1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* Copyright (c) The Exim Maintainers 2020 - 2021 */
7 /* See the file NOTICE for conditions of use and distribution. */
12 #if defined(SUPPORT_DANE) && defined(DISABLE_TLS)
13 # error TLS is required for DANE
17 /* Options specific to the smtp transport. This transport also supports LMTP
18 over TCP/IP. The options must be in alphabetic order (note that "_" comes
19 before the lower case letters). Some live in the transport_instance block so as
20 to be publicly visible; these are flagged with opt_public. */
22 #define LOFF(field) OPT_OFF(smtp_transport_options_block, field)
24 optionlist smtp_transport_options[] = {
25 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
26 OPT_OFF(transport_instance, expand_multi_domain) },
27 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
28 LOFF(expand_retry_include_ip_address) },
30 { "address_retry_include_sender", opt_bool,
31 LOFF(address_retry_include_sender) },
32 { "allow_localhost", opt_bool, LOFF(allow_localhost) },
33 #ifdef EXPERIMENTAL_ARC
34 { "arc_sign", opt_stringptr, LOFF(arc_sign) },
36 { "authenticated_sender", opt_stringptr, LOFF(authenticated_sender) },
37 { "authenticated_sender_force", opt_bool, LOFF(authenticated_sender_force) },
38 { "command_timeout", opt_time, LOFF(command_timeout) },
39 { "connect_timeout", opt_time, LOFF(connect_timeout) },
40 { "connection_max_messages", opt_int | opt_public,
41 OPT_OFF(transport_instance, connection_max_messages) },
43 { "dane_require_tls_ciphers", opt_stringptr, LOFF(dane_require_tls_ciphers) },
45 { "data_timeout", opt_time, LOFF(data_timeout) },
46 { "delay_after_cutoff", opt_bool, LOFF(delay_after_cutoff) },
48 { "dkim_canon", opt_stringptr, LOFF(dkim.dkim_canon) },
49 { "dkim_domain", opt_stringptr, LOFF(dkim.dkim_domain) },
50 { "dkim_hash", opt_stringptr, LOFF(dkim.dkim_hash) },
51 { "dkim_identity", opt_stringptr, LOFF(dkim.dkim_identity) },
52 { "dkim_private_key", opt_stringptr, LOFF(dkim.dkim_private_key) },
53 { "dkim_selector", opt_stringptr, LOFF(dkim.dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr, LOFF(dkim.dkim_sign_headers) },
55 { "dkim_strict", opt_stringptr, LOFF(dkim.dkim_strict) },
56 { "dkim_timestamps", opt_stringptr, LOFF(dkim.dkim_timestamps) },
58 { "dns_qualify_single", opt_bool, LOFF(dns_qualify_single) },
59 { "dns_search_parents", opt_bool, LOFF(dns_search_parents) },
60 { "dnssec_request_domains", opt_stringptr, LOFF(dnssec.request) },
61 { "dnssec_require_domains", opt_stringptr, LOFF(dnssec.require) },
62 { "dscp", opt_stringptr, LOFF(dscp) },
63 { "fallback_hosts", opt_stringptr, LOFF(fallback_hosts) },
64 { "final_timeout", opt_time, LOFF(final_timeout) },
65 { "gethostbyname", opt_bool, LOFF(gethostbyname) },
66 { "helo_data", opt_stringptr, LOFF(helo_data) },
67 { "hosts", opt_stringptr, LOFF(hosts) },
68 { "hosts_avoid_esmtp", opt_stringptr, LOFF(hosts_avoid_esmtp) },
69 { "hosts_avoid_pipelining", opt_stringptr, LOFF(hosts_avoid_pipelining) },
71 { "hosts_avoid_tls", opt_stringptr, LOFF(hosts_avoid_tls) },
73 { "hosts_max_try", opt_int, LOFF(hosts_max_try) },
74 { "hosts_max_try_hardlimit", opt_int, LOFF(hosts_max_try_hardlimit) },
76 { "hosts_nopass_tls", opt_stringptr, LOFF(hosts_nopass_tls) },
77 { "hosts_noproxy_tls", opt_stringptr, LOFF(hosts_noproxy_tls) },
79 { "hosts_override", opt_bool, LOFF(hosts_override) },
80 #ifndef DISABLE_PIPE_CONNECT
81 { "hosts_pipe_connect", opt_stringptr, LOFF(hosts_pipe_connect) },
83 { "hosts_randomize", opt_bool, LOFF(hosts_randomize) },
84 #if !defined(DISABLE_TLS) && !defined(DISABLE_OCSP)
85 { "hosts_request_ocsp", opt_stringptr, LOFF(hosts_request_ocsp) },
87 { "hosts_require_alpn", opt_stringptr, LOFF(hosts_require_alpn) },
88 { "hosts_require_auth", opt_stringptr, LOFF(hosts_require_auth) },
91 { "hosts_require_dane", opt_stringptr, LOFF(hosts_require_dane) },
94 { "hosts_require_ocsp", opt_stringptr, LOFF(hosts_require_ocsp) },
96 { "hosts_require_tls", opt_stringptr, LOFF(hosts_require_tls) },
98 { "hosts_try_auth", opt_stringptr, LOFF(hosts_try_auth) },
99 { "hosts_try_chunking", opt_stringptr, LOFF(hosts_try_chunking) },
101 { "hosts_try_dane", opt_stringptr, LOFF(hosts_try_dane) },
103 { "hosts_try_fastopen", opt_stringptr, LOFF(hosts_try_fastopen) },
105 { "hosts_try_prdr", opt_stringptr, LOFF(hosts_try_prdr) },
108 { "hosts_verify_avoid_tls", opt_stringptr, LOFF(hosts_verify_avoid_tls) },
110 { "interface", opt_stringptr, LOFF(interface) },
111 { "keepalive", opt_bool, LOFF(keepalive) },
112 { "lmtp_ignore_quota", opt_bool, LOFF(lmtp_ignore_quota) },
113 { "max_rcpt", opt_int | opt_public,
114 OPT_OFF(transport_instance, max_addresses) },
115 { "message_linelength_limit", opt_int, LOFF(message_linelength_limit) },
116 { "multi_domain", opt_expand_bool | opt_public,
117 OPT_OFF(transport_instance, multi_domain) },
118 { "port", opt_stringptr, LOFF(port) },
119 { "protocol", opt_stringptr, LOFF(protocol) },
120 { "retry_include_ip_address", opt_expand_bool, LOFF(retry_include_ip_address) },
121 { "serialize_hosts", opt_stringptr, LOFF(serialize_hosts) },
122 { "size_addition", opt_int, LOFF(size_addition) },
124 { "socks_proxy", opt_stringptr, LOFF(socks_proxy) },
127 { "tls_alpn", opt_stringptr, LOFF(tls_alpn) },
128 { "tls_certificate", opt_stringptr, LOFF(tls_certificate) },
129 { "tls_crl", opt_stringptr, LOFF(tls_crl) },
130 { "tls_dh_min_bits", opt_int, LOFF(tls_dh_min_bits) },
131 { "tls_privatekey", opt_stringptr, LOFF(tls_privatekey) },
132 { "tls_require_ciphers", opt_stringptr, LOFF(tls_require_ciphers) },
133 # ifndef DISABLE_TLS_RESUME
134 { "tls_resumption_hosts", opt_stringptr, LOFF(tls_resumption_hosts) },
136 { "tls_sni", opt_stringptr, LOFF(tls_sni) },
137 { "tls_tempfail_tryclear", opt_bool, LOFF(tls_tempfail_tryclear) },
138 { "tls_try_verify_hosts", opt_stringptr, LOFF(tls_try_verify_hosts) },
139 { "tls_verify_cert_hostnames", opt_stringptr, LOFF(tls_verify_cert_hostnames)},
140 { "tls_verify_certificates", opt_stringptr, LOFF(tls_verify_certificates) },
141 { "tls_verify_hosts", opt_stringptr, LOFF(tls_verify_hosts) },
144 { "utf8_downconvert", opt_stringptr, LOFF(utf8_downconvert) },
148 /* Size of the options list. An extern variable has to be used so that its
149 address can appear in the tables drtables.c. */
151 int smtp_transport_options_count = nelem(smtp_transport_options);
157 smtp_transport_options_block smtp_transport_option_defaults = {0};
158 void smtp_transport_init(transport_instance *tblock) {}
159 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
160 void smtp_transport_closedown(transport_instance *tblock) {}
162 #else /*!MACRO_PREDEF*/
165 /* Default private options block for the smtp transport. */
167 smtp_transport_options_block smtp_transport_option_defaults = {
168 /* All non-mentioned elements 0/NULL/FALSE */
169 .helo_data = US"$primary_hostname",
170 .protocol = US"smtp",
171 .hosts_try_chunking = US"*",
173 .hosts_try_dane = US"*",
175 .hosts_try_fastopen = US"*",
177 .hosts_try_prdr = US"*",
180 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
182 .command_timeout = 5*60,
183 .connect_timeout = 5*60,
184 .data_timeout = 5*60,
185 .final_timeout = 10*60,
186 .size_addition = 1024,
188 .hosts_max_try_hardlimit = 50,
189 .message_linelength_limit = 998,
190 .address_retry_include_sender = TRUE,
191 .dns_qualify_single = TRUE,
192 .dnssec = { .request= US"*", .require=NULL },
193 .delay_after_cutoff = TRUE,
195 .retry_include_ip_address = TRUE,
197 .tls_verify_certificates = US"system",
198 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
199 .tls_tempfail_tryclear = TRUE,
200 .tls_try_verify_hosts = US"*",
201 .tls_verify_cert_hostnames = US"*",
204 .utf8_downconvert = US"-1",
208 { .dkim_hash = US"sha256", },
212 /* some DSN flags for use later */
214 static int rf_list[] = {rf_notify_never, rf_notify_success,
215 rf_notify_failure, rf_notify_delay };
217 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
223 static uschar *smtp_command; /* Points to last cmd for error messages */
224 static uschar *mail_command; /* Points to MAIL cmd for error messages */
225 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
226 static BOOL update_waiting; /* TRUE to update the "wait" database */
228 /*XXX move to smtp_context */
229 static BOOL pipelining_active; /* current transaction is in pipe mode */
232 static unsigned ehlo_response(uschar * buf, unsigned checks);
235 /******************************************************************************/
238 smtp_deliver_init(void)
242 const pcre2_code ** re;
243 const uschar * string;
246 { ®ex_AUTH, AUTHS_REGEX },
247 { ®ex_CHUNKING, US"\\n250[\\s\\-]CHUNKING(\\s|\\n|$)" },
248 { ®ex_DSN, US"\\n250[\\s\\-]DSN(\\s|\\n|$)" },
249 { ®ex_IGNOREQUOTA, US"\\n250[\\s\\-]IGNOREQUOTA(\\s|\\n|$)" },
250 { ®ex_PIPELINING, US"\\n250[\\s\\-]PIPELINING(\\s|\\n|$)" },
251 { ®ex_SIZE, US"\\n250[\\s\\-]SIZE(\\s|\\n|$)" },
254 { ®ex_STARTTLS, US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)" },
257 { ®ex_PRDR, US"\\n250[\\s\\-]PRDR(\\s|\\n|$)" },
260 { ®ex_UTF8, US"\\n250[\\s\\-]SMTPUTF8(\\s|\\n|$)" },
262 #ifndef DISABLE_PIPE_CONNECT
263 { ®ex_EARLY_PIPE, US"\\n250[\\s\\-]" EARLY_PIPE_FEATURE_NAME "(\\s|\\n|$)" },
265 #ifdef EXPERIMENTAL_ESMTP_LIMITS
266 { ®ex_LIMITS, US"\\n250[\\s\\-]LIMITS\\s" },
270 for (struct list * l = list; l < list + nelem(list); l++)
272 *l->re = regex_must_compile(l->string, FALSE, TRUE);
276 /*************************************************
277 * Setup entry point *
278 *************************************************/
280 /* This function is called when the transport is about to be used,
281 but before running it in a sub-process. It is used for two things:
283 (1) To set the fallback host list in addresses, when delivering.
284 (2) To pass back the interface, port, protocol, and other options, for use
285 during callout verification.
288 tblock pointer to the transport instance block
289 addrlist list of addresses about to be transported
290 tf if not NULL, pointer to block in which to return options
291 uid the uid that will be set (not used)
292 gid the gid that will be set (not used)
293 errmsg place for error message (not used)
295 Returns: OK always (FAIL, DEFER not used)
299 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
300 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
302 smtp_transport_options_block *ob = SOB tblock->options_block;
304 /* Pass back options if required. This interface is getting very messy. */
308 tf->interface = ob->interface;
310 tf->protocol = ob->protocol;
311 tf->hosts = ob->hosts;
312 tf->hosts_override = ob->hosts_override;
313 tf->hosts_randomize = ob->hosts_randomize;
314 tf->gethostbyname = ob->gethostbyname;
315 tf->qualify_single = ob->dns_qualify_single;
316 tf->search_parents = ob->dns_search_parents;
317 tf->helo_data = ob->helo_data;
320 /* Set the fallback host list for all the addresses that don't have fallback
321 host lists, provided that the local host wasn't present in the original host
324 if (!testflag(addrlist, af_local_host_removed))
325 for (; addrlist; addrlist = addrlist->next)
326 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
333 /*************************************************
334 * Initialization entry point *
335 *************************************************/
337 /* Called for each instance, after its options have been read, to
338 enable consistency checks to be done, or anything else that needs
341 Argument: pointer to the transport instance block
346 smtp_transport_init(transport_instance *tblock)
348 smtp_transport_options_block *ob = SOB tblock->options_block;
349 int old_pool = store_pool;
351 /* Retry_use_local_part defaults FALSE if unset */
353 if (tblock->retry_use_local_part == TRUE_UNSET)
354 tblock->retry_use_local_part = FALSE;
356 /* Set the default port according to the protocol */
359 ob->port = strcmpic(ob->protocol, US"lmtp") == 0
361 : strcmpic(ob->protocol, US"smtps") == 0
362 ? US"smtps" : US"smtp";
364 /* Set up the setup entry point, to be called before subprocesses for this
367 tblock->setup = smtp_transport_setup;
369 /* Complain if any of the timeouts are zero. */
371 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
372 ob->final_timeout <= 0)
373 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
374 "command, data, or final timeout value is zero for %s transport",
377 /* If hosts_override is set and there are local hosts, set the global
378 flag that stops verify from showing router hosts. */
380 if (ob->hosts_override && ob->hosts) tblock->overrides_hosts = TRUE;
382 /* If there are any fallback hosts listed, build a chain of host items
383 for them, but do not do any lookups at this time. */
385 store_pool = POOL_PERM;
386 host_build_hostlist(&ob->fallback_hostlist, ob->fallback_hosts, FALSE);
387 store_pool = old_pool;
394 /*************************************************
395 * Set delivery info into all active addresses *
396 *************************************************/
398 /* Only addresses whose status is >= PENDING are relevant. A lesser
399 status means that an address is not currently being processed.
402 addrlist points to a chain of addresses
403 errno_value to put in each address's errno field
404 msg to put in each address's message field
405 rc to put in each address's transport_return field
406 pass_message if TRUE, set the "pass message" flag in the address
407 host if set, mark addrs as having used this host
408 smtp_greeting from peer
409 helo_response from peer
410 start points to timestamp of delivery start
412 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
413 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
414 this particular type of timeout.
420 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
421 BOOL pass_message, host_item * host,
422 #ifdef EXPERIMENTAL_DSN_INFO
423 const uschar * smtp_greeting, const uschar * helo_response,
425 struct timeval * start
429 struct timeval deliver_time;
431 if (errno_value == ERRNO_CONNECTTIMEOUT)
433 errno_value = ETIMEDOUT;
434 orvalue = RTEF_CTOUT;
436 timesince(&deliver_time, start);
438 for (address_item * addr = addrlist; addr; addr = addr->next)
439 if (addr->transport_return >= PENDING)
441 addr->basic_errno = errno_value;
442 addr->more_errno |= orvalue;
443 addr->delivery_time = deliver_time;
447 if (pass_message) setflag(addr, af_pass_message);
449 addr->transport_return = rc;
452 addr->host_used = host;
453 #ifdef EXPERIMENTAL_DSN_INFO
455 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
456 addr->smtp_greeting = smtp_greeting;
459 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
460 addr->helo_response = helo_response;
467 set_errno_nohost(address_item * addrlist, int errno_value, uschar * msg, int rc,
468 BOOL pass_message, struct timeval * start)
470 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL,
471 #ifdef EXPERIMENTAL_DSN_INFO
478 /*************************************************
479 * Check an SMTP response *
480 *************************************************/
482 /* This function is given an errno code and the SMTP response buffer
483 to analyse, together with the host identification for generating messages. It
484 sets an appropriate message and puts the first digit of the response code into
485 the yield variable. If no response was actually read, a suitable digit is
489 host the current host, to get its name for messages
490 errno_value pointer to the errno value
491 more_errno from the top address for use with ERRNO_FILTER_FAIL
492 buffer the SMTP response buffer
493 yield where to put a one-digit SMTP response code
494 message where to put an error message
495 pass_message set TRUE if message is an SMTP response
497 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
501 check_response(host_item *host, int *errno_value, int more_errno,
502 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
504 uschar * pl = pipelining_active ? US"pipelined " : US"";
507 *yield = '4'; /* Default setting is to give a temporary error */
511 case ETIMEDOUT: /* Handle response timeout */
512 *message = US string_sprintf("SMTP timeout after %s%s",
514 if (transport_count > 0)
515 *message = US string_sprintf("%s (%d bytes written)", *message,
519 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
520 s = string_printing(buffer);
521 while (isspace(*s)) s++;
523 ? string_sprintf("Malformed SMTP reply (an empty line) "
524 "in response to %s%s", pl, smtp_command)
525 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
526 pl, smtp_command, s);
529 case ERRNO_TLSFAILURE: /* Handle bad first read; can happen with
531 *message = US"bad first read from TLS conn";
534 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
535 can't send QUIT as we mustn't end the DATA. */
536 *message = string_sprintf("transport filter process failed (%d)%s",
538 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
541 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
542 can't send QUIT as we mustn't end the DATA. */
544 string_sprintf("failed to expand headers_add or headers_remove: %s",
545 expand_string_message);
548 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
549 *message = US"failed to write a data block";
553 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
554 *message = US"utf8 support required but not offered for forwarding";
555 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
560 /* Handle error responses from the remote mailer. */
564 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
565 "%s", pl, smtp_command, s = string_printing(buffer));
566 *pass_message = TRUE;
571 /* No data was read. If there is no errno, this must be the EOF (i.e.
572 connection closed) case, which causes deferral. An explicit connection reset
573 error has the same effect. Otherwise, put the host's identity in the message,
574 leaving the errno value to be interpreted as well. In all cases, we have to
575 assume the connection is now dead. */
577 if (*errno_value == 0 || *errno_value == ECONNRESET)
579 *errno_value = ERRNO_SMTPCLOSED;
580 *message = US string_sprintf("Remote host closed connection "
581 "in response to %s%s", pl, smtp_command);
584 *message = US string_sprintf("%s [%s]", host->name, host->address);
591 /*************************************************
592 * Write error message to logs *
593 *************************************************/
595 /* This writes to the main log and to the message log.
598 host the current host
599 detail the current message (addr_item->message)
600 basic_errno the errno (addr_item->basic_errno)
606 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
608 gstring * message = LOGGING(outgoing_port)
609 ? string_fmt_append(NULL, "H=%s [%s]:%d", host->name, host->address,
610 host->port == PORT_NONE ? 25 : host->port)
611 : string_fmt_append(NULL, "H=%s [%s]", host->name, host->address);
615 message = string_fmt_append(message, ": %s", suffix);
617 message = string_fmt_append(message, ": %s", strerror(basic_errno));
620 message = string_fmt_append(message, " %s", exim_errstr(basic_errno));
622 log_write(0, LOG_MAIN, "%s", string_from_gstring(message));
623 deliver_msglog("%s %s\n", tod_stamp(tod_log), message->s);
627 msglog_line(host_item * host, uschar * message)
629 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
630 host->name, host->address, message);
635 #ifndef DISABLE_EVENT
636 /*************************************************
637 * Post-defer action *
638 *************************************************/
640 /* This expands an arbitrary per-transport string.
641 It might, for example, be used to write to the database log.
644 addr the address item containing error information
645 host the current host
652 deferred_event_raise(address_item * addr, host_item * host, uschar * evstr)
654 uschar * action = addr->transport->event_action;
655 const uschar * save_domain;
661 save_domain = deliver_domain;
662 save_local = deliver_localpart;
664 /*XXX would ip & port already be set up? */
665 deliver_host_address = string_copy(host->address);
666 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
667 event_defer_errno = addr->basic_errno;
669 router_name = addr->router->name;
670 transport_name = addr->transport->name;
671 deliver_domain = addr->domain;
672 deliver_localpart = addr->local_part;
674 (void) event_raise(action, evstr,
676 ? addr->basic_errno > 0
677 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
678 : string_copy(addr->message)
679 : addr->basic_errno > 0
680 ? string_copy(US strerror(addr->basic_errno))
684 deliver_localpart = save_local;
685 deliver_domain = save_domain;
686 router_name = transport_name = NULL;
690 /*************************************************
691 * Reap SMTP specific responses *
692 *************************************************/
694 smtp_discard_responses(smtp_context * sx, smtp_transport_options_block * ob,
697 uschar flushbuffer[4096];
701 if (!smtp_read_response(sx, flushbuffer, sizeof(flushbuffer),
702 '2', ob->command_timeout)
703 && (errno != 0 || flushbuffer[0] == 0))
710 /* Return boolean success */
713 smtp_reap_banner(smtp_context * sx)
716 #if defined(__linux__) && defined(TCP_QUICKACK)
717 { /* Hack to get QUICKACK disabled; has to be right after 3whs, and has to on->off */
718 int sock = sx->cctx.sock;
719 struct pollfd p = {.fd = sock, .events = POLLOUT};
720 if (poll(&p, 1, 1000) >= 0) /* retval test solely for compiler quitening */
722 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &on, sizeof(on));
723 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
727 good_response = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
728 '2', (SOB sx->conn_args.ob)->command_timeout);
729 #ifdef EXPERIMENTAL_DSN_INFO
730 sx->smtp_greeting = string_copy(sx->buffer);
732 return good_response;
736 smtp_reap_ehlo(smtp_context * sx)
738 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
739 (SOB sx->conn_args.ob)->command_timeout))
741 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
743 #ifdef EXPERIMENTAL_DSN_INFO
744 sx->helo_response = string_copy(sx->buffer);
750 #ifdef EXPERIMENTAL_DSN_INFO
751 sx->helo_response = string_copy(sx->buffer);
753 #ifndef DISABLE_EVENT
754 (void) event_raise(sx->conn_args.tblock->event_action,
755 US"smtp:ehlo", sx->buffer, NULL);
761 /******************************************************************************/
763 #ifdef EXPERIMENTAL_ESMTP_LIMITS
764 /* If TLS, or TLS not offered, called with the EHLO response in the buffer.
765 Check it for a LIMITS keyword and parse values into the smtp context structure.
767 We don't bother with peers that we won't talk TLS to, even though they can,
768 just ignore their LIMITS advice (if any) and treat them as if they do not.
769 This saves us dealing with a duplicate set of values. */
772 ehlo_response_limits_read(smtp_context * sx)
776 /* matches up to just after the first space after the keyword */
778 if (regex_match(regex_LIMITS, sx->buffer, -1, &match))
779 for (const uschar * s = sx->buffer + Ustrlen(match); *s; )
781 while (isspace(*s)) s++;
782 if (*s == '\n') break;
784 if (strncmpic(s, US"MAILMAX=", 8) == 0)
786 sx->peer_limit_mail = atoi(CS (s += 8));
787 while (isdigit(*s)) s++;
789 else if (strncmpic(s, US"RCPTMAX=", 8) == 0)
791 sx->peer_limit_rcpt = atoi(CS (s += 8));
792 while (isdigit(*s)) s++;
794 else if (strncmpic(s, US"RCPTDOMAINMAX=", 14) == 0)
796 sx->peer_limit_rcptdom = atoi(CS (s += 14));
797 while (isdigit(*s)) s++;
800 while (*s && !isspace(*s)) s++;
804 /* Apply given values to the current connection */
806 ehlo_limits_apply(smtp_context * sx,
807 unsigned limit_mail, unsigned limit_rcpt, unsigned limit_rcptdom)
809 if (limit_mail && limit_mail < sx->max_mail) sx->max_mail = limit_mail;
810 if (limit_rcpt && limit_rcpt < sx->max_rcpt) sx->max_rcpt = limit_rcpt;
813 DEBUG(D_transport) debug_printf("will treat as !multi_domain\n");
814 sx->single_rcpt_domain = TRUE;
818 /* Apply values from EHLO-resp to the current connection */
820 ehlo_response_limits_apply(smtp_context * sx)
822 ehlo_limits_apply(sx, sx->peer_limit_mail, sx->peer_limit_rcpt,
823 sx->peer_limit_rcptdom);
826 /* Apply values read from cache to the current connection */
828 ehlo_cache_limits_apply(smtp_context * sx)
830 ehlo_limits_apply(sx, sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
831 sx->ehlo_resp.limit_rcptdom);
835 /******************************************************************************/
837 #ifndef DISABLE_PIPE_CONNECT
839 ehlo_cache_key(const smtp_context * sx)
841 host_item * host = sx->conn_args.host;
842 return Ustrchr(host->address, ':')
843 ? string_sprintf("[%s]:%d.EHLO", host->address,
844 host->port == PORT_NONE ? sx->port : host->port)
845 : string_sprintf("%s:%d.EHLO", host->address,
846 host->port == PORT_NONE ? sx->port : host->port);
849 /* Cache EHLO-response info for use by early-pipe.
851 - During a normal flow on EHLO response (either cleartext or under TLS),
852 when we are willing to do PIPECONNECT and it is offered
853 - During an early-pipe flow on receiving the actual EHLO response and noting
854 disparity versus the cached info used, when PIPECONNECT is still being offered
856 We assume that suitable values have been set in the sx.ehlo_resp structure for
857 features and auths; we handle the copy of limits. */
860 write_ehlo_cache_entry(smtp_context * sx)
862 open_db dbblock, * dbm_file;
864 #ifdef EXPERIMENTAL_ESMTP_LIMITS
865 sx->ehlo_resp.limit_mail = sx->peer_limit_mail;
866 sx->ehlo_resp.limit_rcpt = sx->peer_limit_rcpt;
867 sx->ehlo_resp.limit_rcptdom = sx->peer_limit_rcptdom;
870 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
872 uschar * ehlo_resp_key = ehlo_cache_key(sx);
873 dbdata_ehlo_resp er = { .data = sx->ehlo_resp };
876 #ifdef EXPERIMENTAL_ESMTP_LIMITS
877 if (sx->ehlo_resp.limit_mail || sx->ehlo_resp.limit_rcpt || sx->ehlo_resp.limit_rcptdom)
878 debug_printf("writing clr %04x/%04x cry %04x/%04x lim %05d/%05d/%05d\n",
879 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
880 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths,
881 sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
882 sx->ehlo_resp.limit_rcptdom);
885 debug_printf("writing clr %04x/%04x cry %04x/%04x\n",
886 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
887 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths);
889 dbfn_write(dbm_file, ehlo_resp_key, &er, (int)sizeof(er));
890 dbfn_close(dbm_file);
895 invalidate_ehlo_cache_entry(smtp_context * sx)
897 open_db dbblock, * dbm_file;
899 if ( sx->early_pipe_active
900 && (dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
902 uschar * ehlo_resp_key = ehlo_cache_key(sx);
903 dbfn_delete(dbm_file, ehlo_resp_key);
904 dbfn_close(dbm_file);
909 read_ehlo_cache_entry(smtp_context * sx)
914 if (!(dbm_file = dbfn_open(US"misc", O_RDONLY, &dbblock, FALSE, TRUE)))
915 { DEBUG(D_transport) debug_printf("ehlo-cache: no misc DB\n"); }
918 uschar * ehlo_resp_key = ehlo_cache_key(sx);
919 dbdata_ehlo_resp * er;
921 if (!(er = dbfn_read_enforce_length(dbm_file, ehlo_resp_key, sizeof(dbdata_ehlo_resp))))
922 { DEBUG(D_transport) debug_printf("no ehlo-resp record\n"); }
923 else if (time(NULL) - er->time_stamp > retry_data_expire)
925 DEBUG(D_transport) debug_printf("ehlo-resp record too old\n");
926 dbfn_close(dbm_file);
927 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
928 dbfn_delete(dbm_file, ehlo_resp_key);
933 #ifdef EXPERIMENTAL_ESMTP_LIMITS
934 if (er->data.limit_mail || er->data.limit_rcpt || er->data.limit_rcptdom)
935 debug_printf("EHLO response bits from cache:"
936 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x lim %05d/%05d/%05d\n",
937 er->data.cleartext_features, er->data.cleartext_auths,
938 er->data.crypted_features, er->data.crypted_auths,
939 er->data.limit_mail, er->data.limit_rcpt, er->data.limit_rcptdom);
942 debug_printf("EHLO response bits from cache:"
943 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x\n",
944 er->data.cleartext_features, er->data.cleartext_auths,
945 er->data.crypted_features, er->data.crypted_auths);
947 sx->ehlo_resp = er->data;
948 #ifdef EXPERIMENTAL_ESMTP_LIMITS
949 ehlo_cache_limits_apply(sx);
951 dbfn_close(dbm_file);
954 dbfn_close(dbm_file);
961 /* Return an auths bitmap for the set of AUTH methods offered by the server
962 which match our authenticators. */
964 static unsigned short
965 study_ehlo_auths(smtp_context * sx)
970 unsigned short authbits = 0;
972 if (!sx->esmtp) return 0;
973 if (!regex_AUTH) regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
974 if (!regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)) return 0;
975 expand_nmax = -1; /* reset */
976 names = string_copyn(expand_nstring[1], expand_nlength[1]);
978 for (au = auths, authnum = 0; au; au = au->next, authnum++) if (au->client)
980 const uschar * list = names;
982 for (int sep = ' '; s = string_nextinlist(&list, &sep, NULL, 0); )
983 if (strcmpic(au->public_name, s) == 0)
984 { authbits |= BIT(authnum); break; }
988 debug_printf("server offers %s AUTH, methods '%s', bitmap 0x%04x\n",
989 tls_out.active.sock >= 0 ? "crypted" : "plaintext", names, authbits);
991 if (tls_out.active.sock >= 0)
992 sx->ehlo_resp.crypted_auths = authbits;
994 sx->ehlo_resp.cleartext_auths = authbits;
1001 /* Wait for and check responses for early-pipelining.
1003 Called from the lower-level smtp_read_response() function
1004 used for general code that assume synchronisation, if context
1005 flags indicate outstanding early-pipelining commands. Also
1006 called fom sync_responses() which handles pipelined commands.
1009 sx smtp connection context
1010 countp number of outstanding responses, adjusted on return
1014 DEFER error on first read of TLS'd conn
1015 FAIL SMTP error in response
1018 smtp_reap_early_pipe(smtp_context * sx, int * countp)
1020 BOOL pending_BANNER = sx->pending_BANNER;
1021 BOOL pending_EHLO = sx->pending_EHLO;
1024 sx->pending_BANNER = FALSE; /* clear early to avoid recursion */
1025 sx->pending_EHLO = FALSE;
1029 DEBUG(D_transport) debug_printf("%s expect banner\n", __FUNCTION__);
1031 if (!smtp_reap_banner(sx))
1033 DEBUG(D_transport) debug_printf("bad banner\n");
1034 if (tls_out.active.sock >= 0) rc = DEFER;
1041 unsigned peer_offered;
1042 unsigned short authbits = 0, * ap;
1044 DEBUG(D_transport) debug_printf("%s expect ehlo\n", __FUNCTION__);
1046 if (!smtp_reap_ehlo(sx))
1048 DEBUG(D_transport) debug_printf("bad response for EHLO\n");
1049 if (tls_out.active.sock >= 0) rc = DEFER;
1053 /* Compare the actual EHLO response extensions and AUTH methods to the cached
1054 value we assumed; on difference, dump or rewrite the cache and arrange for a
1057 ap = tls_out.active.sock < 0
1058 ? &sx->ehlo_resp.cleartext_auths : &sx->ehlo_resp.crypted_auths;
1060 peer_offered = ehlo_response(sx->buffer,
1061 (tls_out.active.sock < 0 ? OPTION_TLS : 0)
1062 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
1063 | OPTION_UTF8 | OPTION_EARLY_PIPE
1065 #ifdef EXPERIMENTAL_ESMTP_LIMITS
1066 if (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1067 ehlo_response_limits_read(sx);
1069 if ( peer_offered != sx->peer_offered
1070 || (authbits = study_ehlo_auths(sx)) != *ap)
1073 debug_printf("EHLO %s extensions changed, 0x%04x/0x%04x -> 0x%04x/0x%04x\n",
1074 tls_out.active.sock < 0 ? "cleartext" : "crypted",
1075 sx->peer_offered, *ap, peer_offered, authbits);
1076 if (peer_offered & OPTION_EARLY_PIPE)
1078 *(tls_out.active.sock < 0
1079 ? &sx->ehlo_resp.cleartext_features : &sx->ehlo_resp.crypted_features) =
1082 write_ehlo_cache_entry(sx);
1085 invalidate_ehlo_cache_entry(sx);
1087 return OK; /* just carry on */
1089 #ifdef EXPERIMENTAL_ESMTP_LIMITS
1090 /* If we are handling LIMITS, compare the actual EHLO LIMITS values with the
1091 cached values and invalidate cache if different. OK to carry on with
1092 connect since values are advisory. */
1094 if ( (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1095 && ( sx->peer_limit_mail != sx->ehlo_resp.limit_mail
1096 || sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt
1097 || sx->peer_limit_rcptdom != sx->ehlo_resp.limit_rcptdom
1102 debug_printf("EHLO LIMITS changed:");
1103 if (sx->peer_limit_mail != sx->ehlo_resp.limit_mail)
1104 debug_printf(" MAILMAX %u -> %u\n", sx->ehlo_resp.limit_mail, sx->peer_limit_mail);
1105 else if (sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt)
1106 debug_printf(" RCPTMAX %u -> %u\n", sx->ehlo_resp.limit_rcpt, sx->peer_limit_rcpt);
1108 debug_printf(" RCPTDOMAINMAX %u -> %u\n", sx->ehlo_resp.limit_rcptdom, sx->peer_limit_rcptdom);
1110 invalidate_ehlo_cache_entry(sx);
1118 invalidate_ehlo_cache_entry(sx);
1119 (void) smtp_discard_responses(sx, sx->conn_args.ob, *countp);
1122 #endif /*!DISABLE_PIPE_CONNECT*/
1125 /*************************************************
1126 * Synchronize SMTP responses *
1127 *************************************************/
1129 /* This function is called from smtp_deliver() to receive SMTP responses from
1130 the server, and match them up with the commands to which they relate. When
1131 PIPELINING is not in use, this function is called after every command, and is
1132 therefore somewhat over-engineered, but it is simpler to use a single scheme
1133 that works both with and without PIPELINING instead of having two separate sets
1136 The set of commands that are buffered up with pipelining may start with MAIL
1137 and may end with DATA; in between are RCPT commands that correspond to the
1138 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
1139 etc.) are never buffered.
1141 Errors after MAIL or DATA abort the whole process leaving the response in the
1142 buffer. After MAIL, pending responses are flushed, and the original command is
1143 re-instated in big_buffer for error messages. For RCPT commands, the remote is
1144 permitted to reject some recipient addresses while accepting others. However
1145 certain errors clearly abort the whole process. Set the value in
1146 transport_return to PENDING_OK if the address is accepted. If there is a
1147 subsequent general error, it will get reset accordingly. If not, it will get
1148 converted to OK at the end.
1151 sx smtp connection context
1152 count the number of responses to read
1153 pending_DATA 0 if last command sent was not DATA
1154 +1 if previously had a good recipient
1155 -1 if not previously had a good recipient
1157 Returns: 3 if at least one address had 2xx and one had 5xx
1158 2 if at least one address had 5xx but none had 2xx
1159 1 if at least one host had a 2xx response, but none had 5xx
1160 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
1161 -1 timeout while reading RCPT response
1162 -2 I/O or other non-response error for RCPT
1163 -3 DATA or MAIL failed - errno and buffer set
1164 -4 banner or EHLO failed (early-pipelining)
1165 -5 banner or EHLO failed (early-pipelining, TLS)
1169 sync_responses(smtp_context * sx, int count, int pending_DATA)
1171 address_item * addr = sx->sync_addr;
1172 smtp_transport_options_block * ob = sx->conn_args.ob;
1175 #ifndef DISABLE_PIPE_CONNECT
1177 if ((rc = smtp_reap_early_pipe(sx, &count)) != OK)
1178 return rc == FAIL ? -4 : -5;
1181 /* Handle the response for a MAIL command. On error, reinstate the original
1182 command in big_buffer for error message use, and flush any further pending
1183 responses before returning, except after I/O errors and timeouts. */
1185 if (sx->pending_MAIL)
1187 DEBUG(D_transport) debug_printf("%s expect mail\n", __FUNCTION__);
1189 sx->pending_MAIL = sx->RCPT_452 = FALSE;
1190 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1191 '2', ob->command_timeout))
1193 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
1194 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
1195 if (errno == ERRNO_TLSFAILURE)
1197 if (errno == 0 && sx->buffer[0] != 0)
1200 if (sx->buffer[0] == '4')
1202 save_errno = ERRNO_MAIL4XX;
1203 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1205 count = smtp_discard_responses(sx, ob, count);
1209 if (pending_DATA) count--; /* Number of RCPT responses to come */
1210 while (count-- > 0) /* Mark any pending addrs with the host used */
1212 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
1213 addr->host_used = sx->conn_args.host;
1220 if (pending_DATA) count--; /* Number of RCPT responses to come */
1222 /* Read and handle the required number of RCPT responses, matching each one up
1223 with an address by scanning for the next address whose status is PENDING_DEFER.
1228 while (addr->transport_return != PENDING_DEFER)
1229 if (!(addr = addr->next))
1232 /* The address was accepted */
1233 addr->host_used = sx->conn_args.host;
1235 DEBUG(D_transport) debug_printf("%s expect rcpt for %s\n", __FUNCTION__, addr->address);
1236 if (smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1237 '2', ob->command_timeout))
1240 addr->transport_return = PENDING_OK;
1242 /* If af_dr_retry_exists is set, there was a routing delay on this address;
1243 ensure that any address-specific retry record is expunged. We do this both
1244 for the basic key and for the version that also includes the sender. */
1246 if (testflag(addr, af_dr_retry_exists))
1248 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
1250 retry_add_item(addr, altkey, rf_delete);
1251 retry_add_item(addr, addr->address_retry_key, rf_delete);
1255 /* Error on first TLS read */
1257 else if (errno == ERRNO_TLSFAILURE)
1260 /* Timeout while reading the response */
1262 else if (errno == ETIMEDOUT)
1264 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
1265 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1266 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE, &sx->delivery_start);
1267 retry_add_item(addr, addr->address_retry_key, 0);
1268 update_waiting = FALSE;
1272 /* Handle other errors in obtaining an SMTP response by returning -1. This
1273 will cause all the addresses to be deferred. Restore the SMTP command in
1274 big_buffer for which we are checking the response, so the error message
1277 else if (errno != 0 || sx->buffer[0] == 0)
1279 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer }, * g = &gs;
1281 /* Use taint-unchecked routines for writing into big_buffer, trusting
1282 that we'll never expand it. */
1284 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, "RCPT TO:<%s>",
1285 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1286 string_from_gstring(g);
1290 /* Handle SMTP permanent and temporary response codes. */
1295 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
1296 "%s", transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes),
1297 string_printing(sx->buffer));
1298 setflag(addr, af_pass_message);
1300 msglog_line(sx->conn_args.host, addr->message);
1302 /* The response was 5xx */
1304 if (sx->buffer[0] == '5')
1306 addr->transport_return = FAIL;
1310 /* The response was 4xx */
1314 addr->transport_return = DEFER;
1315 addr->basic_errno = ERRNO_RCPT4XX;
1316 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1320 #ifndef DISABLE_EVENT
1321 event_defer_errno = addr->more_errno;
1322 msg_event_raise(US"msg:rcpt:host:defer", addr);
1324 /* If a 452 and we've had at least one 2xx or 5xx, set next_addr to the
1325 start point for another MAIL command. */
1327 if (addr->more_errno >> 8 == 52 && yield & 3)
1329 if (!sx->RCPT_452) /* initialised at MAIL-ack above */
1332 debug_printf("%s: seen first 452 too-many-rcpts\n", __FUNCTION__);
1333 sx->RCPT_452 = TRUE;
1334 sx->next_addr = addr;
1336 addr->transport_return = PENDING_DEFER;
1337 addr->basic_errno = 0;
1341 /* Log temporary errors if there are more hosts to be tried.
1342 If not, log this last one in the == line. */
1344 if (sx->conn_args.host->next)
1345 if (LOGGING(outgoing_port))
1346 log_write(0, LOG_MAIN, "H=%s [%s]:%d %s", sx->conn_args.host->name,
1347 sx->conn_args.host->address,
1348 sx->port == PORT_NONE ? 25 : sx->port, addr->message);
1350 log_write(0, LOG_MAIN, "H=%s [%s]: %s", sx->conn_args.host->name,
1351 sx->conn_args.host->address, addr->message);
1353 #ifndef DISABLE_EVENT
1355 msg_event_raise(US"msg:rcpt:defer", addr);
1358 /* Do not put this message on the list of those waiting for specific
1359 hosts, as otherwise it is likely to be tried too often. */
1361 update_waiting = FALSE;
1363 /* Add a retry item for the address so that it doesn't get tried again
1364 too soon. If address_retry_include_sender is true, add the sender address
1365 to the retry key. */
1367 retry_add_item(addr,
1368 ob->address_retry_include_sender
1369 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
1370 : addr->address_retry_key,
1376 if (count && !(addr = addr->next))
1378 } /* Loop for next RCPT response */
1380 /* Update where to start at for the next block of responses, unless we
1381 have already handled all the addresses. */
1383 if (addr) sx->sync_addr = addr->next;
1385 /* Handle a response to DATA. If we have not had any good recipients, either
1386 previously or in this block, the response is ignored. */
1388 if (pending_DATA != 0)
1390 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1391 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1392 '3', ob->command_timeout))
1398 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1401 if (pending_DATA > 0 || (yield & 1) != 0)
1403 if (errno == 0 && sx->buffer[0] == '4')
1405 errno = ERRNO_DATA4XX;
1406 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1410 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1411 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1412 "is in use and there were no good recipients\n", msg);
1416 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1417 present) received 3xx. If any RCPTs were handled and yielded anything other
1418 than 4xx, yield will be set non-zero. */
1427 /* Try an authenticator's client entry */
1430 try_authenticator(smtp_context * sx, auth_instance * au)
1432 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1433 host_item * host = sx->conn_args.host; /* host to deliver to */
1436 /* Set up globals for error messages */
1438 authenticator_name = au->name;
1439 driver_srcfile = au->srcfile;
1440 driver_srcline = au->srcline;
1442 sx->outblock.authenticating = TRUE;
1443 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1444 sx->buffer, sizeof(sx->buffer));
1445 sx->outblock.authenticating = FALSE;
1446 driver_srcfile = authenticator_name = NULL; driver_srcline = 0;
1447 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n", au->name, rc);
1449 /* A temporary authentication failure must hold up delivery to
1450 this host. After a permanent authentication failure, we carry on
1451 to try other authentication methods. If all fail hard, try to
1452 deliver the message unauthenticated unless require_auth was set. */
1457 f.smtp_authenticated = TRUE; /* stops the outer loop */
1458 client_authenticator = au->name;
1459 if (au->set_client_id)
1460 client_authenticated_id = expand_string(au->set_client_id);
1463 /* Failure after writing a command */
1468 /* Failure after reading a response */
1471 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1472 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1473 au->name, host->name, host->address, sx->buffer);
1476 /* Failure by some other means. In effect, the authenticator
1477 decided it wasn't prepared to handle this case. Typically this
1478 is the result of "fail" in an expansion string. Do we need to
1479 log anything here? Feb 2006: a message is now put in the buffer
1480 if logging is required. */
1483 if (*sx->buffer != 0)
1484 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1485 "authentication H=%s [%s] %s", au->name, host->name,
1486 host->address, sx->buffer);
1489 /* Internal problem, message in buffer. */
1492 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1493 DEFER, FALSE, &sx->delivery_start);
1502 /* Do the client side of smtp-level authentication.
1505 sx smtp connection context
1507 sx->buffer should have the EHLO response from server (gets overwritten)
1510 OK Success, or failed (but not required): global "smtp_authenticated" set
1511 DEFER Failed authentication (and was required)
1512 ERROR Internal problem
1514 FAIL_SEND Failed communications - transmit
1519 smtp_auth(smtp_context * sx)
1521 host_item * host = sx->conn_args.host; /* host to deliver to */
1522 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1523 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1524 #ifndef DISABLE_PIPE_CONNECT
1525 unsigned short authbits = tls_out.active.sock >= 0
1526 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1528 uschar * fail_reason = US"server did not advertise AUTH support";
1530 f.smtp_authenticated = FALSE;
1531 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1534 regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
1536 /* Is the server offering AUTH? */
1540 #ifndef DISABLE_PIPE_CONNECT
1541 sx->early_pipe_active ? authbits
1544 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1547 uschar * names = NULL;
1548 expand_nmax = -1; /* reset */
1550 #ifndef DISABLE_PIPE_CONNECT
1551 if (!sx->early_pipe_active)
1553 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1555 /* Must not do this check until after we have saved the result of the
1556 regex match above as the check could be another RE. */
1558 if ( require_auth == OK
1559 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1561 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1562 fail_reason = US"no common mechanisms were found";
1564 #ifndef DISABLE_PIPE_CONNECT
1565 if (sx->early_pipe_active)
1567 /* Scan our authenticators (which support use by a client and were offered
1568 by the server (checked at cache-write time)), not suppressed by
1569 client_condition. If one is found, attempt to authenticate by calling its
1570 client function. We are limited to supporting up to 16 authenticator
1571 public-names by the number of bits in a short. */
1577 for (bitnum = 0, au = auths;
1578 !f.smtp_authenticated && au && bitnum < 16;
1579 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1581 if ( au->client_condition
1582 && !expand_check_condition(au->client_condition, au->name,
1583 US"client authenticator"))
1585 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1586 au->name, "client_condition is false");
1590 /* Found data for a listed mechanism. Call its client entry. Set
1591 a flag in the outblock so that data is overwritten after sending so
1592 that reflections don't show it. */
1594 fail_reason = US"authentication attempt(s) failed";
1596 if ((rc = try_authenticator(sx, au)) != OK)
1603 /* Scan the configured authenticators looking for one which is configured
1604 for use as a client, which is not suppressed by client_condition, and
1605 whose name matches an authentication mechanism supported by the server.
1606 If one is found, attempt to authenticate by calling its client function.
1609 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1614 || ( au->client_condition
1615 && !expand_check_condition(au->client_condition, au->name,
1616 US"client authenticator")))
1618 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1620 (au->client)? "client_condition is false" :
1621 "not configured as a client");
1625 /* Loop to scan supported server mechanisms */
1629 int len = Ustrlen(au->public_name);
1632 while (isspace(*p)) p++;
1634 if (strncmpic(au->public_name, p, len) != 0 ||
1635 (p[len] != 0 && !isspace(p[len])))
1637 while (*p != 0 && !isspace(*p)) p++;
1641 /* Found data for a listed mechanism. Call its client entry. Set
1642 a flag in the outblock so that data is overwritten after sending so
1643 that reflections don't show it. */
1645 fail_reason = US"authentication attempt(s) failed";
1647 if ((rc = try_authenticator(sx, au)) != OK)
1650 break; /* If not authenticated, try next authenticator */
1651 } /* Loop for scanning supported server mechanisms */
1652 } /* Loop for further authenticators */
1656 /* If we haven't authenticated, but are required to, give up. */
1658 if (require_auth == OK && !f.smtp_authenticated)
1660 #ifndef DISABLE_PIPE_CONNECT
1661 invalidate_ehlo_cache_entry(sx);
1663 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1664 string_sprintf("authentication required but %s", fail_reason), DEFER,
1665 FALSE, &sx->delivery_start);
1673 /* Construct AUTH appendix string for MAIL TO */
1676 sx context for smtp connection
1677 p point in sx->buffer to build string
1678 addrlist chain of potential addresses to deliver
1680 Globals f.smtp_authenticated
1681 client_authenticated_sender
1682 Return True on error, otherwise buffer has (possibly empty) terminated string
1686 smtp_mail_auth_str(smtp_context * sx, uschar * p, address_item * addrlist)
1688 smtp_transport_options_block * ob = sx->conn_args.ob;
1689 uschar * local_authenticated_sender = authenticated_sender;
1692 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n",
1693 authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1696 if (ob->authenticated_sender)
1698 uschar * new = expand_string(ob->authenticated_sender);
1701 if (!f.expand_string_forcedfail)
1703 uschar *message = string_sprintf("failed to expand "
1704 "authenticated_sender: %s", expand_string_message);
1705 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
1710 local_authenticated_sender = new;
1713 /* Add the authenticated sender address if present */
1715 if ( (f.smtp_authenticated || ob->authenticated_sender_force)
1716 && local_authenticated_sender)
1718 string_format_nt(p, sizeof(sx->buffer) - (p-sx->buffer), " AUTH=%s",
1719 auth_xtextencode(local_authenticated_sender,
1720 Ustrlen(local_authenticated_sender)));
1721 client_authenticated_sender = string_copy(local_authenticated_sender);
1731 typedef struct smtp_compare_s
1733 uschar * current_sender_address;
1734 struct transport_instance * tblock;
1738 /* Create a unique string that identifies this message, it is based on
1739 sender_address, helo_data and tls_certificate if enabled.
1743 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1745 address_item * addr1;
1746 uschar * if1 = US"";
1747 uschar * helo1 = US"";
1749 uschar * tlsc1 = US"";
1751 uschar * save_sender_address = sender_address;
1752 uschar * local_identity = NULL;
1753 smtp_transport_options_block * ob = SOB tblock->options_block;
1755 sender_address = sender;
1757 addr1 = deliver_make_addr (sender, TRUE);
1758 deliver_set_expansions(addr1);
1761 if1 = expand_string(ob->interface);
1764 helo1 = expand_string(ob->helo_data);
1767 if (ob->tls_certificate)
1768 tlsc1 = expand_string(ob->tls_certificate);
1769 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1771 local_identity = string_sprintf ("%s^%s", if1, helo1);
1774 deliver_set_expansions(NULL);
1775 sender_address = save_sender_address;
1777 return local_identity;
1782 /* This routine is a callback that is called from transport_check_waiting.
1783 This function will evaluate the incoming message versus the previous
1784 message. If the incoming message is using a different local identity then
1785 we will veto this new message. */
1788 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1790 uschar * message_local_identity,
1791 * current_local_identity,
1792 * new_sender_address;
1794 current_local_identity =
1795 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1797 if (!(new_sender_address = spool_sender_from_msgid(message_id)))
1801 message_local_identity =
1802 smtp_local_identity(new_sender_address, s_compare->tblock);
1804 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1810 ehlo_response(uschar * buf, unsigned checks)
1812 PCRE2_SIZE bsize = Ustrlen(buf);
1813 pcre2_match_data * md = pcre2_match_data_create(1, pcre_gen_ctx);
1815 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1818 if ( checks & OPTION_TLS
1819 && pcre2_match(regex_STARTTLS,
1820 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1822 checks &= ~OPTION_TLS;
1824 if ( checks & OPTION_IGNQ
1825 && pcre2_match(regex_IGNOREQUOTA,
1826 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1827 checks &= ~OPTION_IGNQ;
1829 if ( checks & OPTION_CHUNKING
1830 && pcre2_match(regex_CHUNKING,
1831 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1832 checks &= ~OPTION_CHUNKING;
1834 #ifndef DISABLE_PRDR
1835 if ( checks & OPTION_PRDR
1836 && pcre2_match(regex_PRDR,
1837 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1839 checks &= ~OPTION_PRDR;
1842 if ( checks & OPTION_UTF8
1843 && pcre2_match(regex_UTF8,
1844 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1846 checks &= ~OPTION_UTF8;
1848 if ( checks & OPTION_DSN
1849 && pcre2_match(regex_DSN,
1850 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1851 checks &= ~OPTION_DSN;
1853 if ( checks & OPTION_PIPE
1854 && pcre2_match(regex_PIPELINING,
1855 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1856 checks &= ~OPTION_PIPE;
1858 if ( checks & OPTION_SIZE
1859 && pcre2_match(regex_SIZE,
1860 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1861 checks &= ~OPTION_SIZE;
1863 #ifndef DISABLE_PIPE_CONNECT
1864 if ( checks & OPTION_EARLY_PIPE
1865 && pcre2_match(regex_EARLY_PIPE,
1866 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_mtc_ctx) < 0)
1868 checks &= ~OPTION_EARLY_PIPE;
1870 pcre2_match_data_free(md);
1871 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1877 /* Callback for emitting a BDAT data chunk header.
1879 If given a nonzero size, first flush any buffered SMTP commands
1880 then emit the command.
1882 Reap previous SMTP command responses if requested, and always reap
1883 the response from a previous BDAT command.
1886 tctx transport context
1887 chunk_size value for SMTP BDAT command
1889 tc_chunk_last add LAST option to SMTP BDAT command
1890 tc_reap_prev reap response to previous SMTP commands
1894 DEFER TLS error on first read (EHLO-resp); errno set
1898 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1901 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1902 smtp_context * sx = tctx->smtp_context;
1906 /* Write SMTP chunk header command. If not reaping responses, note that
1907 there may be more writes (like, the chunk data) done soon. */
1911 #ifndef DISABLE_PIPE_CONNECT
1912 BOOL new_conn = !!(sx->outblock.conn_args);
1914 if((cmd_count = smtp_write_command(sx,
1915 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1916 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1917 ) < 0) return ERROR;
1918 if (flags & tc_chunk_last)
1919 data_command = string_copy(big_buffer); /* Save for later error message */
1920 #ifndef DISABLE_PIPE_CONNECT
1921 /* That command write could have been the one that made the connection.
1922 Copy the fd from the client conn ctx (smtp transport specific) to the
1923 generic transport ctx. */
1926 tctx->u.fd = sx->outblock.cctx->sock;
1930 prev_cmd_count = cmd_count += sx->cmd_count;
1932 /* Reap responses for any previous, but not one we just emitted */
1936 if (sx->pending_BDAT)
1939 if (flags & tc_reap_prev && prev_cmd_count > 0)
1941 DEBUG(D_transport) debug_printf("look for %d responses"
1942 " for previous pipelined cmds\n", prev_cmd_count);
1944 switch(sync_responses(sx, prev_cmd_count, 0))
1946 case 1: /* 2xx (only) => OK */
1947 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1948 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1949 case 0: break; /* No 2xx or 5xx, but no probs */
1951 case -5: errno = ERRNO_TLSFAILURE;
1953 #ifndef DISABLE_PIPE_CONNECT
1954 case -4: /* non-2xx for pipelined banner or EHLO */
1956 case -1: /* Timeout on RCPT */
1957 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1960 if (!sx->pending_BDAT)
1961 pipelining_active = FALSE;
1964 /* Reap response for an outstanding BDAT */
1966 if (sx->pending_BDAT)
1968 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1970 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
1971 ob->command_timeout))
1973 if (errno == 0 && sx->buffer[0] == '4')
1975 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1976 sx->addrlist->more_errno |=
1977 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1982 sx->pending_BDAT = FALSE;
1983 pipelining_active = FALSE;
1985 else if (chunk_size > 0)
1986 sx->pending_BDAT = TRUE;
1989 sx->cmd_count = cmd_count;
1995 /*************************************************
1996 * Make connection for given message *
1997 *************************************************/
2001 sx connection context
2002 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2003 a second attempt after TLS initialization fails
2005 Returns: OK - the connection was made and the delivery attempted;
2006 fd is set in the conn context, tls_out set up.
2007 DEFER - the connection could not be made, or something failed
2008 while setting up the SMTP session, or there was a
2009 non-message-specific error, such as a timeout.
2010 ERROR - helo_data or add_headers or authenticated_sender is
2011 specified for this transport, and the string failed
2015 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
2017 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
2018 BOOL pass_message = FALSE;
2019 uschar * message = NULL;
2022 uschar * tls_errstr;
2025 /* Many lines of clearing individual elements of *sx that used to
2026 be here have been replaced by a full memset to zero (de41aff051).
2027 There are two callers, this file and verify.c . Now we only set
2028 up nonzero elements. */
2030 sx->conn_args.ob = ob;
2032 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
2033 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
2034 sx->send_rset = TRUE;
2035 sx->send_quit = TRUE;
2036 sx->setting_up = TRUE;
2038 sx->dsn_all_lasthop = TRUE;
2041 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
2044 if ((sx->max_mail = sx->conn_args.tblock->connection_max_messages) == 0) sx->max_mail = 999999;
2045 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
2046 sx->igquotstr = US"";
2047 if (!sx->helo_data) sx->helo_data = ob->helo_data;
2049 smtp_command = US"initial connection";
2051 /* Set up the buffer for reading SMTP response packets. */
2053 sx->inblock.buffer = sx->inbuffer;
2054 sx->inblock.buffersize = sizeof(sx->inbuffer);
2055 sx->inblock.ptr = sx->inbuffer;
2056 sx->inblock.ptrend = sx->inbuffer;
2058 /* Set up the buffer for holding SMTP commands while pipelining */
2060 sx->outblock.buffer = sx->outbuffer;
2061 sx->outblock.buffersize = sizeof(sx->outbuffer);
2062 sx->outblock.ptr = sx->outbuffer;
2064 /* Reset the parameters of a TLS session. */
2067 tls_out.cipher = NULL; /* the one we may use for this transport */
2068 tls_out.ourcert = NULL;
2069 tls_out.peercert = NULL;
2070 tls_out.peerdn = NULL;
2074 tls_out.ocsp = OCSP_NOT_REQ;
2075 #ifndef DISABLE_TLS_RESUME
2076 tls_out.resumption = 0;
2080 /* Flip the legacy TLS-related variables over to the outbound set in case
2081 they're used in the context of the transport. Don't bother resetting
2082 afterward (when being used by a transport) as we're in a subprocess.
2083 For verify, unflipped once the callout is dealt with */
2085 tls_modify_variables(&tls_out);
2090 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
2091 DEFER, FALSE, &sx->delivery_start);
2096 /* If we have a proxied TLS connection, check usability for this message */
2098 if (continue_hostname && continue_proxy_cipher)
2101 const uschar * sni = US"";
2103 # ifdef SUPPORT_DANE
2104 /* Check if the message will be DANE-verified; if so force its SNI */
2106 tls_out.dane_verified = FALSE;
2107 smtp_port_for_connect(sx->conn_args.host, sx->port);
2108 if ( sx->conn_args.host->dnssec == DS_YES
2109 && ( sx->dane_required
2110 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2112 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2114 case OK: sx->conn_args.dane = TRUE;
2115 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2116 ob->tls_sni = sx->conn_args.host->name; /* force SNI */
2118 case FAIL_FORCED: break;
2119 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2120 string_sprintf("DANE error: tlsa lookup %s",
2122 rc, FALSE, &sx->delivery_start);
2123 # ifndef DISABLE_EVENT
2124 (void) event_raise(sx->conn_args.tblock->event_action,
2125 US"dane:fail", sx->dane_required
2126 ? US"dane-required" : US"dnssec-invalid",
2133 /* If the SNI or the DANE status required for the new message differs from the
2134 existing conn drop the connection to force a new one. */
2136 if (ob->tls_sni && !(sni = expand_cstring(ob->tls_sni)))
2137 log_write(0, LOG_MAIN|LOG_PANIC,
2138 "<%s>: failed to expand transport's tls_sni value: %s",
2139 sx->addrlist->address, expand_string_message);
2141 # ifdef SUPPORT_DANE
2142 if ( (continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni)
2143 && continue_proxy_dane == sx->conn_args.dane)
2145 tls_out.sni = US sni;
2146 if ((tls_out.dane_verified = continue_proxy_dane))
2147 sx->conn_args.host->dnssec = DS_YES;
2150 if ((continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni))
2151 tls_out.sni = US sni;
2156 debug_printf("Closing proxied-TLS connection due to SNI mismatch\n");
2158 smtp_debug_cmd(US"QUIT", 0);
2159 write(0, "QUIT\r\n", 6);
2161 continue_hostname = continue_proxy_cipher = NULL;
2162 f.continue_more = FALSE;
2163 continue_sequence = 1; /* Unfortunately, this process cannot affect success log
2164 which is done by delivery proc. Would have to pass this
2165 back through reporting pipe. */
2168 #endif /*!DISABLE_TLS*/
2170 /* Make a connection to the host if this isn't a continued delivery, and handle
2171 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2172 specially so they can be identified for retries. */
2174 if (!continue_hostname)
2177 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2179 /* Arrange to report to calling process this is a new connection */
2181 clearflag(sx->first_addr, af_cont_conn);
2182 setflag(sx->first_addr, af_new_conn);
2184 /* Get the actual port the connection will use, into sx->conn_args.host */
2186 smtp_port_for_connect(sx->conn_args.host, sx->port);
2189 /* Do TLSA lookup for DANE */
2191 tls_out.dane_verified = FALSE;
2192 tls_out.tlsa_usage = 0;
2194 if (sx->conn_args.host->dnssec == DS_YES)
2197 if( sx->dane_required
2198 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2200 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2202 case OK: sx->conn_args.dane = TRUE;
2203 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2204 ob->tls_sni = sx->conn_args.host->name; /* force SNI */
2206 case FAIL_FORCED: break;
2207 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2208 string_sprintf("DANE error: tlsa lookup %s",
2210 rc, FALSE, &sx->delivery_start);
2211 # ifndef DISABLE_EVENT
2212 (void) event_raise(sx->conn_args.tblock->event_action,
2213 US"dane:fail", sx->dane_required
2214 ? US"dane-required" : US"dnssec-invalid",
2220 else if (sx->dane_required)
2222 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2223 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2224 FAIL, FALSE, &sx->delivery_start);
2225 # ifndef DISABLE_EVENT
2226 (void) event_raise(sx->conn_args.tblock->event_action,
2227 US"dane:fail", US"dane-required", NULL);
2234 /* Make the TCP connection */
2236 sx->cctx.tls_ctx = NULL;
2237 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2238 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2239 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom =
2241 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2242 #ifndef DISABLE_CLIENT_CMD_LOG
2243 client_cmd_log = NULL;
2246 #ifndef DISABLE_PIPE_CONNECT
2247 if ( verify_check_given_host(CUSS &ob->hosts_pipe_connect,
2248 sx->conn_args.host) == OK)
2250 /* We don't find out the local ip address until the connect, so if
2251 the helo string might use it avoid doing early-pipelining. */
2254 || sx->conn_args.interface
2255 || !Ustrstr(sx->helo_data, "$sending_ip_address")
2256 || Ustrstr(sx->helo_data, "def:sending_ip_address")
2259 sx->early_pipe_ok = TRUE;
2260 if ( read_ehlo_cache_entry(sx)
2261 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2264 debug_printf("Using cached cleartext PIPECONNECT\n");
2265 sx->early_pipe_active = TRUE;
2266 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2269 else DEBUG(D_transport)
2270 debug_printf("helo needs $sending_ip_address; avoid early-pipelining\n");
2273 if (sx->early_pipe_active)
2275 sx->outblock.conn_args = &sx->conn_args;
2276 (void) smtp_boundsock(&sx->conn_args);
2281 blob lazy_conn = {.data = NULL};
2282 /* For TLS-connect, a TFO lazy-connect is useful since the Client Hello
2283 can go on the TCP SYN. */
2285 if ((sx->cctx.sock = smtp_connect(&sx->conn_args,
2286 sx->smtps ? &lazy_conn : NULL)) < 0)
2288 set_errno_nohost(sx->addrlist,
2289 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2290 sx->verify ? US strerror(errno) : NULL,
2291 DEFER, FALSE, &sx->delivery_start);
2292 sx->send_quit = FALSE;
2296 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2300 /* Expand the greeting message while waiting for the initial response. (Makes
2301 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2302 delayed till here so that $sending_ip_address and $sending_port are set.
2303 Those will be known even for a TFO lazy-connect, having been set by the bind().
2304 For early-pipe, we are ok if binding to a local interface; otherwise (if
2305 $sending_ip_address is seen in helo_data) we disabled early-pipe above. */
2308 if (!(sx->helo_data = expand_string(sx->helo_data)))
2310 log_write(0, LOG_MAIN|LOG_PANIC,
2311 "<%s>: failed to expand transport's helo_data value for callout: %s",
2312 sx->addrlist->address, expand_string_message);
2317 expand_string_message = NULL;
2318 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2319 &expand_string_message)),
2320 expand_string_message)
2322 log_write(0, LOG_MAIN|LOG_PANIC,
2323 "<%s>: failed to expand transport's helo_data value for callout: %s",
2324 sx->addrlist->address, expand_string_message);
2326 sx->helo_data = NULL;
2330 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2331 is nevertheless a reasonably clean way of programming this kind of logic,
2332 where you want to escape on any error. */
2336 #ifndef DISABLE_PIPE_CONNECT
2337 if (sx->early_pipe_active)
2339 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2340 sx->outblock.cmd_count = 1;
2345 if (!smtp_reap_banner(sx))
2346 goto RESPONSE_FAILED;
2349 #ifndef DISABLE_EVENT
2352 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2353 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2354 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer, NULL);
2357 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2358 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2359 DEFER, FALSE, &sx->delivery_start);
2366 /* Now check if the helo_data expansion went well, and sign off cleanly if
2371 message = string_sprintf("failed to expand helo_data: %s",
2372 expand_string_message);
2373 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2379 /** Debugging without sending a message
2380 sx->addrlist->transport_return = DEFER;
2384 /* Errors that occur after this point follow an SMTP command, which is
2385 left in big_buffer by smtp_write_command() for use in error messages. */
2387 smtp_command = big_buffer;
2389 /* Tell the remote who we are...
2391 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2392 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2393 greeting is of this form. The assumption was that the far end supports it
2394 properly... but experience shows that there are some that give 5xx responses,
2395 even though the banner includes "ESMTP" (there's a bloody-minded one that
2396 says "ESMTP not spoken here"). Cope with that case.
2398 September 2000: Time has passed, and it seems reasonable now to always send
2399 EHLO at the start. It is also convenient to make the change while installing
2402 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2403 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2404 would be no way to send out the mails, so there is now a host list
2405 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2406 PIPELINING problem as well. Maybe it can also be useful to cure other
2407 problems with broken servers.
2409 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2410 Then somebody tried it with a Microsoft mailer... It seems that all other
2411 mailers use upper case for some reason (the RFC is quite clear about case
2412 independence) so, for peace of mind, I gave in. */
2414 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2416 /* Alas; be careful, since this goto is not an error-out, so conceivably
2417 we might set data between here and the target which we assume to exist
2418 and be usable. I can see this coming back to bite us. */
2422 smtp_peer_options |= OPTION_TLS;
2423 suppress_tls = FALSE;
2424 ob->tls_tempfail_tryclear = FALSE;
2425 smtp_command = US"SSL-on-connect";
2432 if (smtp_write_command(sx,
2433 #ifndef DISABLE_PIPE_CONNECT
2434 sx->early_pipe_active ? SCMD_BUFFER :
2437 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2439 sx->esmtp_sent = TRUE;
2441 #ifndef DISABLE_PIPE_CONNECT
2442 if (sx->early_pipe_active)
2444 sx->pending_EHLO = TRUE;
2446 /* If we have too many authenticators to handle and might need to AUTH
2447 for this transport, pipeline no further as we will need the
2448 list of auth methods offered. Reap the banner and EHLO. */
2450 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2451 && f.smtp_in_early_pipe_no_auth)
2453 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2454 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2456 if (sync_responses(sx, 2, 0) != 0)
2459 debug_printf("failed reaping pipelined cmd responses\n");
2460 goto RESPONSE_FAILED;
2462 sx->early_pipe_active = FALSE;
2467 if (!smtp_reap_ehlo(sx))
2468 goto RESPONSE_FAILED;
2472 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2474 #ifndef DISABLE_PIPE_CONNECT
2475 if (!sx->early_pipe_active)
2480 int n = sizeof(sx->buffer);
2481 uschar * rsp = sx->buffer;
2483 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer) + 1) < sizeof(sx->buffer)/2)
2484 { rsp = sx->buffer + n; n = sizeof(sx->buffer) - n; }
2486 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2488 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2489 #ifdef EXPERIMENTAL_DSN_INFO
2490 sx->helo_response = string_copy(rsp);
2494 /* Handle special logging for a closed connection after HELO
2495 when had previously sent EHLO */
2497 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2499 errno = ERRNO_SMTPCLOSED;
2500 goto EHLOHELO_FAILED;
2502 memmove(sx->buffer, rsp, Ustrlen(rsp));
2503 goto RESPONSE_FAILED;
2507 if (sx->esmtp || sx->lmtp)
2509 #ifndef DISABLE_PIPE_CONNECT
2510 if (!sx->early_pipe_active)
2513 sx->peer_offered = ehlo_response(sx->buffer,
2514 OPTION_TLS /* others checked later */
2515 #ifndef DISABLE_PIPE_CONNECT
2516 | (sx->early_pipe_ok
2518 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2527 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2528 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2530 ehlo_response_limits_read(sx);
2531 ehlo_response_limits_apply(sx);
2534 #ifndef DISABLE_PIPE_CONNECT
2535 if (sx->early_pipe_ok)
2537 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2539 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2540 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2542 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2543 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2544 write_ehlo_cache_entry(sx);
2550 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2553 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2558 /* For continuing deliveries down the same channel, having re-exec'd the socket
2559 is the standard input; for a socket held open from verify it is recorded
2560 in the cutthrough context block. Either way we don't need to redo EHLO here
2561 (but may need to do so for TLS - see below).
2562 Set up the pointer to where subsequent commands will be left, for
2563 error messages. Note that smtp_peer_options will have been
2564 set from the command line if they were set in the process that passed the
2567 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2568 as the continue goes via transport_pass_socket() and doublefork and exec.
2569 It does not wait. Unclear how we keep separate host's responses
2570 separate - we could match up by host ip+port as a bodge. */
2574 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2576 sx->cctx = cutthrough.cctx;
2577 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2581 sx->cctx.sock = 0; /* stdin */
2582 sx->cctx.tls_ctx = NULL;
2583 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2585 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2586 smtp_command = big_buffer;
2587 sx->peer_offered = smtp_peer_options;
2588 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2589 /* Limits passed by cmdline over exec. */
2590 ehlo_limits_apply(sx,
2591 sx->peer_limit_mail = continue_limit_mail,
2592 sx->peer_limit_rcpt = continue_limit_rcpt,
2593 sx->peer_limit_rcptdom = continue_limit_rcptdom);
2595 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2597 /* For a continued connection with TLS being proxied for us, or a
2598 held-open verify connection with TLS, nothing more to do. */
2600 if ( continue_proxy_cipher
2601 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2602 && cutthrough.is_tls)
2605 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2606 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2607 continue_proxy_cipher ? "proxied" : "verify conn with");
2610 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2613 /* If TLS is available on this connection, whether continued or not, attempt to
2614 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2615 send another EHLO - the server may give a different answer in secure mode. We
2616 use a separate buffer for reading the response to STARTTLS so that if it is
2617 negative, the original EHLO data is available for subsequent analysis, should
2618 the client not be required to use TLS. If the response is bad, copy the buffer
2619 for error analysis. */
2622 if ( smtp_peer_options & OPTION_TLS
2624 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2626 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2629 uschar buffer2[4096];
2631 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2634 #ifndef DISABLE_PIPE_CONNECT
2635 /* If doing early-pipelining reap the banner and EHLO-response but leave
2636 the response for the STARTTLS we just sent alone. On fail, assume wrong
2637 cached capability and retry with the pipelining disabled. */
2639 if (sx->early_pipe_active && sync_responses(sx, 2, 0) != 0)
2642 debug_printf("failed reaping pipelined cmd responses\n");
2643 close(sx->cctx.sock);
2645 sx->early_pipe_active = FALSE;
2646 goto PIPE_CONNECT_RETRY;
2650 /* If there is an I/O error, transmission of this message is deferred. If
2651 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2652 false, we also defer. However, if there is a temporary rejection of STARTTLS
2653 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2654 STARTTLS, we carry on. This means we will try to send the message in clear,
2655 unless the host is in hosts_require_tls (tested below). */
2657 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2661 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2664 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2665 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2666 goto RESPONSE_FAILED;
2670 /* STARTTLS accepted: try to negotiate a TLS session. */
2675 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2677 /* TLS negotiation failed; give an error. From outside, this function may
2678 be called again to try in clear on a new connection, if the options permit
2679 it for this host. */
2681 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2683 # ifdef SUPPORT_DANE
2684 if (sx->conn_args.dane)
2686 log_write(0, LOG_MAIN,
2687 "DANE attempt failed; TLS connection to %s [%s]: %s",
2688 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2689 # ifndef DISABLE_EVENT
2690 (void) event_raise(sx->conn_args.tblock->event_action,
2691 US"dane:fail", US"validation-failure", NULL); /* could do with better detail */
2696 errno = ERRNO_TLSFAILURE;
2697 message = string_sprintf("TLS session: %s", tls_errstr);
2698 sx->send_quit = FALSE;
2701 sx->send_tlsclose = TRUE;
2703 /* TLS session is set up. Check the inblock fill level. If there is
2704 content then as we have not yet done a tls read it must have arrived before
2705 the TLS handshake, in-clear. That violates the sync requirement of the
2706 STARTTLS RFC, so fail. */
2708 if (sx->inblock.ptr != sx->inblock.ptrend)
2712 int i = sx->inblock.ptrend - sx->inblock.ptr;
2713 debug_printf("unused data in input buffer after ack for STARTTLS:\n"
2715 i > 100 ? 100 : i, sx->inblock.ptr, i > 100 ? "..." : "");
2717 tls_errstr = US"synch error before connect";
2718 goto TLS_CONN_FAILED;
2721 smtp_peer_options_wrap = smtp_peer_options;
2722 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2723 if (addr->transport_return == PENDING_DEFER)
2725 addr->cipher = tls_out.cipher;
2726 addr->ourcert = tls_out.ourcert;
2727 addr->peercert = tls_out.peercert;
2728 addr->peerdn = tls_out.peerdn;
2729 addr->ocsp = tls_out.ocsp;
2730 addr->tlsver = tls_out.ver;
2735 /* if smtps, we'll have smtp_command set to something else; always safe to
2737 smtp_command = big_buffer;
2739 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2740 helo_data is null, we are dealing with a connection that was passed from
2741 another process, and so we won't have expanded helo_data above. We have to
2742 expand it here. $sending_ip_address and $sending_port are set up right at the
2743 start of the Exim process (in exim.c). */
2745 if (tls_out.active.sock >= 0)
2747 uschar * greeting_cmd;
2749 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2751 uschar *message = string_sprintf("failed to expand helo_data: %s",
2752 expand_string_message);
2753 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2758 #ifndef DISABLE_PIPE_CONNECT
2759 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2760 We're unlikely to get the group sent and delivered before the server sends its
2761 banner, but it's still worth sending as a group.
2762 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2765 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2767 sx->peer_offered = sx->ehlo_resp.crypted_features;
2768 if ((sx->early_pipe_active =
2769 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2770 DEBUG(D_transport) debug_printf("Using cached crypted PIPECONNECT\n");
2773 #ifdef EXPERIMMENTAL_ESMTP_LIMITS
2774 /* As we are about to send another EHLO, forget any LIMITS received so far. */
2775 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom = 0;
2776 if ((sx->max_mail = sx->conn_args.tblock->connection_max_message) == 0) sx->max_mail = 999999;
2777 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
2778 sx->single_rcpt_domain = FALSE;
2781 /* For SMTPS we need to wait for the initial OK response. */
2783 #ifndef DISABLE_PIPE_CONNECT
2784 if (sx->early_pipe_active)
2786 sx->pending_BANNER = TRUE;
2787 sx->outblock.cmd_count = 1;
2791 if (!smtp_reap_banner(sx))
2792 goto RESPONSE_FAILED;
2795 greeting_cmd = US"LHLO";
2797 greeting_cmd = US"EHLO";
2800 greeting_cmd = US"HELO";
2802 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2805 if (smtp_write_command(sx,
2806 #ifndef DISABLE_PIPE_CONNECT
2807 sx->early_pipe_active ? SCMD_BUFFER :
2810 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2813 #ifndef DISABLE_PIPE_CONNECT
2814 if (sx->early_pipe_active)
2815 sx->pending_EHLO = TRUE;
2819 if (!smtp_reap_ehlo(sx))
2822 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2823 cert late, under TLS1.3 - which means here; the first time we try to
2824 receive crypted data. Treat it as if it was a connect-time failure.
2825 See also the early-pipe equivalent... which will be hard; every call
2826 to sync_responses will need to check the result.
2827 It would be nicer to have GnuTLS check the cert during the handshake.
2828 Can it do that, with all the flexibility we need? */
2830 tls_errstr = US"error on first read";
2831 goto TLS_CONN_FAILED;
2834 goto RESPONSE_FAILED;
2836 smtp_peer_options = 0;
2840 /* If the host is required to use a secure channel, ensure that we
2844 # ifdef SUPPORT_DANE
2845 || sx->conn_args.dane
2847 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2850 errno = ERRNO_TLSREQUIRED;
2851 message = string_sprintf("a TLS session is required, but %s",
2852 smtp_peer_options & OPTION_TLS
2853 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2854 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2855 if (sx->conn_args.dane)
2856 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2857 smtp_peer_options & OPTION_TLS
2858 ? US"validation-failure" /* could do with better detail */
2859 : US"starttls-not-supported",
2864 #endif /*DISABLE_TLS*/
2866 /* If TLS is active, we have just started it up and re-done the EHLO command,
2867 so its response needs to be analyzed. If TLS is not active and this is a
2868 continued session down a previously-used socket, we haven't just done EHLO, so
2871 if ( !continue_hostname
2873 || tls_out.active.sock >= 0
2877 if (sx->esmtp || sx->lmtp)
2879 #ifndef DISABLE_PIPE_CONNECT
2880 if (!sx->early_pipe_active)
2883 sx->peer_offered = ehlo_response(sx->buffer,
2885 #ifndef DISABLE_PIPE_CONNECT
2886 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2887 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2888 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2889 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2893 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2896 # ifdef SUPPORT_I18N
2897 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2898 /*XXX if we hand peercaps on to continued-conn processes,
2899 must not depend on this addr */
2903 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2906 #ifndef DISABLE_PIPE_CONNECT
2907 if (tls_out.active.sock >= 0)
2908 sx->ehlo_resp.crypted_features = sx->peer_offered;
2911 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2912 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2914 ehlo_response_limits_read(sx);
2915 ehlo_response_limits_apply(sx);
2920 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2921 lmtp_ignore_quota option was set. */
2923 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2925 /* If the response to EHLO specified support for the SIZE parameter, note
2926 this, provided size_addition is non-negative. */
2928 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2930 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2931 the current host, esmtp will be false, so PIPELINING can never be used. If
2932 the current host matches hosts_avoid_pipelining, don't do it. */
2934 if ( sx->peer_offered & OPTION_PIPE
2935 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2936 smtp_peer_options |= OPTION_PIPE;
2938 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2939 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2941 if ( sx->peer_offered & OPTION_CHUNKING
2942 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) == OK)
2943 smtp_peer_options |= OPTION_CHUNKING;
2945 if (smtp_peer_options & OPTION_CHUNKING)
2946 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2948 #ifndef DISABLE_PRDR
2949 if ( sx->peer_offered & OPTION_PRDR
2950 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) == OK)
2951 smtp_peer_options |= OPTION_PRDR;
2953 if (smtp_peer_options & OPTION_PRDR)
2954 DEBUG(D_transport) debug_printf("PRDR usable\n");
2957 /* Note if the server supports DSN */
2958 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2959 DEBUG(D_transport) debug_printf("%susing DSN\n",
2960 sx->peer_offered & OPTION_DSN ? "" : "not ");
2962 #ifndef DISABLE_PIPE_CONNECT
2963 if ( sx->early_pipe_ok
2964 && !sx->early_pipe_active
2965 && tls_out.active.sock >= 0
2966 && smtp_peer_options & OPTION_PIPE
2967 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
2968 & OPTION_EARLY_PIPE)
2970 DEBUG(D_transport) debug_printf("PIPECONNECT usable in future for this IP\n");
2971 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
2972 write_ehlo_cache_entry(sx);
2976 /* Note if the response to EHLO specifies support for the AUTH extension.
2977 If it has, check that this host is one we want to authenticate to, and do
2978 the business. The host name and address must be available when the
2979 authenticator's client driver is running. */
2981 switch (yield = smtp_auth(sx))
2983 default: goto SEND_QUIT;
2985 case FAIL_SEND: goto SEND_FAILED;
2986 case FAIL: goto RESPONSE_FAILED;
2990 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2992 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2993 message-specific. */
2995 sx->setting_up = FALSE;
2998 if (sx->addrlist->prop.utf8_msg)
3002 /* If the transport sets a downconversion mode it overrides any set by ACL
3005 if ((s = ob->utf8_downconvert))
3007 if (!(s = expand_string(s)))
3009 message = string_sprintf("failed to expand utf8_downconvert: %s",
3010 expand_string_message);
3011 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
3017 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
3018 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3020 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
3021 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3023 case '-': if (s[1] == '1')
3025 sx->addrlist->prop.utf8_downcvt = FALSE;
3026 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
3032 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
3033 && !sx->addrlist->prop.utf8_downcvt_maybe;
3034 DEBUG(D_transport) if (!sx->utf8_needed)
3035 debug_printf("utf8: %s downconvert\n",
3036 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
3039 /* If this is an international message we need the host to speak SMTPUTF8 */
3040 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
3042 errno = ERRNO_UTF8_FWD;
3043 goto RESPONSE_FAILED;
3045 #endif /*SUPPORT_I18N*/
3054 if (errno == ECONNREFUSED) /* first-read error on a TFO conn */
3056 /* There is a testing facility for simulating a connection timeout, as I
3057 can't think of any other way of doing this. It converts a connection
3058 refused into a timeout if the timeout is set to 999999. This is done for
3059 a 3whs connection in ip_connect(), but a TFO connection does not error
3060 there - instead it gets ECONNREFUSED on the first data read. Tracking
3061 that a TFO really was done is too hard, or we would set a
3062 sx->pending_conn_done bit and test that in smtp_reap_banner() and
3063 smtp_reap_ehlo(). That would let us also add the conn-timeout to the
3066 if (f.running_in_test_harness && ob->connect_timeout == 999999)
3068 set_errno_nohost(sx->addrlist,
3069 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
3070 sx->verify ? US strerror(errno) : NULL,
3071 DEFER, FALSE, &sx->delivery_start);
3072 sx->send_quit = FALSE;
3076 /* really an error on an SMTP read */
3078 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
3079 sx->buffer, &code, &message, &pass_message);
3085 message = US string_sprintf("smtp send to %s [%s] failed: %s",
3086 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
3087 sx->send_quit = FALSE;
3093 message = string_sprintf("Remote host closed connection in response to %s"
3094 " (EHLO response was: %s)", smtp_command, sx->buffer);
3095 sx->send_quit = FALSE;
3099 /* This label is jumped to directly when a TLS negotiation has failed,
3100 or was not done for a host for which it is required. Values will be set
3101 in message and errno, and setting_up will always be true. Treat as
3102 a temporary error. */
3106 code = '4', yield = DEFER;
3110 /* The failure happened while setting up the call; see if the failure was
3111 a 5xx response (this will either be on connection, or following HELO - a 5xx
3112 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
3113 fail all addresses, as this host is never going to accept them. For other
3114 errors during setting up (timeouts or whatever), defer all addresses, and
3115 yield DEFER, so that the host is not tried again for a while.
3117 XXX This peeking for another host feels like a layering violation. We want
3118 to note the host as unusable, but down here we shouldn't know if this was
3119 the last host to try for the addr(list). Perhaps the upper layer should be
3120 the one to do set_errno() ? The problem is that currently the addr is where
3121 errno etc. are stashed, but until we run out of hosts to try the errors are
3122 host-specific. Maybe we should enhance the host_item definition? */
3125 sx->ok = FALSE; /* For when reached by GOTO */
3126 set_errno(sx->addrlist, errno, message,
3127 sx->conn_args.host->next
3131 || errno == ERRNO_UTF8_FWD
3135 errno == ECONNREFUSED ? NULL : sx->conn_args.host,
3136 #ifdef EXPERIMENTAL_DSN_INFO
3137 sx->smtp_greeting, sx->helo_response,
3139 &sx->delivery_start);
3146 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
3149 if (sx->cctx.tls_ctx)
3151 if (sx->send_tlsclose)
3153 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
3154 sx->send_tlsclose = FALSE;
3156 sx->cctx.tls_ctx = NULL;
3160 /* Close the socket, and return the appropriate value, first setting
3161 works because the NULL setting is passed back to the calling process, and
3162 remote_max_parallel is forced to 1 when delivering over an existing connection,
3165 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3168 shutdown(sx->cctx.sock, SHUT_WR);
3169 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
3170 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
3171 i--; /* drain socket */
3172 sx->send_quit = FALSE;
3174 (void)close(sx->cctx.sock);
3177 #ifndef DISABLE_EVENT
3178 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL, NULL);
3181 smtp_debug_cmd_report();
3182 continue_transport = NULL;
3183 continue_hostname = NULL;
3190 /* Create the string of options that will be appended to the MAIL FROM:
3191 in the connection context buffer */
3194 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
3196 uschar * p = sx->buffer;
3197 address_item * addr;
3202 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
3203 send it, adding something to the message size to allow for imprecision
3204 and things that get added en route. Exim keeps the number of lines
3205 in a message, so we can give an accurate value for the original message, but we
3206 need some additional to handle added headers. (Double "." characters don't get
3207 included in the count.) */
3209 if ( message_size > 0
3210 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
3212 /*XXX problem here under spool_files_wireformat?
3213 Or just forget about lines? Or inflate by a fixed proportion? */
3215 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
3219 #ifndef DISABLE_PRDR
3220 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
3223 sx->prdr_active = FALSE;
3224 if (smtp_peer_options & OPTION_PRDR)
3225 for (address_item * addr = addrlist; addr; addr = addr->next)
3226 if (addr->transport_return == PENDING_DEFER)
3228 for (addr = addr->next; addr; addr = addr->next)
3229 if (addr->transport_return == PENDING_DEFER)
3230 { /* at least two recipients to send */
3231 sx->prdr_active = TRUE;
3232 sprintf(CS p, " PRDR"); p += 5;
3240 /* If it supports internationalised messages, and this meesage need that,
3243 if ( sx->peer_offered & OPTION_UTF8
3244 && addrlist->prop.utf8_msg
3245 && !addrlist->prop.utf8_downcvt
3247 Ustrcpy(p, US" SMTPUTF8"), p += 9;
3250 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3251 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3252 addr && address_count < sx->max_rcpt; /*XXX maybe also || sx->single_rcpt_domain ? */
3253 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3256 if (!(addr->dsn_flags & rf_dsnlasthop))
3258 sx->dsn_all_lasthop = FALSE;
3263 /* Add any DSN flags to the mail command */
3265 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3267 if (dsn_ret == dsn_ret_hdrs)
3268 { Ustrcpy(p, US" RET=HDRS"); p += 9; }
3269 else if (dsn_ret == dsn_ret_full)
3270 { Ustrcpy(p, US" RET=FULL"); p += 9; }
3274 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3279 /* If an authenticated_sender override has been specified for this transport
3280 instance, expand it. If the expansion is forced to fail, and there was already
3281 an authenticated_sender for this message, the original value will be used.
3282 Other expansion failures are serious. An empty result is ignored, but there is
3283 otherwise no check - this feature is expected to be used with LMTP and other
3284 cases where non-standard addresses (e.g. without domains) might be required. */
3286 return smtp_mail_auth_str(sx, p, addrlist) ? ERROR : OK;
3291 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3293 uschar * p = sx->buffer;
3296 /* Add any DSN flags to the rcpt command */
3298 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3300 if (addr->dsn_flags & rf_dsnflags)
3304 Ustrcpy(p, US" NOTIFY=");
3306 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3308 if (!first) *p++ = ',';
3310 Ustrcpy(p, rf_names[i]);
3315 if (addr->dsn_orcpt)
3317 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3328 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3329 -1 MAIL response error
3330 -2 any non-MAIL read i/o error
3331 -3 non-MAIL response timeout
3332 -4 internal error; channel still usable
3337 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3339 address_item * addr;
3340 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3341 address_item * restart_addr = NULL;
3343 int address_count, pipe_limit;
3346 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3352 /* From here until we send the DATA command, we can make use of PIPELINING
3353 if the server host supports it. The code has to be able to check the responses
3354 at any point, for when the buffer fills up, so we write it totally generally.
3355 When PIPELINING is off, each command written reports that it has flushed the
3358 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3361 uschar * s = sx->from_addr;
3363 uschar * errstr = NULL;
3365 /* If we must downconvert, do the from-address here. Remember we had to
3366 for the to-addresses (done below), and also (ugly) for re-doing when building
3367 the delivery log line. */
3369 if ( sx->addrlist->prop.utf8_msg
3370 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3373 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3375 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, &sx->delivery_start);
3379 setflag(sx->addrlist, af_utf8_downcvt);
3383 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3384 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3387 mail_command = string_copy(big_buffer); /* Save for later error message */
3391 case -1: /* Transmission error */
3394 case +1: /* Cmd was sent */
3395 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3396 (SOB sx->conn_args.ob)->command_timeout))
3398 if (errno == 0 && sx->buffer[0] == '4')
3400 errno = ERRNO_MAIL4XX;
3401 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3405 sx->pending_MAIL = FALSE;
3408 /* otherwise zero: command queued for pipeline */
3411 /* Pass over all the relevant recipient addresses for this host, which are the
3412 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3413 several before we have to read the responses for those seen so far. This
3414 checking is done by a subroutine because it also needs to be done at the end.
3415 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3416 the next one if not all are sent.
3418 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3419 last address because we want to abort if any recipients have any kind of
3420 problem, temporary or permanent. We know that all recipient addresses will have
3421 the PENDING_DEFER status, because only one attempt is ever made, and we know
3422 that max_rcpt will be large, so all addresses will be done at once.
3424 For verify we flush the pipeline after any (the only) rcpt address. */
3426 for (addr = sx->first_addr, address_count = 0, pipe_limit = 100;
3427 addr && address_count < sx->max_rcpt;
3428 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3434 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3435 if ( sx->single_rcpt_domain /* restriction on domains */
3436 && address_count > 0 /* not first being sent */
3437 && Ustrcmp(addr->domain, sx->first_addr->domain) != 0 /* dom diff from first */
3440 DEBUG(D_transport) debug_printf("skipping different domain %s\n", addr->domain);
3442 /* Ensure the smtp-response reaper does not think the address had a RCPT
3443 command sent for it. Reset to PENDING_DEFER in smtp_deliver(), where we
3444 goto SEND_MESSAGE. */
3446 addr->transport_return = SKIP;
3447 if (!restart_addr) restart_addr = addr; /* note restart point */
3448 continue; /* skip this one */
3452 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3453 ? dsn_support_yes : dsn_support_no;
3456 if (pipe_limit-- <= 0)
3457 { no_flush = FALSE; pipe_limit = 100; }
3459 no_flush = pipelining_active && !sx->verify
3460 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3462 build_rcptcmd_options(sx, addr);
3464 /* Now send the RCPT command, and process outstanding responses when
3465 necessary. After a timeout on RCPT, we just end the function, leaving the
3466 yield as OK, because this error can often mean that there is a problem with
3467 just one address, so we don't want to delay the host. */
3469 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3472 if ( testflag(sx->addrlist, af_utf8_downcvt)
3473 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3476 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3477 errno = ERRNO_EXPANDFAIL;
3478 return -5; /*XXX too harsh? */
3482 cmds_sent = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3483 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3485 if (cmds_sent < 0) return -5;
3488 switch(sync_responses(sx, cmds_sent, 0))
3490 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3491 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3494 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3495 if (!sx->lmtp) /* can't tell about progress yet */
3496 sx->completed_addr = TRUE;
3497 case 0: /* No 2xx or 5xx, but no probs */
3498 /* If any RCPT got a 452 response then next_addr has been updated
3499 for restarting with a new MAIL on the same connection. Send no more
3500 RCPTs for this MAIL. */
3504 DEBUG(D_transport) debug_printf("seen 452 too-many-rcpts\n");
3505 sx->RCPT_452 = FALSE;
3506 /* sx->next_addr has been reset for fast_retry */
3511 case -1: return -3; /* Timeout on RCPT */
3512 case -2: return -2; /* non-MAIL read i/o error */
3513 default: return -1; /* any MAIL error */
3515 #ifndef DISABLE_PIPE_CONNECT
3516 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3517 case -5: return -1; /* TLS first-read error */
3521 } /* Loop for next address */
3523 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3524 sx->next_addr = restart_addr ? restart_addr : addr;
3526 sx->next_addr = addr;
3533 /*****************************************************
3534 * Proxy TLS connection for another transport process *
3535 ******************************************************/
3537 Close the unused end of the pipe, fork once more, then use the given buffer
3538 as a staging area, and select on both the given fd and the TLS'd client-fd for
3539 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3540 Do blocking full-size writes, and reads under a timeout. Once both input
3541 channels are closed, exit the process.
3545 buf space to use for buffering
3546 bufsiz size of buffer
3547 pfd pipe filedescriptor array; [0] is comms to proxied process
3548 timeout per-read timeout, seconds
3549 host hostname of remote
3555 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3556 int timeout, const uschar * host)
3558 struct pollfd p[2] = {{.fd = tls_out.active.sock, .events = POLLIN},
3559 {.fd = pfd[0], .events = POLLIN}};
3561 BOOL send_tls_shutdown = TRUE;
3564 if ((rc = exim_fork(US"tls-proxy")))
3565 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3567 set_process_info("proxying TLS connection for continued transport to %s\n", host);
3571 time_t time_left = timeout;
3572 time_t time_start = time(NULL);
3577 rc = poll(p, 2, time_left * 1000);
3579 if (rc < 0 && errno == EINTR)
3580 if ((time_left -= time(NULL) - time_start) > 0) continue;
3584 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3588 /* For errors where not readable, bomb out */
3590 if (p[0].revents & POLLERR || p[1].revents & POLLERR)
3592 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3593 p[0].revents & POLLERR ? "tls" : "proxy");
3594 if (!(p[0].revents & POLLIN || p[1].events & POLLIN))
3596 DEBUG(D_transport) debug_printf("- but also readable; no exit yet\n");
3599 while (rc < 0 || !(p[0].revents & POLLIN || p[1].revents & POLLIN));
3601 /* handle inbound data */
3602 if (p[0].revents & POLLIN)
3603 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0) /* Expect -1 for EOF; */
3604 { /* that reaps the TLS Close Notify record */
3606 shutdown(pfd[0], SHUT_WR);
3610 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3611 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3613 /* Handle outbound data. We cannot combine payload and the TLS-close
3614 due to the limitations of the (pipe) channel feeding us. Maybe use a unix-domain
3616 if (p[1].revents & POLLIN)
3617 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3621 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
3622 (void) setsockopt(tls_out.active.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
3624 tls_shutdown_wr(ct_ctx);
3625 send_tls_shutdown = FALSE;
3626 shutdown(tls_out.active.sock, SHUT_WR);
3629 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3630 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3633 while (p[0].fd >= 0 || p[1].fd >= 0);
3636 if (send_tls_shutdown) tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3638 testharness_pause_ms(100); /* let logging complete */
3639 exim_exit(EXIT_SUCCESS);
3644 /*************************************************
3645 * Deliver address list to given host *
3646 *************************************************/
3648 /* If continue_hostname is not null, we get here only when continuing to
3649 deliver down an existing channel. The channel was passed as the standard
3650 input. TLS is never active on a passed channel; the previous process either
3651 closes it down before passing the connection on, or inserts a TLS-proxy
3652 process and passes on a cleartext conection.
3654 Otherwise, we have to make a connection to the remote host, and do the
3655 initial protocol exchange.
3657 When running as an MUA wrapper, if the sender or any recipient is rejected,
3658 temporarily or permanently, we force failure for all recipients.
3661 addrlist chain of potential addresses to deliver; only those whose
3662 transport_return field is set to PENDING_DEFER are currently
3663 being processed; others should be skipped - they have either
3664 been delivered to an earlier host or IP address, or been
3665 failed by one of them.
3666 host host to deliver to
3667 host_af AF_INET or AF_INET6
3668 defport default TCP/IP port to use if host does not specify, in host
3670 interface interface to bind to, or NULL
3671 tblock transport instance block
3672 message_defer set TRUE if yield is OK, but all addresses were deferred
3673 because of a non-recipient, non-host failure, that is, a
3674 4xx response to MAIL FROM, DATA, or ".". This is a defer
3675 that is specific to the message.
3676 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3677 a second attempt after TLS initialization fails
3679 Returns: OK - the connection was made and the delivery attempted;
3680 the result for each address is in its data block.
3681 DEFER - the connection could not be made, or something failed
3682 while setting up the SMTP session, or there was a
3683 non-message-specific error, such as a timeout.
3684 ERROR - a filter command is specified for this transport,
3685 and there was a problem setting it up; OR helo_data
3686 or add_headers or authenticated_sender is specified
3687 for this transport, and the string failed to expand
3689 For all non-OK returns the first addr of the list carries the
3690 time taken for the attempt.
3694 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3695 uschar *interface, transport_instance *tblock,
3696 BOOL *message_defer, BOOL suppress_tls)
3698 smtp_transport_options_block * ob = SOB tblock->options_block;
3703 uschar *message = NULL;
3704 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3705 smtp_context * sx = store_get(sizeof(*sx), GET_TAINTED); /* tainted, for the data buffers */
3706 BOOL pass_message = FALSE;
3707 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3708 BOOL mail_limit = FALSE;
3713 BOOL tcw_done = FALSE, tcw = FALSE;
3715 *message_defer = FALSE;
3717 memset(sx, 0, sizeof(*sx));
3718 sx->addrlist = addrlist;
3719 sx->conn_args.host = host;
3720 sx->conn_args.host_af = host_af;
3722 sx->conn_args.interface = interface;
3723 sx->helo_data = NULL;
3724 sx->conn_args.tblock = tblock;
3725 sx->conn_args.sock = -1;
3726 gettimeofday(&sx->delivery_start, NULL);
3727 sx->sync_addr = sx->first_addr = addrlist;
3734 /* Get the channel set up ready for a message, MAIL FROM being the next
3735 SMTP command to send. */
3737 if ((rc = smtp_setup_conn(sx, suppress_tls)) != OK)
3739 timesince(&addrlist->delivery_time, &sx->delivery_start);
3745 /* If the connection used DANE, ignore for now any addresses with incompatible
3746 domains. The SNI has to be the domain. Arrange a whole new TCP conn later,
3747 just in case only TLS isn't enough. */
3749 if (sx->conn_args.dane)
3751 const uschar * dane_domain = sx->first_addr->domain;
3753 for (address_item * a = sx->first_addr->next; a; a = a->next)
3754 if ( a->transport_return == PENDING_DEFER
3755 && Ustrcmp(dane_domain, a->domain) != 0)
3757 DEBUG(D_transport) debug_printf("DANE: holding %s for later\n", a->domain);
3759 a->transport_return = DANE;
3764 /* If there is a filter command specified for this transport, we can now
3765 set it up. This cannot be done until the identity of the host is known. */
3767 if (tblock->filter_command)
3769 transport_filter_timeout = tblock->filter_timeout;
3771 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3774 if (!transport_set_up_command(&transport_filter_argv,
3775 tblock->filter_command, TRUE, DEFER, addrlist, FALSE,
3776 string_sprintf("%.50s transport filter", tblock->name), NULL))
3778 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3779 FALSE, &sx->delivery_start);
3784 if ( transport_filter_argv
3785 && *transport_filter_argv
3786 && **transport_filter_argv
3787 && smtp_peer_options & OPTION_CHUNKING
3788 #ifndef DISABLE_DKIM
3789 /* When dkim signing, chunking is handled even with a transport-filter */
3790 && !(ob->dkim.dkim_private_key && ob->dkim.dkim_domain && ob->dkim.dkim_selector)
3791 && !ob->dkim.force_bodyhash
3795 smtp_peer_options &= ~OPTION_CHUNKING;
3796 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3800 /* For messages that have more than the maximum number of envelope recipients,
3801 we want to send several transactions down the same SMTP connection. (See
3802 comments in deliver.c as to how this reconciles, heuristically, with
3803 remote_max_parallel.) This optimization was added to Exim after the following
3804 code was already working. The simplest way to put it in without disturbing the
3805 code was to use a goto to jump back to this point when there is another
3806 transaction to handle. */
3809 sx->from_addr = return_path;
3810 sx->sync_addr = sx->first_addr;
3812 sx->send_rset = TRUE;
3813 sx->completed_addr = FALSE;
3816 /* If we are a continued-connection-after-verify the MAIL and RCPT
3817 commands were already sent; do not re-send but do mark the addrs as
3818 having been accepted up to RCPT stage. A traditional cont-conn
3819 always has a sequence number greater than one. */
3821 if (continue_hostname && continue_sequence == 1)
3823 /* sx->pending_MAIL = FALSE; */
3825 /* sx->next_addr = NULL; */
3827 for (address_item * addr = addrlist; addr; addr = addr->next)
3828 addr->transport_return = PENDING_OK;
3832 /* Initiate a message transfer. */
3834 switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))
3837 case -1: case -2: goto RESPONSE_FAILED;
3838 case -3: goto END_OFF;
3839 case -4: goto SEND_QUIT;
3840 default: goto SEND_FAILED;
3843 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3844 permanently or temporarily. We should have flushed and synced after the last
3852 for (a = sx->first_addr, cnt = 0; a && cnt < sx->max_rcpt; a = a->next, cnt++)
3853 if (a->transport_return != PENDING_OK)
3855 /*XXX could we find a better errno than 0 here? */
3856 set_errno_nohost(addrlist, 0, a->message, FAIL,
3857 testflag(a, af_pass_message), &sx->delivery_start);
3864 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3865 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3866 have a good recipient buffered up if we are pipelining. We don't want to waste
3867 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3868 are pipelining. The responses are all handled by sync_responses().
3869 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3872 if ( !(smtp_peer_options & OPTION_CHUNKING)
3873 && (sx->ok || (pipelining_active && !mua_wrapper)))
3875 int count = smtp_write_command(sx, SCMD_FLUSH, "DATA\r\n");
3877 if (count < 0) goto SEND_FAILED;
3878 switch(sync_responses(sx, count, sx->ok ? +1 : -1))
3880 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3881 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3884 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3885 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
3886 case 0: break; /* No 2xx or 5xx, but no probs */
3888 case -1: goto END_OFF; /* Timeout on RCPT */
3890 #ifndef DISABLE_PIPE_CONNECT
3891 case -5: /* TLS first-read error */
3892 case -4: HDEBUG(D_transport)
3893 debug_printf("failed reaping pipelined cmd responses\n");
3895 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3897 pipelining_active = FALSE;
3898 data_command = string_copy(big_buffer); /* Save for later error message */
3901 /* If there were no good recipients (but otherwise there have been no
3902 problems), just set ok TRUE, since we have handled address-specific errors
3903 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3904 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3905 well as body. Set the appropriate timeout value to be used for each chunk.
3906 (Haven't been able to make it work using select() for writing yet.) */
3909 && (!(smtp_peer_options & OPTION_CHUNKING) || !pipelining_active))
3911 /* Save the first address of the next batch. */
3912 sx->first_addr = sx->next_addr;
3918 transport_ctx tctx = {
3919 .u = {.fd = sx->cctx.sock}, /*XXX will this need TLS info? */
3922 .check_string = US".",
3923 .escape_string = US"..", /* Escaping strings */
3925 topt_use_crlf | topt_escape_headers
3926 | (tblock->body_only ? topt_no_headers : 0)
3927 | (tblock->headers_only ? topt_no_body : 0)
3928 | (tblock->return_path_add ? topt_add_return_path : 0)
3929 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3930 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3933 /* If using CHUNKING we need a callback from the generic transport
3934 support to us, for the sending of BDAT smtp commands and the reaping
3935 of responses. The callback needs a whole bunch of state so set up
3936 a transport-context structure to be passed around. */
3938 if (smtp_peer_options & OPTION_CHUNKING)
3940 tctx.check_string = tctx.escape_string = NULL;
3941 tctx.options |= topt_use_bdat;
3942 tctx.chunk_cb = smtp_chunk_cmd_callback;
3943 sx->pending_BDAT = FALSE;
3944 sx->good_RCPT = sx->ok;
3946 tctx.smtp_context = sx;
3949 tctx.options |= topt_end_dot;
3951 /* Save the first address of the next batch. */
3952 sx->first_addr = sx->next_addr;
3954 /* Responses from CHUNKING commands go in buffer. Otherwise,
3955 there has not been a response. */
3959 sigalrm_seen = FALSE;
3960 transport_write_timeout = ob->data_timeout;
3961 smtp_command = US"sending data block"; /* For error messages */
3962 DEBUG(D_transport|D_v)
3963 if (smtp_peer_options & OPTION_CHUNKING)
3964 debug_printf(" will write message using CHUNKING\n");
3966 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3967 transport_count = 0;
3969 #ifndef DISABLE_DKIM
3971 # ifdef MEASURE_TIMING
3973 gettimeofday(&t0, NULL);
3975 dkim_exim_sign_init();
3976 # ifdef EXPERIMENTAL_ARC
3978 uschar * s = ob->arc_sign;
3981 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
3983 if (!f.expand_string_forcedfail)
3985 message = US"failed to expand arc_sign";
3992 /* Ask dkim code to hash the body for ARC */
3993 (void) arc_ams_setup_sign_bodyhash();
3994 ob->dkim.force_bodyhash = TRUE;
3999 # ifdef MEASURE_TIMING
4000 report_time_since(&t0, US"dkim_exim_sign_init (delta)");
4005 /* See if we can pipeline QUIT. Reasons not to are
4006 - pipelining not active
4007 - not ok to send quit
4008 - errors in amtp transation responses
4009 - more addrs to send for this message or this host
4010 - this message was being retried
4011 - more messages for this host
4012 If we can, we want the message-write to not flush (the tail end of) its data out. */
4014 if ( sx->pipelining_used
4015 && (sx->ok && sx->completed_addr || smtp_peer_options & OPTION_CHUNKING)
4017 && !(sx->first_addr || f.continue_more)
4018 && f.deliver_firsttime
4021 smtp_compare_t t_compare =
4022 {.tblock = tblock, .current_sender_address = sender_address};
4027 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4028 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4032 transport_check_waiting(tblock->name, host->name,
4033 tblock->connection_max_messages, new_message_id,
4034 (oicf)smtp_are_same_identities, (void*)&t_compare);
4037 HDEBUG(D_transport) debug_printf("will pipeline QUIT\n");
4038 tctx.options |= topt_no_flush;
4042 #ifndef DISABLE_DKIM
4043 sx->ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
4045 sx->ok = transport_write_message(&tctx, 0);
4048 /* transport_write_message() uses write() because it is called from other
4049 places to write to non-sockets. This means that under some OS (e.g. Solaris)
4050 it can exit with "Broken pipe" as its error. This really means that the
4051 socket got closed at the far end. */
4053 transport_write_timeout = 0; /* for subsequent transports */
4055 /* Failure can either be some kind of I/O disaster (including timeout),
4056 or the failure of a transport filter or the expansion of added headers.
4057 Or, when CHUNKING, it can be a protocol-detected failure. */
4060 if (message) goto SEND_FAILED;
4061 else goto RESPONSE_FAILED;
4063 /* We used to send the terminating "." explicitly here, but because of
4064 buffering effects at both ends of TCP/IP connections, you don't gain
4065 anything by keeping it separate, so it might as well go in the final
4066 data buffer for efficiency. This is now done by setting the topt_end_dot
4069 smtp_command = US"end of data";
4071 /* If we can pipeline a QUIT with the data them send it now. If a new message
4072 for this host appeared in the queue while data was being sent, we will not see
4073 it and it will have to wait for a queue run. If there was one but another
4074 thread took it, we might attempt to send it - but locking of spoolfiles will
4075 detect that. Use _MORE to get QUIT in FIN segment. */
4077 if (tcw_done && !tcw)
4079 /*XXX jgh 2021/03/10 google et. al screwup. G, at least, sends TCP FIN in response to TLS
4080 close-notify. Under TLS 1.3, violating RFC.
4081 However, TLS 1.2 does not have half-close semantics. */
4083 if ( sx->cctx.tls_ctx
4084 #if 0 && !defined(DISABLE_TLS)
4085 && Ustrcmp(tls_out.ver, "TLS1.3") != 0
4087 || !f.deliver_firsttime
4089 { /* Send QUIT now and not later */
4090 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
4091 sx->send_quit = FALSE;
4094 { /* add QUIT to the output buffer */
4095 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4096 sx->send_quit = FALSE; /* avoid sending it later */
4099 if (sx->cctx.tls_ctx && sx->send_tlsclose) /* need to send TLS Close Notify */
4101 # ifdef EXIM_TCP_CORK /* Use _CORK to get Close Notify in FIN segment */
4102 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4104 tls_shutdown_wr(sx->cctx.tls_ctx);
4105 sx->send_tlsclose = FALSE; /* avoid later repeat */
4108 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4109 shutdown(sx->cctx.sock, SHUT_WR); /* flush output buffer, with TCP FIN */
4113 if (smtp_peer_options & OPTION_CHUNKING && sx->cmd_count > 1)
4115 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
4116 switch(sync_responses(sx, sx->cmd_count-1, 0))
4118 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
4119 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
4122 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
4123 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
4124 case 0: break; /* No 2xx or 5xx, but no probs */
4126 case -1: goto END_OFF; /* Timeout on RCPT */
4128 #ifndef DISABLE_PIPE_CONNECT
4129 case -5: /* TLS first-read error */
4130 case -4: HDEBUG(D_transport)
4131 debug_printf("failed reaping pipelined cmd responses\n");
4133 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
4137 #ifndef DISABLE_PRDR
4138 /* For PRDR we optionally get a partial-responses warning followed by the
4139 individual responses, before going on with the overall response. If we don't
4140 get the warning then deal with per non-PRDR. */
4144 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '3', ob->final_timeout);
4145 if (!sx->ok && errno == 0) switch(sx->buffer[0])
4147 case '2': sx->prdr_active = FALSE;
4150 case '4': errno = ERRNO_DATA4XX;
4151 addrlist->more_errno |=
4152 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4159 /* For non-PRDR SMTP, we now read a single response that applies to the
4160 whole message. If it is OK, then all the addresses have been delivered. */
4164 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4166 if (!sx->ok && errno == 0 && sx->buffer[0] == '4')
4168 errno = ERRNO_DATA4XX;
4169 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4173 /* For LMTP, we get back a response for every RCPT command that we sent;
4174 some may be accepted and some rejected. For those that get a response, their
4175 status is fixed; any that are accepted have been handed over, even if later
4176 responses crash - at least, that's how I read RFC 2033.
4178 If all went well, mark the recipient addresses as completed, record which
4179 host/IPaddress they were delivered to, and cut out RSET when sending another
4180 message down the same channel. Write the completed addresses to the journal
4181 now so that they are recorded in case there is a crash of hardware or
4182 software before the spool gets updated. Also record the final SMTP
4183 confirmation if needed (for SMTP only). */
4188 struct timeval delivery_time;
4190 uschar * conf = NULL;
4192 timesince(&delivery_time, &sx->delivery_start);
4193 sx->send_rset = FALSE;
4194 pipelining_active = FALSE;
4196 /* Set up confirmation if needed - applies only to SMTP */
4199 #ifdef DISABLE_EVENT
4200 LOGGING(smtp_confirmation) &&
4205 const uschar * s = string_printing(sx->buffer);
4206 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4207 conf = s == sx->buffer ? US string_copy(s) : US s;
4210 /* Process all transported addresses - for LMTP or PRDR, read a status for
4211 each one. We used to drop out at first_addr, until someone returned a 452
4212 followed by a 250... and we screwed up the accepted addresses. */
4214 for (address_item * addr = addrlist; addr; addr = addr->next)
4216 if (addr->transport_return != PENDING_OK) continue;
4218 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
4219 remaining addresses. Otherwise, it's a return code for just the one
4220 address. For temporary errors, add a retry item for the address so that
4221 it doesn't get tried again too soon. */
4223 #ifndef DISABLE_PRDR
4224 if (sx->lmtp || sx->prdr_active)
4229 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4232 if (errno != 0 || sx->buffer[0] == 0) goto RESPONSE_FAILED;
4233 addr->message = string_sprintf(
4234 #ifndef DISABLE_PRDR
4235 "%s error after %s: %s", sx->prdr_active ? "PRDR":"LMTP",
4237 "LMTP error after %s: %s",
4239 data_command, string_printing(sx->buffer));
4240 setflag(addr, af_pass_message); /* Allow message to go to user */
4241 if (sx->buffer[0] == '5')
4242 addr->transport_return = FAIL;
4245 errno = ERRNO_DATA4XX;
4246 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4247 addr->transport_return = DEFER;
4248 #ifndef DISABLE_PRDR
4249 if (!sx->prdr_active)
4251 retry_add_item(addr, addr->address_retry_key, 0);
4255 sx->completed_addr = TRUE; /* NOW we can set this flag */
4256 if (LOGGING(smtp_confirmation))
4258 const uschar *s = string_printing(sx->buffer);
4259 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4260 conf = (s == sx->buffer) ? US string_copy(s) : US s;
4264 /* SMTP, or success return from LMTP for this address. Pass back the
4265 actual host that was used. */
4267 addr->transport_return = OK;
4268 addr->host_used = host;
4269 addr->delivery_time = delivery_time;
4270 addr->special_action = flag;
4271 addr->message = conf;
4273 if (tcp_out_fastopen)
4275 setflag(addr, af_tcp_fastopen_conn);
4276 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
4277 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
4279 if (sx->pipelining_used) setflag(addr, af_pipelining);
4280 #ifndef DISABLE_PIPE_CONNECT
4281 if (sx->early_pipe_active) setflag(addr, af_early_pipe);
4283 #ifndef DISABLE_PRDR
4284 if (sx->prdr_active) setflag(addr, af_prdr_used);
4286 if (smtp_peer_options & OPTION_CHUNKING) setflag(addr, af_chunking_used);
4289 #ifndef DISABLE_PRDR
4290 if (!sx->prdr_active)
4293 /* Update the journal. For homonymic addresses, use the base address plus
4294 the transport name. See lots of comments in deliver.c about the reasons
4295 for the complications when homonyms are involved. Just carry on after
4296 write error, as it may prove possible to update the spool file later. */
4298 if (testflag(addr, af_homonym))
4299 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4301 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4303 DEBUG(D_deliver) debug_printf("S:journalling %s", sx->buffer);
4304 len = Ustrlen(CS sx->buffer);
4305 if (write(journal_fd, sx->buffer, len) != len)
4306 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4307 "%s: %s", sx->buffer, strerror(errno));
4311 #ifndef DISABLE_PRDR
4312 if (sx->prdr_active)
4314 const uschar * overall_message;
4316 /* PRDR - get the final, overall response. For any non-success
4317 upgrade all the address statuses. */
4319 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4323 if(errno == 0 && sx->buffer[0] == '4')
4325 errno = ERRNO_DATA4XX;
4326 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4328 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4329 if (sx->buffer[0] == '5' || addr->transport_return == OK)
4330 addr->transport_return = PENDING_OK; /* allow set_errno action */
4331 goto RESPONSE_FAILED;
4334 /* Append the overall response to the individual PRDR response for logging
4335 and update the journal, or setup retry. */
4337 overall_message = string_printing(sx->buffer);
4338 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4339 if (addr->transport_return == OK)
4340 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
4342 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4343 if (addr->transport_return == OK)
4345 if (testflag(addr, af_homonym))
4346 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4348 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4350 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx->buffer);
4351 len = Ustrlen(CS sx->buffer);
4352 if (write(journal_fd, sx->buffer, len) != len)
4353 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4354 "%s: %s", sx->buffer, strerror(errno));
4356 else if (addr->transport_return == DEFER)
4357 /*XXX magic value -2 ? maybe host+message ? */
4358 retry_add_item(addr, addr->address_retry_key, -2);
4362 /* Ensure the journal file is pushed out to disk. */
4364 if (EXIMfsync(journal_fd) < 0)
4365 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
4371 /* Handle general (not specific to one address) failures here. The value of ok
4372 is used to skip over this code on the falling through case. A timeout causes a
4373 deferral. Other errors may defer or fail according to the response code, and
4374 may set up a special errno value, e.g. after connection chopped, which is
4375 assumed if errno == 0 and there is no text in the buffer. If control reaches
4376 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
4377 the problem is not related to this specific message. */
4382 uschar * set_message;
4388 /* Clear send_quit flag if needed. Do not set. */
4389 sx->send_quit &= check_response(host, &save_errno, addrlist->more_errno,
4390 sx->buffer, &code, &message, &pass_message);
4398 message = string_sprintf("smtp send to %s [%s] failed: %s",
4399 host->name, host->address, message ? message : US strerror(save_errno));
4400 sx->send_quit = FALSE;
4408 sx->ok = FALSE; /* For when reached by GOTO */
4409 set_message = message;
4411 /* We want to handle timeouts after MAIL or "." and loss of connection after
4412 "." specially. They can indicate a problem with the sender address or with
4413 the contents of the message rather than a real error on the connection. These
4414 cases are treated in the same way as a 4xx response. This next bit of code
4415 does the classification. */
4422 message_error = TRUE;
4426 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4427 Ustrncmp(smtp_command,"end ",4) == 0;
4430 case ERRNO_SMTPCLOSED:
4431 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4434 #ifndef DISABLE_DKIM
4436 /* DKIM signing failure: avoid thinking we pipelined quit,
4437 just abandon the message and close the socket. */
4439 message_error = FALSE;
4440 # ifndef DISABLE_TLS
4441 if (sx->cctx.tls_ctx)
4443 tls_close(sx->cctx.tls_ctx,
4444 sx->send_tlsclose ? TLS_SHUTDOWN_WAIT : TLS_SHUTDOWN_WONLY);
4445 sx->cctx.tls_ctx = NULL;
4451 message_error = FALSE;
4455 /* Handle the cases that are treated as message errors. These are:
4457 (a) negative response or timeout after MAIL
4458 (b) negative response after DATA
4459 (c) negative response or timeout or dropped connection after "."
4460 (d) utf8 support required and not offered
4462 It won't be a negative response or timeout after RCPT, as that is dealt
4463 with separately above. The action in all cases is to set an appropriate
4464 error code for all the addresses, but to leave yield set to OK because the
4465 host itself has not failed. Of course, it might in practice have failed
4466 when we've had a timeout, but if so, we'll discover that at the next
4467 delivery attempt. For a temporary error, set the message_defer flag, and
4468 write to the logs for information if this is not the last host. The error
4469 for the last host will be logged as part of the address's log line. */
4473 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4475 /* If there's an errno, the message contains just the identity of
4480 else /* Anything other than 5 is treated as temporary */
4484 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4486 write_logs(host, message, sx->first_addr ? sx->first_addr->basic_errno : 0);
4488 *message_defer = TRUE;
4491 DEBUG(D_transport) if (sx->cctx.sock >= 0)
4494 if (ioctl(sx->cctx.sock, TIOCOUTQ, &n) == 0)
4495 debug_printf("%d bytes remain in socket output buffer\n", n);
4499 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4500 ".", or some other transportation error. We defer all addresses and yield
4501 DEFER, except for the case of failed add_headers expansion, or a transport
4502 filter failure, when the yield should be ERROR, to stop it trying other
4507 #ifndef DISABLE_PIPE_CONNECT
4508 /* If we were early-pipelinng and the actual EHLO response did not match
4509 the cached value we assumed, we could have detected it and passed a
4510 custom errno through to here. It would be nice to RSET and retry right
4511 away, but to reliably do that we eould need an extra synch point before
4512 we committed to data and that would discard half the gained roundrips.
4513 Or we could summarily drop the TCP connection. but that is also ugly.
4514 Instead, we ignore the possibility (having freshened the cache) and rely
4515 on the server telling us with a nonmessage error if we have tried to
4516 do something it no longer supports. */
4519 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4520 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4524 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host,
4525 #ifdef EXPERIMENTAL_DSN_INFO
4526 sx->smtp_greeting, sx->helo_response,
4528 &sx->delivery_start);
4531 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4532 SMTP session tidily. However, if there were too many addresses to send in one
4533 message (indicated by first_addr being non-NULL) we want to carry on with the
4534 rest of them. Also, it is desirable to send more than one message down the SMTP
4535 connection if there are several waiting, provided we haven't already sent so
4536 many as to hit the configured limit. The function transport_check_waiting looks
4537 for a waiting message and returns its id. Then transport_pass_socket tries to
4538 set up a continued delivery by passing the socket on to another process. The
4539 variable send_rset is FALSE if a message has just been successfully transferred.
4541 If we are already sending down a continued channel, there may be further
4542 addresses not yet delivered that are aimed at the same host, but which have not
4543 been passed in this run of the transport. In this case, continue_more will be
4544 true, and all we should do is send RSET if necessary, and return, leaving the
4547 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4548 do not want to continue with other messages down the same channel, because that
4549 can lead to looping between two or more messages, all with the same,
4550 temporarily failing address(es). [The retry information isn't updated yet, so
4551 new processes keep on trying.] We probably also don't want to try more of this
4552 message's addresses either.
4554 If we have started a TLS session, we have to end it before passing the
4555 connection to a new process. However, not all servers can handle this (Exim
4556 can), so we do not pass such a connection on if the host matches
4557 hosts_nopass_tls. */
4560 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4561 "yield=%d first_address is %sNULL\n", sx->ok, sx->send_quit,
4562 sx->send_rset, f.continue_more, yield, sx->first_addr ? "not " : "");
4564 if (sx->completed_addr && sx->ok && sx->send_quit)
4565 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4566 if (mail_limit = continue_sequence >= sx->max_mail)
4569 debug_printf("reached limit %u for MAILs per conn\n", sx->max_mail);
4574 smtp_compare_t t_compare =
4575 {.tblock = tblock, .current_sender_address = sender_address};
4577 if ( sx->first_addr /* more addrs for this message */
4578 || f.continue_more /* more addrs for continued-host */
4579 || tcw_done && tcw /* more messages for host */
4582 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4583 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4587 transport_check_waiting(tblock->name, host->name,
4588 sx->max_mail, new_message_id,
4589 (oicf)smtp_are_same_identities, (void*)&t_compare)
4596 if (! (sx->ok = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4598 msg = US string_sprintf("smtp send to %s [%s] failed: %s", host->name,
4599 host->address, strerror(errno));
4600 sx->send_quit = FALSE;
4602 else if (! (sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4603 '2', ob->command_timeout)))
4606 sx->send_quit = check_response(host, &errno, 0, sx->buffer, &code, &msg,
4610 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4611 host->name, host->address, msg);
4615 /* Either RSET was not needed, or it succeeded */
4622 int socket_fd = sx->cctx.sock;
4624 if (sx->first_addr) /* More addresses still to be sent */
4625 { /* for this message */
4626 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4627 /* Any that we marked as skipped, reset to do now */
4628 for (address_item * a = sx->first_addr; a; a = a->next)
4629 if (a->transport_return == SKIP)
4630 a->transport_return = PENDING_DEFER;
4632 continue_sequence++; /* for consistency */
4633 clearflag(sx->first_addr, af_new_conn);
4634 setflag(sx->first_addr, af_cont_conn); /* Causes * in logging */
4635 pipelining_active = sx->pipelining_used; /* was cleared at DATA */
4639 /* Unless caller said it already has more messages listed for this host,
4640 pass the connection on to a new Exim process (below, the call to
4641 transport_pass_socket). If the caller has more ready, just return with
4642 the connection still open. */
4645 if (tls_out.active.sock >= 0)
4646 if ( f.continue_more
4647 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4649 /* Before passing the socket on, or returning to caller with it still
4650 open, we must shut down TLS. Not all MTAs allow for the continuation
4651 of the SMTP session when TLS is shut down. We test for this by sending
4652 a new EHLO. If we don't get a good response, we don't attempt to pass
4655 tls_close(sx->cctx.tls_ctx,
4656 sx->send_tlsclose ? TLS_SHUTDOWN_WAIT : TLS_SHUTDOWN_WONLY);
4657 sx->send_tlsclose = FALSE;
4658 sx->cctx.tls_ctx = NULL;
4659 tls_out.active.sock = -1;
4660 smtp_peer_options = smtp_peer_options_wrap;
4662 && smtp_write_command(sx, SCMD_FLUSH, "EHLO %s\r\n", sx->helo_data)
4664 && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4665 '2', ob->command_timeout);
4667 if (sx->ok && f.continue_more)
4668 goto TIDYUP; /* More addresses for another run */
4672 /* Set up a pipe for proxying TLS for the new transport process */
4674 smtp_peer_options |= OPTION_TLS;
4675 if ((sx->ok = socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4678 set_errno(sx->first_addr, errno, US"internal allocation problem",
4680 # ifdef EXPERIMENTAL_DSN_INFO
4681 sx->smtp_greeting, sx->helo_response,
4683 &sx->delivery_start);
4687 if (f.continue_more)
4688 goto TIDYUP; /* More addresses for another run */
4690 /* If the socket is successfully passed, we mustn't send QUIT (or
4691 indeed anything!) from here. */
4693 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4694 propagate it from the initial
4696 if (sx->ok && transport_pass_socket(tblock->name, host->name,
4697 host->address, new_message_id, socket_fd
4698 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4699 , sx->peer_limit_mail, sx->peer_limit_rcpt, sx->peer_limit_rcptdom
4703 sx->send_quit = FALSE;
4705 /* We have passed the client socket to a fresh transport process.
4706 If TLS is still active, we need to proxy it for the transport we
4707 just passed the baton to. Fork a child to to do it, and return to
4708 get logging done asap. Which way to place the work makes assumptions
4709 about post-fork prioritisation which may not hold on all platforms. */
4711 if (tls_out.active.sock >= 0)
4713 int pid = exim_fork(US"tls-proxy-interproc");
4714 if (pid == 0) /* child; fork again to disconnect totally */
4716 /* does not return */
4717 smtp_proxy_tls(sx->cctx.tls_ctx, sx->buffer, sizeof(sx->buffer), pfd,
4718 ob->command_timeout, host->name);
4721 if (pid > 0) /* parent */
4724 /* tidy the inter-proc to disconn the proxy proc */
4725 waitpid(pid, NULL, 0);
4726 tls_close(sx->cctx.tls_ctx, TLS_NO_SHUTDOWN);
4727 sx->cctx.tls_ctx = NULL;
4728 (void)close(sx->cctx.sock);
4730 continue_transport = NULL;
4731 continue_hostname = NULL;
4734 log_write(0, LOG_PANIC_DIE, "fork failed");
4740 /* If RSET failed and there are addresses left, they get deferred. */
4742 set_errno(sx->first_addr, errno, msg, DEFER, FALSE, host,
4743 #ifdef EXPERIMENTAL_DSN_INFO
4744 sx->smtp_greeting, sx->helo_response,
4746 &sx->delivery_start);
4750 /* End off tidily with QUIT unless the connection has died or the socket has
4751 been passed to another process. */
4755 { /* Use _MORE to get QUIT in FIN segment */
4756 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4758 if (sx->cctx.tls_ctx && sx->send_tlsclose)
4760 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
4761 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4763 tls_shutdown_wr(sx->cctx.tls_ctx);
4764 sx->send_tlsclose = FALSE;
4771 /* Close the socket, and return the appropriate value, first setting
4772 works because the NULL setting is passed back to the calling process, and
4773 remote_max_parallel is forced to 1 when delivering over an existing connection,
4775 If all went well and continue_more is set, we shouldn't actually get here if
4776 there are further addresses, as the return above will be taken. However,
4777 writing RSET might have failed, or there may be other addresses whose hosts are
4778 specified in the transports, and therefore not visible at top level, in which
4779 case continue_more won't get set. */
4783 /* This flushes data queued in the socket, being the QUIT and any TLS Close,
4784 sending them along with the client FIN flag. Us (we hope) sending FIN first
4785 means we (client) take the TIME_WAIT state, so the server (which likely has a
4786 higher connection rate) does not have to. */
4788 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4789 shutdown(sx->cctx.sock, SHUT_WR);
4792 if (sx->send_quit || tcw_done && !tcw)
4794 /* Wait for (we hope) ack of our QUIT, and a server FIN. Discard any data
4795 received, then discard the socket. Any packet received after then, or receive
4796 data still in the socket, will get a RST - hence the pause/drain. */
4798 /* Reap the response to QUIT, timing out after one second */
4799 (void) smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', 1);
4801 if (sx->cctx.tls_ctx)
4805 /* Reap the TLS Close Notify from the server, timing out after one second */
4806 sigalrm_seen = FALSE;
4809 n = tls_read(sx->cctx.tls_ctx, sx->inbuffer, sizeof(sx->inbuffer));
4810 while (!sigalrm_seen && n > 0);
4813 if (sx->send_tlsclose)
4815 # ifdef EXIM_TCP_CORK
4816 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4818 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4821 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WONLY);
4822 sx->cctx.tls_ctx = NULL;
4826 /* Drain any trailing data from the socket before close, to avoid sending a RST */
4828 if ( poll_one_fd(sx->cctx.sock, POLLIN, 20) != 0 /* 20ms */
4829 && fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4830 for (int i = 16, n; /* drain socket */
4831 (n = read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer))) > 0 && i > 0;
4832 i--) HDEBUG(D_transport|D_acl|D_v)
4835 debug_printf_indent(" SMTP(drain %d bytes)<< %.*s\n", n, m, sx->inbuffer);
4836 for (m = 0; m < n; m++)
4837 debug_printf("0x%02x\n", sx->inbuffer[m]);
4840 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4841 (void)close(sx->cctx.sock);
4843 continue_transport = NULL;
4844 continue_hostname = NULL;
4845 smtp_debug_cmd_report();
4847 #ifndef DISABLE_EVENT
4848 (void) event_raise(tblock->event_action, US"tcp:close", NULL, NULL);
4854 sx->first_addr = NULL;
4855 for (address_item * a = sx->addrlist->next; a; a = a->next)
4856 if (a->transport_return == DANE)
4858 a->transport_return = PENDING_DEFER;
4859 if (!sx->first_addr)
4861 /* Remember the new start-point in the addrlist, for smtp_setup_conn()
4862 to get the domain string for SNI */
4865 clearflag(a, af_cont_conn);
4866 setflag(a, af_new_conn); /* clear * from logging */
4867 DEBUG(D_transport) debug_printf("DANE: go-around for %s\n", a->domain);
4870 continue_sequence = 1; /* for consistency */
4875 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4876 if (mail_limit && sx->first_addr)
4878 /* Reset the sequence count since we closed the connection. This is flagged
4879 on the pipe back to the delivery process so that a non-continued-conn delivery
4882 continue_sequence = 1; /* for consistency */
4883 clearflag(sx->first_addr, af_cont_conn);
4884 setflag(sx->first_addr, af_new_conn); /* clear * from logging */
4893 if (dane_held) for (address_item * a = sx->addrlist->next; a; a = a->next)
4894 if (a->transport_return == DANE)
4895 a->transport_return = PENDING_DEFER;
4903 /*************************************************
4904 * Closedown entry point *
4905 *************************************************/
4907 /* This function is called when exim is passed an open smtp channel
4908 from another incarnation, but the message which it has been asked
4909 to deliver no longer exists. The channel is on stdin.
4911 We might do fancy things like looking for another message to send down
4912 the channel, but if the one we sought has gone, it has probably been
4913 delivered by some other process that itself will seek further messages,
4914 so just close down our connection.
4916 Argument: pointer to the transport instance block
4921 smtp_transport_closedown(transport_instance *tblock)
4923 smtp_transport_options_block * ob = SOB tblock->options_block;
4924 client_conn_ctx cctx;
4927 uschar inbuffer[4096];
4928 uschar outbuffer[16];
4930 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4931 cctx.sock = fileno(stdin);
4932 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4934 sx.inblock.cctx = &cctx;
4935 sx.inblock.buffer = inbuffer;
4936 sx.inblock.buffersize = sizeof(inbuffer);
4937 sx.inblock.ptr = inbuffer;
4938 sx.inblock.ptrend = inbuffer;
4940 sx.outblock.cctx = &cctx;
4941 sx.outblock.buffersize = sizeof(outbuffer);
4942 sx.outblock.buffer = outbuffer;
4943 sx.outblock.ptr = outbuffer;
4944 sx.outblock.cmd_count = 0;
4945 sx.outblock.authenticating = FALSE;
4947 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4948 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
4949 (void)close(cctx.sock);
4954 /*************************************************
4955 * Prepare addresses for delivery *
4956 *************************************************/
4958 /* This function is called to flush out error settings from previous delivery
4959 attempts to other hosts. It also records whether we got here via an MX record
4960 or not in the more_errno field of the address. We are interested only in
4961 addresses that are still marked DEFER - others may have got delivered to a
4962 previously considered IP address. Set their status to PENDING_DEFER to indicate
4963 which ones are relevant this time.
4966 addrlist the list of addresses
4967 host the host we are delivering to
4969 Returns: the first address for this delivery
4972 static address_item *
4973 prepare_addresses(address_item *addrlist, host_item *host)
4975 address_item *first_addr = NULL;
4976 for (address_item * addr = addrlist; addr; addr = addr->next)
4977 if (addr->transport_return == DEFER)
4979 if (!first_addr) first_addr = addr;
4980 addr->transport_return = PENDING_DEFER;
4981 addr->basic_errno = 0;
4982 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
4983 addr->message = NULL;
4985 addr->cipher = NULL;
4986 addr->ourcert = NULL;
4987 addr->peercert = NULL;
4988 addr->peerdn = NULL;
4989 addr->ocsp = OCSP_NOT_REQ;
4990 addr->tlsver = NULL;
4992 #ifdef EXPERIMENTAL_DSN_INFO
4993 addr->smtp_greeting = NULL;
4994 addr->helo_response = NULL;
5002 /*************************************************
5003 * Main entry point *
5004 *************************************************/
5006 /* See local README for interface details. As this is a remote transport, it is
5007 given a chain of addresses to be delivered in one connection, if possible. It
5008 always returns TRUE, indicating that each address has its own independent
5009 status set, except if there is a setting up problem, in which case it returns
5013 smtp_transport_entry(
5014 transport_instance *tblock, /* data for this instantiation */
5015 address_item *addrlist) /* addresses we are working on */
5018 int hosts_defer = 0;
5020 int hosts_looked_up = 0;
5021 int hosts_retry = 0;
5022 int hosts_serial = 0;
5023 int hosts_total = 0;
5024 int total_hosts_tried = 0;
5025 BOOL expired = TRUE;
5026 uschar *expanded_hosts = NULL;
5028 uschar *tid = string_sprintf("%s transport", tblock->name);
5029 smtp_transport_options_block *ob = SOB tblock->options_block;
5030 host_item *hostlist = addrlist->host_list;
5031 host_item *host = NULL;
5035 debug_printf("%s transport entered\n", tblock->name);
5036 for (address_item * addr = addrlist; addr; addr = addr->next)
5037 debug_printf(" %s\n", addr->address);
5040 debug_printf("hostlist:\n");
5041 for (host_item * host = hostlist; host; host = host->next)
5042 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
5044 if (continue_hostname)
5045 debug_printf("already connected to %s [%s] (on fd %d)\n",
5046 continue_hostname, continue_host_address,
5047 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
5050 /* Check the restrictions on line length */
5052 if (max_received_linelength > ob->message_linelength_limit)
5055 gettimeofday(&now, NULL);
5057 for (address_item * addr = addrlist; addr; addr = addr->next)
5058 if (addr->transport_return == DEFER)
5059 addr->transport_return = PENDING_DEFER;
5061 set_errno_nohost(addrlist, ERRNO_SMTPFORMAT,
5062 US"message has lines too long for transport", FAIL, TRUE, &now);
5066 /* Set the flag requesting that these hosts be added to the waiting
5067 database if the delivery fails temporarily or if we are running with
5068 queue_smtp or a 2-stage queue run. This gets unset for certain
5069 kinds of error, typically those that are specific to the message. */
5071 update_waiting = TRUE;
5073 /* If a host list is not defined for the addresses - they must all have the
5074 same one in order to be passed to a single transport - or if the transport has
5075 a host list with hosts_override set, use the host list supplied with the
5076 transport. It is an error for this not to exist. */
5078 if (!hostlist || (ob->hosts_override && ob->hosts))
5082 addrlist->message = string_sprintf("%s transport called with no hosts set",
5084 addrlist->transport_return = PANIC;
5085 return FALSE; /* Only top address has status */
5088 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
5091 /* If the transport's host list contains no '$' characters, and we are not
5092 randomizing, it is fixed and therefore a chain of hosts can be built once
5093 and for all, and remembered for subsequent use by other calls to this
5094 transport. If, on the other hand, the host list does contain '$', or we are
5095 randomizing its order, we have to rebuild it each time. In the fixed case,
5096 as the hosts string will never be used again, it doesn't matter that we
5097 replace all the : characters with zeros. */
5101 uschar *s = ob->hosts;
5103 if (Ustrchr(s, '$'))
5105 if (!(expanded_hosts = expand_string(s)))
5107 addrlist->message = string_sprintf("failed to expand list of hosts "
5108 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
5109 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
5110 return FALSE; /* Only top address has status */
5112 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
5113 "\"%s\"\n", s, expanded_hosts);
5117 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
5121 log_write(0, LOG_MAIN|LOG_PANIC,
5122 "attempt to use tainted host list '%s' from '%s' in transport %s",
5123 s, ob->hosts, tblock->name);
5124 /* Avoid leaking info to an attacker */
5125 addrlist->message = US"internal configuration error";
5126 addrlist->transport_return = PANIC;
5130 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
5132 /* Check that the expansion yielded something useful. */
5136 string_sprintf("%s transport has empty hosts setting", tblock->name);
5137 addrlist->transport_return = PANIC;
5138 return FALSE; /* Only top address has status */
5141 /* If there was no expansion of hosts, save the host list for
5144 if (!expanded_hosts) ob->hostlist = hostlist;
5147 /* This is not the first time this transport has been run in this delivery;
5148 the host list was built previously. */
5151 hostlist = ob->hostlist;
5154 /* The host list was supplied with the address. If hosts_randomize is set, we
5155 must sort it into a random order if it did not come from MX records and has not
5156 already been randomized (but don't bother if continuing down an existing
5159 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
5161 host_item *newlist = NULL;
5164 host_item *h = hostlist;
5165 hostlist = hostlist->next;
5167 h->sort_key = random_number(100);
5174 else if (h->sort_key < newlist->sort_key)
5181 host_item *hh = newlist;
5184 if (h->sort_key < hh->next->sort_key) break;
5192 hostlist = addrlist->host_list = newlist;
5195 /* Sort out the default port. */
5197 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
5199 /* For each host-plus-IP-address on the list:
5201 . If this is a continued delivery and the host isn't the one with the
5202 current connection, skip.
5204 . If the status is unusable (i.e. previously failed or retry checked), skip.
5206 . If no IP address set, get the address, either by turning the name into
5207 an address, calling gethostbyname if gethostbyname is on, or by calling
5208 the DNS. The DNS may yield multiple addresses, in which case insert the
5209 extra ones into the list.
5211 . Get the retry data if not previously obtained for this address and set the
5212 field which remembers the state of this address. Skip if the retry time is
5213 not reached. If not, remember whether retry data was found. The retry string
5214 contains both the name and the IP address.
5216 . Scan the list of addresses and mark those whose status is DEFER as
5217 PENDING_DEFER. These are the only ones that will be processed in this cycle
5220 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
5221 Some addresses may be successfully delivered, others may fail, and yet
5222 others may get temporary errors and so get marked DEFER.
5224 . The return from the delivery attempt is OK if a connection was made and a
5225 valid SMTP dialogue was completed. Otherwise it is DEFER.
5227 . If OK, add a "remove" retry item for this host/IPaddress, if any.
5229 . If fail to connect, or other defer state, add a retry item.
5231 . If there are any addresses whose status is still DEFER, carry on to the
5232 next host/IPaddress, unless we have tried the number of hosts given
5233 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
5234 there is some fancy logic for hosts_max_try that means its limit can be
5235 overstepped in some circumstances.
5237 If we get to the end of the list, all hosts have deferred at least one address,
5238 or not reached their retry times. If delay_after_cutoff is unset, it requests a
5239 delivery attempt to those hosts whose last try was before the arrival time of
5240 the current message. To cope with this, we have to go round the loop a second
5241 time. After that, set the status and error data for any addresses that haven't
5242 had it set already. */
5244 for (int cutoff_retry = 0;
5245 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
5248 host_item *nexthost = NULL;
5249 int unexpired_hosts_tried = 0;
5250 BOOL continue_host_tried = FALSE;
5252 retry_non_continued:
5253 for (host = hostlist;
5255 && unexpired_hosts_tried < ob->hosts_max_try
5256 && total_hosts_tried < ob->hosts_max_try_hardlimit;
5261 BOOL host_is_expired = FALSE;
5262 BOOL message_defer = FALSE;
5263 BOOL some_deferred = FALSE;
5264 address_item *first_addr = NULL;
5265 uschar *interface = NULL;
5266 uschar *retry_host_key = NULL;
5267 uschar *retry_message_key = NULL;
5268 uschar *serialize_key = NULL;
5270 /* Default next host is next host. :-) But this can vary if the
5271 hosts_max_try limit is hit (see below). It may also be reset if a host
5272 address is looked up here (in case the host was multihomed). */
5274 nexthost = host->next;
5276 /* If the address hasn't yet been obtained from the host name, look it up
5277 now, unless the host is already marked as unusable. If it is marked as
5278 unusable, it means that the router was unable to find its IP address (in
5279 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
5280 the lookup failed last time. We don't get this far if *all* MX records
5281 point to non-existent hosts; that is treated as a hard error.
5283 We can just skip this host entirely. When the hosts came from the router,
5284 the address will timeout based on the other host(s); when the address is
5285 looked up below, there is an explicit retry record added.
5287 Note that we mustn't skip unusable hosts if the address is not unset; they
5288 may be needed as expired hosts on the 2nd time round the cutoff loop. */
5292 int new_port, flags;
5294 if (host->status >= hstatus_unusable)
5296 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
5301 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
5303 /* The host name is permitted to have an attached port. Find it, and
5304 strip it from the name. Just remember it for now. */
5306 new_port = host_item_get_port(host);
5308 /* Count hosts looked up */
5312 /* Find by name if so configured, or if it's an IP address. We don't
5313 just copy the IP address, because we need the test-for-local to happen. */
5315 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
5316 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
5317 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
5319 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
5320 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
5322 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
5323 &ob->dnssec, /* domains for request/require */
5326 /* Update the host (and any additional blocks, resulting from
5327 multihoming) with a host-specific port, if any. */
5329 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
5331 /* Failure to find the host at this time (usually DNS temporary failure)
5332 is really a kind of routing failure rather than a transport failure.
5333 Therefore we add a retry item of the routing kind, not to stop us trying
5334 to look this name up here again, but to ensure the address gets timed
5335 out if the failures go on long enough. A complete failure at this point
5336 commonly points to a configuration error, but the best action is still
5337 to carry on for the next host. */
5339 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
5341 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
5343 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
5344 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
5345 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
5346 host->status = hstatus_unusable;
5348 for (address_item * addr = addrlist; addr; addr = addr->next)
5350 if (addr->transport_return != DEFER) continue;
5351 addr->basic_errno = ERRNO_UNKNOWNHOST;
5352 addr->message = string_sprintf(
5353 rc == HOST_FIND_SECURITY
5354 ? "lookup of IP address for %s was insecure"
5355 : "failed to lookup IP address for %s",
5361 /* If the host is actually the local host, we may have a problem, or
5362 there may be some cunning configuration going on. In the problem case,
5363 log things and give up. The default transport status is already DEFER. */
5365 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
5367 for (address_item * addr = addrlist; addr; addr = addr->next)
5369 addr->basic_errno = ERRNO_HOST_IS_LOCAL;
5370 addr->message = string_sprintf("%s transport found host %s to be "
5371 "local", tblock->name, host->name);
5375 } /* End of block for IP address lookup */
5377 /* If this is a continued delivery, we are interested only in the host
5378 which matches the name of the existing open channel. The check is put
5379 here after the local host lookup, in case the name gets expanded as a
5380 result of the lookup. Set expired FALSE, to save the outer loop executing
5383 if (continue_hostname)
5384 if ( Ustrcmp(continue_hostname, host->name) != 0
5385 || Ustrcmp(continue_host_address, host->address) != 0
5389 continue; /* With next host */
5392 continue_host_tried = TRUE;
5394 /* Reset the default next host in case a multihomed host whose addresses
5395 are not looked up till just above added to the host list. */
5397 nexthost = host->next;
5399 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
5400 domain is in queue_smtp_domains, we don't actually want to attempt any
5401 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
5402 there is a lookup defer in queue_smtp_domains, proceed as if the domain
5403 were not in it. We don't want to hold up all SMTP deliveries! Except when
5404 doing a two-stage queue run, don't do this if forcing. */
5406 if ( (!f.deliver_force || f.queue_2stage)
5408 || match_isinlist(addrlist->domain,
5409 CUSS &queue_smtp_domains, 0,
5410 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK)
5413 DEBUG(D_transport) debug_printf("first-pass routing only\n");
5415 for (address_item * addr = addrlist; addr; addr = addr->next)
5416 if (addr->transport_return == DEFER)
5417 addr->message = US"first-pass only routing due to -odqs, "
5418 "queue_smtp_domains or control=queue";
5419 continue; /* With next host */
5422 /* Count hosts being considered - purely for an intelligent comment
5423 if none are usable. */
5427 /* Set $host and $host address now in case they are needed for the
5428 interface expansion or the serialize_hosts check; they remain set if an
5429 actual delivery happens. */
5431 deliver_host = host->name;
5432 deliver_host_address = host->address;
5433 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
5434 : host->dnssec == DS_NO ? US"no"
5437 /* Set up a string for adding to the retry key if the port number is not
5438 the standard SMTP port. A host may have its own port setting that overrides
5441 pistring = string_sprintf(":%d", host->port == PORT_NONE
5442 ? defport : host->port);
5443 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
5445 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
5446 string is set, even if constant (as different transports can have different
5447 constant settings), we must add it to the key that is used for retries,
5448 because connections to the same host from a different interface should be
5449 treated separately. */
5451 host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
5453 uschar * s = ob->interface;
5456 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
5458 pistring = string_sprintf("%s/%s", pistring, interface);
5462 /* The first time round the outer loop, check the status of the host by
5463 inspecting the retry data. The second time round, we are interested only
5464 in expired hosts that haven't been tried since this message arrived. */
5466 if (cutoff_retry == 0)
5469 /* Ensure the status of the address is set by checking retry data if
5470 necessary. There may be host-specific retry data (applicable to all
5471 messages) and also data for retries of a specific message at this host.
5472 If either of these retry records are actually read, the keys used are
5473 returned to save recomputing them later. */
5475 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5476 US"retry_include_ip_address", ob->retry_include_ip_address,
5477 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5478 continue; /* with next host */
5480 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
5481 incl_ip, &retry_host_key, &retry_message_key);
5483 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
5484 host->address ? host->address : US"", pistring,
5485 host->status == hstatus_usable ? "usable"
5486 : host->status == hstatus_unusable ? "unusable"
5487 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
5489 /* Skip this address if not usable at this time, noting if it wasn't
5490 actually expired, both locally and in the address. */
5492 switch (host->status)
5494 case hstatus_unusable:
5496 setflag(addrlist, af_retry_skipped);
5499 case hstatus_unusable_expired:
5502 case hwhy_retry: hosts_retry++; break;
5503 case hwhy_failed: hosts_fail++; break;
5505 case hwhy_deferred: hosts_defer++; break;
5508 /* If there was a retry message key, implying that previously there
5509 was a message-specific defer, we don't want to update the list of
5510 messages waiting for these hosts. */
5512 if (retry_message_key) update_waiting = FALSE;
5513 continue; /* With the next host or IP address */
5517 /* Second time round the loop: if the address is set but expired, and
5518 the message is newer than the last try, let it through. */
5523 || host->status != hstatus_unusable_expired
5524 || host->last_try > received_time.tv_sec)
5526 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
5527 host->name, host->address, pistring);
5528 host_is_expired = TRUE;
5531 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
5532 it remains TRUE only if all hosts are expired and none are actually tried.
5537 /* If this host is listed as one to which access must be serialized,
5538 see if another Exim process has a connection to it, and if so, skip
5539 this host. If not, update the database to record our connection to it
5540 and remember this for later deletion. Do not do any of this if we are
5541 sending the message down a pre-existing connection. */
5543 if ( !continue_hostname
5544 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
5546 serialize_key = string_sprintf("host-serialize-%s", host->name);
5547 if (!enq_start(serialize_key, 1))
5550 debug_printf("skipping host %s because another Exim process "
5551 "is connected to it\n", host->name);
5557 /* OK, we have an IP address that is not waiting for its retry time to
5558 arrive (it might be expired) OR (second time round the loop) we have an
5559 expired host that hasn't been tried since the message arrived. Have a go
5560 at delivering the message to it. First prepare the addresses by flushing
5561 out the result of previous attempts, and finding the first address that
5562 is still to be delivered. */
5564 first_addr = prepare_addresses(addrlist, host);
5566 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5567 message_id, host->name, host->address, addrlist->address,
5568 addrlist->next ? ", ..." : "");
5570 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5571 message_id, host->name, host->address, pistring, addrlist->address,
5572 addrlist->next ? ", ..." : "");
5574 /* This is not for real; don't do the delivery. If there are
5575 any remaining hosts, list them. */
5580 gettimeofday(&now, NULL);
5581 set_errno_nohost(addrlist, 0, NULL, OK, FALSE, &now);
5582 for (address_item * addr = addrlist; addr; addr = addr->next)
5584 addr->host_used = host;
5585 addr->special_action = '*';
5586 addr->message = US"delivery bypassed by -N option";
5590 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5591 "*** host and remaining hosts:\n", tblock->name);
5592 for (host_item * host2 = host; host2; host2 = host2->next)
5593 debug_printf(" %s [%s]\n", host2->name,
5594 host2->address ? host2->address : US"unset");
5599 /* This is for real. If the host is expired, we don't count it for
5600 hosts_max_retry. This ensures that all hosts must expire before an address
5601 is timed out, unless hosts_max_try_hardlimit (which protects against
5602 lunatic DNS configurations) is reached.
5604 If the host is not expired and we are about to hit the hosts_max_retry
5605 limit, check to see if there is a subsequent hosts with a different MX
5606 value. If so, make that the next host, and don't count this one. This is a
5607 heuristic to make sure that different MXs do get tried. With a normal kind
5608 of retry rule, they would get tried anyway when the earlier hosts were
5609 delayed, but if the domain has a "retry every time" type of rule - as is
5610 often used for the the very large ISPs, that won't happen. */
5615 /* Make a copy of the host if it is local to this invocation
5616 of the transport. */
5620 thost = store_get(sizeof(host_item), GET_UNTAINTED);
5622 thost->name = string_copy(host->name);
5623 thost->address = string_copy(host->address);
5628 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5631 debug_printf("hosts_max_try limit reached with this host\n");
5632 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5635 unexpired_hosts_tried--;
5636 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5637 "and will be tried\n");
5642 /* Attempt the delivery. */
5644 total_hosts_tried++;
5645 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5646 &message_defer, FALSE);
5649 OK => connection made, each address contains its result;
5650 message_defer is set for message-specific defers (when all
5651 recipients are marked defer)
5652 DEFER => there was a non-message-specific delivery problem;
5653 ERROR => there was a problem setting up the arguments for a filter,
5654 or there was a problem with expanding added headers
5657 /* If the result is not OK, there was a non-message-specific problem.
5658 If the result is DEFER, we need to write to the logs saying what happened
5659 for this particular host, except in the case of authentication and TLS
5660 failures, where the log has already been written. If all hosts defer a
5661 general message is written at the end. */
5663 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5664 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5665 write_logs(host, first_addr->message, first_addr->basic_errno);
5667 #ifndef DISABLE_EVENT
5669 deferred_event_raise(first_addr, host, US"msg:host:defer");
5672 /* If STARTTLS was accepted, but there was a failure in setting up the
5673 TLS session (usually a certificate screwup), and the host is not in
5674 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5675 TLS forcibly turned off. We have to start from scratch with a new SMTP
5676 connection. That's why the retry is done from here, not from within
5677 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5678 session, so the in-clear transmission after those errors, if permitted,
5679 happens inside smtp_deliver().] */
5683 && first_addr->basic_errno == ERRNO_TLSFAILURE
5684 && ob->tls_tempfail_tryclear
5685 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5688 log_write(0, LOG_MAIN,
5689 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5690 first_addr->message, host->name, host->address);
5691 first_addr = prepare_addresses(addrlist, host);
5692 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5693 &message_defer, TRUE);
5694 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5695 write_logs(host, first_addr->message, first_addr->basic_errno);
5696 # ifndef DISABLE_EVENT
5698 deferred_event_raise(first_addr, host, US"msg:host:defer");
5701 #endif /*DISABLE_TLS*/
5703 #ifndef DISABLE_EVENT
5704 /* If the last host gave a defer raise a per-message event */
5707 && unexpired_hosts_tried < ob->hosts_max_try
5708 && total_hosts_tried < ob->hosts_max_try_hardlimit
5710 && (message_defer || rc == DEFER)
5712 deferred_event_raise(first_addr, host, US"msg:defer");
5716 /* Delivery attempt finished */
5718 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5719 message_id, host->name, host->address, pistring, addrlist->address,
5720 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5722 /* Release serialization if set up */
5724 if (serialize_key) enq_end(serialize_key);
5726 /* If the result is DEFER, or if a host retry record is known to exist, we
5727 need to add an item to the retry chain for updating the retry database
5728 at the end of delivery. We only need to add the item to the top address,
5729 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5730 for any other delivery attempts using the same address. (It is copied into
5731 the unusable tree at the outer level, so even if different address blocks
5732 contain the same address, it still won't get tried again.) */
5734 if (rc == DEFER || retry_host_key)
5736 int delete_flag = rc != DEFER ? rf_delete : 0;
5737 if (!retry_host_key)
5740 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5741 US"retry_include_ip_address", ob->retry_include_ip_address,
5742 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5743 incl_ip = TRUE; /* error; use most-specific retry record */
5745 retry_host_key = incl_ip
5746 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5747 : string_sprintf("T:%S%s", host->name, pistring);
5750 /* If a delivery of another message over an existing SMTP connection
5751 yields DEFER, we do NOT set up retry data for the host. This covers the
5752 case when there are delays in routing the addresses in the second message
5753 that are so long that the server times out. This is alleviated by not
5754 routing addresses that previously had routing defers when handling an
5755 existing connection, but even so, this case may occur (e.g. if a
5756 previously happily routed address starts giving routing defers). If the
5757 host is genuinely down, another non-continued message delivery will
5758 notice it soon enough. */
5760 if (delete_flag != 0 || !continue_hostname)
5761 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5763 /* We may have tried an expired host, if its retry time has come; ensure
5764 the status reflects the expiry for the benefit of any other addresses. */
5768 host->status = host_is_expired
5769 ? hstatus_unusable_expired : hstatus_unusable;
5770 host->why = hwhy_deferred;
5774 /* If message_defer is set (host was OK, but every recipient got deferred
5775 because of some message-specific problem), or if that had happened
5776 previously so that a message retry key exists, add an appropriate item
5777 to the retry chain. Note that if there was a message defer but now there is
5778 a host defer, the message defer record gets deleted. That seems perfectly
5779 reasonable. Also, stop the message from being remembered as waiting
5780 for specific hosts. */
5782 if (message_defer || retry_message_key)
5784 int delete_flag = message_defer ? 0 : rf_delete;
5785 if (!retry_message_key)
5788 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5789 US"retry_include_ip_address", ob->retry_include_ip_address,
5790 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5791 incl_ip = TRUE; /* error; use most-specific retry record */
5793 retry_message_key = incl_ip
5794 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5796 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5798 retry_add_item(addrlist, retry_message_key,
5799 rf_message | rf_host | delete_flag);
5800 update_waiting = FALSE;
5803 /* Any return other than DEFER (that is, OK or ERROR) means that the
5804 addresses have got their final statuses filled in for this host. In the OK
5805 case, see if any of them are deferred. */
5808 for (address_item * addr = addrlist; addr; addr = addr->next)
5809 if (addr->transport_return == DEFER)
5811 some_deferred = TRUE;
5815 /* If no addresses deferred or the result was ERROR, return. We do this for
5816 ERROR because a failing filter set-up or add_headers expansion is likely to
5817 fail for any host we try. */
5819 if (rc == ERROR || (rc == OK && !some_deferred))
5821 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5822 return TRUE; /* Each address has its status */
5825 /* If the result was DEFER or some individual addresses deferred, let
5826 the loop run to try other hosts with the deferred addresses, except for the
5827 case when we were trying to deliver down an existing channel and failed.
5828 Don't try any other hosts in this case. */
5830 if (continue_hostname) break;
5832 /* If the whole delivery, or some individual addresses, were deferred and
5833 there are more hosts that could be tried, do not count this host towards
5834 the hosts_max_try limit if the age of the message is greater than the
5835 maximum retry time for this host. This means we may try try all hosts,
5836 ignoring the limit, when messages have been around for some time. This is
5837 important because if we don't try all hosts, the address will never time
5838 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5840 if ((rc == DEFER || some_deferred) && nexthost)
5843 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5845 if (retry && retry->rules)
5847 retry_rule *last_rule;
5848 for (last_rule = retry->rules;
5850 last_rule = last_rule->next);
5851 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5853 else timedout = TRUE; /* No rule => timed out */
5857 unexpired_hosts_tried--;
5858 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5859 "hosts_max_try (message older than host's retry time)\n");
5865 if (unexpired_hosts_tried >= ob->hosts_max_try)
5866 debug_printf("reached transport hosts_max_try limit %d\n",
5868 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5869 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5870 ob->hosts_max_try_hardlimit);
5873 testharness_pause_ms(500); /* let server debug out */
5874 } /* End of loop for trying multiple hosts. */
5876 /* If we failed to find a matching host in the list, for an already-open
5877 connection, just close it and start over with the list. This can happen
5878 for routing that changes from run to run, or big multi-IP sites with
5881 if (continue_hostname && !continue_host_tried)
5883 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5885 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5887 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5889 /*XXX doublecheck that! */
5891 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5893 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5894 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5895 cutthrough.cctx.tls_ctx = NULL;
5896 cutthrough.is_tls = FALSE;
5900 (void) write(fd, US"QUIT\r\n", 6);
5903 cutthrough.cctx.sock = -1;
5904 continue_hostname = NULL;
5905 goto retry_non_continued;
5908 /* This is the end of the loop that repeats iff expired is TRUE and
5909 ob->delay_after_cutoff is FALSE. The second time round we will
5910 try those hosts that haven't been tried since the message arrived. */
5914 debug_printf("all IP addresses skipped or deferred at least one address\n");
5915 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5916 debug_printf("retrying IP addresses not tried since message arrived\n");
5921 /* Get here if all IP addresses are skipped or defer at least one address. In
5922 MUA wrapper mode, this will happen only for connection or other non-message-
5923 specific failures. Force the delivery status for all addresses to FAIL. */
5927 for (address_item * addr = addrlist; addr; addr = addr->next)
5928 addr->transport_return = FAIL;
5932 /* In the normal, non-wrapper case, add a standard message to each deferred
5933 address if there hasn't been an error, that is, if it hasn't actually been
5934 tried this time. The variable "expired" will be FALSE if any deliveries were
5935 actually tried, or if there was at least one host that was not expired. That
5936 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
5937 a delivery has been tried, an error code will be set, and the failing of the
5938 message is handled by the retry code later.
5940 If queue_smtp is set, or this transport was called to send a subsequent message
5941 down an existing TCP/IP connection, and something caused the host not to be
5942 found, we end up here, but can detect these cases and handle them specially. */
5944 for (address_item * addr = addrlist; addr; addr = addr->next)
5946 /* If host is not NULL, it means that we stopped processing the host list
5947 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
5948 means we need to behave as if some hosts were skipped because their retry
5949 time had not come. Specifically, this prevents the address from timing out.
5950 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
5951 hosts were tried. */
5954 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5957 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
5958 "hosts were tried\n");
5963 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
5964 setflag(addr, af_retry_skipped);
5967 if (f.queue_smtp) /* no deliveries attempted */
5969 addr->transport_return = DEFER;
5970 addr->basic_errno = 0;
5971 addr->message = US"SMTP delivery explicitly queued";
5974 else if ( addr->transport_return == DEFER
5975 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
5979 addr->basic_errno = ERRNO_HRETRY;
5980 if (continue_hostname)
5981 addr->message = US"no host found for existing SMTP connection";
5984 setflag(addr, af_pass_message); /* This is not a security risk */
5985 addr->message = string_sprintf(
5986 "all hosts%s have been failing for a long time %s",
5987 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
5988 ob->delay_after_cutoff
5989 ? US"(and retry time not reached)"
5990 : US"and were last tried after this message arrived");
5992 /* If we are already using fallback hosts, or there are no fallback hosts
5993 defined, convert the result to FAIL to cause a bounce. */
5995 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
5996 addr->transport_return = FAIL;
6001 if (hosts_retry == hosts_total)
6002 s = "retry time not reached for any host%s";
6003 else if (hosts_fail == hosts_total)
6004 s = "all host address lookups%s failed permanently";
6005 else if (hosts_defer == hosts_total)
6006 s = "all host address lookups%s failed temporarily";
6007 else if (hosts_serial == hosts_total)
6008 s = "connection limit reached for all hosts%s";
6009 else if (hosts_fail+hosts_defer == hosts_total)
6010 s = "all host address lookups%s failed";
6012 s = "some host address lookups failed and retry time "
6013 "not reached for other hosts or connection limit reached%s";
6015 addr->message = string_sprintf(s,
6016 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
6021 /* Update the database which keeps information about which messages are waiting
6022 for which hosts to become available. For some message-specific errors, the
6023 update_waiting flag is turned off because we don't want follow-on deliveries in
6024 those cases. If this transport instance is explicitly limited to one message
6025 per connection then follow-on deliveries are not possible and there's no need
6026 to create/update the per-transport wait-<transport_name> database. */
6028 if (update_waiting && tblock->connection_max_messages != 1)
6029 transport_update_waiting(hostlist, tblock->name);
6033 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
6035 return TRUE; /* Each address has its status */
6038 #endif /*!MACRO_PREDEF*/
6041 /* End of transport/smtp.c */