_instance * au)
1314 {
1315 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1316 host_item * host = sx->conn_args.host; /* host to deliver to */
1317 int rc;
1318
1319 sx->outblock.authenticating = TRUE;
1320 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1321 sx->buffer, sizeof(sx->buffer));
1322 sx->outblock.authenticating = FALSE;
1323 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n", au->name, rc);
1324
1325 /* A temporary authentication failure must hold up delivery to
1326 this host. After a permanent authentication failure, we carry on
1327 to try other authentication methods. If all fail hard, try to
1328 deliver the message unauthenticated unless require_auth was set. */
1329
1330 switch(rc)
1331 {
1332 case OK:
1333 f.smtp_authenticated = TRUE; /* stops the outer loop */
1334 client_authenticator = au->name;
1335 if (au->set_client_id)
1336 client_authenticated_id = expand_string(au->set_client_id);
1337 break;
1338
1339 /* Failure after writing a command */
1340
1341 case FAIL_SEND:
1342 return FAIL_SEND;
1343
1344 /* Failure after reading a response */
1345
1346 case FAIL:
1347 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1348 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1349 au->name, host->name, host->address, sx->buffer);
1350 break;
1351
1352 /* Failure by some other means. In effect, the authenticator
1353 decided it wasn't prepared to handle this case. Typically this
1354 is the result of "fail" in an expansion string. Do we need to
1355 log anything here? Feb 2006: a message is now put in the buffer
1356 if logging is required. */
1357
1358 case CANCELLED:
1359 if (*sx->buffer != 0)
1360 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1361 "authentication H=%s [%s] %s", au->name, host->name,
1362 host->address, sx->buffer);
1363 break;
1364
1365 /* Internal problem, message in buffer. */
1366
1367 case ERROR:
1368 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1369 DEFER, FALSE);
1370 return ERROR;
1371 }
1372 return OK;
1373 }
1374
1375
1376
1377
1378 /* Do the client side of smtp-level authentication.
1379
1380 Arguments:
1381 sx smtp connection context
1382
1383 sx->buffer should have the EHLO response from server (gets overwritten)
1384
1385 Returns:
1386 OK Success, or failed (but not required): global "smtp_authenticated" set
1387 DEFER Failed authentication (and was required)
1388 ERROR Internal problem
1389
1390 FAIL_SEND Failed communications - transmit
1391 FAIL - response
1392 */
1393
1394 static int
1395 smtp_auth(smtp_context * sx)
1396 {
1397 host_item * host = sx->conn_args.host; /* host to deliver to */
1398 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1399 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1400 #ifdef EXPERIMENTAL_PIPE_CONNECT
1401 unsigned short authbits = tls_out.active.sock >= 0
1402 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1403 #endif
1404 uschar * fail_reason = US"server did not advertise AUTH support";
1405
1406 f.smtp_authenticated = FALSE;
1407 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1408
1409 if (!regex_AUTH)
1410 regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
1411
1412 /* Is the server offering AUTH? */
1413
1414 if ( sx->esmtp
1415 &&
1416 #ifdef EXPERIMENTAL_PIPE_CONNECT
1417 sx->early_pipe_active ? authbits
1418 :
1419 #endif
1420 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1421 )
1422 {
1423 uschar * names = NULL;
1424 expand_nmax = -1; /* reset */
1425
1426 #ifdef EXPERIMENTAL_PIPE_CONNECT
1427 if (!sx->early_pipe_active)
1428 #endif
1429 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1430
1431 /* Must not do this check until after we have saved the result of the
1432 regex match above as the check could be another RE. */
1433
1434 if ( require_auth == OK
1435 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1436 {
1437 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1438 fail_reason = US"no common mechanisms were found";
1439
1440 #ifdef EXPERIMENTAL_PIPE_CONNECT
1441 if (sx->early_pipe_active)
1442 {
1443 /* Scan our authenticators (which support use by a client and were offered
1444 by the server (checked at cache-write time)), not suppressed by
1445 client_condition. If one is found, attempt to authenticate by calling its
1446 client function. We are limited to supporting up to 16 authenticator
1447 public-names by the number of bits in a short. */
1448
1449 auth_instance * au;
1450 uschar bitnum;
1451 int rc;
1452
1453 for (bitnum = 0, au = auths;
1454 !f.smtp_authenticated && au && bitnum < 16;
1455 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1456 {
1457 if ( au->client_condition
1458 && !expand_check_condition(au->client_condition, au->name,
1459 US"client authenticator"))
1460 {
1461 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1462 au->name, "client_condition is false");
1463 continue;
1464 }
1465
1466 /* Found data for a listed mechanism. Call its client entry. Set
1467 a flag in the outblock so that data is overwritten after sending so
1468 that reflections don't show it. */
1469
1470 fail_reason = US"authentication attempt(s) failed";
1471
1472 if ((rc = try_authenticator(sx, au)) != OK)
1473 return rc;
1474 }
1475 }
1476 else
1477 #endif
1478
1479 /* Scan the configured authenticators looking for one which is configured
1480 for use as a client, which is not suppressed by client_condition, and
1481 whose name matches an authentication mechanism supported by the server.
1482 If one is found, attempt to authenticate by calling its client function.
1483 */
1484
1485 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1486 {
1487 uschar *p = names;
1488
1489 if ( !au->client
1490 || ( au->client_condition
1491 && !expand_check_condition(au->client_condition, au->name,
1492 US"client authenticator")))
1493 {
1494 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1495 au->name,
1496 (au->client)? "client_condition is false" :
1497 "not configured as a client");
1498 continue;
1499 }
1500
1501 /* Loop to scan supported server mechanisms */
1502
1503 while (*p)
1504 {
1505 int len = Ustrlen(au->public_name);
1506 int rc;
1507
1508 while (isspace(*p)) p++;
1509
1510 if (strncmpic(au->public_name, p, len) != 0 ||
1511 (p[len] != 0 && !isspace(p[len])))
1512 {
1513 while (*p != 0 && !isspace(*p)) p++;
1514 continue;
1515 }
1516
1517 /* Found data for a listed mechanism. Call its client entry. Set
1518 a flag in the outblock so that data is overwritten after sending so
1519 that reflections don't show it. */
1520
1521 fail_reason = US"authentication attempt(s) failed";
1522
1523 if ((rc = try_authenticator(sx, au)) != OK)
1524 return rc;
1525
1526 break; /* If not authenticated, try next authenticator */
1527 } /* Loop for scanning supported server mechanisms */
1528 } /* Loop for further authenticators */
1529 }
1530 }
1531
1532 /* If we haven't authenticated, but are required to, give up. */
1533
1534 if (require_auth == OK && !f.smtp_authenticated)
1535 {
1536 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1537 string_sprintf("authentication required but %s", fail_reason), DEFER,
1538 FALSE);
1539 return DEFER;
1540 }
1541
1542 return OK;
1543 }
1544
1545
1546 /* Construct AUTH appendix string for MAIL TO */
1547 /*
1548 Arguments
1549 buffer to build string
1550 addrlist chain of potential addresses to deliver
1551 ob transport options
1552
1553 Globals f.smtp_authenticated
1554 client_authenticated_sender
1555 Return True on error, otherwise buffer has (possibly empty) terminated string
1556 */
1557
1558 BOOL
1559 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1560 smtp_transport_options_block *ob)
1561 {
1562 uschar *local_authenticated_sender = authenticated_sender;
1563
1564 #ifdef notdef
1565 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1566 #endif
1567
1568 if (ob->authenticated_sender != NULL)
1569 {
1570 uschar *new = expand_string(ob->authenticated_sender);
1571 if (new == NULL)
1572 {
1573 if (!f.expand_string_forcedfail)
1574 {
1575 uschar *message = string_sprintf("failed to expand "
1576 "authenticated_sender: %s", expand_string_message);
1577 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1578 return TRUE;
1579 }
1580 }
1581 else if (new[0] != 0) local_authenticated_sender = new;
1582 }
1583
1584 /* Add the authenticated sender address if present */
1585
1586 if ((f.smtp_authenticated || ob->authenticated_sender_force) &&
1587 local_authenticated_sender != NULL)
1588 {
1589 string_format(buffer, bufsize, " AUTH=%s",
1590 auth_xtextencode(local_authenticated_sender,
1591 Ustrlen(local_authenticated_sender)));
1592 client_authenticated_sender = string_copy(local_authenticated_sender);
1593 }
1594 else
1595 *buffer= 0;
1596
1597 return FALSE;
1598 }
1599
1600
1601
1602 #ifdef SUPPORT_DANE
1603 /* Lookup TLSA record for host/port.
1604 Return: OK success with dnssec; DANE mode
1605 DEFER Do not use this host now, may retry later
1606 FAIL_FORCED No TLSA record; DANE not usable
1607 FAIL Do not use this connection
1608 */
1609
1610 int
1611 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1612 {
1613 /* move this out to host.c given the similarity to dns_lookup() ? */
1614 uschar buffer[300];
1615 const uschar * fullname = buffer;
1616 int rc;
1617 BOOL sec;
1618
1619 /* TLSA lookup string */
1620 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1621
1622 rc = dns_lookup(dnsa, buffer, T_TLSA, &fullname);
1623 sec = dns_is_secure(dnsa);
1624 DEBUG(D_transport)
1625 debug_printf("TLSA lookup ret %d %sDNSSEC\n", rc, sec ? "" : "not ");
1626
1627 switch (rc)
1628 {
1629 case DNS_AGAIN:
1630 return DEFER; /* just defer this TLS'd conn */
1631
1632 case DNS_SUCCEED:
1633 if (sec)
1634 {
1635 DEBUG(D_transport)
1636 {
1637 dns_scan dnss;
1638 for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
1639 rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
1640 if (rr->type == T_TLSA && rr->size > 3)
1641 {
1642 uint16_t payload_length = rr->size - 3;
1643 uschar s[MAX_TLSA_EXPANDED_SIZE], * sp = s, * p = US rr->data;
1644
1645 sp += sprintf(CS sp, "%d ", *p++); /* usage */
1646 sp += sprintf(CS sp, "%d ", *p++); /* selector */
1647 sp += sprintf(CS sp, "%d ", *p++); /* matchtype */
1648 while (payload_length-- > 0 && sp-s < (MAX_TLSA_EXPANDED_SIZE - 4))
1649 sp += sprintf(CS sp, "%02x", *p++);
1650
1651 debug_printf(" %s\n", s);
1652 }
1653 }
1654 return OK;
1655 }
1656 log_write(0, LOG_MAIN,
1657 "DANE error: TLSA lookup for %s not DNSSEC", host->name);
1658 /*FALLTRHOUGH*/
1659
1660 case DNS_NODATA: /* no TLSA RR for this lookup */
1661 case DNS_NOMATCH: /* no records at all for this lookup */
1662 return dane_required ? FAIL : FAIL_FORCED;
1663
1664 default:
1665 case DNS_FAIL:
1666 return dane_required ? FAIL : DEFER;
1667 }
1668 }
1669 #endif
1670
1671
1672
1673 typedef struct smtp_compare_s
1674 {
1675 uschar *current_sender_address;
1676 struct transport_instance *tblock;
1677 } smtp_compare_t;
1678
1679
1680 /* Create a unique string that identifies this message, it is based on
1681 sender_address, helo_data and tls_certificate if enabled.
1682 */
1683
1684 static uschar *
1685 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1686 {
1687 address_item * addr1;
1688 uschar * if1 = US"";
1689 uschar * helo1 = US"";
1690 #ifndef DISABLE_TLS
1691 uschar * tlsc1 = US"";
1692 #endif
1693 uschar * save_sender_address = sender_address;
1694 uschar * local_identity = NULL;
1695 smtp_transport_options_block * ob = SOB tblock->options_block;
1696
1697 sender_address = sender;
1698
1699 addr1 = deliver_make_addr (sender, TRUE);
1700 deliver_set_expansions(addr1);
1701
1702 if (ob->interface)
1703 if1 = expand_string(ob->interface);
1704
1705 if (ob->helo_data)
1706 helo1 = expand_string(ob->helo_data);
1707
1708 #ifndef DISABLE_TLS
1709 if (ob->tls_certificate)
1710 tlsc1 = expand_string(ob->tls_certificate);
1711 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1712 #else
1713 local_identity = string_sprintf ("%s^%s", if1, helo1);
1714 #endif
1715
1716 deliver_set_expansions(NULL);
1717 sender_address = save_sender_address;
1718
1719 return local_identity;
1720 }
1721
1722
1723
1724 /* This routine is a callback that is called from transport_check_waiting.
1725 This function will evaluate the incoming message versus the previous
1726 message. If the incoming message is using a different local identity then
1727 we will veto this new message. */
1728
1729 static BOOL
1730 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1731 {
1732 uschar * message_local_identity,
1733 * current_local_identity,
1734 * new_sender_address;
1735
1736 current_local_identity =
1737 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1738
1739 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1740 return 0;
1741
1742 message_local_identity =
1743 smtp_local_identity(new_sender_address, s_compare->tblock);
1744
1745 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1746 }
1747
1748
1749
1750 static unsigned
1751 ehlo_response(uschar * buf, unsigned checks)
1752 {
1753 size_t bsize = Ustrlen(buf);
1754
1755 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1756
1757 #ifndef DISABLE_TLS
1758 if ( checks & OPTION_TLS
1759 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1760 #endif
1761 checks &= ~OPTION_TLS;
1762
1763 if ( checks & OPTION_IGNQ
1764 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1765 PCRE_EOPT, NULL, 0) < 0)
1766 checks &= ~OPTION_IGNQ;
1767
1768 if ( checks & OPTION_CHUNKING
1769 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1770 checks &= ~OPTION_CHUNKING;
1771
1772 #ifndef DISABLE_PRDR
1773 if ( checks & OPTION_PRDR
1774 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1775 #endif
1776 checks &= ~OPTION_PRDR;
1777
1778 #ifdef SUPPORT_I18N
1779 if ( checks & OPTION_UTF8
1780 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1781 #endif
1782 checks &= ~OPTION_UTF8;
1783
1784 if ( checks & OPTION_DSN
1785 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1786 checks &= ~OPTION_DSN;
1787
1788 if ( checks & OPTION_PIPE
1789 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1790 PCRE_EOPT, NULL, 0) < 0)
1791 checks &= ~OPTION_PIPE;
1792
1793 if ( checks & OPTION_SIZE
1794 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1795 checks &= ~OPTION_SIZE;
1796
1797 #ifdef EXPERIMENTAL_PIPE_CONNECT
1798 if ( checks & OPTION_EARLY_PIPE
1799 && pcre_exec(regex_EARLY_PIPE, NULL, CS buf, bsize, 0,
1800 PCRE_EOPT, NULL, 0) < 0)
1801 #endif
1802 checks &= ~OPTION_EARLY_PIPE;
1803
1804 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1805 return checks;
1806 }
1807
1808
1809
1810 /* Callback for emitting a BDAT data chunk header.
1811
1812 If given a nonzero size, first flush any buffered SMTP commands
1813 then emit the command.
1814
1815 Reap previous SMTP command responses if requested, and always reap
1816 the response from a previous BDAT command.
1817
1818 Args:
1819 tctx transport context
1820 chunk_size value for SMTP BDAT command
1821 flags
1822 tc_chunk_last add LAST option to SMTP BDAT command
1823 tc_reap_prev reap response to previous SMTP commands
1824
1825 Returns:
1826 OK or ERROR
1827 DEFER TLS error on first read (EHLO-resp); errno set
1828 */
1829
1830 static int
1831 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1832 unsigned flags)
1833 {
1834 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1835 smtp_context * sx = tctx->smtp_context;
1836 int cmd_count = 0;
1837 int prev_cmd_count;
1838
1839 /* Write SMTP chunk header command. If not reaping responses, note that
1840 there may be more writes (like, the chunk data) done soon. */
1841
1842 if (chunk_size > 0)
1843 {
1844 #ifdef EXPERIMENTAL_PIPE_CONNECT
1845 BOOL new_conn = !!(sx->outblock.conn_args);
1846 #endif
1847 if((cmd_count = smtp_write_command(sx,
1848 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1849 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1850 ) < 0) return ERROR;
1851 if (flags & tc_chunk_last)
1852 data_command = string_copy(big_buffer); /* Save for later error message */
1853 #ifdef EXPERIMENTAL_PIPE_CONNECT
1854 /* That command write could have been the one that made the connection.
1855 Copy the fd from the client conn ctx (smtp transport specific) to the
1856 generic transport ctx. */
1857
1858 if (new_conn)
1859 tctx->u.fd = sx->outblock.cctx->sock;
1860 #endif
1861 }
1862
1863 prev_cmd_count = cmd_count += sx->cmd_count;
1864
1865 /* Reap responses for any previous, but not one we just emitted */
1866
1867 if (chunk_size > 0)
1868 prev_cmd_count--;
1869 if (sx->pending_BDAT)
1870 prev_cmd_count--;
1871
1872 if (flags & tc_reap_prev && prev_cmd_count > 0)
1873 {
1874 DEBUG(D_transport) debug_printf("look for %d responses"
1875 " for previous pipelined cmds\n", prev_cmd_count);
1876
1877 switch(sync_responses(sx, prev_cmd_count, 0))
1878 {
1879 case 1: /* 2xx (only) => OK */
1880 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1881 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1882 case 0: break; /* No 2xx or 5xx, but no probs */
1883
1884 case -5: errno = ERRNO_TLSFAILURE;
1885 return DEFER;
1886 #ifdef EXPERIMENTAL_PIPE_CONNECT
1887 case -4: /* non-2xx for pipelined banner or EHLO */
1888 #endif
1889 case -1: /* Timeout on RCPT */
1890 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1891 }
1892 cmd_count = 1;
1893 if (!sx->pending_BDAT)
1894 pipelining_active = FALSE;
1895 }
1896
1897 /* Reap response for an outstanding BDAT */
1898
1899 if (sx->pending_BDAT)
1900 {
1901 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1902
1903 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
1904 ob->command_timeout))
1905 {
1906 if (errno == 0 && sx->buffer[0] == '4')
1907 {
1908 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1909 sx->addrlist->more_errno |=
1910 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1911 }
1912 return ERROR;
1913 }
1914 cmd_count--;
1915 sx->pending_BDAT = FALSE;
1916 pipelining_active = FALSE;
1917 }
1918 else if (chunk_size > 0)
1919 sx->pending_BDAT = TRUE;
1920
1921
1922 sx->cmd_count = cmd_count;
1923 return OK;
1924 }
1925
1926
1927
1928
1929
1930 /*************************************************
1931 * Make connection for given message *
1932 *************************************************/
1933
1934 /*
1935 Arguments:
1936 ctx connection context
1937 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1938 a second attempt after TLS initialization fails
1939
1940 Returns: OK - the connection was made and the delivery attempted;
1941 fd is set in the conn context, tls_out set up.
1942 DEFER - the connection could not be made, or something failed
1943 while setting up the SMTP session, or there was a
1944 non-message-specific error, such as a timeout.
1945 ERROR - helo_data or add_headers or authenticated_sender is
1946 specified for this transport, and the string failed
1947 to expand
1948 */
1949 int
1950 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1951 {
1952 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
1953 BOOL pass_message = FALSE;
1954 uschar * message = NULL;
1955 int yield = OK;
1956 int rc;
1957 #ifndef DISABLE_TLS
1958 uschar * tls_errstr;
1959 #endif
1960
1961 sx->conn_args.ob = ob;
1962
1963 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1964 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
1965 sx->ok = FALSE;
1966 sx->send_rset = TRUE;
1967 sx->send_quit = TRUE;
1968 sx->setting_up = TRUE;
1969 sx->esmtp = TRUE;
1970 sx->esmtp_sent = FALSE;
1971 #ifdef SUPPORT_I18N
1972 sx->utf8_needed = FALSE;
1973 #endif
1974 sx->dsn_all_lasthop = TRUE;
1975 #ifdef SUPPORT_DANE
1976 sx->conn_args.dane = FALSE;
1977 sx->dane_required =
1978 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
1979 #endif
1980 #ifdef EXPERIMENTAL_PIPE_CONNECT
1981 sx->early_pipe_active = sx->early_pipe_ok = FALSE;
1982 sx->ehlo_resp.cleartext_features = sx->ehlo_resp.crypted_features = 0;
1983 sx->pending_BANNER = sx->pending_EHLO = FALSE;
1984 #endif
1985
1986 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1987 sx->peer_offered = 0;
1988 sx->avoid_option = 0;
1989 sx->igquotstr = US"";
1990 if (!sx->helo_data) sx->helo_data = ob->helo_data;
1991 #ifdef EXPERIMENTAL_DSN_INFO
1992 sx->smtp_greeting = NULL;
1993 sx->helo_response = NULL;
1994 #endif
1995
1996 smtp_command = US"initial connection";
1997 sx->buffer[0] = '\0';
1998
1999 /* Set up the buffer for reading SMTP response packets. */
2000
2001 sx->inblock.buffer = sx->inbuffer;
2002 sx->inblock.buffersize = sizeof(sx->inbuffer);
2003 sx->inblock.ptr = sx->inbuffer;
2004 sx->inblock.ptrend = sx->inbuffer;
2005
2006 /* Set up the buffer for holding SMTP commands while pipelining */
2007
2008 sx->outblock.buffer = sx->outbuffer;
2009 sx->outblock.buffersize = sizeof(sx->outbuffer);
2010 sx->outblock.ptr = sx->outbuffer;
2011 sx->outblock.cmd_count = 0;
2012 sx->outblock.authenticating = FALSE;
2013 sx->outblock.conn_args = NULL;
2014
2015 /* Reset the parameters of a TLS session. */
2016
2017 tls_out.bits = 0;
2018 tls_out.cipher = NULL; /* the one we may use for this transport */
2019 tls_out.ourcert = NULL;
2020 tls_out.peercert = NULL;
2021 tls_out.peerdn = NULL;
2022 #ifdef USE_OPENSSL
2023 tls_out.sni = NULL;
2024 #endif
2025 tls_out.ocsp = OCSP_NOT_REQ;
2026 #ifdef EXPERIMENTAL_TLS_RESUME
2027 tls_out.resumption = 0;
2028 #endif
2029
2030 /* Flip the legacy TLS-related variables over to the outbound set in case
2031 they're used in the context of the transport. Don't bother resetting
2032 afterward (when being used by a transport) as we're in a subprocess.
2033 For verify, unflipped once the callout is dealt with */
2034
2035 tls_modify_variables(&tls_out);
2036
2037 #ifdef DISABLE_TLS
2038 if (sx->smtps)
2039 {
2040 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
2041 DEFER, FALSE);
2042 return ERROR;
2043 }
2044 #endif
2045
2046 /* Make a connection to the host if this isn't a continued delivery, and handle
2047 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2048 specially so they can be identified for retries. */
2049
2050 if (!continue_hostname)
2051 {
2052 if (sx->verify)
2053 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2054
2055 /* Get the actual port the connection will use, into sx->conn_args.host */
2056
2057 smtp_port_for_connect(sx->conn_args.host, sx->port);
2058
2059 #ifdef SUPPORT_DANE
2060 /* Do TLSA lookup for DANE */
2061 {
2062 tls_out.dane_verified = FALSE;
2063 tls_out.tlsa_usage = 0;
2064
2065 if (sx->conn_args.host->dnssec == DS_YES)
2066 {
2067 if( sx->dane_required
2068 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2069 )
2070 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2071 {
2072 case OK: sx->conn_args.dane = TRUE;
2073 ob->tls_tempfail_tryclear = FALSE;
2074 break;
2075 case FAIL_FORCED: break;
2076 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2077 string_sprintf("DANE error: tlsa lookup %s",
2078 rc_to_string(rc)),
2079 rc, FALSE);
2080 # ifndef DISABLE_EVENT
2081 (void) event_raise(sx->conn_args.tblock->event_action,
2082 US"dane:fail", sx->dane_required
2083 ? US"dane-required" : US"dnssec-invalid");
2084 # endif
2085 return rc;
2086 }
2087 }
2088 else if (sx->dane_required)
2089 {
2090 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2091 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2092 FAIL, FALSE);
2093 # ifndef DISABLE_EVENT
2094 (void) event_raise(sx->conn_args.tblock->event_action,
2095 US"dane:fail", US"dane-required");
2096 # endif
2097 return FAIL;
2098 }
2099 }
2100 #endif /*DANE*/
2101
2102 /* Make the TCP connection */
2103
2104 sx->cctx.tls_ctx = NULL;
2105 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2106 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2107
2108 #ifdef EXPERIMENTAL_PIPE_CONNECT
2109 if (verify_check_given_host(CUSS &ob->hosts_pipe_connect, sx->conn_args.host) == OK)
2110 {
2111 sx->early_pipe_ok = TRUE;
2112 if ( read_ehlo_cache_entry(sx)
2113 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2114 {
2115 DEBUG(D_transport) debug_printf("Using cached cleartext PIPE_CONNECT\n");
2116 sx->early_pipe_active = TRUE;
2117 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2118 }
2119 }
2120
2121 if (sx->early_pipe_active)
2122 sx->outblock.conn_args = &sx->conn_args;
2123 else
2124 #endif
2125 {
2126 if ((sx->cctx.sock = smtp_connect(&sx->conn_args, NULL)) < 0)
2127 {
2128 uschar * msg = NULL;
2129 if (sx->verify)
2130 {
2131 msg = US strerror(errno);
2132 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
2133 }
2134 set_errno_nohost(sx->addrlist,
2135 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2136 sx->verify ? msg : NULL,
2137 DEFER, FALSE);
2138 sx->send_quit = FALSE;
2139 return DEFER;
2140 }
2141 }
2142 /* Expand the greeting message while waiting for the initial response. (Makes
2143 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2144 delayed till here so that $sending_interface and $sending_port are set. */
2145 /*XXX early-pipe: they still will not be. Is there any way to find out what they
2146 will be? Somehow I doubt it. */
2147
2148 if (sx->helo_data)
2149 if (!(sx->helo_data = expand_string(sx->helo_data)))
2150 if (sx->verify)
2151 log_write(0, LOG_MAIN|LOG_PANIC,
2152 "<%s>: failed to expand transport's helo_data value for callout: %s",
2153 sx->addrlist->address, expand_string_message);
2154
2155 #ifdef SUPPORT_I18N
2156 if (sx->helo_data)
2157 {
2158 expand_string_message = NULL;
2159 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2160 &expand_string_message)),
2161 expand_string_message)
2162 if (sx->verify)
2163 log_write(0, LOG_MAIN|LOG_PANIC,
2164 "<%s>: failed to expand transport's helo_data value for callout: %s",
2165 sx->addrlist->address, expand_string_message);
2166 else
2167 sx->helo_data = NULL;
2168 }
2169 #endif
2170
2171 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2172 is nevertheless a reasonably clean way of programming this kind of logic,
2173 where you want to escape on any error. */
2174
2175 if (!sx->smtps)
2176 {
2177 #ifdef EXPERIMENTAL_PIPE_CONNECT
2178 if (sx->early_pipe_active)
2179 {
2180 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2181 sx->outblock.cmd_count = 1;
2182 }
2183 else
2184 #endif
2185 {
2186 #ifdef TCP_QUICKACK
2187 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2188 sizeof(off));
2189 #endif
2190 if (!smtp_reap_banner(sx))
2191 goto RESPONSE_FAILED;
2192 }
2193
2194 #ifndef DISABLE_EVENT
2195 {
2196 uschar * s;
2197 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2198 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2199 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer);
2200 if (s)
2201 {
2202 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2203 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2204 DEFER, FALSE);
2205 yield = DEFER;
2206 goto SEND_QUIT;
2207 }
2208 }
2209 #endif
2210
2211 /* Now check if the helo_data expansion went well, and sign off cleanly if
2212 it didn't. */
2213
2214 if (!sx->helo_data)
2215 {
2216 message = string_sprintf("failed to expand helo_data: %s",
2217 expand_string_message);
2218 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2219 yield = DEFER;
2220 goto SEND_QUIT;
2221 }
2222 }
2223
2224 /** Debugging without sending a message
2225 sx->addrlist->transport_return = DEFER;
2226 goto SEND_QUIT;
2227 **/
2228
2229 /* Errors that occur after this point follow an SMTP command, which is
2230 left in big_buffer by smtp_write_command() for use in error messages. */
2231
2232 smtp_command = big_buffer;
2233
2234 /* Tell the remote who we are...
2235
2236 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2237 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2238 greeting is of this form. The assumption was that the far end supports it
2239 properly... but experience shows that there are some that give 5xx responses,
2240 even though the banner includes "ESMTP" (there's a bloody-minded one that
2241 says "ESMTP not spoken here"). Cope with that case.
2242
2243 September 2000: Time has passed, and it seems reasonable now to always send
2244 EHLO at the start. It is also convenient to make the change while installing
2245 the TLS stuff.
2246
2247 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2248 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2249 would be no way to send out the mails, so there is now a host list
2250 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2251 PIPELINING problem as well. Maybe it can also be useful to cure other
2252 problems with broken servers.
2253
2254 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2255 Then somebody tried it with a Microsoft mailer... It seems that all other
2256 mailers use upper case for some reason (the RFC is quite clear about case
2257 independence) so, for peace of mind, I gave in. */
2258
2259 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2260
2261 /* Alas; be careful, since this goto is not an error-out, so conceivably
2262 we might set data between here and the target which we assume to exist
2263 and be usable. I can see this coming back to bite us. */
2264 #ifndef DISABLE_TLS
2265 if (sx->smtps)
2266 {
2267 smtp_peer_options |= OPTION_TLS;
2268 suppress_tls = FALSE;
2269 ob->tls_tempfail_tryclear = FALSE;
2270 smtp_command = US"SSL-on-connect";
2271 goto TLS_NEGOTIATE;
2272 }
2273 #endif
2274
2275 if (sx->esmtp)
2276 {
2277 if (smtp_write_command(sx,
2278 #ifdef EXPERIMENTAL_PIPE_CONNECT
2279 sx->early_pipe_active ? SCMD_BUFFER :
2280 #endif
2281 SCMD_FLUSH,
2282 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2283 goto SEND_FAILED;
2284 sx->esmtp_sent = TRUE;
2285
2286 #ifdef EXPERIMENTAL_PIPE_CONNECT
2287 if (sx->early_pipe_active)
2288 {
2289 sx->pending_EHLO = TRUE;
2290
2291 /* If we have too many authenticators to handle and might need to AUTH
2292 for this transport, pipeline no further as we will need the
2293 list of auth methods offered. Reap the banner and EHLO. */
2294
2295 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2296 && f.smtp_in_early_pipe_no_auth)
2297 {
2298 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2299 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2300 goto SEND_FAILED;
2301 if (sync_responses(sx, 2, 0) != 0)
2302 {
2303 HDEBUG(D_transport)
2304 debug_printf("failed reaping pipelined cmd responses\n");
2305 goto RESPONSE_FAILED;
2306 }
2307 sx->early_pipe_active = FALSE;
2308 }
2309 }
2310 else
2311 #endif
2312 if (!smtp_reap_ehlo(sx))
2313 goto RESPONSE_FAILED;
2314 }
2315 else
2316 DEBUG(D_transport)
2317 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2318
2319 #ifdef EXPERIMENTAL_PIPE_CONNECT
2320 if (!sx->early_pipe_active)
2321 #endif
2322 if (!sx->esmtp)
2323 {
2324 BOOL good_response;
2325 int n = sizeof(sx->buffer);
2326 uschar * rsp = sx->buffer;
2327
2328 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
2329 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
2330
2331 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2332 goto SEND_FAILED;
2333 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2334 #ifdef EXPERIMENTAL_DSN_INFO
2335 sx->helo_response = string_copy(rsp);
2336 #endif
2337 if (!good_response)
2338 {
2339 /* Handle special logging for a closed connection after HELO
2340 when had previously sent EHLO */
2341
2342 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2343 {
2344 errno = ERRNO_SMTPCLOSED;
2345 goto EHLOHELO_FAILED;
2346 }
2347 memmove(sx->buffer, rsp, Ustrlen(rsp));
2348 goto RESPONSE_FAILED;
2349 }
2350 }
2351
2352 if (sx->esmtp || sx->lmtp)
2353 {
2354 #ifdef EXPERIMENTAL_PIPE_CONNECT
2355 if (!sx->early_pipe_active)
2356 #endif
2357 {
2358 sx->peer_offered = ehlo_response(sx->buffer,
2359 OPTION_TLS /* others checked later */
2360 #ifdef EXPERIMENTAL_PIPE_CONNECT
2361 | (sx->early_pipe_ok
2362 ? OPTION_IGNQ
2363 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2364 #ifdef SUPPORT_I18N
2365 | OPTION_UTF8
2366 #endif
2367 | OPTION_EARLY_PIPE
2368 : 0
2369 )
2370 #endif
2371 );
2372 #ifdef EXPERIMENTAL_PIPE_CONNECT
2373 if (sx->early_pipe_ok)
2374 {
2375 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2376
2377 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2378 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2379 {
2380 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2381 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2382 write_ehlo_cache_entry(sx);
2383 }
2384 }
2385 #endif
2386 }
2387
2388 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2389
2390 #ifndef DISABLE_TLS
2391 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2392 #endif
2393 }
2394 }
2395
2396 /* For continuing deliveries down the same channel, having re-exec'd the socket
2397 is the standard input; for a socket held open from verify it is recorded
2398 in the cutthrough context block. Either way we don't need to redo EHLO here
2399 (but may need to do so for TLS - see below).
2400 Set up the pointer to where subsequent commands will be left, for
2401 error messages. Note that smtp_peer_options will have been
2402 set from the command line if they were set in the process that passed the
2403 connection on. */
2404
2405 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2406 as the continue goes via transport_pass_socket() and doublefork and exec.
2407 It does not wait. Unclear how we keep separate host's responses
2408 separate - we could match up by host ip+port as a bodge. */
2409
2410 else
2411 {
2412 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2413 {
2414 sx->cctx = cutthrough.cctx;
2415 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2416 }
2417 else
2418 {
2419 sx->cctx.sock = 0; /* stdin */
2420 sx->cctx.tls_ctx = NULL;
2421 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2422 }
2423 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2424 smtp_command = big_buffer;
2425 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2426
2427 /* For a continued connection with TLS being proxied for us, or a
2428 held-open verify connection with TLS, nothing more to do. */
2429
2430 if ( continue_proxy_cipher
2431 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2432 && cutthrough.is_tls)
2433 )
2434 {
2435 sx->peer_offered = smtp_peer_options;
2436 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2437 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2438 continue_proxy_cipher ? "proxied" : "verify conn with");
2439 return OK;
2440 }
2441 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2442 }
2443
2444 /* If TLS is available on this connection, whether continued or not, attempt to
2445 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2446 send another EHLO - the server may give a different answer in secure mode. We
2447 use a separate buffer for reading the response to STARTTLS so that if it is
2448 negative, the original EHLO data is available for subsequent analysis, should
2449 the client not be required to use TLS. If the response is bad, copy the buffer
2450 for error analysis. */
2451
2452 #ifndef DISABLE_TLS
2453 if ( smtp_peer_options & OPTION_TLS
2454 && !suppress_tls
2455 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2456 && ( !sx->verify
2457 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2458 ) )
2459 {
2460 uschar buffer2[4096];
2461
2462 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2463 goto SEND_FAILED;
2464
2465 #ifdef EXPERIMENTAL_PIPE_CONNECT
2466 /* If doing early-pipelining reap the banner and EHLO-response but leave
2467 the response for the STARTTLS we just sent alone. */
2468
2469 if (sx->early_pipe_active && sync_responses(sx, 2, 0) != 0)
2470 {
2471 HDEBUG(D_transport)
2472 debug_printf("failed reaping pipelined cmd responses\n");
2473 goto RESPONSE_FAILED;
2474 }
2475 #endif
2476
2477 /* If there is an I/O error, transmission of this message is deferred. If
2478 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2479 false, we also defer. However, if there is a temporary rejection of STARTTLS
2480 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2481 STARTTLS, we carry on. This means we will try to send the message in clear,
2482 unless the host is in hosts_require_tls (tested below). */
2483
2484 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2485 {
2486 if ( errno != 0
2487 || buffer2[0] == 0
2488 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2489 )
2490 {
2491 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2492 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2493 goto RESPONSE_FAILED;
2494 }
2495 }
2496
2497 /* STARTTLS accepted: try to negotiate a TLS session. */
2498
2499 else
2500 TLS_NEGOTIATE:
2501 {
2502 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2503 {
2504 /* TLS negotiation failed; give an error. From outside, this function may
2505 be called again to try in clear on a new connection, if the options permit
2506 it for this host. */
2507 #ifdef USE_GNUTLS
2508 GNUTLS_CONN_FAILED:
2509 #endif
2510 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2511
2512 # ifdef SUPPORT_DANE
2513 if (sx->conn_args.dane)
2514 {
2515 log_write(0, LOG_MAIN,
2516 "DANE attempt failed; TLS connection to %s [%s]: %s",
2517 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2518 # ifndef DISABLE_EVENT
2519 (void) event_raise(sx->conn_args.tblock->event_action,
2520 US"dane:fail", US"validation-failure"); /* could do with better detail */
2521 # endif
2522 }
2523 # endif
2524
2525 errno = ERRNO_TLSFAILURE;
2526 message = string_sprintf("TLS session: %s", tls_errstr);
2527 sx->send_quit = FALSE;
2528 goto TLS_FAILED;
2529 }
2530
2531 /* TLS session is set up */
2532
2533 smtp_peer_options_wrap = smtp_peer_options;
2534 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2535 if (addr->transport_return == PENDING_DEFER)
2536 {
2537 addr->cipher = tls_out.cipher;
2538 addr->ourcert = tls_out.ourcert;
2539 addr->peercert = tls_out.peercert;
2540 addr->peerdn = tls_out.peerdn;
2541 addr->ocsp = tls_out.ocsp;
2542 }
2543 }
2544 }
2545
2546 /* if smtps, we'll have smtp_command set to something else; always safe to
2547 reset it here. */
2548 smtp_command = big_buffer;
2549
2550 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2551 helo_data is null, we are dealing with a connection that was passed from
2552 another process, and so we won't have expanded helo_data above. We have to
2553 expand it here. $sending_ip_address and $sending_port are set up right at the
2554 start of the Exim process (in exim.c). */
2555
2556 if (tls_out.active.sock >= 0)
2557 {
2558 uschar * greeting_cmd;
2559
2560 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2561 {
2562 uschar *message = string_sprintf("failed to expand helo_data: %s",
2563 expand_string_message);
2564 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2565 yield = DEFER;
2566 goto SEND_QUIT;
2567 }
2568
2569 #ifdef EXPERIMENTAL_PIPE_CONNECT
2570 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2571 We're unlikely to get the group sent and delivered before the server sends its
2572 banner, but it's still worth sending as a group.
2573 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2574 the reverse. */
2575
2576 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2577 {
2578 sx->peer_offered = sx->ehlo_resp.crypted_features;
2579 if ((sx->early_pipe_active =
2580 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2581 DEBUG(D_transport) debug_printf("Using cached crypted PIPE_CONNECT\n");
2582 }
2583 #endif
2584
2585 /* For SMTPS we need to wait for the initial OK response. */
2586 if (sx->smtps)
2587 #ifdef EXPERIMENTAL_PIPE_CONNECT
2588 if (sx->early_pipe_active)
2589 {
2590 sx->pending_BANNER = TRUE;
2591 sx->outblock.cmd_count = 1;
2592 }
2593 else
2594 #endif
2595 if (!smtp_reap_banner(sx))
2596 goto RESPONSE_FAILED;
2597
2598 if (sx->lmtp)
2599 greeting_cmd = US"LHLO";
2600 else if (sx->esmtp)
2601 greeting_cmd = US"EHLO";
2602 else
2603 {
2604 greeting_cmd = US"HELO";
2605 DEBUG(D_transport)
2606 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2607 }
2608
2609 if (smtp_write_command(sx,
2610 #ifdef EXPERIMENTAL_PIPE_CONNECT
2611 sx->early_pipe_active ? SCMD_BUFFER :
2612 #endif
2613 SCMD_FLUSH,
2614 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2615 goto SEND_FAILED;
2616
2617 #ifdef EXPERIMENTAL_PIPE_CONNECT
2618 if (sx->early_pipe_active)
2619 sx->pending_EHLO = TRUE;
2620 else
2621 #endif
2622 {
2623 if (!smtp_reap_ehlo(sx))
2624 #ifdef USE_GNUTLS
2625 {
2626 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2627 cert late, under TLS1.3 - which means here; the first time we try to
2628 receive crypted data. Treat it as if it was a connect-time failure.
2629 See also the early-pipe equivalent... which will be hard; every call
2630 to sync_responses will need to check the result.
2631 It would be nicer to have GnuTLS check the cert during the handshake.
2632 Can it do that, with all the flexibility we need? */
2633
2634 tls_errstr = US"error on first read";
2635 goto GNUTLS_CONN_FAILED;
2636 }
2637 #else
2638 goto RESPONSE_FAILED;
2639 #endif
2640 smtp_peer_options = 0;
2641 }
2642 }
2643
2644 /* If the host is required to use a secure channel, ensure that we
2645 have one. */
2646
2647 else if ( sx->smtps
2648 # ifdef SUPPORT_DANE
2649 || sx->conn_args.dane
2650 # endif
2651 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2652 )
2653 {
2654 errno = ERRNO_TLSREQUIRED;
2655 message = string_sprintf("a TLS session is required, but %s",
2656 smtp_peer_options & OPTION_TLS
2657 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2658 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2659 if (sx->conn_args.dane)
2660 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2661 smtp_peer_options & OPTION_TLS
2662 ? US"validation-failure" /* could do with better detail */
2663 : US"starttls-not-supported");
2664 # endif
2665 goto TLS_FAILED;
2666 }
2667 #endif /*DISABLE_TLS*/
2668
2669 /* If TLS is active, we have just started it up and re-done the EHLO command,
2670 so its response needs to be analyzed. If TLS is not active and this is a
2671 continued session down a previously-used socket, we haven't just done EHLO, so
2672 we skip this. */
2673
2674 if (continue_hostname == NULL
2675 #ifndef DISABLE_TLS
2676 || tls_out.active.sock >= 0
2677 #endif
2678 )
2679 {
2680 if (sx->esmtp || sx->lmtp)
2681 {
2682 #ifdef EXPERIMENTAL_PIPE_CONNECT
2683 if (!sx->early_pipe_active)
2684 #endif
2685 {
2686 sx->peer_offered = ehlo_response(sx->buffer,
2687 0 /* no TLS */
2688 #ifdef EXPERIMENTAL_PIPE_CONNECT
2689 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2690 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2691 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2692 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2693
2694 #else
2695
2696 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2697 | OPTION_CHUNKING
2698 | OPTION_PRDR
2699 # ifdef SUPPORT_I18N
2700 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2701 /*XXX if we hand peercaps on to continued-conn processes,
2702 must not depend on this addr */
2703 # endif
2704 | OPTION_DSN
2705 | OPTION_PIPE
2706 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2707 #endif
2708 );
2709 #ifdef EXPERIMENTAL_PIPE_CONNECT
2710 if (tls_out.active.sock >= 0)
2711 sx->ehlo_resp.crypted_features = sx->peer_offered;
2712 #endif
2713 }
2714
2715 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2716 lmtp_ignore_quota option was set. */
2717
2718 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2719
2720 /* If the response to EHLO specified support for the SIZE parameter, note
2721 this, provided size_addition is non-negative. */
2722
2723 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2724
2725 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2726 the current host, esmtp will be false, so PIPELINING can never be used. If
2727 the current host matches hosts_avoid_pipelining, don't do it. */
2728
2729 if ( sx->peer_offered & OPTION_PIPE
2730 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2731 smtp_peer_options |= OPTION_PIPE;
2732
2733 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2734 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2735
2736 if ( sx->peer_offered & OPTION_CHUNKING
2737 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) != OK)
2738 sx->peer_offered &= ~OPTION_CHUNKING;
2739
2740 if (sx->peer_offered & OPTION_CHUNKING)
2741 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2742
2743 #ifndef DISABLE_PRDR
2744 if ( sx->peer_offered & OPTION_PRDR
2745 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) != OK)
2746 sx->peer_offered &= ~OPTION_PRDR;
2747
2748 if (sx->peer_offered & OPTION_PRDR)
2749 DEBUG(D_transport) debug_printf("PRDR usable\n");
2750 #endif
2751
2752 /* Note if the server supports DSN */
2753 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2754 DEBUG(D_transport) debug_printf("%susing DSN\n",
2755 sx->peer_offered & OPTION_DSN ? "" : "not ");
2756
2757 #ifdef EXPERIMENTAL_PIPE_CONNECT
2758 if ( sx->early_pipe_ok
2759 && !sx->early_pipe_active
2760 && tls_out.active.sock >= 0
2761 && smtp_peer_options & OPTION_PIPE
2762 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
2763 & OPTION_EARLY_PIPE)
2764 {
2765 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2766 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
2767 write_ehlo_cache_entry(sx);
2768 }
2769 #endif
2770
2771 /* Note if the response to EHLO specifies support for the AUTH extension.
2772 If it has, check that this host is one we want to authenticate to, and do
2773 the business. The host name and address must be available when the
2774 authenticator's client driver is running. */
2775
2776 switch (yield = smtp_auth(sx))
2777 {
2778 default: goto SEND_QUIT;
2779 case OK: break;
2780 case FAIL_SEND: goto SEND_FAILED;
2781 case FAIL: goto RESPONSE_FAILED;
2782 }
2783 }
2784 }
2785 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2786
2787 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2788 message-specific. */
2789
2790 sx->setting_up = FALSE;
2791
2792 #ifdef SUPPORT_I18N
2793 if (sx->addrlist->prop.utf8_msg)
2794 {
2795 uschar * s;
2796
2797 /* If the transport sets a downconversion mode it overrides any set by ACL
2798 for the message. */
2799
2800 if ((s = ob->utf8_downconvert))
2801 {
2802 if (!(s = expand_string(s)))
2803 {
2804 message = string_sprintf("failed to expand utf8_downconvert: %s",
2805 expand_string_message);
2806 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2807 yield = DEFER;
2808 goto SEND_QUIT;
2809 }
2810 switch (*s)
2811 {
2812 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
2813 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2814 break;
2815 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
2816 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2817 break;
2818 case '-': if (s[1] == '1')
2819 {
2820 sx->addrlist->prop.utf8_downcvt = FALSE;
2821 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
2822 }
2823 break;
2824 }
2825 }
2826
2827 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2828 && !sx->addrlist->prop.utf8_downcvt_maybe;
2829 DEBUG(D_transport) if (!sx->utf8_needed)
2830 debug_printf("utf8: %s downconvert\n",
2831 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2832 }
2833
2834 /* If this is an international message we need the host to speak SMTPUTF8 */
2835 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2836 {
2837 errno = ERRNO_UTF8_FWD;
2838 goto RESPONSE_FAILED;
2839 }
2840 #endif /*SUPPORT_I18N*/
2841
2842 return OK;
2843
2844
2845 {
2846 int code;
2847
2848 RESPONSE_FAILED:
2849 message = NULL;
2850 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
2851 sx->buffer, &code, &message, &pass_message);
2852 yield = DEFER;
2853 goto FAILED;
2854
2855 SEND_FAILED:
2856 code = '4';
2857 message = US string_sprintf("send() to %s [%s] failed: %s",
2858 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
2859 sx->send_quit = FALSE;
2860 yield = DEFER;
2861 goto FAILED;
2862
2863 EHLOHELO_FAILED:
2864 code = '4';
2865 message = string_sprintf("Remote host closed connection in response to %s"
2866 " (EHLO response was: %s)", smtp_command, sx->buffer);
2867 sx->send_quit = FALSE;
2868 yield = DEFER;
2869 goto FAILED;
2870
2871 /* This label is jumped to directly when a TLS negotiation has failed,
2872 or was not done for a host for which it is required. Values will be set
2873 in message and errno, and setting_up will always be true. Treat as
2874 a temporary error. */
2875
2876 #ifndef DISABLE_TLS
2877 TLS_FAILED:
2878 code = '4', yield = DEFER;
2879 goto FAILED;
2880 #endif
2881
2882 /* The failure happened while setting up the call; see if the failure was
2883 a 5xx response (this will either be on connection, or following HELO - a 5xx
2884 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2885 fail all addresses, as this host is never going to accept them. For other
2886 errors during setting up (timeouts or whatever), defer all addresses, and
2887 yield DEFER, so that the host is not tried again for a while.
2888
2889 XXX This peeking for another host feels like a layering violation. We want
2890 to note the host as unusable, but down here we shouldn't know if this was
2891 the last host to try for the addr(list). Perhaps the upper layer should be
2892 the one to do set_errno() ? The problem is that currently the addr is where
2893 errno etc. are stashed, but until we run out of hosts to try the errors are
2894 host-specific. Maybe we should enhance the host_item definition? */
2895
2896 FAILED:
2897 sx->ok = FALSE; /* For when reached by GOTO */
2898 set_errno(sx->addrlist, errno, message,
2899 sx->conn_args.host->next
2900 ? DEFER
2901 : code == '5'
2902 #ifdef SUPPORT_I18N
2903 || errno == ERRNO_UTF8_FWD
2904 #endif
2905 ? FAIL : DEFER,
2906 pass_message, sx->conn_args.host
2907 #ifdef EXPERIMENTAL_DSN_INFO
2908 , sx->smtp_greeting, sx->helo_response
2909 #endif
2910 );
2911 }
2912
2913
2914 SEND_QUIT:
2915
2916 if (sx->send_quit)
2917 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
2918
2919 #ifndef DISABLE_TLS
2920 if (sx->cctx.tls_ctx)
2921 {
2922 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
2923 sx->cctx.tls_ctx = NULL;
2924 }
2925 #endif
2926
2927 /* Close the socket, and return the appropriate value, first setting
2928 works because the NULL setting is passed back to the calling process, and
2929 remote_max_parallel is forced to 1 when delivering over an existing connection,
2930 */
2931
2932 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2933 if (sx->send_quit)
2934 {
2935 shutdown(sx->cctx.sock, SHUT_WR);
2936 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
2937 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
2938 i--; /* drain socket */
2939 sx->send_quit = FALSE;
2940 }
2941 (void)close(sx->cctx.sock);
2942 sx->cctx.sock = -1;
2943
2944 #ifndef DISABLE_EVENT
2945 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL);
2946 #endif
2947
2948 continue_transport = NULL;
2949 continue_hostname = NULL;
2950 return yield;
2951 }
2952
2953
2954
2955
2956 /* Create the string of options that will be appended to the MAIL FROM:
2957 in the connection context buffer */
2958
2959 static int
2960 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2961 {
2962 uschar * p = sx->buffer;
2963 address_item * addr;
2964 int address_count;
2965
2966 *p = 0;
2967
2968 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2969 send it, adding something to the message size to allow for imprecision
2970 and things that get added en route. Exim keeps the number of lines
2971 in a message, so we can give an accurate value for the original message, but we
2972 need some additional to handle added headers. (Double "." characters don't get
2973 included in the count.) */
2974
2975 if ( message_size > 0
2976 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
2977 {
2978 /*XXX problem here under spool_files_wireformat?
2979 Or just forget about lines? Or inflate by a fixed proportion? */
2980
2981 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
2982 while (*p) p++;
2983 }
2984
2985 #ifndef DISABLE_PRDR
2986 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
2987 request that */
2988
2989 sx->prdr_active = FALSE;
2990 if (sx->peer_offered & OPTION_PRDR)
2991 for (address_item * addr = addrlist; addr; addr = addr->next)
2992 if (addr->transport_return == PENDING_DEFER)
2993 {
2994 for (addr = addr->next; addr; addr = addr->next)
2995 if (addr->transport_return == PENDING_DEFER)
2996 { /* at least two recipients to send */
2997 sx->prdr_active = TRUE;
2998 sprintf(CS p, " PRDR"); p += 5;
2999 break;
3000 }
3001 break;
3002 }
3003 #endif
3004
3005 #ifdef SUPPORT_I18N
3006 /* If it supports internationalised messages, and this meesage need that,
3007 request it */
3008
3009 if ( sx->peer_offered & OPTION_UTF8
3010 && addrlist->prop.utf8_msg
3011 && !addrlist->prop.utf8_downcvt
3012 )
3013 Ustrcpy(p, " SMTPUTF8"), p += 9;
3014 #endif
3015
3016 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3017 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3018 addr && address_count < sx->max_rcpt;
3019 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3020 {
3021 address_count++;
3022 if (!(addr->dsn_flags & rf_dsnlasthop))
3023 {
3024 sx->dsn_all_lasthop = FALSE;
3025 break;
3026 }
3027 }
3028
3029 /* Add any DSN flags to the mail command */
3030
3031 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3032 {
3033 if (dsn_ret == dsn_ret_hdrs)
3034 { Ustrcpy(p, " RET=HDRS"); p += 9; }
3035 else if (dsn_ret == dsn_ret_full)
3036 { Ustrcpy(p, " RET=FULL"); p += 9; }
3037
3038 if (dsn_envid)
3039 {
3040 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3041 while (*p) p++;
3042 }
3043 }
3044
3045 /* If an authenticated_sender override has been specified for this transport
3046 instance, expand it. If the expansion is forced to fail, and there was already
3047 an authenticated_sender for this message, the original value will be used.
3048 Other expansion failures are serious. An empty result is ignored, but there is
3049 otherwise no check - this feature is expected to be used with LMTP and other
3050 cases where non-standard addresses (e.g. without domains) might be required. */
3051
3052 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->conn_args.ob))
3053 return ERROR;
3054
3055 return OK;
3056 }
3057
3058
3059 static void
3060 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3061 {
3062 uschar * p = sx->buffer;
3063 *p = 0;
3064
3065 /* Add any DSN flags to the rcpt command */
3066
3067 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3068 {
3069 if (addr->dsn_flags & rf_dsnflags)
3070 {
3071 BOOL first = TRUE;
3072
3073 Ustrcpy(p, " NOTIFY=");
3074 while (*p) p++;
3075 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3076 {
3077 if (!first) *p++ = ',';
3078 first = FALSE;
3079 Ustrcpy(p, rf_names[i]);
3080 while (*p) p++;
3081 }
3082 }
3083
3084 if (addr->dsn_orcpt)
3085 {
3086 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3087 addr->dsn_orcpt);
3088 while (*p) p++;
3089 }
3090 }
3091 }
3092
3093
3094
3095 /*
3096 Return:
3097 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3098 -1 MAIL response error
3099 -2 any non-MAIL read i/o error
3100 -3 non-MAIL response timeout
3101 -4 internal error; channel still usable
3102 -5 transmit failed
3103 */
3104
3105 int
3106 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3107 {
3108 address_item * addr;
3109 int address_count;
3110 int rc;
3111
3112 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3113 {
3114 *yield = ERROR;
3115 return -4;
3116 }
3117
3118 /* From here until we send the DATA command, we can make use of PIPELINING
3119 if the server host supports it. The code has to be able to check the responses
3120 at any point, for when the buffer fills up, so we write it totally generally.
3121 When PIPELINING is off, each command written reports that it has flushed the
3122 buffer. */
3123
3124 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3125
3126 {
3127 uschar * s = sx->from_addr;
3128 #ifdef SUPPORT_I18N
3129 uschar * errstr = NULL;
3130
3131 /* If we must downconvert, do the from-address here. Remember we had to
3132 for the to-addresses (done below), and also (ugly) for re-doing when building
3133 the delivery log line. */
3134
3135 if ( sx->addrlist->prop.utf8_msg
3136 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3137 )
3138 {
3139 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3140 {
3141 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
3142 *yield = ERROR;
3143 return -4;
3144 }
3145 setflag(sx->addrlist, af_utf8_downcvt);
3146 }
3147 #endif
3148
3149 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3150 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3151 }
3152
3153 mail_command = string_copy(big_buffer); /* Save for later error message */
3154
3155 switch(rc)
3156 {
3157 case -1: /* Transmission error */
3158 return -5;
3159
3160 case +1: /* Cmd was sent */
3161 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3162 (SOB sx->conn_args.ob)->command_timeout))
3163 {
3164 if (errno == 0 && sx->buffer[0] == '4')
3165 {
3166 errno = ERRNO_MAIL4XX;
3167 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3168 }
3169 return -1;
3170 }
3171 sx->pending_MAIL = FALSE;
3172 break;
3173
3174 /* otherwise zero: command queued for pipeline */
3175 }
3176
3177 /* Pass over all the relevant recipient addresses for this host, which are the
3178 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3179 several before we have to read the responses for those seen so far. This
3180 checking is done by a subroutine because it also needs to be done at the end.
3181 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3182 the next one if not all are sent.
3183
3184 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3185 last address because we want to abort if any recipients have any kind of
3186 problem, temporary or permanent. We know that all recipient addresses will have
3187 the PENDING_DEFER status, because only one attempt is ever made, and we know
3188 that max_rcpt will be large, so all addresses will be done at once.
3189
3190 For verify we flush the pipeline after any (the only) rcpt address. */
3191
3192 for (addr = sx->first_addr, address_count = 0;
3193 addr && address_count < sx->max_rcpt;
3194 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3195 {
3196 int count;
3197 BOOL no_flush;
3198 uschar * rcpt_addr;
3199
3200 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3201 ? dsn_support_yes : dsn_support_no;
3202
3203 address_count++;
3204 no_flush = pipelining_active && !sx->verify
3205 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3206
3207 build_rcptcmd_options(sx, addr);
3208
3209 /* Now send the RCPT command, and process outstanding responses when
3210 necessary. After a timeout on RCPT, we just end the function, leaving the
3211 yield as OK, because this error can often mean that there is a problem with
3212 just one address, so we don't want to delay the host. */
3213
3214 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3215
3216 #ifdef SUPPORT_I18N
3217 if ( testflag(sx->addrlist, af_utf8_downcvt)
3218 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3219 )
3220 {
3221 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3222 errno = ERRNO_EXPANDFAIL;
3223 return -5; /*XXX too harsh? */
3224 }
3225 #endif
3226
3227 count = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3228 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3229
3230 if (count < 0) return -5;
3231 if (count > 0)
3232 {
3233 switch(sync_responses(sx, count, 0))
3234 {
3235 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3236 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3237 break;
3238
3239 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3240 if (!sx->lmtp) /* can't tell about progress yet */
3241 sx->completed_addr = TRUE;
3242 case 0: /* No 2xx or 5xx, but no probs */
3243 break;
3244
3245 case -1: return -3; /* Timeout on RCPT */
3246 case -2: return -2; /* non-MAIL read i/o error */
3247 default: return -1; /* any MAIL error */
3248
3249 #ifdef EXPERIMENTAL_PIPE_CONNECT
3250 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3251 case -5: return -1; /* TLS first-read error */
3252 #endif
3253 }
3254 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
3255 }
3256 } /* Loop for next address */
3257
3258 sx->next_addr = addr;
3259 return 0;
3260 }
3261
3262
3263 #ifndef DISABLE_TLS
3264 /*****************************************************
3265 * Proxy TLS connection for another transport process *
3266 ******************************************************/
3267 /*
3268 Close the unused end of the pipe, fork once more, then use the given buffer
3269 as a staging area, and select on both the given fd and the TLS'd client-fd for
3270 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3271 Do blocking full-size writes, and reads under a timeout. Once both input
3272 channels are closed, exit the process.
3273
3274 Arguments:
3275 ct_ctx tls context
3276 buf space to use for buffering
3277 bufsiz size of buffer
3278 pfd pipe filedescriptor array; [0] is comms to proxied process
3279 timeout per-read timeout, seconds
3280 */
3281
3282 void
3283 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3284 int timeout)
3285 {
3286 fd_set rfds, efds;
3287 int max_fd = MAX(pfd[0], tls_out.active.sock) + 1;
3288 int rc, i;
3289
3290 close(pfd[1]);
3291 if ((rc = fork()))
3292 {
3293 DEBUG(D_transport) debug_printf("proxy-proc final-pid %d\n", rc);
3294 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3295 }
3296
3297 if (f.running_in_test_harness) millisleep(100); /* let parent debug out */
3298 set_process_info("proxying TLS connection for continued transport");
3299 FD_ZERO(&rfds);
3300 FD_SET(tls_out.active.sock, &rfds);
3301 FD_SET(pfd[0], &rfds);
3302
3303 for (int fd_bits = 3; fd_bits; )
3304 {
3305 time_t time_left = timeout;
3306 time_t time_start = time(NULL);
3307
3308 /* wait for data */
3309 efds = rfds;
3310 do
3311 {
3312 struct timeval tv = { time_left, 0 };
3313
3314 rc = select(max_fd,
3315 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
3316
3317 if (rc < 0 && errno == EINTR)
3318 if ((time_left -= time(NULL) - time_start) > 0) continue;
3319
3320 if (rc <= 0)
3321 {
3322 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3323 goto done;
3324 }
3325
3326 if (FD_ISSET(tls_out.active.sock, &efds) || FD_ISSET(pfd[0], &efds))
3327 {
3328 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3329 FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
3330 goto done;
3331 }
3332 }
3333 while (rc < 0 || !(FD_ISSET(tls_out.active.sock, &rfds) || FD_ISSET(pfd[0], &rfds)));
3334
3335 /* handle inbound data */
3336 if (FD_ISSET(tls_out.active.sock, &rfds))
3337 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0)
3338 {
3339 fd_bits &= ~1;
3340 FD_CLR(tls_out.active.sock, &rfds);
3341 shutdown(pfd[0], SHUT_WR);
3342 timeout = 5;
3343 }
3344 else
3345 {
3346 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3347 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3348 }
3349 else if (fd_bits & 1)
3350 FD_SET(tls_out.active.sock, &rfds);
3351
3352 /* handle outbound data */
3353 if (FD_ISSET(pfd[0], &rfds))
3354 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3355 {
3356 fd_bits = 0;
3357 tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3358 ct_ctx = NULL;
3359 }
3360 else
3361 {
3362 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3363 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3364 goto done;
3365 }
3366 else if (fd_bits & 2)
3367 FD_SET(pfd[0], &rfds);
3368 }
3369
3370 done:
3371 if (f.running_in_test_harness) millisleep(100); /* let logging complete */
3372 exim_exit(0, US"TLS proxy");
3373 }
3374 #endif
3375
3376
3377 /*************************************************
3378 * Deliver address list to given host *
3379 *************************************************/
3380
3381 /* If continue_hostname is not null, we get here only when continuing to
3382 deliver down an existing channel. The channel was passed as the standard
3383 input. TLS is never active on a passed channel; the previous process always
3384 closes it down before passing the connection on.
3385
3386 Otherwise, we have to make a connection to the remote host, and do the
3387 initial protocol exchange.
3388
3389 When running as an MUA wrapper, if the sender or any recipient is rejected,
3390 temporarily or permanently, we force failure for all recipients.
3391
3392 Arguments:
3393 addrlist chain of potential addresses to deliver; only those whose
3394 transport_return field is set to PENDING_DEFER are currently
3395 being processed; others should be skipped - they have either
3396 been delivered to an earlier host or IP address, or been
3397 failed by one of them.
3398 host host to deliver to
3399 host_af AF_INET or AF_INET6
3400 defport default TCP/IP port to use if host does not specify, in host
3401 byte order
3402 interface interface to bind to, or NULL
3403 tblock transport instance block
3404 message_defer set TRUE if yield is OK, but all addresses were deferred
3405 because of a non-recipient, non-host failure, that is, a
3406 4xx response to MAIL FROM, DATA, or ".". This is a defer
3407 that is specific to the message.
3408 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3409 a second attempt after TLS initialization fails
3410
3411 Returns: OK - the connection was made and the delivery attempted;
3412 the result for each address is in its data block.
3413 DEFER - the connection could not be made, or something failed
3414 while setting up the SMTP session, or there was a
3415 non-message-specific error, such as a timeout.
3416 ERROR - a filter command is specified for this transport,
3417 and there was a problem setting it up; OR helo_data
3418 or add_headers or authenticated_sender is specified
3419 for this transport, and the string failed to expand
3420 */
3421
3422 static int
3423 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3424 uschar *interface, transport_instance *tblock,
3425 BOOL *message_defer, BOOL suppress_tls)
3426 {
3427 smtp_transport_options_block * ob = SOB tblock->options_block;
3428 int yield = OK;
3429 int save_errno;
3430 int rc;
3431 struct timeval start_delivery_time;
3432
3433 BOOL pass_message = FALSE;
3434 uschar *message = NULL;
3435 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3436
3437 smtp_context sx;
3438
3439 gettimeofday(&start_delivery_time, NULL);
3440 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
3441 *message_defer = FALSE;
3442
3443 sx.addrlist = addrlist;
3444 sx.conn_args.host = host;
3445 sx.conn_args.host_af = host_af,
3446 sx.port = defport;
3447 sx.conn_args.interface = interface;
3448 sx.helo_data = NULL;
3449 sx.conn_args.tblock = tblock;
3450 sx.verify = FALSE;
3451 sx.sync_addr = sx.first_addr = addrlist;
3452
3453 /* Get the channel set up ready for a message (MAIL FROM being the next
3454 SMTP command to send */
3455
3456 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
3457 return rc;
3458
3459 /* If there is a filter command specified for this transport, we can now
3460 set it up. This cannot be done until the identify of the host is known. */
3461
3462 if (tblock->filter_command)
3463 {
3464 transport_filter_timeout = tblock->filter_timeout;
3465
3466 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3467 yield ERROR. */
3468
3469 if (!transport_set_up_command(&transport_filter_argv,
3470 tblock->filter_command, TRUE, DEFER, addrlist,
3471 string_sprintf("%.50s transport", tblock->name), NULL))
3472 {
3473 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3474 FALSE);
3475 yield = ERROR;
3476 goto SEND_QUIT;
3477 }
3478
3479 if ( transport_filter_argv
3480 && *transport_filter_argv
3481 && **transport_filter_argv
3482 && sx.peer_offered & OPTION_CHUNKING
3483 )
3484 {
3485 sx.peer_offered &= ~OPTION_CHUNKING;
3486 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3487 }
3488 }
3489
3490 /* For messages that have more than the maximum number of envelope recipients,
3491 we want to send several transactions down the same SMTP connection. (See
3492 comments in deliver.c as to how this reconciles, heuristically, with
3493 remote_max_parallel.) This optimization was added to Exim after the following
3494 code was already working. The simplest way to put it in without disturbing the
3495 code was to use a goto to jump back to this point when there is another
3496 transaction to handle. */
3497
3498 SEND_MESSAGE:
3499 sx.from_addr = return_path;
3500 sx.sync_addr = sx.first_addr;
3501 sx.ok = FALSE;
3502 sx.send_rset = TRUE;
3503 sx.completed_addr = FALSE;
3504
3505
3506 /* If we are a continued-connection-after-verify the MAIL and RCPT
3507 commands were already sent; do not re-send but do mark the addrs as
3508 having been accepted up to RCPT stage. A traditional cont-conn
3509 always has a sequence number greater than one. */
3510
3511 if (continue_hostname && continue_sequence == 1)
3512 {
3513 sx.peer_offered = smtp_peer_options;
3514 sx.pending_MAIL = FALSE;
3515 sx.ok = TRUE;
3516 sx.next_addr = NULL;
3517
3518 for (address_item * addr = addrlist; addr; addr = addr->next)
3519 addr->transport_return = PENDING_OK;
3520 }
3521 else
3522 {
3523 /* Initiate a message transfer. */
3524
3525 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
3526 {
3527 case 0: break;
3528 case -1: case -2: goto RESPONSE_FAILED;
3529 case -3: goto END_OFF;
3530 case -4: goto SEND_QUIT;
3531 default: goto SEND_FAILED;
3532 }
3533
3534 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3535 permanently or temporarily. We should have flushed and synced after the last
3536 RCPT. */
3537
3538 if (mua_wrapper)
3539 {
3540 address_item * a;
3541 unsigned cnt;
3542
3543 for (a = sx.first_addr, cnt = 0; a && cnt < sx.max_rcpt; a = a->next, cnt++)
3544 if (a->transport_return != PENDING_OK)
3545 {
3546 /*XXX could we find a better errno than 0 here? */
3547 set_errno_nohost(addrlist, 0, a->message, FAIL,
3548 testflag(a, af_pass_message));
3549 sx.ok = FALSE;
3550 break;
3551 }
3552 }
3553 }
3554
3555 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3556 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3557 have a good recipient buffered up if we are pipelining. We don't want to waste
3558 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3559 are pipelining. The responses are all handled by sync_responses().
3560 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3561 to send is. */
3562
3563 if ( !(sx.peer_offered & OPTION_CHUNKING)
3564 && (sx.ok || (pipelining_active && !mua_wrapper)))
3565 {
3566 int count = smtp_write_command(&sx, SCMD_FLUSH, "DATA\r\n");
3567
3568 if (count < 0) goto SEND_FAILED;
3569 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
3570 {
3571 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3572 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3573 break;
3574
3575 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3576 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3577 case 0: break; /* No 2xx or 5xx, but no probs */
3578
3579 case -1: goto END_OFF; /* Timeout on RCPT */
3580
3581 #ifdef EXPERIMENTAL_PIPE_CONNECT
3582 case -5: /* TLS first-read error */
3583 case -4: HDEBUG(D_transport)
3584 debug_printf("failed reaping pipelined cmd responses\n");
3585 #endif
3586 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3587 }
3588 pipelining_active = FALSE;
3589 data_command = string_copy(big_buffer); /* Save for later error message */
3590 }
3591
3592 /* If there were no good recipients (but otherwise there have been no
3593 problems), just set ok TRUE, since we have handled address-specific errors
3594 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3595 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3596 well as body. Set the appropriate timeout value to be used for each chunk.
3597 (Haven't been able to make it work using select() for writing yet.) */
3598
3599 if (!(sx.peer_offered & OPTION_CHUNKING) && !sx.ok)
3600 {
3601 /* Save the first address of the next batch. */
3602 sx.first_addr = sx.next_addr;
3603
3604 sx.ok = TRUE;
3605 }
3606 else
3607 {
3608 transport_ctx tctx = {
3609 .u = {.fd = sx.cctx.sock}, /*XXX will this need TLS info? */
3610 .tblock = tblock,
3611 .addr = addrlist,
3612 .check_string = US".",
3613 .escape_string = US"..", /* Escaping strings */
3614 .options =
3615 topt_use_crlf | topt_escape_headers
3616 | (tblock->body_only ? topt_no_headers : 0)
3617 | (tblock->headers_only ? topt_no_body : 0)
3618 | (tblock->return_path_add ? topt_add_return_path : 0)
3619 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3620 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3621 };
3622
3623 /* If using CHUNKING we need a callback from the generic transport
3624 support to us, for the sending of BDAT smtp commands and the reaping
3625 of responses. The callback needs a whole bunch of state so set up
3626 a transport-context structure to be passed around. */
3627
3628 if (sx.peer_offered & OPTION_CHUNKING)
3629 {
3630 tctx.check_string = tctx.escape_string = NULL;
3631 tctx.options |= topt_use_bdat;
3632 tctx.chunk_cb = smtp_chunk_cmd_callback;
3633 sx.pending_BDAT = FALSE;
3634 sx.good_RCPT = sx.ok;
3635 sx.cmd_count = 0;
3636 tctx.smtp_context = &sx;
3637 }
3638 else
3639 tctx.options |= topt_end_dot;
3640
3641 /* Save the first address of the next batch. */
3642 sx.first_addr = sx.next_addr;
3643
3644 /* Responses from CHUNKING commands go in buffer. Otherwise,
3645 there has not been a response. */
3646
3647 sx.buffer[0] = 0;
3648
3649 sigalrm_seen = FALSE;
3650 transport_write_timeout = ob->data_timeout;
3651 smtp_command = US"sending data block"; /* For error messages */
3652 DEBUG(D_transport|D_v)
3653 if (sx.peer_offered & OPTION_CHUNKING)
3654 debug_printf(" will write message using CHUNKING\n");
3655 else
3656 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3657 transport_count = 0;
3658
3659 #ifndef DISABLE_DKIM
3660 dkim_exim_sign_init();
3661 # ifdef EXPERIMENTAL_ARC
3662 {
3663 uschar * s = ob->arc_sign;
3664 if (s)
3665 {
3666 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
3667 {
3668 if (!f.expand_string_forcedfail)
3669 {
3670 message = US"failed to expand arc_sign";
3671 sx.ok = FALSE;
3672 goto SEND_FAILED;
3673 }
3674 }
3675 else if (*s)
3676 {
3677 /* Ask dkim code to hash the body for ARC */
3678 (void) arc_ams_setup_sign_bodyhash();
3679 ob->dkim.force_bodyhash = TRUE;
3680 }
3681 }
3682 }
3683 # endif
3684 sx.ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
3685 #else
3686 sx.ok = transport_write_message(&tctx, 0);
3687 #endif
3688
3689 /* transport_write_message() uses write() because it is called from other
3690 places to write to non-sockets. This means that under some OS (e.g. Solaris)
3691 it can exit with "Broken pipe" as its error. This really means that the
3692 socket got closed at the far end. */
3693
3694 transport_write_timeout = 0; /* for subsequent transports */
3695
3696 /* Failure can either be some kind of I/O disaster (including timeout),
3697 or the failure of a transport filter or the expansion of added headers.
3698 Or, when CHUNKING, it can be a protocol-detected failure. */
3699
3700 if (!sx.ok)
3701 if (message) goto SEND_FAILED;
3702 else goto RESPONSE_FAILED;
3703
3704 /* We used to send the terminating "." explicitly here, but because of
3705 buffering effects at both ends of TCP/IP connections, you don't gain
3706 anything by keeping it separate, so it might as well go in the final
3707 data buffer for efficiency. This is now done by setting the topt_end_dot
3708 flag above. */
3709
3710 smtp_command = US"end of data";
3711
3712 if (sx.peer_offered & OPTION_CHUNKING && sx.cmd_count > 1)
3713 {
3714 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
3715 switch(sync_responses(&sx, sx.cmd_count-1, 0))
3716 {
3717 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3718 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3719 break;
3720
3721 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3722 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3723 case 0: break; /* No 2xx or 5xx, but no probs */
3724
3725 case -1: goto END_OFF; /* Timeout on RCPT */
3726
3727 #ifdef EXPERIMENTAL_PIPE_CONNECT
3728 case -5: /* TLS first-read error */
3729 case -4: HDEBUG(D_transport)
3730 debug_printf("failed reaping pipelined cmd responses\n");
3731 #endif
3732 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3733 }
3734 }
3735
3736 #ifndef DISABLE_PRDR
3737 /* For PRDR we optionally get a partial-responses warning followed by the
3738 individual responses, before going on with the overall response. If we don't
3739 get the warning then deal with per non-PRDR. */
3740
3741 if(sx.prdr_active)
3742 {
3743 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '3', ob->final_timeout);
3744 if (!sx.ok && errno == 0) switch(sx.buffer[0])
3745 {
3746 case '2': sx.prdr_active = FALSE;
3747 sx.ok = TRUE;
3748 break;
3749 case '4': errno = ERRNO_DATA4XX;
3750 addrlist->more_errno |=
3751 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3752 break;
3753 }
3754 }
3755 else
3756 #endif
3757
3758 /* For non-PRDR SMTP, we now read a single response that applies to the
3759 whole message. If it is OK, then all the addresses have been delivered. */
3760
3761 if (!sx.lmtp)
3762 {
3763 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3764 ob->final_timeout);
3765 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
3766 {
3767 errno = ERRNO_DATA4XX;
3768 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3769 }
3770 }
3771
3772 /* For LMTP, we get back a response for every RCPT command that we sent;
3773 some may be accepted and some rejected. For those that get a response, their
3774 status is fixed; any that are accepted have been handed over, even if later
3775 responses crash - at least, that's how I read RFC 2033.
3776
3777 If all went well, mark the recipient addresses as completed, record which
3778 host/IPaddress they were delivered to, and cut out RSET when sending another
3779 message down the same channel. Write the completed addresses to the journal
3780 now so that they are recorded in case there is a crash of hardware or
3781 software before the spool gets updated. Also record the final SMTP
3782 confirmation if needed (for SMTP only). */
3783
3784 if (sx.ok)
3785 {
3786 int flag = '=';
3787 struct timeval delivery_time;
3788 int len;
3789 uschar * conf = NULL;
3790
3791 timesince(&delivery_time, &start_delivery_time);
3792 sx.send_rset = FALSE;
3793 pipelining_active = FALSE;
3794
3795 /* Set up confirmation if needed - applies only to SMTP */
3796
3797 if (
3798 #ifdef DISABLE_EVENT
3799 LOGGING(smtp_confirmation) &&
3800 #endif
3801 !sx.lmtp
3802 )
3803 {
3804 const uschar *s = string_printing(sx.buffer);
3805 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3806 conf = (s == sx.buffer)? US string_copy(s) : US s;
3807 }
3808
3809 /* Process all transported addresses - for LMTP or PRDR, read a status for
3810 each one. */
3811
3812 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3813 {
3814 if (addr->transport_return != PENDING_OK) continue;
3815
3816 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3817 remaining addresses. Otherwise, it's a return code for just the one
3818 address. For temporary errors, add a retry item for the address so that
3819 it doesn't get tried again too soon. */
3820
3821 #ifndef DISABLE_PRDR
3822 if (sx.lmtp || sx.prdr_active)
3823 #else
3824 if (sx.lmtp)
3825 #endif
3826 {
3827 if (!smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3828 ob->final_timeout))
3829 {
3830 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3831 addr->message = string_sprintf(
3832 #ifndef DISABLE_PRDR
3833 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3834 #else
3835 "LMTP error after %s: %s",
3836 #endif
3837 data_command, string_printing(sx.buffer));
3838 setflag(addr, af_pass_message); /* Allow message to go to user */
3839 if (sx.buffer[0] == '5')
3840 addr->transport_return = FAIL;
3841 else
3842 {
3843 errno = ERRNO_DATA4XX;
3844 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3845 addr->transport_return = DEFER;
3846 #ifndef DISABLE_PRDR
3847 if (!sx.prdr_active)
3848 #endif
3849 retry_add_item(addr, addr->address_retry_key, 0);
3850 }
3851 continue;
3852 }
3853 sx.completed_addr = TRUE; /* NOW we can set this flag */
3854 if (LOGGING(smtp_confirmation))
3855 {
3856 const uschar *s = string_printing(sx.buffer);
3857 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3858 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3859 }
3860 }
3861
3862 /* SMTP, or success return from LMTP for this address. Pass back the
3863 actual host that was used. */
3864
3865 addr->transport_return = OK;
3866 addr->more_errno = delivery_time.tv_sec;
3867 addr->delivery_usec = delivery_time.tv_usec;
3868 addr->host_used = host;
3869 addr->special_action = flag;
3870 addr->message = conf;
3871
3872 if (tcp_out_fastopen)
3873 {
3874 setflag(addr, af_tcp_fastopen_conn);
3875 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
3876 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
3877 }
3878 if (sx.pipelining_used) setflag(addr, af_pipelining);
3879 #ifdef EXPERIMENTAL_PIPE_CONNECT
3880 if (sx.early_pipe_active) setflag(addr, af_early_pipe);
3881 #endif
3882 #ifndef DISABLE_PRDR
3883 if (sx.prdr_active) setflag(addr, af_prdr_used);
3884 #endif
3885 if (sx.peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
3886 flag = '-';
3887
3888 #ifndef DISABLE_PRDR
3889 if (!sx.prdr_active)
3890 #endif
3891 {
3892 /* Update the journal. For homonymic addresses, use the base address plus
3893 the transport name. See lots of comments in deliver.c about the reasons
3894 for the complications when homonyms are involved. Just carry on after
3895 write error, as it may prove possible to update the spool file later. */
3896
3897 if (testflag(addr, af_homonym))
3898 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3899 else
3900 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3901
3902 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3903 len = Ustrlen(CS sx.buffer);
3904 if (write(journal_fd, sx.buffer, len) != len)
3905 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3906 "%s: %s", sx.buffer, strerror(errno));
3907 }
3908 }
3909
3910 #ifndef DISABLE_PRDR
3911 if (sx.prdr_active)
3912 {
3913 const uschar * overall_message;
3914
3915 /* PRDR - get the final, overall response. For any non-success
3916 upgrade all the address statuses. */
3917
3918 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3919 ob->final_timeout);
3920 if (!sx.ok)
3921 {
3922 if(errno == 0 && sx.buffer[0] == '4')
3923 {
3924 errno = ERRNO_DATA4XX;
3925 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3926 }
3927 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3928 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3929 addr->transport_return = PENDING_OK; /* allow set_errno action */
3930 goto RESPONSE_FAILED;
3931 }
3932
3933 /* Append the overall response to the individual PRDR response for logging
3934 and update the journal, or setup retry. */
3935
3936 overall_message = string_printing(sx.buffer);
3937 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3938 if (addr->transport_return == OK)
3939 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
3940
3941 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3942 if (addr->transport_return == OK)
3943 {
3944 if (testflag(addr, af_homonym))
3945 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3946 else
3947 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3948
3949 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3950 len = Ustrlen(CS sx.buffer);
3951 if (write(journal_fd, sx.buffer, len) != len)
3952 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3953 "%s: %s", sx.buffer, strerror(errno));
3954 }
3955 else if (addr->transport_return == DEFER)
3956 retry_add_item(addr, addr->address_retry_key, -2);
3957 }
3958 #endif
3959
3960 /* Ensure the journal file is pushed out to disk. */
3961
3962 if (EXIMfsync(journal_fd) < 0)
3963 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3964 strerror(errno));
3965 }
3966 }
3967
3968
3969 /* Handle general (not specific to one address) failures here. The value of ok
3970 is used to skip over this code on the falling through case. A timeout causes a
3971 deferral. Other errors may defer or fail according to the response code, and
3972 may set up a special errno value, e.g. after connection chopped, which is
3973 assumed if errno == 0 and there is no text in the buffer. If control reaches
3974 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3975 the problem is not related to this specific message. */
3976
3977 if (!sx.ok)
3978 {
3979 int code, set_rc;
3980 uschar * set_message;
3981
3982 RESPONSE_FAILED:
3983 {
3984 save_errno = errno;
3985 message = NULL;
3986 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3987 sx.buffer, &code, &message, &pass_message);
3988 goto FAILED;
3989 }
3990
3991 SEND_FAILED:
3992 {
3993 save_errno = errno;
3994 code = '4';
3995 message = string_sprintf("send() to %s [%s] failed: %s",
3996 host->name, host->address, message ? message : US strerror(save_errno));
3997 sx.send_quit = FALSE;
3998 goto FAILED;
3999 }
4000
4001 FAILED:
4002 {
4003 BOOL message_error;
4004
4005 sx.ok = FALSE; /* For when reached by GOTO */
4006 set_message = message;
4007
4008 /* We want to handle timeouts after MAIL or "." and loss of connection after
4009 "." specially. They can indicate a problem with the sender address or with
4010 the contents of the message rather than a real error on the connection. These
4011 cases are treated in the same way as a 4xx response. This next bit of code
4012 does the classification. */
4013
4014 switch(save_errno)
4015 {
4016 case 0:
4017 case ERRNO_MAIL4XX:
4018 case ERRNO_DATA4XX:
4019 message_error = TRUE;
4020 break;
4021
4022 case ETIMEDOUT:
4023 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4024 Ustrncmp(smtp_command,"end ",4) == 0;
4025 break;
4026
4027 case ERRNO_SMTPCLOSED:
4028 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4029 break;
4030
4031 default:
4032 message_error = FALSE;
4033 break;
4034 }
4035
4036 /* Handle the cases that are treated as message errors. These are:
4037
4038 (a) negative response or timeout after MAIL
4039 (b) negative response after DATA
4040 (c) negative response or timeout or dropped connection after "."
4041 (d) utf8 support required and not offered
4042
4043 It won't be a negative response or timeout after RCPT, as that is dealt
4044 with separately above. The action in all cases is to set an appropriate
4045 error code for all the addresses, but to leave yield set to OK because the
4046 host itself has not failed. Of course, it might in practice have failed
4047 when we've had a timeout, but if so, we'll discover that at the next
4048 delivery attempt. For a temporary error, set the message_defer flag, and
4049 write to the logs for information if this is not the last host. The error
4050 for the last host will be logged as part of the address's log line. */
4051
4052 if (message_error)
4053 {
4054 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4055
4056 /* If there's an errno, the message contains just the identity of
4057 the host. */
4058
4059 if (code == '5')
4060 set_rc = FAIL;
4061 else /* Anything other than 5 is treated as temporary */
4062 {
4063 set_rc = DEFER;
4064 if (save_errno > 0)
4065 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4066
4067 write_logs(host, message, sx.first_addr ? sx.first_addr->basic_errno : 0);
4068
4069 *message_defer = TRUE;
4070 }
4071 }
4072
4073 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4074 ".", or some other transportation error. We defer all addresses and yield
4075 DEFER, except for the case of failed add_headers expansion, or a transport
4076 filter failure, when the yield should be ERROR, to stop it trying other
4077 hosts. */
4078
4079 else
4080 {
4081 #ifdef EXPERIMENTAL_PIPE_CONNECT
4082 /* If we were early-pipelinng and the actual EHLO response did not match
4083 the cached value we assumed, we could have detected it and passed a
4084 custom errno through to here. It would be nice to RSET and retry right
4085 away, but to reliably do that we eould need an extra synch point before
4086 we committed to data and that would discard half the gained roundrips.
4087 Or we could summarily drop the TCP connection. but that is also ugly.
4088 Instead, we ignore the possibility (having freshened the cache) and rely
4089 on the server telling us with a nonmessage error if we have tried to
4090 do something it no longer supports. */
4091 #endif
4092 set_rc = DEFER;
4093 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4094 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4095 }
4096 }
4097
4098 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
4099 #ifdef EXPERIMENTAL_DSN_INFO
4100 , sx.smtp_greeting, sx.helo_response
4101 #endif
4102 );
4103 }
4104
4105
4106 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4107 SMTP session tidily. However, if there were too many addresses to send in one
4108 message (indicated by first_addr being non-NULL) we want to carry on with the
4109 rest of them. Also, it is desirable to send more than one message down the SMTP
4110 connection if there are several waiting, provided we haven't already sent so
4111 many as to hit the configured limit. The function transport_check_waiting looks
4112 for a waiting message and returns its id. Then transport_pass_socket tries to
4113 set up a continued delivery by passing the socket on to another process. The
4114 variable send_rset is FALSE if a message has just been successfully transferred.
4115
4116 If we are already sending down a continued channel, there may be further
4117 addresses not yet delivered that are aimed at the same host, but which have not
4118 been passed in this run of the transport. In this case, continue_more will be
4119 true, and all we should do is send RSET if necessary, and return, leaving the
4120 channel open.
4121
4122 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4123 do not want to continue with other messages down the same channel, because that
4124 can lead to looping between two or more messages, all with the same,
4125 temporarily failing address(es). [The retry information isn't updated yet, so
4126 new processes keep on trying.] We probably also don't want to try more of this
4127 message's addresses either.
4128
4129 If we have started a TLS session, we have to end it before passing the
4130 connection to a new process. However, not all servers can handle this (Exim
4131 can), so we do not pass such a connection on if the host matches
4132 hosts_nopass_tls. */
4133
4134 DEBUG(D_transport)
4135 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4136 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
4137 sx.send_rset, f.continue_more, yield, sx.first_addr ? "not " : "");
4138
4139 if (sx.completed_addr && sx.ok && sx.send_quit)
4140 {
4141 BOOL more;
4142 smtp_compare_t t_compare;
4143
4144 t_compare.tblock = tblock;
4145 t_compare.current_sender_address = sender_address;
4146
4147 if ( sx.first_addr != NULL
4148 || f.continue_more
4149 || (
4150 #ifndef DISABLE_TLS
4151 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4152 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4153 )
4154 &&
4155 #endif
4156 transport_check_waiting(tblock->name, host->name,
4157 tblock->connection_max_messages, new_message_id, &more,
4158 (oicf)smtp_are_same_identities, (void*)&t_compare)
4159 ) )
4160 {
4161 uschar *msg;
4162 BOOL pass_message;
4163
4164 if (sx.send_rset)
4165 if (! (sx.ok = smtp_write_command(&sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4166 {
4167 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
4168 host->address, strerror(errno));
4169 sx.send_quit = FALSE;
4170 }
4171 else if (! (sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer),
4172 '2', ob->command_timeout)))
4173 {
4174 int code;
4175 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
4176 &pass_message);
4177 if (!sx.send_quit)
4178 {
4179 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4180 host->name, host->address, msg);
4181 }
4182 }
4183
4184 /* Either RSET was not needed, or it succeeded */
4185
4186 if (sx.ok)
4187 {
4188 #ifndef DISABLE_TLS
4189 int pfd[2];
4190 #endif
4191 int socket_fd = sx.cctx.sock;
4192
4193
4194 if (sx.first_addr != NULL) /* More addresses still to be sent */
4195 { /* in this run of the transport */
4196 continue_sequence++; /* Causes * in logging */
4197 goto SEND_MESSAGE;
4198 }
4199
4200 /* Unless caller said it already has more messages listed for this host,
4201 pass the connection on to a new Exim process (below, the call to
4202 transport_pass_socket). If the caller has more ready, just return with
4203 the connection still open. */
4204
4205 #ifndef DISABLE_TLS
4206 if (tls_out.active.sock >= 0)
4207 if ( f.continue_more
4208 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4209 {
4210 /* Before passing the socket on, or returning to caller with it still
4211 open, we must shut down TLS. Not all MTAs allow for the continuation
4212 of the SMTP session when TLS is shut down. We test for this by sending
4213 a new EHLO. If we don't get a good response, we don't attempt to pass
4214 the socket on. */
4215
4216 tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4217 sx.cctx.tls_ctx = NULL;
4218 smtp_peer_options = smtp_peer_options_wrap;
4219 sx.ok = !sx.smtps
4220 && smtp_write_command(&sx, SCMD_FLUSH, "EHLO %s\r\n", sx.helo_data)
4221 >= 0
4222 && smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer),
4223 '2', ob->command_timeout);
4224
4225 if (sx.ok && f.continue_more)
4226 return yield; /* More addresses for another run */
4227 }
4228 else
4229 {
4230 /* Set up a pipe for proxying TLS for the new transport process */
4231
4232 smtp_peer_options |= OPTION_TLS;
4233 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4234 socket_fd = pfd[1];
4235 else
4236 set_errno(sx.first_addr, errno, US"internal allocation problem",
4237 DEFER, FALSE, host
4238 # ifdef EXPERIMENTAL_DSN_INFO
4239 , sx.smtp_greeting, sx.helo_response
4240 # endif
4241 );
4242 }
4243 else
4244 #endif
4245 if (f.continue_more)
4246 return yield; /* More addresses for another run */
4247
4248 /* If the socket is successfully passed, we mustn't send QUIT (or
4249 indeed anything!) from here. */
4250
4251 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4252 propagate it from the initial
4253 */
4254 if (sx.ok && transport_pass_socket(tblock->name, host->name,
4255 host->address, new_message_id, socket_fd))
4256 {
4257 sx.send_quit = FALSE;
4258
4259 /* We have passed the client socket to a fresh transport process.
4260 If TLS is still active, we need to proxy it for the transport we
4261 just passed the baton to. Fork a child to to do it, and return to
4262 get logging done asap. Which way to place the work makes assumptions
4263 about post-fork prioritisation which may not hold on all platforms. */
4264 #ifndef DISABLE_TLS
4265 if (tls_out.active.sock >= 0)
4266 {
4267 int pid = fork();
4268 if (pid == 0) /* child; fork again to disconnect totally */
4269 {
4270 if (f.running_in_test_harness) millisleep(100); /* let parent debug out */
4271 /* does not return */
4272 smtp_proxy_tls(sx.cctx.tls_ctx, sx.buffer, sizeof(sx.buffer), pfd,
4273 ob->command_timeout);
4274 }
4275
4276 if (pid > 0) /* parent */
4277 {
4278 DEBUG(D_transport) debug_printf("proxy-proc inter-pid %d\n", pid);
4279 close(pfd[0]);
4280 /* tidy the inter-proc to disconn the proxy proc */
4281 waitpid(pid, NULL, 0);
4282 tls_close(sx.cctx.tls_ctx, TLS_NO_SHUTDOWN);
4283 sx.cctx.tls_ctx = NULL;
4284 (void)close(sx.cctx.sock);
4285 sx.cctx.sock = -1;
4286 continue_transport = NULL;
4287 continue_hostname = NULL;
4288 return yield;
4289 }
4290 log_write(0, LOG_PANIC_DIE, "fork failed");
4291 }
4292 #endif
4293 }
4294 }
4295
4296 /* If RSET failed and there are addresses left, they get deferred. */
4297 else
4298 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
4299 #ifdef EXPERIMENTAL_DSN_INFO
4300 , sx.smtp_greeting, sx.helo_response
4301 #endif
4302 );
4303 }
4304 }
4305
4306 /* End off tidily with QUIT unless the connection has died or the socket has
4307 been passed to another process. There has been discussion on the net about what
4308 to do after sending QUIT. The wording of the RFC suggests that it is necessary
4309 to wait for a response, but on the other hand, there isn't anything one can do
4310 with an error response, other than log it. Exim used to do that. However,
4311 further discussion suggested that it is positively advantageous not to wait for
4312 the response, but to close the session immediately. This is supposed to move
4313 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
4314 load from the server. (Hosts that are both servers and clients may not see much
4315 difference, of course.) Further discussion indicated that this was safe to do
4316 on Unix systems which have decent implementations of TCP/IP that leave the
4317 connection around for a while (TIME_WAIT) after the application has gone away.
4318 This enables the response sent by the server to be properly ACKed rather than
4319 timed out, as can happen on broken TCP/IP implementations on other OS.
4320
4321 This change is being made on 31-Jul-98. After over a year of trouble-free
4322 operation, the old commented-out code was removed on 17-Sep-99. */
4323
4324 SEND_QUIT:
4325 #ifdef TCP_CORK
4326 (void) setsockopt(sx.cctx.sock, IPPROTO_TCP, TCP_CORK, US &on, sizeof(on));
4327 #endif
4328 if (sx.send_quit) (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4329
4330 END_OFF:
4331
4332 #ifndef DISABLE_TLS
4333 tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
4334 sx.cctx.tls_ctx = NULL;
4335 #endif
4336
4337 /* Close the socket, and return the appropriate value, first setting
4338 works because the NULL setting is passed back to the calling process, and
4339 remote_max_parallel is forced to 1 when delivering over an existing connection,
4340
4341 If all went well and continue_more is set, we shouldn't actually get here if
4342 there are further addresses, as the return above will be taken. However,
4343 writing RSET might have failed, or there may be other addresses whose hosts are
4344 specified in the transports, and therefore not visible at top level, in which
4345 case continue_more won't get set. */
4346
4347 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4348 if (sx.send_quit)
4349 {
4350 shutdown(sx.cctx.sock, SHUT_WR);
4351 millisleep(f.running_in_test_harness ? 200 : 20);
4352 if (fcntl(sx.cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4353 for (int i = 16; read(sx.cctx.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && i > 0;)
4354 i--; /* drain socket */
4355 }
4356 (void)close(sx.cctx.sock);
4357
4358 #ifndef DISABLE_EVENT
4359 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
4360 #endif
4361
4362 continue_transport = NULL;
4363 continue_hostname = NULL;
4364 return yield;
4365 }
4366
4367
4368
4369
4370 /*************************************************
4371 * Closedown entry point *
4372 *************************************************/
4373
4374 /* This function is called when exim is passed an open smtp channel
4375 from another incarnation, but the message which it has been asked
4376 to deliver no longer exists. The channel is on stdin.
4377
4378 We might do fancy things like looking for another message to send down
4379 the channel, but if the one we sought has gone, it has probably been
4380 delivered by some other process that itself will seek further messages,
4381 so just close down our connection.
4382
4383 Argument: pointer to the transport instance block
4384 Returns: nothing
4385 */
4386
4387 void
4388 smtp_transport_closedown(transport_instance *tblock)
4389 {
4390 smtp_transport_options_block * ob = SOB tblock->options_block;
4391 client_conn_ctx cctx;
4392 smtp_context sx;
4393 uschar buffer[256];
4394 uschar inbuffer[4096];
4395 uschar outbuffer[16];
4396
4397 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4398 cctx.sock = fileno(stdin);
4399 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4400
4401 sx.inblock.cctx = &cctx;
4402 sx.inblock.buffer = inbuffer;
4403 sx.inblock.buffersize = sizeof(inbuffer);
4404 sx.inblock.ptr = inbuffer;
4405 sx.inblock.ptrend = inbuffer;
4406
4407 sx.outblock.cctx = &cctx;
4408 sx.outblock.buffersize = sizeof(outbuffer);
4409 sx.outblock.buffer = outbuffer;
4410 sx.outblock.ptr = outbuffer;
4411 sx.outblock.cmd_count = 0;
4412 sx.outblock.authenticating = FALSE;
4413
4414 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4415 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
4416 (void)close(cctx.sock);
4417 }
4418
4419
4420
4421 /*************************************************
4422 * Prepare addresses for delivery *
4423 *************************************************/
4424
4425 /* This function is called to flush out error settings from previous delivery
4426 attempts to other hosts. It also records whether we got here via an MX record
4427 or not in the more_errno field of the address. We are interested only in
4428 addresses that are still marked DEFER - others may have got delivered to a
4429 previously considered IP address. Set their status to PENDING_DEFER to indicate
4430 which ones are relevant this time.
4431
4432 Arguments:
4433 addrlist the list of addresses
4434 host the host we are delivering to
4435
4436 Returns: the first address for this delivery
4437 */
4438
4439 static address_item *
4440 prepare_addresses(address_item *addrlist, host_item *host)
4441 {
4442 address_item *first_addr = NULL;
4443 for (address_item * addr = addrlist; addr; addr = addr->next)
4444 if (addr->transport_return == DEFER)
4445 {
4446 if (!first_addr) first_addr = addr;
4447 addr->transport_return = PENDING_DEFER;
4448 addr->basic_errno = 0;
4449 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
4450 addr->message = NULL;
4451 #ifndef DISABLE_TLS
4452 addr->cipher = NULL;
4453 addr->ourcert = NULL;
4454 addr->peercert = NULL;
4455 addr->peerdn = NULL;
4456 addr->ocsp = OCSP_NOT_REQ;
4457 #endif
4458 #ifdef EXPERIMENTAL_DSN_INFO
4459 addr->smtp_greeting = NULL;
4460 addr->helo_response = NULL;
4461 #endif
4462 }
4463 return first_addr;
4464 }
4465
4466
4467
4468 /*************************************************
4469 * Main entry point *
4470 *************************************************/
4471
4472 /* See local README for interface details. As this is a remote transport, it is
4473 given a chain of addresses to be delivered in one connection, if possible. It
4474 always returns TRUE, indicating that each address has its own independent
4475 status set, except if there is a setting up problem, in which case it returns
4476 FALSE. */
4477
4478 BOOL
4479 smtp_transport_entry(
4480 transport_instance *tblock, /* data for this instantiation */
4481 address_item *addrlist) /* addresses we are working on */
4482 {
4483 int defport;
4484 int hosts_defer = 0;
4485 int hosts_fail = 0;
4486 int hosts_looked_up = 0;
4487 int hosts_retry = 0;
4488 int hosts_serial = 0;
4489 int hosts_total = 0;
4490 int total_hosts_tried = 0;
4491 BOOL expired = TRUE;
4492 uschar *expanded_hosts = NULL;
4493 uschar *pistring;
4494 uschar *tid = string_sprintf("%s transport", tblock->name);
4495 smtp_transport_options_block *ob = SOB tblock->options_block;
4496 host_item *hostlist = addrlist->host_list;
4497 host_item *host = NULL;
4498
4499 DEBUG(D_transport)
4500 {
4501 debug_printf("%s transport entered\n", tblock->name);
4502 for (address_item * addr = addrlist; addr; addr = addr->next)
4503 debug_printf(" %s\n", addr->address);
4504 if (hostlist)
4505 {
4506 debug_printf("hostlist:\n");
4507 for (host_item * host = hostlist; host; host = host->next)
4508 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
4509 }
4510 if (continue_hostname)
4511 debug_printf("already connected to %s [%s] (on fd %d)\n",
4512 continue_hostname, continue_host_address,
4513 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
4514 }
4515
4516 /* Set the flag requesting that these hosts be added to the waiting
4517 database if the delivery fails temporarily or if we are running with
4518 queue_smtp or a 2-stage queue run. This gets unset for certain
4519 kinds of error, typically those that are specific to the message. */
4520
4521 update_waiting = TRUE;
4522
4523 /* If a host list is not defined for the addresses - they must all have the
4524 same one in order to be passed to a single transport - or if the transport has
4525 a host list with hosts_override set, use the host list supplied with the
4526 transport. It is an error for this not to exist. */
4527
4528 if (!hostlist || (ob->hosts_override && ob->hosts))
4529 {
4530 if (!ob->hosts)
4531 {
4532 addrlist->message = string_sprintf("%s transport called with no hosts set",
4533 tblock->name);
4534 addrlist->transport_return = PANIC;
4535 return FALSE; /* Only top address has status */
4536 }
4537
4538 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
4539 ob->hosts);
4540
4541 /* If the transport's host list contains no '$' characters, and we are not
4542 randomizing, it is fixed and therefore a chain of hosts can be built once
4543 and for all, and remembered for subsequent use by other calls to this
4544 transport. If, on the other hand, the host list does contain '$', or we are
4545 randomizing its order, we have to rebuild it each time. In the fixed case,
4546 as the hosts string will never be used again, it doesn't matter that we
4547 replace all the : characters with zeros. */
4548
4549 if (!ob->hostlist)
4550 {
4551 uschar *s = ob->hosts;
4552
4553 if (Ustrchr(s, '$') != NULL)
4554 {
4555 if (!(expanded_hosts = expand_string(s)))
4556 {
4557 addrlist->message = string_sprintf("failed to expand list of hosts "
4558 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
4559 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
4560 return FALSE; /* Only top address has status */
4561 }
4562 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
4563 "\"%s\"\n", s, expanded_hosts);
4564 s = expanded_hosts;
4565 }
4566 else
4567 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
4568
4569 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
4570
4571 /* Check that the expansion yielded something useful. */
4572 if (!hostlist)
4573 {
4574 addrlist->message =
4575 string_sprintf("%s transport has empty hosts setting", tblock->name);
4576 addrlist->transport_return = PANIC;
4577 return FALSE; /* Only top address has status */
4578 }
4579
4580 /* If there was no expansion of hosts, save the host list for
4581 next time. */
4582
4583 if (!expanded_hosts) ob->hostlist = hostlist;
4584 }
4585
4586 /* This is not the first time this transport has been run in this delivery;
4587 the host list was built previously. */
4588
4589 else
4590 hostlist = ob->hostlist;
4591 }
4592
4593 /* The host list was supplied with the address. If hosts_randomize is set, we
4594 must sort it into a random order if it did not come from MX records and has not
4595 already been randomized (but don't bother if continuing down an existing
4596 connection). */
4597
4598 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
4599 {
4600 host_item *newlist = NULL;
4601 while (hostlist)
4602 {
4603 host_item *h = hostlist;
4604 hostlist = hostlist->next;
4605
4606 h->sort_key = random_number(100);
4607
4608 if (!newlist)
4609 {
4610 h->next = NULL;
4611 newlist = h;
4612 }
4613 else if (h->sort_key < newlist->sort_key)
4614 {
4615 h->next = newlist;
4616 newlist = h;
4617 }
4618 else
4619 {
4620 host_item *hh = newlist;
4621 while (hh->next)
4622 {
4623 if (h->sort_key < hh->next->sort_key) break;
4624 hh = hh->next;
4625 }
4626 h->next = hh->next;
4627 hh->next = h;
4628 }
4629 }
4630
4631 hostlist = addrlist->host_list = newlist;
4632 }
4633
4634 /* Sort out the default port. */
4635
4636 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
4637
4638 /* For each host-plus-IP-address on the list:
4639
4640 . If this is a continued delivery and the host isn't the one with the
4641 current connection, skip.
4642
4643 . If the status is unusable (i.e. previously failed or retry checked), skip.
4644
4645 . If no IP address set, get the address, either by turning the name into
4646 an address, calling gethostbyname if gethostbyname is on, or by calling
4647 the DNS. The DNS may yield multiple addresses, in which case insert the
4648 extra ones into the list.
4649
4650 . Get the retry data if not previously obtained for this address and set the
4651 field which remembers the state of this address. Skip if the retry time is
4652 not reached. If not, remember whether retry data was found. The retry string
4653 contains both the name and the IP address.
4654
4655 . Scan the list of addresses and mark those whose status is DEFER as
4656 PENDING_DEFER. These are the only ones that will be processed in this cycle
4657 of the hosts loop.
4658
4659 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
4660 Some addresses may be successfully delivered, others may fail, and yet
4661 others may get temporary errors and so get marked DEFER.
4662
4663 . The return from the delivery attempt is OK if a connection was made and a
4664 valid SMTP dialogue was completed. Otherwise it is DEFER.
4665
4666 . If OK, add a "remove" retry item for this host/IPaddress, if any.
4667
4668 . If fail to connect, or other defer state, add a retry item.
4669
4670 . If there are any addresses whose status is still DEFER, carry on to the
4671 next host/IPaddress, unless we have tried the number of hosts given
4672 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
4673 there is some fancy logic for hosts_max_try that means its limit can be
4674 overstepped in some circumstances.
4675
4676 If we get to the end of the list, all hosts have deferred at least one address,
4677 or not reached their retry times. If delay_after_cutoff is unset, it requests a
4678 delivery attempt to those hosts whose last try was before the arrival time of
4679 the current message. To cope with this, we have to go round the loop a second
4680 time. After that, set the status and error data for any addresses that haven't
4681 had it set already. */
4682
4683 for (int cutoff_retry = 0;
4684 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
4685 cutoff_retry++)
4686 {
4687 host_item *nexthost = NULL;
4688 int unexpired_hosts_tried = 0;
4689 BOOL continue_host_tried = FALSE;
4690
4691 retry_non_continued:
4692 for (host = hostlist;
4693 host
4694 && unexpired_hosts_tried < ob->hosts_max_try
4695 && total_hosts_tried < ob->hosts_max_try_hardlimit;
4696 host = nexthost)
4697 {
4698 int rc;
4699 int host_af;
4700 BOOL host_is_expired = FALSE;
4701 BOOL message_defer = FALSE;
4702 BOOL some_deferred = FALSE;
4703 address_item *first_addr = NULL;
4704 uschar *interface = NULL;
4705 uschar *retry_host_key = NULL;
4706 uschar *retry_message_key = NULL;
4707 uschar *serialize_key = NULL;
4708
4709 /* Default next host is next host. :-) But this can vary if the
4710 hosts_max_try limit is hit (see below). It may also be reset if a host
4711 address is looked up here (in case the host was multihomed). */
4712
4713 nexthost = host->next;
4714
4715 /* If the address hasn't yet been obtained from the host name, look it up
4716 now, unless the host is already marked as unusable. If it is marked as
4717 unusable, it means that the router was unable to find its IP address (in
4718 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
4719 the lookup failed last time. We don't get this far if *all* MX records
4720 point to non-existent hosts; that is treated as a hard error.
4721
4722 We can just skip this host entirely. When the hosts came from the router,
4723 the address will timeout based on the other host(s); when the address is
4724 looked up below, there is an explicit retry record added.
4725
4726 Note that we mustn't skip unusable hosts if the address is not unset; they
4727 may be needed as expired hosts on the 2nd time round the cutoff loop. */
4728
4729 if (!host->address)
4730 {
4731 int new_port, flags;
4732
4733 if (host->status >= hstatus_unusable)
4734 {
4735 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
4736 host->name);
4737 continue;
4738 }
4739
4740 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
4741
4742 /* The host name is permitted to have an attached port. Find it, and
4743 strip it from the name. Just remember it for now. */
4744
4745 new_port = host_item_get_port(host);
4746
4747 /* Count hosts looked up */
4748
4749 hosts_looked_up++;
4750
4751 /* Find by name if so configured, or if it's an IP address. We don't
4752 just copy the IP address, because we need the test-for-local to happen. */
4753
4754 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
4755 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
4756 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
4757
4758 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
4759 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
4760 else
4761 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
4762 &ob->dnssec, /* domains for request/require */
4763 NULL, NULL);
4764
4765 /* Update the host (and any additional blocks, resulting from
4766 multihoming) with a host-specific port, if any. */
4767
4768 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
4769
4770 /* Failure to find the host at this time (usually DNS temporary failure)
4771 is really a kind of routing failure rather than a transport failure.
4772 Therefore we add a retry item of the routing kind, not to stop us trying
4773 to look this name up here again, but to ensure the address gets timed
4774 out if the failures go on long enough. A complete failure at this point
4775 commonly points to a configuration error, but the best action is still
4776 to carry on for the next host. */
4777
4778 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
4779 {
4780 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
4781 expired = FALSE;
4782 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
4783 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
4784 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
4785 host->status = hstatus_unusable;
4786
4787 for (address_item * addr = addrlist; addr; addr = addr->next)
4788 {
4789 if (addr->transport_return != DEFER) continue;
4790 addr->basic_errno = ERRNO_UNKNOWNHOST;
4791 addr->message = string_sprintf(
4792 rc == HOST_FIND_SECURITY
4793 ? "lookup of IP address for %s was insecure"
4794 : "failed to lookup IP address for %s",
4795 host->name);
4796 }
4797 continue;
4798 }
4799
4800 /* If the host is actually the local host, we may have a problem, or
4801 there may be some cunning configuration going on. In the problem case,
4802 log things and give up. The default transport status is already DEFER. */
4803
4804 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
4805 {
4806 for (address_item * addr = addrlist; addr; addr = addr->next)
4807 {
4808 addr->basic_errno = 0;
4809 addr->message = string_sprintf("%s transport found host %s to be "
4810 "local", tblock->name, host->name);
4811 }
4812 goto END_TRANSPORT;
4813 }
4814 } /* End of block for IP address lookup */
4815
4816 /* If this is a continued delivery, we are interested only in the host
4817 which matches the name of the existing open channel. The check is put
4818 here after the local host lookup, in case the name gets expanded as a
4819 result of the lookup. Set expired FALSE, to save the outer loop executing
4820 twice. */
4821
4822 if (continue_hostname)
4823 if ( Ustrcmp(continue_hostname, host->name) != 0
4824 || Ustrcmp(continue_host_address, host->address) != 0
4825 )
4826 {
4827 expired = FALSE;
4828 continue; /* With next host */
4829 }
4830 else
4831 continue_host_tried = TRUE;
4832
4833 /* Reset the default next host in case a multihomed host whose addresses
4834 are not looked up till just above added to the host list. */
4835
4836 nexthost = host->next;
4837
4838 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
4839 domain is in queue_smtp_domains, we don't actually want to attempt any
4840 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
4841 there is a lookup defer in queue_smtp_domains, proceed as if the domain
4842 were not in it. We don't want to hold up all SMTP deliveries! Except when
4843 doing a two-stage queue run, don't do this if forcing. */
4844
4845 if ((!f.deliver_force || f.queue_2stage) && (f.queue_smtp ||
4846 match_isinlist(addrlist->domain,
4847 (const uschar **)&queue_smtp_domains, 0,
4848 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
4849 {
4850 expired = FALSE;
4851 for (address_item * addr = addrlist; addr; addr = addr->next)
4852 if (addr->transport_return == DEFER)
4853 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
4854 continue; /* With next host */
4855 }
4856
4857 /* Count hosts being considered - purely for an intelligent comment
4858 if none are usable. */
4859
4860 hosts_total++;
4861
4862 /* Set $host and $host address now in case they are needed for the
4863 interface expansion or the serialize_hosts check; they remain set if an
4864 actual delivery happens. */
4865
4866 deliver_host = host->name;
4867 deliver_host_address = host->address;
4868 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
4869 : host->dnssec == DS_NO ? US"no"
4870 : US"";
4871
4872 /* Set up a string for adding to the retry key if the port number is not
4873 the standard SMTP port. A host may have its own port setting that overrides
4874 the default. */
4875
4876 pistring = string_sprintf(":%d", host->port == PORT_NONE
4877 ? defport : host->port);
4878 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
4879
4880 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
4881 string is set, even if constant (as different transports can have different
4882 constant settings), we must add it to the key that is used for retries,
4883 because connections to the same host from a different interface should be
4884 treated separately. */
4885
4886 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
4887 {
4888 uschar * s = ob->interface;
4889 if (s && *s)
4890 {
4891 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
4892 return FALSE;
4893 pistring = string_sprintf("%s/%s", pistring, interface);
4894 }
4895 }
4896
4897 /* The first time round the outer loop, check the status of the host by
4898 inspecting the retry data. The second time round, we are interested only
4899 in expired hosts that haven't been tried since this message arrived. */
4900
4901 if (cutoff_retry == 0)
4902 {
4903 BOOL incl_ip;
4904 /* Ensure the status of the address is set by checking retry data if
4905 necessary. There may be host-specific retry data (applicable to all
4906 messages) and also data for retries of a specific message at this host.
4907 If either of these retry records are actually read, the keys used are
4908 returned to save recomputing them later. */
4909
4910 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4911 US"retry_include_ip_address", ob->retry_include_ip_address,
4912 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4913 continue; /* with next host */
4914
4915 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4916 incl_ip, &retry_host_key, &retry_message_key);
4917
4918 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4919 host->address ? host->address : US"", pistring,
4920 host->status == hstatus_usable ? "usable"
4921 : host->status == hstatus_unusable ? "unusable"
4922 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
4923
4924 /* Skip this address if not usable at this time, noting if it wasn't
4925 actually expired, both locally and in the address. */
4926
4927 switch (host->status)
4928 {
4929 case hstatus_unusable:
4930 expired = FALSE;
4931 setflag(addrlist, af_retry_skipped);
4932 /* Fall through */
4933
4934 case hstatus_unusable_expired:
4935 switch (host->why)
4936 {
4937 case hwhy_retry: hosts_retry++; break;
4938 case hwhy_failed: hosts_fail++; break;
4939 case hwhy_insecure:
4940 case hwhy_deferred: hosts_defer++; break;
4941 }
4942
4943 /* If there was a retry message key, implying that previously there
4944 was a message-specific defer, we don't want to update the list of
4945 messages waiting for these hosts. */
4946
4947 if (retry_message_key) update_waiting = FALSE;
4948 continue; /* With the next host or IP address */
4949 }
4950 }
4951
4952 /* Second time round the loop: if the address is set but expired, and
4953 the message is newer than the last try, let it through. */
4954
4955 else
4956 {
4957 if ( !host->address
4958 || host->status != hstatus_unusable_expired
4959 || host->last_try > received_time.tv_sec)
4960 continue;
4961 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4962 host->name, host->address, pistring);
4963 host_is_expired = TRUE;
4964 }
4965
4966 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4967 it remains TRUE only if all hosts are expired and none are actually tried.
4968 */
4969
4970 expired = FALSE;
4971
4972 /* If this host is listed as one to which access must be serialized,
4973 see if another Exim process has a connection to it, and if so, skip
4974 this host. If not, update the database to record our connection to it
4975 and remember this for later deletion. Do not do any of this if we are
4976 sending the message down a pre-existing connection. */
4977
4978 if ( !continue_hostname
4979 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
4980 {
4981 serialize_key = string_sprintf("host-serialize-%s", host->name);
4982 if (!enq_start(serialize_key, 1))
4983 {
4984 DEBUG(D_transport)
4985 debug_printf("skipping host %s because another Exim process "
4986 "is connected to it\n", host->name);
4987 hosts_serial++;
4988 continue;
4989 }
4990 }
4991
4992 /* OK, we have an IP address that is not waiting for its retry time to
4993 arrive (it might be expired) OR (second time round the loop) we have an
4994 expired host that hasn't been tried since the message arrived. Have a go
4995 at delivering the message to it. First prepare the addresses by flushing
4996 out the result of previous attempts, and finding the first address that
4997 is still to be delivered. */
4998
4999 first_addr = prepare_addresses(addrlist, host);
5000
5001 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5002 message_id, host->name, host->address, addrlist->address,
5003 addrlist->next ? ", ..." : "");
5004
5005 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5006 message_id, host->name, host->address, pistring, addrlist->address,
5007 addrlist->next ? ", ..." : "");
5008
5009 /* This is not for real; don't do the delivery. If there are
5010 any remaining hosts, list them. */
5011
5012 if (f.dont_deliver)
5013 {
5014 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
5015 for (address_item * addr = addrlist; addr; addr = addr->next)
5016 {
5017 addr->host_used = host;
5018 addr->special_action = '*';
5019 addr->message = US"delivery bypassed by -N option";
5020 }
5021 DEBUG(D_transport)
5022 {
5023 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5024 "*** host and remaining hosts:\n", tblock->name);
5025 for (host_item * host2 = host; host2; host2 = host2->next)
5026 debug_printf(" %s [%s]\n", host2->name,
5027 host2->address ? host2->address : US"unset");
5028 }
5029 rc = OK;
5030 }
5031
5032 /* This is for real. If the host is expired, we don't count it for
5033 hosts_max_retry. This ensures that all hosts must expire before an address
5034 is timed out, unless hosts_max_try_hardlimit (which protects against
5035 lunatic DNS configurations) is reached.
5036
5037 If the host is not expired and we are about to hit the hosts_max_retry
5038 limit, check to see if there is a subsequent hosts with a different MX
5039 value. If so, make that the next host, and don't count this one. This is a
5040 heuristic to make sure that different MXs do get tried. With a normal kind
5041 of retry rule, they would get tried anyway when the earlier hosts were
5042 delayed, but if the domain has a "retry every time" type of rule - as is
5043 often used for the the very large ISPs, that won't happen. */
5044
5045 else
5046 {
5047 host_item * thost;
5048 /* Make a copy of the host if it is local to this invocation
5049 of the transport. */
5050
5051 if (expanded_hosts)
5052 {
5053 thost = store_get(sizeof(host_item));
5054 *thost = *host;
5055 thost->name = string_copy(host->name);
5056 thost->address = string_copy(host->address);
5057 }
5058 else
5059 thost = host;
5060
5061 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5062 {
5063 DEBUG(D_transport)
5064 debug_printf("hosts_max_try limit reached with this host\n");
5065 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5066 {
5067 nexthost = h;
5068 unexpired_hosts_tried--;
5069 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5070 "and will be tried\n");
5071 break;
5072 }
5073 }
5074
5075 /* Attempt the delivery. */
5076
5077 total_hosts_tried++;
5078 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5079 &message_defer, FALSE);
5080
5081 /* Yield is one of:
5082 OK => connection made, each address contains its result;
5083 message_defer is set for message-specific defers (when all
5084 recipients are marked defer)
5085 DEFER => there was a non-message-specific delivery problem;
5086 ERROR => there was a problem setting up the arguments for a filter,
5087 or there was a problem with expanding added headers
5088 */
5089
5090 /* If the result is not OK, there was a non-message-specific problem.
5091 If the result is DEFER, we need to write to the logs saying what happened
5092 for this particular host, except in the case of authentication and TLS
5093 failures, where the log has already been written. If all hosts defer a
5094 general message is written at the end. */
5095
5096 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5097 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5098 write_logs(host, first_addr->message, first_addr->basic_errno);
5099
5100 #ifndef DISABLE_EVENT
5101 if (rc == DEFER)
5102 deferred_event_raise(first_addr, host);
5103 #endif
5104
5105 /* If STARTTLS was accepted, but there was a failure in setting up the
5106 TLS session (usually a certificate screwup), and the host is not in
5107 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5108 TLS forcibly turned off. We have to start from scratch with a new SMTP
5109 connection. That's why the retry is done from here, not from within
5110 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5111 session, so the in-clear transmission after those errors, if permitted,
5112 happens inside smtp_deliver().] */
5113
5114 #ifndef DISABLE_TLS
5115 if ( rc == DEFER
5116 && first_addr->basic_errno == ERRNO_TLSFAILURE
5117 && ob->tls_tempfail_tryclear
5118 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5119 )
5120 {
5121 log_write(0, LOG_MAIN,
5122 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5123 first_addr->message, host->name, host->address);
5124 first_addr = prepare_addresses(addrlist, host);
5125 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5126 &message_defer, TRUE);
5127 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5128 write_logs(host, first_addr->message, first_addr->basic_errno);
5129 # ifndef DISABLE_EVENT
5130 if (rc == DEFER)
5131 deferred_event_raise(first_addr, host);
5132 # endif
5133 }
5134 #endif /*DISABLE_TLS*/
5135 }
5136
5137 /* Delivery attempt finished */
5138
5139 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5140 message_id, host->name, host->address, pistring, addrlist->address,
5141 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5142
5143 /* Release serialization if set up */
5144
5145 if (serialize_key) enq_end(serialize_key);
5146
5147 /* If the result is DEFER, or if a host retry record is known to exist, we
5148 need to add an item to the retry chain for updating the retry database
5149 at the end of delivery. We only need to add the item to the top address,
5150 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5151 for any other delivery attempts using the same address. (It is copied into
5152 the unusable tree at the outer level, so even if different address blocks
5153 contain the same address, it still won't get tried again.) */
5154
5155 if (rc == DEFER || retry_host_key)
5156 {
5157 int delete_flag = rc != DEFER ? rf_delete : 0;
5158 if (!retry_host_key)
5159 {
5160 BOOL incl_ip;
5161 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5162 US"retry_include_ip_address", ob->retry_include_ip_address,
5163 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5164 incl_ip = TRUE; /* error; use most-specific retry record */
5165
5166 retry_host_key = incl_ip
5167 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5168 : string_sprintf("T:%S%s", host->name, pistring);
5169 }
5170
5171 /* If a delivery of another message over an existing SMTP connection
5172 yields DEFER, we do NOT set up retry data for the host. This covers the
5173 case when there are delays in routing the addresses in the second message
5174 that are so long that the server times out. This is alleviated by not
5175 routing addresses that previously had routing defers when handling an
5176 existing connection, but even so, this case may occur (e.g. if a
5177 previously happily routed address starts giving routing defers). If the
5178 host is genuinely down, another non-continued message delivery will
5179 notice it soon enough. */
5180
5181 if (delete_flag != 0 || !continue_hostname)
5182 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5183
5184 /* We may have tried an expired host, if its retry time has come; ensure
5185 the status reflects the expiry for the benefit of any other addresses. */
5186
5187 if (rc == DEFER)
5188 {
5189 host->status = host_is_expired
5190 ? hstatus_unusable_expired : hstatus_unusable;
5191 host->why = hwhy_deferred;
5192 }
5193 }
5194
5195 /* If message_defer is set (host was OK, but every recipient got deferred
5196 because of some message-specific problem), or if that had happened
5197 previously so that a message retry key exists, add an appropriate item
5198 to the retry chain. Note that if there was a message defer but now there is
5199 a host defer, the message defer record gets deleted. That seems perfectly
5200 reasonable. Also, stop the message from being remembered as waiting
5201 for specific hosts. */
5202
5203 if (message_defer || retry_message_key)
5204 {
5205 int delete_flag = message_defer ? 0 : rf_delete;
5206 if (!retry_message_key)
5207 {
5208 BOOL incl_ip;
5209 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5210 US"retry_include_ip_address", ob->retry_include_ip_address,
5211 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5212 incl_ip = TRUE; /* error; use most-specific retry record */
5213
5214 retry_message_key = incl_ip
5215 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5216 message_id)
5217 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5218 }
5219 retry_add_item(addrlist, retry_message_key,
5220 rf_message | rf_host | delete_flag);
5221 update_waiting = FALSE;
5222 }
5223
5224 /* Any return other than DEFER (that is, OK or ERROR) means that the
5225 addresses have got their final statuses filled in for this host. In the OK
5226 case, see if any of them are deferred. */
5227
5228 if (rc == OK)
5229 for (address_item * addr = addrlist; addr; addr = addr->next)
5230 if (addr->transport_return == DEFER)
5231 {
5232 some_deferred = TRUE;
5233 break;
5234 }
5235
5236 /* If no addresses deferred or the result was ERROR, return. We do this for
5237 ERROR because a failing filter set-up or add_headers expansion is likely to
5238 fail for any host we try. */
5239
5240 if (rc == ERROR || (rc == OK && !some_deferred))
5241 {
5242 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5243 return TRUE; /* Each address has its status */
5244 }
5245
5246 /* If the result was DEFER or some individual addresses deferred, let
5247 the loop run to try other hosts with the deferred addresses, except for the
5248 case when we were trying to deliver down an existing channel and failed.
5249 Don't try any other hosts in this case. */
5250
5251 if (continue_hostname) break;
5252
5253 /* If the whole delivery, or some individual addresses, were deferred and
5254 there are more hosts that could be tried, do not count this host towards
5255 the hosts_max_try limit if the age of the message is greater than the
5256 maximum retry time for this host. This means we may try try all hosts,
5257 ignoring the limit, when messages have been around for some time. This is
5258 important because if we don't try all hosts, the address will never time
5259 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5260
5261 if ((rc == DEFER || some_deferred) && nexthost)
5262 {
5263 BOOL timedout;
5264 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5265
5266 if (retry && retry->rules)
5267 {
5268 retry_rule *last_rule;
5269 for (last_rule = retry->rules;
5270 last_rule->next;
5271 last_rule = last_rule->next);
5272 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5273 }
5274 else timedout = TRUE; /* No rule => timed out */
5275
5276 if (timedout)
5277 {
5278 unexpired_hosts_tried--;
5279 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5280 "hosts_max_try (message older than host's retry time)\n");
5281 }
5282 }
5283
5284 DEBUG(D_transport)
5285 {
5286 if (unexpired_hosts_tried >= ob->hosts_max_try)
5287 debug_printf("reached transport hosts_max_try limit %d\n",
5288 ob->hosts_max_try);
5289 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5290 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5291 ob->hosts_max_try_hardlimit);
5292 }
5293
5294 if (f.running_in_test_harness) millisleep(500); /* let server debug out */
5295 } /* End of loop for trying multiple hosts. */
5296
5297 /* If we failed to find a matching host in the list, for an already-open
5298 connection, just close it and start over with the list. This can happen
5299 for routing that changes from run to run, or big multi-IP sites with
5300 round-robin DNS. */
5301
5302 if (continue_hostname && !continue_host_tried)
5303 {
5304 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5305
5306 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5307 #ifndef DISABLE_TLS
5308 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5309 transport */
5310 /*XXX doublecheck that! */
5311
5312 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5313 {
5314 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5315 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5316 cutthrough.cctx.tls_ctx = NULL;
5317 cutthrough.is_tls = FALSE;
5318 }
5319 else
5320 #else
5321 (void) write(fd, US"QUIT\r\n", 6);
5322 #endif
5323 (void) close(fd);
5324 cutthrough.cctx.sock = -1;
5325 continue_hostname = NULL;
5326 goto retry_non_continued;
5327 }
5328
5329 /* This is the end of the loop that repeats iff expired is TRUE and
5330 ob->delay_after_cutoff is FALSE. The second time round we will
5331 try those hosts that haven't been tried since the message arrived. */
5332
5333 DEBUG(D_transport)
5334 {
5335 debug_printf("all IP addresses skipped or deferred at least one address\n");
5336 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5337 debug_printf("retrying IP addresses not tried since message arrived\n");
5338 }
5339 }
5340
5341
5342 /* Get here if all IP addresses are skipped or defer at least one address. In
5343 MUA wrapper mode, this will happen only for connection or other non-message-
5344 specific failures. Force the delivery status for all addresses to FAIL. */
5345
5346 if (mua_wrapper)
5347 {
5348 for (address_item * addr = addrlist; addr; addr = addr->next)
5349 addr->transport_return = FAIL;
5350 goto END_TRANSPORT;
5351 }
5352
5353 /* In the normal, non-wrapper case, add a standard message to each deferred
5354 address if there hasn't been an error, that is, if it hasn't actually been
5355 tried this time. The variable "expired" will be FALSE if any deliveries were
5356 actually tried, or if there was at least one host that was not expired. That
5357 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
5358 a delivery has been tried, an error code will be set, and the failing of the
5359 message is handled by the retry code later.
5360
5361 If queue_smtp is set, or this transport was called to send a subsequent message
5362 down an existing TCP/IP connection, and something caused the host not to be
5363 found, we end up here, but can detect these cases and handle them specially. */
5364
5365 for (address_item * addr = addrlist; addr; addr = addr->next)
5366 {
5367 /* If host is not NULL, it means that we stopped processing the host list
5368 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
5369 means we need to behave as if some hosts were skipped because their retry
5370 time had not come. Specifically, this prevents the address from timing out.
5371 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
5372 hosts were tried. */
5373
5374 if (host)
5375 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5376 {
5377 DEBUG(D_transport)
5378 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
5379 "hosts were tried\n");
5380 }
5381 else
5382 {
5383 DEBUG(D_transport)
5384 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
5385 setflag(addr, af_retry_skipped);
5386 }
5387
5388 if (f.queue_smtp) /* no deliveries attempted */
5389 {
5390 addr->transport_return = DEFER;
5391 addr->basic_errno = 0;
5392 addr->message = US"SMTP delivery explicitly queued";
5393 }
5394
5395 else if ( addr->transport_return == DEFER
5396 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
5397 && !addr->message
5398 )
5399 {
5400 addr->basic_errno = ERRNO_HRETRY;
5401 if (continue_hostname)
5402 addr->message = US"no host found for existing SMTP connection";
5403 else if (expired)
5404 {
5405 setflag(addr, af_pass_message); /* This is not a security risk */
5406 addr->message = string_sprintf(
5407 "all hosts%s have been failing for a long time %s",
5408 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
5409 ob->delay_after_cutoff
5410 ? US"(and retry time not reached)"
5411 : US"and were last tried after this message arrived");
5412
5413 /* If we are already using fallback hosts, or there are no fallback hosts
5414 defined, convert the result to FAIL to cause a bounce. */
5415
5416 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
5417 addr->transport_return = FAIL;
5418 }
5419 else
5420 {
5421 const char * s;
5422 if (hosts_retry == hosts_total)
5423 s = "retry time not reached for any host%s";
5424 else if (hosts_fail == hosts_total)
5425 s = "all host address lookups%s failed permanently";
5426 else if (hosts_defer == hosts_total)
5427 s = "all host address lookups%s failed temporarily";
5428 else if (hosts_serial == hosts_total)
5429 s = "connection limit reached for all hosts%s";
5430 else if (hosts_fail+hosts_defer == hosts_total)
5431 s = "all host address lookups%s failed";
5432 else
5433 s = "some host address lookups failed and retry time "
5434 "not reached for other hosts or connection limit reached%s";
5435
5436 addr->message = string_sprintf(s,
5437 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
5438 }
5439 }
5440 }
5441
5442 /* Update the database which keeps information about which messages are waiting
5443 for which hosts to become available. For some message-specific errors, the
5444 update_waiting flag is turned off because we don't want follow-on deliveries in
5445 those cases. If this transport instance is explicitly limited to one message
5446 per connection then follow-on deliveries are not possible and there's no need
5447 to create/update the per-transport wait-<transport_name> database. */
5448
5449 if (update_waiting && tblock->connection_max_messages != 1)
5450 transport_update_waiting(hostlist, tblock->name);
5451
5452 END_TRANSPORT:
5453
5454 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5455
5456 return TRUE; /* Each address has its status */
5457 }
5458
5459 #endif /*!MACRO_PREDEF*/
5460 /* vi: aw ai sw=2
5461 */
5462 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.