1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* Copyright (c) The Exim Maintainers 2020 */
7 /* See the file NOTICE for conditions of use and distribution. */
8
9 #include "../exim.h"
10 #include "smtp.h"
11
12 #if defined(SUPPORT_DANE) && defined(DISABLE_TLS)
13 # error TLS is required for DANE
14 #endif
15
16
17 /* Options specific to the smtp transport. This transport also supports LMTP
18 over TCP/IP. The options must be in alphabetic order (note that "_" comes
19 before the lower case letters). Some live in the transport_instance block so as
20 to be publicly visible; these are flagged with opt_public. */
21
22 #define LOFF(field) OPT_OFF(smtp_transport_options_block, field)
23
24 optionlist smtp_transport_options[] = {
25 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
26 OPT_OFF(transport_instance, expand_multi_domain) },
27 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
28 LOFF(expand_retry_include_ip_address) },
29
30 { "address_retry_include_sender", opt_bool,
31 LOFF(address_retry_include_sender) },
32 { "allow_localhost", opt_bool, LOFF(allow_localhost) },
33 #ifdef EXPERIMENTAL_ARC
34 { "arc_sign", opt_stringptr, LOFF(arc_sign) },
35 #endif
36 { "authenticated_sender", opt_stringptr, LOFF(authenticated_sender) },
37 { "authenticated_sender_force", opt_bool, LOFF(authenticated_sender_force) },
38 { "command_timeout", opt_time, LOFF(command_timeout) },
39 { "connect_timeout", opt_time, LOFF(connect_timeout) },
40 { "connection_max_messages", opt_int | opt_public,
41 OPT_OFF(transport_instance, connection_max_messages) },
42 # ifdef SUPPORT_DANE
43 { "dane_require_tls_ciphers", opt_stringptr, LOFF(dane_require_tls_ciphers) },
44 # endif
45 { "data_timeout", opt_time, LOFF(data_timeout) },
46 { "delay_after_cutoff", opt_bool, LOFF(delay_after_cutoff) },
47 #ifndef DISABLE_DKIM
48 { "dkim_canon", opt_stringptr, LOFF(dkim.dkim_canon) },
49 { "dkim_domain", opt_stringptr, LOFF(dkim.dkim_domain) },
50 { "dkim_hash", opt_stringptr, LOFF(dkim.dkim_hash) },
51 { "dkim_identity", opt_stringptr, LOFF(dkim.dkim_identity) },
52 { "dkim_private_key", opt_stringptr, LOFF(dkim.dkim_private_key) },
53 { "dkim_selector", opt_stringptr, LOFF(dkim.dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr, LOFF(dkim.dkim_sign_headers) },
55 { "dkim_strict", opt_stringptr, LOFF(dkim.dkim_strict) },
56 { "dkim_timestamps", opt_stringptr, LOFF(dkim.dkim_timestamps) },
57 #endif
58 { "dns_qualify_single", opt_bool, LOFF(dns_qualify_single) },
59 { "dns_search_parents", opt_bool, LOFF(dns_search_parents) },
60 { "dnssec_request_domains", opt_stringptr, LOFF(dnssec.request) },
61 { "dnssec_require_domains", opt_stringptr, LOFF(dnssec.require) },
62 { "dscp", opt_stringptr, LOFF(dscp) },
63 { "fallback_hosts", opt_stringptr, LOFF(fallback_hosts) },
64 { "final_timeout", opt_time, LOFF(final_timeout) },
65 { "gethostbyname", opt_bool, LOFF(gethostbyname) },
66 { "helo_data", opt_stringptr, LOFF(helo_data) },
67 { "hosts", opt_stringptr, LOFF(hosts) },
68 { "hosts_avoid_esmtp", opt_stringptr, LOFF(hosts_avoid_esmtp) },
69 { "hosts_avoid_pipelining", opt_stringptr, LOFF(hosts_avoid_pipelining) },
70 #ifndef DISABLE_TLS
71 { "hosts_avoid_tls", opt_stringptr, LOFF(hosts_avoid_tls) },
72 #endif
73 { "hosts_max_try", opt_int, LOFF(hosts_max_try) },
74 { "hosts_max_try_hardlimit", opt_int, LOFF(hosts_max_try_hardlimit) },
75 #ifndef DISABLE_TLS
76 { "hosts_nopass_tls", opt_stringptr, LOFF(hosts_nopass_tls) },
77 { "hosts_noproxy_tls", opt_stringptr, LOFF(hosts_noproxy_tls) },
78 #endif
79 { "hosts_override", opt_bool, LOFF(hosts_override) },
80 #ifndef DISABLE_PIPE_CONNECT
81 { "hosts_pipe_connect", opt_stringptr, LOFF(hosts_pipe_connect) },
82 #endif
83 { "hosts_randomize", opt_bool, LOFF(hosts_randomize) },
84 #if !defined(DISABLE_TLS) && !defined(DISABLE_OCSP)
85 { "hosts_request_ocsp", opt_stringptr, LOFF(hosts_request_ocsp) },
86 #endif
87 { "hosts_require_alpn", opt_stringptr, LOFF(hosts_require_alpn) },
88 { "hosts_require_auth", opt_stringptr, LOFF(hosts_require_auth) },
89 #ifndef DISABLE_TLS
90 # ifdef SUPPORT_DANE
91 { "hosts_require_dane", opt_stringptr, LOFF(hosts_require_dane) },
92 # endif
93 # ifndef DISABLE_OCSP
94 { "hosts_require_ocsp", opt_stringptr, LOFF(hosts_require_ocsp) },
95 # endif
96 { "hosts_require_tls", opt_stringptr, LOFF(hosts_require_tls) },
97 #endif
98 { "hosts_try_auth", opt_stringptr, LOFF(hosts_try_auth) },
99 { "hosts_try_chunking", opt_stringptr, LOFF(hosts_try_chunking) },
100 #ifdef SUPPORT_DANE
101 { "hosts_try_dane", opt_stringptr, LOFF(hosts_try_dane) },
102 #endif
103 { "hosts_try_fastopen", opt_stringptr, LOFF(hosts_try_fastopen) },
104 #ifndef DISABLE_PRDR
105 { "hosts_try_prdr", opt_stringptr, LOFF(hosts_try_prdr) },
106 #endif
107 #ifndef DISABLE_TLS
108 { "hosts_verify_avoid_tls", opt_stringptr, LOFF(hosts_verify_avoid_tls) },
109 #endif
110 { "interface", opt_stringptr, LOFF(interface) },
111 { "keepalive", opt_bool, LOFF(keepalive) },
112 { "lmtp_ignore_quota", opt_bool, LOFF(lmtp_ignore_quota) },
113 { "max_rcpt", opt_int | opt_public,
114 OPT_OFF(transport_instance, max_addresses) },
115 { "message_linelength_limit", opt_int, LOFF(message_linelength_limit) },
116 { "multi_domain", opt_expand_bool | opt_public,
117 OPT_OFF(transport_instance, multi_domain) },
118 { "port", opt_stringptr, LOFF(port) },
119 { "protocol", opt_stringptr, LOFF(protocol) },
120 { "retry_include_ip_address", opt_expand_bool, LOFF(retry_include_ip_address) },
121 { "serialize_hosts", opt_stringptr, LOFF(serialize_hosts) },
122 { "size_addition", opt_int, LOFF(size_addition) },
123 #ifdef SUPPORT_SOCKS
124 { "socks_proxy", opt_stringptr, LOFF(socks_proxy) },
125 #endif
126 #ifndef DISABLE_TLS
127 { "tls_alpn", opt_stringptr, LOFF(tls_alpn) },
128 { "tls_certificate", opt_stringptr, LOFF(tls_certificate) },
129 { "tls_crl", opt_stringptr, LOFF(tls_crl) },
130 { "tls_dh_min_bits", opt_int, LOFF(tls_dh_min_bits) },
131 { "tls_privatekey", opt_stringptr, LOFF(tls_privatekey) },
132 { "tls_require_ciphers", opt_stringptr, LOFF(tls_require_ciphers) },
133 # ifndef DISABLE_TLS_RESUME
134 { "tls_resumption_hosts", opt_stringptr, LOFF(tls_resumption_hosts) },
135 # endif
136 { "tls_sni", opt_stringptr, LOFF(tls_sni) },
137 { "tls_tempfail_tryclear", opt_bool, LOFF(tls_tempfail_tryclear) },
138 { "tls_try_verify_hosts", opt_stringptr, LOFF(tls_try_verify_hosts) },
139 { "tls_verify_cert_hostnames", opt_stringptr, LOFF(tls_verify_cert_hostnames)},
140 { "tls_verify_certificates", opt_stringptr, LOFF(tls_verify_certificates) },
141 { "tls_verify_hosts", opt_stringptr, LOFF(tls_verify_hosts) },
142 #endif
143 #ifdef SUPPORT_I18N
144 { "utf8_downconvert", opt_stringptr, LOFF(utf8_downconvert) },
145 #endif
146 };
147
148 /* Size of the options list. An extern variable has to be used so that its
149 address can appear in the tables drtables.c. */
150
151 int smtp_transport_options_count = nelem(smtp_transport_options);
152
153
154 #ifdef MACRO_PREDEF
155
156 /* Dummy values */
157 smtp_transport_options_block smtp_transport_option_defaults = {0};
smtp_transport_init(transport_instance * tblock)158 void smtp_transport_init(transport_instance *tblock) {}
smtp_transport_entry(transport_instance * tblock,address_item * addr)159 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
smtp_transport_closedown(transport_instance * tblock)160 void smtp_transport_closedown(transport_instance *tblock) {}
161
162 #else /*!MACRO_PREDEF*/
163
164
165 /* Default private options block for the smtp transport. */
166
167 smtp_transport_options_block smtp_transport_option_defaults = {
168 /* All non-mentioned elements 0/NULL/FALSE */
169 .helo_data = US"$primary_hostname",
170 .protocol = US"smtp",
171 .hosts_try_chunking = US"*",
172 #ifdef SUPPORT_DANE
173 .hosts_try_dane = US"*",
174 #endif
175 .hosts_try_fastopen = US"*",
176 #ifndef DISABLE_PRDR
177 .hosts_try_prdr = US"*",
178 #endif
179 #ifndef DISABLE_OCSP
180 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
181 #endif
182 .command_timeout = 5*60,
183 .connect_timeout = 5*60,
184 .data_timeout = 5*60,
185 .final_timeout = 10*60,
186 .size_addition = 1024,
187 .hosts_max_try = 5,
188 .hosts_max_try_hardlimit = 50,
189 .message_linelength_limit = 998,
190 .address_retry_include_sender = TRUE,
191 .dns_qualify_single = TRUE,
192 .dnssec = { .request= US"*", .require=NULL },
193 .delay_after_cutoff = TRUE,
194 .keepalive = TRUE,
195 .retry_include_ip_address = TRUE,
196 #ifndef DISABLE_TLS
197 .tls_verify_certificates = US"system",
198 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
199 .tls_tempfail_tryclear = TRUE,
200 .tls_try_verify_hosts = US"*",
201 .tls_verify_cert_hostnames = US"*",
202 #endif
203 #ifdef SUPPORT_I18N
204 .utf8_downconvert = US"-1",
205 #endif
206 #ifndef DISABLE_DKIM
207 .dkim =
208 { .dkim_hash = US"sha256", },
209 #endif
210 };
211
212 /* some DSN flags for use later */
213
214 static int rf_list[] = {rf_notify_never, rf_notify_success,
215 rf_notify_failure, rf_notify_delay };
216
217 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
218
219
220
221 /* Local statics */
222
223 static uschar *smtp_command; /* Points to last cmd for error messages */
224 static uschar *mail_command; /* Points to MAIL cmd for error messages */
225 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
226 static BOOL update_waiting; /* TRUE to update the "wait" database */
227
228 /*XXX move to smtp_context */
229 static BOOL pipelining_active; /* current transaction is in pipe mode */
230
231
232 static unsigned ehlo_response(uschar * buf, unsigned checks);
233
234
235 /******************************************************************************/
236
237 void
smtp_deliver_init(void)238 smtp_deliver_init(void)
239 {
240 if (!regex_PIPELINING) regex_PIPELINING =
241 regex_must_compile(US"\\n250[\\s\\-]PIPELINING(\\s|\\n|$)", FALSE, TRUE);
242
243 if (!regex_SIZE) regex_SIZE =
244 regex_must_compile(US"\\n250[\\s\\-]SIZE(\\s|\\n|$)", FALSE, TRUE);
245
246 if (!regex_AUTH) regex_AUTH =
247 regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
248
249 #ifndef DISABLE_TLS
250 if (!regex_STARTTLS) regex_STARTTLS =
251 regex_must_compile(US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE, TRUE);
252 #endif
253
254 if (!regex_CHUNKING) regex_CHUNKING =
255 regex_must_compile(US"\\n250[\\s\\-]CHUNKING(\\s|\\n|$)", FALSE, TRUE);
256
257 #ifndef DISABLE_PRDR
258 if (!regex_PRDR) regex_PRDR =
259 regex_must_compile(US"\\n250[\\s\\-]PRDR(\\s|\\n|$)", FALSE, TRUE);
260 #endif
261
262 #ifdef SUPPORT_I18N
263 if (!regex_UTF8) regex_UTF8 =
264 regex_must_compile(US"\\n250[\\s\\-]SMTPUTF8(\\s|\\n|$)", FALSE, TRUE);
265 #endif
266
267 if (!regex_DSN) regex_DSN =
268 regex_must_compile(US"\\n250[\\s\\-]DSN(\\s|\\n|$)", FALSE, TRUE);
269
270 if (!regex_IGNOREQUOTA) regex_IGNOREQUOTA =
271 regex_must_compile(US"\\n250[\\s\\-]IGNOREQUOTA(\\s|\\n|$)", FALSE, TRUE);
272
273 #ifndef DISABLE_PIPE_CONNECT
274 if (!regex_EARLY_PIPE) regex_EARLY_PIPE =
275 regex_must_compile(US"\\n250[\\s\\-]" EARLY_PIPE_FEATURE_NAME "(\\s|\\n|$)", FALSE, TRUE);
276 #endif
277
278 #ifdef EXPERIMENTAL_ESMTP_LIMITS
279 if (!regex_LIMITS) regex_LIMITS =
280 regex_must_compile(US"\\n250[\\s\\-]LIMITS\\s", FALSE, TRUE);
281 #endif
282 }
283
284
285 /*************************************************
286 * Setup entry point *
287 *************************************************/
288
289 /* This function is called when the transport is about to be used,
290 but before running it in a sub-process. It is used for two things:
291
292 (1) To set the fallback host list in addresses, when delivering.
293 (2) To pass back the interface, port, protocol, and other options, for use
294 during callout verification.
295
296 Arguments:
297 tblock pointer to the transport instance block
298 addrlist list of addresses about to be transported
299 tf if not NULL, pointer to block in which to return options
300 uid the uid that will be set (not used)
301 gid the gid that will be set (not used)
302 errmsg place for error message (not used)
303
304 Returns: OK always (FAIL, DEFER not used)
305 */
306
307 static int
smtp_transport_setup(transport_instance * tblock,address_item * addrlist,transport_feedback * tf,uid_t uid,gid_t gid,uschar ** errmsg)308 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
309 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
310 {
311 smtp_transport_options_block *ob = SOB tblock->options_block;
312
313 /* Pass back options if required. This interface is getting very messy. */
314
315 if (tf)
316 {
317 tf->interface = ob->interface;
318 tf->port = ob->port;
319 tf->protocol = ob->protocol;
320 tf->hosts = ob->hosts;
321 tf->hosts_override = ob->hosts_override;
322 tf->hosts_randomize = ob->hosts_randomize;
323 tf->gethostbyname = ob->gethostbyname;
324 tf->qualify_single = ob->dns_qualify_single;
325 tf->search_parents = ob->dns_search_parents;
326 tf->helo_data = ob->helo_data;
327 }
328
329 /* Set the fallback host list for all the addresses that don't have fallback
330 host lists, provided that the local host wasn't present in the original host
331 list. */
332
333 if (!testflag(addrlist, af_local_host_removed))
334 for (; addrlist; addrlist = addrlist->next)
335 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
336
337 return OK;
338 }
339
340
341
342 /*************************************************
343 * Initialization entry point *
344 *************************************************/
345
346 /* Called for each instance, after its options have been read, to
347 enable consistency checks to be done, or anything else that needs
348 to be set up.
349
350 Argument: pointer to the transport instance block
351 Returns: nothing
352 */
353
354 void
smtp_transport_init(transport_instance * tblock)355 smtp_transport_init(transport_instance *tblock)
356 {
357 smtp_transport_options_block *ob = SOB tblock->options_block;
358 int old_pool = store_pool;
359
360 /* Retry_use_local_part defaults FALSE if unset */
361
362 if (tblock->retry_use_local_part == TRUE_UNSET)
363 tblock->retry_use_local_part = FALSE;
364
365 /* Set the default port according to the protocol */
366
367 if (!ob->port)
368 ob->port = strcmpic(ob->protocol, US"lmtp") == 0
369 ? US"lmtp"
370 : strcmpic(ob->protocol, US"smtps") == 0
371 ? US"smtps" : US"smtp";
372
373 /* Set up the setup entry point, to be called before subprocesses for this
374 transport. */
375
376 tblock->setup = smtp_transport_setup;
377
378 /* Complain if any of the timeouts are zero. */
379
380 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
381 ob->final_timeout <= 0)
382 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
383 "command, data, or final timeout value is zero for %s transport",
384 tblock->name);
385
386 /* If hosts_override is set and there are local hosts, set the global
387 flag that stops verify from showing router hosts. */
388
389 if (ob->hosts_override && ob->hosts) tblock->overrides_hosts = TRUE;
390
391 /* If there are any fallback hosts listed, build a chain of host items
392 for them, but do not do any lookups at this time. */
393
394 store_pool = POOL_PERM;
395 host_build_hostlist(&ob->fallback_hostlist, ob->fallback_hosts, FALSE);
396 store_pool = old_pool;
397 }
398
399
400
401
402
403 /*************************************************
404 * Set delivery info into all active addresses *
405 *************************************************/
406
407 /* Only addresses whose status is >= PENDING are relevant. A lesser
408 status means that an address is not currently being processed.
409
410 Arguments:
411 addrlist points to a chain of addresses
412 errno_value to put in each address's errno field
413 msg to put in each address's message field
414 rc to put in each address's transport_return field
415 pass_message if TRUE, set the "pass message" flag in the address
416 host if set, mark addrs as having used this host
417 smtp_greeting from peer
418 helo_response from peer
419 start points to timestamp of delivery start
420
421 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
422 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
423 this particular type of timeout.
424
425 Returns: nothing
426 */
427
428 static void
set_errno(address_item * addrlist,int errno_value,uschar * msg,int rc,BOOL pass_message,host_item * host,const uschar * smtp_greeting,const uschar * helo_response,struct timeval * start)429 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
430 BOOL pass_message, host_item * host,
431 #ifdef EXPERIMENTAL_DSN_INFO
432 const uschar * smtp_greeting, const uschar * helo_response,
433 #endif
434 struct timeval * start
435 )
436 {
437 int orvalue = 0;
438 struct timeval deliver_time;
439
440 if (errno_value == ERRNO_CONNECTTIMEOUT)
441 {
442 errno_value = ETIMEDOUT;
443 orvalue = RTEF_CTOUT;
444 }
445 timesince(&deliver_time, start);
446
447 for (address_item * addr = addrlist; addr; addr = addr->next)
448 if (addr->transport_return >= PENDING)
449 {
450 addr->basic_errno = errno_value;
451 addr->more_errno |= orvalue;
452 addr->delivery_time = deliver_time;
453 if (msg)
454 {
455 addr->message = msg;
456 if (pass_message) setflag(addr, af_pass_message);
457 }
458 addr->transport_return = rc;
459 if (host)
460 {
461 addr->host_used = host;
462 #ifdef EXPERIMENTAL_DSN_INFO
463 if (smtp_greeting)
464 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
465 addr->smtp_greeting = smtp_greeting;
466
467 if (helo_response)
468 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
469 addr->helo_response = helo_response;
470 #endif
471 }
472 }
473 }
474
475 static void
set_errno_nohost(address_item * addrlist,int errno_value,uschar * msg,int rc,BOOL pass_message,struct timeval * start)476 set_errno_nohost(address_item * addrlist, int errno_value, uschar * msg, int rc,
477 BOOL pass_message, struct timeval * start)
478 {
479 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL,
480 #ifdef EXPERIMENTAL_DSN_INFO
481 NULL, NULL,
482 #endif
483 start);
484 }
485
486
487 /*************************************************
488 * Check an SMTP response *
489 *************************************************/
490
491 /* This function is given an errno code and the SMTP response buffer
492 to analyse, together with the host identification for generating messages. It
493 sets an appropriate message and puts the first digit of the response code into
494 the yield variable. If no response was actually read, a suitable digit is
495 chosen.
496
497 Arguments:
498 host the current host, to get its name for messages
499 errno_value pointer to the errno value
500 more_errno from the top address for use with ERRNO_FILTER_FAIL
501 buffer the SMTP response buffer
502 yield where to put a one-digit SMTP response code
503 message where to put an error message
504 pass_message set TRUE if message is an SMTP response
505
506 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
507 */
508
509 static BOOL
check_response(host_item * host,int * errno_value,int more_errno,uschar * buffer,int * yield,uschar ** message,BOOL * pass_message)510 check_response(host_item *host, int *errno_value, int more_errno,
511 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
512 {
513 uschar * pl = pipelining_active ? US"pipelined " : US"";
514 const uschar * s;
515
516 *yield = '4'; /* Default setting is to give a temporary error */
517
518 switch(*errno_value)
519 {
520 case ETIMEDOUT: /* Handle response timeout */
521 *message = US string_sprintf("SMTP timeout after %s%s",
522 pl, smtp_command);
523 if (transport_count > 0)
524 *message = US string_sprintf("%s (%d bytes written)", *message,
525 transport_count);
526 return FALSE;
527
528 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
529 s = string_printing(buffer);
530 while (isspace(*s)) s++;
531 *message = *s == 0
532 ? string_sprintf("Malformed SMTP reply (an empty line) "
533 "in response to %s%s", pl, smtp_command)
534 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
535 pl, smtp_command, s);
536 return FALSE;
537
538 case ERRNO_TLSFAILURE: /* Handle bad first read; can happen with
539 GnuTLS and TLS1.3 */
540 *message = US"bad first read from TLS conn";
541 return TRUE;
542
543 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
544 can't send QUIT as we mustn't end the DATA. */
545 *message = string_sprintf("transport filter process failed (%d)%s",
546 more_errno,
547 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
548 return FALSE;
549
550 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
551 can't send QUIT as we mustn't end the DATA. */
552 *message =
553 string_sprintf("failed to expand headers_add or headers_remove: %s",
554 expand_string_message);
555 return FALSE;
556
557 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
558 *message = US"failed to write a data block";
559 return FALSE;
560
561 #ifdef SUPPORT_I18N
562 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
563 *message = US"utf8 support required but not offered for forwarding";
564 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
565 return TRUE;
566 #endif
567 }
568
569 /* Handle error responses from the remote mailer. */
570
571 if (buffer[0] != 0)
572 {
573 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
574 "%s", pl, smtp_command, s = string_printing(buffer));
575 *pass_message = TRUE;
576 *yield = buffer[0];
577 return TRUE;
578 }
579
580 /* No data was read. If there is no errno, this must be the EOF (i.e.
581 connection closed) case, which causes deferral. An explicit connection reset
582 error has the same effect. Otherwise, put the host's identity in the message,
583 leaving the errno value to be interpreted as well. In all cases, we have to
584 assume the connection is now dead. */
585
586 if (*errno_value == 0 || *errno_value == ECONNRESET)
587 {
588 *errno_value = ERRNO_SMTPCLOSED;
589 *message = US string_sprintf("Remote host closed connection "
590 "in response to %s%s", pl, smtp_command);
591 }
592 else
593 *message = US string_sprintf("%s [%s]", host->name, host->address);
594
595 return FALSE;
596 }
597
598
599
600 /*************************************************
601 * Write error message to logs *
602 *************************************************/
603
604 /* This writes to the main log and to the message log.
605
606 Arguments:
607 host the current host
608 detail the current message (addr_item->message)
609 basic_errno the errno (addr_item->basic_errno)
610
611 Returns: nothing
612 */
613
614 static void
write_logs(const host_item * host,const uschar * suffix,int basic_errno)615 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
616 {
617 gstring * message = LOGGING(outgoing_port)
618 ? string_fmt_append(NULL, "H=%s [%s]:%d", host->name, host->address,
619 host->port == PORT_NONE ? 25 : host->port)
620 : string_fmt_append(NULL, "H=%s [%s]", host->name, host->address);
621
622 if (suffix)
623 {
624 message = string_fmt_append(message, ": %s", suffix);
625 if (basic_errno > 0)
626 message = string_fmt_append(message, ": %s", strerror(basic_errno));
627 }
628 else
629 message = string_fmt_append(message, " %s", exim_errstr(basic_errno));
630
631 log_write(0, LOG_MAIN, "%s", string_from_gstring(message));
632 deliver_msglog("%s %s\n", tod_stamp(tod_log), message->s);
633 }
634
635 static void
msglog_line(host_item * host,uschar * message)636 msglog_line(host_item * host, uschar * message)
637 {
638 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
639 host->name, host->address, message);
640 }
641
642
643
644 #ifndef DISABLE_EVENT
645 /*************************************************
646 * Post-defer action *
647 *************************************************/
648
649 /* This expands an arbitrary per-transport string.
650 It might, for example, be used to write to the database log.
651
652 Arguments:
653 addr the address item containing error information
654 host the current host
655 evstr the event
656
657 Returns: nothing
658 */
659
660 static void
deferred_event_raise(address_item * addr,host_item * host,uschar * evstr)661 deferred_event_raise(address_item * addr, host_item * host, uschar * evstr)
662 {
663 uschar * action = addr->transport->event_action;
664 const uschar * save_domain;
665 uschar * save_local;
666
667 if (!action)
668 return;
669
670 save_domain = deliver_domain;
671 save_local = deliver_localpart;
672
673 /*XXX would ip & port already be set up? */
674 deliver_host_address = string_copy(host->address);
675 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
676 event_defer_errno = addr->basic_errno;
677
678 router_name = addr->router->name;
679 transport_name = addr->transport->name;
680 deliver_domain = addr->domain;
681 deliver_localpart = addr->local_part;
682
683 (void) event_raise(action, evstr,
684 addr->message
685 ? addr->basic_errno > 0
686 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
687 : string_copy(addr->message)
688 : addr->basic_errno > 0
689 ? string_copy(US strerror(addr->basic_errno))
690 : NULL);
691
692 deliver_localpart = save_local;
693 deliver_domain = save_domain;
694 router_name = transport_name = NULL;
695 }
696 #endif
697
698 /*************************************************
699 * Reap SMTP specific responses *
700 *************************************************/
701 static int
smtp_discard_responses(smtp_context * sx,smtp_transport_options_block * ob,int count)702 smtp_discard_responses(smtp_context * sx, smtp_transport_options_block * ob,
703 int count)
704 {
705 uschar flushbuffer[4096];
706
707 while (count-- > 0)
708 {
709 if (!smtp_read_response(sx, flushbuffer, sizeof(flushbuffer),
710 '2', ob->command_timeout)
711 && (errno != 0 || flushbuffer[0] == 0))
712 break;
713 }
714 return count;
715 }
716
717
718 /* Return boolean success */
719
720 static BOOL
smtp_reap_banner(smtp_context * sx)721 smtp_reap_banner(smtp_context * sx)
722 {
723 BOOL good_response;
724 #if defined(__linux__) && defined(TCP_QUICKACK)
725 { /* Hack to get QUICKACK disabled; has to be right after 3whs, and has to on->off */
726 int sock = sx->cctx.sock;
727 struct pollfd p = {.fd = sock, .events = POLLOUT};
728 int rc = poll(&p, 1, 1000);
729 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &on, sizeof(on));
730 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
731 }
732 #endif
733 good_response = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
734 '2', (SOB sx->conn_args.ob)->command_timeout);
735 #ifdef EXPERIMENTAL_DSN_INFO
736 sx->smtp_greeting = string_copy(sx->buffer);
737 #endif
738 return good_response;
739 }
740
741 static BOOL
smtp_reap_ehlo(smtp_context * sx)742 smtp_reap_ehlo(smtp_context * sx)
743 {
744 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
745 (SOB sx->conn_args.ob)->command_timeout))
746 {
747 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
748 {
749 #ifdef EXPERIMENTAL_DSN_INFO
750 sx->helo_response = string_copy(sx->buffer);
751 #endif
752 return FALSE;
753 }
754 sx->esmtp = FALSE;
755 }
756 #ifdef EXPERIMENTAL_DSN_INFO
757 sx->helo_response = string_copy(sx->buffer);
758 #endif
759 #ifndef DISABLE_EVENT
760 (void) event_raise(sx->conn_args.tblock->event_action,
761 US"smtp:ehlo", sx->buffer);
762 #endif
763 return TRUE;
764 }
765
766
767 /******************************************************************************/
768
769 #ifdef EXPERIMENTAL_ESMTP_LIMITS
770 /* If TLS, or TLS not offered, called with the EHLO response in the buffer.
771 Check it for a LIMITS keyword and parse values into the smtp context structure.
772
773 We don't bother with peers that we won't talk TLS to, even though they can,
774 just ignore their LIMITS advice (if any) and treat them as if they do not.
775 This saves us dealing with a duplicate set of values. */
776
777 static void
ehlo_response_limits_read(smtp_context * sx)778 ehlo_response_limits_read(smtp_context * sx)
779 {
780 int ovec[3]; /* results vector for a main-match only */
781
782 /* matches up to just after the first space after the keyword */
783
784 if (pcre_exec(regex_LIMITS, NULL, CS sx->buffer, Ustrlen(sx->buffer),
785 0, PCRE_EOPT, ovec, nelem(ovec)) >= 0)
786 for (const uschar * s = sx->buffer + ovec[1]; *s; )
787 {
788 while (isspace(*s)) s++;
789 if (*s == '\n') break;
790
791 if (strncmpic(s, US"MAILMAX=", 8) == 0)
792 {
793 sx->peer_limit_mail = atoi(CS (s += 8));
794 while (isdigit(*s)) s++;
795 }
796 else if (strncmpic(s, US"RCPTMAX=", 8) == 0)
797 {
798 sx->peer_limit_rcpt = atoi(CS (s += 8));
799 while (isdigit(*s)) s++;
800 }
801 else if (strncmpic(s, US"RCPTDOMAINMAX=", 14) == 0)
802 {
803 sx->peer_limit_rcptdom = atoi(CS (s += 14));
804 while (isdigit(*s)) s++;
805 }
806 else
807 while (*s && !isspace(*s)) s++;
808 }
809 }
810
811 /* Apply given values to the current connection */
812 static void
ehlo_limits_apply(smtp_context * sx,unsigned limit_mail,unsigned limit_rcpt,unsigned limit_rcptdom)813 ehlo_limits_apply(smtp_context * sx,
814 unsigned limit_mail, unsigned limit_rcpt, unsigned limit_rcptdom)
815 {
816 if (limit_mail && limit_mail < sx->max_mail) sx->max_mail = limit_mail;
817 if (limit_rcpt && limit_rcpt < sx->max_rcpt) sx->max_rcpt = limit_rcpt;
818 if (limit_rcptdom)
819 {
820 DEBUG(D_transport) debug_printf("will treat as !multi_domain\n");
821 sx->single_rcpt_domain = TRUE;
822 }
823 }
824
825 /* Apply values from EHLO-resp to the current connection */
826 static void
ehlo_response_limits_apply(smtp_context * sx)827 ehlo_response_limits_apply(smtp_context * sx)
828 {
829 ehlo_limits_apply(sx, sx->peer_limit_mail, sx->peer_limit_rcpt,
830 sx->peer_limit_rcptdom);
831 }
832
833 /* Apply values read from cache to the current connection */
834 static void
ehlo_cache_limits_apply(smtp_context * sx)835 ehlo_cache_limits_apply(smtp_context * sx)
836 {
837 ehlo_limits_apply(sx, sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
838 sx->ehlo_resp.limit_rcptdom);
839 }
840 #endif
841
842 /******************************************************************************/
843
844 #ifndef DISABLE_PIPE_CONNECT
845 static uschar *
ehlo_cache_key(const smtp_context * sx)846 ehlo_cache_key(const smtp_context * sx)
847 {
848 host_item * host = sx->conn_args.host;
849 return Ustrchr(host->address, ':')
850 ? string_sprintf("[%s]:%d.EHLO", host->address,
851 host->port == PORT_NONE ? sx->port : host->port)
852 : string_sprintf("%s:%d.EHLO", host->address,
853 host->port == PORT_NONE ? sx->port : host->port);
854 }
855
856 /* Cache EHLO-response info for use by early-pipe.
857 Called
858 - During a normal flow on EHLO response (either cleartext or under TLS),
859 when we are willing to do PIPE_CONNECT and it is offered
860 - During an early-pipe flow on receiving the actual EHLO response and noting
861 disparity versus the cached info used, when PIPE_CONNECT is still being offered
862
863 We assume that suitable values have been set in the sx.ehlo_resp structure for
864 features and auths; we handle the copy of limits. */
865
866 static void
write_ehlo_cache_entry(smtp_context * sx)867 write_ehlo_cache_entry(smtp_context * sx)
868 {
869 open_db dbblock, * dbm_file;
870
871 #ifdef EXPERIMENTAL_ESMTP_LIMITS
872 sx->ehlo_resp.limit_mail = sx->peer_limit_mail;
873 sx->ehlo_resp.limit_rcpt = sx->peer_limit_rcpt;
874 sx->ehlo_resp.limit_rcptdom = sx->peer_limit_rcptdom;
875 #endif
876
877 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
878 {
879 uschar * ehlo_resp_key = ehlo_cache_key(sx);
880 dbdata_ehlo_resp er = { .data = sx->ehlo_resp };
881
882 HDEBUG(D_transport)
883 #ifdef EXPERIMENTAL_ESMTP_LIMITS
884 if (sx->ehlo_resp.limit_mail || sx->ehlo_resp.limit_rcpt || sx->ehlo_resp.limit_rcptdom)
885 debug_printf("writing clr %04x/%04x cry %04x/%04x lim %05d/%05d/%05d\n",
886 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
887 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths,
888 sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
889 sx->ehlo_resp.limit_rcptdom);
890 else
891 #endif
892 debug_printf("writing clr %04x/%04x cry %04x/%04x\n",
893 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
894 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths);
895
896 dbfn_write(dbm_file, ehlo_resp_key, &er, (int)sizeof(er));
897 dbfn_close(dbm_file);
898 }
899 }
900
901 static void
invalidate_ehlo_cache_entry(smtp_context * sx)902 invalidate_ehlo_cache_entry(smtp_context * sx)
903 {
904 open_db dbblock, * dbm_file;
905
906 if ( sx->early_pipe_active
907 && (dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
908 {
909 uschar * ehlo_resp_key = ehlo_cache_key(sx);
910 dbfn_delete(dbm_file, ehlo_resp_key);
911 dbfn_close(dbm_file);
912 }
913 }
914
915 static BOOL
read_ehlo_cache_entry(smtp_context * sx)916 read_ehlo_cache_entry(smtp_context * sx)
917 {
918 open_db dbblock;
919 open_db * dbm_file;
920
921 if (!(dbm_file = dbfn_open(US"misc", O_RDONLY, &dbblock, FALSE, TRUE)))
922 { DEBUG(D_transport) debug_printf("ehlo-cache: no misc DB\n"); }
923 else
924 {
925 uschar * ehlo_resp_key = ehlo_cache_key(sx);
926 dbdata_ehlo_resp * er;
927
928 if (!(er = dbfn_read_enforce_length(dbm_file, ehlo_resp_key, sizeof(dbdata_ehlo_resp))))
929 { DEBUG(D_transport) debug_printf("no ehlo-resp record\n"); }
930 else if (time(NULL) - er->time_stamp > retry_data_expire)
931 {
932 DEBUG(D_transport) debug_printf("ehlo-resp record too old\n");
933 dbfn_close(dbm_file);
934 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
935 dbfn_delete(dbm_file, ehlo_resp_key);
936 }
937 else
938 {
939 DEBUG(D_transport)
940 #ifdef EXPERIMENTAL_ESMTP_LIMITS
941 if (er->data.limit_mail || er->data.limit_rcpt || er->data.limit_rcptdom)
942 debug_printf("EHLO response bits from cache:"
943 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x lim %05d/%05d/%05d\n",
944 er->data.cleartext_features, er->data.cleartext_auths,
945 er->data.crypted_features, er->data.crypted_auths,
946 er->data.limit_mail, er->data.limit_rcpt, er->data.limit_rcptdom);
947 else
948 #endif
949 debug_printf("EHLO response bits from cache:"
950 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x\n",
951 er->data.cleartext_features, er->data.cleartext_auths,
952 er->data.crypted_features, er->data.crypted_auths);
953
954 sx->ehlo_resp = er->data;
955 #ifdef EXPERIMENTAL_ESMTP_LIMITS
956 ehlo_cache_limits_apply(sx);
957 #endif
958 dbfn_close(dbm_file);
959 return TRUE;
960 }
961 dbfn_close(dbm_file);
962 }
963 return FALSE;
964 }
965
966
967
968 /* Return an auths bitmap for the set of AUTH methods offered by the server
969 which match our authenticators. */
970
971 static unsigned short
study_ehlo_auths(smtp_context * sx)972 study_ehlo_auths(smtp_context * sx)
973 {
974 uschar * names;
975 auth_instance * au;
976 uschar authnum;
977 unsigned short authbits = 0;
978
979 if (!sx->esmtp) return 0;
980 if (!regex_AUTH) regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
981 if (!regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)) return 0;
982 expand_nmax = -1; /* reset */
983 names = string_copyn(expand_nstring[1], expand_nlength[1]);
984
985 for (au = auths, authnum = 0; au; au = au->next, authnum++) if (au->client)
986 {
987 const uschar * list = names;
988 uschar * s;
989 for (int sep = ' '; s = string_nextinlist(&list, &sep, NULL, 0); )
990 if (strcmpic(au->public_name, s) == 0)
991 { authbits |= BIT(authnum); break; }
992 }
993
994 DEBUG(D_transport)
995 debug_printf("server offers %s AUTH, methods '%s', bitmap 0x%04x\n",
996 tls_out.active.sock >= 0 ? "crypted" : "plaintext", names, authbits);
997
998 if (tls_out.active.sock >= 0)
999 sx->ehlo_resp.crypted_auths = authbits;
1000 else
1001 sx->ehlo_resp.cleartext_auths = authbits;
1002 return authbits;
1003 }
1004
1005
1006
1007
1008 /* Wait for and check responses for early-pipelining.
1009
1010 Called from the lower-level smtp_read_response() function
1011 used for general code that assume synchronisation, if context
1012 flags indicate outstanding early-pipelining commands. Also
1013 called fom sync_responses() which handles pipelined commands.
1014
1015 Arguments:
1016 sx smtp connection context
1017 countp number of outstanding responses, adjusted on return
1018
1019 Return:
1020 OK all well
1021 DEFER error on first read of TLS'd conn
1022 FAIL SMTP error in response
1023 */
1024 int
smtp_reap_early_pipe(smtp_context * sx,int * countp)1025 smtp_reap_early_pipe(smtp_context * sx, int * countp)
1026 {
1027 BOOL pending_BANNER = sx->pending_BANNER;
1028 BOOL pending_EHLO = sx->pending_EHLO;
1029 int rc = FAIL;
1030
1031 sx->pending_BANNER = FALSE; /* clear early to avoid recursion */
1032 sx->pending_EHLO = FALSE;
1033
1034 if (pending_BANNER)
1035 {
1036 DEBUG(D_transport) debug_printf("%s expect banner\n", __FUNCTION__);
1037 (*countp)--;
1038 if (!smtp_reap_banner(sx))
1039 {
1040 DEBUG(D_transport) debug_printf("bad banner\n");
1041 if (tls_out.active.sock >= 0) rc = DEFER;
1042 goto fail;
1043 }
1044 }
1045
1046 if (pending_EHLO)
1047 {
1048 unsigned peer_offered;
1049 unsigned short authbits = 0, * ap;
1050
1051 DEBUG(D_transport) debug_printf("%s expect ehlo\n", __FUNCTION__);
1052 (*countp)--;
1053 if (!smtp_reap_ehlo(sx))
1054 {
1055 DEBUG(D_transport) debug_printf("bad response for EHLO\n");
1056 if (tls_out.active.sock >= 0) rc = DEFER;
1057 goto fail;
1058 }
1059
1060 /* Compare the actual EHLO response extensions and AUTH methods to the cached
1061 value we assumed; on difference, dump or rewrite the cache and arrange for a
1062 retry. */
1063
1064 ap = tls_out.active.sock < 0
1065 ? &sx->ehlo_resp.cleartext_auths : &sx->ehlo_resp.crypted_auths;
1066
1067 peer_offered = ehlo_response(sx->buffer,
1068 (tls_out.active.sock < 0 ? OPTION_TLS : 0)
1069 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
1070 | OPTION_UTF8 | OPTION_EARLY_PIPE
1071 );
1072 #ifdef EXPERIMENTAL_ESMTP_LIMITS
1073 if (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1074 ehlo_response_limits_read(sx);
1075 #endif
1076 if ( peer_offered != sx->peer_offered
1077 || (authbits = study_ehlo_auths(sx)) != *ap)
1078 {
1079 HDEBUG(D_transport)
1080 debug_printf("EHLO %s extensions changed, 0x%04x/0x%04x -> 0x%04x/0x%04x\n",
1081 tls_out.active.sock < 0 ? "cleartext" : "crypted",
1082 sx->peer_offered, *ap, peer_offered, authbits);
1083 if (peer_offered & OPTION_EARLY_PIPE)
1084 {
1085 *(tls_out.active.sock < 0
1086 ? &sx->ehlo_resp.cleartext_features : &sx->ehlo_resp.crypted_features) =
1087 peer_offered;
1088 *ap = authbits;
1089 write_ehlo_cache_entry(sx);
1090 }
1091 else
1092 invalidate_ehlo_cache_entry(sx);
1093
1094 return OK; /* just carry on */
1095 }
1096 #ifdef EXPERIMENTAL_ESMTP_LIMITS
1097 /* If we are handling LIMITS, compare the actual EHLO LIMITS values with the
1098 cached values and invalidate cache if different. OK to carry on with
1099 connect since values are advisory. */
1100 {
1101 if ( (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1102 && ( sx->peer_limit_mail != sx->ehlo_resp.limit_mail
1103 || sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt
1104 || sx->peer_limit_rcptdom != sx->ehlo_resp.limit_rcptdom
1105 ) )
1106 {
1107 HDEBUG(D_transport)
1108 {
1109 debug_printf("EHLO LIMITS changed:");
1110 if (sx->peer_limit_mail != sx->ehlo_resp.limit_mail)
1111 debug_printf(" MAILMAX %u -> %u\n", sx->ehlo_resp.limit_mail, sx->peer_limit_mail);
1112 else if (sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt)
1113 debug_printf(" RCPTMAX %u -> %u\n", sx->ehlo_resp.limit_rcpt, sx->peer_limit_rcpt);
1114 else
1115 debug_printf(" RCPTDOMAINMAX %u -> %u\n", sx->ehlo_resp.limit_rcptdom, sx->peer_limit_rcptdom);
1116 }
1117 invalidate_ehlo_cache_entry(sx);
1118 }
1119 }
1120 #endif
1121 }
1122 return OK;
1123
1124 fail:
1125 invalidate_ehlo_cache_entry(sx);
1126 (void) smtp_discard_responses(sx, sx->conn_args.ob, *countp);
1127 return rc;
1128 }
1129 #endif /*!DISABLE_PIPE_CONNECT*/
1130
1131
1132 /*************************************************
1133 * Synchronize SMTP responses *
1134 *************************************************/
1135
1136 /* This function is called from smtp_deliver() to receive SMTP responses from
1137 the server, and match them up with the commands to which they relate. When
1138 PIPELINING is not in use, this function is called after every command, and is
1139 therefore somewhat over-engineered, but it is simpler to use a single scheme
1140 that works both with and without PIPELINING instead of having two separate sets
1141 of code.
1142
1143 The set of commands that are buffered up with pipelining may start with MAIL
1144 and may end with DATA; in between are RCPT commands that correspond to the
1145 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
1146 etc.) are never buffered.
1147
1148 Errors after MAIL or DATA abort the whole process leaving the response in the
1149 buffer. After MAIL, pending responses are flushed, and the original command is
1150 re-instated in big_buffer for error messages. For RCPT commands, the remote is
1151 permitted to reject some recipient addresses while accepting others. However
1152 certain errors clearly abort the whole process. Set the value in
1153 transport_return to PENDING_OK if the address is accepted. If there is a
1154 subsequent general error, it will get reset accordingly. If not, it will get
1155 converted to OK at the end.
1156
1157 Arguments:
1158 sx smtp connection context
1159 count the number of responses to read
1160 pending_DATA 0 if last command sent was not DATA
1161 +1 if previously had a good recipient
1162 -1 if not previously had a good recipient
1163
1164 Returns: 3 if at least one address had 2xx and one had 5xx
1165 2 if at least one address had 5xx but none had 2xx
1166 1 if at least one host had a 2xx response, but none had 5xx
1167 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
1168 -1 timeout while reading RCPT response
1169 -2 I/O or other non-response error for RCPT
1170 -3 DATA or MAIL failed - errno and buffer set
1171 -4 banner or EHLO failed (early-pipelining)
1172 -5 banner or EHLO failed (early-pipelining, TLS)
1173 */
1174
1175 static int
sync_responses(smtp_context * sx,int count,int pending_DATA)1176 sync_responses(smtp_context * sx, int count, int pending_DATA)
1177 {
1178 address_item * addr = sx->sync_addr;
1179 smtp_transport_options_block * ob = sx->conn_args.ob;
1180 int yield = 0;
1181
1182 #ifndef DISABLE_PIPE_CONNECT
1183 int rc;
1184 if ((rc = smtp_reap_early_pipe(sx, &count)) != OK)
1185 return rc == FAIL ? -4 : -5;
1186 #endif
1187
1188 /* Handle the response for a MAIL command. On error, reinstate the original
1189 command in big_buffer for error message use, and flush any further pending
1190 responses before returning, except after I/O errors and timeouts. */
1191
1192 if (sx->pending_MAIL)
1193 {
1194 DEBUG(D_transport) debug_printf("%s expect mail\n", __FUNCTION__);
1195 count--;
1196 sx->pending_MAIL = sx->RCPT_452 = FALSE;
1197 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1198 '2', ob->command_timeout))
1199 {
1200 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
1201 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
1202 if (errno == ERRNO_TLSFAILURE)
1203 return -5;
1204 if (errno == 0 && sx->buffer[0] != 0)
1205 {
1206 int save_errno = 0;
1207 if (sx->buffer[0] == '4')
1208 {
1209 save_errno = ERRNO_MAIL4XX;
1210 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1211 }
1212 count = smtp_discard_responses(sx, ob, count);
1213 errno = save_errno;
1214 }
1215
1216 if (pending_DATA) count--; /* Number of RCPT responses to come */
1217 while (count-- > 0) /* Mark any pending addrs with the host used */
1218 {
1219 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
1220 addr->host_used = sx->conn_args.host;
1221 addr = addr->next;
1222 }
1223 return -3;
1224 }
1225 }
1226
1227 if (pending_DATA) count--; /* Number of RCPT responses to come */
1228
1229 /* Read and handle the required number of RCPT responses, matching each one up
1230 with an address by scanning for the next address whose status is PENDING_DEFER.
1231 */
1232
1233 while (count-- > 0)
1234 {
1235 while (addr->transport_return != PENDING_DEFER)
1236 if (!(addr = addr->next))
1237 return -2;
1238
1239 /* The address was accepted */
1240 addr->host_used = sx->conn_args.host;
1241
1242 DEBUG(D_transport) debug_printf("%s expect rcpt for %s\n", __FUNCTION__, addr->address);
1243 if (smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1244 '2', ob->command_timeout))
1245 {
1246 yield |= 1;
1247 addr->transport_return = PENDING_OK;
1248
1249 /* If af_dr_retry_exists is set, there was a routing delay on this address;
1250 ensure that any address-specific retry record is expunged. We do this both
1251 for the basic key and for the version that also includes the sender. */
1252
1253 if (testflag(addr, af_dr_retry_exists))
1254 {
1255 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
1256 sender_address);
1257 retry_add_item(addr, altkey, rf_delete);
1258 retry_add_item(addr, addr->address_retry_key, rf_delete);
1259 }
1260 }
1261
1262 /* Error on first TLS read */
1263
1264 else if (errno == ERRNO_TLSFAILURE)
1265 return -5;
1266
1267 /* Timeout while reading the response */
1268
1269 else if (errno == ETIMEDOUT)
1270 {
1271 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
1272 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1273 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE, &sx->delivery_start);
1274 retry_add_item(addr, addr->address_retry_key, 0);
1275 update_waiting = FALSE;
1276 return -1;
1277 }
1278
1279 /* Handle other errors in obtaining an SMTP response by returning -1. This
1280 will cause all the addresses to be deferred. Restore the SMTP command in
1281 big_buffer for which we are checking the response, so the error message
1282 makes sense. */
1283
1284 else if (errno != 0 || sx->buffer[0] == 0)
1285 {
1286 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer }, * g = &gs;
1287
1288 /* Use taint-unchecked routines for writing into big_buffer, trusting
1289 that we'll never expand it. */
1290
1291 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, "RCPT TO:<%s>",
1292 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1293 string_from_gstring(g);
1294 return -2;
1295 }
1296
1297 /* Handle SMTP permanent and temporary response codes. */
1298
1299 else
1300 {
1301 addr->message =
1302 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
1303 "%s", transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes),
1304 string_printing(sx->buffer));
1305 setflag(addr, af_pass_message);
1306 if (!sx->verify)
1307 msglog_line(sx->conn_args.host, addr->message);
1308
1309 /* The response was 5xx */
1310
1311 if (sx->buffer[0] == '5')
1312 {
1313 addr->transport_return = FAIL;
1314 yield |= 2;
1315 }
1316
1317 /* The response was 4xx */
1318
1319 else
1320 {
1321 addr->transport_return = DEFER;
1322 addr->basic_errno = ERRNO_RCPT4XX;
1323 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1324
1325 if (!sx->verify)
1326 {
1327 #ifndef DISABLE_EVENT
1328 event_defer_errno = addr->more_errno;
1329 msg_event_raise(US"msg:rcpt:host:defer", addr);
1330 #endif
1331 /* If a 452 and we've had at least one 2xx or 5xx, set next_addr to the
1332 start point for another MAIL command. */
1333
1334 if (addr->more_errno >> 8 == 52 && yield & 3)
1335 {
1336 if (!sx->RCPT_452) /* initialised at MAIL-ack above */
1337 {
1338 DEBUG(D_transport)
1339 debug_printf("%s: seen first 452 too-many-rcpts\n", __FUNCTION__);
1340 sx->RCPT_452 = TRUE;
1341 sx->next_addr = addr;
1342 }
1343 addr->transport_return = PENDING_DEFER;
1344 addr->basic_errno = 0;
1345 }
1346 else
1347 {
1348 /* Log temporary errors if there are more hosts to be tried.
1349 If not, log this last one in the == line. */
1350
1351 if (sx->conn_args.host->next)
1352 if (LOGGING(outgoing_port))
1353 log_write(0, LOG_MAIN, "H=%s [%s]:%d %s", sx->conn_args.host->name,
1354 sx->conn_args.host->address,
1355 sx->port == PORT_NONE ? 25 : sx->port, addr->message);
1356 else
1357 log_write(0, LOG_MAIN, "H=%s [%s]: %s", sx->conn_args.host->name,
1358 sx->conn_args.host->address, addr->message);
1359
1360 #ifndef DISABLE_EVENT
1361 else
1362 msg_event_raise(US"msg:rcpt:defer", addr);
1363 #endif
1364
1365 /* Do not put this message on the list of those waiting for specific
1366 hosts, as otherwise it is likely to be tried too often. */
1367
1368 update_waiting = FALSE;
1369
1370 /* Add a retry item for the address so that it doesn't get tried again
1371 too soon. If address_retry_include_sender is true, add the sender address
1372 to the retry key. */
1373
1374 retry_add_item(addr,
1375 ob->address_retry_include_sender
1376 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
1377 : addr->address_retry_key,
1378 0);
1379 }
1380 }
1381 }
1382 }
1383 if (count && !(addr = addr->next))
1384 return -2;
1385 } /* Loop for next RCPT response */
1386
1387 /* Update where to start at for the next block of responses, unless we
1388 have already handled all the addresses. */
1389
1390 if (addr) sx->sync_addr = addr->next;
1391
1392 /* Handle a response to DATA. If we have not had any good recipients, either
1393 previously or in this block, the response is ignored. */
1394
1395 if (pending_DATA != 0)
1396 {
1397 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1398 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1399 '3', ob->command_timeout))
1400 {
1401 int code;
1402 uschar *msg;
1403 BOOL pass_message;
1404
1405 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1406 return -5;
1407
1408 if (pending_DATA > 0 || (yield & 1) != 0)
1409 {
1410 if (errno == 0 && sx->buffer[0] == '4')
1411 {
1412 errno = ERRNO_DATA4XX;
1413 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1414 }
1415 return -3;
1416 }
1417 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1418 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1419 "is in use and there were no good recipients\n", msg);
1420 }
1421 }
1422
1423 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1424 present) received 3xx. If any RCPTs were handled and yielded anything other
1425 than 4xx, yield will be set non-zero. */
1426
1427 return yield;
1428 }
1429
1430
1431
1432
1433
1434 /* Try an authenticator's client entry */
1435
1436 static int
try_authenticator(smtp_context * sx,auth_instance * au)1437 try_authenticator(smtp_context * sx, auth_instance * au)
1438 {
1439 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1440 host_item * host = sx->conn_args.host; /* host to deliver to */
1441 int rc;
1442
1443 sx->outblock.authenticating = TRUE;
1444 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1445 sx->buffer, sizeof(sx->buffer));
1446 sx->outblock.authenticating = FALSE;
1447 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n", au->name, rc);
1448
1449 /* A temporary authentication failure must hold up delivery to
1450 this host. After a permanent authentication failure, we carry on
1451 to try other authentication methods. If all fail hard, try to
1452 deliver the message unauthenticated unless require_auth was set. */
1453
1454 switch(rc)
1455 {
1456 case OK:
1457 f.smtp_authenticated = TRUE; /* stops the outer loop */
1458 client_authenticator = au->name;
1459 if (au->set_client_id)
1460 client_authenticated_id = expand_string(au->set_client_id);
1461 break;
1462
1463 /* Failure after writing a command */
1464
1465 case FAIL_SEND:
1466 return FAIL_SEND;
1467
1468 /* Failure after reading a response */
1469
1470 case FAIL:
1471 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1472 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1473 au->name, host->name, host->address, sx->buffer);
1474 break;
1475
1476 /* Failure by some other means. In effect, the authenticator
1477 decided it wasn't prepared to handle this case. Typically this
1478 is the result of "fail" in an expansion string. Do we need to
1479 log anything here? Feb 2006: a message is now put in the buffer
1480 if logging is required. */
1481
1482 case CANCELLED:
1483 if (*sx->buffer != 0)
1484 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1485 "authentication H=%s [%s] %s", au->name, host->name,
1486 host->address, sx->buffer);
1487 break;
1488
1489 /* Internal problem, message in buffer. */
1490
1491 case ERROR:
1492 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1493 DEFER, FALSE, &sx->delivery_start);
1494 return ERROR;
1495 }
1496 return OK;
1497 }
1498
1499
1500
1501
1502 /* Do the client side of smtp-level authentication.
1503
1504 Arguments:
1505 sx smtp connection context
1506
1507 sx->buffer should have the EHLO response from server (gets overwritten)
1508
1509 Returns:
1510 OK Success, or failed (but not required): global "smtp_authenticated" set
1511 DEFER Failed authentication (and was required)
1512 ERROR Internal problem
1513
1514 FAIL_SEND Failed communications - transmit
1515 FAIL - response
1516 */
1517
1518 static int
smtp_auth(smtp_context * sx)1519 smtp_auth(smtp_context * sx)
1520 {
1521 host_item * host = sx->conn_args.host; /* host to deliver to */
1522 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1523 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1524 #ifndef DISABLE_PIPE_CONNECT
1525 unsigned short authbits = tls_out.active.sock >= 0
1526 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1527 #endif
1528 uschar * fail_reason = US"server did not advertise AUTH support";
1529
1530 f.smtp_authenticated = FALSE;
1531 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1532
1533 if (!regex_AUTH)
1534 regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
1535
1536 /* Is the server offering AUTH? */
1537
1538 if ( sx->esmtp
1539 &&
1540 #ifndef DISABLE_PIPE_CONNECT
1541 sx->early_pipe_active ? authbits
1542 :
1543 #endif
1544 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1545 )
1546 {
1547 uschar * names = NULL;
1548 expand_nmax = -1; /* reset */
1549
1550 #ifndef DISABLE_PIPE_CONNECT
1551 if (!sx->early_pipe_active)
1552 #endif
1553 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1554
1555 /* Must not do this check until after we have saved the result of the
1556 regex match above as the check could be another RE. */
1557
1558 if ( require_auth == OK
1559 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1560 {
1561 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1562 fail_reason = US"no common mechanisms were found";
1563
1564 #ifndef DISABLE_PIPE_CONNECT
1565 if (sx->early_pipe_active)
1566 {
1567 /* Scan our authenticators (which support use by a client and were offered
1568 by the server (checked at cache-write time)), not suppressed by
1569 client_condition. If one is found, attempt to authenticate by calling its
1570 client function. We are limited to supporting up to 16 authenticator
1571 public-names by the number of bits in a short. */
1572
1573 auth_instance * au;
1574 uschar bitnum;
1575 int rc;
1576
1577 for (bitnum = 0, au = auths;
1578 !f.smtp_authenticated && au && bitnum < 16;
1579 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1580 {
1581 if ( au->client_condition
1582 && !expand_check_condition(au->client_condition, au->name,
1583 US"client authenticator"))
1584 {
1585 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1586 au->name, "client_condition is false");
1587 continue;
1588 }
1589
1590 /* Found data for a listed mechanism. Call its client entry. Set
1591 a flag in the outblock so that data is overwritten after sending so
1592 that reflections don't show it. */
1593
1594 fail_reason = US"authentication attempt(s) failed";
1595
1596 if ((rc = try_authenticator(sx, au)) != OK)
1597 return rc;
1598 }
1599 }
1600 else
1601 #endif
1602
1603 /* Scan the configured authenticators looking for one which is configured
1604 for use as a client, which is not suppressed by client_condition, and
1605 whose name matches an authentication mechanism supported by the server.
1606 If one is found, attempt to authenticate by calling its client function.
1607 */
1608
1609 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1610 {
1611 uschar *p = names;
1612
1613 if ( !au->client
1614 || ( au->client_condition
1615 && !expand_check_condition(au->client_condition, au->name,
1616 US"client authenticator")))
1617 {
1618 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1619 au->name,
1620 (au->client)? "client_condition is false" :
1621 "not configured as a client");
1622 continue;
1623 }
1624
1625 /* Loop to scan supported server mechanisms */
1626
1627 while (*p)
1628 {
1629 int len = Ustrlen(au->public_name);
1630 int rc;
1631
1632 while (isspace(*p)) p++;
1633
1634 if (strncmpic(au->public_name, p, len) != 0 ||
1635 (p[len] != 0 && !isspace(p[len])))
1636 {
1637 while (*p != 0 && !isspace(*p)) p++;
1638 continue;
1639 }
1640
1641 /* Found data for a listed mechanism. Call its client entry. Set
1642 a flag in the outblock so that data is overwritten after sending so
1643 that reflections don't show it. */
1644
1645 fail_reason = US"authentication attempt(s) failed";
1646
1647 if ((rc = try_authenticator(sx, au)) != OK)
1648 return rc;
1649
1650 break; /* If not authenticated, try next authenticator */
1651 } /* Loop for scanning supported server mechanisms */
1652 } /* Loop for further authenticators */
1653 }
1654 }
1655
1656 /* If we haven't authenticated, but are required to, give up. */
1657
1658 if (require_auth == OK && !f.smtp_authenticated)
1659 {
1660 #ifndef DISABLE_PIPE_CONNECT
1661 invalidate_ehlo_cache_entry(sx);
1662 #endif
1663 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1664 string_sprintf("authentication required but %s", fail_reason), DEFER,
1665 FALSE, &sx->delivery_start);
1666 return DEFER;
1667 }
1668
1669 return OK;
1670 }
1671
1672
1673 /* Construct AUTH appendix string for MAIL TO */
1674 /*
1675 Arguments
1676 sx context for smtp connection
1677 p point in sx->buffer to build string
1678 addrlist chain of potential addresses to deliver
1679
1680 Globals f.smtp_authenticated
1681 client_authenticated_sender
1682 Return True on error, otherwise buffer has (possibly empty) terminated string
1683 */
1684
1685 static BOOL
smtp_mail_auth_str(smtp_context * sx,uschar * p,address_item * addrlist)1686 smtp_mail_auth_str(smtp_context * sx, uschar * p, address_item * addrlist)
1687 {
1688 smtp_transport_options_block * ob = sx->conn_args.ob;
1689 uschar * local_authenticated_sender = authenticated_sender;
1690
1691 #ifdef notdef
1692 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n",
1693 authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1694 #endif
1695
1696 if (ob->authenticated_sender)
1697 {
1698 uschar * new = expand_string(ob->authenticated_sender);
1699 if (!new)
1700 {
1701 if (!f.expand_string_forcedfail)
1702 {
1703 uschar *message = string_sprintf("failed to expand "
1704 "authenticated_sender: %s", expand_string_message);
1705 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
1706 return TRUE;
1707 }
1708 }
1709 else if (*new)
1710 local_authenticated_sender = new;
1711 }
1712
1713 /* Add the authenticated sender address if present */
1714
1715 if ( (f.smtp_authenticated || ob->authenticated_sender_force)
1716 && local_authenticated_sender)
1717 {
1718 string_format_nt(p, sizeof(sx->buffer) - (p-sx->buffer), " AUTH=%s",
1719 auth_xtextencode(local_authenticated_sender,
1720 Ustrlen(local_authenticated_sender)));
1721 client_authenticated_sender = string_copy(local_authenticated_sender);
1722 }
1723 else
1724 *p = 0;
1725
1726 return FALSE;
1727 }
1728
1729
1730
1731 typedef struct smtp_compare_s
1732 {
1733 uschar * current_sender_address;
1734 struct transport_instance * tblock;
1735 } smtp_compare_t;
1736
1737
1738 /* Create a unique string that identifies this message, it is based on
1739 sender_address, helo_data and tls_certificate if enabled.
1740 */
1741
1742 static uschar *
smtp_local_identity(uschar * sender,struct transport_instance * tblock)1743 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1744 {
1745 address_item * addr1;
1746 uschar * if1 = US"";
1747 uschar * helo1 = US"";
1748 #ifndef DISABLE_TLS
1749 uschar * tlsc1 = US"";
1750 #endif
1751 uschar * save_sender_address = sender_address;
1752 uschar * local_identity = NULL;
1753 smtp_transport_options_block * ob = SOB tblock->options_block;
1754
1755 sender_address = sender;
1756
1757 addr1 = deliver_make_addr (sender, TRUE);
1758 deliver_set_expansions(addr1);
1759
1760 if (ob->interface)
1761 if1 = expand_string(ob->interface);
1762
1763 if (ob->helo_data)
1764 helo1 = expand_string(ob->helo_data);
1765
1766 #ifndef DISABLE_TLS
1767 if (ob->tls_certificate)
1768 tlsc1 = expand_string(ob->tls_certificate);
1769 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1770 #else
1771 local_identity = string_sprintf ("%s^%s", if1, helo1);
1772 #endif
1773
1774 deliver_set_expansions(NULL);
1775 sender_address = save_sender_address;
1776
1777 return local_identity;
1778 }
1779
1780
1781
1782 /* This routine is a callback that is called from transport_check_waiting.
1783 This function will evaluate the incoming message versus the previous
1784 message. If the incoming message is using a different local identity then
1785 we will veto this new message. */
1786
1787 static BOOL
smtp_are_same_identities(uschar * message_id,smtp_compare_t * s_compare)1788 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1789 {
1790 uschar * message_local_identity,
1791 * current_local_identity,
1792 * new_sender_address;
1793
1794 current_local_identity =
1795 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1796
1797 if (!(new_sender_address = spool_sender_from_msgid(message_id)))
1798 return FALSE;
1799
1800
1801 message_local_identity =
1802 smtp_local_identity(new_sender_address, s_compare->tblock);
1803
1804 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1805 }
1806
1807
1808
1809 static unsigned
ehlo_response(uschar * buf,unsigned checks)1810 ehlo_response(uschar * buf, unsigned checks)
1811 {
1812 size_t bsize = Ustrlen(buf);
1813
1814 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1815
1816 #ifndef DISABLE_TLS
1817 if ( checks & OPTION_TLS
1818 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1819 #endif
1820 checks &= ~OPTION_TLS;
1821
1822 if ( checks & OPTION_IGNQ
1823 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1824 PCRE_EOPT, NULL, 0) < 0)
1825 checks &= ~OPTION_IGNQ;
1826
1827 if ( checks & OPTION_CHUNKING
1828 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1829 checks &= ~OPTION_CHUNKING;
1830
1831 #ifndef DISABLE_PRDR
1832 if ( checks & OPTION_PRDR
1833 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1834 #endif
1835 checks &= ~OPTION_PRDR;
1836
1837 #ifdef SUPPORT_I18N
1838 if ( checks & OPTION_UTF8
1839 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1840 #endif
1841 checks &= ~OPTION_UTF8;
1842
1843 if ( checks & OPTION_DSN
1844 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1845 checks &= ~OPTION_DSN;
1846
1847 if ( checks & OPTION_PIPE
1848 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1849 PCRE_EOPT, NULL, 0) < 0)
1850 checks &= ~OPTION_PIPE;
1851
1852 if ( checks & OPTION_SIZE
1853 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1854 checks &= ~OPTION_SIZE;
1855
1856 #ifndef DISABLE_PIPE_CONNECT
1857 if ( checks & OPTION_EARLY_PIPE
1858 && pcre_exec(regex_EARLY_PIPE, NULL, CS buf, bsize, 0,
1859 PCRE_EOPT, NULL, 0) < 0)
1860 #endif
1861 checks &= ~OPTION_EARLY_PIPE;
1862
1863 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1864 return checks;
1865 }
1866
1867
1868
1869 /* Callback for emitting a BDAT data chunk header.
1870
1871 If given a nonzero size, first flush any buffered SMTP commands
1872 then emit the command.
1873
1874 Reap previous SMTP command responses if requested, and always reap
1875 the response from a previous BDAT command.
1876
1877 Args:
1878 tctx transport context
1879 chunk_size value for SMTP BDAT command
1880 flags
1881 tc_chunk_last add LAST option to SMTP BDAT command
1882 tc_reap_prev reap response to previous SMTP commands
1883
1884 Returns:
1885 OK or ERROR
1886 DEFER TLS error on first read (EHLO-resp); errno set
1887 */
1888
1889 static int
smtp_chunk_cmd_callback(transport_ctx * tctx,unsigned chunk_size,unsigned flags)1890 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1891 unsigned flags)
1892 {
1893 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1894 smtp_context * sx = tctx->smtp_context;
1895 int cmd_count = 0;
1896 int prev_cmd_count;
1897
1898 /* Write SMTP chunk header command. If not reaping responses, note that
1899 there may be more writes (like, the chunk data) done soon. */
1900
1901 if (chunk_size > 0)
1902 {
1903 #ifndef DISABLE_PIPE_CONNECT
1904 BOOL new_conn = !!(sx->outblock.conn_args);
1905 #endif
1906 if((cmd_count = smtp_write_command(sx,
1907 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1908 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1909 ) < 0) return ERROR;
1910 if (flags & tc_chunk_last)
1911 data_command = string_copy(big_buffer); /* Save for later error message */
1912 #ifndef DISABLE_PIPE_CONNECT
1913 /* That command write could have been the one that made the connection.
1914 Copy the fd from the client conn ctx (smtp transport specific) to the
1915 generic transport ctx. */
1916
1917 if (new_conn)
1918 tctx->u.fd = sx->outblock.cctx->sock;
1919 #endif
1920 }
1921
1922 prev_cmd_count = cmd_count += sx->cmd_count;
1923
1924 /* Reap responses for any previous, but not one we just emitted */
1925
1926 if (chunk_size > 0)
1927 prev_cmd_count--;
1928 if (sx->pending_BDAT)
1929 prev_cmd_count--;
1930
1931 if (flags & tc_reap_prev && prev_cmd_count > 0)
1932 {
1933 DEBUG(D_transport) debug_printf("look for %d responses"
1934 " for previous pipelined cmds\n", prev_cmd_count);
1935
1936 switch(sync_responses(sx, prev_cmd_count, 0))
1937 {
1938 case 1: /* 2xx (only) => OK */
1939 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1940 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1941 case 0: break; /* No 2xx or 5xx, but no probs */
1942
1943 case -5: errno = ERRNO_TLSFAILURE;
1944 return DEFER;
1945 #ifndef DISABLE_PIPE_CONNECT
1946 case -4: /* non-2xx for pipelined banner or EHLO */
1947 #endif
1948 case -1: /* Timeout on RCPT */
1949 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1950 }
1951 cmd_count = 1;
1952 if (!sx->pending_BDAT)
1953 pipelining_active = FALSE;
1954 }
1955
1956 /* Reap response for an outstanding BDAT */
1957
1958 if (sx->pending_BDAT)
1959 {
1960 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1961
1962 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
1963 ob->command_timeout))
1964 {
1965 if (errno == 0 && sx->buffer[0] == '4')
1966 {
1967 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1968 sx->addrlist->more_errno |=
1969 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1970 }
1971 return ERROR;
1972 }
1973 cmd_count--;
1974 sx->pending_BDAT = FALSE;
1975 pipelining_active = FALSE;
1976 }
1977 else if (chunk_size > 0)
1978 sx->pending_BDAT = TRUE;
1979
1980
1981 sx->cmd_count = cmd_count;
1982 return OK;
1983 }
1984
1985
1986
1987 /*************************************************
1988 * Make connection for given message *
1989 *************************************************/
1990
1991 /*
1992 Arguments:
1993 sx connection context
1994 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1995 a second attempt after TLS initialization fails
1996
1997 Returns: OK - the connection was made and the delivery attempted;
1998 fd is set in the conn context, tls_out set up.
1999 DEFER - the connection could not be made, or something failed
2000 while setting up the SMTP session, or there was a
2001 non-message-specific error, such as a timeout.
2002 ERROR - helo_data or add_headers or authenticated_sender is
2003 specified for this transport, and the string failed
2004 to expand
2005 */
2006 int
smtp_setup_conn(smtp_context * sx,BOOL suppress_tls)2007 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
2008 {
2009 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
2010 BOOL pass_message = FALSE;
2011 uschar * message = NULL;
2012 int yield = OK;
2013 #ifndef DISABLE_TLS
2014 uschar * tls_errstr;
2015 #endif
2016
2017 sx->conn_args.ob = ob;
2018
2019 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
2020 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
2021 /* sx->ok = FALSE; */
2022 sx->send_rset = TRUE;
2023 sx->send_quit = TRUE;
2024 sx->setting_up = TRUE;
2025 sx->esmtp = TRUE;
2026 /* sx->esmtp_sent = FALSE; */
2027 #ifdef SUPPORT_I18N
2028 /* sx->utf8_needed = FALSE; */
2029 #endif
2030 sx->dsn_all_lasthop = TRUE;
2031 #ifdef SUPPORT_DANE
2032 /* sx->conn_args.dane = FALSE; */
2033 sx->dane_required =
2034 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
2035 #endif
2036 #ifndef DISABLE_PIPE_CONNECT
2037 /* sx->early_pipe_active = sx->early_pipe_ok = FALSE; */
2038 /* sx->ehlo_resp.cleartext_features = sx->ehlo_resp.crypted_features = 0; */
2039 /* sx->pending_BANNER = sx->pending_EHLO = sx->pending_MAIL = FALSE; */
2040 #endif
2041
2042 if ((sx->max_mail = sx->conn_args.tblock->connection_max_messages) == 0) sx->max_mail = 999999;
2043 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
2044 /* sx->peer_offered = 0; */
2045 /* sx->avoid_option = 0; */
2046 sx->igquotstr = US"";
2047 if (!sx->helo_data) sx->helo_data = ob->helo_data;
2048 #ifdef EXPERIMENTAL_DSN_INFO
2049 /* sx->smtp_greeting = NULL; */
2050 /* sx->helo_response = NULL; */
2051 #endif
2052
2053 smtp_command = US"initial connection";
2054 /* sx->buffer[0] = '\0'; */
2055
2056 /* Set up the buffer for reading SMTP response packets. */
2057
2058 sx->inblock.buffer = sx->inbuffer;
2059 sx->inblock.buffersize = sizeof(sx->inbuffer);
2060 sx->inblock.ptr = sx->inbuffer;
2061 sx->inblock.ptrend = sx->inbuffer;
2062
2063 /* Set up the buffer for holding SMTP commands while pipelining */
2064
2065 sx->outblock.buffer = sx->outbuffer;
2066 sx->outblock.buffersize = sizeof(sx->outbuffer);
2067 sx->outblock.ptr = sx->outbuffer;
2068 /* sx->outblock.cmd_count = 0; */
2069 /* sx->outblock.authenticating = FALSE; */
2070 /* sx->outblock.conn_args = NULL; */
2071
2072 /* Reset the parameters of a TLS session. */
2073
2074 tls_out.bits = 0;
2075 tls_out.cipher = NULL; /* the one we may use for this transport */
2076 tls_out.ourcert = NULL;
2077 tls_out.peercert = NULL;
2078 tls_out.peerdn = NULL;
2079 #ifdef USE_OPENSSL
2080 tls_out.sni = NULL;
2081 #endif
2082 tls_out.ocsp = OCSP_NOT_REQ;
2083 #ifndef DISABLE_TLS_RESUME
2084 tls_out.resumption = 0;
2085 #endif
2086 tls_out.ver = NULL;
2087
2088 /* Flip the legacy TLS-related variables over to the outbound set in case
2089 they're used in the context of the transport. Don't bother resetting
2090 afterward (when being used by a transport) as we're in a subprocess.
2091 For verify, unflipped once the callout is dealt with */
2092
2093 tls_modify_variables(&tls_out);
2094
2095 #ifdef DISABLE_TLS
2096 if (sx->smtps)
2097 {
2098 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
2099 DEFER, FALSE, &sx->delivery_start);
2100 return ERROR;
2101 }
2102 #else
2103
2104 /* If we have a proxied TLS connection, check usability for this message */
2105
2106 if (continue_hostname && continue_proxy_cipher)
2107 {
2108 int rc;
2109 const uschar * sni = US"";
2110
2111 # ifdef SUPPORT_DANE
2112 /* Check if the message will be DANE-verified; if so force its SNI */
2113
2114 tls_out.dane_verified = FALSE;
2115 smtp_port_for_connect(sx->conn_args.host, sx->port);
2116 if ( sx->conn_args.host->dnssec == DS_YES
2117 && ( sx->dane_required
2118 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2119 ) )
2120 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2121 {
2122 case OK: sx->conn_args.dane = TRUE;
2123 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2124 ob->tls_sni = sx->conn_args.host->name; /* force SNI */
2125 break;
2126 case FAIL_FORCED: break;
2127 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2128 string_sprintf("DANE error: tlsa lookup %s",
2129 rc_to_string(rc)),
2130 rc, FALSE, &sx->delivery_start);
2131 # ifndef DISABLE_EVENT
2132 (void) event_raise(sx->conn_args.tblock->event_action,
2133 US"dane:fail", sx->dane_required
2134 ? US"dane-required" : US"dnssec-invalid");
2135 # endif
2136 return rc;
2137 }
2138 # endif
2139
2140 /* If the SNI or the DANE status required for the new message differs from the
2141 existing conn drop the connection to force a new one. */
2142
2143 if (ob->tls_sni && !(sni = expand_cstring(ob->tls_sni)))
2144 log_write(0, LOG_MAIN|LOG_PANIC,
2145 "<%s>: failed to expand transport's tls_sni value: %s",
2146 sx->addrlist->address, expand_string_message);
2147
2148 # ifdef SUPPORT_DANE
2149 if ( (continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni)
2150 && continue_proxy_dane == sx->conn_args.dane)
2151 {
2152 tls_out.sni = US sni;
2153 if ((tls_out.dane_verified = continue_proxy_dane))
2154 sx->conn_args.host->dnssec = DS_YES;
2155 }
2156 # else
2157 if ((continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni))
2158 tls_out.sni = US sni;
2159 # endif
2160 else
2161 {
2162 DEBUG(D_transport)
2163 debug_printf("Closing proxied-TLS connection due to SNI mismatch\n");
2164
2165 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP>> QUIT\n");
2166 write(0, "QUIT\r\n", 6);
2167 close(0);
2168 continue_hostname = continue_proxy_cipher = NULL;
2169 f.continue_more = FALSE;
2170 continue_sequence = 1; /* Unfortunately, this process cannot affect success log
2171 which is done by delivery proc. Would have to pass this
2172 back through reporting pipe. */
2173 }
2174 }
2175 #endif /*!DISABLE_TLS*/
2176
2177 /* Make a connection to the host if this isn't a continued delivery, and handle
2178 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2179 specially so they can be identified for retries. */
2180
2181 if (!continue_hostname)
2182 {
2183 if (sx->verify)
2184 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2185
2186 /* Arrange to report to calling process this is a new connection */
2187
2188 clearflag(sx->first_addr, af_cont_conn);
2189 setflag(sx->first_addr, af_new_conn);
2190
2191 /* Get the actual port the connection will use, into sx->conn_args.host */
2192
2193 smtp_port_for_connect(sx->conn_args.host, sx->port);
2194
2195 #ifdef SUPPORT_DANE
2196 /* Do TLSA lookup for DANE */
2197 {
2198 tls_out.dane_verified = FALSE;
2199 tls_out.tlsa_usage = 0;
2200
2201 if (sx->conn_args.host->dnssec == DS_YES)
2202 {
2203 int rc;
2204 if( sx->dane_required
2205 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2206 )
2207 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2208 {
2209 case OK: sx->conn_args.dane = TRUE;
2210 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2211 ob->tls_sni = sx->conn_args.host->name; /* force SNI */
2212 break;
2213 case FAIL_FORCED: break;
2214 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2215 string_sprintf("DANE error: tlsa lookup %s",
2216 rc_to_string(rc)),
2217 rc, FALSE, &sx->delivery_start);
2218 # ifndef DISABLE_EVENT
2219 (void) event_raise(sx->conn_args.tblock->event_action,
2220 US"dane:fail", sx->dane_required
2221 ? US"dane-required" : US"dnssec-invalid");
2222 # endif
2223 return rc;
2224 }
2225 }
2226 else if (sx->dane_required)
2227 {
2228 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2229 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2230 FAIL, FALSE, &sx->delivery_start);
2231 # ifndef DISABLE_EVENT
2232 (void) event_raise(sx->conn_args.tblock->event_action,
2233 US"dane:fail", US"dane-required");
2234 # endif
2235 return FAIL;
2236 }
2237 }
2238 #endif /*DANE*/
2239
2240 /* Make the TCP connection */
2241
2242 sx->cctx.tls_ctx = NULL;
2243 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2244 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2245 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom =
2246 #endif
2247 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2248
2249 #ifndef DISABLE_PIPE_CONNECT
2250 if ( verify_check_given_host(CUSS &ob->hosts_pipe_connect,
2251 sx->conn_args.host) == OK)
2252
2253 /* We don't find out the local ip address until the connect, so if
2254 the helo string might use it avoid doing early-pipelining. */
2255
2256 if ( !sx->helo_data
2257 || !Ustrstr(sx->helo_data, "$sending_ip_address")
2258 || Ustrstr(sx->helo_data, "def:sending_ip_address")
2259 )
2260 {
2261 sx->early_pipe_ok = TRUE;
2262 if ( read_ehlo_cache_entry(sx)
2263 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2264 {
2265 DEBUG(D_transport)
2266 debug_printf("Using cached cleartext PIPE_CONNECT\n");
2267 sx->early_pipe_active = TRUE;
2268 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2269 }
2270 }
2271 else DEBUG(D_transport)
2272 debug_printf("helo needs $sending_ip_address\n");
2273
2274 PIPE_CONNECT_RETRY:
2275 if (sx->early_pipe_active)
2276 sx->outblock.conn_args = &sx->conn_args;
2277 else
2278 #endif
2279 {
2280 blob lazy_conn = {.data = NULL};
2281 /* For TLS-connect, a TFO lazy-connect is useful since the Client Hello
2282 can go on the TCP SYN. */
2283
2284 if ((sx->cctx.sock = smtp_connect(&sx->conn_args,
2285 sx->smtps ? &lazy_conn : NULL)) < 0)
2286 {
2287 set_errno_nohost(sx->addrlist,
2288 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2289 sx->verify ? US strerror(errno) : NULL,
2290 DEFER, FALSE, &sx->delivery_start);
2291 sx->send_quit = FALSE;
2292 return DEFER;
2293 }
2294 #ifdef TCP_QUICKACK
2295 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2296 sizeof(off));
2297 #endif
2298 }
2299 /* Expand the greeting message while waiting for the initial response. (Makes
2300 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2301 delayed till here so that $sending_interface and $sending_port are set. */
2302 /*XXX early-pipe: they still will not be. Is there any way to find out what they
2303 will be? Somehow I doubt it. */
2304
2305 if (sx->helo_data)
2306 if (!(sx->helo_data = expand_string(sx->helo_data)))
2307 if (sx->verify)
2308 log_write(0, LOG_MAIN|LOG_PANIC,
2309 "<%s>: failed to expand transport's helo_data value for callout: %s",
2310 sx->addrlist->address, expand_string_message);
2311
2312 #ifdef SUPPORT_I18N
2313 if (sx->helo_data)
2314 {
2315 expand_string_message = NULL;
2316 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2317 &expand_string_message)),
2318 expand_string_message)
2319 if (sx->verify)
2320 log_write(0, LOG_MAIN|LOG_PANIC,
2321 "<%s>: failed to expand transport's helo_data value for callout: %s",
2322 sx->addrlist->address, expand_string_message);
2323 else
2324 sx->helo_data = NULL;
2325 }
2326 #endif
2327
2328 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2329 is nevertheless a reasonably clean way of programming this kind of logic,
2330 where you want to escape on any error. */
2331
2332 if (!sx->smtps)
2333 {
2334 #ifndef DISABLE_PIPE_CONNECT
2335 if (sx->early_pipe_active)
2336 {
2337 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2338 sx->outblock.cmd_count = 1;
2339 }
2340 else
2341 #endif
2342 {
2343 if (!smtp_reap_banner(sx))
2344 goto RESPONSE_FAILED;
2345 }
2346
2347 #ifndef DISABLE_EVENT
2348 {
2349 uschar * s;
2350 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2351 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2352 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer);
2353 if (s)
2354 {
2355 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2356 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2357 DEFER, FALSE, &sx->delivery_start);
2358 yield = DEFER;
2359 goto SEND_QUIT;
2360 }
2361 }
2362 #endif
2363
2364 /* Now check if the helo_data expansion went well, and sign off cleanly if
2365 it didn't. */
2366
2367 if (!sx->helo_data)
2368 {
2369 message = string_sprintf("failed to expand helo_data: %s",
2370 expand_string_message);
2371 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2372 yield = DEFER;
2373 goto SEND_QUIT;
2374 }
2375 }
2376
2377 /** Debugging without sending a message
2378 sx->addrlist->transport_return = DEFER;
2379 goto SEND_QUIT;
2380 **/
2381
2382 /* Errors that occur after this point follow an SMTP command, which is
2383 left in big_buffer by smtp_write_command() for use in error messages. */
2384
2385 smtp_command = big_buffer;
2386
2387 /* Tell the remote who we are...
2388
2389 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2390 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2391 greeting is of this form. The assumption was that the far end supports it
2392 properly... but experience shows that there are some that give 5xx responses,
2393 even though the banner includes "ESMTP" (there's a bloody-minded one that
2394 says "ESMTP not spoken here"). Cope with that case.
2395
2396 September 2000: Time has passed, and it seems reasonable now to always send
2397 EHLO at the start. It is also convenient to make the change while installing
2398 the TLS stuff.
2399
2400 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2401 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2402 would be no way to send out the mails, so there is now a host list
2403 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2404 PIPELINING problem as well. Maybe it can also be useful to cure other
2405 problems with broken servers.
2406
2407 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2408 Then somebody tried it with a Microsoft mailer... It seems that all other
2409 mailers use upper case for some reason (the RFC is quite clear about case
2410 independence) so, for peace of mind, I gave in. */
2411
2412 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2413
2414 /* Alas; be careful, since this goto is not an error-out, so conceivably
2415 we might set data between here and the target which we assume to exist
2416 and be usable. I can see this coming back to bite us. */
2417 #ifndef DISABLE_TLS
2418 if (sx->smtps)
2419 {
2420 smtp_peer_options |= OPTION_TLS;
2421 suppress_tls = FALSE;
2422 ob->tls_tempfail_tryclear = FALSE;
2423 smtp_command = US"SSL-on-connect";
2424 goto TLS_NEGOTIATE;
2425 }
2426 #endif
2427
2428 if (sx->esmtp)
2429 {
2430 if (smtp_write_command(sx,
2431 #ifndef DISABLE_PIPE_CONNECT
2432 sx->early_pipe_active ? SCMD_BUFFER :
2433 #endif
2434 SCMD_FLUSH,
2435 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2436 goto SEND_FAILED;
2437 sx->esmtp_sent = TRUE;
2438
2439 #ifndef DISABLE_PIPE_CONNECT
2440 if (sx->early_pipe_active)
2441 {
2442 sx->pending_EHLO = TRUE;
2443
2444 /* If we have too many authenticators to handle and might need to AUTH
2445 for this transport, pipeline no further as we will need the
2446 list of auth methods offered. Reap the banner and EHLO. */
2447
2448 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2449 && f.smtp_in_early_pipe_no_auth)
2450 {
2451 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2452 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2453 goto SEND_FAILED;
2454 if (sync_responses(sx, 2, 0) != 0)
2455 {
2456 HDEBUG(D_transport)
2457 debug_printf("failed reaping pipelined cmd responses\n");
2458 goto RESPONSE_FAILED;
2459 }
2460 sx->early_pipe_active = FALSE;
2461 }
2462 }
2463 else
2464 #endif
2465 if (!smtp_reap_ehlo(sx))
2466 goto RESPONSE_FAILED;
2467 }
2468 else
2469 DEBUG(D_transport)
2470 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2471
2472 #ifndef DISABLE_PIPE_CONNECT
2473 if (!sx->early_pipe_active)
2474 #endif
2475 if (!sx->esmtp)
2476 {
2477 BOOL good_response;
2478 int n = sizeof(sx->buffer);
2479 uschar * rsp = sx->buffer;
2480
2481 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer) + 1) < sizeof(sx->buffer)/2)
2482 { rsp = sx->buffer + n; n = sizeof(sx->buffer) - n; }
2483
2484 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2485 goto SEND_FAILED;
2486 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2487 #ifdef EXPERIMENTAL_DSN_INFO
2488 sx->helo_response = string_copy(rsp);
2489 #endif
2490 if (!good_response)
2491 {
2492 /* Handle special logging for a closed connection after HELO
2493 when had previously sent EHLO */
2494
2495 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2496 {
2497 errno = ERRNO_SMTPCLOSED;
2498 goto EHLOHELO_FAILED;
2499 }
2500 memmove(sx->buffer, rsp, Ustrlen(rsp));
2501 goto RESPONSE_FAILED;
2502 }
2503 }
2504
2505 if (sx->esmtp || sx->lmtp)
2506 {
2507 #ifndef DISABLE_PIPE_CONNECT
2508 if (!sx->early_pipe_active)
2509 #endif
2510 {
2511 sx->peer_offered = ehlo_response(sx->buffer,
2512 OPTION_TLS /* others checked later */
2513 #ifndef DISABLE_PIPE_CONNECT
2514 | (sx->early_pipe_ok
2515 ? OPTION_IGNQ
2516 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2517 #ifdef SUPPORT_I18N
2518 | OPTION_UTF8
2519 #endif
2520 | OPTION_EARLY_PIPE
2521 : 0
2522 )
2523 #endif
2524 );
2525 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2526 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2527 {
2528 ehlo_response_limits_read(sx);
2529 ehlo_response_limits_apply(sx);
2530 }
2531 #endif
2532 #ifndef DISABLE_PIPE_CONNECT
2533 if (sx->early_pipe_ok)
2534 {
2535 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2536
2537 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2538 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2539 {
2540 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2541 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2542 write_ehlo_cache_entry(sx);
2543 }
2544 }
2545 #endif
2546 }
2547
2548 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2549
2550 #ifndef DISABLE_TLS
2551 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2552 #endif
2553 }
2554 }
2555
2556 /* For continuing deliveries down the same channel, having re-exec'd the socket
2557 is the standard input; for a socket held open from verify it is recorded
2558 in the cutthrough context block. Either way we don't need to redo EHLO here
2559 (but may need to do so for TLS - see below).
2560 Set up the pointer to where subsequent commands will be left, for
2561 error messages. Note that smtp_peer_options will have been
2562 set from the command line if they were set in the process that passed the
2563 connection on. */
2564
2565 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2566 as the continue goes via transport_pass_socket() and doublefork and exec.
2567 It does not wait. Unclear how we keep separate host's responses
2568 separate - we could match up by host ip+port as a bodge. */
2569
2570 else
2571 {
2572 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2573 {
2574 sx->cctx = cutthrough.cctx;
2575 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2576 }
2577 else
2578 {
2579 sx->cctx.sock = 0; /* stdin */
2580 sx->cctx.tls_ctx = NULL;
2581 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2582 }
2583 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2584 smtp_command = big_buffer;
2585 sx->peer_offered = smtp_peer_options;
2586 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2587 /* Limits passed by cmdline over exec. */
2588 ehlo_limits_apply(sx,
2589 sx->peer_limit_mail = continue_limit_mail,
2590 sx->peer_limit_rcpt = continue_limit_rcpt,
2591 sx->peer_limit_rcptdom = continue_limit_rcptdom);
2592 #endif
2593 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2594
2595 /* For a continued connection with TLS being proxied for us, or a
2596 held-open verify connection with TLS, nothing more to do. */
2597
2598 if ( continue_proxy_cipher
2599 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2600 && cutthrough.is_tls)
2601 )
2602 {
2603 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2604 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2605 continue_proxy_cipher ? "proxied" : "verify conn with");
2606 return OK;
2607 }
2608 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2609 }
2610
2611 /* If TLS is available on this connection, whether continued or not, attempt to
2612 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2613 send another EHLO - the server may give a different answer in secure mode. We
2614 use a separate buffer for reading the response to STARTTLS so that if it is
2615 negative, the original EHLO data is available for subsequent analysis, should
2616 the client not be required to use TLS. If the response is bad, copy the buffer
2617 for error analysis. */
2618
2619 #ifndef DISABLE_TLS
2620 if ( smtp_peer_options & OPTION_TLS
2621 && !suppress_tls
2622 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2623 && ( !sx->verify
2624 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2625 ) )
2626 {
2627 uschar buffer2[4096];
2628
2629 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2630 goto SEND_FAILED;
2631
2632 #ifndef DISABLE_PIPE_CONNECT
2633 /* If doing early-pipelining reap the banner and EHLO-response but leave
2634 the response for the STARTTLS we just sent alone. On fail, assume wrong
2635 cached capability and retry with the pipelining disabled. */
2636
2637 if (sx->early_pipe_active && sync_responses(sx, 2, 0) != 0)
2638 {
2639 HDEBUG(D_transport)
2640 debug_printf("failed reaping pipelined cmd responses\n");
2641 close(sx->cctx.sock);
2642 sx->cctx.sock = -1;
2643 sx->early_pipe_active = FALSE;
2644 goto PIPE_CONNECT_RETRY;
2645 }
2646 #endif
2647
2648 /* If there is an I/O error, transmission of this message is deferred. If
2649 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2650 false, we also defer. However, if there is a temporary rejection of STARTTLS
2651 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2652 STARTTLS, we carry on. This means we will try to send the message in clear,
2653 unless the host is in hosts_require_tls (tested below). */
2654
2655 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2656 {
2657 if ( errno != 0
2658 || buffer2[0] == 0
2659 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2660 )
2661 {
2662 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2663 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2664 goto RESPONSE_FAILED;
2665 }
2666 }
2667
2668 /* STARTTLS accepted: try to negotiate a TLS session. */
2669
2670 else
2671 TLS_NEGOTIATE:
2672 {
2673 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2674 {
2675 /* TLS negotiation failed; give an error. From outside, this function may
2676 be called again to try in clear on a new connection, if the options permit
2677 it for this host. */
2678 TLS_CONN_FAILED:
2679 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2680
2681 # ifdef SUPPORT_DANE
2682 if (sx->conn_args.dane)
2683 {
2684 log_write(0, LOG_MAIN,
2685 "DANE attempt failed; TLS connection to %s [%s]: %s",
2686 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2687 # ifndef DISABLE_EVENT
2688 (void) event_raise(sx->conn_args.tblock->event_action,
2689 US"dane:fail", US"validation-failure"); /* could do with better detail */
2690 # endif
2691 }
2692 # endif
2693
2694 errno = ERRNO_TLSFAILURE;
2695 message = string_sprintf("TLS session: %s", tls_errstr);
2696 sx->send_quit = FALSE;
2697 goto TLS_FAILED;
2698 }
2699 sx->send_tlsclose = TRUE;
2700
2701 /* TLS session is set up. Check the inblock fill level. If there is
2702 content then as we have not yet done a tls read it must have arrived before
2703 the TLS handshake, in-clear. That violates the sync requirement of the
2704 STARTTLS RFC, so fail. */
2705
2706 if (sx->inblock.ptr != sx->inblock.ptrend)
2707 {
2708 DEBUG(D_tls)
2709 {
2710 int i = sx->inblock.ptrend - sx->inblock.ptr;
2711 debug_printf("unused data in input buffer after ack for STARTTLS:\n"
2712 "'%.*s'%s\n",
2713 i > 100 ? 100 : i, sx->inblock.ptr, i > 100 ? "..." : "");
2714 }
2715 tls_errstr = US"synch error before connect";
2716 goto TLS_CONN_FAILED;
2717 }
2718
2719 smtp_peer_options_wrap = smtp_peer_options;
2720 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2721 if (addr->transport_return == PENDING_DEFER)
2722 {
2723 addr->cipher = tls_out.cipher;
2724 addr->ourcert = tls_out.ourcert;
2725 addr->peercert = tls_out.peercert;
2726 addr->peerdn = tls_out.peerdn;
2727 addr->ocsp = tls_out.ocsp;
2728 addr->tlsver = tls_out.ver;
2729 }
2730 }
2731 }
2732
2733 /* if smtps, we'll have smtp_command set to something else; always safe to
2734 reset it here. */
2735 smtp_command = big_buffer;
2736
2737 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2738 helo_data is null, we are dealing with a connection that was passed from
2739 another process, and so we won't have expanded helo_data above. We have to
2740 expand it here. $sending_ip_address and $sending_port are set up right at the
2741 start of the Exim process (in exim.c). */
2742
2743 if (tls_out.active.sock >= 0)
2744 {
2745 uschar * greeting_cmd;
2746
2747 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2748 {
2749 uschar *message = string_sprintf("failed to expand helo_data: %s",
2750 expand_string_message);
2751 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2752 yield = DEFER;
2753 goto SEND_QUIT;
2754 }
2755
2756 #ifndef DISABLE_PIPE_CONNECT
2757 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2758 We're unlikely to get the group sent and delivered before the server sends its
2759 banner, but it's still worth sending as a group.
2760 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2761 the reverse. */
2762
2763 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2764 {
2765 sx->peer_offered = sx->ehlo_resp.crypted_features;
2766 if ((sx->early_pipe_active =
2767 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2768 DEBUG(D_transport) debug_printf("Using cached crypted PIPE_CONNECT\n");
2769 }
2770 #endif
2771 #ifdef EXPERIMMENTAL_ESMTP_LIMITS
2772 /* As we are about to send another EHLO, forget any LIMITS received so far. */
2773 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom = 0;
2774 if ((sx->max_mail = sx->conn_args.tblock->connection_max_message) == 0) sx->max_mail = 999999;
2775 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
2776 sx->single_rcpt_domain = FALSE;
2777 #endif
2778
2779 /* For SMTPS we need to wait for the initial OK response. */
2780 if (sx->smtps)
2781 #ifndef DISABLE_PIPE_CONNECT
2782 if (sx->early_pipe_active)
2783 {
2784 sx->pending_BANNER = TRUE;
2785 sx->outblock.cmd_count = 1;
2786 }
2787 else
2788 #endif
2789 if (!smtp_reap_banner(sx))
2790 goto RESPONSE_FAILED;
2791
2792 if (sx->lmtp)
2793 greeting_cmd = US"LHLO";
2794 else if (sx->esmtp)
2795 greeting_cmd = US"EHLO";
2796 else
2797 {
2798 greeting_cmd = US"HELO";
2799 DEBUG(D_transport)
2800 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2801 }
2802
2803 if (smtp_write_command(sx,
2804 #ifndef DISABLE_PIPE_CONNECT
2805 sx->early_pipe_active ? SCMD_BUFFER :
2806 #endif
2807 SCMD_FLUSH,
2808 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2809 goto SEND_FAILED;
2810
2811 #ifndef DISABLE_PIPE_CONNECT
2812 if (sx->early_pipe_active)
2813 sx->pending_EHLO = TRUE;
2814 else
2815 #endif
2816 {
2817 if (!smtp_reap_ehlo(sx))
2818 #ifdef USE_GNUTLS
2819 {
2820 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2821 cert late, under TLS1.3 - which means here; the first time we try to
2822 receive crypted data. Treat it as if it was a connect-time failure.
2823 See also the early-pipe equivalent... which will be hard; every call
2824 to sync_responses will need to check the result.
2825 It would be nicer to have GnuTLS check the cert during the handshake.
2826 Can it do that, with all the flexibility we need? */
2827
2828 tls_errstr = US"error on first read";
2829 goto TLS_CONN_FAILED;
2830 }
2831 #else
2832 goto RESPONSE_FAILED;
2833 #endif
2834 smtp_peer_options = 0;
2835 }
2836 }
2837
2838 /* If the host is required to use a secure channel, ensure that we
2839 have one. */
2840
2841 else if ( sx->smtps
2842 # ifdef SUPPORT_DANE
2843 || sx->conn_args.dane
2844 # endif
2845 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2846 )
2847 {
2848 errno = ERRNO_TLSREQUIRED;
2849 message = string_sprintf("a TLS session is required, but %s",
2850 smtp_peer_options & OPTION_TLS
2851 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2852 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2853 if (sx->conn_args.dane)
2854 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2855 smtp_peer_options & OPTION_TLS
2856 ? US"validation-failure" /* could do with better detail */
2857 : US"starttls-not-supported");
2858 # endif
2859 goto TLS_FAILED;
2860 }
2861 #endif /*DISABLE_TLS*/
2862
2863 /* If TLS is active, we have just started it up and re-done the EHLO command,
2864 so its response needs to be analyzed. If TLS is not active and this is a
2865 continued session down a previously-used socket, we haven't just done EHLO, so
2866 we skip this. */
2867
2868 if ( !continue_hostname
2869 #ifndef DISABLE_TLS
2870 || tls_out.active.sock >= 0
2871 #endif
2872 )
2873 {
2874 if (sx->esmtp || sx->lmtp)
2875 {
2876 #ifndef DISABLE_PIPE_CONNECT
2877 if (!sx->early_pipe_active)
2878 #endif
2879 {
2880 sx->peer_offered = ehlo_response(sx->buffer,
2881 0 /* no TLS */
2882 #ifndef DISABLE_PIPE_CONNECT
2883 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2884 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2885 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2886 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2887
2888 #else
2889
2890 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2891 | OPTION_CHUNKING
2892 | OPTION_PRDR
2893 # ifdef SUPPORT_I18N
2894 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2895 /*XXX if we hand peercaps on to continued-conn processes,
2896 must not depend on this addr */
2897 # endif
2898 | OPTION_DSN
2899 | OPTION_PIPE
2900 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2901 #endif
2902 );
2903 #ifndef DISABLE_PIPE_CONNECT
2904 if (tls_out.active.sock >= 0)
2905 sx->ehlo_resp.crypted_features = sx->peer_offered;
2906 #endif
2907
2908 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2909 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2910 {
2911 ehlo_response_limits_read(sx);
2912 ehlo_response_limits_apply(sx);
2913 }
2914 #endif
2915 }
2916
2917 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2918 lmtp_ignore_quota option was set. */
2919
2920 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2921
2922 /* If the response to EHLO specified support for the SIZE parameter, note
2923 this, provided size_addition is non-negative. */
2924
2925 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2926
2927 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2928 the current host, esmtp will be false, so PIPELINING can never be used. If
2929 the current host matches hosts_avoid_pipelining, don't do it. */
2930
2931 if ( sx->peer_offered & OPTION_PIPE
2932 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2933 smtp_peer_options |= OPTION_PIPE;
2934
2935 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2936 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2937
2938 if ( sx->peer_offered & OPTION_CHUNKING
2939 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) != OK)
2940 sx->peer_offered &= ~OPTION_CHUNKING;
2941
2942 if (sx->peer_offered & OPTION_CHUNKING)
2943 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2944
2945 #ifndef DISABLE_PRDR
2946 if ( sx->peer_offered & OPTION_PRDR
2947 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) != OK)
2948 sx->peer_offered &= ~OPTION_PRDR;
2949
2950 if (sx->peer_offered & OPTION_PRDR)
2951 DEBUG(D_transport) debug_printf("PRDR usable\n");
2952 #endif
2953
2954 /* Note if the server supports DSN */
2955 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2956 DEBUG(D_transport) debug_printf("%susing DSN\n",
2957 sx->peer_offered & OPTION_DSN ? "" : "not ");
2958
2959 #ifndef DISABLE_PIPE_CONNECT
2960 if ( sx->early_pipe_ok
2961 && !sx->early_pipe_active
2962 && tls_out.active.sock >= 0
2963 && smtp_peer_options & OPTION_PIPE
2964 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
2965 & OPTION_EARLY_PIPE)
2966 {
2967 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2968 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
2969 write_ehlo_cache_entry(sx);
2970 }
2971 #endif
2972
2973 /* Note if the response to EHLO specifies support for the AUTH extension.
2974 If it has, check that this host is one we want to authenticate to, and do
2975 the business. The host name and address must be available when the
2976 authenticator's client driver is running. */
2977
2978 switch (yield = smtp_auth(sx))
2979 {
2980 default: goto SEND_QUIT;
2981 case OK: break;
2982 case FAIL_SEND: goto SEND_FAILED;
2983 case FAIL: goto RESPONSE_FAILED;
2984 }
2985 }
2986 }
2987 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2988
2989 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2990 message-specific. */
2991
2992 sx->setting_up = FALSE;
2993
2994 #ifdef SUPPORT_I18N
2995 if (sx->addrlist->prop.utf8_msg)
2996 {
2997 uschar * s;
2998
2999 /* If the transport sets a downconversion mode it overrides any set by ACL
3000 for the message. */
3001
3002 if ((s = ob->utf8_downconvert))
3003 {
3004 if (!(s = expand_string(s)))
3005 {
3006 message = string_sprintf("failed to expand utf8_downconvert: %s",
3007 expand_string_message);
3008 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
3009 yield = DEFER;
3010 goto SEND_QUIT;
3011 }
3012 switch (*s)
3013 {
3014 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
3015 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3016 break;
3017 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
3018 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3019 break;
3020 case '-': if (s[1] == '1')
3021 {
3022 sx->addrlist->prop.utf8_downcvt = FALSE;
3023 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
3024 }
3025 break;
3026 }
3027 }
3028
3029 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
3030 && !sx->addrlist->prop.utf8_downcvt_maybe;
3031 DEBUG(D_transport) if (!sx->utf8_needed)
3032 debug_printf("utf8: %s downconvert\n",
3033 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
3034 }
3035
3036 /* If this is an international message we need the host to speak SMTPUTF8 */
3037 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
3038 {
3039 errno = ERRNO_UTF8_FWD;
3040 goto RESPONSE_FAILED;
3041 }
3042 #endif /*SUPPORT_I18N*/
3043
3044 return OK;
3045
3046
3047 {
3048 int code;
3049
3050 RESPONSE_FAILED:
3051 if (errno == ECONNREFUSED) /* first-read error on a TFO conn */
3052 {
3053 /* There is a testing facility for simulating a connection timeout, as I
3054 can't think of any other way of doing this. It converts a connection
3055 refused into a timeout if the timeout is set to 999999. This is done for
3056 a 3whs connection in ip_connect(), but a TFO connection does not error
3057 there - instead it gets ECONNREFUSED on the first data read. Tracking
3058 that a TFO really was done is too hard, or we would set a
3059 sx->pending_conn_done bit and test that in smtp_reap_banner() and
3060 smtp_reap_ehlo(). That would let us also add the conn-timeout to the
3061 cmd-timeout. */
3062
3063 if (f.running_in_test_harness && ob->connect_timeout == 999999)
3064 errno = ETIMEDOUT;
3065 set_errno_nohost(sx->addrlist,
3066 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
3067 sx->verify ? US strerror(errno) : NULL,
3068 DEFER, FALSE, &sx->delivery_start);
3069 sx->send_quit = FALSE;
3070 return DEFER;
3071 }
3072
3073 /* really an error on an SMTP read */
3074 message = NULL;
3075 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
3076 sx->buffer, &code, &message, &pass_message);
3077 yield = DEFER;
3078 goto FAILED;
3079
3080 SEND_FAILED:
3081 code = '4';
3082 message = US string_sprintf("send() to %s [%s] failed: %s",
3083 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
3084 sx->send_quit = FALSE;
3085 yield = DEFER;
3086 goto FAILED;
3087
3088 EHLOHELO_FAILED:
3089 code = '4';
3090 message = string_sprintf("Remote host closed connection in response to %s"
3091 " (EHLO response was: %s)", smtp_command, sx->buffer);
3092 sx->send_quit = FALSE;
3093 yield = DEFER;
3094 goto FAILED;
3095
3096 /* This label is jumped to directly when a TLS negotiation has failed,
3097 or was not done for a host for which it is required. Values will be set
3098 in message and errno, and setting_up will always be true. Treat as
3099 a temporary error. */
3100
3101 #ifndef DISABLE_TLS
3102 TLS_FAILED:
3103 code = '4', yield = DEFER;
3104 goto FAILED;
3105 #endif
3106
3107 /* The failure happened while setting up the call; see if the failure was
3108 a 5xx response (this will either be on connection, or following HELO - a 5xx
3109 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
3110 fail all addresses, as this host is never going to accept them. For other
3111 errors during setting up (timeouts or whatever), defer all addresses, and
3112 yield DEFER, so that the host is not tried again for a while.
3113
3114 XXX This peeking for another host feels like a layering violation. We want
3115 to note the host as unusable, but down here we shouldn't know if this was
3116 the last host to try for the addr(list). Perhaps the upper layer should be
3117 the one to do set_errno() ? The problem is that currently the addr is where
3118 errno etc. are stashed, but until we run out of hosts to try the errors are
3119 host-specific. Maybe we should enhance the host_item definition? */
3120
3121 FAILED:
3122 sx->ok = FALSE; /* For when reached by GOTO */
3123 set_errno(sx->addrlist, errno, message,
3124 sx->conn_args.host->next
3125 ? DEFER
3126 : code == '5'
3127 #ifdef SUPPORT_I18N
3128 || errno == ERRNO_UTF8_FWD
3129 #endif
3130 ? FAIL : DEFER,
3131 pass_message,
3132 errno == ECONNREFUSED ? NULL : sx->conn_args.host,
3133 #ifdef EXPERIMENTAL_DSN_INFO
3134 sx->smtp_greeting, sx->helo_response,
3135 #endif
3136 &sx->delivery_start);
3137 }
3138
3139
3140 SEND_QUIT:
3141
3142 if (sx->send_quit)
3143 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
3144
3145 #ifndef DISABLE_TLS
3146 if (sx->cctx.tls_ctx)
3147 {
3148 if (sx->send_tlsclose)
3149 {
3150 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
3151 sx->send_tlsclose = FALSE;
3152 }
3153 sx->cctx.tls_ctx = NULL;
3154 }
3155 #endif
3156
3157 /* Close the socket, and return the appropriate value, first setting
3158 works because the NULL setting is passed back to the calling process, and
3159 remote_max_parallel is forced to 1 when delivering over an existing connection,
3160 */
3161
3162 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3163 if (sx->send_quit)
3164 {
3165 shutdown(sx->cctx.sock, SHUT_WR);
3166 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
3167 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
3168 i--; /* drain socket */
3169 sx->send_quit = FALSE;
3170 }
3171 (void)close(sx->cctx.sock);
3172 sx->cctx.sock = -1;
3173
3174 #ifndef DISABLE_EVENT
3175 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL);
3176 #endif
3177
3178 continue_transport = NULL;
3179 continue_hostname = NULL;
3180 return yield;
3181 }
3182
3183
3184
3185
3186 /* Create the string of options that will be appended to the MAIL FROM:
3187 in the connection context buffer */
3188
3189 static int
build_mailcmd_options(smtp_context * sx,address_item * addrlist)3190 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
3191 {
3192 uschar * p = sx->buffer;
3193 address_item * addr;
3194 int address_count;
3195
3196 *p = 0;
3197
3198 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
3199 send it, adding something to the message size to allow for imprecision
3200 and things that get added en route. Exim keeps the number of lines
3201 in a message, so we can give an accurate value for the original message, but we
3202 need some additional to handle added headers. (Double "." characters don't get
3203 included in the count.) */
3204
3205 if ( message_size > 0
3206 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
3207 {
3208 /*XXX problem here under spool_files_wireformat?
3209 Or just forget about lines? Or inflate by a fixed proportion? */
3210
3211 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
3212 while (*p) p++;
3213 }
3214
3215 #ifndef DISABLE_PRDR
3216 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
3217 request that */
3218
3219 sx->prdr_active = FALSE;
3220 if (sx->peer_offered & OPTION_PRDR)
3221 for (address_item * addr = addrlist; addr; addr = addr->next)
3222 if (addr->transport_return == PENDING_DEFER)
3223 {
3224 for (addr = addr->next; addr; addr = addr->next)
3225 if (addr->transport_return == PENDING_DEFER)
3226 { /* at least two recipients to send */
3227 sx->prdr_active = TRUE;
3228 sprintf(CS p, " PRDR"); p += 5;
3229 break;
3230 }
3231 break;
3232 }
3233 #endif
3234
3235 #ifdef SUPPORT_I18N
3236 /* If it supports internationalised messages, and this meesage need that,
3237 request it */
3238
3239 if ( sx->peer_offered & OPTION_UTF8
3240 && addrlist->prop.utf8_msg
3241 && !addrlist->prop.utf8_downcvt
3242 )
3243 Ustrcpy(p, US" SMTPUTF8"), p += 9;
3244 #endif
3245
3246 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3247 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3248 addr && address_count < sx->max_rcpt; /*XXX maybe also || sx->single_rcpt_domain ? */
3249 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3250 {
3251 address_count++;
3252 if (!(addr->dsn_flags & rf_dsnlasthop))
3253 {
3254 sx->dsn_all_lasthop = FALSE;
3255 break;
3256 }
3257 }
3258
3259 /* Add any DSN flags to the mail command */
3260
3261 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3262 {
3263 if (dsn_ret == dsn_ret_hdrs)
3264 { Ustrcpy(p, US" RET=HDRS"); p += 9; }
3265 else if (dsn_ret == dsn_ret_full)
3266 { Ustrcpy(p, US" RET=FULL"); p += 9; }
3267
3268 if (dsn_envid)
3269 {
3270 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3271 while (*p) p++;
3272 }
3273 }
3274
3275 /* If an authenticated_sender override has been specified for this transport
3276 instance, expand it. If the expansion is forced to fail, and there was already
3277 an authenticated_sender for this message, the original value will be used.
3278 Other expansion failures are serious. An empty result is ignored, but there is
3279 otherwise no check - this feature is expected to be used with LMTP and other
3280 cases where non-standard addresses (e.g. without domains) might be required. */
3281
3282 return smtp_mail_auth_str(sx, p, addrlist) ? ERROR : OK;
3283 }
3284
3285
3286 static void
build_rcptcmd_options(smtp_context * sx,const address_item * addr)3287 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3288 {
3289 uschar * p = sx->buffer;
3290 *p = 0;
3291
3292 /* Add any DSN flags to the rcpt command */
3293
3294 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3295 {
3296 if (addr->dsn_flags & rf_dsnflags)
3297 {
3298 BOOL first = TRUE;
3299
3300 Ustrcpy(p, US" NOTIFY=");
3301 while (*p) p++;
3302 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3303 {
3304 if (!first) *p++ = ',';
3305 first = FALSE;
3306 Ustrcpy(p, rf_names[i]);
3307 while (*p) p++;
3308 }
3309 }
3310
3311 if (addr->dsn_orcpt)
3312 {
3313 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3314 addr->dsn_orcpt);
3315 while (*p) p++;
3316 }
3317 }
3318 }
3319
3320
3321
3322 /*
3323 Return:
3324 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3325 -1 MAIL response error
3326 -2 any non-MAIL read i/o error
3327 -3 non-MAIL response timeout
3328 -4 internal error; channel still usable
3329 -5 transmit failed
3330 */
3331
3332 int
smtp_write_mail_and_rcpt_cmds(smtp_context * sx,int * yield)3333 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3334 {
3335 address_item * addr;
3336 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3337 address_item * restart_addr = NULL;
3338 #endif
3339 int address_count, pipe_limit;
3340 int rc;
3341
3342 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3343 {
3344 *yield = ERROR;
3345 return -4;
3346 }
3347
3348 /* From here until we send the DATA command, we can make use of PIPELINING
3349 if the server host supports it. The code has to be able to check the responses
3350 at any point, for when the buffer fills up, so we write it totally generally.
3351 When PIPELINING is off, each command written reports that it has flushed the
3352 buffer. */
3353
3354 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3355
3356 {
3357 uschar * s = sx->from_addr;
3358 #ifdef SUPPORT_I18N
3359 uschar * errstr = NULL;
3360
3361 /* If we must downconvert, do the from-address here. Remember we had to
3362 for the to-addresses (done below), and also (ugly) for re-doing when building
3363 the delivery log line. */
3364
3365 if ( sx->addrlist->prop.utf8_msg
3366 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3367 )
3368 {
3369 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3370 {
3371 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, &sx->delivery_start);
3372 *yield = ERROR;
3373 return -4;
3374 }
3375 setflag(sx->addrlist, af_utf8_downcvt);
3376 }
3377 #endif
3378
3379 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3380 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3381 }
3382
3383 mail_command = string_copy(big_buffer); /* Save for later error message */
3384
3385 switch(rc)
3386 {
3387 case -1: /* Transmission error */
3388 return -5;
3389
3390 case +1: /* Cmd was sent */
3391 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3392 (SOB sx->conn_args.ob)->command_timeout))
3393 {
3394 if (errno == 0 && sx->buffer[0] == '4')
3395 {
3396 errno = ERRNO_MAIL4XX;
3397 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3398 }
3399 return -1;
3400 }
3401 sx->pending_MAIL = FALSE;
3402 break;
3403
3404 /* otherwise zero: command queued for pipeline */
3405 }
3406
3407 /* Pass over all the relevant recipient addresses for this host, which are the
3408 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3409 several before we have to read the responses for those seen so far. This
3410 checking is done by a subroutine because it also needs to be done at the end.
3411 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3412 the next one if not all are sent.
3413
3414 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3415 last address because we want to abort if any recipients have any kind of
3416 problem, temporary or permanent. We know that all recipient addresses will have
3417 the PENDING_DEFER status, because only one attempt is ever made, and we know
3418 that max_rcpt will be large, so all addresses will be done at once.
3419
3420 For verify we flush the pipeline after any (the only) rcpt address. */
3421
3422 for (addr = sx->first_addr, address_count = 0, pipe_limit = 100;
3423 addr && address_count < sx->max_rcpt;
3424 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3425 {
3426 int cmds_sent;
3427 BOOL no_flush;
3428 uschar * rcpt_addr;
3429
3430 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3431 if ( sx->single_rcpt_domain /* restriction on domains */
3432 && address_count > 0 /* not first being sent */
3433 && Ustrcmp(addr->domain, sx->first_addr->domain) != 0 /* dom diff from first */
3434 )
3435 {
3436 DEBUG(D_transport) debug_printf("skipping different domain %s\n", addr->domain);
3437
3438 /* Ensure the smtp-response reaper does not think the address had a RCPT
3439 command sent for it. Reset to PENDING_DEFER in smtp_deliver(), where we
3440 goto SEND_MESSAGE. */
3441
3442 addr->transport_return = SKIP;
3443 if (!restart_addr) restart_addr = addr; /* note restart point */
3444 continue; /* skip this one */
3445 }
3446 #endif
3447
3448 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3449 ? dsn_support_yes : dsn_support_no;
3450
3451 address_count++;
3452 if (pipe_limit-- <= 0)
3453 { no_flush = FALSE; pipe_limit = 100; }
3454 else
3455 no_flush = pipelining_active && !sx->verify
3456 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3457
3458 build_rcptcmd_options(sx, addr);
3459
3460 /* Now send the RCPT command, and process outstanding responses when
3461 necessary. After a timeout on RCPT, we just end the function, leaving the
3462 yield as OK, because this error can often mean that there is a problem with
3463 just one address, so we don't want to delay the host. */
3464
3465 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3466
3467 #ifdef SUPPORT_I18N
3468 if ( testflag(sx->addrlist, af_utf8_downcvt)
3469 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3470 )
3471 {
3472 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3473 errno = ERRNO_EXPANDFAIL;
3474 return -5; /*XXX too harsh? */
3475 }
3476 #endif
3477
3478 cmds_sent = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3479 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3480
3481 if (cmds_sent < 0) return -5;
3482 if (cmds_sent > 0)
3483 {
3484 switch(sync_responses(sx, cmds_sent, 0))
3485 {
3486 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3487 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3488 break;
3489
3490 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3491 if (!sx->lmtp) /* can't tell about progress yet */
3492 sx->completed_addr = TRUE;
3493 case 0: /* No 2xx or 5xx, but no probs */
3494 /* If any RCPT got a 452 response then next_addr has been updated
3495 for restarting with a new MAIL on the same connection. Send no more
3496 RCPTs for this MAIL. */
3497
3498 if (sx->RCPT_452)
3499 {
3500 DEBUG(D_transport) debug_printf("seen 452 too-many-rcpts\n");
3501 sx->RCPT_452 = FALSE;
3502 /* sx->next_addr has been reset for fast_retry */
3503 return 0;
3504 }
3505 break;
3506
3507 case -1: return -3; /* Timeout on RCPT */
3508 case -2: return -2; /* non-MAIL read i/o error */
3509 default: return -1; /* any MAIL error */
3510
3511 #ifndef DISABLE_PIPE_CONNECT
3512 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3513 case -5: return -1; /* TLS first-read error */
3514 #endif
3515 }
3516 }
3517 } /* Loop for next address */
3518
3519 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3520 sx->next_addr = restart_addr ? restart_addr : addr;
3521 #else
3522 sx->next_addr = addr;
3523 #endif
3524 return 0;
3525 }
3526
3527
3528 #ifndef DISABLE_TLS
3529 /*****************************************************
3530 * Proxy TLS connection for another transport process *
3531 ******************************************************/
3532 /*
3533 Close the unused end of the pipe, fork once more, then use the given buffer
3534 as a staging area, and select on both the given fd and the TLS'd client-fd for
3535 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3536 Do blocking full-size writes, and reads under a timeout. Once both input
3537 channels are closed, exit the process.
3538
3539 Arguments:
3540 ct_ctx tls context
3541 buf space to use for buffering
3542 bufsiz size of buffer
3543 pfd pipe filedescriptor array; [0] is comms to proxied process
3544 timeout per-read timeout, seconds
3545
3546 Does not return.
3547 */
3548
3549 void
smtp_proxy_tls(void * ct_ctx,uschar * buf,size_t bsize,int * pfd,int timeout)3550 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3551 int timeout)
3552 {
3553 struct pollfd p[2] = {{.fd = tls_out.active.sock, .events = POLLIN},
3554 {.fd = pfd[0], .events = POLLIN}};
3555 int rc, i;
3556 BOOL send_tls_shutdown = TRUE;
3557
3558 close(pfd[1]);
3559 if ((rc = exim_fork(US"tls-proxy")))
3560 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3561
3562 set_process_info("proxying TLS connection for continued transport");
3563
3564 do
3565 {
3566 time_t time_left = timeout;
3567 time_t time_start = time(NULL);
3568
3569 /* wait for data */
3570 do
3571 {
3572 rc = poll(p, 2, time_left * 1000);
3573
3574 if (rc < 0 && errno == EINTR)
3575 if ((time_left -= time(NULL) - time_start) > 0) continue;
3576
3577 if (rc <= 0)
3578 {
3579 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3580 goto done;
3581 }
3582
3583 /* For errors where not readable, bomb out */
3584
3585 if (p[0].revents & POLLERR || p[1].revents & POLLERR)
3586 {
3587 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3588 p[0].revents & POLLERR ? "tls" : "proxy");
3589 if (!(p[0].revents & POLLIN || p[1].events & POLLIN))
3590 goto done;
3591 DEBUG(D_transport) debug_printf("- but also readable; no exit yet\n");
3592 }
3593 }
3594 while (rc < 0 || !(p[0].revents & POLLIN || p[1].revents & POLLIN));
3595
3596 /* handle inbound data */
3597 if (p[0].revents & POLLIN)
3598 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0) /* Expect -1 for EOF; */
3599 { /* that reaps the TLS Close Notify record */
3600 p[0].fd = -1;
3601 shutdown(pfd[0], SHUT_WR);
3602 timeout = 5;
3603 }
3604 else
3605 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3606 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3607
3608 /* Handle outbound data. We cannot combine payload and the TLS-close
3609 due to the limitations of the (pipe) channel feeding us. Maybe use a unix-domain
3610 socket? */
3611 if (p[1].revents & POLLIN)
3612 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3613 {
3614 p[1].fd = -1;
3615
3616 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
3617 (void) setsockopt(tls_out.active.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
3618 # endif
3619 tls_shutdown_wr(ct_ctx);
3620 send_tls_shutdown = FALSE;
3621 shutdown(tls_out.active.sock, SHUT_WR);
3622 }
3623 else
3624 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3625 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3626 goto done;
3627 }
3628 while (p[0].fd >= 0 || p[1].fd >= 0);
3629
3630 done:
3631 if (send_tls_shutdown) tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3632 ct_ctx = NULL;
3633 testharness_pause_ms(100); /* let logging complete */
3634 exim_exit(EXIT_SUCCESS);
3635 }
3636 #endif
3637
3638
3639 /*************************************************
3640 * Deliver address list to given host *
3641 *************************************************/
3642
3643 /* If continue_hostname is not null, we get here only when continuing to
3644 deliver down an existing channel. The channel was passed as the standard
3645 input. TLS is never active on a passed channel; the previous process either
3646 closes it down before passing the connection on, or inserts a TLS-proxy
3647 process and passes on a cleartext conection.
3648
3649 Otherwise, we have to make a connection to the remote host, and do the
3650 initial protocol exchange.
3651
3652 When running as an MUA wrapper, if the sender or any recipient is rejected,
3653 temporarily or permanently, we force failure for all recipients.
3654
3655 Arguments:
3656 addrlist chain of potential addresses to deliver; only those whose
3657 transport_return field is set to PENDING_DEFER are currently
3658 being processed; others should be skipped - they have either
3659 been delivered to an earlier host or IP address, or been
3660 failed by one of them.
3661 host host to deliver to
3662 host_af AF_INET or AF_INET6
3663 defport default TCP/IP port to use if host does not specify, in host
3664 byte order
3665 interface interface to bind to, or NULL
3666 tblock transport instance block
3667 message_defer set TRUE if yield is OK, but all addresses were deferred
3668 because of a non-recipient, non-host failure, that is, a
3669 4xx response to MAIL FROM, DATA, or ".". This is a defer
3670 that is specific to the message.
3671 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3672 a second attempt after TLS initialization fails
3673
3674 Returns: OK - the connection was made and the delivery attempted;
3675 the result for each address is in its data block.
3676 DEFER - the connection could not be made, or something failed
3677 while setting up the SMTP session, or there was a
3678 non-message-specific error, such as a timeout.
3679 ERROR - a filter command is specified for this transport,
3680 and there was a problem setting it up; OR helo_data
3681 or add_headers or authenticated_sender is specified
3682 for this transport, and the string failed to expand
3683
3684 For all non-OK returns the first addr of the list carries the
3685 time taken for the attempt.
3686 */
3687
3688 static int
smtp_deliver(address_item * addrlist,host_item * host,int host_af,int defport,uschar * interface,transport_instance * tblock,BOOL * message_defer,BOOL suppress_tls)3689 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3690 uschar *interface, transport_instance *tblock,
3691 BOOL *message_defer, BOOL suppress_tls)
3692 {
3693 smtp_transport_options_block * ob = SOB tblock->options_block;
3694 int yield = OK;
3695 int save_errno;
3696 int rc;
3697
3698 uschar *message = NULL;
3699 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3700 smtp_context * sx = store_get(sizeof(*sx), TRUE); /* tainted, for the data buffers */
3701 BOOL pass_message = FALSE;
3702 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3703 BOOL mail_limit = FALSE;
3704 #endif
3705 #ifdef SUPPORT_DANE
3706 BOOL dane_held;
3707 #endif
3708 BOOL tcw_done = FALSE, tcw = FALSE;
3709
3710 *message_defer = FALSE;
3711
3712 memset(sx, 0, sizeof(*sx));
3713 sx->addrlist = addrlist;
3714 sx->conn_args.host = host;
3715 sx->conn_args.host_af = host_af,
3716 sx->port = defport;
3717 sx->conn_args.interface = interface;
3718 sx->helo_data = NULL;
3719 sx->conn_args.tblock = tblock;
3720 /* sx->verify = FALSE; */
3721 gettimeofday(&sx->delivery_start, NULL);
3722 sx->sync_addr = sx->first_addr = addrlist;
3723
3724 REPEAT_CONN:
3725 #ifdef SUPPORT_DANE
3726 dane_held = FALSE;
3727 #endif
3728
3729 /* Get the channel set up ready for a message, MAIL FROM being the next
3730 SMTP command to send. */
3731
3732 if ((rc = smtp_setup_conn(sx, suppress_tls)) != OK)
3733 {
3734 timesince(&addrlist->delivery_time, &sx->delivery_start);
3735 yield = rc;
3736 goto TIDYUP;
3737 }
3738
3739 #ifdef SUPPORT_DANE
3740 /* If the connection used DANE, ignore for now any addresses with incompatible
3741 domains. The SNI has to be the domain. Arrange a whole new TCP conn later,
3742 just in case only TLS isn't enough. */
3743
3744 if (sx->conn_args.dane)
3745 {
3746 const uschar * dane_domain = sx->first_addr->domain;
3747
3748 for (address_item * a = sx->first_addr->next; a; a = a->next)
3749 if ( a->transport_return == PENDING_DEFER
3750 && Ustrcmp(dane_domain, a->domain) != 0)
3751 {
3752 DEBUG(D_transport) debug_printf("DANE: holding %s for later\n", a->domain);
3753 dane_held = TRUE;
3754 a->transport_return = DANE;
3755 }
3756 }
3757 #endif
3758
3759 /* If there is a filter command specified for this transport, we can now
3760 set it up. This cannot be done until the identity of the host is known. */
3761
3762 if (tblock->filter_command)
3763 {
3764 transport_filter_timeout = tblock->filter_timeout;
3765
3766 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3767 yield ERROR. */
3768
3769 if (!transport_set_up_command(&transport_filter_argv,
3770 tblock->filter_command, TRUE, DEFER, addrlist,
3771 string_sprintf("%.50s transport", tblock->name), NULL))
3772 {
3773 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3774 FALSE, &sx->delivery_start);
3775 yield = ERROR;
3776 goto SEND_QUIT;
3777 }
3778
3779 if ( transport_filter_argv
3780 && *transport_filter_argv
3781 && **transport_filter_argv
3782 && sx->peer_offered & OPTION_CHUNKING
3783 #ifndef DISABLE_DKIM
3784 /* When dkim signing, chunking is handled even with a transport-filter */
3785 && !(ob->dkim.dkim_private_key && ob->dkim.dkim_domain && ob->dkim.dkim_selector)
3786 && !ob->dkim.force_bodyhash
3787 #endif
3788 )
3789 {
3790 sx->peer_offered &= ~OPTION_CHUNKING;
3791 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3792 }
3793 }
3794
3795 /* For messages that have more than the maximum number of envelope recipients,
3796 we want to send several transactions down the same SMTP connection. (See
3797 comments in deliver.c as to how this reconciles, heuristically, with
3798 remote_max_parallel.) This optimization was added to Exim after the following
3799 code was already working. The simplest way to put it in without disturbing the
3800 code was to use a goto to jump back to this point when there is another
3801 transaction to handle. */
3802
3803 SEND_MESSAGE:
3804 sx->from_addr = return_path;
3805 sx->sync_addr = sx->first_addr;
3806 sx->ok = FALSE;
3807 sx->send_rset = TRUE;
3808 sx->completed_addr = FALSE;
3809
3810
3811 /* If we are a continued-connection-after-verify the MAIL and RCPT
3812 commands were already sent; do not re-send but do mark the addrs as
3813 having been accepted up to RCPT stage. A traditional cont-conn
3814 always has a sequence number greater than one. */
3815
3816 if (continue_hostname && continue_sequence == 1)
3817 {
3818 /* sx->pending_MAIL = FALSE; */
3819 sx->ok = TRUE;
3820 /* sx->next_addr = NULL; */
3821
3822 for (address_item * addr = addrlist; addr; addr = addr->next)
3823 addr->transport_return = PENDING_OK;
3824 }
3825 else
3826 {
3827 /* Initiate a message transfer. */
3828
3829 switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))
3830 {
3831 case 0: break;
3832 case -1: case -2: goto RESPONSE_FAILED;
3833 case -3: goto END_OFF;
3834 case -4: goto SEND_QUIT;
3835 default: goto SEND_FAILED;
3836 }
3837
3838 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3839 permanently or temporarily. We should have flushed and synced after the last
3840 RCPT. */
3841
3842 if (mua_wrapper)
3843 {
3844 address_item * a;
3845 unsigned cnt;
3846
3847 for (a = sx->first_addr, cnt = 0; a && cnt < sx->max_rcpt; a = a->next, cnt++)
3848 if (a->transport_return != PENDING_OK)
3849 {
3850 /*XXX could we find a better errno than 0 here? */
3851 set_errno_nohost(addrlist, 0, a->message, FAIL,
3852 testflag(a, af_pass_message), &sx->delivery_start);
3853 sx->ok = FALSE;
3854 break;
3855 }
3856 }
3857 }
3858
3859 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3860 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3861 have a good recipient buffered up if we are pipelining. We don't want to waste
3862 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3863 are pipelining. The responses are all handled by sync_responses().
3864 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3865 to send is. */
3866
3867 if ( !(sx->peer_offered & OPTION_CHUNKING)
3868 && (sx->ok || (pipelining_active && !mua_wrapper)))
3869 {
3870 int count = smtp_write_command(sx, SCMD_FLUSH, "DATA\r\n");
3871
3872 if (count < 0) goto SEND_FAILED;
3873 switch(sync_responses(sx, count, sx->ok ? +1 : -1))
3874 {
3875 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3876 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3877 break;
3878
3879 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3880 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
3881 case 0: break; /* No 2xx or 5xx, but no probs */
3882
3883 case -1: goto END_OFF; /* Timeout on RCPT */
3884
3885 #ifndef DISABLE_PIPE_CONNECT
3886 case -5: /* TLS first-read error */
3887 case -4: HDEBUG(D_transport)
3888 debug_printf("failed reaping pipelined cmd responses\n");
3889 #endif
3890 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3891 }
3892 pipelining_active = FALSE;
3893 data_command = string_copy(big_buffer); /* Save for later error message */
3894 }
3895
3896 /* If there were no good recipients (but otherwise there have been no
3897 problems), just set ok TRUE, since we have handled address-specific errors
3898 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3899 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3900 well as body. Set the appropriate timeout value to be used for each chunk.
3901 (Haven't been able to make it work using select() for writing yet.) */
3902
3903 if ( !sx->ok
3904 && (!(sx->peer_offered & OPTION_CHUNKING) || !pipelining_active))
3905 {
3906 /* Save the first address of the next batch. */
3907 sx->first_addr = sx->next_addr;
3908
3909 sx->ok = TRUE;
3910 }
3911 else
3912 {
3913 transport_ctx tctx = {
3914 .u = {.fd = sx->cctx.sock}, /*XXX will this need TLS info? */
3915 .tblock = tblock,
3916 .addr = addrlist,
3917 .check_string = US".",
3918 .escape_string = US"..", /* Escaping strings */
3919 .options =
3920 topt_use_crlf | topt_escape_headers
3921 | (tblock->body_only ? topt_no_headers : 0)
3922 | (tblock->headers_only ? topt_no_body : 0)
3923 | (tblock->return_path_add ? topt_add_return_path : 0)
3924 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3925 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3926 };
3927
3928 /* If using CHUNKING we need a callback from the generic transport
3929 support to us, for the sending of BDAT smtp commands and the reaping
3930 of responses. The callback needs a whole bunch of state so set up
3931 a transport-context structure to be passed around. */
3932
3933 if (sx->peer_offered & OPTION_CHUNKING)
3934 {
3935 tctx.check_string = tctx.escape_string = NULL;
3936 tctx.options |= topt_use_bdat;
3937 tctx.chunk_cb = smtp_chunk_cmd_callback;
3938 sx->pending_BDAT = FALSE;
3939 sx->good_RCPT = sx->ok;
3940 sx->cmd_count = 0;
3941 tctx.smtp_context = sx;
3942 }
3943 else
3944 tctx.options |= topt_end_dot;
3945
3946 /* Save the first address of the next batch. */
3947 sx->first_addr = sx->next_addr;
3948
3949 /* Responses from CHUNKING commands go in buffer. Otherwise,
3950 there has not been a response. */
3951
3952 sx->buffer[0] = 0;
3953
3954 sigalrm_seen = FALSE;
3955 transport_write_timeout = ob->data_timeout;
3956 smtp_command = US"sending data block"; /* For error messages */
3957 DEBUG(D_transport|D_v)
3958 if (sx->peer_offered & OPTION_CHUNKING)
3959 debug_printf(" will write message using CHUNKING\n");
3960 else
3961 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3962 transport_count = 0;
3963
3964 #ifndef DISABLE_DKIM
3965 {
3966 # ifdef MEASURE_TIMING
3967 struct timeval t0;
3968 gettimeofday(&t0, NULL);
3969 # endif
3970 dkim_exim_sign_init();
3971 # ifdef EXPERIMENTAL_ARC
3972 {
3973 uschar * s = ob->arc_sign;
3974 if (s)
3975 {
3976 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
3977 {
3978 if (!f.expand_string_forcedfail)
3979 {
3980 message = US"failed to expand arc_sign";
3981 sx->ok = FALSE;
3982 goto SEND_FAILED;
3983 }
3984 }
3985 else if (*s)
3986 {
3987 /* Ask dkim code to hash the body for ARC */
3988 (void) arc_ams_setup_sign_bodyhash();
3989 ob->dkim.force_bodyhash = TRUE;
3990 }
3991 }
3992 }
3993 # endif
3994 # ifdef MEASURE_TIMING
3995 report_time_since(&t0, US"dkim_exim_sign_init (delta)");
3996 # endif
3997 }
3998 #endif
3999
4000 /* See if we can pipeline QUIT. Reasons not to are
4001 - pipelining not active
4002 - not ok to send quit
4003 - errors in amtp transation responses
4004 - more addrs to send for this message or this host
4005 - this message was being retried
4006 - more messages for this host
4007 If we can, we want the message-write to not flush (the tail end of) its data out. */
4008
4009 if ( sx->pipelining_used
4010 && (sx->ok && sx->completed_addr || sx->peer_offered & OPTION_CHUNKING)
4011 && sx->send_quit
4012 && !(sx->first_addr || f.continue_more)
4013 && f.deliver_firsttime
4014 )
4015 {
4016 smtp_compare_t t_compare =
4017 {.tblock = tblock, .current_sender_address = sender_address};
4018
4019 tcw_done = TRUE;
4020 tcw =
4021 #ifndef DISABLE_TLS
4022 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4023 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4024 )
4025 &&
4026 #endif
4027 transport_check_waiting(tblock->name, host->name,
4028 tblock->connection_max_messages, new_message_id,
4029 (oicf)smtp_are_same_identities, (void*)&t_compare);
4030 if (!tcw)
4031 {
4032 HDEBUG(D_transport) debug_printf("will pipeline QUIT\n");
4033 tctx.options |= topt_no_flush;
4034 }
4035 }
4036
4037 #ifndef DISABLE_DKIM
4038 sx->ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
4039 #else
4040 sx->ok = transport_write_message(&tctx, 0);
4041 #endif
4042
4043 /* transport_write_message() uses write() because it is called from other
4044 places to write to non-sockets. This means that under some OS (e.g. Solaris)
4045 it can exit with "Broken pipe" as its error. This really means that the
4046 socket got closed at the far end. */
4047
4048 transport_write_timeout = 0; /* for subsequent transports */
4049
4050 /* Failure can either be some kind of I/O disaster (including timeout),
4051 or the failure of a transport filter or the expansion of added headers.
4052 Or, when CHUNKING, it can be a protocol-detected failure. */
4053
4054 if (!sx->ok)
4055 if (message) goto SEND_FAILED;
4056 else goto RESPONSE_FAILED;
4057
4058 /* We used to send the terminating "." explicitly here, but because of
4059 buffering effects at both ends of TCP/IP connections, you don't gain
4060 anything by keeping it separate, so it might as well go in the final
4061 data buffer for efficiency. This is now done by setting the topt_end_dot
4062 flag above. */
4063
4064 smtp_command = US"end of data";
4065
4066 /* If we can pipeline a QUIT with the data them send it now. If a new message
4067 for this host appeared in the queue while data was being sent, we will not see
4068 it and it will have to wait for a queue run. If there was one but another
4069 thread took it, we might attempt to send it - but locking of spoolfiles will
4070 detect that. Use _MORE to get QUIT in FIN segment. */
4071
4072 if (tcw_done && !tcw)
4073 {
4074 /*XXX jgh 2021/03/10 google et. al screwup. G, at least, sends TCP FIN in response to TLS
4075 close-notify. Under TLS 1.3, violating RFC.
4076 However, TLS 1.2 does not have half-close semantics. */
4077
4078 if ( sx->cctx.tls_ctx
4079 #if 0 && !defined(DISABLE_TLS)
4080 && Ustrcmp(tls_out.ver, "TLS1.3") != 0
4081 #endif
4082 || !f.deliver_firsttime
4083 )
4084 { /* Send QUIT now and not later */
4085 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
4086 sx->send_quit = FALSE;
4087 }
4088 else
4089 { /* add QUIT to the output buffer */
4090 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4091 sx->send_quit = FALSE; /* avoid sending it later */
4092
4093 #ifndef DISABLE_TLS
4094 if (sx->cctx.tls_ctx) /* need to send TLS Close Notify */
4095 {
4096 # ifdef EXIM_TCP_CORK /* Use _CORK to get Close Notify in FIN segment */
4097 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4098 # endif
4099 tls_shutdown_wr(sx->cctx.tls_ctx);
4100 sx->send_tlsclose = FALSE; /* avoid later repeat */
4101 }
4102 #endif
4103 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4104 shutdown(sx->cctx.sock, SHUT_WR); /* flush output buffer, with TCP FIN */
4105 }
4106 }
4107
4108 if (sx->peer_offered & OPTION_CHUNKING && sx->cmd_count > 1)
4109 {
4110 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
4111 switch(sync_responses(sx, sx->cmd_count-1, 0))
4112 {
4113 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
4114 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
4115 break;
4116
4117 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
4118 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
4119 case 0: break; /* No 2xx or 5xx, but no probs */
4120
4121 case -1: goto END_OFF; /* Timeout on RCPT */
4122
4123 #ifndef DISABLE_PIPE_CONNECT
4124 case -5: /* TLS first-read error */
4125 case -4: HDEBUG(D_transport)
4126 debug_printf("failed reaping pipelined cmd responses\n");
4127 #endif
4128 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
4129 }
4130 }
4131
4132 #ifndef DISABLE_PRDR
4133 /* For PRDR we optionally get a partial-responses warning followed by the
4134 individual responses, before going on with the overall response. If we don't
4135 get the warning then deal with per non-PRDR. */
4136
4137 if(sx->prdr_active)
4138 {
4139 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '3', ob->final_timeout);
4140 if (!sx->ok && errno == 0) switch(sx->buffer[0])
4141 {
4142 case '2': sx->prdr_active = FALSE;
4143 sx->ok = TRUE;
4144 break;
4145 case '4': errno = ERRNO_DATA4XX;
4146 addrlist->more_errno |=
4147 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4148 break;
4149 }
4150 }
4151 else
4152 #endif
4153
4154 /* For non-PRDR SMTP, we now read a single response that applies to the
4155 whole message. If it is OK, then all the addresses have been delivered. */
4156
4157 if (!sx->lmtp)
4158 {
4159 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4160 ob->final_timeout);
4161 if (!sx->ok && errno == 0 && sx->buffer[0] == '4')
4162 {
4163 errno = ERRNO_DATA4XX;
4164 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4165 }
4166 }
4167
4168 /* For LMTP, we get back a response for every RCPT command that we sent;
4169 some may be accepted and some rejected. For those that get a response, their
4170 status is fixed; any that are accepted have been handed over, even if later
4171 responses crash - at least, that's how I read RFC 2033.
4172
4173 If all went well, mark the recipient addresses as completed, record which
4174 host/IPaddress they were delivered to, and cut out RSET when sending another
4175 message down the same channel. Write the completed addresses to the journal
4176 now so that they are recorded in case there is a crash of hardware or
4177 software before the spool gets updated. Also record the final SMTP
4178 confirmation if needed (for SMTP only). */
4179
4180 if (sx->ok)
4181 {
4182 int flag = '=';
4183 struct timeval delivery_time;
4184 int len;
4185 uschar * conf = NULL;
4186
4187 timesince(&delivery_time, &sx->delivery_start);
4188 sx->send_rset = FALSE;
4189 pipelining_active = FALSE;
4190
4191 /* Set up confirmation if needed - applies only to SMTP */
4192
4193 if (
4194 #ifdef DISABLE_EVENT
4195 LOGGING(smtp_confirmation) &&
4196 #endif
4197 !sx->lmtp
4198 )
4199 {
4200 const uschar * s = string_printing(sx->buffer);
4201 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4202 conf = s == sx->buffer ? US string_copy(s) : US s;
4203 }
4204
4205 /* Process all transported addresses - for LMTP or PRDR, read a status for
4206 each one. We used to drop out at first_addr, until someone returned a 452
4207 followed by a 250... and we screwed up the accepted addresses. */
4208
4209 for (address_item * addr = addrlist; addr; addr = addr->next)
4210 {
4211 if (addr->transport_return != PENDING_OK) continue;
4212
4213 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
4214 remaining addresses. Otherwise, it's a return code for just the one
4215 address. For temporary errors, add a retry item for the address so that
4216 it doesn't get tried again too soon. */
4217
4218 #ifndef DISABLE_PRDR
4219 if (sx->lmtp || sx->prdr_active)
4220 #else
4221 if (sx->lmtp)
4222 #endif
4223 {
4224 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4225 ob->final_timeout))
4226 {
4227 if (errno != 0 || sx->buffer[0] == 0) goto RESPONSE_FAILED;
4228 addr->message = string_sprintf(
4229 #ifndef DISABLE_PRDR
4230 "%s error after %s: %s", sx->prdr_active ? "PRDR":"LMTP",
4231 #else
4232 "LMTP error after %s: %s",
4233 #endif
4234 data_command, string_printing(sx->buffer));
4235 setflag(addr, af_pass_message); /* Allow message to go to user */
4236 if (sx->buffer[0] == '5')
4237 addr->transport_return = FAIL;
4238 else
4239 {
4240 errno = ERRNO_DATA4XX;
4241 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4242 addr->transport_return = DEFER;
4243 #ifndef DISABLE_PRDR
4244 if (!sx->prdr_active)
4245 #endif
4246 retry_add_item(addr, addr->address_retry_key, 0);
4247 }
4248 continue;
4249 }
4250 sx->completed_addr = TRUE; /* NOW we can set this flag */
4251 if (LOGGING(smtp_confirmation))
4252 {
4253 const uschar *s = string_printing(sx->buffer);
4254 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4255 conf = (s == sx->buffer) ? US string_copy(s) : US s;
4256 }
4257 }
4258
4259 /* SMTP, or success return from LMTP for this address. Pass back the
4260 actual host that was used. */
4261
4262 addr->transport_return = OK;
4263 addr->host_used = host;
4264 addr->delivery_time = delivery_time;
4265 addr->special_action = flag;
4266 addr->message = conf;
4267
4268 if (tcp_out_fastopen)
4269 {
4270 setflag(addr, af_tcp_fastopen_conn);
4271 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
4272 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
4273 }
4274 if (sx->pipelining_used) setflag(addr, af_pipelining);
4275 #ifndef DISABLE_PIPE_CONNECT
4276 if (sx->early_pipe_active) setflag(addr, af_early_pipe);
4277 #endif
4278 #ifndef DISABLE_PRDR
4279 if (sx->prdr_active) setflag(addr, af_prdr_used);
4280 #endif
4281 if (sx->peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
4282 flag = '-';
4283
4284 #ifndef DISABLE_PRDR
4285 if (!sx->prdr_active)
4286 #endif
4287 {
4288 /* Update the journal. For homonymic addresses, use the base address plus
4289 the transport name. See lots of comments in deliver.c about the reasons
4290 for the complications when homonyms are involved. Just carry on after
4291 write error, as it may prove possible to update the spool file later. */
4292
4293 if (testflag(addr, af_homonym))
4294 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4295 else
4296 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4297
4298 DEBUG(D_deliver) debug_printf("S:journalling %s", sx->buffer);
4299 len = Ustrlen(CS sx->buffer);
4300 if (write(journal_fd, sx->buffer, len) != len)
4301 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4302 "%s: %s", sx->buffer, strerror(errno));
4303 }
4304 }
4305
4306 #ifndef DISABLE_PRDR
4307 if (sx->prdr_active)
4308 {
4309 const uschar * overall_message;
4310
4311 /* PRDR - get the final, overall response. For any non-success
4312 upgrade all the address statuses. */
4313
4314 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4315 ob->final_timeout);
4316 if (!sx->ok)
4317 {
4318 if(errno == 0 && sx->buffer[0] == '4')
4319 {
4320 errno = ERRNO_DATA4XX;
4321 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4322 }
4323 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4324 if (sx->buffer[0] == '5' || addr->transport_return == OK)
4325 addr->transport_return = PENDING_OK; /* allow set_errno action */
4326 goto RESPONSE_FAILED;
4327 }
4328
4329 /* Append the overall response to the individual PRDR response for logging
4330 and update the journal, or setup retry. */
4331
4332 overall_message = string_printing(sx->buffer);
4333 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4334 if (addr->transport_return == OK)
4335 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
4336
4337 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4338 if (addr->transport_return == OK)
4339 {
4340 if (testflag(addr, af_homonym))
4341 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4342 else
4343 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4344
4345 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx->buffer);
4346 len = Ustrlen(CS sx->buffer);
4347 if (write(journal_fd, sx->buffer, len) != len)
4348 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4349 "%s: %s", sx->buffer, strerror(errno));
4350 }
4351 else if (addr->transport_return == DEFER)
4352 retry_add_item(addr, addr->address_retry_key, -2);
4353 }
4354 #endif
4355
4356 /* Ensure the journal file is pushed out to disk. */
4357
4358 if (EXIMfsync(journal_fd) < 0)
4359 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
4360 strerror(errno));
4361 }
4362 }
4363
4364
4365 /* Handle general (not specific to one address) failures here. The value of ok
4366 is used to skip over this code on the falling through case. A timeout causes a
4367 deferral. Other errors may defer or fail according to the response code, and
4368 may set up a special errno value, e.g. after connection chopped, which is
4369 assumed if errno == 0 and there is no text in the buffer. If control reaches
4370 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
4371 the problem is not related to this specific message. */
4372
4373 if (!sx->ok)
4374 {
4375 int code, set_rc;
4376 uschar * set_message;
4377
4378 RESPONSE_FAILED:
4379 {
4380 save_errno = errno;
4381 message = NULL;
4382 /* Clear send_quit flag if needed. Do not set. */
4383 sx->send_quit &= check_response(host, &save_errno, addrlist->more_errno,
4384 sx->buffer, &code, &message, &pass_message);
4385 goto FAILED;
4386 }
4387
4388 SEND_FAILED:
4389 {
4390 save_errno = errno;
4391 code = '4';
4392 message = string_sprintf("send() to %s [%s] failed: %s",
4393 host->name, host->address, message ? message : US strerror(save_errno));
4394 sx->send_quit = FALSE;
4395 goto FAILED;
4396 }
4397
4398 FAILED:
4399 {
4400 BOOL message_error;
4401
4402 sx->ok = FALSE; /* For when reached by GOTO */
4403 set_message = message;
4404
4405 /* We want to handle timeouts after MAIL or "." and loss of connection after
4406 "." specially. They can indicate a problem with the sender address or with
4407 the contents of the message rather than a real error on the connection. These
4408 cases are treated in the same way as a 4xx response. This next bit of code
4409 does the classification. */
4410
4411 switch(save_errno)
4412 {
4413 case 0:
4414 case ERRNO_MAIL4XX:
4415 case ERRNO_DATA4XX:
4416 message_error = TRUE;
4417 break;
4418
4419 case ETIMEDOUT:
4420 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4421 Ustrncmp(smtp_command,"end ",4) == 0;
4422 break;
4423
4424 case ERRNO_SMTPCLOSED:
4425 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4426 break;
4427
4428 #ifndef DISABLE_DKIM
4429 case EACCES:
4430 /* DKIM signing failure: avoid thinking we pipelined quit,
4431 just abandon the message and close the socket. */
4432
4433 message_error = FALSE;
4434 # ifndef DISABLE_TLS
4435 if (sx->cctx.tls_ctx)
4436 {
4437 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4438 sx->cctx.tls_ctx = NULL;
4439 }
4440 # endif
4441 break;
4442 #endif
4443 default:
4444 message_error = FALSE;
4445 break;
4446 }
4447
4448 /* Handle the cases that are treated as message errors. These are:
4449
4450 (a) negative response or timeout after MAIL
4451 (b) negative response after DATA
4452 (c) negative response or timeout or dropped connection after "."
4453 (d) utf8 support required and not offered
4454
4455 It won't be a negative response or timeout after RCPT, as that is dealt
4456 with separately above. The action in all cases is to set an appropriate
4457 error code for all the addresses, but to leave yield set to OK because the
4458 host itself has not failed. Of course, it might in practice have failed
4459 when we've had a timeout, but if so, we'll discover that at the next
4460 delivery attempt. For a temporary error, set the message_defer flag, and
4461 write to the logs for information if this is not the last host. The error
4462 for the last host will be logged as part of the address's log line. */
4463
4464 if (message_error)
4465 {
4466 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4467
4468 /* If there's an errno, the message contains just the identity of
4469 the host. */
4470
4471 if (code == '5')
4472 set_rc = FAIL;
4473 else /* Anything other than 5 is treated as temporary */
4474 {
4475 set_rc = DEFER;
4476 if (save_errno > 0)
4477 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4478
4479 write_logs(host, message, sx->first_addr ? sx->first_addr->basic_errno : 0);
4480
4481 *message_defer = TRUE;
4482 }
4483 #ifdef TIOCOUTQ
4484 DEBUG(D_transport) if (sx->cctx.sock >= 0)
4485 {
4486 int n;
4487 if (ioctl(sx->cctx.sock, TIOCOUTQ, &n) == 0)
4488 debug_printf("%d bytes remain in socket output buffer\n", n);
4489 }
4490 #endif
4491 }
4492 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4493 ".", or some other transportation error. We defer all addresses and yield
4494 DEFER, except for the case of failed add_headers expansion, or a transport
4495 filter failure, when the yield should be ERROR, to stop it trying other
4496 hosts. */
4497
4498 else
4499 {
4500 #ifndef DISABLE_PIPE_CONNECT
4501 /* If we were early-pipelinng and the actual EHLO response did not match
4502 the cached value we assumed, we could have detected it and passed a
4503 custom errno through to here. It would be nice to RSET and retry right
4504 away, but to reliably do that we eould need an extra synch point before
4505 we committed to data and that would discard half the gained roundrips.
4506 Or we could summarily drop the TCP connection. but that is also ugly.
4507 Instead, we ignore the possibility (having freshened the cache) and rely
4508 on the server telling us with a nonmessage error if we have tried to
4509 do something it no longer supports. */
4510 #endif
4511 set_rc = DEFER;
4512 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4513 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4514 }
4515 }
4516
4517 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host,
4518 #ifdef EXPERIMENTAL_DSN_INFO
4519 sx->smtp_greeting, sx->helo_response,
4520 #endif
4521 &sx->delivery_start);
4522 }
4523
4524 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4525 SMTP session tidily. However, if there were too many addresses to send in one
4526 message (indicated by first_addr being non-NULL) we want to carry on with the
4527 rest of them. Also, it is desirable to send more than one message down the SMTP
4528 connection if there are several waiting, provided we haven't already sent so
4529 many as to hit the configured limit. The function transport_check_waiting looks
4530 for a waiting message and returns its id. Then transport_pass_socket tries to
4531 set up a continued delivery by passing the socket on to another process. The
4532 variable send_rset is FALSE if a message has just been successfully transferred.
4533
4534 If we are already sending down a continued channel, there may be further
4535 addresses not yet delivered that are aimed at the same host, but which have not
4536 been passed in this run of the transport. In this case, continue_more will be
4537 true, and all we should do is send RSET if necessary, and return, leaving the
4538 channel open.
4539
4540 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4541 do not want to continue with other messages down the same channel, because that
4542 can lead to looping between two or more messages, all with the same,
4543 temporarily failing address(es). [The retry information isn't updated yet, so
4544 new processes keep on trying.] We probably also don't want to try more of this
4545 message's addresses either.
4546
4547 If we have started a TLS session, we have to end it before passing the
4548 connection to a new process. However, not all servers can handle this (Exim
4549 can), so we do not pass such a connection on if the host matches
4550 hosts_nopass_tls. */
4551
4552 DEBUG(D_transport)
4553 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4554 "yield=%d first_address is %sNULL\n", sx->ok, sx->send_quit,
4555 sx->send_rset, f.continue_more, yield, sx->first_addr ? "not " : "");
4556
4557 if (sx->completed_addr && sx->ok && sx->send_quit)
4558 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4559 if (mail_limit = continue_sequence >= sx->max_mail)
4560 {
4561 DEBUG(D_transport)
4562 debug_printf("reached limit %u for MAILs per conn\n", sx->max_mail);
4563 }
4564 else
4565 #endif
4566 {
4567 smtp_compare_t t_compare =
4568 {.tblock = tblock, .current_sender_address = sender_address};
4569
4570 if ( sx->first_addr /* more addrs for this message */
4571 || f.continue_more /* more addrs for continued-host */
4572 || tcw_done && tcw /* more messages for host */
4573 || (
4574 #ifndef DISABLE_TLS
4575 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4576 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4577 )
4578 &&
4579 #endif
4580 transport_check_waiting(tblock->name, host->name,
4581 sx->max_mail, new_message_id,
4582 (oicf)smtp_are_same_identities, (void*)&t_compare)
4583 ) )
4584 {
4585 uschar *msg;
4586 BOOL pass_message;
4587
4588 if (sx->send_rset)
4589 if (! (sx->ok = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4590 {
4591 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
4592 host->address, strerror(errno));
4593 sx->send_quit = FALSE;
4594 }
4595 else if (! (sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4596 '2', ob->command_timeout)))
4597 {
4598 int code;
4599 sx->send_quit = check_response(host, &errno, 0, sx->buffer, &code, &msg,
4600 &pass_message);
4601 if (!sx->send_quit)
4602 {
4603 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4604 host->name, host->address, msg);
4605 }
4606 }
4607
4608 /* Either RSET was not needed, or it succeeded */
4609
4610 if (sx->ok)
4611 {
4612 #ifndef DISABLE_TLS
4613 int pfd[2];
4614 #endif
4615 int socket_fd = sx->cctx.sock;
4616
4617 if (sx->first_addr) /* More addresses still to be sent */
4618 { /* for this message */
4619 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4620 /* Any that we marked as skipped, reset to do now */
4621 for (address_item * a = sx->first_addr; a; a = a->next)
4622 if (a->transport_return == SKIP)
4623 a->transport_return = PENDING_DEFER;
4624 #endif
4625 continue_sequence++; /* for consistency */
4626 clearflag(sx->first_addr, af_new_conn);
4627 setflag(sx->first_addr, af_cont_conn); /* Causes * in logging */
4628 pipelining_active = sx->pipelining_used; /* was cleared at DATA */
4629 goto SEND_MESSAGE;
4630 }
4631
4632 /* Unless caller said it already has more messages listed for this host,
4633 pass the connection on to a new Exim process (below, the call to
4634 transport_pass_socket). If the caller has more ready, just return with
4635 the connection still open. */
4636
4637 #ifndef DISABLE_TLS
4638 if (tls_out.active.sock >= 0)
4639 if ( f.continue_more
4640 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4641 {
4642 /* Before passing the socket on, or returning to caller with it still
4643 open, we must shut down TLS. Not all MTAs allow for the continuation
4644 of the SMTP session when TLS is shut down. We test for this by sending
4645 a new EHLO. If we don't get a good response, we don't attempt to pass
4646 the socket on. */
4647
4648 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4649 sx->send_tlsclose = FALSE;
4650 sx->cctx.tls_ctx = NULL;
4651 tls_out.active.sock = -1;
4652 smtp_peer_options = smtp_peer_options_wrap;
4653 sx->ok = !sx->smtps
4654 && smtp_write_command(sx, SCMD_FLUSH, "EHLO %s\r\n", sx->helo_data)
4655 >= 0
4656 && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4657 '2', ob->command_timeout);
4658
4659 if (sx->ok && f.continue_more)
4660 goto TIDYUP; /* More addresses for another run */
4661 }
4662 else
4663 {
4664 /* Set up a pipe for proxying TLS for the new transport process */
4665
4666 smtp_peer_options |= OPTION_TLS;
4667 if ((sx->ok = socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4668 socket_fd = pfd[1];
4669 else
4670 set_errno(sx->first_addr, errno, US"internal allocation problem",
4671 DEFER, FALSE, host,
4672 # ifdef EXPERIMENTAL_DSN_INFO
4673 sx->smtp_greeting, sx->helo_response,
4674 # endif
4675 &sx->delivery_start);
4676 }
4677 else
4678 #endif
4679 if (f.continue_more)
4680 goto TIDYUP; /* More addresses for another run */
4681
4682 /* If the socket is successfully passed, we mustn't send QUIT (or
4683 indeed anything!) from here. */
4684
4685 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4686 propagate it from the initial
4687 */
4688 if (sx->ok && transport_pass_socket(tblock->name, host->name,
4689 host->address, new_message_id, socket_fd
4690 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4691 , sx->peer_limit_mail, sx->peer_limit_rcpt, sx->peer_limit_rcptdom
4692 #endif
4693 ))
4694 {
4695 sx->send_quit = FALSE;
4696
4697 /* We have passed the client socket to a fresh transport process.
4698 If TLS is still active, we need to proxy it for the transport we
4699 just passed the baton to. Fork a child to to do it, and return to
4700 get logging done asap. Which way to place the work makes assumptions
4701 about post-fork prioritisation which may not hold on all platforms. */
4702 #ifndef DISABLE_TLS
4703 if (tls_out.active.sock >= 0)
4704 {
4705 int pid = exim_fork(US"tls-proxy-interproc");
4706 if (pid == 0) /* child; fork again to disconnect totally */
4707 {
4708 /* does not return */
4709 smtp_proxy_tls(sx->cctx.tls_ctx, sx->buffer, sizeof(sx->buffer), pfd,
4710 ob->command_timeout);
4711 }
4712
4713 if (pid > 0) /* parent */
4714 {
4715 close(pfd[0]);
4716 /* tidy the inter-proc to disconn the proxy proc */
4717 waitpid(pid, NULL, 0);
4718 tls_close(sx->cctx.tls_ctx, TLS_NO_SHUTDOWN);
4719 sx->cctx.tls_ctx = NULL;
4720 (void)close(sx->cctx.sock);
4721 sx->cctx.sock = -1;
4722 continue_transport = NULL;
4723 continue_hostname = NULL;
4724 goto TIDYUP;
4725 }
4726 log_write(0, LOG_PANIC_DIE, "fork failed");
4727 }
4728 #endif
4729 }
4730 }
4731
4732 /* If RSET failed and there are addresses left, they get deferred. */
4733 else
4734 set_errno(sx->first_addr, errno, msg, DEFER, FALSE, host,
4735 #ifdef EXPERIMENTAL_DSN_INFO
4736 sx->smtp_greeting, sx->helo_response,
4737 #endif
4738 &sx->delivery_start);
4739 }
4740 }
4741
4742 /* End off tidily with QUIT unless the connection has died or the socket has
4743 been passed to another process. */
4744
4745 SEND_QUIT:
4746 if (sx->send_quit)
4747 { /* Use _MORE to get QUIT in FIN segment */
4748 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4749 #ifndef DISABLE_TLS
4750 if (sx->cctx.tls_ctx)
4751 {
4752 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
4753 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4754 # endif
4755 tls_shutdown_wr(sx->cctx.tls_ctx);
4756 sx->send_tlsclose = FALSE;
4757 }
4758 #endif
4759 }
4760
4761 END_OFF:
4762
4763 /* Close the socket, and return the appropriate value, first setting
4764 works because the NULL setting is passed back to the calling process, and
4765 remote_max_parallel is forced to 1 when delivering over an existing connection,
4766
4767 If all went well and continue_more is set, we shouldn't actually get here if
4768 there are further addresses, as the return above will be taken. However,
4769 writing RSET might have failed, or there may be other addresses whose hosts are
4770 specified in the transports, and therefore not visible at top level, in which
4771 case continue_more won't get set. */
4772
4773 if (sx->send_quit)
4774 {
4775 /* This flushes data queued in the socket, being the QUIT and any TLS Close,
4776 sending them along with the client FIN flag. Us (we hope) sending FIN first
4777 means we (client) take the TIME_WAIT state, so the server (which likely has a
4778 higher connection rate) does not have to. */
4779
4780 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4781 shutdown(sx->cctx.sock, SHUT_WR);
4782 }
4783
4784 if (sx->send_quit || tcw_done && !tcw)
4785 {
4786 /* Wait for (we hope) ack of our QUIT, and a server FIN. Discard any data
4787 received, then discard the socket. Any packet received after then, or receive
4788 data still in the socket, will get a RST - hence the pause/drain. */
4789
4790 /* Reap the response to QUIT, timing out after one second */
4791 (void) smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', 1);
4792 #ifndef DISABLE_TLS
4793 if (sx->cctx.tls_ctx)
4794 {
4795 int n;
4796
4797 /* Reap the TLS Close Notify from the server, timing out after one second */
4798 sigalrm_seen = FALSE;
4799 ALARM(1);
4800 do
4801 n = tls_read(sx->cctx.tls_ctx, sx->inbuffer, sizeof(sx->inbuffer));
4802 while (!sigalrm_seen && n > 0);
4803 ALARM_CLR(0);
4804
4805 # ifdef EXIM_TCP_CORK
4806 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4807 # endif
4808 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4809 sx->cctx.tls_ctx = NULL;
4810 }
4811 #endif
4812 millisleep(20);
4813 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4814 for (int i = 16, n; /* drain socket */
4815 (n = read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer))) > 0 && i > 0;
4816 i--) HDEBUG(D_transport|D_acl|D_v)
4817 {
4818 int m = MIN(n, 64);
4819 debug_printf_indent(" SMTP(drain %d bytes)<< %.*s\n", n, m, sx->inbuffer);
4820 for (m = 0; m < n; m++)
4821 debug_printf("0x%02x\n", sx->inbuffer[m]);
4822 }
4823 }
4824 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4825 (void)close(sx->cctx.sock);
4826 sx->cctx.sock = -1;
4827 continue_transport = NULL;
4828 continue_hostname = NULL;
4829
4830 #ifndef DISABLE_EVENT
4831 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
4832 #endif
4833
4834 #ifdef SUPPORT_DANE
4835 if (dane_held)
4836 {
4837 sx->first_addr = NULL;
4838 for (address_item * a = sx->addrlist->next; a; a = a->next)
4839 if (a->transport_return == DANE)
4840 {
4841 a->transport_return = PENDING_DEFER;
4842 if (!sx->first_addr)
4843 {
4844 /* Remember the new start-point in the addrlist, for smtp_setup_conn()
4845 to get the domain string for SNI */
4846
4847 sx->first_addr = a;
4848 clearflag(a, af_cont_conn);
4849 setflag(a, af_new_conn); /* clear * from logging */
4850 DEBUG(D_transport) debug_printf("DANE: go-around for %s\n", a->domain);
4851 }
4852 }
4853 continue_sequence = 1; /* for consistency */
4854 goto REPEAT_CONN;
4855 }
4856 #endif
4857
4858 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4859 if (mail_limit && sx->first_addr)
4860 {
4861 /* Reset the sequence count since we closed the connection. This is flagged
4862 on the pipe back to the delivery process so that a non-continued-conn delivery
4863 is logged. */
4864
4865 continue_sequence = 1; /* for consistency */
4866 clearflag(sx->first_addr, af_cont_conn);
4867 setflag(sx->first_addr, af_new_conn); /* clear * from logging */
4868 goto REPEAT_CONN;
4869 }
4870 #endif
4871
4872 return yield;
4873
4874 TIDYUP:
4875 #ifdef SUPPORT_DANE
4876 if (dane_held) for (address_item * a = sx->addrlist->next; a; a = a->next)
4877 if (a->transport_return == DANE)
4878 a->transport_return = PENDING_DEFER;
4879 #endif
4880 return yield;
4881 }
4882
4883
4884
4885
4886 /*************************************************
4887 * Closedown entry point *
4888 *************************************************/
4889
4890 /* This function is called when exim is passed an open smtp channel
4891 from another incarnation, but the message which it has been asked
4892 to deliver no longer exists. The channel is on stdin.
4893
4894 We might do fancy things like looking for another message to send down
4895 the channel, but if the one we sought has gone, it has probably been
4896 delivered by some other process that itself will seek further messages,
4897 so just close down our connection.
4898
4899 Argument: pointer to the transport instance block
4900 Returns: nothing
4901 */
4902
4903 void
smtp_transport_closedown(transport_instance * tblock)4904 smtp_transport_closedown(transport_instance *tblock)
4905 {
4906 smtp_transport_options_block * ob = SOB tblock->options_block;
4907 client_conn_ctx cctx;
4908 smtp_context sx;
4909 uschar buffer[256];
4910 uschar inbuffer[4096];
4911 uschar outbuffer[16];
4912
4913 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4914 cctx.sock = fileno(stdin);
4915 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4916
4917 sx.inblock.cctx = &cctx;
4918 sx.inblock.buffer = inbuffer;
4919 sx.inblock.buffersize = sizeof(inbuffer);
4920 sx.inblock.ptr = inbuffer;
4921 sx.inblock.ptrend = inbuffer;
4922
4923 sx.outblock.cctx = &cctx;
4924 sx.outblock.buffersize = sizeof(outbuffer);
4925 sx.outblock.buffer = outbuffer;
4926 sx.outblock.ptr = outbuffer;
4927 sx.outblock.cmd_count = 0;
4928 sx.outblock.authenticating = FALSE;
4929
4930 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4931 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
4932 (void)close(cctx.sock);
4933 }
4934
4935
4936
4937 /*************************************************
4938 * Prepare addresses for delivery *
4939 *************************************************/
4940
4941 /* This function is called to flush out error settings from previous delivery
4942 attempts to other hosts. It also records whether we got here via an MX record
4943 or not in the more_errno field of the address. We are interested only in
4944 addresses that are still marked DEFER - others may have got delivered to a
4945 previously considered IP address. Set their status to PENDING_DEFER to indicate
4946 which ones are relevant this time.
4947
4948 Arguments:
4949 addrlist the list of addresses
4950 host the host we are delivering to
4951
4952 Returns: the first address for this delivery
4953 */
4954
4955 static address_item *
prepare_addresses(address_item * addrlist,host_item * host)4956 prepare_addresses(address_item *addrlist, host_item *host)
4957 {
4958 address_item *first_addr = NULL;
4959 for (address_item * addr = addrlist; addr; addr = addr->next)
4960 if (addr->transport_return == DEFER)
4961 {
4962 if (!first_addr) first_addr = addr;
4963 addr->transport_return = PENDING_DEFER;
4964 addr->basic_errno = 0;
4965 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
4966 addr->message = NULL;
4967 #ifndef DISABLE_TLS
4968 addr->cipher = NULL;
4969 addr->ourcert = NULL;
4970 addr->peercert = NULL;
4971 addr->peerdn = NULL;
4972 addr->ocsp = OCSP_NOT_REQ;
4973 addr->tlsver = NULL;
4974 #endif
4975 #ifdef EXPERIMENTAL_DSN_INFO
4976 addr->smtp_greeting = NULL;
4977 addr->helo_response = NULL;
4978 #endif
4979 }
4980 return first_addr;
4981 }
4982
4983
4984
4985 /*************************************************
4986 * Main entry point *
4987 *************************************************/
4988
4989 /* See local README for interface details. As this is a remote transport, it is
4990 given a chain of addresses to be delivered in one connection, if possible. It
4991 always returns TRUE, indicating that each address has its own independent
4992 status set, except if there is a setting up problem, in which case it returns
4993 FALSE. */
4994
4995 BOOL
smtp_transport_entry(transport_instance * tblock,address_item * addrlist)4996 smtp_transport_entry(
4997 transport_instance *tblock, /* data for this instantiation */
4998 address_item *addrlist) /* addresses we are working on */
4999 {
5000 int defport;
5001 int hosts_defer = 0;
5002 int hosts_fail = 0;
5003 int hosts_looked_up = 0;
5004 int hosts_retry = 0;
5005 int hosts_serial = 0;
5006 int hosts_total = 0;
5007 int total_hosts_tried = 0;
5008 BOOL expired = TRUE;
5009 uschar *expanded_hosts = NULL;
5010 uschar *pistring;
5011 uschar *tid = string_sprintf("%s transport", tblock->name);
5012 smtp_transport_options_block *ob = SOB tblock->options_block;
5013 host_item *hostlist = addrlist->host_list;
5014 host_item *host = NULL;
5015
5016 DEBUG(D_transport)
5017 {
5018 debug_printf("%s transport entered\n", tblock->name);
5019 for (address_item * addr = addrlist; addr; addr = addr->next)
5020 debug_printf(" %s\n", addr->address);
5021 if (hostlist)
5022 {
5023 debug_printf("hostlist:\n");
5024 for (host_item * host = hostlist; host; host = host->next)
5025 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
5026 }
5027 if (continue_hostname)
5028 debug_printf("already connected to %s [%s] (on fd %d)\n",
5029 continue_hostname, continue_host_address,
5030 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
5031 }
5032
5033 /* Check the restrictions on line length */
5034
5035 if (max_received_linelength > ob->message_linelength_limit)
5036 {
5037 struct timeval now;
5038 gettimeofday(&now, NULL);
5039
5040 for (address_item * addr = addrlist; addr; addr = addr->next)
5041 if (addr->transport_return == DEFER)
5042 addr->transport_return = PENDING_DEFER;
5043
5044 set_errno_nohost(addrlist, ERRNO_SMTPFORMAT,
5045 US"message has lines too long for transport", FAIL, TRUE, &now);
5046 goto END_TRANSPORT;
5047 }
5048
5049 /* Set the flag requesting that these hosts be added to the waiting
5050 database if the delivery fails temporarily or if we are running with
5051 queue_smtp or a 2-stage queue run. This gets unset for certain
5052 kinds of error, typically those that are specific to the message. */
5053
5054 update_waiting = TRUE;
5055
5056 /* If a host list is not defined for the addresses - they must all have the
5057 same one in order to be passed to a single transport - or if the transport has
5058 a host list with hosts_override set, use the host list supplied with the
5059 transport. It is an error for this not to exist. */
5060
5061 if (!hostlist || (ob->hosts_override && ob->hosts))
5062 {
5063 if (!ob->hosts)
5064 {
5065 addrlist->message = string_sprintf("%s transport called with no hosts set",
5066 tblock->name);
5067 addrlist->transport_return = PANIC;
5068 return FALSE; /* Only top address has status */
5069 }
5070
5071 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
5072 ob->hosts);
5073
5074 /* If the transport's host list contains no '$' characters, and we are not
5075 randomizing, it is fixed and therefore a chain of hosts can be built once
5076 and for all, and remembered for subsequent use by other calls to this
5077 transport. If, on the other hand, the host list does contain '$', or we are
5078 randomizing its order, we have to rebuild it each time. In the fixed case,
5079 as the hosts string will never be used again, it doesn't matter that we
5080 replace all the : characters with zeros. */
5081
5082 if (!ob->hostlist)
5083 {
5084 uschar *s = ob->hosts;
5085
5086 if (Ustrchr(s, '$'))
5087 {
5088 if (!(expanded_hosts = expand_string(s)))
5089 {
5090 addrlist->message = string_sprintf("failed to expand list of hosts "
5091 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
5092 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
5093 return FALSE; /* Only top address has status */
5094 }
5095 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
5096 "\"%s\"\n", s, expanded_hosts);
5097 s = expanded_hosts;
5098 }
5099 else
5100 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
5101
5102 if (is_tainted2(s, LOG_MAIN|LOG_PANIC, "Tainted host list '%s' from '%s' in transport %s", s, ob->hosts, tblock->name))
5103 {
5104 /* Avoid leaking info to an attacker */
5105 addrlist->message = US"internal configuration error";
5106 addrlist->transport_return = PANIC;
5107 return FALSE;
5108 }
5109
5110 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
5111
5112 /* Check that the expansion yielded something useful. */
5113 if (!hostlist)
5114 {
5115 addrlist->message =
5116 string_sprintf("%s transport has empty hosts setting", tblock->name);
5117 addrlist->transport_return = PANIC;
5118 return FALSE; /* Only top address has status */
5119 }
5120
5121 /* If there was no expansion of hosts, save the host list for
5122 next time. */
5123
5124 if (!expanded_hosts) ob->hostlist = hostlist;
5125 }
5126
5127 /* This is not the first time this transport has been run in this delivery;
5128 the host list was built previously. */
5129
5130 else
5131 hostlist = ob->hostlist;
5132 }
5133
5134 /* The host list was supplied with the address. If hosts_randomize is set, we
5135 must sort it into a random order if it did not come from MX records and has not
5136 already been randomized (but don't bother if continuing down an existing
5137 connection). */
5138
5139 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
5140 {
5141 host_item *newlist = NULL;
5142 while (hostlist)
5143 {
5144 host_item *h = hostlist;
5145 hostlist = hostlist->next;
5146
5147 h->sort_key = random_number(100);
5148
5149 if (!newlist)
5150 {
5151 h->next = NULL;
5152 newlist = h;
5153 }
5154 else if (h->sort_key < newlist->sort_key)
5155 {
5156 h->next = newlist;
5157 newlist = h;
5158 }
5159 else
5160 {
5161 host_item *hh = newlist;
5162 while (hh->next)
5163 {
5164 if (h->sort_key < hh->next->sort_key) break;
5165 hh = hh->next;
5166 }
5167 h->next = hh->next;
5168 hh->next = h;
5169 }
5170 }
5171
5172 hostlist = addrlist->host_list = newlist;
5173 }
5174
5175 /* Sort out the default port. */
5176
5177 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
5178
5179 /* For each host-plus-IP-address on the list:
5180
5181 . If this is a continued delivery and the host isn't the one with the
5182 current connection, skip.
5183
5184 . If the status is unusable (i.e. previously failed or retry checked), skip.
5185
5186 . If no IP address set, get the address, either by turning the name into
5187 an address, calling gethostbyname if gethostbyname is on, or by calling
5188 the DNS. The DNS may yield multiple addresses, in which case insert the
5189 extra ones into the list.
5190
5191 . Get the retry data if not previously obtained for this address and set the
5192 field which remembers the state of this address. Skip if the retry time is
5193 not reached. If not, remember whether retry data was found. The retry string
5194 contains both the name and the IP address.
5195
5196 . Scan the list of addresses and mark those whose status is DEFER as
5197 PENDING_DEFER. These are the only ones that will be processed in this cycle
5198 of the hosts loop.
5199
5200 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
5201 Some addresses may be successfully delivered, others may fail, and yet
5202 others may get temporary errors and so get marked DEFER.
5203
5204 . The return from the delivery attempt is OK if a connection was made and a
5205 valid SMTP dialogue was completed. Otherwise it is DEFER.
5206
5207 . If OK, add a "remove" retry item for this host/IPaddress, if any.
5208
5209 . If fail to connect, or other defer state, add a retry item.
5210
5211 . If there are any addresses whose status is still DEFER, carry on to the
5212 next host/IPaddress, unless we have tried the number of hosts given
5213 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
5214 there is some fancy logic for hosts_max_try that means its limit can be
5215 overstepped in some circumstances.
5216
5217 If we get to the end of the list, all hosts have deferred at least one address,
5218 or not reached their retry times. If delay_after_cutoff is unset, it requests a
5219 delivery attempt to those hosts whose last try was before the arrival time of
5220 the current message. To cope with this, we have to go round the loop a second
5221 time. After that, set the status and error data for any addresses that haven't
5222 had it set already. */
5223
5224 for (int cutoff_retry = 0;
5225 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
5226 cutoff_retry++)
5227 {
5228 host_item *nexthost = NULL;
5229 int unexpired_hosts_tried = 0;
5230 BOOL continue_host_tried = FALSE;
5231
5232 retry_non_continued:
5233 for (host = hostlist;
5234 host
5235 && unexpired_hosts_tried < ob->hosts_max_try
5236 && total_hosts_tried < ob->hosts_max_try_hardlimit;
5237 host = nexthost)
5238 {
5239 int rc;
5240 int host_af;
5241 BOOL host_is_expired = FALSE;
5242 BOOL message_defer = FALSE;
5243 BOOL some_deferred = FALSE;
5244 address_item *first_addr = NULL;
5245 uschar *interface = NULL;
5246 uschar *retry_host_key = NULL;
5247 uschar *retry_message_key = NULL;
5248 uschar *serialize_key = NULL;
5249
5250 /* Default next host is next host. :-) But this can vary if the
5251 hosts_max_try limit is hit (see below). It may also be reset if a host
5252 address is looked up here (in case the host was multihomed). */
5253
5254 nexthost = host->next;
5255
5256 /* If the address hasn't yet been obtained from the host name, look it up
5257 now, unless the host is already marked as unusable. If it is marked as
5258 unusable, it means that the router was unable to find its IP address (in
5259 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
5260 the lookup failed last time. We don't get this far if *all* MX records
5261 point to non-existent hosts; that is treated as a hard error.
5262
5263 We can just skip this host entirely. When the hosts came from the router,
5264 the address will timeout based on the other host(s); when the address is
5265 looked up below, there is an explicit retry record added.
5266
5267 Note that we mustn't skip unusable hosts if the address is not unset; they
5268 may be needed as expired hosts on the 2nd time round the cutoff loop. */
5269
5270 if (!host->address)
5271 {
5272 int new_port, flags;
5273
5274 if (host->status >= hstatus_unusable)
5275 {
5276 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
5277 host->name);
5278 continue;
5279 }
5280
5281 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
5282
5283 /* The host name is permitted to have an attached port. Find it, and
5284 strip it from the name. Just remember it for now. */
5285
5286 new_port = host_item_get_port(host);
5287
5288 /* Count hosts looked up */
5289
5290 hosts_looked_up++;
5291
5292 /* Find by name if so configured, or if it's an IP address. We don't
5293 just copy the IP address, because we need the test-for-local to happen. */
5294
5295 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
5296 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
5297 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
5298
5299 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
5300 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
5301 else
5302 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
5303 &ob->dnssec, /* domains for request/require */
5304 NULL, NULL);
5305
5306 /* Update the host (and any additional blocks, resulting from
5307 multihoming) with a host-specific port, if any. */
5308
5309 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
5310
5311 /* Failure to find the host at this time (usually DNS temporary failure)
5312 is really a kind of routing failure rather than a transport failure.
5313 Therefore we add a retry item of the routing kind, not to stop us trying
5314 to look this name up here again, but to ensure the address gets timed
5315 out if the failures go on long enough. A complete failure at this point
5316 commonly points to a configuration error, but the best action is still
5317 to carry on for the next host. */
5318
5319 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
5320 {
5321 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
5322 expired = FALSE;
5323 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
5324 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
5325 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
5326 host->status = hstatus_unusable;
5327
5328 for (address_item * addr = addrlist; addr; addr = addr->next)
5329 {
5330 if (addr->transport_return != DEFER) continue;
5331 addr->basic_errno = ERRNO_UNKNOWNHOST;
5332 addr->message = string_sprintf(
5333 rc == HOST_FIND_SECURITY
5334 ? "lookup of IP address for %s was insecure"
5335 : "failed to lookup IP address for %s",
5336 host->name);
5337 }
5338 continue;
5339 }
5340
5341 /* If the host is actually the local host, we may have a problem, or
5342 there may be some cunning configuration going on. In the problem case,
5343 log things and give up. The default transport status is already DEFER. */
5344
5345 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
5346 {
5347 for (address_item * addr = addrlist; addr; addr = addr->next)
5348 {
5349 addr->basic_errno = ERRNO_HOST_IS_LOCAL;
5350 addr->message = string_sprintf("%s transport found host %s to be "
5351 "local", tblock->name, host->name);
5352 }
5353 goto END_TRANSPORT;
5354 }
5355 } /* End of block for IP address lookup */
5356
5357 /* If this is a continued delivery, we are interested only in the host
5358 which matches the name of the existing open channel. The check is put
5359 here after the local host lookup, in case the name gets expanded as a
5360 result of the lookup. Set expired FALSE, to save the outer loop executing
5361 twice. */
5362
5363 if (continue_hostname)
5364 if ( Ustrcmp(continue_hostname, host->name) != 0
5365 || Ustrcmp(continue_host_address, host->address) != 0
5366 )
5367 {
5368 expired = FALSE;
5369 continue; /* With next host */
5370 }
5371 else
5372 continue_host_tried = TRUE;
5373
5374 /* Reset the default next host in case a multihomed host whose addresses
5375 are not looked up till just above added to the host list. */
5376
5377 nexthost = host->next;
5378
5379 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
5380 domain is in queue_smtp_domains, we don't actually want to attempt any
5381 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
5382 there is a lookup defer in queue_smtp_domains, proceed as if the domain
5383 were not in it. We don't want to hold up all SMTP deliveries! Except when
5384 doing a two-stage queue run, don't do this if forcing. */
5385
5386 if ( (!f.deliver_force || f.queue_2stage)
5387 && ( f.queue_smtp
5388 || match_isinlist(addrlist->domain,
5389 CUSS &queue_smtp_domains, 0,
5390 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK)
5391 )
5392 {
5393 DEBUG(D_transport) debug_printf("first-pass routing only\n");
5394 expired = FALSE;
5395 for (address_item * addr = addrlist; addr; addr = addr->next)
5396 if (addr->transport_return == DEFER)
5397 addr->message = US"first-pass only routing due to -odqs, "
5398 "queue_smtp_domains or control=queue";
5399 continue; /* With next host */
5400 }
5401
5402 /* Count hosts being considered - purely for an intelligent comment
5403 if none are usable. */
5404
5405 hosts_total++;
5406
5407 /* Set $host and $host address now in case they are needed for the
5408 interface expansion or the serialize_hosts check; they remain set if an
5409 actual delivery happens. */
5410
5411 deliver_host = host->name;
5412 deliver_host_address = host->address;
5413 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
5414 : host->dnssec == DS_NO ? US"no"
5415 : US"";
5416
5417 /* Set up a string for adding to the retry key if the port number is not
5418 the standard SMTP port. A host may have its own port setting that overrides
5419 the default. */
5420
5421 pistring = string_sprintf(":%d", host->port == PORT_NONE
5422 ? defport : host->port);
5423 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
5424
5425 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
5426 string is set, even if constant (as different transports can have different
5427 constant settings), we must add it to the key that is used for retries,
5428 because connections to the same host from a different interface should be
5429 treated separately. */
5430
5431 host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
5432 {
5433 uschar * s = ob->interface;
5434 if (s && *s)
5435 {
5436 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
5437 return FALSE;
5438 pistring = string_sprintf("%s/%s", pistring, interface);
5439 }
5440 }
5441
5442 /* The first time round the outer loop, check the status of the host by
5443 inspecting the retry data. The second time round, we are interested only
5444 in expired hosts that haven't been tried since this message arrived. */
5445
5446 if (cutoff_retry == 0)
5447 {
5448 BOOL incl_ip;
5449 /* Ensure the status of the address is set by checking retry data if
5450 necessary. There may be host-specific retry data (applicable to all
5451 messages) and also data for retries of a specific message at this host.
5452 If either of these retry records are actually read, the keys used are
5453 returned to save recomputing them later. */
5454
5455 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5456 US"retry_include_ip_address", ob->retry_include_ip_address,
5457 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5458 continue; /* with next host */
5459
5460 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
5461 incl_ip, &retry_host_key, &retry_message_key);
5462
5463 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
5464 host->address ? host->address : US"", pistring,
5465 host->status == hstatus_usable ? "usable"
5466 : host->status == hstatus_unusable ? "unusable"
5467 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
5468
5469 /* Skip this address if not usable at this time, noting if it wasn't
5470 actually expired, both locally and in the address. */
5471
5472 switch (host->status)
5473 {
5474 case hstatus_unusable:
5475 expired = FALSE;
5476 setflag(addrlist, af_retry_skipped);
5477 /* Fall through */
5478
5479 case hstatus_unusable_expired:
5480 switch (host->why)
5481 {
5482 case hwhy_retry: hosts_retry++; break;
5483 case hwhy_failed: hosts_fail++; break;
5484 case hwhy_insecure:
5485 case hwhy_deferred: hosts_defer++; break;
5486 }
5487
5488 /* If there was a retry message key, implying that previously there
5489 was a message-specific defer, we don't want to update the list of
5490 messages waiting for these hosts. */
5491
5492 if (retry_message_key) update_waiting = FALSE;
5493 continue; /* With the next host or IP address */
5494 }
5495 }
5496
5497 /* Second time round the loop: if the address is set but expired, and
5498 the message is newer than the last try, let it through. */
5499
5500 else
5501 {
5502 if ( !host->address
5503 || host->status != hstatus_unusable_expired
5504 || host->last_try > received_time.tv_sec)
5505 continue;
5506 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
5507 host->name, host->address, pistring);
5508 host_is_expired = TRUE;
5509 }
5510
5511 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
5512 it remains TRUE only if all hosts are expired and none are actually tried.
5513 */
5514
5515 expired = FALSE;
5516
5517 /* If this host is listed as one to which access must be serialized,
5518 see if another Exim process has a connection to it, and if so, skip
5519 this host. If not, update the database to record our connection to it
5520 and remember this for later deletion. Do not do any of this if we are
5521 sending the message down a pre-existing connection. */
5522
5523 if ( !continue_hostname
5524 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
5525 {
5526 serialize_key = string_sprintf("host-serialize-%s", host->name);
5527 if (!enq_start(serialize_key, 1))
5528 {
5529 DEBUG(D_transport)
5530 debug_printf("skipping host %s because another Exim process "
5531 "is connected to it\n", host->name);
5532 hosts_serial++;
5533 continue;
5534 }
5535 }
5536
5537 /* OK, we have an IP address that is not waiting for its retry time to
5538 arrive (it might be expired) OR (second time round the loop) we have an
5539 expired host that hasn't been tried since the message arrived. Have a go
5540 at delivering the message to it. First prepare the addresses by flushing
5541 out the result of previous attempts, and finding the first address that
5542 is still to be delivered. */
5543
5544 first_addr = prepare_addresses(addrlist, host);
5545
5546 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5547 message_id, host->name, host->address, addrlist->address,
5548 addrlist->next ? ", ..." : "");
5549
5550 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5551 message_id, host->name, host->address, pistring, addrlist->address,
5552 addrlist->next ? ", ..." : "");
5553
5554 /* This is not for real; don't do the delivery. If there are
5555 any remaining hosts, list them. */
5556
5557 if (f.dont_deliver)
5558 {
5559 struct timeval now;
5560 gettimeofday(&now, NULL);
5561 set_errno_nohost(addrlist, 0, NULL, OK, FALSE, &now);
5562 for (address_item * addr = addrlist; addr; addr = addr->next)
5563 {
5564 addr->host_used = host;
5565 addr->special_action = '*';
5566 addr->message = US"delivery bypassed by -N option";
5567 }
5568 DEBUG(D_transport)
5569 {
5570 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5571 "*** host and remaining hosts:\n", tblock->name);
5572 for (host_item * host2 = host; host2; host2 = host2->next)
5573 debug_printf(" %s [%s]\n", host2->name,
5574 host2->address ? host2->address : US"unset");
5575 }
5576 rc = OK;
5577 }
5578
5579 /* This is for real. If the host is expired, we don't count it for
5580 hosts_max_retry. This ensures that all hosts must expire before an address
5581 is timed out, unless hosts_max_try_hardlimit (which protects against
5582 lunatic DNS configurations) is reached.
5583
5584 If the host is not expired and we are about to hit the hosts_max_retry
5585 limit, check to see if there is a subsequent hosts with a different MX
5586 value. If so, make that the next host, and don't count this one. This is a
5587 heuristic to make sure that different MXs do get tried. With a normal kind
5588 of retry rule, they would get tried anyway when the earlier hosts were
5589 delayed, but if the domain has a "retry every time" type of rule - as is
5590 often used for the the very large ISPs, that won't happen. */
5591
5592 else
5593 {
5594 host_item * thost;
5595 /* Make a copy of the host if it is local to this invocation
5596 of the transport. */
5597
5598 if (expanded_hosts)
5599 {
5600 thost = store_get(sizeof(host_item), FALSE);
5601 *thost = *host;
5602 thost->name = string_copy(host->name);
5603 thost->address = string_copy(host->address);
5604 }
5605 else
5606 thost = host;
5607
5608 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5609 {
5610 DEBUG(D_transport)
5611 debug_printf("hosts_max_try limit reached with this host\n");
5612 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5613 {
5614 nexthost = h;
5615 unexpired_hosts_tried--;
5616 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5617 "and will be tried\n");
5618 break;
5619 }
5620 }
5621
5622 /* Attempt the delivery. */
5623
5624 total_hosts_tried++;
5625 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5626 &message_defer, FALSE);
5627
5628 /* Yield is one of:
5629 OK => connection made, each address contains its result;
5630 message_defer is set for message-specific defers (when all
5631 recipients are marked defer)
5632 DEFER => there was a non-message-specific delivery problem;
5633 ERROR => there was a problem setting up the arguments for a filter,
5634 or there was a problem with expanding added headers
5635 */
5636
5637 /* If the result is not OK, there was a non-message-specific problem.
5638 If the result is DEFER, we need to write to the logs saying what happened
5639 for this particular host, except in the case of authentication and TLS
5640 failures, where the log has already been written. If all hosts defer a
5641 general message is written at the end. */
5642
5643 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5644 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5645 write_logs(host, first_addr->message, first_addr->basic_errno);
5646
5647 #ifndef DISABLE_EVENT
5648 if (rc == DEFER)
5649 deferred_event_raise(first_addr, host, US"msg:host:defer");
5650 #endif
5651
5652 /* If STARTTLS was accepted, but there was a failure in setting up the
5653 TLS session (usually a certificate screwup), and the host is not in
5654 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5655 TLS forcibly turned off. We have to start from scratch with a new SMTP
5656 connection. That's why the retry is done from here, not from within
5657 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5658 session, so the in-clear transmission after those errors, if permitted,
5659 happens inside smtp_deliver().] */
5660
5661 #ifndef DISABLE_TLS
5662 if ( rc == DEFER
5663 && first_addr->basic_errno == ERRNO_TLSFAILURE
5664 && ob->tls_tempfail_tryclear
5665 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5666 )
5667 {
5668 log_write(0, LOG_MAIN,
5669 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5670 first_addr->message, host->name, host->address);
5671 first_addr = prepare_addresses(addrlist, host);
5672 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5673 &message_defer, TRUE);
5674 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5675 write_logs(host, first_addr->message, first_addr->basic_errno);
5676 # ifndef DISABLE_EVENT
5677 if (rc == DEFER)
5678 deferred_event_raise(first_addr, host, US"msg:host:defer");
5679 # endif
5680 }
5681 #endif /*DISABLE_TLS*/
5682
5683 #ifndef DISABLE_EVENT
5684 /* If the last host gave a defer raise a per-message event */
5685
5686 if ( !( nexthost
5687 && unexpired_hosts_tried < ob->hosts_max_try
5688 && total_hosts_tried < ob->hosts_max_try_hardlimit
5689 )
5690 && (message_defer || rc == DEFER)
5691 )
5692 deferred_event_raise(first_addr, host, US"msg:defer");
5693 #endif
5694 }
5695
5696 /* Delivery attempt finished */
5697
5698 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5699 message_id, host->name, host->address, pistring, addrlist->address,
5700 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5701
5702 /* Release serialization if set up */
5703
5704 if (serialize_key) enq_end(serialize_key);
5705
5706 /* If the result is DEFER, or if a host retry record is known to exist, we
5707 need to add an item to the retry chain for updating the retry database
5708 at the end of delivery. We only need to add the item to the top address,
5709 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5710 for any other delivery attempts using the same address. (It is copied into
5711 the unusable tree at the outer level, so even if different address blocks
5712 contain the same address, it still won't get tried again.) */
5713
5714 if (rc == DEFER || retry_host_key)
5715 {
5716 int delete_flag = rc != DEFER ? rf_delete : 0;
5717 if (!retry_host_key)
5718 {
5719 BOOL incl_ip;
5720 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5721 US"retry_include_ip_address", ob->retry_include_ip_address,
5722 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5723 incl_ip = TRUE; /* error; use most-specific retry record */
5724
5725 retry_host_key = incl_ip
5726 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5727 : string_sprintf("T:%S%s", host->name, pistring);
5728 }
5729
5730 /* If a delivery of another message over an existing SMTP connection
5731 yields DEFER, we do NOT set up retry data for the host. This covers the
5732 case when there are delays in routing the addresses in the second message
5733 that are so long that the server times out. This is alleviated by not
5734 routing addresses that previously had routing defers when handling an
5735 existing connection, but even so, this case may occur (e.g. if a
5736 previously happily routed address starts giving routing defers). If the
5737 host is genuinely down, another non-continued message delivery will
5738 notice it soon enough. */
5739
5740 if (delete_flag != 0 || !continue_hostname)
5741 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5742
5743 /* We may have tried an expired host, if its retry time has come; ensure
5744 the status reflects the expiry for the benefit of any other addresses. */
5745
5746 if (rc == DEFER)
5747 {
5748 host->status = host_is_expired
5749 ? hstatus_unusable_expired : hstatus_unusable;
5750 host->why = hwhy_deferred;
5751 }
5752 }
5753
5754 /* If message_defer is set (host was OK, but every recipient got deferred
5755 because of some message-specific problem), or if that had happened
5756 previously so that a message retry key exists, add an appropriate item
5757 to the retry chain. Note that if there was a message defer but now there is
5758 a host defer, the message defer record gets deleted. That seems perfectly
5759 reasonable. Also, stop the message from being remembered as waiting
5760 for specific hosts. */
5761
5762 if (message_defer || retry_message_key)
5763 {
5764 int delete_flag = message_defer ? 0 : rf_delete;
5765 if (!retry_message_key)
5766 {
5767 BOOL incl_ip;
5768 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5769 US"retry_include_ip_address", ob->retry_include_ip_address,
5770 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5771 incl_ip = TRUE; /* error; use most-specific retry record */
5772
5773 retry_message_key = incl_ip
5774 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5775 message_id)
5776 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5777 }
5778 retry_add_item(addrlist, retry_message_key,
5779 rf_message | rf_host | delete_flag);
5780 update_waiting = FALSE;
5781 }
5782
5783 /* Any return other than DEFER (that is, OK or ERROR) means that the
5784 addresses have got their final statuses filled in for this host. In the OK
5785 case, see if any of them are deferred. */
5786
5787 if (rc == OK)
5788 for (address_item * addr = addrlist; addr; addr = addr->next)
5789 if (addr->transport_return == DEFER)
5790 {
5791 some_deferred = TRUE;
5792 break;
5793 }
5794
5795 /* If no addresses deferred or the result was ERROR, return. We do this for
5796 ERROR because a failing filter set-up or add_headers expansion is likely to
5797 fail for any host we try. */
5798
5799 if (rc == ERROR || (rc == OK && !some_deferred))
5800 {
5801 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5802 return TRUE; /* Each address has its status */
5803 }
5804
5805 /* If the result was DEFER or some individual addresses deferred, let
5806 the loop run to try other hosts with the deferred addresses, except for the
5807 case when we were trying to deliver down an existing channel and failed.
5808 Don't try any other hosts in this case. */
5809
5810 if (continue_hostname) break;
5811
5812 /* If the whole delivery, or some individual addresses, were deferred and
5813 there are more hosts that could be tried, do not count this host towards
5814 the hosts_max_try limit if the age of the message is greater than the
5815 maximum retry time for this host. This means we may try try all hosts,
5816 ignoring the limit, when messages have been around for some time. This is
5817 important because if we don't try all hosts, the address will never time
5818 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5819
5820 if ((rc == DEFER || some_deferred) && nexthost)
5821 {
5822 BOOL timedout;
5823 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5824
5825 if (retry && retry->rules)
5826 {
5827 retry_rule *last_rule;
5828 for (last_rule = retry->rules;
5829 last_rule->next;
5830 last_rule = last_rule->next);
5831 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5832 }
5833 else timedout = TRUE; /* No rule => timed out */
5834
5835 if (timedout)
5836 {
5837 unexpired_hosts_tried--;
5838 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5839 "hosts_max_try (message older than host's retry time)\n");
5840 }
5841 }
5842
5843 DEBUG(D_transport)
5844 {
5845 if (unexpired_hosts_tried >= ob->hosts_max_try)
5846 debug_printf("reached transport hosts_max_try limit %d\n",
5847 ob->hosts_max_try);
5848 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5849 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5850 ob->hosts_max_try_hardlimit);
5851 }
5852
5853 testharness_pause_ms(500); /* let server debug out */
5854 } /* End of loop for trying multiple hosts. */
5855
5856 /* If we failed to find a matching host in the list, for an already-open
5857 connection, just close it and start over with the list. This can happen
5858 for routing that changes from run to run, or big multi-IP sites with
5859 round-robin DNS. */
5860
5861 if (continue_hostname && !continue_host_tried)
5862 {
5863 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5864
5865 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5866 #ifndef DISABLE_TLS
5867 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5868 transport */
5869 /*XXX doublecheck that! */
5870
5871 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5872 {
5873 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5874 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5875 cutthrough.cctx.tls_ctx = NULL;
5876 cutthrough.is_tls = FALSE;
5877 }
5878 else
5879 #else
5880 (void) write(fd, US"QUIT\r\n", 6);
5881 #endif
5882 (void) close(fd);
5883 cutthrough.cctx.sock = -1;
5884 continue_hostname = NULL;
5885 goto retry_non_continued;
5886 }
5887
5888 /* This is the end of the loop that repeats iff expired is TRUE and
5889 ob->delay_after_cutoff is FALSE. The second time round we will
5890 try those hosts that haven't been tried since the message arrived. */
5891
5892 DEBUG(D_transport)
5893 {
5894 debug_printf("all IP addresses skipped or deferred at least one address\n");
5895 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5896 debug_printf("retrying IP addresses not tried since message arrived\n");
5897 }
5898 }
5899
5900
5901 /* Get here if all IP addresses are skipped or defer at least one address. In
5902 MUA wrapper mode, this will happen only for connection or other non-message-
5903 specific failures. Force the delivery status for all addresses to FAIL. */
5904
5905 if (mua_wrapper)
5906 {
5907 for (address_item * addr = addrlist; addr; addr = addr->next)
5908 addr->transport_return = FAIL;
5909 goto END_TRANSPORT;
5910 }
5911
5912 /* In the normal, non-wrapper case, add a standard message to each deferred
5913 address if there hasn't been an error, that is, if it hasn't actually been
5914 tried this time. The variable "expired" will be FALSE if any deliveries were
5915 actually tried, or if there was at least one host that was not expired. That
5916 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
5917 a delivery has been tried, an error code will be set, and the failing of the
5918 message is handled by the retry code later.
5919
5920 If queue_smtp is set, or this transport was called to send a subsequent message
5921 down an existing TCP/IP connection, and something caused the host not to be
5922 found, we end up here, but can detect these cases and handle them specially. */
5923
5924 for (address_item * addr = addrlist; addr; addr = addr->next)
5925 {
5926 /* If host is not NULL, it means that we stopped processing the host list
5927 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
5928 means we need to behave as if some hosts were skipped because their retry
5929 time had not come. Specifically, this prevents the address from timing out.
5930 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
5931 hosts were tried. */
5932
5933 if (host)
5934 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5935 {
5936 DEBUG(D_transport)
5937 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
5938 "hosts were tried\n");
5939 }
5940 else
5941 {
5942 DEBUG(D_transport)
5943 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
5944 setflag(addr, af_retry_skipped);
5945 }
5946
5947 if (f.queue_smtp) /* no deliveries attempted */
5948 {
5949 addr->transport_return = DEFER;
5950 addr->basic_errno = 0;
5951 addr->message = US"SMTP delivery explicitly queued";
5952 }
5953
5954 else if ( addr->transport_return == DEFER
5955 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
5956 && !addr->message
5957 )
5958 {
5959 addr->basic_errno = ERRNO_HRETRY;
5960 if (continue_hostname)
5961 addr->message = US"no host found for existing SMTP connection";
5962 else if (expired)
5963 {
5964 setflag(addr, af_pass_message); /* This is not a security risk */
5965 addr->message = string_sprintf(
5966 "all hosts%s have been failing for a long time %s",
5967 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
5968 ob->delay_after_cutoff
5969 ? US"(and retry time not reached)"
5970 : US"and were last tried after this message arrived");
5971
5972 /* If we are already using fallback hosts, or there are no fallback hosts
5973 defined, convert the result to FAIL to cause a bounce. */
5974
5975 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
5976 addr->transport_return = FAIL;
5977 }
5978 else
5979 {
5980 const char * s;
5981 if (hosts_retry == hosts_total)
5982 s = "retry time not reached for any host%s";
5983 else if (hosts_fail == hosts_total)
5984 s = "all host address lookups%s failed permanently";
5985 else if (hosts_defer == hosts_total)
5986 s = "all host address lookups%s failed temporarily";
5987 else if (hosts_serial == hosts_total)
5988 s = "connection limit reached for all hosts%s";
5989 else if (hosts_fail+hosts_defer == hosts_total)
5990 s = "all host address lookups%s failed";
5991 else
5992 s = "some host address lookups failed and retry time "
5993 "not reached for other hosts or connection limit reached%s";
5994
5995 addr->message = string_sprintf(s,
5996 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
5997 }
5998 }
5999 }
6000
6001 /* Update the database which keeps information about which messages are waiting
6002 for which hosts to become available. For some message-specific errors, the
6003 update_waiting flag is turned off because we don't want follow-on deliveries in
6004 those cases. If this transport instance is explicitly limited to one message
6005 per connection then follow-on deliveries are not possible and there's no need
6006 to create/update the per-transport wait-<transport_name> database. */
6007
6008 if (update_waiting && tblock->connection_max_messages != 1)
6009 transport_update_waiting(hostlist, tblock->name);
6010
6011 END_TRANSPORT:
6012
6013 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
6014
6015 return TRUE; /* Each address has its status */
6016 }
6017
6018 #endif /*!MACRO_PREDEF*/
6019 /* vi: aw ai sw=2
6020 */
6021 /* End of transport/smtp.c */
6022