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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 set_errno_nohost(sx->addrlist,
2129 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2130 sx->verify ? US strerror(errno) : NULL,
2131 DEFER, FALSE);
2132 sx->send_quit = FALSE;
2133 return DEFER;
2134 }
2135 }
2136 /* Expand the greeting message while waiting for the initial response. (Makes
2137 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2138 delayed till here so that $sending_interface and $sending_port are set. */
2139 /*XXX early-pipe: they still will not be. Is there any way to find out what they
2140 will be? Somehow I doubt it. */
2141
2142 if (sx->helo_data)
2143 if (!(sx->helo_data = expand_string(sx->helo_data)))
2144 if (sx->verify)
2145 log_write(0, LOG_MAIN|LOG_PANIC,
2146 "<%s>: failed to expand transport's helo_data value for callout: %s",
2147 sx->addrlist->address, expand_string_message);
2148
2149 #ifdef SUPPORT_I18N
2150 if (sx->helo_data)
2151 {
2152 expand_string_message = NULL;
2153 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2154 &expand_string_message)),
2155 expand_string_message)
2156 if (sx->verify)
2157 log_write(0, LOG_MAIN|LOG_PANIC,
2158 "<%s>: failed to expand transport's helo_data value for callout: %s",
2159 sx->addrlist->address, expand_string_message);
2160 else
2161 sx->helo_data = NULL;
2162 }
2163 #endif
2164
2165 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2166 is nevertheless a reasonably clean way of programming this kind of logic,
2167 where you want to escape on any error. */
2168
2169 if (!sx->smtps)
2170 {
2171 #ifdef EXPERIMENTAL_PIPE_CONNECT
2172 if (sx->early_pipe_active)
2173 {
2174 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2175 sx->outblock.cmd_count = 1;
2176 }
2177 else
2178 #endif
2179 {
2180 #ifdef TCP_QUICKACK
2181 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2182 sizeof(off));
2183 #endif
2184 if (!smtp_reap_banner(sx))
2185 goto RESPONSE_FAILED;
2186 }
2187
2188 #ifndef DISABLE_EVENT
2189 {
2190 uschar * s;
2191 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2192 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2193 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer);
2194 if (s)
2195 {
2196 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2197 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2198 DEFER, FALSE);
2199 yield = DEFER;
2200 goto SEND_QUIT;
2201 }
2202 }
2203 #endif
2204
2205 /* Now check if the helo_data expansion went well, and sign off cleanly if
2206 it didn't. */
2207
2208 if (!sx->helo_data)
2209 {
2210 message = string_sprintf("failed to expand helo_data: %s",
2211 expand_string_message);
2212 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2213 yield = DEFER;
2214 goto SEND_QUIT;
2215 }
2216 }
2217
2218 /** Debugging without sending a message
2219 sx->addrlist->transport_return = DEFER;
2220 goto SEND_QUIT;
2221 **/
2222
2223 /* Errors that occur after this point follow an SMTP command, which is
2224 left in big_buffer by smtp_write_command() for use in error messages. */
2225
2226 smtp_command = big_buffer;
2227
2228 /* Tell the remote who we are...
2229
2230 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2231 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2232 greeting is of this form. The assumption was that the far end supports it
2233 properly... but experience shows that there are some that give 5xx responses,
2234 even though the banner includes "ESMTP" (there's a bloody-minded one that
2235 says "ESMTP not spoken here"). Cope with that case.
2236
2237 September 2000: Time has passed, and it seems reasonable now to always send
2238 EHLO at the start. It is also convenient to make the change while installing
2239 the TLS stuff.
2240
2241 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2242 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2243 would be no way to send out the mails, so there is now a host list
2244 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2245 PIPELINING problem as well. Maybe it can also be useful to cure other
2246 problems with broken servers.
2247
2248 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2249 Then somebody tried it with a Microsoft mailer... It seems that all other
2250 mailers use upper case for some reason (the RFC is quite clear about case
2251 independence) so, for peace of mind, I gave in. */
2252
2253 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2254
2255 /* Alas; be careful, since this goto is not an error-out, so conceivably
2256 we might set data between here and the target which we assume to exist
2257 and be usable. I can see this coming back to bite us. */
2258 #ifndef DISABLE_TLS
2259 if (sx->smtps)
2260 {
2261 smtp_peer_options |= OPTION_TLS;
2262 suppress_tls = FALSE;
2263 ob->tls_tempfail_tryclear = FALSE;
2264 smtp_command = US"SSL-on-connect";
2265 goto TLS_NEGOTIATE;
2266 }
2267 #endif
2268
2269 if (sx->esmtp)
2270 {
2271 if (smtp_write_command(sx,
2272 #ifdef EXPERIMENTAL_PIPE_CONNECT
2273 sx->early_pipe_active ? SCMD_BUFFER :
2274 #endif
2275 SCMD_FLUSH,
2276 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2277 goto SEND_FAILED;
2278 sx->esmtp_sent = TRUE;
2279
2280 #ifdef EXPERIMENTAL_PIPE_CONNECT
2281 if (sx->early_pipe_active)
2282 {
2283 sx->pending_EHLO = TRUE;
2284
2285 /* If we have too many authenticators to handle and might need to AUTH
2286 for this transport, pipeline no further as we will need the
2287 list of auth methods offered. Reap the banner and EHLO. */
2288
2289 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2290 && f.smtp_in_early_pipe_no_auth)
2291 {
2292 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2293 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2294 goto SEND_FAILED;
2295 if (sync_responses(sx, 2, 0) != 0)
2296 {
2297 HDEBUG(D_transport)
2298 debug_printf("failed reaping pipelined cmd responses\n");
2299 goto RESPONSE_FAILED;
2300 }
2301 sx->early_pipe_active = FALSE;
2302 }
2303 }
2304 else
2305 #endif
2306 if (!smtp_reap_ehlo(sx))
2307 goto RESPONSE_FAILED;
2308 }
2309 else
2310 DEBUG(D_transport)
2311 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2312
2313 #ifdef EXPERIMENTAL_PIPE_CONNECT
2314 if (!sx->early_pipe_active)
2315 #endif
2316 if (!sx->esmtp)
2317 {
2318 BOOL good_response;
2319 int n = sizeof(sx->buffer);
2320 uschar * rsp = sx->buffer;
2321
2322 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
2323 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
2324
2325 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2326 goto SEND_FAILED;
2327 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2328 #ifdef EXPERIMENTAL_DSN_INFO
2329 sx->helo_response = string_copy(rsp);
2330 #endif
2331 if (!good_response)
2332 {
2333 /* Handle special logging for a closed connection after HELO
2334 when had previously sent EHLO */
2335
2336 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2337 {
2338 errno = ERRNO_SMTPCLOSED;
2339 goto EHLOHELO_FAILED;
2340 }
2341 memmove(sx->buffer, rsp, Ustrlen(rsp));
2342 goto RESPONSE_FAILED;
2343 }
2344 }
2345
2346 if (sx->esmtp || sx->lmtp)
2347 {
2348 #ifdef EXPERIMENTAL_PIPE_CONNECT
2349 if (!sx->early_pipe_active)
2350 #endif
2351 {
2352 sx->peer_offered = ehlo_response(sx->buffer,
2353 OPTION_TLS /* others checked later */
2354 #ifdef EXPERIMENTAL_PIPE_CONNECT
2355 | (sx->early_pipe_ok
2356 ? OPTION_IGNQ
2357 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2358 #ifdef SUPPORT_I18N
2359 | OPTION_UTF8
2360 #endif
2361 | OPTION_EARLY_PIPE
2362 : 0
2363 )
2364 #endif
2365 );
2366 #ifdef EXPERIMENTAL_PIPE_CONNECT
2367 if (sx->early_pipe_ok)
2368 {
2369 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2370
2371 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2372 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2373 {
2374 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2375 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2376 write_ehlo_cache_entry(sx);
2377 }
2378 }
2379 #endif
2380 }
2381
2382 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2383
2384 #ifndef DISABLE_TLS
2385 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2386 #endif
2387 }
2388 }
2389
2390 /* For continuing deliveries down the same channel, having re-exec'd the socket
2391 is the standard input; for a socket held open from verify it is recorded
2392 in the cutthrough context block. Either way we don't need to redo EHLO here
2393 (but may need to do so for TLS - see below).
2394 Set up the pointer to where subsequent commands will be left, for
2395 error messages. Note that smtp_peer_options will have been
2396 set from the command line if they were set in the process that passed the
2397 connection on. */
2398
2399 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2400 as the continue goes via transport_pass_socket() and doublefork and exec.
2401 It does not wait. Unclear how we keep separate host's responses
2402 separate - we could match up by host ip+port as a bodge. */
2403
2404 else
2405 {
2406 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2407 {
2408 sx->cctx = cutthrough.cctx;
2409 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2410 }
2411 else
2412 {
2413 sx->cctx.sock = 0; /* stdin */
2414 sx->cctx.tls_ctx = NULL;
2415 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2416 }
2417 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2418 smtp_command = big_buffer;
2419 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2420
2421 /* For a continued connection with TLS being proxied for us, or a
2422 held-open verify connection with TLS, nothing more to do. */
2423
2424 if ( continue_proxy_cipher
2425 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2426 && cutthrough.is_tls)
2427 )
2428 {
2429 sx->peer_offered = smtp_peer_options;
2430 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2431 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2432 continue_proxy_cipher ? "proxied" : "verify conn with");
2433 return OK;
2434 }
2435 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2436 }
2437
2438 /* If TLS is available on this connection, whether continued or not, attempt to
2439 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2440 send another EHLO - the server may give a different answer in secure mode. We
2441 use a separate buffer for reading the response to STARTTLS so that if it is
2442 negative, the original EHLO data is available for subsequent analysis, should
2443 the client not be required to use TLS. If the response is bad, copy the buffer
2444 for error analysis. */
2445
2446 #ifndef DISABLE_TLS
2447 if ( smtp_peer_options & OPTION_TLS
2448 && !suppress_tls
2449 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2450 && ( !sx->verify
2451 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2452 ) )
2453 {
2454 uschar buffer2[4096];
2455
2456 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2457 goto SEND_FAILED;
2458
2459 #ifdef EXPERIMENTAL_PIPE_CONNECT
2460 /* If doing early-pipelining reap the banner and EHLO-response but leave
2461 the response for the STARTTLS we just sent alone. */
2462
2463 if (sx->early_pipe_active && sync_responses(sx, 2, 0) != 0)
2464 {
2465 HDEBUG(D_transport)
2466 debug_printf("failed reaping pipelined cmd responses\n");
2467 goto RESPONSE_FAILED;
2468 }
2469 #endif
2470
2471 /* If there is an I/O error, transmission of this message is deferred. If
2472 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2473 false, we also defer. However, if there is a temporary rejection of STARTTLS
2474 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2475 STARTTLS, we carry on. This means we will try to send the message in clear,
2476 unless the host is in hosts_require_tls (tested below). */
2477
2478 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2479 {
2480 if ( errno != 0
2481 || buffer2[0] == 0
2482 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2483 )
2484 {
2485 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2486 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2487 goto RESPONSE_FAILED;
2488 }
2489 }
2490
2491 /* STARTTLS accepted: try to negotiate a TLS session. */
2492
2493 else
2494 TLS_NEGOTIATE:
2495 {
2496 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2497 {
2498 /* TLS negotiation failed; give an error. From outside, this function may
2499 be called again to try in clear on a new connection, if the options permit
2500 it for this host. */
2501 #ifdef USE_GNUTLS
2502 GNUTLS_CONN_FAILED:
2503 #endif
2504 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2505
2506 # ifdef SUPPORT_DANE
2507 if (sx->conn_args.dane)
2508 {
2509 log_write(0, LOG_MAIN,
2510 "DANE attempt failed; TLS connection to %s [%s]: %s",
2511 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2512 # ifndef DISABLE_EVENT
2513 (void) event_raise(sx->conn_args.tblock->event_action,
2514 US"dane:fail", US"validation-failure"); /* could do with better detail */
2515 # endif
2516 }
2517 # endif
2518
2519 errno = ERRNO_TLSFAILURE;
2520 message = string_sprintf("TLS session: %s", tls_errstr);
2521 sx->send_quit = FALSE;
2522 goto TLS_FAILED;
2523 }
2524
2525 /* TLS session is set up */
2526
2527 smtp_peer_options_wrap = smtp_peer_options;
2528 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2529 if (addr->transport_return == PENDING_DEFER)
2530 {
2531 addr->cipher = tls_out.cipher;
2532 addr->ourcert = tls_out.ourcert;
2533 addr->peercert = tls_out.peercert;
2534 addr->peerdn = tls_out.peerdn;
2535 addr->ocsp = tls_out.ocsp;
2536 }
2537 }
2538 }
2539
2540 /* if smtps, we'll have smtp_command set to something else; always safe to
2541 reset it here. */
2542 smtp_command = big_buffer;
2543
2544 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2545 helo_data is null, we are dealing with a connection that was passed from
2546 another process, and so we won't have expanded helo_data above. We have to
2547 expand it here. $sending_ip_address and $sending_port are set up right at the
2548 start of the Exim process (in exim.c). */
2549
2550 if (tls_out.active.sock >= 0)
2551 {
2552 uschar * greeting_cmd;
2553
2554 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2555 {
2556 uschar *message = string_sprintf("failed to expand helo_data: %s",
2557 expand_string_message);
2558 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2559 yield = DEFER;
2560 goto SEND_QUIT;
2561 }
2562
2563 #ifdef EXPERIMENTAL_PIPE_CONNECT
2564 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2565 We're unlikely to get the group sent and delivered before the server sends its
2566 banner, but it's still worth sending as a group.
2567 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2568 the reverse. */
2569
2570 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2571 {
2572 sx->peer_offered = sx->ehlo_resp.crypted_features;
2573 if ((sx->early_pipe_active =
2574 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2575 DEBUG(D_transport) debug_printf("Using cached crypted PIPE_CONNECT\n");
2576 }
2577 #endif
2578
2579 /* For SMTPS we need to wait for the initial OK response. */
2580 if (sx->smtps)
2581 #ifdef EXPERIMENTAL_PIPE_CONNECT
2582 if (sx->early_pipe_active)
2583 {
2584 sx->pending_BANNER = TRUE;
2585 sx->outblock.cmd_count = 1;
2586 }
2587 else
2588 #endif
2589 if (!smtp_reap_banner(sx))
2590 goto RESPONSE_FAILED;
2591
2592 if (sx->lmtp)
2593 greeting_cmd = US"LHLO";
2594 else if (sx->esmtp)
2595 greeting_cmd = US"EHLO";
2596 else
2597 {
2598 greeting_cmd = US"HELO";
2599 DEBUG(D_transport)
2600 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2601 }
2602
2603 if (smtp_write_command(sx,
2604 #ifdef EXPERIMENTAL_PIPE_CONNECT
2605 sx->early_pipe_active ? SCMD_BUFFER :
2606 #endif
2607 SCMD_FLUSH,
2608 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2609 goto SEND_FAILED;
2610
2611 #ifdef EXPERIMENTAL_PIPE_CONNECT
2612 if (sx->early_pipe_active)
2613 sx->pending_EHLO = TRUE;
2614 else
2615 #endif
2616 {
2617 if (!smtp_reap_ehlo(sx))
2618 #ifdef USE_GNUTLS
2619 {
2620 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2621 cert late, under TLS1.3 - which means here; the first time we try to
2622 receive crypted data. Treat it as if it was a connect-time failure.
2623 See also the early-pipe equivalent... which will be hard; every call
2624 to sync_responses will need to check the result.
2625 It would be nicer to have GnuTLS check the cert during the handshake.
2626 Can it do that, with all the flexibility we need? */
2627
2628 tls_errstr = US"error on first read";
2629 goto GNUTLS_CONN_FAILED;
2630 }
2631 #else
2632 goto RESPONSE_FAILED;
2633 #endif
2634 smtp_peer_options = 0;
2635 }
2636 }
2637
2638 /* If the host is required to use a secure channel, ensure that we
2639 have one. */
2640
2641 else if ( sx->smtps
2642 # ifdef SUPPORT_DANE
2643 || sx->conn_args.dane
2644 # endif
2645 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2646 )
2647 {
2648 errno = ERRNO_TLSREQUIRED;
2649 message = string_sprintf("a TLS session is required, but %s",
2650 smtp_peer_options & OPTION_TLS
2651 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2652 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2653 if (sx->conn_args.dane)
2654 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2655 smtp_peer_options & OPTION_TLS
2656 ? US"validation-failure" /* could do with better detail */
2657 : US"starttls-not-supported");
2658 # endif
2659 goto TLS_FAILED;
2660 }
2661 #endif /*DISABLE_TLS*/
2662
2663 /* If TLS is active, we have just started it up and re-done the EHLO command,
2664 so its response needs to be analyzed. If TLS is not active and this is a
2665 continued session down a previously-used socket, we haven't just done EHLO, so
2666 we skip this. */
2667
2668 if (continue_hostname == NULL
2669 #ifndef DISABLE_TLS
2670 || tls_out.active.sock >= 0
2671 #endif
2672 )
2673 {
2674 if (sx->esmtp || sx->lmtp)
2675 {
2676 #ifdef EXPERIMENTAL_PIPE_CONNECT
2677 if (!sx->early_pipe_active)
2678 #endif
2679 {
2680 sx->peer_offered = ehlo_response(sx->buffer,
2681 0 /* no TLS */
2682 #ifdef EXPERIMENTAL_PIPE_CONNECT
2683 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2684 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2685 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2686 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2687
2688 #else
2689
2690 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2691 | OPTION_CHUNKING
2692 | OPTION_PRDR
2693 # ifdef SUPPORT_I18N
2694 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2695 /*XXX if we hand peercaps on to continued-conn processes,
2696 must not depend on this addr */
2697 # endif
2698 | OPTION_DSN
2699 | OPTION_PIPE
2700 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2701 #endif
2702 );
2703 #ifdef EXPERIMENTAL_PIPE_CONNECT
2704 if (tls_out.active.sock >= 0)
2705 sx->ehlo_resp.crypted_features = sx->peer_offered;
2706 #endif
2707 }
2708
2709 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2710 lmtp_ignore_quota option was set. */
2711
2712 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2713
2714 /* If the response to EHLO specified support for the SIZE parameter, note
2715 this, provided size_addition is non-negative. */
2716
2717 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2718
2719 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2720 the current host, esmtp will be false, so PIPELINING can never be used. If
2721 the current host matches hosts_avoid_pipelining, don't do it. */
2722
2723 if ( sx->peer_offered & OPTION_PIPE
2724 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2725 smtp_peer_options |= OPTION_PIPE;
2726
2727 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2728 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2729
2730 if ( sx->peer_offered & OPTION_CHUNKING
2731 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) != OK)
2732 sx->peer_offered &= ~OPTION_CHUNKING;
2733
2734 if (sx->peer_offered & OPTION_CHUNKING)
2735 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2736
2737 #ifndef DISABLE_PRDR
2738 if ( sx->peer_offered & OPTION_PRDR
2739 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) != OK)
2740 sx->peer_offered &= ~OPTION_PRDR;
2741
2742 if (sx->peer_offered & OPTION_PRDR)
2743 DEBUG(D_transport) debug_printf("PRDR usable\n");
2744 #endif
2745
2746 /* Note if the server supports DSN */
2747 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2748 DEBUG(D_transport) debug_printf("%susing DSN\n",
2749 sx->peer_offered & OPTION_DSN ? "" : "not ");
2750
2751 #ifdef EXPERIMENTAL_PIPE_CONNECT
2752 if ( sx->early_pipe_ok
2753 && !sx->early_pipe_active
2754 && tls_out.active.sock >= 0
2755 && smtp_peer_options & OPTION_PIPE
2756 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
2757 & OPTION_EARLY_PIPE)
2758 {
2759 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2760 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
2761 write_ehlo_cache_entry(sx);
2762 }
2763 #endif
2764
2765 /* Note if the response to EHLO specifies support for the AUTH extension.
2766 If it has, check that this host is one we want to authenticate to, and do
2767 the business. The host name and address must be available when the
2768 authenticator's client driver is running. */
2769
2770 switch (yield = smtp_auth(sx))
2771 {
2772 default: goto SEND_QUIT;
2773 case OK: break;
2774 case FAIL_SEND: goto SEND_FAILED;
2775 case FAIL: goto RESPONSE_FAILED;
2776 }
2777 }
2778 }
2779 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2780
2781 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2782 message-specific. */
2783
2784 sx->setting_up = FALSE;
2785
2786 #ifdef SUPPORT_I18N
2787 if (sx->addrlist->prop.utf8_msg)
2788 {
2789 uschar * s;
2790
2791 /* If the transport sets a downconversion mode it overrides any set by ACL
2792 for the message. */
2793
2794 if ((s = ob->utf8_downconvert))
2795 {
2796 if (!(s = expand_string(s)))
2797 {
2798 message = string_sprintf("failed to expand utf8_downconvert: %s",
2799 expand_string_message);
2800 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2801 yield = DEFER;
2802 goto SEND_QUIT;
2803 }
2804 switch (*s)
2805 {
2806 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
2807 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2808 break;
2809 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
2810 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2811 break;
2812 case '-': if (s[1] == '1')
2813 {
2814 sx->addrlist->prop.utf8_downcvt = FALSE;
2815 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
2816 }
2817 break;
2818 }
2819 }
2820
2821 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2822 && !sx->addrlist->prop.utf8_downcvt_maybe;
2823 DEBUG(D_transport) if (!sx->utf8_needed)
2824 debug_printf("utf8: %s downconvert\n",
2825 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2826 }
2827
2828 /* If this is an international message we need the host to speak SMTPUTF8 */
2829 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2830 {
2831 errno = ERRNO_UTF8_FWD;
2832 goto RESPONSE_FAILED;
2833 }
2834 #endif /*SUPPORT_I18N*/
2835
2836 return OK;
2837
2838
2839 {
2840 int code;
2841
2842 RESPONSE_FAILED:
2843 message = NULL;
2844 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
2845 sx->buffer, &code, &message, &pass_message);
2846 yield = DEFER;
2847 goto FAILED;
2848
2849 SEND_FAILED:
2850 code = '4';
2851 message = US string_sprintf("send() to %s [%s] failed: %s",
2852 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
2853 sx->send_quit = FALSE;
2854 yield = DEFER;
2855 goto FAILED;
2856
2857 EHLOHELO_FAILED:
2858 code = '4';
2859 message = string_sprintf("Remote host closed connection in response to %s"
2860 " (EHLO response was: %s)", smtp_command, sx->buffer);
2861 sx->send_quit = FALSE;
2862 yield = DEFER;
2863 goto FAILED;
2864
2865 /* This label is jumped to directly when a TLS negotiation has failed,
2866 or was not done for a host for which it is required. Values will be set
2867 in message and errno, and setting_up will always be true. Treat as
2868 a temporary error. */
2869
2870 #ifndef DISABLE_TLS
2871 TLS_FAILED:
2872 code = '4', yield = DEFER;
2873 goto FAILED;
2874 #endif
2875
2876 /* The failure happened while setting up the call; see if the failure was
2877 a 5xx response (this will either be on connection, or following HELO - a 5xx
2878 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2879 fail all addresses, as this host is never going to accept them. For other
2880 errors during setting up (timeouts or whatever), defer all addresses, and
2881 yield DEFER, so that the host is not tried again for a while.
2882
2883 XXX This peeking for another host feels like a layering violation. We want
2884 to note the host as unusable, but down here we shouldn't know if this was
2885 the last host to try for the addr(list). Perhaps the upper layer should be
2886 the one to do set_errno() ? The problem is that currently the addr is where
2887 errno etc. are stashed, but until we run out of hosts to try the errors are
2888 host-specific. Maybe we should enhance the host_item definition? */
2889
2890 FAILED:
2891 sx->ok = FALSE; /* For when reached by GOTO */
2892 set_errno(sx->addrlist, errno, message,
2893 sx->conn_args.host->next
2894 ? DEFER
2895 : code == '5'
2896 #ifdef SUPPORT_I18N
2897 || errno == ERRNO_UTF8_FWD
2898 #endif
2899 ? FAIL : DEFER,
2900 pass_message, sx->conn_args.host
2901 #ifdef EXPERIMENTAL_DSN_INFO
2902 , sx->smtp_greeting, sx->helo_response
2903 #endif
2904 );
2905 }
2906
2907
2908 SEND_QUIT:
2909
2910 if (sx->send_quit)
2911 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
2912
2913 #ifndef DISABLE_TLS
2914 if (sx->cctx.tls_ctx)
2915 {
2916 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
2917 sx->cctx.tls_ctx = NULL;
2918 }
2919 #endif
2920
2921 /* Close the socket, and return the appropriate value, first setting
2922 works because the NULL setting is passed back to the calling process, and
2923 remote_max_parallel is forced to 1 when delivering over an existing connection,
2924 */
2925
2926 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2927 if (sx->send_quit)
2928 {
2929 shutdown(sx->cctx.sock, SHUT_WR);
2930 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
2931 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
2932 i--; /* drain socket */
2933 sx->send_quit = FALSE;
2934 }
2935 (void)close(sx->cctx.sock);
2936 sx->cctx.sock = -1;
2937
2938 #ifndef DISABLE_EVENT
2939 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL);
2940 #endif
2941
2942 continue_transport = NULL;
2943 continue_hostname = NULL;
2944 return yield;
2945 }
2946
2947
2948
2949
2950 /* Create the string of options that will be appended to the MAIL FROM:
2951 in the connection context buffer */
2952
2953 static int
2954 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2955 {
2956 uschar * p = sx->buffer;
2957 address_item * addr;
2958 int address_count;
2959
2960 *p = 0;
2961
2962 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2963 send it, adding something to the message size to allow for imprecision
2964 and things that get added en route. Exim keeps the number of lines
2965 in a message, so we can give an accurate value for the original message, but we
2966 need some additional to handle added headers. (Double "." characters don't get
2967 included in the count.) */
2968
2969 if ( message_size > 0
2970 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
2971 {
2972 /*XXX problem here under spool_files_wireformat?
2973 Or just forget about lines? Or inflate by a fixed proportion? */
2974
2975 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
2976 while (*p) p++;
2977 }
2978
2979 #ifndef DISABLE_PRDR
2980 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
2981 request that */
2982
2983 sx->prdr_active = FALSE;
2984 if (sx->peer_offered & OPTION_PRDR)
2985 for (address_item * addr = addrlist; addr; addr = addr->next)
2986 if (addr->transport_return == PENDING_DEFER)
2987 {
2988 for (addr = addr->next; addr; addr = addr->next)
2989 if (addr->transport_return == PENDING_DEFER)
2990 { /* at least two recipients to send */
2991 sx->prdr_active = TRUE;
2992 sprintf(CS p, " PRDR"); p += 5;
2993 break;
2994 }
2995 break;
2996 }
2997 #endif
2998
2999 #ifdef SUPPORT_I18N
3000 /* If it supports internationalised messages, and this meesage need that,
3001 request it */
3002
3003 if ( sx->peer_offered & OPTION_UTF8
3004 && addrlist->prop.utf8_msg
3005 && !addrlist->prop.utf8_downcvt
3006 )
3007 Ustrcpy(p, " SMTPUTF8"), p += 9;
3008 #endif
3009
3010 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3011 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3012 addr && address_count < sx->max_rcpt;
3013 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3014 {
3015 address_count++;
3016 if (!(addr->dsn_flags & rf_dsnlasthop))
3017 {
3018 sx->dsn_all_lasthop = FALSE;
3019 break;
3020 }
3021 }
3022
3023 /* Add any DSN flags to the mail command */
3024
3025 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3026 {
3027 if (dsn_ret == dsn_ret_hdrs)
3028 { Ustrcpy(p, " RET=HDRS"); p += 9; }
3029 else if (dsn_ret == dsn_ret_full)
3030 { Ustrcpy(p, " RET=FULL"); p += 9; }
3031
3032 if (dsn_envid)
3033 {
3034 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3035 while (*p) p++;
3036 }
3037 }
3038
3039 /* If an authenticated_sender override has been specified for this transport
3040 instance, expand it. If the expansion is forced to fail, and there was already
3041 an authenticated_sender for this message, the original value will be used.
3042 Other expansion failures are serious. An empty result is ignored, but there is
3043 otherwise no check - this feature is expected to be used with LMTP and other
3044 cases where non-standard addresses (e.g. without domains) might be required. */
3045
3046 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->conn_args.ob))
3047 return ERROR;
3048
3049 return OK;
3050 }
3051
3052
3053 static void
3054 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3055 {
3056 uschar * p = sx->buffer;
3057 *p = 0;
3058
3059 /* Add any DSN flags to the rcpt command */
3060
3061 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3062 {
3063 if (addr->dsn_flags & rf_dsnflags)
3064 {
3065 BOOL first = TRUE;
3066
3067 Ustrcpy(p, " NOTIFY=");
3068 while (*p) p++;
3069 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3070 {
3071 if (!first) *p++ = ',';
3072 first = FALSE;
3073 Ustrcpy(p, rf_names[i]);
3074 while (*p) p++;
3075 }
3076 }
3077
3078 if (addr->dsn_orcpt)
3079 {
3080 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3081 addr->dsn_orcpt);
3082 while (*p) p++;
3083 }
3084 }
3085 }
3086
3087
3088
3089 /*
3090 Return:
3091 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3092 -1 MAIL response error
3093 -2 any non-MAIL read i/o error
3094 -3 non-MAIL response timeout
3095 -4 internal error; channel still usable
3096 -5 transmit failed
3097 */
3098
3099 int
3100 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3101 {
3102 address_item * addr;
3103 int address_count;
3104 int rc;
3105
3106 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3107 {
3108 *yield = ERROR;
3109 return -4;
3110 }
3111
3112 /* From here until we send the DATA command, we can make use of PIPELINING
3113 if the server host supports it. The code has to be able to check the responses
3114 at any point, for when the buffer fills up, so we write it totally generally.
3115 When PIPELINING is off, each command written reports that it has flushed the
3116 buffer. */
3117
3118 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3119
3120 {
3121 uschar * s = sx->from_addr;
3122 #ifdef SUPPORT_I18N
3123 uschar * errstr = NULL;
3124
3125 /* If we must downconvert, do the from-address here. Remember we had to
3126 for the to-addresses (done below), and also (ugly) for re-doing when building
3127 the delivery log line. */
3128
3129 if ( sx->addrlist->prop.utf8_msg
3130 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3131 )
3132 {
3133 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3134 {
3135 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
3136 *yield = ERROR;
3137 return -4;
3138 }
3139 setflag(sx->addrlist, af_utf8_downcvt);
3140 }
3141 #endif
3142
3143 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3144 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3145 }
3146
3147 mail_command = string_copy(big_buffer); /* Save for later error message */
3148
3149 switch(rc)
3150 {
3151 case -1: /* Transmission error */
3152 return -5;
3153
3154 case +1: /* Cmd was sent */
3155 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3156 (SOB sx->conn_args.ob)->command_timeout))
3157 {
3158 if (errno == 0 && sx->buffer[0] == '4')
3159 {
3160 errno = ERRNO_MAIL4XX;
3161 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3162 }
3163 return -1;
3164 }
3165 sx->pending_MAIL = FALSE;
3166 break;
3167
3168 /* otherwise zero: command queued for pipeline */
3169 }
3170
3171 /* Pass over all the relevant recipient addresses for this host, which are the
3172 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3173 several before we have to read the responses for those seen so far. This
3174 checking is done by a subroutine because it also needs to be done at the end.
3175 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3176 the next one if not all are sent.
3177
3178 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3179 last address because we want to abort if any recipients have any kind of
3180 problem, temporary or permanent. We know that all recipient addresses will have
3181 the PENDING_DEFER status, because only one attempt is ever made, and we know
3182 that max_rcpt will be large, so all addresses will be done at once.
3183
3184 For verify we flush the pipeline after any (the only) rcpt address. */
3185
3186 for (addr = sx->first_addr, address_count = 0;
3187 addr && address_count < sx->max_rcpt;
3188 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3189 {
3190 int count;
3191 BOOL no_flush;
3192 uschar * rcpt_addr;
3193
3194 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3195 ? dsn_support_yes : dsn_support_no;
3196
3197 address_count++;
3198 no_flush = pipelining_active && !sx->verify
3199 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3200
3201 build_rcptcmd_options(sx, addr);
3202
3203 /* Now send the RCPT command, and process outstanding responses when
3204 necessary. After a timeout on RCPT, we just end the function, leaving the
3205 yield as OK, because this error can often mean that there is a problem with
3206 just one address, so we don't want to delay the host. */
3207
3208 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3209
3210 #ifdef SUPPORT_I18N
3211 if ( testflag(sx->addrlist, af_utf8_downcvt)
3212 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3213 )
3214 {
3215 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3216 errno = ERRNO_EXPANDFAIL;
3217 return -5; /*XXX too harsh? */
3218 }
3219 #endif
3220
3221 count = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3222 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3223
3224 if (count < 0) return -5;
3225 if (count > 0)
3226 {
3227 switch(sync_responses(sx, count, 0))
3228 {
3229 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3230 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3231 break;
3232
3233 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3234 if (!sx->lmtp) /* can't tell about progress yet */
3235 sx->completed_addr = TRUE;
3236 case 0: /* No 2xx or 5xx, but no probs */
3237 break;
3238
3239 case -1: return -3; /* Timeout on RCPT */
3240 case -2: return -2; /* non-MAIL read i/o error */
3241 default: return -1; /* any MAIL error */
3242
3243 #ifdef EXPERIMENTAL_PIPE_CONNECT
3244 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3245 case -5: return -1; /* TLS first-read error */
3246 #endif
3247 }
3248 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
3249 }
3250 } /* Loop for next address */
3251
3252 sx->next_addr = addr;
3253 return 0;
3254 }
3255
3256
3257 #ifndef DISABLE_TLS
3258 /*****************************************************
3259 * Proxy TLS connection for another transport process *
3260 ******************************************************/
3261 /*
3262 Close the unused end of the pipe, fork once more, then use the given buffer
3263 as a staging area, and select on both the given fd and the TLS'd client-fd for
3264 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3265 Do blocking full-size writes, and reads under a timeout. Once both input
3266 channels are closed, exit the process.
3267
3268 Arguments:
3269 ct_ctx tls context
3270 buf space to use for buffering
3271 bufsiz size of buffer
3272 pfd pipe filedescriptor array; [0] is comms to proxied process
3273 timeout per-read timeout, seconds
3274 */
3275
3276 void
3277 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3278 int timeout)
3279 {
3280 fd_set rfds, efds;
3281 int max_fd = MAX(pfd[0], tls_out.active.sock) + 1;
3282 int rc, i;
3283
3284 close(pfd[1]);
3285 if ((rc = fork()))
3286 {
3287 DEBUG(D_transport) debug_printf("proxy-proc final-pid %d\n", rc);
3288 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3289 }
3290
3291 if (f.running_in_test_harness) millisleep(100); /* let parent debug out */
3292 set_process_info("proxying TLS connection for continued transport");
3293 FD_ZERO(&rfds);
3294 FD_SET(tls_out.active.sock, &rfds);
3295 FD_SET(pfd[0], &rfds);
3296
3297 for (int fd_bits = 3; fd_bits; )
3298 {
3299 time_t time_left = timeout;
3300 time_t time_start = time(NULL);
3301
3302 /* wait for data */
3303 efds = rfds;
3304 do
3305 {
3306 struct timeval tv = { time_left, 0 };
3307
3308 rc = select(max_fd,
3309 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
3310
3311 if (rc < 0 && errno == EINTR)
3312 if ((time_left -= time(NULL) - time_start) > 0) continue;
3313
3314 if (rc <= 0)
3315 {
3316 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3317 goto done;
3318 }
3319
3320 if (FD_ISSET(tls_out.active.sock, &efds) || FD_ISSET(pfd[0], &efds))
3321 {
3322 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3323 FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
3324 goto done;
3325 }
3326 }
3327 while (rc < 0 || !(FD_ISSET(tls_out.active.sock, &rfds) || FD_ISSET(pfd[0], &rfds)));
3328
3329 /* handle inbound data */
3330 if (FD_ISSET(tls_out.active.sock, &rfds))
3331 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0)
3332 {
3333 fd_bits &= ~1;
3334 FD_CLR(tls_out.active.sock, &rfds);
3335 shutdown(pfd[0], SHUT_WR);
3336 timeout = 5;
3337 }
3338 else
3339 {
3340 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3341 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3342 }
3343 else if (fd_bits & 1)
3344 FD_SET(tls_out.active.sock, &rfds);
3345
3346 /* handle outbound data */
3347 if (FD_ISSET(pfd[0], &rfds))
3348 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3349 {
3350 fd_bits = 0;
3351 tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3352 ct_ctx = NULL;
3353 }
3354 else
3355 {
3356 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3357 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3358 goto done;
3359 }
3360 else if (fd_bits & 2)
3361 FD_SET(pfd[0], &rfds);
3362 }
3363
3364 done:
3365 if (f.running_in_test_harness) millisleep(100); /* let logging complete */
3366 exim_exit(0, US"TLS proxy");
3367 }
3368 #endif
3369
3370
3371 /*************************************************
3372 * Deliver address list to given host *
3373 *************************************************/
3374
3375 /* If continue_hostname is not null, we get here only when continuing to
3376 deliver down an existing channel. The channel was passed as the standard
3377 input. TLS is never active on a passed channel; the previous process always
3378 closes it down before passing the connection on.
3379
3380 Otherwise, we have to make a connection to the remote host, and do the
3381 initial protocol exchange.
3382
3383 When running as an MUA wrapper, if the sender or any recipient is rejected,
3384 temporarily or permanently, we force failure for all recipients.
3385
3386 Arguments:
3387 addrlist chain of potential addresses to deliver; only those whose
3388 transport_return field is set to PENDING_DEFER are currently
3389 being processed; others should be skipped - they have either
3390 been delivered to an earlier host or IP address, or been
3391 failed by one of them.
3392 host host to deliver to
3393 host_af AF_INET or AF_INET6
3394 defport default TCP/IP port to use if host does not specify, in host
3395 byte order
3396 interface interface to bind to, or NULL
3397 tblock transport instance block
3398 message_defer set TRUE if yield is OK, but all addresses were deferred
3399 because of a non-recipient, non-host failure, that is, a
3400 4xx response to MAIL FROM, DATA, or ".". This is a defer
3401 that is specific to the message.
3402 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3403 a second attempt after TLS initialization fails
3404
3405 Returns: OK - the connection was made and the delivery attempted;
3406 the result for each address is in its data block.
3407 DEFER - the connection could not be made, or something failed
3408 while setting up the SMTP session, or there was a
3409 non-message-specific error, such as a timeout.
3410 ERROR - a filter command is specified for this transport,
3411 and there was a problem setting it up; OR helo_data
3412 or add_headers or authenticated_sender is specified
3413 for this transport, and the string failed to expand
3414 */
3415
3416 static int
3417 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3418 uschar *interface, transport_instance *tblock,
3419 BOOL *message_defer, BOOL suppress_tls)
3420 {
3421 smtp_transport_options_block * ob = SOB tblock->options_block;
3422 int yield = OK;
3423 int save_errno;
3424 int rc;
3425 struct timeval start_delivery_time;
3426
3427 BOOL pass_message = FALSE;
3428 uschar *message = NULL;
3429 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3430
3431 smtp_context sx;
3432
3433 gettimeofday(&start_delivery_time, NULL);
3434 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
3435 *message_defer = FALSE;
3436
3437 sx.addrlist = addrlist;
3438 sx.conn_args.host = host;
3439 sx.conn_args.host_af = host_af,
3440 sx.port = defport;
3441 sx.conn_args.interface = interface;
3442 sx.helo_data = NULL;
3443 sx.conn_args.tblock = tblock;
3444 sx.verify = FALSE;
3445 sx.sync_addr = sx.first_addr = addrlist;
3446
3447 /* Get the channel set up ready for a message (MAIL FROM being the next
3448 SMTP command to send */
3449
3450 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
3451 return rc;
3452
3453 /* If there is a filter command specified for this transport, we can now
3454 set it up. This cannot be done until the identify of the host is known. */
3455
3456 if (tblock->filter_command)
3457 {
3458 transport_filter_timeout = tblock->filter_timeout;
3459
3460 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3461 yield ERROR. */
3462
3463 if (!transport_set_up_command(&transport_filter_argv,
3464 tblock->filter_command, TRUE, DEFER, addrlist,
3465 string_sprintf("%.50s transport", tblock->name), NULL))
3466 {
3467 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3468 FALSE);
3469 yield = ERROR;
3470 goto SEND_QUIT;
3471 }
3472
3473 if ( transport_filter_argv
3474 && *transport_filter_argv
3475 && **transport_filter_argv
3476 && sx.peer_offered & OPTION_CHUNKING
3477 )
3478 {
3479 sx.peer_offered &= ~OPTION_CHUNKING;
3480 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3481 }
3482 }
3483
3484 /* For messages that have more than the maximum number of envelope recipients,
3485 we want to send several transactions down the same SMTP connection. (See
3486 comments in deliver.c as to how this reconciles, heuristically, with
3487 remote_max_parallel.) This optimization was added to Exim after the following
3488 code was already working. The simplest way to put it in without disturbing the
3489 code was to use a goto to jump back to this point when there is another
3490 transaction to handle. */
3491
3492 SEND_MESSAGE:
3493 sx.from_addr = return_path;
3494 sx.sync_addr = sx.first_addr;
3495 sx.ok = FALSE;
3496 sx.send_rset = TRUE;
3497 sx.completed_addr = FALSE;
3498
3499
3500 /* If we are a continued-connection-after-verify the MAIL and RCPT
3501 commands were already sent; do not re-send but do mark the addrs as
3502 having been accepted up to RCPT stage. A traditional cont-conn
3503 always has a sequence number greater than one. */
3504
3505 if (continue_hostname && continue_sequence == 1)
3506 {
3507 sx.peer_offered = smtp_peer_options;
3508 sx.pending_MAIL = FALSE;
3509 sx.ok = TRUE;
3510 sx.next_addr = NULL;
3511
3512 for (address_item * addr = addrlist; addr; addr = addr->next)
3513 addr->transport_return = PENDING_OK;
3514 }
3515 else
3516 {
3517 /* Initiate a message transfer. */
3518
3519 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
3520 {
3521 case 0: break;
3522 case -1: case -2: goto RESPONSE_FAILED;
3523 case -3: goto END_OFF;
3524 case -4: goto SEND_QUIT;
3525 default: goto SEND_FAILED;
3526 }
3527
3528 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3529 permanently or temporarily. We should have flushed and synced after the last
3530 RCPT. */
3531
3532 if (mua_wrapper)
3533 {
3534 address_item * a;
3535 unsigned cnt;
3536
3537 for (a = sx.first_addr, cnt = 0; a && cnt < sx.max_rcpt; a = a->next, cnt++)
3538 if (a->transport_return != PENDING_OK)
3539 {
3540 /*XXX could we find a better errno than 0 here? */
3541 set_errno_nohost(addrlist, 0, a->message, FAIL,
3542 testflag(a, af_pass_message));
3543 sx.ok = FALSE;
3544 break;
3545 }
3546 }
3547 }
3548
3549 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3550 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3551 have a good recipient buffered up if we are pipelining. We don't want to waste
3552 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3553 are pipelining. The responses are all handled by sync_responses().
3554 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3555 to send is. */
3556
3557 if ( !(sx.peer_offered & OPTION_CHUNKING)
3558 && (sx.ok || (pipelining_active && !mua_wrapper)))
3559 {
3560 int count = smtp_write_command(&sx, SCMD_FLUSH, "DATA\r\n");
3561
3562 if (count < 0) goto SEND_FAILED;
3563 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
3564 {
3565 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3566 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3567 break;
3568
3569 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3570 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3571 case 0: break; /* No 2xx or 5xx, but no probs */
3572
3573 case -1: goto END_OFF; /* Timeout on RCPT */
3574
3575 #ifdef EXPERIMENTAL_PIPE_CONNECT
3576 case -5: /* TLS first-read error */
3577 case -4: HDEBUG(D_transport)
3578 debug_printf("failed reaping pipelined cmd responses\n");
3579 #endif
3580 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3581 }
3582 pipelining_active = FALSE;
3583 data_command = string_copy(big_buffer); /* Save for later error message */
3584 }
3585
3586 /* If there were no good recipients (but otherwise there have been no
3587 problems), just set ok TRUE, since we have handled address-specific errors
3588 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3589 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3590 well as body. Set the appropriate timeout value to be used for each chunk.
3591 (Haven't been able to make it work using select() for writing yet.) */
3592
3593 if (!(sx.peer_offered & OPTION_CHUNKING) && !sx.ok)
3594 {
3595 /* Save the first address of the next batch. */
3596 sx.first_addr = sx.next_addr;
3597
3598 sx.ok = TRUE;
3599 }
3600 else
3601 {
3602 transport_ctx tctx = {
3603 .u = {.fd = sx.cctx.sock}, /*XXX will this need TLS info? */
3604 .tblock = tblock,
3605 .addr = addrlist,
3606 .check_string = US".",
3607 .escape_string = US"..", /* Escaping strings */
3608 .options =
3609 topt_use_crlf | topt_escape_headers
3610 | (tblock->body_only ? topt_no_headers : 0)
3611 | (tblock->headers_only ? topt_no_body : 0)
3612 | (tblock->return_path_add ? topt_add_return_path : 0)
3613 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3614 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3615 };
3616
3617 /* If using CHUNKING we need a callback from the generic transport
3618 support to us, for the sending of BDAT smtp commands and the reaping
3619 of responses. The callback needs a whole bunch of state so set up
3620 a transport-context structure to be passed around. */
3621
3622 if (sx.peer_offered & OPTION_CHUNKING)
3623 {
3624 tctx.check_string = tctx.escape_string = NULL;
3625 tctx.options |= topt_use_bdat;
3626 tctx.chunk_cb = smtp_chunk_cmd_callback;
3627 sx.pending_BDAT = FALSE;
3628 sx.good_RCPT = sx.ok;
3629 sx.cmd_count = 0;
3630 tctx.smtp_context = &sx;
3631 }
3632 else
3633 tctx.options |= topt_end_dot;
3634
3635 /* Save the first address of the next batch. */
3636 sx.first_addr = sx.next_addr;
3637
3638 /* Responses from CHUNKING commands go in buffer. Otherwise,
3639 there has not been a response. */
3640
3641 sx.buffer[0] = 0;
3642
3643 sigalrm_seen = FALSE;
3644 transport_write_timeout = ob->data_timeout;
3645 smtp_command = US"sending data block"; /* For error messages */
3646 DEBUG(D_transport|D_v)
3647 if (sx.peer_offered & OPTION_CHUNKING)
3648 debug_printf(" will write message using CHUNKING\n");
3649 else
3650 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3651 transport_count = 0;
3652
3653 #ifndef DISABLE_DKIM
3654 dkim_exim_sign_init();
3655 # ifdef EXPERIMENTAL_ARC
3656 {
3657 uschar * s = ob->arc_sign;
3658 if (s)
3659 {
3660 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
3661 {
3662 if (!f.expand_string_forcedfail)
3663 {
3664 message = US"failed to expand arc_sign";
3665 sx.ok = FALSE;
3666 goto SEND_FAILED;
3667 }
3668 }
3669 else if (*s)
3670 {
3671 /* Ask dkim code to hash the body for ARC */
3672 (void) arc_ams_setup_sign_bodyhash();
3673 ob->dkim.force_bodyhash = TRUE;
3674 }
3675 }
3676 }
3677 # endif
3678 sx.ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
3679 #else
3680 sx.ok = transport_write_message(&tctx, 0);
3681 #endif
3682
3683 /* transport_write_message() uses write() because it is called from other
3684 places to write to non-sockets. This means that under some OS (e.g. Solaris)
3685 it can exit with "Broken pipe" as its error. This really means that the
3686 socket got closed at the far end. */
3687
3688 transport_write_timeout = 0; /* for subsequent transports */
3689
3690 /* Failure can either be some kind of I/O disaster (including timeout),
3691 or the failure of a transport filter or the expansion of added headers.
3692 Or, when CHUNKING, it can be a protocol-detected failure. */
3693
3694 if (!sx.ok)
3695 if (message) goto SEND_FAILED;
3696 else goto RESPONSE_FAILED;
3697
3698 /* We used to send the terminating "." explicitly here, but because of
3699 buffering effects at both ends of TCP/IP connections, you don't gain
3700 anything by keeping it separate, so it might as well go in the final
3701 data buffer for efficiency. This is now done by setting the topt_end_dot
3702 flag above. */
3703
3704 smtp_command = US"end of data";
3705
3706 if (sx.peer_offered & OPTION_CHUNKING && sx.cmd_count > 1)
3707 {
3708 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
3709 switch(sync_responses(&sx, sx.cmd_count-1, 0))
3710 {
3711 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
3712 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
3713 break;
3714
3715 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3716 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
3717 case 0: break; /* No 2xx or 5xx, but no probs */
3718
3719 case -1: goto END_OFF; /* Timeout on RCPT */
3720
3721 #ifdef EXPERIMENTAL_PIPE_CONNECT
3722 case -5: /* TLS first-read error */
3723 case -4: HDEBUG(D_transport)
3724 debug_printf("failed reaping pipelined cmd responses\n");
3725 #endif
3726 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3727 }
3728 }
3729
3730 #ifndef DISABLE_PRDR
3731 /* For PRDR we optionally get a partial-responses warning followed by the
3732 individual responses, before going on with the overall response. If we don't
3733 get the warning then deal with per non-PRDR. */
3734
3735 if(sx.prdr_active)
3736 {
3737 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '3', ob->final_timeout);
3738 if (!sx.ok && errno == 0) switch(sx.buffer[0])
3739 {
3740 case '2': sx.prdr_active = FALSE;
3741 sx.ok = TRUE;
3742 break;
3743 case '4': errno = ERRNO_DATA4XX;
3744 addrlist->more_errno |=
3745 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3746 break;
3747 }
3748 }
3749 else
3750 #endif
3751
3752 /* For non-PRDR SMTP, we now read a single response that applies to the
3753 whole message. If it is OK, then all the addresses have been delivered. */
3754
3755 if (!sx.lmtp)
3756 {
3757 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3758 ob->final_timeout);
3759 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
3760 {
3761 errno = ERRNO_DATA4XX;
3762 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3763 }
3764 }
3765
3766 /* For LMTP, we get back a response for every RCPT command that we sent;
3767 some may be accepted and some rejected. For those that get a response, their
3768 status is fixed; any that are accepted have been handed over, even if later
3769 responses crash - at least, that's how I read RFC 2033.
3770
3771 If all went well, mark the recipient addresses as completed, record which
3772 host/IPaddress they were delivered to, and cut out RSET when sending another
3773 message down the same channel. Write the completed addresses to the journal
3774 now so that they are recorded in case there is a crash of hardware or
3775 software before the spool gets updated. Also record the final SMTP
3776 confirmation if needed (for SMTP only). */
3777
3778 if (sx.ok)
3779 {
3780 int flag = '=';
3781 struct timeval delivery_time;
3782 int len;
3783 uschar * conf = NULL;
3784
3785 timesince(&delivery_time, &start_delivery_time);
3786 sx.send_rset = FALSE;
3787 pipelining_active = FALSE;
3788
3789 /* Set up confirmation if needed - applies only to SMTP */
3790
3791 if (
3792 #ifdef DISABLE_EVENT
3793 LOGGING(smtp_confirmation) &&
3794 #endif
3795 !sx.lmtp
3796 )
3797 {
3798 const uschar *s = string_printing(sx.buffer);
3799 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3800 conf = (s == sx.buffer)? US string_copy(s) : US s;
3801 }
3802
3803 /* Process all transported addresses - for LMTP or PRDR, read a status for
3804 each one. */
3805
3806 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3807 {
3808 if (addr->transport_return != PENDING_OK) continue;
3809
3810 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3811 remaining addresses. Otherwise, it's a return code for just the one
3812 address. For temporary errors, add a retry item for the address so that
3813 it doesn't get tried again too soon. */
3814
3815 #ifndef DISABLE_PRDR
3816 if (sx.lmtp || sx.prdr_active)
3817 #else
3818 if (sx.lmtp)
3819 #endif
3820 {
3821 if (!smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3822 ob->final_timeout))
3823 {
3824 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3825 addr->message = string_sprintf(
3826 #ifndef DISABLE_PRDR
3827 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3828 #else
3829 "LMTP error after %s: %s",
3830 #endif
3831 data_command, string_printing(sx.buffer));
3832 setflag(addr, af_pass_message); /* Allow message to go to user */
3833 if (sx.buffer[0] == '5')
3834 addr->transport_return = FAIL;
3835 else
3836 {
3837 errno = ERRNO_DATA4XX;
3838 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3839 addr->transport_return = DEFER;
3840 #ifndef DISABLE_PRDR
3841 if (!sx.prdr_active)
3842 #endif
3843 retry_add_item(addr, addr->address_retry_key, 0);
3844 }
3845 continue;
3846 }
3847 sx.completed_addr = TRUE; /* NOW we can set this flag */
3848 if (LOGGING(smtp_confirmation))
3849 {
3850 const uschar *s = string_printing(sx.buffer);
3851 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3852 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3853 }
3854 }
3855
3856 /* SMTP, or success return from LMTP for this address. Pass back the
3857 actual host that was used. */
3858
3859 addr->transport_return = OK;
3860 addr->more_errno = delivery_time.tv_sec;
3861 addr->delivery_usec = delivery_time.tv_usec;
3862 addr->host_used = host;
3863 addr->special_action = flag;
3864 addr->message = conf;
3865
3866 if (tcp_out_fastopen)
3867 {
3868 setflag(addr, af_tcp_fastopen_conn);
3869 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
3870 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
3871 }
3872 if (sx.pipelining_used) setflag(addr, af_pipelining);
3873 #ifdef EXPERIMENTAL_PIPE_CONNECT
3874 if (sx.early_pipe_active) setflag(addr, af_early_pipe);
3875 #endif
3876 #ifndef DISABLE_PRDR
3877 if (sx.prdr_active) setflag(addr, af_prdr_used);
3878 #endif
3879 if (sx.peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
3880 flag = '-';
3881
3882 #ifndef DISABLE_PRDR
3883 if (!sx.prdr_active)
3884 #endif
3885 {
3886 /* Update the journal. For homonymic addresses, use the base address plus
3887 the transport name. See lots of comments in deliver.c about the reasons
3888 for the complications when homonyms are involved. Just carry on after
3889 write error, as it may prove possible to update the spool file later. */
3890
3891 if (testflag(addr, af_homonym))
3892 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3893 else
3894 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3895
3896 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3897 len = Ustrlen(CS sx.buffer);
3898 if (write(journal_fd, sx.buffer, len) != len)
3899 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3900 "%s: %s", sx.buffer, strerror(errno));
3901 }
3902 }
3903
3904 #ifndef DISABLE_PRDR
3905 if (sx.prdr_active)
3906 {
3907 const uschar * overall_message;
3908
3909 /* PRDR - get the final, overall response. For any non-success
3910 upgrade all the address statuses. */
3911
3912 sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2',
3913 ob->final_timeout);
3914 if (!sx.ok)
3915 {
3916 if(errno == 0 && sx.buffer[0] == '4')
3917 {
3918 errno = ERRNO_DATA4XX;
3919 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3920 }
3921 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3922 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3923 addr->transport_return = PENDING_OK; /* allow set_errno action */
3924 goto RESPONSE_FAILED;
3925 }
3926
3927 /* Append the overall response to the individual PRDR response for logging
3928 and update the journal, or setup retry. */
3929
3930 overall_message = string_printing(sx.buffer);
3931 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3932 if (addr->transport_return == OK)
3933 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
3934
3935 for (address_item * addr = addrlist; addr != sx.first_addr; addr = addr->next)
3936 if (addr->transport_return == OK)
3937 {
3938 if (testflag(addr, af_homonym))
3939 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3940 else
3941 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3942
3943 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3944 len = Ustrlen(CS sx.buffer);
3945 if (write(journal_fd, sx.buffer, len) != len)
3946 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3947 "%s: %s", sx.buffer, strerror(errno));
3948 }
3949 else if (addr->transport_return == DEFER)
3950 retry_add_item(addr, addr->address_retry_key, -2);
3951 }
3952 #endif
3953
3954 /* Ensure the journal file is pushed out to disk. */
3955
3956 if (EXIMfsync(journal_fd) < 0)
3957 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3958 strerror(errno));
3959 }
3960 }
3961
3962
3963 /* Handle general (not specific to one address) failures here. The value of ok
3964 is used to skip over this code on the falling through case. A timeout causes a
3965 deferral. Other errors may defer or fail according to the response code, and
3966 may set up a special errno value, e.g. after connection chopped, which is
3967 assumed if errno == 0 and there is no text in the buffer. If control reaches
3968 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3969 the problem is not related to this specific message. */
3970
3971 if (!sx.ok)
3972 {
3973 int code, set_rc;
3974 uschar * set_message;
3975
3976 RESPONSE_FAILED:
3977 {
3978 save_errno = errno;
3979 message = NULL;
3980 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3981 sx.buffer, &code, &message, &pass_message);
3982 goto FAILED;
3983 }
3984
3985 SEND_FAILED:
3986 {
3987 save_errno = errno;
3988 code = '4';
3989 message = string_sprintf("send() to %s [%s] failed: %s",
3990 host->name, host->address, message ? message : US strerror(save_errno));
3991 sx.send_quit = FALSE;
3992 goto FAILED;
3993 }
3994
3995 FAILED:
3996 {
3997 BOOL message_error;
3998
3999 sx.ok = FALSE; /* For when reached by GOTO */
4000 set_message = message;
4001
4002 /* We want to handle timeouts after MAIL or "." and loss of connection after
4003 "." specially. They can indicate a problem with the sender address or with
4004 the contents of the message rather than a real error on the connection. These
4005 cases are treated in the same way as a 4xx response. This next bit of code
4006 does the classification. */
4007
4008 switch(save_errno)
4009 {
4010 case 0:
4011 case ERRNO_MAIL4XX:
4012 case ERRNO_DATA4XX:
4013 message_error = TRUE;
4014 break;
4015
4016 case ETIMEDOUT:
4017 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4018 Ustrncmp(smtp_command,"end ",4) == 0;
4019 break;
4020
4021 case ERRNO_SMTPCLOSED:
4022 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4023 break;
4024
4025 default:
4026 message_error = FALSE;
4027 break;
4028 }
4029
4030 /* Handle the cases that are treated as message errors. These are:
4031
4032 (a) negative response or timeout after MAIL
4033 (b) negative response after DATA
4034 (c) negative response or timeout or dropped connection after "."
4035 (d) utf8 support required and not offered
4036
4037 It won't be a negative response or timeout after RCPT, as that is dealt
4038 with separately above. The action in all cases is to set an appropriate
4039 error code for all the addresses, but to leave yield set to OK because the
4040 host itself has not failed. Of course, it might in practice have failed
4041 when we've had a timeout, but if so, we'll discover that at the next
4042 delivery attempt. For a temporary error, set the message_defer flag, and
4043 write to the logs for information if this is not the last host. The error
4044 for the last host will be logged as part of the address's log line. */
4045
4046 if (message_error)
4047 {
4048 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4049
4050 /* If there's an errno, the message contains just the identity of
4051 the host. */
4052
4053 if (code == '5')
4054 set_rc = FAIL;
4055 else /* Anything other than 5 is treated as temporary */
4056 {
4057 set_rc = DEFER;
4058 if (save_errno > 0)
4059 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4060
4061 write_logs(host, message, sx.first_addr ? sx.first_addr->basic_errno : 0);
4062
4063 *message_defer = TRUE;
4064 }
4065 }
4066
4067 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4068 ".", or some other transportation error. We defer all addresses and yield
4069 DEFER, except for the case of failed add_headers expansion, or a transport
4070 filter failure, when the yield should be ERROR, to stop it trying other
4071 hosts. */
4072
4073 else
4074 {
4075 #ifdef EXPERIMENTAL_PIPE_CONNECT
4076 /* If we were early-pipelinng and the actual EHLO response did not match
4077 the cached value we assumed, we could have detected it and passed a
4078 custom errno through to here. It would be nice to RSET and retry right
4079 away, but to reliably do that we eould need an extra synch point before
4080 we committed to data and that would discard half the gained roundrips.
4081 Or we could summarily drop the TCP connection. but that is also ugly.
4082 Instead, we ignore the possibility (having freshened the cache) and rely
4083 on the server telling us with a nonmessage error if we have tried to
4084 do something it no longer supports. */
4085 #endif
4086 set_rc = DEFER;
4087 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4088 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4089 }
4090 }
4091
4092 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
4093 #ifdef EXPERIMENTAL_DSN_INFO
4094 , sx.smtp_greeting, sx.helo_response
4095 #endif
4096 );
4097 }
4098
4099
4100 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4101 SMTP session tidily. However, if there were too many addresses to send in one
4102 message (indicated by first_addr being non-NULL) we want to carry on with the
4103 rest of them. Also, it is desirable to send more than one message down the SMTP
4104 connection if there are several waiting, provided we haven't already sent so
4105 many as to hit the configured limit. The function transport_check_waiting looks
4106 for a waiting message and returns its id. Then transport_pass_socket tries to
4107 set up a continued delivery by passing the socket on to another process. The
4108 variable send_rset is FALSE if a message has just been successfully transferred.
4109
4110 If we are already sending down a continued channel, there may be further
4111 addresses not yet delivered that are aimed at the same host, but which have not
4112 been passed in this run of the transport. In this case, continue_more will be
4113 true, and all we should do is send RSET if necessary, and return, leaving the
4114 channel open.
4115
4116 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4117 do not want to continue with other messages down the same channel, because that
4118 can lead to looping between two or more messages, all with the same,
4119 temporarily failing address(es). [The retry information isn't updated yet, so
4120 new processes keep on trying.] We probably also don't want to try more of this
4121 message's addresses either.
4122
4123 If we have started a TLS session, we have to end it before passing the
4124 connection to a new process. However, not all servers can handle this (Exim
4125 can), so we do not pass such a connection on if the host matches
4126 hosts_nopass_tls. */
4127
4128 DEBUG(D_transport)
4129 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4130 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
4131 sx.send_rset, f.continue_more, yield, sx.first_addr ? "not " : "");
4132
4133 if (sx.completed_addr && sx.ok && sx.send_quit)
4134 {
4135 BOOL more;
4136 smtp_compare_t t_compare;
4137
4138 t_compare.tblock = tblock;
4139 t_compare.current_sender_address = sender_address;
4140
4141 if ( sx.first_addr != NULL
4142 || f.continue_more
4143 || (
4144 #ifndef DISABLE_TLS
4145 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4146 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4147 )
4148 &&
4149 #endif
4150 transport_check_waiting(tblock->name, host->name,
4151 tblock->connection_max_messages, new_message_id, &more,
4152 (oicf)smtp_are_same_identities, (void*)&t_compare)
4153 ) )
4154 {
4155 uschar *msg;
4156 BOOL pass_message;
4157
4158 if (sx.send_rset)
4159 if (! (sx.ok = smtp_write_command(&sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4160 {
4161 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
4162 host->address, strerror(errno));
4163 sx.send_quit = FALSE;
4164 }
4165 else if (! (sx.ok = smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer),
4166 '2', ob->command_timeout)))
4167 {
4168 int code;
4169 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
4170 &pass_message);
4171 if (!sx.send_quit)
4172 {
4173 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4174 host->name, host->address, msg);
4175 }
4176 }
4177
4178 /* Either RSET was not needed, or it succeeded */
4179
4180 if (sx.ok)
4181 {
4182 #ifndef DISABLE_TLS
4183 int pfd[2];
4184 #endif
4185 int socket_fd = sx.cctx.sock;
4186
4187
4188 if (sx.first_addr != NULL) /* More addresses still to be sent */
4189 { /* in this run of the transport */
4190 continue_sequence++; /* Causes * in logging */
4191 goto SEND_MESSAGE;
4192 }
4193
4194 /* Unless caller said it already has more messages listed for this host,
4195 pass the connection on to a new Exim process (below, the call to
4196 transport_pass_socket). If the caller has more ready, just return with
4197 the connection still open. */
4198
4199 #ifndef DISABLE_TLS
4200 if (tls_out.active.sock >= 0)
4201 if ( f.continue_more
4202 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4203 {
4204 /* Before passing the socket on, or returning to caller with it still
4205 open, we must shut down TLS. Not all MTAs allow for the continuation
4206 of the SMTP session when TLS is shut down. We test for this by sending
4207 a new EHLO. If we don't get a good response, we don't attempt to pass
4208 the socket on. */
4209
4210 tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4211 sx.cctx.tls_ctx = NULL;
4212 smtp_peer_options = smtp_peer_options_wrap;
4213 sx.ok = !sx.smtps
4214 && smtp_write_command(&sx, SCMD_FLUSH, "EHLO %s\r\n", sx.helo_data)
4215 >= 0
4216 && smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer),
4217 '2', ob->command_timeout);
4218
4219 if (sx.ok && f.continue_more)
4220 return yield; /* More addresses for another run */
4221 }
4222 else
4223 {
4224 /* Set up a pipe for proxying TLS for the new transport process */
4225
4226 smtp_peer_options |= OPTION_TLS;
4227 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4228 socket_fd = pfd[1];
4229 else
4230 set_errno(sx.first_addr, errno, US"internal allocation problem",
4231 DEFER, FALSE, host
4232 # ifdef EXPERIMENTAL_DSN_INFO
4233 , sx.smtp_greeting, sx.helo_response
4234 # endif
4235 );
4236 }
4237 else
4238 #endif
4239 if (f.continue_more)
4240 return yield; /* More addresses for another run */
4241
4242 /* If the socket is successfully passed, we mustn't send QUIT (or
4243 indeed anything!) from here. */
4244
4245 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4246 propagate it from the initial
4247 */
4248 if (sx.ok && transport_pass_socket(tblock->name, host->name,
4249 host->address, new_message_id, socket_fd))
4250 {
4251 sx.send_quit = FALSE;
4252
4253 /* We have passed the client socket to a fresh transport process.
4254 If TLS is still active, we need to proxy it for the transport we
4255 just passed the baton to. Fork a child to to do it, and return to
4256 get logging done asap. Which way to place the work makes assumptions
4257 about post-fork prioritisation which may not hold on all platforms. */
4258 #ifndef DISABLE_TLS
4259 if (tls_out.active.sock >= 0)
4260 {
4261 int pid = fork();
4262 if (pid == 0) /* child; fork again to disconnect totally */
4263 {
4264 if (f.running_in_test_harness) millisleep(100); /* let parent debug out */
4265 /* does not return */
4266 smtp_proxy_tls(sx.cctx.tls_ctx, sx.buffer, sizeof(sx.buffer), pfd,
4267 ob->command_timeout);
4268 }
4269
4270 if (pid > 0) /* parent */
4271 {
4272 DEBUG(D_transport) debug_printf("proxy-proc inter-pid %d\n", pid);
4273 close(pfd[0]);
4274 /* tidy the inter-proc to disconn the proxy proc */
4275 waitpid(pid, NULL, 0);
4276 tls_close(sx.cctx.tls_ctx, TLS_NO_SHUTDOWN);
4277 sx.cctx.tls_ctx = NULL;
4278 (void)close(sx.cctx.sock);
4279 sx.cctx.sock = -1;
4280 continue_transport = NULL;
4281 continue_hostname = NULL;
4282 return yield;
4283 }
4284 log_write(0, LOG_PANIC_DIE, "fork failed");
4285 }
4286 #endif
4287 }
4288 }
4289
4290 /* If RSET failed and there are addresses left, they get deferred. */
4291 else
4292 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
4293 #ifdef EXPERIMENTAL_DSN_INFO
4294 , sx.smtp_greeting, sx.helo_response
4295 #endif
4296 );
4297 }
4298 }
4299
4300 /* End off tidily with QUIT unless the connection has died or the socket has
4301 been passed to another process. There has been discussion on the net about what
4302 to do after sending QUIT. The wording of the RFC suggests that it is necessary
4303 to wait for a response, but on the other hand, there isn't anything one can do
4304 with an error response, other than log it. Exim used to do that. However,
4305 further discussion suggested that it is positively advantageous not to wait for
4306 the response, but to close the session immediately. This is supposed to move
4307 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
4308 load from the server. (Hosts that are both servers and clients may not see much
4309 difference, of course.) Further discussion indicated that this was safe to do
4310 on Unix systems which have decent implementations of TCP/IP that leave the
4311 connection around for a while (TIME_WAIT) after the application has gone away.
4312 This enables the response sent by the server to be properly ACKed rather than
4313 timed out, as can happen on broken TCP/IP implementations on other OS.
4314
4315 This change is being made on 31-Jul-98. After over a year of trouble-free
4316 operation, the old commented-out code was removed on 17-Sep-99. */
4317
4318 SEND_QUIT:
4319 #ifdef TCP_CORK
4320 (void) setsockopt(sx.cctx.sock, IPPROTO_TCP, TCP_CORK, US &on, sizeof(on));
4321 #endif
4322 if (sx.send_quit) (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4323
4324 END_OFF:
4325
4326 #ifndef DISABLE_TLS
4327 tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
4328 sx.cctx.tls_ctx = NULL;
4329 #endif
4330
4331 /* Close the socket, and return the appropriate value, first setting
4332 works because the NULL setting is passed back to the calling process, and
4333 remote_max_parallel is forced to 1 when delivering over an existing connection,
4334
4335 If all went well and continue_more is set, we shouldn't actually get here if
4336 there are further addresses, as the return above will be taken. However,
4337 writing RSET might have failed, or there may be other addresses whose hosts are
4338 specified in the transports, and therefore not visible at top level, in which
4339 case continue_more won't get set. */
4340
4341 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4342 if (sx.send_quit)
4343 {
4344 shutdown(sx.cctx.sock, SHUT_WR);
4345 millisleep(f.running_in_test_harness ? 200 : 20);
4346 if (fcntl(sx.cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4347 for (int i = 16; read(sx.cctx.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && i > 0;)
4348 i--; /* drain socket */
4349 }
4350 (void)close(sx.cctx.sock);
4351
4352 #ifndef DISABLE_EVENT
4353 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
4354 #endif
4355
4356 continue_transport = NULL;
4357 continue_hostname = NULL;
4358 return yield;
4359 }
4360
4361
4362
4363
4364 /*************************************************
4365 * Closedown entry point *
4366 *************************************************/
4367
4368 /* This function is called when exim is passed an open smtp channel
4369 from another incarnation, but the message which it has been asked
4370 to deliver no longer exists. The channel is on stdin.
4371
4372 We might do fancy things like looking for another message to send down
4373 the channel, but if the one we sought has gone, it has probably been
4374 delivered by some other process that itself will seek further messages,
4375 so just close down our connection.
4376
4377 Argument: pointer to the transport instance block
4378 Returns: nothing
4379 */
4380
4381 void
4382 smtp_transport_closedown(transport_instance *tblock)
4383 {
4384 smtp_transport_options_block * ob = SOB tblock->options_block;
4385 client_conn_ctx cctx;
4386 smtp_context sx;
4387 uschar buffer[256];
4388 uschar inbuffer[4096];
4389 uschar outbuffer[16];
4390
4391 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4392 cctx.sock = fileno(stdin);
4393 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4394
4395 sx.inblock.cctx = &cctx;
4396 sx.inblock.buffer = inbuffer;
4397 sx.inblock.buffersize = sizeof(inbuffer);
4398 sx.inblock.ptr = inbuffer;
4399 sx.inblock.ptrend = inbuffer;
4400
4401 sx.outblock.cctx = &cctx;
4402 sx.outblock.buffersize = sizeof(outbuffer);
4403 sx.outblock.buffer = outbuffer;
4404 sx.outblock.ptr = outbuffer;
4405 sx.outblock.cmd_count = 0;
4406 sx.outblock.authenticating = FALSE;
4407
4408 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4409 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
4410 (void)close(cctx.sock);
4411 }
4412
4413
4414
4415 /*************************************************
4416 * Prepare addresses for delivery *
4417 *************************************************/
4418
4419 /* This function is called to flush out error settings from previous delivery
4420 attempts to other hosts. It also records whether we got here via an MX record
4421 or not in the more_errno field of the address. We are interested only in
4422 addresses that are still marked DEFER - others may have got delivered to a
4423 previously considered IP address. Set their status to PENDING_DEFER to indicate
4424 which ones are relevant this time.
4425
4426 Arguments:
4427 addrlist the list of addresses
4428 host the host we are delivering to
4429
4430 Returns: the first address for this delivery
4431 */
4432
4433 static address_item *
4434 prepare_addresses(address_item *addrlist, host_item *host)
4435 {
4436 address_item *first_addr = NULL;
4437 for (address_item * addr = addrlist; addr; addr = addr->next)
4438 if (addr->transport_return == DEFER)
4439 {
4440 if (!first_addr) first_addr = addr;
4441 addr->transport_return = PENDING_DEFER;
4442 addr->basic_errno = 0;
4443 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
4444 addr->message = NULL;
4445 #ifndef DISABLE_TLS
4446 addr->cipher = NULL;
4447 addr->ourcert = NULL;
4448 addr->peercert = NULL;
4449 addr->peerdn = NULL;
4450 addr->ocsp = OCSP_NOT_REQ;
4451 #endif
4452 #ifdef EXPERIMENTAL_DSN_INFO
4453 addr->smtp_greeting = NULL;
4454 addr->helo_response = NULL;
4455 #endif
4456 }
4457 return first_addr;
4458 }
4459
4460
4461
4462 /*************************************************
4463 * Main entry point *
4464 *************************************************/
4465
4466 /* See local README for interface details. As this is a remote transport, it is
4467 given a chain of addresses to be delivered in one connection, if possible. It
4468 always returns TRUE, indicating that each address has its own independent
4469 status set, except if there is a setting up problem, in which case it returns
4470 FALSE. */
4471
4472 BOOL
4473 smtp_transport_entry(
4474 transport_instance *tblock, /* data for this instantiation */
4475 address_item *addrlist) /* addresses we are working on */
4476 {
4477 int defport;
4478 int hosts_defer = 0;
4479 int hosts_fail = 0;
4480 int hosts_looked_up = 0;
4481 int hosts_retry = 0;
4482 int hosts_serial = 0;
4483 int hosts_total = 0;
4484 int total_hosts_tried = 0;
4485 BOOL expired = TRUE;
4486 uschar *expanded_hosts = NULL;
4487 uschar *pistring;
4488 uschar *tid = string_sprintf("%s transport", tblock->name);
4489 smtp_transport_options_block *ob = SOB tblock->options_block;
4490 host_item *hostlist = addrlist->host_list;
4491 host_item *host = NULL;
4492
4493 DEBUG(D_transport)
4494 {
4495 debug_printf("%s transport entered\n", tblock->name);
4496 for (address_item * addr = addrlist; addr; addr = addr->next)
4497 debug_printf(" %s\n", addr->address);
4498 if (hostlist)
4499 {
4500 debug_printf("hostlist:\n");
4501 for (host_item * host = hostlist; host; host = host->next)
4502 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
4503 }
4504 if (continue_hostname)
4505 debug_printf("already connected to %s [%s] (on fd %d)\n",
4506 continue_hostname, continue_host_address,
4507 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
4508 }
4509
4510 /* Set the flag requesting that these hosts be added to the waiting
4511 database if the delivery fails temporarily or if we are running with
4512 queue_smtp or a 2-stage queue run. This gets unset for certain
4513 kinds of error, typically those that are specific to the message. */
4514
4515 update_waiting = TRUE;
4516
4517 /* If a host list is not defined for the addresses - they must all have the
4518 same one in order to be passed to a single transport - or if the transport has
4519 a host list with hosts_override set, use the host list supplied with the
4520 transport. It is an error for this not to exist. */
4521
4522 if (!hostlist || (ob->hosts_override && ob->hosts))
4523 {
4524 if (!ob->hosts)
4525 {
4526 addrlist->message = string_sprintf("%s transport called with no hosts set",
4527 tblock->name);
4528 addrlist->transport_return = PANIC;
4529 return FALSE; /* Only top address has status */
4530 }
4531
4532 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
4533 ob->hosts);
4534
4535 /* If the transport's host list contains no '$' characters, and we are not
4536 randomizing, it is fixed and therefore a chain of hosts can be built once
4537 and for all, and remembered for subsequent use by other calls to this
4538 transport. If, on the other hand, the host list does contain '$', or we are
4539 randomizing its order, we have to rebuild it each time. In the fixed case,
4540 as the hosts string will never be used again, it doesn't matter that we
4541 replace all the : characters with zeros. */
4542
4543 if (!ob->hostlist)
4544 {
4545 uschar *s = ob->hosts;
4546
4547 if (Ustrchr(s, '$') != NULL)
4548 {
4549 if (!(expanded_hosts = expand_string(s)))
4550 {
4551 addrlist->message = string_sprintf("failed to expand list of hosts "
4552 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
4553 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
4554 return FALSE; /* Only top address has status */
4555 }
4556 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
4557 "\"%s\"\n", s, expanded_hosts);
4558 s = expanded_hosts;
4559 }
4560 else
4561 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
4562
4563 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
4564
4565 /* Check that the expansion yielded something useful. */
4566 if (!hostlist)
4567 {
4568 addrlist->message =
4569 string_sprintf("%s transport has empty hosts setting", tblock->name);
4570 addrlist->transport_return = PANIC;
4571 return FALSE; /* Only top address has status */
4572 }
4573
4574 /* If there was no expansion of hosts, save the host list for
4575 next time. */
4576
4577 if (!expanded_hosts) ob->hostlist = hostlist;
4578 }
4579
4580 /* This is not the first time this transport has been run in this delivery;
4581 the host list was built previously. */
4582
4583 else
4584 hostlist = ob->hostlist;
4585 }
4586
4587 /* The host list was supplied with the address. If hosts_randomize is set, we
4588 must sort it into a random order if it did not come from MX records and has not
4589 already been randomized (but don't bother if continuing down an existing
4590 connection). */
4591
4592 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
4593 {
4594 host_item *newlist = NULL;
4595 while (hostlist)
4596 {
4597 host_item *h = hostlist;
4598 hostlist = hostlist->next;
4599
4600 h->sort_key = random_number(100);
4601
4602 if (!newlist)
4603 {
4604 h->next = NULL;
4605 newlist = h;
4606 }
4607 else if (h->sort_key < newlist->sort_key)
4608 {
4609 h->next = newlist;
4610 newlist = h;
4611 }
4612 else
4613 {
4614 host_item *hh = newlist;
4615 while (hh->next)
4616 {
4617 if (h->sort_key < hh->next->sort_key) break;
4618 hh = hh->next;
4619 }
4620 h->next = hh->next;
4621 hh->next = h;
4622 }
4623 }
4624
4625 hostlist = addrlist->host_list = newlist;
4626 }
4627
4628 /* Sort out the default port. */
4629
4630 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
4631
4632 /* For each host-plus-IP-address on the list:
4633
4634 . If this is a continued delivery and the host isn't the one with the
4635 current connection, skip.
4636
4637 . If the status is unusable (i.e. previously failed or retry checked), skip.
4638
4639 . If no IP address set, get the address, either by turning the name into
4640 an address, calling gethostbyname if gethostbyname is on, or by calling
4641 the DNS. The DNS may yield multiple addresses, in which case insert the
4642 extra ones into the list.
4643
4644 . Get the retry data if not previously obtained for this address and set the
4645 field which remembers the state of this address. Skip if the retry time is
4646 not reached. If not, remember whether retry data was found. The retry string
4647 contains both the name and the IP address.
4648
4649 . Scan the list of addresses and mark those whose status is DEFER as
4650 PENDING_DEFER. These are the only ones that will be processed in this cycle
4651 of the hosts loop.
4652
4653 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
4654 Some addresses may be successfully delivered, others may fail, and yet
4655 others may get temporary errors and so get marked DEFER.
4656
4657 . The return from the delivery attempt is OK if a connection was made and a
4658 valid SMTP dialogue was completed. Otherwise it is DEFER.
4659
4660 . If OK, add a "remove" retry item for this host/IPaddress, if any.
4661
4662 . If fail to connect, or other defer state, add a retry item.
4663
4664 . If there are any addresses whose status is still DEFER, carry on to the
4665 next host/IPaddress, unless we have tried the number of hosts given
4666 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
4667 there is some fancy logic for hosts_max_try that means its limit can be
4668 overstepped in some circumstances.
4669
4670 If we get to the end of the list, all hosts have deferred at least one address,
4671 or not reached their retry times. If delay_after_cutoff is unset, it requests a
4672 delivery attempt to those hosts whose last try was before the arrival time of
4673 the current message. To cope with this, we have to go round the loop a second
4674 time. After that, set the status and error data for any addresses that haven't
4675 had it set already. */
4676
4677 for (int cutoff_retry = 0;
4678 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
4679 cutoff_retry++)
4680 {
4681 host_item *nexthost = NULL;
4682 int unexpired_hosts_tried = 0;
4683 BOOL continue_host_tried = FALSE;
4684
4685 retry_non_continued:
4686 for (host = hostlist;
4687 host
4688 && unexpired_hosts_tried < ob->hosts_max_try
4689 && total_hosts_tried < ob->hosts_max_try_hardlimit;
4690 host = nexthost)
4691 {
4692 int rc;
4693 int host_af;
4694 BOOL host_is_expired = FALSE;
4695 BOOL message_defer = FALSE;
4696 BOOL some_deferred = FALSE;
4697 address_item *first_addr = NULL;
4698 uschar *interface = NULL;
4699 uschar *retry_host_key = NULL;
4700 uschar *retry_message_key = NULL;
4701 uschar *serialize_key = NULL;
4702
4703 /* Default next host is next host. :-) But this can vary if the
4704 hosts_max_try limit is hit (see below). It may also be reset if a host
4705 address is looked up here (in case the host was multihomed). */
4706
4707 nexthost = host->next;
4708
4709 /* If the address hasn't yet been obtained from the host name, look it up
4710 now, unless the host is already marked as unusable. If it is marked as
4711 unusable, it means that the router was unable to find its IP address (in
4712 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
4713 the lookup failed last time. We don't get this far if *all* MX records
4714 point to non-existent hosts; that is treated as a hard error.
4715
4716 We can just skip this host entirely. When the hosts came from the router,
4717 the address will timeout based on the other host(s); when the address is
4718 looked up below, there is an explicit retry record added.
4719
4720 Note that we mustn't skip unusable hosts if the address is not unset; they
4721 may be needed as expired hosts on the 2nd time round the cutoff loop. */
4722
4723 if (!host->address)
4724 {
4725 int new_port, flags;
4726
4727 if (host->status >= hstatus_unusable)
4728 {
4729 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
4730 host->name);
4731 continue;
4732 }
4733
4734 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
4735
4736 /* The host name is permitted to have an attached port. Find it, and
4737 strip it from the name. Just remember it for now. */
4738
4739 new_port = host_item_get_port(host);
4740
4741 /* Count hosts looked up */
4742
4743 hosts_looked_up++;
4744
4745 /* Find by name if so configured, or if it's an IP address. We don't
4746 just copy the IP address, because we need the test-for-local to happen. */
4747
4748 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
4749 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
4750 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
4751
4752 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
4753 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
4754 else
4755 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
4756 &ob->dnssec, /* domains for request/require */
4757 NULL, NULL);
4758
4759 /* Update the host (and any additional blocks, resulting from
4760 multihoming) with a host-specific port, if any. */
4761
4762 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
4763
4764 /* Failure to find the host at this time (usually DNS temporary failure)
4765 is really a kind of routing failure rather than a transport failure.
4766 Therefore we add a retry item of the routing kind, not to stop us trying
4767 to look this name up here again, but to ensure the address gets timed
4768 out if the failures go on long enough. A complete failure at this point
4769 commonly points to a configuration error, but the best action is still
4770 to carry on for the next host. */
4771
4772 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
4773 {
4774 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
4775 expired = FALSE;
4776 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
4777 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
4778 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
4779 host->status = hstatus_unusable;
4780
4781 for (address_item * addr = addrlist; addr; addr = addr->next)
4782 {
4783 if (addr->transport_return != DEFER) continue;
4784 addr->basic_errno = ERRNO_UNKNOWNHOST;
4785 addr->message = string_sprintf(
4786 rc == HOST_FIND_SECURITY
4787 ? "lookup of IP address for %s was insecure"
4788 : "failed to lookup IP address for %s",
4789 host->name);
4790 }
4791 continue;
4792 }
4793
4794 /* If the host is actually the local host, we may have a problem, or
4795 there may be some cunning configuration going on. In the problem case,
4796 log things and give up. The default transport status is already DEFER. */
4797
4798 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
4799 {
4800 for (address_item * addr = addrlist; addr; addr = addr->next)
4801 {
4802 addr->basic_errno = 0;
4803 addr->message = string_sprintf("%s transport found host %s to be "
4804 "local", tblock->name, host->name);
4805 }
4806 goto END_TRANSPORT;
4807 }
4808 } /* End of block for IP address lookup */
4809
4810 /* If this is a continued delivery, we are interested only in the host
4811 which matches the name of the existing open channel. The check is put
4812 here after the local host lookup, in case the name gets expanded as a
4813 result of the lookup. Set expired FALSE, to save the outer loop executing
4814 twice. */
4815
4816 if (continue_hostname)
4817 if ( Ustrcmp(continue_hostname, host->name) != 0
4818 || Ustrcmp(continue_host_address, host->address) != 0
4819 )
4820 {
4821 expired = FALSE;
4822 continue; /* With next host */
4823 }
4824 else
4825 continue_host_tried = TRUE;
4826
4827 /* Reset the default next host in case a multihomed host whose addresses
4828 are not looked up till just above added to the host list. */
4829
4830 nexthost = host->next;
4831
4832 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
4833 domain is in queue_smtp_domains, we don't actually want to attempt any
4834 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
4835 there is a lookup defer in queue_smtp_domains, proceed as if the domain
4836 were not in it. We don't want to hold up all SMTP deliveries! Except when
4837 doing a two-stage queue run, don't do this if forcing. */
4838
4839 if ((!f.deliver_force || f.queue_2stage) && (f.queue_smtp ||
4840 match_isinlist(addrlist->domain,
4841 (const uschar **)&queue_smtp_domains, 0,
4842 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
4843 {
4844 expired = FALSE;
4845 for (address_item * addr = addrlist; addr; addr = addr->next)
4846 if (addr->transport_return == DEFER)
4847 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
4848 continue; /* With next host */
4849 }
4850
4851 /* Count hosts being considered - purely for an intelligent comment
4852 if none are usable. */
4853
4854 hosts_total++;
4855
4856 /* Set $host and $host address now in case they are needed for the
4857 interface expansion or the serialize_hosts check; they remain set if an
4858 actual delivery happens. */
4859
4860 deliver_host = host->name;
4861 deliver_host_address = host->address;
4862 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
4863 : host->dnssec == DS_NO ? US"no"
4864 : US"";
4865
4866 /* Set up a string for adding to the retry key if the port number is not
4867 the standard SMTP port. A host may have its own port setting that overrides
4868 the default. */
4869
4870 pistring = string_sprintf(":%d", host->port == PORT_NONE
4871 ? defport : host->port);
4872 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
4873
4874 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
4875 string is set, even if constant (as different transports can have different
4876 constant settings), we must add it to the key that is used for retries,
4877 because connections to the same host from a different interface should be
4878 treated separately. */
4879
4880 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
4881 {
4882 uschar * s = ob->interface;
4883 if (s && *s)
4884 {
4885 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
4886 return FALSE;
4887 pistring = string_sprintf("%s/%s", pistring, interface);
4888 }
4889 }
4890
4891 /* The first time round the outer loop, check the status of the host by
4892 inspecting the retry data. The second time round, we are interested only
4893 in expired hosts that haven't been tried since this message arrived. */
4894
4895 if (cutoff_retry == 0)
4896 {
4897 BOOL incl_ip;
4898 /* Ensure the status of the address is set by checking retry data if
4899 necessary. There may be host-specific retry data (applicable to all
4900 messages) and also data for retries of a specific message at this host.
4901 If either of these retry records are actually read, the keys used are
4902 returned to save recomputing them later. */
4903
4904 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4905 US"retry_include_ip_address", ob->retry_include_ip_address,
4906 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4907 continue; /* with next host */
4908
4909 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4910 incl_ip, &retry_host_key, &retry_message_key);
4911
4912 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4913 host->address ? host->address : US"", pistring,
4914 host->status == hstatus_usable ? "usable"
4915 : host->status == hstatus_unusable ? "unusable"
4916 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
4917
4918 /* Skip this address if not usable at this time, noting if it wasn't
4919 actually expired, both locally and in the address. */
4920
4921 switch (host->status)
4922 {
4923 case hstatus_unusable:
4924 expired = FALSE;
4925 setflag(addrlist, af_retry_skipped);
4926 /* Fall through */
4927
4928 case hstatus_unusable_expired:
4929 switch (host->why)
4930 {
4931 case hwhy_retry: hosts_retry++; break;
4932 case hwhy_failed: hosts_fail++; break;
4933 case hwhy_insecure:
4934 case hwhy_deferred: hosts_defer++; break;
4935 }
4936
4937 /* If there was a retry message key, implying that previously there
4938 was a message-specific defer, we don't want to update the list of
4939 messages waiting for these hosts. */
4940
4941 if (retry_message_key) update_waiting = FALSE;
4942 continue; /* With the next host or IP address */
4943 }
4944 }
4945
4946 /* Second time round the loop: if the address is set but expired, and
4947 the message is newer than the last try, let it through. */
4948
4949 else
4950 {
4951 if ( !host->address
4952 || host->status != hstatus_unusable_expired
4953 || host->last_try > received_time.tv_sec)
4954 continue;
4955 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4956 host->name, host->address, pistring);
4957 host_is_expired = TRUE;
4958 }
4959
4960 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4961 it remains TRUE only if all hosts are expired and none are actually tried.
4962 */
4963
4964 expired = FALSE;
4965
4966 /* If this host is listed as one to which access must be serialized,
4967 see if another Exim process has a connection to it, and if so, skip
4968 this host. If not, update the database to record our connection to it
4969 and remember this for later deletion. Do not do any of this if we are
4970 sending the message down a pre-existing connection. */
4971
4972 if ( !continue_hostname
4973 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
4974 {
4975 serialize_key = string_sprintf("host-serialize-%s", host->name);
4976 if (!enq_start(serialize_key, 1))
4977 {
4978 DEBUG(D_transport)
4979 debug_printf("skipping host %s because another Exim process "
4980 "is connected to it\n", host->name);
4981 hosts_serial++;
4982 continue;
4983 }
4984 }
4985
4986 /* OK, we have an IP address that is not waiting for its retry time to
4987 arrive (it might be expired) OR (second time round the loop) we have an
4988 expired host that hasn't been tried since the message arrived. Have a go
4989 at delivering the message to it. First prepare the addresses by flushing
4990 out the result of previous attempts, and finding the first address that
4991 is still to be delivered. */
4992
4993 first_addr = prepare_addresses(addrlist, host);
4994
4995 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
4996 message_id, host->name, host->address, addrlist->address,
4997 addrlist->next ? ", ..." : "");
4998
4999 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5000 message_id, host->name, host->address, pistring, addrlist->address,
5001 addrlist->next ? ", ..." : "");
5002
5003 /* This is not for real; don't do the delivery. If there are
5004 any remaining hosts, list them. */
5005
5006 if (f.dont_deliver)
5007 {
5008 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
5009 for (address_item * addr = addrlist; addr; addr = addr->next)
5010 {
5011 addr->host_used = host;
5012 addr->special_action = '*';
5013 addr->message = US"delivery bypassed by -N option";
5014 }
5015 DEBUG(D_transport)
5016 {
5017 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5018 "*** host and remaining hosts:\n", tblock->name);
5019 for (host_item * host2 = host; host2; host2 = host2->next)
5020 debug_printf(" %s [%s]\n", host2->name,
5021 host2->address ? host2->address : US"unset");
5022 }
5023 rc = OK;
5024 }
5025
5026 /* This is for real. If the host is expired, we don't count it for
5027 hosts_max_retry. This ensures that all hosts must expire before an address
5028 is timed out, unless hosts_max_try_hardlimit (which protects against
5029 lunatic DNS configurations) is reached.
5030
5031 If the host is not expired and we are about to hit the hosts_max_retry
5032 limit, check to see if there is a subsequent hosts with a different MX
5033 value. If so, make that the next host, and don't count this one. This is a
5034 heuristic to make sure that different MXs do get tried. With a normal kind
5035 of retry rule, they would get tried anyway when the earlier hosts were
5036 delayed, but if the domain has a "retry every time" type of rule - as is
5037 often used for the the very large ISPs, that won't happen. */
5038
5039 else
5040 {
5041 host_item * thost;
5042 /* Make a copy of the host if it is local to this invocation
5043 of the transport. */
5044
5045 if (expanded_hosts)
5046 {
5047 thost = store_get(sizeof(host_item));
5048 *thost = *host;
5049 thost->name = string_copy(host->name);
5050 thost->address = string_copy(host->address);
5051 }
5052 else
5053 thost = host;
5054
5055 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5056 {
5057 DEBUG(D_transport)
5058 debug_printf("hosts_max_try limit reached with this host\n");
5059 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5060 {
5061 nexthost = h;
5062 unexpired_hosts_tried--;
5063 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5064 "and will be tried\n");
5065 break;
5066 }
5067 }
5068
5069 /* Attempt the delivery. */
5070
5071 total_hosts_tried++;
5072 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5073 &message_defer, FALSE);
5074
5075 /* Yield is one of:
5076 OK => connection made, each address contains its result;
5077 message_defer is set for message-specific defers (when all
5078 recipients are marked defer)
5079 DEFER => there was a non-message-specific delivery problem;
5080 ERROR => there was a problem setting up the arguments for a filter,
5081 or there was a problem with expanding added headers
5082 */
5083
5084 /* If the result is not OK, there was a non-message-specific problem.
5085 If the result is DEFER, we need to write to the logs saying what happened
5086 for this particular host, except in the case of authentication and TLS
5087 failures, where the log has already been written. If all hosts defer a
5088 general message is written at the end. */
5089
5090 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5091 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5092 write_logs(host, first_addr->message, first_addr->basic_errno);
5093
5094 #ifndef DISABLE_EVENT
5095 if (rc == DEFER)
5096 deferred_event_raise(first_addr, host);
5097 #endif
5098
5099 /* If STARTTLS was accepted, but there was a failure in setting up the
5100 TLS session (usually a certificate screwup), and the host is not in
5101 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5102 TLS forcibly turned off. We have to start from scratch with a new SMTP
5103 connection. That's why the retry is done from here, not from within
5104 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5105 session, so the in-clear transmission after those errors, if permitted,
5106 happens inside smtp_deliver().] */
5107
5108 #ifndef DISABLE_TLS
5109 if ( rc == DEFER
5110 && first_addr->basic_errno == ERRNO_TLSFAILURE
5111 && ob->tls_tempfail_tryclear
5112 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5113 )
5114 {
5115 log_write(0, LOG_MAIN,
5116 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5117 first_addr->message, host->name, host->address);
5118 first_addr = prepare_addresses(addrlist, host);
5119 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5120 &message_defer, TRUE);
5121 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5122 write_logs(host, first_addr->message, first_addr->basic_errno);
5123 # ifndef DISABLE_EVENT
5124 if (rc == DEFER)
5125 deferred_event_raise(first_addr, host);
5126 # endif
5127 }
5128 #endif /*DISABLE_TLS*/
5129 }
5130
5131 /* Delivery attempt finished */
5132
5133 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5134 message_id, host->name, host->address, pistring, addrlist->address,
5135 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5136
5137 /* Release serialization if set up */
5138
5139 if (serialize_key) enq_end(serialize_key);
5140
5141 /* If the result is DEFER, or if a host retry record is known to exist, we
5142 need to add an item to the retry chain for updating the retry database
5143 at the end of delivery. We only need to add the item to the top address,
5144 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5145 for any other delivery attempts using the same address. (It is copied into
5146 the unusable tree at the outer level, so even if different address blocks
5147 contain the same address, it still won't get tried again.) */
5148
5149 if (rc == DEFER || retry_host_key)
5150 {
5151 int delete_flag = rc != DEFER ? rf_delete : 0;
5152 if (!retry_host_key)
5153 {
5154 BOOL incl_ip;
5155 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5156 US"retry_include_ip_address", ob->retry_include_ip_address,
5157 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5158 incl_ip = TRUE; /* error; use most-specific retry record */
5159
5160 retry_host_key = incl_ip
5161 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5162 : string_sprintf("T:%S%s", host->name, pistring);
5163 }
5164
5165 /* If a delivery of another message over an existing SMTP connection
5166 yields DEFER, we do NOT set up retry data for the host. This covers the
5167 case when there are delays in routing the addresses in the second message
5168 that are so long that the server times out. This is alleviated by not
5169 routing addresses that previously had routing defers when handling an
5170 existing connection, but even so, this case may occur (e.g. if a
5171 previously happily routed address starts giving routing defers). If the
5172 host is genuinely down, another non-continued message delivery will
5173 notice it soon enough. */
5174
5175 if (delete_flag != 0 || !continue_hostname)
5176 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5177
5178 /* We may have tried an expired host, if its retry time has come; ensure
5179 the status reflects the expiry for the benefit of any other addresses. */
5180
5181 if (rc == DEFER)
5182 {
5183 host->status = host_is_expired
5184 ? hstatus_unusable_expired : hstatus_unusable;
5185 host->why = hwhy_deferred;
5186 }
5187 }
5188
5189 /* If message_defer is set (host was OK, but every recipient got deferred
5190 because of some message-specific problem), or if that had happened
5191 previously so that a message retry key exists, add an appropriate item
5192 to the retry chain. Note that if there was a message defer but now there is
5193 a host defer, the message defer record gets deleted. That seems perfectly
5194 reasonable. Also, stop the message from being remembered as waiting
5195 for specific hosts. */
5196
5197 if (message_defer || retry_message_key)
5198 {
5199 int delete_flag = message_defer ? 0 : rf_delete;
5200 if (!retry_message_key)
5201 {
5202 BOOL incl_ip;
5203 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5204 US"retry_include_ip_address", ob->retry_include_ip_address,
5205 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5206 incl_ip = TRUE; /* error; use most-specific retry record */
5207
5208 retry_message_key = incl_ip
5209 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5210 message_id)
5211 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5212 }
5213 retry_add_item(addrlist, retry_message_key,
5214 rf_message | rf_host | delete_flag);
5215 update_waiting = FALSE;
5216 }
5217
5218 /* Any return other than DEFER (that is, OK or ERROR) means that the
5219 addresses have got their final statuses filled in for this host. In the OK
5220 case, see if any of them are deferred. */
5221
5222 if (rc == OK)
5223 for (address_item * addr = addrlist; addr; addr = addr->next)
5224 if (addr->transport_return == DEFER)
5225 {
5226 some_deferred = TRUE;
5227 break;
5228 }
5229
5230 /* If no addresses deferred or the result was ERROR, return. We do this for
5231 ERROR because a failing filter set-up or add_headers expansion is likely to
5232 fail for any host we try. */
5233
5234 if (rc == ERROR || (rc == OK && !some_deferred))
5235 {
5236 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5237 return TRUE; /* Each address has its status */
5238 }
5239
5240 /* If the result was DEFER or some individual addresses deferred, let
5241 the loop run to try other hosts with the deferred addresses, except for the
5242 case when we were trying to deliver down an existing channel and failed.
5243 Don't try any other hosts in this case. */
5244
5245 if (continue_hostname) break;
5246
5247 /* If the whole delivery, or some individual addresses, were deferred and
5248 there are more hosts that could be tried, do not count this host towards
5249 the hosts_max_try limit if the age of the message is greater than the
5250 maximum retry time for this host. This means we may try try all hosts,
5251 ignoring the limit, when messages have been around for some time. This is
5252 important because if we don't try all hosts, the address will never time
5253 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5254
5255 if ((rc == DEFER || some_deferred) && nexthost)
5256 {
5257 BOOL timedout;
5258 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5259
5260 if (retry && retry->rules)
5261 {
5262 retry_rule *last_rule;
5263 for (last_rule = retry->rules;
5264 last_rule->next;
5265 last_rule = last_rule->next);
5266 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5267 }
5268 else timedout = TRUE; /* No rule => timed out */
5269
5270 if (timedout)
5271 {
5272 unexpired_hosts_tried--;
5273 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5274 "hosts_max_try (message older than host's retry time)\n");
5275 }
5276 }
5277
5278 DEBUG(D_transport)
5279 {
5280 if (unexpired_hosts_tried >= ob->hosts_max_try)
5281 debug_printf("reached transport hosts_max_try limit %d\n",
5282 ob->hosts_max_try);
5283 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5284 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5285 ob->hosts_max_try_hardlimit);
5286 }
5287
5288 if (f.running_in_test_harness) millisleep(500); /* let server debug out */
5289 } /* End of loop for trying multiple hosts. */
5290
5291 /* If we failed to find a matching host in the list, for an already-open
5292 connection, just close it and start over with the list. This can happen
5293 for routing that changes from run to run, or big multi-IP sites with
5294 round-robin DNS. */
5295
5296 if (continue_hostname && !continue_host_tried)
5297 {
5298 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5299
5300 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5301 #ifndef DISABLE_TLS
5302 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5303 transport */
5304 /*XXX doublecheck that! */
5305
5306 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5307 {
5308 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5309 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5310 cutthrough.cctx.tls_ctx = NULL;
5311 cutthrough.is_tls = FALSE;
5312 }
5313 else
5314 #else
5315 (void) write(fd, US"QUIT\r\n", 6);
5316 #endif
5317 (void) close(fd);
5318 cutthrough.cctx.sock = -1;
5319 continue_hostname = NULL;
5320 goto retry_non_continued;
5321 }
5322
5323 /* This is the end of the loop that repeats iff expired is TRUE and
5324 ob->delay_after_cutoff is FALSE. The second time round we will
5325 try those hosts that haven't been tried since the message arrived. */
5326
5327 DEBUG(D_transport)
5328 {
5329 debug_printf("all IP addresses skipped or deferred at least one address\n");
5330 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5331 debug_printf("retrying IP addresses not tried since message arrived\n");
5332 }
5333 }
5334
5335
5336 /* Get here if all IP addresses are skipped or defer at least one address. In
5337 MUA wrapper mode, this will happen only for connection or other non-message-
5338 specific failures. Force the delivery status for all addresses to FAIL. */
5339
5340 if (mua_wrapper)
5341 {
5342 for (address_item * addr = addrlist; addr; addr = addr->next)
5343 addr->transport_return = FAIL;
5344 goto END_TRANSPORT;
5345 }
5346
5347 /* In the normal, non-wrapper case, add a standard message to each deferred
5348 address if there hasn't been an error, that is, if it hasn't actually been
5349 tried this time. The variable "expired" will be FALSE if any deliveries were
5350 actually tried, or if there was at least one host that was not expired. That
5351 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
5352 a delivery has been tried, an error code will be set, and the failing of the
5353 message is handled by the retry code later.
5354
5355 If queue_smtp is set, or this transport was called to send a subsequent message
5356 down an existing TCP/IP connection, and something caused the host not to be
5357 found, we end up here, but can detect these cases and handle them specially. */
5358
5359 for (address_item * addr = addrlist; addr; addr = addr->next)
5360 {
5361 /* If host is not NULL, it means that we stopped processing the host list
5362 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
5363 means we need to behave as if some hosts were skipped because their retry
5364 time had not come. Specifically, this prevents the address from timing out.
5365 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
5366 hosts were tried. */
5367
5368 if (host)
5369 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5370 {
5371 DEBUG(D_transport)
5372 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
5373 "hosts were tried\n");
5374 }
5375 else
5376 {
5377 DEBUG(D_transport)
5378 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
5379 setflag(addr, af_retry_skipped);
5380 }
5381
5382 if (f.queue_smtp) /* no deliveries attempted */
5383 {
5384 addr->transport_return = DEFER;
5385 addr->basic_errno = 0;
5386 addr->message = US"SMTP delivery explicitly queued";
5387 }
5388
5389 else if ( addr->transport_return == DEFER
5390 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
5391 && !addr->message
5392 )
5393 {
5394 addr->basic_errno = ERRNO_HRETRY;
5395 if (continue_hostname)
5396 addr->message = US"no host found for existing SMTP connection";
5397 else if (expired)
5398 {
5399 setflag(addr, af_pass_message); /* This is not a security risk */
5400 addr->message = string_sprintf(
5401 "all hosts%s have been failing for a long time %s",
5402 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
5403 ob->delay_after_cutoff
5404 ? US"(and retry time not reached)"
5405 : US"and were last tried after this message arrived");
5406
5407 /* If we are already using fallback hosts, or there are no fallback hosts
5408 defined, convert the result to FAIL to cause a bounce. */
5409
5410 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
5411 addr->transport_return = FAIL;
5412 }
5413 else
5414 {
5415 const char * s;
5416 if (hosts_retry == hosts_total)
5417 s = "retry time not reached for any host%s";
5418 else if (hosts_fail == hosts_total)
5419 s = "all host address lookups%s failed permanently";
5420 else if (hosts_defer == hosts_total)
5421 s = "all host address lookups%s failed temporarily";
5422 else if (hosts_serial == hosts_total)
5423 s = "connection limit reached for all hosts%s";
5424 else if (hosts_fail+hosts_defer == hosts_total)
5425 s = "all host address lookups%s failed";
5426 else
5427 s = "some host address lookups failed and retry time "
5428 "not reached for other hosts or connection limit reached%s";
5429
5430 addr->message = string_sprintf(s,
5431 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
5432 }
5433 }
5434 }
5435
5436 /* Update the database which keeps information about which messages are waiting
5437 for which hosts to become available. For some message-specific errors, the
5438 update_waiting flag is turned off because we don't want follow-on deliveries in
5439 those cases. If this transport instance is explicitly limited to one message
5440 per connection then follow-on deliveries are not possible and there's no need
5441 to create/update the per-transport wait-<transport_name> database. */
5442
5443 if (update_waiting && tblock->connection_max_messages != 1)
5444 transport_update_waiting(hostlist, tblock->name);
5445
5446 END_TRANSPORT:
5447
5448 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5449
5450 return TRUE; /* Each address has its status */
5451 }
5452
5453 #endif /*!MACRO_PREDEF*/
5454 /* vi: aw ai sw=2
5455 */
5456 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.