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. */
12 #if defined(SUPPORT_DANE) && defined(DISABLE_TLS)
13 # error TLS is required for DANE
17 /* Options specific to the smtp transport. This transport also supports LMTP
18 over TCP/IP. The options must be in alphabetic order (note that "_" comes
19 before the lower case letters). Some live in the transport_instance block so as
20 to be publicly visible; these are flagged with opt_public. */
22 #define LOFF(field) OPT_OFF(smtp_transport_options_block, field)
24 optionlist smtp_transport_options[] = {
25 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
26 OPT_OFF(transport_instance, expand_multi_domain) },
27 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
28 LOFF(expand_retry_include_ip_address) },
30 { "address_retry_include_sender", opt_bool,
31 LOFF(address_retry_include_sender) },
32 { "allow_localhost", opt_bool, LOFF(allow_localhost) },
33 #ifdef EXPERIMENTAL_ARC
34 { "arc_sign", opt_stringptr, LOFF(arc_sign) },
36 { "authenticated_sender", opt_stringptr, LOFF(authenticated_sender) },
37 { "authenticated_sender_force", opt_bool, LOFF(authenticated_sender_force) },
38 { "command_timeout", opt_time, LOFF(command_timeout) },
39 { "connect_timeout", opt_time, LOFF(connect_timeout) },
40 { "connection_max_messages", opt_int | opt_public,
41 OPT_OFF(transport_instance, connection_max_messages) },
43 { "dane_require_tls_ciphers", opt_stringptr, LOFF(dane_require_tls_ciphers) },
45 { "data_timeout", opt_time, LOFF(data_timeout) },
46 { "delay_after_cutoff", opt_bool, LOFF(delay_after_cutoff) },
48 { "dkim_canon", opt_stringptr, LOFF(dkim.dkim_canon) },
49 { "dkim_domain", opt_stringptr, LOFF(dkim.dkim_domain) },
50 { "dkim_hash", opt_stringptr, LOFF(dkim.dkim_hash) },
51 { "dkim_identity", opt_stringptr, LOFF(dkim.dkim_identity) },
52 { "dkim_private_key", opt_stringptr, LOFF(dkim.dkim_private_key) },
53 { "dkim_selector", opt_stringptr, LOFF(dkim.dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr, LOFF(dkim.dkim_sign_headers) },
55 { "dkim_strict", opt_stringptr, LOFF(dkim.dkim_strict) },
56 { "dkim_timestamps", opt_stringptr, LOFF(dkim.dkim_timestamps) },
58 { "dns_qualify_single", opt_bool, LOFF(dns_qualify_single) },
59 { "dns_search_parents", opt_bool, LOFF(dns_search_parents) },
60 { "dnssec_request_domains", opt_stringptr, LOFF(dnssec.request) },
61 { "dnssec_require_domains", opt_stringptr, LOFF(dnssec.require) },
62 { "dscp", opt_stringptr, LOFF(dscp) },
63 { "fallback_hosts", opt_stringptr, LOFF(fallback_hosts) },
64 { "final_timeout", opt_time, LOFF(final_timeout) },
65 { "gethostbyname", opt_bool, LOFF(gethostbyname) },
66 { "helo_data", opt_stringptr, LOFF(helo_data) },
67 #if !defined(DISABLE_TLS) && !defined(DISABLE_TLS_RESUME)
68 { "host_name_extract", opt_stringptr, LOFF(host_name_extract) },
70 { "hosts", opt_stringptr, LOFF(hosts) },
71 { "hosts_avoid_esmtp", opt_stringptr, LOFF(hosts_avoid_esmtp) },
72 { "hosts_avoid_pipelining", opt_stringptr, LOFF(hosts_avoid_pipelining) },
74 { "hosts_avoid_tls", opt_stringptr, LOFF(hosts_avoid_tls) },
76 { "hosts_max_try", opt_int, LOFF(hosts_max_try) },
77 { "hosts_max_try_hardlimit", opt_int, LOFF(hosts_max_try_hardlimit) },
79 { "hosts_nopass_tls", opt_stringptr, LOFF(hosts_nopass_tls) },
80 { "hosts_noproxy_tls", opt_stringptr, LOFF(hosts_noproxy_tls) },
82 { "hosts_override", opt_bool, LOFF(hosts_override) },
83 #ifndef DISABLE_PIPE_CONNECT
84 { "hosts_pipe_connect", opt_stringptr, LOFF(hosts_pipe_connect) },
86 { "hosts_randomize", opt_bool, LOFF(hosts_randomize) },
87 #if !defined(DISABLE_TLS) && !defined(DISABLE_OCSP)
88 { "hosts_request_ocsp", opt_stringptr, LOFF(hosts_request_ocsp) },
90 { "hosts_require_alpn", opt_stringptr, LOFF(hosts_require_alpn) },
91 { "hosts_require_auth", opt_stringptr, LOFF(hosts_require_auth) },
94 { "hosts_require_dane", opt_stringptr, LOFF(hosts_require_dane) },
97 { "hosts_require_ocsp", opt_stringptr, LOFF(hosts_require_ocsp) },
99 { "hosts_require_tls", opt_stringptr, LOFF(hosts_require_tls) },
101 { "hosts_try_auth", opt_stringptr, LOFF(hosts_try_auth) },
102 { "hosts_try_chunking", opt_stringptr, LOFF(hosts_try_chunking) },
104 { "hosts_try_dane", opt_stringptr, LOFF(hosts_try_dane) },
106 { "hosts_try_fastopen", opt_stringptr, LOFF(hosts_try_fastopen) },
108 { "hosts_try_prdr", opt_stringptr, LOFF(hosts_try_prdr) },
111 { "hosts_verify_avoid_tls", opt_stringptr, LOFF(hosts_verify_avoid_tls) },
113 { "interface", opt_stringptr, LOFF(interface) },
114 { "keepalive", opt_bool, LOFF(keepalive) },
115 { "lmtp_ignore_quota", opt_bool, LOFF(lmtp_ignore_quota) },
116 { "max_rcpt", opt_int | opt_public,
117 OPT_OFF(transport_instance, max_addresses) },
118 { "message_linelength_limit", opt_int, LOFF(message_linelength_limit) },
119 { "multi_domain", opt_expand_bool | opt_public,
120 OPT_OFF(transport_instance, multi_domain) },
121 { "port", opt_stringptr, LOFF(port) },
122 { "protocol", opt_stringptr, LOFF(protocol) },
123 { "retry_include_ip_address", opt_expand_bool, LOFF(retry_include_ip_address) },
124 { "serialize_hosts", opt_stringptr, LOFF(serialize_hosts) },
125 { "size_addition", opt_int, LOFF(size_addition) },
127 { "socks_proxy", opt_stringptr, LOFF(socks_proxy) },
130 { "tls_alpn", opt_stringptr, LOFF(tls_alpn) },
131 { "tls_certificate", opt_stringptr, LOFF(tls_certificate) },
132 { "tls_crl", opt_stringptr, LOFF(tls_crl) },
133 { "tls_dh_min_bits", opt_int, LOFF(tls_dh_min_bits) },
134 { "tls_privatekey", opt_stringptr, LOFF(tls_privatekey) },
135 { "tls_require_ciphers", opt_stringptr, LOFF(tls_require_ciphers) },
136 # ifndef DISABLE_TLS_RESUME
137 { "tls_resumption_hosts", opt_stringptr, LOFF(tls_resumption_hosts) },
139 { "tls_sni", opt_stringptr, LOFF(tls_sni) },
140 { "tls_tempfail_tryclear", opt_bool, LOFF(tls_tempfail_tryclear) },
141 { "tls_try_verify_hosts", opt_stringptr, LOFF(tls_try_verify_hosts) },
142 { "tls_verify_cert_hostnames", opt_stringptr, LOFF(tls_verify_cert_hostnames)},
143 { "tls_verify_certificates", opt_stringptr, LOFF(tls_verify_certificates) },
144 { "tls_verify_hosts", opt_stringptr, LOFF(tls_verify_hosts) },
147 { "utf8_downconvert", opt_stringptr, LOFF(utf8_downconvert) },
151 /* Size of the options list. An extern variable has to be used so that its
152 address can appear in the tables drtables.c. */
154 int smtp_transport_options_count = nelem(smtp_transport_options);
160 smtp_transport_options_block smtp_transport_option_defaults = {0};
161 void smtp_transport_init(transport_instance *tblock) {}
162 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
163 void smtp_transport_closedown(transport_instance *tblock) {}
165 #else /*!MACRO_PREDEF*/
168 /* Default private options block for the smtp transport. */
170 smtp_transport_options_block smtp_transport_option_defaults = {
171 /* All non-mentioned elements 0/NULL/FALSE */
172 .helo_data = US"$primary_hostname",
173 .protocol = US"smtp",
174 .hosts_try_chunking = US"*",
176 .hosts_try_dane = US"*",
178 .hosts_try_fastopen = US"*",
180 .hosts_try_prdr = US"*",
183 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
185 .command_timeout = 5*60,
186 .connect_timeout = 5*60,
187 .data_timeout = 5*60,
188 .final_timeout = 10*60,
189 .size_addition = 1024,
191 .hosts_max_try_hardlimit = 50,
192 .message_linelength_limit = 998,
193 .address_retry_include_sender = TRUE,
194 .dns_qualify_single = TRUE,
195 .dnssec = { .request= US"*", .require=NULL },
196 .delay_after_cutoff = TRUE,
198 .retry_include_ip_address = TRUE,
200 .tls_verify_certificates = US"system",
201 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
202 .tls_tempfail_tryclear = TRUE,
203 .tls_try_verify_hosts = US"*",
204 .tls_verify_cert_hostnames = US"*",
205 # ifndef DISABLE_TLS_RESUME
206 .host_name_extract = US"${if and {{match{$host}{.outlook.com\\$}} {match{$item}{\\N^250-([\\w.]+)\\s\\N}}} {$1}}",
210 .utf8_downconvert = US"-1",
214 { .dkim_hash = US"sha256", },
218 /* some DSN flags for use later */
220 static int rf_list[] = {rf_notify_never, rf_notify_success,
221 rf_notify_failure, rf_notify_delay };
223 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
229 static uschar *smtp_command; /* Points to last cmd for error messages */
230 static uschar *mail_command; /* Points to MAIL cmd for error messages */
231 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
232 static BOOL update_waiting; /* TRUE to update the "wait" database */
234 /*XXX move to smtp_context */
235 static BOOL pipelining_active; /* current transaction is in pipe mode */
238 static unsigned ehlo_response(uschar * buf, unsigned checks);
241 /******************************************************************************/
244 smtp_deliver_init(void)
248 const pcre2_code ** re;
249 const uschar * string;
252 { ®ex_AUTH, AUTHS_REGEX },
253 { ®ex_CHUNKING, US"\\n250[\\s\\-]CHUNKING(\\s|\\n|$)" },
254 { ®ex_DSN, US"\\n250[\\s\\-]DSN(\\s|\\n|$)" },
255 { ®ex_IGNOREQUOTA, US"\\n250[\\s\\-]IGNOREQUOTA(\\s|\\n|$)" },
256 { ®ex_PIPELINING, US"\\n250[\\s\\-]PIPELINING(\\s|\\n|$)" },
257 { ®ex_SIZE, US"\\n250[\\s\\-]SIZE(\\s|\\n|$)" },
260 { ®ex_STARTTLS, US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)" },
263 { ®ex_PRDR, US"\\n250[\\s\\-]PRDR(\\s|\\n|$)" },
266 { ®ex_UTF8, US"\\n250[\\s\\-]SMTPUTF8(\\s|\\n|$)" },
268 #ifndef DISABLE_PIPE_CONNECT
269 { ®ex_EARLY_PIPE, US"\\n250[\\s\\-]" EARLY_PIPE_FEATURE_NAME "(\\s|\\n|$)" },
271 #ifdef EXPERIMENTAL_ESMTP_LIMITS
272 { ®ex_LIMITS, US"\\n250[\\s\\-]LIMITS\\s" },
276 for (struct list * l = list; l < list + nelem(list); l++)
278 *l->re = regex_must_compile(l->string, MCS_NOFLAGS, TRUE);
282 /*************************************************
283 * Setup entry point *
284 *************************************************/
286 /* This function is called when the transport is about to be used,
287 but before running it in a sub-process. It is used for two things:
289 (1) To set the fallback host list in addresses, when delivering.
290 (2) To pass back the interface, port, protocol, and other options, for use
291 during callout verification.
294 tblock pointer to the transport instance block
295 addrlist list of addresses about to be transported
296 tf if not NULL, pointer to block in which to return options
297 uid the uid that will be set (not used)
298 gid the gid that will be set (not used)
299 errmsg place for error message (not used)
301 Returns: OK always (FAIL, DEFER not used)
305 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
306 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
308 smtp_transport_options_block *ob = SOB tblock->options_block;
310 /* Pass back options if required. This interface is getting very messy. */
314 tf->interface = ob->interface;
316 tf->protocol = ob->protocol;
317 tf->hosts = ob->hosts;
318 tf->hosts_override = ob->hosts_override;
319 tf->hosts_randomize = ob->hosts_randomize;
320 tf->gethostbyname = ob->gethostbyname;
321 tf->qualify_single = ob->dns_qualify_single;
322 tf->search_parents = ob->dns_search_parents;
323 tf->helo_data = ob->helo_data;
326 /* Set the fallback host list for all the addresses that don't have fallback
327 host lists, provided that the local host wasn't present in the original host
330 if (!testflag(addrlist, af_local_host_removed))
331 for (; addrlist; addrlist = addrlist->next)
332 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
339 /*************************************************
340 * Initialization entry point *
341 *************************************************/
343 /* Called for each instance, after its options have been read, to
344 enable consistency checks to be done, or anything else that needs
347 Argument: pointer to the transport instance block
352 smtp_transport_init(transport_instance *tblock)
354 smtp_transport_options_block *ob = SOB tblock->options_block;
355 int old_pool = store_pool;
357 /* Retry_use_local_part defaults FALSE if unset */
359 if (tblock->retry_use_local_part == TRUE_UNSET)
360 tblock->retry_use_local_part = FALSE;
362 /* Set the default port according to the protocol */
365 ob->port = strcmpic(ob->protocol, US"lmtp") == 0
367 : strcmpic(ob->protocol, US"smtps") == 0
368 ? US"smtps" : US"smtp";
370 /* Set up the setup entry point, to be called before subprocesses for this
373 tblock->setup = smtp_transport_setup;
375 /* Complain if any of the timeouts are zero. */
377 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
378 ob->final_timeout <= 0)
379 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
380 "command, data, or final timeout value is zero for %s transport",
383 /* If hosts_override is set and there are local hosts, set the global
384 flag that stops verify from showing router hosts. */
386 if (ob->hosts_override && ob->hosts) tblock->overrides_hosts = TRUE;
388 /* If there are any fallback hosts listed, build a chain of host items
389 for them, but do not do any lookups at this time. */
391 store_pool = POOL_PERM;
392 host_build_hostlist(&ob->fallback_hostlist, ob->fallback_hosts, FALSE);
393 store_pool = old_pool;
400 /*************************************************
401 * Set delivery info into all active addresses *
402 *************************************************/
404 /* Only addresses whose status is >= PENDING are relevant. A lesser
405 status means that an address is not currently being processed.
408 addrlist points to a chain of addresses
409 errno_value to put in each address's errno field
410 msg to put in each address's message field
411 rc to put in each address's transport_return field
412 pass_message if TRUE, set the "pass message" flag in the address
413 host if set, mark addrs as having used this host
414 smtp_greeting from peer
415 helo_response from peer
416 start points to timestamp of delivery start
418 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
419 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
420 this particular type of timeout.
426 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
427 BOOL pass_message, host_item * host,
428 #ifdef EXPERIMENTAL_DSN_INFO
429 const uschar * smtp_greeting, const uschar * helo_response,
431 struct timeval * start
435 struct timeval deliver_time;
437 if (errno_value == ERRNO_CONNECTTIMEOUT)
439 errno_value = ETIMEDOUT;
440 orvalue = RTEF_CTOUT;
442 timesince(&deliver_time, start);
444 for (address_item * addr = addrlist; addr; addr = addr->next)
445 if (addr->transport_return >= PENDING)
447 addr->basic_errno = errno_value;
448 addr->more_errno |= orvalue;
449 addr->delivery_time = deliver_time;
453 if (pass_message) setflag(addr, af_pass_message);
455 addr->transport_return = rc;
458 addr->host_used = host;
459 #ifdef EXPERIMENTAL_DSN_INFO
461 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
462 addr->smtp_greeting = smtp_greeting;
465 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
466 addr->helo_response = helo_response;
473 set_errno_nohost(address_item * addrlist, int errno_value, uschar * msg, int rc,
474 BOOL pass_message, struct timeval * start)
476 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL,
477 #ifdef EXPERIMENTAL_DSN_INFO
484 /*************************************************
485 * Check an SMTP response *
486 *************************************************/
488 /* This function is given an errno code and the SMTP response buffer
489 to analyse, together with the host identification for generating messages. It
490 sets an appropriate message and puts the first digit of the response code into
491 the yield variable. If no response was actually read, a suitable digit is
495 host the current host, to get its name for messages
496 errno_value pointer to the errno value
497 more_errno from the top address for use with ERRNO_FILTER_FAIL
498 buffer the SMTP response buffer
499 yield where to put a one-digit SMTP response code
500 message where to put an error message
501 pass_message set TRUE if message is an SMTP response
503 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
507 check_response(host_item *host, int *errno_value, int more_errno,
508 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
510 uschar * pl = pipelining_active ? US"pipelined " : US"";
513 *yield = '4'; /* Default setting is to give a temporary error */
517 case ETIMEDOUT: /* Handle response timeout */
518 *message = US string_sprintf("SMTP timeout after %s%s",
520 if (transport_count > 0)
521 *message = US string_sprintf("%s (%d bytes written)", *message,
525 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
526 s = string_printing(buffer);
527 while (isspace(*s)) s++;
529 ? string_sprintf("Malformed SMTP reply (an empty line) "
530 "in response to %s%s", pl, smtp_command)
531 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
532 pl, smtp_command, s);
535 case ERRNO_TLSFAILURE: /* Handle bad first read; can happen with
537 *message = US"bad first read from TLS conn";
540 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
541 can't send QUIT as we mustn't end the DATA. */
542 *message = string_sprintf("transport filter process failed (%d)%s",
544 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
547 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
548 can't send QUIT as we mustn't end the DATA. */
550 string_sprintf("failed to expand headers_add or headers_remove: %s",
551 expand_string_message);
554 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
555 *message = US"failed to write a data block";
559 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
560 *message = US"utf8 support required but not offered for forwarding";
561 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
566 /* Handle error responses from the remote mailer. */
570 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
571 "%s", pl, smtp_command, s = string_printing(buffer));
572 *pass_message = TRUE;
577 /* No data was read. If there is no errno, this must be the EOF (i.e.
578 connection closed) case, which causes deferral. An explicit connection reset
579 error has the same effect. Otherwise, put the host's identity in the message,
580 leaving the errno value to be interpreted as well. In all cases, we have to
581 assume the connection is now dead. */
583 if (*errno_value == 0 || *errno_value == ECONNRESET)
585 *errno_value = ERRNO_SMTPCLOSED;
586 *message = US string_sprintf("Remote host closed connection "
587 "in response to %s%s", pl, smtp_command);
590 *message = US string_sprintf("%s [%s]", host->name, host->address);
597 /*************************************************
598 * Write error message to logs *
599 *************************************************/
601 /* This writes to the main log and to the message log.
604 host the current host
605 detail the current message (addr_item->message)
606 basic_errno the errno (addr_item->basic_errno)
612 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
614 gstring * message = LOGGING(outgoing_port)
615 ? string_fmt_append(NULL, "H=%s [%s]:%d", host->name, host->address,
616 host->port == PORT_NONE ? 25 : host->port)
617 : string_fmt_append(NULL, "H=%s [%s]", host->name, host->address);
621 message = string_fmt_append(message, ": %s", suffix);
623 message = string_fmt_append(message, ": %s", strerror(basic_errno));
626 message = string_fmt_append(message, " %s", exim_errstr(basic_errno));
628 log_write(0, LOG_MAIN, "%s", string_from_gstring(message));
629 deliver_msglog("%s %s\n", tod_stamp(tod_log), message->s);
633 msglog_line(host_item * host, uschar * message)
635 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
636 host->name, host->address, message);
641 #ifndef DISABLE_EVENT
642 /*************************************************
643 * Post-defer action *
644 *************************************************/
646 /* This expands an arbitrary per-transport string.
647 It might, for example, be used to write to the database log.
650 addr the address item containing error information
651 host the current host
658 deferred_event_raise(address_item * addr, host_item * host, uschar * evstr)
660 uschar * action = addr->transport->event_action;
661 const uschar * save_domain;
667 save_domain = deliver_domain;
668 save_local = deliver_localpart;
670 /*XXX would ip & port already be set up? */
671 deliver_host_address = string_copy(host->address);
672 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
673 event_defer_errno = addr->basic_errno;
675 router_name = addr->router->name;
676 transport_name = addr->transport->name;
677 deliver_domain = addr->domain;
678 deliver_localpart = addr->local_part;
680 (void) event_raise(action, evstr,
682 ? addr->basic_errno > 0
683 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
684 : string_copy(addr->message)
685 : addr->basic_errno > 0
686 ? string_copy(US strerror(addr->basic_errno))
690 deliver_localpart = save_local;
691 deliver_domain = save_domain;
692 router_name = transport_name = NULL;
696 /*************************************************
697 * Reap SMTP specific responses *
698 *************************************************/
700 smtp_discard_responses(smtp_context * sx, smtp_transport_options_block * ob,
703 uschar flushbuffer[4096];
707 if (!smtp_read_response(sx, flushbuffer, sizeof(flushbuffer),
708 '2', ob->command_timeout)
709 && (errno != 0 || flushbuffer[0] == 0))
716 /* Return boolean success */
719 smtp_reap_banner(smtp_context * sx)
722 #if defined(__linux__) && defined(TCP_QUICKACK)
723 { /* Hack to get QUICKACK disabled; has to be right after 3whs, and has to on->off */
724 int sock = sx->cctx.sock;
725 struct pollfd p = {.fd = sock, .events = POLLOUT};
726 if (poll(&p, 1, 1000) >= 0) /* retval test solely for compiler quitening */
728 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &on, sizeof(on));
729 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
733 good_response = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
734 '2', (SOB sx->conn_args.ob)->command_timeout);
735 #ifdef EXPERIMENTAL_DSN_INFO
736 sx->smtp_greeting = string_copy(sx->buffer);
738 return good_response;
742 smtp_reap_ehlo(smtp_context * sx)
744 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
745 (SOB sx->conn_args.ob)->command_timeout))
747 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
749 #ifdef EXPERIMENTAL_DSN_INFO
750 sx->helo_response = string_copy(sx->buffer);
756 #ifdef EXPERIMENTAL_DSN_INFO
757 sx->helo_response = string_copy(sx->buffer);
759 #ifndef DISABLE_EVENT
760 (void) event_raise(sx->conn_args.tblock->event_action,
761 US"smtp:ehlo", sx->buffer, NULL);
767 /* Grab a string differentiating server behind a loadbalancer, for TLS
768 resumption when such servers do not share a session-cache */
771 ehlo_response_lbserver(smtp_context * sx, smtp_transport_options_block * ob)
773 #if !defined(DISABLE_TLS) && !defined(DISABLE_TLS_RESUME)
775 uschar * save_item = iterate_item;
777 if (sx->conn_args.have_lbserver)
779 iterate_item = sx->buffer;
780 s = expand_cstring(ob->host_name_extract);
781 iterate_item = save_item;
782 sx->conn_args.host_lbserver = s && !*s ? NULL : s;
783 sx->conn_args.have_lbserver = TRUE;
789 /******************************************************************************/
791 #ifdef EXPERIMENTAL_ESMTP_LIMITS
792 /* If TLS, or TLS not offered, called with the EHLO response in the buffer.
793 Check it for a LIMITS keyword and parse values into the smtp context structure.
795 We don't bother with peers that we won't talk TLS to, even though they can,
796 just ignore their LIMITS advice (if any) and treat them as if they do not.
797 This saves us dealing with a duplicate set of values. */
800 ehlo_response_limits_read(smtp_context * sx)
804 /* matches up to just after the first space after the keyword */
806 if (regex_match(regex_LIMITS, sx->buffer, -1, &match))
807 for (const uschar * s = sx->buffer + Ustrlen(match); *s; )
809 while (isspace(*s)) s++;
810 if (*s == '\n') break;
812 if (strncmpic(s, US"MAILMAX=", 8) == 0)
814 sx->peer_limit_mail = atoi(CS (s += 8));
815 while (isdigit(*s)) s++;
817 else if (strncmpic(s, US"RCPTMAX=", 8) == 0)
819 sx->peer_limit_rcpt = atoi(CS (s += 8));
820 while (isdigit(*s)) s++;
822 else if (strncmpic(s, US"RCPTDOMAINMAX=", 14) == 0)
824 sx->peer_limit_rcptdom = atoi(CS (s += 14));
825 while (isdigit(*s)) s++;
828 while (*s && !isspace(*s)) s++;
832 /* Apply given values to the current connection */
834 ehlo_limits_apply(smtp_context * sx,
835 unsigned limit_mail, unsigned limit_rcpt, unsigned limit_rcptdom)
837 if (limit_mail && limit_mail < sx->max_mail) sx->max_mail = limit_mail;
838 if (limit_rcpt && limit_rcpt < sx->max_rcpt) sx->max_rcpt = limit_rcpt;
841 DEBUG(D_transport) debug_printf("will treat as !multi_domain\n");
842 sx->single_rcpt_domain = TRUE;
846 /* Apply values from EHLO-resp to the current connection */
848 ehlo_response_limits_apply(smtp_context * sx)
850 ehlo_limits_apply(sx, sx->peer_limit_mail, sx->peer_limit_rcpt,
851 sx->peer_limit_rcptdom);
854 /* Apply values read from cache to the current connection */
856 ehlo_cache_limits_apply(smtp_context * sx)
858 # ifndef DISABLE_PIPE_CONNECT
859 ehlo_limits_apply(sx, sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
860 sx->ehlo_resp.limit_rcptdom);
863 #endif /*EXPERIMENTAL_ESMTP_LIMITS*/
865 /******************************************************************************/
867 #ifndef DISABLE_PIPE_CONNECT
869 ehlo_cache_key(const smtp_context * sx)
871 host_item * host = sx->conn_args.host;
872 return Ustrchr(host->address, ':')
873 ? string_sprintf("[%s]:%d.EHLO", host->address,
874 host->port == PORT_NONE ? sx->port : host->port)
875 : string_sprintf("%s:%d.EHLO", host->address,
876 host->port == PORT_NONE ? sx->port : host->port);
879 /* Cache EHLO-response info for use by early-pipe.
881 - During a normal flow on EHLO response (either cleartext or under TLS),
882 when we are willing to do PIPECONNECT and it is offered
883 - During an early-pipe flow on receiving the actual EHLO response and noting
884 disparity versus the cached info used, when PIPECONNECT is still being offered
886 We assume that suitable values have been set in the sx.ehlo_resp structure for
887 features and auths; we handle the copy of limits. */
890 write_ehlo_cache_entry(smtp_context * sx)
892 open_db dbblock, * dbm_file;
894 # ifdef EXPERIMENTAL_ESMTP_LIMITS
895 sx->ehlo_resp.limit_mail = sx->peer_limit_mail;
896 sx->ehlo_resp.limit_rcpt = sx->peer_limit_rcpt;
897 sx->ehlo_resp.limit_rcptdom = sx->peer_limit_rcptdom;
900 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
902 uschar * ehlo_resp_key = ehlo_cache_key(sx);
903 dbdata_ehlo_resp er = { .data = sx->ehlo_resp };
906 # ifdef EXPERIMENTAL_ESMTP_LIMITS
907 if (sx->ehlo_resp.limit_mail || sx->ehlo_resp.limit_rcpt || sx->ehlo_resp.limit_rcptdom)
908 debug_printf("writing clr %04x/%04x cry %04x/%04x lim %05d/%05d/%05d\n",
909 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
910 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths,
911 sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
912 sx->ehlo_resp.limit_rcptdom);
915 debug_printf("writing clr %04x/%04x cry %04x/%04x\n",
916 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
917 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths);
919 dbfn_write(dbm_file, ehlo_resp_key, &er, (int)sizeof(er));
920 dbfn_close(dbm_file);
925 invalidate_ehlo_cache_entry(smtp_context * sx)
927 open_db dbblock, * dbm_file;
929 if ( sx->early_pipe_active
930 && (dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
932 uschar * ehlo_resp_key = ehlo_cache_key(sx);
933 dbfn_delete(dbm_file, ehlo_resp_key);
934 dbfn_close(dbm_file);
939 read_ehlo_cache_entry(smtp_context * sx)
944 if (!(dbm_file = dbfn_open(US"misc", O_RDONLY, &dbblock, FALSE, TRUE)))
945 { DEBUG(D_transport) debug_printf("ehlo-cache: no misc DB\n"); }
948 uschar * ehlo_resp_key = ehlo_cache_key(sx);
949 dbdata_ehlo_resp * er;
951 if (!(er = dbfn_read_enforce_length(dbm_file, ehlo_resp_key, sizeof(dbdata_ehlo_resp))))
952 { DEBUG(D_transport) debug_printf("no ehlo-resp record\n"); }
953 else if (time(NULL) - er->time_stamp > retry_data_expire)
955 DEBUG(D_transport) debug_printf("ehlo-resp record too old\n");
956 dbfn_close(dbm_file);
957 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
958 dbfn_delete(dbm_file, ehlo_resp_key);
963 # ifdef EXPERIMENTAL_ESMTP_LIMITS
964 if (er->data.limit_mail || er->data.limit_rcpt || er->data.limit_rcptdom)
965 debug_printf("EHLO response bits from cache:"
966 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x lim %05d/%05d/%05d\n",
967 er->data.cleartext_features, er->data.cleartext_auths,
968 er->data.crypted_features, er->data.crypted_auths,
969 er->data.limit_mail, er->data.limit_rcpt, er->data.limit_rcptdom);
972 debug_printf("EHLO response bits from cache:"
973 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x\n",
974 er->data.cleartext_features, er->data.cleartext_auths,
975 er->data.crypted_features, er->data.crypted_auths);
977 sx->ehlo_resp = er->data;
978 # ifdef EXPERIMENTAL_ESMTP_LIMITS
979 ehlo_cache_limits_apply(sx);
981 dbfn_close(dbm_file);
984 dbfn_close(dbm_file);
991 /* Return an auths bitmap for the set of AUTH methods offered by the server
992 which match our authenticators. */
994 static unsigned short
995 study_ehlo_auths(smtp_context * sx)
1000 unsigned short authbits = 0;
1002 if (!sx->esmtp) return 0;
1003 if (!regex_AUTH) regex_AUTH = regex_must_compile(AUTHS_REGEX, MCS_NOFLAGS, TRUE);
1004 if (!regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)) return 0;
1005 expand_nmax = -1; /* reset */
1006 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1008 for (au = auths, authnum = 0; au; au = au->next, authnum++) if (au->client)
1010 const uschar * list = names;
1012 for (int sep = ' '; s = string_nextinlist(&list, &sep, NULL, 0); )
1013 if (strcmpic(au->public_name, s) == 0)
1014 { authbits |= BIT(authnum); break; }
1018 debug_printf("server offers %s AUTH, methods '%s', bitmap 0x%04x\n",
1019 tls_out.active.sock >= 0 ? "crypted" : "plaintext", names, authbits);
1021 if (tls_out.active.sock >= 0)
1022 sx->ehlo_resp.crypted_auths = authbits;
1024 sx->ehlo_resp.cleartext_auths = authbits;
1031 /* Wait for and check responses for early-pipelining.
1033 Called from the lower-level smtp_read_response() function
1034 used for general code that assume synchronisation, if context
1035 flags indicate outstanding early-pipelining commands. Also
1036 called fom sync_responses() which handles pipelined commands.
1039 sx smtp connection context
1040 countp number of outstanding responses, adjusted on return
1044 DEFER error on first read of TLS'd conn
1045 FAIL SMTP error in response
1048 smtp_reap_early_pipe(smtp_context * sx, int * countp)
1050 BOOL pending_BANNER = sx->pending_BANNER;
1051 BOOL pending_EHLO = sx->pending_EHLO;
1054 sx->pending_BANNER = FALSE; /* clear early to avoid recursion */
1055 sx->pending_EHLO = FALSE;
1059 DEBUG(D_transport) debug_printf("%s expect banner\n", __FUNCTION__);
1061 if (!smtp_reap_banner(sx))
1063 DEBUG(D_transport) debug_printf("bad banner\n");
1064 if (tls_out.active.sock >= 0) rc = DEFER;
1067 /*XXX EXPERIMENTAL_ESMTP_LIMITS ? */
1068 ehlo_response_lbserver(sx, sx->conn_args.ob);
1073 unsigned peer_offered;
1074 unsigned short authbits = 0, * ap;
1076 DEBUG(D_transport) debug_printf("%s expect ehlo\n", __FUNCTION__);
1078 if (!smtp_reap_ehlo(sx))
1080 DEBUG(D_transport) debug_printf("bad response for EHLO\n");
1081 if (tls_out.active.sock >= 0) rc = DEFER;
1085 /* Compare the actual EHLO response extensions and AUTH methods to the cached
1086 value we assumed; on difference, dump or rewrite the cache and arrange for a
1089 ap = tls_out.active.sock < 0
1090 ? &sx->ehlo_resp.cleartext_auths : &sx->ehlo_resp.crypted_auths;
1092 peer_offered = ehlo_response(sx->buffer,
1093 (tls_out.active.sock < 0 ? OPTION_TLS : 0)
1094 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
1095 | OPTION_UTF8 | OPTION_EARLY_PIPE
1097 # ifdef EXPERIMENTAL_ESMTP_LIMITS
1098 if (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1099 ehlo_response_limits_read(sx);
1101 if ( peer_offered != sx->peer_offered
1102 || (authbits = study_ehlo_auths(sx)) != *ap)
1105 debug_printf("EHLO %s extensions changed, 0x%04x/0x%04x -> 0x%04x/0x%04x\n",
1106 tls_out.active.sock < 0 ? "cleartext" : "crypted",
1107 sx->peer_offered, *ap, peer_offered, authbits);
1108 if (peer_offered & OPTION_EARLY_PIPE)
1110 *(tls_out.active.sock < 0
1111 ? &sx->ehlo_resp.cleartext_features : &sx->ehlo_resp.crypted_features) =
1114 write_ehlo_cache_entry(sx);
1117 invalidate_ehlo_cache_entry(sx);
1119 return OK; /* just carry on */
1121 # ifdef EXPERIMENTAL_ESMTP_LIMITS
1122 /* If we are handling LIMITS, compare the actual EHLO LIMITS values with the
1123 cached values and invalidate cache if different. OK to carry on with
1124 connect since values are advisory. */
1126 if ( (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1127 && ( sx->peer_limit_mail != sx->ehlo_resp.limit_mail
1128 || sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt
1129 || sx->peer_limit_rcptdom != sx->ehlo_resp.limit_rcptdom
1134 debug_printf("EHLO LIMITS changed:");
1135 if (sx->peer_limit_mail != sx->ehlo_resp.limit_mail)
1136 debug_printf(" MAILMAX %u -> %u\n", sx->ehlo_resp.limit_mail, sx->peer_limit_mail);
1137 else if (sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt)
1138 debug_printf(" RCPTMAX %u -> %u\n", sx->ehlo_resp.limit_rcpt, sx->peer_limit_rcpt);
1140 debug_printf(" RCPTDOMAINMAX %u -> %u\n", sx->ehlo_resp.limit_rcptdom, sx->peer_limit_rcptdom);
1142 invalidate_ehlo_cache_entry(sx);
1150 invalidate_ehlo_cache_entry(sx);
1151 (void) smtp_discard_responses(sx, sx->conn_args.ob, *countp);
1154 #endif /*!DISABLE_PIPE_CONNECT*/
1157 /*************************************************
1158 * Synchronize SMTP responses *
1159 *************************************************/
1161 /* This function is called from smtp_deliver() to receive SMTP responses from
1162 the server, and match them up with the commands to which they relate. When
1163 PIPELINING is not in use, this function is called after every command, and is
1164 therefore somewhat over-engineered, but it is simpler to use a single scheme
1165 that works both with and without PIPELINING instead of having two separate sets
1168 The set of commands that are buffered up with pipelining may start with MAIL
1169 and may end with DATA; in between are RCPT commands that correspond to the
1170 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
1171 etc.) are never buffered.
1173 Errors after MAIL or DATA abort the whole process leaving the response in the
1174 buffer. After MAIL, pending responses are flushed, and the original command is
1175 re-instated in big_buffer for error messages. For RCPT commands, the remote is
1176 permitted to reject some recipient addresses while accepting others. However
1177 certain errors clearly abort the whole process. Set the value in
1178 transport_return to PENDING_OK if the address is accepted. If there is a
1179 subsequent general error, it will get reset accordingly. If not, it will get
1180 converted to OK at the end.
1183 sx smtp connection context
1184 count the number of responses to read
1185 pending_DATA 0 if last command sent was not DATA
1186 +1 if previously had a good recipient
1187 -1 if not previously had a good recipient
1189 Returns: 3 if at least one address had 2xx and one had 5xx
1190 2 if at least one address had 5xx but none had 2xx
1191 1 if at least one host had a 2xx response, but none had 5xx
1192 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
1193 -1 timeout while reading RCPT response
1194 -2 I/O or other non-response error for RCPT
1195 -3 DATA or MAIL failed - errno and buffer set
1196 -4 banner or EHLO failed (early-pipelining)
1197 -5 banner or EHLO failed (early-pipelining, TLS)
1201 sync_responses(smtp_context * sx, int count, int pending_DATA)
1203 address_item * addr = sx->sync_addr;
1204 smtp_transport_options_block * ob = sx->conn_args.ob;
1207 #ifndef DISABLE_PIPE_CONNECT
1209 if ((rc = smtp_reap_early_pipe(sx, &count)) != OK)
1210 return rc == FAIL ? -4 : -5;
1213 /* Handle the response for a MAIL command. On error, reinstate the original
1214 command in big_buffer for error message use, and flush any further pending
1215 responses before returning, except after I/O errors and timeouts. */
1217 if (sx->pending_MAIL)
1219 DEBUG(D_transport) debug_printf("%s expect mail\n", __FUNCTION__);
1221 sx->pending_MAIL = sx->RCPT_452 = FALSE;
1222 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1223 '2', ob->command_timeout))
1225 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
1226 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
1227 if (errno == ERRNO_TLSFAILURE)
1229 if (errno == 0 && sx->buffer[0] != 0)
1232 if (sx->buffer[0] == '4')
1234 save_errno = ERRNO_MAIL4XX;
1235 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1237 count = smtp_discard_responses(sx, ob, count);
1241 if (pending_DATA) count--; /* Number of RCPT responses to come */
1242 while (count-- > 0) /* Mark any pending addrs with the host used */
1244 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
1245 addr->host_used = sx->conn_args.host;
1252 if (pending_DATA) count--; /* Number of RCPT responses to come */
1254 /* Read and handle the required number of RCPT responses, matching each one up
1255 with an address by scanning for the next address whose status is PENDING_DEFER.
1260 while (addr->transport_return != PENDING_DEFER)
1261 if (!(addr = addr->next))
1264 /* The address was accepted */
1265 addr->host_used = sx->conn_args.host;
1267 DEBUG(D_transport) debug_printf("%s expect rcpt for %s\n", __FUNCTION__, addr->address);
1268 if (smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1269 '2', ob->command_timeout))
1272 addr->transport_return = PENDING_OK;
1274 /* If af_dr_retry_exists is set, there was a routing delay on this address;
1275 ensure that any address-specific retry record is expunged. We do this both
1276 for the basic key and for the version that also includes the sender. */
1278 if (testflag(addr, af_dr_retry_exists))
1280 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
1282 retry_add_item(addr, altkey, rf_delete);
1283 retry_add_item(addr, addr->address_retry_key, rf_delete);
1287 /* Error on first TLS read */
1289 else if (errno == ERRNO_TLSFAILURE)
1292 /* Timeout while reading the response */
1294 else if (errno == ETIMEDOUT)
1296 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
1297 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1298 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE, &sx->delivery_start);
1299 retry_add_item(addr, addr->address_retry_key, 0);
1300 update_waiting = FALSE;
1304 /* Handle other errors in obtaining an SMTP response by returning -1. This
1305 will cause all the addresses to be deferred. Restore the SMTP command in
1306 big_buffer for which we are checking the response, so the error message
1309 else if (errno != 0 || sx->buffer[0] == 0)
1311 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer }, * g = &gs;
1313 /* Use taint-unchecked routines for writing into big_buffer, trusting
1314 that we'll never expand it. */
1316 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, "RCPT TO:<%s>",
1317 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1318 string_from_gstring(g);
1322 /* Handle SMTP permanent and temporary response codes. */
1327 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
1328 "%s", transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes),
1329 string_printing(sx->buffer));
1330 setflag(addr, af_pass_message);
1332 msglog_line(sx->conn_args.host, addr->message);
1334 /* The response was 5xx */
1336 if (sx->buffer[0] == '5')
1338 addr->transport_return = FAIL;
1342 /* The response was 4xx */
1346 addr->transport_return = DEFER;
1347 addr->basic_errno = ERRNO_RCPT4XX;
1348 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1352 #ifndef DISABLE_EVENT
1353 event_defer_errno = addr->more_errno;
1354 msg_event_raise(US"msg:rcpt:host:defer", addr);
1356 /* If a 452 and we've had at least one 2xx or 5xx, set next_addr to the
1357 start point for another MAIL command. */
1359 if (addr->more_errno >> 8 == 52 && yield & 3)
1361 if (!sx->RCPT_452) /* initialised at MAIL-ack above */
1364 debug_printf("%s: seen first 452 too-many-rcpts\n", __FUNCTION__);
1365 sx->RCPT_452 = TRUE;
1366 sx->next_addr = addr;
1368 addr->transport_return = PENDING_DEFER;
1369 addr->basic_errno = 0;
1373 /* Log temporary errors if there are more hosts to be tried.
1374 If not, log this last one in the == line. */
1376 if (sx->conn_args.host->next)
1377 if (LOGGING(outgoing_port))
1378 log_write(0, LOG_MAIN, "H=%s [%s]:%d %s", sx->conn_args.host->name,
1379 sx->conn_args.host->address,
1380 sx->port == PORT_NONE ? 25 : sx->port, addr->message);
1382 log_write(0, LOG_MAIN, "H=%s [%s]: %s", sx->conn_args.host->name,
1383 sx->conn_args.host->address, addr->message);
1385 #ifndef DISABLE_EVENT
1387 msg_event_raise(US"msg:rcpt:defer", addr);
1390 /* Do not put this message on the list of those waiting for specific
1391 hosts, as otherwise it is likely to be tried too often. */
1393 update_waiting = FALSE;
1395 /* Add a retry item for the address so that it doesn't get tried again
1396 too soon. If address_retry_include_sender is true, add the sender address
1397 to the retry key. */
1399 retry_add_item(addr,
1400 ob->address_retry_include_sender
1401 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
1402 : addr->address_retry_key,
1408 if (count && !(addr = addr->next))
1410 } /* Loop for next RCPT response */
1412 /* Update where to start at for the next block of responses, unless we
1413 have already handled all the addresses. */
1415 if (addr) sx->sync_addr = addr->next;
1417 /* Handle a response to DATA. If we have not had any good recipients, either
1418 previously or in this block, the response is ignored. */
1420 if (pending_DATA != 0)
1422 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1423 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1424 '3', ob->command_timeout))
1430 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1433 if (pending_DATA > 0 || (yield & 1) != 0)
1435 if (errno == 0 && sx->buffer[0] == '4')
1437 errno = ERRNO_DATA4XX;
1438 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1442 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1443 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1444 "is in use and there were no good recipients\n", msg);
1448 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1449 present) received 3xx. If any RCPTs were handled and yielded anything other
1450 than 4xx, yield will be set non-zero. */
1459 /* Try an authenticator's client entry */
1462 try_authenticator(smtp_context * sx, auth_instance * au)
1464 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1465 host_item * host = sx->conn_args.host; /* host to deliver to */
1468 /* Set up globals for error messages */
1470 authenticator_name = au->name;
1471 driver_srcfile = au->srcfile;
1472 driver_srcline = au->srcline;
1474 sx->outblock.authenticating = TRUE;
1475 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1476 sx->buffer, sizeof(sx->buffer));
1477 sx->outblock.authenticating = FALSE;
1478 driver_srcfile = authenticator_name = NULL; driver_srcline = 0;
1479 DEBUG(D_transport) debug_printf("%s authenticator yielded %s\n", au->name, rc_names[rc]);
1481 /* A temporary authentication failure must hold up delivery to
1482 this host. After a permanent authentication failure, we carry on
1483 to try other authentication methods. If all fail hard, try to
1484 deliver the message unauthenticated unless require_auth was set. */
1489 f.smtp_authenticated = TRUE; /* stops the outer loop */
1490 client_authenticator = au->name;
1491 if (au->set_client_id)
1492 client_authenticated_id = expand_string(au->set_client_id);
1495 /* Failure after writing a command */
1500 /* Failure after reading a response */
1504 uschar * logmsg = NULL;
1506 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1507 #ifndef DISABLE_EVENT
1509 uschar * save_name = sender_host_authenticated;
1510 sender_host_authenticated = au->name;
1511 if ((logmsg = event_raise(sx->conn_args.tblock->event_action, US"auth:fail",
1513 log_write(0, LOG_MAIN, "%s", logmsg);
1514 sender_host_authenticated = save_name;
1518 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1519 au->name, host->name, host->address, sx->buffer);
1523 /* Failure by some other means. In effect, the authenticator
1524 decided it wasn't prepared to handle this case. Typically this
1525 is the result of "fail" in an expansion string. Do we need to
1526 log anything here? Feb 2006: a message is now put in the buffer
1527 if logging is required. */
1530 if (*sx->buffer != 0)
1531 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1532 "authentication H=%s [%s] %s", au->name, host->name,
1533 host->address, sx->buffer);
1536 /* Internal problem, message in buffer. */
1539 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1540 DEFER, FALSE, &sx->delivery_start);
1549 /* Do the client side of smtp-level authentication.
1552 sx smtp connection context
1554 sx->buffer should have the EHLO response from server (gets overwritten)
1557 OK Success, or failed (but not required): global "smtp_authenticated" set
1558 DEFER Failed authentication (and was required)
1559 ERROR Internal problem
1561 FAIL_SEND Failed communications - transmit
1566 smtp_auth(smtp_context * sx)
1568 host_item * host = sx->conn_args.host; /* host to deliver to */
1569 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1570 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1571 #ifndef DISABLE_PIPE_CONNECT
1572 unsigned short authbits = tls_out.active.sock >= 0
1573 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1575 uschar * fail_reason = US"server did not advertise AUTH support";
1577 f.smtp_authenticated = FALSE;
1578 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1581 regex_AUTH = regex_must_compile(AUTHS_REGEX, MCS_NOFLAGS, TRUE);
1583 /* Is the server offering AUTH? */
1587 #ifndef DISABLE_PIPE_CONNECT
1588 sx->early_pipe_active ? authbits
1591 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1594 uschar * names = NULL;
1595 expand_nmax = -1; /* reset */
1597 #ifndef DISABLE_PIPE_CONNECT
1598 if (!sx->early_pipe_active)
1600 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1602 /* Must not do this check until after we have saved the result of the
1603 regex match above as the check could be another RE. */
1605 if ( require_auth == OK
1606 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1608 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1609 fail_reason = US"no common mechanisms were found";
1611 #ifndef DISABLE_PIPE_CONNECT
1612 if (sx->early_pipe_active)
1614 /* Scan our authenticators (which support use by a client and were offered
1615 by the server (checked at cache-write time)), not suppressed by
1616 client_condition. If one is found, attempt to authenticate by calling its
1617 client function. We are limited to supporting up to 16 authenticator
1618 public-names by the number of bits in a short. */
1624 for (bitnum = 0, au = auths;
1625 !f.smtp_authenticated && au && bitnum < 16;
1626 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1628 if ( au->client_condition
1629 && !expand_check_condition(au->client_condition, au->name,
1630 US"client authenticator"))
1632 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1633 au->name, "client_condition is false");
1637 /* Found data for a listed mechanism. Call its client entry. Set
1638 a flag in the outblock so that data is overwritten after sending so
1639 that reflections don't show it. */
1641 fail_reason = US"authentication attempt(s) failed";
1643 if ((rc = try_authenticator(sx, au)) != OK)
1650 /* Scan the configured authenticators looking for one which is configured
1651 for use as a client, which is not suppressed by client_condition, and
1652 whose name matches an authentication mechanism supported by the server.
1653 If one is found, attempt to authenticate by calling its client function.
1656 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1661 || ( au->client_condition
1662 && !expand_check_condition(au->client_condition, au->name,
1663 US"client authenticator")))
1665 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1667 (au->client)? "client_condition is false" :
1668 "not configured as a client");
1672 /* Loop to scan supported server mechanisms */
1676 int len = Ustrlen(au->public_name);
1679 while (isspace(*p)) p++;
1681 if (strncmpic(au->public_name, p, len) != 0 ||
1682 (p[len] != 0 && !isspace(p[len])))
1684 while (*p != 0 && !isspace(*p)) p++;
1688 /* Found data for a listed mechanism. Call its client entry. Set
1689 a flag in the outblock so that data is overwritten after sending so
1690 that reflections don't show it. */
1692 fail_reason = US"authentication attempt(s) failed";
1694 if ((rc = try_authenticator(sx, au)) != OK)
1697 break; /* If not authenticated, try next authenticator */
1698 } /* Loop for scanning supported server mechanisms */
1699 } /* Loop for further authenticators */
1703 /* If we haven't authenticated, but are required to, give up. */
1705 if (require_auth == OK && !f.smtp_authenticated)
1707 #ifndef DISABLE_PIPE_CONNECT
1708 invalidate_ehlo_cache_entry(sx);
1710 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1711 string_sprintf("authentication required but %s", fail_reason), DEFER,
1712 FALSE, &sx->delivery_start);
1720 /* Construct AUTH appendix string for MAIL TO */
1723 sx context for smtp connection
1724 p point in sx->buffer to build string
1725 addrlist chain of potential addresses to deliver
1727 Globals f.smtp_authenticated
1728 client_authenticated_sender
1729 Return True on error, otherwise buffer has (possibly empty) terminated string
1733 smtp_mail_auth_str(smtp_context * sx, uschar * p, address_item * addrlist)
1735 smtp_transport_options_block * ob = sx->conn_args.ob;
1736 uschar * local_authenticated_sender = authenticated_sender;
1739 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n",
1740 authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1743 if (ob->authenticated_sender)
1745 uschar * new = expand_string(ob->authenticated_sender);
1748 if (!f.expand_string_forcedfail)
1750 uschar *message = string_sprintf("failed to expand "
1751 "authenticated_sender: %s", expand_string_message);
1752 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
1757 local_authenticated_sender = new;
1760 /* Add the authenticated sender address if present */
1762 if ( (f.smtp_authenticated || ob->authenticated_sender_force)
1763 && local_authenticated_sender)
1765 string_format_nt(p, sizeof(sx->buffer) - (p-sx->buffer), " AUTH=%s",
1766 auth_xtextencode(local_authenticated_sender,
1767 Ustrlen(local_authenticated_sender)));
1768 client_authenticated_sender = string_copy(local_authenticated_sender);
1778 typedef struct smtp_compare_s
1780 uschar * current_sender_address;
1781 struct transport_instance * tblock;
1785 /* Create a unique string that identifies this message, it is based on
1786 sender_address, helo_data and tls_certificate if enabled.
1790 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1792 address_item * addr1;
1793 uschar * if1 = US"";
1794 uschar * helo1 = US"";
1796 uschar * tlsc1 = US"";
1798 uschar * save_sender_address = sender_address;
1799 uschar * local_identity = NULL;
1800 smtp_transport_options_block * ob = SOB tblock->options_block;
1802 sender_address = sender;
1804 addr1 = deliver_make_addr (sender, TRUE);
1805 deliver_set_expansions(addr1);
1808 if1 = expand_string(ob->interface);
1811 helo1 = expand_string(ob->helo_data);
1814 if (ob->tls_certificate)
1815 tlsc1 = expand_string(ob->tls_certificate);
1816 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1818 local_identity = string_sprintf ("%s^%s", if1, helo1);
1821 deliver_set_expansions(NULL);
1822 sender_address = save_sender_address;
1824 return local_identity;
1829 /* This routine is a callback that is called from transport_check_waiting.
1830 This function will evaluate the incoming message versus the previous
1831 message. If the incoming message is using a different local identity then
1832 we will veto this new message. */
1835 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1837 uschar * message_local_identity,
1838 * current_local_identity,
1839 * new_sender_address;
1841 current_local_identity =
1842 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1844 if (!(new_sender_address = spool_sender_from_msgid(message_id)))
1848 message_local_identity =
1849 smtp_local_identity(new_sender_address, s_compare->tblock);
1851 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1857 ehlo_response(uschar * buf, unsigned checks)
1859 PCRE2_SIZE bsize = Ustrlen(buf);
1860 pcre2_match_data * md = pcre2_match_data_create(1, pcre_gen_ctx);
1862 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1865 if ( checks & OPTION_TLS
1866 && pcre2_match(regex_STARTTLS,
1867 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1869 checks &= ~OPTION_TLS;
1871 if ( checks & OPTION_IGNQ
1872 && pcre2_match(regex_IGNOREQUOTA,
1873 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1874 checks &= ~OPTION_IGNQ;
1876 if ( checks & OPTION_CHUNKING
1877 && pcre2_match(regex_CHUNKING,
1878 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1879 checks &= ~OPTION_CHUNKING;
1881 #ifndef DISABLE_PRDR
1882 if ( checks & OPTION_PRDR
1883 && pcre2_match(regex_PRDR,
1884 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1886 checks &= ~OPTION_PRDR;
1889 if ( checks & OPTION_UTF8
1890 && pcre2_match(regex_UTF8,
1891 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1893 checks &= ~OPTION_UTF8;
1895 if ( checks & OPTION_DSN
1896 && pcre2_match(regex_DSN,
1897 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1898 checks &= ~OPTION_DSN;
1900 if ( checks & OPTION_PIPE
1901 && pcre2_match(regex_PIPELINING,
1902 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1903 checks &= ~OPTION_PIPE;
1905 if ( checks & OPTION_SIZE
1906 && pcre2_match(regex_SIZE,
1907 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1908 checks &= ~OPTION_SIZE;
1910 #ifndef DISABLE_PIPE_CONNECT
1911 if ( checks & OPTION_EARLY_PIPE
1912 && pcre2_match(regex_EARLY_PIPE,
1913 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1915 checks &= ~OPTION_EARLY_PIPE;
1917 /* pcre2_match_data_free(md); gen ctx needs no free */
1918 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1924 /* Callback for emitting a BDAT data chunk header.
1926 If given a nonzero size, first flush any buffered SMTP commands
1927 then emit the command.
1929 Reap previous SMTP command responses if requested, and always reap
1930 the response from a previous BDAT command.
1933 tctx transport context
1934 chunk_size value for SMTP BDAT command
1936 tc_chunk_last add LAST option to SMTP BDAT command
1937 tc_reap_prev reap response to previous SMTP commands
1941 DEFER TLS error on first read (EHLO-resp); errno set
1945 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1948 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1949 smtp_context * sx = tctx->smtp_context;
1953 /* Write SMTP chunk header command. If not reaping responses, note that
1954 there may be more writes (like, the chunk data) done soon. */
1958 #ifndef DISABLE_PIPE_CONNECT
1959 BOOL new_conn = !!(sx->outblock.conn_args);
1961 if((cmd_count = smtp_write_command(sx,
1962 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1963 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1964 ) < 0) return ERROR;
1965 if (flags & tc_chunk_last)
1966 data_command = string_copy(big_buffer); /* Save for later error message */
1967 #ifndef DISABLE_PIPE_CONNECT
1968 /* That command write could have been the one that made the connection.
1969 Copy the fd from the client conn ctx (smtp transport specific) to the
1970 generic transport ctx. */
1973 tctx->u.fd = sx->outblock.cctx->sock;
1977 prev_cmd_count = cmd_count += sx->cmd_count;
1979 /* Reap responses for any previous, but not one we just emitted */
1983 if (sx->pending_BDAT)
1986 if (flags & tc_reap_prev && prev_cmd_count > 0)
1988 DEBUG(D_transport) debug_printf("look for %d responses"
1989 " for previous pipelined cmds\n", prev_cmd_count);
1991 switch(sync_responses(sx, prev_cmd_count, 0))
1993 case 1: /* 2xx (only) => OK */
1994 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1995 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1996 case 0: break; /* No 2xx or 5xx, but no probs */
1998 case -5: errno = ERRNO_TLSFAILURE;
2000 #ifndef DISABLE_PIPE_CONNECT
2001 case -4: /* non-2xx for pipelined banner or EHLO */
2003 case -1: /* Timeout on RCPT */
2004 default: return ERROR; /* I/O error, or any MAIL/DATA error */
2007 if (!sx->pending_BDAT)
2008 pipelining_active = FALSE;
2011 /* Reap response for an outstanding BDAT */
2013 if (sx->pending_BDAT)
2015 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
2017 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
2018 ob->command_timeout))
2020 if (errno == 0 && sx->buffer[0] == '4')
2022 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
2023 sx->addrlist->more_errno |=
2024 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2029 sx->pending_BDAT = FALSE;
2030 pipelining_active = FALSE;
2032 else if (chunk_size > 0)
2033 sx->pending_BDAT = TRUE;
2036 sx->cmd_count = cmd_count;
2044 check_force_dane_conn(smtp_context * sx, smtp_transport_options_block * ob)
2047 if( sx->dane_required
2048 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2050 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2052 case OK: sx->conn_args.dane = TRUE;
2053 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2054 ob->tls_sni = sx->conn_args.host->name; /* force SNI */
2056 case FAIL_FORCED: break;
2057 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2058 string_sprintf("DANE error: tlsa lookup %s",
2060 rc, FALSE, &sx->delivery_start);
2061 # ifndef DISABLE_EVENT
2062 (void) event_raise(sx->conn_args.tblock->event_action,
2063 US"dane:fail", sx->dane_required
2064 ? US"dane-required" : US"dnssec-invalid",
2074 /*************************************************
2075 * Make connection for given message *
2076 *************************************************/
2080 sx connection context
2081 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2082 a second attempt after TLS initialization fails
2084 Returns: OK - the connection was made and the delivery attempted;
2085 fd is set in the conn context, tls_out set up.
2086 DEFER - the connection could not be made, or something failed
2087 while setting up the SMTP session, or there was a
2088 non-message-specific error, such as a timeout.
2089 ERROR - helo_data or add_headers or authenticated_sender is
2090 specified for this transport, and the string failed
2094 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
2096 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
2097 BOOL pass_message = FALSE;
2098 uschar * message = NULL;
2101 uschar * tls_errstr;
2104 /* Many lines of clearing individual elements of *sx that used to
2105 be here have been replaced by a full memset to zero (de41aff051).
2106 There are two callers, this file and verify.c . Now we only set
2107 up nonzero elements. */
2109 sx->conn_args.ob = ob;
2111 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
2112 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
2113 sx->send_rset = TRUE;
2114 sx->send_quit = TRUE;
2115 sx->setting_up = TRUE;
2117 sx->dsn_all_lasthop = TRUE;
2120 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
2123 if ((sx->max_mail = sx->conn_args.tblock->connection_max_messages) == 0) sx->max_mail = 999999;
2124 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
2125 sx->igquotstr = US"";
2126 if (!sx->helo_data) sx->helo_data = ob->helo_data;
2128 smtp_command = US"initial connection";
2130 /* Set up the buffer for reading SMTP response packets. */
2132 sx->inblock.buffer = sx->inbuffer;
2133 sx->inblock.buffersize = sizeof(sx->inbuffer);
2134 sx->inblock.ptr = sx->inbuffer;
2135 sx->inblock.ptrend = sx->inbuffer;
2137 /* Set up the buffer for holding SMTP commands while pipelining */
2139 sx->outblock.buffer = sx->outbuffer;
2140 sx->outblock.buffersize = sizeof(sx->outbuffer);
2141 sx->outblock.ptr = sx->outbuffer;
2143 /* Reset the parameters of a TLS session. */
2146 tls_out.cipher = NULL; /* the one we may use for this transport */
2147 tls_out.ourcert = NULL;
2148 tls_out.peercert = NULL;
2149 tls_out.peerdn = NULL;
2153 tls_out.ocsp = OCSP_NOT_REQ;
2154 #ifndef DISABLE_TLS_RESUME
2155 tls_out.resumption = 0;
2159 /* Flip the legacy TLS-related variables over to the outbound set in case
2160 they're used in the context of the transport. Don't bother resetting
2161 afterward (when being used by a transport) as we're in a subprocess.
2162 For verify, unflipped once the callout is dealt with */
2164 tls_modify_variables(&tls_out);
2169 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
2170 DEFER, FALSE, &sx->delivery_start);
2175 /* If we have a proxied TLS connection, check usability for this message */
2177 if (continue_hostname && continue_proxy_cipher)
2180 const uschar * sni = US"";
2182 # ifdef SUPPORT_DANE
2183 /* Check if the message will be DANE-verified; if so force TLS and its SNI */
2185 tls_out.dane_verified = FALSE;
2186 smtp_port_for_connect(sx->conn_args.host, sx->port);
2187 if ( sx->conn_args.host->dnssec == DS_YES
2188 && (rc = check_force_dane_conn(sx, ob)) != OK
2193 /* If the SNI or the DANE status required for the new message differs from the
2194 existing conn drop the connection to force a new one. */
2196 if (ob->tls_sni && !(sni = expand_cstring(ob->tls_sni)))
2197 log_write(0, LOG_MAIN|LOG_PANIC,
2198 "<%s>: failed to expand transport's tls_sni value: %s",
2199 sx->addrlist->address, expand_string_message);
2201 # ifdef SUPPORT_DANE
2202 if ( (continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni)
2203 && continue_proxy_dane == sx->conn_args.dane)
2205 tls_out.sni = US sni;
2206 if ((tls_out.dane_verified = continue_proxy_dane))
2207 sx->conn_args.host->dnssec = DS_YES;
2210 if ((continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni))
2211 tls_out.sni = US sni;
2216 debug_printf("Closing proxied-TLS connection due to SNI mismatch\n");
2218 smtp_debug_cmd(US"QUIT", 0);
2219 write(0, "QUIT\r\n", 6);
2221 continue_hostname = continue_proxy_cipher = NULL;
2222 f.continue_more = FALSE;
2223 continue_sequence = 1; /* Unfortunately, this process cannot affect success log
2224 which is done by delivery proc. Would have to pass this
2225 back through reporting pipe. */
2228 #endif /*!DISABLE_TLS*/
2230 /* Make a connection to the host if this isn't a continued delivery, and handle
2231 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2232 specially so they can be identified for retries. */
2234 if (!continue_hostname)
2237 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2239 /* Arrange to report to calling process this is a new connection */
2241 clearflag(sx->first_addr, af_cont_conn);
2242 setflag(sx->first_addr, af_new_conn);
2244 /* Get the actual port the connection will use, into sx->conn_args.host */
2246 smtp_port_for_connect(sx->conn_args.host, sx->port);
2249 /* Do TLSA lookup for DANE */
2251 tls_out.dane_verified = FALSE;
2252 tls_out.tlsa_usage = 0;
2254 if (sx->conn_args.host->dnssec == DS_YES)
2257 if ((rc = check_force_dane_conn(sx, ob)) != OK)
2260 else if (sx->dane_required)
2262 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2263 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2264 FAIL, FALSE, &sx->delivery_start);
2265 # ifndef DISABLE_EVENT
2266 (void) event_raise(sx->conn_args.tblock->event_action,
2267 US"dane:fail", US"dane-required", NULL);
2274 /* Make the TCP connection */
2276 sx->cctx.tls_ctx = NULL;
2277 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2278 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2279 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom =
2281 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2282 #ifndef DISABLE_CLIENT_CMD_LOG
2283 client_cmd_log = NULL;
2286 #ifndef DISABLE_PIPE_CONNECT
2287 if ( verify_check_given_host(CUSS &ob->hosts_pipe_connect,
2288 sx->conn_args.host) == OK)
2290 /* We don't find out the local ip address until the connect, so if
2291 the helo string might use it avoid doing early-pipelining. */
2294 || sx->conn_args.interface
2295 || !Ustrstr(sx->helo_data, "$sending_ip_address")
2296 || Ustrstr(sx->helo_data, "def:sending_ip_address")
2299 sx->early_pipe_ok = TRUE;
2300 if ( read_ehlo_cache_entry(sx)
2301 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2304 debug_printf("Using cached cleartext PIPECONNECT\n");
2305 sx->early_pipe_active = TRUE;
2306 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2309 else DEBUG(D_transport)
2310 debug_printf("helo needs $sending_ip_address; avoid early-pipelining\n");
2313 if (sx->early_pipe_active)
2315 sx->outblock.conn_args = &sx->conn_args;
2316 (void) smtp_boundsock(&sx->conn_args);
2321 blob lazy_conn = {.data = NULL};
2322 /* For TLS-connect, a TFO lazy-connect is useful since the Client Hello
2323 can go on the TCP SYN. */
2325 if ((sx->cctx.sock = smtp_connect(&sx->conn_args,
2326 sx->smtps ? &lazy_conn : NULL)) < 0)
2328 set_errno_nohost(sx->addrlist,
2329 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2330 sx->verify ? US strerror(errno) : NULL,
2331 DEFER, FALSE, &sx->delivery_start);
2332 sx->send_quit = FALSE;
2336 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2340 /* Expand the greeting message while waiting for the initial response. (Makes
2341 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2342 delayed till here so that $sending_ip_address and $sending_port are set.
2343 Those will be known even for a TFO lazy-connect, having been set by the bind().
2344 For early-pipe, we are ok if binding to a local interface; otherwise (if
2345 $sending_ip_address is seen in helo_data) we disabled early-pipe above. */
2348 if (!(sx->helo_data = expand_string(sx->helo_data)))
2350 log_write(0, LOG_MAIN|LOG_PANIC,
2351 "<%s>: failed to expand transport's helo_data value for callout: %s",
2352 sx->addrlist->address, expand_string_message);
2357 expand_string_message = NULL;
2358 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2359 &expand_string_message)),
2360 expand_string_message)
2362 log_write(0, LOG_MAIN|LOG_PANIC,
2363 "<%s>: failed to expand transport's helo_data value for callout: %s",
2364 sx->addrlist->address, expand_string_message);
2366 sx->helo_data = NULL;
2370 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2371 is nevertheless a reasonably clean way of programming this kind of logic,
2372 where you want to escape on any error. */
2376 #ifndef DISABLE_PIPE_CONNECT
2377 if (sx->early_pipe_active)
2379 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2380 sx->outblock.cmd_count = 1;
2385 if (!smtp_reap_banner(sx))
2386 goto RESPONSE_FAILED;
2389 #ifndef DISABLE_EVENT
2392 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2393 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2394 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer, NULL);
2397 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2398 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2399 DEFER, FALSE, &sx->delivery_start);
2406 /* Now check if the helo_data expansion went well, and sign off cleanly if
2411 message = string_sprintf("failed to expand helo_data: %s",
2412 expand_string_message);
2413 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2419 /** Debugging without sending a message
2420 sx->addrlist->transport_return = DEFER;
2424 /* Errors that occur after this point follow an SMTP command, which is
2425 left in big_buffer by smtp_write_command() for use in error messages. */
2427 smtp_command = big_buffer;
2429 /* Tell the remote who we are...
2431 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2432 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2433 greeting is of this form. The assumption was that the far end supports it
2434 properly... but experience shows that there are some that give 5xx responses,
2435 even though the banner includes "ESMTP" (there's a bloody-minded one that
2436 says "ESMTP not spoken here"). Cope with that case.
2438 September 2000: Time has passed, and it seems reasonable now to always send
2439 EHLO at the start. It is also convenient to make the change while installing
2442 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2443 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2444 would be no way to send out the mails, so there is now a host list
2445 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2446 PIPELINING problem as well. Maybe it can also be useful to cure other
2447 problems with broken servers.
2449 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2450 Then somebody tried it with a Microsoft mailer... It seems that all other
2451 mailers use upper case for some reason (the RFC is quite clear about case
2452 independence) so, for peace of mind, I gave in. */
2454 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2456 /* Alas; be careful, since this goto is not an error-out, so conceivably
2457 we might set data between here and the target which we assume to exist
2458 and be usable. I can see this coming back to bite us. */
2462 smtp_peer_options |= OPTION_TLS;
2463 suppress_tls = FALSE;
2464 ob->tls_tempfail_tryclear = FALSE;
2465 smtp_command = US"SSL-on-connect";
2472 if (smtp_write_command(sx,
2473 #ifndef DISABLE_PIPE_CONNECT
2474 sx->early_pipe_active ? SCMD_BUFFER :
2477 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2479 sx->esmtp_sent = TRUE;
2481 #ifndef DISABLE_PIPE_CONNECT
2482 if (sx->early_pipe_active)
2484 sx->pending_EHLO = TRUE;
2486 /* If we have too many authenticators to handle and might need to AUTH
2487 for this transport, pipeline no further as we will need the
2488 list of auth methods offered. Reap the banner and EHLO. */
2490 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2491 && f.smtp_in_early_pipe_no_auth)
2493 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2494 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2496 if (sync_responses(sx, 2, 0) != 0)
2499 debug_printf("failed reaping pipelined cmd responses\n");
2500 goto RESPONSE_FAILED;
2502 sx->early_pipe_active = FALSE;
2507 if (!smtp_reap_ehlo(sx))
2508 goto RESPONSE_FAILED;
2512 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2514 #ifndef DISABLE_PIPE_CONNECT
2515 if (!sx->early_pipe_active)
2520 int n = sizeof(sx->buffer);
2521 uschar * rsp = sx->buffer;
2523 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer) + 1) < sizeof(sx->buffer)/2)
2524 { rsp = sx->buffer + n; n = sizeof(sx->buffer) - n; }
2526 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2528 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2529 #ifdef EXPERIMENTAL_DSN_INFO
2530 sx->helo_response = string_copy(rsp);
2534 /* Handle special logging for a closed connection after HELO
2535 when had previously sent EHLO */
2537 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2539 errno = ERRNO_SMTPCLOSED;
2540 goto EHLOHELO_FAILED;
2542 memmove(sx->buffer, rsp, Ustrlen(rsp));
2543 goto RESPONSE_FAILED;
2547 if (sx->esmtp || sx->lmtp)
2549 #ifndef DISABLE_PIPE_CONNECT
2550 if (!sx->early_pipe_active)
2553 sx->peer_offered = ehlo_response(sx->buffer,
2554 OPTION_TLS /* others checked later */
2555 #ifndef DISABLE_PIPE_CONNECT
2556 | (sx->early_pipe_ok
2558 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2567 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2568 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2570 ehlo_response_limits_read(sx);
2571 ehlo_response_limits_apply(sx);
2574 #ifndef DISABLE_PIPE_CONNECT
2575 if (sx->early_pipe_ok)
2577 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2579 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2580 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2582 DEBUG(D_transport) debug_printf("PIPECONNECT usable in future for this IP\n");
2583 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2584 write_ehlo_cache_entry(sx);
2588 ehlo_response_lbserver(sx, ob);
2591 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2594 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2599 /* For continuing deliveries down the same channel, having re-exec'd the socket
2600 is the standard input; for a socket held open from verify it is recorded
2601 in the cutthrough context block. Either way we don't need to redo EHLO here
2602 (but may need to do so for TLS - see below).
2603 Set up the pointer to where subsequent commands will be left, for
2604 error messages. Note that smtp_peer_options will have been
2605 set from the command line if they were set in the process that passed the
2608 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2609 as the continue goes via transport_pass_socket() and doublefork and exec.
2610 It does not wait. Unclear how we keep separate host's responses
2611 separate - we could match up by host ip+port as a bodge. */
2615 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2617 sx->cctx = cutthrough.cctx;
2618 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2622 sx->cctx.sock = 0; /* stdin */
2623 sx->cctx.tls_ctx = NULL;
2624 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2626 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2627 smtp_command = big_buffer;
2628 sx->peer_offered = smtp_peer_options;
2629 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2630 /* Limits passed by cmdline over exec. */
2631 ehlo_limits_apply(sx,
2632 sx->peer_limit_mail = continue_limit_mail,
2633 sx->peer_limit_rcpt = continue_limit_rcpt,
2634 sx->peer_limit_rcptdom = continue_limit_rcptdom);
2636 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2638 /* For a continued connection with TLS being proxied for us, or a
2639 held-open verify connection with TLS, nothing more to do. */
2641 if ( continue_proxy_cipher
2642 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2643 && cutthrough.is_tls)
2646 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2647 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2648 continue_proxy_cipher ? "proxied" : "verify conn with");
2651 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2654 /* If TLS is available on this connection, whether continued or not, attempt to
2655 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2656 send another EHLO - the server may give a different answer in secure mode. We
2657 use a separate buffer for reading the response to STARTTLS so that if it is
2658 negative, the original EHLO data is available for subsequent analysis, should
2659 the client not be required to use TLS. If the response is bad, copy the buffer
2660 for error analysis. */
2663 if ( smtp_peer_options & OPTION_TLS
2665 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2667 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2670 uschar buffer2[4096];
2672 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2675 #ifndef DISABLE_PIPE_CONNECT
2676 /* If doing early-pipelining reap the banner and EHLO-response but leave
2677 the response for the STARTTLS we just sent alone. On fail, assume wrong
2678 cached capability and retry with the pipelining disabled. */
2680 if (sx->early_pipe_active)
2682 if (sync_responses(sx, 2, 0) != 0)
2685 debug_printf("failed reaping pipelined cmd responses\n");
2686 close(sx->cctx.sock);
2688 sx->early_pipe_active = FALSE;
2689 goto PIPE_CONNECT_RETRY;
2694 /* If there is an I/O error, transmission of this message is deferred. If
2695 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2696 false, we also defer. However, if there is a temporary rejection of STARTTLS
2697 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2698 STARTTLS, we carry on. This means we will try to send the message in clear,
2699 unless the host is in hosts_require_tls (tested below). */
2701 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2705 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2708 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2709 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2710 goto RESPONSE_FAILED;
2714 /* STARTTLS accepted: try to negotiate a TLS session. */
2719 sx->conn_args.sending_ip_address = sending_ip_address;
2720 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2722 /* TLS negotiation failed; give an error. From outside, this function may
2723 be called again to try in clear on a new connection, if the options permit
2724 it for this host. */
2726 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2728 # ifdef SUPPORT_DANE
2729 if (sx->conn_args.dane)
2731 log_write(0, LOG_MAIN,
2732 "DANE attempt failed; TLS connection to %s [%s]: %s",
2733 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2734 # ifndef DISABLE_EVENT
2735 (void) event_raise(sx->conn_args.tblock->event_action,
2736 US"dane:fail", US"validation-failure", NULL); /* could do with better detail */
2741 errno = ERRNO_TLSFAILURE;
2742 message = string_sprintf("TLS session: %s", tls_errstr);
2743 sx->send_quit = FALSE;
2746 sx->send_tlsclose = TRUE;
2748 /* TLS session is set up. Check the inblock fill level. If there is
2749 content then as we have not yet done a tls read it must have arrived before
2750 the TLS handshake, in-clear. That violates the sync requirement of the
2751 STARTTLS RFC, so fail. */
2753 if (sx->inblock.ptr != sx->inblock.ptrend)
2757 int i = sx->inblock.ptrend - sx->inblock.ptr;
2758 debug_printf("unused data in input buffer after ack for STARTTLS:\n"
2760 i > 100 ? 100 : i, sx->inblock.ptr, i > 100 ? "..." : "");
2762 tls_errstr = US"synch error before connect";
2763 goto TLS_CONN_FAILED;
2766 smtp_peer_options_wrap = smtp_peer_options;
2767 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2768 if (addr->transport_return == PENDING_DEFER)
2770 addr->cipher = tls_out.cipher;
2771 addr->ourcert = tls_out.ourcert;
2772 addr->peercert = tls_out.peercert;
2773 addr->peerdn = tls_out.peerdn;
2774 addr->ocsp = tls_out.ocsp;
2775 addr->tlsver = tls_out.ver;
2780 /* if smtps, we'll have smtp_command set to something else; always safe to
2782 smtp_command = big_buffer;
2784 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2785 helo_data is null, we are dealing with a connection that was passed from
2786 another process, and so we won't have expanded helo_data above. We have to
2787 expand it here. $sending_ip_address and $sending_port are set up right at the
2788 start of the Exim process (in exim.c). */
2790 if (tls_out.active.sock >= 0)
2792 uschar * greeting_cmd;
2794 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2796 uschar *message = string_sprintf("failed to expand helo_data: %s",
2797 expand_string_message);
2798 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2803 #ifndef DISABLE_PIPE_CONNECT
2804 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2805 We're unlikely to get the group sent and delivered before the server sends its
2806 banner, but it's still worth sending as a group.
2807 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2810 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2812 sx->peer_offered = sx->ehlo_resp.crypted_features;
2813 if ((sx->early_pipe_active =
2814 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2815 DEBUG(D_transport) debug_printf("Using cached crypted PIPECONNECT\n");
2818 #ifdef EXPERIMMENTAL_ESMTP_LIMITS
2819 /* As we are about to send another EHLO, forget any LIMITS received so far. */
2820 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom = 0;
2821 if ((sx->max_mail = sx->conn_args.tblock->connection_max_message) == 0) sx->max_mail = 999999;
2822 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
2823 sx->single_rcpt_domain = FALSE;
2826 /* For SMTPS we need to wait for the initial OK response. */
2828 #ifndef DISABLE_PIPE_CONNECT
2829 if (sx->early_pipe_active)
2831 sx->pending_BANNER = TRUE;
2832 sx->outblock.cmd_count = 1;
2836 if (!smtp_reap_banner(sx))
2837 goto RESPONSE_FAILED;
2840 greeting_cmd = US"LHLO";
2842 greeting_cmd = US"EHLO";
2845 greeting_cmd = US"HELO";
2847 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2850 if (smtp_write_command(sx,
2851 #ifndef DISABLE_PIPE_CONNECT
2852 sx->early_pipe_active ? SCMD_BUFFER :
2855 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2858 #ifndef DISABLE_PIPE_CONNECT
2859 if (sx->early_pipe_active)
2860 sx->pending_EHLO = TRUE;
2864 if (!smtp_reap_ehlo(sx))
2867 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2868 cert late, under TLS1.3 - which means here; the first time we try to
2869 receive crypted data. Treat it as if it was a connect-time failure.
2870 See also the early-pipe equivalent... which will be hard; every call
2871 to sync_responses will need to check the result.
2872 It would be nicer to have GnuTLS check the cert during the handshake.
2873 Can it do that, with all the flexibility we need? */
2875 tls_errstr = US"error on first read";
2876 goto TLS_CONN_FAILED;
2879 goto RESPONSE_FAILED;
2881 smtp_peer_options = 0;
2885 /* If the host is required to use a secure channel, ensure that we
2889 # ifdef SUPPORT_DANE
2890 || sx->conn_args.dane
2892 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2895 errno = ERRNO_TLSREQUIRED;
2896 message = string_sprintf("a TLS session is required, but %s",
2897 smtp_peer_options & OPTION_TLS
2898 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2899 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2900 if (sx->conn_args.dane)
2901 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2902 smtp_peer_options & OPTION_TLS
2903 ? US"validation-failure" /* could do with better detail */
2904 : US"starttls-not-supported",
2909 #endif /*DISABLE_TLS*/
2911 /* If TLS is active, we have just started it up and re-done the EHLO command,
2912 so its response needs to be analyzed. If TLS is not active and this is a
2913 continued session down a previously-used socket, we haven't just done EHLO, so
2916 if ( !continue_hostname
2918 || tls_out.active.sock >= 0
2922 if (sx->esmtp || sx->lmtp)
2924 #ifndef DISABLE_PIPE_CONNECT
2925 if (!sx->early_pipe_active)
2928 sx->peer_offered = ehlo_response(sx->buffer,
2930 #ifndef DISABLE_PIPE_CONNECT
2931 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2932 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2933 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2934 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2938 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2941 # ifdef SUPPORT_I18N
2942 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2943 /*XXX if we hand peercaps on to continued-conn processes,
2944 must not depend on this addr */
2948 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2951 #ifndef DISABLE_PIPE_CONNECT
2952 if (tls_out.active.sock >= 0)
2953 sx->ehlo_resp.crypted_features = sx->peer_offered;
2956 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2957 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2959 ehlo_response_limits_read(sx);
2960 ehlo_response_limits_apply(sx);
2965 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2966 lmtp_ignore_quota option was set. */
2968 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2970 /* If the response to EHLO specified support for the SIZE parameter, note
2971 this, provided size_addition is non-negative. */
2973 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2975 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2976 the current host, esmtp will be false, so PIPELINING can never be used. If
2977 the current host matches hosts_avoid_pipelining, don't do it. */
2979 if ( sx->peer_offered & OPTION_PIPE
2980 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2981 smtp_peer_options |= OPTION_PIPE;
2983 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2984 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2986 if ( sx->peer_offered & OPTION_CHUNKING
2987 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) == OK)
2988 smtp_peer_options |= OPTION_CHUNKING;
2990 if (smtp_peer_options & OPTION_CHUNKING)
2991 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2993 #ifndef DISABLE_PRDR
2994 if ( sx->peer_offered & OPTION_PRDR
2995 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) == OK)
2996 smtp_peer_options |= OPTION_PRDR;
2998 if (smtp_peer_options & OPTION_PRDR)
2999 DEBUG(D_transport) debug_printf("PRDR usable\n");
3002 /* Note if the server supports DSN */
3003 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
3004 DEBUG(D_transport) debug_printf("%susing DSN\n",
3005 sx->peer_offered & OPTION_DSN ? "" : "not ");
3007 #ifndef DISABLE_PIPE_CONNECT
3008 if ( sx->early_pipe_ok
3009 && !sx->early_pipe_active
3010 && tls_out.active.sock >= 0
3011 && smtp_peer_options & OPTION_PIPE
3012 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
3013 & OPTION_EARLY_PIPE)
3015 DEBUG(D_transport) debug_printf("PIPECONNECT usable in future for this IP\n");
3016 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
3017 write_ehlo_cache_entry(sx);
3021 /* Note if the response to EHLO specifies support for the AUTH extension.
3022 If it has, check that this host is one we want to authenticate to, and do
3023 the business. The host name and address must be available when the
3024 authenticator's client driver is running. */
3026 switch (yield = smtp_auth(sx))
3028 default: goto SEND_QUIT;
3030 case FAIL_SEND: goto SEND_FAILED;
3031 case FAIL: goto RESPONSE_FAILED;
3035 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
3037 /* The setting up of the SMTP call is now complete. Any subsequent errors are
3038 message-specific. */
3040 sx->setting_up = FALSE;
3043 if (sx->addrlist->prop.utf8_msg)
3047 /* If the transport sets a downconversion mode it overrides any set by ACL
3050 if ((s = ob->utf8_downconvert))
3052 if (!(s = expand_string(s)))
3054 message = string_sprintf("failed to expand utf8_downconvert: %s",
3055 expand_string_message);
3056 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
3062 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
3063 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3065 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
3066 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3068 case '-': if (s[1] == '1')
3070 sx->addrlist->prop.utf8_downcvt = FALSE;
3071 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
3077 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
3078 && !sx->addrlist->prop.utf8_downcvt_maybe;
3079 DEBUG(D_transport) if (!sx->utf8_needed)
3080 debug_printf("utf8: %s downconvert\n",
3081 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
3084 /* If this is an international message we need the host to speak SMTPUTF8 */
3085 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
3087 errno = ERRNO_UTF8_FWD;
3088 goto RESPONSE_FAILED;
3090 #endif /*SUPPORT_I18N*/
3099 if (errno == ECONNREFUSED) /* first-read error on a TFO conn */
3101 /* There is a testing facility for simulating a connection timeout, as I
3102 can't think of any other way of doing this. It converts a connection
3103 refused into a timeout if the timeout is set to 999999. This is done for
3104 a 3whs connection in ip_connect(), but a TFO connection does not error
3105 there - instead it gets ECONNREFUSED on the first data read. Tracking
3106 that a TFO really was done is too hard, or we would set a
3107 sx->pending_conn_done bit and test that in smtp_reap_banner() and
3108 smtp_reap_ehlo(). That would let us also add the conn-timeout to the
3111 if (f.running_in_test_harness && ob->connect_timeout == 999999)
3113 set_errno_nohost(sx->addrlist,
3114 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
3115 sx->verify ? US strerror(errno) : NULL,
3116 DEFER, FALSE, &sx->delivery_start);
3117 sx->send_quit = FALSE;
3121 /* really an error on an SMTP read */
3123 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
3124 sx->buffer, &code, &message, &pass_message);
3130 message = US string_sprintf("smtp send to %s [%s] failed: %s",
3131 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
3132 sx->send_quit = FALSE;
3138 message = string_sprintf("Remote host closed connection in response to %s"
3139 " (EHLO response was: %s)", smtp_command, sx->buffer);
3140 sx->send_quit = FALSE;
3144 /* This label is jumped to directly when a TLS negotiation has failed,
3145 or was not done for a host for which it is required. Values will be set
3146 in message and errno, and setting_up will always be true. Treat as
3147 a temporary error. */
3151 code = '4', yield = DEFER;
3155 /* The failure happened while setting up the call; see if the failure was
3156 a 5xx response (this will either be on connection, or following HELO - a 5xx
3157 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
3158 fail all addresses, as this host is never going to accept them. For other
3159 errors during setting up (timeouts or whatever), defer all addresses, and
3160 yield DEFER, so that the host is not tried again for a while.
3162 XXX This peeking for another host feels like a layering violation. We want
3163 to note the host as unusable, but down here we shouldn't know if this was
3164 the last host to try for the addr(list). Perhaps the upper layer should be
3165 the one to do set_errno() ? The problem is that currently the addr is where
3166 errno etc. are stashed, but until we run out of hosts to try the errors are
3167 host-specific. Maybe we should enhance the host_item definition? */
3170 sx->ok = FALSE; /* For when reached by GOTO */
3171 set_errno(sx->addrlist, errno, message,
3172 sx->conn_args.host->next
3176 || errno == ERRNO_UTF8_FWD
3180 errno == ECONNREFUSED ? NULL : sx->conn_args.host,
3181 #ifdef EXPERIMENTAL_DSN_INFO
3182 sx->smtp_greeting, sx->helo_response,
3184 &sx->delivery_start);
3191 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
3194 if (sx->cctx.tls_ctx)
3196 if (sx->send_tlsclose)
3198 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
3199 sx->send_tlsclose = FALSE;
3201 sx->cctx.tls_ctx = NULL;
3205 /* Close the socket, and return the appropriate value, first setting
3206 works because the NULL setting is passed back to the calling process, and
3207 remote_max_parallel is forced to 1 when delivering over an existing connection,
3210 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3213 shutdown(sx->cctx.sock, SHUT_WR);
3214 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
3215 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
3216 i--; /* drain socket */
3217 sx->send_quit = FALSE;
3219 (void)close(sx->cctx.sock);
3222 #ifndef DISABLE_EVENT
3223 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL, NULL);
3226 smtp_debug_cmd_report();
3227 continue_transport = NULL;
3228 continue_hostname = NULL;
3235 /* Create the string of options that will be appended to the MAIL FROM:
3236 in the connection context buffer */
3239 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
3241 uschar * p = sx->buffer;
3242 address_item * addr;
3247 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
3248 send it, adding something to the message size to allow for imprecision
3249 and things that get added en route. Exim keeps the number of lines
3250 in a message, so we can give an accurate value for the original message, but we
3251 need some additional to handle added headers. (Double "." characters don't get
3252 included in the count.) */
3254 if ( message_size > 0
3255 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
3257 /*XXX problem here under spool_files_wireformat?
3258 Or just forget about lines? Or inflate by a fixed proportion? */
3260 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
3264 #ifndef DISABLE_PRDR
3265 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
3268 sx->prdr_active = FALSE;
3269 if (smtp_peer_options & OPTION_PRDR)
3270 for (address_item * addr = addrlist; addr; addr = addr->next)
3271 if (addr->transport_return == PENDING_DEFER)
3273 for (addr = addr->next; addr; addr = addr->next)
3274 if (addr->transport_return == PENDING_DEFER)
3275 { /* at least two recipients to send */
3276 sx->prdr_active = TRUE;
3277 sprintf(CS p, " PRDR"); p += 5;
3285 /* If it supports internationalised messages, and this meesage need that,
3288 if ( sx->peer_offered & OPTION_UTF8
3289 && addrlist->prop.utf8_msg
3290 && !addrlist->prop.utf8_downcvt
3292 Ustrcpy(p, US" SMTPUTF8"), p += 9;
3295 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3296 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3297 addr && address_count < sx->max_rcpt; /*XXX maybe also || sx->single_rcpt_domain ? */
3298 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3301 if (!(addr->dsn_flags & rf_dsnlasthop))
3303 sx->dsn_all_lasthop = FALSE;
3308 /* Add any DSN flags to the mail command */
3310 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3312 if (dsn_ret == dsn_ret_hdrs)
3313 { Ustrcpy(p, US" RET=HDRS"); p += 9; }
3314 else if (dsn_ret == dsn_ret_full)
3315 { Ustrcpy(p, US" RET=FULL"); p += 9; }
3319 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3324 /* If an authenticated_sender override has been specified for this transport
3325 instance, expand it. If the expansion is forced to fail, and there was already
3326 an authenticated_sender for this message, the original value will be used.
3327 Other expansion failures are serious. An empty result is ignored, but there is
3328 otherwise no check - this feature is expected to be used with LMTP and other
3329 cases where non-standard addresses (e.g. without domains) might be required. */
3331 return smtp_mail_auth_str(sx, p, addrlist) ? ERROR : OK;
3336 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3338 uschar * p = sx->buffer;
3341 /* Add any DSN flags to the rcpt command */
3343 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3345 if (addr->dsn_flags & rf_dsnflags)
3349 Ustrcpy(p, US" NOTIFY=");
3351 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3353 if (!first) *p++ = ',';
3355 Ustrcpy(p, rf_names[i]);
3360 if (addr->dsn_orcpt)
3362 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3373 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3374 -1 MAIL response error
3375 -2 any non-MAIL read i/o error
3376 -3 non-MAIL response timeout
3377 -4 internal error; channel still usable
3382 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3384 address_item * addr;
3385 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3386 address_item * restart_addr = NULL;
3388 int address_count, pipe_limit;
3391 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3397 /* From here until we send the DATA command, we can make use of PIPELINING
3398 if the server host supports it. The code has to be able to check the responses
3399 at any point, for when the buffer fills up, so we write it totally generally.
3400 When PIPELINING is off, each command written reports that it has flushed the
3403 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3406 uschar * s = sx->from_addr;
3408 uschar * errstr = NULL;
3410 /* If we must downconvert, do the from-address here. Remember we had to
3411 for the to-addresses (done below), and also (ugly) for re-doing when building
3412 the delivery log line. */
3414 if ( sx->addrlist->prop.utf8_msg
3415 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3418 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3420 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, &sx->delivery_start);
3424 setflag(sx->addrlist, af_utf8_downcvt);
3428 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3429 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3432 mail_command = string_copy(big_buffer); /* Save for later error message */
3436 case -1: /* Transmission error */
3439 case +1: /* Cmd was sent */
3440 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3441 (SOB sx->conn_args.ob)->command_timeout))
3443 if (errno == 0 && sx->buffer[0] == '4')
3445 errno = ERRNO_MAIL4XX;
3446 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3450 sx->pending_MAIL = FALSE;
3453 /* otherwise zero: command queued for pipeline */
3456 /* Pass over all the relevant recipient addresses for this host, which are the
3457 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3458 several before we have to read the responses for those seen so far. This
3459 checking is done by a subroutine because it also needs to be done at the end.
3460 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3461 the next one if not all are sent.
3463 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3464 last address because we want to abort if any recipients have any kind of
3465 problem, temporary or permanent. We know that all recipient addresses will have
3466 the PENDING_DEFER status, because only one attempt is ever made, and we know
3467 that max_rcpt will be large, so all addresses will be done at once.
3469 For verify we flush the pipeline after any (the only) rcpt address. */
3471 for (addr = sx->first_addr, address_count = 0, pipe_limit = 100;
3472 addr && address_count < sx->max_rcpt;
3473 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3479 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3480 if ( sx->single_rcpt_domain /* restriction on domains */
3481 && address_count > 0 /* not first being sent */
3482 && Ustrcmp(addr->domain, sx->first_addr->domain) != 0 /* dom diff from first */
3485 DEBUG(D_transport) debug_printf("skipping different domain %s\n", addr->domain);
3487 /* Ensure the smtp-response reaper does not think the address had a RCPT
3488 command sent for it. Reset to PENDING_DEFER in smtp_deliver(), where we
3489 goto SEND_MESSAGE. */
3491 addr->transport_return = SKIP;
3492 if (!restart_addr) restart_addr = addr; /* note restart point */
3493 continue; /* skip this one */
3497 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3498 ? dsn_support_yes : dsn_support_no;
3501 if (pipe_limit-- <= 0)
3502 { no_flush = FALSE; pipe_limit = 100; }
3504 no_flush = pipelining_active && !sx->verify
3505 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3507 build_rcptcmd_options(sx, addr);
3509 /* Now send the RCPT command, and process outstanding responses when
3510 necessary. After a timeout on RCPT, we just end the function, leaving the
3511 yield as OK, because this error can often mean that there is a problem with
3512 just one address, so we don't want to delay the host. */
3514 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3517 if ( testflag(sx->addrlist, af_utf8_downcvt)
3518 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3521 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3522 errno = ERRNO_EXPANDFAIL;
3523 return -5; /*XXX too harsh? */
3527 cmds_sent = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3528 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3530 if (cmds_sent < 0) return -5;
3533 switch(sync_responses(sx, cmds_sent, 0))
3535 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3536 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3539 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3540 if (!sx->lmtp) /* can't tell about progress yet */
3541 sx->completed_addr = TRUE;
3542 case 0: /* No 2xx or 5xx, but no probs */
3543 /* If any RCPT got a 452 response then next_addr has been updated
3544 for restarting with a new MAIL on the same connection. Send no more
3545 RCPTs for this MAIL. */
3549 DEBUG(D_transport) debug_printf("seen 452 too-many-rcpts\n");
3550 sx->RCPT_452 = FALSE;
3551 /* sx->next_addr has been reset for fast_retry */
3556 case -1: return -3; /* Timeout on RCPT */
3557 case -2: return -2; /* non-MAIL read i/o error */
3558 default: return -1; /* any MAIL error */
3560 #ifndef DISABLE_PIPE_CONNECT
3561 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3562 case -5: return -1; /* TLS first-read error */
3566 } /* Loop for next address */
3568 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3569 sx->next_addr = restart_addr ? restart_addr : addr;
3571 sx->next_addr = addr;
3578 /*****************************************************
3579 * Proxy TLS connection for another transport process *
3580 ******************************************************/
3582 Close the unused end of the pipe, fork once more, then use the given buffer
3583 as a staging area, and select on both the given fd and the TLS'd client-fd for
3584 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3585 Do blocking full-size writes, and reads under a timeout. Once both input
3586 channels are closed, exit the process.
3590 buf space to use for buffering
3591 bufsiz size of buffer
3592 pfd pipe filedescriptor array; [0] is comms to proxied process
3593 timeout per-read timeout, seconds
3594 host hostname of remote
3600 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3601 int timeout, const uschar * host)
3603 struct pollfd p[2] = {{.fd = tls_out.active.sock, .events = POLLIN},
3604 {.fd = pfd[0], .events = POLLIN}};
3606 BOOL send_tls_shutdown = TRUE;
3609 if ((rc = exim_fork(US"tls-proxy")))
3610 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3612 set_process_info("proxying TLS connection for continued transport to %s\n", host);
3616 time_t time_left = timeout;
3617 time_t time_start = time(NULL);
3622 rc = poll(p, 2, time_left * 1000);
3624 if (rc < 0 && errno == EINTR)
3625 if ((time_left -= time(NULL) - time_start) > 0) continue;
3629 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3633 /* For errors where not readable, bomb out */
3635 if (p[0].revents & POLLERR || p[1].revents & POLLERR)
3637 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3638 p[0].revents & POLLERR ? "tls" : "proxy");
3639 if (!(p[0].revents & POLLIN || p[1].events & POLLIN))
3641 DEBUG(D_transport) debug_printf("- but also readable; no exit yet\n");
3644 while (rc < 0 || !(p[0].revents & POLLIN || p[1].revents & POLLIN));
3646 /* handle inbound data */
3647 if (p[0].revents & POLLIN)
3648 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0) /* Expect -1 for EOF; */
3649 { /* that reaps the TLS Close Notify record */
3651 shutdown(pfd[0], SHUT_WR);
3655 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3656 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3658 /* Handle outbound data. We cannot combine payload and the TLS-close
3659 due to the limitations of the (pipe) channel feeding us. Maybe use a unix-domain
3661 if (p[1].revents & POLLIN)
3662 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3666 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
3667 (void) setsockopt(tls_out.active.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
3669 tls_shutdown_wr(ct_ctx);
3670 send_tls_shutdown = FALSE;
3671 shutdown(tls_out.active.sock, SHUT_WR);
3674 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3675 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3678 while (p[0].fd >= 0 || p[1].fd >= 0);
3681 if (send_tls_shutdown) tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3683 testharness_pause_ms(100); /* let logging complete */
3684 exim_exit(EXIT_SUCCESS);
3689 /*************************************************
3690 * Deliver address list to given host *
3691 *************************************************/
3693 /* If continue_hostname is not null, we get here only when continuing to
3694 deliver down an existing channel. The channel was passed as the standard
3695 input. TLS is never active on a passed channel; the previous process either
3696 closes it down before passing the connection on, or inserts a TLS-proxy
3697 process and passes on a cleartext conection.
3699 Otherwise, we have to make a connection to the remote host, and do the
3700 initial protocol exchange.
3702 When running as an MUA wrapper, if the sender or any recipient is rejected,
3703 temporarily or permanently, we force failure for all recipients.
3706 addrlist chain of potential addresses to deliver; only those whose
3707 transport_return field is set to PENDING_DEFER are currently
3708 being processed; others should be skipped - they have either
3709 been delivered to an earlier host or IP address, or been
3710 failed by one of them.
3711 host host to deliver to
3712 host_af AF_INET or AF_INET6
3713 defport default TCP/IP port to use if host does not specify, in host
3715 interface interface to bind to, or NULL
3716 tblock transport instance block
3717 message_defer set TRUE if yield is OK, but all addresses were deferred
3718 because of a non-recipient, non-host failure, that is, a
3719 4xx response to MAIL FROM, DATA, or ".". This is a defer
3720 that is specific to the message.
3721 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3722 a second attempt after TLS initialization fails
3724 Returns: OK - the connection was made and the delivery attempted;
3725 the result for each address is in its data block.
3726 DEFER - the connection could not be made, or something failed
3727 while setting up the SMTP session, or there was a
3728 non-message-specific error, such as a timeout.
3729 ERROR - a filter command is specified for this transport,
3730 and there was a problem setting it up; OR helo_data
3731 or add_headers or authenticated_sender is specified
3732 for this transport, and the string failed to expand
3734 For all non-OK returns the first addr of the list carries the
3735 time taken for the attempt.
3739 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3740 uschar *interface, transport_instance *tblock,
3741 BOOL *message_defer, BOOL suppress_tls)
3743 smtp_transport_options_block * ob = SOB tblock->options_block;
3748 uschar *message = NULL;
3749 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3750 smtp_context * sx = store_get(sizeof(*sx), GET_TAINTED); /* tainted, for the data buffers */
3751 BOOL pass_message = FALSE;
3752 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3753 BOOL mail_limit = FALSE;
3758 BOOL tcw_done = FALSE, tcw = FALSE;
3760 *message_defer = FALSE;
3762 memset(sx, 0, sizeof(*sx));
3763 sx->addrlist = addrlist;
3764 sx->conn_args.host = host;
3765 sx->conn_args.host_af = host_af;
3767 sx->conn_args.interface = interface;
3768 sx->helo_data = NULL;
3769 sx->conn_args.tblock = tblock;
3770 sx->conn_args.sock = -1;
3771 gettimeofday(&sx->delivery_start, NULL);
3772 sx->sync_addr = sx->first_addr = addrlist;
3779 /* Get the channel set up ready for a message, MAIL FROM being the next
3780 SMTP command to send. */
3782 if ((rc = smtp_setup_conn(sx, suppress_tls)) != OK)
3784 timesince(&addrlist->delivery_time, &sx->delivery_start);
3790 /* If the connection used DANE, ignore for now any addresses with incompatible
3791 domains. The SNI has to be the domain. Arrange a whole new TCP conn later,
3792 just in case only TLS isn't enough. */
3794 if (sx->conn_args.dane)
3796 const uschar * dane_domain = sx->first_addr->domain;
3798 for (address_item * a = sx->first_addr->next; a; a = a->next)
3799 if ( a->transport_return == PENDING_DEFER
3800 && Ustrcmp(dane_domain, a->domain) != 0)
3802 DEBUG(D_transport) debug_printf("DANE: holding %s for later\n", a->domain);
3804 a->transport_return = DANE;
3809 /* If there is a filter command specified for this transport, we can now
3810 set it up. This cannot be done until the identity of the host is known. */
3812 if (tblock->filter_command)
3814 transport_filter_timeout = tblock->filter_timeout;
3816 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3819 if (!transport_set_up_command(&transport_filter_argv,
3820 tblock->filter_command, TRUE, DEFER, addrlist, FALSE,
3821 string_sprintf("%.50s transport filter", tblock->name), NULL))
3823 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3824 FALSE, &sx->delivery_start);
3829 if ( transport_filter_argv
3830 && *transport_filter_argv
3831 && **transport_filter_argv
3832 && smtp_peer_options & OPTION_CHUNKING
3833 #ifndef DISABLE_DKIM
3834 /* When dkim signing, chunking is handled even with a transport-filter */
3835 && !(ob->dkim.dkim_private_key && ob->dkim.dkim_domain && ob->dkim.dkim_selector)
3836 && !ob->dkim.force_bodyhash
3840 smtp_peer_options &= ~OPTION_CHUNKING;
3841 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3845 /* For messages that have more than the maximum number of envelope recipients,
3846 we want to send several transactions down the same SMTP connection. (See
3847 comments in deliver.c as to how this reconciles, heuristically, with
3848 remote_max_parallel.) This optimization was added to Exim after the following
3849 code was already working. The simplest way to put it in without disturbing the
3850 code was to use a goto to jump back to this point when there is another
3851 transaction to handle. */
3854 sx->from_addr = return_path;
3855 sx->sync_addr = sx->first_addr;
3857 sx->send_rset = TRUE;
3858 sx->completed_addr = FALSE;
3861 /* If we are a continued-connection-after-verify the MAIL and RCPT
3862 commands were already sent; do not re-send but do mark the addrs as
3863 having been accepted up to RCPT stage. A traditional cont-conn
3864 always has a sequence number greater than one. */
3866 if (continue_hostname && continue_sequence == 1)
3868 /* sx->pending_MAIL = FALSE; */
3870 /* sx->next_addr = NULL; */
3872 for (address_item * addr = addrlist; addr; addr = addr->next)
3873 addr->transport_return = PENDING_OK;
3877 /* Initiate a message transfer. */
3879 switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))
3882 case -1: case -2: goto RESPONSE_FAILED;
3883 case -3: goto END_OFF;
3884 case -4: goto SEND_QUIT;
3885 default: goto SEND_FAILED;
3888 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3889 permanently or temporarily. We should have flushed and synced after the last
3897 for (a = sx->first_addr, cnt = 0; a && cnt < sx->max_rcpt; a = a->next, cnt++)
3898 if (a->transport_return != PENDING_OK)
3900 /*XXX could we find a better errno than 0 here? */
3901 set_errno_nohost(addrlist, 0, a->message, FAIL,
3902 testflag(a, af_pass_message), &sx->delivery_start);
3909 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3910 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3911 have a good recipient buffered up if we are pipelining. We don't want to waste
3912 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3913 are pipelining. The responses are all handled by sync_responses().
3914 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3917 if ( !(smtp_peer_options & OPTION_CHUNKING)
3918 && (sx->ok || (pipelining_active && !mua_wrapper)))
3920 int count = smtp_write_command(sx, SCMD_FLUSH, "DATA\r\n");
3922 if (count < 0) goto SEND_FAILED;
3923 switch(sync_responses(sx, count, sx->ok ? +1 : -1))
3925 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3926 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3929 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3930 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
3931 case 0: break; /* No 2xx or 5xx, but no probs */
3933 case -1: goto END_OFF; /* Timeout on RCPT */
3935 #ifndef DISABLE_PIPE_CONNECT
3936 case -5: /* TLS first-read error */
3937 case -4: HDEBUG(D_transport)
3938 debug_printf("failed reaping pipelined cmd responses\n");
3940 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3942 pipelining_active = FALSE;
3943 data_command = string_copy(big_buffer); /* Save for later error message */
3946 /* If there were no good recipients (but otherwise there have been no
3947 problems), just set ok TRUE, since we have handled address-specific errors
3948 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3949 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3950 well as body. Set the appropriate timeout value to be used for each chunk.
3951 (Haven't been able to make it work using select() for writing yet.) */
3954 && (!(smtp_peer_options & OPTION_CHUNKING) || !pipelining_active))
3956 /* Save the first address of the next batch. */
3957 sx->first_addr = sx->next_addr;
3963 transport_ctx tctx = {
3964 .u = {.fd = sx->cctx.sock}, /*XXX will this need TLS info? */
3967 .check_string = US".",
3968 .escape_string = US"..", /* Escaping strings */
3970 topt_use_crlf | topt_escape_headers
3971 | (tblock->body_only ? topt_no_headers : 0)
3972 | (tblock->headers_only ? topt_no_body : 0)
3973 | (tblock->return_path_add ? topt_add_return_path : 0)
3974 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3975 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3978 /* If using CHUNKING we need a callback from the generic transport
3979 support to us, for the sending of BDAT smtp commands and the reaping
3980 of responses. The callback needs a whole bunch of state so set up
3981 a transport-context structure to be passed around. */
3983 if (smtp_peer_options & OPTION_CHUNKING)
3985 tctx.check_string = tctx.escape_string = NULL;
3986 tctx.options |= topt_use_bdat;
3987 tctx.chunk_cb = smtp_chunk_cmd_callback;
3988 sx->pending_BDAT = FALSE;
3989 sx->good_RCPT = sx->ok;
3991 tctx.smtp_context = sx;
3994 tctx.options |= topt_end_dot;
3996 /* Save the first address of the next batch. */
3997 sx->first_addr = sx->next_addr;
3999 /* Responses from CHUNKING commands go in buffer. Otherwise,
4000 there has not been a response. */
4004 sigalrm_seen = FALSE;
4005 transport_write_timeout = ob->data_timeout;
4006 smtp_command = US"sending data block"; /* For error messages */
4007 DEBUG(D_transport|D_v)
4008 if (smtp_peer_options & OPTION_CHUNKING)
4009 debug_printf(" will write message using CHUNKING\n");
4011 debug_printf(" SMTP>> (writing message)\n");
4012 transport_count = 0;
4014 #ifndef DISABLE_DKIM
4016 # ifdef MEASURE_TIMING
4018 gettimeofday(&t0, NULL);
4020 dkim_exim_sign_init();
4021 # ifdef EXPERIMENTAL_ARC
4023 uschar * s = ob->arc_sign;
4026 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
4028 if (!f.expand_string_forcedfail)
4030 message = US"failed to expand arc_sign";
4037 /* Ask dkim code to hash the body for ARC */
4038 (void) arc_ams_setup_sign_bodyhash();
4039 ob->dkim.force_bodyhash = TRUE;
4044 # ifdef MEASURE_TIMING
4045 report_time_since(&t0, US"dkim_exim_sign_init (delta)");
4050 /* See if we can pipeline QUIT. Reasons not to are
4051 - pipelining not active
4052 - not ok to send quit
4053 - errors in amtp transation responses
4054 - more addrs to send for this message or this host
4055 - this message was being retried
4056 - more messages for this host
4057 If we can, we want the message-write to not flush (the tail end of) its data out. */
4059 if ( sx->pipelining_used
4060 && (sx->ok && sx->completed_addr || smtp_peer_options & OPTION_CHUNKING)
4062 && !(sx->first_addr || f.continue_more)
4063 && f.deliver_firsttime
4066 smtp_compare_t t_compare =
4067 {.tblock = tblock, .current_sender_address = sender_address};
4072 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4073 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4077 transport_check_waiting(tblock->name, host->name,
4078 tblock->connection_max_messages, new_message_id,
4079 (oicf)smtp_are_same_identities, (void*)&t_compare);
4082 HDEBUG(D_transport) debug_printf("will pipeline QUIT\n");
4083 tctx.options |= topt_no_flush;
4087 #ifndef DISABLE_DKIM
4088 sx->ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
4090 sx->ok = transport_write_message(&tctx, 0);
4093 /* transport_write_message() uses write() because it is called from other
4094 places to write to non-sockets. This means that under some OS (e.g. Solaris)
4095 it can exit with "Broken pipe" as its error. This really means that the
4096 socket got closed at the far end. */
4098 transport_write_timeout = 0; /* for subsequent transports */
4100 /* Failure can either be some kind of I/O disaster (including timeout),
4101 or the failure of a transport filter or the expansion of added headers.
4102 Or, when CHUNKING, it can be a protocol-detected failure. */
4105 if (message) goto SEND_FAILED;
4106 else goto RESPONSE_FAILED;
4108 /* We used to send the terminating "." explicitly here, but because of
4109 buffering effects at both ends of TCP/IP connections, you don't gain
4110 anything by keeping it separate, so it might as well go in the final
4111 data buffer for efficiency. This is now done by setting the topt_end_dot
4114 smtp_command = US"end of data";
4116 /* If we can pipeline a QUIT with the data them send it now. If a new message
4117 for this host appeared in the queue while data was being sent, we will not see
4118 it and it will have to wait for a queue run. If there was one but another
4119 thread took it, we might attempt to send it - but locking of spoolfiles will
4120 detect that. Use _MORE to get QUIT in FIN segment. */
4122 if (tcw_done && !tcw)
4124 /*XXX jgh 2021/03/10 google et. al screwup. G, at least, sends TCP FIN in response to TLS
4125 close-notify. Under TLS 1.3, violating RFC.
4126 However, TLS 1.2 does not have half-close semantics. */
4128 if ( sx->cctx.tls_ctx
4129 #if 0 && !defined(DISABLE_TLS)
4130 && Ustrcmp(tls_out.ver, "TLS1.3") != 0
4132 || !f.deliver_firsttime
4134 { /* Send QUIT now and not later */
4135 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
4136 sx->send_quit = FALSE;
4139 { /* add QUIT to the output buffer */
4140 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4141 sx->send_quit = FALSE; /* avoid sending it later */
4144 if (sx->cctx.tls_ctx && sx->send_tlsclose) /* need to send TLS Close Notify */
4146 # ifdef EXIM_TCP_CORK /* Use _CORK to get Close Notify in FIN segment */
4147 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4149 tls_shutdown_wr(sx->cctx.tls_ctx);
4150 sx->send_tlsclose = FALSE; /* avoid later repeat */
4153 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4154 shutdown(sx->cctx.sock, SHUT_WR); /* flush output buffer, with TCP FIN */
4158 if (smtp_peer_options & OPTION_CHUNKING && sx->cmd_count > 1)
4160 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
4161 switch(sync_responses(sx, sx->cmd_count-1, 0))
4163 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
4164 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
4167 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
4168 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
4169 case 0: break; /* No 2xx or 5xx, but no probs */
4171 case -1: goto END_OFF; /* Timeout on RCPT */
4173 #ifndef DISABLE_PIPE_CONNECT
4174 case -5: /* TLS first-read error */
4175 case -4: HDEBUG(D_transport)
4176 debug_printf("failed reaping pipelined cmd responses\n");
4178 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
4182 #ifndef DISABLE_PRDR
4183 /* For PRDR we optionally get a partial-responses warning followed by the
4184 individual responses, before going on with the overall response. If we don't
4185 get the warning then deal with per non-PRDR. */
4189 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '3', ob->final_timeout);
4190 if (!sx->ok && errno == 0) switch(sx->buffer[0])
4192 case '2': sx->prdr_active = FALSE;
4195 case '4': errno = ERRNO_DATA4XX;
4196 addrlist->more_errno |=
4197 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4204 /* For non-PRDR SMTP, we now read a single response that applies to the
4205 whole message. If it is OK, then all the addresses have been delivered. */
4209 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4211 if (!sx->ok && errno == 0 && sx->buffer[0] == '4')
4213 errno = ERRNO_DATA4XX;
4214 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4218 /* For LMTP, we get back a response for every RCPT command that we sent;
4219 some may be accepted and some rejected. For those that get a response, their
4220 status is fixed; any that are accepted have been handed over, even if later
4221 responses crash - at least, that's how I read RFC 2033.
4223 If all went well, mark the recipient addresses as completed, record which
4224 host/IPaddress they were delivered to, and cut out RSET when sending another
4225 message down the same channel. Write the completed addresses to the journal
4226 now so that they are recorded in case there is a crash of hardware or
4227 software before the spool gets updated. Also record the final SMTP
4228 confirmation if needed (for SMTP only). */
4233 struct timeval delivery_time;
4235 uschar * conf = NULL;
4237 timesince(&delivery_time, &sx->delivery_start);
4238 sx->send_rset = FALSE;
4239 pipelining_active = FALSE;
4241 /* Set up confirmation if needed - applies only to SMTP */
4244 #ifdef DISABLE_EVENT
4245 LOGGING(smtp_confirmation) &&
4250 const uschar * s = string_printing(sx->buffer);
4251 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4252 conf = s == sx->buffer ? US string_copy(s) : US s;
4255 /* Process all transported addresses - for LMTP or PRDR, read a status for
4256 each one. We used to drop out at first_addr, until someone returned a 452
4257 followed by a 250... and we screwed up the accepted addresses. */
4259 for (address_item * addr = addrlist; addr; addr = addr->next)
4261 if (addr->transport_return != PENDING_OK) continue;
4263 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
4264 remaining addresses. Otherwise, it's a return code for just the one
4265 address. For temporary errors, add a retry item for the address so that
4266 it doesn't get tried again too soon. */
4268 #ifndef DISABLE_PRDR
4269 if (sx->lmtp || sx->prdr_active)
4274 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4277 if (errno != 0 || sx->buffer[0] == 0) goto RESPONSE_FAILED;
4278 addr->message = string_sprintf(
4279 #ifndef DISABLE_PRDR
4280 "%s error after %s: %s", sx->prdr_active ? "PRDR":"LMTP",
4282 "LMTP error after %s: %s",
4284 data_command, string_printing(sx->buffer));
4285 setflag(addr, af_pass_message); /* Allow message to go to user */
4286 if (sx->buffer[0] == '5')
4287 addr->transport_return = FAIL;
4290 errno = ERRNO_DATA4XX;
4291 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4292 addr->transport_return = DEFER;
4293 #ifndef DISABLE_PRDR
4294 if (!sx->prdr_active)
4296 retry_add_item(addr, addr->address_retry_key, 0);
4300 sx->completed_addr = TRUE; /* NOW we can set this flag */
4301 if (LOGGING(smtp_confirmation))
4303 const uschar *s = string_printing(sx->buffer);
4304 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4305 conf = (s == sx->buffer) ? US string_copy(s) : US s;
4309 /* SMTP, or success return from LMTP for this address. Pass back the
4310 actual host that was used. */
4312 addr->transport_return = OK;
4313 addr->host_used = host;
4314 addr->delivery_time = delivery_time;
4315 addr->special_action = flag;
4316 addr->message = conf;
4318 if (tcp_out_fastopen)
4320 setflag(addr, af_tcp_fastopen_conn);
4321 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
4322 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
4324 if (sx->pipelining_used) setflag(addr, af_pipelining);
4325 #ifndef DISABLE_PIPE_CONNECT
4326 if (sx->early_pipe_active) setflag(addr, af_early_pipe);
4328 #ifndef DISABLE_PRDR
4329 if (sx->prdr_active) setflag(addr, af_prdr_used);
4331 if (smtp_peer_options & OPTION_CHUNKING) setflag(addr, af_chunking_used);
4334 #ifndef DISABLE_PRDR
4335 if (!sx->prdr_active)
4338 /* Update the journal. For homonymic addresses, use the base address plus
4339 the transport name. See lots of comments in deliver.c about the reasons
4340 for the complications when homonyms are involved. Just carry on after
4341 write error, as it may prove possible to update the spool file later. */
4343 if (testflag(addr, af_homonym))
4344 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4346 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4348 DEBUG(D_deliver) debug_printf("S:journalling %s", sx->buffer);
4349 len = Ustrlen(CS sx->buffer);
4350 if (write(journal_fd, sx->buffer, len) != len)
4351 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4352 "%s: %s", sx->buffer, strerror(errno));
4356 #ifndef DISABLE_PRDR
4357 if (sx->prdr_active)
4359 const uschar * overall_message;
4361 /* PRDR - get the final, overall response. For any non-success
4362 upgrade all the address statuses. */
4364 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4368 if(errno == 0 && sx->buffer[0] == '4')
4370 errno = ERRNO_DATA4XX;
4371 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4373 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4374 if (sx->buffer[0] == '5' || addr->transport_return == OK)
4375 addr->transport_return = PENDING_OK; /* allow set_errno action */
4376 goto RESPONSE_FAILED;
4379 /* Append the overall response to the individual PRDR response for logging
4380 and update the journal, or setup retry. */
4382 overall_message = string_printing(sx->buffer);
4383 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4384 if (addr->transport_return == OK)
4385 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
4387 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4388 if (addr->transport_return == OK)
4390 if (testflag(addr, af_homonym))
4391 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4393 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4395 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx->buffer);
4396 len = Ustrlen(CS sx->buffer);
4397 if (write(journal_fd, sx->buffer, len) != len)
4398 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4399 "%s: %s", sx->buffer, strerror(errno));
4401 else if (addr->transport_return == DEFER)
4402 /*XXX magic value -2 ? maybe host+message ? */
4403 retry_add_item(addr, addr->address_retry_key, -2);
4407 /* Ensure the journal file is pushed out to disk. */
4409 if (EXIMfsync(journal_fd) < 0)
4410 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
4416 /* Handle general (not specific to one address) failures here. The value of ok
4417 is used to skip over this code on the falling through case. A timeout causes a
4418 deferral. Other errors may defer or fail according to the response code, and
4419 may set up a special errno value, e.g. after connection chopped, which is
4420 assumed if errno == 0 and there is no text in the buffer. If control reaches
4421 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
4422 the problem is not related to this specific message. */
4427 uschar * set_message;
4433 /* Clear send_quit flag if needed. Do not set. */
4434 sx->send_quit &= check_response(host, &save_errno, addrlist->more_errno,
4435 sx->buffer, &code, &message, &pass_message);
4443 message = string_sprintf("smtp send to %s [%s] failed: %s",
4444 host->name, host->address, message ? message : US strerror(save_errno));
4445 sx->send_quit = FALSE;
4453 sx->ok = FALSE; /* For when reached by GOTO */
4454 set_message = message;
4456 /* We want to handle timeouts after MAIL or "." and loss of connection after
4457 "." specially. They can indicate a problem with the sender address or with
4458 the contents of the message rather than a real error on the connection. These
4459 cases are treated in the same way as a 4xx response. This next bit of code
4460 does the classification. */
4467 message_error = TRUE;
4471 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4472 Ustrncmp(smtp_command,"end ",4) == 0;
4475 case ERRNO_SMTPCLOSED:
4476 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4479 #ifndef DISABLE_DKIM
4481 /* DKIM signing failure: avoid thinking we pipelined quit,
4482 just abandon the message and close the socket. */
4484 message_error = FALSE;
4485 # ifndef DISABLE_TLS
4486 if (sx->cctx.tls_ctx)
4488 tls_close(sx->cctx.tls_ctx,
4489 sx->send_tlsclose ? TLS_SHUTDOWN_WAIT : TLS_SHUTDOWN_WONLY);
4490 sx->cctx.tls_ctx = NULL;
4496 message_error = FALSE;
4500 /* Handle the cases that are treated as message errors. These are:
4502 (a) negative response or timeout after MAIL
4503 (b) negative response after DATA
4504 (c) negative response or timeout or dropped connection after "."
4505 (d) utf8 support required and not offered
4507 It won't be a negative response or timeout after RCPT, as that is dealt
4508 with separately above. The action in all cases is to set an appropriate
4509 error code for all the addresses, but to leave yield set to OK because the
4510 host itself has not failed. Of course, it might in practice have failed
4511 when we've had a timeout, but if so, we'll discover that at the next
4512 delivery attempt. For a temporary error, set the message_defer flag, and
4513 write to the logs for information if this is not the last host. The error
4514 for the last host will be logged as part of the address's log line. */
4518 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4520 /* If there's an errno, the message contains just the identity of
4525 else /* Anything other than 5 is treated as temporary */
4529 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4531 write_logs(host, message, sx->first_addr ? sx->first_addr->basic_errno : 0);
4533 *message_defer = TRUE;
4536 DEBUG(D_transport) if (sx->cctx.sock >= 0)
4539 if (ioctl(sx->cctx.sock, TIOCOUTQ, &n) == 0)
4540 debug_printf("%d bytes remain in socket output buffer\n", n);
4544 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4545 ".", or some other transportation error. We defer all addresses and yield
4546 DEFER, except for the case of failed add_headers expansion, or a transport
4547 filter failure, when the yield should be ERROR, to stop it trying other
4552 #ifndef DISABLE_PIPE_CONNECT
4553 /* If we were early-pipelinng and the actual EHLO response did not match
4554 the cached value we assumed, we could have detected it and passed a
4555 custom errno through to here. It would be nice to RSET and retry right
4556 away, but to reliably do that we eould need an extra synch point before
4557 we committed to data and that would discard half the gained roundrips.
4558 Or we could summarily drop the TCP connection. but that is also ugly.
4559 Instead, we ignore the possibility (having freshened the cache) and rely
4560 on the server telling us with a nonmessage error if we have tried to
4561 do something it no longer supports. */
4564 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4565 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4569 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host,
4570 #ifdef EXPERIMENTAL_DSN_INFO
4571 sx->smtp_greeting, sx->helo_response,
4573 &sx->delivery_start);
4576 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4577 SMTP session tidily. However, if there were too many addresses to send in one
4578 message (indicated by first_addr being non-NULL) we want to carry on with the
4579 rest of them. Also, it is desirable to send more than one message down the SMTP
4580 connection if there are several waiting, provided we haven't already sent so
4581 many as to hit the configured limit. The function transport_check_waiting looks
4582 for a waiting message and returns its id. Then transport_pass_socket tries to
4583 set up a continued delivery by passing the socket on to another process. The
4584 variable send_rset is FALSE if a message has just been successfully transferred.
4586 If we are already sending down a continued channel, there may be further
4587 addresses not yet delivered that are aimed at the same host, but which have not
4588 been passed in this run of the transport. In this case, continue_more will be
4589 true, and all we should do is send RSET if necessary, and return, leaving the
4592 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4593 do not want to continue with other messages down the same channel, because that
4594 can lead to looping between two or more messages, all with the same,
4595 temporarily failing address(es). [The retry information isn't updated yet, so
4596 new processes keep on trying.] We probably also don't want to try more of this
4597 message's addresses either.
4599 If we have started a TLS session, we have to end it before passing the
4600 connection to a new process. However, not all servers can handle this (Exim
4601 can), so we do not pass such a connection on if the host matches
4602 hosts_nopass_tls. */
4605 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4606 "yield=%d first_address is %sNULL\n", sx->ok, sx->send_quit,
4607 sx->send_rset, f.continue_more, yield, sx->first_addr ? "not " : "");
4609 if (sx->completed_addr && sx->ok && sx->send_quit)
4610 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4611 if (mail_limit = continue_sequence >= sx->max_mail)
4614 debug_printf("reached limit %u for MAILs per conn\n", sx->max_mail);
4619 smtp_compare_t t_compare =
4620 {.tblock = tblock, .current_sender_address = sender_address};
4622 if ( sx->first_addr /* more addrs for this message */
4623 || f.continue_more /* more addrs for continued-host */
4624 || tcw_done && tcw /* more messages for host */
4627 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4628 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4632 transport_check_waiting(tblock->name, host->name,
4633 sx->max_mail, new_message_id,
4634 (oicf)smtp_are_same_identities, (void*)&t_compare)
4641 if (! (sx->ok = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4643 msg = US string_sprintf("smtp send to %s [%s] failed: %s", host->name,
4644 host->address, strerror(errno));
4645 sx->send_quit = FALSE;
4647 else if (! (sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4648 '2', ob->command_timeout)))
4651 sx->send_quit = check_response(host, &errno, 0, sx->buffer, &code, &msg,
4655 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4656 host->name, host->address, msg);
4660 /* Either RSET was not needed, or it succeeded */
4667 int socket_fd = sx->cctx.sock;
4669 if (sx->first_addr) /* More addresses still to be sent */
4670 { /* for this message */
4671 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4672 /* Any that we marked as skipped, reset to do now */
4673 for (address_item * a = sx->first_addr; a; a = a->next)
4674 if (a->transport_return == SKIP)
4675 a->transport_return = PENDING_DEFER;
4677 continue_sequence++; /* for consistency */
4678 clearflag(sx->first_addr, af_new_conn);
4679 setflag(sx->first_addr, af_cont_conn); /* Causes * in logging */
4680 pipelining_active = sx->pipelining_used; /* was cleared at DATA */
4684 /* Unless caller said it already has more messages listed for this host,
4685 pass the connection on to a new Exim process (below, the call to
4686 transport_pass_socket). If the caller has more ready, just return with
4687 the connection still open. */
4690 if (tls_out.active.sock >= 0)
4691 if ( f.continue_more
4692 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4694 /* Before passing the socket on, or returning to caller with it still
4695 open, we must shut down TLS. Not all MTAs allow for the continuation
4696 of the SMTP session when TLS is shut down. We test for this by sending
4697 a new EHLO. If we don't get a good response, we don't attempt to pass
4700 tls_close(sx->cctx.tls_ctx,
4701 sx->send_tlsclose ? TLS_SHUTDOWN_WAIT : TLS_SHUTDOWN_WONLY);
4702 sx->send_tlsclose = FALSE;
4703 sx->cctx.tls_ctx = NULL;
4704 tls_out.active.sock = -1;
4705 smtp_peer_options = smtp_peer_options_wrap;
4707 && smtp_write_command(sx, SCMD_FLUSH, "EHLO %s\r\n", sx->helo_data)
4709 && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4710 '2', ob->command_timeout);
4712 if (sx->ok && f.continue_more)
4713 goto TIDYUP; /* More addresses for another run */
4717 /* Set up a pipe for proxying TLS for the new transport process */
4719 smtp_peer_options |= OPTION_TLS;
4720 if ((sx->ok = socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4723 set_errno(sx->first_addr, errno, US"internal allocation problem",
4725 # ifdef EXPERIMENTAL_DSN_INFO
4726 sx->smtp_greeting, sx->helo_response,
4728 &sx->delivery_start);
4732 if (f.continue_more)
4733 goto TIDYUP; /* More addresses for another run */
4735 /* If the socket is successfully passed, we mustn't send QUIT (or
4736 indeed anything!) from here. */
4738 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4739 propagate it from the initial
4741 if (sx->ok && transport_pass_socket(tblock->name, host->name,
4742 host->address, new_message_id, socket_fd
4743 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4744 , sx->peer_limit_mail, sx->peer_limit_rcpt, sx->peer_limit_rcptdom
4748 sx->send_quit = FALSE;
4750 /* We have passed the client socket to a fresh transport process.
4751 If TLS is still active, we need to proxy it for the transport we
4752 just passed the baton to. Fork a child to to do it, and return to
4753 get logging done asap. Which way to place the work makes assumptions
4754 about post-fork prioritisation which may not hold on all platforms. */
4756 if (tls_out.active.sock >= 0)
4758 int pid = exim_fork(US"tls-proxy-interproc");
4759 if (pid == 0) /* child; fork again to disconnect totally */
4761 /* does not return */
4762 smtp_proxy_tls(sx->cctx.tls_ctx, sx->buffer, sizeof(sx->buffer), pfd,
4763 ob->command_timeout, host->name);
4766 if (pid > 0) /* parent */
4769 /* tidy the inter-proc to disconn the proxy proc */
4770 waitpid(pid, NULL, 0);
4771 tls_close(sx->cctx.tls_ctx, TLS_NO_SHUTDOWN);
4772 sx->cctx.tls_ctx = NULL;
4773 (void)close(sx->cctx.sock);
4775 continue_transport = NULL;
4776 continue_hostname = NULL;
4779 log_write(0, LOG_PANIC_DIE, "fork failed");
4785 /* If RSET failed and there are addresses left, they get deferred. */
4787 set_errno(sx->first_addr, errno, msg, DEFER, FALSE, host,
4788 #ifdef EXPERIMENTAL_DSN_INFO
4789 sx->smtp_greeting, sx->helo_response,
4791 &sx->delivery_start);
4795 /* End off tidily with QUIT unless the connection has died or the socket has
4796 been passed to another process. */
4800 { /* Use _MORE to get QUIT in FIN segment */
4801 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4803 if (sx->cctx.tls_ctx && sx->send_tlsclose)
4805 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
4806 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4808 tls_shutdown_wr(sx->cctx.tls_ctx);
4809 sx->send_tlsclose = FALSE;
4816 /* Close the socket, and return the appropriate value, first setting
4817 works because the NULL setting is passed back to the calling process, and
4818 remote_max_parallel is forced to 1 when delivering over an existing connection,
4820 If all went well and continue_more is set, we shouldn't actually get here if
4821 there are further addresses, as the return above will be taken. However,
4822 writing RSET might have failed, or there may be other addresses whose hosts are
4823 specified in the transports, and therefore not visible at top level, in which
4824 case continue_more won't get set. */
4828 /* This flushes data queued in the socket, being the QUIT and any TLS Close,
4829 sending them along with the client FIN flag. Us (we hope) sending FIN first
4830 means we (client) take the TIME_WAIT state, so the server (which likely has a
4831 higher connection rate) does not have to. */
4833 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4834 shutdown(sx->cctx.sock, SHUT_WR);
4837 if (sx->send_quit || tcw_done && !tcw)
4839 /* Wait for (we hope) ack of our QUIT, and a server FIN. Discard any data
4840 received, then discard the socket. Any packet received after then, or receive
4841 data still in the socket, will get a RST - hence the pause/drain. */
4843 /* Reap the response to QUIT, timing out after one second */
4844 (void) smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', 1);
4846 if (sx->cctx.tls_ctx)
4850 /* Reap the TLS Close Notify from the server, timing out after one second */
4851 sigalrm_seen = FALSE;
4854 n = tls_read(sx->cctx.tls_ctx, sx->inbuffer, sizeof(sx->inbuffer));
4855 while (!sigalrm_seen && n > 0);
4858 if (sx->send_tlsclose)
4860 # ifdef EXIM_TCP_CORK
4861 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4863 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4866 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WONLY);
4867 sx->cctx.tls_ctx = NULL;
4871 /* Drain any trailing data from the socket before close, to avoid sending a RST */
4873 if ( poll_one_fd(sx->cctx.sock, POLLIN, 20) != 0 /* 20ms */
4874 && fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4875 for (int i = 16, n; /* drain socket */
4876 (n = read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer))) > 0 && i > 0;
4877 i--) HDEBUG(D_transport|D_acl|D_v)
4880 debug_printf_indent(" SMTP(drain %d bytes)<< %.*s\n", n, m, sx->inbuffer);
4881 for (m = 0; m < n; m++)
4882 debug_printf("0x%02x\n", sx->inbuffer[m]);
4885 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4886 (void)close(sx->cctx.sock);
4888 continue_transport = NULL;
4889 continue_hostname = NULL;
4890 smtp_debug_cmd_report();
4892 #ifndef DISABLE_EVENT
4893 (void) event_raise(tblock->event_action, US"tcp:close", NULL, NULL);
4899 sx->first_addr = NULL;
4900 for (address_item * a = sx->addrlist->next; a; a = a->next)
4901 if (a->transport_return == DANE)
4903 a->transport_return = PENDING_DEFER;
4904 if (!sx->first_addr)
4906 /* Remember the new start-point in the addrlist, for smtp_setup_conn()
4907 to get the domain string for SNI */
4910 clearflag(a, af_cont_conn);
4911 setflag(a, af_new_conn); /* clear * from logging */
4912 DEBUG(D_transport) debug_printf("DANE: go-around for %s\n", a->domain);
4915 continue_sequence = 1; /* for consistency */
4920 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4921 if (mail_limit && sx->first_addr)
4923 /* Reset the sequence count since we closed the connection. This is flagged
4924 on the pipe back to the delivery process so that a non-continued-conn delivery
4927 continue_sequence = 1; /* for consistency */
4928 clearflag(sx->first_addr, af_cont_conn);
4929 setflag(sx->first_addr, af_new_conn); /* clear * from logging */
4938 if (dane_held) for (address_item * a = sx->addrlist->next; a; a = a->next)
4939 if (a->transport_return == DANE)
4940 a->transport_return = PENDING_DEFER;
4948 /*************************************************
4949 * Closedown entry point *
4950 *************************************************/
4952 /* This function is called when exim is passed an open smtp channel
4953 from another incarnation, but the message which it has been asked
4954 to deliver no longer exists. The channel is on stdin.
4956 We might do fancy things like looking for another message to send down
4957 the channel, but if the one we sought has gone, it has probably been
4958 delivered by some other process that itself will seek further messages,
4959 so just close down our connection.
4961 Argument: pointer to the transport instance block
4966 smtp_transport_closedown(transport_instance *tblock)
4968 smtp_transport_options_block * ob = SOB tblock->options_block;
4969 client_conn_ctx cctx;
4972 uschar inbuffer[4096];
4973 uschar outbuffer[16];
4975 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4976 cctx.sock = fileno(stdin);
4977 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4979 sx.inblock.cctx = &cctx;
4980 sx.inblock.buffer = inbuffer;
4981 sx.inblock.buffersize = sizeof(inbuffer);
4982 sx.inblock.ptr = inbuffer;
4983 sx.inblock.ptrend = inbuffer;
4985 sx.outblock.cctx = &cctx;
4986 sx.outblock.buffersize = sizeof(outbuffer);
4987 sx.outblock.buffer = outbuffer;
4988 sx.outblock.ptr = outbuffer;
4989 sx.outblock.cmd_count = 0;
4990 sx.outblock.authenticating = FALSE;
4992 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4993 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
4994 (void)close(cctx.sock);
4999 /*************************************************
5000 * Prepare addresses for delivery *
5001 *************************************************/
5003 /* This function is called to flush out error settings from previous delivery
5004 attempts to other hosts. It also records whether we got here via an MX record
5005 or not in the more_errno field of the address. We are interested only in
5006 addresses that are still marked DEFER - others may have got delivered to a
5007 previously considered IP address. Set their status to PENDING_DEFER to indicate
5008 which ones are relevant this time.
5011 addrlist the list of addresses
5012 host the host we are delivering to
5014 Returns: the first address for this delivery
5017 static address_item *
5018 prepare_addresses(address_item *addrlist, host_item *host)
5020 address_item *first_addr = NULL;
5021 for (address_item * addr = addrlist; addr; addr = addr->next)
5022 if (addr->transport_return == DEFER)
5024 if (!first_addr) first_addr = addr;
5025 addr->transport_return = PENDING_DEFER;
5026 addr->basic_errno = 0;
5027 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
5028 addr->message = NULL;
5030 addr->cipher = NULL;
5031 addr->ourcert = NULL;
5032 addr->peercert = NULL;
5033 addr->peerdn = NULL;
5034 addr->ocsp = OCSP_NOT_REQ;
5035 addr->tlsver = NULL;
5037 #ifdef EXPERIMENTAL_DSN_INFO
5038 addr->smtp_greeting = NULL;
5039 addr->helo_response = NULL;
5047 /*************************************************
5048 * Main entry point *
5049 *************************************************/
5051 /* See local README for interface details. As this is a remote transport, it is
5052 given a chain of addresses to be delivered in one connection, if possible. It
5053 always returns TRUE, indicating that each address has its own independent
5054 status set, except if there is a setting up problem, in which case it returns
5058 smtp_transport_entry(
5059 transport_instance *tblock, /* data for this instantiation */
5060 address_item *addrlist) /* addresses we are working on */
5063 int hosts_defer = 0;
5065 int hosts_looked_up = 0;
5066 int hosts_retry = 0;
5067 int hosts_serial = 0;
5068 int hosts_total = 0;
5069 int total_hosts_tried = 0;
5070 BOOL expired = TRUE;
5071 uschar *expanded_hosts = NULL;
5073 uschar *tid = string_sprintf("%s transport", tblock->name);
5074 smtp_transport_options_block *ob = SOB tblock->options_block;
5075 host_item *hostlist = addrlist->host_list;
5076 host_item *host = NULL;
5080 debug_printf("%s transport entered\n", tblock->name);
5081 for (address_item * addr = addrlist; addr; addr = addr->next)
5082 debug_printf(" %s\n", addr->address);
5085 debug_printf("hostlist:\n");
5086 for (host_item * host = hostlist; host; host = host->next)
5087 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
5089 if (continue_hostname)
5090 debug_printf("already connected to %s [%s] (on fd %d)\n",
5091 continue_hostname, continue_host_address,
5092 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
5095 /* Check the restrictions on line length */
5097 if (max_received_linelength > ob->message_linelength_limit)
5100 gettimeofday(&now, NULL);
5102 for (address_item * addr = addrlist; addr; addr = addr->next)
5103 if (addr->transport_return == DEFER)
5104 addr->transport_return = PENDING_DEFER;
5106 set_errno_nohost(addrlist, ERRNO_SMTPFORMAT,
5107 US"message has lines too long for transport", FAIL, TRUE, &now);
5111 /* Set the flag requesting that these hosts be added to the waiting
5112 database if the delivery fails temporarily or if we are running with
5113 queue_smtp or a 2-stage queue run. This gets unset for certain
5114 kinds of error, typically those that are specific to the message. */
5116 update_waiting = TRUE;
5118 /* If a host list is not defined for the addresses - they must all have the
5119 same one in order to be passed to a single transport - or if the transport has
5120 a host list with hosts_override set, use the host list supplied with the
5121 transport. It is an error for this not to exist. */
5123 if (!hostlist || (ob->hosts_override && ob->hosts))
5127 addrlist->message = string_sprintf("%s transport called with no hosts set",
5129 addrlist->transport_return = PANIC;
5130 return FALSE; /* Only top address has status */
5133 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
5136 /* If the transport's host list contains no '$' characters, and we are not
5137 randomizing, it is fixed and therefore a chain of hosts can be built once
5138 and for all, and remembered for subsequent use by other calls to this
5139 transport. If, on the other hand, the host list does contain '$', or we are
5140 randomizing its order, we have to rebuild it each time. In the fixed case,
5141 as the hosts string will never be used again, it doesn't matter that we
5142 replace all the : characters with zeros. */
5146 uschar *s = ob->hosts;
5148 if (Ustrchr(s, '$'))
5150 if (!(expanded_hosts = expand_string(s)))
5152 addrlist->message = string_sprintf("failed to expand list of hosts "
5153 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
5154 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
5155 return FALSE; /* Only top address has status */
5157 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
5158 "\"%s\"\n", s, expanded_hosts);
5162 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
5166 log_write(0, LOG_MAIN|LOG_PANIC,
5167 "attempt to use tainted host list '%s' from '%s' in transport %s",
5168 s, ob->hosts, tblock->name);
5169 /* Avoid leaking info to an attacker */
5170 addrlist->message = US"internal configuration error";
5171 addrlist->transport_return = PANIC;
5175 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
5177 /* Check that the expansion yielded something useful. */
5181 string_sprintf("%s transport has empty hosts setting", tblock->name);
5182 addrlist->transport_return = PANIC;
5183 return FALSE; /* Only top address has status */
5186 /* If there was no expansion of hosts, save the host list for
5189 if (!expanded_hosts) ob->hostlist = hostlist;
5192 /* This is not the first time this transport has been run in this delivery;
5193 the host list was built previously. */
5196 hostlist = ob->hostlist;
5199 /* The host list was supplied with the address. If hosts_randomize is set, we
5200 must sort it into a random order if it did not come from MX records and has not
5201 already been randomized (but don't bother if continuing down an existing
5204 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
5206 host_item *newlist = NULL;
5209 host_item *h = hostlist;
5210 hostlist = hostlist->next;
5212 h->sort_key = random_number(100);
5219 else if (h->sort_key < newlist->sort_key)
5226 host_item *hh = newlist;
5229 if (h->sort_key < hh->next->sort_key) break;
5237 hostlist = addrlist->host_list = newlist;
5240 /* Sort out the default port. */
5242 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
5244 /* For each host-plus-IP-address on the list:
5246 . If this is a continued delivery and the host isn't the one with the
5247 current connection, skip.
5249 . If the status is unusable (i.e. previously failed or retry checked), skip.
5251 . If no IP address set, get the address, either by turning the name into
5252 an address, calling gethostbyname if gethostbyname is on, or by calling
5253 the DNS. The DNS may yield multiple addresses, in which case insert the
5254 extra ones into the list.
5256 . Get the retry data if not previously obtained for this address and set the
5257 field which remembers the state of this address. Skip if the retry time is
5258 not reached. If not, remember whether retry data was found. The retry string
5259 contains both the name and the IP address.
5261 . Scan the list of addresses and mark those whose status is DEFER as
5262 PENDING_DEFER. These are the only ones that will be processed in this cycle
5265 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
5266 Some addresses may be successfully delivered, others may fail, and yet
5267 others may get temporary errors and so get marked DEFER.
5269 . The return from the delivery attempt is OK if a connection was made and a
5270 valid SMTP dialogue was completed. Otherwise it is DEFER.
5272 . If OK, add a "remove" retry item for this host/IPaddress, if any.
5274 . If fail to connect, or other defer state, add a retry item.
5276 . If there are any addresses whose status is still DEFER, carry on to the
5277 next host/IPaddress, unless we have tried the number of hosts given
5278 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
5279 there is some fancy logic for hosts_max_try that means its limit can be
5280 overstepped in some circumstances.
5282 If we get to the end of the list, all hosts have deferred at least one address,
5283 or not reached their retry times. If delay_after_cutoff is unset, it requests a
5284 delivery attempt to those hosts whose last try was before the arrival time of
5285 the current message. To cope with this, we have to go round the loop a second
5286 time. After that, set the status and error data for any addresses that haven't
5287 had it set already. */
5289 for (int cutoff_retry = 0;
5290 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
5293 host_item *nexthost = NULL;
5294 int unexpired_hosts_tried = 0;
5295 BOOL continue_host_tried = FALSE;
5297 retry_non_continued:
5298 for (host = hostlist;
5300 && unexpired_hosts_tried < ob->hosts_max_try
5301 && total_hosts_tried < ob->hosts_max_try_hardlimit;
5306 BOOL host_is_expired = FALSE;
5307 BOOL message_defer = FALSE;
5308 BOOL some_deferred = FALSE;
5309 address_item *first_addr = NULL;
5310 uschar *interface = NULL;
5311 uschar *retry_host_key = NULL;
5312 uschar *retry_message_key = NULL;
5313 uschar *serialize_key = NULL;
5315 /* Deal slightly better with a possible Linux kernel bug that results
5316 in intermittent TFO-conn fails deep into the TCP flow. Bug 2907 tracks.
5317 Hack: Clear TFO option for any further hosts on this tpt run. */
5319 if (total_hosts_tried > 0)
5321 DEBUG(D_transport|D_acl|D_v)
5322 debug_printf("Clearing TFO as not first host for message\n");
5323 ob->hosts_try_fastopen = US"";
5326 /* Default next host is next host. :-) But this can vary if the
5327 hosts_max_try limit is hit (see below). It may also be reset if a host
5328 address is looked up here (in case the host was multihomed). */
5330 nexthost = host->next;
5332 /* If the address hasn't yet been obtained from the host name, look it up
5333 now, unless the host is already marked as unusable. If it is marked as
5334 unusable, it means that the router was unable to find its IP address (in
5335 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
5336 the lookup failed last time. We don't get this far if *all* MX records
5337 point to non-existent hosts; that is treated as a hard error.
5339 We can just skip this host entirely. When the hosts came from the router,
5340 the address will timeout based on the other host(s); when the address is
5341 looked up below, there is an explicit retry record added.
5343 Note that we mustn't skip unusable hosts if the address is not unset; they
5344 may be needed as expired hosts on the 2nd time round the cutoff loop. */
5348 int new_port, flags;
5350 if (host->status >= hstatus_unusable)
5352 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
5357 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
5359 /* The host name is permitted to have an attached port. Find it, and
5360 strip it from the name. Just remember it for now. */
5362 new_port = host_item_get_port(host);
5364 /* Count hosts looked up */
5368 /* Find by name if so configured, or if it's an IP address. We don't
5369 just copy the IP address, because we need the test-for-local to happen. */
5371 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
5372 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
5373 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
5375 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
5376 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
5378 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
5379 &ob->dnssec, /* domains for request/require */
5382 /* Update the host (and any additional blocks, resulting from
5383 multihoming) with a host-specific port, if any. */
5385 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
5387 /* Failure to find the host at this time (usually DNS temporary failure)
5388 is really a kind of routing failure rather than a transport failure.
5389 Therefore we add a retry item of the routing kind, not to stop us trying
5390 to look this name up here again, but to ensure the address gets timed
5391 out if the failures go on long enough. A complete failure at this point
5392 commonly points to a configuration error, but the best action is still
5393 to carry on for the next host. */
5395 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
5397 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
5399 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
5400 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
5401 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
5402 host->status = hstatus_unusable;
5404 for (address_item * addr = addrlist; addr; addr = addr->next)
5406 if (addr->transport_return != DEFER) continue;
5407 addr->basic_errno = ERRNO_UNKNOWNHOST;
5408 addr->message = string_sprintf(
5409 rc == HOST_FIND_SECURITY
5410 ? "lookup of IP address for %s was insecure"
5411 : "failed to lookup IP address for %s",
5417 /* If the host is actually the local host, we may have a problem, or
5418 there may be some cunning configuration going on. In the problem case,
5419 log things and give up. The default transport status is already DEFER. */
5421 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
5423 for (address_item * addr = addrlist; addr; addr = addr->next)
5425 addr->basic_errno = ERRNO_HOST_IS_LOCAL;
5426 addr->message = string_sprintf("%s transport found host %s to be "
5427 "local", tblock->name, host->name);
5431 } /* End of block for IP address lookup */
5433 /* If this is a continued delivery, we are interested only in the host
5434 which matches the name of the existing open channel. The check is put
5435 here after the local host lookup, in case the name gets expanded as a
5436 result of the lookup. Set expired FALSE, to save the outer loop executing
5439 if (continue_hostname)
5440 if ( Ustrcmp(continue_hostname, host->name) != 0
5441 || Ustrcmp(continue_host_address, host->address) != 0
5445 continue; /* With next host */
5448 continue_host_tried = TRUE;
5450 /* Reset the default next host in case a multihomed host whose addresses
5451 are not looked up till just above added to the host list. */
5453 nexthost = host->next;
5455 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
5456 domain is in queue_smtp_domains, we don't actually want to attempt any
5457 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
5458 there is a lookup defer in queue_smtp_domains, proceed as if the domain
5459 were not in it. We don't want to hold up all SMTP deliveries! Except when
5460 doing a two-stage queue run, don't do this if forcing. */
5462 if ( (!f.deliver_force || f.queue_2stage)
5464 || match_isinlist(addrlist->domain,
5465 CUSS &queue_smtp_domains, 0,
5466 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK)
5469 DEBUG(D_transport) debug_printf("first-pass routing only\n");
5471 for (address_item * addr = addrlist; addr; addr = addr->next)
5472 if (addr->transport_return == DEFER)
5473 addr->message = US"first-pass only routing due to -odqs, "
5474 "queue_smtp_domains or control=queue";
5475 continue; /* With next host */
5478 /* Count hosts being considered - purely for an intelligent comment
5479 if none are usable. */
5483 /* Set $host and $host address now in case they are needed for the
5484 interface expansion or the serialize_hosts check; they remain set if an
5485 actual delivery happens. */
5487 deliver_host = host->name;
5488 deliver_host_address = host->address;
5489 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
5490 : host->dnssec == DS_NO ? US"no"
5493 /* Set up a string for adding to the retry key if the port number is not
5494 the standard SMTP port. A host may have its own port setting that overrides
5497 pistring = string_sprintf(":%d", host->port == PORT_NONE
5498 ? defport : host->port);
5499 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
5501 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
5502 string is set, even if constant (as different transports can have different
5503 constant settings), we must add it to the key that is used for retries,
5504 because connections to the same host from a different interface should be
5505 treated separately. */
5507 host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
5509 uschar * s = ob->interface;
5512 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
5514 pistring = string_sprintf("%s/%s", pistring, interface);
5518 /* The first time round the outer loop, check the status of the host by
5519 inspecting the retry data. The second time round, we are interested only
5520 in expired hosts that haven't been tried since this message arrived. */
5522 if (cutoff_retry == 0)
5525 /* Ensure the status of the address is set by checking retry data if
5526 necessary. There may be host-specific retry data (applicable to all
5527 messages) and also data for retries of a specific message at this host.
5528 If either of these retry records are actually read, the keys used are
5529 returned to save recomputing them later. */
5531 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5532 US"retry_include_ip_address", ob->retry_include_ip_address,
5533 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5534 continue; /* with next host */
5536 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
5537 incl_ip, &retry_host_key, &retry_message_key);
5539 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
5540 host->address ? host->address : US"", pistring,
5541 host->status == hstatus_usable ? "usable"
5542 : host->status == hstatus_unusable ? "unusable"
5543 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
5545 /* Skip this address if not usable at this time, noting if it wasn't
5546 actually expired, both locally and in the address. */
5548 switch (host->status)
5550 case hstatus_unusable:
5552 setflag(addrlist, af_retry_skipped);
5555 case hstatus_unusable_expired:
5558 case hwhy_retry: hosts_retry++; break;
5559 case hwhy_failed: hosts_fail++; break;
5561 case hwhy_deferred: hosts_defer++; break;
5564 /* If there was a retry message key, implying that previously there
5565 was a message-specific defer, we don't want to update the list of
5566 messages waiting for these hosts. */
5568 if (retry_message_key) update_waiting = FALSE;
5569 continue; /* With the next host or IP address */
5573 /* Second time round the loop: if the address is set but expired, and
5574 the message is newer than the last try, let it through. */
5579 || host->status != hstatus_unusable_expired
5580 || host->last_try > received_time.tv_sec)
5582 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
5583 host->name, host->address, pistring);
5584 host_is_expired = TRUE;
5587 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
5588 it remains TRUE only if all hosts are expired and none are actually tried.
5593 /* If this host is listed as one to which access must be serialized,
5594 see if another Exim process has a connection to it, and if so, skip
5595 this host. If not, update the database to record our connection to it
5596 and remember this for later deletion. Do not do any of this if we are
5597 sending the message down a pre-existing connection. */
5599 if ( !continue_hostname
5600 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
5602 serialize_key = string_sprintf("host-serialize-%s", host->name);
5603 if (!enq_start(serialize_key, 1))
5606 debug_printf("skipping host %s because another Exim process "
5607 "is connected to it\n", host->name);
5613 /* OK, we have an IP address that is not waiting for its retry time to
5614 arrive (it might be expired) OR (second time round the loop) we have an
5615 expired host that hasn't been tried since the message arrived. Have a go
5616 at delivering the message to it. First prepare the addresses by flushing
5617 out the result of previous attempts, and finding the first address that
5618 is still to be delivered. */
5620 first_addr = prepare_addresses(addrlist, host);
5622 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5623 message_id, host->name, host->address, addrlist->address,
5624 addrlist->next ? ", ..." : "");
5626 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5627 message_id, host->name, host->address, pistring, addrlist->address,
5628 addrlist->next ? ", ..." : "");
5630 /* This is not for real; don't do the delivery. If there are
5631 any remaining hosts, list them. */
5636 gettimeofday(&now, NULL);
5637 set_errno_nohost(addrlist, 0, NULL, OK, FALSE, &now);
5638 for (address_item * addr = addrlist; addr; addr = addr->next)
5640 addr->host_used = host;
5641 addr->special_action = '*';
5642 addr->message = US"delivery bypassed by -N option";
5646 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5647 "*** host and remaining hosts:\n", tblock->name);
5648 for (host_item * host2 = host; host2; host2 = host2->next)
5649 debug_printf(" %s [%s]\n", host2->name,
5650 host2->address ? host2->address : US"unset");
5655 /* This is for real. If the host is expired, we don't count it for
5656 hosts_max_retry. This ensures that all hosts must expire before an address
5657 is timed out, unless hosts_max_try_hardlimit (which protects against
5658 lunatic DNS configurations) is reached.
5660 If the host is not expired and we are about to hit the hosts_max_retry
5661 limit, check to see if there is a subsequent hosts with a different MX
5662 value. If so, make that the next host, and don't count this one. This is a
5663 heuristic to make sure that different MXs do get tried. With a normal kind
5664 of retry rule, they would get tried anyway when the earlier hosts were
5665 delayed, but if the domain has a "retry every time" type of rule - as is
5666 often used for the the very large ISPs, that won't happen. */
5671 /* Make a copy of the host if it is local to this invocation
5672 of the transport. */
5676 thost = store_get(sizeof(host_item), GET_UNTAINTED);
5678 thost->name = string_copy(host->name);
5679 thost->address = string_copy(host->address);
5684 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5687 debug_printf("hosts_max_try limit reached with this host\n");
5688 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5691 unexpired_hosts_tried--;
5692 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5693 "and will be tried\n");
5698 /* Attempt the delivery. */
5700 total_hosts_tried++;
5701 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5702 &message_defer, FALSE);
5705 OK => connection made, each address contains its result;
5706 message_defer is set for message-specific defers (when all
5707 recipients are marked defer)
5708 DEFER => there was a non-message-specific delivery problem;
5709 ERROR => there was a problem setting up the arguments for a filter,
5710 or there was a problem with expanding added headers
5713 /* If the result is not OK, there was a non-message-specific problem.
5714 If the result is DEFER, we need to write to the logs saying what happened
5715 for this particular host, except in the case of authentication and TLS
5716 failures, where the log has already been written. If all hosts defer a
5717 general message is written at the end. */
5719 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5720 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5721 write_logs(host, first_addr->message, first_addr->basic_errno);
5723 #ifndef DISABLE_EVENT
5725 deferred_event_raise(first_addr, host, US"msg:host:defer");
5728 /* If STARTTLS was accepted, but there was a failure in setting up the
5729 TLS session (usually a certificate screwup), and the host is not in
5730 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5731 TLS forcibly turned off. We have to start from scratch with a new SMTP
5732 connection. That's why the retry is done from here, not from within
5733 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5734 session, so the in-clear transmission after those errors, if permitted,
5735 happens inside smtp_deliver().] */
5739 && first_addr->basic_errno == ERRNO_TLSFAILURE
5740 && ob->tls_tempfail_tryclear
5741 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5744 log_write(0, LOG_MAIN,
5745 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5746 first_addr->message, host->name, host->address);
5747 first_addr = prepare_addresses(addrlist, host);
5748 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5749 &message_defer, TRUE);
5750 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5751 write_logs(host, first_addr->message, first_addr->basic_errno);
5752 # ifndef DISABLE_EVENT
5754 deferred_event_raise(first_addr, host, US"msg:host:defer");
5757 #endif /*DISABLE_TLS*/
5759 #ifndef DISABLE_EVENT
5760 /* If the last host gave a defer raise a per-message event */
5763 && unexpired_hosts_tried < ob->hosts_max_try
5764 && total_hosts_tried < ob->hosts_max_try_hardlimit
5766 && (message_defer || rc == DEFER)
5768 deferred_event_raise(first_addr, host, US"msg:defer");
5772 /* Delivery attempt finished */
5774 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5775 message_id, host->name, host->address, pistring, addrlist->address,
5776 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5778 /* Release serialization if set up */
5780 if (serialize_key) enq_end(serialize_key);
5782 /* If the result is DEFER, or if a host retry record is known to exist, we
5783 need to add an item to the retry chain for updating the retry database
5784 at the end of delivery. We only need to add the item to the top address,
5785 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5786 for any other delivery attempts using the same address. (It is copied into
5787 the unusable tree at the outer level, so even if different address blocks
5788 contain the same address, it still won't get tried again.) */
5790 if (rc == DEFER || retry_host_key)
5792 int delete_flag = rc != DEFER ? rf_delete : 0;
5793 if (!retry_host_key)
5796 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5797 US"retry_include_ip_address", ob->retry_include_ip_address,
5798 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5799 incl_ip = TRUE; /* error; use most-specific retry record */
5801 retry_host_key = incl_ip
5802 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5803 : string_sprintf("T:%S%s", host->name, pistring);
5806 /* If a delivery of another message over an existing SMTP connection
5807 yields DEFER, we do NOT set up retry data for the host. This covers the
5808 case when there are delays in routing the addresses in the second message
5809 that are so long that the server times out. This is alleviated by not
5810 routing addresses that previously had routing defers when handling an
5811 existing connection, but even so, this case may occur (e.g. if a
5812 previously happily routed address starts giving routing defers). If the
5813 host is genuinely down, another non-continued message delivery will
5814 notice it soon enough. */
5816 if (delete_flag != 0 || !continue_hostname)
5817 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5819 /* We may have tried an expired host, if its retry time has come; ensure
5820 the status reflects the expiry for the benefit of any other addresses. */
5824 host->status = host_is_expired
5825 ? hstatus_unusable_expired : hstatus_unusable;
5826 host->why = hwhy_deferred;
5830 /* If message_defer is set (host was OK, but every recipient got deferred
5831 because of some message-specific problem), or if that had happened
5832 previously so that a message retry key exists, add an appropriate item
5833 to the retry chain. Note that if there was a message defer but now there is
5834 a host defer, the message defer record gets deleted. That seems perfectly
5835 reasonable. Also, stop the message from being remembered as waiting
5836 for specific hosts. */
5838 if (message_defer || retry_message_key)
5840 int delete_flag = message_defer ? 0 : rf_delete;
5841 if (!retry_message_key)
5844 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5845 US"retry_include_ip_address", ob->retry_include_ip_address,
5846 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5847 incl_ip = TRUE; /* error; use most-specific retry record */
5849 retry_message_key = incl_ip
5850 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5852 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5854 retry_add_item(addrlist, retry_message_key,
5855 rf_message | rf_host | delete_flag);
5856 update_waiting = FALSE;
5859 /* Any return other than DEFER (that is, OK or ERROR) means that the
5860 addresses have got their final statuses filled in for this host. In the OK
5861 case, see if any of them are deferred. */
5864 for (address_item * addr = addrlist; addr; addr = addr->next)
5865 if (addr->transport_return == DEFER)
5867 some_deferred = TRUE;
5871 /* If no addresses deferred or the result was ERROR, return. We do this for
5872 ERROR because a failing filter set-up or add_headers expansion is likely to
5873 fail for any host we try. */
5875 if (rc == ERROR || (rc == OK && !some_deferred))
5877 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5878 return TRUE; /* Each address has its status */
5881 /* If the result was DEFER or some individual addresses deferred, let
5882 the loop run to try other hosts with the deferred addresses, except for the
5883 case when we were trying to deliver down an existing channel and failed.
5884 Don't try any other hosts in this case. */
5886 if (continue_hostname) break;
5888 /* If the whole delivery, or some individual addresses, were deferred and
5889 there are more hosts that could be tried, do not count this host towards
5890 the hosts_max_try limit if the age of the message is greater than the
5891 maximum retry time for this host. This means we may try try all hosts,
5892 ignoring the limit, when messages have been around for some time. This is
5893 important because if we don't try all hosts, the address will never time
5894 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5896 if ((rc == DEFER || some_deferred) && nexthost)
5899 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5901 if (retry && retry->rules)
5903 retry_rule *last_rule;
5904 for (last_rule = retry->rules;
5906 last_rule = last_rule->next);
5907 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5909 else timedout = TRUE; /* No rule => timed out */
5913 unexpired_hosts_tried--;
5914 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5915 "hosts_max_try (message older than host's retry time)\n");
5921 if (unexpired_hosts_tried >= ob->hosts_max_try)
5922 debug_printf("reached transport hosts_max_try limit %d\n",
5924 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5925 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5926 ob->hosts_max_try_hardlimit);
5929 testharness_pause_ms(500); /* let server debug out */
5930 } /* End of loop for trying multiple hosts. */
5932 /* If we failed to find a matching host in the list, for an already-open
5933 connection, just close it and start over with the list. This can happen
5934 for routing that changes from run to run, or big multi-IP sites with
5937 if (continue_hostname && !continue_host_tried)
5939 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5941 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5943 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5945 /*XXX doublecheck that! */
5947 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5949 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5950 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5951 cutthrough.cctx.tls_ctx = NULL;
5952 cutthrough.is_tls = FALSE;
5956 (void) write(fd, US"QUIT\r\n", 6);
5959 cutthrough.cctx.sock = -1;
5960 continue_hostname = NULL;
5961 goto retry_non_continued;
5964 /* This is the end of the loop that repeats iff expired is TRUE and
5965 ob->delay_after_cutoff is FALSE. The second time round we will
5966 try those hosts that haven't been tried since the message arrived. */
5970 debug_printf("all IP addresses skipped or deferred at least one address\n");
5971 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5972 debug_printf("retrying IP addresses not tried since message arrived\n");
5977 /* Get here if all IP addresses are skipped or defer at least one address. In
5978 MUA wrapper mode, this will happen only for connection or other non-message-
5979 specific failures. Force the delivery status for all addresses to FAIL. */
5983 for (address_item * addr = addrlist; addr; addr = addr->next)
5984 addr->transport_return = FAIL;
5988 /* In the normal, non-wrapper case, add a standard message to each deferred
5989 address if there hasn't been an error, that is, if it hasn't actually been
5990 tried this time. The variable "expired" will be FALSE if any deliveries were
5991 actually tried, or if there was at least one host that was not expired. That
5992 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
5993 a delivery has been tried, an error code will be set, and the failing of the
5994 message is handled by the retry code later.
5996 If queue_smtp is set, or this transport was called to send a subsequent message
5997 down an existing TCP/IP connection, and something caused the host not to be
5998 found, we end up here, but can detect these cases and handle them specially. */
6000 for (address_item * addr = addrlist; addr; addr = addr->next)
6002 /* If host is not NULL, it means that we stopped processing the host list
6003 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
6004 means we need to behave as if some hosts were skipped because their retry
6005 time had not come. Specifically, this prevents the address from timing out.
6006 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
6007 hosts were tried. */
6010 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
6013 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
6014 "hosts were tried\n");
6019 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
6020 setflag(addr, af_retry_skipped);
6023 if (f.queue_smtp) /* no deliveries attempted */
6025 addr->transport_return = DEFER;
6026 addr->basic_errno = 0;
6027 addr->message = US"SMTP delivery explicitly queued";
6030 else if ( addr->transport_return == DEFER
6031 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
6035 addr->basic_errno = ERRNO_HRETRY;
6036 if (continue_hostname)
6037 addr->message = US"no host found for existing SMTP connection";
6040 setflag(addr, af_pass_message); /* This is not a security risk */
6041 addr->message = string_sprintf(
6042 "all hosts%s have been failing for a long time %s",
6043 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
6044 ob->delay_after_cutoff
6045 ? US"(and retry time not reached)"
6046 : US"and were last tried after this message arrived");
6048 /* If we are already using fallback hosts, or there are no fallback hosts
6049 defined, convert the result to FAIL to cause a bounce. */
6051 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
6052 addr->transport_return = FAIL;
6057 if (hosts_retry == hosts_total)
6058 s = "retry time not reached for any host%s";
6059 else if (hosts_fail == hosts_total)
6060 s = "all host address lookups%s failed permanently";
6061 else if (hosts_defer == hosts_total)
6062 s = "all host address lookups%s failed temporarily";
6063 else if (hosts_serial == hosts_total)
6064 s = "connection limit reached for all hosts%s";
6065 else if (hosts_fail+hosts_defer == hosts_total)
6066 s = "all host address lookups%s failed";
6068 s = "some host address lookups failed and retry time "
6069 "not reached for other hosts or connection limit reached%s";
6071 addr->message = string_sprintf(s,
6072 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
6077 /* Update the database which keeps information about which messages are waiting
6078 for which hosts to become available. For some message-specific errors, the
6079 update_waiting flag is turned off because we don't want follow-on deliveries in
6080 those cases. If this transport instance is explicitly limited to one message
6081 per connection then follow-on deliveries are not possible and there's no need
6082 to create/update the per-transport wait-<transport_name> database. */
6084 if (update_waiting && tblock->connection_max_messages != 1)
6085 transport_update_waiting(hostlist, tblock->name);
6089 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
6091 return TRUE; /* Each address has its status */
6094 #endif /*!MACRO_PREDEF*/
6097 /* End of transport/smtp.c */