1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) The Exim Maintainers 2020 - 2022 */
6 /* Copyright (c) University of Cambridge 1995 - 2018 */
7 /* See the file NOTICE for conditions of use and distribution. */
8 /* SPDX-License-Identifier: GPL-2.0-or-later */
13 #if defined(SUPPORT_DANE) && defined(DISABLE_TLS)
14 # error TLS is required for DANE
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 #define LOFF(field) OPT_OFF(smtp_transport_options_block, field)
25 optionlist smtp_transport_options[] = {
26 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
27 OPT_OFF(transport_instance, expand_multi_domain) },
28 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
29 LOFF(expand_retry_include_ip_address) },
31 { "address_retry_include_sender", opt_bool,
32 LOFF(address_retry_include_sender) },
33 { "allow_localhost", opt_bool, LOFF(allow_localhost) },
34 #ifdef EXPERIMENTAL_ARC
35 { "arc_sign", opt_stringptr, LOFF(arc_sign) },
37 { "authenticated_sender", opt_stringptr, LOFF(authenticated_sender) },
38 { "authenticated_sender_force", opt_bool, LOFF(authenticated_sender_force) },
39 { "command_timeout", opt_time, LOFF(command_timeout) },
40 { "connect_timeout", opt_time, LOFF(connect_timeout) },
41 { "connection_max_messages", opt_int | opt_public,
42 OPT_OFF(transport_instance, connection_max_messages) },
44 { "dane_require_tls_ciphers", opt_stringptr, LOFF(dane_require_tls_ciphers) },
46 { "data_timeout", opt_time, LOFF(data_timeout) },
47 { "delay_after_cutoff", opt_bool, LOFF(delay_after_cutoff) },
49 { "dkim_canon", opt_stringptr, LOFF(dkim.dkim_canon) },
50 { "dkim_domain", opt_stringptr, LOFF(dkim.dkim_domain) },
51 { "dkim_hash", opt_stringptr, LOFF(dkim.dkim_hash) },
52 { "dkim_identity", opt_stringptr, LOFF(dkim.dkim_identity) },
53 { "dkim_private_key", opt_stringptr, LOFF(dkim.dkim_private_key) },
54 { "dkim_selector", opt_stringptr, LOFF(dkim.dkim_selector) },
55 { "dkim_sign_headers", opt_stringptr, LOFF(dkim.dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr, LOFF(dkim.dkim_strict) },
57 { "dkim_timestamps", opt_stringptr, LOFF(dkim.dkim_timestamps) },
59 { "dns_qualify_single", opt_bool, LOFF(dns_qualify_single) },
60 { "dns_search_parents", opt_bool, LOFF(dns_search_parents) },
61 { "dnssec_request_domains", opt_stringptr, LOFF(dnssec.request) },
62 { "dnssec_require_domains", opt_stringptr, LOFF(dnssec.require) },
63 { "dscp", opt_stringptr, LOFF(dscp) },
64 { "fallback_hosts", opt_stringptr, LOFF(fallback_hosts) },
65 { "final_timeout", opt_time, LOFF(final_timeout) },
66 { "gethostbyname", opt_bool, LOFF(gethostbyname) },
67 { "helo_data", opt_stringptr, LOFF(helo_data) },
68 #if !defined(DISABLE_TLS) && !defined(DISABLE_TLS_RESUME)
69 { "host_name_extract", opt_stringptr, LOFF(host_name_extract) },
71 { "hosts", opt_stringptr, LOFF(hosts) },
72 { "hosts_avoid_esmtp", opt_stringptr, LOFF(hosts_avoid_esmtp) },
73 { "hosts_avoid_pipelining", opt_stringptr, LOFF(hosts_avoid_pipelining) },
75 { "hosts_avoid_tls", opt_stringptr, LOFF(hosts_avoid_tls) },
77 { "hosts_max_try", opt_int, LOFF(hosts_max_try) },
78 { "hosts_max_try_hardlimit", opt_int, LOFF(hosts_max_try_hardlimit) },
80 { "hosts_nopass_tls", opt_stringptr, LOFF(hosts_nopass_tls) },
81 { "hosts_noproxy_tls", opt_stringptr, LOFF(hosts_noproxy_tls) },
83 { "hosts_override", opt_bool, LOFF(hosts_override) },
84 #ifndef DISABLE_PIPE_CONNECT
85 { "hosts_pipe_connect", opt_stringptr, LOFF(hosts_pipe_connect) },
87 { "hosts_randomize", opt_bool, LOFF(hosts_randomize) },
88 #if !defined(DISABLE_TLS) && !defined(DISABLE_OCSP)
89 { "hosts_request_ocsp", opt_stringptr, LOFF(hosts_request_ocsp) },
91 { "hosts_require_alpn", opt_stringptr, LOFF(hosts_require_alpn) },
92 { "hosts_require_auth", opt_stringptr, LOFF(hosts_require_auth) },
95 { "hosts_require_dane", opt_stringptr, LOFF(hosts_require_dane) },
98 { "hosts_require_ocsp", opt_stringptr, LOFF(hosts_require_ocsp) },
100 { "hosts_require_tls", opt_stringptr, LOFF(hosts_require_tls) },
102 { "hosts_try_auth", opt_stringptr, LOFF(hosts_try_auth) },
103 { "hosts_try_chunking", opt_stringptr, LOFF(hosts_try_chunking) },
105 { "hosts_try_dane", opt_stringptr, LOFF(hosts_try_dane) },
107 { "hosts_try_fastopen", opt_stringptr, LOFF(hosts_try_fastopen) },
109 { "hosts_try_prdr", opt_stringptr, LOFF(hosts_try_prdr) },
112 { "hosts_verify_avoid_tls", opt_stringptr, LOFF(hosts_verify_avoid_tls) },
114 { "interface", opt_stringptr, LOFF(interface) },
115 { "keepalive", opt_bool, LOFF(keepalive) },
116 { "lmtp_ignore_quota", opt_bool, LOFF(lmtp_ignore_quota) },
117 { "max_rcpt", opt_stringptr | opt_public,
118 OPT_OFF(transport_instance, max_addresses) },
119 { "message_linelength_limit", opt_int, LOFF(message_linelength_limit) },
120 { "multi_domain", opt_expand_bool | opt_public,
121 OPT_OFF(transport_instance, multi_domain) },
122 { "port", opt_stringptr, LOFF(port) },
123 { "protocol", opt_stringptr, LOFF(protocol) },
124 { "retry_include_ip_address", opt_expand_bool, LOFF(retry_include_ip_address) },
125 { "serialize_hosts", opt_stringptr, LOFF(serialize_hosts) },
126 { "size_addition", opt_int, LOFF(size_addition) },
128 { "socks_proxy", opt_stringptr, LOFF(socks_proxy) },
131 { "tls_alpn", opt_stringptr, LOFF(tls_alpn) },
132 { "tls_certificate", opt_stringptr, LOFF(tls_certificate) },
133 { "tls_crl", opt_stringptr, LOFF(tls_crl) },
134 { "tls_dh_min_bits", opt_int, LOFF(tls_dh_min_bits) },
135 { "tls_privatekey", opt_stringptr, LOFF(tls_privatekey) },
136 { "tls_require_ciphers", opt_stringptr, LOFF(tls_require_ciphers) },
137 # ifndef DISABLE_TLS_RESUME
138 { "tls_resumption_hosts", opt_stringptr, LOFF(tls_resumption_hosts) },
140 { "tls_sni", opt_stringptr, LOFF(tls_sni) },
141 { "tls_tempfail_tryclear", opt_bool, LOFF(tls_tempfail_tryclear) },
142 { "tls_try_verify_hosts", opt_stringptr, LOFF(tls_try_verify_hosts) },
143 { "tls_verify_cert_hostnames", opt_stringptr, LOFF(tls_verify_cert_hostnames)},
144 { "tls_verify_certificates", opt_stringptr, LOFF(tls_verify_certificates) },
145 { "tls_verify_hosts", opt_stringptr, LOFF(tls_verify_hosts) },
148 { "utf8_downconvert", opt_stringptr, LOFF(utf8_downconvert) },
152 /* Size of the options list. An extern variable has to be used so that its
153 address can appear in the tables drtables.c. */
155 int smtp_transport_options_count = nelem(smtp_transport_options);
161 smtp_transport_options_block smtp_transport_option_defaults = {0};
162 void smtp_transport_init(transport_instance *tblock) {}
163 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
164 void smtp_transport_closedown(transport_instance *tblock) {}
166 #else /*!MACRO_PREDEF*/
169 /* Default private options block for the smtp transport. */
171 smtp_transport_options_block smtp_transport_option_defaults = {
172 /* All non-mentioned elements 0/NULL/FALSE */
173 .helo_data = US"$primary_hostname",
174 .protocol = US"smtp",
175 .hosts_try_chunking = US"*",
177 .hosts_try_dane = US"*",
179 .hosts_try_fastopen = US"*",
181 .hosts_try_prdr = US"*",
184 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
186 .command_timeout = 5*60,
187 .connect_timeout = 5*60,
188 .data_timeout = 5*60,
189 .final_timeout = 10*60,
190 .size_addition = 1024,
192 .hosts_max_try_hardlimit = 50,
193 .message_linelength_limit = 998,
194 .address_retry_include_sender = TRUE,
195 .dns_qualify_single = TRUE,
196 .dnssec = { .request= US"*", .require=NULL },
197 .delay_after_cutoff = TRUE,
199 .retry_include_ip_address = TRUE,
201 .tls_verify_certificates = US"system",
202 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
203 .tls_tempfail_tryclear = TRUE,
204 .tls_try_verify_hosts = US"*",
205 .tls_verify_cert_hostnames = US"*",
206 # ifndef DISABLE_TLS_RESUME
207 .host_name_extract = US"${if and {{match{$host}{.outlook.com\\$}} {match{$item}{\\N^250-([\\w.]+)\\s\\N}}} {$1}}",
211 .utf8_downconvert = US"-1",
215 { .dkim_hash = US"sha256", },
219 /* some DSN flags for use later */
221 static int rf_list[] = {rf_notify_never, rf_notify_success,
222 rf_notify_failure, rf_notify_delay };
224 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
230 static uschar *smtp_command; /* Points to last cmd for error messages */
231 static uschar *mail_command; /* Points to MAIL cmd for error messages */
232 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
233 static BOOL update_waiting; /* TRUE to update the "wait" database */
235 /*XXX move to smtp_context */
236 static BOOL pipelining_active; /* current transaction is in pipe mode */
239 static unsigned ehlo_response(uschar * buf, unsigned checks);
242 /******************************************************************************/
245 smtp_deliver_init(void)
249 const pcre2_code ** re;
250 const uschar * string;
253 { ®ex_AUTH, AUTHS_REGEX },
254 { ®ex_CHUNKING, US"\\n250[\\s\\-]CHUNKING(\\s|\\n|$)" },
255 { ®ex_DSN, US"\\n250[\\s\\-]DSN(\\s|\\n|$)" },
256 { ®ex_IGNOREQUOTA, US"\\n250[\\s\\-]IGNOREQUOTA(\\s|\\n|$)" },
257 { ®ex_PIPELINING, US"\\n250[\\s\\-]PIPELINING(\\s|\\n|$)" },
258 { ®ex_SIZE, US"\\n250[\\s\\-]SIZE(\\s|\\n|$)" },
261 { ®ex_STARTTLS, US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)" },
264 { ®ex_PRDR, US"\\n250[\\s\\-]PRDR(\\s|\\n|$)" },
267 { ®ex_UTF8, US"\\n250[\\s\\-]SMTPUTF8(\\s|\\n|$)" },
269 #ifndef DISABLE_PIPE_CONNECT
270 { ®ex_EARLY_PIPE, US"\\n250[\\s\\-]" EARLY_PIPE_FEATURE_NAME "(\\s|\\n|$)" },
272 #ifdef EXPERIMENTAL_ESMTP_LIMITS
273 { ®ex_LIMITS, US"\\n250[\\s\\-]LIMITS\\s" },
277 for (struct list * l = list; l < list + nelem(list); l++)
279 *l->re = regex_must_compile(l->string, MCS_NOFLAGS, TRUE);
283 /*************************************************
284 * Setup entry point *
285 *************************************************/
287 /* This function is called when the transport is about to be used,
288 but before running it in a sub-process. It is used for two things:
290 (1) To set the fallback host list in addresses, when delivering.
291 (2) To pass back the interface, port, protocol, and other options, for use
292 during callout verification.
295 tblock pointer to the transport instance block
296 addrlist list of addresses about to be transported
297 tf if not NULL, pointer to block in which to return options
298 uid the uid that will be set (not used)
299 gid the gid that will be set (not used)
300 errmsg place for error message (not used)
302 Returns: OK always (FAIL, DEFER not used)
306 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
307 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
309 smtp_transport_options_block *ob = SOB tblock->options_block;
311 /* Pass back options if required. This interface is getting very messy. */
315 tf->interface = ob->interface;
317 tf->protocol = ob->protocol;
318 tf->hosts = ob->hosts;
319 tf->hosts_override = ob->hosts_override;
320 tf->hosts_randomize = ob->hosts_randomize;
321 tf->gethostbyname = ob->gethostbyname;
322 tf->qualify_single = ob->dns_qualify_single;
323 tf->search_parents = ob->dns_search_parents;
324 tf->helo_data = ob->helo_data;
327 /* Set the fallback host list for all the addresses that don't have fallback
328 host lists, provided that the local host wasn't present in the original host
331 if (!testflag(addrlist, af_local_host_removed))
332 for (; addrlist; addrlist = addrlist->next)
333 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
340 /*************************************************
341 * Initialization entry point *
342 *************************************************/
344 /* Called for each instance, after its options have been read, to
345 enable consistency checks to be done, or anything else that needs
348 Argument: pointer to the transport instance block
353 smtp_transport_init(transport_instance *tblock)
355 smtp_transport_options_block *ob = SOB tblock->options_block;
356 int old_pool = store_pool;
358 /* Retry_use_local_part defaults FALSE if unset */
360 if (tblock->retry_use_local_part == TRUE_UNSET)
361 tblock->retry_use_local_part = FALSE;
363 /* Set the default port according to the protocol */
366 ob->port = strcmpic(ob->protocol, US"lmtp") == 0
368 : strcmpic(ob->protocol, US"smtps") == 0
369 ? US"smtps" : US"smtp";
371 /* Set up the setup entry point, to be called before subprocesses for this
374 tblock->setup = smtp_transport_setup;
376 /* Complain if any of the timeouts are zero. */
378 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
379 ob->final_timeout <= 0)
380 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
381 "command, data, or final timeout value is zero for %s transport",
384 /* If hosts_override is set and there are local hosts, set the global
385 flag that stops verify from showing router hosts. */
387 if (ob->hosts_override && ob->hosts) tblock->overrides_hosts = TRUE;
389 /* If there are any fallback hosts listed, build a chain of host items
390 for them, but do not do any lookups at this time. */
392 store_pool = POOL_PERM;
393 host_build_hostlist(&ob->fallback_hostlist, ob->fallback_hosts, FALSE);
394 store_pool = old_pool;
401 /*************************************************
402 * Set delivery info into all active addresses *
403 *************************************************/
405 /* Only addresses whose status is >= PENDING are relevant. A lesser
406 status means that an address is not currently being processed.
409 addrlist points to a chain of addresses
410 errno_value to put in each address's errno field
411 msg to put in each address's message field
412 rc to put in each address's transport_return field
413 pass_message if TRUE, set the "pass message" flag in the address
414 host if set, mark addrs as having used this host
415 smtp_greeting from peer
416 helo_response from peer
417 start points to timestamp of delivery start
419 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
420 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
421 this particular type of timeout.
427 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
428 BOOL pass_message, host_item * host,
429 #ifdef EXPERIMENTAL_DSN_INFO
430 const uschar * smtp_greeting, const uschar * helo_response,
432 struct timeval * start
436 struct timeval deliver_time;
438 if (errno_value == ERRNO_CONNECTTIMEOUT)
440 errno_value = ETIMEDOUT;
441 orvalue = RTEF_CTOUT;
443 timesince(&deliver_time, start);
445 for (address_item * addr = addrlist; addr; addr = addr->next)
446 if (addr->transport_return >= PENDING)
448 addr->basic_errno = errno_value;
449 addr->more_errno |= orvalue;
450 addr->delivery_time = deliver_time;
454 if (pass_message) setflag(addr, af_pass_message);
456 addr->transport_return = rc;
459 addr->host_used = host;
460 #ifdef EXPERIMENTAL_DSN_INFO
462 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
463 addr->smtp_greeting = smtp_greeting;
466 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
467 addr->helo_response = helo_response;
474 set_errno_nohost(address_item * addrlist, int errno_value, uschar * msg, int rc,
475 BOOL pass_message, struct timeval * start)
477 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL,
478 #ifdef EXPERIMENTAL_DSN_INFO
485 /*************************************************
486 * Check an SMTP response *
487 *************************************************/
489 /* This function is given an errno code and the SMTP response buffer
490 to analyse, together with the host identification for generating messages. It
491 sets an appropriate message and puts the first digit of the response code into
492 the yield variable. If no response was actually read, a suitable digit is
496 host the current host, to get its name for messages
497 errno_value pointer to the errno value
498 more_errno from the top address for use with ERRNO_FILTER_FAIL
499 buffer the SMTP response buffer
500 yield where to put a one-digit SMTP response code
501 message where to put an error message
502 pass_message set TRUE if message is an SMTP response
504 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
508 check_response(host_item *host, int *errno_value, int more_errno,
509 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
511 uschar * pl = pipelining_active ? US"pipelined " : US"";
514 *yield = '4'; /* Default setting is to give a temporary error */
518 case ETIMEDOUT: /* Handle response timeout */
519 *message = US string_sprintf("SMTP timeout after %s%s",
521 if (transport_count > 0)
522 *message = US string_sprintf("%s (%d bytes written)", *message,
526 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
527 s = string_printing(buffer);
528 while (isspace(*s)) s++;
530 ? string_sprintf("Malformed SMTP reply (an empty line) "
531 "in response to %s%s", pl, smtp_command)
532 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
533 pl, smtp_command, s);
536 case ERRNO_TLSFAILURE: /* Handle bad first read; can happen with
538 *message = US"bad first read from TLS conn";
541 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
542 can't send QUIT as we mustn't end the DATA. */
543 *message = string_sprintf("transport filter process failed (%d)%s",
545 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
548 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
549 can't send QUIT as we mustn't end the DATA. */
551 string_sprintf("failed to expand headers_add or headers_remove: %s",
552 expand_string_message);
555 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
556 *message = US"failed to write a data block";
560 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
561 *message = US"utf8 support required but not offered for forwarding";
562 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
567 /* Handle error responses from the remote mailer. */
571 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
572 "%s", pl, smtp_command, s = string_printing(buffer));
573 *pass_message = TRUE;
578 /* No data was read. If there is no errno, this must be the EOF (i.e.
579 connection closed) case, which causes deferral. An explicit connection reset
580 error has the same effect. Otherwise, put the host's identity in the message,
581 leaving the errno value to be interpreted as well. In all cases, we have to
582 assume the connection is now dead. */
584 if (*errno_value == 0 || *errno_value == ECONNRESET)
586 *errno_value = ERRNO_SMTPCLOSED;
587 *message = US string_sprintf("Remote host closed connection "
588 "in response to %s%s", pl, smtp_command);
591 *message = US string_sprintf("%s [%s]", host->name, host->address);
598 /*************************************************
599 * Write error message to logs *
600 *************************************************/
602 /* This writes to the main log and to the message log.
605 host the current host
606 detail the current message (addr_item->message)
607 basic_errno the errno (addr_item->basic_errno)
613 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
615 gstring * message = LOGGING(outgoing_port)
616 ? string_fmt_append(NULL, "H=%s [%s]:%d", host->name, host->address,
617 host->port == PORT_NONE ? 25 : host->port)
618 : string_fmt_append(NULL, "H=%s [%s]", host->name, host->address);
622 message = string_fmt_append(message, ": %s", suffix);
624 message = string_fmt_append(message, ": %s", strerror(basic_errno));
627 message = string_fmt_append(message, " %s", exim_errstr(basic_errno));
629 log_write(0, LOG_MAIN, "%s", string_from_gstring(message));
630 deliver_msglog("%s %s\n", tod_stamp(tod_log), message->s);
634 msglog_line(host_item * host, uschar * message)
636 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
637 host->name, host->address, message);
642 #ifndef DISABLE_EVENT
643 /*************************************************
644 * Post-defer action *
645 *************************************************/
647 /* This expands an arbitrary per-transport string.
648 It might, for example, be used to write to the database log.
651 addr the address item containing error information
652 host the current host
659 deferred_event_raise(address_item * addr, host_item * host, uschar * evstr)
661 uschar * action = addr->transport->event_action;
662 const uschar * save_domain;
668 save_domain = deliver_domain;
669 save_local = deliver_localpart;
671 /*XXX would ip & port already be set up? */
672 deliver_host_address = string_copy(host->address);
673 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
674 event_defer_errno = addr->basic_errno;
676 router_name = addr->router->name;
677 transport_name = addr->transport->name;
678 deliver_domain = addr->domain;
679 deliver_localpart = addr->local_part;
681 (void) event_raise(action, evstr,
683 ? addr->basic_errno > 0
684 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
685 : string_copy(addr->message)
686 : addr->basic_errno > 0
687 ? string_copy(US strerror(addr->basic_errno))
691 deliver_localpart = save_local;
692 deliver_domain = save_domain;
693 router_name = transport_name = NULL;
697 /*************************************************
698 * Reap SMTP specific responses *
699 *************************************************/
701 smtp_discard_responses(smtp_context * sx, smtp_transport_options_block * ob,
704 uschar flushbuffer[4096];
708 if (!smtp_read_response(sx, flushbuffer, sizeof(flushbuffer),
709 '2', ob->command_timeout)
710 && (errno != 0 || flushbuffer[0] == 0))
717 /* Return boolean success */
720 smtp_reap_banner(smtp_context * sx)
723 #if defined(__linux__) && defined(TCP_QUICKACK)
724 { /* Hack to get QUICKACK disabled; has to be right after 3whs, and has to on->off */
725 int sock = sx->cctx.sock;
726 struct pollfd p = {.fd = sock, .events = POLLOUT};
727 if (poll(&p, 1, 1000) >= 0) /* retval test solely for compiler quitening */
729 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &on, sizeof(on));
730 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
734 good_response = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
735 '2', (SOB sx->conn_args.ob)->command_timeout);
736 #ifdef EXPERIMENTAL_DSN_INFO
737 sx->smtp_greeting = string_copy(sx->buffer);
739 return good_response;
743 smtp_reap_ehlo(smtp_context * sx)
745 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
746 (SOB sx->conn_args.ob)->command_timeout))
748 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
750 #ifdef EXPERIMENTAL_DSN_INFO
751 sx->helo_response = string_copy(sx->buffer);
757 #ifdef EXPERIMENTAL_DSN_INFO
758 sx->helo_response = string_copy(sx->buffer);
760 #ifndef DISABLE_EVENT
761 (void) event_raise(sx->conn_args.tblock->event_action,
762 US"smtp:ehlo", sx->buffer, NULL);
768 /* Grab a string differentiating server behind a loadbalancer, for TLS
769 resumption when such servers do not share a session-cache */
772 ehlo_response_lbserver(smtp_context * sx, smtp_transport_options_block * ob)
774 #if !defined(DISABLE_TLS) && !defined(DISABLE_TLS_RESUME)
776 uschar * save_item = iterate_item;
778 if (sx->conn_args.have_lbserver)
780 iterate_item = sx->buffer;
781 s = expand_cstring(ob->host_name_extract);
782 iterate_item = save_item;
783 sx->conn_args.host_lbserver = s && !*s ? NULL : s;
784 sx->conn_args.have_lbserver = TRUE;
790 /******************************************************************************/
792 #ifdef EXPERIMENTAL_ESMTP_LIMITS
793 /* If TLS, or TLS not offered, called with the EHLO response in the buffer.
794 Check it for a LIMITS keyword and parse values into the smtp context structure.
796 We don't bother with peers that we won't talk TLS to, even though they can,
797 just ignore their LIMITS advice (if any) and treat them as if they do not.
798 This saves us dealing with a duplicate set of values. */
801 ehlo_response_limits_read(smtp_context * sx)
805 /* matches up to just after the first space after the keyword */
807 if (regex_match(regex_LIMITS, sx->buffer, -1, &match))
808 for (const uschar * s = sx->buffer + Ustrlen(match); *s; )
810 while (isspace(*s)) s++;
811 if (*s == '\n') break;
813 if (strncmpic(s, US"MAILMAX=", 8) == 0)
815 sx->peer_limit_mail = atoi(CS (s += 8));
816 while (isdigit(*s)) s++;
818 else if (strncmpic(s, US"RCPTMAX=", 8) == 0)
820 sx->peer_limit_rcpt = atoi(CS (s += 8));
821 while (isdigit(*s)) s++;
823 else if (strncmpic(s, US"RCPTDOMAINMAX=", 14) == 0)
825 sx->peer_limit_rcptdom = atoi(CS (s += 14));
826 while (isdigit(*s)) s++;
829 while (*s && !isspace(*s)) s++;
833 /* Apply given values to the current connection */
835 ehlo_limits_apply(smtp_context * sx,
836 unsigned limit_mail, unsigned limit_rcpt, unsigned limit_rcptdom)
838 if (limit_mail && limit_mail < sx->max_mail) sx->max_mail = limit_mail;
839 if (limit_rcpt && limit_rcpt < sx->max_rcpt) sx->max_rcpt = limit_rcpt;
842 DEBUG(D_transport) debug_printf("will treat as !multi_domain\n");
843 sx->single_rcpt_domain = TRUE;
847 /* Apply values from EHLO-resp to the current connection */
849 ehlo_response_limits_apply(smtp_context * sx)
851 ehlo_limits_apply(sx, sx->peer_limit_mail, sx->peer_limit_rcpt,
852 sx->peer_limit_rcptdom);
855 /* Apply values read from cache to the current connection */
857 ehlo_cache_limits_apply(smtp_context * sx)
859 # ifndef DISABLE_PIPE_CONNECT
860 ehlo_limits_apply(sx, sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
861 sx->ehlo_resp.limit_rcptdom);
864 #endif /*EXPERIMENTAL_ESMTP_LIMITS*/
866 /******************************************************************************/
868 #ifndef DISABLE_PIPE_CONNECT
870 ehlo_cache_key(const smtp_context * sx)
872 host_item * host = sx->conn_args.host;
873 return Ustrchr(host->address, ':')
874 ? string_sprintf("[%s]:%d.EHLO", host->address,
875 host->port == PORT_NONE ? sx->port : host->port)
876 : string_sprintf("%s:%d.EHLO", host->address,
877 host->port == PORT_NONE ? sx->port : host->port);
880 /* Cache EHLO-response info for use by early-pipe.
882 - During a normal flow on EHLO response (either cleartext or under TLS),
883 when we are willing to do PIPECONNECT and it is offered
884 - During an early-pipe flow on receiving the actual EHLO response and noting
885 disparity versus the cached info used, when PIPECONNECT is still being offered
887 We assume that suitable values have been set in the sx.ehlo_resp structure for
888 features and auths; we handle the copy of limits. */
891 write_ehlo_cache_entry(smtp_context * sx)
893 open_db dbblock, * dbm_file;
895 # ifdef EXPERIMENTAL_ESMTP_LIMITS
896 sx->ehlo_resp.limit_mail = sx->peer_limit_mail;
897 sx->ehlo_resp.limit_rcpt = sx->peer_limit_rcpt;
898 sx->ehlo_resp.limit_rcptdom = sx->peer_limit_rcptdom;
901 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
903 uschar * ehlo_resp_key = ehlo_cache_key(sx);
904 dbdata_ehlo_resp er = { .data = sx->ehlo_resp };
907 # ifdef EXPERIMENTAL_ESMTP_LIMITS
908 if (sx->ehlo_resp.limit_mail || sx->ehlo_resp.limit_rcpt || sx->ehlo_resp.limit_rcptdom)
909 debug_printf("writing clr %04x/%04x cry %04x/%04x lim %05d/%05d/%05d\n",
910 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
911 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths,
912 sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
913 sx->ehlo_resp.limit_rcptdom);
916 debug_printf("writing clr %04x/%04x cry %04x/%04x\n",
917 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
918 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths);
920 dbfn_write(dbm_file, ehlo_resp_key, &er, (int)sizeof(er));
921 dbfn_close(dbm_file);
926 invalidate_ehlo_cache_entry(smtp_context * sx)
928 open_db dbblock, * dbm_file;
930 if ( sx->early_pipe_active
931 && (dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
933 uschar * ehlo_resp_key = ehlo_cache_key(sx);
934 dbfn_delete(dbm_file, ehlo_resp_key);
935 dbfn_close(dbm_file);
940 read_ehlo_cache_entry(smtp_context * sx)
945 if (!(dbm_file = dbfn_open(US"misc", O_RDONLY, &dbblock, FALSE, TRUE)))
946 { DEBUG(D_transport) debug_printf("ehlo-cache: no misc DB\n"); }
949 uschar * ehlo_resp_key = ehlo_cache_key(sx);
950 dbdata_ehlo_resp * er;
952 if (!(er = dbfn_read_enforce_length(dbm_file, ehlo_resp_key, sizeof(dbdata_ehlo_resp))))
953 { DEBUG(D_transport) debug_printf("no ehlo-resp record\n"); }
954 else if (time(NULL) - er->time_stamp > retry_data_expire)
956 DEBUG(D_transport) debug_printf("ehlo-resp record too old\n");
957 dbfn_close(dbm_file);
958 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
959 dbfn_delete(dbm_file, ehlo_resp_key);
964 # ifdef EXPERIMENTAL_ESMTP_LIMITS
965 if (er->data.limit_mail || er->data.limit_rcpt || er->data.limit_rcptdom)
966 debug_printf("EHLO response bits from cache:"
967 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x lim %05d/%05d/%05d\n",
968 er->data.cleartext_features, er->data.cleartext_auths,
969 er->data.crypted_features, er->data.crypted_auths,
970 er->data.limit_mail, er->data.limit_rcpt, er->data.limit_rcptdom);
973 debug_printf("EHLO response bits from cache:"
974 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x\n",
975 er->data.cleartext_features, er->data.cleartext_auths,
976 er->data.crypted_features, er->data.crypted_auths);
978 sx->ehlo_resp = er->data;
979 # ifdef EXPERIMENTAL_ESMTP_LIMITS
980 ehlo_cache_limits_apply(sx);
982 dbfn_close(dbm_file);
985 dbfn_close(dbm_file);
992 /* Return an auths bitmap for the set of AUTH methods offered by the server
993 which match our client-side authenticators. */
995 static unsigned short
996 study_ehlo_auths(smtp_context * sx)
1001 unsigned short authbits = 0;
1003 if (!sx->esmtp) return 0;
1004 if (!regex_AUTH) regex_AUTH = regex_must_compile(AUTHS_REGEX, MCS_NOFLAGS, TRUE);
1005 if (!regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)) return 0;
1006 expand_nmax = -1; /* reset */
1007 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1009 for (au = auths, authnum = 0; au; au = au->next, authnum++) if (au->client)
1011 const uschar * list = names;
1013 for (int sep = ' '; s = string_nextinlist(&list, &sep, NULL, 0); )
1014 if (strcmpic(au->public_name, s) == 0)
1015 { authbits |= BIT(authnum); break; }
1019 debug_printf("server offers %s AUTH, methods '%s', usable-bitmap 0x%04x\n",
1020 tls_out.active.sock >= 0 ? "crypted" : "plaintext", names, authbits);
1022 if (tls_out.active.sock >= 0)
1023 sx->ehlo_resp.crypted_auths = authbits;
1025 sx->ehlo_resp.cleartext_auths = authbits;
1032 /* Wait for and check responses for early-pipelining.
1034 Called from the lower-level smtp_read_response() function
1035 used for general code that assume synchronisation, if context
1036 flags indicate outstanding early-pipelining commands. Also
1037 called fom sync_responses() which handles pipelined commands.
1040 sx smtp connection context
1041 countp number of outstanding responses, adjusted on return
1045 DEFER error on first read of TLS'd conn
1046 FAIL SMTP error in response
1049 smtp_reap_early_pipe(smtp_context * sx, int * countp)
1051 BOOL pending_BANNER = sx->pending_BANNER;
1052 BOOL pending_EHLO = sx->pending_EHLO;
1055 sx->pending_BANNER = FALSE; /* clear early to avoid recursion */
1056 sx->pending_EHLO = FALSE;
1060 DEBUG(D_transport) debug_printf("%s expect banner\n", __FUNCTION__);
1062 if (!smtp_reap_banner(sx))
1064 DEBUG(D_transport) debug_printf("bad banner\n");
1065 if (tls_out.active.sock >= 0) rc = DEFER;
1068 /*XXX EXPERIMENTAL_ESMTP_LIMITS ? */
1069 ehlo_response_lbserver(sx, sx->conn_args.ob);
1074 unsigned peer_offered;
1075 unsigned short authbits = 0, * ap;
1077 DEBUG(D_transport) debug_printf("%s expect ehlo\n", __FUNCTION__);
1079 if (!smtp_reap_ehlo(sx))
1081 DEBUG(D_transport) debug_printf("bad response for EHLO\n");
1082 if (tls_out.active.sock >= 0) rc = DEFER;
1086 /* Compare the actual EHLO response extensions and AUTH methods to the cached
1087 value we assumed; on difference, dump or rewrite the cache and arrange for a
1090 ap = tls_out.active.sock < 0
1091 ? &sx->ehlo_resp.cleartext_auths : &sx->ehlo_resp.crypted_auths;
1093 peer_offered = ehlo_response(sx->buffer,
1094 (tls_out.active.sock < 0 ? OPTION_TLS : 0)
1095 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
1096 | OPTION_UTF8 | OPTION_EARLY_PIPE
1098 # ifdef EXPERIMENTAL_ESMTP_LIMITS
1099 if (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1100 ehlo_response_limits_read(sx);
1102 if ( peer_offered != sx->peer_offered
1103 || (authbits = study_ehlo_auths(sx)) != *ap)
1106 debug_printf("EHLO %s extensions changed, 0x%04x/0x%04x -> 0x%04x/0x%04x\n",
1107 tls_out.active.sock < 0 ? "cleartext" : "crypted",
1108 sx->peer_offered, *ap, peer_offered, authbits);
1109 if (peer_offered & OPTION_EARLY_PIPE)
1111 *(tls_out.active.sock < 0
1112 ? &sx->ehlo_resp.cleartext_features : &sx->ehlo_resp.crypted_features) =
1115 write_ehlo_cache_entry(sx);
1119 invalidate_ehlo_cache_entry(sx);
1120 sx->early_pipe_active = FALSE; /* cancel further early-pipe on this conn */
1123 return OK; /* just carry on */
1125 # ifdef EXPERIMENTAL_ESMTP_LIMITS
1126 /* If we are handling LIMITS, compare the actual EHLO LIMITS values with the
1127 cached values and invalidate cache if different. OK to carry on with
1128 connect since values are advisory. */
1130 if ( (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1131 && ( sx->peer_limit_mail != sx->ehlo_resp.limit_mail
1132 || sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt
1133 || sx->peer_limit_rcptdom != sx->ehlo_resp.limit_rcptdom
1138 debug_printf("EHLO LIMITS changed:");
1139 if (sx->peer_limit_mail != sx->ehlo_resp.limit_mail)
1140 debug_printf(" MAILMAX %u -> %u\n", sx->ehlo_resp.limit_mail, sx->peer_limit_mail);
1141 else if (sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt)
1142 debug_printf(" RCPTMAX %u -> %u\n", sx->ehlo_resp.limit_rcpt, sx->peer_limit_rcpt);
1144 debug_printf(" RCPTDOMAINMAX %u -> %u\n", sx->ehlo_resp.limit_rcptdom, sx->peer_limit_rcptdom);
1146 invalidate_ehlo_cache_entry(sx);
1154 invalidate_ehlo_cache_entry(sx);
1155 (void) smtp_discard_responses(sx, sx->conn_args.ob, *countp);
1158 #endif /*!DISABLE_PIPE_CONNECT*/
1161 /*************************************************
1162 * Synchronize SMTP responses *
1163 *************************************************/
1165 /* This function is called from smtp_deliver() to receive SMTP responses from
1166 the server, and match them up with the commands to which they relate. When
1167 PIPELINING is not in use, this function is called after every command, and is
1168 therefore somewhat over-engineered, but it is simpler to use a single scheme
1169 that works both with and without PIPELINING instead of having two separate sets
1172 The set of commands that are buffered up with pipelining may start with MAIL
1173 and may end with DATA; in between are RCPT commands that correspond to the
1174 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
1175 etc.) are never buffered.
1177 Errors after MAIL or DATA abort the whole process leaving the response in the
1178 buffer. After MAIL, pending responses are flushed, and the original command is
1179 re-instated in big_buffer for error messages. For RCPT commands, the remote is
1180 permitted to reject some recipient addresses while accepting others. However
1181 certain errors clearly abort the whole process. Set the value in
1182 transport_return to PENDING_OK if the address is accepted. If there is a
1183 subsequent general error, it will get reset accordingly. If not, it will get
1184 converted to OK at the end.
1187 sx smtp connection context
1188 count the number of responses to read
1189 pending_DATA 0 if last command sent was not DATA
1190 +1 if previously had a good recipient
1191 -1 if not previously had a good recipient
1193 Returns: 3 if at least one address had 2xx and one had 5xx
1194 2 if at least one address had 5xx but none had 2xx
1195 1 if at least one host had a 2xx response, but none had 5xx
1196 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
1197 -1 timeout while reading RCPT response
1198 -2 I/O or other non-response error for RCPT
1199 -3 DATA or MAIL failed - errno and buffer set
1200 -4 banner or EHLO failed (early-pipelining)
1201 -5 banner or EHLO failed (early-pipelining, TLS)
1205 sync_responses(smtp_context * sx, int count, int pending_DATA)
1207 address_item * addr = sx->sync_addr;
1208 smtp_transport_options_block * ob = sx->conn_args.ob;
1211 #ifndef DISABLE_PIPE_CONNECT
1213 if ((rc = smtp_reap_early_pipe(sx, &count)) != OK)
1214 return rc == FAIL ? -4 : -5;
1217 /* Handle the response for a MAIL command. On error, reinstate the original
1218 command in big_buffer for error message use, and flush any further pending
1219 responses before returning, except after I/O errors and timeouts. */
1221 if (sx->pending_MAIL)
1223 DEBUG(D_transport) debug_printf("%s expect mail\n", __FUNCTION__);
1225 sx->pending_MAIL = sx->RCPT_452 = FALSE;
1226 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1227 '2', ob->command_timeout))
1229 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
1230 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
1231 if (errno == ERRNO_TLSFAILURE)
1233 if (errno == 0 && sx->buffer[0] != 0)
1236 if (sx->buffer[0] == '4')
1238 save_errno = ERRNO_MAIL4XX;
1239 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1241 count = smtp_discard_responses(sx, ob, count);
1245 if (pending_DATA) count--; /* Number of RCPT responses to come */
1246 while (count-- > 0) /* Mark any pending addrs with the host used */
1248 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
1249 addr->host_used = sx->conn_args.host;
1256 if (pending_DATA) count--; /* Number of RCPT responses to come */
1258 /* Read and handle the required number of RCPT responses, matching each one up
1259 with an address by scanning for the next address whose status is PENDING_DEFER.
1264 while (addr->transport_return != PENDING_DEFER)
1265 if (!(addr = addr->next))
1268 /* The address was accepted */
1269 addr->host_used = sx->conn_args.host;
1271 DEBUG(D_transport) debug_printf("%s expect rcpt for %s\n", __FUNCTION__, addr->address);
1272 if (smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1273 '2', ob->command_timeout))
1276 addr->transport_return = PENDING_OK;
1278 /* If af_dr_retry_exists is set, there was a routing delay on this address;
1279 ensure that any address-specific retry record is expunged. We do this both
1280 for the basic key and for the version that also includes the sender. */
1282 if (testflag(addr, af_dr_retry_exists))
1284 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
1286 retry_add_item(addr, altkey, rf_delete);
1287 retry_add_item(addr, addr->address_retry_key, rf_delete);
1291 /* Error on first TLS read */
1293 else if (errno == ERRNO_TLSFAILURE)
1296 /* Timeout while reading the response */
1298 else if (errno == ETIMEDOUT)
1300 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
1301 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1302 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE, &sx->delivery_start);
1303 retry_add_item(addr, addr->address_retry_key, 0);
1304 update_waiting = FALSE;
1308 /* Handle other errors in obtaining an SMTP response by returning -1. This
1309 will cause all the addresses to be deferred. Restore the SMTP command in
1310 big_buffer for which we are checking the response, so the error message
1313 else if (errno != 0 || sx->buffer[0] == 0)
1315 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer }, * g = &gs;
1317 /* Use taint-unchecked routines for writing into big_buffer, trusting
1318 that we'll never expand it. */
1320 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, "RCPT TO:<%s>",
1321 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1322 string_from_gstring(g);
1326 /* Handle SMTP permanent and temporary response codes. */
1331 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
1332 "%s", transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes),
1333 string_printing(sx->buffer));
1334 setflag(addr, af_pass_message);
1336 msglog_line(sx->conn_args.host, addr->message);
1338 /* The response was 5xx */
1340 if (sx->buffer[0] == '5')
1342 addr->transport_return = FAIL;
1346 /* The response was 4xx */
1350 addr->transport_return = DEFER;
1351 addr->basic_errno = ERRNO_RCPT4XX;
1352 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1356 #ifndef DISABLE_EVENT
1357 event_defer_errno = addr->more_errno;
1358 msg_event_raise(US"msg:rcpt:host:defer", addr);
1360 /* If a 452 and we've had at least one 2xx or 5xx, set next_addr to the
1361 start point for another MAIL command. */
1363 if (addr->more_errno >> 8 == 52 && yield & 3)
1365 if (!sx->RCPT_452) /* initialised at MAIL-ack above */
1368 debug_printf("%s: seen first 452 too-many-rcpts\n", __FUNCTION__);
1369 sx->RCPT_452 = TRUE;
1370 sx->next_addr = addr;
1372 addr->transport_return = PENDING_DEFER;
1373 addr->basic_errno = 0;
1377 /* Log temporary errors if there are more hosts to be tried.
1378 If not, log this last one in the == line. */
1380 if (sx->conn_args.host->next)
1381 if (LOGGING(outgoing_port))
1382 log_write(0, LOG_MAIN, "H=%s [%s]:%d %s", sx->conn_args.host->name,
1383 sx->conn_args.host->address,
1384 sx->port == PORT_NONE ? 25 : sx->port, addr->message);
1386 log_write(0, LOG_MAIN, "H=%s [%s]: %s", sx->conn_args.host->name,
1387 sx->conn_args.host->address, addr->message);
1389 #ifndef DISABLE_EVENT
1391 msg_event_raise(US"msg:rcpt:defer", addr);
1394 /* Do not put this message on the list of those waiting for specific
1395 hosts, as otherwise it is likely to be tried too often. */
1397 update_waiting = FALSE;
1399 /* Add a retry item for the address so that it doesn't get tried again
1400 too soon. If address_retry_include_sender is true, add the sender address
1401 to the retry key. */
1403 retry_add_item(addr,
1404 ob->address_retry_include_sender
1405 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
1406 : addr->address_retry_key,
1412 if (count && !(addr = addr->next))
1414 } /* Loop for next RCPT response */
1416 /* Update where to start at for the next block of responses, unless we
1417 have already handled all the addresses. */
1419 if (addr) sx->sync_addr = addr->next;
1421 /* Handle a response to DATA. If we have not had any good recipients, either
1422 previously or in this block, the response is ignored. */
1424 if (pending_DATA != 0)
1426 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1427 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1428 '3', ob->command_timeout))
1434 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1437 if (pending_DATA > 0 || (yield & 1) != 0)
1439 if (errno == 0 && sx->buffer[0] == '4')
1441 errno = ERRNO_DATA4XX;
1442 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1446 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1447 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1448 "is in use and there were no good recipients\n", msg);
1452 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1453 present) received 3xx. If any RCPTs were handled and yielded anything other
1454 than 4xx, yield will be set non-zero. */
1463 /* Try an authenticator's client entry */
1466 try_authenticator(smtp_context * sx, auth_instance * au)
1468 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1469 host_item * host = sx->conn_args.host; /* host to deliver to */
1472 /* Set up globals for error messages */
1474 authenticator_name = au->name;
1475 driver_srcfile = au->srcfile;
1476 driver_srcline = au->srcline;
1478 sx->outblock.authenticating = TRUE;
1479 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1480 sx->buffer, sizeof(sx->buffer));
1481 sx->outblock.authenticating = FALSE;
1482 driver_srcfile = authenticator_name = NULL; driver_srcline = 0;
1483 DEBUG(D_transport) debug_printf("%s authenticator yielded %s\n", au->name, rc_names[rc]);
1485 /* A temporary authentication failure must hold up delivery to
1486 this host. After a permanent authentication failure, we carry on
1487 to try other authentication methods. If all fail hard, try to
1488 deliver the message unauthenticated unless require_auth was set. */
1493 f.smtp_authenticated = TRUE; /* stops the outer loop */
1494 client_authenticator = au->name;
1495 if (au->set_client_id)
1496 client_authenticated_id = expand_string(au->set_client_id);
1499 /* Failure after writing a command */
1504 /* Failure after reading a response */
1508 uschar * logmsg = NULL;
1510 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1511 #ifndef DISABLE_EVENT
1513 uschar * save_name = sender_host_authenticated;
1514 sender_host_authenticated = au->name;
1515 if ((logmsg = event_raise(sx->conn_args.tblock->event_action, US"auth:fail",
1517 log_write(0, LOG_MAIN, "%s", logmsg);
1518 sender_host_authenticated = save_name;
1522 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1523 au->name, host->name, host->address, sx->buffer);
1527 /* Failure by some other means. In effect, the authenticator
1528 decided it wasn't prepared to handle this case. Typically this
1529 is the result of "fail" in an expansion string. Do we need to
1530 log anything here? Feb 2006: a message is now put in the buffer
1531 if logging is required. */
1534 if (*sx->buffer != 0)
1535 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1536 "authentication H=%s [%s] %s", au->name, host->name,
1537 host->address, sx->buffer);
1540 /* Internal problem, message in buffer. */
1543 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1544 DEFER, FALSE, &sx->delivery_start);
1553 /* Do the client side of smtp-level authentication.
1556 sx smtp connection context
1558 sx->buffer should have the EHLO response from server (gets overwritten)
1561 OK Success, or failed (but not required): global "smtp_authenticated" set
1562 DEFER Failed authentication (and was required)
1563 ERROR Internal problem
1565 FAIL_SEND Failed communications - transmit
1570 smtp_auth(smtp_context * sx)
1572 host_item * host = sx->conn_args.host; /* host to deliver to */
1573 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1574 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1575 #ifndef DISABLE_PIPE_CONNECT
1576 unsigned short authbits = tls_out.active.sock >= 0
1577 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1579 uschar * fail_reason = US"server did not advertise AUTH support";
1581 f.smtp_authenticated = FALSE;
1582 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1585 regex_AUTH = regex_must_compile(AUTHS_REGEX, MCS_NOFLAGS, TRUE);
1587 /* Is the server offering AUTH? */
1591 #ifndef DISABLE_PIPE_CONNECT
1592 sx->early_pipe_active ? authbits
1595 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1598 uschar * names = NULL;
1599 expand_nmax = -1; /* reset */
1601 #ifndef DISABLE_PIPE_CONNECT
1602 if (!sx->early_pipe_active)
1604 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1606 /* Must not do this check until after we have saved the result of the
1607 regex match above as the check could be another RE. */
1609 if ( require_auth == OK
1610 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1612 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1613 fail_reason = US"no common mechanisms were found";
1615 #ifndef DISABLE_PIPE_CONNECT
1616 if (sx->early_pipe_active)
1618 /* Scan our authenticators (which support use by a client and were offered
1619 by the server (checked at cache-write time)), not suppressed by
1620 client_condition. If one is found, attempt to authenticate by calling its
1621 client function. We are limited to supporting up to 16 authenticator
1622 public-names by the number of bits in a short. */
1628 for (bitnum = 0, au = auths;
1629 !f.smtp_authenticated && au && bitnum < 16;
1630 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1632 if ( au->client_condition
1633 && !expand_check_condition(au->client_condition, au->name,
1634 US"client authenticator"))
1636 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1637 au->name, "client_condition is false");
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)
1654 /* Scan the configured authenticators looking for one which is configured
1655 for use as a client, which is not suppressed by client_condition, and
1656 whose name matches an authentication mechanism supported by the server.
1657 If one is found, attempt to authenticate by calling its client function.
1660 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1665 || ( au->client_condition
1666 && !expand_check_condition(au->client_condition, au->name,
1667 US"client authenticator")))
1669 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1671 (au->client)? "client_condition is false" :
1672 "not configured as a client");
1676 /* Loop to scan supported server mechanisms */
1680 int len = Ustrlen(au->public_name);
1683 while (isspace(*p)) p++;
1685 if (strncmpic(au->public_name, p, len) != 0 ||
1686 (p[len] != 0 && !isspace(p[len])))
1688 while (*p != 0 && !isspace(*p)) p++;
1692 /* Found data for a listed mechanism. Call its client entry. Set
1693 a flag in the outblock so that data is overwritten after sending so
1694 that reflections don't show it. */
1696 fail_reason = US"authentication attempt(s) failed";
1698 if ((rc = try_authenticator(sx, au)) != OK)
1701 break; /* If not authenticated, try next authenticator */
1702 } /* Loop for scanning supported server mechanisms */
1703 } /* Loop for further authenticators */
1707 /* If we haven't authenticated, but are required to, give up. */
1709 if (require_auth == OK && !f.smtp_authenticated)
1711 #ifndef DISABLE_PIPE_CONNECT
1712 invalidate_ehlo_cache_entry(sx);
1714 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1715 string_sprintf("authentication required but %s", fail_reason), DEFER,
1716 FALSE, &sx->delivery_start);
1724 /* Construct AUTH appendix string for MAIL TO */
1727 sx context for smtp connection
1728 p point in sx->buffer to build string
1729 addrlist chain of potential addresses to deliver
1731 Globals f.smtp_authenticated
1732 client_authenticated_sender
1733 Return True on error, otherwise buffer has (possibly empty) terminated string
1737 smtp_mail_auth_str(smtp_context * sx, uschar * p, address_item * addrlist)
1739 smtp_transport_options_block * ob = sx->conn_args.ob;
1740 uschar * local_authenticated_sender = authenticated_sender;
1743 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n",
1744 authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1747 if (ob->authenticated_sender)
1749 uschar * new = expand_string(ob->authenticated_sender);
1752 if (!f.expand_string_forcedfail)
1754 uschar *message = string_sprintf("failed to expand "
1755 "authenticated_sender: %s", expand_string_message);
1756 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
1761 local_authenticated_sender = new;
1764 /* Add the authenticated sender address if present */
1766 if ( (f.smtp_authenticated || ob->authenticated_sender_force)
1767 && local_authenticated_sender)
1769 string_format_nt(p, sizeof(sx->buffer) - (p-sx->buffer), " AUTH=%s",
1770 auth_xtextencode(local_authenticated_sender,
1771 Ustrlen(local_authenticated_sender)));
1772 client_authenticated_sender = string_copy(local_authenticated_sender);
1782 typedef struct smtp_compare_s
1784 uschar * current_sender_address;
1785 struct transport_instance * tblock;
1789 /* Create a unique string that identifies this message, it is based on
1790 sender_address, helo_data and tls_certificate if enabled.
1794 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1796 address_item * addr1;
1797 uschar * if1 = US"";
1798 uschar * helo1 = US"";
1800 uschar * tlsc1 = US"";
1802 uschar * save_sender_address = sender_address;
1803 uschar * local_identity = NULL;
1804 smtp_transport_options_block * ob = SOB tblock->options_block;
1806 sender_address = sender;
1808 addr1 = deliver_make_addr (sender, TRUE);
1809 deliver_set_expansions(addr1);
1812 if1 = expand_string(ob->interface);
1815 helo1 = expand_string(ob->helo_data);
1818 if (ob->tls_certificate)
1819 tlsc1 = expand_string(ob->tls_certificate);
1820 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1822 local_identity = string_sprintf ("%s^%s", if1, helo1);
1825 deliver_set_expansions(NULL);
1826 sender_address = save_sender_address;
1828 return local_identity;
1833 /* This routine is a callback that is called from transport_check_waiting.
1834 This function will evaluate the incoming message versus the previous
1835 message. If the incoming message is using a different local identity then
1836 we will veto this new message. */
1839 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1841 uschar * message_local_identity,
1842 * current_local_identity,
1843 * new_sender_address;
1845 current_local_identity =
1846 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1848 if (!(new_sender_address = spool_sender_from_msgid(message_id)))
1852 message_local_identity =
1853 smtp_local_identity(new_sender_address, s_compare->tblock);
1855 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1861 ehlo_response(uschar * buf, unsigned checks)
1863 PCRE2_SIZE bsize = Ustrlen(buf);
1864 pcre2_match_data * md = pcre2_match_data_create(1, pcre_gen_ctx);
1866 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1869 if ( checks & OPTION_TLS
1870 && pcre2_match(regex_STARTTLS,
1871 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1873 checks &= ~OPTION_TLS;
1875 if ( checks & OPTION_IGNQ
1876 && pcre2_match(regex_IGNOREQUOTA,
1877 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1878 checks &= ~OPTION_IGNQ;
1880 if ( checks & OPTION_CHUNKING
1881 && pcre2_match(regex_CHUNKING,
1882 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1883 checks &= ~OPTION_CHUNKING;
1885 #ifndef DISABLE_PRDR
1886 if ( checks & OPTION_PRDR
1887 && pcre2_match(regex_PRDR,
1888 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1890 checks &= ~OPTION_PRDR;
1893 if ( checks & OPTION_UTF8
1894 && pcre2_match(regex_UTF8,
1895 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1897 checks &= ~OPTION_UTF8;
1899 if ( checks & OPTION_DSN
1900 && pcre2_match(regex_DSN,
1901 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1902 checks &= ~OPTION_DSN;
1904 if ( checks & OPTION_PIPE
1905 && pcre2_match(regex_PIPELINING,
1906 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1907 checks &= ~OPTION_PIPE;
1909 if ( checks & OPTION_SIZE
1910 && pcre2_match(regex_SIZE,
1911 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1912 checks &= ~OPTION_SIZE;
1914 #ifndef DISABLE_PIPE_CONNECT
1915 if ( checks & OPTION_EARLY_PIPE
1916 && pcre2_match(regex_EARLY_PIPE,
1917 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1919 checks &= ~OPTION_EARLY_PIPE;
1921 /* pcre2_match_data_free(md); gen ctx needs no free */
1922 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1928 /* Callback for emitting a BDAT data chunk header.
1930 If given a nonzero size, first flush any buffered SMTP commands
1931 then emit the command.
1933 Reap previous SMTP command responses if requested, and always reap
1934 the response from a previous BDAT command.
1937 tctx transport context
1938 chunk_size value for SMTP BDAT command
1940 tc_chunk_last add LAST option to SMTP BDAT command
1941 tc_reap_prev reap response to previous SMTP commands
1945 DEFER TLS error on first read (EHLO-resp); errno set
1949 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1952 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1953 smtp_context * sx = tctx->smtp_context;
1957 /* Write SMTP chunk header command. If not reaping responses, note that
1958 there may be more writes (like, the chunk data) done soon. */
1962 #ifndef DISABLE_PIPE_CONNECT
1963 BOOL new_conn = !!(sx->outblock.conn_args);
1965 if((cmd_count = smtp_write_command(sx,
1966 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1967 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1968 ) < 0) return ERROR;
1969 if (flags & tc_chunk_last)
1970 data_command = string_copy(big_buffer); /* Save for later error message */
1971 #ifndef DISABLE_PIPE_CONNECT
1972 /* That command write could have been the one that made the connection.
1973 Copy the fd from the client conn ctx (smtp transport specific) to the
1974 generic transport ctx. */
1977 tctx->u.fd = sx->outblock.cctx->sock;
1981 prev_cmd_count = cmd_count += sx->cmd_count;
1983 /* Reap responses for any previous, but not one we just emitted */
1987 if (sx->pending_BDAT)
1990 if (flags & tc_reap_prev && prev_cmd_count > 0)
1992 DEBUG(D_transport) debug_printf("look for %d responses"
1993 " for previous pipelined cmds\n", prev_cmd_count);
1995 switch(sync_responses(sx, prev_cmd_count, 0))
1997 case 1: /* 2xx (only) => OK */
1998 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1999 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2000 case 0: break; /* No 2xx or 5xx, but no probs */
2002 case -5: errno = ERRNO_TLSFAILURE;
2004 #ifndef DISABLE_PIPE_CONNECT
2005 case -4: /* non-2xx for pipelined banner or EHLO */
2007 case -1: /* Timeout on RCPT */
2008 default: return ERROR; /* I/O error, or any MAIL/DATA error */
2011 if (!sx->pending_BDAT)
2012 pipelining_active = FALSE;
2015 /* Reap response for an outstanding BDAT */
2017 if (sx->pending_BDAT)
2019 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
2021 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
2022 ob->command_timeout))
2024 if (errno == 0 && sx->buffer[0] == '4')
2026 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
2027 sx->addrlist->more_errno |=
2028 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2033 sx->pending_BDAT = FALSE;
2034 pipelining_active = FALSE;
2036 else if (chunk_size > 0)
2037 sx->pending_BDAT = TRUE;
2040 sx->cmd_count = cmd_count;
2048 check_force_dane_conn(smtp_context * sx, smtp_transport_options_block * ob)
2051 if( sx->dane_required
2052 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2054 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2056 case OK: sx->conn_args.dane = TRUE;
2057 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2058 ob->tls_sni = sx->conn_args.host->name; /* force SNI */
2060 case FAIL_FORCED: break;
2061 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2062 string_sprintf("DANE error: tlsa lookup %s",
2064 rc, FALSE, &sx->delivery_start);
2065 # ifndef DISABLE_EVENT
2066 (void) event_raise(sx->conn_args.tblock->event_action,
2067 US"dane:fail", sx->dane_required
2068 ? US"dane-required" : US"dnssec-invalid",
2078 /*************************************************
2079 * Make connection for given message *
2080 *************************************************/
2084 sx connection context
2085 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2086 a second attempt after TLS initialization fails
2088 Returns: OK - the connection was made and the delivery attempted;
2089 fd is set in the conn context, tls_out set up.
2090 DEFER - the connection could not be made, or something failed
2091 while setting up the SMTP session, or there was a
2092 non-message-specific error, such as a timeout.
2093 ERROR - helo_data or add_headers or authenticated_sender is
2094 specified for this transport, and the string failed
2098 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
2100 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
2101 BOOL pass_message = FALSE;
2102 uschar * message = NULL;
2105 uschar * tls_errstr;
2108 /* Many lines of clearing individual elements of *sx that used to
2109 be here have been replaced by a full memset to zero (de41aff051).
2110 There are two callers, this file and verify.c . Now we only set
2111 up nonzero elements. */
2113 sx->conn_args.ob = ob;
2115 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
2116 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
2117 sx->send_rset = TRUE;
2118 sx->send_quit = TRUE;
2119 sx->setting_up = TRUE;
2121 sx->dsn_all_lasthop = TRUE;
2124 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
2127 if ((sx->max_mail = sx->conn_args.tblock->connection_max_messages) == 0)
2128 sx->max_mail = UNLIMITED_ADDRS;
2129 sx->max_rcpt = expand_max_rcpt(sx->conn_args.tblock->max_addresses);
2130 sx->igquotstr = US"";
2131 if (!sx->helo_data) sx->helo_data = ob->helo_data;
2133 smtp_command = US"initial connection";
2135 /* Set up the buffer for reading SMTP response packets. */
2137 sx->inblock.buffer = sx->inbuffer;
2138 sx->inblock.buffersize = sizeof(sx->inbuffer);
2139 sx->inblock.ptr = sx->inbuffer;
2140 sx->inblock.ptrend = sx->inbuffer;
2142 /* Set up the buffer for holding SMTP commands while pipelining */
2144 sx->outblock.buffer = sx->outbuffer;
2145 sx->outblock.buffersize = sizeof(sx->outbuffer);
2146 sx->outblock.ptr = sx->outbuffer;
2148 /* Reset the parameters of a TLS session. */
2151 tls_out.cipher = NULL; /* the one we may use for this transport */
2152 tls_out.ourcert = NULL;
2153 tls_out.peercert = NULL;
2154 tls_out.peerdn = NULL;
2158 tls_out.ocsp = OCSP_NOT_REQ;
2159 #ifndef DISABLE_TLS_RESUME
2160 tls_out.resumption = 0;
2164 /* Flip the legacy TLS-related variables over to the outbound set in case
2165 they're used in the context of the transport. Don't bother resetting
2166 afterward (when being used by a transport) as we're in a subprocess.
2167 For verify, unflipped once the callout is dealt with */
2169 tls_modify_variables(&tls_out);
2174 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
2175 DEFER, FALSE, &sx->delivery_start);
2180 /* If we have a proxied TLS connection, check usability for this message */
2182 if (continue_hostname && continue_proxy_cipher)
2185 const uschar * sni = US"";
2187 # ifdef SUPPORT_DANE
2188 /* Check if the message will be DANE-verified; if so force TLS and its SNI */
2190 tls_out.dane_verified = FALSE;
2191 smtp_port_for_connect(sx->conn_args.host, sx->port);
2192 if ( sx->conn_args.host->dnssec == DS_YES
2193 && (rc = check_force_dane_conn(sx, ob)) != OK
2198 /* If the SNI or the DANE status required for the new message differs from the
2199 existing conn drop the connection to force a new one. */
2201 if (ob->tls_sni && !(sni = expand_cstring(ob->tls_sni)))
2202 log_write(0, LOG_MAIN|LOG_PANIC,
2203 "<%s>: failed to expand transport's tls_sni value: %s",
2204 sx->addrlist->address, expand_string_message);
2206 # ifdef SUPPORT_DANE
2207 if ( (continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni)
2208 && continue_proxy_dane == sx->conn_args.dane)
2210 tls_out.sni = US sni;
2211 if ((tls_out.dane_verified = continue_proxy_dane))
2212 sx->conn_args.host->dnssec = DS_YES;
2215 if ((continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni))
2216 tls_out.sni = US sni;
2221 debug_printf("Closing proxied-TLS connection due to SNI mismatch\n");
2223 smtp_debug_cmd(US"QUIT", 0);
2224 write(0, "QUIT\r\n", 6);
2226 continue_hostname = continue_proxy_cipher = NULL;
2227 f.continue_more = FALSE;
2228 continue_sequence = 1; /* Unfortunately, this process cannot affect success log
2229 which is done by delivery proc. Would have to pass this
2230 back through reporting pipe. */
2233 #endif /*!DISABLE_TLS*/
2235 /* Make a connection to the host if this isn't a continued delivery, and handle
2236 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2237 specially so they can be identified for retries. */
2239 if (!continue_hostname)
2242 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2244 /* Arrange to report to calling process this is a new connection */
2246 clearflag(sx->first_addr, af_cont_conn);
2247 setflag(sx->first_addr, af_new_conn);
2249 /* Get the actual port the connection will use, into sx->conn_args.host */
2251 smtp_port_for_connect(sx->conn_args.host, sx->port);
2254 /* Do TLSA lookup for DANE */
2256 tls_out.dane_verified = FALSE;
2257 tls_out.tlsa_usage = 0;
2259 if (sx->conn_args.host->dnssec == DS_YES)
2262 if ((rc = check_force_dane_conn(sx, ob)) != OK)
2265 else if (sx->dane_required)
2267 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2268 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2269 FAIL, FALSE, &sx->delivery_start);
2270 # ifndef DISABLE_EVENT
2271 (void) event_raise(sx->conn_args.tblock->event_action,
2272 US"dane:fail", US"dane-required", NULL);
2279 /* Make the TCP connection */
2281 sx->cctx.tls_ctx = NULL;
2282 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2283 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2284 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom =
2286 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2287 #ifndef DISABLE_CLIENT_CMD_LOG
2288 client_cmd_log = NULL;
2291 #ifndef DISABLE_PIPE_CONNECT
2292 if ( verify_check_given_host(CUSS &ob->hosts_pipe_connect,
2293 sx->conn_args.host) == OK)
2295 /* We don't find out the local ip address until the connect, so if
2296 the helo string might use it avoid doing early-pipelining. */
2299 || sx->conn_args.interface
2300 || !Ustrstr(sx->helo_data, "$sending_ip_address")
2301 || Ustrstr(sx->helo_data, "def:sending_ip_address")
2304 sx->early_pipe_ok = TRUE;
2305 if ( read_ehlo_cache_entry(sx)
2306 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2309 debug_printf("Using cached cleartext PIPECONNECT\n");
2310 sx->early_pipe_active = TRUE;
2311 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2314 else DEBUG(D_transport)
2315 debug_printf("helo needs $sending_ip_address; avoid early-pipelining\n");
2318 if (sx->early_pipe_active)
2320 sx->outblock.conn_args = &sx->conn_args;
2321 (void) smtp_boundsock(&sx->conn_args);
2326 blob lazy_conn = {.data = NULL};
2327 /* For TLS-connect, a TFO lazy-connect is useful since the Client Hello
2328 can go on the TCP SYN. */
2330 if ((sx->cctx.sock = smtp_connect(&sx->conn_args,
2331 sx->smtps ? &lazy_conn : NULL)) < 0)
2333 set_errno_nohost(sx->addrlist,
2334 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2335 sx->verify ? US strerror(errno) : NULL,
2336 DEFER, FALSE, &sx->delivery_start);
2337 sx->send_quit = FALSE;
2341 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2345 /* Expand the greeting message while waiting for the initial response. (Makes
2346 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2347 delayed till here so that $sending_ip_address and $sending_port are set.
2348 Those will be known even for a TFO lazy-connect, having been set by the bind().
2349 For early-pipe, we are ok if binding to a local interface; otherwise (if
2350 $sending_ip_address is seen in helo_data) we disabled early-pipe above. */
2353 if (!(sx->helo_data = expand_string(sx->helo_data)))
2355 log_write(0, LOG_MAIN|LOG_PANIC,
2356 "<%s>: failed to expand transport's helo_data value for callout: %s",
2357 sx->addrlist->address, expand_string_message);
2362 expand_string_message = NULL;
2363 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2364 &expand_string_message)),
2365 expand_string_message)
2367 log_write(0, LOG_MAIN|LOG_PANIC,
2368 "<%s>: failed to expand transport's helo_data value for callout: %s",
2369 sx->addrlist->address, expand_string_message);
2371 sx->helo_data = NULL;
2375 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2376 is nevertheless a reasonably clean way of programming this kind of logic,
2377 where you want to escape on any error. */
2381 #ifndef DISABLE_PIPE_CONNECT
2382 if (sx->early_pipe_active)
2384 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2385 sx->outblock.cmd_count = 1;
2390 if (!smtp_reap_banner(sx))
2391 goto RESPONSE_FAILED;
2394 #ifndef DISABLE_EVENT
2397 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2398 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2399 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer, NULL);
2402 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2403 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2404 DEFER, FALSE, &sx->delivery_start);
2411 /* Now check if the helo_data expansion went well, and sign off cleanly if
2416 message = string_sprintf("failed to expand helo_data: %s",
2417 expand_string_message);
2418 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2424 /** Debugging without sending a message
2425 sx->addrlist->transport_return = DEFER;
2429 /* Errors that occur after this point follow an SMTP command, which is
2430 left in big_buffer by smtp_write_command() for use in error messages. */
2432 smtp_command = big_buffer;
2434 /* Tell the remote who we are...
2436 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2437 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2438 greeting is of this form. The assumption was that the far end supports it
2439 properly... but experience shows that there are some that give 5xx responses,
2440 even though the banner includes "ESMTP" (there's a bloody-minded one that
2441 says "ESMTP not spoken here"). Cope with that case.
2443 September 2000: Time has passed, and it seems reasonable now to always send
2444 EHLO at the start. It is also convenient to make the change while installing
2447 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2448 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2449 would be no way to send out the mails, so there is now a host list
2450 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2451 PIPELINING problem as well. Maybe it can also be useful to cure other
2452 problems with broken servers.
2454 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2455 Then somebody tried it with a Microsoft mailer... It seems that all other
2456 mailers use upper case for some reason (the RFC is quite clear about case
2457 independence) so, for peace of mind, I gave in. */
2459 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2461 /* Alas; be careful, since this goto is not an error-out, so conceivably
2462 we might set data between here and the target which we assume to exist
2463 and be usable. I can see this coming back to bite us. */
2467 smtp_peer_options |= OPTION_TLS;
2468 suppress_tls = FALSE;
2469 ob->tls_tempfail_tryclear = FALSE;
2470 smtp_command = US"SSL-on-connect";
2477 if (smtp_write_command(sx,
2478 #ifndef DISABLE_PIPE_CONNECT
2479 sx->early_pipe_active ? SCMD_BUFFER :
2482 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2484 sx->esmtp_sent = TRUE;
2486 #ifndef DISABLE_PIPE_CONNECT
2487 if (sx->early_pipe_active)
2489 sx->pending_EHLO = TRUE;
2491 /* If we have too many authenticators to handle and might need to AUTH
2492 for this transport, pipeline no further as we will need the
2493 list of auth methods offered. Reap the banner and EHLO. */
2495 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2496 && f.smtp_in_early_pipe_no_auth)
2498 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2499 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2501 if (sync_responses(sx, 2, 0) != 0)
2504 debug_printf("failed reaping pipelined cmd responses\n");
2505 goto RESPONSE_FAILED;
2507 sx->early_pipe_active = FALSE;
2512 if (!smtp_reap_ehlo(sx))
2513 goto RESPONSE_FAILED;
2517 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2519 #ifndef DISABLE_PIPE_CONNECT
2520 if (!sx->early_pipe_active)
2525 int n = sizeof(sx->buffer);
2526 uschar * rsp = sx->buffer;
2528 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer) + 1) < sizeof(sx->buffer)/2)
2529 { rsp = sx->buffer + n; n = sizeof(sx->buffer) - n; }
2531 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2533 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2534 #ifdef EXPERIMENTAL_DSN_INFO
2535 sx->helo_response = string_copy(rsp);
2539 /* Handle special logging for a closed connection after HELO
2540 when had previously sent EHLO */
2542 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2544 errno = ERRNO_SMTPCLOSED;
2545 goto EHLOHELO_FAILED;
2547 memmove(sx->buffer, rsp, Ustrlen(rsp));
2548 goto RESPONSE_FAILED;
2552 if (sx->esmtp || sx->lmtp)
2554 #ifndef DISABLE_PIPE_CONNECT
2555 if (!sx->early_pipe_active)
2558 sx->peer_offered = ehlo_response(sx->buffer,
2559 OPTION_TLS /* others checked later */
2560 #ifndef DISABLE_PIPE_CONNECT
2561 | (sx->early_pipe_ok
2563 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2572 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2573 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2575 ehlo_response_limits_read(sx);
2576 ehlo_response_limits_apply(sx);
2579 #ifndef DISABLE_PIPE_CONNECT
2580 if (sx->early_pipe_ok)
2582 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2584 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2585 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2587 DEBUG(D_transport) debug_printf("PIPECONNECT usable in future for this IP\n");
2588 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2589 write_ehlo_cache_entry(sx);
2593 ehlo_response_lbserver(sx, ob);
2596 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2599 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2604 /* For continuing deliveries down the same channel, having re-exec'd the socket
2605 is the standard input; for a socket held open from verify it is recorded
2606 in the cutthrough context block. Either way we don't need to redo EHLO here
2607 (but may need to do so for TLS - see below).
2608 Set up the pointer to where subsequent commands will be left, for
2609 error messages. Note that smtp_peer_options will have been
2610 set from the command line if they were set in the process that passed the
2613 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2614 as the continue goes via transport_pass_socket() and doublefork and exec.
2615 It does not wait. Unclear how we keep separate host's responses
2616 separate - we could match up by host ip+port as a bodge. */
2620 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2622 sx->cctx = cutthrough.cctx;
2623 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2627 sx->cctx.sock = 0; /* stdin */
2628 sx->cctx.tls_ctx = NULL;
2629 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2631 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2632 smtp_command = big_buffer;
2633 sx->peer_offered = smtp_peer_options;
2634 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2635 /* Limits passed by cmdline over exec. */
2636 ehlo_limits_apply(sx,
2637 sx->peer_limit_mail = continue_limit_mail,
2638 sx->peer_limit_rcpt = continue_limit_rcpt,
2639 sx->peer_limit_rcptdom = continue_limit_rcptdom);
2641 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2643 /* For a continued connection with TLS being proxied for us, or a
2644 held-open verify connection with TLS, nothing more to do. */
2646 if ( continue_proxy_cipher
2647 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2648 && cutthrough.is_tls)
2651 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2652 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2653 continue_proxy_cipher ? "proxied" : "verify conn with");
2656 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2659 /* If TLS is available on this connection, whether continued or not, attempt to
2660 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2661 send another EHLO - the server may give a different answer in secure mode. We
2662 use a separate buffer for reading the response to STARTTLS so that if it is
2663 negative, the original EHLO data is available for subsequent analysis, should
2664 the client not be required to use TLS. If the response is bad, copy the buffer
2665 for error analysis. */
2668 if ( smtp_peer_options & OPTION_TLS
2670 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2672 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2675 uschar buffer2[4096];
2677 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2680 #ifndef DISABLE_PIPE_CONNECT
2681 /* If doing early-pipelining reap the banner and EHLO-response but leave
2682 the response for the STARTTLS we just sent alone. On fail, assume wrong
2683 cached capability and retry with the pipelining disabled. */
2685 if (sx->early_pipe_active)
2687 if (sync_responses(sx, 2, 0) != 0)
2690 debug_printf("failed reaping pipelined cmd responses\n");
2691 close(sx->cctx.sock);
2693 sx->early_pipe_active = FALSE;
2694 goto PIPE_CONNECT_RETRY;
2699 /* If there is an I/O error, transmission of this message is deferred. If
2700 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2701 false, we also defer. However, if there is a temporary rejection of STARTTLS
2702 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2703 STARTTLS, we carry on. This means we will try to send the message in clear,
2704 unless the host is in hosts_require_tls (tested below). */
2706 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2710 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2713 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2714 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2715 goto RESPONSE_FAILED;
2719 /* STARTTLS accepted: try to negotiate a TLS session. */
2724 sx->conn_args.sending_ip_address = sending_ip_address;
2725 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2727 /* TLS negotiation failed; give an error. From outside, this function may
2728 be called again to try in clear on a new connection, if the options permit
2729 it for this host. */
2731 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2733 # ifdef SUPPORT_DANE
2734 if (sx->conn_args.dane)
2736 log_write(0, LOG_MAIN,
2737 "DANE attempt failed; TLS connection to %s [%s]: %s",
2738 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2739 # ifndef DISABLE_EVENT
2740 (void) event_raise(sx->conn_args.tblock->event_action,
2741 US"dane:fail", US"validation-failure", NULL); /* could do with better detail */
2746 errno = ERRNO_TLSFAILURE;
2747 message = string_sprintf("TLS session: %s", tls_errstr);
2748 sx->send_quit = FALSE;
2751 sx->send_tlsclose = TRUE;
2753 /* TLS session is set up. Check the inblock fill level. If there is
2754 content then as we have not yet done a tls read it must have arrived before
2755 the TLS handshake, in-clear. That violates the sync requirement of the
2756 STARTTLS RFC, so fail. */
2758 if (sx->inblock.ptr != sx->inblock.ptrend)
2762 int i = sx->inblock.ptrend - sx->inblock.ptr;
2763 debug_printf("unused data in input buffer after ack for STARTTLS:\n"
2765 i > 100 ? 100 : i, sx->inblock.ptr, i > 100 ? "..." : "");
2767 tls_errstr = US"synch error before connect";
2768 goto TLS_CONN_FAILED;
2771 smtp_peer_options_wrap = smtp_peer_options;
2772 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2773 if (addr->transport_return == PENDING_DEFER)
2775 addr->cipher = tls_out.cipher;
2776 addr->ourcert = tls_out.ourcert;
2777 addr->peercert = tls_out.peercert;
2778 addr->peerdn = tls_out.peerdn;
2779 addr->ocsp = tls_out.ocsp;
2780 addr->tlsver = tls_out.ver;
2785 /* if smtps, we'll have smtp_command set to something else; always safe to
2787 smtp_command = big_buffer;
2789 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2790 helo_data is null, we are dealing with a connection that was passed from
2791 another process, and so we won't have expanded helo_data above. We have to
2792 expand it here. $sending_ip_address and $sending_port are set up right at the
2793 start of the Exim process (in exim.c). */
2795 if (tls_out.active.sock >= 0)
2797 uschar * greeting_cmd;
2799 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2801 uschar *message = string_sprintf("failed to expand helo_data: %s",
2802 expand_string_message);
2803 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2808 #ifndef DISABLE_PIPE_CONNECT
2809 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2810 We're unlikely to get the group sent and delivered before the server sends its
2811 banner, but it's still worth sending as a group.
2812 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2815 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2817 sx->peer_offered = sx->ehlo_resp.crypted_features;
2818 if ((sx->early_pipe_active =
2819 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2820 DEBUG(D_transport) debug_printf("Using cached crypted PIPECONNECT\n");
2823 #ifdef EXPERIMMENTAL_ESMTP_LIMITS
2824 /* As we are about to send another EHLO, forget any LIMITS received so far. */
2825 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom = 0;
2826 if ((sx->max_mail = sx->conn_args.tblock->connection_max_message) == 0)
2827 sx->max_mail = UNLIMITED_ADDRS;
2828 sx->max_rcpt = expand_max_rcpt(sx->conn_args.tblock->max_addresses);
2829 sx->single_rcpt_domain = FALSE;
2832 /* For SMTPS we need to wait for the initial OK response. */
2834 #ifndef DISABLE_PIPE_CONNECT
2835 if (sx->early_pipe_active)
2837 sx->pending_BANNER = TRUE;
2838 sx->outblock.cmd_count = 1;
2842 if (!smtp_reap_banner(sx))
2843 goto RESPONSE_FAILED;
2846 greeting_cmd = US"LHLO";
2848 greeting_cmd = US"EHLO";
2851 greeting_cmd = US"HELO";
2853 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2856 if (smtp_write_command(sx,
2857 #ifndef DISABLE_PIPE_CONNECT
2858 sx->early_pipe_active ? SCMD_BUFFER :
2861 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2864 #ifndef DISABLE_PIPE_CONNECT
2865 if (sx->early_pipe_active)
2866 sx->pending_EHLO = TRUE;
2870 if (!smtp_reap_ehlo(sx))
2873 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2874 cert late, under TLS1.3 - which means here; the first time we try to
2875 receive crypted data. Treat it as if it was a connect-time failure.
2876 See also the early-pipe equivalent... which will be hard; every call
2877 to sync_responses will need to check the result.
2878 It would be nicer to have GnuTLS check the cert during the handshake.
2879 Can it do that, with all the flexibility we need? */
2881 tls_errstr = US"error on first read";
2882 goto TLS_CONN_FAILED;
2885 goto RESPONSE_FAILED;
2887 smtp_peer_options = 0;
2891 /* If the host is required to use a secure channel, ensure that we
2895 # ifdef SUPPORT_DANE
2896 || sx->conn_args.dane
2898 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2901 errno = ERRNO_TLSREQUIRED;
2902 message = string_sprintf("a TLS session is required, but %s",
2903 smtp_peer_options & OPTION_TLS
2904 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2905 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2906 if (sx->conn_args.dane)
2907 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2908 smtp_peer_options & OPTION_TLS
2909 ? US"validation-failure" /* could do with better detail */
2910 : US"starttls-not-supported",
2915 #endif /*DISABLE_TLS*/
2917 /* If TLS is active, we have just started it up and re-done the EHLO command,
2918 so its response needs to be analyzed. If TLS is not active and this is a
2919 continued session down a previously-used socket, we haven't just done EHLO, so
2922 if ( !continue_hostname
2924 || tls_out.active.sock >= 0
2928 if (sx->esmtp || sx->lmtp)
2930 #ifndef DISABLE_PIPE_CONNECT
2931 if (!sx->early_pipe_active)
2934 sx->peer_offered = ehlo_response(sx->buffer,
2936 #ifndef DISABLE_PIPE_CONNECT
2937 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2938 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2939 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2940 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2944 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2947 # ifdef SUPPORT_I18N
2948 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2949 /*XXX if we hand peercaps on to continued-conn processes,
2950 must not depend on this addr */
2954 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2957 #ifndef DISABLE_PIPE_CONNECT
2958 if (tls_out.active.sock >= 0)
2959 sx->ehlo_resp.crypted_features = sx->peer_offered;
2962 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2963 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2965 ehlo_response_limits_read(sx);
2966 ehlo_response_limits_apply(sx);
2971 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2972 lmtp_ignore_quota option was set. */
2974 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2976 /* If the response to EHLO specified support for the SIZE parameter, note
2977 this, provided size_addition is non-negative. */
2979 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2981 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2982 the current host, esmtp will be false, so PIPELINING can never be used. If
2983 the current host matches hosts_avoid_pipelining, don't do it. */
2985 if ( sx->peer_offered & OPTION_PIPE
2986 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2987 smtp_peer_options |= OPTION_PIPE;
2989 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2990 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2992 if ( sx->peer_offered & OPTION_CHUNKING
2993 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) == OK)
2994 smtp_peer_options |= OPTION_CHUNKING;
2996 if (smtp_peer_options & OPTION_CHUNKING)
2997 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2999 #ifndef DISABLE_PRDR
3000 if ( sx->peer_offered & OPTION_PRDR
3001 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) == OK)
3002 smtp_peer_options |= OPTION_PRDR;
3004 if (smtp_peer_options & OPTION_PRDR)
3005 DEBUG(D_transport) debug_printf("PRDR usable\n");
3008 /* Note if the server supports DSN */
3009 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
3010 DEBUG(D_transport) debug_printf("%susing DSN\n",
3011 sx->peer_offered & OPTION_DSN ? "" : "not ");
3013 #ifndef DISABLE_PIPE_CONNECT
3014 if ( sx->early_pipe_ok
3015 && !sx->early_pipe_active
3016 && tls_out.active.sock >= 0
3017 && smtp_peer_options & OPTION_PIPE
3018 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
3019 & OPTION_EARLY_PIPE)
3021 DEBUG(D_transport) debug_printf("PIPECONNECT usable in future for this IP\n");
3022 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
3023 write_ehlo_cache_entry(sx);
3027 /* Note if the response to EHLO specifies support for the AUTH extension.
3028 If it has, check that this host is one we want to authenticate to, and do
3029 the business. The host name and address must be available when the
3030 authenticator's client driver is running. */
3032 switch (yield = smtp_auth(sx))
3034 default: goto SEND_QUIT;
3036 case FAIL_SEND: goto SEND_FAILED;
3037 case FAIL: goto RESPONSE_FAILED;
3041 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
3043 /* The setting up of the SMTP call is now complete. Any subsequent errors are
3044 message-specific. */
3046 sx->setting_up = FALSE;
3049 if (sx->addrlist->prop.utf8_msg)
3053 /* If the transport sets a downconversion mode it overrides any set by ACL
3056 if ((s = ob->utf8_downconvert))
3058 if (!(s = expand_string(s)))
3060 message = string_sprintf("failed to expand utf8_downconvert: %s",
3061 expand_string_message);
3062 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
3068 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
3069 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3071 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
3072 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3074 case '-': if (s[1] == '1')
3076 sx->addrlist->prop.utf8_downcvt = FALSE;
3077 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
3083 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
3084 && !sx->addrlist->prop.utf8_downcvt_maybe;
3085 DEBUG(D_transport) if (!sx->utf8_needed)
3086 debug_printf("utf8: %s downconvert\n",
3087 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
3090 /* If this is an international message we need the host to speak SMTPUTF8 */
3091 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
3093 errno = ERRNO_UTF8_FWD;
3094 goto RESPONSE_FAILED;
3096 #endif /*SUPPORT_I18N*/
3105 if (errno == ECONNREFUSED) /* first-read error on a TFO conn */
3107 /* There is a testing facility for simulating a connection timeout, as I
3108 can't think of any other way of doing this. It converts a connection
3109 refused into a timeout if the timeout is set to 999999. This is done for
3110 a 3whs connection in ip_connect(), but a TFO connection does not error
3111 there - instead it gets ECONNREFUSED on the first data read. Tracking
3112 that a TFO really was done is too hard, or we would set a
3113 sx->pending_conn_done bit and test that in smtp_reap_banner() and
3114 smtp_reap_ehlo(). That would let us also add the conn-timeout to the
3117 if (f.running_in_test_harness && ob->connect_timeout == 999999)
3119 set_errno_nohost(sx->addrlist,
3120 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
3121 sx->verify ? US strerror(errno) : NULL,
3122 DEFER, FALSE, &sx->delivery_start);
3123 sx->send_quit = FALSE;
3127 /* really an error on an SMTP read */
3129 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
3130 sx->buffer, &code, &message, &pass_message);
3136 message = US string_sprintf("smtp send to %s [%s] failed: %s",
3137 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
3138 sx->send_quit = FALSE;
3144 message = string_sprintf("Remote host closed connection in response to %s"
3145 " (EHLO response was: %s)", smtp_command, sx->buffer);
3146 sx->send_quit = FALSE;
3150 /* This label is jumped to directly when a TLS negotiation has failed,
3151 or was not done for a host for which it is required. Values will be set
3152 in message and errno, and setting_up will always be true. Treat as
3153 a temporary error. */
3157 code = '4', yield = DEFER;
3161 /* The failure happened while setting up the call; see if the failure was
3162 a 5xx response (this will either be on connection, or following HELO - a 5xx
3163 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
3164 fail all addresses, as this host is never going to accept them. For other
3165 errors during setting up (timeouts or whatever), defer all addresses, and
3166 yield DEFER, so that the host is not tried again for a while.
3168 XXX This peeking for another host feels like a layering violation. We want
3169 to note the host as unusable, but down here we shouldn't know if this was
3170 the last host to try for the addr(list). Perhaps the upper layer should be
3171 the one to do set_errno() ? The problem is that currently the addr is where
3172 errno etc. are stashed, but until we run out of hosts to try the errors are
3173 host-specific. Maybe we should enhance the host_item definition? */
3176 sx->ok = FALSE; /* For when reached by GOTO */
3177 set_errno(sx->addrlist, errno, message,
3178 sx->conn_args.host->next
3182 || errno == ERRNO_UTF8_FWD
3186 errno == ECONNREFUSED ? NULL : sx->conn_args.host,
3187 #ifdef EXPERIMENTAL_DSN_INFO
3188 sx->smtp_greeting, sx->helo_response,
3190 &sx->delivery_start);
3197 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
3200 if (sx->cctx.tls_ctx)
3202 if (sx->send_tlsclose)
3204 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
3205 sx->send_tlsclose = FALSE;
3207 sx->cctx.tls_ctx = NULL;
3211 /* Close the socket, and return the appropriate value, first setting
3212 works because the NULL setting is passed back to the calling process, and
3213 remote_max_parallel is forced to 1 when delivering over an existing connection,
3216 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3219 shutdown(sx->cctx.sock, SHUT_WR);
3220 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
3221 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
3222 i--; /* drain socket */
3223 sx->send_quit = FALSE;
3225 (void)close(sx->cctx.sock);
3228 #ifndef DISABLE_EVENT
3229 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL, NULL);
3232 smtp_debug_cmd_report();
3233 continue_transport = NULL;
3234 continue_hostname = NULL;
3241 /* Create the string of options that will be appended to the MAIL FROM:
3242 in the connection context buffer */
3245 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
3247 uschar * p = sx->buffer;
3248 address_item * addr;
3253 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
3254 send it, adding something to the message size to allow for imprecision
3255 and things that get added en route. Exim keeps the number of lines
3256 in a message, so we can give an accurate value for the original message, but we
3257 need some additional to handle added headers. (Double "." characters don't get
3258 included in the count.) */
3260 if ( message_size > 0
3261 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
3263 /*XXX problem here under spool_files_wireformat?
3264 Or just forget about lines? Or inflate by a fixed proportion? */
3266 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
3270 #ifndef DISABLE_PRDR
3271 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
3274 sx->prdr_active = FALSE;
3275 if (smtp_peer_options & OPTION_PRDR)
3276 for (address_item * addr = addrlist; addr; addr = addr->next)
3277 if (addr->transport_return == PENDING_DEFER)
3279 for (addr = addr->next; addr; addr = addr->next)
3280 if (addr->transport_return == PENDING_DEFER)
3281 { /* at least two recipients to send */
3282 sx->prdr_active = TRUE;
3283 sprintf(CS p, " PRDR"); p += 5;
3291 /* If it supports internationalised messages, and this meesage need that,
3294 if ( sx->peer_offered & OPTION_UTF8
3295 && addrlist->prop.utf8_msg
3296 && !addrlist->prop.utf8_downcvt
3298 Ustrcpy(p, US" SMTPUTF8"), p += 9;
3301 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3302 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3303 addr && address_count < sx->max_rcpt; /*XXX maybe also || sx->single_rcpt_domain ? */
3304 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3307 if (!(addr->dsn_flags & rf_dsnlasthop))
3309 sx->dsn_all_lasthop = FALSE;
3314 /* Add any DSN flags to the mail command */
3316 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3318 if (dsn_ret == dsn_ret_hdrs)
3319 { Ustrcpy(p, US" RET=HDRS"); p += 9; }
3320 else if (dsn_ret == dsn_ret_full)
3321 { Ustrcpy(p, US" RET=FULL"); p += 9; }
3325 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3330 /* If an authenticated_sender override has been specified for this transport
3331 instance, expand it. If the expansion is forced to fail, and there was already
3332 an authenticated_sender for this message, the original value will be used.
3333 Other expansion failures are serious. An empty result is ignored, but there is
3334 otherwise no check - this feature is expected to be used with LMTP and other
3335 cases where non-standard addresses (e.g. without domains) might be required. */
3337 return smtp_mail_auth_str(sx, p, addrlist) ? ERROR : OK;
3342 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3344 uschar * p = sx->buffer;
3347 /* Add any DSN flags to the rcpt command */
3349 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3351 if (addr->dsn_flags & rf_dsnflags)
3355 Ustrcpy(p, US" NOTIFY=");
3357 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3359 if (!first) *p++ = ',';
3361 Ustrcpy(p, rf_names[i]);
3366 if (addr->dsn_orcpt)
3368 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3379 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3380 -1 MAIL response error
3381 -2 any non-MAIL read i/o error
3382 -3 non-MAIL response timeout
3383 -4 internal error; channel still usable
3388 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3390 address_item * addr;
3391 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3392 address_item * restart_addr = NULL;
3394 int address_count, pipe_limit;
3397 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3403 /* From here until we send the DATA command, we can make use of PIPELINING
3404 if the server host supports it. The code has to be able to check the responses
3405 at any point, for when the buffer fills up, so we write it totally generally.
3406 When PIPELINING is off, each command written reports that it has flushed the
3409 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3412 uschar * s = sx->from_addr;
3414 uschar * errstr = NULL;
3416 /* If we must downconvert, do the from-address here. Remember we had to
3417 for the to-addresses (done below), and also (ugly) for re-doing when building
3418 the delivery log line. */
3420 if ( sx->addrlist->prop.utf8_msg
3421 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3424 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3426 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, &sx->delivery_start);
3430 setflag(sx->addrlist, af_utf8_downcvt);
3434 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3435 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3438 mail_command = string_copy(big_buffer); /* Save for later error message */
3442 case -1: /* Transmission error */
3445 case +1: /* Cmd was sent */
3446 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3447 (SOB sx->conn_args.ob)->command_timeout))
3449 if (errno == 0 && sx->buffer[0] == '4')
3451 errno = ERRNO_MAIL4XX;
3452 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3456 sx->pending_MAIL = FALSE;
3459 /* otherwise zero: command queued for pipeline */
3462 /* Pass over all the relevant recipient addresses for this host, which are the
3463 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3464 several before we have to read the responses for those seen so far. This
3465 checking is done by a subroutine because it also needs to be done at the end.
3466 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3467 the next one if not all are sent.
3469 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3470 last address because we want to abort if any recipients have any kind of
3471 problem, temporary or permanent. We know that all recipient addresses will have
3472 the PENDING_DEFER status, because only one attempt is ever made, and we know
3473 that max_rcpt will be large, so all addresses will be done at once.
3475 For verify we flush the pipeline after any (the only) rcpt address. */
3477 for (addr = sx->first_addr, address_count = 0, pipe_limit = 100;
3478 addr && address_count < sx->max_rcpt;
3479 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3485 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3486 if ( sx->single_rcpt_domain /* restriction on domains */
3487 && address_count > 0 /* not first being sent */
3488 && Ustrcmp(addr->domain, sx->first_addr->domain) != 0 /* dom diff from first */
3491 DEBUG(D_transport) debug_printf("skipping different domain %s\n", addr->domain);
3493 /* Ensure the smtp-response reaper does not think the address had a RCPT
3494 command sent for it. Reset to PENDING_DEFER in smtp_deliver(), where we
3495 goto SEND_MESSAGE. */
3497 addr->transport_return = SKIP;
3498 if (!restart_addr) restart_addr = addr; /* note restart point */
3499 continue; /* skip this one */
3503 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3504 ? dsn_support_yes : dsn_support_no;
3507 if (pipe_limit-- <= 0)
3508 { no_flush = FALSE; pipe_limit = 100; }
3510 no_flush = pipelining_active && !sx->verify
3511 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3513 build_rcptcmd_options(sx, addr);
3515 /* Now send the RCPT command, and process outstanding responses when
3516 necessary. After a timeout on RCPT, we just end the function, leaving the
3517 yield as OK, because this error can often mean that there is a problem with
3518 just one address, so we don't want to delay the host. */
3520 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3523 if ( testflag(sx->addrlist, af_utf8_downcvt)
3524 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3527 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3528 errno = ERRNO_EXPANDFAIL;
3529 return -5; /*XXX too harsh? */
3533 cmds_sent = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3534 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3536 if (cmds_sent < 0) return -5;
3539 switch(sync_responses(sx, cmds_sent, 0))
3541 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3542 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3545 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3546 if (!sx->lmtp) /* can't tell about progress yet */
3547 sx->completed_addr = TRUE;
3548 case 0: /* No 2xx or 5xx, but no probs */
3549 /* If any RCPT got a 452 response then next_addr has been updated
3550 for restarting with a new MAIL on the same connection. Send no more
3551 RCPTs for this MAIL. */
3555 DEBUG(D_transport) debug_printf("seen 452 too-many-rcpts\n");
3556 sx->RCPT_452 = FALSE;
3557 /* sx->next_addr has been reset for fast_retry */
3562 case -1: return -3; /* Timeout on RCPT */
3563 case -2: return -2; /* non-MAIL read i/o error */
3564 default: return -1; /* any MAIL error */
3566 #ifndef DISABLE_PIPE_CONNECT
3567 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3568 case -5: return -1; /* TLS first-read error */
3572 } /* Loop for next address */
3574 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3575 sx->next_addr = restart_addr ? restart_addr : addr;
3577 sx->next_addr = addr;
3584 /*****************************************************
3585 * Proxy TLS connection for another transport process *
3586 ******************************************************/
3588 Close the unused end of the pipe, fork once more, then use the given buffer
3589 as a staging area, and select on both the given fd and the TLS'd client-fd for
3590 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3591 Do blocking full-size writes, and reads under a timeout. Once both input
3592 channels are closed, exit the process.
3596 buf space to use for buffering
3597 bufsiz size of buffer
3598 pfd pipe filedescriptor array; [0] is comms to proxied process
3599 timeout per-read timeout, seconds
3600 host hostname of remote
3606 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3607 int timeout, const uschar * host)
3609 struct pollfd p[2] = {{.fd = tls_out.active.sock, .events = POLLIN},
3610 {.fd = pfd[0], .events = POLLIN}};
3612 BOOL send_tls_shutdown = TRUE;
3615 if ((rc = exim_fork(US"tls-proxy")))
3616 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3618 set_process_info("proxying TLS connection for continued transport to %s\n", host);
3622 time_t time_left = timeout;
3623 time_t time_start = time(NULL);
3628 rc = poll(p, 2, time_left * 1000);
3630 if (rc < 0 && errno == EINTR)
3631 if ((time_left -= time(NULL) - time_start) > 0) continue;
3635 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3639 /* For errors where not readable, bomb out */
3641 if (p[0].revents & POLLERR || p[1].revents & POLLERR)
3643 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3644 p[0].revents & POLLERR ? "tls" : "proxy");
3645 if (!(p[0].revents & POLLIN || p[1].events & POLLIN))
3647 DEBUG(D_transport) debug_printf("- but also readable; no exit yet\n");
3650 while (rc < 0 || !(p[0].revents & POLLIN || p[1].revents & POLLIN));
3652 /* handle inbound data */
3653 if (p[0].revents & POLLIN)
3654 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0) /* Expect -1 for EOF; */
3655 { /* that reaps the TLS Close Notify record */
3657 shutdown(pfd[0], SHUT_WR);
3661 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3662 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3664 /* Handle outbound data. We cannot combine payload and the TLS-close
3665 due to the limitations of the (pipe) channel feeding us. Maybe use a unix-domain
3667 if (p[1].revents & POLLIN)
3668 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3672 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
3673 (void) setsockopt(tls_out.active.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
3675 tls_shutdown_wr(ct_ctx);
3676 send_tls_shutdown = FALSE;
3677 shutdown(tls_out.active.sock, SHUT_WR);
3680 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3681 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3684 while (p[0].fd >= 0 || p[1].fd >= 0);
3687 if (send_tls_shutdown) tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3689 testharness_pause_ms(100); /* let logging complete */
3690 exim_exit(EXIT_SUCCESS);
3695 /*************************************************
3696 * Deliver address list to given host *
3697 *************************************************/
3699 /* If continue_hostname is not null, we get here only when continuing to
3700 deliver down an existing channel. The channel was passed as the standard
3701 input. TLS is never active on a passed channel; the previous process either
3702 closes it down before passing the connection on, or inserts a TLS-proxy
3703 process and passes on a cleartext conection.
3705 Otherwise, we have to make a connection to the remote host, and do the
3706 initial protocol exchange.
3708 When running as an MUA wrapper, if the sender or any recipient is rejected,
3709 temporarily or permanently, we force failure for all recipients.
3712 addrlist chain of potential addresses to deliver; only those whose
3713 transport_return field is set to PENDING_DEFER are currently
3714 being processed; others should be skipped - they have either
3715 been delivered to an earlier host or IP address, or been
3716 failed by one of them.
3717 host host to deliver to
3718 host_af AF_INET or AF_INET6
3719 defport default TCP/IP port to use if host does not specify, in host
3721 interface interface to bind to, or NULL
3722 tblock transport instance block
3723 message_defer set TRUE if yield is OK, but all addresses were deferred
3724 because of a non-recipient, non-host failure, that is, a
3725 4xx response to MAIL FROM, DATA, or ".". This is a defer
3726 that is specific to the message.
3727 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3728 a second attempt after TLS initialization fails
3730 Returns: OK - the connection was made and the delivery attempted;
3731 the result for each address is in its data block.
3732 DEFER - the connection could not be made, or something failed
3733 while setting up the SMTP session, or there was a
3734 non-message-specific error, such as a timeout.
3735 ERROR - a filter command is specified for this transport,
3736 and there was a problem setting it up; OR helo_data
3737 or add_headers or authenticated_sender is specified
3738 for this transport, and the string failed to expand
3740 For all non-OK returns the first addr of the list carries the
3741 time taken for the attempt.
3745 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3746 uschar *interface, transport_instance *tblock,
3747 BOOL *message_defer, BOOL suppress_tls)
3749 smtp_transport_options_block * ob = SOB tblock->options_block;
3754 uschar *message = NULL;
3755 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3756 smtp_context * sx = store_get(sizeof(*sx), GET_TAINTED); /* tainted, for the data buffers */
3757 BOOL pass_message = FALSE;
3758 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3759 BOOL mail_limit = FALSE;
3764 BOOL tcw_done = FALSE, tcw = FALSE;
3766 *message_defer = FALSE;
3768 memset(sx, 0, sizeof(*sx));
3769 sx->addrlist = addrlist;
3770 sx->conn_args.host = host;
3771 sx->conn_args.host_af = host_af;
3773 sx->conn_args.interface = interface;
3774 sx->helo_data = NULL;
3775 sx->conn_args.tblock = tblock;
3776 sx->conn_args.sock = -1;
3777 gettimeofday(&sx->delivery_start, NULL);
3778 sx->sync_addr = sx->first_addr = addrlist;
3785 /* Get the channel set up ready for a message, MAIL FROM being the next
3786 SMTP command to send. */
3788 if ((rc = smtp_setup_conn(sx, suppress_tls)) != OK)
3790 timesince(&addrlist->delivery_time, &sx->delivery_start);
3796 /* If the connection used DANE, ignore for now any addresses with incompatible
3797 domains. The SNI has to be the domain. Arrange a whole new TCP conn later,
3798 just in case only TLS isn't enough. */
3800 if (sx->conn_args.dane)
3802 const uschar * dane_domain = sx->first_addr->domain;
3804 for (address_item * a = sx->first_addr->next; a; a = a->next)
3805 if ( a->transport_return == PENDING_DEFER
3806 && Ustrcmp(dane_domain, a->domain) != 0)
3808 DEBUG(D_transport) debug_printf("DANE: holding %s for later\n", a->domain);
3810 a->transport_return = DANE;
3815 /* If there is a filter command specified for this transport, we can now
3816 set it up. This cannot be done until the identity of the host is known. */
3818 if (tblock->filter_command)
3820 transport_filter_timeout = tblock->filter_timeout;
3822 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3825 if (!transport_set_up_command(&transport_filter_argv,
3826 tblock->filter_command, TRUE, DEFER, addrlist, FALSE,
3827 string_sprintf("%.50s transport filter", tblock->name), NULL))
3829 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3830 FALSE, &sx->delivery_start);
3835 if ( transport_filter_argv
3836 && *transport_filter_argv
3837 && **transport_filter_argv
3838 && smtp_peer_options & OPTION_CHUNKING
3839 #ifndef DISABLE_DKIM
3840 /* When dkim signing, chunking is handled even with a transport-filter */
3841 && !(ob->dkim.dkim_private_key && ob->dkim.dkim_domain && ob->dkim.dkim_selector)
3842 && !ob->dkim.force_bodyhash
3846 smtp_peer_options &= ~OPTION_CHUNKING;
3847 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3851 /* For messages that have more than the maximum number of envelope recipients,
3852 we want to send several transactions down the same SMTP connection. (See
3853 comments in deliver.c as to how this reconciles, heuristically, with
3854 remote_max_parallel.) This optimization was added to Exim after the following
3855 code was already working. The simplest way to put it in without disturbing the
3856 code was to use a goto to jump back to this point when there is another
3857 transaction to handle. */
3860 sx->from_addr = return_path;
3861 sx->sync_addr = sx->first_addr;
3863 sx->send_rset = TRUE;
3864 sx->completed_addr = FALSE;
3867 /* If we are a continued-connection-after-verify the MAIL and RCPT
3868 commands were already sent; do not re-send but do mark the addrs as
3869 having been accepted up to RCPT stage. A traditional cont-conn
3870 always has a sequence number greater than one. */
3872 if (continue_hostname && continue_sequence == 1)
3874 /* sx->pending_MAIL = FALSE; */
3876 /* sx->next_addr = NULL; */
3878 for (address_item * addr = addrlist; addr; addr = addr->next)
3879 addr->transport_return = PENDING_OK;
3883 /* Initiate a message transfer. */
3885 switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))
3888 case -1: case -2: goto RESPONSE_FAILED;
3889 case -3: goto END_OFF;
3890 case -4: goto SEND_QUIT;
3891 default: goto SEND_FAILED;
3894 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3895 permanently or temporarily. We should have flushed and synced after the last
3903 for (a = sx->first_addr, cnt = 0; a && cnt < sx->max_rcpt; a = a->next, cnt++)
3904 if (a->transport_return != PENDING_OK)
3906 /*XXX could we find a better errno than 0 here? */
3907 set_errno_nohost(addrlist, 0, a->message, FAIL,
3908 testflag(a, af_pass_message), &sx->delivery_start);
3915 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3916 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3917 have a good recipient buffered up if we are pipelining. We don't want to waste
3918 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3919 are pipelining. The responses are all handled by sync_responses().
3920 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3923 if ( !(smtp_peer_options & OPTION_CHUNKING)
3924 && (sx->ok || (pipelining_active && !mua_wrapper)))
3926 int count = smtp_write_command(sx, SCMD_FLUSH, "DATA\r\n");
3928 if (count < 0) goto SEND_FAILED;
3929 switch(sync_responses(sx, count, sx->ok ? +1 : -1))
3931 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3932 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3935 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3936 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
3937 case 0: break; /* No 2xx or 5xx, but no probs */
3939 case -1: goto END_OFF; /* Timeout on RCPT */
3941 #ifndef DISABLE_PIPE_CONNECT
3942 case -5: /* TLS first-read error */
3943 case -4: HDEBUG(D_transport)
3944 debug_printf("failed reaping pipelined cmd responses\n");
3946 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3948 pipelining_active = FALSE;
3949 data_command = string_copy(big_buffer); /* Save for later error message */
3952 /* If there were no good recipients (but otherwise there have been no
3953 problems), just set ok TRUE, since we have handled address-specific errors
3954 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3955 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3956 well as body. Set the appropriate timeout value to be used for each chunk.
3957 (Haven't been able to make it work using select() for writing yet.) */
3960 && (!(smtp_peer_options & OPTION_CHUNKING) || !pipelining_active))
3962 /* Save the first address of the next batch. */
3963 sx->first_addr = sx->next_addr;
3969 transport_ctx tctx = {
3970 .u = {.fd = sx->cctx.sock}, /*XXX will this need TLS info? */
3973 .check_string = US".",
3974 .escape_string = US"..", /* Escaping strings */
3976 topt_use_crlf | topt_escape_headers
3977 | (tblock->body_only ? topt_no_headers : 0)
3978 | (tblock->headers_only ? topt_no_body : 0)
3979 | (tblock->return_path_add ? topt_add_return_path : 0)
3980 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3981 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3984 /* If using CHUNKING we need a callback from the generic transport
3985 support to us, for the sending of BDAT smtp commands and the reaping
3986 of responses. The callback needs a whole bunch of state so set up
3987 a transport-context structure to be passed around. */
3989 if (smtp_peer_options & OPTION_CHUNKING)
3991 tctx.check_string = tctx.escape_string = NULL;
3992 tctx.options |= topt_use_bdat;
3993 tctx.chunk_cb = smtp_chunk_cmd_callback;
3994 sx->pending_BDAT = FALSE;
3995 sx->good_RCPT = sx->ok;
3997 tctx.smtp_context = sx;
4000 tctx.options |= topt_end_dot;
4002 /* Save the first address of the next batch. */
4003 sx->first_addr = sx->next_addr;
4005 /* Responses from CHUNKING commands go in buffer. Otherwise,
4006 there has not been a response. */
4010 sigalrm_seen = FALSE;
4011 transport_write_timeout = ob->data_timeout;
4012 smtp_command = US"sending data block"; /* For error messages */
4013 DEBUG(D_transport|D_v)
4014 if (smtp_peer_options & OPTION_CHUNKING)
4015 debug_printf(" will write message using CHUNKING\n");
4017 debug_printf(" SMTP>> (writing message)\n");
4018 transport_count = 0;
4020 #ifndef DISABLE_DKIM
4022 # ifdef MEASURE_TIMING
4024 gettimeofday(&t0, NULL);
4026 dkim_exim_sign_init();
4027 # ifdef EXPERIMENTAL_ARC
4029 uschar * s = ob->arc_sign;
4032 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
4034 if (!f.expand_string_forcedfail)
4036 message = US"failed to expand arc_sign";
4043 /* Ask dkim code to hash the body for ARC */
4044 (void) arc_ams_setup_sign_bodyhash();
4045 ob->dkim.force_bodyhash = TRUE;
4050 # ifdef MEASURE_TIMING
4051 report_time_since(&t0, US"dkim_exim_sign_init (delta)");
4056 /* See if we can pipeline QUIT. Reasons not to are
4057 - pipelining not active
4058 - not ok to send quit
4059 - errors in amtp transation responses
4060 - more addrs to send for this message or this host
4061 - this message was being retried
4062 - more messages for this host
4063 If we can, we want the message-write to not flush (the tail end of) its data out. */
4065 if ( sx->pipelining_used
4066 && (sx->ok && sx->completed_addr || smtp_peer_options & OPTION_CHUNKING)
4068 && !(sx->first_addr || f.continue_more)
4069 && f.deliver_firsttime
4072 smtp_compare_t t_compare =
4073 {.tblock = tblock, .current_sender_address = sender_address};
4078 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4079 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4083 transport_check_waiting(tblock->name, host->name,
4084 tblock->connection_max_messages, new_message_id,
4085 (oicf)smtp_are_same_identities, (void*)&t_compare);
4088 HDEBUG(D_transport) debug_printf("will pipeline QUIT\n");
4089 tctx.options |= topt_no_flush;
4093 #ifndef DISABLE_DKIM
4094 sx->ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
4096 sx->ok = transport_write_message(&tctx, 0);
4099 /* transport_write_message() uses write() because it is called from other
4100 places to write to non-sockets. This means that under some OS (e.g. Solaris)
4101 it can exit with "Broken pipe" as its error. This really means that the
4102 socket got closed at the far end. */
4104 transport_write_timeout = 0; /* for subsequent transports */
4106 /* Failure can either be some kind of I/O disaster (including timeout),
4107 or the failure of a transport filter or the expansion of added headers.
4108 Or, when CHUNKING, it can be a protocol-detected failure. */
4111 if (message) goto SEND_FAILED;
4112 else goto RESPONSE_FAILED;
4114 /* We used to send the terminating "." explicitly here, but because of
4115 buffering effects at both ends of TCP/IP connections, you don't gain
4116 anything by keeping it separate, so it might as well go in the final
4117 data buffer for efficiency. This is now done by setting the topt_end_dot
4120 smtp_command = US"end of data";
4122 /* If we can pipeline a QUIT with the data them send it now. If a new message
4123 for this host appeared in the queue while data was being sent, we will not see
4124 it and it will have to wait for a queue run. If there was one but another
4125 thread took it, we might attempt to send it - but locking of spoolfiles will
4126 detect that. Use _MORE to get QUIT in FIN segment. */
4128 if (tcw_done && !tcw)
4130 /*XXX jgh 2021/03/10 google et. al screwup. G, at least, sends TCP FIN in response to TLS
4131 close-notify. Under TLS 1.3, violating RFC.
4132 However, TLS 1.2 does not have half-close semantics. */
4134 if ( sx->cctx.tls_ctx
4135 #if 0 && !defined(DISABLE_TLS)
4136 && Ustrcmp(tls_out.ver, "TLS1.3") != 0
4138 || !f.deliver_firsttime
4140 { /* Send QUIT now and not later */
4141 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
4142 sx->send_quit = FALSE;
4145 { /* add QUIT to the output buffer */
4146 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4147 sx->send_quit = FALSE; /* avoid sending it later */
4150 if (sx->cctx.tls_ctx && sx->send_tlsclose) /* need to send TLS Close Notify */
4152 # ifdef EXIM_TCP_CORK /* Use _CORK to get Close Notify in FIN segment */
4153 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4155 tls_shutdown_wr(sx->cctx.tls_ctx);
4156 sx->send_tlsclose = FALSE; /* avoid later repeat */
4159 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4160 shutdown(sx->cctx.sock, SHUT_WR); /* flush output buffer, with TCP FIN */
4164 if (smtp_peer_options & OPTION_CHUNKING && sx->cmd_count > 1)
4166 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
4167 switch(sync_responses(sx, sx->cmd_count-1, 0))
4169 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
4170 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
4173 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
4174 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
4175 case 0: break; /* No 2xx or 5xx, but no probs */
4177 case -1: goto END_OFF; /* Timeout on RCPT */
4179 #ifndef DISABLE_PIPE_CONNECT
4180 case -5: /* TLS first-read error */
4181 case -4: HDEBUG(D_transport)
4182 debug_printf("failed reaping pipelined cmd responses\n");
4184 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
4188 #ifndef DISABLE_PRDR
4189 /* For PRDR we optionally get a partial-responses warning followed by the
4190 individual responses, before going on with the overall response. If we don't
4191 get the warning then deal with per non-PRDR. */
4195 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '3', ob->final_timeout);
4196 if (!sx->ok && errno == 0) switch(sx->buffer[0])
4198 case '2': sx->prdr_active = FALSE;
4201 case '4': errno = ERRNO_DATA4XX;
4202 addrlist->more_errno |=
4203 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4210 /* For non-PRDR SMTP, we now read a single response that applies to the
4211 whole message. If it is OK, then all the addresses have been delivered. */
4215 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4217 if (!sx->ok && errno == 0 && sx->buffer[0] == '4')
4219 errno = ERRNO_DATA4XX;
4220 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4224 /* For LMTP, we get back a response for every RCPT command that we sent;
4225 some may be accepted and some rejected. For those that get a response, their
4226 status is fixed; any that are accepted have been handed over, even if later
4227 responses crash - at least, that's how I read RFC 2033.
4229 If all went well, mark the recipient addresses as completed, record which
4230 host/IPaddress they were delivered to, and cut out RSET when sending another
4231 message down the same channel. Write the completed addresses to the journal
4232 now so that they are recorded in case there is a crash of hardware or
4233 software before the spool gets updated. Also record the final SMTP
4234 confirmation if needed (for SMTP only). */
4239 struct timeval delivery_time;
4241 uschar * conf = NULL;
4243 timesince(&delivery_time, &sx->delivery_start);
4244 sx->send_rset = FALSE;
4245 pipelining_active = FALSE;
4247 /* Set up confirmation if needed - applies only to SMTP */
4250 #ifdef DISABLE_EVENT
4251 LOGGING(smtp_confirmation) &&
4256 const uschar * s = string_printing(sx->buffer);
4257 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4258 conf = s == sx->buffer ? US string_copy(s) : US s;
4261 /* Process all transported addresses - for LMTP or PRDR, read a status for
4262 each one. We used to drop out at first_addr, until someone returned a 452
4263 followed by a 250... and we screwed up the accepted addresses. */
4265 for (address_item * addr = addrlist; addr; addr = addr->next)
4267 if (addr->transport_return != PENDING_OK) continue;
4269 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
4270 remaining addresses. Otherwise, it's a return code for just the one
4271 address. For temporary errors, add a retry item for the address so that
4272 it doesn't get tried again too soon. */
4274 #ifndef DISABLE_PRDR
4275 if (sx->lmtp || sx->prdr_active)
4280 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4283 if (errno != 0 || sx->buffer[0] == 0) goto RESPONSE_FAILED;
4284 addr->message = string_sprintf(
4285 #ifndef DISABLE_PRDR
4286 "%s error after %s: %s", sx->prdr_active ? "PRDR":"LMTP",
4288 "LMTP error after %s: %s",
4290 data_command, string_printing(sx->buffer));
4291 setflag(addr, af_pass_message); /* Allow message to go to user */
4292 if (sx->buffer[0] == '5')
4293 addr->transport_return = FAIL;
4296 errno = ERRNO_DATA4XX;
4297 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4298 addr->transport_return = DEFER;
4299 #ifndef DISABLE_PRDR
4300 if (!sx->prdr_active)
4302 retry_add_item(addr, addr->address_retry_key, 0);
4306 sx->completed_addr = TRUE; /* NOW we can set this flag */
4307 if (LOGGING(smtp_confirmation))
4309 const uschar *s = string_printing(sx->buffer);
4310 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4311 conf = (s == sx->buffer) ? US string_copy(s) : US s;
4315 /* SMTP, or success return from LMTP for this address. Pass back the
4316 actual host that was used. */
4318 addr->transport_return = OK;
4319 addr->host_used = host;
4320 addr->delivery_time = delivery_time;
4321 addr->special_action = flag;
4322 addr->message = conf;
4324 if (tcp_out_fastopen)
4326 setflag(addr, af_tcp_fastopen_conn);
4327 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
4328 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
4330 if (sx->pipelining_used) setflag(addr, af_pipelining);
4331 #ifndef DISABLE_PIPE_CONNECT
4332 if (sx->early_pipe_active) setflag(addr, af_early_pipe);
4334 #ifndef DISABLE_PRDR
4335 if (sx->prdr_active) setflag(addr, af_prdr_used);
4337 if (smtp_peer_options & OPTION_CHUNKING) setflag(addr, af_chunking_used);
4340 #ifndef DISABLE_PRDR
4341 if (!sx->prdr_active)
4344 /* Update the journal. For homonymic addresses, use the base address plus
4345 the transport name. See lots of comments in deliver.c about the reasons
4346 for the complications when homonyms are involved. Just carry on after
4347 write error, as it may prove possible to update the spool file later. */
4349 if (testflag(addr, af_homonym))
4350 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4352 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4354 DEBUG(D_deliver) debug_printf("S:journalling %s", sx->buffer);
4355 len = Ustrlen(CS sx->buffer);
4356 if (write(journal_fd, sx->buffer, len) != len)
4357 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4358 "%s: %s", sx->buffer, strerror(errno));
4362 #ifndef DISABLE_PRDR
4363 if (sx->prdr_active)
4365 const uschar * overall_message;
4367 /* PRDR - get the final, overall response. For any non-success
4368 upgrade all the address statuses. */
4370 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4374 if(errno == 0 && sx->buffer[0] == '4')
4376 errno = ERRNO_DATA4XX;
4377 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4379 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4380 if (sx->buffer[0] == '5' || addr->transport_return == OK)
4381 addr->transport_return = PENDING_OK; /* allow set_errno action */
4382 goto RESPONSE_FAILED;
4385 /* Append the overall response to the individual PRDR response for logging
4386 and update the journal, or setup retry. */
4388 overall_message = string_printing(sx->buffer);
4389 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4390 if (addr->transport_return == OK)
4391 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
4393 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4394 if (addr->transport_return == OK)
4396 if (testflag(addr, af_homonym))
4397 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4399 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4401 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx->buffer);
4402 len = Ustrlen(CS sx->buffer);
4403 if (write(journal_fd, sx->buffer, len) != len)
4404 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4405 "%s: %s", sx->buffer, strerror(errno));
4407 else if (addr->transport_return == DEFER)
4408 /*XXX magic value -2 ? maybe host+message ? */
4409 retry_add_item(addr, addr->address_retry_key, -2);
4413 /* Ensure the journal file is pushed out to disk. */
4415 if (EXIMfsync(journal_fd) < 0)
4416 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
4422 /* Handle general (not specific to one address) failures here. The value of ok
4423 is used to skip over this code on the falling through case. A timeout causes a
4424 deferral. Other errors may defer or fail according to the response code, and
4425 may set up a special errno value, e.g. after connection chopped, which is
4426 assumed if errno == 0 and there is no text in the buffer. If control reaches
4427 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
4428 the problem is not related to this specific message. */
4433 uschar * set_message;
4439 /* Clear send_quit flag if needed. Do not set. */
4440 sx->send_quit &= check_response(host, &save_errno, addrlist->more_errno,
4441 sx->buffer, &code, &message, &pass_message);
4449 message = string_sprintf("smtp send to %s [%s] failed: %s",
4450 host->name, host->address, message ? message : US strerror(save_errno));
4451 sx->send_quit = FALSE;
4459 sx->ok = FALSE; /* For when reached by GOTO */
4460 set_message = message;
4462 /* We want to handle timeouts after MAIL or "." and loss of connection after
4463 "." specially. They can indicate a problem with the sender address or with
4464 the contents of the message rather than a real error on the connection. These
4465 cases are treated in the same way as a 4xx response. This next bit of code
4466 does the classification. */
4473 message_error = TRUE;
4477 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4478 Ustrncmp(smtp_command,"end ",4) == 0;
4481 case ERRNO_SMTPCLOSED:
4482 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4485 #ifndef DISABLE_DKIM
4487 /* DKIM signing failure: avoid thinking we pipelined quit,
4488 just abandon the message and close the socket. */
4490 message_error = FALSE;
4491 # ifndef DISABLE_TLS
4492 if (sx->cctx.tls_ctx)
4494 tls_close(sx->cctx.tls_ctx,
4495 sx->send_tlsclose ? TLS_SHUTDOWN_WAIT : TLS_SHUTDOWN_WONLY);
4496 sx->cctx.tls_ctx = NULL;
4502 message_error = FALSE;
4506 /* Handle the cases that are treated as message errors. These are:
4508 (a) negative response or timeout after MAIL
4509 (b) negative response after DATA
4510 (c) negative response or timeout or dropped connection after "."
4511 (d) utf8 support required and not offered
4513 It won't be a negative response or timeout after RCPT, as that is dealt
4514 with separately above. The action in all cases is to set an appropriate
4515 error code for all the addresses, but to leave yield set to OK because the
4516 host itself has not failed. Of course, it might in practice have failed
4517 when we've had a timeout, but if so, we'll discover that at the next
4518 delivery attempt. For a temporary error, set the message_defer flag, and
4519 write to the logs for information if this is not the last host. The error
4520 for the last host will be logged as part of the address's log line. */
4524 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4526 /* If there's an errno, the message contains just the identity of
4531 else /* Anything other than 5 is treated as temporary */
4535 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4537 write_logs(host, message, sx->first_addr ? sx->first_addr->basic_errno : 0);
4539 *message_defer = TRUE;
4542 DEBUG(D_transport) if (sx->cctx.sock >= 0)
4545 if (ioctl(sx->cctx.sock, TIOCOUTQ, &n) == 0)
4546 debug_printf("%d bytes remain in socket output buffer\n", n);
4550 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4551 ".", or some other transportation error. We defer all addresses and yield
4552 DEFER, except for the case of failed add_headers expansion, or a transport
4553 filter failure, when the yield should be ERROR, to stop it trying other
4558 #ifndef DISABLE_PIPE_CONNECT
4559 /* If we were early-pipelinng and the actual EHLO response did not match
4560 the cached value we assumed, we could have detected it and passed a
4561 custom errno through to here. It would be nice to RSET and retry right
4562 away, but to reliably do that we eould need an extra synch point before
4563 we committed to data and that would discard half the gained roundrips.
4564 Or we could summarily drop the TCP connection. but that is also ugly.
4565 Instead, we ignore the possibility (having freshened the cache) and rely
4566 on the server telling us with a nonmessage error if we have tried to
4567 do something it no longer supports. */
4570 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4571 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4575 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host,
4576 #ifdef EXPERIMENTAL_DSN_INFO
4577 sx->smtp_greeting, sx->helo_response,
4579 &sx->delivery_start);
4582 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4583 SMTP session tidily. However, if there were too many addresses to send in one
4584 message (indicated by first_addr being non-NULL) we want to carry on with the
4585 rest of them. Also, it is desirable to send more than one message down the SMTP
4586 connection if there are several waiting, provided we haven't already sent so
4587 many as to hit the configured limit. The function transport_check_waiting looks
4588 for a waiting message and returns its id. Then transport_pass_socket tries to
4589 set up a continued delivery by passing the socket on to another process. The
4590 variable send_rset is FALSE if a message has just been successfully transferred.
4592 If we are already sending down a continued channel, there may be further
4593 addresses not yet delivered that are aimed at the same host, but which have not
4594 been passed in this run of the transport. In this case, continue_more will be
4595 true, and all we should do is send RSET if necessary, and return, leaving the
4598 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4599 do not want to continue with other messages down the same channel, because that
4600 can lead to looping between two or more messages, all with the same,
4601 temporarily failing address(es). [The retry information isn't updated yet, so
4602 new processes keep on trying.] We probably also don't want to try more of this
4603 message's addresses either.
4605 If we have started a TLS session, we have to end it before passing the
4606 connection to a new process. However, not all servers can handle this (Exim
4607 can), so we do not pass such a connection on if the host matches
4608 hosts_nopass_tls. */
4611 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4612 "yield=%d first_address is %sNULL\n", sx->ok, sx->send_quit,
4613 sx->send_rset, f.continue_more, yield, sx->first_addr ? "not " : "");
4615 if (sx->completed_addr && sx->ok && sx->send_quit)
4616 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4617 if (mail_limit = continue_sequence >= sx->max_mail)
4620 debug_printf("reached limit %u for MAILs per conn\n", sx->max_mail);
4625 smtp_compare_t t_compare =
4626 {.tblock = tblock, .current_sender_address = sender_address};
4628 if ( sx->first_addr /* more addrs for this message */
4629 || f.continue_more /* more addrs for continued-host */
4630 || tcw_done && tcw /* more messages for host */
4633 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4634 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4638 transport_check_waiting(tblock->name, host->name,
4639 sx->max_mail, new_message_id,
4640 (oicf)smtp_are_same_identities, (void*)&t_compare)
4647 if (! (sx->ok = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4649 msg = US string_sprintf("smtp send to %s [%s] failed: %s", host->name,
4650 host->address, strerror(errno));
4651 sx->send_quit = FALSE;
4653 else if (! (sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4654 '2', ob->command_timeout)))
4657 sx->send_quit = check_response(host, &errno, 0, sx->buffer, &code, &msg,
4661 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4662 host->name, host->address, msg);
4666 /* Either RSET was not needed, or it succeeded */
4673 int socket_fd = sx->cctx.sock;
4675 if (sx->first_addr) /* More addresses still to be sent */
4676 { /* for this message */
4677 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4678 /* Any that we marked as skipped, reset to do now */
4679 for (address_item * a = sx->first_addr; a; a = a->next)
4680 if (a->transport_return == SKIP)
4681 a->transport_return = PENDING_DEFER;
4683 continue_sequence++; /* for consistency */
4684 clearflag(sx->first_addr, af_new_conn);
4685 setflag(sx->first_addr, af_cont_conn); /* Causes * in logging */
4686 pipelining_active = sx->pipelining_used; /* was cleared at DATA */
4690 /* Unless caller said it already has more messages listed for this host,
4691 pass the connection on to a new Exim process (below, the call to
4692 transport_pass_socket). If the caller has more ready, just return with
4693 the connection still open. */
4696 if (tls_out.active.sock >= 0)
4697 if ( f.continue_more
4698 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4700 /* Before passing the socket on, or returning to caller with it still
4701 open, we must shut down TLS. Not all MTAs allow for the continuation
4702 of the SMTP session when TLS is shut down. We test for this by sending
4703 a new EHLO. If we don't get a good response, we don't attempt to pass
4705 NB: TLS close is *required* per RFC 9266 when tls-exporter info has
4706 been used, which we do under TLSv1.3 for the gsasl SCRAM*PLUS methods.
4707 But we were always doing it anyway. */
4709 tls_close(sx->cctx.tls_ctx,
4710 sx->send_tlsclose ? TLS_SHUTDOWN_WAIT : TLS_SHUTDOWN_WONLY);
4711 sx->send_tlsclose = FALSE;
4712 sx->cctx.tls_ctx = NULL;
4713 tls_out.active.sock = -1;
4714 smtp_peer_options = smtp_peer_options_wrap;
4716 && smtp_write_command(sx, SCMD_FLUSH, "EHLO %s\r\n", sx->helo_data)
4718 && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4719 '2', ob->command_timeout);
4721 if (sx->ok && f.continue_more)
4722 goto TIDYUP; /* More addresses for another run */
4726 /* Set up a pipe for proxying TLS for the new transport process */
4728 smtp_peer_options |= OPTION_TLS;
4729 if ((sx->ok = socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4732 set_errno(sx->first_addr, errno, US"internal allocation problem",
4734 # ifdef EXPERIMENTAL_DSN_INFO
4735 sx->smtp_greeting, sx->helo_response,
4737 &sx->delivery_start);
4741 if (f.continue_more)
4742 goto TIDYUP; /* More addresses for another run */
4744 /* If the socket is successfully passed, we mustn't send QUIT (or
4745 indeed anything!) from here. */
4747 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4748 propagate it from the initial
4750 if (sx->ok && transport_pass_socket(tblock->name, host->name,
4751 host->address, new_message_id, socket_fd
4752 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4753 , sx->peer_limit_mail, sx->peer_limit_rcpt, sx->peer_limit_rcptdom
4757 sx->send_quit = FALSE;
4759 /* We have passed the client socket to a fresh transport process.
4760 If TLS is still active, we need to proxy it for the transport we
4761 just passed the baton to. Fork a child to to do it, and return to
4762 get logging done asap. Which way to place the work makes assumptions
4763 about post-fork prioritisation which may not hold on all platforms. */
4765 if (tls_out.active.sock >= 0)
4767 int pid = exim_fork(US"tls-proxy-interproc");
4768 if (pid == 0) /* child; fork again to disconnect totally */
4770 /* does not return */
4771 smtp_proxy_tls(sx->cctx.tls_ctx, sx->buffer, sizeof(sx->buffer), pfd,
4772 ob->command_timeout, host->name);
4775 if (pid > 0) /* parent */
4778 /* tidy the inter-proc to disconn the proxy proc */
4779 waitpid(pid, NULL, 0);
4780 tls_close(sx->cctx.tls_ctx, TLS_NO_SHUTDOWN);
4781 sx->cctx.tls_ctx = NULL;
4782 (void)close(sx->cctx.sock);
4784 continue_transport = NULL;
4785 continue_hostname = NULL;
4788 log_write(0, LOG_PANIC_DIE, "fork failed");
4794 /* If RSET failed and there are addresses left, they get deferred. */
4796 set_errno(sx->first_addr, errno, msg, DEFER, FALSE, host,
4797 #ifdef EXPERIMENTAL_DSN_INFO
4798 sx->smtp_greeting, sx->helo_response,
4800 &sx->delivery_start);
4804 /* End off tidily with QUIT unless the connection has died or the socket has
4805 been passed to another process. */
4809 { /* Use _MORE to get QUIT in FIN segment */
4810 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4812 if (sx->cctx.tls_ctx && sx->send_tlsclose)
4814 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
4815 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4817 tls_shutdown_wr(sx->cctx.tls_ctx);
4818 sx->send_tlsclose = FALSE;
4825 /* Close the socket, and return the appropriate value, first setting
4826 works because the NULL setting is passed back to the calling process, and
4827 remote_max_parallel is forced to 1 when delivering over an existing connection,
4829 If all went well and continue_more is set, we shouldn't actually get here if
4830 there are further addresses, as the return above will be taken. However,
4831 writing RSET might have failed, or there may be other addresses whose hosts are
4832 specified in the transports, and therefore not visible at top level, in which
4833 case continue_more won't get set. */
4837 /* This flushes data queued in the socket, being the QUIT and any TLS Close,
4838 sending them along with the client FIN flag. Us (we hope) sending FIN first
4839 means we (client) take the TIME_WAIT state, so the server (which likely has a
4840 higher connection rate) does not have to. */
4842 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4843 shutdown(sx->cctx.sock, SHUT_WR);
4846 if (sx->send_quit || tcw_done && !tcw)
4848 /* Wait for (we hope) ack of our QUIT, and a server FIN. Discard any data
4849 received, then discard the socket. Any packet received after then, or receive
4850 data still in the socket, will get a RST - hence the pause/drain. */
4852 /* Reap the response to QUIT, timing out after one second */
4853 (void) smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', 1);
4855 if (sx->cctx.tls_ctx)
4859 /* Reap the TLS Close Notify from the server, timing out after one second */
4860 sigalrm_seen = FALSE;
4863 n = tls_read(sx->cctx.tls_ctx, sx->inbuffer, sizeof(sx->inbuffer));
4864 while (!sigalrm_seen && n > 0);
4867 if (sx->send_tlsclose)
4869 # ifdef EXIM_TCP_CORK
4870 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4872 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4875 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WONLY);
4876 sx->cctx.tls_ctx = NULL;
4880 /* Drain any trailing data from the socket before close, to avoid sending a RST */
4882 if ( poll_one_fd(sx->cctx.sock, POLLIN, 20) != 0 /* 20ms */
4883 && fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4884 for (int i = 16, n; /* drain socket */
4885 (n = read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer))) > 0 && i > 0;
4886 i--) HDEBUG(D_transport|D_acl|D_v)
4889 debug_printf_indent(" SMTP(drain %d bytes)<< %.*s\n", n, m, sx->inbuffer);
4890 for (m = 0; m < n; m++)
4891 debug_printf("0x%02x\n", sx->inbuffer[m]);
4894 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4895 (void)close(sx->cctx.sock);
4897 continue_transport = NULL;
4898 continue_hostname = NULL;
4899 smtp_debug_cmd_report();
4901 #ifndef DISABLE_EVENT
4902 (void) event_raise(tblock->event_action, US"tcp:close", NULL, NULL);
4908 sx->first_addr = NULL;
4909 for (address_item * a = sx->addrlist->next; a; a = a->next)
4910 if (a->transport_return == DANE)
4912 a->transport_return = PENDING_DEFER;
4913 if (!sx->first_addr)
4915 /* Remember the new start-point in the addrlist, for smtp_setup_conn()
4916 to get the domain string for SNI */
4919 clearflag(a, af_cont_conn);
4920 setflag(a, af_new_conn); /* clear * from logging */
4921 DEBUG(D_transport) debug_printf("DANE: go-around for %s\n", a->domain);
4924 continue_sequence = 1; /* for consistency */
4929 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4930 if (mail_limit && sx->first_addr)
4932 /* Reset the sequence count since we closed the connection. This is flagged
4933 on the pipe back to the delivery process so that a non-continued-conn delivery
4936 continue_sequence = 1; /* for consistency */
4937 clearflag(sx->first_addr, af_cont_conn);
4938 setflag(sx->first_addr, af_new_conn); /* clear * from logging */
4947 if (dane_held) for (address_item * a = sx->addrlist->next; a; a = a->next)
4948 if (a->transport_return == DANE)
4949 a->transport_return = PENDING_DEFER;
4957 /*************************************************
4958 * Closedown entry point *
4959 *************************************************/
4961 /* This function is called when exim is passed an open smtp channel
4962 from another incarnation, but the message which it has been asked
4963 to deliver no longer exists. The channel is on stdin.
4965 We might do fancy things like looking for another message to send down
4966 the channel, but if the one we sought has gone, it has probably been
4967 delivered by some other process that itself will seek further messages,
4968 so just close down our connection.
4970 Argument: pointer to the transport instance block
4975 smtp_transport_closedown(transport_instance *tblock)
4977 smtp_transport_options_block * ob = SOB tblock->options_block;
4978 client_conn_ctx cctx;
4979 smtp_context sx = {0};
4981 uschar inbuffer[4096];
4982 uschar outbuffer[16];
4984 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4985 cctx.sock = fileno(stdin);
4986 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4988 sx.inblock.cctx = &cctx;
4989 sx.inblock.buffer = inbuffer;
4990 sx.inblock.buffersize = sizeof(inbuffer);
4991 sx.inblock.ptr = inbuffer;
4992 sx.inblock.ptrend = inbuffer;
4994 sx.outblock.cctx = &cctx;
4995 sx.outblock.buffersize = sizeof(outbuffer);
4996 sx.outblock.buffer = outbuffer;
4997 sx.outblock.ptr = outbuffer;
4998 sx.outblock.cmd_count = 0;
4999 sx.outblock.authenticating = FALSE;
5001 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
5002 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
5003 (void)close(cctx.sock);
5008 /*************************************************
5009 * Prepare addresses for delivery *
5010 *************************************************/
5012 /* This function is called to flush out error settings from previous delivery
5013 attempts to other hosts. It also records whether we got here via an MX record
5014 or not in the more_errno field of the address. We are interested only in
5015 addresses that are still marked DEFER - others may have got delivered to a
5016 previously considered IP address. Set their status to PENDING_DEFER to indicate
5017 which ones are relevant this time.
5020 addrlist the list of addresses
5021 host the host we are delivering to
5023 Returns: the first address for this delivery
5026 static address_item *
5027 prepare_addresses(address_item *addrlist, host_item *host)
5029 address_item *first_addr = NULL;
5030 for (address_item * addr = addrlist; addr; addr = addr->next)
5031 if (addr->transport_return == DEFER)
5033 if (!first_addr) first_addr = addr;
5034 addr->transport_return = PENDING_DEFER;
5035 addr->basic_errno = 0;
5036 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
5037 addr->message = NULL;
5039 addr->cipher = NULL;
5040 addr->ourcert = NULL;
5041 addr->peercert = NULL;
5042 addr->peerdn = NULL;
5043 addr->ocsp = OCSP_NOT_REQ;
5044 addr->tlsver = NULL;
5046 #ifdef EXPERIMENTAL_DSN_INFO
5047 addr->smtp_greeting = NULL;
5048 addr->helo_response = NULL;
5056 /*************************************************
5057 * Main entry point *
5058 *************************************************/
5060 /* See local README for interface details. As this is a remote transport, it is
5061 given a chain of addresses to be delivered in one connection, if possible. It
5062 always returns TRUE, indicating that each address has its own independent
5063 status set, except if there is a setting up problem, in which case it returns
5067 smtp_transport_entry(
5068 transport_instance *tblock, /* data for this instantiation */
5069 address_item *addrlist) /* addresses we are working on */
5072 int hosts_defer = 0;
5074 int hosts_looked_up = 0;
5075 int hosts_retry = 0;
5076 int hosts_serial = 0;
5077 int hosts_total = 0;
5078 int total_hosts_tried = 0;
5079 BOOL expired = TRUE;
5080 uschar *expanded_hosts = NULL;
5082 uschar *tid = string_sprintf("%s transport", tblock->name);
5083 smtp_transport_options_block *ob = SOB tblock->options_block;
5084 host_item *hostlist = addrlist->host_list;
5085 host_item *host = NULL;
5089 debug_printf("%s transport entered\n", tblock->name);
5090 for (address_item * addr = addrlist; addr; addr = addr->next)
5091 debug_printf(" %s\n", addr->address);
5094 debug_printf("hostlist:\n");
5095 for (host_item * host = hostlist; host; host = host->next)
5096 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
5098 if (continue_hostname)
5099 debug_printf("already connected to %s [%s] (on fd %d)\n",
5100 continue_hostname, continue_host_address,
5101 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
5104 /* Check the restrictions on line length */
5106 if (max_received_linelength > ob->message_linelength_limit)
5109 gettimeofday(&now, NULL);
5111 for (address_item * addr = addrlist; addr; addr = addr->next)
5112 if (addr->transport_return == DEFER)
5113 addr->transport_return = PENDING_DEFER;
5115 set_errno_nohost(addrlist, ERRNO_SMTPFORMAT,
5116 US"message has lines too long for transport", FAIL, TRUE, &now);
5120 /* Set the flag requesting that these hosts be added to the waiting
5121 database if the delivery fails temporarily or if we are running with
5122 queue_smtp or a 2-stage queue run. This gets unset for certain
5123 kinds of error, typically those that are specific to the message. */
5125 update_waiting = TRUE;
5127 /* If a host list is not defined for the addresses - they must all have the
5128 same one in order to be passed to a single transport - or if the transport has
5129 a host list with hosts_override set, use the host list supplied with the
5130 transport. It is an error for this not to exist. */
5132 if (!hostlist || (ob->hosts_override && ob->hosts))
5136 addrlist->message = string_sprintf("%s transport called with no hosts set",
5138 addrlist->transport_return = PANIC;
5139 return FALSE; /* Only top address has status */
5142 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
5145 /* If the transport's host list contains no '$' characters, and we are not
5146 randomizing, it is fixed and therefore a chain of hosts can be built once
5147 and for all, and remembered for subsequent use by other calls to this
5148 transport. If, on the other hand, the host list does contain '$', or we are
5149 randomizing its order, we have to rebuild it each time. In the fixed case,
5150 as the hosts string will never be used again, it doesn't matter that we
5151 replace all the : characters with zeros. */
5155 uschar *s = ob->hosts;
5157 if (Ustrchr(s, '$'))
5159 if (!(expanded_hosts = expand_string(s)))
5161 addrlist->message = string_sprintf("failed to expand list of hosts "
5162 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
5163 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
5164 return FALSE; /* Only top address has status */
5166 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
5167 "\"%s\"\n", s, expanded_hosts);
5171 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
5175 log_write(0, LOG_MAIN|LOG_PANIC,
5176 "attempt to use tainted host list '%s' from '%s' in transport %s",
5177 s, ob->hosts, tblock->name);
5178 /* Avoid leaking info to an attacker */
5179 addrlist->message = US"internal configuration error";
5180 addrlist->transport_return = PANIC;
5184 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
5186 /* Check that the expansion yielded something useful. */
5190 string_sprintf("%s transport has empty hosts setting", tblock->name);
5191 addrlist->transport_return = PANIC;
5192 return FALSE; /* Only top address has status */
5195 /* If there was no expansion of hosts, save the host list for
5198 if (!expanded_hosts) ob->hostlist = hostlist;
5201 /* This is not the first time this transport has been run in this delivery;
5202 the host list was built previously. */
5205 hostlist = ob->hostlist;
5208 /* The host list was supplied with the address. If hosts_randomize is set, we
5209 must sort it into a random order if it did not come from MX records and has not
5210 already been randomized (but don't bother if continuing down an existing
5213 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
5215 host_item *newlist = NULL;
5218 host_item *h = hostlist;
5219 hostlist = hostlist->next;
5221 h->sort_key = random_number(100);
5228 else if (h->sort_key < newlist->sort_key)
5235 host_item *hh = newlist;
5238 if (h->sort_key < hh->next->sort_key) break;
5246 hostlist = addrlist->host_list = newlist;
5249 /* Sort out the default port. */
5251 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
5253 /* For each host-plus-IP-address on the list:
5255 . If this is a continued delivery and the host isn't the one with the
5256 current connection, skip.
5258 . If the status is unusable (i.e. previously failed or retry checked), skip.
5260 . If no IP address set, get the address, either by turning the name into
5261 an address, calling gethostbyname if gethostbyname is on, or by calling
5262 the DNS. The DNS may yield multiple addresses, in which case insert the
5263 extra ones into the list.
5265 . Get the retry data if not previously obtained for this address and set the
5266 field which remembers the state of this address. Skip if the retry time is
5267 not reached. If not, remember whether retry data was found. The retry string
5268 contains both the name and the IP address.
5270 . Scan the list of addresses and mark those whose status is DEFER as
5271 PENDING_DEFER. These are the only ones that will be processed in this cycle
5274 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
5275 Some addresses may be successfully delivered, others may fail, and yet
5276 others may get temporary errors and so get marked DEFER.
5278 . The return from the delivery attempt is OK if a connection was made and a
5279 valid SMTP dialogue was completed. Otherwise it is DEFER.
5281 . If OK, add a "remove" retry item for this host/IPaddress, if any.
5283 . If fail to connect, or other defer state, add a retry item.
5285 . If there are any addresses whose status is still DEFER, carry on to the
5286 next host/IPaddress, unless we have tried the number of hosts given
5287 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
5288 there is some fancy logic for hosts_max_try that means its limit can be
5289 overstepped in some circumstances.
5291 If we get to the end of the list, all hosts have deferred at least one address,
5292 or not reached their retry times. If delay_after_cutoff is unset, it requests a
5293 delivery attempt to those hosts whose last try was before the arrival time of
5294 the current message. To cope with this, we have to go round the loop a second
5295 time. After that, set the status and error data for any addresses that haven't
5296 had it set already. */
5298 for (int cutoff_retry = 0;
5299 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
5302 host_item *nexthost = NULL;
5303 int unexpired_hosts_tried = 0;
5304 BOOL continue_host_tried = FALSE;
5306 retry_non_continued:
5307 for (host = hostlist;
5309 && unexpired_hosts_tried < ob->hosts_max_try
5310 && total_hosts_tried < ob->hosts_max_try_hardlimit;
5315 BOOL host_is_expired = FALSE;
5316 BOOL message_defer = FALSE;
5317 BOOL some_deferred = FALSE;
5318 address_item *first_addr = NULL;
5319 uschar *interface = NULL;
5320 uschar *retry_host_key = NULL;
5321 uschar *retry_message_key = NULL;
5322 uschar *serialize_key = NULL;
5324 /* Deal slightly better with a possible Linux kernel bug that results
5325 in intermittent TFO-conn fails deep into the TCP flow. Bug 2907 tracks.
5326 Hack: Clear TFO option for any further hosts on this tpt run. */
5328 if (total_hosts_tried > 0)
5330 DEBUG(D_transport|D_acl|D_v)
5331 debug_printf("Clearing TFO as not first host for message\n");
5332 ob->hosts_try_fastopen = US"";
5335 /* Default next host is next host. :-) But this can vary if the
5336 hosts_max_try limit is hit (see below). It may also be reset if a host
5337 address is looked up here (in case the host was multihomed). */
5339 nexthost = host->next;
5341 /* If the address hasn't yet been obtained from the host name, look it up
5342 now, unless the host is already marked as unusable. If it is marked as
5343 unusable, it means that the router was unable to find its IP address (in
5344 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
5345 the lookup failed last time. We don't get this far if *all* MX records
5346 point to non-existent hosts; that is treated as a hard error.
5348 We can just skip this host entirely. When the hosts came from the router,
5349 the address will timeout based on the other host(s); when the address is
5350 looked up below, there is an explicit retry record added.
5352 Note that we mustn't skip unusable hosts if the address is not unset; they
5353 may be needed as expired hosts on the 2nd time round the cutoff loop. */
5357 int new_port, flags;
5359 if (host->status >= hstatus_unusable)
5361 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
5366 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
5368 /* The host name is permitted to have an attached port. Find it, and
5369 strip it from the name. Just remember it for now. */
5371 new_port = host_item_get_port(host);
5373 /* Count hosts looked up */
5377 /* Find by name if so configured, or if it's an IP address. We don't
5378 just copy the IP address, because we need the test-for-local to happen. */
5380 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
5381 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
5382 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
5384 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
5385 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
5387 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
5388 &ob->dnssec, /* domains for request/require */
5391 /* Update the host (and any additional blocks, resulting from
5392 multihoming) with a host-specific port, if any. */
5394 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
5396 /* Failure to find the host at this time (usually DNS temporary failure)
5397 is really a kind of routing failure rather than a transport failure.
5398 Therefore we add a retry item of the routing kind, not to stop us trying
5399 to look this name up here again, but to ensure the address gets timed
5400 out if the failures go on long enough. A complete failure at this point
5401 commonly points to a configuration error, but the best action is still
5402 to carry on for the next host. */
5404 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
5406 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
5408 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
5409 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
5410 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
5411 host->status = hstatus_unusable;
5413 for (address_item * addr = addrlist; addr; addr = addr->next)
5415 if (addr->transport_return != DEFER) continue;
5416 addr->basic_errno = ERRNO_UNKNOWNHOST;
5417 addr->message = string_sprintf(
5418 rc == HOST_FIND_SECURITY
5419 ? "lookup of IP address for %s was insecure"
5420 : "failed to lookup IP address for %s",
5426 /* If the host is actually the local host, we may have a problem, or
5427 there may be some cunning configuration going on. In the problem case,
5428 log things and give up. The default transport status is already DEFER. */
5430 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
5432 for (address_item * addr = addrlist; addr; addr = addr->next)
5434 addr->basic_errno = ERRNO_HOST_IS_LOCAL;
5435 addr->message = string_sprintf("%s transport found host %s to be "
5436 "local", tblock->name, host->name);
5440 } /* End of block for IP address lookup */
5442 /* If this is a continued delivery, we are interested only in the host
5443 which matches the name of the existing open channel. The check is put
5444 here after the local host lookup, in case the name gets expanded as a
5445 result of the lookup. Set expired FALSE, to save the outer loop executing
5448 if (continue_hostname)
5449 if ( Ustrcmp(continue_hostname, host->name) != 0
5450 || Ustrcmp(continue_host_address, host->address) != 0
5454 continue; /* With next host */
5457 continue_host_tried = TRUE;
5459 /* Reset the default next host in case a multihomed host whose addresses
5460 are not looked up till just above added to the host list. */
5462 nexthost = host->next;
5464 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
5465 domain is in queue_smtp_domains, we don't actually want to attempt any
5466 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
5467 there is a lookup defer in queue_smtp_domains, proceed as if the domain
5468 were not in it. We don't want to hold up all SMTP deliveries! Except when
5469 doing a two-stage queue run, don't do this if forcing. */
5471 if ( (!f.deliver_force || f.queue_2stage)
5473 || match_isinlist(addrlist->domain,
5474 CUSS &queue_smtp_domains, 0,
5475 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK)
5478 DEBUG(D_transport) debug_printf("first-pass routing only\n");
5480 for (address_item * addr = addrlist; addr; addr = addr->next)
5481 if (addr->transport_return == DEFER)
5482 addr->message = US"first-pass only routing due to -odqs, "
5483 "queue_smtp_domains or control=queue";
5484 continue; /* With next host */
5487 /* Count hosts being considered - purely for an intelligent comment
5488 if none are usable. */
5492 /* Set $host and $host address now in case they are needed for the
5493 interface expansion or the serialize_hosts check; they remain set if an
5494 actual delivery happens. */
5496 deliver_host = host->name;
5497 deliver_host_address = host->address;
5498 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
5499 : host->dnssec == DS_NO ? US"no"
5502 /* Set up a string for adding to the retry key if the port number is not
5503 the standard SMTP port. A host may have its own port setting that overrides
5506 pistring = string_sprintf(":%d", host->port == PORT_NONE
5507 ? defport : host->port);
5508 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
5510 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
5511 string is set, even if constant (as different transports can have different
5512 constant settings), we must add it to the key that is used for retries,
5513 because connections to the same host from a different interface should be
5514 treated separately. */
5516 host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
5518 uschar * s = ob->interface;
5521 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
5523 pistring = string_sprintf("%s/%s", pistring, interface);
5527 /* The first time round the outer loop, check the status of the host by
5528 inspecting the retry data. The second time round, we are interested only
5529 in expired hosts that haven't been tried since this message arrived. */
5531 if (cutoff_retry == 0)
5534 /* Ensure the status of the address is set by checking retry data if
5535 necessary. There may be host-specific retry data (applicable to all
5536 messages) and also data for retries of a specific message at this host.
5537 If either of these retry records are actually read, the keys used are
5538 returned to save recomputing them later. */
5540 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5541 US"retry_include_ip_address", ob->retry_include_ip_address,
5542 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5543 continue; /* with next host */
5545 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
5546 incl_ip, &retry_host_key, &retry_message_key);
5548 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
5549 host->address ? host->address : US"", pistring,
5550 host->status == hstatus_usable ? "usable"
5551 : host->status == hstatus_unusable ? "unusable"
5552 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
5554 /* Skip this address if not usable at this time, noting if it wasn't
5555 actually expired, both locally and in the address. */
5557 switch (host->status)
5559 case hstatus_unusable:
5561 setflag(addrlist, af_retry_skipped);
5564 case hstatus_unusable_expired:
5567 case hwhy_retry: hosts_retry++; break;
5568 case hwhy_failed: hosts_fail++; break;
5570 case hwhy_deferred: hosts_defer++; break;
5573 /* If there was a retry message key, implying that previously there
5574 was a message-specific defer, we don't want to update the list of
5575 messages waiting for these hosts. */
5577 if (retry_message_key) update_waiting = FALSE;
5578 continue; /* With the next host or IP address */
5582 /* Second time round the loop: if the address is set but expired, and
5583 the message is newer than the last try, let it through. */
5588 || host->status != hstatus_unusable_expired
5589 || host->last_try > received_time.tv_sec)
5591 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
5592 host->name, host->address, pistring);
5593 host_is_expired = TRUE;
5596 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
5597 it remains TRUE only if all hosts are expired and none are actually tried.
5602 /* If this host is listed as one to which access must be serialized,
5603 see if another Exim process has a connection to it, and if so, skip
5604 this host. If not, update the database to record our connection to it
5605 and remember this for later deletion. Do not do any of this if we are
5606 sending the message down a pre-existing connection. */
5608 if ( !continue_hostname
5609 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
5611 serialize_key = string_sprintf("host-serialize-%s", host->name);
5612 if (!enq_start(serialize_key, 1))
5615 debug_printf("skipping host %s because another Exim process "
5616 "is connected to it\n", host->name);
5622 /* OK, we have an IP address that is not waiting for its retry time to
5623 arrive (it might be expired) OR (second time round the loop) we have an
5624 expired host that hasn't been tried since the message arrived. Have a go
5625 at delivering the message to it. First prepare the addresses by flushing
5626 out the result of previous attempts, and finding the first address that
5627 is still to be delivered. */
5629 first_addr = prepare_addresses(addrlist, host);
5631 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5632 message_id, host->name, host->address, addrlist->address,
5633 addrlist->next ? ", ..." : "");
5635 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5636 message_id, host->name, host->address, pistring, addrlist->address,
5637 addrlist->next ? ", ..." : "");
5639 /* This is not for real; don't do the delivery. If there are
5640 any remaining hosts, list them. */
5645 gettimeofday(&now, NULL);
5646 set_errno_nohost(addrlist, 0, NULL, OK, FALSE, &now);
5647 for (address_item * addr = addrlist; addr; addr = addr->next)
5649 addr->host_used = host;
5650 addr->special_action = '*';
5651 addr->message = US"delivery bypassed by -N option";
5655 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5656 "*** host and remaining hosts:\n", tblock->name);
5657 for (host_item * host2 = host; host2; host2 = host2->next)
5658 debug_printf(" %s [%s]\n", host2->name,
5659 host2->address ? host2->address : US"unset");
5664 /* This is for real. If the host is expired, we don't count it for
5665 hosts_max_retry. This ensures that all hosts must expire before an address
5666 is timed out, unless hosts_max_try_hardlimit (which protects against
5667 lunatic DNS configurations) is reached.
5669 If the host is not expired and we are about to hit the hosts_max_retry
5670 limit, check to see if there is a subsequent hosts with a different MX
5671 value. If so, make that the next host, and don't count this one. This is a
5672 heuristic to make sure that different MXs do get tried. With a normal kind
5673 of retry rule, they would get tried anyway when the earlier hosts were
5674 delayed, but if the domain has a "retry every time" type of rule - as is
5675 often used for the the very large ISPs, that won't happen. */
5680 /* Make a copy of the host if it is local to this invocation
5681 of the transport. */
5685 thost = store_get(sizeof(host_item), GET_UNTAINTED);
5687 thost->name = string_copy(host->name);
5688 thost->address = string_copy(host->address);
5693 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5696 debug_printf("hosts_max_try limit reached with this host\n");
5697 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5700 unexpired_hosts_tried--;
5701 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5702 "and will be tried\n");
5707 /* Attempt the delivery. */
5709 total_hosts_tried++;
5710 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5711 &message_defer, FALSE);
5714 OK => connection made, each address contains its result;
5715 message_defer is set for message-specific defers (when all
5716 recipients are marked defer)
5717 DEFER => there was a non-message-specific delivery problem;
5718 ERROR => there was a problem setting up the arguments for a filter,
5719 or there was a problem with expanding added headers
5722 /* If the result is not OK, there was a non-message-specific problem.
5723 If the result is DEFER, we need to write to the logs saying what happened
5724 for this particular host, except in the case of authentication and TLS
5725 failures, where the log has already been written. If all hosts defer a
5726 general message is written at the end. */
5728 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5729 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5730 write_logs(host, first_addr->message, first_addr->basic_errno);
5732 #ifndef DISABLE_EVENT
5734 deferred_event_raise(first_addr, host, US"msg:host:defer");
5737 /* If STARTTLS was accepted, but there was a failure in setting up the
5738 TLS session (usually a certificate screwup), and the host is not in
5739 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5740 TLS forcibly turned off. We have to start from scratch with a new SMTP
5741 connection. That's why the retry is done from here, not from within
5742 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5743 session, so the in-clear transmission after those errors, if permitted,
5744 happens inside smtp_deliver().] */
5748 && first_addr->basic_errno == ERRNO_TLSFAILURE
5749 && ob->tls_tempfail_tryclear
5750 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5753 log_write(0, LOG_MAIN,
5754 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5755 first_addr->message, host->name, host->address);
5756 first_addr = prepare_addresses(addrlist, host);
5757 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5758 &message_defer, TRUE);
5759 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5760 write_logs(host, first_addr->message, first_addr->basic_errno);
5761 # ifndef DISABLE_EVENT
5763 deferred_event_raise(first_addr, host, US"msg:host:defer");
5766 #endif /*DISABLE_TLS*/
5768 #ifndef DISABLE_EVENT
5769 /* If the last host gave a defer raise a per-message event */
5772 && unexpired_hosts_tried < ob->hosts_max_try
5773 && total_hosts_tried < ob->hosts_max_try_hardlimit
5775 && (message_defer || rc == DEFER)
5777 deferred_event_raise(first_addr, host, US"msg:defer");
5781 /* Delivery attempt finished */
5783 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5784 message_id, host->name, host->address, pistring, addrlist->address,
5785 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5787 /* Release serialization if set up */
5789 if (serialize_key) enq_end(serialize_key);
5791 /* If the result is DEFER, or if a host retry record is known to exist, we
5792 need to add an item to the retry chain for updating the retry database
5793 at the end of delivery. We only need to add the item to the top address,
5794 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5795 for any other delivery attempts using the same address. (It is copied into
5796 the unusable tree at the outer level, so even if different address blocks
5797 contain the same address, it still won't get tried again.) */
5799 if (rc == DEFER || retry_host_key)
5801 int delete_flag = rc != DEFER ? rf_delete : 0;
5802 if (!retry_host_key)
5805 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5806 US"retry_include_ip_address", ob->retry_include_ip_address,
5807 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5808 incl_ip = TRUE; /* error; use most-specific retry record */
5810 retry_host_key = incl_ip
5811 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5812 : string_sprintf("T:%S%s", host->name, pistring);
5815 /* If a delivery of another message over an existing SMTP connection
5816 yields DEFER, we do NOT set up retry data for the host. This covers the
5817 case when there are delays in routing the addresses in the second message
5818 that are so long that the server times out. This is alleviated by not
5819 routing addresses that previously had routing defers when handling an
5820 existing connection, but even so, this case may occur (e.g. if a
5821 previously happily routed address starts giving routing defers). If the
5822 host is genuinely down, another non-continued message delivery will
5823 notice it soon enough. */
5825 if (delete_flag != 0 || !continue_hostname)
5826 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5828 /* We may have tried an expired host, if its retry time has come; ensure
5829 the status reflects the expiry for the benefit of any other addresses. */
5833 host->status = host_is_expired
5834 ? hstatus_unusable_expired : hstatus_unusable;
5835 host->why = hwhy_deferred;
5839 /* If message_defer is set (host was OK, but every recipient got deferred
5840 because of some message-specific problem), or if that had happened
5841 previously so that a message retry key exists, add an appropriate item
5842 to the retry chain. Note that if there was a message defer but now there is
5843 a host defer, the message defer record gets deleted. That seems perfectly
5844 reasonable. Also, stop the message from being remembered as waiting
5845 for specific hosts. */
5847 if (message_defer || retry_message_key)
5849 int delete_flag = message_defer ? 0 : rf_delete;
5850 if (!retry_message_key)
5853 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5854 US"retry_include_ip_address", ob->retry_include_ip_address,
5855 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5856 incl_ip = TRUE; /* error; use most-specific retry record */
5858 retry_message_key = incl_ip
5859 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5861 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5863 retry_add_item(addrlist, retry_message_key,
5864 rf_message | rf_host | delete_flag);
5865 update_waiting = FALSE;
5868 /* Any return other than DEFER (that is, OK or ERROR) means that the
5869 addresses have got their final statuses filled in for this host. In the OK
5870 case, see if any of them are deferred. */
5873 for (address_item * addr = addrlist; addr; addr = addr->next)
5874 if (addr->transport_return == DEFER)
5876 some_deferred = TRUE;
5880 /* If no addresses deferred or the result was ERROR, return. We do this for
5881 ERROR because a failing filter set-up or add_headers expansion is likely to
5882 fail for any host we try. */
5884 if (rc == ERROR || (rc == OK && !some_deferred))
5886 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5887 return TRUE; /* Each address has its status */
5890 /* If the result was DEFER or some individual addresses deferred, let
5891 the loop run to try other hosts with the deferred addresses, except for the
5892 case when we were trying to deliver down an existing channel and failed.
5893 Don't try any other hosts in this case. */
5895 if (continue_hostname) break;
5897 /* If the whole delivery, or some individual addresses, were deferred and
5898 there are more hosts that could be tried, do not count this host towards
5899 the hosts_max_try limit if the age of the message is greater than the
5900 maximum retry time for this host. This means we may try try all hosts,
5901 ignoring the limit, when messages have been around for some time. This is
5902 important because if we don't try all hosts, the address will never time
5903 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5905 if ((rc == DEFER || some_deferred) && nexthost)
5908 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5910 if (retry && retry->rules)
5912 retry_rule *last_rule;
5913 for (last_rule = retry->rules;
5915 last_rule = last_rule->next);
5916 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5918 else timedout = TRUE; /* No rule => timed out */
5922 unexpired_hosts_tried--;
5923 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5924 "hosts_max_try (message older than host's retry time)\n");
5930 if (unexpired_hosts_tried >= ob->hosts_max_try)
5931 debug_printf("reached transport hosts_max_try limit %d\n",
5933 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5934 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5935 ob->hosts_max_try_hardlimit);
5938 testharness_pause_ms(500); /* let server debug out */
5939 } /* End of loop for trying multiple hosts. */
5941 /* If we failed to find a matching host in the list, for an already-open
5942 connection, just close it and start over with the list. This can happen
5943 for routing that changes from run to run, or big multi-IP sites with
5946 if (continue_hostname && !continue_host_tried)
5948 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5950 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5952 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5954 /*XXX doublecheck that! */
5956 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5958 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5959 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5960 cutthrough.cctx.tls_ctx = NULL;
5961 cutthrough.is_tls = FALSE;
5965 (void) write(fd, US"QUIT\r\n", 6);
5968 cutthrough.cctx.sock = -1;
5969 continue_hostname = NULL;
5970 goto retry_non_continued;
5973 /* This is the end of the loop that repeats iff expired is TRUE and
5974 ob->delay_after_cutoff is FALSE. The second time round we will
5975 try those hosts that haven't been tried since the message arrived. */
5979 debug_printf("all IP addresses skipped or deferred at least one address\n");
5980 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5981 debug_printf("retrying IP addresses not tried since message arrived\n");
5986 /* Get here if all IP addresses are skipped or defer at least one address. In
5987 MUA wrapper mode, this will happen only for connection or other non-message-
5988 specific failures. Force the delivery status for all addresses to FAIL. */
5992 for (address_item * addr = addrlist; addr; addr = addr->next)
5993 addr->transport_return = FAIL;
5997 /* In the normal, non-wrapper case, add a standard message to each deferred
5998 address if there hasn't been an error, that is, if it hasn't actually been
5999 tried this time. The variable "expired" will be FALSE if any deliveries were
6000 actually tried, or if there was at least one host that was not expired. That
6001 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
6002 a delivery has been tried, an error code will be set, and the failing of the
6003 message is handled by the retry code later.
6005 If queue_smtp is set, or this transport was called to send a subsequent message
6006 down an existing TCP/IP connection, and something caused the host not to be
6007 found, we end up here, but can detect these cases and handle them specially. */
6009 for (address_item * addr = addrlist; addr; addr = addr->next)
6011 /* If host is not NULL, it means that we stopped processing the host list
6012 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
6013 means we need to behave as if some hosts were skipped because their retry
6014 time had not come. Specifically, this prevents the address from timing out.
6015 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
6016 hosts were tried. */
6019 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
6022 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
6023 "hosts were tried\n");
6028 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
6029 setflag(addr, af_retry_skipped);
6032 if (f.queue_smtp) /* no deliveries attempted */
6034 addr->transport_return = DEFER;
6035 addr->basic_errno = 0;
6036 addr->message = US"SMTP delivery explicitly queued";
6039 else if ( addr->transport_return == DEFER
6040 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
6044 addr->basic_errno = ERRNO_HRETRY;
6045 if (continue_hostname)
6046 addr->message = US"no host found for existing SMTP connection";
6049 setflag(addr, af_pass_message); /* This is not a security risk */
6050 addr->message = string_sprintf(
6051 "all hosts%s have been failing for a long time %s",
6052 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
6053 ob->delay_after_cutoff
6054 ? US"(and retry time not reached)"
6055 : US"and were last tried after this message arrived");
6057 /* If we are already using fallback hosts, or there are no fallback hosts
6058 defined, convert the result to FAIL to cause a bounce. */
6060 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
6061 addr->transport_return = FAIL;
6066 if (hosts_retry == hosts_total)
6067 s = "retry time not reached for any host%s";
6068 else if (hosts_fail == hosts_total)
6069 s = "all host address lookups%s failed permanently";
6070 else if (hosts_defer == hosts_total)
6071 s = "all host address lookups%s failed temporarily";
6072 else if (hosts_serial == hosts_total)
6073 s = "connection limit reached for all hosts%s";
6074 else if (hosts_fail+hosts_defer == hosts_total)
6075 s = "all host address lookups%s failed";
6077 s = "some host address lookups failed and retry time "
6078 "not reached for other hosts or connection limit reached%s";
6080 addr->message = string_sprintf(s,
6081 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
6086 /* Update the database which keeps information about which messages are waiting
6087 for which hosts to become available. For some message-specific errors, the
6088 update_waiting flag is turned off because we don't want follow-on deliveries in
6089 those cases. If this transport instance is explicitly limited to one message
6090 per connection then follow-on deliveries are not possible and there's no need
6091 to create/update the per-transport wait-<transport_name> database. */
6093 if (update_waiting && tblock->connection_max_messages != 1)
6094 transport_update_waiting(hostlist, tblock->name);
6098 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
6100 return TRUE; /* Each address has its status */
6103 #endif /*!MACRO_PREDEF*/
6106 /* End of transport/smtp.c */