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 != NULL) 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);
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 = 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\n", __FUNCTION__);
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)
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 } /* Loop for next RCPT response */
1228 /* Update where to start at for the next block of responses, unless we
1229 have already handled all the addresses. */
1231 if (addr) sx->sync_addr = addr->next;
1233 /* Handle a response to DATA. If we have not had any good recipients, either
1234 previously or in this block, the response is ignored. */
1236 if (pending_DATA != 0)
1238 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1239 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1240 '3', ob->command_timeout))
1246 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1249 if (pending_DATA > 0 || (yield & 1) != 0)
1251 if (errno == 0 && sx->buffer[0] == '4')
1253 errno = ERRNO_DATA4XX;
1254 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1258 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1259 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1260 "is in use and there were no good recipients\n", msg);
1264 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1265 present) received 3xx. If any RCPTs were handled and yielded anything other
1266 than 4xx, yield will be set non-zero. */
1275 /* Try an authenticator's client entry */
1278 try_authenticator(smtp_context * sx, auth_instance * au)
1280 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1281 host_item * host = sx->conn_args.host; /* host to deliver to */
1284 sx->outblock.authenticating = TRUE;
1285 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1286 sx->buffer, sizeof(sx->buffer));
1287 sx->outblock.authenticating = FALSE;
1288 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n", au->name, rc);
1290 /* A temporary authentication failure must hold up delivery to
1291 this host. After a permanent authentication failure, we carry on
1292 to try other authentication methods. If all fail hard, try to
1293 deliver the message unauthenticated unless require_auth was set. */
1298 f.smtp_authenticated = TRUE; /* stops the outer loop */
1299 client_authenticator = au->name;
1300 if (au->set_client_id)
1301 client_authenticated_id = expand_string(au->set_client_id);
1304 /* Failure after writing a command */
1309 /* Failure after reading a response */
1312 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1313 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1314 au->name, host->name, host->address, sx->buffer);
1317 /* Failure by some other means. In effect, the authenticator
1318 decided it wasn't prepared to handle this case. Typically this
1319 is the result of "fail" in an expansion string. Do we need to
1320 log anything here? Feb 2006: a message is now put in the buffer
1321 if logging is required. */
1324 if (*sx->buffer != 0)
1325 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1326 "authentication H=%s [%s] %s", au->name, host->name,
1327 host->address, sx->buffer);
1330 /* Internal problem, message in buffer. */
1333 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1334 DEFER, FALSE, &sx->delivery_start);
1343 /* Do the client side of smtp-level authentication.
1346 sx smtp connection context
1348 sx->buffer should have the EHLO response from server (gets overwritten)
1351 OK Success, or failed (but not required): global "smtp_authenticated" set
1352 DEFER Failed authentication (and was required)
1353 ERROR Internal problem
1355 FAIL_SEND Failed communications - transmit
1360 smtp_auth(smtp_context * sx)
1362 host_item * host = sx->conn_args.host; /* host to deliver to */
1363 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1364 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1365 #ifndef DISABLE_PIPE_CONNECT
1366 unsigned short authbits = tls_out.active.sock >= 0
1367 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1369 uschar * fail_reason = US"server did not advertise AUTH support";
1371 f.smtp_authenticated = FALSE;
1372 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1375 regex_AUTH = regex_must_compile(AUTHS_REGEX, FALSE, TRUE);
1377 /* Is the server offering AUTH? */
1381 #ifndef DISABLE_PIPE_CONNECT
1382 sx->early_pipe_active ? authbits
1385 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1388 uschar * names = NULL;
1389 expand_nmax = -1; /* reset */
1391 #ifndef DISABLE_PIPE_CONNECT
1392 if (!sx->early_pipe_active)
1394 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1396 /* Must not do this check until after we have saved the result of the
1397 regex match above as the check could be another RE. */
1399 if ( require_auth == OK
1400 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1402 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1403 fail_reason = US"no common mechanisms were found";
1405 #ifndef DISABLE_PIPE_CONNECT
1406 if (sx->early_pipe_active)
1408 /* Scan our authenticators (which support use by a client and were offered
1409 by the server (checked at cache-write time)), not suppressed by
1410 client_condition. If one is found, attempt to authenticate by calling its
1411 client function. We are limited to supporting up to 16 authenticator
1412 public-names by the number of bits in a short. */
1418 for (bitnum = 0, au = auths;
1419 !f.smtp_authenticated && au && bitnum < 16;
1420 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1422 if ( au->client_condition
1423 && !expand_check_condition(au->client_condition, au->name,
1424 US"client authenticator"))
1426 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1427 au->name, "client_condition is false");
1431 /* Found data for a listed mechanism. Call its client entry. Set
1432 a flag in the outblock so that data is overwritten after sending so
1433 that reflections don't show it. */
1435 fail_reason = US"authentication attempt(s) failed";
1437 if ((rc = try_authenticator(sx, au)) != OK)
1444 /* Scan the configured authenticators looking for one which is configured
1445 for use as a client, which is not suppressed by client_condition, and
1446 whose name matches an authentication mechanism supported by the server.
1447 If one is found, attempt to authenticate by calling its client function.
1450 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1455 || ( au->client_condition
1456 && !expand_check_condition(au->client_condition, au->name,
1457 US"client authenticator")))
1459 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1461 (au->client)? "client_condition is false" :
1462 "not configured as a client");
1466 /* Loop to scan supported server mechanisms */
1470 int len = Ustrlen(au->public_name);
1473 while (isspace(*p)) p++;
1475 if (strncmpic(au->public_name, p, len) != 0 ||
1476 (p[len] != 0 && !isspace(p[len])))
1478 while (*p != 0 && !isspace(*p)) p++;
1482 /* Found data for a listed mechanism. Call its client entry. Set
1483 a flag in the outblock so that data is overwritten after sending so
1484 that reflections don't show it. */
1486 fail_reason = US"authentication attempt(s) failed";
1488 if ((rc = try_authenticator(sx, au)) != OK)
1491 break; /* If not authenticated, try next authenticator */
1492 } /* Loop for scanning supported server mechanisms */
1493 } /* Loop for further authenticators */
1497 /* If we haven't authenticated, but are required to, give up. */
1499 if (require_auth == OK && !f.smtp_authenticated)
1501 invalidate_ehlo_cache_entry(sx);
1502 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1503 string_sprintf("authentication required but %s", fail_reason), DEFER,
1504 FALSE, &sx->delivery_start);
1512 /* Construct AUTH appendix string for MAIL TO */
1515 sx context for smtp connection
1516 p point in sx->buffer to build string
1517 addrlist chain of potential addresses to deliver
1519 Globals f.smtp_authenticated
1520 client_authenticated_sender
1521 Return True on error, otherwise buffer has (possibly empty) terminated string
1525 smtp_mail_auth_str(smtp_context * sx, uschar * p, address_item * addrlist)
1527 smtp_transport_options_block * ob = sx->conn_args.ob;
1528 uschar * local_authenticated_sender = authenticated_sender;
1531 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n",
1532 authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1535 if (ob->authenticated_sender)
1537 uschar * new = expand_string(ob->authenticated_sender);
1540 if (!f.expand_string_forcedfail)
1542 uschar *message = string_sprintf("failed to expand "
1543 "authenticated_sender: %s", expand_string_message);
1544 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
1549 local_authenticated_sender = new;
1552 /* Add the authenticated sender address if present */
1554 if ( (f.smtp_authenticated || ob->authenticated_sender_force)
1555 && local_authenticated_sender)
1557 string_format_nt(p, sizeof(sx->buffer) - (p-sx->buffer), " AUTH=%s",
1558 auth_xtextencode(local_authenticated_sender,
1559 Ustrlen(local_authenticated_sender)));
1560 client_authenticated_sender = string_copy(local_authenticated_sender);
1570 typedef struct smtp_compare_s
1572 uschar * current_sender_address;
1573 struct transport_instance * tblock;
1577 /* Create a unique string that identifies this message, it is based on
1578 sender_address, helo_data and tls_certificate if enabled.
1582 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1584 address_item * addr1;
1585 uschar * if1 = US"";
1586 uschar * helo1 = US"";
1588 uschar * tlsc1 = US"";
1590 uschar * save_sender_address = sender_address;
1591 uschar * local_identity = NULL;
1592 smtp_transport_options_block * ob = SOB tblock->options_block;
1594 sender_address = sender;
1596 addr1 = deliver_make_addr (sender, TRUE);
1597 deliver_set_expansions(addr1);
1600 if1 = expand_string(ob->interface);
1603 helo1 = expand_string(ob->helo_data);
1606 if (ob->tls_certificate)
1607 tlsc1 = expand_string(ob->tls_certificate);
1608 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1610 local_identity = string_sprintf ("%s^%s", if1, helo1);
1613 deliver_set_expansions(NULL);
1614 sender_address = save_sender_address;
1616 return local_identity;
1621 /* This routine is a callback that is called from transport_check_waiting.
1622 This function will evaluate the incoming message versus the previous
1623 message. If the incoming message is using a different local identity then
1624 we will veto this new message. */
1627 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1629 uschar * message_local_identity,
1630 * current_local_identity,
1631 * new_sender_address;
1633 current_local_identity =
1634 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1636 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1639 message_local_identity =
1640 smtp_local_identity(new_sender_address, s_compare->tblock);
1642 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1648 ehlo_response(uschar * buf, unsigned checks)
1650 size_t bsize = Ustrlen(buf);
1652 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1655 if ( checks & OPTION_TLS
1656 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1658 checks &= ~OPTION_TLS;
1660 if ( checks & OPTION_IGNQ
1661 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1662 PCRE_EOPT, NULL, 0) < 0)
1663 checks &= ~OPTION_IGNQ;
1665 if ( checks & OPTION_CHUNKING
1666 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1667 checks &= ~OPTION_CHUNKING;
1669 #ifndef DISABLE_PRDR
1670 if ( checks & OPTION_PRDR
1671 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1673 checks &= ~OPTION_PRDR;
1676 if ( checks & OPTION_UTF8
1677 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1679 checks &= ~OPTION_UTF8;
1681 if ( checks & OPTION_DSN
1682 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1683 checks &= ~OPTION_DSN;
1685 if ( checks & OPTION_PIPE
1686 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1687 PCRE_EOPT, NULL, 0) < 0)
1688 checks &= ~OPTION_PIPE;
1690 if ( checks & OPTION_SIZE
1691 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1692 checks &= ~OPTION_SIZE;
1694 #ifndef DISABLE_PIPE_CONNECT
1695 if ( checks & OPTION_EARLY_PIPE
1696 && pcre_exec(regex_EARLY_PIPE, NULL, CS buf, bsize, 0,
1697 PCRE_EOPT, NULL, 0) < 0)
1699 checks &= ~OPTION_EARLY_PIPE;
1701 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1707 /* Callback for emitting a BDAT data chunk header.
1709 If given a nonzero size, first flush any buffered SMTP commands
1710 then emit the command.
1712 Reap previous SMTP command responses if requested, and always reap
1713 the response from a previous BDAT command.
1716 tctx transport context
1717 chunk_size value for SMTP BDAT command
1719 tc_chunk_last add LAST option to SMTP BDAT command
1720 tc_reap_prev reap response to previous SMTP commands
1724 DEFER TLS error on first read (EHLO-resp); errno set
1728 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1731 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1732 smtp_context * sx = tctx->smtp_context;
1736 /* Write SMTP chunk header command. If not reaping responses, note that
1737 there may be more writes (like, the chunk data) done soon. */
1741 #ifndef DISABLE_PIPE_CONNECT
1742 BOOL new_conn = !!(sx->outblock.conn_args);
1744 if((cmd_count = smtp_write_command(sx,
1745 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1746 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1747 ) < 0) return ERROR;
1748 if (flags & tc_chunk_last)
1749 data_command = string_copy(big_buffer); /* Save for later error message */
1750 #ifndef DISABLE_PIPE_CONNECT
1751 /* That command write could have been the one that made the connection.
1752 Copy the fd from the client conn ctx (smtp transport specific) to the
1753 generic transport ctx. */
1756 tctx->u.fd = sx->outblock.cctx->sock;
1760 prev_cmd_count = cmd_count += sx->cmd_count;
1762 /* Reap responses for any previous, but not one we just emitted */
1766 if (sx->pending_BDAT)
1769 if (flags & tc_reap_prev && prev_cmd_count > 0)
1771 DEBUG(D_transport) debug_printf("look for %d responses"
1772 " for previous pipelined cmds\n", prev_cmd_count);
1774 switch(sync_responses(sx, prev_cmd_count, 0))
1776 case 1: /* 2xx (only) => OK */
1777 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1778 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1779 case 0: break; /* No 2xx or 5xx, but no probs */
1781 case -5: errno = ERRNO_TLSFAILURE;
1783 #ifndef DISABLE_PIPE_CONNECT
1784 case -4: /* non-2xx for pipelined banner or EHLO */
1786 case -1: /* Timeout on RCPT */
1787 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1790 if (!sx->pending_BDAT)
1791 pipelining_active = FALSE;
1794 /* Reap response for an outstanding BDAT */
1796 if (sx->pending_BDAT)
1798 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1800 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
1801 ob->command_timeout))
1803 if (errno == 0 && sx->buffer[0] == '4')
1805 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1806 sx->addrlist->more_errno |=
1807 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1812 sx->pending_BDAT = FALSE;
1813 pipelining_active = FALSE;
1815 else if (chunk_size > 0)
1816 sx->pending_BDAT = TRUE;
1819 sx->cmd_count = cmd_count;
1827 /*************************************************
1828 * Make connection for given message *
1829 *************************************************/
1833 ctx connection context
1834 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1835 a second attempt after TLS initialization fails
1837 Returns: OK - the connection was made and the delivery attempted;
1838 fd is set in the conn context, tls_out set up.
1839 DEFER - the connection could not be made, or something failed
1840 while setting up the SMTP session, or there was a
1841 non-message-specific error, such as a timeout.
1842 ERROR - helo_data or add_headers or authenticated_sender is
1843 specified for this transport, and the string failed
1847 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1849 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
1850 BOOL pass_message = FALSE;
1851 uschar * message = NULL;
1854 uschar * tls_errstr;
1857 sx->conn_args.ob = ob;
1859 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1860 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
1861 /* sx->ok = FALSE; */
1862 sx->send_rset = TRUE;
1863 sx->send_quit = TRUE;
1864 sx->setting_up = TRUE;
1866 /* sx->esmtp_sent = FALSE; */
1868 /* sx->utf8_needed = FALSE; */
1870 sx->dsn_all_lasthop = TRUE;
1872 /* sx->conn_args.dane = FALSE; */
1874 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
1876 #ifndef DISABLE_PIPE_CONNECT
1877 /* sx->early_pipe_active = sx->early_pipe_ok = FALSE; */
1878 /* sx->ehlo_resp.cleartext_features = sx->ehlo_resp.crypted_features = 0; */
1879 /* sx->pending_BANNER = sx->pending_EHLO = sx->pending_MAIL = FALSE; */
1882 if ((sx->max_rcpt = sx->conn_args.tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1883 /* sx->peer_offered = 0; */
1884 /* sx->avoid_option = 0; */
1885 sx->igquotstr = US"";
1886 if (!sx->helo_data) sx->helo_data = ob->helo_data;
1887 #ifdef EXPERIMENTAL_DSN_INFO
1888 /* sx->smtp_greeting = NULL; */
1889 /* sx->helo_response = NULL; */
1892 smtp_command = US"initial connection";
1893 /* sx->buffer[0] = '\0'; */
1895 /* Set up the buffer for reading SMTP response packets. */
1897 sx->inblock.buffer = sx->inbuffer;
1898 sx->inblock.buffersize = sizeof(sx->inbuffer);
1899 sx->inblock.ptr = sx->inbuffer;
1900 sx->inblock.ptrend = sx->inbuffer;
1902 /* Set up the buffer for holding SMTP commands while pipelining */
1904 sx->outblock.buffer = sx->outbuffer;
1905 sx->outblock.buffersize = sizeof(sx->outbuffer);
1906 sx->outblock.ptr = sx->outbuffer;
1907 /* sx->outblock.cmd_count = 0; */
1908 /* sx->outblock.authenticating = FALSE; */
1909 /* sx->outblock.conn_args = NULL; */
1911 /* Reset the parameters of a TLS session. */
1914 tls_out.cipher = NULL; /* the one we may use for this transport */
1915 tls_out.ourcert = NULL;
1916 tls_out.peercert = NULL;
1917 tls_out.peerdn = NULL;
1921 tls_out.ocsp = OCSP_NOT_REQ;
1922 #ifndef DISABLE_TLS_RESUME
1923 tls_out.resumption = 0;
1927 /* Flip the legacy TLS-related variables over to the outbound set in case
1928 they're used in the context of the transport. Don't bother resetting
1929 afterward (when being used by a transport) as we're in a subprocess.
1930 For verify, unflipped once the callout is dealt with */
1932 tls_modify_variables(&tls_out);
1937 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1938 DEFER, FALSE, &sx->delivery_start);
1943 /* If we have a proxied TLS connection, check usability for this message */
1945 if (continue_hostname && continue_proxy_cipher)
1948 const uschar * sni = US"";
1950 # ifdef SUPPORT_DANE
1951 /* Check if the message will be DANE-verified; if so force its SNI */
1953 tls_out.dane_verified = FALSE;
1954 smtp_port_for_connect(sx->conn_args.host, sx->port);
1955 if ( sx->conn_args.host->dnssec == DS_YES
1956 && ( sx->dane_required
1957 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
1959 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
1961 case OK: sx->conn_args.dane = TRUE;
1962 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
1963 ob->tls_sni = sx->first_addr->domain; /* force SNI */
1965 case FAIL_FORCED: break;
1966 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1967 string_sprintf("DANE error: tlsa lookup %s",
1969 rc, FALSE, &sx->delivery_start);
1970 # ifndef DISABLE_EVENT
1971 (void) event_raise(sx->conn_args.tblock->event_action,
1972 US"dane:fail", sx->dane_required
1973 ? US"dane-required" : US"dnssec-invalid");
1979 /* If the SNI or the DANE status required for the new message differs from the
1980 existing conn drop the connection to force a new one. */
1982 if (ob->tls_sni && !(sni = expand_cstring(ob->tls_sni)))
1983 log_write(0, LOG_MAIN|LOG_PANIC,
1984 "<%s>: failed to expand transport's tls_sni value: %s",
1985 sx->addrlist->address, expand_string_message);
1987 # ifdef SUPPORT_DANE
1988 if ( (continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni)
1989 && continue_proxy_dane == sx->conn_args.dane)
1991 tls_out.sni = US sni;
1992 if ((tls_out.dane_verified = continue_proxy_dane))
1993 sx->conn_args.host->dnssec = DS_YES;
1996 if ((continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni))
1997 tls_out.sni = US sni;
2002 debug_printf("Closing proxied-TLS connection due to SNI mismatch\n");
2004 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP>> QUIT\n");
2005 write(0, "QUIT\r\n", 6);
2007 continue_hostname = continue_proxy_cipher = NULL;
2008 f.continue_more = FALSE;
2009 continue_sequence = 1; /* Unfortunately, this process cannot affect success log
2010 which is done by delivery proc. Would have to pass this
2011 back through reporting pipe. */
2014 #endif /*!DISABLE_TLS*/
2016 /* Make a connection to the host if this isn't a continued delivery, and handle
2017 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2018 specially so they can be identified for retries. */
2020 if (!continue_hostname)
2023 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2025 /* Get the actual port the connection will use, into sx->conn_args.host */
2027 smtp_port_for_connect(sx->conn_args.host, sx->port);
2030 /* Do TLSA lookup for DANE */
2032 tls_out.dane_verified = FALSE;
2033 tls_out.tlsa_usage = 0;
2035 if (sx->conn_args.host->dnssec == DS_YES)
2038 if( sx->dane_required
2039 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2041 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2043 case OK: sx->conn_args.dane = TRUE;
2044 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2045 ob->tls_sni = sx->first_addr->domain; /* force SNI */
2047 case FAIL_FORCED: break;
2048 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2049 string_sprintf("DANE error: tlsa lookup %s",
2051 rc, FALSE, &sx->delivery_start);
2052 # ifndef DISABLE_EVENT
2053 (void) event_raise(sx->conn_args.tblock->event_action,
2054 US"dane:fail", sx->dane_required
2055 ? US"dane-required" : US"dnssec-invalid");
2060 else if (sx->dane_required)
2062 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2063 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2064 FAIL, FALSE, &sx->delivery_start);
2065 # ifndef DISABLE_EVENT
2066 (void) event_raise(sx->conn_args.tblock->event_action,
2067 US"dane:fail", US"dane-required");
2074 /* Make the TCP connection */
2076 sx->cctx.tls_ctx = NULL;
2077 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2078 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2080 #ifndef DISABLE_PIPE_CONNECT
2081 if ( verify_check_given_host(CUSS &ob->hosts_pipe_connect,
2082 sx->conn_args.host) == OK)
2084 /* We don't find out the local ip address until the connect, so if
2085 the helo string might use it avoid doing early-pipelining. */
2088 || !Ustrstr(sx->helo_data, "$sending_ip_address")
2089 || Ustrstr(sx->helo_data, "def:sending_ip_address")
2092 sx->early_pipe_ok = TRUE;
2093 if ( read_ehlo_cache_entry(sx)
2094 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2097 debug_printf("Using cached cleartext PIPE_CONNECT\n");
2098 sx->early_pipe_active = TRUE;
2099 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2102 else DEBUG(D_transport)
2103 debug_printf("helo needs $sending_ip_address\n");
2106 if (sx->early_pipe_active)
2107 sx->outblock.conn_args = &sx->conn_args;
2111 blob lazy_conn = {.data = NULL};
2112 /* For TLS-connect, a TFO lazy-connect is useful since the Client Hello
2113 can go on the TCP SYN. */
2115 if ((sx->cctx.sock = smtp_connect(&sx->conn_args,
2116 sx->smtps ? &lazy_conn : NULL)) < 0)
2118 set_errno_nohost(sx->addrlist,
2119 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2120 sx->verify ? US strerror(errno) : NULL,
2121 DEFER, FALSE, &sx->delivery_start);
2122 sx->send_quit = FALSE;
2126 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2130 /* Expand the greeting message while waiting for the initial response. (Makes
2131 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2132 delayed till here so that $sending_interface and $sending_port are set. */
2133 /*XXX early-pipe: they still will not be. Is there any way to find out what they
2134 will be? Somehow I doubt it. */
2137 if (!(sx->helo_data = expand_string(sx->helo_data)))
2139 log_write(0, LOG_MAIN|LOG_PANIC,
2140 "<%s>: failed to expand transport's helo_data value for callout: %s",
2141 sx->addrlist->address, expand_string_message);
2146 expand_string_message = NULL;
2147 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2148 &expand_string_message)),
2149 expand_string_message)
2151 log_write(0, LOG_MAIN|LOG_PANIC,
2152 "<%s>: failed to expand transport's helo_data value for callout: %s",
2153 sx->addrlist->address, expand_string_message);
2155 sx->helo_data = NULL;
2159 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2160 is nevertheless a reasonably clean way of programming this kind of logic,
2161 where you want to escape on any error. */
2165 #ifndef DISABLE_PIPE_CONNECT
2166 if (sx->early_pipe_active)
2168 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2169 sx->outblock.cmd_count = 1;
2174 if (!smtp_reap_banner(sx))
2175 goto RESPONSE_FAILED;
2178 #ifndef DISABLE_EVENT
2181 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2182 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2183 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer);
2186 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2187 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2188 DEFER, FALSE, &sx->delivery_start);
2195 /* Now check if the helo_data expansion went well, and sign off cleanly if
2200 message = string_sprintf("failed to expand helo_data: %s",
2201 expand_string_message);
2202 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2208 /** Debugging without sending a message
2209 sx->addrlist->transport_return = DEFER;
2213 /* Errors that occur after this point follow an SMTP command, which is
2214 left in big_buffer by smtp_write_command() for use in error messages. */
2216 smtp_command = big_buffer;
2218 /* Tell the remote who we are...
2220 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2221 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2222 greeting is of this form. The assumption was that the far end supports it
2223 properly... but experience shows that there are some that give 5xx responses,
2224 even though the banner includes "ESMTP" (there's a bloody-minded one that
2225 says "ESMTP not spoken here"). Cope with that case.
2227 September 2000: Time has passed, and it seems reasonable now to always send
2228 EHLO at the start. It is also convenient to make the change while installing
2231 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2232 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2233 would be no way to send out the mails, so there is now a host list
2234 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2235 PIPELINING problem as well. Maybe it can also be useful to cure other
2236 problems with broken servers.
2238 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2239 Then somebody tried it with a Microsoft mailer... It seems that all other
2240 mailers use upper case for some reason (the RFC is quite clear about case
2241 independence) so, for peace of mind, I gave in. */
2243 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2245 /* Alas; be careful, since this goto is not an error-out, so conceivably
2246 we might set data between here and the target which we assume to exist
2247 and be usable. I can see this coming back to bite us. */
2251 smtp_peer_options |= OPTION_TLS;
2252 suppress_tls = FALSE;
2253 ob->tls_tempfail_tryclear = FALSE;
2254 smtp_command = US"SSL-on-connect";
2261 if (smtp_write_command(sx,
2262 #ifndef DISABLE_PIPE_CONNECT
2263 sx->early_pipe_active ? SCMD_BUFFER :
2266 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2268 sx->esmtp_sent = TRUE;
2270 #ifndef DISABLE_PIPE_CONNECT
2271 if (sx->early_pipe_active)
2273 sx->pending_EHLO = TRUE;
2275 /* If we have too many authenticators to handle and might need to AUTH
2276 for this transport, pipeline no further as we will need the
2277 list of auth methods offered. Reap the banner and EHLO. */
2279 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2280 && f.smtp_in_early_pipe_no_auth)
2282 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2283 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2285 if (sync_responses(sx, 2, 0) != 0)
2288 debug_printf("failed reaping pipelined cmd responses\n");
2289 goto RESPONSE_FAILED;
2291 sx->early_pipe_active = FALSE;
2296 if (!smtp_reap_ehlo(sx))
2297 goto RESPONSE_FAILED;
2301 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2303 #ifndef DISABLE_PIPE_CONNECT
2304 if (!sx->early_pipe_active)
2309 int n = sizeof(sx->buffer);
2310 uschar * rsp = sx->buffer;
2312 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
2313 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
2315 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2317 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2318 #ifdef EXPERIMENTAL_DSN_INFO
2319 sx->helo_response = string_copy(rsp);
2323 /* Handle special logging for a closed connection after HELO
2324 when had previously sent EHLO */
2326 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2328 errno = ERRNO_SMTPCLOSED;
2329 goto EHLOHELO_FAILED;
2331 memmove(sx->buffer, rsp, Ustrlen(rsp));
2332 goto RESPONSE_FAILED;
2336 if (sx->esmtp || sx->lmtp)
2338 #ifndef DISABLE_PIPE_CONNECT
2339 if (!sx->early_pipe_active)
2342 sx->peer_offered = ehlo_response(sx->buffer,
2343 OPTION_TLS /* others checked later */
2344 #ifndef DISABLE_PIPE_CONNECT
2345 | (sx->early_pipe_ok
2347 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2356 #ifndef DISABLE_PIPE_CONNECT
2357 if (sx->early_pipe_ok)
2359 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2361 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2362 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2364 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2365 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2366 write_ehlo_cache_entry(sx);
2372 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2375 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2380 /* For continuing deliveries down the same channel, having re-exec'd the socket
2381 is the standard input; for a socket held open from verify it is recorded
2382 in the cutthrough context block. Either way we don't need to redo EHLO here
2383 (but may need to do so for TLS - see below).
2384 Set up the pointer to where subsequent commands will be left, for
2385 error messages. Note that smtp_peer_options will have been
2386 set from the command line if they were set in the process that passed the
2389 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2390 as the continue goes via transport_pass_socket() and doublefork and exec.
2391 It does not wait. Unclear how we keep separate host's responses
2392 separate - we could match up by host ip+port as a bodge. */
2396 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2398 sx->cctx = cutthrough.cctx;
2399 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2403 sx->cctx.sock = 0; /* stdin */
2404 sx->cctx.tls_ctx = NULL;
2405 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2407 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2408 smtp_command = big_buffer;
2409 sx->peer_offered = smtp_peer_options;
2410 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2412 /* For a continued connection with TLS being proxied for us, or a
2413 held-open verify connection with TLS, nothing more to do. */
2415 if ( continue_proxy_cipher
2416 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2417 && cutthrough.is_tls)
2420 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2421 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2422 continue_proxy_cipher ? "proxied" : "verify conn with");
2425 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2428 /* If TLS is available on this connection, whether continued or not, attempt to
2429 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2430 send another EHLO - the server may give a different answer in secure mode. We
2431 use a separate buffer for reading the response to STARTTLS so that if it is
2432 negative, the original EHLO data is available for subsequent analysis, should
2433 the client not be required to use TLS. If the response is bad, copy the buffer
2434 for error analysis. */
2437 if ( smtp_peer_options & OPTION_TLS
2439 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2441 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2444 uschar buffer2[4096];
2446 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2449 #ifndef DISABLE_PIPE_CONNECT
2450 /* If doing early-pipelining reap the banner and EHLO-response but leave
2451 the response for the STARTTLS we just sent alone. */
2453 if (sx->early_pipe_active && sync_responses(sx, 2, 0) != 0)
2456 debug_printf("failed reaping pipelined cmd responses\n");
2457 close(sx->cctx.sock);
2459 sx->early_pipe_active = FALSE;
2460 goto PIPE_CONNECT_RETRY;
2464 /* If there is an I/O error, transmission of this message is deferred. If
2465 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2466 false, we also defer. However, if there is a temporary rejection of STARTTLS
2467 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2468 STARTTLS, we carry on. This means we will try to send the message in clear,
2469 unless the host is in hosts_require_tls (tested below). */
2471 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2475 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2478 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2479 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2480 goto RESPONSE_FAILED;
2484 /* STARTTLS accepted: try to negotiate a TLS session. */
2489 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2491 /* TLS negotiation failed; give an error. From outside, this function may
2492 be called again to try in clear on a new connection, if the options permit
2493 it for this host. */
2495 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2497 # ifdef SUPPORT_DANE
2498 if (sx->conn_args.dane)
2500 log_write(0, LOG_MAIN,
2501 "DANE attempt failed; TLS connection to %s [%s]: %s",
2502 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2503 # ifndef DISABLE_EVENT
2504 (void) event_raise(sx->conn_args.tblock->event_action,
2505 US"dane:fail", US"validation-failure"); /* could do with better detail */
2510 errno = ERRNO_TLSFAILURE;
2511 message = string_sprintf("TLS session: %s", tls_errstr);
2512 sx->send_quit = FALSE;
2516 /* TLS session is set up. Check the inblock fill level. If there is
2517 content then as we have not yet done a tls read it must have arrived before
2518 the TLS handshake, in-clear. That violates the sync requirement of the
2519 STARTTLS RFC, so fail. */
2521 if (sx->inblock.ptr != sx->inblock.ptrend)
2525 int i = sx->inblock.ptrend - sx->inblock.ptr;
2526 debug_printf("unused data in input buffer after ack for STARTTLS:\n"
2528 i > 100 ? 100 : i, sx->inblock.ptr, i > 100 ? "..." : "");
2530 tls_errstr = US"synch error before connect";
2531 goto TLS_CONN_FAILED;
2534 smtp_peer_options_wrap = smtp_peer_options;
2535 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2536 if (addr->transport_return == PENDING_DEFER)
2538 addr->cipher = tls_out.cipher;
2539 addr->ourcert = tls_out.ourcert;
2540 addr->peercert = tls_out.peercert;
2541 addr->peerdn = tls_out.peerdn;
2542 addr->ocsp = tls_out.ocsp;
2543 addr->tlsver = tls_out.ver;
2548 /* if smtps, we'll have smtp_command set to something else; always safe to
2550 smtp_command = big_buffer;
2552 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2553 helo_data is null, we are dealing with a connection that was passed from
2554 another process, and so we won't have expanded helo_data above. We have to
2555 expand it here. $sending_ip_address and $sending_port are set up right at the
2556 start of the Exim process (in exim.c). */
2558 if (tls_out.active.sock >= 0)
2560 uschar * greeting_cmd;
2562 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2564 uschar *message = string_sprintf("failed to expand helo_data: %s",
2565 expand_string_message);
2566 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2571 #ifndef DISABLE_PIPE_CONNECT
2572 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2573 We're unlikely to get the group sent and delivered before the server sends its
2574 banner, but it's still worth sending as a group.
2575 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2578 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2580 sx->peer_offered = sx->ehlo_resp.crypted_features;
2581 if ((sx->early_pipe_active =
2582 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2583 DEBUG(D_transport) debug_printf("Using cached crypted PIPE_CONNECT\n");
2587 /* For SMTPS we need to wait for the initial OK response. */
2589 #ifndef DISABLE_PIPE_CONNECT
2590 if (sx->early_pipe_active)
2592 sx->pending_BANNER = TRUE;
2593 sx->outblock.cmd_count = 1;
2597 if (!smtp_reap_banner(sx))
2598 goto RESPONSE_FAILED;
2601 greeting_cmd = US"LHLO";
2603 greeting_cmd = US"EHLO";
2606 greeting_cmd = US"HELO";
2608 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2611 if (smtp_write_command(sx,
2612 #ifndef DISABLE_PIPE_CONNECT
2613 sx->early_pipe_active ? SCMD_BUFFER :
2616 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2619 #ifndef DISABLE_PIPE_CONNECT
2620 if (sx->early_pipe_active)
2621 sx->pending_EHLO = TRUE;
2625 if (!smtp_reap_ehlo(sx))
2628 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2629 cert late, under TLS1.3 - which means here; the first time we try to
2630 receive crypted data. Treat it as if it was a connect-time failure.
2631 See also the early-pipe equivalent... which will be hard; every call
2632 to sync_responses will need to check the result.
2633 It would be nicer to have GnuTLS check the cert during the handshake.
2634 Can it do that, with all the flexibility we need? */
2636 tls_errstr = US"error on first read";
2637 goto TLS_CONN_FAILED;
2640 goto RESPONSE_FAILED;
2642 smtp_peer_options = 0;
2646 /* If the host is required to use a secure channel, ensure that we
2650 # ifdef SUPPORT_DANE
2651 || sx->conn_args.dane
2653 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2656 errno = ERRNO_TLSREQUIRED;
2657 message = string_sprintf("a TLS session is required, but %s",
2658 smtp_peer_options & OPTION_TLS
2659 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2660 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2661 if (sx->conn_args.dane)
2662 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2663 smtp_peer_options & OPTION_TLS
2664 ? US"validation-failure" /* could do with better detail */
2665 : US"starttls-not-supported");
2669 #endif /*DISABLE_TLS*/
2671 /* If TLS is active, we have just started it up and re-done the EHLO command,
2672 so its response needs to be analyzed. If TLS is not active and this is a
2673 continued session down a previously-used socket, we haven't just done EHLO, so
2676 if (continue_hostname == NULL
2678 || tls_out.active.sock >= 0
2682 if (sx->esmtp || sx->lmtp)
2684 #ifndef DISABLE_PIPE_CONNECT
2685 if (!sx->early_pipe_active)
2688 sx->peer_offered = ehlo_response(sx->buffer,
2690 #ifndef DISABLE_PIPE_CONNECT
2691 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2692 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2693 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2694 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2698 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2701 # ifdef SUPPORT_I18N
2702 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2703 /*XXX if we hand peercaps on to continued-conn processes,
2704 must not depend on this addr */
2708 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2711 #ifndef DISABLE_PIPE_CONNECT
2712 if (tls_out.active.sock >= 0)
2713 sx->ehlo_resp.crypted_features = sx->peer_offered;
2717 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2718 lmtp_ignore_quota option was set. */
2720 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2722 /* If the response to EHLO specified support for the SIZE parameter, note
2723 this, provided size_addition is non-negative. */
2725 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2727 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2728 the current host, esmtp will be false, so PIPELINING can never be used. If
2729 the current host matches hosts_avoid_pipelining, don't do it. */
2731 if ( sx->peer_offered & OPTION_PIPE
2732 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
2733 smtp_peer_options |= OPTION_PIPE;
2735 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2736 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2738 if ( sx->peer_offered & OPTION_CHUNKING
2739 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) != OK)
2740 sx->peer_offered &= ~OPTION_CHUNKING;
2742 if (sx->peer_offered & OPTION_CHUNKING)
2743 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
2745 #ifndef DISABLE_PRDR
2746 if ( sx->peer_offered & OPTION_PRDR
2747 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) != OK)
2748 sx->peer_offered &= ~OPTION_PRDR;
2750 if (sx->peer_offered & OPTION_PRDR)
2751 DEBUG(D_transport) debug_printf("PRDR usable\n");
2754 /* Note if the server supports DSN */
2755 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2756 DEBUG(D_transport) debug_printf("%susing DSN\n",
2757 sx->peer_offered & OPTION_DSN ? "" : "not ");
2759 #ifndef DISABLE_PIPE_CONNECT
2760 if ( sx->early_pipe_ok
2761 && !sx->early_pipe_active
2762 && tls_out.active.sock >= 0
2763 && smtp_peer_options & OPTION_PIPE
2764 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
2765 & OPTION_EARLY_PIPE)
2767 DEBUG(D_transport) debug_printf("PIPE_CONNECT usable in future for this IP\n");
2768 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
2769 write_ehlo_cache_entry(sx);
2773 /* Note if the response to EHLO specifies support for the AUTH extension.
2774 If it has, check that this host is one we want to authenticate to, and do
2775 the business. The host name and address must be available when the
2776 authenticator's client driver is running. */
2778 switch (yield = smtp_auth(sx))
2780 default: goto SEND_QUIT;
2782 case FAIL_SEND: goto SEND_FAILED;
2783 case FAIL: goto RESPONSE_FAILED;
2787 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2789 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2790 message-specific. */
2792 sx->setting_up = FALSE;
2795 if (sx->addrlist->prop.utf8_msg)
2799 /* If the transport sets a downconversion mode it overrides any set by ACL
2802 if ((s = ob->utf8_downconvert))
2804 if (!(s = expand_string(s)))
2806 message = string_sprintf("failed to expand utf8_downconvert: %s",
2807 expand_string_message);
2808 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2814 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
2815 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2817 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
2818 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
2820 case '-': if (s[1] == '1')
2822 sx->addrlist->prop.utf8_downcvt = FALSE;
2823 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
2829 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2830 && !sx->addrlist->prop.utf8_downcvt_maybe;
2831 DEBUG(D_transport) if (!sx->utf8_needed)
2832 debug_printf("utf8: %s downconvert\n",
2833 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2836 /* If this is an international message we need the host to speak SMTPUTF8 */
2837 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2839 errno = ERRNO_UTF8_FWD;
2840 goto RESPONSE_FAILED;
2842 #endif /*SUPPORT_I18N*/
2851 if (errno == ECONNREFUSED) /* first-read error on a TFO conn */
2853 /* There is a testing facility for simulating a connection timeout, as I
2854 can't think of any other way of doing this. It converts a connection
2855 refused into a timeout if the timeout is set to 999999. This is done for
2856 a 3whs connection in ip_connect(), but a TFO connection does not error
2857 there - instead it gets ECONNREFUSED on the first data read. Tracking
2858 that a TFO really was done is too hard, or we would set a
2859 sx->pending_conn_done bit and test that in smtp_reap_banner() and
2860 smtp_reap_ehlo(). That would let us also add the conn-timeout to the
2863 if (f.running_in_test_harness && ob->connect_timeout == 999999)
2865 set_errno_nohost(sx->addrlist,
2866 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2867 sx->verify ? US strerror(errno) : NULL,
2868 DEFER, FALSE, &sx->delivery_start);
2869 sx->send_quit = FALSE;
2873 /* really an error on an SMTP read */
2875 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
2876 sx->buffer, &code, &message, &pass_message);
2882 message = US string_sprintf("send() to %s [%s] failed: %s",
2883 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
2884 sx->send_quit = FALSE;
2890 message = string_sprintf("Remote host closed connection in response to %s"
2891 " (EHLO response was: %s)", smtp_command, sx->buffer);
2892 sx->send_quit = FALSE;
2896 /* This label is jumped to directly when a TLS negotiation has failed,
2897 or was not done for a host for which it is required. Values will be set
2898 in message and errno, and setting_up will always be true. Treat as
2899 a temporary error. */
2903 code = '4', yield = DEFER;
2907 /* The failure happened while setting up the call; see if the failure was
2908 a 5xx response (this will either be on connection, or following HELO - a 5xx
2909 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2910 fail all addresses, as this host is never going to accept them. For other
2911 errors during setting up (timeouts or whatever), defer all addresses, and
2912 yield DEFER, so that the host is not tried again for a while.
2914 XXX This peeking for another host feels like a layering violation. We want
2915 to note the host as unusable, but down here we shouldn't know if this was
2916 the last host to try for the addr(list). Perhaps the upper layer should be
2917 the one to do set_errno() ? The problem is that currently the addr is where
2918 errno etc. are stashed, but until we run out of hosts to try the errors are
2919 host-specific. Maybe we should enhance the host_item definition? */
2922 sx->ok = FALSE; /* For when reached by GOTO */
2923 set_errno(sx->addrlist, errno, message,
2924 sx->conn_args.host->next
2928 || errno == ERRNO_UTF8_FWD
2932 errno == ECONNREFUSED ? NULL : sx->conn_args.host,
2933 #ifdef EXPERIMENTAL_DSN_INFO
2934 sx->smtp_greeting, sx->helo_response,
2936 &sx->delivery_start);
2943 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
2946 if (sx->cctx.tls_ctx)
2948 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
2949 sx->cctx.tls_ctx = NULL;
2953 /* Close the socket, and return the appropriate value, first setting
2954 works because the NULL setting is passed back to the calling process, and
2955 remote_max_parallel is forced to 1 when delivering over an existing connection,
2958 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2961 shutdown(sx->cctx.sock, SHUT_WR);
2962 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
2963 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
2964 i--; /* drain socket */
2965 sx->send_quit = FALSE;
2967 (void)close(sx->cctx.sock);
2970 #ifndef DISABLE_EVENT
2971 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL);
2974 continue_transport = NULL;
2975 continue_hostname = NULL;
2982 /* Create the string of options that will be appended to the MAIL FROM:
2983 in the connection context buffer */
2986 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2988 uschar * p = sx->buffer;
2989 address_item * addr;
2994 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2995 send it, adding something to the message size to allow for imprecision
2996 and things that get added en route. Exim keeps the number of lines
2997 in a message, so we can give an accurate value for the original message, but we
2998 need some additional to handle added headers. (Double "." characters don't get
2999 included in the count.) */
3001 if ( message_size > 0
3002 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
3004 /*XXX problem here under spool_files_wireformat?
3005 Or just forget about lines? Or inflate by a fixed proportion? */
3007 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
3011 #ifndef DISABLE_PRDR
3012 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
3015 sx->prdr_active = FALSE;
3016 if (sx->peer_offered & OPTION_PRDR)
3017 for (address_item * addr = addrlist; addr; addr = addr->next)
3018 if (addr->transport_return == PENDING_DEFER)
3020 for (addr = addr->next; addr; addr = addr->next)
3021 if (addr->transport_return == PENDING_DEFER)
3022 { /* at least two recipients to send */
3023 sx->prdr_active = TRUE;
3024 sprintf(CS p, " PRDR"); p += 5;
3032 /* If it supports internationalised messages, and this meesage need that,
3035 if ( sx->peer_offered & OPTION_UTF8
3036 && addrlist->prop.utf8_msg
3037 && !addrlist->prop.utf8_downcvt
3039 Ustrcpy(p, US" SMTPUTF8"), p += 9;
3042 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3043 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3044 addr && address_count < sx->max_rcpt;
3045 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3048 if (!(addr->dsn_flags & rf_dsnlasthop))
3050 sx->dsn_all_lasthop = FALSE;
3055 /* Add any DSN flags to the mail command */
3057 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3059 if (dsn_ret == dsn_ret_hdrs)
3060 { Ustrcpy(p, US" RET=HDRS"); p += 9; }
3061 else if (dsn_ret == dsn_ret_full)
3062 { Ustrcpy(p, US" RET=FULL"); p += 9; }
3066 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3071 /* If an authenticated_sender override has been specified for this transport
3072 instance, expand it. If the expansion is forced to fail, and there was already
3073 an authenticated_sender for this message, the original value will be used.
3074 Other expansion failures are serious. An empty result is ignored, but there is
3075 otherwise no check - this feature is expected to be used with LMTP and other
3076 cases where non-standard addresses (e.g. without domains) might be required. */
3078 return smtp_mail_auth_str(sx, p, addrlist) ? ERROR : OK;
3083 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3085 uschar * p = sx->buffer;
3088 /* Add any DSN flags to the rcpt command */
3090 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3092 if (addr->dsn_flags & rf_dsnflags)
3096 Ustrcpy(p, US" NOTIFY=");
3098 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3100 if (!first) *p++ = ',';
3102 Ustrcpy(p, rf_names[i]);
3107 if (addr->dsn_orcpt)
3109 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3120 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3121 -1 MAIL response error
3122 -2 any non-MAIL read i/o error
3123 -3 non-MAIL response timeout
3124 -4 internal error; channel still usable
3129 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3131 address_item * addr;
3132 int address_count, pipe_limit;
3135 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3141 /* From here until we send the DATA command, we can make use of PIPELINING
3142 if the server host supports it. The code has to be able to check the responses
3143 at any point, for when the buffer fills up, so we write it totally generally.
3144 When PIPELINING is off, each command written reports that it has flushed the
3147 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3150 uschar * s = sx->from_addr;
3152 uschar * errstr = NULL;
3154 /* If we must downconvert, do the from-address here. Remember we had to
3155 for the to-addresses (done below), and also (ugly) for re-doing when building
3156 the delivery log line. */
3158 if ( sx->addrlist->prop.utf8_msg
3159 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3162 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3164 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, &sx->delivery_start);
3168 setflag(sx->addrlist, af_utf8_downcvt);
3172 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3173 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3176 mail_command = string_copy(big_buffer); /* Save for later error message */
3180 case -1: /* Transmission error */
3183 case +1: /* Cmd was sent */
3184 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3185 (SOB sx->conn_args.ob)->command_timeout))
3187 if (errno == 0 && sx->buffer[0] == '4')
3189 errno = ERRNO_MAIL4XX;
3190 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3194 sx->pending_MAIL = FALSE;
3197 /* otherwise zero: command queued for pipeline */
3200 /* Pass over all the relevant recipient addresses for this host, which are the
3201 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3202 several before we have to read the responses for those seen so far. This
3203 checking is done by a subroutine because it also needs to be done at the end.
3204 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3205 the next one if not all are sent.
3207 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3208 last address because we want to abort if any recipients have any kind of
3209 problem, temporary or permanent. We know that all recipient addresses will have
3210 the PENDING_DEFER status, because only one attempt is ever made, and we know
3211 that max_rcpt will be large, so all addresses will be done at once.
3213 For verify we flush the pipeline after any (the only) rcpt address. */
3215 for (addr = sx->first_addr, address_count = 0, pipe_limit = 100;
3216 addr && address_count < sx->max_rcpt;
3217 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3223 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3224 ? dsn_support_yes : dsn_support_no;
3227 if (pipe_limit-- <= 0)
3228 { no_flush = FALSE; pipe_limit = 100; }
3230 no_flush = pipelining_active && !sx->verify
3231 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3233 build_rcptcmd_options(sx, addr);
3235 /* Now send the RCPT command, and process outstanding responses when
3236 necessary. After a timeout on RCPT, we just end the function, leaving the
3237 yield as OK, because this error can often mean that there is a problem with
3238 just one address, so we don't want to delay the host. */
3240 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3243 if ( testflag(sx->addrlist, af_utf8_downcvt)
3244 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3247 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3248 errno = ERRNO_EXPANDFAIL;
3249 return -5; /*XXX too harsh? */
3253 cmds_sent = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3254 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3256 if (cmds_sent < 0) return -5;
3259 switch(sync_responses(sx, cmds_sent, 0))
3261 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3262 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3265 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3266 if (!sx->lmtp) /* can't tell about progress yet */
3267 sx->completed_addr = TRUE;
3268 case 0: /* No 2xx or 5xx, but no probs */
3269 /* If any RCPT got a 452 response then next_addr has been updated
3270 for restarting with a new MAIL on the same connection. Send no more
3271 RCPTs for this MAIL. */
3275 DEBUG(D_transport) debug_printf("seen 452 too-many-rcpts\n");
3276 sx->RCPT_452 = FALSE;
3277 /* sx->next_addr has been reset for fast_retry */
3282 case -1: return -3; /* Timeout on RCPT */
3283 case -2: return -2; /* non-MAIL read i/o error */
3284 default: return -1; /* any MAIL error */
3286 #ifndef DISABLE_PIPE_CONNECT
3287 case -4: return -1; /* non-2xx for pipelined banner or EHLO */
3288 case -5: return -1; /* TLS first-read error */
3292 } /* Loop for next address */
3294 sx->next_addr = addr;
3300 /*****************************************************
3301 * Proxy TLS connection for another transport process *
3302 ******************************************************/
3304 Close the unused end of the pipe, fork once more, then use the given buffer
3305 as a staging area, and select on both the given fd and the TLS'd client-fd for
3306 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3307 Do blocking full-size writes, and reads under a timeout. Once both input
3308 channels are closed, exit the process.
3312 buf space to use for buffering
3313 bufsiz size of buffer
3314 pfd pipe filedescriptor array; [0] is comms to proxied process
3315 timeout per-read timeout, seconds
3321 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3325 int max_fd = MAX(pfd[0], tls_out.active.sock) + 1;
3329 if ((rc = exim_fork(US"tls-proxy")))
3330 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3332 set_process_info("proxying TLS connection for continued transport");
3334 FD_SET(tls_out.active.sock, &rfds);
3335 FD_SET(pfd[0], &rfds);
3337 for (int fd_bits = 3; fd_bits; )
3339 time_t time_left = timeout;
3340 time_t time_start = time(NULL);
3346 struct timeval tv = { time_left, 0 };
3349 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
3351 if (rc < 0 && errno == EINTR)
3352 if ((time_left -= time(NULL) - time_start) > 0) continue;
3356 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3360 if (FD_ISSET(tls_out.active.sock, &efds) || FD_ISSET(pfd[0], &efds))
3362 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3363 FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
3367 while (rc < 0 || !(FD_ISSET(tls_out.active.sock, &rfds) || FD_ISSET(pfd[0], &rfds)));
3369 /* handle inbound data */
3370 if (FD_ISSET(tls_out.active.sock, &rfds))
3371 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0)
3374 FD_CLR(tls_out.active.sock, &rfds);
3375 shutdown(pfd[0], SHUT_WR);
3380 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3381 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3383 else if (fd_bits & 1)
3384 FD_SET(tls_out.active.sock, &rfds);
3386 /* handle outbound data */
3387 if (FD_ISSET(pfd[0], &rfds))
3388 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3391 tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3396 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3397 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3400 else if (fd_bits & 2)
3401 FD_SET(pfd[0], &rfds);
3405 testharness_pause_ms(100); /* let logging complete */
3406 exim_exit(EXIT_SUCCESS);
3411 /*************************************************
3412 * Deliver address list to given host *
3413 *************************************************/
3415 /* If continue_hostname is not null, we get here only when continuing to
3416 deliver down an existing channel. The channel was passed as the standard
3417 input. TLS is never active on a passed channel; the previous process either
3418 closes it down before passing the connection on, or inserts a TLS-proxy
3419 process and passes on a cleartext conection.
3421 Otherwise, we have to make a connection to the remote host, and do the
3422 initial protocol exchange.
3424 When running as an MUA wrapper, if the sender or any recipient is rejected,
3425 temporarily or permanently, we force failure for all recipients.
3428 addrlist chain of potential addresses to deliver; only those whose
3429 transport_return field is set to PENDING_DEFER are currently
3430 being processed; others should be skipped - they have either
3431 been delivered to an earlier host or IP address, or been
3432 failed by one of them.
3433 host host to deliver to
3434 host_af AF_INET or AF_INET6
3435 defport default TCP/IP port to use if host does not specify, in host
3437 interface interface to bind to, or NULL
3438 tblock transport instance block
3439 message_defer set TRUE if yield is OK, but all addresses were deferred
3440 because of a non-recipient, non-host failure, that is, a
3441 4xx response to MAIL FROM, DATA, or ".". This is a defer
3442 that is specific to the message.
3443 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3444 a second attempt after TLS initialization fails
3446 Returns: OK - the connection was made and the delivery attempted;
3447 the result for each address is in its data block.
3448 DEFER - the connection could not be made, or something failed
3449 while setting up the SMTP session, or there was a
3450 non-message-specific error, such as a timeout.
3451 ERROR - a filter command is specified for this transport,
3452 and there was a problem setting it up; OR helo_data
3453 or add_headers or authenticated_sender is specified
3454 for this transport, and the string failed to expand
3456 For all non-OK returns the first addr of the list carries the
3457 time taken for the attempt.
3461 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3462 uschar *interface, transport_instance *tblock,
3463 BOOL *message_defer, BOOL suppress_tls)
3465 smtp_transport_options_block * ob = SOB tblock->options_block;
3470 BOOL pass_message = FALSE;
3471 uschar *message = NULL;
3472 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3473 smtp_context * sx = store_get(sizeof(*sx), TRUE); /* tainted, for the data buffers */
3478 *message_defer = FALSE;
3480 memset(sx, 0, sizeof(*sx));
3481 sx->addrlist = addrlist;
3482 sx->conn_args.host = host;
3483 sx->conn_args.host_af = host_af,
3485 sx->conn_args.interface = interface;
3486 sx->helo_data = NULL;
3487 sx->conn_args.tblock = tblock;
3488 /* sx->verify = FALSE; */
3489 gettimeofday(&sx->delivery_start, NULL);
3490 sx->sync_addr = sx->first_addr = addrlist;
3497 /* Get the channel set up ready for a message, MAIL FROM being the next
3498 SMTP command to send. */
3500 if ((rc = smtp_setup_conn(sx, suppress_tls)) != OK)
3502 timesince(&addrlist->delivery_time, &sx->delivery_start);
3508 /* If the connection used DANE, ignore for now any addresses with incompatible
3509 domains. The SNI has to be the domain. Arrange a whole new TCP conn later,
3510 just in case only TLS isn't enough. */
3512 if (sx->conn_args.dane)
3514 const uschar * dane_domain = sx->first_addr->domain;
3516 for (address_item * a = sx->first_addr->next; a; a = a->next)
3517 if ( a->transport_return == PENDING_DEFER
3518 && Ustrcmp(dane_domain, a->domain) != 0)
3520 DEBUG(D_transport) debug_printf("DANE: holding %s for later\n", a->domain);
3522 a->transport_return = DANE;
3527 /* If there is a filter command specified for this transport, we can now
3528 set it up. This cannot be done until the identity of the host is known. */
3530 if (tblock->filter_command)
3532 transport_filter_timeout = tblock->filter_timeout;
3534 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3537 if (!transport_set_up_command(&transport_filter_argv,
3538 tblock->filter_command, TRUE, DEFER, addrlist,
3539 string_sprintf("%.50s transport", tblock->name), NULL))
3541 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3542 FALSE, &sx->delivery_start);
3547 if ( transport_filter_argv
3548 && *transport_filter_argv
3549 && **transport_filter_argv
3550 && sx->peer_offered & OPTION_CHUNKING
3551 #ifndef DISABLE_DKIM
3552 /* When dkim signing, chunking is handled even with a transport-filter */
3553 && !(ob->dkim.dkim_private_key && ob->dkim.dkim_domain && ob->dkim.dkim_selector)
3554 && !ob->dkim.force_bodyhash
3558 sx->peer_offered &= ~OPTION_CHUNKING;
3559 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3563 /* For messages that have more than the maximum number of envelope recipients,
3564 we want to send several transactions down the same SMTP connection. (See
3565 comments in deliver.c as to how this reconciles, heuristically, with
3566 remote_max_parallel.) This optimization was added to Exim after the following
3567 code was already working. The simplest way to put it in without disturbing the
3568 code was to use a goto to jump back to this point when there is another
3569 transaction to handle. */
3572 sx->from_addr = return_path;
3573 sx->sync_addr = sx->first_addr;
3575 sx->send_rset = TRUE;
3576 sx->completed_addr = FALSE;
3579 /* If we are a continued-connection-after-verify the MAIL and RCPT
3580 commands were already sent; do not re-send but do mark the addrs as
3581 having been accepted up to RCPT stage. A traditional cont-conn
3582 always has a sequence number greater than one. */
3584 if (continue_hostname && continue_sequence == 1)
3586 /* sx->pending_MAIL = FALSE; */
3588 /* sx->next_addr = NULL; */
3590 for (address_item * addr = addrlist; addr; addr = addr->next)
3591 addr->transport_return = PENDING_OK;
3595 /* Initiate a message transfer. */
3597 switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))
3600 case -1: case -2: goto RESPONSE_FAILED;
3601 case -3: goto END_OFF;
3602 case -4: goto SEND_QUIT;
3603 default: goto SEND_FAILED;
3606 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3607 permanently or temporarily. We should have flushed and synced after the last
3615 for (a = sx->first_addr, cnt = 0; a && cnt < sx->max_rcpt; a = a->next, cnt++)
3616 if (a->transport_return != PENDING_OK)
3618 /*XXX could we find a better errno than 0 here? */
3619 set_errno_nohost(addrlist, 0, a->message, FAIL,
3620 testflag(a, af_pass_message), &sx->delivery_start);
3627 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3628 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3629 have a good recipient buffered up if we are pipelining. We don't want to waste
3630 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3631 are pipelining. The responses are all handled by sync_responses().
3632 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3635 if ( !(sx->peer_offered & OPTION_CHUNKING)
3636 && (sx->ok || (pipelining_active && !mua_wrapper)))
3638 int count = smtp_write_command(sx, SCMD_FLUSH, "DATA\r\n");
3640 if (count < 0) goto SEND_FAILED;
3641 switch(sync_responses(sx, count, sx->ok ? +1 : -1))
3643 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3644 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3647 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3648 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
3649 case 0: break; /* No 2xx or 5xx, but no probs */
3651 case -1: goto END_OFF; /* Timeout on RCPT */
3653 #ifndef DISABLE_PIPE_CONNECT
3654 case -5: /* TLS first-read error */
3655 case -4: HDEBUG(D_transport)
3656 debug_printf("failed reaping pipelined cmd responses\n");
3658 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3660 pipelining_active = FALSE;
3661 data_command = string_copy(big_buffer); /* Save for later error message */
3664 /* If there were no good recipients (but otherwise there have been no
3665 problems), just set ok TRUE, since we have handled address-specific errors
3666 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3667 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3668 well as body. Set the appropriate timeout value to be used for each chunk.
3669 (Haven't been able to make it work using select() for writing yet.) */
3672 && (!(sx->peer_offered & OPTION_CHUNKING) || !pipelining_active))
3674 /* Save the first address of the next batch. */
3675 sx->first_addr = sx->next_addr;
3681 transport_ctx tctx = {
3682 .u = {.fd = sx->cctx.sock}, /*XXX will this need TLS info? */
3685 .check_string = US".",
3686 .escape_string = US"..", /* Escaping strings */
3688 topt_use_crlf | topt_escape_headers
3689 | (tblock->body_only ? topt_no_headers : 0)
3690 | (tblock->headers_only ? topt_no_body : 0)
3691 | (tblock->return_path_add ? topt_add_return_path : 0)
3692 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
3693 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
3696 /* If using CHUNKING we need a callback from the generic transport
3697 support to us, for the sending of BDAT smtp commands and the reaping
3698 of responses. The callback needs a whole bunch of state so set up
3699 a transport-context structure to be passed around. */
3701 if (sx->peer_offered & OPTION_CHUNKING)
3703 tctx.check_string = tctx.escape_string = NULL;
3704 tctx.options |= topt_use_bdat;
3705 tctx.chunk_cb = smtp_chunk_cmd_callback;
3706 sx->pending_BDAT = FALSE;
3707 sx->good_RCPT = sx->ok;
3709 tctx.smtp_context = sx;
3712 tctx.options |= topt_end_dot;
3714 /* Save the first address of the next batch. */
3715 sx->first_addr = sx->next_addr;
3717 /* Responses from CHUNKING commands go in buffer. Otherwise,
3718 there has not been a response. */
3722 sigalrm_seen = FALSE;
3723 transport_write_timeout = ob->data_timeout;
3724 smtp_command = US"sending data block"; /* For error messages */
3725 DEBUG(D_transport|D_v)
3726 if (sx->peer_offered & OPTION_CHUNKING)
3727 debug_printf(" will write message using CHUNKING\n");
3729 debug_printf(" SMTP>> writing message and terminating \".\"\n");
3730 transport_count = 0;
3732 #ifndef DISABLE_DKIM
3734 # ifdef MEASURE_TIMING
3736 gettimeofday(&t0, NULL);
3738 dkim_exim_sign_init();
3739 # ifdef EXPERIMENTAL_ARC
3741 uschar * s = ob->arc_sign;
3744 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
3746 if (!f.expand_string_forcedfail)
3748 message = US"failed to expand arc_sign";
3755 /* Ask dkim code to hash the body for ARC */
3756 (void) arc_ams_setup_sign_bodyhash();
3757 ob->dkim.force_bodyhash = TRUE;
3762 # ifdef MEASURE_TIMING
3763 report_time_since(&t0, US"dkim_exim_sign_init (delta)");
3766 sx->ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
3768 sx->ok = transport_write_message(&tctx, 0);
3771 /* transport_write_message() uses write() because it is called from other
3772 places to write to non-sockets. This means that under some OS (e.g. Solaris)
3773 it can exit with "Broken pipe" as its error. This really means that the
3774 socket got closed at the far end. */
3776 transport_write_timeout = 0; /* for subsequent transports */
3778 /* Failure can either be some kind of I/O disaster (including timeout),
3779 or the failure of a transport filter or the expansion of added headers.
3780 Or, when CHUNKING, it can be a protocol-detected failure. */
3783 if (message) goto SEND_FAILED;
3784 else goto RESPONSE_FAILED;
3786 /* We used to send the terminating "." explicitly here, but because of
3787 buffering effects at both ends of TCP/IP connections, you don't gain
3788 anything by keeping it separate, so it might as well go in the final
3789 data buffer for efficiency. This is now done by setting the topt_end_dot
3792 smtp_command = US"end of data";
3794 if (sx->peer_offered & OPTION_CHUNKING && sx->cmd_count > 1)
3796 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
3797 switch(sync_responses(sx, sx->cmd_count-1, 0))
3799 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
3800 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
3803 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
3804 if (!sx->lmtp) sx->completed_addr = TRUE; /* can't tell about progress yet */
3805 case 0: break; /* No 2xx or 5xx, but no probs */
3807 case -1: goto END_OFF; /* Timeout on RCPT */
3809 #ifndef DISABLE_PIPE_CONNECT
3810 case -5: /* TLS first-read error */
3811 case -4: HDEBUG(D_transport)
3812 debug_printf("failed reaping pipelined cmd responses\n");
3814 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3818 #ifndef DISABLE_PRDR
3819 /* For PRDR we optionally get a partial-responses warning followed by the
3820 individual responses, before going on with the overall response. If we don't
3821 get the warning then deal with per non-PRDR. */
3825 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '3', ob->final_timeout);
3826 if (!sx->ok && errno == 0) switch(sx->buffer[0])
3828 case '2': sx->prdr_active = FALSE;
3831 case '4': errno = ERRNO_DATA4XX;
3832 addrlist->more_errno |=
3833 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3840 /* For non-PRDR SMTP, we now read a single response that applies to the
3841 whole message. If it is OK, then all the addresses have been delivered. */
3845 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3847 if (!sx->ok && errno == 0 && sx->buffer[0] == '4')
3849 errno = ERRNO_DATA4XX;
3850 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3854 /* For LMTP, we get back a response for every RCPT command that we sent;
3855 some may be accepted and some rejected. For those that get a response, their
3856 status is fixed; any that are accepted have been handed over, even if later
3857 responses crash - at least, that's how I read RFC 2033.
3859 If all went well, mark the recipient addresses as completed, record which
3860 host/IPaddress they were delivered to, and cut out RSET when sending another
3861 message down the same channel. Write the completed addresses to the journal
3862 now so that they are recorded in case there is a crash of hardware or
3863 software before the spool gets updated. Also record the final SMTP
3864 confirmation if needed (for SMTP only). */
3869 struct timeval delivery_time;
3871 uschar * conf = NULL;
3873 timesince(&delivery_time, &sx->delivery_start);
3874 sx->send_rset = FALSE;
3875 pipelining_active = FALSE;
3877 /* Set up confirmation if needed - applies only to SMTP */
3880 #ifdef DISABLE_EVENT
3881 LOGGING(smtp_confirmation) &&
3886 const uschar *s = string_printing(sx->buffer);
3887 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3888 conf = (s == sx->buffer)? US string_copy(s) : US s;
3891 /* Process all transported addresses - for LMTP or PRDR, read a status for
3894 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
3896 if (addr->transport_return != PENDING_OK) continue;
3898 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3899 remaining addresses. Otherwise, it's a return code for just the one
3900 address. For temporary errors, add a retry item for the address so that
3901 it doesn't get tried again too soon. */
3903 #ifndef DISABLE_PRDR
3904 if (sx->lmtp || sx->prdr_active)
3909 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3912 if (errno != 0 || sx->buffer[0] == 0) goto RESPONSE_FAILED;
3913 addr->message = string_sprintf(
3914 #ifndef DISABLE_PRDR
3915 "%s error after %s: %s", sx->prdr_active ? "PRDR":"LMTP",
3917 "LMTP error after %s: %s",
3919 data_command, string_printing(sx->buffer));
3920 setflag(addr, af_pass_message); /* Allow message to go to user */
3921 if (sx->buffer[0] == '5')
3922 addr->transport_return = FAIL;
3925 errno = ERRNO_DATA4XX;
3926 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3927 addr->transport_return = DEFER;
3928 #ifndef DISABLE_PRDR
3929 if (!sx->prdr_active)
3931 retry_add_item(addr, addr->address_retry_key, 0);
3935 sx->completed_addr = TRUE; /* NOW we can set this flag */
3936 if (LOGGING(smtp_confirmation))
3938 const uschar *s = string_printing(sx->buffer);
3939 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3940 conf = (s == sx->buffer) ? US string_copy(s) : US s;
3944 /* SMTP, or success return from LMTP for this address. Pass back the
3945 actual host that was used. */
3947 addr->transport_return = OK;
3948 addr->host_used = host;
3949 addr->delivery_time = delivery_time;
3950 addr->special_action = flag;
3951 addr->message = conf;
3953 if (tcp_out_fastopen)
3955 setflag(addr, af_tcp_fastopen_conn);
3956 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
3957 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
3959 if (sx->pipelining_used) setflag(addr, af_pipelining);
3960 #ifndef DISABLE_PIPE_CONNECT
3961 if (sx->early_pipe_active) setflag(addr, af_early_pipe);
3963 #ifndef DISABLE_PRDR
3964 if (sx->prdr_active) setflag(addr, af_prdr_used);
3966 if (sx->peer_offered & OPTION_CHUNKING) setflag(addr, af_chunking_used);
3969 #ifndef DISABLE_PRDR
3970 if (!sx->prdr_active)
3973 /* Update the journal. For homonymic addresses, use the base address plus
3974 the transport name. See lots of comments in deliver.c about the reasons
3975 for the complications when homonyms are involved. Just carry on after
3976 write error, as it may prove possible to update the spool file later. */
3978 if (testflag(addr, af_homonym))
3979 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3981 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
3983 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx->buffer);
3984 len = Ustrlen(CS sx->buffer);
3985 if (write(journal_fd, sx->buffer, len) != len)
3986 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3987 "%s: %s", sx->buffer, strerror(errno));
3991 #ifndef DISABLE_PRDR
3992 if (sx->prdr_active)
3994 const uschar * overall_message;
3996 /* PRDR - get the final, overall response. For any non-success
3997 upgrade all the address statuses. */
3999 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4003 if(errno == 0 && sx->buffer[0] == '4')
4005 errno = ERRNO_DATA4XX;
4006 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4008 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4009 if (sx->buffer[0] == '5' || addr->transport_return == OK)
4010 addr->transport_return = PENDING_OK; /* allow set_errno action */
4011 goto RESPONSE_FAILED;
4014 /* Append the overall response to the individual PRDR response for logging
4015 and update the journal, or setup retry. */
4017 overall_message = string_printing(sx->buffer);
4018 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4019 if (addr->transport_return == OK)
4020 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
4022 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4023 if (addr->transport_return == OK)
4025 if (testflag(addr, af_homonym))
4026 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4028 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4030 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx->buffer);
4031 len = Ustrlen(CS sx->buffer);
4032 if (write(journal_fd, sx->buffer, len) != len)
4033 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4034 "%s: %s", sx->buffer, strerror(errno));
4036 else if (addr->transport_return == DEFER)
4037 retry_add_item(addr, addr->address_retry_key, -2);
4041 /* Ensure the journal file is pushed out to disk. */
4043 if (EXIMfsync(journal_fd) < 0)
4044 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
4050 /* Handle general (not specific to one address) failures here. The value of ok
4051 is used to skip over this code on the falling through case. A timeout causes a
4052 deferral. Other errors may defer or fail according to the response code, and
4053 may set up a special errno value, e.g. after connection chopped, which is
4054 assumed if errno == 0 and there is no text in the buffer. If control reaches
4055 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
4056 the problem is not related to this specific message. */
4061 uschar * set_message;
4067 sx->send_quit = check_response(host, &save_errno, addrlist->more_errno,
4068 sx->buffer, &code, &message, &pass_message);
4076 message = string_sprintf("send() to %s [%s] failed: %s",
4077 host->name, host->address, message ? message : US strerror(save_errno));
4078 sx->send_quit = FALSE;
4086 sx->ok = FALSE; /* For when reached by GOTO */
4087 set_message = message;
4089 /* We want to handle timeouts after MAIL or "." and loss of connection after
4090 "." specially. They can indicate a problem with the sender address or with
4091 the contents of the message rather than a real error on the connection. These
4092 cases are treated in the same way as a 4xx response. This next bit of code
4093 does the classification. */
4100 message_error = TRUE;
4104 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4105 Ustrncmp(smtp_command,"end ",4) == 0;
4108 case ERRNO_SMTPCLOSED:
4109 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4113 message_error = FALSE;
4117 /* Handle the cases that are treated as message errors. These are:
4119 (a) negative response or timeout after MAIL
4120 (b) negative response after DATA
4121 (c) negative response or timeout or dropped connection after "."
4122 (d) utf8 support required and not offered
4124 It won't be a negative response or timeout after RCPT, as that is dealt
4125 with separately above. The action in all cases is to set an appropriate
4126 error code for all the addresses, but to leave yield set to OK because the
4127 host itself has not failed. Of course, it might in practice have failed
4128 when we've had a timeout, but if so, we'll discover that at the next
4129 delivery attempt. For a temporary error, set the message_defer flag, and
4130 write to the logs for information if this is not the last host. The error
4131 for the last host will be logged as part of the address's log line. */
4135 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4137 /* If there's an errno, the message contains just the identity of
4142 else /* Anything other than 5 is treated as temporary */
4146 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4148 write_logs(host, message, sx->first_addr ? sx->first_addr->basic_errno : 0);
4150 *message_defer = TRUE;
4153 DEBUG(D_transport) if (sx->cctx.sock >= 0)
4156 if (ioctl(sx->cctx.sock, TIOCOUTQ, &n) == 0)
4157 debug_printf("%d bytes remain in socket output buffer\n", n);
4161 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4162 ".", or some other transportation error. We defer all addresses and yield
4163 DEFER, except for the case of failed add_headers expansion, or a transport
4164 filter failure, when the yield should be ERROR, to stop it trying other
4169 #ifndef DISABLE_PIPE_CONNECT
4170 /* If we were early-pipelinng and the actual EHLO response did not match
4171 the cached value we assumed, we could have detected it and passed a
4172 custom errno through to here. It would be nice to RSET and retry right
4173 away, but to reliably do that we eould need an extra synch point before
4174 we committed to data and that would discard half the gained roundrips.
4175 Or we could summarily drop the TCP connection. but that is also ugly.
4176 Instead, we ignore the possibility (having freshened the cache) and rely
4177 on the server telling us with a nonmessage error if we have tried to
4178 do something it no longer supports. */
4181 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4182 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4186 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host,
4187 #ifdef EXPERIMENTAL_DSN_INFO
4188 sx->smtp_greeting, sx->helo_response,
4190 &sx->delivery_start);
4193 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4194 SMTP session tidily. However, if there were too many addresses to send in one
4195 message (indicated by first_addr being non-NULL) we want to carry on with the
4196 rest of them. Also, it is desirable to send more than one message down the SMTP
4197 connection if there are several waiting, provided we haven't already sent so
4198 many as to hit the configured limit. The function transport_check_waiting looks
4199 for a waiting message and returns its id. Then transport_pass_socket tries to
4200 set up a continued delivery by passing the socket on to another process. The
4201 variable send_rset is FALSE if a message has just been successfully transferred.
4203 If we are already sending down a continued channel, there may be further
4204 addresses not yet delivered that are aimed at the same host, but which have not
4205 been passed in this run of the transport. In this case, continue_more will be
4206 true, and all we should do is send RSET if necessary, and return, leaving the
4209 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4210 do not want to continue with other messages down the same channel, because that
4211 can lead to looping between two or more messages, all with the same,
4212 temporarily failing address(es). [The retry information isn't updated yet, so
4213 new processes keep on trying.] We probably also don't want to try more of this
4214 message's addresses either.
4216 If we have started a TLS session, we have to end it before passing the
4217 connection to a new process. However, not all servers can handle this (Exim
4218 can), so we do not pass such a connection on if the host matches
4219 hosts_nopass_tls. */
4222 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4223 "yield=%d first_address is %sNULL\n", sx->ok, sx->send_quit,
4224 sx->send_rset, f.continue_more, yield, sx->first_addr ? "not " : "");
4226 if (sx->completed_addr && sx->ok && sx->send_quit)
4228 smtp_compare_t t_compare;
4230 t_compare.tblock = tblock;
4231 t_compare.current_sender_address = sender_address;
4233 if ( sx->first_addr != NULL /* more addrs for this message */
4234 || f.continue_more /* more addrs for coninued-host */
4237 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4238 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4242 transport_check_waiting(tblock->name, host->name,
4243 tblock->connection_max_messages, new_message_id,
4244 (oicf)smtp_are_same_identities, (void*)&t_compare)
4251 if (! (sx->ok = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4253 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
4254 host->address, strerror(errno));
4255 sx->send_quit = FALSE;
4257 else if (! (sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4258 '2', ob->command_timeout)))
4261 sx->send_quit = check_response(host, &errno, 0, sx->buffer, &code, &msg,
4265 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4266 host->name, host->address, msg);
4270 /* Either RSET was not needed, or it succeeded */
4277 int socket_fd = sx->cctx.sock;
4280 if (sx->first_addr != NULL) /* More addresses still to be sent */
4281 { /* for this message */
4282 continue_sequence++; /* Causes * in logging */
4283 pipelining_active = sx->pipelining_used; /* was cleared at DATA */
4287 /* Unless caller said it already has more messages listed for this host,
4288 pass the connection on to a new Exim process (below, the call to
4289 transport_pass_socket). If the caller has more ready, just return with
4290 the connection still open. */
4293 if (tls_out.active.sock >= 0)
4294 if ( f.continue_more
4295 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4297 /* Before passing the socket on, or returning to caller with it still
4298 open, we must shut down TLS. Not all MTAs allow for the continuation
4299 of the SMTP session when TLS is shut down. We test for this by sending
4300 a new EHLO. If we don't get a good response, we don't attempt to pass
4303 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4304 sx->cctx.tls_ctx = NULL;
4305 tls_out.active.sock = -1;
4306 smtp_peer_options = smtp_peer_options_wrap;
4308 && smtp_write_command(sx, SCMD_FLUSH, "EHLO %s\r\n", sx->helo_data)
4310 && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4311 '2', ob->command_timeout);
4313 if (sx->ok && f.continue_more)
4314 goto TIDYUP; /* More addresses for another run */
4318 /* Set up a pipe for proxying TLS for the new transport process */
4320 smtp_peer_options |= OPTION_TLS;
4321 if ((sx->ok = socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4324 set_errno(sx->first_addr, errno, US"internal allocation problem",
4326 # ifdef EXPERIMENTAL_DSN_INFO
4327 sx->smtp_greeting, sx->helo_response,
4329 &sx->delivery_start);
4333 if (f.continue_more)
4334 goto TIDYUP; /* More addresses for another run */
4336 /* If the socket is successfully passed, we mustn't send QUIT (or
4337 indeed anything!) from here. */
4339 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4340 propagate it from the initial
4342 if (sx->ok && transport_pass_socket(tblock->name, host->name,
4343 host->address, new_message_id, socket_fd))
4345 sx->send_quit = FALSE;
4347 /* We have passed the client socket to a fresh transport process.
4348 If TLS is still active, we need to proxy it for the transport we
4349 just passed the baton to. Fork a child to to do it, and return to
4350 get logging done asap. Which way to place the work makes assumptions
4351 about post-fork prioritisation which may not hold on all platforms. */
4353 if (tls_out.active.sock >= 0)
4355 int pid = exim_fork(US"tls-proxy-interproc");
4356 if (pid == 0) /* child; fork again to disconnect totally */
4358 /* does not return */
4359 smtp_proxy_tls(sx->cctx.tls_ctx, sx->buffer, sizeof(sx->buffer), pfd,
4360 ob->command_timeout);
4363 if (pid > 0) /* parent */
4366 /* tidy the inter-proc to disconn the proxy proc */
4367 waitpid(pid, NULL, 0);
4368 tls_close(sx->cctx.tls_ctx, TLS_NO_SHUTDOWN);
4369 sx->cctx.tls_ctx = NULL;
4370 (void)close(sx->cctx.sock);
4372 continue_transport = NULL;
4373 continue_hostname = NULL;
4376 log_write(0, LOG_PANIC_DIE, "fork failed");
4382 /* If RSET failed and there are addresses left, they get deferred. */
4384 set_errno(sx->first_addr, errno, msg, DEFER, FALSE, host,
4385 #ifdef EXPERIMENTAL_DSN_INFO
4386 sx->smtp_greeting, sx->helo_response,
4388 &sx->delivery_start);
4392 /* End off tidily with QUIT unless the connection has died or the socket has
4393 been passed to another process. */
4397 /* Use _MORE to get QUIT in FIN segment */
4398 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4403 # ifdef EXIM_TCP_CORK
4404 if (sx->cctx.tls_ctx) /* Use _CORK to get TLS Close Notify in FIN segment */
4405 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4408 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
4409 sx->cctx.tls_ctx = NULL;
4412 /* Close the socket, and return the appropriate value, first setting
4413 works because the NULL setting is passed back to the calling process, and
4414 remote_max_parallel is forced to 1 when delivering over an existing connection,
4416 If all went well and continue_more is set, we shouldn't actually get here if
4417 there are further addresses, as the return above will be taken. However,
4418 writing RSET might have failed, or there may be other addresses whose hosts are
4419 specified in the transports, and therefore not visible at top level, in which
4420 case continue_more won't get set. */
4422 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4425 /* This flushes data queued in the socket, being the QUIT and any TLS Close,
4426 sending them along with the client FIN flag. Us (we hope) sending FIN first
4427 means we (client) take the TIME_WAIT state, so the server (which likely has a
4428 higher connection rate) does no have to. */
4430 shutdown(sx->cctx.sock, SHUT_WR);
4432 /* Wait for (we hope) ack of our QUIT, and a server FIN. Discard any data
4433 received, then discard the socket. Any packet received after then, or receive
4434 data still in the socket, will get a RST - hence the pause/drain. */
4437 testharness_pause_ms(200);
4438 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4439 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
4440 i--; /* drain socket */
4442 (void)close(sx->cctx.sock);
4444 #ifndef DISABLE_EVENT
4445 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
4451 sx->first_addr = NULL;
4452 for (address_item * a = sx->addrlist->next; a; a = a->next)
4453 if (a->transport_return == DANE)
4455 a->transport_return = PENDING_DEFER;
4456 if (!sx->first_addr)
4458 /* Remember the new start-point in the addrlist, for smtp_setup_conn()
4459 to get the domain string for SNI */
4462 DEBUG(D_transport) debug_printf("DANE: go-around for %s\n", a->domain);
4469 continue_transport = NULL;
4470 continue_hostname = NULL;
4475 if (dane_held) for (address_item * a = sx->addrlist->next; a; a = a->next)
4476 if (a->transport_return == DANE)
4477 a->transport_return = PENDING_DEFER;
4485 /*************************************************
4486 * Closedown entry point *
4487 *************************************************/
4489 /* This function is called when exim is passed an open smtp channel
4490 from another incarnation, but the message which it has been asked
4491 to deliver no longer exists. The channel is on stdin.
4493 We might do fancy things like looking for another message to send down
4494 the channel, but if the one we sought has gone, it has probably been
4495 delivered by some other process that itself will seek further messages,
4496 so just close down our connection.
4498 Argument: pointer to the transport instance block
4503 smtp_transport_closedown(transport_instance *tblock)
4505 smtp_transport_options_block * ob = SOB tblock->options_block;
4506 client_conn_ctx cctx;
4509 uschar inbuffer[4096];
4510 uschar outbuffer[16];
4512 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
4513 cctx.sock = fileno(stdin);
4514 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
4516 sx.inblock.cctx = &cctx;
4517 sx.inblock.buffer = inbuffer;
4518 sx.inblock.buffersize = sizeof(inbuffer);
4519 sx.inblock.ptr = inbuffer;
4520 sx.inblock.ptrend = inbuffer;
4522 sx.outblock.cctx = &cctx;
4523 sx.outblock.buffersize = sizeof(outbuffer);
4524 sx.outblock.buffer = outbuffer;
4525 sx.outblock.ptr = outbuffer;
4526 sx.outblock.cmd_count = 0;
4527 sx.outblock.authenticating = FALSE;
4529 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
4530 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
4531 (void)close(cctx.sock);
4536 /*************************************************
4537 * Prepare addresses for delivery *
4538 *************************************************/
4540 /* This function is called to flush out error settings from previous delivery
4541 attempts to other hosts. It also records whether we got here via an MX record
4542 or not in the more_errno field of the address. We are interested only in
4543 addresses that are still marked DEFER - others may have got delivered to a
4544 previously considered IP address. Set their status to PENDING_DEFER to indicate
4545 which ones are relevant this time.
4548 addrlist the list of addresses
4549 host the host we are delivering to
4551 Returns: the first address for this delivery
4554 static address_item *
4555 prepare_addresses(address_item *addrlist, host_item *host)
4557 address_item *first_addr = NULL;
4558 for (address_item * addr = addrlist; addr; addr = addr->next)
4559 if (addr->transport_return == DEFER)
4561 if (!first_addr) first_addr = addr;
4562 addr->transport_return = PENDING_DEFER;
4563 addr->basic_errno = 0;
4564 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
4565 addr->message = NULL;
4567 addr->cipher = NULL;
4568 addr->ourcert = NULL;
4569 addr->peercert = NULL;
4570 addr->peerdn = NULL;
4571 addr->ocsp = OCSP_NOT_REQ;
4572 addr->tlsver = NULL;
4574 #ifdef EXPERIMENTAL_DSN_INFO
4575 addr->smtp_greeting = NULL;
4576 addr->helo_response = NULL;
4584 /*************************************************
4585 * Main entry point *
4586 *************************************************/
4588 /* See local README for interface details. As this is a remote transport, it is
4589 given a chain of addresses to be delivered in one connection, if possible. It
4590 always returns TRUE, indicating that each address has its own independent
4591 status set, except if there is a setting up problem, in which case it returns
4595 smtp_transport_entry(
4596 transport_instance *tblock, /* data for this instantiation */
4597 address_item *addrlist) /* addresses we are working on */
4600 int hosts_defer = 0;
4602 int hosts_looked_up = 0;
4603 int hosts_retry = 0;
4604 int hosts_serial = 0;
4605 int hosts_total = 0;
4606 int total_hosts_tried = 0;
4607 BOOL expired = TRUE;
4608 uschar *expanded_hosts = NULL;
4610 uschar *tid = string_sprintf("%s transport", tblock->name);
4611 smtp_transport_options_block *ob = SOB tblock->options_block;
4612 host_item *hostlist = addrlist->host_list;
4613 host_item *host = NULL;
4617 debug_printf("%s transport entered\n", tblock->name);
4618 for (address_item * addr = addrlist; addr; addr = addr->next)
4619 debug_printf(" %s\n", addr->address);
4622 debug_printf("hostlist:\n");
4623 for (host_item * host = hostlist; host; host = host->next)
4624 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
4626 if (continue_hostname)
4627 debug_printf("already connected to %s [%s] (on fd %d)\n",
4628 continue_hostname, continue_host_address,
4629 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
4632 /* Check the restrictions on line length */
4634 if (max_received_linelength > ob->message_linelength_limit)
4637 gettimeofday(&now, NULL);
4639 for (address_item * addr = addrlist; addr; addr = addr->next)
4640 if (addr->transport_return == DEFER)
4641 addr->transport_return = PENDING_DEFER;
4643 set_errno_nohost(addrlist, ERRNO_SMTPFORMAT,
4644 US"message has lines too long for transport", FAIL, TRUE, &now);
4648 /* Set the flag requesting that these hosts be added to the waiting
4649 database if the delivery fails temporarily or if we are running with
4650 queue_smtp or a 2-stage queue run. This gets unset for certain
4651 kinds of error, typically those that are specific to the message. */
4653 update_waiting = TRUE;
4655 /* If a host list is not defined for the addresses - they must all have the
4656 same one in order to be passed to a single transport - or if the transport has
4657 a host list with hosts_override set, use the host list supplied with the
4658 transport. It is an error for this not to exist. */
4660 if (!hostlist || (ob->hosts_override && ob->hosts))
4664 addrlist->message = string_sprintf("%s transport called with no hosts set",
4666 addrlist->transport_return = PANIC;
4667 return FALSE; /* Only top address has status */
4670 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
4673 /* If the transport's host list contains no '$' characters, and we are not
4674 randomizing, it is fixed and therefore a chain of hosts can be built once
4675 and for all, and remembered for subsequent use by other calls to this
4676 transport. If, on the other hand, the host list does contain '$', or we are
4677 randomizing its order, we have to rebuild it each time. In the fixed case,
4678 as the hosts string will never be used again, it doesn't matter that we
4679 replace all the : characters with zeros. */
4683 uschar *s = ob->hosts;
4685 if (Ustrchr(s, '$') != NULL)
4687 if (!(expanded_hosts = expand_string(s)))
4689 addrlist->message = string_sprintf("failed to expand list of hosts "
4690 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
4691 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
4692 return FALSE; /* Only top address has status */
4694 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
4695 "\"%s\"\n", s, expanded_hosts);
4699 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
4703 log_write(0, LOG_MAIN|LOG_PANIC,
4704 "attempt to use tainted host list '%s' from '%s' in transport %s",
4705 s, ob->hosts, tblock->name);
4706 /* Avoid leaking info to an attacker */
4707 addrlist->message = US"internal configuration error";
4708 addrlist->transport_return = PANIC;
4712 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
4714 /* Check that the expansion yielded something useful. */
4718 string_sprintf("%s transport has empty hosts setting", tblock->name);
4719 addrlist->transport_return = PANIC;
4720 return FALSE; /* Only top address has status */
4723 /* If there was no expansion of hosts, save the host list for
4726 if (!expanded_hosts) ob->hostlist = hostlist;
4729 /* This is not the first time this transport has been run in this delivery;
4730 the host list was built previously. */
4733 hostlist = ob->hostlist;
4736 /* The host list was supplied with the address. If hosts_randomize is set, we
4737 must sort it into a random order if it did not come from MX records and has not
4738 already been randomized (but don't bother if continuing down an existing
4741 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
4743 host_item *newlist = NULL;
4746 host_item *h = hostlist;
4747 hostlist = hostlist->next;
4749 h->sort_key = random_number(100);
4756 else if (h->sort_key < newlist->sort_key)
4763 host_item *hh = newlist;
4766 if (h->sort_key < hh->next->sort_key) break;
4774 hostlist = addrlist->host_list = newlist;
4777 /* Sort out the default port. */
4779 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
4781 /* For each host-plus-IP-address on the list:
4783 . If this is a continued delivery and the host isn't the one with the
4784 current connection, skip.
4786 . If the status is unusable (i.e. previously failed or retry checked), skip.
4788 . If no IP address set, get the address, either by turning the name into
4789 an address, calling gethostbyname if gethostbyname is on, or by calling
4790 the DNS. The DNS may yield multiple addresses, in which case insert the
4791 extra ones into the list.
4793 . Get the retry data if not previously obtained for this address and set the
4794 field which remembers the state of this address. Skip if the retry time is
4795 not reached. If not, remember whether retry data was found. The retry string
4796 contains both the name and the IP address.
4798 . Scan the list of addresses and mark those whose status is DEFER as
4799 PENDING_DEFER. These are the only ones that will be processed in this cycle
4802 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
4803 Some addresses may be successfully delivered, others may fail, and yet
4804 others may get temporary errors and so get marked DEFER.
4806 . The return from the delivery attempt is OK if a connection was made and a
4807 valid SMTP dialogue was completed. Otherwise it is DEFER.
4809 . If OK, add a "remove" retry item for this host/IPaddress, if any.
4811 . If fail to connect, or other defer state, add a retry item.
4813 . If there are any addresses whose status is still DEFER, carry on to the
4814 next host/IPaddress, unless we have tried the number of hosts given
4815 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
4816 there is some fancy logic for hosts_max_try that means its limit can be
4817 overstepped in some circumstances.
4819 If we get to the end of the list, all hosts have deferred at least one address,
4820 or not reached their retry times. If delay_after_cutoff is unset, it requests a
4821 delivery attempt to those hosts whose last try was before the arrival time of
4822 the current message. To cope with this, we have to go round the loop a second
4823 time. After that, set the status and error data for any addresses that haven't
4824 had it set already. */
4826 for (int cutoff_retry = 0;
4827 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
4830 host_item *nexthost = NULL;
4831 int unexpired_hosts_tried = 0;
4832 BOOL continue_host_tried = FALSE;
4834 retry_non_continued:
4835 for (host = hostlist;
4837 && unexpired_hosts_tried < ob->hosts_max_try
4838 && total_hosts_tried < ob->hosts_max_try_hardlimit;
4843 BOOL host_is_expired = FALSE;
4844 BOOL message_defer = FALSE;
4845 BOOL some_deferred = FALSE;
4846 address_item *first_addr = NULL;
4847 uschar *interface = NULL;
4848 uschar *retry_host_key = NULL;
4849 uschar *retry_message_key = NULL;
4850 uschar *serialize_key = NULL;
4852 /* Default next host is next host. :-) But this can vary if the
4853 hosts_max_try limit is hit (see below). It may also be reset if a host
4854 address is looked up here (in case the host was multihomed). */
4856 nexthost = host->next;
4858 /* If the address hasn't yet been obtained from the host name, look it up
4859 now, unless the host is already marked as unusable. If it is marked as
4860 unusable, it means that the router was unable to find its IP address (in
4861 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
4862 the lookup failed last time. We don't get this far if *all* MX records
4863 point to non-existent hosts; that is treated as a hard error.
4865 We can just skip this host entirely. When the hosts came from the router,
4866 the address will timeout based on the other host(s); when the address is
4867 looked up below, there is an explicit retry record added.
4869 Note that we mustn't skip unusable hosts if the address is not unset; they
4870 may be needed as expired hosts on the 2nd time round the cutoff loop. */
4874 int new_port, flags;
4876 if (host->status >= hstatus_unusable)
4878 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
4883 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
4885 /* The host name is permitted to have an attached port. Find it, and
4886 strip it from the name. Just remember it for now. */
4888 new_port = host_item_get_port(host);
4890 /* Count hosts looked up */
4894 /* Find by name if so configured, or if it's an IP address. We don't
4895 just copy the IP address, because we need the test-for-local to happen. */
4897 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
4898 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
4899 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
4901 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
4902 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
4904 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
4905 &ob->dnssec, /* domains for request/require */
4908 /* Update the host (and any additional blocks, resulting from
4909 multihoming) with a host-specific port, if any. */
4911 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
4913 /* Failure to find the host at this time (usually DNS temporary failure)
4914 is really a kind of routing failure rather than a transport failure.
4915 Therefore we add a retry item of the routing kind, not to stop us trying
4916 to look this name up here again, but to ensure the address gets timed
4917 out if the failures go on long enough. A complete failure at this point
4918 commonly points to a configuration error, but the best action is still
4919 to carry on for the next host. */
4921 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
4923 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
4925 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
4926 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
4927 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
4928 host->status = hstatus_unusable;
4930 for (address_item * addr = addrlist; addr; addr = addr->next)
4932 if (addr->transport_return != DEFER) continue;
4933 addr->basic_errno = ERRNO_UNKNOWNHOST;
4934 addr->message = string_sprintf(
4935 rc == HOST_FIND_SECURITY
4936 ? "lookup of IP address for %s was insecure"
4937 : "failed to lookup IP address for %s",
4943 /* If the host is actually the local host, we may have a problem, or
4944 there may be some cunning configuration going on. In the problem case,
4945 log things and give up. The default transport status is already DEFER. */
4947 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
4949 for (address_item * addr = addrlist; addr; addr = addr->next)
4951 addr->basic_errno = ERRNO_HOST_IS_LOCAL;
4952 addr->message = string_sprintf("%s transport found host %s to be "
4953 "local", tblock->name, host->name);
4957 } /* End of block for IP address lookup */
4959 /* If this is a continued delivery, we are interested only in the host
4960 which matches the name of the existing open channel. The check is put
4961 here after the local host lookup, in case the name gets expanded as a
4962 result of the lookup. Set expired FALSE, to save the outer loop executing
4965 if (continue_hostname)
4966 if ( Ustrcmp(continue_hostname, host->name) != 0
4967 || Ustrcmp(continue_host_address, host->address) != 0
4971 continue; /* With next host */
4974 continue_host_tried = TRUE;
4976 /* Reset the default next host in case a multihomed host whose addresses
4977 are not looked up till just above added to the host list. */
4979 nexthost = host->next;
4981 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
4982 domain is in queue_smtp_domains, we don't actually want to attempt any
4983 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
4984 there is a lookup defer in queue_smtp_domains, proceed as if the domain
4985 were not in it. We don't want to hold up all SMTP deliveries! Except when
4986 doing a two-stage queue run, don't do this if forcing. */
4988 if ( (!f.deliver_force || f.queue_2stage)
4990 || match_isinlist(addrlist->domain,
4991 CUSS &queue_smtp_domains, 0,
4992 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK)
4995 DEBUG(D_transport) debug_printf("first-pass routing only\n");
4997 for (address_item * addr = addrlist; addr; addr = addr->next)
4998 if (addr->transport_return == DEFER)
4999 addr->message = US"first-pass only routing due to -odqs, "
5000 "queue_smtp_domains or control=queue";
5001 continue; /* With next host */
5004 /* Count hosts being considered - purely for an intelligent comment
5005 if none are usable. */
5009 /* Set $host and $host address now in case they are needed for the
5010 interface expansion or the serialize_hosts check; they remain set if an
5011 actual delivery happens. */
5013 deliver_host = host->name;
5014 deliver_host_address = host->address;
5015 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
5016 : host->dnssec == DS_NO ? US"no"
5019 /* Set up a string for adding to the retry key if the port number is not
5020 the standard SMTP port. A host may have its own port setting that overrides
5023 pistring = string_sprintf(":%d", host->port == PORT_NONE
5024 ? defport : host->port);
5025 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
5027 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
5028 string is set, even if constant (as different transports can have different
5029 constant settings), we must add it to the key that is used for retries,
5030 because connections to the same host from a different interface should be
5031 treated separately. */
5033 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
5035 uschar * s = ob->interface;
5038 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
5040 pistring = string_sprintf("%s/%s", pistring, interface);
5044 /* The first time round the outer loop, check the status of the host by
5045 inspecting the retry data. The second time round, we are interested only
5046 in expired hosts that haven't been tried since this message arrived. */
5048 if (cutoff_retry == 0)
5051 /* Ensure the status of the address is set by checking retry data if
5052 necessary. There may be host-specific retry data (applicable to all
5053 messages) and also data for retries of a specific message at this host.
5054 If either of these retry records are actually read, the keys used are
5055 returned to save recomputing them later. */
5057 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5058 US"retry_include_ip_address", ob->retry_include_ip_address,
5059 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5060 continue; /* with next host */
5062 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
5063 incl_ip, &retry_host_key, &retry_message_key);
5065 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
5066 host->address ? host->address : US"", pistring,
5067 host->status == hstatus_usable ? "usable"
5068 : host->status == hstatus_unusable ? "unusable"
5069 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
5071 /* Skip this address if not usable at this time, noting if it wasn't
5072 actually expired, both locally and in the address. */
5074 switch (host->status)
5076 case hstatus_unusable:
5078 setflag(addrlist, af_retry_skipped);
5081 case hstatus_unusable_expired:
5084 case hwhy_retry: hosts_retry++; break;
5085 case hwhy_failed: hosts_fail++; break;
5087 case hwhy_deferred: hosts_defer++; break;
5090 /* If there was a retry message key, implying that previously there
5091 was a message-specific defer, we don't want to update the list of
5092 messages waiting for these hosts. */
5094 if (retry_message_key) update_waiting = FALSE;
5095 continue; /* With the next host or IP address */
5099 /* Second time round the loop: if the address is set but expired, and
5100 the message is newer than the last try, let it through. */
5105 || host->status != hstatus_unusable_expired
5106 || host->last_try > received_time.tv_sec)
5108 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
5109 host->name, host->address, pistring);
5110 host_is_expired = TRUE;
5113 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
5114 it remains TRUE only if all hosts are expired and none are actually tried.
5119 /* If this host is listed as one to which access must be serialized,
5120 see if another Exim process has a connection to it, and if so, skip
5121 this host. If not, update the database to record our connection to it
5122 and remember this for later deletion. Do not do any of this if we are
5123 sending the message down a pre-existing connection. */
5125 if ( !continue_hostname
5126 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
5128 serialize_key = string_sprintf("host-serialize-%s", host->name);
5129 if (!enq_start(serialize_key, 1))
5132 debug_printf("skipping host %s because another Exim process "
5133 "is connected to it\n", host->name);
5139 /* OK, we have an IP address that is not waiting for its retry time to
5140 arrive (it might be expired) OR (second time round the loop) we have an
5141 expired host that hasn't been tried since the message arrived. Have a go
5142 at delivering the message to it. First prepare the addresses by flushing
5143 out the result of previous attempts, and finding the first address that
5144 is still to be delivered. */
5146 first_addr = prepare_addresses(addrlist, host);
5148 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5149 message_id, host->name, host->address, addrlist->address,
5150 addrlist->next ? ", ..." : "");
5152 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5153 message_id, host->name, host->address, pistring, addrlist->address,
5154 addrlist->next ? ", ..." : "");
5156 /* This is not for real; don't do the delivery. If there are
5157 any remaining hosts, list them. */
5162 gettimeofday(&now, NULL);
5163 set_errno_nohost(addrlist, 0, NULL, OK, FALSE, &now);
5164 for (address_item * addr = addrlist; addr; addr = addr->next)
5166 addr->host_used = host;
5167 addr->special_action = '*';
5168 addr->message = US"delivery bypassed by -N option";
5172 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5173 "*** host and remaining hosts:\n", tblock->name);
5174 for (host_item * host2 = host; host2; host2 = host2->next)
5175 debug_printf(" %s [%s]\n", host2->name,
5176 host2->address ? host2->address : US"unset");
5181 /* This is for real. If the host is expired, we don't count it for
5182 hosts_max_retry. This ensures that all hosts must expire before an address
5183 is timed out, unless hosts_max_try_hardlimit (which protects against
5184 lunatic DNS configurations) is reached.
5186 If the host is not expired and we are about to hit the hosts_max_retry
5187 limit, check to see if there is a subsequent hosts with a different MX
5188 value. If so, make that the next host, and don't count this one. This is a
5189 heuristic to make sure that different MXs do get tried. With a normal kind
5190 of retry rule, they would get tried anyway when the earlier hosts were
5191 delayed, but if the domain has a "retry every time" type of rule - as is
5192 often used for the the very large ISPs, that won't happen. */
5197 /* Make a copy of the host if it is local to this invocation
5198 of the transport. */
5202 thost = store_get(sizeof(host_item), FALSE);
5204 thost->name = string_copy(host->name);
5205 thost->address = string_copy(host->address);
5210 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5213 debug_printf("hosts_max_try limit reached with this host\n");
5214 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5217 unexpired_hosts_tried--;
5218 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5219 "and will be tried\n");
5224 /* Attempt the delivery. */
5226 total_hosts_tried++;
5227 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5228 &message_defer, FALSE);
5231 OK => connection made, each address contains its result;
5232 message_defer is set for message-specific defers (when all
5233 recipients are marked defer)
5234 DEFER => there was a non-message-specific delivery problem;
5235 ERROR => there was a problem setting up the arguments for a filter,
5236 or there was a problem with expanding added headers
5239 /* If the result is not OK, there was a non-message-specific problem.
5240 If the result is DEFER, we need to write to the logs saying what happened
5241 for this particular host, except in the case of authentication and TLS
5242 failures, where the log has already been written. If all hosts defer a
5243 general message is written at the end. */
5245 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5246 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5247 write_logs(host, first_addr->message, first_addr->basic_errno);
5249 #ifndef DISABLE_EVENT
5251 deferred_event_raise(first_addr, host, US"msg:host:defer");
5254 /* If STARTTLS was accepted, but there was a failure in setting up the
5255 TLS session (usually a certificate screwup), and the host is not in
5256 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5257 TLS forcibly turned off. We have to start from scratch with a new SMTP
5258 connection. That's why the retry is done from here, not from within
5259 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5260 session, so the in-clear transmission after those errors, if permitted,
5261 happens inside smtp_deliver().] */
5265 && first_addr->basic_errno == ERRNO_TLSFAILURE
5266 && ob->tls_tempfail_tryclear
5267 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5270 log_write(0, LOG_MAIN,
5271 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5272 first_addr->message, host->name, host->address);
5273 first_addr = prepare_addresses(addrlist, host);
5274 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5275 &message_defer, TRUE);
5276 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5277 write_logs(host, first_addr->message, first_addr->basic_errno);
5278 # ifndef DISABLE_EVENT
5280 deferred_event_raise(first_addr, host, US"msg:host:defer");
5283 #endif /*DISABLE_TLS*/
5285 #ifndef DISABLE_EVENT
5286 /* If the last host gave a defer raise a per-message event */
5289 && unexpired_hosts_tried < ob->hosts_max_try
5290 && total_hosts_tried < ob->hosts_max_try_hardlimit
5292 && (message_defer || rc == DEFER)
5294 deferred_event_raise(first_addr, host, US"msg:defer");
5298 /* Delivery attempt finished */
5300 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5301 message_id, host->name, host->address, pistring, addrlist->address,
5302 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5304 /* Release serialization if set up */
5306 if (serialize_key) enq_end(serialize_key);
5308 /* If the result is DEFER, or if a host retry record is known to exist, we
5309 need to add an item to the retry chain for updating the retry database
5310 at the end of delivery. We only need to add the item to the top address,
5311 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5312 for any other delivery attempts using the same address. (It is copied into
5313 the unusable tree at the outer level, so even if different address blocks
5314 contain the same address, it still won't get tried again.) */
5316 if (rc == DEFER || retry_host_key)
5318 int delete_flag = rc != DEFER ? rf_delete : 0;
5319 if (!retry_host_key)
5322 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5323 US"retry_include_ip_address", ob->retry_include_ip_address,
5324 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5325 incl_ip = TRUE; /* error; use most-specific retry record */
5327 retry_host_key = incl_ip
5328 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5329 : string_sprintf("T:%S%s", host->name, pistring);
5332 /* If a delivery of another message over an existing SMTP connection
5333 yields DEFER, we do NOT set up retry data for the host. This covers the
5334 case when there are delays in routing the addresses in the second message
5335 that are so long that the server times out. This is alleviated by not
5336 routing addresses that previously had routing defers when handling an
5337 existing connection, but even so, this case may occur (e.g. if a
5338 previously happily routed address starts giving routing defers). If the
5339 host is genuinely down, another non-continued message delivery will
5340 notice it soon enough. */
5342 if (delete_flag != 0 || !continue_hostname)
5343 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5345 /* We may have tried an expired host, if its retry time has come; ensure
5346 the status reflects the expiry for the benefit of any other addresses. */
5350 host->status = host_is_expired
5351 ? hstatus_unusable_expired : hstatus_unusable;
5352 host->why = hwhy_deferred;
5356 /* If message_defer is set (host was OK, but every recipient got deferred
5357 because of some message-specific problem), or if that had happened
5358 previously so that a message retry key exists, add an appropriate item
5359 to the retry chain. Note that if there was a message defer but now there is
5360 a host defer, the message defer record gets deleted. That seems perfectly
5361 reasonable. Also, stop the message from being remembered as waiting
5362 for specific hosts. */
5364 if (message_defer || retry_message_key)
5366 int delete_flag = message_defer ? 0 : rf_delete;
5367 if (!retry_message_key)
5370 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5371 US"retry_include_ip_address", ob->retry_include_ip_address,
5372 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5373 incl_ip = TRUE; /* error; use most-specific retry record */
5375 retry_message_key = incl_ip
5376 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5378 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5380 retry_add_item(addrlist, retry_message_key,
5381 rf_message | rf_host | delete_flag);
5382 update_waiting = FALSE;
5385 /* Any return other than DEFER (that is, OK or ERROR) means that the
5386 addresses have got their final statuses filled in for this host. In the OK
5387 case, see if any of them are deferred. */
5390 for (address_item * addr = addrlist; addr; addr = addr->next)
5391 if (addr->transport_return == DEFER)
5393 some_deferred = TRUE;
5397 /* If no addresses deferred or the result was ERROR, return. We do this for
5398 ERROR because a failing filter set-up or add_headers expansion is likely to
5399 fail for any host we try. */
5401 if (rc == ERROR || (rc == OK && !some_deferred))
5403 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5404 return TRUE; /* Each address has its status */
5407 /* If the result was DEFER or some individual addresses deferred, let
5408 the loop run to try other hosts with the deferred addresses, except for the
5409 case when we were trying to deliver down an existing channel and failed.
5410 Don't try any other hosts in this case. */
5412 if (continue_hostname) break;
5414 /* If the whole delivery, or some individual addresses, were deferred and
5415 there are more hosts that could be tried, do not count this host towards
5416 the hosts_max_try limit if the age of the message is greater than the
5417 maximum retry time for this host. This means we may try try all hosts,
5418 ignoring the limit, when messages have been around for some time. This is
5419 important because if we don't try all hosts, the address will never time
5420 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5422 if ((rc == DEFER || some_deferred) && nexthost)
5425 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5427 if (retry && retry->rules)
5429 retry_rule *last_rule;
5430 for (last_rule = retry->rules;
5432 last_rule = last_rule->next);
5433 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5435 else timedout = TRUE; /* No rule => timed out */
5439 unexpired_hosts_tried--;
5440 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5441 "hosts_max_try (message older than host's retry time)\n");
5447 if (unexpired_hosts_tried >= ob->hosts_max_try)
5448 debug_printf("reached transport hosts_max_try limit %d\n",
5450 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5451 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5452 ob->hosts_max_try_hardlimit);
5455 testharness_pause_ms(500); /* let server debug out */
5456 } /* End of loop for trying multiple hosts. */
5458 /* If we failed to find a matching host in the list, for an already-open
5459 connection, just close it and start over with the list. This can happen
5460 for routing that changes from run to run, or big multi-IP sites with
5463 if (continue_hostname && !continue_host_tried)
5465 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5467 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5469 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5471 /*XXX doublecheck that! */
5473 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
5475 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
5476 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
5477 cutthrough.cctx.tls_ctx = NULL;
5478 cutthrough.is_tls = FALSE;
5482 (void) write(fd, US"QUIT\r\n", 6);
5485 cutthrough.cctx.sock = -1;
5486 continue_hostname = NULL;
5487 goto retry_non_continued;
5490 /* This is the end of the loop that repeats iff expired is TRUE and
5491 ob->delay_after_cutoff is FALSE. The second time round we will
5492 try those hosts that haven't been tried since the message arrived. */
5496 debug_printf("all IP addresses skipped or deferred at least one address\n");
5497 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
5498 debug_printf("retrying IP addresses not tried since message arrived\n");
5503 /* Get here if all IP addresses are skipped or defer at least one address. In
5504 MUA wrapper mode, this will happen only for connection or other non-message-
5505 specific failures. Force the delivery status for all addresses to FAIL. */
5509 for (address_item * addr = addrlist; addr; addr = addr->next)
5510 addr->transport_return = FAIL;
5514 /* In the normal, non-wrapper case, add a standard message to each deferred
5515 address if there hasn't been an error, that is, if it hasn't actually been
5516 tried this time. The variable "expired" will be FALSE if any deliveries were
5517 actually tried, or if there was at least one host that was not expired. That
5518 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
5519 a delivery has been tried, an error code will be set, and the failing of the
5520 message is handled by the retry code later.
5522 If queue_smtp is set, or this transport was called to send a subsequent message
5523 down an existing TCP/IP connection, and something caused the host not to be
5524 found, we end up here, but can detect these cases and handle them specially. */
5526 for (address_item * addr = addrlist; addr; addr = addr->next)
5528 /* If host is not NULL, it means that we stopped processing the host list
5529 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
5530 means we need to behave as if some hosts were skipped because their retry
5531 time had not come. Specifically, this prevents the address from timing out.
5532 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
5533 hosts were tried. */
5536 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5539 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
5540 "hosts were tried\n");
5545 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
5546 setflag(addr, af_retry_skipped);
5549 if (f.queue_smtp) /* no deliveries attempted */
5551 addr->transport_return = DEFER;
5552 addr->basic_errno = 0;
5553 addr->message = US"SMTP delivery explicitly queued";
5556 else if ( addr->transport_return == DEFER
5557 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
5561 addr->basic_errno = ERRNO_HRETRY;
5562 if (continue_hostname)
5563 addr->message = US"no host found for existing SMTP connection";
5566 setflag(addr, af_pass_message); /* This is not a security risk */
5567 addr->message = string_sprintf(
5568 "all hosts%s have been failing for a long time %s",
5569 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
5570 ob->delay_after_cutoff
5571 ? US"(and retry time not reached)"
5572 : US"and were last tried after this message arrived");
5574 /* If we are already using fallback hosts, or there are no fallback hosts
5575 defined, convert the result to FAIL to cause a bounce. */
5577 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
5578 addr->transport_return = FAIL;
5583 if (hosts_retry == hosts_total)
5584 s = "retry time not reached for any host%s";
5585 else if (hosts_fail == hosts_total)
5586 s = "all host address lookups%s failed permanently";
5587 else if (hosts_defer == hosts_total)
5588 s = "all host address lookups%s failed temporarily";
5589 else if (hosts_serial == hosts_total)
5590 s = "connection limit reached for all hosts%s";
5591 else if (hosts_fail+hosts_defer == hosts_total)
5592 s = "all host address lookups%s failed";
5594 s = "some host address lookups failed and retry time "
5595 "not reached for other hosts or connection limit reached%s";
5597 addr->message = string_sprintf(s,
5598 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
5603 /* Update the database which keeps information about which messages are waiting
5604 for which hosts to become available. For some message-specific errors, the
5605 update_waiting flag is turned off because we don't want follow-on deliveries in
5606 those cases. If this transport instance is explicitly limited to one message
5607 per connection then follow-on deliveries are not possible and there's no need
5608 to create/update the per-transport wait-<transport_name> database. */
5610 if (update_waiting && tblock->connection_max_messages != 1)
5611 transport_update_waiting(hostlist, tblock->name);
5615 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5617 return TRUE; /* Each address has its status */
5620 #endif /*!MACRO_PREDEF*/
5623 /* End of transport/smtp.c */