Remove details of errors in bounce and delay warning messages, unless
[exim.git] / src / src / transports / smtp.c
1 /* $Cambridge: exim/src/src/transports/smtp.c,v 1.11 2005/04/28 13:06:32 ph10 Exp $ */
2
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
6
7 /* Copyright (c) University of Cambridge 1995 - 2005 */
8 /* See the file NOTICE for conditions of use and distribution. */
9
10 #include "../exim.h"
11 #include "smtp.h"
12
13 #define PENDING 256
14 #define PENDING_DEFER (PENDING + DEFER)
15 #define PENDING_OK (PENDING + OK)
16
17
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
22
23 optionlist smtp_transport_options[] = {
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "command_timeout", opt_time,
29 (void *)offsetof(smtp_transport_options_block, command_timeout) },
30 { "connect_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
32 { "connection_max_messages", opt_int | opt_public,
33 (void *)offsetof(transport_instance, connection_max_messages) },
34 { "data_timeout", opt_time,
35 (void *)offsetof(smtp_transport_options_block, data_timeout) },
36 { "delay_after_cutoff", opt_bool,
37 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
38 #ifdef EXPERIMENTAL_DOMAINKEYS
39 { "dk_canon", opt_stringptr,
40 (void *)offsetof(smtp_transport_options_block, dk_canon) },
41 { "dk_domain", opt_stringptr,
42 (void *)offsetof(smtp_transport_options_block, dk_domain) },
43 { "dk_headers", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dk_headers) },
45 { "dk_private_key", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dk_private_key) },
47 { "dk_selector", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dk_selector) },
49 { "dk_strict", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dk_strict) },
51 #endif
52 { "dns_qualify_single", opt_bool,
53 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
54 { "dns_search_parents", opt_bool,
55 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
56 { "fallback_hosts", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
58 { "final_timeout", opt_time,
59 (void *)offsetof(smtp_transport_options_block, final_timeout) },
60 { "gethostbyname", opt_bool,
61 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
62 { "helo_data", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, helo_data) },
64 { "hosts", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, hosts) },
66 { "hosts_avoid_esmtp", opt_stringptr,
67 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
68 #ifdef SUPPORT_TLS
69 { "hosts_avoid_tls", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
71 #endif
72 { "hosts_max_try", opt_int,
73 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
74 { "hosts_max_try_hardlimit", opt_int,
75 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
76 #ifdef SUPPORT_TLS
77 { "hosts_nopass_tls", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
79 #endif
80 { "hosts_override", opt_bool,
81 (void *)offsetof(smtp_transport_options_block, hosts_override) },
82 { "hosts_randomize", opt_bool,
83 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
84 { "hosts_require_auth", opt_stringptr,
85 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
86 #ifdef SUPPORT_TLS
87 { "hosts_require_tls", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
89 #endif
90 { "hosts_try_auth", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
92 { "interface", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, interface) },
94 { "keepalive", opt_bool,
95 (void *)offsetof(smtp_transport_options_block, keepalive) },
96 { "max_rcpt", opt_int | opt_public,
97 (void *)offsetof(transport_instance, max_addresses) },
98 { "multi_domain", opt_bool | opt_public,
99 (void *)offsetof(transport_instance, multi_domain) },
100 { "port", opt_stringptr,
101 (void *)offsetof(smtp_transport_options_block, port) },
102 { "protocol", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, protocol) },
104 { "retry_include_ip_address", opt_bool,
105 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
106 { "serialize_hosts", opt_stringptr,
107 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
108 { "size_addition", opt_int,
109 (void *)offsetof(smtp_transport_options_block, size_addition) }
110 #ifdef SUPPORT_TLS
111 ,{ "tls_certificate", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
113 { "tls_crl", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, tls_crl) },
115 { "tls_privatekey", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
117 { "tls_require_ciphers", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
119 { "tls_tempfail_tryclear", opt_bool,
120 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
121 { "tls_verify_certificates", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
123 #endif
124 };
125
126 /* Size of the options list. An extern variable has to be used so that its
127 address can appear in the tables drtables.c. */
128
129 int smtp_transport_options_count =
130 sizeof(smtp_transport_options)/sizeof(optionlist);
131
132 /* Default private options block for the smtp transport. */
133
134 smtp_transport_options_block smtp_transport_option_defaults = {
135 NULL, /* hosts */
136 NULL, /* fallback_hosts */
137 NULL, /* hostlist */
138 NULL, /* fallback_hostlist */
139 NULL, /* authenticated_sender */
140 US"$primary_hostname", /* helo_data */
141 NULL, /* interface */
142 NULL, /* port */
143 US"smtp", /* protocol */
144 NULL, /* serialize_hosts */
145 NULL, /* hosts_try_auth */
146 NULL, /* hosts_require_auth */
147 NULL, /* hosts_require_tls */
148 NULL, /* hosts_avoid_tls */
149 NULL, /* hosts_avoid_esmtp */
150 NULL, /* hosts_nopass_tls */
151 5*60, /* command_timeout */
152 5*60, /* connect_timeout; shorter system default overrides */
153 5*60, /* data timeout */
154 10*60, /* final timeout */
155 1024, /* size_addition */
156 5, /* hosts_max_try */
157 50, /* hosts_max_try_hardlimit */
158 FALSE, /* allow_localhost */
159 FALSE, /* gethostbyname */
160 TRUE, /* dns_qualify_single */
161 FALSE, /* dns_search_parents */
162 TRUE, /* delay_after_cutoff */
163 FALSE, /* hosts_override */
164 FALSE, /* hosts_randomize */
165 TRUE, /* keepalive */
166 TRUE /* retry_include_ip_address */
167 #ifdef SUPPORT_TLS
168 ,NULL, /* tls_certificate */
169 NULL, /* tls_crl */
170 NULL, /* tls_privatekey */
171 NULL, /* tls_require_ciphers */
172 NULL, /* tls_verify_certificates */
173 TRUE /* tls_tempfail_tryclear */
174 #endif
175 #ifdef EXPERIMENTAL_DOMAINKEYS
176 ,NULL, /* dk_canon */
177 NULL, /* dk_domain */
178 NULL, /* dk_headers */
179 NULL, /* dk_private_key */
180 NULL, /* dk_selector */
181 NULL /* dk_strict */
182 #endif
183 };
184
185
186 /* Local statics */
187
188 static uschar *smtp_command; /* Points to last cmd for error messages */
189 static uschar *mail_command; /* Points to MAIL cmd for error messages */
190
191
192 /*************************************************
193 * Setup entry point *
194 *************************************************/
195
196 /* This function is called when the transport is about to be used,
197 but before running it in a sub-process. It is used for two things:
198
199 (1) To set the fallback host list in addresses, when delivering.
200 (2) To pass back the interface, port, and protocol options, for use during
201 callout verification.
202
203 Arguments:
204 tblock pointer to the transport instance block
205 addrlist list of addresses about to be transported
206 tf if not NULL, pointer to block in which to return options
207 errmsg place for error message (not used)
208
209 Returns: OK always (FAIL, DEFER not used)
210 */
211
212 static int
213 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
214 transport_feedback *tf, uschar **errmsg)
215 {
216 smtp_transport_options_block *ob =
217 (smtp_transport_options_block *)(tblock->options_block);
218
219 errmsg = errmsg; /* Keep picky compilers happy */
220
221 /* Pass back options if required. This interface is getting very messy. */
222
223 if (tf != NULL)
224 {
225 tf->interface = ob->interface;
226 tf->port = ob->port;
227 tf->protocol = ob->protocol;
228 tf->hosts = ob->hosts;
229 tf->hosts_override = ob->hosts_override;
230 tf->hosts_randomize = ob->hosts_randomize;
231 tf->gethostbyname = ob->gethostbyname;
232 tf->qualify_single = ob->dns_qualify_single;
233 tf->search_parents = ob->dns_search_parents;
234 }
235
236 /* Set the fallback host list for all the addresses that don't have fallback
237 host lists, provided that the local host wasn't present in the original host
238 list. */
239
240 if (!testflag(addrlist, af_local_host_removed))
241 {
242 for (; addrlist != NULL; addrlist = addrlist->next)
243 if (addrlist->fallback_hosts == NULL)
244 addrlist->fallback_hosts = ob->fallback_hostlist;
245 }
246
247 return OK;
248 }
249
250
251
252 /*************************************************
253 * Initialization entry point *
254 *************************************************/
255
256 /* Called for each instance, after its options have been read, to
257 enable consistency checks to be done, or anything else that needs
258 to be set up.
259
260 Argument: pointer to the transport instance block
261 Returns: nothing
262 */
263
264 void
265 smtp_transport_init(transport_instance *tblock)
266 {
267 smtp_transport_options_block *ob =
268 (smtp_transport_options_block *)(tblock->options_block);
269
270 /* Retry_use_local_part defaults FALSE if unset */
271
272 if (tblock->retry_use_local_part == TRUE_UNSET)
273 tblock->retry_use_local_part = FALSE;
274
275 /* Set the default port according to the protocol */
276
277 if (ob->port == NULL)
278 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" : US"smtp";
279
280 /* Set up the setup entry point, to be called before subprocesses for this
281 transport. */
282
283 tblock->setup = smtp_transport_setup;
284
285 /* Complain if any of the timeouts are zero. */
286
287 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
288 ob->final_timeout <= 0)
289 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
290 "command, data, or final timeout value is zero for %s transport",
291 tblock->name);
292
293 /* If hosts_override is set and there are local hosts, set the global
294 flag that stops verify from showing router hosts. */
295
296 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
297
298 /* If there are any fallback hosts listed, build a chain of host items
299 for them, but do not do any lookups at this time. */
300
301 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
302 }
303
304
305
306
307
308 /*************************************************
309 * Set delivery info into all active addresses *
310 *************************************************/
311
312 /* Only addresses whose status is >= PENDING are relevant. A lesser
313 status means that an address is not currently being processed.
314
315 Arguments:
316 addrlist points to a chain of addresses
317 errno_value to put in each address's errno field
318 msg to put in each address's message field
319 rc to put in each address's transport_return field
320 pass_message if TRUE, set the "pass message" flag in the address
321
322 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
323 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
324 this particular type of timeout.
325
326 Returns: nothing
327 */
328
329 static
330 void set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
331 BOOL pass_message)
332 {
333 address_item *addr;
334 int orvalue = 0;
335 if (errno_value == ERRNO_CONNECTTIMEOUT)
336 {
337 errno_value = ETIMEDOUT;
338 orvalue = RTEF_CTOUT;
339 }
340 for (addr = addrlist; addr != NULL; addr = addr->next)
341 {
342 if (addr->transport_return < PENDING) continue;
343 addr->basic_errno = errno_value;
344 addr->more_errno |= orvalue;
345 if (msg != NULL)
346 {
347 addr->message = msg;
348 if (pass_message) setflag(addr, af_pass_message);
349 }
350 addr->transport_return = rc;
351 }
352 }
353
354
355
356 /*************************************************
357 * Check an SMTP response *
358 *************************************************/
359
360 /* This function is given an errno code and the SMTP response buffer
361 to analyse, together with the host identification for generating messages. It
362 sets an appropriate message and puts the first digit of the response code into
363 the yield variable. If no response was actually read, a suitable digit is
364 chosen.
365
366 Arguments:
367 host the current host, to get its name for messages
368 errno_value pointer to the errno value
369 more_errno from the top address for use with ERRNO_FILTER_FAIL
370 buffer the SMTP response buffer
371 yield where to put a one-digit SMTP response code
372 message where to put an errror message
373 pass_message set TRUE if message is an SMTP response
374
375 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
376 */
377
378 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
379 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
380 {
381 uschar *pl = US"";
382
383 if (smtp_use_pipelining &&
384 (Ustrcmp(smtp_command, "MAIL") == 0 ||
385 Ustrcmp(smtp_command, "RCPT") == 0 ||
386 Ustrcmp(smtp_command, "DATA") == 0))
387 pl = US"pipelined ";
388
389 *yield = '4'; /* Default setting is to give a temporary error */
390
391 /* Handle response timeout */
392
393 if (*errno_value == ETIMEDOUT)
394 {
395 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
396 "after %s%s", host->name, host->address, pl, smtp_command);
397 if (transport_count > 0)
398 *message = US string_sprintf("%s (%d bytes written)", *message,
399 transport_count);
400 return FALSE;
401 }
402
403 /* Handle malformed SMTP response */
404
405 if (*errno_value == ERRNO_SMTPFORMAT)
406 {
407 uschar *malfresp = string_printing(buffer);
408 while (isspace(*malfresp)) malfresp++;
409 if (*malfresp == 0)
410 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
411 "%s [%s] in response to %s%s", host->name, host->address, pl,
412 smtp_command);
413 else
414 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
415 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
416 return FALSE;
417 }
418
419 /* Handle a failed filter process error; can't send QUIT as we mustn't
420 end the DATA. */
421
422 if (*errno_value == ERRNO_FILTER_FAIL)
423 {
424 *message = US string_sprintf("transport filter process failed (%d)%s",
425 more_errno,
426 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
427 return FALSE;
428 }
429
430 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
431 end the DATA. */
432
433 if (*errno_value == ERRNO_CHHEADER_FAIL)
434 {
435 *message =
436 US string_sprintf("failed to expand headers_add or headers_remove: %s",
437 expand_string_message);
438 return FALSE;
439 }
440
441 /* Handle failure to write a complete data block */
442
443 if (*errno_value == ERRNO_WRITEINCOMPLETE)
444 {
445 *message = US string_sprintf("failed to write a data block");
446 return FALSE;
447 }
448
449 /* Handle error responses from the remote mailer. */
450
451 if (buffer[0] != 0)
452 {
453 uschar *s = string_printing(buffer);
454 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
455 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
456 *pass_message = TRUE;
457 *yield = buffer[0];
458 return TRUE;
459 }
460
461 /* No data was read. If there is no errno, this must be the EOF (i.e.
462 connection closed) case, which causes deferral. Otherwise, put the host's
463 identity in the message, leaving the errno value to be interpreted as well. In
464 all cases, we have to assume the connection is now dead. */
465
466 if (*errno_value == 0)
467 {
468 *errno_value = ERRNO_SMTPCLOSED;
469 *message = US string_sprintf("Remote host %s [%s] closed connection "
470 "in response to %s%s", host->name, host->address, pl, smtp_command);
471 }
472 else *message = US string_sprintf("%s [%s]", host->name, host->address);
473
474 return FALSE;
475 }
476
477
478
479 /*************************************************
480 * Write error message to logs *
481 *************************************************/
482
483 /* This writes to the main log and to the message log.
484
485 Arguments:
486 addr the address item containing error information
487 host the current host
488
489 Returns: nothing
490 */
491
492 static void
493 write_logs(address_item *addr, host_item *host)
494 {
495 if (addr->message != NULL)
496 {
497 uschar *message = addr->message;
498 if (addr->basic_errno > 0)
499 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
500 log_write(0, LOG_MAIN, "%s", message);
501 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
502 }
503 else
504 {
505 log_write(0, LOG_MAIN, "%s [%s]: %s",
506 host->name,
507 host->address,
508 strerror(addr->basic_errno));
509 deliver_msglog("%s %s [%s]: %s\n",
510 tod_stamp(tod_log),
511 host->name,
512 host->address,
513 strerror(addr->basic_errno));
514 }
515 }
516
517
518
519 /*************************************************
520 * Synchronize SMTP responses *
521 *************************************************/
522
523 /* This function is called from smtp_deliver() to receive SMTP responses from
524 the server, and match them up with the commands to which they relate. When
525 PIPELINING is not in use, this function is called after every command, and is
526 therefore somewhat over-engineered, but it is simpler to use a single scheme
527 that works both with and without PIPELINING instead of having two separate sets
528 of code.
529
530 The set of commands that are buffered up with pipelining may start with MAIL
531 and may end with DATA; in between are RCPT commands that correspond to the
532 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
533 etc.) are never buffered.
534
535 Errors after MAIL or DATA abort the whole process leaving the response in the
536 buffer. After MAIL, pending responses are flushed, and the original command is
537 re-instated in big_buffer for error messages. For RCPT commands, the remote is
538 permitted to reject some recipient addresses while accepting others. However
539 certain errors clearly abort the whole process. Set the value in
540 transport_return to PENDING_OK if the address is accepted. If there is a
541 subsequent general error, it will get reset accordingly. If not, it will get
542 converted to OK at the end.
543
544 Arguments:
545 addrlist the complete address list
546 include_affixes TRUE if affixes include in RCPT
547 sync_addr ptr to the ptr of the one to start scanning at (updated)
548 host the host we are connected to
549 count the number of responses to read
550 pending_MAIL true if the first response is for MAIL
551 pending_DATA 0 if last command sent was not DATA
552 +1 if previously had a good recipient
553 -1 if not previously had a good recipient
554 inblock incoming SMTP block
555 timeout timeout value
556 buffer buffer for reading response
557 buffsize size of buffer
558
559 Returns: 3 if at least one address had 2xx and one had 5xx
560 2 if at least one address had 5xx but none had 2xx
561 1 if at least one host had a 2xx response, but none had 5xx
562 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
563 -1 timeout while reading RCPT response
564 -2 I/O or other non-response error for RCPT
565 -3 DATA or MAIL failed - errno and buffer set
566 */
567
568 static int
569 sync_responses(address_item *addrlist, BOOL include_affixes,
570 address_item **sync_addr, host_item *host, int count, BOOL pending_MAIL,
571 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
572 int buffsize)
573 {
574 address_item *addr = *sync_addr;
575 int yield = 0;
576
577 /* Handle the response for a MAIL command. On error, reinstate the original
578 command in big_buffer for error message use, and flush any further pending
579 responses before returning, except after I/O errors and timeouts. */
580
581 if (pending_MAIL)
582 {
583 count--;
584 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
585 {
586 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
587 if (errno == 0 && buffer[0] != 0)
588 {
589 uschar flushbuffer[4096];
590 while (count-- > 0)
591 {
592 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
593 '2', timeout)
594 && (errno != 0 || flushbuffer[0] == 0))
595 break;
596 }
597 }
598 return -3;
599 }
600 }
601
602 if (pending_DATA) count--; /* Number of RCPT responses to come */
603
604 /* Read and handle the required number of RCPT responses, matching each one up
605 with an address by scanning for the next address whose status is PENDING_DEFER.
606 */
607
608 while (count-- > 0)
609 {
610 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
611
612 /* The address was accepted */
613
614 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
615 {
616 yield |= 1;
617 addr->transport_return = PENDING_OK;
618
619 /* If af_dr_retry_exists is set, there was a routing delay on this address;
620 ensure that any address-specific retry record is expunged. */
621
622 if (testflag(addr, af_dr_retry_exists))
623 retry_add_item(addr, addr->address_retry_key, rf_delete);
624 }
625
626 /* Timeout while reading the response */
627
628 else if (errno == ETIMEDOUT)
629 {
630 int save_errno = errno;
631 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
632 "after RCPT TO:<%s>", host->name, host->address,
633 transport_rcpt_address(addr, include_affixes));
634 set_errno(addrlist, save_errno, message, DEFER, FALSE);
635 retry_add_item(addr, addr->address_retry_key, 0);
636 host->update_waiting = FALSE;
637 return -1;
638 }
639
640 /* Handle other errors in obtaining an SMTP response by returning -1. This
641 will cause all the addresses to be deferred. Restore the SMTP command in
642 big_buffer for which we are checking the response, so the error message
643 makes sense. */
644
645 else if (errno != 0 || buffer[0] == 0)
646 {
647 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
648 transport_rcpt_address(addr, include_affixes));
649 return -2;
650 }
651
652 /* Handle SMTP permanent and temporary response codes. */
653
654 else
655 {
656 addr->message =
657 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
658 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
659 host->name, host->address, string_printing(buffer));
660 setflag(addr, af_pass_message);
661 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
662
663 /* The response was 5xx */
664
665 if (buffer[0] == '5')
666 {
667 addr->transport_return = FAIL;
668 yield |= 2;
669 }
670
671 /* The response was 4xx */
672
673 else
674 {
675 int bincode = (buffer[1] - '0')*10 + buffer[2] - '0';
676
677 addr->transport_return = DEFER;
678 addr->basic_errno = ERRNO_RCPT4XX;
679 addr->more_errno |= bincode << 8;
680
681 /* Log temporary errors if there are more hosts to be tried. */
682
683 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
684
685 /* Do not put this message on the list of those waiting for this host,
686 as otherwise it is likely to be tried too often. */
687
688 host->update_waiting = FALSE;
689
690 /* Add a retry item for the address so that it doesn't get tried
691 again too soon. */
692
693 retry_add_item(addr, addr->address_retry_key, 0);
694 }
695 }
696 } /* Loop for next RCPT response */
697
698 /* Update where to start at for the next block of responses, unless we
699 have already handled all the addresses. */
700
701 if (addr != NULL) *sync_addr = addr->next;
702
703 /* Handle a response to DATA. If we have not had any good recipients, either
704 previously or in this block, the response is ignored. */
705
706 if (pending_DATA != 0 &&
707 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
708 {
709 int code;
710 uschar *msg;
711 BOOL pass_message;
712 if (pending_DATA > 0 || (yield & 1) != 0) return -3;
713 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
714 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
715 "is in use and there were no good recipients\n", msg);
716 }
717
718 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
719 present) received 3xx. If any RCPTs were handled and yielded anything other
720 than 4xx, yield will be set non-zero. */
721
722 return yield;
723 }
724
725
726
727 /*************************************************
728 * Deliver address list to given host *
729 *************************************************/
730
731 /* If continue_hostname is not null, we get here only when continuing to
732 deliver down an existing channel. The channel was passed as the standard
733 input.
734
735 Otherwise, we have to make a connection to the remote host, and do the
736 initial protocol exchange.
737
738 When running as an MUA wrapper, if the sender or any recipient is rejected,
739 temporarily or permanently, we force failure for all recipients.
740
741 Arguments:
742 addrlist chain of potential addresses to deliver; only those whose
743 transport_return field is set to PENDING_DEFER are currently
744 being processed; others should be skipped - they have either
745 been delivered to an earlier host or IP address, or been
746 failed by one of them.
747 host host to deliver to
748 host_af AF_INET or AF_INET6
749 port TCP/IP port to use, in host byte order
750 interface interface to bind to, or NULL
751 tblock transport instance block
752 copy_host TRUE if host set in addr->host_used must be copied, because
753 it is specific to this call of the transport
754 message_defer set TRUE if yield is OK, but all addresses were deferred
755 because of a non-recipient, non-host failure, that is, a
756 4xx response to MAIL FROM, DATA, or ".". This is a defer
757 that is specific to the message.
758 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
759 a second attempt after TLS initialization fails
760
761 Returns: OK - the connection was made and the delivery attempted;
762 the result for each address is in its data block.
763 DEFER - the connection could not be made, or something failed
764 while setting up the SMTP session, or there was a
765 non-message-specific error, such as a timeout.
766 ERROR - a filter command is specified for this transport,
767 and there was a problem setting it up; OR helo_data
768 or add_headers or authenticated_sender is specified
769 for this transport, and the string failed to expand
770 */
771
772 static int
773 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
774 uschar *interface, transport_instance *tblock, BOOL copy_host,
775 BOOL *message_defer, BOOL suppress_tls)
776 {
777 address_item *addr;
778 address_item *sync_addr;
779 address_item *first_addr = addrlist;
780 int yield = OK;
781 int address_count;
782 int save_errno;
783 int rc;
784 time_t start_delivery_time = time(NULL);
785 smtp_transport_options_block *ob =
786 (smtp_transport_options_block *)(tblock->options_block);
787 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
788 BOOL ok = FALSE;
789 BOOL send_rset = TRUE;
790 BOOL send_quit = TRUE;
791 BOOL setting_up = TRUE;
792 BOOL completed_address = FALSE;
793 BOOL esmtp = TRUE;
794 BOOL pending_MAIL;
795 BOOL pass_message = FALSE;
796 smtp_inblock inblock;
797 smtp_outblock outblock;
798 int max_rcpt = tblock->max_addresses;
799 uschar *local_authenticated_sender = authenticated_sender;
800 uschar *helo_data;
801 uschar *message = NULL;
802 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
803 uschar *p;
804 uschar buffer[4096];
805 uschar inbuffer[4096];
806 uschar outbuffer[1024];
807
808 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
809
810 *message_defer = FALSE;
811 smtp_command = US"initial connection";
812 if (max_rcpt == 0) max_rcpt = 999999;
813
814 /* Set up the buffer for reading SMTP response packets. */
815
816 inblock.buffer = inbuffer;
817 inblock.buffersize = sizeof(inbuffer);
818 inblock.ptr = inbuffer;
819 inblock.ptrend = inbuffer;
820
821 /* Set up the buffer for holding SMTP commands while pipelining */
822
823 outblock.buffer = outbuffer;
824 outblock.buffersize = sizeof(outbuffer);
825 outblock.ptr = outbuffer;
826 outblock.cmd_count = 0;
827 outblock.authenticating = FALSE;
828
829 /* Expand the greeting message */
830
831 helo_data = expand_string(ob->helo_data);
832 if (helo_data == NULL)
833 {
834 uschar *message = string_sprintf("failed to expand helo_data: %s",
835 expand_string_message);
836 set_errno(addrlist, 0, message, DEFER, FALSE);
837 return ERROR;
838 }
839
840 /* If an authenticated_sender override has been specified for this transport
841 instance, expand it. If the expansion is forced to fail, and there was already
842 an authenticated_sender for this message, the original value will be used.
843 Other expansion failures are serious. An empty result is ignored, but there is
844 otherwise no check - this feature is expected to be used with LMTP and other
845 cases where non-standard addresses (e.g. without domains) might be required. */
846
847 if (ob->authenticated_sender != NULL)
848 {
849 uschar *new = expand_string(ob->authenticated_sender);
850 if (new == NULL)
851 {
852 if (!expand_string_forcedfail)
853 {
854 uschar *message = string_sprintf("failed to expand "
855 "authenticated_sender: %s", expand_string_message);
856 set_errno(addrlist, 0, message, DEFER, FALSE);
857 return ERROR;
858 }
859 }
860 else if (new[0] != 0) local_authenticated_sender = new;
861 }
862
863 /* Make a connection to the host if this isn't a continued delivery, and handle
864 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
865 specially so they can be identified for retries. */
866
867 if (continue_hostname == NULL)
868 {
869 inblock.sock = outblock.sock =
870 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
871 ob->keepalive);
872 if (inblock.sock < 0)
873 {
874 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
875 NULL, DEFER, FALSE);
876 return DEFER;
877 }
878
879 /* The first thing is to wait for an initial OK response. The dreaded "goto"
880 is nevertheless a reasonably clean way of programming this kind of logic,
881 where you want to escape on any error. */
882
883 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
884 ob->command_timeout)) goto RESPONSE_FAILED;
885
886 /** Debugging without sending a message
887 addrlist->transport_return = DEFER;
888 goto SEND_QUIT;
889 **/
890
891 /* Errors that occur after this point follow an SMTP command, which is
892 left in big_buffer by smtp_write_command() for use in error messages. */
893
894 smtp_command = big_buffer;
895
896 /* Tell the remote who we are...
897
898 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
899 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
900 greeting is of this form. The assumption was that the far end supports it
901 properly... but experience shows that there are some that give 5xx responses,
902 even though the banner includes "ESMTP" (there's a bloody-minded one that
903 says "ESMTP not spoken here"). Cope with that case.
904
905 September 2000: Time has passed, and it seems reasonable now to always send
906 EHLO at the start. It is also convenient to make the change while installing
907 the TLS stuff.
908
909 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
910 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
911 would be no way to send out the mails, so there is now a host list
912 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
913 PIPELINING problem as well. Maybe it can also be useful to cure other
914 problems with broken servers.
915
916 Exim originally sent "Helo" at this point and ran for nearly a year that way.
917 Then somebody tried it with a Microsoft mailer... It seems that all other
918 mailers use upper case for some reason (the RFC is quite clear about case
919 independence) so, for peace of mind, I gave in. */
920
921 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
922 host->name, host->address, NULL) != OK;
923
924 if (esmtp)
925 {
926 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
927 lmtp? "LHLO" : "EHLO", helo_data) < 0)
928 goto SEND_FAILED;
929 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
930 ob->command_timeout))
931 {
932 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
933 esmtp = FALSE;
934 }
935 }
936 else
937 {
938 DEBUG(D_transport)
939 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
940 }
941
942 if (!esmtp)
943 {
944 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
945 goto SEND_FAILED;
946 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
947 ob->command_timeout)) goto RESPONSE_FAILED;
948 }
949
950 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
951
952 #ifdef SUPPORT_TLS
953 tls_offered = esmtp &&
954 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
955 PCRE_EOPT, NULL, 0) >= 0;
956 #endif
957 }
958
959 /* For continuing deliveries down the same channel, the socket is the standard
960 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
961 below). Set up the pointer to where subsequent commands will be left, for
962 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
963 set from the command line if they were set in the process that passed the
964 connection on. */
965
966 else
967 {
968 inblock.sock = outblock.sock = fileno(stdin);
969 smtp_command = big_buffer;
970 }
971
972 /* If TLS is available on this connection, whether continued or not, attempt to
973 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
974 send another EHLO - the server may give a different answer in secure mode. We
975 use a separate buffer for reading the response to STARTTLS so that if it is
976 negative, the original EHLO data is available for subsequent analysis, should
977 the client not be required to use TLS. If the response is bad, copy the buffer
978 for error analysis. */
979
980 #ifdef SUPPORT_TLS
981 if (tls_offered && !suppress_tls &&
982 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
983 host->address, NULL) != OK)
984 {
985 uschar buffer2[4096];
986 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
987 goto SEND_FAILED;
988
989 /* If there is an I/O error, transmission of this message is deferred. If
990 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
991 false, we also defer. However, if there is a temporary rejection of STARTTLS
992 and tls_tempfail_tryclear is true, or if there is an outright rejection of
993 STARTTLS, we carry on. This means we will try to send the message in clear,
994 unless the host is in hosts_require_tls (tested below). */
995
996 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
997 ob->command_timeout))
998 {
999 Ustrncpy(buffer, buffer2, sizeof(buffer));
1000 if (errno != 0 || buffer2[0] == 0 ||
1001 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1002 goto RESPONSE_FAILED;
1003 }
1004
1005 /* STARTTLS accepted: try to negotiate a TLS session. */
1006
1007 else
1008 {
1009 int rc = tls_client_start(inblock.sock, host, addrlist,
1010 NULL, /* No DH param */
1011 ob->tls_certificate,
1012 ob->tls_privatekey,
1013 ob->tls_verify_certificates,
1014 ob->tls_crl,
1015 ob->tls_require_ciphers,
1016 ob->command_timeout);
1017
1018 /* TLS negotiation failed; give an error. From outside, this function may
1019 be called again to try in clear on a new connection, if the options permit
1020 it for this host. */
1021
1022 if (rc != OK)
1023 {
1024 save_errno = ERRNO_TLSFAILURE;
1025 message = US"failure while setting up TLS session";
1026 send_quit = FALSE;
1027 goto TLS_FAILED;
1028 }
1029
1030 /* TLS session is set up */
1031
1032 for (addr = addrlist; addr != NULL; addr = addr->next)
1033 {
1034 if (addr->transport_return == PENDING_DEFER)
1035 {
1036 addr->cipher = tls_cipher;
1037 addr->peerdn = tls_peerdn;
1038 }
1039 }
1040 }
1041 }
1042
1043 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. */
1044
1045 if (tls_active >= 0)
1046 {
1047 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n", lmtp? "LHLO" : "EHLO",
1048 helo_data) < 0)
1049 goto SEND_FAILED;
1050 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1051 ob->command_timeout))
1052 goto RESPONSE_FAILED;
1053 }
1054
1055 /* If the host is required to use a secure channel, ensure that we
1056 have one. */
1057
1058 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1059 host->address, NULL) == OK)
1060 {
1061 save_errno = ERRNO_TLSREQUIRED;
1062 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1063 host->name, host->address,
1064 tls_offered? "an attempt to start TLS failed" :
1065 "the server did not offer TLS support");
1066 goto TLS_FAILED;
1067 }
1068 #endif
1069
1070 /* If TLS is active, we have just started it up and re-done the EHLO command,
1071 so its response needs to be analyzed. If TLS is not active and this is a
1072 continued session down a previously-used socket, we haven't just done EHLO, so
1073 we skip this. */
1074
1075 if (continue_hostname == NULL
1076 #ifdef SUPPORT_TLS
1077 || tls_active >= 0
1078 #endif
1079 )
1080 {
1081 int require_auth;
1082 uschar *fail_reason = US"server did not advertise AUTH support";
1083
1084 /* If the response to EHLO specified support for the SIZE parameter, note
1085 this, provided size_addition is non-negative. */
1086
1087 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1088 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1089 PCRE_EOPT, NULL, 0) >= 0;
1090
1091 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1092 the current host, esmtp will be false, so PIPELINING can never be used. */
1093
1094 smtp_use_pipelining = esmtp &&
1095 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1096 PCRE_EOPT, NULL, 0) >= 0;
1097
1098 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1099 smtp_use_pipelining? "" : "not ");
1100
1101 /* Note if the response to EHLO specifies support for the AUTH extension.
1102 If it has, check that this host is one we want to authenticate to, and do
1103 the business. The host name and address must be available when the
1104 authenticator's client driver is running. */
1105
1106 smtp_authenticated = FALSE;
1107 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1108 host->name, host->address, NULL);
1109
1110 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1111 {
1112 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1113 expand_nmax = -1; /* reset */
1114
1115 /* Must not do this check until after we have saved the result of the
1116 regex match above. */
1117
1118 if (require_auth == OK ||
1119 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1120 host->address, NULL) == OK)
1121 {
1122 auth_instance *au;
1123 fail_reason = US"no common mechanisms were found";
1124
1125 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1126
1127 /* Scan the configured authenticators looking for one which is configured
1128 for use as a client and whose name matches an authentication mechanism
1129 supported by the server. If one is found, attempt to authenticate by
1130 calling its client function. */
1131
1132 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1133 {
1134 uschar *p = names;
1135 if (!au->client) continue;
1136
1137 /* Loop to scan supported server mechanisms */
1138
1139 while (*p != 0)
1140 {
1141 int rc;
1142 int len = Ustrlen(au->public_name);
1143 while (isspace(*p)) p++;
1144
1145 if (strncmpic(au->public_name, p, len) != 0 ||
1146 (p[len] != 0 && !isspace(p[len])))
1147 {
1148 while (*p != 0 && !isspace(*p)) p++;
1149 continue;
1150 }
1151
1152 /* Found data for a listed mechanism. Call its client entry. Set
1153 a flag in the outblock so that data is overwritten after sending so
1154 that reflections don't show it. */
1155
1156 fail_reason = US"authentication attempt(s) failed";
1157 outblock.authenticating = TRUE;
1158 rc = (au->info->clientcode)(au, &inblock, &outblock,
1159 ob->command_timeout, buffer, sizeof(buffer));
1160 outblock.authenticating = FALSE;
1161 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1162 au->name, rc);
1163
1164 /* A temporary authentication failure must hold up delivery to
1165 this host. After a permanent authentication failure, we carry on
1166 to try other authentication methods. If all fail hard, try to
1167 deliver the message unauthenticated unless require_auth was set. */
1168
1169 switch(rc)
1170 {
1171 case OK:
1172 smtp_authenticated = TRUE; /* stops the outer loop */
1173 break;
1174
1175 /* Failure after writing a command */
1176
1177 case FAIL_SEND:
1178 goto SEND_FAILED;
1179
1180 /* Failure after reading a response */
1181
1182 case FAIL:
1183 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1184 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1185 au->name, host->name, host->address, buffer);
1186 break;
1187
1188 /* Failure by some other means. In effect, the authenticator
1189 decided it wasn't prepared to handle this case. Typically this
1190 is the result of "fail" in an expansion string. Do we need to
1191 log anything here? */
1192
1193 case CANCELLED:
1194 break;
1195
1196 /* Internal problem, message in buffer. */
1197
1198 case ERROR:
1199 yield = ERROR;
1200 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1201 goto SEND_QUIT;
1202 }
1203
1204 break; /* If not authenticated, try next authenticator */
1205 } /* Loop for scanning supported server mechanisms */
1206 } /* Loop for further authenticators */
1207 }
1208 }
1209
1210 /* If we haven't authenticated, but are required to, give up. */
1211
1212 if (require_auth == OK && !smtp_authenticated)
1213 {
1214 yield = DEFER;
1215 set_errno(addrlist, ERRNO_AUTHFAIL,
1216 string_sprintf("authentication required but %s", fail_reason), DEFER,
1217 FALSE);
1218 goto SEND_QUIT;
1219 }
1220 }
1221
1222 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1223 message-specific. */
1224
1225 setting_up = FALSE;
1226
1227 /* If there is a filter command specified for this transport, we can now
1228 set it up. This cannot be done until the identify of the host is known. */
1229
1230 if (tblock->filter_command != NULL)
1231 {
1232 BOOL rc;
1233 uschar buffer[64];
1234 sprintf(CS buffer, "%.50s transport", tblock->name);
1235 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1236 TRUE, DEFER, addrlist, buffer, NULL);
1237
1238 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1239 yield ERROR. */
1240
1241 if (!rc)
1242 {
1243 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1244 FALSE);
1245 yield = ERROR;
1246 goto SEND_QUIT;
1247 }
1248 }
1249
1250
1251 /* For messages that have more than the maximum number of envelope recipients,
1252 we want to send several transactions down the same SMTP connection. (See
1253 comments in deliver.c as to how this reconciles, heuristically, with
1254 remote_max_parallel.) This optimization was added to Exim after the following
1255 code was already working. The simplest way to put it in without disturbing the
1256 code was to use a goto to jump back to this point when there is another
1257 transaction to handle. */
1258
1259 SEND_MESSAGE:
1260 sync_addr = first_addr;
1261 address_count = 0;
1262 ok = FALSE;
1263 send_rset = TRUE;
1264 completed_address = FALSE;
1265
1266
1267 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1268 qualification, send it, adding something to the message size to allow for
1269 imprecision and things that get added en route. Exim keeps the number of lines
1270 in a message, so we can give an accurate value for the original message, but we
1271 need some additional to handle added headers. (Double "." characters don't get
1272 included in the count.) */
1273
1274 p = buffer;
1275 *p = 0;
1276
1277 if (smtp_use_size)
1278 {
1279 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1280 while (*p) p++;
1281 }
1282
1283 /* Add the authenticated sender address if present */
1284
1285 if (smtp_authenticated && local_authenticated_sender != NULL)
1286 {
1287 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1288 auth_xtextencode(local_authenticated_sender,
1289 Ustrlen(local_authenticated_sender)));
1290 }
1291
1292 /* From here until we send the DATA command, we can make use of PIPELINING
1293 if the server host supports it. The code has to be able to check the responses
1294 at any point, for when the buffer fills up, so we write it totally generally.
1295 When PIPELINING is off, each command written reports that it has flushed the
1296 buffer. */
1297
1298 pending_MAIL = TRUE; /* The block starts with MAIL */
1299
1300 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1301 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1302 mail_command = string_copy(big_buffer); /* Save for later error message */
1303
1304 switch(rc)
1305 {
1306 case -1: /* Transmission error */
1307 goto SEND_FAILED;
1308
1309 case +1: /* Block was sent */
1310 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1311 ob->command_timeout)) goto RESPONSE_FAILED;
1312 pending_MAIL = FALSE;
1313 break;
1314 }
1315
1316 /* Pass over all the relevant recipient addresses for this host, which are the
1317 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1318 several before we have to read the responses for those seen so far. This
1319 checking is done by a subroutine because it also needs to be done at the end.
1320 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1321 the next one if not all are sent.
1322
1323 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1324 last address because we want to abort if any recipients have any kind of
1325 problem, temporary or permanent. We know that all recipient addresses will have
1326 the PENDING_DEFER status, because only one attempt is ever made, and we know
1327 that max_rcpt will be large, so all addresses will be done at once. */
1328
1329 for (addr = first_addr;
1330 address_count < max_rcpt && addr != NULL;
1331 addr = addr->next)
1332 {
1333 int count;
1334 BOOL no_flush;
1335
1336 if (addr->transport_return != PENDING_DEFER) continue;
1337
1338 address_count++;
1339 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1340
1341 /* Now send the RCPT command, and process outstanding responses when
1342 necessary. After a timeout on RCPT, we just end the function, leaving the
1343 yield as OK, because this error can often mean that there is a problem with
1344 just one address, so we don't want to delay the host. */
1345
1346 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>\r\n",
1347 transport_rcpt_address(addr, tblock->rcpt_include_affixes));
1348 if (count < 0) goto SEND_FAILED;
1349 if (count > 0)
1350 {
1351 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1352 &sync_addr, host, count, pending_MAIL, 0, &inblock,
1353 ob->command_timeout, buffer, sizeof(buffer)))
1354 {
1355 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1356 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1357 break;
1358
1359 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1360 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1361 case 0: /* No 2xx or 5xx, but no probs */
1362 break;
1363
1364 case -1: goto END_OFF; /* Timeout on RCPT */
1365 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1366 }
1367 pending_MAIL = FALSE; /* Dealt with MAIL */
1368 }
1369 } /* Loop for next address */
1370
1371 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1372 permanently or temporarily. We should have flushed and synced after the last
1373 RCPT. */
1374
1375 if (mua_wrapper)
1376 {
1377 address_item *badaddr;
1378 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1379 {
1380 if (badaddr->transport_return != PENDING_OK) break;
1381 }
1382 if (badaddr != NULL)
1383 {
1384 set_errno(addrlist, 0, badaddr->message, FAIL,
1385 testflag(badaddr, af_pass_message));
1386 ok = FALSE;
1387 }
1388 }
1389
1390 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1391 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1392 have a good recipient buffered up if we are pipelining. We don't want to waste
1393 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1394 are pipelining. The responses are all handled by sync_responses(). */
1395
1396 if (ok || (smtp_use_pipelining && !mua_wrapper))
1397 {
1398 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1399 if (count < 0) goto SEND_FAILED;
1400 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1401 host, count, pending_MAIL, ok? +1 : -1, &inblock,
1402 ob->command_timeout, buffer, sizeof(buffer)))
1403 {
1404 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1405 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1406 break;
1407
1408 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1409 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1410 case 0: break; /* No 2xx or 5xx, but no probs */
1411
1412 case -1: goto END_OFF; /* Timeout on RCPT */
1413 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1414 }
1415 }
1416
1417 /* Save the first address of the next batch. */
1418
1419 first_addr = addr;
1420
1421 /* If there were no good recipients (but otherwise there have been no
1422 problems), just set ok TRUE, since we have handled address-specific errors
1423 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1424 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1425 well as body. Set the appropriate timeout value to be used for each chunk.
1426 (Haven't been able to make it work using select() for writing yet.) */
1427
1428 if (!ok) ok = TRUE; else
1429 {
1430 sigalrm_seen = FALSE;
1431 transport_write_timeout = ob->data_timeout;
1432 smtp_command = US"sending data block"; /* For error messages */
1433 DEBUG(D_transport|D_v)
1434 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1435 transport_count = 0;
1436 #ifdef EXPERIMENTAL_DOMAINKEYS
1437 if ( (ob->dk_private_key != NULL) && (ob->dk_selector != NULL) )
1438 ok = dk_transport_write_message(addrlist, inblock.sock,
1439 topt_use_crlf | topt_end_dot | topt_escape_headers |
1440 (tblock->body_only? topt_no_headers : 0) |
1441 (tblock->headers_only? topt_no_body : 0) |
1442 (tblock->return_path_add? topt_add_return_path : 0) |
1443 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1444 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1445 0, /* No size limit */
1446 tblock->add_headers, tblock->remove_headers,
1447 US".", US"..", /* Escaping strings */
1448 tblock->rewrite_rules, tblock->rewrite_existflags,
1449 ob->dk_private_key, ob->dk_domain, ob->dk_selector,
1450 ob->dk_canon, ob->dk_headers, ob->dk_strict);
1451 else
1452 #endif
1453 ok = transport_write_message(addrlist, inblock.sock,
1454 topt_use_crlf | topt_end_dot | topt_escape_headers |
1455 (tblock->body_only? topt_no_headers : 0) |
1456 (tblock->headers_only? topt_no_body : 0) |
1457 (tblock->return_path_add? topt_add_return_path : 0) |
1458 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1459 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1460 0, /* No size limit */
1461 tblock->add_headers, tblock->remove_headers,
1462 US".", US"..", /* Escaping strings */
1463 tblock->rewrite_rules, tblock->rewrite_existflags);
1464
1465 /* transport_write_message() uses write() because it is called from other
1466 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1467 it can exit with "Broken pipe" as its error. This really means that the
1468 socket got closed at the far end. */
1469
1470 transport_write_timeout = 0; /* for subsequent transports */
1471
1472 /* Failure can either be some kind of I/O disaster (including timeout),
1473 or the failure of a transport filter or the expansion of added headers. */
1474
1475 if (!ok)
1476 {
1477 buffer[0] = 0; /* There hasn't been a response */
1478 goto RESPONSE_FAILED;
1479 }
1480
1481 /* We used to send the terminating "." explicitly here, but because of
1482 buffering effects at both ends of TCP/IP connections, you don't gain
1483 anything by keeping it separate, so it might as well go in the final
1484 data buffer for efficiency. This is now done by setting the topt_end_dot
1485 flag above. */
1486
1487 smtp_command = US"end of data";
1488
1489 /* For SMTP, we now read a single response that applies to the whole message.
1490 If it is OK, then all the addresses have been delivered. */
1491
1492 if (!lmtp) ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1493 ob->final_timeout);
1494
1495 /* For LMTP, we get back a response for every RCPT command that we sent;
1496 some may be accepted and some rejected. For those that get a response, their
1497 status is fixed; any that are accepted have been handed over, even if later
1498 responses crash - at least, that's how I read RFC 2033.
1499
1500 If all went well, mark the recipient addresses as completed, record which
1501 host/IPaddress they were delivered to, and cut out RSET when sending another
1502 message down the same channel. Write the completed addresses to the journal
1503 now so that they are recorded in case there is a crash of hardware or
1504 software before the spool gets updated. Also record the final SMTP
1505 confirmation if needed (for SMTP only). */
1506
1507 if (ok)
1508 {
1509 int flag = '=';
1510 int delivery_time = (int)(time(NULL) - start_delivery_time);
1511 int len;
1512 host_item *thost;
1513 uschar *conf = NULL;
1514 send_rset = FALSE;
1515
1516 /* Make a copy of the host if it is local to this invocation
1517 of the transport. */
1518
1519 if (copy_host)
1520 {
1521 thost = store_get(sizeof(host_item));
1522 *thost = *host;
1523 thost->name = string_copy(host->name);
1524 thost->address = string_copy(host->address);
1525 }
1526 else thost = host;
1527
1528 /* Set up confirmation if needed - applies only to SMTP */
1529
1530 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1531 {
1532 uschar *s = string_printing(buffer);
1533 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1534 }
1535
1536 /* Process all transported addresses - for LMTP, read a status for
1537 each one. */
1538
1539 for (addr = addrlist; addr != first_addr; addr = addr->next)
1540 {
1541 if (addr->transport_return != PENDING_OK) continue;
1542
1543 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1544 remaining addresses. Otherwise, it's a return code for just the one
1545 address. */
1546
1547 if (lmtp)
1548 {
1549 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1550 ob->final_timeout))
1551 {
1552 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1553 addr->message = string_sprintf("LMTP error after %s: %s",
1554 big_buffer, string_printing(buffer));
1555 addr->transport_return = (buffer[0] == '5')? FAIL : DEFER;
1556 continue;
1557 }
1558 completed_address = TRUE; /* NOW we can set this flag */
1559 }
1560
1561 /* SMTP, or success return from LMTP for this address. Pass back the
1562 actual port used. */
1563
1564 addr->transport_return = OK;
1565 addr->more_errno = delivery_time;
1566 thost->port = port;
1567 addr->host_used = thost;
1568 addr->special_action = flag;
1569 addr->message = conf;
1570 flag = '-';
1571
1572 /* Update the journal. For homonymic addresses, use the base address plus
1573 the transport name. See lots of comments in deliver.c about the reasons
1574 for the complications when homonyms are involved. Just carry on after
1575 write error, as it may prove possible to update the spool file later. */
1576
1577 if (testflag(addr, af_homonym))
1578 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1579 else
1580 sprintf(CS buffer, "%.500s\n", addr->unique);
1581
1582 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1583 len = Ustrlen(CS buffer);
1584 if (write(journal_fd, buffer, len) != len)
1585 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1586 "%s: %s", buffer, strerror(errno));
1587 }
1588
1589 /* Ensure the journal file is pushed out to disk. */
1590
1591 if (fsync(journal_fd) < 0)
1592 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1593 strerror(errno));
1594 }
1595 }
1596
1597
1598 /* Handle general (not specific to one address) failures here. The value of ok
1599 is used to skip over this code on the falling through case. A timeout causes a
1600 deferral. Other errors may defer or fail according to the response code, and
1601 may set up a special errno value, e.g. after connection chopped, which is
1602 assumed if errno == 0 and there is no text in the buffer. If control reaches
1603 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1604 the problem is not related to this specific message. */
1605
1606 if (!ok)
1607 {
1608 int code;
1609
1610 RESPONSE_FAILED:
1611 save_errno = errno;
1612 message = NULL;
1613 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1614 buffer, &code, &message, &pass_message);
1615 goto FAILED;
1616
1617 SEND_FAILED:
1618 save_errno = errno;
1619 code = '4';
1620 message = US string_sprintf("send() to %s [%s] failed: %s",
1621 host->name, host->address, strerror(save_errno));
1622 send_quit = FALSE;
1623 goto FAILED;
1624
1625 /* This label is jumped to directly when a TLS negotiation has failed,
1626 or was not done for a host for which it is required. Values will be set
1627 in message and save_errno, and setting_up will always be true. Treat as
1628 a temporary error. */
1629
1630 #ifdef SUPPORT_TLS
1631 TLS_FAILED:
1632 code = '4';
1633 #endif
1634
1635 /* If the failure happened while setting up the call, see if the failure was
1636 a 5xx response (this will either be on connection, or following HELO - a 5xx
1637 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1638 never going to accept them. For other errors during setting up (timeouts or
1639 whatever), defer all addresses, and yield DEFER, so that the host is not
1640 tried again for a while. */
1641
1642 FAILED:
1643 ok = FALSE; /* For when reached by GOTO */
1644
1645 if (setting_up)
1646 {
1647 if (code == '5')
1648 {
1649 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1650 }
1651 else
1652 {
1653 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1654 yield = DEFER;
1655 }
1656 }
1657
1658 /* If there was an I/O error or timeout or other transportation error,
1659 indicated by errno being non-zero, defer all addresses and yield DEFER,
1660 except for the case of failed add_headers expansion, or a transport filter
1661 failure, when the yield should be ERROR, to stop it trying other hosts.
1662
1663 However, handle timeouts after MAIL FROM or "." and loss of connection after
1664 "." specially. They can indicate a problem with the sender address or with
1665 the contents of the message rather than a real error on the connection.
1666 Therefore, treat these cases in the same way as a 4xx response.
1667
1668 The following condition tests for NOT these special cases. */
1669
1670 else if (save_errno != 0 &&
1671 (save_errno != ETIMEDOUT ||
1672 (Ustrncmp(smtp_command,"MAIL",4) != 0 &&
1673 Ustrncmp(smtp_command,"end ",4) != 0)) &&
1674 (save_errno != ERRNO_SMTPCLOSED ||
1675 Ustrncmp(smtp_command,"end ",4) != 0))
1676 {
1677 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1678 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1679 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1680 }
1681
1682 /* Otherwise we have a message-specific error response from the remote
1683 host. This is one of
1684 (a) negative response or timeout after "mail from"
1685 (b) negative response after "data"
1686 (c) negative response or timeout or dropped connection after "."
1687 It won't be a negative response or timeout after "rcpt to", as that is dealt
1688 with separately above. The action in all cases is to set an appropriate
1689 error code for all the addresses, but to leave yield set to OK because
1690 the host itself has not failed. [It might in practice have failed for a
1691 timeout after MAIL FROM, or "." but if so, we'll discover that at the next
1692 delivery attempt.] For a temporary error, set the message_defer flag, and
1693 write to the logs for information if this is not the last host. The error for
1694 the last host will be logged as part of the address's log line. */
1695
1696 else
1697 {
1698 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1699
1700 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1701 pass_message);
1702
1703 /* If there's an errno, the message contains just the identity of
1704 the host. */
1705
1706 if (code != '5') /* Anything other than 5 is treated as temporary */
1707 {
1708 if (save_errno > 0)
1709 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1710 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1711 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1712 *message_defer = TRUE;
1713 }
1714 }
1715 }
1716
1717
1718 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1719 SMTP session tidily. However, if there were too many addresses to send in one
1720 message (indicated by first_addr being non-NULL) we want to carry on with the
1721 rest of them. Also, it is desirable to send more than one message down the SMTP
1722 connection if there are several waiting, provided we haven't already sent so
1723 many as to hit the configured limit. The function transport_check_waiting looks
1724 for a waiting message and returns its id. Then transport_pass_socket tries to
1725 set up a continued delivery by passing the socket on to another process. The
1726 variable send_rset is FALSE if a message has just been successfully transfered.
1727
1728 If we are already sending down a continued channel, there may be further
1729 addresses not yet delivered that are aimed at the same host, but which have not
1730 been passed in this run of the transport. In this case, continue_more will be
1731 true, and all we should do is send RSET if necessary, and return, leaving the
1732 channel open.
1733
1734 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1735 do not want to continue with other messages down the same channel, because that
1736 can lead to looping between two or more messages, all with the same,
1737 temporarily failing address(es). [The retry information isn't updated yet, so
1738 new processes keep on trying.] We probably also don't want to try more of this
1739 message's addresses either.
1740
1741 If we have started a TLS session, we have to end it before passing the
1742 connection to a new process. However, not all servers can handle this (Exim
1743 can), so we do not pass such a connection on if the host matches
1744 hosts_nopass_tls. */
1745
1746 DEBUG(D_transport)
1747 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1748 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1749 continue_more, yield, (first_addr == NULL)? "":"not ");
1750
1751 if (completed_address && ok && send_quit)
1752 {
1753 BOOL more;
1754 if (first_addr != NULL || continue_more ||
1755 (
1756 (tls_active < 0 ||
1757 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
1758 host->address, NULL) != OK)
1759 &&
1760 transport_check_waiting(tblock->name, host->name,
1761 tblock->connection_max_messages, new_message_id, &more)
1762 ))
1763 {
1764 uschar *msg;
1765 BOOL pass_message;
1766
1767 if (send_rset)
1768 {
1769 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
1770 {
1771 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
1772 host->address, strerror(save_errno));
1773 send_quit = FALSE;
1774 }
1775 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1776 ob->command_timeout)))
1777 {
1778 int code;
1779 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
1780 &pass_message);
1781 if (!send_quit)
1782 {
1783 DEBUG(D_transport) debug_printf("%s\n", msg);
1784 }
1785 }
1786 }
1787
1788 /* Either RSET was not needed, or it succeeded */
1789
1790 if (ok)
1791 {
1792 if (first_addr != NULL) /* More addresses still to be sent */
1793 { /* in this run of the transport */
1794 continue_sequence++; /* Causes * in logging */
1795 goto SEND_MESSAGE;
1796 }
1797 if (continue_more) return yield; /* More addresses for another run */
1798
1799 /* Pass the socket to a new Exim process. Before doing so, we must shut
1800 down TLS. Not all MTAs allow for the continuation of the SMTP session
1801 when TLS is shut down. We test for this by sending a new EHLO. If we
1802 don't get a good response, we don't attempt to pass the socket on. */
1803
1804 #ifdef SUPPORT_TLS
1805 if (tls_active >= 0)
1806 {
1807 tls_close(TRUE);
1808 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
1809 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1810 ob->command_timeout);
1811 }
1812 #endif
1813
1814 /* If the socket is successfully passed, we musn't send QUIT (or
1815 indeed anything!) from here. */
1816
1817 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
1818 new_message_id, inblock.sock))
1819 {
1820 send_quit = FALSE;
1821 }
1822 }
1823
1824 /* If RSET failed and there are addresses left, they get deferred. */
1825
1826 else set_errno(first_addr, errno, msg, DEFER, FALSE);
1827 }
1828 }
1829
1830 /* End off tidily with QUIT unless the connection has died or the socket has
1831 been passed to another process. There has been discussion on the net about what
1832 to do after sending QUIT. The wording of the RFC suggests that it is necessary
1833 to wait for a response, but on the other hand, there isn't anything one can do
1834 with an error response, other than log it. Exim used to do that. However,
1835 further discussion suggested that it is positively advantageous not to wait for
1836 the response, but to close the session immediately. This is supposed to move
1837 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
1838 load from the server. (Hosts that are both servers and clients may not see much
1839 difference, of course.) Further discussion indicated that this was safe to do
1840 on Unix systems which have decent implementations of TCP/IP that leave the
1841 connection around for a while (TIME_WAIT) after the application has gone away.
1842 This enables the response sent by the server to be properly ACKed rather than
1843 timed out, as can happen on broken TCP/IP implementations on other OS.
1844
1845 This change is being made on 31-Jul-98. After over a year of trouble-free
1846 operation, the old commented-out code was removed on 17-Sep-99. */
1847
1848 SEND_QUIT:
1849 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
1850
1851 END_OFF:
1852
1853 #ifdef SUPPORT_TLS
1854 tls_close(TRUE);
1855 #endif
1856
1857 /* Close the socket, and return the appropriate value, first setting
1858 continue_transport and continue_hostname NULL to prevent any other addresses
1859 that may include the host from trying to re-use a continuation socket. This
1860 works because the NULL setting is passed back to the calling process, and
1861 remote_max_parallel is forced to 1 when delivering over an existing connection,
1862
1863 If all went well and continue_more is set, we shouldn't actually get here if
1864 there are further addresses, as the return above will be taken. However,
1865 writing RSET might have failed, or there may be other addresses whose hosts are
1866 specified in the transports, and therefore not visible at top level, in which
1867 case continue_more won't get set. */
1868
1869 close(inblock.sock);
1870 continue_transport = NULL;
1871 continue_hostname = NULL;
1872 return yield;
1873 }
1874
1875
1876
1877
1878 /*************************************************
1879 * Closedown entry point *
1880 *************************************************/
1881
1882 /* This function is called when exim is passed an open smtp channel
1883 from another incarnation, but the message which it has been asked
1884 to deliver no longer exists. The channel is on stdin.
1885
1886 We might do fancy things like looking for another message to send down
1887 the channel, but if the one we sought has gone, it has probably been
1888 delivered by some other process that itself will seek further messages,
1889 so just close down our connection.
1890
1891 Argument: pointer to the transport instance block
1892 Returns: nothing
1893 */
1894
1895 void
1896 smtp_transport_closedown(transport_instance *tblock)
1897 {
1898 smtp_transport_options_block *ob =
1899 (smtp_transport_options_block *)(tblock->options_block);
1900 smtp_inblock inblock;
1901 smtp_outblock outblock;
1902 uschar buffer[256];
1903 uschar inbuffer[4096];
1904 uschar outbuffer[16];
1905
1906 inblock.sock = fileno(stdin);
1907 inblock.buffer = inbuffer;
1908 inblock.buffersize = sizeof(inbuffer);
1909 inblock.ptr = inbuffer;
1910 inblock.ptrend = inbuffer;
1911
1912 outblock.sock = inblock.sock;
1913 outblock.buffersize = sizeof(outbuffer);
1914 outblock.buffer = outbuffer;
1915 outblock.ptr = outbuffer;
1916 outblock.cmd_count = 0;
1917 outblock.authenticating = FALSE;
1918
1919 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
1920 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1921 ob->command_timeout);
1922 close(inblock.sock);
1923 }
1924
1925
1926
1927 /*************************************************
1928 * Prepare addresses for delivery *
1929 *************************************************/
1930
1931 /* This function is called to flush out error settings from previous delivery
1932 attempts to other hosts. It also records whether we got here via an MX record
1933 or not in the more_errno field of the address. We are interested only in
1934 addresses that are still marked DEFER - others may have got delivered to a
1935 previously considered IP address. Set their status to PENDING_DEFER to indicate
1936 which ones are relevant this time.
1937
1938 Arguments:
1939 addrlist the list of addresses
1940 host the host we are delivering to
1941
1942 Returns: the first address for this delivery
1943 */
1944
1945 static address_item *
1946 prepare_addresses(address_item *addrlist, host_item *host)
1947 {
1948 address_item *first_addr = NULL;
1949 address_item *addr;
1950 for (addr = addrlist; addr != NULL; addr = addr->next)
1951 {
1952 if (addr->transport_return != DEFER) continue;
1953 if (first_addr == NULL) first_addr = addr;
1954 addr->transport_return = PENDING_DEFER;
1955 addr->basic_errno = 0;
1956 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
1957 addr->message = NULL;
1958 #ifdef SUPPORT_TLS
1959 addr->cipher = NULL;
1960 addr->peerdn = NULL;
1961 #endif
1962 }
1963 return first_addr;
1964 }
1965
1966
1967
1968 /*************************************************
1969 * Main entry point *
1970 *************************************************/
1971
1972 /* See local README for interface details. As this is a remote transport, it is
1973 given a chain of addresses to be delivered in one connection, if possible. It
1974 always returns TRUE, indicating that each address has its own independent
1975 status set, except if there is a setting up problem, in which case it returns
1976 FALSE. */
1977
1978 BOOL
1979 smtp_transport_entry(
1980 transport_instance *tblock, /* data for this instantiation */
1981 address_item *addrlist) /* addresses we are working on */
1982 {
1983 int cutoff_retry;
1984 int port;
1985 int hosts_defer = 0;
1986 int hosts_fail = 0;
1987 int hosts_looked_up = 0;
1988 int hosts_retry = 0;
1989 int hosts_serial = 0;
1990 int hosts_total = 0;
1991 int total_hosts_tried = 0;
1992 address_item *addr;
1993 BOOL expired = TRUE;
1994 BOOL continuing = continue_hostname != NULL;
1995 uschar *expanded_hosts = NULL;
1996 uschar *pistring;
1997 uschar *tid = string_sprintf("%s transport", tblock->name);
1998 smtp_transport_options_block *ob =
1999 (smtp_transport_options_block *)(tblock->options_block);
2000 host_item *hostlist = addrlist->host_list;
2001 host_item *host = NULL;
2002
2003 DEBUG(D_transport)
2004 {
2005 debug_printf("%s transport entered\n", tblock->name);
2006 for (addr = addrlist; addr != NULL; addr = addr->next)
2007 debug_printf(" %s\n", addr->address);
2008 if (continuing) debug_printf("already connected to %s [%s]\n",
2009 continue_hostname, continue_host_address);
2010 }
2011
2012 /* If a host list is not defined for the addresses - they must all have the
2013 same one in order to be passed to a single transport - or if the transport has
2014 a host list with hosts_override set, use the host list supplied with the
2015 transport. It is an error for this not to exist. */
2016
2017 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2018 {
2019 if (ob->hosts == NULL)
2020 {
2021 addrlist->message = string_sprintf("%s transport called with no hosts set",
2022 tblock->name);
2023 addrlist->transport_return = PANIC;
2024 return FALSE; /* Only top address has status */
2025 }
2026
2027 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2028 ob->hosts);
2029
2030 /* If the transport's host list contains no '$' characters, and we are not
2031 randomizing, it is fixed and therefore a chain of hosts can be built once
2032 and for all, and remembered for subsequent use by other calls to this
2033 transport. If, on the other hand, the host list does contain '$', or we are
2034 randomizing its order, we have to rebuild it each time. In the fixed case,
2035 as the hosts string will never be used again, it doesn't matter that we
2036 replace all the : characters with zeros. */
2037
2038 if (ob->hostlist == NULL)
2039 {
2040 uschar *s = ob->hosts;
2041
2042 if (Ustrchr(s, '$') != NULL)
2043 {
2044 expanded_hosts = expand_string(s);
2045 if (expanded_hosts == NULL)
2046 {
2047 addrlist->message = string_sprintf("failed to expand list of hosts "
2048 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2049 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2050 return FALSE; /* Only top address has status */
2051 }
2052 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2053 "\"%s\"\n", s, expanded_hosts);
2054 s = expanded_hosts;
2055 }
2056 else
2057 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2058
2059 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2060
2061 /* If there was no expansion of hosts, save the host list for
2062 next time. */
2063
2064 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2065 }
2066
2067 /* This is not the first time this transport has been run in this delivery;
2068 the host list was built previously. */
2069
2070 else hostlist = ob->hostlist;
2071 }
2072
2073 /* The host list was supplied with the address. If hosts_randomize is set, we
2074 must sort it into a random order if it did not come from MX records and has not
2075 already been randomized (but don't bother if continuing down an existing
2076 connection). */
2077
2078 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2079 {
2080 host_item *newlist = NULL;
2081 while (hostlist != NULL)
2082 {
2083 host_item *h = hostlist;
2084 hostlist = hostlist->next;
2085
2086 h->sort_key = random_number(100);
2087
2088 if (newlist == NULL)
2089 {
2090 h->next = NULL;
2091 newlist = h;
2092 }
2093 else if (h->sort_key < newlist->sort_key)
2094 {
2095 h->next = newlist;
2096 newlist = h;
2097 }
2098 else
2099 {
2100 host_item *hh = newlist;
2101 while (hh->next != NULL)
2102 {
2103 if (h->sort_key < hh->next->sort_key) break;
2104 hh = hh->next;
2105 }
2106 h->next = hh->next;
2107 hh->next = h;
2108 }
2109 }
2110
2111 hostlist = addrlist->host_list = newlist;
2112 }
2113
2114
2115 /* Sort out the port. Set up a string for adding to the retry key if the port
2116 number is not the standard SMTP port. */
2117
2118 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2119 pistring = string_sprintf(":%d", port);
2120 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2121
2122
2123 /* For each host-plus-IP-address on the list:
2124
2125 . If this is a continued delivery and the host isn't the one with the
2126 current connection, skip.
2127
2128 . If the status is unusable (i.e. previously failed or retry checked), skip.
2129
2130 . If no IP address set, get the address, either by turning the name into
2131 an address, calling gethostbyname if gethostbyname is on, or by calling
2132 the DNS. The DNS may yield multiple addresses, in which case insert the
2133 extra ones into the list.
2134
2135 . Get the retry data if not previously obtained for this address and set the
2136 field which remembers the state of this address. Skip if the retry time is
2137 not reached. If not, remember whether retry data was found. The retry string
2138 contains both the name and the IP address.
2139
2140 . Scan the list of addresses and mark those whose status is DEFER as
2141 PENDING_DEFER. These are the only ones that will be processed in this cycle
2142 of the hosts loop.
2143
2144 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2145 Some addresses may be successfully delivered, others may fail, and yet
2146 others may get temporary errors and so get marked DEFER.
2147
2148 . The return from the delivery attempt is OK if a connection was made and a
2149 valid SMTP dialogue was completed. Otherwise it is DEFER.
2150
2151 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2152
2153 . If fail to connect, or other defer state, add a retry item.
2154
2155 . If there are any addresses whose status is still DEFER, carry on to the
2156 next host/IPaddress, unless we have tried the number of hosts given
2157 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2158 there is some fancy logic for hosts_max_try that means its limit can be
2159 overstepped in some circumstances.
2160
2161 If we get to the end of the list, all hosts have deferred at least one address,
2162 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2163 delivery attempt to those hosts whose last try was before the arrival time of
2164 the current message. To cope with this, we have to go round the loop a second
2165 time. After that, set the status and error data for any addresses that haven't
2166 had it set already. */
2167
2168 for (cutoff_retry = 0; expired &&
2169 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2170 cutoff_retry++)
2171 {
2172 host_item *nexthost = NULL;
2173 int unexpired_hosts_tried = 0;
2174
2175 for (host = hostlist;
2176 host != NULL &&
2177 unexpired_hosts_tried < ob->hosts_max_try &&
2178 total_hosts_tried < ob->hosts_max_try_hardlimit;
2179 host = nexthost)
2180 {
2181 int rc;
2182 int host_af;
2183 uschar *rs;
2184 BOOL serialized = FALSE;
2185 BOOL host_is_expired = FALSE;
2186 BOOL message_defer = FALSE;
2187 BOOL ifchanges = FALSE;
2188 BOOL some_deferred = FALSE;
2189 address_item *first_addr = NULL;
2190 uschar *interface = NULL;
2191 uschar *retry_host_key = NULL;
2192 uschar *retry_message_key = NULL;
2193 uschar *serialize_key = NULL;
2194
2195 /* Default next host is next host. :-) But this can vary if the
2196 hosts_max_try limit is hit (see below). It may also be reset if a host
2197 address is looked up here (in case the host was multihomed). */
2198
2199 nexthost = host->next;
2200
2201 /* Set the flag requesting that this host be added to the waiting
2202 database if the delivery fails temporarily or if we are running with
2203 queue_smtp or a 2-stage queue run. This gets unset for certain
2204 kinds of error, typically those that are specific to the message. */
2205
2206 host->update_waiting = TRUE;
2207
2208 /* If the address hasn't yet been obtained from the host name, look it up
2209 now, unless the host is already marked as unusable. If it is marked as
2210 unusable, it means that the router was unable to find its IP address (in
2211 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2212 the lookup failed last time. We don't get this far if *all* MX records
2213 point to non-existent hosts; that is treated as a hard error.
2214
2215 We can just skip this host entirely. When the hosts came from the router,
2216 the address will timeout based on the other host(s); when the address is
2217 looked up below, there is an explicit retry record added.
2218
2219 Note that we mustn't skip unusable hosts if the address is not unset; they
2220 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2221
2222 if (host->address == NULL)
2223 {
2224 uschar *canonical_name;
2225
2226 if (host->status >= hstatus_unusable)
2227 {
2228 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2229 host->name);
2230 continue;
2231 }
2232
2233 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2234
2235 hosts_looked_up++;
2236
2237 /* Find by name if so configured, or if it's an IP address. We don't
2238 just copy the IP address, because we need the test-for-local to happen. */
2239
2240 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) > 0)
2241 rc = host_find_byname(host, NULL, &canonical_name, TRUE);
2242 else
2243 {
2244 int flags = HOST_FIND_BY_A;
2245 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2246 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2247 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2248 &canonical_name, NULL);
2249 }
2250
2251 /* Failure to find the host at this time (usually DNS temporary failure)
2252 is really a kind of routing failure rather than a transport failure.
2253 Therefore we add a retry item of the routing kind, not to stop us trying
2254 to look this name up here again, but to ensure the address gets timed
2255 out if the failures go on long enough. A complete failure at this point
2256 commonly points to a configuration error, but the best action is still
2257 to carry on for the next host. */
2258
2259 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2260 {
2261 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2262 expired = FALSE;
2263 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2264 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2265 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2266 host->status = hstatus_unusable;
2267
2268 for (addr = addrlist; addr != NULL; addr = addr->next)
2269 {
2270 if (addr->transport_return != DEFER) continue;
2271 addr->basic_errno = ERRNO_UNKNOWNHOST;
2272 addr->message =
2273 string_sprintf("failed to lookup IP address for %s", host->name);
2274 }
2275 continue;
2276 }
2277
2278 /* If the host is actually the local host, we may have a problem, or
2279 there may be some cunning configuration going on. In the problem case,
2280 log things and give up. The default transport status is already DEFER. */
2281
2282 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2283 {
2284 for (addr = addrlist; addr != NULL; addr = addr->next)
2285 {
2286 addr->basic_errno = 0;
2287 addr->message = string_sprintf("%s transport found host %s to be "
2288 "local", tblock->name, host->name);
2289 }
2290 goto END_TRANSPORT;
2291 }
2292 } /* End of block for IP address lookup */
2293
2294 /* If this is a continued delivery, we are interested only in the host
2295 which matches the name of the existing open channel. The check is put
2296 here after the local host lookup, in case the name gets expanded as a
2297 result of the lookup. Set expired FALSE, to save the outer loop executing
2298 twice. */
2299
2300 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2301 Ustrcmp(continue_host_address, host->address) != 0))
2302 {
2303 expired = FALSE;
2304 continue; /* With next host */
2305 }
2306
2307 /* Reset the default next host in case a multihomed host whose addresses
2308 are not looked up till just above added to the host list. */
2309
2310 nexthost = host->next;
2311
2312 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2313 domain is in queue_smtp_domains, we don't actually want to attempt any
2314 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2315 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2316 were not in it. We don't want to hold up all SMTP deliveries! Except when
2317 doing a two-stage queue run, don't do this if forcing. */
2318
2319 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2320 match_isinlist(addrlist->domain, &queue_smtp_domains, 0, NULL, NULL,
2321 MCL_DOMAIN, TRUE, NULL) == OK))
2322 {
2323 expired = FALSE;
2324 for (addr = addrlist; addr != NULL; addr = addr->next)
2325 {
2326 if (addr->transport_return != DEFER) continue;
2327 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2328 }
2329 continue; /* With next host */
2330 }
2331
2332 /* Count hosts being considered - purely for an intelligent comment
2333 if none are usable. */
2334
2335 hosts_total++;
2336
2337 /* Set $host and $host address now in case they are needed for the
2338 interface expansion or the serialize_hosts check; they remain set if an
2339 actual delivery happens. */
2340
2341 deliver_host = host->name;
2342 deliver_host_address = host->address;
2343
2344 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2345 string changes upon expansion, we must add it to the key that is used for
2346 retries, because connections to the same host from a different interface
2347 should be treated separately. */
2348
2349 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2350 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2351 &interface, tid))
2352 return FALSE;
2353 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2354
2355 /* The first time round the outer loop, check the status of the host by
2356 inspecting the retry data. The second time round, we are interested only
2357 in expired hosts that haven't been tried since this message arrived. */
2358
2359 if (cutoff_retry == 0)
2360 {
2361 /* Ensure the status of the address is set by checking retry data if
2362 necessary. There maybe host-specific retry data (applicable to all
2363 messages) and also data for retries of a specific message at this host.
2364 If either of these retry records are actually read, the keys used are
2365 returned to save recomputing them later. */
2366
2367 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2368 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2369
2370 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2371 (host->address == NULL)? US"" : host->address, pistring,
2372 (host->status == hstatus_usable)? "usable" :
2373 (host->status == hstatus_unusable)? "unusable" :
2374 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2375
2376 /* Skip this address if not usable at this time, noting if it wasn't
2377 actually expired, both locally and in the address. */
2378
2379 switch (host->status)
2380 {
2381 case hstatus_unusable:
2382 expired = FALSE;
2383 setflag(addrlist, af_retry_skipped);
2384 /* Fall through */
2385
2386 case hstatus_unusable_expired:
2387 switch (host->why)
2388 {
2389 case hwhy_retry: hosts_retry++; break;
2390 case hwhy_failed: hosts_fail++; break;
2391 case hwhy_deferred: hosts_defer++; break;
2392 }
2393
2394 /* If there was a retry message key, implying that previously there
2395 was a message-specific defer, we don't want to update the list of
2396 messages waiting for this host. */
2397
2398 if (retry_message_key != NULL) host->update_waiting = FALSE;
2399 continue; /* With the next host or IP address */
2400 }
2401 }
2402
2403 /* Second time round the loop: if the address is set but expired, and
2404 the message is newer than the last try, let it through. */
2405
2406 else
2407 {
2408 if (host->address == NULL ||
2409 host->status != hstatus_unusable_expired ||
2410 host->last_try > received_time)
2411 continue;
2412 DEBUG(D_transport)
2413 debug_printf("trying expired host %s [%s]%s\n",
2414 host->name, host->address, pistring);
2415 host_is_expired = TRUE;
2416 }
2417
2418 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2419 it remains TRUE only if all hosts are expired and none are actually tried.
2420 */
2421
2422 expired = FALSE;
2423
2424 /* If this host is listed as one to which access must be serialized,
2425 see if another Exim process has a connection to it, and if so, skip
2426 this host. If not, update the database to record our connection to it
2427 and remember this for later deletion. Do not do any of this if we are
2428 sending the message down a pre-existing connection. */
2429
2430 if (!continuing &&
2431 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2432 host->address, NULL) == OK)
2433 {
2434 serialize_key = string_sprintf("host-serialize-%s", host->name);
2435 if (!enq_start(serialize_key))
2436 {
2437 DEBUG(D_transport)
2438 debug_printf("skipping host %s because another Exim process "
2439 "is connected to it\n", host->name);
2440 hosts_serial++;
2441 continue;
2442 }
2443 serialized = TRUE;
2444 }
2445
2446 /* OK, we have an IP address that is not waiting for its retry time to
2447 arrive (it might be expired) OR (second time round the loop) we have an
2448 expired host that hasn't been tried since the message arrived. Have a go
2449 at delivering the message to it. First prepare the addresses by flushing
2450 out the result of previous attempts, and finding the first address that
2451 is still to be delivered. */
2452
2453 first_addr = prepare_addresses(addrlist, host);
2454
2455 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2456 message_id, host->name, host->address, addrlist->address,
2457 (addrlist->next == NULL)? "" : ", ...");
2458
2459 set_process_info("delivering %s to %s [%s] (%s%s)",
2460 message_id, host->name, host->address, addrlist->address,
2461 (addrlist->next == NULL)? "" : ", ...");
2462
2463 /* This is not for real; don't do the delivery. If there are
2464 any remaining hosts, list them. */
2465
2466 if (dont_deliver)
2467 {
2468 host_item *host2;
2469 set_errno(addrlist, 0, NULL, OK, FALSE);
2470 for (addr = addrlist; addr != NULL; addr = addr->next)
2471 {
2472 addr->host_used = host;
2473 addr->special_action = '*';
2474 addr->message = US"delivery bypassed by -N option";
2475 }
2476 DEBUG(D_transport)
2477 {
2478 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2479 "*** host and remaining hosts:\n", tblock->name);
2480 for (host2 = host; host2 != NULL; host2 = host2->next)
2481 debug_printf(" %s [%s]\n", host2->name,
2482 (host2->address == NULL)? US"unset" : host2->address);
2483 }
2484 rc = OK;
2485 }
2486
2487 /* This is for real. If the host is expired, we don't count it for
2488 hosts_max_retry. This ensures that all hosts must expire before an address
2489 is timed out, unless hosts_max_try_hardlimit (which protects against
2490 lunatic DNS configurations) is reached.
2491
2492 If the host is not expired and we are about to hit the hosts_max_retry
2493 limit, check to see if there is a subsequent hosts with a different MX
2494 value. If so, make that the next host, and don't count this one. This is a
2495 heuristic to make sure that different MXs do get tried. With a normal kind
2496 of retry rule, they would get tried anyway when the earlier hosts were
2497 delayed, but if the domain has a "retry every time" type of rule - as is
2498 often used for the the very large ISPs, that won't happen. */
2499
2500 else
2501 {
2502 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2503 {
2504 host_item *h;
2505 DEBUG(D_transport)
2506 debug_printf("hosts_max_try limit reached with this host\n");
2507 for (h = host; h != NULL; h = h->next)
2508 if (h->mx != host->mx) break;
2509 if (h != NULL)
2510 {
2511 nexthost = h;
2512 unexpired_hosts_tried--;
2513 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2514 "and will be tried\n");
2515 }
2516 }
2517
2518 /* Attempt the delivery. */
2519
2520 total_hosts_tried++;
2521 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2522 expanded_hosts != NULL, &message_defer, FALSE);
2523
2524 /* Yield is one of:
2525 OK => connection made, each address contains its result;
2526 message_defer is set for message-specific defers (when all
2527 recipients are marked defer)
2528 DEFER => there was a non-message-specific delivery problem;
2529 ERROR => there was a problem setting up the arguments for a filter,
2530 or there was a problem with expanding added headers
2531 */
2532
2533 /* If the result is not OK, there was a non-message-specific problem.
2534 If the result is DEFER, we need to write to the logs saying what happened
2535 for this particular host, except in the case of authentication and TLS
2536 failures, where the log has already been written. If all hosts defer a
2537 general message is written at the end. */
2538
2539 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2540 first_addr->basic_errno != ERRNO_TLSFAILURE)
2541 write_logs(first_addr, host);
2542
2543 /* If STARTTLS was accepted, but there was a failure in setting up the
2544 TLS session (usually a certificate screwup), and the host is not in
2545 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2546 TLS forcibly turned off. We have to start from scratch with a new SMTP
2547 connection. That's why the retry is done from here, not from within
2548 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2549 session, so the in-clear transmission after those errors, if permitted,
2550 happens inside smtp_deliver().] */
2551
2552 #ifdef SUPPORT_TLS
2553 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2554 ob->tls_tempfail_tryclear &&
2555 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2556 host->address, NULL) != OK)
2557 {
2558 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2559 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2560 first_addr = prepare_addresses(addrlist, host);
2561 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2562 expanded_hosts != NULL, &message_defer, TRUE);
2563 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2564 write_logs(first_addr, host);
2565 }
2566 #endif
2567 }
2568
2569 /* Delivery attempt finished */
2570
2571 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2572 US"ERROR" : US"?";
2573
2574 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2575 message_id, host->name, host->address, addrlist->address,
2576 (addrlist->next == NULL)? "" : " (& others)", rs);
2577
2578 /* Release serialization if set up */
2579
2580 if (serialized) enq_end(serialize_key);
2581
2582 /* If the result is DEFER, or if a host retry record is known to exist, we
2583 need to add an item to the retry chain for updating the retry database
2584 at the end of delivery. We only need to add the item to the top address,
2585 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2586 for any other delivery attempts using the same address. (It is copied into
2587 the unusable tree at the outer level, so even if different address blocks
2588 contain the same address, it still won't get tried again.) */
2589
2590 if (rc == DEFER || retry_host_key != NULL)
2591 {
2592 int delete_flag = (rc != DEFER)? rf_delete : 0;
2593 if (retry_host_key == NULL)
2594 {
2595 retry_host_key = ob->retry_include_ip_address?
2596 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2597 string_sprintf("T:%S%s", host->name, pistring);
2598 }
2599
2600 /* If a delivery of another message over an existing SMTP connection
2601 yields DEFER, we do NOT set up retry data for the host. This covers the
2602 case when there are delays in routing the addresses in the second message
2603 that are so long that the server times out. This is alleviated by not
2604 routing addresses that previously had routing defers when handling an
2605 existing connection, but even so, this case may occur (e.g. if a
2606 previously happily routed address starts giving routing defers). If the
2607 host is genuinely down, another non-continued message delivery will
2608 notice it soon enough. */
2609
2610 if (delete_flag != 0 || !continuing)
2611 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2612
2613 /* We may have tried an expired host, if its retry time has come; ensure
2614 the status reflects the expiry for the benefit of any other addresses. */
2615
2616 if (rc == DEFER)
2617 {
2618 host->status = (host_is_expired)?
2619 hstatus_unusable_expired : hstatus_unusable;
2620 host->why = hwhy_deferred;
2621 }
2622 }
2623
2624 /* If message_defer is set (host was OK, but every recipient got deferred
2625 because of some message-specific problem), or if that had happened
2626 previously so that a message retry key exists, add an appropriate item
2627 to the retry chain. Note that if there was a message defer but now there is
2628 a host defer, the message defer record gets deleted. That seems perfectly
2629 reasonable. Also, stop the message from being remembered as waiting
2630 for this host. */
2631
2632 if (message_defer || retry_message_key != NULL)
2633 {
2634 int delete_flag = message_defer? 0 : rf_delete;
2635 if (retry_message_key == NULL)
2636 {
2637 retry_message_key = ob->retry_include_ip_address?
2638 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2639 message_id) :
2640 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2641 }
2642 retry_add_item(addrlist, retry_message_key,
2643 rf_message | rf_host | delete_flag);
2644 host->update_waiting = FALSE;
2645 }
2646
2647 /* Any return other than DEFER (that is, OK or ERROR) means that the
2648 addresses have got their final statuses filled in for this host. In the OK
2649 case, see if any of them are deferred. */
2650
2651 if (rc == OK)
2652 {
2653 for (addr = addrlist; addr != NULL; addr = addr->next)
2654 {
2655 if (addr->transport_return == DEFER)
2656 {
2657 some_deferred = TRUE;
2658 break;
2659 }
2660 }
2661 }
2662
2663 /* If no addresses deferred or the result was ERROR, return. We do this for
2664 ERROR because a failing filter set-up or add_headers expansion is likely to
2665 fail for any host we try. */
2666
2667 if (rc == ERROR || (rc == OK && !some_deferred))
2668 {
2669 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2670 return TRUE; /* Each address has its status */
2671 }
2672
2673 /* If the result was DEFER or some individual addresses deferred, let
2674 the loop run to try other hosts with the deferred addresses, except for the
2675 case when we were trying to deliver down an existing channel and failed.
2676 Don't try any other hosts in this case. */
2677
2678 if (continuing) break;
2679
2680 /* If the whole delivery, or some individual addresses, were deferred and
2681 there are more hosts that could be tried, do not count this host towards
2682 the hosts_max_try limit if the age of the message is greater than the
2683 maximum retry time for this host. This means we may try try all hosts,
2684 ignoring the limit, when messages have been around for some time. This is
2685 important because if we don't try all hosts, the address will never time
2686 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2687
2688 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2689 {
2690 BOOL timedout;
2691 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2692
2693 if (retry != NULL && retry->rules != NULL)
2694 {
2695 retry_rule *last_rule;
2696 for (last_rule = retry->rules;
2697 last_rule->next != NULL;
2698 last_rule = last_rule->next);
2699 timedout = time(NULL) - received_time > last_rule->timeout;
2700 }
2701 else timedout = TRUE; /* No rule => timed out */
2702
2703 if (timedout)
2704 {
2705 unexpired_hosts_tried--;
2706 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2707 "hosts_max_try (message older than host's retry time)\n");
2708 }
2709 }
2710 } /* End of loop for trying multiple hosts. */
2711
2712 /* This is the end of the loop that repeats iff expired is TRUE and
2713 ob->delay_after_cutoff is FALSE. The second time round we will
2714 try those hosts that haven't been tried since the message arrived. */
2715
2716 DEBUG(D_transport)
2717 {
2718 debug_printf("all IP addresses skipped or deferred at least one address\n");
2719 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
2720 debug_printf("retrying IP addresses not tried since message arrived\n");
2721 }
2722 }
2723
2724
2725 /* Get here if all IP addresses are skipped or defer at least one address. In
2726 MUA wrapper mode, this will happen only for connection or other non-message-
2727 specific failures. Force the delivery status for all addresses to FAIL. */
2728
2729 if (mua_wrapper)
2730 {
2731 for (addr = addrlist; addr != NULL; addr = addr->next)
2732 addr->transport_return = FAIL;
2733 goto END_TRANSPORT;
2734 }
2735
2736 /* In the normal, non-wrapper case, add a standard message to each deferred
2737 address if there hasn't been an error, that is, if it hasn't actually been
2738 tried this time. The variable "expired" will be FALSE if any deliveries were
2739 actually tried, or if there was at least one host that was not expired. That
2740 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
2741 a delivery has been tried, an error code will be set, and the failing of the
2742 message is handled by the retry code later.
2743
2744 If queue_smtp is set, or this transport was called to send a subsequent message
2745 down an existing TCP/IP connection, and something caused the host not to be
2746 found, we end up here, but can detect these cases and handle them specially. */
2747
2748 for (addr = addrlist; addr != NULL; addr = addr->next)
2749 {
2750 /* If host is not NULL, it means that we stopped processing the host list
2751 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
2752 means we need to behave as if some hosts were skipped because their retry
2753 time had not come. Specifically, this prevents the address from timing out.
2754 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
2755 hosts were tried. */
2756
2757 if (host != NULL)
2758 {
2759 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
2760 {
2761 DEBUG(D_transport)
2762 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
2763 "hosts were tried\n");
2764 }
2765 else
2766 {
2767 DEBUG(D_transport)
2768 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
2769 setflag(addr, af_retry_skipped);
2770 }
2771 }
2772
2773 if (queue_smtp) /* no deliveries attempted */
2774 {
2775 addr->transport_return = DEFER;
2776 addr->basic_errno = 0;
2777 addr->message = US"SMTP delivery explicitly queued";
2778 }
2779
2780 else if (addr->transport_return == DEFER &&
2781 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
2782 addr->message == NULL)
2783 {
2784 addr->basic_errno = ERRNO_HRETRY;
2785 if (continue_hostname != NULL)
2786 {
2787 addr->message = US"no host found for existing SMTP connection";
2788 }
2789 else if (expired)
2790 {
2791 addr->message = (ob->delay_after_cutoff)?
2792 US"retry time not reached for any host after a long failure period" :
2793 US"all hosts have been failing for a long time and were last tried "
2794 "after this message arrived";
2795
2796 /* If we are already using fallback hosts, or there are no fallback hosts
2797 defined, convert the result to FAIL to cause a bounce. */
2798
2799 if (addr->host_list == addr->fallback_hosts ||
2800 addr->fallback_hosts == NULL)
2801 addr->transport_return = FAIL;
2802 }
2803 else
2804 {
2805 if (hosts_retry == hosts_total)
2806 addr->message = US"retry time not reached for any host";
2807 else if (hosts_fail == hosts_total)
2808 addr->message = US"all host address lookups failed permanently";
2809 else if (hosts_defer == hosts_total)
2810 addr->message = US"all host address lookups failed temporarily";
2811 else if (hosts_serial == hosts_total)
2812 addr->message = US"connection limit reached for all hosts";
2813 else if (hosts_fail+hosts_defer == hosts_total)
2814 addr->message = US"all host address lookups failed";
2815 else addr->message = US"some host address lookups failed and retry time "
2816 "not reached for other hosts or connection limit reached";
2817 }
2818 }
2819 }
2820
2821 /* Update the database which keeps information about which messages are waiting
2822 for which hosts to become available. Each host in the list has a flag which is
2823 set if the data is to be updated. For some message-specific errors, the flag is
2824 turned off because we don't want follow-on deliveries in those cases. */
2825
2826 transport_update_waiting(hostlist, tblock->name);
2827
2828 END_TRANSPORT:
2829
2830 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2831
2832 return TRUE; /* Each address has its status */
2833 }
2834
2835 /* End of transport/smtp.c */