1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* Copyright (c) The Exim Maintainers 2020 */
7 /* See the file NOTICE for conditions of use and distribution. */
12 #if defined(SUPPORT_DANE) && defined(DISABLE_TLS)
13 # error TLS is required for DANE
17 /* Options specific to the smtp transport. This transport also supports LMTP
18 over TCP/IP. The options must be in alphabetic order (note that "_" comes
19 before the lower case letters). Some live in the transport_instance block so as
20 to be publicly visible; these are flagged with opt_public. */
22 #define LOFF(field) OPT_OFF(smtp_transport_options_block, field)
24 optionlist smtp_transport_options[] = {
25 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
26 OPT_OFF(transport_instance, expand_multi_domain) },
27 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
28 LOFF(expand_retry_include_ip_address) },
30 { "address_retry_include_sender", opt_bool,
31 LOFF(address_retry_include_sender) },
32 { "allow_localhost", opt_bool, LOFF(allow_localhost) },
33 #ifdef EXPERIMENTAL_ARC
34 { "arc_sign", opt_stringptr, LOFF(arc_sign) },
36 { "authenticated_sender", opt_stringptr, LOFF(authenticated_sender) },
37 { "authenticated_sender_force", opt_bool, LOFF(authenticated_sender_force) },
38 { "command_timeout", opt_time, LOFF(command_timeout) },
39 { "connect_timeout", opt_time, LOFF(connect_timeout) },
40 { "connection_max_messages", opt_int | opt_public,
41 OPT_OFF(transport_instance, connection_max_messages) },
43 { "dane_require_tls_ciphers", opt_stringptr, LOFF(dane_require_tls_ciphers) },
45 { "data_timeout", opt_time, LOFF(data_timeout) },
46 { "delay_after_cutoff", opt_bool, LOFF(delay_after_cutoff) },
48 { "dkim_canon", opt_stringptr, LOFF(dkim.dkim_canon) },
49 { "dkim_domain", opt_stringptr, LOFF(dkim.dkim_domain) },
50 { "dkim_hash", opt_stringptr, LOFF(dkim.dkim_hash) },
51 { "dkim_identity", opt_stringptr, LOFF(dkim.dkim_identity) },
52 { "dkim_private_key", opt_stringptr, LOFF(dkim.dkim_private_key) },
53 { "dkim_selector", opt_stringptr, LOFF(dkim.dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr, LOFF(dkim.dkim_sign_headers) },
55 { "dkim_strict", opt_stringptr, LOFF(dkim.dkim_strict) },
56 { "dkim_timestamps", opt_stringptr, LOFF(dkim.dkim_timestamps) },
58 { "dns_qualify_single", opt_bool, LOFF(dns_qualify_single) },
59 { "dns_search_parents", opt_bool, LOFF(dns_search_parents) },
60 { "dnssec_request_domains", opt_stringptr, LOFF(dnssec.request) },
61 { "dnssec_require_domains", opt_stringptr, LOFF(dnssec.require) },
62 { "dscp", opt_stringptr, LOFF(dscp) },
63 { "fallback_hosts", opt_stringptr, LOFF(fallback_hosts) },
64 { "final_timeout", opt_time, LOFF(final_timeout) },
65 { "gethostbyname", opt_bool, LOFF(gethostbyname) },
66 { "helo_data", opt_stringptr, LOFF(helo_data) },
67 { "hosts", opt_stringptr, LOFF(hosts) },
68 { "hosts_avoid_esmtp", opt_stringptr, LOFF(hosts_avoid_esmtp) },
69 { "hosts_avoid_pipelining", opt_stringptr, LOFF(hosts_avoid_pipelining) },
71 { "hosts_avoid_tls", opt_stringptr, LOFF(hosts_avoid_tls) },
73 { "hosts_max_try", opt_int, LOFF(hosts_max_try) },
74 { "hosts_max_try_hardlimit", opt_int, LOFF(hosts_max_try_hardlimit) },
76 { "hosts_nopass_tls", opt_stringptr, LOFF(hosts_nopass_tls) },
77 { "hosts_noproxy_tls", opt_stringptr, LOFF(hosts_noproxy_tls) },
79 { "hosts_override", opt_bool, LOFF(hosts_override) },
80 #ifndef DISABLE_PIPE_CONNECT
81 { "hosts_pipe_connect", opt_stringptr, LOFF(hosts_pipe_connect) },
83 { "hosts_randomize", opt_bool, LOFF(hosts_randomize) },
84 #if !defined(DISABLE_TLS) && !defined(DISABLE_OCSP)
85 { "hosts_request_ocsp", opt_stringptr, LOFF(hosts_request_ocsp) },
87 { "hosts_require_auth", opt_stringptr, LOFF(hosts_require_auth) },
90 { "hosts_require_dane", opt_stringptr, LOFF(hosts_require_dane) },
93 { "hosts_require_ocsp", opt_stringptr, LOFF(hosts_require_ocsp) },
95 { "hosts_require_tls", opt_stringptr, LOFF(hosts_require_tls) },
97 { "hosts_try_auth", opt_stringptr, LOFF(hosts_try_auth) },
98 { "hosts_try_chunking", opt_stringptr, LOFF(hosts_try_chunking) },
100 { "hosts_try_dane", opt_stringptr, LOFF(hosts_try_dane) },
102 { "hosts_try_fastopen", opt_stringptr, LOFF(hosts_try_fastopen) },
104 { "hosts_try_prdr", opt_stringptr, LOFF(hosts_try_prdr) },
107 { "hosts_verify_avoid_tls", opt_stringptr, LOFF(hosts_verify_avoid_tls) },
109 { "interface", opt_stringptr, LOFF(interface) },
110 { "keepalive", opt_bool, LOFF(keepalive) },
111 { "lmtp_ignore_quota", opt_bool, LOFF(lmtp_ignore_quota) },
112 { "max_rcpt", opt_int | opt_public,
113 OPT_OFF(transport_instance, max_addresses) },
114 { "message_linelength_limit", opt_int, LOFF(message_linelength_limit) },
115 { "multi_domain", opt_expand_bool | opt_public,
116 OPT_OFF(transport_instance, multi_domain) },
117 { "port", opt_stringptr, LOFF(port) },
118 { "protocol", opt_stringptr, LOFF(protocol) },
119 { "retry_include_ip_address", opt_expand_bool, LOFF(retry_include_ip_address) },
120 { "serialize_hosts", opt_stringptr, LOFF(serialize_hosts) },
121 { "size_addition", opt_int, LOFF(size_addition) },
123 { "socks_proxy", opt_stringptr, LOFF(socks_proxy) },
126 { "tls_certificate", opt_stringptr, LOFF(tls_certificate) },
127 { "tls_crl", opt_stringptr, LOFF(tls_crl) },
128 { "tls_dh_min_bits", opt_int, LOFF(tls_dh_min_bits) },
129 { "tls_privatekey", opt_stringptr, LOFF(tls_privatekey) },
130 { "tls_require_ciphers", opt_stringptr, LOFF(tls_require_ciphers) },
131 # ifndef DISABLE_TLS_RESUME
132 { "tls_resumption_hosts", opt_stringptr, LOFF(tls_resumption_hosts) },
134 { "tls_sni", opt_stringptr, LOFF(tls_sni) },
135 { "tls_tempfail_tryclear", opt_bool, LOFF(tls_tempfail_tryclear) },
136 { "tls_try_verify_hosts", opt_stringptr, LOFF(tls_try_verify_hosts) },
137 { "tls_verify_cert_hostnames", opt_stringptr, LOFF(tls_verify_cert_hostnames)},
138 { "tls_verify_certificates", opt_stringptr, LOFF(tls_verify_certificates) },
139 { "tls_verify_hosts", opt_stringptr, LOFF(tls_verify_hosts) },
142 { "utf8_downconvert", opt_stringptr, LOFF(utf8_downconvert) },
146 /* Size of the options list. An extern variable has to be used so that its
147 address can appear in the tables drtables.c. */
149 int smtp_transport_options_count = nelem(smtp_transport_options);
155 smtp_transport_options_block smtp_transport_option_defaults = {0};
156 void smtp_transport_init(transport_instance *tblock) {}
157 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
158 void smtp_transport_closedown(transport_instance *tblock) {}
160 #else /*!MACRO_PREDEF*/
163 /* Default private options block for the smtp transport. */
165 smtp_transport_options_block smtp_transport_option_defaults = {
166 /* All non-mentioned elements 0/NULL/FALSE */
167 .helo_data = US"$primary_hostname",
168 .protocol = US"smtp",
169 .hosts_try_chunking = US"*",
171 .hosts_try_dane = US"*",
173 .hosts_try_fastopen = US"*",
175 .hosts_try_prdr = US"*",
178 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
180 .command_timeout = 5*60,
181 .connect_timeout = 5*60,
182 .data_timeout = 5*60,
183 .final_timeout = 10*60,
184 .size_addition = 1024,
186 .hosts_max_try_hardlimit = 50,
187 .message_linelength_limit = 998,
188 .address_retry_include_sender = TRUE,
189 .dns_qualify_single = TRUE,
190 .dnssec = { .request= US"*", .require=NULL },
191 .delay_after_cutoff = TRUE,
193 .retry_include_ip_address = TRUE,
195 # if defined(SUPPORT_SYSDEFAULT_CABUNDLE) || !defined(USE_GNUTLS)
196 .tls_verify_certificates = US"system",
198 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
199 .tls_tempfail_tryclear = TRUE,
200 .tls_try_verify_hosts = US"*",
201 .tls_verify_cert_hostnames = US"*",
204 .utf8_downconvert = US"-1",
208 { .dkim_hash = US"sha256", },
212 /* some DSN flags for use later */
214 static int rf_list[] = {rf_notify_never, rf_notify_success,
215 rf_notify_failure, rf_notify_delay };
217 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
223 static uschar *smtp_command; /* Points to last cmd for error messages */
224 static uschar *mail_command; /* Points to MAIL cmd for error messages */
225 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
226 static BOOL update_waiting; /* TRUE to update the "wait" database */
228 /*XXX move to smtp_context */
229 static BOOL pipelining_active; /* current transaction is in pipe mode */
232 static unsigned ehlo_response(uschar * buf, unsigned checks);
235 /******************************************************************************/
238 smtp_deliver_init(void)
240 if (!regex_PIPELINING) regex_PIPELINING =
241 regex_must_compile(US"\\n250[\\s\\-]PIPELINING(\\s|\\n|$)", FALSE, TRUE);
243 if (!regex_SIZE) regex_SIZE =
244 regex_must_compile(US"\\n250[\\s\\-]SIZE(\\s|\\n|$)", FALSE, TRUE);
246 if (!regex_AUTH) regex_AUTH =
247 regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
250 if (!regex_STARTTLS) regex_STARTTLS =
251 regex_must_compile(US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE, TRUE);
254 if (!regex_CHUNKING) regex_CHUNKING =
255 regex_must_compile(US"\\n250[\\s\\-]CHUNKING(\\s|\\n|$)", FALSE, TRUE);
258 if (!regex_PRDR) regex_PRDR =
259 regex_must_compile(US"\\n250[\\s\\-]PRDR(\\s|\\n|$)", FALSE, TRUE);
263 if (!regex_UTF8) regex_UTF8 =
264 regex_must_compile(US"\\n250[\\s\\-]SMTPUTF8(\\s|\\n|$)", FALSE, TRUE);
267 if (!regex_DSN) regex_DSN =
268 regex_must_compile(US"\\n250[\\s\\-]DSN(\\s|\\n|$)", FALSE, TRUE);
270 if (!regex_IGNOREQUOTA) regex_IGNOREQUOTA =
271 regex_must_compile(US"\\n250[\\s\\-]IGNOREQUOTA(\\s|\\n|$)", FALSE, TRUE);
273 #ifndef DISABLE_PIPE_CONNECT
274 if (!regex_EARLY_PIPE) regex_EARLY_PIPE =
275 regex_must_compile(US"\\n250[\\s\\-]" EARLY_PIPE_FEATURE_NAME "(\\s|\\n|$)", FALSE, TRUE);
280 /*************************************************
281 * Setup entry point *
282 *************************************************/
284 /* This function is called when the transport is about to be used,
285 but before running it in a sub-process. It is used for two things:
287 (1) To set the fallback host list in addresses, when delivering.
288 (2) To pass back the interface, port, protocol, and other options, for use
289 during callout verification.
292 tblock pointer to the transport instance block
293 addrlist list of addresses about to be transported
294 tf if not NULL, pointer to block in which to return options
295 uid the uid that will be set (not used)
296 gid the gid that will be set (not used)
297 errmsg place for error message (not used)
299 Returns: OK always (FAIL, DEFER not used)
303 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
304 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
306 smtp_transport_options_block *ob = SOB tblock->options_block;
308 /* Pass back options if required. This interface is getting very messy. */
312 tf->interface = ob->interface;
314 tf->protocol = ob->protocol;
315 tf->hosts = ob->hosts;
316 tf->hosts_override = ob->hosts_override;
317 tf->hosts_randomize = ob->hosts_randomize;
318 tf->gethostbyname = ob->gethostbyname;
319 tf->qualify_single = ob->dns_qualify_single;
320 tf->search_parents = ob->dns_search_parents;
321 tf->helo_data = ob->helo_data;
324 /* Set the fallback host list for all the addresses that don't have fallback
325 host lists, provided that the local host wasn't present in the original host
328 if (!testflag(addrlist, af_local_host_removed))
329 for (; addrlist; addrlist = addrlist->next)
330 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
337 /*************************************************
338 * Initialization entry point *
339 *************************************************/
341 /* Called for each instance, after its options have been read, to
342 enable consistency checks to be done, or anything else that needs
345 Argument: pointer to the transport instance block
350 smtp_transport_init(transport_instance *tblock)
352 smtp_transport_options_block *ob = SOB tblock->options_block;
354 /* Retry_use_local_part defaults FALSE if unset */
356 if (tblock->retry_use_local_part == TRUE_UNSET)
357 tblock->retry_use_local_part = FALSE;
359 /* Set the default port according to the protocol */
362 ob->port = strcmpic(ob->protocol, US"lmtp") == 0
364 : strcmpic(ob->protocol, US"smtps") == 0
365 ? US"smtps" : US"smtp";
367 /* Set up the setup entry point, to be called before subprocesses for this
370 tblock->setup = smtp_transport_setup;
372 /* Complain if any of the timeouts are zero. */
374 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
375 ob->final_timeout <= 0)
376 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
377 "command, data, or final timeout value is zero for %s transport",
380 /* If hosts_override is set and there are local hosts, set the global
381 flag that stops verify from showing router hosts. */
383 if (ob->hosts_override && ob->hosts) tblock->overrides_hosts = TRUE;
385 /* If there are any fallback hosts listed, build a chain of host items
386 for them, but do not do any lookups at this time. */
388 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
395 /*************************************************
396 * Set delivery info into all active addresses *
397 *************************************************/
399 /* Only addresses whose status is >= PENDING are relevant. A lesser
400 status means that an address is not currently being processed.
403 addrlist points to a chain of addresses
404 errno_value to put in each address's errno field
405 msg to put in each address's message field
406 rc to put in each address's transport_return field
407 pass_message if TRUE, set the "pass message" flag in the address
408 host if set, mark addrs as having used this host
409 smtp_greeting from peer
410 helo_response from peer
411 start points to timestamp of delivery start
413 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
414 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
415 this particular type of timeout.
421 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
422 BOOL pass_message, host_item * host,
423 #ifdef EXPERIMENTAL_DSN_INFO
424 const uschar * smtp_greeting, const uschar * helo_response,
426 struct timeval * start
430 struct timeval deliver_time;
432 if (errno_value == ERRNO_CONNECTTIMEOUT)
434 errno_value = ETIMEDOUT;
435 orvalue = RTEF_CTOUT;
437 timesince(&deliver_time, start);
439 for (address_item * addr = addrlist; addr; addr = addr->next)
440 if (addr->transport_return >= PENDING)
442 addr->basic_errno = errno_value;
443 addr->more_errno |= orvalue;
444 addr->delivery_time = deliver_time;
448 if (pass_message) setflag(addr, af_pass_message);
450 addr->transport_return = rc;
453 addr->host_used = host;
454 #ifdef EXPERIMENTAL_DSN_INFO
456 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
457 addr->smtp_greeting = smtp_greeting;
460 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
461 addr->helo_response = helo_response;
468 set_errno_nohost(address_item * addrlist, int errno_value, uschar * msg, int rc,
469 BOOL pass_message, struct timeval * start)
471 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL,
472 #ifdef EXPERIMENTAL_DSN_INFO
479 /*************************************************
480 * Check an SMTP response *
481 *************************************************/
483 /* This function is given an errno code and the SMTP response buffer
484 to analyse, together with the host identification for generating messages. It
485 sets an appropriate message and puts the first digit of the response code into
486 the yield variable. If no response was actually read, a suitable digit is
490 host the current host, to get its name for messages
491 errno_value pointer to the errno value
492 more_errno from the top address for use with ERRNO_FILTER_FAIL
493 buffer the SMTP response buffer
494 yield where to put a one-digit SMTP response code
495 message where to put an error message
496 pass_message set TRUE if message is an SMTP response
498 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
502 check_response(host_item *host, int *errno_value, int more_errno,
503 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
505 uschar * pl = pipelining_active ? US"pipelined " : US"";
508 *yield = '4'; /* Default setting is to give a temporary error */
512 case ETIMEDOUT: /* Handle response timeout */
513 *message = US string_sprintf("SMTP timeout after %s%s",
515 if (transport_count > 0)
516 *message = US string_sprintf("%s (%d bytes written)", *message,
520 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
521 s = string_printing(buffer);
522 while (isspace(*s)) s++;
524 ? string_sprintf("Malformed SMTP reply (an empty line) "
525 "in response to %s%s", pl, smtp_command)
526 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
527 pl, smtp_command, s);
530 case ERRNO_TLSFAILURE: /* Handle bad first read; can happen with
532 *message = US"bad first read from TLS conn";
535 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
536 can't send QUIT as we mustn't end the DATA. */
537 *message = string_sprintf("transport filter process failed (%d)%s",
539 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
542 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
543 can't send QUIT as we mustn't end the DATA. */
545 string_sprintf("failed to expand headers_add or headers_remove: %s",
546 expand_string_message);
549 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
550 *message = US"failed to write a data block";
554 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
555 *message = US"utf8 support required but not offered for forwarding";
556 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
561 /* Handle error responses from the remote mailer. */
565 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
566 "%s", pl, smtp_command, s = string_printing(buffer));
567 *pass_message = TRUE;
572 /* No data was read. If there is no errno, this must be the EOF (i.e.
573 connection closed) case, which causes deferral. An explicit connection reset
574 error has the same effect. Otherwise, put the host's identity in the message,
575 leaving the errno value to be interpreted as well. In all cases, we have to
576 assume the connection is now dead. */
578 if (*errno_value == 0 || *errno_value == ECONNRESET)
580 *errno_value = ERRNO_SMTPCLOSED;
581 *message = US string_sprintf("Remote host closed connection "
582 "in response to %s%s", pl, smtp_command);
585 *message = US string_sprintf("%s [%s]", host->name, host->address);
592 /*************************************************
593 * Write error message to logs *
594 *************************************************/
596 /* This writes to the main log and to the message log.
599 host the current host
600 detail the current message (addr_item->message)
601 basic_errno the errno (addr_item->basic_errno)
607 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
609 gstring * message = LOGGING(outgoing_port)
610 ? string_fmt_append(NULL, "H=%s [%s]:%d", host->name, host->address,
611 host->port == PORT_NONE ? 25 : host->port)
612 : string_fmt_append(NULL, "H=%s [%s]", host->name, host->address);
616 message = string_fmt_append(message, ": %s", suffix);
618 message = string_fmt_append(message, ": %s", strerror(basic_errno));
621 message = string_fmt_append(message, " %s", exim_errstr(basic_errno));
623 log_write(0, LOG_MAIN, "%s", string_from_gstring(message));
624 deliver_msglog("%s %s\n", tod_stamp(tod_log), message->s);
628 msglog_line(host_item * host, uschar * message)
630 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
631 host->name, host->address, message);
636 #ifndef DISABLE_EVENT
637 /*************************************************
638 * Post-defer action *
639 *************************************************/
641 /* This expands an arbitrary per-transport string.
642 It might, for example, be used to write to the database log.
645 addr the address item containing error information
646 host the current host
653 deferred_event_raise(address_item * addr, host_item * host, uschar * evstr)
655 uschar * action = addr->transport->event_action;
656 const uschar * save_domain;
662 save_domain = deliver_domain;
663 save_local = deliver_localpart;
665 /*XXX would ip & port already be set up? */
666 deliver_host_address = string_copy(host->address);
667 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
668 event_defer_errno = addr->basic_errno;
670 router_name = addr->router->name;
671 transport_name = addr->transport->name;
672 deliver_domain = addr->domain;
673 deliver_localpart = addr->local_part;
675 (void) event_raise(action, evstr,
677 ? addr->basic_errno > 0
678 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
679 : string_copy(addr->message)
680 : addr->basic_errno > 0
681 ? string_copy(US strerror(addr->basic_errno))
684 deliver_localpart = save_local;
685 deliver_domain = save_domain;
686 router_name = transport_name = NULL;
690 /*************************************************
691 * Reap SMTP specific responses *
692 *************************************************/
694 smtp_discard_responses(smtp_context * sx, smtp_transport_options_block * ob,
697 uschar flushbuffer[4096];
701 if (!smtp_read_response(sx, flushbuffer, sizeof(flushbuffer),
702 '2', ob->command_timeout)
703 && (errno != 0 || flushbuffer[0] == 0))
710 /* Return boolean success */
713 smtp_reap_banner(smtp_context * sx)
716 #if defined(__linux__) && defined(TCP_QUICKACK)
717 { /* Hack to get QUICKACK disabled; has to be right after 3whs, and has to on->off */
718 int sock = sx->cctx.sock;
719 struct pollfd p = {.fd = sock, .events = POLLOUT};
720 int rc = poll(&p, 1, 1000);
721 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &on, sizeof(on));
722 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
725 good_response = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
726 '2', (SOB sx->conn_args.ob)->command_timeout);
727 #ifdef EXPERIMENTAL_DSN_INFO
728 sx->smtp_greeting = string_copy(sx->buffer);
730 return good_response;
734 smtp_reap_ehlo(smtp_context * sx)
736 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
737 (SOB sx->conn_args.ob)->command_timeout))
739 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
741 #ifdef EXPERIMENTAL_DSN_INFO
742 sx->helo_response = string_copy(sx->buffer);
748 #ifdef EXPERIMENTAL_DSN_INFO
749 sx->helo_response = string_copy(sx->buffer);
751 #ifndef DISABLE_EVENT
752 (void) event_raise(sx->conn_args.tblock->event_action,
753 US"smtp:ehlo", sx->buffer);
760 #ifndef DISABLE_PIPE_CONNECT
762 ehlo_cache_key(const smtp_context * sx)
764 host_item * host = sx->conn_args.host;
765 return Ustrchr(host->address, ':')
766 ? string_sprintf("[%s]:%d.EHLO", host->address,
767 host->port == PORT_NONE ? sx->port : host->port)
768 : string_sprintf("%s:%d.EHLO", host->address,
769 host->port == PORT_NONE ? sx->port : host->port);
773 write_ehlo_cache_entry(const smtp_context * sx)
775 open_db dbblock, * dbm_file;
777 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
779 uschar * ehlo_resp_key = ehlo_cache_key(sx);
780 dbdata_ehlo_resp er = { .data = sx->ehlo_resp };
782 HDEBUG(D_transport) debug_printf("writing clr %04x/%04x cry %04x/%04x\n",
783 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
784 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths);
786 dbfn_write(dbm_file, ehlo_resp_key, &er, (int)sizeof(er));
787 dbfn_close(dbm_file);
792 invalidate_ehlo_cache_entry(smtp_context * sx)
794 open_db dbblock, * dbm_file;
796 if ( sx->early_pipe_active
797 && (dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
799 uschar * ehlo_resp_key = ehlo_cache_key(sx);
800 dbfn_delete(dbm_file, ehlo_resp_key);
801 dbfn_close(dbm_file);
806 read_ehlo_cache_entry(smtp_context * sx)
811 if (!(dbm_file = dbfn_open(US"misc", O_RDONLY, &dbblock, FALSE, TRUE)))
812 { DEBUG(D_transport) debug_printf("ehlo-cache: no misc DB\n"); }
815 uschar * ehlo_resp_key = ehlo_cache_key(sx);
816 dbdata_ehlo_resp * er;
818 if (!(er = dbfn_read_enforce_length(dbm_file, ehlo_resp_key, sizeof(dbdata_ehlo_resp))))
819 { DEBUG(D_transport) debug_printf("no ehlo-resp record\n"); }
820 else if (time(NULL) - er->time_stamp > retry_data_expire)
822 DEBUG(D_transport) debug_printf("ehlo-resp record too old\n");
823 dbfn_close(dbm_file);
824 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
825 dbfn_delete(dbm_file, ehlo_resp_key);
829 sx->ehlo_resp = er->data;
830 dbfn_close(dbm_file);
831 DEBUG(D_transport) debug_printf(
832 "EHLO response bits from cache: cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x\n",
833 er->data.cleartext_features, er->data.cleartext_auths,
834 er->data.crypted_features, er->data.crypted_auths);
837 dbfn_close(dbm_file);
844 /* Return an auths bitmap for the set of AUTH methods offered by the server
845 which match our authenticators. */
847 static unsigned short
848 study_ehlo_auths(smtp_context * sx)
853 unsigned short authbits = 0;
855 if (!sx->esmtp) return 0;
856 if (!regex_AUTH) regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
857 if (!regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)) return 0;
858 expand_nmax = -1; /* reset */
859 names = string_copyn(expand_nstring[1], expand_nlength[1]);
861 for (au = auths, authnum = 0; au; au = au->next, authnum++) if (au->client)
863 const uschar * list = names;
865 for (int sep = ' '; s = string_nextinlist(&list, &sep, NULL, 0); )
866 if (strcmpic(au->public_name, s) == 0)
867 { authbits |= BIT(authnum); break; }
871 debug_printf("server offers %s AUTH, methods '%s', bitmap 0x%04x\n",
872 tls_out.active.sock >= 0 ? "crypted" : "plaintext", names, authbits);
874 if (tls_out.active.sock >= 0)
875 sx->ehlo_resp.crypted_auths = authbits;
877 sx->ehlo_resp.cleartext_auths = authbits;
884 /* Wait for and check responses for early-pipelining.
886 Called from the lower-level smtp_read_response() function
887 used for general code that assume synchronisation, if context
888 flags indicate outstanding early-pipelining commands. Also
889 called fom sync_responses() which handles pipelined commands.
892 sx smtp connection context
893 countp number of outstanding responses, adjusted on return
897 DEFER error on first read of TLS'd conn
898 FAIL SMTP error in response
901 smtp_reap_early_pipe(smtp_context * sx, int * countp)
903 BOOL pending_BANNER = sx->pending_BANNER;
904 BOOL pending_EHLO = sx->pending_EHLO;
907 sx->pending_BANNER = FALSE; /* clear early to avoid recursion */
908 sx->pending_EHLO = FALSE;
912 DEBUG(D_transport) debug_printf("%s expect banner\n", __FUNCTION__);
914 if (!smtp_reap_banner(sx))
916 DEBUG(D_transport) debug_printf("bad banner\n");
917 if (tls_out.active.sock >= 0) rc = DEFER;
924 unsigned peer_offered;
925 unsigned short authbits = 0, * ap;
927 DEBUG(D_transport) debug_printf("%s expect ehlo\n", __FUNCTION__);
929 if (!smtp_reap_ehlo(sx))
931 DEBUG(D_transport) debug_printf("bad response for EHLO\n");
932 if (tls_out.active.sock >= 0) rc = DEFER;
936 /* Compare the actual EHLO response to the cached value we assumed;
937 on difference, dump or rewrite the cache and arrange for a retry. */
939 ap = tls_out.active.sock < 0
940 ? &sx->ehlo_resp.cleartext_auths : &sx->ehlo_resp.crypted_auths;
942 peer_offered = ehlo_response(sx->buffer,
943 (tls_out.active.sock < 0 ? OPTION_TLS : 0)
944 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
945 | OPTION_UTF8 | OPTION_EARLY_PIPE
947 if ( peer_offered != sx->peer_offered
948 || (authbits = study_ehlo_auths(sx)) != *ap)
951 debug_printf("EHLO %s extensions changed, 0x%04x/0x%04x -> 0x%04x/0x%04x\n",
952 tls_out.active.sock < 0 ? "cleartext" : "crypted",
953 sx->peer_offered, *ap, peer_offered, authbits);
954 *(tls_out.active.sock < 0
955 ? &sx->ehlo_resp.cleartext_features : &sx->ehlo_resp.crypted_features) = peer_offered;
957 if (peer_offered & OPTION_EARLY_PIPE)
958 write_ehlo_cache_entry(sx);
960 invalidate_ehlo_cache_entry(sx);
962 return OK; /* just carry on */
968 invalidate_ehlo_cache_entry(sx);
969 (void) smtp_discard_responses(sx, sx->conn_args.ob, *countp);
972 #endif /*!DISABLE_PIPE_CONNECT*/
975 /*************************************************
976 * Synchronize SMTP responses *
977 *************************************************/
979 /* This function is called from smtp_deliver() to receive SMTP responses from
980 the server, and match them up with the commands to which they relate. When
981 PIPELINING is not in use, this function is called after every command, and is
982 therefore somewhat over-engineered, but it is simpler to use a single scheme
983 that works both with and without PIPELINING instead of having two separate sets
986 The set of commands that are buffered up with pipelining may start with MAIL
987 and may end with DATA; in between are RCPT commands that correspond to the
988 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
989 etc.) are never buffered.
991 Errors after MAIL or DATA abort the whole process leaving the response in the
992 buffer. After MAIL, pending responses are flushed, and the original command is
993 re-instated in big_buffer for error messages. For RCPT commands, the remote is
994 permitted to reject some recipient addresses while accepting others. However
995 certain errors clearly abort the whole process. Set the value in
996 transport_return to PENDING_OK if the address is accepted. If there is a
997 subsequent general error, it will get reset accordingly. If not, it will get
998 converted to OK at the end.
1001 sx smtp connection context
1002 count the number of responses to read
1003 pending_DATA 0 if last command sent was not DATA
1004 +1 if previously had a good recipient
1005 -1 if not previously had a good recipient
1007 Returns: 3 if at least one address had 2xx and one had 5xx
1008 2 if at least one address had 5xx but none had 2xx
1009 1 if at least one host had a 2xx response, but none had 5xx
1010 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
1011 -1 timeout while reading RCPT response
1012 -2 I/O or other non-response error for RCPT
1013 -3 DATA or MAIL failed - errno and buffer set
1014 -4 banner or EHLO failed (early-pipelining)
1015 -5 banner or EHLO failed (early-pipelining, TLS)
1019 sync_responses(smtp_context * sx, int count, int pending_DATA)
1021 address_item * addr = sx->sync_addr;
1022 smtp_transport_options_block * ob = sx->conn_args.ob;
1025 #ifndef DISABLE_PIPE_CONNECT
1027 if ((rc = smtp_reap_early_pipe(sx, &count)) != OK)
1028 return rc == FAIL ? -4 : -5;
1031 /* Handle the response for a MAIL command. On error, reinstate the original
1032 command in big_buffer for error message use, and flush any further pending
1033 responses before returning, except after I/O errors and timeouts. */
1035 if (sx->pending_MAIL)
1037 DEBUG(D_transport) debug_printf("%s expect mail\n", __FUNCTION__);
1039 sx->pending_MAIL = sx->RCPT_452 = FALSE;
1040 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1041 '2', ob->command_timeout))
1043 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
1044 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
1045 if (errno == ERRNO_TLSFAILURE)
1047 if (errno == 0 && sx->buffer[0] != 0)
1050 if (sx->buffer[0] == '4')
1052 save_errno = ERRNO_MAIL4XX;
1053 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1055 count = smtp_discard_responses(sx, ob, count);
1059 if (pending_DATA) count--; /* Number of RCPT responses to come */
1060 while (count-- > 0) /* Mark any pending addrs with the host used */
1062 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
1063 addr->host_used = sx->conn_args.host;
1070 if (pending_DATA) count--; /* Number of RCPT responses to come */
1072 /* Read and handle the required number of RCPT responses, matching each one up
1073 with an address by scanning for the next address whose status is PENDING_DEFER.
1078 while (addr->transport_return != PENDING_DEFER)
1079 if (!(addr = addr->next))
1082 /* The address was accepted */
1083 addr->host_used = sx->conn_args.host;
1085 DEBUG(D_transport) debug_printf("%s expect rcpt for %s\n", __FUNCTION__, addr->address);
1086 if (smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1087 '2', ob->command_timeout))
1090 addr->transport_return = PENDING_OK;
1092 /* If af_dr_retry_exists is set, there was a routing delay on this address;
1093 ensure that any address-specific retry record is expunged. We do this both
1094 for the basic key and for the version that also includes the sender. */
1096 if (testflag(addr, af_dr_retry_exists))
1098 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
1100 retry_add_item(addr, altkey, rf_delete);
1101 retry_add_item(addr, addr->address_retry_key, rf_delete);
1105 /* Error on first TLS read */
1107 else if (errno == ERRNO_TLSFAILURE)
1110 /* Timeout while reading the response */
1112 else if (errno == ETIMEDOUT)
1114 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
1115 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1116 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE, &sx->delivery_start);
1117 retry_add_item(addr, addr->address_retry_key, 0);
1118 update_waiting = FALSE;
1122 /* Handle other errors in obtaining an SMTP response by returning -1. This
1123 will cause all the addresses to be deferred. Restore the SMTP command in
1124 big_buffer for which we are checking the response, so the error message
1127 else if (errno != 0 || sx->buffer[0] == 0)
1129 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer }, * g = &gs;
1131 /* Use taint-unchecked routines for writing into big_buffer, trusting
1132 that we'll never expand it. */
1134 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, "RCPT TO:<%s>",
1135 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1136 string_from_gstring(g);
1140 /* Handle SMTP permanent and temporary response codes. */
1145 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
1146 "%s", transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes),
1147 string_printing(sx->buffer));
1148 setflag(addr, af_pass_message);
1150 msglog_line(sx->conn_args.host, addr->message);
1152 /* The response was 5xx */
1154 if (sx->buffer[0] == '5')
1156 addr->transport_return = FAIL;
1160 /* The response was 4xx */
1164 addr->transport_return = DEFER;
1165 addr->basic_errno = ERRNO_RCPT4XX;
1166 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1170 #ifndef DISABLE_EVENT
1171 event_defer_errno = addr->more_errno;
1172 msg_event_raise(US"msg:rcpt:host:defer", addr);
1174 /* If a 452 and we've had at least one 2xx or 5xx, set next_addr to the
1175 start point for another MAIL command. */
1177 if (addr->more_errno >> 8 == 52 && yield & 3)
1179 if (!sx->RCPT_452) /* initialised at MAIL-ack above */
1182 debug_printf("%s: seen first 452 too-many-rcpts\n", __FUNCTION__);
1183 sx->RCPT_452 = TRUE;
1184 sx->next_addr = addr;
1186 addr->transport_return = PENDING_DEFER;
1187 addr->basic_errno = 0;
1191 /* Log temporary errors if there are more hosts to be tried.
1192 If not, log this last one in the == line. */
1194 if (sx->conn_args.host->next)
1195 if (LOGGING(outgoing_port))
1196 log_write(0, LOG_MAIN, "H=%s [%s]:%d %s", sx->conn_args.host->name,
1197 sx->conn_args.host->address,
1198 sx->port == PORT_NONE ? 25 : sx->port, addr->message);
1200 log_write(0, LOG_MAIN, "H=%s [%s]: %s", sx->conn_args.host->name,
1201 sx->conn_args.host->address, addr->message);
1203 #ifndef DISABLE_EVENT
1205 msg_event_raise(US"msg:rcpt:defer", addr);
1208 /* Do not put this message on the list of those waiting for specific
1209 hosts, as otherwise it is likely to be tried too often. */
1211 update_waiting = FALSE;
1213 /* Add a retry item for the address so that it doesn't get tried again
1214 too soon. If address_retry_include_sender is true, add the sender address
1215 to the retry key. */
1217 retry_add_item(addr,
1218 ob->address_retry_include_sender
1219 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
1220 : addr->address_retry_key,
1226 if (count && !(addr = addr->next))
1228 } /* Loop for next RCPT response */
1230 /* Update where to start at for the next block of responses, unless we
1231 have already handled all the addresses. */
1233 if (addr) sx->sync_addr = addr->next;
1235 /* Handle a response to DATA. If we have not had any good recipients, either
1236 previously or in this block, the response is ignored. */
1238 if (pending_DATA != 0)
1240 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1241 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1242 '3', ob->command_timeout))
1248 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1251 if (pending_DATA > 0 || (yield & 1) != 0)
1253 if (errno == 0 && sx->buffer[0] == '4')
1255 errno = ERRNO_DATA4XX;
1256 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1260 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1261 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1262 "is in use and there were no good recipients\n", msg);
1266 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1267 present) received 3xx. If any RCPTs were handled and yielded anything other
1268 than 4xx, yield will be set non-zero. */
1277 /* Try an authenticator's client entry */
1280 try_authenticator(smtp_context * sx, auth_instance * au)
1282 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1283 host_item * host = sx->conn_args.host; /* host to deliver to */
1286 sx->outblock.authenticating = TRUE;
1287 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1288 sx->buffer, sizeof(sx->buffer));
1289 sx->outblock.authenticating = FALSE;
1290 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n", au->name, rc);
1292 /* A temporary authentication failure must hold up delivery to
1293 this host. After a permanent authentication failure, we carry on
1294 to try other authentication methods. If all fail hard, try to
1295 deliver the message unauthenticated unless require_auth was set. */
1300 f.smtp_authenticated = TRUE; /* stops the outer loop */
1301 client_authenticator = au->name;
1302 if (au->set_client_id)
1303 client_authenticated_id = expand_string(au->set_client_id);
1306 /* Failure after writing a command */
1311 /* Failure after reading a response */
1314 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1315 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1316 au->name, host->name, host->address, sx->buffer);
1319 /* Failure by some other means. In effect, the authenticator
1320 decided it wasn't prepared to handle this case. Typically this
1321 is the result of "fail" in an expansion string. Do we need to
1322 log anything here? Feb 2006: a message is now put in the buffer
1323 if logging is required. */
1326 if (*sx->buffer != 0)
1327 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1328 "authentication H=%s [%s] %s", au->name, host->name,
1329 host->address, sx->buffer);
1332 /* Internal problem, message in buffer. */
1335 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1336 DEFER, FALSE, &sx->delivery_start);
1345 /* Do the client side of smtp-level authentication.
1348 sx smtp connection context
1350 sx->buffer should have the EHLO response from server (gets overwritten)
1353 OK Success, or failed (but not required): global "smtp_authenticated" set
1354 DEFER Failed authentication (and was required)
1355 ERROR Internal problem
1357 FAIL_SEND Failed communications - transmit
1362 smtp_auth(smtp_context * sx)
1364 host_item * host = sx->conn_args.host; /* host to deliver to */
1365 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1366 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1367 #ifndef DISABLE_PIPE_CONNECT
1368 unsigned short authbits = tls_out.active.sock >= 0
1369 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1371 uschar * fail_reason = US"server did not advertise AUTH support";
1373 f.smtp_authenticated = FALSE;
1374 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1377 regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
1379 /* Is the server offering AUTH? */
1383 #ifndef DISABLE_PIPE_CONNECT
1384 sx->early_pipe_active ? authbits
1387 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1390 uschar * names = NULL;
1391 expand_nmax = -1; /* reset */
1393 #ifndef DISABLE_PIPE_CONNECT
1394 if (!sx->early_pipe_active)
1396 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1398 /* Must not do this check until after we have saved the result of the
1399 regex match above as the check could be another RE. */
1401 if ( require_auth == OK
1402 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1404 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1405 fail_reason = US"no common mechanisms were found";
1407 #ifndef DISABLE_PIPE_CONNECT
1408 if (sx->early_pipe_active)
1410 /* Scan our authenticators (which support use by a client and were offered
1411 by the server (checked at cache-write time)), not suppressed by
1412 client_condition. If one is found, attempt to authenticate by calling its
1413 client function. We are limited to supporting up to 16 authenticator
1414 public-names by the number of bits in a short. */
1420 for (bitnum = 0, au = auths;
1421 !f.smtp_authenticated && au && bitnum < 16;
1422 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1424 if ( au->client_condition
1425 && !expand_check_condition(au->client_condition, au->name,
1426 US"client authenticator"))
1428 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1429 au->name, "client_condition is false");
1433 /* Found data for a listed mechanism. Call its client entry. Set
1434 a flag in the outblock so that data is overwritten after sending so
1435 that reflections don't show it. */
1437 fail_reason = US"authentication attempt(s) failed";
1439 if ((rc = try_authenticator(sx, au)) != OK)
1446 /* Scan the configured authenticators looking for one which is configured
1447 for use as a client, which is not suppressed by client_condition, and
1448 whose name matches an authentication mechanism supported by the server.
1449 If one is found, attempt to authenticate by calling its client function.
1452 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1457 || ( au->client_condition
1458 && !expand_check_condition(au->client_condition, au->name,
1459 US"client authenticator")))
1461 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1463 (au->client)? "client_condition is false" :
1464 "not configured as a client");
1468 /* Loop to scan supported server mechanisms */
1472 int len = Ustrlen(au->public_name);
1475 while (isspace(*p)) p++;
1477 if (strncmpic(au->public_name, p, len) != 0 ||
1478 (p[len] != 0 && !isspace(p[len])))
1480 while (*p != 0 && !isspace(*p)) p++;
1484 /* Found data for a listed mechanism. Call its client entry. Set
1485 a flag in the outblock so that data is overwritten after sending so
1486 that reflections don't show it. */
1488 fail_reason = US"authentication attempt(s) failed";
1490 if ((rc = try_authenticator(sx, au)) != OK)
1493 break; /* If not authenticated, try next authenticator */
1494 } /* Loop for scanning supported server mechanisms */
1495 } /* Loop for further authenticators */
1499 /* If we haven't authenticated, but are required to, give up. */
1501 if (require_auth == OK && !f.smtp_authenticated)
1503 #ifndef DISABLE_PIPE_CONNECT
1504 invalidate_ehlo_cache_entry(sx);
1506 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1507 string_sprintf("authentication required but %s", fail_reason), DEFER,
1508 FALSE, &sx->delivery_start);
1516 /* Construct AUTH appendix string for MAIL TO */
1519 sx context for smtp connection
1520 p point in sx->buffer to build string
1521 addrlist chain of potential addresses to deliver
1523 Globals f.smtp_authenticated
1524 client_authenticated_sender
1525 Return True on error, otherwise buffer has (possibly empty) terminated string
1529 smtp_mail_auth_str(smtp_context * sx, uschar * p, address_item * addrlist)
1531 smtp_transport_options_block * ob = sx->conn_args.ob;
1532 uschar * local_authenticated_sender = authenticated_sender;
1535 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n",
1536 authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1539 if (ob->authenticated_sender)
1541 uschar * new = expand_string(ob->authenticated_sender);
1544 if (!f.expand_string_forcedfail)
1546 uschar *message = string_sprintf("failed to expand "
1547 "authenticated_sender: %s", expand_string_message);
1548 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
1553 local_authenticated_sender = new;
1556 /* Add the authenticated sender address if present */
1558 if ( (f.smtp_authenticated || ob->authenticated_sender_force)
1559 && local_authenticated_sender)
1561 string_format_nt(p, sizeof(sx->buffer) - (p-sx->buffer), " AUTH=%s",
1562 auth_xtextencode(local_authenticated_sender,
1563 Ustrlen(local_authenticated_sender)));
1564 client_authenticated_sender = string_copy(local_authenticated_sender);
1574 typedef struct smtp_compare_s
1576 uschar * current_sender_address;
1577 struct transport_instance * tblock;
1581 /* Create a unique string that identifies this message, it is based on
1582 sender_address, helo_data and tls_certificate if enabled.
1586 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1588 address_item * addr1;
1589 uschar * if1 = US"";
1590 uschar * helo1 = US"";
1592 uschar * tlsc1 = US"";
1594 uschar * save_sender_address = sender_address;
1595 uschar * local_identity = NULL;
1596 smtp_transport_options_block * ob = SOB tblock->options_block;
1598 sender_address = sender;
1600 addr1 = deliver_make_addr (sender, TRUE);
1601 deliver_set_expansions(addr1);
1604 if1 = expand_string(ob->interface);
1607 helo1 = expand_string(ob->helo_data);
1610 if (ob->tls_certificate)
1611 tlsc1 = expand_string(ob->tls_certificate);
1612 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1614 local_identity = string_sprintf ("%s^%s", if1, helo1);
1617 deliver_set_expansions(NULL);
1618 sender_address = save_sender_address;
1620 return local_identity;
1625 /* This routine is a callback that is called from transport_check_waiting.
1626 This function will evaluate the incoming message versus the previous
1627 message. If the incoming message is using a different local identity then
1628 we will veto this new message. */
1631 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1633 uschar * message_local_identity,
1634 * current_local_identity,
1635 * new_sender_address;
1637 current_local_identity =
1638 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1640 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1643 message_local_identity =
1644 smtp_local_identity(new_sender_address, s_compare->tblock);
1646 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1652 ehlo_response(uschar * buf, unsigned checks)
1654 size_t bsize = Ustrlen(buf);
1656 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1659 if ( checks & OPTION_TLS
1660 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1662 checks &= ~OPTION_TLS;
1664 if ( checks & OPTION_IGNQ
1665 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1666 PCRE_EOPT, NULL, 0) < 0)
1667 checks &= ~OPTION_IGNQ;
1669 if ( checks & OPTION_CHUNKING
1670 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1671 checks &= ~OPTION_CHUNKING;
1673 #ifndef DISABLE_PRDR
1674 if ( checks & OPTION_PRDR
1675 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1677 checks &= ~OPTION_PRDR;
1680 if ( checks & OPTION_UTF8
1681 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1683 checks &= ~OPTION_UTF8;
1685 if ( checks & OPTION_DSN
1686 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1687 checks &= ~OPTION_DSN;
1689 if ( checks & OPTION_PIPE
1690 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1691 PCRE_EOPT, NULL, 0) < 0)
1692 checks &= ~OPTION_PIPE;
1694 if ( checks & OPTION_SIZE
1695 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1696 checks &= ~OPTION_SIZE;
1698 #ifndef DISABLE_PIPE_CONNECT
1699 if ( checks & OPTION_EARLY_PIPE
1700 && pcre_exec(regex_EARLY_PIPE, NULL, CS buf, bsize, 0,
1701 PCRE_EOPT, NULL, 0) < 0)
1703 checks &= ~OPTION_EARLY_PIPE;
1705 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1711 /* Callback for emitting a BDAT data chunk header.
1713 If given a nonzero size, first flush any buffered SMTP commands
1714 then emit the command.
1716 Reap previous SMTP command responses if requested, and always reap
1717 the response from a previous BDAT command.
1720 tctx transport context
1721 chunk_size value for SMTP BDAT command
1723 tc_chunk_last add LAST option to SMTP BDAT command
1724 tc_reap_prev reap response to previous SMTP commands
1728 DEFER TLS error on first read (EHLO-resp); errno set
1732 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1735 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1736 smtp_context * sx = tctx->smtp_context;
1740 /* Write SMTP chunk header command. If not reaping responses, note that
1741 there may be more writes (like, the chunk data) done soon. */
1745 #ifndef DISABLE_PIPE_CONNECT
1746 BOOL new_conn = !!(sx->outblock.conn_args);
1748 if((cmd_count = smtp_write_command(sx,
1749 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1750 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1751 ) < 0) return ERROR;
1752 if (flags & tc_chunk_last)
1753 data_command = string_copy(big_buffer); /* Save for later error message */
1754 #ifndef DISABLE_PIPE_CONNECT
1755 /* That command write could have been the one that made the connection.
1756 Copy the fd from the client conn ctx (smtp transport specific) to the
1757 generic transport ctx. */
1760 tctx->u.fd = sx->outblock.cctx->sock;
1764 prev_cmd_count = cmd_count += sx->cmd_count;
1766 /* Reap responses for any previous, but not one we just emitted */
1770 if (sx->pending_BDAT)
1773 if (flags & tc_reap_prev && prev_cmd_count > 0)
1775 DEBUG(D_transport) debug_printf("look for %d responses"
1776 " for previous pipelined cmds\n", prev_cmd_count);
1778 switch(sync_responses(sx, prev_cmd_count, 0))
1780 case 1: /* 2xx (only) => OK */
1781 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1782 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1783 case 0: break; /* No 2xx or 5xx, but no probs */
1785 case -5: errno = ERRNO_TLSFAILURE;
1787 #ifndef DISABLE_PIPE_CONNECT
1788 case -4: /* non-2xx for pipelined banner or EHLO */
1790 case -1: /* Timeout on RCPT */
1791 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1794 if (!sx->pending_BDAT)
1795 pipelining_active = FALSE;
1798 /* Reap response for an outstanding BDAT */
1800 if (sx->pending_BDAT)
1802 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1804 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
1805 ob->command_timeout))
1807 if (errno == 0 && sx->buffer[0] == '4')
1809 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1810 sx->addrlist->more_errno |=
1811 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1816 sx->pending_BDAT = FALSE;
1817 pipelining_active = FALSE;
1819 else if (chunk_size > 0)
1820 sx->pending_BDAT = TRUE;
1823 sx->cmd_count = cmd_count;
1831 /*************************************************
1832 * Make connection for given message *
1833 *************************************************/
1837 ctx connection context
1838 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1839 a second attempt after TLS initialization fails
1841 Returns: OK - the connection was made and the delivery attempted;
1842 fd is set in the conn context, tls_out set up.
1843 DEFER - the connection could not be made, or something failed
1844 while setting up the SMTP session, or there was a
1845 non-message-specific error, such as a timeout.
1846 ERROR - helo_data or add_headers or authenticated_sender is
1847 specified for this transport, and the string failed
1851 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1853 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
1854 BOOL pass_message = FALSE;
1855 uschar * message = NULL;
1858 uschar * tls_errstr;
1861 sx->conn_args.ob = ob;
1863 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1864 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
1865 /* sx->ok = FALSE; */
1866 sx->send_rset = TRUE;
1867 sx->send_quit = TRUE;
1868 sx->setting_up = TRUE;
1870 /* sx->esmtp_sent = FALSE; */
1872 /* sx->utf8_needed = FALSE; */
1874 sx->dsn_all_lasthop = TRUE;
1876 /* sx->conn_args.dane = FALSE; */
1878 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
1880 #ifndef DISABLE_PIPE_CONNECT
1881 /* sx->early_pipe_active = sx->early_pipe_ok = FALSE; */
1882 /* sx->ehlo_resp.cleartext_features = sx->ehlo_resp.crypted_features = 0; */
1883 /* sx->pending_BANNER = sx->pending_EHLO = sx->pending_MAIL = FALSE; */
1886 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1887 /* sx->peer_offered = 0; */
1888 /* sx->avoid_option = 0; */
1889 sx->igquotstr = US"";
1890 if (!sx->helo_data) sx->helo_data = ob->helo_data;
1891 #ifdef EXPERIMENTAL_DSN_INFO
1892 /* sx->smtp_greeting = NULL; */
1893 /* sx->helo_response = NULL; */
1896 smtp_command = US"initial connection";
1897 /* sx->buffer[0] = '\0'; */
1899 /* Set up the buffer for reading SMTP response packets. */
1901 sx->inblock.buffer = sx->inbuffer;
1902 sx->inblock.buffersize = sizeof(sx->inbuffer);
1903 sx->inblock.ptr = sx->inbuffer;
1904 sx->inblock.ptrend = sx->inbuffer;
1906 /* Set up the buffer for holding SMTP commands while pipelining */
1908 sx->outblock.buffer = sx->outbuffer;
1909 sx->outblock.buffersize = sizeof(sx->outbuffer);
1910 sx->outblock.ptr = sx->outbuffer;
1911 /* sx->outblock.cmd_count = 0; */
1912 /* sx->outblock.authenticating = FALSE; */
1913 /* sx->outblock.conn_args = NULL; */
1915 /* Reset the parameters of a TLS session. */
1918 tls_out.cipher = NULL; /* the one we may use for this transport */
1919 tls_out.ourcert = NULL;
1920 tls_out.peercert = NULL;
1921 tls_out.peerdn = NULL;
1925 tls_out.ocsp = OCSP_NOT_REQ;
1926 #ifndef DISABLE_TLS_RESUME
1927 tls_out.resumption = 0;
1931 /* Flip the legacy TLS-related variables over to the outbound set in case
1932 they're used in the context of the transport. Don't bother resetting
1933 afterward (when being used by a transport) as we're in a subprocess.
1934 For verify, unflipped once the callout is dealt with */
1936 tls_modify_variables(&tls_out);
1941 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1942 DEFER, FALSE, &sx->delivery_start);
1947 /* If we have a proxied TLS connection, check usability for this message */
1949 if (continue_hostname && continue_proxy_cipher)
1952 const uschar * sni = US"";
1954 # ifdef SUPPORT_DANE
1955 /* Check if the message will be DANE-verified; if so force its SNI */
1957 tls_out.dane_verified = FALSE;
1958 smtp_port_for_connect(sx->conn_args.host, sx->port);
1959 if ( sx->conn_args.host->dnssec == DS_YES
1960 && ( sx->dane_required
1961 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
1963 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
1965 case OK: sx->conn_args.dane = TRUE;
1966 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
1967 ob->tls_sni = sx->first_addr->domain; /* force SNI */
1969 case FAIL_FORCED: break;
1970 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1971 string_sprintf("DANE error: tlsa lookup %s",
1973 rc, FALSE, &sx->delivery_start);
1974 # ifndef DISABLE_EVENT
1975 (void) event_raise(sx->conn_args.tblock->event_action,
1976 US"dane:fail", sx->dane_required
1977 ? US"dane-required" : US"dnssec-invalid");
1983 /* If the SNI or the DANE status required for the new message differs from the
1984 existing conn drop the connection to force a new one. */
1986 if (ob->tls_sni && !(sni = expand_cstring(ob->tls_sni)))
1987 log_write(0, LOG_MAIN|LOG_PANIC,
1988 "<%s>: failed to expand transport's tls_sni value: %s",
1989 sx->addrlist->address, expand_string_message);
1991 # ifdef SUPPORT_DANE
1992 if ( (continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni)
1993 && continue_proxy_dane == sx->conn_args.dane)
1995 tls_out.sni = US sni;
1996 if ((tls_out.dane_verified = continue_proxy_dane))
1997 sx->conn_args.host->dnssec = DS_YES;
2000 if ((continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni))
2001 tls_out.sni = US sni;
2006 debug_printf("Closing proxied-TLS connection due to SNI mismatch\n");
2008 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP>> QUIT\n");
2009 write(0, "QUIT\r\n", 6);
2011 continue_hostname = continue_proxy_cipher = NULL;
2012 f.continue_more = FALSE;
2013 continue_sequence = 1; /* Unfortunately, this process cannot affect success log
2014 which is done by delivery proc. Would have to pass this
2015 back through reporting pipe. */
2018 #endif /*!DISABLE_TLS*/
2020 /* Make a connection to the host if this isn't a continued delivery, and handle
2021 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2022 specially so they can be identified for retries. */
2024 if (!continue_hostname)
2027 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2029 /* Get the actual port the connection will use, into sx->conn_args.host */
2031 smtp_port_for_connect(sx->conn_args.host, sx->port);
2034 /* Do TLSA lookup for DANE */
2036 tls_out.dane_verified = FALSE;
2037 tls_out.tlsa_usage = 0;
2039 if (sx->conn_args.host->dnssec == DS_YES)
2042 if( sx->dane_required
2043 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2045 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2047 case OK: sx->conn_args.dane = TRUE;
2048 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2049 ob->tls_sni = sx->first_addr->domain; /* force SNI */
2051 case FAIL_FORCED: break;
2052 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2053 string_sprintf("DANE error: tlsa lookup %s",
2055 rc, FALSE, &sx->delivery_start);
2056 # ifndef DISABLE_EVENT
2057 (void) event_raise(sx->conn_args.tblock->event_action,
2058 US"dane:fail", sx->dane_required
2059 ? US"dane-required" : US"dnssec-invalid");
2064 else if (sx->dane_required)
2066 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2067 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2068 FAIL, FALSE, &sx->delivery_start);
2069 # ifndef DISABLE_EVENT
2070 (void) event_raise(sx->conn_args.tblock->event_action,
2071 US"dane:fail", US"dane-required");
2078 /* Make the TCP connection */
2080 sx->cctx.tls_ctx = NULL;
2081 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2082 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2084 #ifndef DISABLE_PIPE_CONNECT
2085 if ( verify_check_given_host(CUSS &ob->hosts_pipe_connect,
2086 sx->conn_args.host) == OK)
2088 /* We don't find out the local ip address until the connect, so if
2089 the helo string might use it avoid doing early-pipelining. */
2092 || !Ustrstr(sx->helo_data, "$sending_ip_address")
2093 || Ustrstr(sx->helo_data, "def:sending_ip_address")
2096 sx->early_pipe_ok = TRUE;
2097 if ( read_ehlo_cache_entry(sx)
2098 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2101 debug_printf("Using cached cleartext PIPE_CONNECT\n");
2102 sx->early_pipe_active = TRUE;
2103 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2106 else DEBUG(D_transport)
2107 debug_printf("helo needs $sending_ip_address\n");
2110 if (sx->early_pipe_active)
2111 sx->outblock.conn_args = &sx->conn_args;
2115 blob lazy_conn = {.data = NULL};
2116 /* For TLS-connect, a TFO lazy-connect is useful since the Client Hello
2117 can go on the TCP SYN. */
2119 if ((sx->cctx.sock = smtp_connect(&sx->conn_args,
2120 sx->smtps ? &lazy_conn : NULL)) < 0)
2122 set_errno_nohost(sx->addrlist,
2123 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2124 sx->verify ? US strerror(errno) : NULL,
2125 DEFER, FALSE, &sx->delivery_start);
2126 sx->send_quit = FALSE;
2130 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2134 /* Expand the greeting message while waiting for the initial response. (Makes
2135 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2136 delayed till here so that $sending_interface and $sending_port are set. */
2137 /*XXX early-pipe: they still will not be. Is there any way to find out what they
2138 will be? Somehow I doubt it. */
2141 if (!(sx->helo_data = expand_string(sx->helo_data)))
2143 log_write(0, LOG_MAIN|LOG_PANIC,
2144 "<%s>: failed to expand transport's helo_data value for callout: %s",
2145 sx->addrlist->address, expand_string_message);
2150 expand_string_message = NULL;
2151 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2152 &expand_string_message)),
2153 expand_string_message)
2155 log_write(0, LOG_MAIN|LOG_PANIC,
2156 "<%s>: failed to expand transport's helo_data value for callout: %s",
2157 sx->addrlist->address, expand_string_message);
2159 sx->helo_data = NULL;
2163 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2164 is nevertheless a reasonably clean way of programming this kind of logic,
2165 where you want to escape on any error. */
2169 #ifndef DISABLE_PIPE_CONNECT
2170 if (sx->early_pipe_active)
2172 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2173 sx->outblock.cmd_count = 1;
2178 if (!smtp_reap_banner(sx))
2179 goto RESPONSE_FAILED;
2182 #ifndef DISABLE_EVENT
2185 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2186 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2187 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer);
2190 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2191 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2192 DEFER, FALSE, &sx->delivery_start);
2199 /* Now check if the helo_data expansion went well, and sign off cleanly if
2204 message = string_sprintf("failed to expand helo_data: %s",
2205 expand_string_message);
2206 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2212 /** Debugging without sending a message
2213 sx->addrlist->transport_return = DEFER;
2217 /* Errors that occur after this point follow an SMTP command, which is
2218 left in big_buffer by smtp_write_command() for use in error messages. */
2220 smtp_command = big_buffer;
2222 /* Tell the remote who we are...
2224 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2225 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2226 greeting is of this form. The assumption was that the far end supports it
2227 properly... but experience shows that there are some that give 5xx responses,
2228 even though the banner includes "ESMTP" (there's a bloody-minded one that
2229 says "ESMTP not spoken here"). Cope with that case.
2231 September 2000: Time has passed, and it seems reasonable now to always send
2232 EHLO at the start. It is also convenient to make the change while installing
2235 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2236 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2237 would be no way to send out the mails, so there is now a host list
2238 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2239 PIPELINING problem as well. Maybe it can also be useful to cure other
2240 problems with broken servers.
2242 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2243 Then somebody tried it with a Microsoft mailer... It seems that all other
2244 mailers use upper case for some reason (the RFC is quite clear about case
2245 independence) so, for peace of mind, I gave in. */
2247 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2249 /* Alas; be careful, since this goto is not an error-out, so conceivably
2250 we might set data between here and the target which we assume to exist
2251 and be usable. I can see this coming back to bite us. */
2255 smtp_peer_options |= OPTION_TLS;
2256 suppress_tls = FALSE;
2257 ob->tls_tempfail_tryclear = FALSE;
2258 smtp_command = US"SSL-on-connect";
2265 if (smtp_write_command(sx,
2266 #ifndef DISABLE_PIPE_CONNECT
2267 sx->early_pipe_active ? SCMD_BUFFER :
2270 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2272 sx->esmtp_sent = TRUE;
2274 #ifndef DISABLE_PIPE_CONNECT
2275 if (sx->early_pipe_active)
2277 sx->pending_EHLO = TRUE;
2279 /* If we have too many authenticators to handle and might need to AUTH
2280 for this transport, pipeline no further as we will need the
2281 list of auth methods offered. Reap the banner and EHLO. */
2283 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2284 && f.smtp_in_early_pipe_no_auth)
2286 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2287 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2289 if (sync_responses(sx, 2, 0) != 0)
2292 debug_printf("failed reaping pipelined cmd responses\n");
2293 goto RESPONSE_FAILED;
2295 sx->early_pipe_active = FALSE;
2300 if (!smtp_reap_ehlo(sx))
2301 goto RESPONSE_FAILED;
2305 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2307 #ifndef DISABLE_PIPE_CONNECT
2308 if (!sx->early_pipe_active)
2313 int n = sizeof(sx->buffer);
2314 uschar * rsp = sx->buffer;
2316 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
2317 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
2319 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2321 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2322 #ifdef EXPERIMENTAL_DSN_INFO
2323 sx->helo_response = string_copy(rsp);
2327 /* Handle special logging for a closed connection after HELO
2328 when had previously sent EHLO */
2330 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2332 errno = ERRNO_SMTPCLOSED;
2333 goto EHLOHELO_FAILED;
2335 memmove(sx->buffer, rsp, Ustrlen(rsp));
2336 goto RESPONSE_FAILED;
2340 if (sx->esmtp || sx->lmtp)
2342 #ifndef DISABLE_PIPE_CONNECT
2343 if (!sx->early_pipe_active)
2346 sx->peer_offered = ehlo_response(sx->buffer,
2347 OPTION_TLS /* others checked later */
2348 #ifndef DISABLE_PIPE_CONNECT
2349 | (sx->early_pipe_ok
2351 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2360 #ifndef DISABLE_PIPE_CONNECT
2361 if (sx->early_pipe_ok)
2363 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2365 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2366 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2368 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2369 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2370 write_ehlo_cache_entry(sx);
2376 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2379 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2384 /* For continuing deliveries down the same channel, having re-exec'd the socket
2385 is the standard input; for a socket held open from verify it is recorded
2386 in the cutthrough context block. Either way we don't need to redo EHLO here
2387 (but may need to do so for TLS - see below).
2388 Set up the pointer to where subsequent commands will be left, for
2389 error messages. Note that smtp_peer_options will have been
2390 set from the command line if they were set in the process that passed the
2393 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2394 as the continue goes via transport_pass_socket() and doublefork and exec.
2395 It does not wait. Unclear how we keep separate host's responses
2396 separate - we could match up by host ip+port as a bodge. */
2400 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2402 sx->cctx = cutthrough.cctx;
2403 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2407 sx->cctx.sock = 0; /* stdin */
2408 sx->cctx.tls_ctx = NULL;
2409 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2411 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2412 smtp_command = big_buffer;
2413 sx->peer_offered = smtp_peer_options;
2414 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2416 /* For a continued connection with TLS being proxied for us, or a
2417 held-open verify connection with TLS, nothing more to do. */
2419 if ( continue_proxy_cipher
2420 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2421 && cutthrough.is_tls)
2424 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2425 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2426 continue_proxy_cipher ? "proxied" : "verify conn with");
2429 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2432 /* If TLS is available on this connection, whether continued or not, attempt to
2433 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2434 send another EHLO - the server may give a different answer in secure mode. We
2435 use a separate buffer for reading the response to STARTTLS so that if it is
2436 negative, the original EHLO data is available for subsequent analysis, should
2437 the client not be required to use TLS. If the response is bad, copy the buffer
2438 for error analysis. */
2441 if ( smtp_peer_options & OPTION_TLS
2443 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2445 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2448 uschar buffer2[4096];
2450 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2453 #ifndef DISABLE_PIPE_CONNECT
2454 /* If doing early-pipelining reap the banner and EHLO-response but leave
2455 the response for the STARTTLS we just sent alone. */
2457 if (sx->early_pipe_active && sync_responses(sx, 2, 0) != 0)
2460 debug_printf("failed reaping pipelined cmd responses\n");
2461 close(sx->cctx.sock);
2463 sx->early_pipe_active = FALSE;
2464 goto PIPE_CONNECT_RETRY;
2468 /* If there is an I/O error, transmission of this message is deferred. If
2469 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2470 false, we also defer. However, if there is a temporary rejection of STARTTLS
2471 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2472 STARTTLS, we carry on. This means we will try to send the message in clear,
2473 unless the host is in hosts_require_tls (tested below). */
2475 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2479 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2482 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2483 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2484 goto RESPONSE_FAILED;
2488 /* STARTTLS accepted: try to negotiate a TLS session. */
2493 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2495 /* TLS negotiation failed; give an error. From outside, this function may
2496 be called again to try in clear on a new connection, if the options permit
2497 it for this host. */
2499 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2501 # ifdef SUPPORT_DANE
2502 if (sx->conn_args.dane)
2504 log_write(0, LOG_MAIN,
2505 "DANE attempt failed; TLS connection to %s [%s]: %s",
2506 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2507 # ifndef DISABLE_EVENT
2508 (void) event_raise(sx->conn_args.tblock->event_action,
2509 US"dane:fail", US"validation-failure"); /* could do with better detail */
2514 errno = ERRNO_TLSFAILURE;
2515 message = string_sprintf("TLS session: %s", tls_errstr);
2516 sx->send_quit = FALSE;
2520 /* TLS session is set up. Check the inblock fill level. If there is
2521 content then as we have not yet done a tls read it must have arrived before
2522 the TLS handshake, in-clear. That violates the sync requirement of the
2523 STARTTLS RFC, so fail. */
2525 if (sx->inblock.ptr != sx->inblock.ptrend)
2529 int i = sx->inblock.ptrend - sx->inblock.ptr;
2530 debug_printf("unused data in input buffer after ack for STARTTLS:\n"
2532 i > 100 ? 100 : i, sx->inblock.ptr, i > 100 ? "..." : "");
2534 tls_errstr = US"synch error before connect";
2535 goto TLS_CONN_FAILED;
2538 smtp_peer_options_wrap = smtp_peer_options;
2539 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2540 if (addr->transport_return == PENDING_DEFER)
2542 addr->cipher = tls_out.cipher;
2543 addr->ourcert = tls_out.ourcert;
2544 addr->peercert = tls_out.peercert;
2545 addr->peerdn = tls_out.peerdn;
2546 addr->ocsp = tls_out.ocsp;
2547 addr->tlsver = tls_out.ver;
2552 /* if smtps, we'll have smtp_command set to something else; always safe to
2554 smtp_command = big_buffer;
2556 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2557 helo_data is null, we are dealing with a connection that was passed from
2558 another process, and so we won't have expanded helo_data above. We have to
2559 expand it here. $sending_ip_address and $sending_port are set up right at the
2560 start of the Exim process (in exim.c). */
2562 if (tls_out.active.sock >= 0)
2564 uschar * greeting_cmd;
2566 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2568 uschar *message = string_sprintf("failed to expand helo_data: %s",
2569 expand_string_message);
2570 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2575 #ifndef DISABLE_PIPE_CONNECT
2576 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2577 We're unlikely to get the group sent and delivered before the server sends its
2578 banner, but it's still worth sending as a group.
2579 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2582 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2584 sx->peer_offered = sx->ehlo_resp.crypted_features;
2585 if ((sx->early_pipe_active =
2586 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2587 DEBUG(D_transport) debug_printf("Using cached crypted PIPE_CONNECT\n");
2591 /* For SMTPS we need to wait for the initial OK response. */
2593 #ifndef DISABLE_PIPE_CONNECT
2594 if (sx->early_pipe_active)
2596 sx->pending_BANNER = TRUE;
2597 sx->outblock.cmd_count = 1;
2601 if (!smtp_reap_banner(sx))
2602 goto RESPONSE_FAILED;
2605 greeting_cmd = US"LHLO";
2607 greeting_cmd = US"EHLO";
2610 greeting_cmd = US"HELO";
2612 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2615 if (smtp_write_command(sx,
2616 #ifndef DISABLE_PIPE_CONNECT
2617 sx->early_pipe_active ? SCMD_BUFFER :
2620 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2623 #ifndef DISABLE_PIPE_CONNECT
2624 if (sx->early_pipe_active)
2625 sx->pending_EHLO = TRUE;
2629 if (!smtp_reap_ehlo(sx))
2632 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2633 cert late, under TLS1.3 - which means here; the first time we try to
2634 receive crypted data. Treat it as if it was a connect-time failure.
2635 See also the early-pipe equivalent... which will be hard; every call
2636 to sync_responses will need to check the result.
2637 It would be nicer to have GnuTLS check the cert during the handshake.
2638 Can it do that, with all the flexibility we need? */
2640 tls_errstr = US"error on first read";
2641 goto TLS_CONN_FAILED;
2644 goto RESPONSE_FAILED;
2646 smtp_peer_options = 0;
2650 /* If the host is required to use a secure channel, ensure that we
2654 # ifdef SUPPORT_DANE
2655 || sx->conn_args.dane
2657 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2660 errno = ERRNO_TLSREQUIRED;
2661 message = string_sprintf("a TLS session is required, but %s",
2662 smtp_peer_options & OPTION_TLS
2663 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2664 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2665 if (sx->conn_args.dane)
2666 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2667 smtp_peer_options & OPTION_TLS
2668 ? US"validation-failure" /* could do with better detail */
2669 : US"starttls-not-supported");
2673 #endif /*DISABLE_TLS*/
2675 /* If TLS is active, we have just started it up and re-done the EHLO command,
2676 so its response needs to be analyzed. If TLS is not active and this is a
2677 continued session down a previously-used socket, we haven't just done EHLO, so
2680 if ( !continue_hostname
2682 || tls_out.active.sock >= 0
2686 if (sx->esmtp || sx->lmtp)
2688 #ifndef DISABLE_PIPE_CONNECT
2689 if (!sx->early_pipe_active)
2692 sx->peer_offered = ehlo_response(sx->buffer,
2694 #ifndef DISABLE_PIPE_CONNECT
2695 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2696 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2697 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2698 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2702 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2705 # ifdef SUPPORT_I18N
2706 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2707 /*XXX if we hand peercaps on to continued-conn processes,
2708 must not depend on this addr */
2712 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2715 #ifndef DISABLE_PIPE_CONNECT
2716 if (tls_out.active.sock >= 0)
2717 sx->ehlo_resp.crypted_features = sx->peer_offered;
2721 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2722 lmtp_ignore_quota option was set. */
2724 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2726 /* If the response to EHLO specified support for the SIZE parameter, note
2727 this, provided size_addition is non-negative. */
2729 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2731 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2732 the current host, esmtp will be false, so PIPELINING can never be used. If
2733 the current host matches hosts_avoid_pipelining, don't do it. */
2735 if ( sx->peer_offered & OPTION_PIPE
2736 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2737 smtp_peer_options |= OPTION_PIPE;
2739 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2740 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2742 if ( sx->peer_offered & OPTION_CHUNKING
2743 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) != OK)
2744 sx->peer_offered &= ~OPTION_CHUNKING;
2746 if (sx->peer_offered & OPTION_CHUNKING)
2747 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2749 #ifndef DISABLE_PRDR
2750 if ( sx->peer_offered & OPTION_PRDR
2751 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) != OK)
2752 sx->peer_offered &= ~OPTION_PRDR;
2754 if (sx->peer_offered & OPTION_PRDR)
2755 DEBUG(D_transport) debug_printf("PRDR usable\n");
2758 /* Note if the server supports DSN */
2759 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2760 DEBUG(D_transport) debug_printf("%susing DSN\n",
2761 sx->peer_offered & OPTION_DSN ? "" : "not ");
2763 #ifndef DISABLE_PIPE_CONNECT
2764 if ( sx->early_pipe_ok
2765 && !sx->early_pipe_active
2766 && tls_out.active.sock >= 0
2767 && smtp_peer_options & OPTION_PIPE
2768 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
2769 & OPTION_EARLY_PIPE)
2771 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2772 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
2773 write_ehlo_cache_entry(sx);
2777 /* Note if the response to EHLO specifies support for the AUTH extension.
2778 If it has, check that this host is one we want to authenticate to, and do
2779 the business. The host name and address must be available when the
2780 authenticator's client driver is running. */
2782 switch (yield = smtp_auth(sx))
2784 default: goto SEND_QUIT;
2786 case FAIL_SEND: goto SEND_FAILED;
2787 case FAIL: goto RESPONSE_FAILED;
2791 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2793 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2794 message-specific. */
2796 sx->setting_up = FALSE;
2799 if (sx->addrlist->prop.utf8_msg)
2803 /* If the transport sets a downconversion mode it overrides any set by ACL
2806 if ((s = ob->utf8_downconvert))
2808 if (!(s = expand_string(s)))
2810 message = string_sprintf("failed to expand utf8_downconvert: %s",
2811 expand_string_message);
2812 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2818 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
2819 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2821 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
2822 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2824 case '-': if (s[1] == '1')
2826 sx->addrlist->prop.utf8_downcvt = FALSE;
2827 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
2833 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2834 && !sx->addrlist->prop.utf8_downcvt_maybe;
2835 DEBUG(D_transport) if (!sx->utf8_needed)
2836 debug_printf("utf8: %s downconvert\n",
2837 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2840 /* If this is an international message we need the host to speak SMTPUTF8 */
2841 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2843 errno = ERRNO_UTF8_FWD;
2844 goto RESPONSE_FAILED;
2846 #endif /*SUPPORT_I18N*/
2855 if (errno == ECONNREFUSED) /* first-read error on a TFO conn */
2857 /* There is a testing facility for simulating a connection timeout, as I
2858 can't think of any other way of doing this. It converts a connection
2859 refused into a timeout if the timeout is set to 999999. This is done for
2860 a 3whs connection in ip_connect(), but a TFO connection does not error
2861 there - instead it gets ECONNREFUSED on the first data read. Tracking
2862 that a TFO really was done is too hard, or we would set a
2863 sx->pending_conn_done bit and test that in smtp_reap_banner() and
2864 smtp_reap_ehlo(). That would let us also add the conn-timeout to the
2867 if (f.running_in_test_harness && ob->connect_timeout == 999999)
2869 set_errno_nohost(sx->addrlist,
2870 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2871 sx->verify ? US strerror(errno) : NULL,
2872 DEFER, FALSE, &sx->delivery_start);
2873 sx->send_quit = FALSE;
2877 /* really an error on an SMTP read */
2879 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
2880 sx->buffer, &code, &message, &pass_message);
2886 message = US string_sprintf("send() to %s [%s] failed: %s",
2887 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
2888 sx->send_quit = FALSE;
2894 message = string_sprintf("Remote host closed connection in response to %s"
2895 " (EHLO response was: %s)", smtp_command, sx->buffer);
2896 sx->send_quit = FALSE;
2900 /* This label is jumped to directly when a TLS negotiation has failed,
2901 or was not done for a host for which it is required. Values will be set
2902 in message and errno, and setting_up will always be true. Treat as
2903 a temporary error. */
2907 code = '4', yield = DEFER;
2911 /* The failure happened while setting up the call; see if the failure was
2912 a 5xx response (this will either be on connection, or following HELO - a 5xx
2913 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2914 fail all addresses, as this host is never going to accept them. For other
2915 errors during setting up (timeouts or whatever), defer all addresses, and
2916 yield DEFER, so that the host is not tried again for a while.
2918 XXX This peeking for another host feels like a layering violation. We want
2919 to note the host as unusable, but down here we shouldn't know if this was
2920 the last host to try for the addr(list). Perhaps the upper layer should be
2921 the one to do set_errno() ? The problem is that currently the addr is where
2922 errno etc. are stashed, but until we run out of hosts to try the errors are
2923 host-specific. Maybe we should enhance the host_item definition? */
2926 sx->ok = FALSE; /* For when reached by GOTO */
2927 set_errno(sx->addrlist, errno, message,
2928 sx->conn_args.host->next
2932 || errno == ERRNO_UTF8_FWD
2936 errno == ECONNREFUSED ? NULL : sx->conn_args.host,
2937 #ifdef EXPERIMENTAL_DSN_INFO
2938 sx->smtp_greeting, sx->helo_response,
2940 &sx->delivery_start);
2947 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
2950 if (sx->cctx.tls_ctx)
2952 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
2953 sx->cctx.tls_ctx = NULL;
2957 /* Close the socket, and return the appropriate value, first setting
2958 works because the NULL setting is passed back to the calling process, and
2959 remote_max_parallel is forced to 1 when delivering over an existing connection,
2962 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2965 shutdown(sx->cctx.sock, SHUT_WR);
2966 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
2967 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
2968 i--; /* drain socket */
2969 sx->send_quit = FALSE;
2971 (void)close(sx->cctx.sock);
2974 #ifndef DISABLE_EVENT
2975 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL);
2978 continue_transport = NULL;
2979 continue_hostname = NULL;
2986 /* Create the string of options that will be appended to the MAIL FROM:
2987 in the connection context buffer */
2990 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2992 uschar * p = sx->buffer;
2993 address_item * addr;
2998 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2999 send it, adding something to the message size to allow for imprecision
3000 and things that get added en route. Exim keeps the number of lines
3001 in a message, so we can give an accurate value for the original message, but we
3002 need some additional to handle added headers. (Double "." characters don't get
3003 included in the count.) */
3005 if ( message_size > 0
3006 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
3008 /*XXX problem here under spool_files_wireformat?
3009 Or just forget about lines? Or inflate by a fixed proportion? */
3011 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
3015 #ifndef DISABLE_PRDR
3016 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
3019 sx->prdr_active = FALSE;
3020 if (sx->peer_offered & OPTION_PRDR)
3021 for (address_item * addr = addrlist; addr; addr = addr->next)
3022 if (addr->transport_return == PENDING_DEFER)
3024 for (addr = addr->next; addr; addr = addr->next)
3025 if (addr->transport_return == PENDING_DEFER)
3026 { /* at least two recipients to send */
3027 sx->prdr_active = TRUE;
3028 sprintf(CS p, " PRDR"); p += 5;
3036 /* If it supports internationalised messages, and this meesage need that,
3039 if ( sx->peer_offered & OPTION_UTF8
3040 && addrlist->prop.utf8_msg
3041 && !addrlist->prop.utf8_downcvt
3043 Ustrcpy(p, US" SMTPUTF8"), p += 9;
3046 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3047 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3048 addr && address_count < sx->max_rcpt;
3049 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3052 if (!(addr->dsn_flags & rf_dsnlasthop))
3054 sx->dsn_all_lasthop = FALSE;
3059 /* Add any DSN flags to the mail command */
3061 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3063 if (dsn_ret == dsn_ret_hdrs)
3064 { Ustrcpy(p, US" RET=HDRS"); p += 9; }
3065 else if (dsn_ret == dsn_ret_full)
3066 { Ustrcpy(p, US" RET=FULL"); p += 9; }
3070 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3075 /* If an authenticated_sender override has been specified for this transport
3076 instance, expand it. If the expansion is forced to fail, and there was already
3077 an authenticated_sender for this message, the original value will be used.
3078 Other expansion failures are serious. An empty result is ignored, but there is
3079 otherwise no check - this feature is expected to be used with LMTP and other
3080 cases where non-standard addresses (e.g. without domains) might be required. */
3082 return smtp_mail_auth_str(sx, p, addrlist) ? ERROR : OK;
3087 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3089 uschar * p = sx->buffer;
3092 /* Add any DSN flags to the rcpt command */
3094 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3096 if (addr->dsn_flags & rf_dsnflags)
3100 Ustrcpy(p, US" NOTIFY=");
3102 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3104 if (!first) *p++ = ',';
3106 Ustrcpy(p, rf_names[i]);
3111 if (addr->dsn_orcpt)
3113 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3124 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3125 -1 MAIL response error
3126 -2 any non-MAIL read i/o error
3127 -3 non-MAIL response timeout
3128 -4 internal error; channel still usable
3133 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3135 address_item * addr;
3136 int address_count, pipe_limit;
3139 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3145 /* From here until we send the DATA command, we can make use of PIPELINING
3146 if the server host supports it. The code has to be able to check the responses
3147 at any point, for when the buffer fills up, so we write it totally generally.
3148 When PIPELINING is off, each command written reports that it has flushed the
3151 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3154 uschar * s = sx->from_addr;
3156 uschar * errstr = NULL;
3158 /* If we must downconvert, do the from-address here. Remember we had to
3159 for the to-addresses (done below), and also (ugly) for re-doing when building
3160 the delivery log line. */
3162 if ( sx->addrlist->prop.utf8_msg
3163 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3166 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3168 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, &sx->delivery_start);
3172 setflag(sx->addrlist, af_utf8_downcvt);
3176 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3177 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3180 mail_command = string_copy(big_buffer); /* Save for later error message */
3184 case -1: /* Transmission error */
3187 case +1: /* Cmd was sent */
3188 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3189 (SOB sx->conn_args.ob)->command_timeout))
3191 if (errno == 0 && sx->buffer[0] == '4')
3193 errno = ERRNO_MAIL4XX;
3194 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3198 sx->pending_MAIL = FALSE;
3201 /* otherwise zero: command queued for pipeline */
3204 /* Pass over all the relevant recipient addresses for this host, which are the
3205 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3206 several before we have to read the responses for those seen so far. This
3207 checking is done by a subroutine because it also needs to be done at the end.
3208 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3209 the next one if not all are sent.
3211 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3212 last address because we want to abort if any recipients have any kind of
3213 problem, temporary or permanent. We know that all recipient addresses will have
3214 the PENDING_DEFER status, because only one attempt is ever made, and we know
3215 that max_rcpt will be large, so all addresses will be done at once.
3217 For verify we flush the pipeline after any (the only) rcpt address. */
3219 for (addr = sx->first_addr, address_count = 0, pipe_limit = 100;
3220 addr && address_count < sx->max_rcpt;
3221 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3227 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3228 ? dsn_support_yes : dsn_support_no;
3231 if (pipe_limit-- <= 0)
3232 { no_flush = FALSE; pipe_limit = 100; }
3234 no_flush = pipelining_active && !sx->verify
3235 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3237 build_rcptcmd_options(sx, addr);
3239 /* Now send the RCPT command, and process outstanding responses when
3240 necessary. After a timeout on RCPT, we just end the function, leaving the
3241 yield as OK, because this error can often mean that there is a problem with
3242 just one address, so we don't want to delay the host. */
3244 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3247 if ( testflag(sx->addrlist, af_utf8_downcvt)
3248 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3251 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3252 errno = ERRNO_EXPANDFAIL;
3253 return -5; /*XXX too harsh? */
3257 cmds_sent = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3258 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3260 if (cmds_sent < 0) return -5;
3263 switch(sync_responses(sx, cmds_sent, 0))
3265 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3266 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3269 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3270 if (!sx->lmtp) /* can't tell about progress yet */
3271 sx->completed_addr = TRUE;
3272 case 0: /* No 2xx or 5xx, but no probs */
3273 /* If any RCPT got a 452 response then next_addr has been updated
3274 for restarting with a new MAIL on the same connection. Send no more
3275 RCPTs for this MAIL. */
3279 DEBUG(D_transport) debug_printf("seen 452 too-many-rcpts\n");
3280 sx->RCPT_452 = FALSE;
3281 /* sx->next_addr has been reset for fast_retry */
3286 case -1: return -3; /* Timeout on RCPT */
3287 case -2: return -2; /* non-MAIL read i/o error */
3288 default: return -1; /* any MAIL error */
3290 #ifndef DISABLE_PIPE_CONNECT
3291 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3292 case -5: return -1; /* TLS first-read error */
3296 } /* Loop for next address */
3298 sx->next_addr = addr;
3304 /*****************************************************
3305 * Proxy TLS connection for another transport process *
3306 ******************************************************/
3308 Close the unused end of the pipe, fork once more, then use the given buffer
3309 as a staging area, and select on both the given fd and the TLS'd client-fd for
3310 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3311 Do blocking full-size writes, and reads under a timeout. Once both input
3312 channels are closed, exit the process.
3316 buf space to use for buffering
3317 bufsiz size of buffer
3318 pfd pipe filedescriptor array; [0] is comms to proxied process
3319 timeout per-read timeout, seconds
3325 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3329 int max_fd = MAX(pfd[0], tls_out.active.sock) + 1;
3333 if ((rc = exim_fork(US"tls-proxy")))
3334 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3336 set_process_info("proxying TLS connection for continued transport");
3338 FD_SET(tls_out.active.sock, &rfds);
3339 FD_SET(pfd[0], &rfds);
3341 for (int fd_bits = 3; fd_bits; )
3343 time_t time_left = timeout;
3344 time_t time_start = time(NULL);
3350 struct timeval tv = { time_left, 0 };
3353 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
3355 if (rc < 0 && errno == EINTR)
3356 if ((time_left -= time(NULL) - time_start) > 0) continue;
3360 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3364 if (FD_ISSET(tls_out.active.sock, &efds) || FD_ISSET(pfd[0], &efds))
3366 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3367 FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
3371 while (rc < 0 || !(FD_ISSET(tls_out.active.sock, &rfds) || FD_ISSET(pfd[0], &rfds)));
3373 /* handle inbound data */
3374 if (FD_ISSET(tls_out.active.sock, &rfds))
3375 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0)
3378 FD_CLR(tls_out.active.sock, &rfds);
3379 shutdown(pfd[0], SHUT_WR);
3384 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3385 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3387 else if (fd_bits & 1)
3388 FD_SET(tls_out.active.sock, &rfds);
3390 /* handle outbound data */
3391 if (FD_ISSET(pfd[0], &rfds))
3392 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3395 tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3400 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3401 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3404 else if (fd_bits & 2)
3405 FD_SET(pfd[0], &rfds);
3409 testharness_pause_ms(100); /* let logging complete */
3410 exim_exit(EXIT_SUCCESS);
3415 /*************************************************
3416 * Deliver address list to given host *
3417 *************************************************/
3419 /* If continue_hostname is not null, we get here only when continuing to
3420 deliver down an existing channel. The channel was passed as the standard
3421 input. TLS is never active on a passed channel; the previous process either
3422 closes it down before passing the connection on, or inserts a TLS-proxy
3423 process and passes on a cleartext conection.
3425 Otherwise, we have to make a connection to the remote host, and do the
3426 initial protocol exchange.
3428 When running as an MUA wrapper, if the sender or any recipient is rejected,
3429 temporarily or permanently, we force failure for all recipients.
3432 addrlist chain of potential addresses to deliver; only those whose
3433 transport_return field is set to PENDING_DEFER are currently
3434 being processed; others should be skipped - they have either
3435 been delivered to an earlier host or IP address, or been
3436 failed by one of them.
3437 host host to deliver to
3438 host_af AF_INET or AF_INET6
3439 defport default TCP/IP port to use if host does not specify, in host
3441 interface interface to bind to, or NULL
3442 tblock transport instance block
3443 message_defer set TRUE if yield is OK, but all addresses were deferred
3444 because of a non-recipient, non-host failure, that is, a
3445 4xx response to MAIL FROM, DATA, or ".". This is a defer
3446 that is specific to the message.
3447 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3448 a second attempt after TLS initialization fails
3450 Returns: OK - the connection was made and the delivery attempted;
3451 the result for each address is in its data block.
3452 DEFER - the connection could not be made, or something failed
3453 while setting up the SMTP session, or there was a
3454 non-message-specific error, such as a timeout.
3455 ERROR - a filter command is specified for this transport,
3456 and there was a problem setting it up; OR helo_data
3457 or add_headers or authenticated_sender is specified
3458 for this transport, and the string failed to expand
3460 For all non-OK returns the first addr of the list carries the
3461 time taken for the attempt.
3465 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3466 uschar *interface, transport_instance *tblock,
3467 BOOL *message_defer, BOOL suppress_tls)
3469 smtp_transport_options_block * ob = SOB tblock->options_block;
3474 BOOL pass_message = FALSE;
3475 uschar *message = NULL;
3476 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3477 smtp_context * sx = store_get(sizeof(*sx), TRUE); /* tainted, for the data buffers */
3482 *message_defer = FALSE;
3484 memset(sx, 0, sizeof(*sx));
3485 sx->addrlist = addrlist;
3486 sx->conn_args.host = host;
3487 sx->conn_args.host_af = host_af,
3489 sx->conn_args.interface = interface;
3490 sx->helo_data = NULL;
3491 sx->conn_args.tblock = tblock;
3492 /* sx->verify = FALSE; */
3493 gettimeofday(&sx->delivery_start, NULL);
3494 sx->sync_addr = sx->first_addr = addrlist;
3501 /* Get the channel set up ready for a message, MAIL FROM being the next
3502 SMTP command to send. */
3504 if ((rc = smtp_setup_conn(sx, suppress_tls)) != OK)
3506 timesince(&addrlist->delivery_time, &sx->delivery_start);
3512 /* If the connection used DANE, ignore for now any addresses with incompatible
3513 domains. The SNI has to be the domain. Arrange a whole new TCP conn later,
3514 just in case only TLS isn't enough. */
3516 if (sx->conn_args.dane)
3518 const uschar * dane_domain = sx->first_addr->domain;
3520 for (address_item * a = sx->first_addr->next; a; a = a->next)
3521 if ( a->transport_return == PENDING_DEFER
3522 && Ustrcmp(dane_domain, a->domain) != 0)
3524 DEBUG(D_transport) debug_printf("DANE: holding %s for later\n", a->domain);
3526 a->transport_return = DANE;
3531 /* If there is a filter command specified for this transport, we can now
3532 set it up. This cannot be done until the identity of the host is known. */
3534 if (tblock->filter_command)
3536 transport_filter_timeout = tblock->filter_timeout;
3538 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3541 if (!transport_set_up_command(&transport_filter_argv,
3542 tblock->filter_command, TRUE, DEFER, addrlist,
3543 string_sprintf("%.50s transport", tblock->name), NULL))
3545 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3546 FALSE, &sx->delivery_start);
3551 if ( transport_filter_argv
3552 && *transport_filter_argv
3553 && **transport_filter_argv
3554 && sx->peer_offered & OPTION_CHUNKING
3555 #ifndef DISABLE_DKIM
3556 /* When dkim signing, chunking is handled even with a transport-filter */
3557 && !(ob->dkim.dkim_private_key && ob->dkim.dkim_domain && ob->dkim.dkim_selector)
3558 && !ob->dkim.force_bodyhash
3562 sx->peer_offered &= ~OPTION_CHUNKING;
3563 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3567 /* For messages that have more than the maximum number of envelope recipients,
3568 we want to send several transactions down the same SMTP connection. (See
3569 comments in deliver.c as to how this reconciles, heuristically, with
3570 remote_max_parallel.) This optimization was added to Exim after the following
3571 code was already working. The simplest way to put it in without disturbing the
3572 code was to use a goto to jump back to this point when there is another
3573 transaction to handle. */
3576 sx->from_addr = return_path;
3577 sx->sync_addr = sx->first_addr;
3579 sx->send_rset = TRUE;
3580 sx->completed_addr = FALSE;
3583 /* If we are a continued-connection-after-verify the MAIL and RCPT
3584 commands were already sent; do not re-send but do mark the addrs as
3585 having been accepted up to RCPT stage. A traditional cont-conn
3586 always has a sequence number greater than one. */
3588 if (continue_hostname && continue_sequence == 1)
3590 /* sx->pending_MAIL = FALSE; */
3592 /* sx->next_addr = NULL; */
3594 for (address_item * addr = addrlist; addr; addr = addr->next)
3595 addr->transport_return = PENDING_OK;
3599 /* Initiate a message transfer. */
3601 switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))
3604 case -1: case -2: goto RESPONSE_FAILED;
3605 case -3: goto END_OFF;
3606 case -4: goto SEND_QUIT;
3607 default: goto SEND_FAILED;
3610 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3611 permanently or temporarily. We should have flushed and synced after the last
3619 for (a = sx->first_addr, cnt = 0; a && cnt < sx->max_rcpt; a = a->next, cnt++)
3620 if (a->transport_return != PENDING_OK)
3622 /*XXX could we find a better errno than 0 here? */
3623 set_errno_nohost(addrlist, 0, a->message, FAIL,
3624 testflag(a, af_pass_message), &sx->delivery_start);
3631 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3632 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3633 have a good recipient buffered up if we are pipelining. We don't want to waste
3634 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3635 are pipelining. The responses are all handled by sync_responses().
3636 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3639 if ( !(sx->peer_offered & OPTION_CHUNKING)
3640 && (sx->ok || (pipelining_active && !mua_wrapper)))
3642 int count = smtp_write_command(sx, SCMD_FLUSH, "DATA\r\n");
3644 if (count < 0) goto SEND_FAILED;
3645 switch(sync_responses(sx, count, sx->ok ? +1 : -1))
3647 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3648 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3651 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3652 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
3653 case 0: break; /* No 2xx or 5xx, but no probs */
3655 case -1: goto END_OFF; /* Timeout on RCPT */
3657 #ifndef DISABLE_PIPE_CONNECT
3658 case -5: /* TLS first-read error */
3659 case -4: HDEBUG(D_transport)
3660 debug_printf("failed reaping pipelined cmd responses\n");
3662 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3664 pipelining_active = FALSE;
3665 data_command = string_copy(big_buffer); /* Save for later error message */
3668 /* If there were no good recipients (but otherwise there have been no
3669 problems), just set ok TRUE, since we have handled address-specific errors
3670 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3671 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3672 well as body. Set the appropriate timeout value to be used for each chunk.
3673 (Haven't been able to make it work using select() for writing yet.) */
3676 && (!(sx->peer_offered & OPTION_CHUNKING) || !pipelining_active))
3678 /* Save the first address of the next batch. */
3679 sx->first_addr = sx->next_addr;
3685 transport_ctx tctx = {
3686 .u = {.fd = sx->cctx.sock}, /*XXX will this need TLS info? */
3689 .check_string = US".",
3690 .escape_string = US"..", /* Escaping strings */
3692 topt_use_crlf | topt_escape_headers
3693 | (tblock->body_only ? topt_no_headers : 0)
3694 | (tblock->headers_only ? topt_no_body : 0)
3695 | (tblock->return_path_add ? topt_add_return_path : 0)
3696 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3697 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3700 /* If using CHUNKING we need a callback from the generic transport
3701 support to us, for the sending of BDAT smtp commands and the reaping
3702 of responses. The callback needs a whole bunch of state so set up
3703 a transport-context structure to be passed around. */
3705 if (sx->peer_offered & OPTION_CHUNKING)
3707 tctx.check_string = tctx.escape_string = NULL;
3708 tctx.options |= topt_use_bdat;
3709 tctx.chunk_cb = smtp_chunk_cmd_callback;
3710 sx->pending_BDAT = FALSE;
3711 sx->good_RCPT = sx->ok;
3713 tctx.smtp_context = sx;
3716 tctx.options |= topt_end_dot;
3718 /* Save the first address of the next batch. */
3719 sx->first_addr = sx->next_addr;
3721 /* Responses from CHUNKING commands go in buffer. Otherwise,
3722 there has not been a response. */
3726 sigalrm_seen = FALSE;
3727 transport_write_timeout = ob->data_timeout;
3728 smtp_command = US"sending data block"; /* For error messages */
3729 DEBUG(D_transport|D_v)
3730 if (sx->peer_offered & OPTION_CHUNKING)
3731 debug_printf(" will write message using CHUNKING\n");
3733 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3734 transport_count = 0;
3736 #ifndef DISABLE_DKIM
3738 # ifdef MEASURE_TIMING
3740 gettimeofday(&t0, NULL);
3742 dkim_exim_sign_init();
3743 # ifdef EXPERIMENTAL_ARC
3745 uschar * s = ob->arc_sign;
3748 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
3750 if (!f.expand_string_forcedfail)
3752 message = US"failed to expand arc_sign";
3759 /* Ask dkim code to hash the body for ARC */
3760 (void) arc_ams_setup_sign_bodyhash();
3761 ob->dkim.force_bodyhash = TRUE;
3766 # ifdef MEASURE_TIMING
3767 report_time_since(&t0, US"dkim_exim_sign_init (delta)");
3770 sx->ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
3772 sx->ok = transport_write_message(&tctx, 0);
3775 /* transport_write_message() uses write() because it is called from other
3776 places to write to non-sockets. This means that under some OS (e.g. Solaris)
3777 it can exit with "Broken pipe" as its error. This really means that the
3778 socket got closed at the far end. */
3780 transport_write_timeout = 0; /* for subsequent transports */
3782 /* Failure can either be some kind of I/O disaster (including timeout),
3783 or the failure of a transport filter or the expansion of added headers.
3784 Or, when CHUNKING, it can be a protocol-detected failure. */
3787 if (message) goto SEND_FAILED;
3788 else goto RESPONSE_FAILED;
3790 /* We used to send the terminating "." explicitly here, but because of
3791 buffering effects at both ends of TCP/IP connections, you don't gain
3792 anything by keeping it separate, so it might as well go in the final
3793 data buffer for efficiency. This is now done by setting the topt_end_dot
3796 smtp_command = US"end of data";
3798 if (sx->peer_offered & OPTION_CHUNKING && sx->cmd_count > 1)
3800 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
3801 switch(sync_responses(sx, sx->cmd_count-1, 0))
3803 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3804 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3807 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3808 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
3809 case 0: break; /* No 2xx or 5xx, but no probs */
3811 case -1: goto END_OFF; /* Timeout on RCPT */
3813 #ifndef DISABLE_PIPE_CONNECT
3814 case -5: /* TLS first-read error */
3815 case -4: HDEBUG(D_transport)
3816 debug_printf("failed reaping pipelined cmd responses\n");
3818 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3822 #ifndef DISABLE_PRDR
3823 /* For PRDR we optionally get a partial-responses warning followed by the
3824 individual responses, before going on with the overall response. If we don't
3825 get the warning then deal with per non-PRDR. */
3829 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '3', ob->final_timeout);
3830 if (!sx->ok && errno == 0) switch(sx->buffer[0])
3832 case '2': sx->prdr_active = FALSE;
3835 case '4': errno = ERRNO_DATA4XX;
3836 addrlist->more_errno |=
3837 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3844 /* For non-PRDR SMTP, we now read a single response that applies to the
3845 whole message. If it is OK, then all the addresses have been delivered. */
3849 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3851 if (!sx->ok && errno == 0 && sx->buffer[0] == '4')
3853 errno = ERRNO_DATA4XX;
3854 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3858 /* For LMTP, we get back a response for every RCPT command that we sent;
3859 some may be accepted and some rejected. For those that get a response, their
3860 status is fixed; any that are accepted have been handed over, even if later
3861 responses crash - at least, that's how I read RFC 2033.
3863 If all went well, mark the recipient addresses as completed, record which
3864 host/IPaddress they were delivered to, and cut out RSET when sending another
3865 message down the same channel. Write the completed addresses to the journal
3866 now so that they are recorded in case there is a crash of hardware or
3867 software before the spool gets updated. Also record the final SMTP
3868 confirmation if needed (for SMTP only). */
3873 struct timeval delivery_time;
3875 uschar * conf = NULL;
3877 timesince(&delivery_time, &sx->delivery_start);
3878 sx->send_rset = FALSE;
3879 pipelining_active = FALSE;
3881 /* Set up confirmation if needed - applies only to SMTP */
3884 #ifdef DISABLE_EVENT
3885 LOGGING(smtp_confirmation) &&
3890 const uschar * s = string_printing(sx->buffer);
3891 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3892 conf = s == sx->buffer ? US string_copy(s) : US s;
3895 /* Process all transported addresses - for LMTP or PRDR, read a status for
3896 each one. We used to drop out at first_addr, until someone returned a 452
3897 followed by a 250... and we screwed up the accepted addresses. */
3899 for (address_item * addr = addrlist; addr; addr = addr->next)
3901 if (addr->transport_return != PENDING_OK) continue;
3903 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3904 remaining addresses. Otherwise, it's a return code for just the one
3905 address. For temporary errors, add a retry item for the address so that
3906 it doesn't get tried again too soon. */
3908 #ifndef DISABLE_PRDR
3909 if (sx->lmtp || sx->prdr_active)
3914 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3917 if (errno != 0 || sx->buffer[0] == 0) goto RESPONSE_FAILED;
3918 addr->message = string_sprintf(
3919 #ifndef DISABLE_PRDR
3920 "%s error after %s: %s", sx->prdr_active ? "PRDR":"LMTP",
3922 "LMTP error after %s: %s",
3924 data_command, string_printing(sx->buffer));
3925 setflag(addr, af_pass_message); /* Allow message to go to user */
3926 if (sx->buffer[0] == '5')
3927 addr->transport_return = FAIL;
3930 errno = ERRNO_DATA4XX;
3931 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3932 addr->transport_return = DEFER;
3933 #ifndef DISABLE_PRDR
3934 if (!sx->prdr_active)
3936 retry_add_item(addr, addr->address_retry_key, 0);
3940 sx->completed_addr = TRUE; /* NOW we can set this flag */
3941 if (LOGGING(smtp_confirmation))
3943 const uschar *s = string_printing(sx->buffer);
3944 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3945 conf = (s == sx->buffer) ? US string_copy(s) : US s;
3949 /* SMTP, or success return from LMTP for this address. Pass back the
3950 actual host that was used. */
3952 addr->transport_return = OK;
3953 addr->host_used = host;
3954 addr->delivery_time = delivery_time;
3955 addr->special_action = flag;
3956 addr->message = conf;
3958 if (tcp_out_fastopen)
3960 setflag(addr, af_tcp_fastopen_conn);
3961 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
3962 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
3964 if (sx->pipelining_used) setflag(addr, af_pipelining);
3965 #ifndef DISABLE_PIPE_CONNECT
3966 if (sx->early_pipe_active) setflag(addr, af_early_pipe);
3968 #ifndef DISABLE_PRDR
3969 if (sx->prdr_active) setflag(addr, af_prdr_used);
3971 if (sx->peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
3974 #ifndef DISABLE_PRDR
3975 if (!sx->prdr_active)
3978 /* Update the journal. For homonymic addresses, use the base address plus
3979 the transport name. See lots of comments in deliver.c about the reasons
3980 for the complications when homonyms are involved. Just carry on after
3981 write error, as it may prove possible to update the spool file later. */
3983 if (testflag(addr, af_homonym))
3984 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3986 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
3988 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx->buffer);
3989 len = Ustrlen(CS sx->buffer);
3990 if (write(journal_fd, sx->buffer, len) != len)
3991 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3992 "%s: %s", sx->buffer, strerror(errno));
3996 #ifndef DISABLE_PRDR
3997 if (sx->prdr_active)
3999 const uschar * overall_message;
4001 /* PRDR - get the final, overall response. For any non-success
4002 upgrade all the address statuses. */
4004 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4008 if(errno == 0 && sx->buffer[0] == '4')
4010 errno = ERRNO_DATA4XX;
4011 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4013 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4014 if (sx->buffer[0] == '5' || addr->transport_return == OK)
4015 addr->transport_return = PENDING_OK; /* allow set_errno action */
4016 goto RESPONSE_FAILED;
4019 /* Append the overall response to the individual PRDR response for logging
4020 and update the journal, or setup retry. */
4022 overall_message = string_printing(sx->buffer);
4023 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4024 if (addr->transport_return == OK)
4025 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
4027 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4028 if (addr->transport_return == OK)
4030 if (testflag(addr, af_homonym))
4031 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4033 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4035 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx->buffer);
4036 len = Ustrlen(CS sx->buffer);
4037 if (write(journal_fd, sx->buffer, len) != len)
4038 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4039 "%s: %s", sx->buffer, strerror(errno));
4041 else if (addr->transport_return == DEFER)
4042 retry_add_item(addr, addr->address_retry_key, -2);
4046 /* Ensure the journal file is pushed out to disk. */
4048 if (EXIMfsync(journal_fd) < 0)
4049 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
4055 /* Handle general (not specific to one address) failures here. The value of ok
4056 is used to skip over this code on the falling through case. A timeout causes a
4057 deferral. Other errors may defer or fail according to the response code, and
4058 may set up a special errno value, e.g. after connection chopped, which is
4059 assumed if errno == 0 and there is no text in the buffer. If control reaches
4060 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
4061 the problem is not related to this specific message. */
4066 uschar * set_message;
4072 sx->send_quit = check_response(host, &save_errno, addrlist->more_errno,
4073 sx->buffer, &code, &message, &pass_message);
4081 message = string_sprintf("send() to %s [%s] failed: %s",
4082 host->name, host->address, message ? message : US strerror(save_errno));
4083 sx->send_quit = FALSE;
4091 sx->ok = FALSE; /* For when reached by GOTO */
4092 set_message = message;
4094 /* We want to handle timeouts after MAIL or "." and loss of connection after
4095 "." specially. They can indicate a problem with the sender address or with
4096 the contents of the message rather than a real error on the connection. These
4097 cases are treated in the same way as a 4xx response. This next bit of code
4098 does the classification. */
4105 message_error = TRUE;
4109 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4110 Ustrncmp(smtp_command,"end ",4) == 0;
4113 case ERRNO_SMTPCLOSED:
4114 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4118 message_error = FALSE;
4122 /* Handle the cases that are treated as message errors. These are:
4124 (a) negative response or timeout after MAIL
4125 (b) negative response after DATA
4126 (c) negative response or timeout or dropped connection after "."
4127 (d) utf8 support required and not offered
4129 It won't be a negative response or timeout after RCPT, as that is dealt
4130 with separately above. The action in all cases is to set an appropriate
4131 error code for all the addresses, but to leave yield set to OK because the
4132 host itself has not failed. Of course, it might in practice have failed
4133 when we've had a timeout, but if so, we'll discover that at the next
4134 delivery attempt. For a temporary error, set the message_defer flag, and
4135 write to the logs for information if this is not the last host. The error
4136 for the last host will be logged as part of the address's log line. */
4140 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4142 /* If there's an errno, the message contains just the identity of
4147 else /* Anything other than 5 is treated as temporary */
4151 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4153 write_logs(host, message, sx->first_addr ? sx->first_addr->basic_errno : 0);
4155 *message_defer = TRUE;
4158 DEBUG(D_transport) if (sx->cctx.sock >= 0)
4161 if (ioctl(sx->cctx.sock, TIOCOUTQ, &n) == 0)
4162 debug_printf("%d bytes remain in socket output buffer\n", n);
4166 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4167 ".", or some other transportation error. We defer all addresses and yield
4168 DEFER, except for the case of failed add_headers expansion, or a transport
4169 filter failure, when the yield should be ERROR, to stop it trying other
4174 #ifndef DISABLE_PIPE_CONNECT
4175 /* If we were early-pipelinng and the actual EHLO response did not match
4176 the cached value we assumed, we could have detected it and passed a
4177 custom errno through to here. It would be nice to RSET and retry right
4178 away, but to reliably do that we eould need an extra synch point before
4179 we committed to data and that would discard half the gained roundrips.
4180 Or we could summarily drop the TCP connection. but that is also ugly.
4181 Instead, we ignore the possibility (having freshened the cache) and rely
4182 on the server telling us with a nonmessage error if we have tried to
4183 do something it no longer supports. */
4186 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4187 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4191 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host,
4192 #ifdef EXPERIMENTAL_DSN_INFO
4193 sx->smtp_greeting, sx->helo_response,
4195 &sx->delivery_start);
4198 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4199 SMTP session tidily. However, if there were too many addresses to send in one
4200 message (indicated by first_addr being non-NULL) we want to carry on with the
4201 rest of them. Also, it is desirable to send more than one message down the SMTP
4202 connection if there are several waiting, provided we haven't already sent so
4203 many as to hit the configured limit. The function transport_check_waiting looks
4204 for a waiting message and returns its id. Then transport_pass_socket tries to
4205 set up a continued delivery by passing the socket on to another process. The
4206 variable send_rset is FALSE if a message has just been successfully transferred.
4208 If we are already sending down a continued channel, there may be further
4209 addresses not yet delivered that are aimed at the same host, but which have not
4210 been passed in this run of the transport. In this case, continue_more will be
4211 true, and all we should do is send RSET if necessary, and return, leaving the
4214 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4215 do not want to continue with other messages down the same channel, because that
4216 can lead to looping between two or more messages, all with the same,
4217 temporarily failing address(es). [The retry information isn't updated yet, so
4218 new processes keep on trying.] We probably also don't want to try more of this
4219 message's addresses either.
4221 If we have started a TLS session, we have to end it before passing the
4222 connection to a new process. However, not all servers can handle this (Exim
4223 can), so we do not pass such a connection on if the host matches
4224 hosts_nopass_tls. */
4227 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4228 "yield=%d first_address is %sNULL\n", sx->ok, sx->send_quit,
4229 sx->send_rset, f.continue_more, yield, sx->first_addr ? "not " : "");
4231 if (sx->completed_addr && sx->ok && sx->send_quit)
4233 smtp_compare_t t_compare;
4235 t_compare.tblock = tblock;
4236 t_compare.current_sender_address = sender_address;
4238 if ( sx->first_addr /* more addrs for this message */
4239 || f.continue_more /* more addrs for coninued-host */
4242 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4243 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4247 transport_check_waiting(tblock->name, host->name,
4248 tblock->connection_max_messages, new_message_id,
4249 (oicf)smtp_are_same_identities, (void*)&t_compare)
4256 if (! (sx->ok = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4258 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
4259 host->address, strerror(errno));
4260 sx->send_quit = FALSE;
4262 else if (! (sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4263 '2', ob->command_timeout)))
4266 sx->send_quit = check_response(host, &errno, 0, sx->buffer, &code, &msg,
4270 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4271 host->name, host->address, msg);
4275 /* Either RSET was not needed, or it succeeded */
4282 int socket_fd = sx->cctx.sock;
4285 if (sx->first_addr) /* More addresses still to be sent */
4286 { /* for this message */
4287 continue_sequence++; /* Causes * in logging */
4288 pipelining_active = sx->pipelining_used; /* was cleared at DATA */
4292 /* Unless caller said it already has more messages listed for this host,
4293 pass the connection on to a new Exim process (below, the call to
4294 transport_pass_socket). If the caller has more ready, just return with
4295 the connection still open. */
4298 if (tls_out.active.sock >= 0)
4299 if ( f.continue_more
4300 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4302 /* Before passing the socket on, or returning to caller with it still
4303 open, we must shut down TLS. Not all MTAs allow for the continuation
4304 of the SMTP session when TLS is shut down. We test for this by sending
4305 a new EHLO. If we don't get a good response, we don't attempt to pass
4308 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4309 sx->cctx.tls_ctx = NULL;
4310 tls_out.active.sock = -1;
4311 smtp_peer_options = smtp_peer_options_wrap;
4313 && smtp_write_command(sx, SCMD_FLUSH, "EHLO %s\r\n", sx->helo_data)
4315 && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4316 '2', ob->command_timeout);
4318 if (sx->ok && f.continue_more)
4319 goto TIDYUP; /* More addresses for another run */
4323 /* Set up a pipe for proxying TLS for the new transport process */
4325 smtp_peer_options |= OPTION_TLS;
4326 if ((sx->ok = socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4329 set_errno(sx->first_addr, errno, US"internal allocation problem",
4331 # ifdef EXPERIMENTAL_DSN_INFO
4332 sx->smtp_greeting, sx->helo_response,
4334 &sx->delivery_start);
4338 if (f.continue_more)
4339 goto TIDYUP; /* More addresses for another run */
4341 /* If the socket is successfully passed, we mustn't send QUIT (or
4342 indeed anything!) from here. */
4344 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4345 propagate it from the initial
4347 if (sx->ok && transport_pass_socket(tblock->name, host->name,
4348 host->address, new_message_id, socket_fd))
4350 sx->send_quit = FALSE;
4352 /* We have passed the client socket to a fresh transport process.
4353 If TLS is still active, we need to proxy it for the transport we
4354 just passed the baton to. Fork a child to to do it, and return to
4355 get logging done asap. Which way to place the work makes assumptions
4356 about post-fork prioritisation which may not hold on all platforms. */
4358 if (tls_out.active.sock >= 0)
4360 int pid = exim_fork(US"tls-proxy-interproc");
4361 if (pid == 0) /* child; fork again to disconnect totally */
4363 /* does not return */
4364 smtp_proxy_tls(sx->cctx.tls_ctx, sx->buffer, sizeof(sx->buffer), pfd,
4365 ob->command_timeout);
4368 if (pid > 0) /* parent */
4371 /* tidy the inter-proc to disconn the proxy proc */
4372 waitpid(pid, NULL, 0);
4373 tls_close(sx->cctx.tls_ctx, TLS_NO_SHUTDOWN);
4374 sx->cctx.tls_ctx = NULL;
4375 (void)close(sx->cctx.sock);
4377 continue_transport = NULL;
4378 continue_hostname = NULL;
4381 log_write(0, LOG_PANIC_DIE, "fork failed");
4387 /* If RSET failed and there are addresses left, they get deferred. */
4389 set_errno(sx->first_addr, errno, msg, DEFER, FALSE, host,
4390 #ifdef EXPERIMENTAL_DSN_INFO
4391 sx->smtp_greeting, sx->helo_response,
4393 &sx->delivery_start);
4397 /* End off tidily with QUIT unless the connection has died or the socket has
4398 been passed to another process. */
4402 /* Use _MORE to get QUIT in FIN segment */
4403 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4408 # ifdef EXIM_TCP_CORK
4409 if (sx->cctx.tls_ctx) /* Use _CORK to get TLS Close Notify in FIN segment */
4410 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4413 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
4414 sx->cctx.tls_ctx = NULL;
4417 /* Close the socket, and return the appropriate value, first setting
4418 works because the NULL setting is passed back to the calling process, and
4419 remote_max_parallel is forced to 1 when delivering over an existing connection,
4421 If all went well and continue_more is set, we shouldn't actually get here if
4422 there are further addresses, as the return above will be taken. However,
4423 writing RSET might have failed, or there may be other addresses whose hosts are
4424 specified in the transports, and therefore not visible at top level, in which
4425 case continue_more won't get set. */
4427 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4430 /* This flushes data queued in the socket, being the QUIT and any TLS Close,
4431 sending them along with the client FIN flag. Us (we hope) sending FIN first
4432 means we (client) take the TIME_WAIT state, so the server (which likely has a
4433 higher connection rate) does no have to. */
4435 shutdown(sx->cctx.sock, SHUT_WR);
4437 /* Wait for (we hope) ack of our QUIT, and a server FIN. Discard any data
4438 received, then discard the socket. Any packet received after then, or receive
4439 data still in the socket, will get a RST - hence the pause/drain. */
4442 testharness_pause_ms(200);
4443 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4444 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
4445 i--; /* drain socket */
4447 (void)close(sx->cctx.sock);
4449 #ifndef DISABLE_EVENT
4450 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
4456 sx->first_addr = NULL;
4457 for (address_item * a = sx->addrlist->next; a; a = a->next)
4458 if (a->transport_return == DANE)
4460 a->transport_return = PENDING_DEFER;
4461 if (!sx->first_addr)
4463 /* Remember the new start-point in the addrlist, for smtp_setup_conn()
4464 to get the domain string for SNI */
4467 DEBUG(D_transport) debug_printf("DANE: go-around for %s\n", a->domain);
4474 continue_transport = NULL;
4475 continue_hostname = NULL;
4480 if (dane_held) for (address_item * a = sx->addrlist->next; a; a = a->next)
4481 if (a->transport_return == DANE)
4482 a->transport_return = PENDING_DEFER;
4490 /*************************************************
4491 * Closedown entry point *
4492 *************************************************/
4494 /* This function is called when exim is passed an open smtp channel
4495 from another incarnation, but the message which it has been asked
4496 to deliver no longer exists. The channel is on stdin.
4498 We might do fancy things like looking for another message to send down
4499 the channel, but if the one we sought has gone, it has probably been
4500 delivered by some other process that itself will seek further messages,
4501 so just close down our connection.
4503 Argument: pointer to the transport instance block
4508 smtp_transport_closedown(transport_instance *tblock)
4510 smtp_transport_options_block * ob = SOB tblock->options_block;
4511 client_conn_ctx cctx;
4514 uschar inbuffer[4096];
4515 uschar outbuffer[16];
4517 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4518 cctx.sock = fileno(stdin);
4519 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4521 sx.inblock.cctx = &cctx;
4522 sx.inblock.buffer = inbuffer;
4523 sx.inblock.buffersize = sizeof(inbuffer);
4524 sx.inblock.ptr = inbuffer;
4525 sx.inblock.ptrend = inbuffer;
4527 sx.outblock.cctx = &cctx;
4528 sx.outblock.buffersize = sizeof(outbuffer);
4529 sx.outblock.buffer = outbuffer;
4530 sx.outblock.ptr = outbuffer;
4531 sx.outblock.cmd_count = 0;
4532 sx.outblock.authenticating = FALSE;
4534 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4535 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
4536 (void)close(cctx.sock);
4541 /*************************************************
4542 * Prepare addresses for delivery *
4543 *************************************************/
4545 /* This function is called to flush out error settings from previous delivery
4546 attempts to other hosts. It also records whether we got here via an MX record
4547 or not in the more_errno field of the address. We are interested only in
4548 addresses that are still marked DEFER - others may have got delivered to a
4549 previously considered IP address. Set their status to PENDING_DEFER to indicate
4550 which ones are relevant this time.
4553 addrlist the list of addresses
4554 host the host we are delivering to
4556 Returns: the first address for this delivery
4559 static address_item *
4560 prepare_addresses(address_item *addrlist, host_item *host)
4562 address_item *first_addr = NULL;
4563 for (address_item * addr = addrlist; addr; addr = addr->next)
4564 if (addr->transport_return == DEFER)
4566 if (!first_addr) first_addr = addr;
4567 addr->transport_return = PENDING_DEFER;
4568 addr->basic_errno = 0;
4569 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
4570 addr->message = NULL;
4572 addr->cipher = NULL;
4573 addr->ourcert = NULL;
4574 addr->peercert = NULL;
4575 addr->peerdn = NULL;
4576 addr->ocsp = OCSP_NOT_REQ;
4577 addr->tlsver = NULL;
4579 #ifdef EXPERIMENTAL_DSN_INFO
4580 addr->smtp_greeting = NULL;
4581 addr->helo_response = NULL;
4589 /*************************************************
4590 * Main entry point *
4591 *************************************************/
4593 /* See local README for interface details. As this is a remote transport, it is
4594 given a chain of addresses to be delivered in one connection, if possible. It
4595 always returns TRUE, indicating that each address has its own independent
4596 status set, except if there is a setting up problem, in which case it returns
4600 smtp_transport_entry(
4601 transport_instance *tblock, /* data for this instantiation */
4602 address_item *addrlist) /* addresses we are working on */
4605 int hosts_defer = 0;
4607 int hosts_looked_up = 0;
4608 int hosts_retry = 0;
4609 int hosts_serial = 0;
4610 int hosts_total = 0;
4611 int total_hosts_tried = 0;
4612 BOOL expired = TRUE;
4613 uschar *expanded_hosts = NULL;
4615 uschar *tid = string_sprintf("%s transport", tblock->name);
4616 smtp_transport_options_block *ob = SOB tblock->options_block;
4617 host_item *hostlist = addrlist->host_list;
4618 host_item *host = NULL;
4622 debug_printf("%s transport entered\n", tblock->name);
4623 for (address_item * addr = addrlist; addr; addr = addr->next)
4624 debug_printf(" %s\n", addr->address);
4627 debug_printf("hostlist:\n");
4628 for (host_item * host = hostlist; host; host = host->next)
4629 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
4631 if (continue_hostname)
4632 debug_printf("already connected to %s [%s] (on fd %d)\n",
4633 continue_hostname, continue_host_address,
4634 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
4637 /* Check the restrictions on line length */
4639 if (max_received_linelength > ob->message_linelength_limit)
4642 gettimeofday(&now, NULL);
4644 for (address_item * addr = addrlist; addr; addr = addr->next)
4645 if (addr->transport_return == DEFER)
4646 addr->transport_return = PENDING_DEFER;
4648 set_errno_nohost(addrlist, ERRNO_SMTPFORMAT,
4649 US"message has lines too long for transport", FAIL, TRUE, &now);
4653 /* Set the flag requesting that these hosts be added to the waiting
4654 database if the delivery fails temporarily or if we are running with
4655 queue_smtp or a 2-stage queue run. This gets unset for certain
4656 kinds of error, typically those that are specific to the message. */
4658 update_waiting = TRUE;
4660 /* If a host list is not defined for the addresses - they must all have the
4661 same one in order to be passed to a single transport - or if the transport has
4662 a host list with hosts_override set, use the host list supplied with the
4663 transport. It is an error for this not to exist. */
4665 if (!hostlist || (ob->hosts_override && ob->hosts))
4669 addrlist->message = string_sprintf("%s transport called with no hosts set",
4671 addrlist->transport_return = PANIC;
4672 return FALSE; /* Only top address has status */
4675 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
4678 /* If the transport's host list contains no '$' characters, and we are not
4679 randomizing, it is fixed and therefore a chain of hosts can be built once
4680 and for all, and remembered for subsequent use by other calls to this
4681 transport. If, on the other hand, the host list does contain '$', or we are
4682 randomizing its order, we have to rebuild it each time. In the fixed case,
4683 as the hosts string will never be used again, it doesn't matter that we
4684 replace all the : characters with zeros. */
4688 uschar *s = ob->hosts;
4690 if (Ustrchr(s, '$'))
4692 if (!(expanded_hosts = expand_string(s)))
4694 addrlist->message = string_sprintf("failed to expand list of hosts "
4695 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
4696 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
4697 return FALSE; /* Only top address has status */
4699 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
4700 "\"%s\"\n", s, expanded_hosts);
4704 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
4708 log_write(0, LOG_MAIN|LOG_PANIC,
4709 "attempt to use tainted host list '%s' from '%s' in transport %s",
4710 s, ob->hosts, tblock->name);
4711 /* Avoid leaking info to an attacker */
4712 addrlist->message = US"internal configuration error";
4713 addrlist->transport_return = PANIC;
4717 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
4719 /* Check that the expansion yielded something useful. */
4723 string_sprintf("%s transport has empty hosts setting", tblock->name);
4724 addrlist->transport_return = PANIC;
4725 return FALSE; /* Only top address has status */
4728 /* If there was no expansion of hosts, save the host list for
4731 if (!expanded_hosts) ob->hostlist = hostlist;
4734 /* This is not the first time this transport has been run in this delivery;
4735 the host list was built previously. */
4738 hostlist = ob->hostlist;
4741 /* The host list was supplied with the address. If hosts_randomize is set, we
4742 must sort it into a random order if it did not come from MX records and has not
4743 already been randomized (but don't bother if continuing down an existing
4746 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
4748 host_item *newlist = NULL;
4751 host_item *h = hostlist;
4752 hostlist = hostlist->next;
4754 h->sort_key = random_number(100);
4761 else if (h->sort_key < newlist->sort_key)
4768 host_item *hh = newlist;
4771 if (h->sort_key < hh->next->sort_key) break;
4779 hostlist = addrlist->host_list = newlist;
4782 /* Sort out the default port. */
4784 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
4786 /* For each host-plus-IP-address on the list:
4788 . If this is a continued delivery and the host isn't the one with the
4789 current connection, skip.
4791 . If the status is unusable (i.e. previously failed or retry checked), skip.
4793 . If no IP address set, get the address, either by turning the name into
4794 an address, calling gethostbyname if gethostbyname is on, or by calling
4795 the DNS. The DNS may yield multiple addresses, in which case insert the
4796 extra ones into the list.
4798 . Get the retry data if not previously obtained for this address and set the
4799 field which remembers the state of this address. Skip if the retry time is
4800 not reached. If not, remember whether retry data was found. The retry string
4801 contains both the name and the IP address.
4803 . Scan the list of addresses and mark those whose status is DEFER as
4804 PENDING_DEFER. These are the only ones that will be processed in this cycle
4807 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
4808 Some addresses may be successfully delivered, others may fail, and yet
4809 others may get temporary errors and so get marked DEFER.
4811 . The return from the delivery attempt is OK if a connection was made and a
4812 valid SMTP dialogue was completed. Otherwise it is DEFER.
4814 . If OK, add a "remove" retry item for this host/IPaddress, if any.
4816 . If fail to connect, or other defer state, add a retry item.
4818 . If there are any addresses whose status is still DEFER, carry on to the
4819 next host/IPaddress, unless we have tried the number of hosts given
4820 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
4821 there is some fancy logic for hosts_max_try that means its limit can be
4822 overstepped in some circumstances.
4824 If we get to the end of the list, all hosts have deferred at least one address,
4825 or not reached their retry times. If delay_after_cutoff is unset, it requests a
4826 delivery attempt to those hosts whose last try was before the arrival time of
4827 the current message. To cope with this, we have to go round the loop a second
4828 time. After that, set the status and error data for any addresses that haven't
4829 had it set already. */
4831 for (int cutoff_retry = 0;
4832 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
4835 host_item *nexthost = NULL;
4836 int unexpired_hosts_tried = 0;
4837 BOOL continue_host_tried = FALSE;
4839 retry_non_continued:
4840 for (host = hostlist;
4842 && unexpired_hosts_tried < ob->hosts_max_try
4843 && total_hosts_tried < ob->hosts_max_try_hardlimit;
4848 BOOL host_is_expired = FALSE;
4849 BOOL message_defer = FALSE;
4850 BOOL some_deferred = FALSE;
4851 address_item *first_addr = NULL;
4852 uschar *interface = NULL;
4853 uschar *retry_host_key = NULL;
4854 uschar *retry_message_key = NULL;
4855 uschar *serialize_key = NULL;
4857 /* Default next host is next host. :-) But this can vary if the
4858 hosts_max_try limit is hit (see below). It may also be reset if a host
4859 address is looked up here (in case the host was multihomed). */
4861 nexthost = host->next;
4863 /* If the address hasn't yet been obtained from the host name, look it up
4864 now, unless the host is already marked as unusable. If it is marked as
4865 unusable, it means that the router was unable to find its IP address (in
4866 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
4867 the lookup failed last time. We don't get this far if *all* MX records
4868 point to non-existent hosts; that is treated as a hard error.
4870 We can just skip this host entirely. When the hosts came from the router,
4871 the address will timeout based on the other host(s); when the address is
4872 looked up below, there is an explicit retry record added.
4874 Note that we mustn't skip unusable hosts if the address is not unset; they
4875 may be needed as expired hosts on the 2nd time round the cutoff loop. */
4879 int new_port, flags;
4881 if (host->status >= hstatus_unusable)
4883 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
4888 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
4890 /* The host name is permitted to have an attached port. Find it, and
4891 strip it from the name. Just remember it for now. */
4893 new_port = host_item_get_port(host);
4895 /* Count hosts looked up */
4899 /* Find by name if so configured, or if it's an IP address. We don't
4900 just copy the IP address, because we need the test-for-local to happen. */
4902 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
4903 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
4904 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
4906 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
4907 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
4909 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
4910 &ob->dnssec, /* domains for request/require */
4913 /* Update the host (and any additional blocks, resulting from
4914 multihoming) with a host-specific port, if any. */
4916 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
4918 /* Failure to find the host at this time (usually DNS temporary failure)
4919 is really a kind of routing failure rather than a transport failure.
4920 Therefore we add a retry item of the routing kind, not to stop us trying
4921 to look this name up here again, but to ensure the address gets timed
4922 out if the failures go on long enough. A complete failure at this point
4923 commonly points to a configuration error, but the best action is still
4924 to carry on for the next host. */
4926 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
4928 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
4930 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
4931 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
4932 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
4933 host->status = hstatus_unusable;
4935 for (address_item * addr = addrlist; addr; addr = addr->next)
4937 if (addr->transport_return != DEFER) continue;
4938 addr->basic_errno = ERRNO_UNKNOWNHOST;
4939 addr->message = string_sprintf(
4940 rc == HOST_FIND_SECURITY
4941 ? "lookup of IP address for %s was insecure"
4942 : "failed to lookup IP address for %s",
4948 /* If the host is actually the local host, we may have a problem, or
4949 there may be some cunning configuration going on. In the problem case,
4950 log things and give up. The default transport status is already DEFER. */
4952 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
4954 for (address_item * addr = addrlist; addr; addr = addr->next)
4956 addr->basic_errno = ERRNO_HOST_IS_LOCAL;
4957 addr->message = string_sprintf("%s transport found host %s to be "
4958 "local", tblock->name, host->name);
4962 } /* End of block for IP address lookup */
4964 /* If this is a continued delivery, we are interested only in the host
4965 which matches the name of the existing open channel. The check is put
4966 here after the local host lookup, in case the name gets expanded as a
4967 result of the lookup. Set expired FALSE, to save the outer loop executing
4970 if (continue_hostname)
4971 if ( Ustrcmp(continue_hostname, host->name) != 0
4972 || Ustrcmp(continue_host_address, host->address) != 0
4976 continue; /* With next host */
4979 continue_host_tried = TRUE;
4981 /* Reset the default next host in case a multihomed host whose addresses
4982 are not looked up till just above added to the host list. */
4984 nexthost = host->next;
4986 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
4987 domain is in queue_smtp_domains, we don't actually want to attempt any
4988 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
4989 there is a lookup defer in queue_smtp_domains, proceed as if the domain
4990 were not in it. We don't want to hold up all SMTP deliveries! Except when
4991 doing a two-stage queue run, don't do this if forcing. */
4993 if ( (!f.deliver_force || f.queue_2stage)
4995 || match_isinlist(addrlist->domain,
4996 CUSS &queue_smtp_domains, 0,
4997 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK)
5000 DEBUG(D_transport) debug_printf("first-pass routing only\n");
5002 for (address_item * addr = addrlist; addr; addr = addr->next)
5003 if (addr->transport_return == DEFER)
5004 addr->message = US"first-pass only routing due to -odqs, "
5005 "queue_smtp_domains or control=queue";
5006 continue; /* With next host */
5009 /* Count hosts being considered - purely for an intelligent comment
5010 if none are usable. */
5014 /* Set $host and $host address now in case they are needed for the
5015 interface expansion or the serialize_hosts check; they remain set if an
5016 actual delivery happens. */
5018 deliver_host = host->name;
5019 deliver_host_address = host->address;
5020 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
5021 : host->dnssec == DS_NO ? US"no"
5024 /* Set up a string for adding to the retry key if the port number is not
5025 the standard SMTP port. A host may have its own port setting that overrides
5028 pistring = string_sprintf(":%d", host->port == PORT_NONE
5029 ? defport : host->port);
5030 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
5032 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
5033 string is set, even if constant (as different transports can have different
5034 constant settings), we must add it to the key that is used for retries,
5035 because connections to the same host from a different interface should be
5036 treated separately. */
5038 host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
5040 uschar * s = ob->interface;
5043 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
5045 pistring = string_sprintf("%s/%s", pistring, interface);
5049 /* The first time round the outer loop, check the status of the host by
5050 inspecting the retry data. The second time round, we are interested only
5051 in expired hosts that haven't been tried since this message arrived. */
5053 if (cutoff_retry == 0)
5056 /* Ensure the status of the address is set by checking retry data if
5057 necessary. There may be host-specific retry data (applicable to all
5058 messages) and also data for retries of a specific message at this host.
5059 If either of these retry records are actually read, the keys used are
5060 returned to save recomputing them later. */
5062 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5063 US"retry_include_ip_address", ob->retry_include_ip_address,
5064 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5065 continue; /* with next host */
5067 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
5068 incl_ip, &retry_host_key, &retry_message_key);
5070 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
5071 host->address ? host->address : US"", pistring,
5072 host->status == hstatus_usable ? "usable"
5073 : host->status == hstatus_unusable ? "unusable"
5074 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
5076 /* Skip this address if not usable at this time, noting if it wasn't
5077 actually expired, both locally and in the address. */
5079 switch (host->status)
5081 case hstatus_unusable:
5083 setflag(addrlist, af_retry_skipped);
5086 case hstatus_unusable_expired:
5089 case hwhy_retry: hosts_retry++; break;
5090 case hwhy_failed: hosts_fail++; break;
5092 case hwhy_deferred: hosts_defer++; break;
5095 /* If there was a retry message key, implying that previously there
5096 was a message-specific defer, we don't want to update the list of
5097 messages waiting for these hosts. */
5099 if (retry_message_key) update_waiting = FALSE;
5100 continue; /* With the next host or IP address */
5104 /* Second time round the loop: if the address is set but expired, and
5105 the message is newer than the last try, let it through. */
5110 || host->status != hstatus_unusable_expired
5111 || host->last_try > received_time.tv_sec)
5113 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
5114 host->name, host->address, pistring);
5115 host_is_expired = TRUE;
5118 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
5119 it remains TRUE only if all hosts are expired and none are actually tried.
5124 /* If this host is listed as one to which access must be serialized,
5125 see if another Exim process has a connection to it, and if so, skip
5126 this host. If not, update the database to record our connection to it
5127 and remember this for later deletion. Do not do any of this if we are
5128 sending the message down a pre-existing connection. */
5130 if ( !continue_hostname
5131 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
5133 serialize_key = string_sprintf("host-serialize-%s", host->name);
5134 if (!enq_start(serialize_key, 1))
5137 debug_printf("skipping host %s because another Exim process "
5138 "is connected to it\n", host->name);
5144 /* OK, we have an IP address that is not waiting for its retry time to
5145 arrive (it might be expired) OR (second time round the loop) we have an
5146 expired host that hasn't been tried since the message arrived. Have a go
5147 at delivering the message to it. First prepare the addresses by flushing
5148 out the result of previous attempts, and finding the first address that
5149 is still to be delivered. */
5151 first_addr = prepare_addresses(addrlist, host);
5153 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5154 message_id, host->name, host->address, addrlist->address,
5155 addrlist->next ? ", ..." : "");
5157 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5158 message_id, host->name, host->address, pistring, addrlist->address,
5159 addrlist->next ? ", ..." : "");
5161 /* This is not for real; don't do the delivery. If there are
5162 any remaining hosts, list them. */
5167 gettimeofday(&now, NULL);
5168 set_errno_nohost(addrlist, 0, NULL, OK, FALSE, &now);
5169 for (address_item * addr = addrlist; addr; addr = addr->next)
5171 addr->host_used = host;
5172 addr->special_action = '*';
5173 addr->message = US"delivery bypassed by -N option";
5177 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5178 "*** host and remaining hosts:\n", tblock->name);
5179 for (host_item * host2 = host; host2; host2 = host2->next)
5180 debug_printf(" %s [%s]\n", host2->name,
5181 host2->address ? host2->address : US"unset");
5186 /* This is for real. If the host is expired, we don't count it for
5187 hosts_max_retry. This ensures that all hosts must expire before an address
5188 is timed out, unless hosts_max_try_hardlimit (which protects against
5189 lunatic DNS configurations) is reached.
5191 If the host is not expired and we are about to hit the hosts_max_retry
5192 limit, check to see if there is a subsequent hosts with a different MX
5193 value. If so, make that the next host, and don't count this one. This is a
5194 heuristic to make sure that different MXs do get tried. With a normal kind
5195 of retry rule, they would get tried anyway when the earlier hosts were
5196 delayed, but if the domain has a "retry every time" type of rule - as is
5197 often used for the the very large ISPs, that won't happen. */
5202 /* Make a copy of the host if it is local to this invocation
5203 of the transport. */
5207 thost = store_get(sizeof(host_item), FALSE);
5209 thost->name = string_copy(host->name);
5210 thost->address = string_copy(host->address);
5215 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5218 debug_printf("hosts_max_try limit reached with this host\n");
5219 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5222 unexpired_hosts_tried--;
5223 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5224 "and will be tried\n");
5229 /* Attempt the delivery. */
5231 total_hosts_tried++;
5232 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5233 &message_defer, FALSE);
5236 OK => connection made, each address contains its result;
5237 message_defer is set for message-specific defers (when all
5238 recipients are marked defer)
5239 DEFER => there was a non-message-specific delivery problem;
5240 ERROR => there was a problem setting up the arguments for a filter,
5241 or there was a problem with expanding added headers
5244 /* If the result is not OK, there was a non-message-specific problem.
5245 If the result is DEFER, we need to write to the logs saying what happened
5246 for this particular host, except in the case of authentication and TLS
5247 failures, where the log has already been written. If all hosts defer a
5248 general message is written at the end. */
5250 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5251 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5252 write_logs(host, first_addr->message, first_addr->basic_errno);
5254 #ifndef DISABLE_EVENT
5256 deferred_event_raise(first_addr, host, US"msg:host:defer");
5259 /* If STARTTLS was accepted, but there was a failure in setting up the
5260 TLS session (usually a certificate screwup), and the host is not in
5261 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5262 TLS forcibly turned off. We have to start from scratch with a new SMTP
5263 connection. That's why the retry is done from here, not from within
5264 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5265 session, so the in-clear transmission after those errors, if permitted,
5266 happens inside smtp_deliver().] */
5270 && first_addr->basic_errno == ERRNO_TLSFAILURE
5271 && ob->tls_tempfail_tryclear
5272 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5275 log_write(0, LOG_MAIN,
5276 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5277 first_addr->message, host->name, host->address);
5278 first_addr = prepare_addresses(addrlist, host);
5279 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5280 &message_defer, TRUE);
5281 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5282 write_logs(host, first_addr->message, first_addr->basic_errno);
5283 # ifndef DISABLE_EVENT
5285 deferred_event_raise(first_addr, host, US"msg:host:defer");
5288 #endif /*DISABLE_TLS*/
5290 #ifndef DISABLE_EVENT
5291 /* If the last host gave a defer raise a per-message event */
5294 && unexpired_hosts_tried < ob->hosts_max_try
5295 && total_hosts_tried < ob->hosts_max_try_hardlimit
5297 && (message_defer || rc == DEFER)
5299 deferred_event_raise(first_addr, host, US"msg:defer");
5303 /* Delivery attempt finished */
5305 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5306 message_id, host->name, host->address, pistring, addrlist->address,
5307 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5309 /* Release serialization if set up */
5311 if (serialize_key) enq_end(serialize_key);
5313 /* If the result is DEFER, or if a host retry record is known to exist, we
5314 need to add an item to the retry chain for updating the retry database
5315 at the end of delivery. We only need to add the item to the top address,
5316 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5317 for any other delivery attempts using the same address. (It is copied into
5318 the unusable tree at the outer level, so even if different address blocks
5319 contain the same address, it still won't get tried again.) */
5321 if (rc == DEFER || retry_host_key)
5323 int delete_flag = rc != DEFER ? rf_delete : 0;
5324 if (!retry_host_key)
5327 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5328 US"retry_include_ip_address", ob->retry_include_ip_address,
5329 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5330 incl_ip = TRUE; /* error; use most-specific retry record */
5332 retry_host_key = incl_ip
5333 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5334 : string_sprintf("T:%S%s", host->name, pistring);
5337 /* If a delivery of another message over an existing SMTP connection
5338 yields DEFER, we do NOT set up retry data for the host. This covers the
5339 case when there are delays in routing the addresses in the second message
5340 that are so long that the server times out. This is alleviated by not
5341 routing addresses that previously had routing defers when handling an
5342 existing connection, but even so, this case may occur (e.g. if a
5343 previously happily routed address starts giving routing defers). If the
5344 host is genuinely down, another non-continued message delivery will
5345 notice it soon enough. */
5347 if (delete_flag != 0 || !continue_hostname)
5348 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5350 /* We may have tried an expired host, if its retry time has come; ensure
5351 the status reflects the expiry for the benefit of any other addresses. */
5355 host->status = host_is_expired
5356 ? hstatus_unusable_expired : hstatus_unusable;
5357 host->why = hwhy_deferred;
5361 /* If message_defer is set (host was OK, but every recipient got deferred
5362 because of some message-specific problem), or if that had happened
5363 previously so that a message retry key exists, add an appropriate item
5364 to the retry chain. Note that if there was a message defer but now there is
5365 a host defer, the message defer record gets deleted. That seems perfectly
5366 reasonable. Also, stop the message from being remembered as waiting
5367 for specific hosts. */
5369 if (message_defer || retry_message_key)
5371 int delete_flag = message_defer ? 0 : rf_delete;
5372 if (!retry_message_key)
5375 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5376 US"retry_include_ip_address", ob->retry_include_ip_address,
5377 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5378 incl_ip = TRUE; /* error; use most-specific retry record */
5380 retry_message_key = incl_ip
5381 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5383 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5385 retry_add_item(addrlist, retry_message_key,
5386 rf_message | rf_host | delete_flag);
5387 update_waiting = FALSE;
5390 /* Any return other than DEFER (that is, OK or ERROR) means that the
5391 addresses have got their final statuses filled in for this host. In the OK
5392 case, see if any of them are deferred. */
5395 for (address_item * addr = addrlist; addr; addr = addr->next)
5396 if (addr->transport_return == DEFER)
5398 some_deferred = TRUE;
5402 /* If no addresses deferred or the result was ERROR, return. We do this for
5403 ERROR because a failing filter set-up or add_headers expansion is likely to
5404 fail for any host we try. */
5406 if (rc == ERROR || (rc == OK && !some_deferred))
5408 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5409 return TRUE; /* Each address has its status */
5412 /* If the result was DEFER or some individual addresses deferred, let
5413 the loop run to try other hosts with the deferred addresses, except for the
5414 case when we were trying to deliver down an existing channel and failed.
5415 Don't try any other hosts in this case. */
5417 if (continue_hostname) break;
5419 /* If the whole delivery, or some individual addresses, were deferred and
5420 there are more hosts that could be tried, do not count this host towards
5421 the hosts_max_try limit if the age of the message is greater than the
5422 maximum retry time for this host. This means we may try try all hosts,
5423 ignoring the limit, when messages have been around for some time. This is
5424 important because if we don't try all hosts, the address will never time
5425 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5427 if ((rc == DEFER || some_deferred) && nexthost)
5430 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5432 if (retry && retry->rules)
5434 retry_rule *last_rule;
5435 for (last_rule = retry->rules;
5437 last_rule = last_rule->next);
5438 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5440 else timedout = TRUE; /* No rule => timed out */
5444 unexpired_hosts_tried--;
5445 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5446 "hosts_max_try (message older than host's retry time)\n");
5452 if (unexpired_hosts_tried >= ob->hosts_max_try)
5453 debug_printf("reached transport hosts_max_try limit %d\n",
5455 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5456 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5457 ob->hosts_max_try_hardlimit);
5460 testharness_pause_ms(500); /* let server debug out */
5461 } /* End of loop for trying multiple hosts. */
5463 /* If we failed to find a matching host in the list, for an already-open
5464 connection, just close it and start over with the list. This can happen
5465 for routing that changes from run to run, or big multi-IP sites with
5468 if (continue_hostname && !continue_host_tried)
5470 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5472 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5474 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5476 /*XXX doublecheck that! */
5478 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5480 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5481 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5482 cutthrough.cctx.tls_ctx = NULL;
5483 cutthrough.is_tls = FALSE;
5487 (void) write(fd, US"QUIT\r\n", 6);
5490 cutthrough.cctx.sock = -1;
5491 continue_hostname = NULL;
5492 goto retry_non_continued;
5495 /* This is the end of the loop that repeats iff expired is TRUE and
5496 ob->delay_after_cutoff is FALSE. The second time round we will
5497 try those hosts that haven't been tried since the message arrived. */
5501 debug_printf("all IP addresses skipped or deferred at least one address\n");
5502 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5503 debug_printf("retrying IP addresses not tried since message arrived\n");
5508 /* Get here if all IP addresses are skipped or defer at least one address. In
5509 MUA wrapper mode, this will happen only for connection or other non-message-
5510 specific failures. Force the delivery status for all addresses to FAIL. */
5514 for (address_item * addr = addrlist; addr; addr = addr->next)
5515 addr->transport_return = FAIL;
5519 /* In the normal, non-wrapper case, add a standard message to each deferred
5520 address if there hasn't been an error, that is, if it hasn't actually been
5521 tried this time. The variable "expired" will be FALSE if any deliveries were
5522 actually tried, or if there was at least one host that was not expired. That
5523 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
5524 a delivery has been tried, an error code will be set, and the failing of the
5525 message is handled by the retry code later.
5527 If queue_smtp is set, or this transport was called to send a subsequent message
5528 down an existing TCP/IP connection, and something caused the host not to be
5529 found, we end up here, but can detect these cases and handle them specially. */
5531 for (address_item * addr = addrlist; addr; addr = addr->next)
5533 /* If host is not NULL, it means that we stopped processing the host list
5534 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
5535 means we need to behave as if some hosts were skipped because their retry
5536 time had not come. Specifically, this prevents the address from timing out.
5537 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
5538 hosts were tried. */
5541 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5544 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
5545 "hosts were tried\n");
5550 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
5551 setflag(addr, af_retry_skipped);
5554 if (f.queue_smtp) /* no deliveries attempted */
5556 addr->transport_return = DEFER;
5557 addr->basic_errno = 0;
5558 addr->message = US"SMTP delivery explicitly queued";
5561 else if ( addr->transport_return == DEFER
5562 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
5566 addr->basic_errno = ERRNO_HRETRY;
5567 if (continue_hostname)
5568 addr->message = US"no host found for existing SMTP connection";
5571 setflag(addr, af_pass_message); /* This is not a security risk */
5572 addr->message = string_sprintf(
5573 "all hosts%s have been failing for a long time %s",
5574 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
5575 ob->delay_after_cutoff
5576 ? US"(and retry time not reached)"
5577 : US"and were last tried after this message arrived");
5579 /* If we are already using fallback hosts, or there are no fallback hosts
5580 defined, convert the result to FAIL to cause a bounce. */
5582 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
5583 addr->transport_return = FAIL;
5588 if (hosts_retry == hosts_total)
5589 s = "retry time not reached for any host%s";
5590 else if (hosts_fail == hosts_total)
5591 s = "all host address lookups%s failed permanently";
5592 else if (hosts_defer == hosts_total)
5593 s = "all host address lookups%s failed temporarily";
5594 else if (hosts_serial == hosts_total)
5595 s = "connection limit reached for all hosts%s";
5596 else if (hosts_fail+hosts_defer == hosts_total)
5597 s = "all host address lookups%s failed";
5599 s = "some host address lookups failed and retry time "
5600 "not reached for other hosts or connection limit reached%s";
5602 addr->message = string_sprintf(s,
5603 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
5608 /* Update the database which keeps information about which messages are waiting
5609 for which hosts to become available. For some message-specific errors, the
5610 update_waiting flag is turned off because we don't want follow-on deliveries in
5611 those cases. If this transport instance is explicitly limited to one message
5612 per connection then follow-on deliveries are not possible and there's no need
5613 to create/update the per-transport wait-<transport_name> database. */
5615 if (update_waiting && tblock->connection_max_messages != 1)
5616 transport_update_waiting(hostlist, tblock->name);
5620 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5622 return TRUE; /* Each address has its status */
5625 #endif /*!MACRO_PREDEF*/
5628 /* End of transport/smtp.c */