1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) The Exim Maintainers 2020 - 2023 */
6 /* Copyright (c) University of Cambridge 1995 - 2018 */
7 /* See the file NOTICE for conditions of use and distribution. */
8 /* SPDX-License-Identifier: GPL-2.0-or-later */
13 #if defined(SUPPORT_DANE) && defined(DISABLE_TLS)
14 # error TLS is required for DANE
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 #define LOFF(field) OPT_OFF(smtp_transport_options_block, field)
25 optionlist smtp_transport_options[] = {
26 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
27 OPT_OFF(transport_instance, expand_multi_domain) },
28 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
29 LOFF(expand_retry_include_ip_address) },
31 { "address_retry_include_sender", opt_bool,
32 LOFF(address_retry_include_sender) },
33 { "allow_localhost", opt_bool, LOFF(allow_localhost) },
34 #ifdef EXPERIMENTAL_ARC
35 { "arc_sign", opt_stringptr, LOFF(arc_sign) },
37 { "authenticated_sender", opt_stringptr, LOFF(authenticated_sender) },
38 { "authenticated_sender_force", opt_bool, LOFF(authenticated_sender_force) },
39 { "command_timeout", opt_time, LOFF(command_timeout) },
40 { "connect_timeout", opt_time, LOFF(connect_timeout) },
41 { "connection_max_messages", opt_int | opt_public,
42 OPT_OFF(transport_instance, connection_max_messages) },
44 { "dane_require_tls_ciphers", opt_stringptr, LOFF(dane_require_tls_ciphers) },
46 { "data_timeout", opt_time, LOFF(data_timeout) },
47 { "delay_after_cutoff", opt_bool, LOFF(delay_after_cutoff) },
49 { "dkim_canon", opt_stringptr, LOFF(dkim.dkim_canon) },
50 { "dkim_domain", opt_stringptr, LOFF(dkim.dkim_domain) },
51 { "dkim_hash", opt_stringptr, LOFF(dkim.dkim_hash) },
52 { "dkim_identity", opt_stringptr, LOFF(dkim.dkim_identity) },
53 { "dkim_private_key", opt_stringptr, LOFF(dkim.dkim_private_key) },
54 { "dkim_selector", opt_stringptr, LOFF(dkim.dkim_selector) },
55 { "dkim_sign_headers", opt_stringptr, LOFF(dkim.dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr, LOFF(dkim.dkim_strict) },
57 { "dkim_timestamps", opt_stringptr, LOFF(dkim.dkim_timestamps) },
59 { "dns_qualify_single", opt_bool, LOFF(dns_qualify_single) },
60 { "dns_search_parents", opt_bool, LOFF(dns_search_parents) },
61 { "dnssec_request_domains", opt_stringptr, LOFF(dnssec.request) },
62 { "dnssec_require_domains", opt_stringptr, LOFF(dnssec.require) },
63 { "dscp", opt_stringptr, LOFF(dscp) },
64 { "fallback_hosts", opt_stringptr, LOFF(fallback_hosts) },
65 { "final_timeout", opt_time, LOFF(final_timeout) },
66 { "gethostbyname", opt_bool, LOFF(gethostbyname) },
67 { "helo_data", opt_stringptr, LOFF(helo_data) },
68 #if !defined(DISABLE_TLS) && !defined(DISABLE_TLS_RESUME)
69 { "host_name_extract", opt_stringptr, LOFF(host_name_extract) },
71 { "hosts", opt_stringptr, LOFF(hosts) },
72 { "hosts_avoid_esmtp", opt_stringptr, LOFF(hosts_avoid_esmtp) },
73 { "hosts_avoid_pipelining", opt_stringptr, LOFF(hosts_avoid_pipelining) },
75 { "hosts_avoid_tls", opt_stringptr, LOFF(hosts_avoid_tls) },
77 { "hosts_max_try", opt_int, LOFF(hosts_max_try) },
78 { "hosts_max_try_hardlimit", opt_int, LOFF(hosts_max_try_hardlimit) },
80 { "hosts_nopass_tls", opt_stringptr, LOFF(hosts_nopass_tls) },
81 { "hosts_noproxy_tls", opt_stringptr, LOFF(hosts_noproxy_tls) },
83 { "hosts_override", opt_bool, LOFF(hosts_override) },
84 #ifndef DISABLE_PIPE_CONNECT
85 { "hosts_pipe_connect", opt_stringptr, LOFF(hosts_pipe_connect) },
87 { "hosts_randomize", opt_bool, LOFF(hosts_randomize) },
88 #if !defined(DISABLE_TLS) && !defined(DISABLE_OCSP)
89 { "hosts_request_ocsp", opt_stringptr, LOFF(hosts_request_ocsp) },
91 { "hosts_require_alpn", opt_stringptr, LOFF(hosts_require_alpn) },
92 { "hosts_require_auth", opt_stringptr, LOFF(hosts_require_auth) },
95 { "hosts_require_dane", opt_stringptr, LOFF(hosts_require_dane) },
98 { "hosts_require_ocsp", opt_stringptr, LOFF(hosts_require_ocsp) },
100 { "hosts_require_tls", opt_stringptr, LOFF(hosts_require_tls) },
102 { "hosts_try_auth", opt_stringptr, LOFF(hosts_try_auth) },
103 { "hosts_try_chunking", opt_stringptr, LOFF(hosts_try_chunking) },
105 { "hosts_try_dane", opt_stringptr, LOFF(hosts_try_dane) },
107 { "hosts_try_fastopen", opt_stringptr, LOFF(hosts_try_fastopen) },
109 { "hosts_try_prdr", opt_stringptr, LOFF(hosts_try_prdr) },
112 { "hosts_verify_avoid_tls", opt_stringptr, LOFF(hosts_verify_avoid_tls) },
114 { "interface", opt_stringptr, LOFF(interface) },
115 { "keepalive", opt_bool, LOFF(keepalive) },
116 { "lmtp_ignore_quota", opt_bool, LOFF(lmtp_ignore_quota) },
117 { "max_rcpt", opt_stringptr | opt_public,
118 OPT_OFF(transport_instance, max_addresses) },
119 { "message_linelength_limit", opt_int, LOFF(message_linelength_limit) },
120 { "multi_domain", opt_expand_bool | opt_public,
121 OPT_OFF(transport_instance, multi_domain) },
122 { "port", opt_stringptr, LOFF(port) },
123 { "protocol", opt_stringptr, LOFF(protocol) },
124 { "retry_include_ip_address", opt_expand_bool, LOFF(retry_include_ip_address) },
125 { "serialize_hosts", opt_stringptr, LOFF(serialize_hosts) },
126 { "size_addition", opt_int, LOFF(size_addition) },
128 { "socks_proxy", opt_stringptr, LOFF(socks_proxy) },
131 { "tls_alpn", opt_stringptr, LOFF(tls_alpn) },
132 { "tls_certificate", opt_stringptr, LOFF(tls_certificate) },
133 { "tls_crl", opt_stringptr, LOFF(tls_crl) },
134 { "tls_dh_min_bits", opt_int, LOFF(tls_dh_min_bits) },
135 { "tls_privatekey", opt_stringptr, LOFF(tls_privatekey) },
136 { "tls_require_ciphers", opt_stringptr, LOFF(tls_require_ciphers) },
137 # ifndef DISABLE_TLS_RESUME
138 { "tls_resumption_hosts", opt_stringptr, LOFF(tls_resumption_hosts) },
140 { "tls_sni", opt_stringptr, LOFF(tls_sni) },
141 { "tls_tempfail_tryclear", opt_bool, LOFF(tls_tempfail_tryclear) },
142 { "tls_try_verify_hosts", opt_stringptr, LOFF(tls_try_verify_hosts) },
143 { "tls_verify_cert_hostnames", opt_stringptr, LOFF(tls_verify_cert_hostnames)},
144 { "tls_verify_certificates", opt_stringptr, LOFF(tls_verify_certificates) },
145 { "tls_verify_hosts", opt_stringptr, LOFF(tls_verify_hosts) },
148 { "utf8_downconvert", opt_stringptr, LOFF(utf8_downconvert) },
152 /* Size of the options list. An extern variable has to be used so that its
153 address can appear in the tables drtables.c. */
155 int smtp_transport_options_count = nelem(smtp_transport_options);
161 smtp_transport_options_block smtp_transport_option_defaults = {0};
162 void smtp_transport_init(transport_instance *tblock) {}
163 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
164 void smtp_transport_closedown(transport_instance *tblock) {}
166 #else /*!MACRO_PREDEF*/
169 /* Default private options block for the smtp transport. */
171 smtp_transport_options_block smtp_transport_option_defaults = {
172 /* All non-mentioned elements 0/NULL/FALSE */
173 .helo_data = US"$primary_hostname",
174 .protocol = US"smtp",
175 .hosts_try_chunking = US"*",
177 .hosts_try_dane = US"*",
179 .hosts_try_fastopen = US"*",
181 .hosts_try_prdr = US"*",
184 .hosts_request_ocsp = US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
186 .command_timeout = 5*60,
187 .connect_timeout = 5*60,
188 .data_timeout = 5*60,
189 .final_timeout = 10*60,
190 .size_addition = 1024,
192 .hosts_max_try_hardlimit = 50,
193 .message_linelength_limit = 998,
194 .address_retry_include_sender = TRUE,
195 .dns_qualify_single = TRUE,
196 .dnssec = { .request= US"*", .require=NULL },
197 .delay_after_cutoff = TRUE,
199 .retry_include_ip_address = TRUE,
201 .tls_verify_certificates = US"system",
202 .tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
203 .tls_tempfail_tryclear = TRUE,
204 .tls_try_verify_hosts = US"*",
205 .tls_verify_cert_hostnames = US"*",
208 .utf8_downconvert = US"-1",
212 { .dkim_hash = US"sha256", },
216 /* some DSN flags for use later */
218 static int rf_list[] = {rf_notify_never, rf_notify_success,
219 rf_notify_failure, rf_notify_delay };
221 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
227 static uschar *smtp_command; /* Points to last cmd for error messages */
228 static uschar *mail_command; /* Points to MAIL cmd for error messages */
229 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
230 static BOOL update_waiting; /* TRUE to update the "wait" database */
232 /*XXX move to smtp_context */
233 static BOOL pipelining_active; /* current transaction is in pipe mode */
236 static unsigned ehlo_response(uschar * buf, unsigned checks);
238 /* sync_responses() return codes */
240 #define RESP_BIT_HAD_5XX BIT(1)
241 #define RESP_BIT_HAD_2XX BIT(0)
242 #define RESP_HAD_2_AND_5 (RESP_BIT_HAD_2XX | RESP_BIT_HAD_5XX)
243 #define RESP_NOERROR 0
244 #define RESP_RCPT_TIMEO -1
245 #define RESP_RCPT_ERROR -2
246 #define RESP_MAIL_OR_DATA_ERROR -3
247 #define RESP_EPIPE_EHLO_ERR -4
248 #define RESP_EHLO_ERR_TLS -5
250 /******************************************************************************/
253 smtp_deliver_init(void)
257 const pcre2_code ** re;
258 const uschar * string;
261 { ®ex_AUTH, AUTHS_REGEX },
262 { ®ex_CHUNKING, US"\\n250[\\s\\-]CHUNKING(\\s|\\n|$)" },
263 { ®ex_DSN, US"\\n250[\\s\\-]DSN(\\s|\\n|$)" },
264 { ®ex_IGNOREQUOTA, US"\\n250[\\s\\-]IGNOREQUOTA(\\s|\\n|$)" },
265 { ®ex_PIPELINING, US"\\n250[\\s\\-]PIPELINING(\\s|\\n|$)" },
266 { ®ex_SIZE, US"\\n250[\\s\\-]SIZE(\\s|\\n|$)" },
269 { ®ex_STARTTLS, US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)" },
272 { ®ex_PRDR, US"\\n250[\\s\\-]PRDR(\\s|\\n|$)" },
275 { ®ex_UTF8, US"\\n250[\\s\\-]SMTPUTF8(\\s|\\n|$)" },
277 #ifndef DISABLE_PIPE_CONNECT
278 { ®ex_EARLY_PIPE, US"\\n250[\\s\\-]" EARLY_PIPE_FEATURE_NAME "(\\s|\\n|$)" },
280 #ifdef EXPERIMENTAL_ESMTP_LIMITS
281 { ®ex_LIMITS, US"\\n250[\\s\\-]LIMITS\\s" },
285 for (struct list * l = list; l < list + nelem(list); l++)
287 *l->re = regex_must_compile(l->string, MCS_NOFLAGS, TRUE);
291 /*************************************************
292 * Setup entry point *
293 *************************************************/
295 /* This function is called when the transport is about to be used,
296 but before running it in a sub-process. It is used for two things:
298 (1) To set the fallback host list in addresses, when delivering.
299 (2) To pass back the interface, port, protocol, and other options, for use
300 during callout verification.
303 tblock pointer to the transport instance block
304 addrlist list of addresses about to be transported
305 tf if not NULL, pointer to block in which to return options
306 uid the uid that will be set (not used)
307 gid the gid that will be set (not used)
308 errmsg place for error message (not used)
310 Returns: OK always (FAIL, DEFER not used)
314 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
315 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
317 smtp_transport_options_block *ob = SOB tblock->options_block;
319 /* Pass back options if required. This interface is getting very messy. */
323 tf->interface = ob->interface;
325 tf->protocol = ob->protocol;
326 tf->hosts = ob->hosts;
327 tf->hosts_override = ob->hosts_override;
328 tf->hosts_randomize = ob->hosts_randomize;
329 tf->gethostbyname = ob->gethostbyname;
330 tf->qualify_single = ob->dns_qualify_single;
331 tf->search_parents = ob->dns_search_parents;
332 tf->helo_data = ob->helo_data;
335 /* Set the fallback host list for all the addresses that don't have fallback
336 host lists, provided that the local host wasn't present in the original host
339 if (!testflag(addrlist, af_local_host_removed))
340 for (; addrlist; addrlist = addrlist->next)
341 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
348 /*************************************************
349 * Initialization entry point *
350 *************************************************/
352 /* Called for each instance, after its options have been read, to
353 enable consistency checks to be done, or anything else that needs
356 Argument: pointer to the transport instance block
361 smtp_transport_init(transport_instance *tblock)
363 smtp_transport_options_block * ob = SOB tblock->options_block;
364 int old_pool = store_pool;
366 /* Retry_use_local_part defaults FALSE if unset */
368 if (tblock->retry_use_local_part == TRUE_UNSET)
369 tblock->retry_use_local_part = FALSE;
371 /* Set the default port according to the protocol */
374 ob->port = strcmpic(ob->protocol, US"lmtp") == 0
376 : strcmpic(ob->protocol, US"smtps") == 0
377 ? US"smtps" : US"smtp";
379 /* Set up the setup entry point, to be called before subprocesses for this
382 tblock->setup = smtp_transport_setup;
384 /* Complain if any of the timeouts are zero. */
386 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
387 ob->final_timeout <= 0)
388 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
389 "command, data, or final timeout value is zero for %s transport",
392 /* If hosts_override is set and there are local hosts, set the global
393 flag that stops verify from showing router hosts. */
395 if (ob->hosts_override && ob->hosts) tblock->overrides_hosts = TRUE;
397 /* If there are any fallback hosts listed, build a chain of host items
398 for them, but do not do any lookups at this time. */
400 store_pool = POOL_PERM;
401 host_build_hostlist(&ob->fallback_hostlist, ob->fallback_hosts, FALSE);
402 store_pool = old_pool;
409 /*************************************************
410 * Set delivery info into all active addresses *
411 *************************************************/
413 /* Only addresses whose status is >= PENDING are relevant. A lesser
414 status means that an address is not currently being processed.
417 addrlist points to a chain of addresses
418 errno_value to put in each address's errno field
419 msg to put in each address's message field
420 rc to put in each address's transport_return field
421 pass_message if TRUE, set the "pass message" flag in the address
422 host if set, mark addrs as having used this host
423 smtp_greeting from peer
424 helo_response from peer
425 start points to timestamp of delivery start
427 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
428 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
429 this particular type of timeout.
435 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
436 BOOL pass_message, host_item * host,
437 #ifdef EXPERIMENTAL_DSN_INFO
438 const uschar * smtp_greeting, const uschar * helo_response,
440 struct timeval * start
444 struct timeval deliver_time;
446 if (errno_value == ERRNO_CONNECTTIMEOUT)
448 errno_value = ETIMEDOUT;
449 orvalue = RTEF_CTOUT;
451 timesince(&deliver_time, start);
453 for (address_item * addr = addrlist; addr; addr = addr->next)
454 if (addr->transport_return >= PENDING)
456 addr->basic_errno = errno_value;
457 addr->more_errno |= orvalue;
458 addr->delivery_time = deliver_time;
462 if (pass_message) setflag(addr, af_pass_message);
464 addr->transport_return = rc;
467 addr->host_used = host;
468 #ifdef EXPERIMENTAL_DSN_INFO
470 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
471 addr->smtp_greeting = smtp_greeting;
474 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
475 addr->helo_response = helo_response;
482 set_errno_nohost(address_item * addrlist, int errno_value, uschar * msg, int rc,
483 BOOL pass_message, struct timeval * start)
485 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL,
486 #ifdef EXPERIMENTAL_DSN_INFO
493 /*************************************************
494 * Check an SMTP response *
495 *************************************************/
497 /* This function is given an errno code and the SMTP response buffer
498 to analyse, together with the host identification for generating messages. It
499 sets an appropriate message and puts the first digit of the response code into
500 the yield variable. If no response was actually read, a suitable digit is
504 host the current host, to get its name for messages
505 errno_value pointer to the errno value
506 more_errno from the top address for use with ERRNO_FILTER_FAIL
507 buffer the SMTP response buffer
508 yield where to put a one-digit SMTP response code
509 message where to put an error message
510 pass_message set TRUE if message is an SMTP response
512 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
516 check_response(host_item *host, int *errno_value, int more_errno,
517 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
519 uschar * pl = pipelining_active ? US"pipelined " : US"";
522 *yield = '4'; /* Default setting is to give a temporary error */
526 case ETIMEDOUT: /* Handle response timeout */
527 *message = US string_sprintf("SMTP timeout after %s%s",
529 if (transport_count > 0)
530 *message = US string_sprintf("%s (%d bytes written)", *message,
534 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
535 s = string_printing(buffer);
536 while (isspace(*s)) s++;
538 ? string_sprintf("Malformed SMTP reply (an empty line) "
539 "in response to %s%s", pl, smtp_command)
540 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
541 pl, smtp_command, s);
544 case ERRNO_TLSFAILURE: /* Handle bad first read; can happen with
546 *message = US"bad first read from TLS conn";
549 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
550 can't send QUIT as we mustn't end the DATA. */
551 *message = string_sprintf("transport filter process failed (%d)%s",
553 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
556 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
557 can't send QUIT as we mustn't end the DATA. */
559 string_sprintf("failed to expand headers_add or headers_remove: %s",
560 expand_string_message);
563 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
564 *message = US"failed to write a data block";
568 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
569 *message = US"utf8 support required but not offered for forwarding";
570 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
575 /* Handle error responses from the remote mailer. */
579 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
580 "%s", pl, smtp_command, s = string_printing(buffer));
581 *pass_message = TRUE;
586 /* No data was read. If there is no errno, this must be the EOF (i.e.
587 connection closed) case, which causes deferral. An explicit connection reset
588 error has the same effect. Otherwise, put the host's identity in the message,
589 leaving the errno value to be interpreted as well. In all cases, we have to
590 assume the connection is now dead. */
592 if (*errno_value == 0 || *errno_value == ECONNRESET)
594 *errno_value = ERRNO_SMTPCLOSED;
595 *message = US string_sprintf("Remote host closed connection "
596 "in response to %s%s", pl, smtp_command);
599 *message = US string_sprintf("%s [%s]", host->name, host->address);
606 /*************************************************
607 * Write error message to logs *
608 *************************************************/
610 /* This writes to the main log and to the message log.
613 host the current host
614 detail the current message (addr_item->message)
615 basic_errno the errno (addr_item->basic_errno)
621 write_logs(const host_item *host, const uschar *suffix, int basic_errno)
623 gstring * message = LOGGING(outgoing_port)
624 ? string_fmt_append(NULL, "H=%s [%s]:%d", host->name, host->address,
625 host->port == PORT_NONE ? 25 : host->port)
626 : string_fmt_append(NULL, "H=%s [%s]", host->name, host->address);
630 message = string_fmt_append(message, ": %s", suffix);
632 message = string_fmt_append(message, ": %s", strerror(basic_errno));
635 message = string_fmt_append(message, " %s", exim_errstr(basic_errno));
637 log_write(0, LOG_MAIN, "%Y", message);
638 deliver_msglog("%s %.*s\n", tod_stamp(tod_log), message->ptr, message->s);
642 msglog_line(host_item * host, uschar * message)
644 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
645 host->name, host->address, message);
650 #ifndef DISABLE_EVENT
651 /*************************************************
652 * Post-defer action *
653 *************************************************/
655 /* This expands an arbitrary per-transport string.
656 It might, for example, be used to write to the database log.
659 addr the address item containing error information
660 host the current host
667 deferred_event_raise(address_item * addr, host_item * host, uschar * evstr)
669 uschar * action = addr->transport->event_action;
670 const uschar * save_domain, * save_local;
675 save_domain = deliver_domain;
676 save_local = deliver_localpart;
678 /*XXX would ip & port already be set up? */
679 deliver_host_address = string_copy(host->address);
680 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
681 event_defer_errno = addr->basic_errno;
683 router_name = addr->router->name;
684 transport_name = addr->transport->name;
685 deliver_domain = addr->domain;
686 deliver_localpart = addr->local_part;
688 (void) event_raise(action, evstr,
690 ? addr->basic_errno > 0
691 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
692 : string_copy(addr->message)
693 : addr->basic_errno > 0
694 ? string_copy(US strerror(addr->basic_errno))
698 deliver_localpart = save_local;
699 deliver_domain = save_domain;
700 router_name = transport_name = NULL;
704 /*************************************************
705 * Reap SMTP specific responses *
706 *************************************************/
708 smtp_discard_responses(smtp_context * sx, smtp_transport_options_block * ob,
711 uschar flushbuffer[4096];
715 if (!smtp_read_response(sx, flushbuffer, sizeof(flushbuffer),
716 '2', ob->command_timeout)
717 && (errno != 0 || flushbuffer[0] == 0))
724 /* Return boolean success */
727 smtp_reap_banner(smtp_context * sx)
730 #if defined(__linux__) && defined(TCP_QUICKACK)
731 { /* Hack to get QUICKACK disabled; has to be right after 3whs, and has to on->off */
732 int sock = sx->cctx.sock;
733 struct pollfd p = {.fd = sock, .events = POLLOUT};
734 if (poll(&p, 1, 1000) >= 0) /* retval test solely for compiler quitening */
736 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &on, sizeof(on));
737 (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
741 good_response = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
742 '2', (SOB sx->conn_args.ob)->command_timeout);
743 #ifdef EXPERIMENTAL_DSN_INFO
744 sx->smtp_greeting = string_copy(sx->buffer);
746 return good_response;
750 smtp_reap_ehlo(smtp_context * sx)
752 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
753 (SOB sx->conn_args.ob)->command_timeout))
755 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
757 #ifdef EXPERIMENTAL_DSN_INFO
758 sx->helo_response = string_copy(sx->buffer);
764 #ifdef EXPERIMENTAL_DSN_INFO
765 sx->helo_response = string_copy(sx->buffer);
767 #ifndef DISABLE_EVENT
768 (void) event_raise(sx->conn_args.tblock->event_action,
769 US"smtp:ehlo", sx->buffer, NULL);
775 #if !defined(DISABLE_TLS) && !defined(DISABLE_TLS_RESUME)
777 /* Grab a string differentiating server behind a loadbalancer, for TLS
778 resumption when such servers do not share a session-cache */
781 ehlo_response_lbserver(smtp_context * sx, const uschar * name_extract)
784 uschar * save_item = iterate_item;
786 if (sx->conn_args.have_lbserver)
788 iterate_item = sx->buffer;
789 s = expand_cstring(name_extract);
790 iterate_item = save_item;
791 sx->conn_args.host_lbserver = s && !*s ? NULL : s;
792 sx->conn_args.have_lbserver = TRUE;
798 /******************************************************************************/
800 #ifdef EXPERIMENTAL_ESMTP_LIMITS
801 /* If TLS, or TLS not offered, called with the EHLO response in the buffer.
802 Check it for a LIMITS keyword and parse values into the smtp context structure.
804 We don't bother with peers that we won't talk TLS to, even though they can,
805 just ignore their LIMITS advice (if any) and treat them as if they do not.
806 This saves us dealing with a duplicate set of values. */
809 ehlo_response_limits_read(smtp_context * sx)
813 /* matches up to just after the first space after the keyword */
815 if (regex_match(regex_LIMITS, sx->buffer, -1, &match))
816 for (const uschar * s = sx->buffer + Ustrlen(match); *s; )
818 while (isspace(*s)) s++;
819 if (*s == '\n') break;
821 if (strncmpic(s, US"MAILMAX=", 8) == 0)
823 sx->peer_limit_mail = atoi(CS (s += 8));
824 while (isdigit(*s)) s++;
826 else if (strncmpic(s, US"RCPTMAX=", 8) == 0)
828 sx->peer_limit_rcpt = atoi(CS (s += 8));
829 while (isdigit(*s)) s++;
831 else if (strncmpic(s, US"RCPTDOMAINMAX=", 14) == 0)
833 sx->peer_limit_rcptdom = atoi(CS (s += 14));
834 while (isdigit(*s)) s++;
837 while (*s && !isspace(*s)) s++;
841 /* Apply given values to the current connection */
843 ehlo_limits_apply(smtp_context * sx,
844 unsigned limit_mail, unsigned limit_rcpt, unsigned limit_rcptdom)
846 if (limit_mail && limit_mail < sx->max_mail) sx->max_mail = limit_mail;
847 if (limit_rcpt && limit_rcpt < sx->max_rcpt) sx->max_rcpt = limit_rcpt;
850 DEBUG(D_transport) debug_printf("will treat as !multi_domain\n");
851 sx->single_rcpt_domain = TRUE;
855 /* Apply values from EHLO-resp to the current connection */
857 ehlo_response_limits_apply(smtp_context * sx)
859 ehlo_limits_apply(sx, sx->peer_limit_mail, sx->peer_limit_rcpt,
860 sx->peer_limit_rcptdom);
863 /* Apply values read from cache to the current connection */
865 ehlo_cache_limits_apply(smtp_context * sx)
867 # ifndef DISABLE_PIPE_CONNECT
868 ehlo_limits_apply(sx, sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
869 sx->ehlo_resp.limit_rcptdom);
872 #endif /*EXPERIMENTAL_ESMTP_LIMITS*/
874 /******************************************************************************/
876 #ifndef DISABLE_PIPE_CONNECT
878 ehlo_cache_key(const smtp_context * sx)
880 host_item * host = sx->conn_args.host;
881 return Ustrchr(host->address, ':')
882 ? string_sprintf("[%s]:%d.EHLO", host->address,
883 host->port == PORT_NONE ? sx->port : host->port)
884 : string_sprintf("%s:%d.EHLO", host->address,
885 host->port == PORT_NONE ? sx->port : host->port);
888 /* Cache EHLO-response info for use by early-pipe.
890 - During a normal flow on EHLO response (either cleartext or under TLS),
891 when we are willing to do PIPECONNECT and it is offered
892 - During an early-pipe flow on receiving the actual EHLO response and noting
893 disparity versus the cached info used, when PIPECONNECT is still being offered
895 We assume that suitable values have been set in the sx.ehlo_resp structure for
896 features and auths; we handle the copy of limits. */
899 write_ehlo_cache_entry(smtp_context * sx)
901 open_db dbblock, * dbm_file;
903 # ifdef EXPERIMENTAL_ESMTP_LIMITS
904 sx->ehlo_resp.limit_mail = sx->peer_limit_mail;
905 sx->ehlo_resp.limit_rcpt = sx->peer_limit_rcpt;
906 sx->ehlo_resp.limit_rcptdom = sx->peer_limit_rcptdom;
909 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
911 uschar * ehlo_resp_key = ehlo_cache_key(sx);
912 dbdata_ehlo_resp er = { .data = sx->ehlo_resp };
915 # ifdef EXPERIMENTAL_ESMTP_LIMITS
916 if (sx->ehlo_resp.limit_mail || sx->ehlo_resp.limit_rcpt || sx->ehlo_resp.limit_rcptdom)
917 debug_printf("writing clr %04x/%04x cry %04x/%04x lim %05d/%05d/%05d\n",
918 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
919 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths,
920 sx->ehlo_resp.limit_mail, sx->ehlo_resp.limit_rcpt,
921 sx->ehlo_resp.limit_rcptdom);
924 debug_printf("writing clr %04x/%04x cry %04x/%04x\n",
925 sx->ehlo_resp.cleartext_features, sx->ehlo_resp.cleartext_auths,
926 sx->ehlo_resp.crypted_features, sx->ehlo_resp.crypted_auths);
928 dbfn_write(dbm_file, ehlo_resp_key, &er, (int)sizeof(er));
929 dbfn_close(dbm_file);
934 invalidate_ehlo_cache_entry(smtp_context * sx)
936 open_db dbblock, * dbm_file;
938 if ( sx->early_pipe_active
939 && (dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
941 uschar * ehlo_resp_key = ehlo_cache_key(sx);
944 dbdata_ehlo_resp * er;
946 if (!(er = dbfn_read_enforce_length(dbm_file, ehlo_resp_key, sizeof(dbdata_ehlo_resp))))
947 debug_printf("no ehlo-resp record!\n");
949 debug_printf("ehlo-resp record is %d seconds old\n", time(NULL) - er->time_stamp);
952 dbfn_delete(dbm_file, ehlo_resp_key);
953 dbfn_close(dbm_file);
958 read_ehlo_cache_entry(smtp_context * sx)
963 if (!(dbm_file = dbfn_open(US"misc", O_RDONLY, &dbblock, FALSE, TRUE)))
964 { DEBUG(D_transport) debug_printf("ehlo-cache: no misc DB\n"); }
967 uschar * ehlo_resp_key = ehlo_cache_key(sx);
968 dbdata_ehlo_resp * er;
970 if (!(er = dbfn_read_enforce_length(dbm_file, ehlo_resp_key, sizeof(dbdata_ehlo_resp))))
971 { DEBUG(D_transport) debug_printf("no ehlo-resp record\n"); }
972 else if (time(NULL) - er->time_stamp > retry_data_expire)
974 DEBUG(D_transport) debug_printf("ehlo-resp record too old\n");
975 dbfn_close(dbm_file);
976 if ((dbm_file = dbfn_open(US"misc", O_RDWR, &dbblock, TRUE, TRUE)))
977 dbfn_delete(dbm_file, ehlo_resp_key);
982 # ifdef EXPERIMENTAL_ESMTP_LIMITS
983 if (er->data.limit_mail || er->data.limit_rcpt || er->data.limit_rcptdom)
984 debug_printf("EHLO response bits from cache:"
985 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x lim %05d/%05d/%05d\n",
986 er->data.cleartext_features, er->data.cleartext_auths,
987 er->data.crypted_features, er->data.crypted_auths,
988 er->data.limit_mail, er->data.limit_rcpt, er->data.limit_rcptdom);
991 debug_printf("EHLO response bits from cache:"
992 " cleartext 0x%04x/0x%04x crypted 0x%04x/0x%04x\n",
993 er->data.cleartext_features, er->data.cleartext_auths,
994 er->data.crypted_features, er->data.crypted_auths);
996 sx->ehlo_resp = er->data;
997 # ifdef EXPERIMENTAL_ESMTP_LIMITS
998 ehlo_cache_limits_apply(sx);
1000 dbfn_close(dbm_file);
1003 dbfn_close(dbm_file);
1010 /* Return an auths bitmap for the set of AUTH methods offered by the server
1011 which match our client-side authenticators. */
1013 static unsigned short
1014 study_ehlo_auths(smtp_context * sx)
1019 unsigned short authbits = 0;
1021 if (!sx->esmtp) return 0;
1022 if (!regex_AUTH) regex_AUTH = regex_must_compile(AUTHS_REGEX, MCS_NOFLAGS, TRUE);
1023 if (!regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)) return 0;
1024 expand_nmax = -1; /* reset */
1025 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1027 for (au = auths, authnum = 0; au; au = au->next, authnum++) if (au->client)
1029 const uschar * list = names;
1031 for (int sep = ' '; s = string_nextinlist(&list, &sep, NULL, 0); )
1032 if (strcmpic(au->public_name, s) == 0)
1033 { authbits |= BIT(authnum); break; }
1037 debug_printf("server offers %s AUTH, methods '%s', usable-bitmap 0x%04x\n",
1038 tls_out.active.sock >= 0 ? "crypted" : "plaintext", names, authbits);
1040 if (tls_out.active.sock >= 0)
1041 sx->ehlo_resp.crypted_auths = authbits;
1043 sx->ehlo_resp.cleartext_auths = authbits;
1050 /* Wait for and check responses for early-pipelining.
1052 Called from the lower-level smtp_read_response() function
1053 used for general code that assume synchronisation, if context
1054 flags indicate outstanding early-pipelining commands. Also
1055 called fom sync_responses() which handles pipelined commands.
1058 sx smtp connection context
1059 countp number of outstanding responses, adjusted on return
1063 DEFER error on first read of TLS'd conn
1064 FAIL SMTP error in response
1067 smtp_reap_early_pipe(smtp_context * sx, int * countp)
1069 BOOL pending_BANNER = sx->pending_BANNER;
1070 BOOL pending_EHLO = sx->pending_EHLO;
1073 sx->pending_BANNER = FALSE; /* clear early to avoid recursion */
1074 sx->pending_EHLO = FALSE;
1080 DEBUG(D_transport) debug_printf("%s expect banner\n", __FUNCTION__);
1082 if (!smtp_reap_banner(sx))
1084 DEBUG(D_transport) debug_printf("bad banner\n");
1085 if (tls_out.active.sock >= 0) rc = DEFER;
1088 /*XXX EXPERIMENTAL_ESMTP_LIMITS ? */
1090 # ifndef DISABLE_TLS_RESUME
1091 s = ((smtp_transport_options_block *)sx->conn_args.ob)->host_name_extract;
1092 if (!s) s = HNE_DEFAULT;
1093 ehlo_response_lbserver(sx, s);
1099 unsigned peer_offered;
1100 unsigned short authbits = 0, * ap;
1102 DEBUG(D_transport) debug_printf("%s expect ehlo\n", __FUNCTION__);
1104 if (!smtp_reap_ehlo(sx))
1106 DEBUG(D_transport) debug_printf("bad response for EHLO\n");
1107 if (tls_out.active.sock >= 0) rc = DEFER;
1111 /* Compare the actual EHLO response extensions and AUTH methods to the cached
1112 value we assumed; on difference, dump or rewrite the cache and arrange for a
1115 ap = tls_out.active.sock < 0
1116 ? &sx->ehlo_resp.cleartext_auths : &sx->ehlo_resp.crypted_auths;
1118 peer_offered = ehlo_response(sx->buffer,
1119 (tls_out.active.sock < 0 ? OPTION_TLS : 0)
1120 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
1121 | OPTION_UTF8 | OPTION_EARLY_PIPE
1123 # ifdef EXPERIMENTAL_ESMTP_LIMITS
1124 if (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1125 ehlo_response_limits_read(sx);
1127 if ( peer_offered != sx->peer_offered
1128 || (authbits = study_ehlo_auths(sx)) != *ap)
1131 debug_printf("EHLO %s extensions changed, 0x%04x/0x%04x -> 0x%04x/0x%04x\n",
1132 tls_out.active.sock < 0 ? "cleartext" : "crypted",
1133 sx->peer_offered, *ap, peer_offered, authbits);
1134 if (peer_offered & OPTION_EARLY_PIPE)
1136 *(tls_out.active.sock < 0
1137 ? &sx->ehlo_resp.cleartext_features : &sx->ehlo_resp.crypted_features) =
1140 write_ehlo_cache_entry(sx);
1144 invalidate_ehlo_cache_entry(sx);
1145 sx->early_pipe_active = FALSE; /* cancel further early-pipe on this conn */
1148 return OK; /* just carry on */
1150 # ifdef EXPERIMENTAL_ESMTP_LIMITS
1151 /* If we are handling LIMITS, compare the actual EHLO LIMITS values with the
1152 cached values and invalidate cache if different. OK to carry on with
1153 connect since values are advisory. */
1155 if ( (tls_out.active.sock >= 0 || !(peer_offered & OPTION_TLS))
1156 && ( sx->peer_limit_mail != sx->ehlo_resp.limit_mail
1157 || sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt
1158 || sx->peer_limit_rcptdom != sx->ehlo_resp.limit_rcptdom
1163 debug_printf("EHLO LIMITS changed:");
1164 if (sx->peer_limit_mail != sx->ehlo_resp.limit_mail)
1165 debug_printf(" MAILMAX %u -> %u\n", sx->ehlo_resp.limit_mail, sx->peer_limit_mail);
1166 else if (sx->peer_limit_rcpt != sx->ehlo_resp.limit_rcpt)
1167 debug_printf(" RCPTMAX %u -> %u\n", sx->ehlo_resp.limit_rcpt, sx->peer_limit_rcpt);
1169 debug_printf(" RCPTDOMAINMAX %u -> %u\n", sx->ehlo_resp.limit_rcptdom, sx->peer_limit_rcptdom);
1171 invalidate_ehlo_cache_entry(sx);
1179 invalidate_ehlo_cache_entry(sx);
1180 (void) smtp_discard_responses(sx, sx->conn_args.ob, *countp);
1183 #endif /*!DISABLE_PIPE_CONNECT*/
1186 /*************************************************
1187 * Synchronize SMTP responses *
1188 *************************************************/
1190 /* This function is called from smtp_deliver() to receive SMTP responses from
1191 the server, and match them up with the commands to which they relate. When
1192 PIPELINING is not in use, this function is called after every command, and is
1193 therefore somewhat over-engineered, but it is simpler to use a single scheme
1194 that works both with and without PIPELINING instead of having two separate sets
1197 The set of commands that are buffered up with pipelining may start with MAIL
1198 and may end with DATA; in between are RCPT commands that correspond to the
1199 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
1200 etc.) are never buffered.
1202 Errors after MAIL or DATA abort the whole process leaving the response in the
1203 buffer. After MAIL, pending responses are flushed, and the original command is
1204 re-instated in big_buffer for error messages. For RCPT commands, the remote is
1205 permitted to reject some recipient addresses while accepting others. However
1206 certain errors clearly abort the whole process. Set the value in
1207 transport_return to PENDING_OK if the address is accepted. If there is a
1208 subsequent general error, it will get reset accordingly. If not, it will get
1209 converted to OK at the end.
1212 sx smtp connection context
1213 count the number of responses to read
1214 pending_DATA 0 if last command sent was not DATA
1215 +1 if previously had a good recipient
1216 -1 if not previously had a good recipient
1218 Returns: 3 if at least one address had 2xx and one had 5xx
1219 2 if at least one address had 5xx but none had 2xx
1220 1 if at least one host had a 2xx response, but none had 5xx
1221 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
1222 -1 timeout while reading RCPT response
1223 -2 I/O or other non-response error for RCPT
1224 -3 DATA or MAIL failed - errno and buffer set
1225 -4 banner or EHLO failed (early-pipelining)
1226 -5 banner or EHLO failed (early-pipelining, TLS)
1230 sync_responses(smtp_context * sx, int count, int pending_DATA)
1232 address_item * addr = sx->sync_addr;
1233 smtp_transport_options_block * ob = sx->conn_args.ob;
1236 #ifndef DISABLE_PIPE_CONNECT
1238 if ((rc = smtp_reap_early_pipe(sx, &count)) != OK)
1239 return rc == FAIL ? RESP_EPIPE_EHLO_ERR : RESP_EHLO_ERR_TLS;
1242 /* Handle the response for a MAIL command. On error, reinstate the original
1243 command in big_buffer for error message use, and flush any further pending
1244 responses before returning, except after I/O errors and timeouts. */
1246 if (sx->pending_MAIL)
1248 DEBUG(D_transport) debug_printf("%s expect mail\n", __FUNCTION__);
1250 sx->pending_MAIL = sx->RCPT_452 = FALSE;
1251 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1252 '2', ob->command_timeout))
1254 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
1255 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
1256 if (errno == ERRNO_TLSFAILURE)
1257 return RESP_EHLO_ERR_TLS;
1258 if (errno == 0 && sx->buffer[0] != 0)
1261 if (sx->buffer[0] == '4')
1263 save_errno = ERRNO_MAIL4XX;
1264 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1266 count = smtp_discard_responses(sx, ob, count);
1270 if (pending_DATA) count--; /* Number of RCPT responses to come */
1271 while (count-- > 0) /* Mark any pending addrs with the host used */
1273 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
1274 addr->host_used = sx->conn_args.host;
1277 return RESP_MAIL_OR_DATA_ERROR;
1281 if (pending_DATA) count--; /* Number of RCPT responses to come */
1283 /* Read and handle the required number of RCPT responses, matching each one up
1284 with an address by scanning for the next address whose status is PENDING_DEFER.
1289 while (addr->transport_return != PENDING_DEFER)
1290 if (!(addr = addr->next))
1291 return RESP_RCPT_ERROR;
1293 /* The address was accepted */
1294 addr->host_used = sx->conn_args.host;
1296 DEBUG(D_transport) debug_printf("%s expect rcpt for %s\n", __FUNCTION__, addr->address);
1297 if (smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1298 '2', ob->command_timeout))
1300 yield |= RESP_BIT_HAD_2XX;
1301 addr->transport_return = PENDING_OK;
1303 /* If af_dr_retry_exists is set, there was a routing delay on this address;
1304 ensure that any address-specific retry record is expunged. We do this both
1305 for the basic key and for the version that also includes the sender. */
1307 if (testflag(addr, af_dr_retry_exists))
1309 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
1311 retry_add_item(addr, altkey, rf_delete);
1312 retry_add_item(addr, addr->address_retry_key, rf_delete);
1316 /* Error on first TLS read */
1318 else if (errno == ERRNO_TLSFAILURE)
1319 return RESP_EHLO_ERR_TLS;
1321 /* Timeout while reading the response */
1323 else if (errno == ETIMEDOUT)
1325 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
1326 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1327 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE, &sx->delivery_start);
1328 retry_add_item(addr, addr->address_retry_key, 0);
1329 update_waiting = FALSE;
1330 return RESP_RCPT_TIMEO;
1333 /* Handle other errors in obtaining an SMTP response by returning -1. This
1334 will cause all the addresses to be deferred. Restore the SMTP command in
1335 big_buffer for which we are checking the response, so the error message
1338 else if (errno != 0 || sx->buffer[0] == 0)
1340 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer }, * g = &gs;
1342 /* Use taint-unchecked routines for writing into big_buffer, trusting
1343 that we'll never expand it. */
1345 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, "RCPT TO:<%s>",
1346 transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes));
1347 string_from_gstring(g);
1348 return RESP_RCPT_ERROR;
1351 /* Handle SMTP permanent and temporary response codes. */
1356 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
1357 "%s", transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes),
1358 string_printing(sx->buffer));
1359 setflag(addr, af_pass_message);
1361 msglog_line(sx->conn_args.host, addr->message);
1363 /* The response was 5xx */
1365 if (sx->buffer[0] == '5')
1367 addr->transport_return = FAIL;
1368 yield |= RESP_BIT_HAD_5XX;
1371 /* The response was 4xx */
1375 addr->transport_return = DEFER;
1376 addr->basic_errno = ERRNO_RCPT4XX;
1377 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1381 #ifndef DISABLE_EVENT
1382 event_defer_errno = addr->more_errno;
1383 msg_event_raise(US"msg:rcpt:host:defer", addr);
1385 /* If a 452 and we've had at least one 2xx or 5xx, set next_addr to the
1386 start point for another MAIL command. */
1388 if (addr->more_errno >> 8 == 52 && yield > 0)
1390 if (!sx->RCPT_452) /* initialised at MAIL-ack above */
1393 debug_printf("%s: seen first 452 too-many-rcpts\n", __FUNCTION__);
1394 sx->RCPT_452 = TRUE;
1395 sx->next_addr = addr;
1397 addr->transport_return = PENDING_DEFER;
1398 addr->basic_errno = 0;
1402 /* Log temporary errors if there are more hosts to be tried.
1403 If not, log this last one in the == line. */
1405 if (sx->conn_args.host->next)
1406 if (LOGGING(outgoing_port))
1407 log_write(0, LOG_MAIN, "H=%s [%s]:%d %s", sx->conn_args.host->name,
1408 sx->conn_args.host->address,
1409 sx->port == PORT_NONE ? 25 : sx->port, addr->message);
1411 log_write(0, LOG_MAIN, "H=%s [%s]: %s", sx->conn_args.host->name,
1412 sx->conn_args.host->address, addr->message);
1414 #ifndef DISABLE_EVENT
1416 msg_event_raise(US"msg:rcpt:defer", addr);
1419 /* Do not put this message on the list of those waiting for specific
1420 hosts, as otherwise it is likely to be tried too often. */
1422 update_waiting = FALSE;
1424 /* Add a retry item for the address so that it doesn't get tried again
1425 too soon. If address_retry_include_sender is true, add the sender address
1426 to the retry key. */
1428 retry_add_item(addr,
1429 ob->address_retry_include_sender
1430 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
1431 : addr->address_retry_key,
1437 if (count && !(addr = addr->next))
1438 return RESP_RCPT_ERROR;
1439 } /* Loop for next RCPT response */
1441 /* Update where to start at for the next block of responses, unless we
1442 have already handled all the addresses. */
1444 if (addr) sx->sync_addr = addr->next;
1446 /* Handle a response to DATA. If we have not had any good recipients, either
1447 previously or in this block, the response is ignored. */
1449 if (pending_DATA != 0)
1451 DEBUG(D_transport) debug_printf("%s expect data\n", __FUNCTION__);
1452 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
1453 '3', ob->command_timeout))
1459 if (errno == ERRNO_TLSFAILURE) /* Error on first TLS read */
1460 return RESP_EHLO_ERR_TLS;
1462 if (pending_DATA > 0 || yield & RESP_BIT_HAD_2XX)
1464 if (errno == 0 && sx->buffer[0] == '4')
1466 errno = ERRNO_DATA4XX;
1467 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1469 return RESP_MAIL_OR_DATA_ERROR;
1471 (void)check_response(sx->conn_args.host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
1472 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
1473 "is in use and there were no good recipients\n", msg);
1477 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
1478 present) received 3xx. If any RCPTs were handled and yielded anything other
1479 than 4xx, yield will be set non-zero. */
1488 /* Try an authenticator's client entry */
1491 try_authenticator(smtp_context * sx, auth_instance * au)
1493 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1494 host_item * host = sx->conn_args.host; /* host to deliver to */
1497 /* Set up globals for error messages */
1499 authenticator_name = au->name;
1500 driver_srcfile = au->srcfile;
1501 driver_srcline = au->srcline;
1503 sx->outblock.authenticating = TRUE;
1504 rc = (au->info->clientcode)(au, sx, ob->command_timeout,
1505 sx->buffer, sizeof(sx->buffer));
1506 sx->outblock.authenticating = FALSE;
1507 driver_srcfile = authenticator_name = NULL; driver_srcline = 0;
1508 DEBUG(D_transport) debug_printf("%s authenticator yielded %s\n", au->name, rc_names[rc]);
1510 /* A temporary authentication failure must hold up delivery to
1511 this host. After a permanent authentication failure, we carry on
1512 to try other authentication methods. If all fail hard, try to
1513 deliver the message unauthenticated unless require_auth was set. */
1518 f.smtp_authenticated = TRUE; /* stops the outer loop */
1519 client_authenticator = au->name;
1520 if (au->set_client_id)
1521 client_authenticated_id = expand_string(au->set_client_id);
1524 /* Failure after writing a command */
1529 /* Failure after reading a response */
1533 uschar * logmsg = NULL;
1535 if (errno != 0 || sx->buffer[0] != '5') return FAIL;
1536 #ifndef DISABLE_EVENT
1538 uschar * save_name = sender_host_authenticated;
1539 sender_host_authenticated = au->name;
1540 if ((logmsg = event_raise(sx->conn_args.tblock->event_action, US"auth:fail",
1542 log_write(0, LOG_MAIN, "%s", logmsg);
1543 sender_host_authenticated = save_name;
1547 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1548 au->name, host->name, host->address, sx->buffer);
1552 /* Failure by some other means. In effect, the authenticator
1553 decided it wasn't prepared to handle this case. Typically this
1554 is the result of "fail" in an expansion string. Do we need to
1555 log anything here? Feb 2006: a message is now put in the buffer
1556 if logging is required. */
1559 if (*sx->buffer != 0)
1560 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1561 "authentication H=%s [%s] %s", au->name, host->name,
1562 host->address, sx->buffer);
1565 /* Internal problem, message in buffer. */
1568 set_errno_nohost(sx->addrlist, ERRNO_AUTHPROB, string_copy(sx->buffer),
1569 DEFER, FALSE, &sx->delivery_start);
1578 /* Do the client side of smtp-level authentication.
1581 sx smtp connection context
1583 sx->buffer should have the EHLO response from server (gets overwritten)
1586 OK Success, or failed (but not required): global "smtp_authenticated" set
1587 DEFER Failed authentication (and was required)
1588 ERROR Internal problem
1590 FAIL_SEND Failed communications - transmit
1595 smtp_auth(smtp_context * sx)
1597 host_item * host = sx->conn_args.host; /* host to deliver to */
1598 smtp_transport_options_block * ob = sx->conn_args.ob; /* transport options */
1599 int require_auth = verify_check_given_host(CUSS &ob->hosts_require_auth, host);
1600 #ifndef DISABLE_PIPE_CONNECT
1601 unsigned short authbits = tls_out.active.sock >= 0
1602 ? sx->ehlo_resp.crypted_auths : sx->ehlo_resp.cleartext_auths;
1604 uschar * fail_reason = US"server did not advertise AUTH support";
1606 f.smtp_authenticated = FALSE;
1607 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1610 regex_AUTH = regex_must_compile(AUTHS_REGEX, MCS_NOFLAGS, TRUE);
1612 /* Is the server offering AUTH? */
1616 #ifndef DISABLE_PIPE_CONNECT
1617 sx->early_pipe_active ? authbits
1620 regex_match_and_setup(regex_AUTH, sx->buffer, 0, -1)
1623 uschar * names = NULL;
1624 expand_nmax = -1; /* reset */
1626 #ifndef DISABLE_PIPE_CONNECT
1627 if (!sx->early_pipe_active)
1629 names = string_copyn(expand_nstring[1], expand_nlength[1]);
1631 /* Must not do this check until after we have saved the result of the
1632 regex match above as the check could be another RE. */
1634 if ( require_auth == OK
1635 || verify_check_given_host(CUSS &ob->hosts_try_auth, host) == OK)
1637 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1638 fail_reason = US"no common mechanisms were found";
1640 #ifndef DISABLE_PIPE_CONNECT
1641 if (sx->early_pipe_active)
1643 /* Scan our authenticators (which support use by a client and were offered
1644 by the server (checked at cache-write time)), not suppressed by
1645 client_condition. If one is found, attempt to authenticate by calling its
1646 client function. We are limited to supporting up to 16 authenticator
1647 public-names by the number of bits in a short. */
1653 for (bitnum = 0, au = auths;
1654 !f.smtp_authenticated && au && bitnum < 16;
1655 bitnum++, au = au->next) if (authbits & BIT(bitnum))
1657 if ( au->client_condition
1658 && !expand_check_condition(au->client_condition, au->name,
1659 US"client authenticator"))
1661 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1662 au->name, "client_condition is false");
1666 /* Found data for a listed mechanism. Call its client entry. Set
1667 a flag in the outblock so that data is overwritten after sending so
1668 that reflections don't show it. */
1670 fail_reason = US"authentication attempt(s) failed";
1672 if ((rc = try_authenticator(sx, au)) != OK)
1679 /* Scan the configured authenticators looking for one which is configured
1680 for use as a client, which is not suppressed by client_condition, and
1681 whose name matches an authentication mechanism supported by the server.
1682 If one is found, attempt to authenticate by calling its client function.
1685 for (auth_instance * au = auths; !f.smtp_authenticated && au; au = au->next)
1690 || ( au->client_condition
1691 && !expand_check_condition(au->client_condition, au->name,
1692 US"client authenticator")))
1694 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1696 (au->client)? "client_condition is false" :
1697 "not configured as a client");
1701 /* Loop to scan supported server mechanisms */
1705 int len = Ustrlen(au->public_name);
1708 while (isspace(*p)) p++;
1710 if (strncmpic(au->public_name, p, len) != 0 ||
1711 (p[len] != 0 && !isspace(p[len])))
1713 while (*p != 0 && !isspace(*p)) p++;
1717 /* Found data for a listed mechanism. Call its client entry. Set
1718 a flag in the outblock so that data is overwritten after sending so
1719 that reflections don't show it. */
1721 fail_reason = US"authentication attempt(s) failed";
1723 if ((rc = try_authenticator(sx, au)) != OK)
1726 break; /* If not authenticated, try next authenticator */
1727 } /* Loop for scanning supported server mechanisms */
1728 } /* Loop for further authenticators */
1732 /* If we haven't authenticated, but are required to, give up. */
1734 if (require_auth == OK && !f.smtp_authenticated)
1736 #ifndef DISABLE_PIPE_CONNECT
1737 invalidate_ehlo_cache_entry(sx);
1739 set_errno_nohost(sx->addrlist, ERRNO_AUTHFAIL,
1740 string_sprintf("authentication required but %s", fail_reason), DEFER,
1741 FALSE, &sx->delivery_start);
1749 /* Construct AUTH appendix string for MAIL TO */
1752 sx context for smtp connection
1753 p point in sx->buffer to build string
1754 addrlist chain of potential addresses to deliver
1756 Globals f.smtp_authenticated
1757 client_authenticated_sender
1758 Return True on error, otherwise buffer has (possibly empty) terminated string
1762 smtp_mail_auth_str(smtp_context * sx, uschar * p, address_item * addrlist)
1764 smtp_transport_options_block * ob = sx->conn_args.ob;
1765 uschar * local_authenticated_sender = authenticated_sender;
1768 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n",
1769 authenticated_sender, ob->authenticated_sender, f.smtp_authenticated?"Y":"N");
1772 if (ob->authenticated_sender)
1774 uschar * new = expand_string(ob->authenticated_sender);
1777 if (!f.expand_string_forcedfail)
1779 uschar *message = string_sprintf("failed to expand "
1780 "authenticated_sender: %s", expand_string_message);
1781 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
1786 local_authenticated_sender = new;
1789 /* Add the authenticated sender address if present */
1791 if ( (f.smtp_authenticated || ob->authenticated_sender_force)
1792 && local_authenticated_sender)
1794 string_format_nt(p, sizeof(sx->buffer) - (p-sx->buffer), " AUTH=%s",
1795 auth_xtextencode(local_authenticated_sender,
1796 Ustrlen(local_authenticated_sender)));
1797 client_authenticated_sender = string_copy(local_authenticated_sender);
1807 typedef struct smtp_compare_s
1809 const uschar * current_sender_address;
1810 struct transport_instance * tblock;
1814 /* Create a unique string that identifies this message, it is based on
1815 sender_address, helo_data and tls_certificate if enabled.
1819 smtp_local_identity(const uschar * sender, struct transport_instance * tblock)
1821 address_item * addr1;
1822 uschar * if1 = US"";
1823 uschar * helo1 = US"";
1825 uschar * tlsc1 = US"";
1827 const uschar * save_sender_address = sender_address;
1828 uschar * local_identity = NULL;
1829 smtp_transport_options_block * ob = SOB tblock->options_block;
1831 sender_address = sender;
1833 addr1 = deliver_make_addr (sender, TRUE);
1834 deliver_set_expansions(addr1);
1837 if1 = expand_string(ob->interface);
1840 helo1 = expand_string(ob->helo_data);
1843 if (ob->tls_certificate)
1844 tlsc1 = expand_string(ob->tls_certificate);
1845 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1847 local_identity = string_sprintf ("%s^%s", if1, helo1);
1850 deliver_set_expansions(NULL);
1851 sender_address = save_sender_address;
1853 return local_identity;
1858 /* This routine is a callback that is called from transport_check_waiting.
1859 This function will evaluate the incoming message versus the previous
1860 message. If the incoming message is using a different local identity then
1861 we will veto this new message. */
1864 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1866 uschar * message_local_identity,
1867 * current_local_identity,
1868 * new_sender_address;
1870 current_local_identity =
1871 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1873 if (!(new_sender_address = spool_sender_from_msgid(message_id)))
1877 message_local_identity =
1878 smtp_local_identity(new_sender_address, s_compare->tblock);
1880 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1886 ehlo_response(uschar * buf, unsigned checks)
1888 PCRE2_SIZE bsize = Ustrlen(buf);
1889 pcre2_match_data * md = pcre2_match_data_create(1, pcre_gen_ctx);
1891 /* debug_printf("%s: check for 0x%04x\n", __FUNCTION__, checks); */
1894 if ( checks & OPTION_TLS
1895 && pcre2_match(regex_STARTTLS,
1896 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1898 checks &= ~OPTION_TLS;
1900 if ( checks & OPTION_IGNQ
1901 && pcre2_match(regex_IGNOREQUOTA,
1902 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1903 checks &= ~OPTION_IGNQ;
1905 if ( checks & OPTION_CHUNKING
1906 && pcre2_match(regex_CHUNKING,
1907 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1908 checks &= ~OPTION_CHUNKING;
1910 #ifndef DISABLE_PRDR
1911 if ( checks & OPTION_PRDR
1912 && pcre2_match(regex_PRDR,
1913 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1915 checks &= ~OPTION_PRDR;
1918 if ( checks & OPTION_UTF8
1919 && pcre2_match(regex_UTF8,
1920 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1922 checks &= ~OPTION_UTF8;
1924 if ( checks & OPTION_DSN
1925 && pcre2_match(regex_DSN,
1926 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1927 checks &= ~OPTION_DSN;
1929 if ( checks & OPTION_PIPE
1930 && pcre2_match(regex_PIPELINING,
1931 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1932 checks &= ~OPTION_PIPE;
1934 if ( checks & OPTION_SIZE
1935 && pcre2_match(regex_SIZE,
1936 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1937 checks &= ~OPTION_SIZE;
1939 #ifndef DISABLE_PIPE_CONNECT
1940 if ( checks & OPTION_EARLY_PIPE
1941 && pcre2_match(regex_EARLY_PIPE,
1942 (PCRE2_SPTR)buf, bsize, 0, PCRE_EOPT, md, pcre_gen_mtc_ctx) < 0)
1944 checks &= ~OPTION_EARLY_PIPE;
1946 /* pcre2_match_data_free(md); gen ctx needs no free */
1947 /* debug_printf("%s: found 0x%04x\n", __FUNCTION__, checks); */
1953 /* Callback for emitting a BDAT data chunk header.
1955 If given a nonzero size, first flush any buffered SMTP commands
1956 then emit the command.
1958 Reap previous SMTP command responses if requested, and always reap
1959 the response from a previous BDAT command.
1962 tctx transport context
1963 chunk_size value for SMTP BDAT command
1965 tc_chunk_last add LAST option to SMTP BDAT command
1966 tc_reap_prev reap response to previous SMTP commands
1970 DEFER TLS error on first read (EHLO-resp); errno set
1974 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1977 smtp_transport_options_block * ob = SOB tctx->tblock->options_block;
1978 smtp_context * sx = tctx->smtp_context;
1982 /* Write SMTP chunk header command. If not reaping responses, note that
1983 there may be more writes (like, the chunk data) done soon. */
1987 #ifndef DISABLE_PIPE_CONNECT
1988 BOOL new_conn = !!(sx->outblock.conn_args);
1990 if((cmd_count = smtp_write_command(sx,
1991 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1992 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1993 ) < 0) return ERROR;
1994 if (flags & tc_chunk_last)
1995 data_command = string_copy(big_buffer); /* Save for later error message */
1996 #ifndef DISABLE_PIPE_CONNECT
1997 /* That command write could have been the one that made the connection.
1998 Copy the fd from the client conn ctx (smtp transport specific) to the
1999 generic transport ctx. */
2002 tctx->u.fd = sx->outblock.cctx->sock;
2006 prev_cmd_count = cmd_count += sx->cmd_count;
2008 /* Reap responses for any previous, but not one we just emitted */
2012 if (sx->pending_BDAT)
2015 if (flags & tc_reap_prev && prev_cmd_count > 0)
2017 DEBUG(D_transport) debug_printf("look for %d responses"
2018 " for previous pipelined cmds\n", prev_cmd_count);
2020 switch(sync_responses(sx, prev_cmd_count, 0))
2022 case RESP_BIT_HAD_2XX: /* OK */
2023 case RESP_HAD_2_AND_5: sx->good_RCPT = TRUE; /* OK & progress made */
2024 case RESP_BIT_HAD_5XX: sx->completed_addr = TRUE; /* progress made */
2025 case RESP_NOERROR: break; /* No 2xx or 5xx, but no probs */
2027 case RESP_EHLO_ERR_TLS:errno = ERRNO_TLSFAILURE;
2029 #ifndef DISABLE_PIPE_CONNECT
2030 case RESP_EPIPE_EHLO_ERR: /* non-2xx for pipelined banner or EHLO */
2032 case RESP_RCPT_TIMEO: /* Timeout on RCPT */
2033 default: return ERROR;/* I/O error, or any MAIL/DATA error */
2036 if (!sx->pending_BDAT)
2037 pipelining_active = FALSE;
2040 /* Reap response for an outstanding BDAT */
2042 if (sx->pending_BDAT)
2044 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
2046 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
2047 ob->command_timeout))
2049 if (errno == 0 && sx->buffer[0] == '4')
2051 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
2052 sx->addrlist->more_errno |=
2053 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2058 sx->pending_BDAT = FALSE;
2059 pipelining_active = FALSE;
2061 else if (chunk_size > 0)
2062 sx->pending_BDAT = TRUE;
2065 sx->cmd_count = cmd_count;
2073 check_force_dane_conn(smtp_context * sx, smtp_transport_options_block * ob)
2076 if( sx->dane_required
2077 || verify_check_given_host(CUSS &ob->hosts_try_dane, sx->conn_args.host) == OK
2079 switch (rc = tlsa_lookup(sx->conn_args.host, &sx->conn_args.tlsa_dnsa, sx->dane_required))
2081 case OK: sx->conn_args.dane = TRUE;
2082 ob->tls_tempfail_tryclear = FALSE; /* force TLS */
2083 ob->tls_sni = sx->conn_args.host->name; /* force SNI */
2085 case FAIL_FORCED: break;
2086 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2087 string_sprintf("DANE error: tlsa lookup %s",
2089 rc, FALSE, &sx->delivery_start);
2090 # ifndef DISABLE_EVENT
2091 (void) event_raise(sx->conn_args.tblock->event_action,
2092 US"dane:fail", sx->dane_required
2093 ? US"dane-required" : US"dnssec-invalid",
2103 /*************************************************
2104 * Make connection for given message *
2105 *************************************************/
2109 sx connection context
2110 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2111 a second attempt after TLS initialization fails
2113 Returns: OK - the connection was made and the delivery attempted;
2114 fd is set in the conn context, tls_out set up.
2115 DEFER - the connection could not be made, or something failed
2116 while setting up the SMTP session, or there was a
2117 non-message-specific error, such as a timeout.
2118 ERROR - helo_data or add_headers or authenticated_sender is
2119 specified for this transport, and the string failed
2123 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
2125 smtp_transport_options_block * ob = sx->conn_args.tblock->options_block;
2126 BOOL pass_message = FALSE;
2127 uschar * message = NULL;
2130 uschar * tls_errstr;
2133 /* Many lines of clearing individual elements of *sx that used to
2134 be here have been replaced by a full memset to zero (de41aff051).
2135 There are two callers, this file and verify.c . Now we only set
2136 up nonzero elements. */
2138 sx->conn_args.ob = ob;
2140 sx->lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
2141 sx->smtps = strcmpic(ob->protocol, US"smtps") == 0;
2142 sx->send_rset = TRUE;
2143 sx->send_quit = TRUE;
2144 sx->setting_up = TRUE;
2146 sx->dsn_all_lasthop = TRUE;
2149 verify_check_given_host(CUSS &ob->hosts_require_dane, sx->conn_args.host) == OK;
2152 if ((sx->max_mail = sx->conn_args.tblock->connection_max_messages) == 0)
2153 sx->max_mail = UNLIMITED_ADDRS;
2154 sx->max_rcpt = expand_max_rcpt(sx->conn_args.tblock->max_addresses);
2155 sx->igquotstr = US"";
2156 if (!sx->helo_data) sx->helo_data = ob->helo_data;
2158 smtp_command = US"initial connection";
2160 /* Set up the buffer for reading SMTP response packets. */
2162 sx->inblock.buffer = sx->inbuffer;
2163 sx->inblock.buffersize = sizeof(sx->inbuffer);
2164 sx->inblock.ptr = sx->inbuffer;
2165 sx->inblock.ptrend = sx->inbuffer;
2167 /* Set up the buffer for holding SMTP commands while pipelining */
2169 sx->outblock.buffer = sx->outbuffer;
2170 sx->outblock.buffersize = sizeof(sx->outbuffer);
2171 sx->outblock.ptr = sx->outbuffer;
2173 /* Reset the parameters of a TLS session. */
2176 tls_out.cipher = NULL; /* the one we may use for this transport */
2177 tls_out.ourcert = NULL;
2178 tls_out.peercert = NULL;
2179 tls_out.peerdn = NULL;
2183 tls_out.ocsp = OCSP_NOT_REQ;
2184 #ifndef DISABLE_TLS_RESUME
2185 tls_out.resumption = 0;
2189 /* Flip the legacy TLS-related variables over to the outbound set in case
2190 they're used in the context of the transport. Don't bother resetting
2191 afterward (when being used by a transport) as we're in a subprocess.
2192 For verify, unflipped once the callout is dealt with */
2194 tls_modify_variables(&tls_out);
2199 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
2200 DEFER, FALSE, &sx->delivery_start);
2205 /* If we have a proxied TLS connection, check usability for this message */
2207 if (continue_hostname && continue_proxy_cipher)
2210 const uschar * sni = US"";
2212 # ifdef SUPPORT_DANE
2213 /* Check if the message will be DANE-verified; if so force TLS and its SNI */
2215 tls_out.dane_verified = FALSE;
2216 smtp_port_for_connect(sx->conn_args.host, sx->port);
2217 if ( sx->conn_args.host->dnssec == DS_YES
2218 && (rc = check_force_dane_conn(sx, ob)) != OK
2223 /* If the SNI or the DANE status required for the new message differs from the
2224 existing conn drop the connection to force a new one. */
2226 if (ob->tls_sni && !(sni = expand_cstring(ob->tls_sni)))
2227 log_write(0, LOG_MAIN|LOG_PANIC,
2228 "<%s>: failed to expand transport's tls_sni value: %s",
2229 sx->addrlist->address, expand_string_message);
2231 # ifdef SUPPORT_DANE
2232 if ( (continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni)
2233 && continue_proxy_dane == sx->conn_args.dane)
2235 tls_out.sni = US sni;
2236 if ((tls_out.dane_verified = continue_proxy_dane))
2237 sx->conn_args.host->dnssec = DS_YES;
2240 if ((continue_proxy_sni ? (Ustrcmp(continue_proxy_sni, sni) == 0) : !*sni))
2241 tls_out.sni = US sni;
2246 debug_printf("Closing proxied-TLS connection due to SNI mismatch\n");
2248 smtp_debug_cmd(US"QUIT", 0);
2249 write(0, "QUIT\r\n", 6);
2251 continue_hostname = continue_proxy_cipher = NULL;
2252 f.continue_more = FALSE;
2253 continue_sequence = 1; /* Unfortunately, this process cannot affect success log
2254 which is done by delivery proc. Would have to pass this
2255 back through reporting pipe. */
2258 #endif /*!DISABLE_TLS*/
2260 /* Make a connection to the host if this isn't a continued delivery, and handle
2261 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
2262 specially so they can be identified for retries. */
2264 if (!continue_hostname)
2267 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->conn_args.interface, sx->port);
2269 /* Arrange to report to calling process this is a new connection */
2271 clearflag(sx->first_addr, af_cont_conn);
2272 setflag(sx->first_addr, af_new_conn);
2274 /* Get the actual port the connection will use, into sx->conn_args.host */
2276 smtp_port_for_connect(sx->conn_args.host, sx->port);
2279 /* Do TLSA lookup for DANE */
2281 tls_out.dane_verified = FALSE;
2282 tls_out.tlsa_usage = 0;
2284 if (sx->conn_args.host->dnssec == DS_YES)
2287 if ((rc = check_force_dane_conn(sx, ob)) != OK)
2290 else if (sx->dane_required)
2292 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
2293 string_sprintf("DANE error: %s lookup not DNSSEC", sx->conn_args.host->name),
2294 FAIL, FALSE, &sx->delivery_start);
2295 # ifndef DISABLE_EVENT
2296 (void) event_raise(sx->conn_args.tblock->event_action,
2297 US"dane:fail", US"dane-required", NULL);
2304 /* Make the TCP connection */
2306 sx->cctx.tls_ctx = NULL;
2307 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2308 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2309 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom =
2311 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
2312 #ifndef DISABLE_CLIENT_CMD_LOG
2313 client_cmd_log = NULL;
2316 #ifndef DISABLE_PIPE_CONNECT
2317 if ( verify_check_given_host(CUSS &ob->hosts_pipe_connect,
2318 sx->conn_args.host) == OK)
2320 /* We don't find out the local ip address until the connect, so if
2321 the helo string might use it avoid doing early-pipelining. */
2324 || sx->conn_args.interface
2325 || !Ustrstr(sx->helo_data, "$sending_ip_address")
2326 || Ustrstr(sx->helo_data, "def:sending_ip_address")
2329 sx->early_pipe_ok = TRUE;
2330 if ( read_ehlo_cache_entry(sx)
2331 && sx->ehlo_resp.cleartext_features & OPTION_EARLY_PIPE)
2334 debug_printf("Using cached cleartext PIPECONNECT\n");
2335 sx->early_pipe_active = TRUE;
2336 sx->peer_offered = sx->ehlo_resp.cleartext_features;
2339 else DEBUG(D_transport)
2340 debug_printf("helo needs $sending_ip_address; avoid early-pipelining\n");
2343 if (sx->early_pipe_active)
2345 sx->outblock.conn_args = &sx->conn_args;
2346 (void) smtp_boundsock(&sx->conn_args);
2351 blob lazy_conn = {.data = NULL};
2352 /* For TLS-connect, a TFO lazy-connect is useful since the Client Hello
2353 can go on the TCP SYN. */
2355 if ((sx->cctx.sock = smtp_connect(&sx->conn_args,
2356 sx->smtps ? &lazy_conn : NULL)) < 0)
2358 set_errno_nohost(sx->addrlist,
2359 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
2360 sx->verify ? US strerror(errno) : NULL,
2361 DEFER, FALSE, &sx->delivery_start);
2362 sx->send_quit = FALSE;
2366 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, TCP_QUICKACK, US &off,
2370 /* Expand the greeting message while waiting for the initial response. (Makes
2371 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
2372 delayed till here so that $sending_ip_address and $sending_port are set.
2373 Those will be known even for a TFO lazy-connect, having been set by the bind().
2374 For early-pipe, we are ok if binding to a local interface; otherwise (if
2375 $sending_ip_address is seen in helo_data) we disabled early-pipe above. */
2378 if (!(sx->helo_data = expand_string(sx->helo_data)))
2380 log_write(0, LOG_MAIN|LOG_PANIC,
2381 "<%s>: failed to expand transport's helo_data value for callout: %s",
2382 sx->addrlist->address, expand_string_message);
2387 expand_string_message = NULL;
2388 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
2389 &expand_string_message)),
2390 expand_string_message)
2392 log_write(0, LOG_MAIN|LOG_PANIC,
2393 "<%s>: failed to expand transport's helo_data value for callout: %s",
2394 sx->addrlist->address, expand_string_message);
2396 sx->helo_data = NULL;
2400 /* The first thing is to wait for an initial OK response. The dreaded "goto"
2401 is nevertheless a reasonably clean way of programming this kind of logic,
2402 where you want to escape on any error. */
2406 #ifndef DISABLE_PIPE_CONNECT
2407 if (sx->early_pipe_active)
2409 sx->pending_BANNER = TRUE; /* sync_responses() must eventually handle */
2410 sx->outblock.cmd_count = 1;
2415 if (!smtp_reap_banner(sx))
2416 goto RESPONSE_FAILED;
2419 #ifndef DISABLE_EVENT
2422 lookup_dnssec_authenticated = sx->conn_args.host->dnssec==DS_YES ? US"yes"
2423 : sx->conn_args.host->dnssec==DS_NO ? US"no" : NULL;
2424 s = event_raise(sx->conn_args.tblock->event_action, US"smtp:connect", sx->buffer, NULL);
2427 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
2428 string_sprintf("deferred by smtp:connect event expansion: %s", s),
2429 DEFER, FALSE, &sx->delivery_start);
2436 /* Now check if the helo_data expansion went well, and sign off cleanly if
2441 message = string_sprintf("failed to expand helo_data: %s",
2442 expand_string_message);
2443 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2449 /** Debugging without sending a message
2450 sx->addrlist->transport_return = DEFER;
2454 /* Errors that occur after this point follow an SMTP command, which is
2455 left in big_buffer by smtp_write_command() for use in error messages. */
2457 smtp_command = big_buffer;
2459 /* Tell the remote who we are...
2461 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
2462 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
2463 greeting is of this form. The assumption was that the far end supports it
2464 properly... but experience shows that there are some that give 5xx responses,
2465 even though the banner includes "ESMTP" (there's a bloody-minded one that
2466 says "ESMTP not spoken here"). Cope with that case.
2468 September 2000: Time has passed, and it seems reasonable now to always send
2469 EHLO at the start. It is also convenient to make the change while installing
2472 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
2473 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
2474 would be no way to send out the mails, so there is now a host list
2475 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
2476 PIPELINING problem as well. Maybe it can also be useful to cure other
2477 problems with broken servers.
2479 Exim originally sent "Helo" at this point and ran for nearly a year that way.
2480 Then somebody tried it with a Microsoft mailer... It seems that all other
2481 mailers use upper case for some reason (the RFC is quite clear about case
2482 independence) so, for peace of mind, I gave in. */
2484 sx->esmtp = verify_check_given_host(CUSS &ob->hosts_avoid_esmtp, sx->conn_args.host) != OK;
2486 /* Alas; be careful, since this goto is not an error-out, so conceivably
2487 we might set data between here and the target which we assume to exist
2488 and be usable. I can see this coming back to bite us. */
2494 smtp_peer_options |= OPTION_TLS;
2495 suppress_tls = FALSE;
2496 ob->tls_tempfail_tryclear = FALSE;
2497 smtp_command = US"SSL-on-connect";
2499 # ifndef DISABLE_TLS_RESUME
2500 /* Having no EHLO response yet, cannot peek there for a servername to detect
2501 an LB. Call this anyway, so that a dummy host_name_extract option value can
2502 force resumption attempts. */
2504 if (!(s = ob->host_name_extract)) s = US"never-LB";
2505 ehlo_response_lbserver(sx, s);
2513 if (smtp_write_command(sx,
2514 #ifndef DISABLE_PIPE_CONNECT
2515 sx->early_pipe_active ? SCMD_BUFFER :
2518 "%s %s\r\n", sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
2520 sx->esmtp_sent = TRUE;
2522 #ifndef DISABLE_PIPE_CONNECT
2523 if (sx->early_pipe_active)
2525 sx->pending_EHLO = TRUE;
2527 /* If we have too many authenticators to handle and might need to AUTH
2528 for this transport, pipeline no further as we will need the
2529 list of auth methods offered. Reap the banner and EHLO. */
2531 if ( (ob->hosts_require_auth || ob->hosts_try_auth)
2532 && f.smtp_in_early_pipe_no_auth)
2534 DEBUG(D_transport) debug_printf("may need to auth, so pipeline no further\n");
2535 if (smtp_write_command(sx, SCMD_FLUSH, NULL) < 0)
2537 if (sync_responses(sx, 2, 0) != RESP_NOERROR)
2540 debug_printf("failed reaping pipelined cmd responses\n");
2541 goto RESPONSE_FAILED;
2543 sx->early_pipe_active = FALSE;
2548 if (!smtp_reap_ehlo(sx))
2549 goto RESPONSE_FAILED;
2553 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2555 #ifndef DISABLE_PIPE_CONNECT
2556 if (!sx->early_pipe_active)
2561 int n = sizeof(sx->buffer);
2562 uschar * rsp = sx->buffer;
2564 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer) + 1) < sizeof(sx->buffer)/2)
2565 { rsp = sx->buffer + n; n = sizeof(sx->buffer) - n; }
2567 if (smtp_write_command(sx, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
2569 good_response = smtp_read_response(sx, rsp, n, '2', ob->command_timeout);
2570 #ifdef EXPERIMENTAL_DSN_INFO
2571 sx->helo_response = string_copy(rsp);
2575 /* Handle special logging for a closed connection after HELO
2576 when had previously sent EHLO */
2578 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
2580 errno = ERRNO_SMTPCLOSED;
2581 goto EHLOHELO_FAILED;
2583 memmove(sx->buffer, rsp, Ustrlen(rsp));
2584 goto RESPONSE_FAILED;
2588 if (sx->esmtp || sx->lmtp)
2590 #ifndef DISABLE_PIPE_CONNECT
2591 if (!sx->early_pipe_active)
2596 sx->peer_offered = ehlo_response(sx->buffer,
2597 OPTION_TLS /* others checked later */
2598 #ifndef DISABLE_PIPE_CONNECT
2599 | (sx->early_pipe_ok
2601 | OPTION_CHUNKING | OPTION_PRDR | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2610 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2611 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
2613 ehlo_response_limits_read(sx);
2614 ehlo_response_limits_apply(sx);
2617 #ifndef DISABLE_PIPE_CONNECT
2618 if (sx->early_pipe_ok)
2620 sx->ehlo_resp.cleartext_features = sx->peer_offered;
2622 if ( (sx->peer_offered & (OPTION_PIPE | OPTION_EARLY_PIPE))
2623 == (OPTION_PIPE | OPTION_EARLY_PIPE))
2625 DEBUG(D_transport) debug_printf("PIPECONNECT usable in future for this IP\n");
2626 sx->ehlo_resp.cleartext_auths = study_ehlo_auths(sx);
2627 write_ehlo_cache_entry(sx);
2631 #ifndef DISABLE_TLS_RESUME
2632 if (!(s = ob->host_name_extract)) s = HNE_DEFAULT;
2633 ehlo_response_lbserver(sx, s);
2637 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
2640 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
2645 /* For continuing deliveries down the same channel, having re-exec'd the socket
2646 is the standard input; for a socket held open from verify it is recorded
2647 in the cutthrough context block. Either way we don't need to redo EHLO here
2648 (but may need to do so for TLS - see below).
2649 Set up the pointer to where subsequent commands will be left, for
2650 error messages. Note that smtp_peer_options will have been
2651 set from the command line if they were set in the process that passed the
2654 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
2655 as the continue goes via transport_pass_socket() and doublefork and exec.
2656 It does not wait. Unclear how we keep separate host's responses
2657 separate - we could match up by host ip+port as a bodge. */
2661 if (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only)
2663 sx->cctx = cutthrough.cctx;
2664 sx->conn_args.host->port = sx->port = cutthrough.host.port;
2668 sx->cctx.sock = 0; /* stdin */
2669 sx->cctx.tls_ctx = NULL;
2670 smtp_port_for_connect(sx->conn_args.host, sx->port); /* Record the port that was used */
2672 sx->inblock.cctx = sx->outblock.cctx = &sx->cctx;
2673 smtp_command = big_buffer;
2674 sx->peer_offered = smtp_peer_options;
2675 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2676 /* Limits passed by cmdline over exec. */
2677 ehlo_limits_apply(sx,
2678 sx->peer_limit_mail = continue_limit_mail,
2679 sx->peer_limit_rcpt = continue_limit_rcpt,
2680 sx->peer_limit_rcptdom = continue_limit_rcptdom);
2682 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
2684 /* For a continued connection with TLS being proxied for us, or a
2685 held-open verify connection with TLS, nothing more to do. */
2687 if ( continue_proxy_cipher
2688 || (cutthrough.cctx.sock >= 0 && cutthrough.callout_hold_only
2689 && cutthrough.is_tls)
2692 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2693 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
2694 continue_proxy_cipher ? "proxied" : "verify conn with");
2697 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
2700 /* If TLS is available on this connection, whether continued or not, attempt to
2701 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
2702 send another EHLO - the server may give a different answer in secure mode. We
2703 use a separate buffer for reading the response to STARTTLS so that if it is
2704 negative, the original EHLO data is available for subsequent analysis, should
2705 the client not be required to use TLS. If the response is bad, copy the buffer
2706 for error analysis. */
2709 if ( smtp_peer_options & OPTION_TLS
2711 && verify_check_given_host(CUSS &ob->hosts_avoid_tls, sx->conn_args.host) != OK
2713 || verify_check_given_host(CUSS &ob->hosts_verify_avoid_tls, sx->conn_args.host) != OK
2716 uschar buffer2[4096];
2718 if (smtp_write_command(sx, SCMD_FLUSH, "STARTTLS\r\n") < 0)
2721 #ifndef DISABLE_PIPE_CONNECT
2722 /* If doing early-pipelining reap the banner and EHLO-response but leave
2723 the response for the STARTTLS we just sent alone. On fail, assume wrong
2724 cached capability and retry with the pipelining disabled. */
2726 if (sx->early_pipe_active)
2728 if (sync_responses(sx, 2, 0) != RESP_NOERROR)
2731 debug_printf("failed reaping pipelined cmd responses\n");
2732 close(sx->cctx.sock);
2734 sx->early_pipe_active = FALSE;
2735 goto PIPE_CONNECT_RETRY;
2740 /* If there is an I/O error, transmission of this message is deferred. If
2741 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
2742 false, we also defer. However, if there is a temporary rejection of STARTTLS
2743 and tls_tempfail_tryclear is true, or if there is an outright rejection of
2744 STARTTLS, we carry on. This means we will try to send the message in clear,
2745 unless the host is in hosts_require_tls (tested below). */
2747 if (!smtp_read_response(sx, buffer2, sizeof(buffer2), '2', ob->command_timeout))
2751 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
2754 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
2755 sx->buffer[sizeof(sx->buffer)-1] = '\0';
2756 goto RESPONSE_FAILED;
2760 /* STARTTLS accepted: try to negotiate a TLS session. */
2765 sx->conn_args.sending_ip_address = sending_ip_address;
2766 if (!tls_client_start(&sx->cctx, &sx->conn_args, sx->addrlist, &tls_out, &tls_errstr))
2768 /* TLS negotiation failed; give an error. From outside, this function may
2769 be called again to try in clear on a new connection, if the options permit
2770 it for this host. */
2772 DEBUG(D_tls) debug_printf("TLS session fail: %s\n", tls_errstr);
2774 # ifdef SUPPORT_DANE
2775 if (sx->conn_args.dane)
2777 log_write(0, LOG_MAIN,
2778 "DANE attempt failed; TLS connection to %s [%s]: %s",
2779 sx->conn_args.host->name, sx->conn_args.host->address, tls_errstr);
2780 # ifndef DISABLE_EVENT
2781 (void) event_raise(sx->conn_args.tblock->event_action,
2782 US"dane:fail", US"validation-failure", NULL); /* could do with better detail */
2787 errno = ERRNO_TLSFAILURE;
2788 message = string_sprintf("TLS session: %s", tls_errstr);
2789 sx->send_quit = FALSE;
2792 sx->send_tlsclose = TRUE;
2794 /* TLS session is set up. Check the inblock fill level. If there is
2795 content then as we have not yet done a tls read it must have arrived before
2796 the TLS handshake, in-clear. That violates the sync requirement of the
2797 STARTTLS RFC, so fail. */
2799 if (sx->inblock.ptr != sx->inblock.ptrend)
2803 int i = sx->inblock.ptrend - sx->inblock.ptr;
2804 debug_printf("unused data in input buffer after ack for STARTTLS:\n"
2806 i > 100 ? 100 : i, sx->inblock.ptr, i > 100 ? "..." : "");
2808 tls_errstr = US"synch error before connect";
2809 goto TLS_CONN_FAILED;
2812 smtp_peer_options_wrap = smtp_peer_options;
2813 for (address_item * addr = sx->addrlist; addr; addr = addr->next)
2814 if (addr->transport_return == PENDING_DEFER)
2816 addr->cipher = tls_out.cipher;
2817 addr->ourcert = tls_out.ourcert;
2818 addr->peercert = tls_out.peercert;
2819 addr->peerdn = tls_out.peerdn;
2820 addr->ocsp = tls_out.ocsp;
2821 addr->tlsver = tls_out.ver;
2826 /* if smtps, we'll have smtp_command set to something else; always safe to
2828 smtp_command = big_buffer;
2830 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
2831 helo_data is null, we are dealing with a connection that was passed from
2832 another process, and so we won't have expanded helo_data above. We have to
2833 expand it here. $sending_ip_address and $sending_port are set up right at the
2834 start of the Exim process (in exim.c). */
2836 if (tls_out.active.sock >= 0)
2838 uschar * greeting_cmd;
2840 if (!sx->helo_data && !(sx->helo_data = expand_string(ob->helo_data)))
2842 uschar *message = string_sprintf("failed to expand helo_data: %s",
2843 expand_string_message);
2844 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
2849 #ifndef DISABLE_PIPE_CONNECT
2850 /* For SMTPS there is no cleartext early-pipe; use the crypted permission bit.
2851 We're unlikely to get the group sent and delivered before the server sends its
2852 banner, but it's still worth sending as a group.
2853 For STARTTLS allow for cleartext early-pipe but no crypted early-pipe, but not
2856 if (sx->smtps ? sx->early_pipe_ok : sx->early_pipe_active)
2858 sx->peer_offered = sx->ehlo_resp.crypted_features;
2859 if ((sx->early_pipe_active =
2860 !!(sx->ehlo_resp.crypted_features & OPTION_EARLY_PIPE)))
2861 DEBUG(D_transport) debug_printf("Using cached crypted PIPECONNECT\n");
2864 #ifdef EXPERIMMENTAL_ESMTP_LIMITS
2865 /* As we are about to send another EHLO, forget any LIMITS received so far. */
2866 sx->peer_limit_mail = sx->peer_limit_rcpt = sx->peer_limit_rcptdom = 0;
2867 if ((sx->max_mail = sx->conn_args.tblock->connection_max_message) == 0)
2868 sx->max_mail = UNLIMITED_ADDRS;
2869 sx->max_rcpt = expand_max_rcpt(sx->conn_args.tblock->max_addresses);
2870 sx->single_rcpt_domain = FALSE;
2873 /* For SMTPS we need to wait for the initial OK response. */
2875 #ifndef DISABLE_PIPE_CONNECT
2876 if (sx->early_pipe_active)
2878 sx->pending_BANNER = TRUE;
2879 sx->outblock.cmd_count = 1;
2883 if (!smtp_reap_banner(sx))
2884 goto RESPONSE_FAILED;
2887 greeting_cmd = US"LHLO";
2889 greeting_cmd = US"EHLO";
2892 greeting_cmd = US"HELO";
2894 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2897 if (smtp_write_command(sx,
2898 #ifndef DISABLE_PIPE_CONNECT
2899 sx->early_pipe_active ? SCMD_BUFFER :
2902 "%s %s\r\n", greeting_cmd, sx->helo_data) < 0)
2905 #ifndef DISABLE_PIPE_CONNECT
2906 if (sx->early_pipe_active)
2907 sx->pending_EHLO = TRUE;
2911 if (!smtp_reap_ehlo(sx))
2914 /* The GnuTLS layer in Exim only spots a server-rejection of a client
2915 cert late, under TLS1.3 - which means here; the first time we try to
2916 receive crypted data. Treat it as if it was a connect-time failure.
2917 See also the early-pipe equivalent... which will be hard; every call
2918 to sync_responses will need to check the result.
2919 It would be nicer to have GnuTLS check the cert during the handshake.
2920 Can it do that, with all the flexibility we need? */
2922 tls_errstr = US"error on first read";
2923 goto TLS_CONN_FAILED;
2926 goto RESPONSE_FAILED;
2928 smtp_peer_options = 0;
2932 /* If the host is required to use a secure channel, ensure that we
2936 # ifdef SUPPORT_DANE
2937 || sx->conn_args.dane
2939 || verify_check_given_host(CUSS &ob->hosts_require_tls, sx->conn_args.host) == OK
2942 errno = ERRNO_TLSREQUIRED;
2943 message = string_sprintf("a TLS session is required, but %s",
2944 smtp_peer_options & OPTION_TLS
2945 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2946 # if defined(SUPPORT_DANE) && !defined(DISABLE_EVENT)
2947 if (sx->conn_args.dane)
2948 (void) event_raise(sx->conn_args.tblock->event_action, US"dane:fail",
2949 smtp_peer_options & OPTION_TLS
2950 ? US"validation-failure" /* could do with better detail */
2951 : US"starttls-not-supported",
2956 #endif /*DISABLE_TLS*/
2958 /* If TLS is active, we have just started it up and re-done the EHLO command,
2959 so its response needs to be analyzed. If TLS is not active and this is a
2960 continued session down a previously-used socket, we haven't just done EHLO, so
2963 if ( !continue_hostname
2965 || tls_out.active.sock >= 0
2969 if (sx->esmtp || sx->lmtp)
2971 #ifndef DISABLE_PIPE_CONNECT
2972 if (!sx->early_pipe_active)
2975 sx->peer_offered = ehlo_response(sx->buffer,
2977 #ifndef DISABLE_PIPE_CONNECT
2978 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2979 | OPTION_DSN | OPTION_PIPE | OPTION_SIZE
2980 | OPTION_CHUNKING | OPTION_PRDR | OPTION_UTF8
2981 | (tls_out.active.sock >= 0 ? OPTION_EARLY_PIPE : 0) /* not for lmtp */
2985 | (sx->lmtp && ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2988 # ifdef SUPPORT_I18N
2989 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2990 /*XXX if we hand peercaps on to continued-conn processes,
2991 must not depend on this addr */
2995 | (ob->size_addition >= 0 ? OPTION_SIZE : 0)
2998 #ifndef DISABLE_PIPE_CONNECT
2999 if (tls_out.active.sock >= 0)
3000 sx->ehlo_resp.crypted_features = sx->peer_offered;
3003 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3004 if (tls_out.active.sock >= 0 || !(sx->peer_offered & OPTION_TLS))
3006 ehlo_response_limits_read(sx);
3007 ehlo_response_limits_apply(sx);
3012 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
3013 lmtp_ignore_quota option was set. */
3015 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
3017 /* If the response to EHLO specified support for the SIZE parameter, note
3018 this, provided size_addition is non-negative. */
3020 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
3022 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
3023 the current host, esmtp will be false, so PIPELINING can never be used. If
3024 the current host matches hosts_avoid_pipelining, don't do it. */
3026 if ( sx->peer_offered & OPTION_PIPE
3027 && verify_check_given_host(CUSS &ob->hosts_avoid_pipelining, sx->conn_args.host) != OK)
3028 smtp_peer_options |= OPTION_PIPE;
3030 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
3031 smtp_peer_options & OPTION_PIPE ? "" : "not ");
3033 if ( sx->peer_offered & OPTION_CHUNKING
3034 && verify_check_given_host(CUSS &ob->hosts_try_chunking, sx->conn_args.host) == OK)
3035 smtp_peer_options |= OPTION_CHUNKING;
3037 if (smtp_peer_options & OPTION_CHUNKING)
3038 DEBUG(D_transport) debug_printf("CHUNKING usable\n");
3040 #ifndef DISABLE_PRDR
3041 if ( sx->peer_offered & OPTION_PRDR
3042 && verify_check_given_host(CUSS &ob->hosts_try_prdr, sx->conn_args.host) == OK)
3043 smtp_peer_options |= OPTION_PRDR;
3045 if (smtp_peer_options & OPTION_PRDR)
3046 DEBUG(D_transport) debug_printf("PRDR usable\n");
3049 /* Note if the server supports DSN */
3050 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
3051 DEBUG(D_transport) debug_printf("%susing DSN\n",
3052 sx->peer_offered & OPTION_DSN ? "" : "not ");
3054 #ifndef DISABLE_PIPE_CONNECT
3055 if ( sx->early_pipe_ok
3056 && !sx->early_pipe_active
3057 && tls_out.active.sock >= 0
3058 && smtp_peer_options & OPTION_PIPE
3059 && ( sx->ehlo_resp.cleartext_features | sx->ehlo_resp.crypted_features)
3060 & OPTION_EARLY_PIPE)
3062 DEBUG(D_transport) debug_printf("PIPECONNECT usable in future for this IP\n");
3063 sx->ehlo_resp.crypted_auths = study_ehlo_auths(sx);
3064 write_ehlo_cache_entry(sx);
3068 /* Note if the response to EHLO specifies support for the AUTH extension.
3069 If it has, check that this host is one we want to authenticate to, and do
3070 the business. The host name and address must be available when the
3071 authenticator's client driver is running. */
3073 switch (yield = smtp_auth(sx))
3075 default: goto SEND_QUIT;
3077 case FAIL_SEND: goto SEND_FAILED;
3078 case FAIL: goto RESPONSE_FAILED;
3082 sx->pipelining_used = pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
3084 /* The setting up of the SMTP call is now complete. Any subsequent errors are
3085 message-specific. */
3087 sx->setting_up = FALSE;
3090 if (sx->addrlist->prop.utf8_msg)
3094 /* If the transport sets a downconversion mode it overrides any set by ACL
3097 if ((s = ob->utf8_downconvert))
3099 if (!(s = expand_string(s)))
3101 message = string_sprintf("failed to expand utf8_downconvert: %s",
3102 expand_string_message);
3103 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, &sx->delivery_start);
3109 case '1': sx->addrlist->prop.utf8_downcvt = TRUE;
3110 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3112 case '0': sx->addrlist->prop.utf8_downcvt = FALSE;
3113 sx->addrlist->prop.utf8_downcvt_maybe = FALSE;
3115 case '-': if (s[1] == '1')
3117 sx->addrlist->prop.utf8_downcvt = FALSE;
3118 sx->addrlist->prop.utf8_downcvt_maybe = TRUE;
3124 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
3125 && !sx->addrlist->prop.utf8_downcvt_maybe;
3126 DEBUG(D_transport) if (!sx->utf8_needed)
3127 debug_printf("utf8: %s downconvert\n",
3128 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
3131 /* If this is an international message we need the host to speak SMTPUTF8 */
3132 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
3134 errno = ERRNO_UTF8_FWD;
3135 goto RESPONSE_FAILED;
3137 #endif /*SUPPORT_I18N*/
3146 if (errno == ECONNREFUSED) /* first-read error on a TFO conn */
3148 /* There is a testing facility for simulating a connection timeout, as I
3149 can't think of any other way of doing this. It converts a connection
3150 refused into a timeout if the timeout is set to 999999. This is done for
3151 a 3whs connection in ip_connect(), but a TFO connection does not error
3152 there - instead it gets ECONNREFUSED on the first data read. Tracking
3153 that a TFO really was done is too hard, or we would set a
3154 sx->pending_conn_done bit and test that in smtp_reap_banner() and
3155 smtp_reap_ehlo(). That would let us also add the conn-timeout to the
3158 if (f.running_in_test_harness && ob->connect_timeout == 999999)
3160 set_errno_nohost(sx->addrlist,
3161 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
3162 sx->verify ? US strerror(errno) : NULL,
3163 DEFER, FALSE, &sx->delivery_start);
3164 sx->send_quit = FALSE;
3168 /* really an error on an SMTP read */
3170 sx->send_quit = check_response(sx->conn_args.host, &errno, sx->addrlist->more_errno,
3171 sx->buffer, &code, &message, &pass_message);
3177 message = US string_sprintf("smtp send to %s [%s] failed: %s",
3178 sx->conn_args.host->name, sx->conn_args.host->address, strerror(errno));
3179 sx->send_quit = FALSE;
3185 message = string_sprintf("Remote host closed connection in response to %s"
3186 " (EHLO response was: %s)", smtp_command, sx->buffer);
3187 sx->send_quit = FALSE;
3191 /* This label is jumped to directly when a TLS negotiation has failed,
3192 or was not done for a host for which it is required. Values will be set
3193 in message and errno, and setting_up will always be true. Treat as
3194 a temporary error. */
3198 code = '4', yield = DEFER;
3202 /* The failure happened while setting up the call; see if the failure was
3203 a 5xx response (this will either be on connection, or following HELO - a 5xx
3204 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
3205 fail all addresses, as this host is never going to accept them. For other
3206 errors during setting up (timeouts or whatever), defer all addresses, and
3207 yield DEFER, so that the host is not tried again for a while.
3209 XXX This peeking for another host feels like a layering violation. We want
3210 to note the host as unusable, but down here we shouldn't know if this was
3211 the last host to try for the addr(list). Perhaps the upper layer should be
3212 the one to do set_errno() ? The problem is that currently the addr is where
3213 errno etc. are stashed, but until we run out of hosts to try the errors are
3214 host-specific. Maybe we should enhance the host_item definition? */
3217 sx->ok = FALSE; /* For when reached by GOTO */
3218 set_errno(sx->addrlist, errno, message,
3219 sx->conn_args.host->next
3223 || errno == ERRNO_UTF8_FWD
3227 errno == ECONNREFUSED ? NULL : sx->conn_args.host,
3228 #ifdef EXPERIMENTAL_DSN_INFO
3229 sx->smtp_greeting, sx->helo_response,
3231 &sx->delivery_start);
3238 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
3241 if (sx->cctx.tls_ctx)
3243 if (sx->send_tlsclose)
3245 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
3246 sx->send_tlsclose = FALSE;
3248 sx->cctx.tls_ctx = NULL;
3252 /* Close the socket, and return the appropriate value, first setting
3253 works because the NULL setting is passed back to the calling process, and
3254 remote_max_parallel is forced to 1 when delivering over an existing connection,
3257 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3260 shutdown(sx->cctx.sock, SHUT_WR);
3261 if (fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
3262 for (int i = 16; read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && i > 0;)
3263 i--; /* drain socket */
3264 sx->send_quit = FALSE;
3266 (void)close(sx->cctx.sock);
3269 #ifndef DISABLE_EVENT
3270 (void) event_raise(sx->conn_args.tblock->event_action, US"tcp:close", NULL, NULL);
3273 smtp_debug_cmd_report();
3274 continue_transport = NULL;
3275 continue_hostname = NULL;
3282 /* Create the string of options that will be appended to the MAIL FROM:
3283 in the connection context buffer */
3286 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
3288 uschar * p = sx->buffer;
3289 address_item * addr;
3294 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
3295 send it, adding something to the message size to allow for imprecision
3296 and things that get added en route. Exim keeps the number of lines
3297 in a message, so we can give an accurate value for the original message, but we
3298 need some additional to handle added headers. (Double "." characters don't get
3299 included in the count.) */
3301 if ( message_size > 0
3302 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
3304 /*XXX problem here under spool_files_wireformat?
3305 Or just forget about lines? Or inflate by a fixed proportion? */
3307 sprintf(CS p, " SIZE=%d", message_size+message_linecount+(SOB sx->conn_args.ob)->size_addition);
3311 #ifndef DISABLE_PRDR
3312 /* If it supports Per-Recipient Data Responses, and we have more than one recipient,
3315 sx->prdr_active = FALSE;
3316 if (smtp_peer_options & OPTION_PRDR)
3317 for (address_item * addr = addrlist; addr; addr = addr->next)
3318 if (addr->transport_return == PENDING_DEFER)
3320 for (addr = addr->next; addr; addr = addr->next)
3321 if (addr->transport_return == PENDING_DEFER)
3322 { /* at least two recipients to send */
3323 sx->prdr_active = TRUE;
3324 sprintf(CS p, " PRDR"); p += 5;
3332 /* If it supports internationalised messages, and this meesage need that,
3335 if ( sx->peer_offered & OPTION_UTF8
3336 && addrlist->prop.utf8_msg
3337 && !addrlist->prop.utf8_downcvt
3339 Ustrcpy(p, US" SMTPUTF8"), p += 9;
3342 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
3343 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
3344 addr && address_count < sx->max_rcpt; /*XXX maybe also || sx->single_rcpt_domain ? */
3345 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3348 if (!(addr->dsn_flags & rf_dsnlasthop))
3350 sx->dsn_all_lasthop = FALSE;
3355 /* Add any DSN flags to the mail command */
3357 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
3359 if (dsn_ret == dsn_ret_hdrs)
3360 { Ustrcpy(p, US" RET=HDRS"); p += 9; }
3361 else if (dsn_ret == dsn_ret_full)
3362 { Ustrcpy(p, US" RET=FULL"); p += 9; }
3366 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
3371 /* If an authenticated_sender override has been specified for this transport
3372 instance, expand it. If the expansion is forced to fail, and there was already
3373 an authenticated_sender for this message, the original value will be used.
3374 Other expansion failures are serious. An empty result is ignored, but there is
3375 otherwise no check - this feature is expected to be used with LMTP and other
3376 cases where non-standard addresses (e.g. without domains) might be required. */
3378 return smtp_mail_auth_str(sx, p, addrlist) ? ERROR : OK;
3383 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
3385 uschar * p = sx->buffer;
3388 /* Add any DSN flags to the rcpt command */
3390 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
3392 if (addr->dsn_flags & rf_dsnflags)
3396 Ustrcpy(p, US" NOTIFY=");
3398 for (int i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
3400 if (!first) *p++ = ',';
3402 Ustrcpy(p, rf_names[i]);
3407 if (addr->dsn_orcpt)
3409 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
3420 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
3421 -1 MAIL response error
3422 -2 any non-MAIL read i/o error
3423 -3 non-MAIL response timeout
3424 -4 internal error; channel still usable
3429 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
3431 address_item * addr;
3432 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3433 address_item * restart_addr = NULL;
3435 int address_count, pipe_limit;
3438 if (build_mailcmd_options(sx, sx->first_addr) != OK)
3444 /* From here until we send the DATA command, we can make use of PIPELINING
3445 if the server host supports it. The code has to be able to check the responses
3446 at any point, for when the buffer fills up, so we write it totally generally.
3447 When PIPELINING is off, each command written reports that it has flushed the
3450 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
3453 const uschar * s = sx->from_addr;
3455 uschar * errstr = NULL;
3457 /* If we must downconvert, do the from-address here. Remember we had to
3458 for the to-addresses (done below), and also (ugly) for re-doing when building
3459 the delivery log line. */
3461 if ( sx->addrlist->prop.utf8_msg
3462 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
3465 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
3467 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, &sx->delivery_start);
3471 setflag(sx->addrlist, af_utf8_downcvt);
3475 rc = smtp_write_command(sx, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
3476 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
3479 mail_command = string_copy(big_buffer); /* Save for later error message */
3483 case -1: /* Transmission error */
3486 case +1: /* Cmd was sent */
3487 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
3488 (SOB sx->conn_args.ob)->command_timeout))
3490 if (errno == 0 && sx->buffer[0] == '4')
3492 errno = ERRNO_MAIL4XX;
3493 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
3497 sx->pending_MAIL = FALSE;
3500 /* otherwise zero: command queued for pipeline */
3503 /* Pass over all the relevant recipient addresses for this host, which are the
3504 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
3505 several before we have to read the responses for those seen so far. This
3506 checking is done by a subroutine because it also needs to be done at the end.
3507 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
3508 the next one if not all are sent.
3510 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
3511 last address because we want to abort if any recipients have any kind of
3512 problem, temporary or permanent. We know that all recipient addresses will have
3513 the PENDING_DEFER status, because only one attempt is ever made, and we know
3514 that max_rcpt will be large, so all addresses will be done at once.
3516 For verify we flush the pipeline after any (the only) rcpt address. */
3518 for (addr = sx->first_addr, address_count = 0, pipe_limit = 100;
3519 addr && address_count < sx->max_rcpt;
3520 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
3524 const uschar * rcpt_addr;
3526 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3527 if ( sx->single_rcpt_domain /* restriction on domains */
3528 && address_count > 0 /* not first being sent */
3529 && Ustrcmp(addr->domain, sx->first_addr->domain) != 0 /* dom diff from first */
3532 DEBUG(D_transport) debug_printf("skipping different domain %s\n", addr->domain);
3534 /* Ensure the smtp-response reaper does not think the address had a RCPT
3535 command sent for it. Reset to PENDING_DEFER in smtp_deliver(), where we
3536 goto SEND_MESSAGE. */
3538 addr->transport_return = SKIP;
3539 if (!restart_addr) restart_addr = addr; /* note restart point */
3540 continue; /* skip this one */
3544 addr->dsn_aware = sx->peer_offered & OPTION_DSN
3545 ? dsn_support_yes : dsn_support_no;
3548 if (pipe_limit-- <= 0)
3549 { no_flush = FALSE; pipe_limit = 100; }
3551 no_flush = pipelining_active && !sx->verify
3552 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
3554 build_rcptcmd_options(sx, addr);
3556 /* Now send the RCPT command, and process outstanding responses when
3557 necessary. After a timeout on RCPT, we just end the function, leaving the
3558 yield as OK, because this error can often mean that there is a problem with
3559 just one address, so we don't want to delay the host. */
3561 rcpt_addr = transport_rcpt_address(addr, sx->conn_args.tblock->rcpt_include_affixes);
3564 if ( testflag(sx->addrlist, af_utf8_downcvt)
3565 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
3568 /*XXX could we use a per-address errstr here? Not fail the whole send? */
3569 errno = ERRNO_EXPANDFAIL;
3570 return -5; /*XXX too harsh? */
3574 cmds_sent = smtp_write_command(sx, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
3575 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
3577 if (cmds_sent < 0) return -5;
3580 switch(sync_responses(sx, cmds_sent, 0))
3582 case RESP_HAD_2_AND_5: sx->ok = TRUE; /* OK & progress made */
3583 case RESP_BIT_HAD_5XX: sx->completed_addr = TRUE; /* progress made */
3586 case RESP_BIT_HAD_2XX: sx->ok = TRUE; /* OK, but if LMTP, */
3587 if (!sx->lmtp) /* can't tell about progress yet */
3588 sx->completed_addr = TRUE;
3589 case RESP_NOERROR: /* No 2xx or 5xx, but no probs */
3590 /* If any RCPT got a 452 response then next_addr has been updated
3591 for restarting with a new MAIL on the same connection. Send no more
3592 RCPTs for this MAIL. */
3596 DEBUG(D_transport) debug_printf("seen 452 too-many-rcpts\n");
3597 sx->RCPT_452 = FALSE;
3598 /* sx->next_addr has been reset for fast_retry */
3603 case RESP_RCPT_TIMEO: return -3; /* Timeout on RCPT */
3604 case RESP_RCPT_ERROR: return -2; /* non-MAIL read i/o error */
3605 default: return -1; /* any MAIL error */
3607 #ifndef DISABLE_PIPE_CONNECT
3608 case RESP_EPIPE_EHLO_ERR: return -1; /* non-2xx for pipelined banner or EHLO */
3609 case RESP_EHLO_ERR_TLS: return -1; /* TLS first-read error */
3613 } /* Loop for next address */
3615 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3616 sx->next_addr = restart_addr ? restart_addr : addr;
3618 sx->next_addr = addr;
3625 /*****************************************************
3626 * Proxy TLS connection for another transport process *
3627 ******************************************************/
3629 Close the unused end of the pipe, fork once more, then use the given buffer
3630 as a staging area, and select on both the given fd and the TLS'd client-fd for
3631 data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
3632 Do blocking full-size writes, and reads under a timeout. Once both input
3633 channels are closed, exit the process.
3637 buf space to use for buffering
3638 bufsiz size of buffer
3639 pfd pipe filedescriptor array; [0] is comms to proxied process
3640 timeout per-read timeout, seconds
3641 host hostname of remote
3647 smtp_proxy_tls(void * ct_ctx, uschar * buf, size_t bsize, int * pfd,
3648 int timeout, const uschar * host)
3650 struct pollfd p[2] = {{.fd = tls_out.active.sock, .events = POLLIN},
3651 {.fd = pfd[0], .events = POLLIN}};
3653 BOOL send_tls_shutdown = TRUE;
3656 if ((rc = exim_fork(US"tls-proxy")))
3657 _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
3659 set_process_info("proxying TLS connection for continued transport to %s\n", host);
3663 time_t time_left = timeout;
3664 time_t time_start = time(NULL);
3669 rc = poll(p, 2, time_left * 1000);
3671 if (rc < 0 && errno == EINTR)
3672 if ((time_left -= time(NULL) - time_start) > 0) continue;
3676 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
3680 /* For errors where not readable, bomb out */
3682 if (p[0].revents & POLLERR || p[1].revents & POLLERR)
3684 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
3685 p[0].revents & POLLERR ? "tls" : "proxy");
3686 if (!(p[0].revents & POLLIN || p[1].events & POLLIN))
3688 DEBUG(D_transport) debug_printf("- but also readable; no exit yet\n");
3691 while (rc < 0 || !(p[0].revents & POLLIN || p[1].revents & POLLIN));
3693 /* handle inbound data */
3694 if (p[0].revents & POLLIN)
3695 if ((rc = tls_read(ct_ctx, buf, bsize)) <= 0) /* Expect -1 for EOF; */
3696 { /* that reaps the TLS Close Notify record */
3698 shutdown(pfd[0], SHUT_WR);
3702 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3703 if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
3705 /* Handle outbound data. We cannot combine payload and the TLS-close
3706 due to the limitations of the (pipe) channel feeding us. Maybe use a unix-domain
3708 if (p[1].revents & POLLIN)
3709 if ((rc = read(pfd[0], buf, bsize)) <= 0)
3713 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
3714 (void) setsockopt(tls_out.active.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
3716 tls_shutdown_wr(ct_ctx);
3717 send_tls_shutdown = FALSE;
3718 shutdown(tls_out.active.sock, SHUT_WR);
3721 for (int nbytes = 0; rc - nbytes > 0; nbytes += i)
3722 if ((i = tls_write(ct_ctx, buf + nbytes, rc - nbytes, FALSE)) < 0)
3725 while (p[0].fd >= 0 || p[1].fd >= 0);
3728 if (send_tls_shutdown) tls_close(ct_ctx, TLS_SHUTDOWN_NOWAIT);
3730 testharness_pause_ms(100); /* let logging complete */
3731 exim_exit(EXIT_SUCCESS);
3736 /*************************************************
3737 * Deliver address list to given host *
3738 *************************************************/
3740 /* If continue_hostname is not null, we get here only when continuing to
3741 deliver down an existing channel. The channel was passed as the standard
3742 input. TLS is never active on a passed channel; the previous process either
3743 closes it down before passing the connection on, or inserts a TLS-proxy
3744 process and passes on a cleartext conection.
3746 Otherwise, we have to make a connection to the remote host, and do the
3747 initial protocol exchange.
3749 When running as an MUA wrapper, if the sender or any recipient is rejected,
3750 temporarily or permanently, we force failure for all recipients.
3753 addrlist chain of potential addresses to deliver; only those whose
3754 transport_return field is set to PENDING_DEFER are currently
3755 being processed; others should be skipped - they have either
3756 been delivered to an earlier host or IP address, or been
3757 failed by one of them.
3758 host host to deliver to
3759 host_af AF_INET or AF_INET6
3760 defport default TCP/IP port to use if host does not specify, in host
3762 interface interface to bind to, or NULL
3763 tblock transport instance block
3764 message_defer set TRUE if yield is OK, but all addresses were deferred
3765 because of a non-recipient, non-host failure, that is, a
3766 4xx response to MAIL FROM, DATA, or ".". This is a defer
3767 that is specific to the message.
3768 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
3769 a second attempt after TLS initialization fails
3771 Returns: OK - the connection was made and the delivery attempted;
3772 the result for each address is in its data block.
3773 DEFER - the connection could not be made, or something failed
3774 while setting up the SMTP session, or there was a
3775 non-message-specific error, such as a timeout.
3776 ERROR - a filter command is specified for this transport,
3777 and there was a problem setting it up; OR helo_data
3778 or add_headers or authenticated_sender is specified
3779 for this transport, and the string failed to expand
3781 For all non-OK returns the first addr of the list carries the
3782 time taken for the attempt.
3786 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
3787 uschar *interface, transport_instance *tblock,
3788 BOOL *message_defer, BOOL suppress_tls)
3790 smtp_transport_options_block * ob = SOB tblock->options_block;
3795 uschar *message = NULL;
3796 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
3797 smtp_context * sx = store_get(sizeof(*sx), GET_TAINTED); /* tainted, for the data buffers */
3798 BOOL pass_message = FALSE;
3799 #ifdef EXPERIMENTAL_ESMTP_LIMITS
3800 BOOL mail_limit = FALSE;
3805 BOOL tcw_done = FALSE, tcw = FALSE;
3807 *message_defer = FALSE;
3809 memset(sx, 0, sizeof(*sx));
3810 sx->addrlist = addrlist;
3811 sx->conn_args.host = host;
3812 sx->conn_args.host_af = host_af;
3814 sx->conn_args.interface = interface;
3815 sx->helo_data = NULL;
3816 sx->conn_args.tblock = tblock;
3817 sx->conn_args.sock = -1;
3818 gettimeofday(&sx->delivery_start, NULL);
3819 sx->sync_addr = sx->first_addr = addrlist;
3826 /* Get the channel set up ready for a message, MAIL FROM being the next
3827 SMTP command to send. */
3829 if ((rc = smtp_setup_conn(sx, suppress_tls)) != OK)
3831 timesince(&addrlist->delivery_time, &sx->delivery_start);
3837 /* If the connection used DANE, ignore for now any addresses with incompatible
3838 domains. The SNI has to be the domain. Arrange a whole new TCP conn later,
3839 just in case only TLS isn't enough. */
3841 if (sx->conn_args.dane)
3843 const uschar * dane_domain = sx->first_addr->domain;
3845 for (address_item * a = sx->first_addr->next; a; a = a->next)
3846 if ( a->transport_return == PENDING_DEFER
3847 && Ustrcmp(dane_domain, a->domain) != 0)
3849 DEBUG(D_transport) debug_printf("DANE: holding %s for later\n", a->domain);
3851 a->transport_return = DANE;
3856 /* If there is a filter command specified for this transport, we can now
3857 set it up. This cannot be done until the identity of the host is known. */
3859 if (tblock->filter_command)
3861 transport_filter_timeout = tblock->filter_timeout;
3863 /* On failure, copy the error to all addresses, abandon the SMTP call, and
3866 if (!transport_set_up_command(&transport_filter_argv,
3867 tblock->filter_command, TSUC_EXPAND_ARGS, DEFER, addrlist,
3868 string_sprintf("%.50s transport filter", tblock->name), NULL))
3870 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
3871 FALSE, &sx->delivery_start);
3876 if ( transport_filter_argv
3877 && *transport_filter_argv
3878 && **transport_filter_argv
3879 && smtp_peer_options & OPTION_CHUNKING
3880 #ifndef DISABLE_DKIM
3881 /* When dkim signing, chunking is handled even with a transport-filter */
3882 && !(ob->dkim.dkim_private_key && ob->dkim.dkim_domain && ob->dkim.dkim_selector)
3883 && !ob->dkim.force_bodyhash
3887 smtp_peer_options &= ~OPTION_CHUNKING;
3888 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
3892 /* For messages that have more than the maximum number of envelope recipients,
3893 we want to send several transactions down the same SMTP connection. (See
3894 comments in deliver.c as to how this reconciles, heuristically, with
3895 remote_max_parallel.) This optimization was added to Exim after the following
3896 code was already working. The simplest way to put it in without disturbing the
3897 code was to use a goto to jump back to this point when there is another
3898 transaction to handle. */
3901 sx->from_addr = return_path;
3902 sx->sync_addr = sx->first_addr;
3904 sx->send_rset = TRUE;
3905 sx->completed_addr = FALSE;
3908 /* If we are a continued-connection-after-verify the MAIL and RCPT
3909 commands were already sent; do not re-send but do mark the addrs as
3910 having been accepted up to RCPT stage. A traditional cont-conn
3911 always has a sequence number greater than one. */
3913 if (continue_hostname && continue_sequence == 1)
3915 /* sx->pending_MAIL = FALSE; */
3917 /* sx->next_addr = NULL; */
3919 for (address_item * addr = addrlist; addr; addr = addr->next)
3920 addr->transport_return = PENDING_OK;
3924 /* Initiate a message transfer. */
3926 switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))
3929 case -1: case -2: goto RESPONSE_FAILED;
3930 case -3: goto END_OFF;
3931 case -4: goto SEND_QUIT;
3932 default: goto SEND_FAILED;
3935 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
3936 permanently or temporarily. We should have flushed and synced after the last
3944 for (a = sx->first_addr, cnt = 0; a && cnt < sx->max_rcpt; a = a->next, cnt++)
3945 if (a->transport_return != PENDING_OK)
3947 /*XXX could we find a better errno than 0 here? */
3948 set_errno_nohost(addrlist, 0, a->message, FAIL,
3949 testflag(a, af_pass_message), &sx->delivery_start);
3956 /* If ok is TRUE, we know we have got at least one good recipient, and must now
3957 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
3958 have a good recipient buffered up if we are pipelining. We don't want to waste
3959 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
3960 are pipelining. The responses are all handled by sync_responses().
3961 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
3964 if ( !(smtp_peer_options & OPTION_CHUNKING)
3965 && (sx->ok || (pipelining_active && !mua_wrapper)))
3967 int count = smtp_write_command(sx, SCMD_FLUSH, "DATA\r\n");
3969 if (count < 0) goto SEND_FAILED;
3971 switch(sync_responses(sx, count, sx->ok ? +1 : -1))
3973 case RESP_HAD_2_AND_5: sx->ok = TRUE; /* OK & progress made */
3974 case RESP_BIT_HAD_5XX: sx->completed_addr = TRUE; /* progress made */
3977 case RESP_BIT_HAD_2XX: sx->ok = TRUE; /* OK, but if LMTP, */
3978 if (!sx->lmtp) /* can't tell about progress yet */
3979 sx->completed_addr = TRUE;
3980 case RESP_NOERROR: break; /* No 2xx or 5xx, but no probs */
3982 case RESP_RCPT_TIMEO: goto END_OFF;
3984 #ifndef DISABLE_PIPE_CONNECT
3985 case -5: /* TLS first-read error */
3986 case -4: HDEBUG(D_transport)
3987 debug_printf("failed reaping pipelined cmd responses\n");
3989 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
3991 pipelining_active = FALSE;
3992 data_command = string_copy(big_buffer); /* Save for later error message */
3995 /* If there were no good recipients (but otherwise there have been no
3996 problems), just set ok TRUE, since we have handled address-specific errors
3997 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
3998 for handling the SMTP dot-handling protocol, flagging to apply to headers as
3999 well as body. Set the appropriate timeout value to be used for each chunk.
4000 (Haven't been able to make it work using select() for writing yet.) */
4003 && (!(smtp_peer_options & OPTION_CHUNKING) || !pipelining_active))
4005 /* Save the first address of the next batch. */
4006 sx->first_addr = sx->next_addr;
4012 transport_ctx tctx = {
4013 .u = {.fd = sx->cctx.sock}, /*XXX will this need TLS info? */
4016 .check_string = US".",
4017 .escape_string = US"..", /* Escaping strings */
4019 topt_use_crlf | topt_escape_headers
4020 | (tblock->body_only ? topt_no_headers : 0)
4021 | (tblock->headers_only ? topt_no_body : 0)
4022 | (tblock->return_path_add ? topt_add_return_path : 0)
4023 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
4024 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
4027 /* If using CHUNKING we need a callback from the generic transport
4028 support to us, for the sending of BDAT smtp commands and the reaping
4029 of responses. The callback needs a whole bunch of state so set up
4030 a transport-context structure to be passed around. */
4032 if (smtp_peer_options & OPTION_CHUNKING)
4034 tctx.check_string = tctx.escape_string = NULL;
4035 tctx.options |= topt_use_bdat;
4036 tctx.chunk_cb = smtp_chunk_cmd_callback;
4037 sx->pending_BDAT = FALSE;
4038 sx->good_RCPT = sx->ok;
4040 tctx.smtp_context = sx;
4043 tctx.options |= topt_end_dot;
4045 /* Save the first address of the next batch. */
4046 sx->first_addr = sx->next_addr;
4048 /* Responses from CHUNKING commands go in buffer. Otherwise,
4049 there has not been a response. */
4053 sigalrm_seen = FALSE;
4054 transport_write_timeout = ob->data_timeout;
4055 smtp_command = US"sending data block"; /* For error messages */
4056 DEBUG(D_transport|D_v)
4057 if (smtp_peer_options & OPTION_CHUNKING)
4058 debug_printf(" will write message using CHUNKING\n");
4060 debug_printf(" SMTP>> (writing message)\n");
4061 transport_count = 0;
4063 #ifndef DISABLE_DKIM
4065 # ifdef MEASURE_TIMING
4067 gettimeofday(&t0, NULL);
4069 dkim_exim_sign_init();
4070 # ifdef EXPERIMENTAL_ARC
4072 uschar * s = ob->arc_sign;
4075 if (!(ob->dkim.arc_signspec = s = expand_string(s)))
4077 if (!f.expand_string_forcedfail)
4079 message = US"failed to expand arc_sign";
4086 /* Ask dkim code to hash the body for ARC */
4087 (void) arc_ams_setup_sign_bodyhash();
4088 ob->dkim.force_bodyhash = TRUE;
4093 # ifdef MEASURE_TIMING
4094 report_time_since(&t0, US"dkim_exim_sign_init (delta)");
4099 /* See if we can pipeline QUIT. Reasons not to are
4100 - pipelining not active
4101 - not ok to send quit
4102 - errors in amtp transation responses
4103 - more addrs to send for this message or this host
4104 - this message was being retried
4105 - more messages for this host
4106 If we can, we want the message-write to not flush (the tail end of) its data out. */
4108 if ( sx->pipelining_used
4109 && (sx->ok && sx->completed_addr || smtp_peer_options & OPTION_CHUNKING)
4111 && !(sx->first_addr || f.continue_more)
4112 && f.deliver_firsttime
4115 smtp_compare_t t_compare =
4116 {.tblock = tblock, .current_sender_address = sender_address};
4121 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4122 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4126 transport_check_waiting(tblock->name, host->name,
4127 tblock->connection_max_messages, new_message_id,
4128 (oicf)smtp_are_same_identities, (void*)&t_compare);
4131 HDEBUG(D_transport) debug_printf("will pipeline QUIT\n");
4132 tctx.options |= topt_no_flush;
4136 #ifndef DISABLE_DKIM
4137 sx->ok = dkim_transport_write_message(&tctx, &ob->dkim, CUSS &message);
4139 sx->ok = transport_write_message(&tctx, 0);
4142 /* transport_write_message() uses write() because it is called from other
4143 places to write to non-sockets. This means that under some OS (e.g. Solaris)
4144 it can exit with "Broken pipe" as its error. This really means that the
4145 socket got closed at the far end. */
4147 transport_write_timeout = 0; /* for subsequent transports */
4149 /* Failure can either be some kind of I/O disaster (including timeout),
4150 or the failure of a transport filter or the expansion of added headers.
4151 Or, when CHUNKING, it can be a protocol-detected failure. */
4154 if (message) goto SEND_FAILED;
4155 else goto RESPONSE_FAILED;
4157 /* We used to send the terminating "." explicitly here, but because of
4158 buffering effects at both ends of TCP/IP connections, you don't gain
4159 anything by keeping it separate, so it might as well go in the final
4160 data buffer for efficiency. This is now done by setting the topt_end_dot
4163 smtp_command = US"end of data";
4165 /* If we can pipeline a QUIT with the data them send it now. If a new message
4166 for this host appeared in the queue while data was being sent, we will not see
4167 it and it will have to wait for a queue run. If there was one but another
4168 thread took it, we might attempt to send it - but locking of spoolfiles will
4169 detect that. Use _MORE to get QUIT in FIN segment. */
4171 if (tcw_done && !tcw)
4173 /*XXX jgh 2021/03/10 google et. al screwup. G, at least, sends TCP FIN in response to TLS
4174 close-notify. Under TLS 1.3, violating RFC.
4175 However, TLS 1.2 does not have half-close semantics. */
4177 if ( sx->cctx.tls_ctx
4178 #if 0 && !defined(DISABLE_TLS)
4179 && Ustrcmp(tls_out.ver, "TLS1.3") != 0
4181 || !f.deliver_firsttime
4183 { /* Send QUIT now and not later */
4184 (void)smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n");
4185 sx->send_quit = FALSE;
4188 { /* add QUIT to the output buffer */
4189 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4190 sx->send_quit = FALSE; /* avoid sending it later */
4193 if (sx->cctx.tls_ctx && sx->send_tlsclose) /* need to send TLS Close Notify */
4195 # ifdef EXIM_TCP_CORK /* Use _CORK to get Close Notify in FIN segment */
4196 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4198 tls_shutdown_wr(sx->cctx.tls_ctx);
4199 sx->send_tlsclose = FALSE; /* avoid later repeat */
4202 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4203 shutdown(sx->cctx.sock, SHUT_WR); /* flush output buffer, with TCP FIN */
4207 if (smtp_peer_options & OPTION_CHUNKING && sx->cmd_count > 1)
4209 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
4210 switch(sync_responses(sx, sx->cmd_count-1, 0))
4212 case RESP_HAD_2_AND_5: sx->ok = TRUE; /* OK & progress made */
4213 case RESP_BIT_HAD_5XX: sx->completed_addr = TRUE; /* progress made */
4216 case RESP_BIT_HAD_2XX: sx->ok = TRUE; /* OK, but if LMTP, */
4217 if (!sx->lmtp) /* can't tell about progress yet */
4218 sx->completed_addr = TRUE;
4219 case RESP_NOERROR: break; /* No 2xx or 5xx, but no probs */
4221 case RESP_RCPT_TIMEO: goto END_OFF; /* Timeout on RCPT */
4223 #ifndef DISABLE_PIPE_CONNECT
4224 case RESP_EHLO_ERR_TLS: /* TLS first-read error */
4225 case RESP_EPIPE_EHLO_ERR: HDEBUG(D_transport)
4226 debug_printf("failed reaping pipelined cmd responses\n");
4228 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
4232 #ifndef DISABLE_PRDR
4233 /* For PRDR we optionally get a partial-responses warning followed by the
4234 individual responses, before going on with the overall response. If we don't
4235 get the warning then deal with per non-PRDR. */
4239 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '3', ob->final_timeout);
4240 if (!sx->ok && errno == 0) switch(sx->buffer[0])
4242 case '2': sx->prdr_active = FALSE;
4245 case '4': errno = ERRNO_DATA4XX;
4246 addrlist->more_errno |=
4247 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4254 /* For non-PRDR SMTP, we now read a single response that applies to the
4255 whole message. If it is OK, then all the addresses have been delivered. */
4259 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4261 if (!sx->ok && errno == 0 && sx->buffer[0] == '4')
4263 errno = ERRNO_DATA4XX;
4264 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4268 /* For LMTP, we get back a response for every RCPT command that we sent;
4269 some may be accepted and some rejected. For those that get a response, their
4270 status is fixed; any that are accepted have been handed over, even if later
4271 responses crash - at least, that's how I read RFC 2033.
4273 If all went well, mark the recipient addresses as completed, record which
4274 host/IPaddress they were delivered to, and cut out RSET when sending another
4275 message down the same channel. Write the completed addresses to the journal
4276 now so that they are recorded in case there is a crash of hardware or
4277 software before the spool gets updated. Also record the final SMTP
4278 confirmation if needed (for SMTP only). */
4283 struct timeval delivery_time;
4285 uschar * conf = NULL;
4287 timesince(&delivery_time, &sx->delivery_start);
4288 sx->send_rset = FALSE;
4289 pipelining_active = FALSE;
4291 /* Set up confirmation if needed - applies only to SMTP */
4294 #ifdef DISABLE_EVENT
4295 LOGGING(smtp_confirmation) &&
4300 const uschar * s = string_printing(sx->buffer);
4301 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4302 conf = s == sx->buffer ? US string_copy(s) : US s;
4305 /* Process all transported addresses - for LMTP or PRDR, read a status for
4306 each one. We used to drop out at first_addr, until someone returned a 452
4307 followed by a 250... and we screwed up the accepted addresses. */
4309 for (address_item * addr = addrlist; addr; addr = addr->next)
4311 if (addr->transport_return != PENDING_OK) continue;
4313 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
4314 remaining addresses. Otherwise, it's a return code for just the one
4315 address. For temporary errors, add a retry item for the address so that
4316 it doesn't get tried again too soon. */
4318 #ifndef DISABLE_PRDR
4319 if (sx->lmtp || sx->prdr_active)
4324 if (!smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4327 if (errno != 0 || sx->buffer[0] == 0) goto RESPONSE_FAILED;
4328 addr->message = string_sprintf(
4329 #ifndef DISABLE_PRDR
4330 "%s error after %s: %s", sx->prdr_active ? "PRDR":"LMTP",
4332 "LMTP error after %s: %s",
4334 data_command, string_printing(sx->buffer));
4335 setflag(addr, af_pass_message); /* Allow message to go to user */
4336 if (sx->buffer[0] == '5')
4337 addr->transport_return = FAIL;
4340 errno = ERRNO_DATA4XX;
4341 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4342 addr->transport_return = DEFER;
4343 #ifndef DISABLE_PRDR
4344 if (!sx->prdr_active)
4346 retry_add_item(addr, addr->address_retry_key, 0);
4350 sx->completed_addr = TRUE; /* NOW we can set this flag */
4351 if (LOGGING(smtp_confirmation))
4353 const uschar *s = string_printing(sx->buffer);
4354 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
4355 conf = (s == sx->buffer) ? US string_copy(s) : US s;
4359 /* SMTP, or success return from LMTP for this address. Pass back the
4360 actual host that was used. */
4362 addr->transport_return = OK;
4363 addr->host_used = host;
4364 addr->delivery_time = delivery_time;
4365 addr->special_action = flag;
4366 addr->message = conf;
4368 if (tcp_out_fastopen)
4370 setflag(addr, af_tcp_fastopen_conn);
4371 if (tcp_out_fastopen >= TFO_USED_NODATA) setflag(addr, af_tcp_fastopen);
4372 if (tcp_out_fastopen >= TFO_USED_DATA) setflag(addr, af_tcp_fastopen_data);
4374 if (sx->pipelining_used) setflag(addr, af_pipelining);
4375 #ifndef DISABLE_PIPE_CONNECT
4376 if (sx->early_pipe_active) setflag(addr, af_early_pipe);
4378 #ifndef DISABLE_PRDR
4379 if (sx->prdr_active) setflag(addr, af_prdr_used);
4381 if (smtp_peer_options & OPTION_CHUNKING) setflag(addr, af_chunking_used);
4384 #ifndef DISABLE_PRDR
4385 if (!sx->prdr_active)
4388 /* Update the journal. For homonymic addresses, use the base address plus
4389 the transport name. See lots of comments in deliver.c about the reasons
4390 for the complications when homonyms are involved. Just carry on after
4391 write error, as it may prove possible to update the spool file later. */
4393 if (testflag(addr, af_homonym))
4394 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4396 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4398 DEBUG(D_deliver) debug_printf("S:journalling %s", sx->buffer);
4399 len = Ustrlen(CS sx->buffer);
4400 if (write(journal_fd, sx->buffer, len) != len)
4401 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4402 "%s: %s", sx->buffer, strerror(errno));
4406 #ifndef DISABLE_PRDR
4407 if (sx->prdr_active)
4409 const uschar * overall_message;
4411 /* PRDR - get the final, overall response. For any non-success
4412 upgrade all the address statuses. */
4414 sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2',
4418 if(errno == 0 && sx->buffer[0] == '4')
4420 errno = ERRNO_DATA4XX;
4421 addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
4423 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4424 if (sx->buffer[0] == '5' || addr->transport_return == OK)
4425 addr->transport_return = PENDING_OK; /* allow set_errno action */
4426 goto RESPONSE_FAILED;
4429 /* Append the overall response to the individual PRDR response for logging
4430 and update the journal, or setup retry. */
4432 overall_message = string_printing(sx->buffer);
4433 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4434 if (addr->transport_return == OK)
4435 addr->message = string_sprintf("%s\\n%s", addr->message, overall_message);
4437 for (address_item * addr = addrlist; addr != sx->first_addr; addr = addr->next)
4438 if (addr->transport_return == OK)
4440 if (testflag(addr, af_homonym))
4441 sprintf(CS sx->buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
4443 sprintf(CS sx->buffer, "%.500s\n", addr->unique);
4445 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx->buffer);
4446 len = Ustrlen(CS sx->buffer);
4447 if (write(journal_fd, sx->buffer, len) != len)
4448 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
4449 "%s: %s", sx->buffer, strerror(errno));
4451 else if (addr->transport_return == DEFER)
4452 /*XXX magic value -2 ? maybe host+message ? */
4453 retry_add_item(addr, addr->address_retry_key, -2);
4457 /* Ensure the journal file is pushed out to disk. */
4459 if (EXIMfsync(journal_fd) < 0)
4460 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
4466 /* Handle general (not specific to one address) failures here. The value of ok
4467 is used to skip over this code on the falling through case. A timeout causes a
4468 deferral. Other errors may defer or fail according to the response code, and
4469 may set up a special errno value, e.g. after connection chopped, which is
4470 assumed if errno == 0 and there is no text in the buffer. If control reaches
4471 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
4472 the problem is not related to this specific message. */
4477 uschar * set_message;
4483 /* Clear send_quit flag if needed. Do not set. */
4484 sx->send_quit &= check_response(host, &save_errno, addrlist->more_errno,
4485 sx->buffer, &code, &message, &pass_message);
4493 message = string_sprintf("smtp send to %s [%s] failed: %s",
4494 host->name, host->address, message ? message : US strerror(save_errno));
4495 sx->send_quit = FALSE;
4503 sx->ok = FALSE; /* For when reached by GOTO */
4504 set_message = message;
4506 /* We want to handle timeouts after MAIL or "." and loss of connection after
4507 "." specially. They can indicate a problem with the sender address or with
4508 the contents of the message rather than a real error on the connection. These
4509 cases are treated in the same way as a 4xx response. This next bit of code
4510 does the classification. */
4517 message_error = TRUE;
4521 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
4522 Ustrncmp(smtp_command,"end ",4) == 0;
4525 case ERRNO_SMTPCLOSED:
4526 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
4529 #ifndef DISABLE_DKIM
4531 /* DKIM signing failure: avoid thinking we pipelined quit,
4532 just abandon the message and close the socket. */
4534 message_error = FALSE;
4535 # ifndef DISABLE_TLS
4536 if (sx->cctx.tls_ctx)
4538 tls_close(sx->cctx.tls_ctx,
4539 sx->send_tlsclose ? TLS_SHUTDOWN_WAIT : TLS_SHUTDOWN_WONLY);
4540 sx->cctx.tls_ctx = NULL;
4546 message_error = FALSE;
4550 /* Handle the cases that are treated as message errors. These are:
4552 (a) negative response or timeout after MAIL
4553 (b) negative response after DATA
4554 (c) negative response or timeout or dropped connection after "."
4555 (d) utf8 support required and not offered
4557 It won't be a negative response or timeout after RCPT, as that is dealt
4558 with separately above. The action in all cases is to set an appropriate
4559 error code for all the addresses, but to leave yield set to OK because the
4560 host itself has not failed. Of course, it might in practice have failed
4561 when we've had a timeout, but if so, we'll discover that at the next
4562 delivery attempt. For a temporary error, set the message_defer flag, and
4563 write to the logs for information if this is not the last host. The error
4564 for the last host will be logged as part of the address's log line. */
4568 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
4570 /* If there's an errno, the message contains just the identity of
4575 else /* Anything other than 5 is treated as temporary */
4579 message = US string_sprintf("%s: %s", message, strerror(save_errno));
4581 write_logs(host, message, sx->first_addr ? sx->first_addr->basic_errno : 0);
4583 *message_defer = TRUE;
4586 DEBUG(D_transport) if (sx->cctx.sock >= 0)
4589 if (ioctl(sx->cctx.sock, TIOCOUTQ, &n) == 0)
4590 debug_printf("%d bytes remain in socket output buffer\n", n);
4594 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
4595 ".", or some other transportation error. We defer all addresses and yield
4596 DEFER, except for the case of failed add_headers expansion, or a transport
4597 filter failure, when the yield should be ERROR, to stop it trying other
4602 #ifndef DISABLE_PIPE_CONNECT
4603 /* If we were early-pipelinng and the actual EHLO response did not match
4604 the cached value we assumed, we could have detected it and passed a
4605 custom errno through to here. It would be nice to RSET and retry right
4606 away, but to reliably do that we eould need an extra synch point before
4607 we committed to data and that would discard half the gained roundrips.
4608 Or we could summarily drop the TCP connection. but that is also ugly.
4609 Instead, we ignore the possibility (having freshened the cache) and rely
4610 on the server telling us with a nonmessage error if we have tried to
4611 do something it no longer supports. */
4614 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
4615 save_errno == ERRNO_FILTER_FAIL) ? ERROR : DEFER;
4619 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host,
4620 #ifdef EXPERIMENTAL_DSN_INFO
4621 sx->smtp_greeting, sx->helo_response,
4623 &sx->delivery_start);
4626 /* If all has gone well, send_quit will be set TRUE, implying we can end the
4627 SMTP session tidily. However, if there were too many addresses to send in one
4628 message (indicated by first_addr being non-NULL) we want to carry on with the
4629 rest of them. Also, it is desirable to send more than one message down the SMTP
4630 connection if there are several waiting, provided we haven't already sent so
4631 many as to hit the configured limit. The function transport_check_waiting looks
4632 for a waiting message and returns its id. Then transport_pass_socket tries to
4633 set up a continued delivery by passing the socket on to another process. The
4634 variable send_rset is FALSE if a message has just been successfully transferred.
4636 If we are already sending down a continued channel, there may be further
4637 addresses not yet delivered that are aimed at the same host, but which have not
4638 been passed in this run of the transport. In this case, continue_more will be
4639 true, and all we should do is send RSET if necessary, and return, leaving the
4642 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
4643 do not want to continue with other messages down the same channel, because that
4644 can lead to looping between two or more messages, all with the same,
4645 temporarily failing address(es). [The retry information isn't updated yet, so
4646 new processes keep on trying.] We probably also don't want to try more of this
4647 message's addresses either.
4649 If we have started a TLS session, we have to end it before passing the
4650 connection to a new process. However, not all servers can handle this (Exim
4651 can), so we do not pass such a connection on if the host matches
4652 hosts_nopass_tls. */
4655 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
4656 "yield=%d first_address is %sNULL\n", sx->ok, sx->send_quit,
4657 sx->send_rset, f.continue_more, yield, sx->first_addr ? "not " : "");
4659 if (sx->completed_addr && sx->ok && sx->send_quit)
4660 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4661 if (mail_limit = continue_sequence >= sx->max_mail)
4664 debug_printf("reached limit %u for MAILs per conn\n", sx->max_mail);
4669 smtp_compare_t t_compare =
4670 {.tblock = tblock, .current_sender_address = sender_address};
4672 if ( sx->first_addr /* more addrs for this message */
4673 || f.continue_more /* more addrs for continued-host */
4674 || tcw_done && tcw /* more messages for host */
4677 ( tls_out.active.sock < 0 && !continue_proxy_cipher
4678 || verify_check_given_host(CUSS &ob->hosts_nopass_tls, host) != OK
4682 transport_check_waiting(tblock->name, host->name,
4683 sx->max_mail, new_message_id,
4684 (oicf)smtp_are_same_identities, (void*)&t_compare)
4691 if (! (sx->ok = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0))
4693 msg = US string_sprintf("smtp send to %s [%s] failed: %s", host->name,
4694 host->address, strerror(errno));
4695 sx->send_quit = FALSE;
4697 else if (! (sx->ok = smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4698 '2', ob->command_timeout)))
4701 sx->send_quit = check_response(host, &errno, 0, sx->buffer, &code, &msg,
4705 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
4706 host->name, host->address, msg);
4710 /* Either RSET was not needed, or it succeeded */
4717 int socket_fd = sx->cctx.sock;
4719 if (sx->first_addr) /* More addresses still to be sent */
4720 { /* for this message */
4721 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4722 /* Any that we marked as skipped, reset to do now */
4723 for (address_item * a = sx->first_addr; a; a = a->next)
4724 if (a->transport_return == SKIP)
4725 a->transport_return = PENDING_DEFER;
4727 continue_sequence++; /* for consistency */
4728 clearflag(sx->first_addr, af_new_conn);
4729 setflag(sx->first_addr, af_cont_conn); /* Causes * in logging */
4730 pipelining_active = sx->pipelining_used; /* was cleared at DATA */
4734 /* Unless caller said it already has more messages listed for this host,
4735 pass the connection on to a new Exim process (below, the call to
4736 transport_pass_socket). If the caller has more ready, just return with
4737 the connection still open. */
4740 if (tls_out.active.sock >= 0)
4741 if ( f.continue_more
4742 || verify_check_given_host(CUSS &ob->hosts_noproxy_tls, host) == OK)
4744 /* Before passing the socket on, or returning to caller with it still
4745 open, we must shut down TLS. Not all MTAs allow for the continuation
4746 of the SMTP session when TLS is shut down. We test for this by sending
4747 a new EHLO. If we don't get a good response, we don't attempt to pass
4749 NB: TLS close is *required* per RFC 9266 when tls-exporter info has
4750 been used, which we do under TLSv1.3 for the gsasl SCRAM*PLUS methods.
4751 But we were always doing it anyway. */
4753 tls_close(sx->cctx.tls_ctx,
4754 sx->send_tlsclose ? TLS_SHUTDOWN_WAIT : TLS_SHUTDOWN_WONLY);
4755 sx->send_tlsclose = FALSE;
4756 sx->cctx.tls_ctx = NULL;
4757 tls_out.active.sock = -1;
4758 smtp_peer_options = smtp_peer_options_wrap;
4760 && smtp_write_command(sx, SCMD_FLUSH, "EHLO %s\r\n", sx->helo_data)
4762 && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer),
4763 '2', ob->command_timeout);
4765 if (sx->ok && f.continue_more)
4766 goto TIDYUP; /* More addresses for another run */
4770 /* Set up a pipe for proxying TLS for the new transport process */
4772 smtp_peer_options |= OPTION_TLS;
4773 if ((sx->ok = socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
4776 set_errno(sx->first_addr, errno, US"internal allocation problem",
4778 # ifdef EXPERIMENTAL_DSN_INFO
4779 sx->smtp_greeting, sx->helo_response,
4781 &sx->delivery_start);
4785 if (f.continue_more)
4786 goto TIDYUP; /* More addresses for another run */
4788 /* If the socket is successfully passed, we mustn't send QUIT (or
4789 indeed anything!) from here. */
4791 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
4792 propagate it from the initial
4794 if (sx->ok && transport_pass_socket(tblock->name, host->name,
4795 host->address, new_message_id, socket_fd
4796 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4797 , sx->peer_limit_mail, sx->peer_limit_rcpt, sx->peer_limit_rcptdom
4801 sx->send_quit = FALSE;
4803 /* We have passed the client socket to a fresh transport process.
4804 If TLS is still active, we need to proxy it for the transport we
4805 just passed the baton to. Fork a child to to do it, and return to
4806 get logging done asap. Which way to place the work makes assumptions
4807 about post-fork prioritisation which may not hold on all platforms. */
4809 if (tls_out.active.sock >= 0)
4811 int pid = exim_fork(US"tls-proxy-interproc");
4812 if (pid == 0) /* child; fork again to disconnect totally */
4814 /* does not return */
4815 smtp_proxy_tls(sx->cctx.tls_ctx, sx->buffer, sizeof(sx->buffer), pfd,
4816 ob->command_timeout, host->name);
4819 if (pid > 0) /* parent */
4822 /* tidy the inter-proc to disconn the proxy proc */
4823 waitpid(pid, NULL, 0);
4824 tls_close(sx->cctx.tls_ctx, TLS_NO_SHUTDOWN);
4825 sx->cctx.tls_ctx = NULL;
4826 (void)close(sx->cctx.sock);
4828 continue_transport = NULL;
4829 continue_hostname = NULL;
4832 log_write(0, LOG_PANIC_DIE, "fork failed");
4838 /* If RSET failed and there are addresses left, they get deferred. */
4840 set_errno(sx->first_addr, errno, msg, DEFER, FALSE, host,
4841 #ifdef EXPERIMENTAL_DSN_INFO
4842 sx->smtp_greeting, sx->helo_response,
4844 &sx->delivery_start);
4848 /* End off tidily with QUIT unless the connection has died or the socket has
4849 been passed to another process. */
4853 { /* Use _MORE to get QUIT in FIN segment */
4854 (void)smtp_write_command(sx, SCMD_MORE, "QUIT\r\n");
4856 if (sx->cctx.tls_ctx && sx->send_tlsclose)
4858 # ifdef EXIM_TCP_CORK /* Use _CORK to get TLS Close Notify in FIN segment */
4859 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4861 tls_shutdown_wr(sx->cctx.tls_ctx);
4862 sx->send_tlsclose = FALSE;
4869 /* Close the socket, and return the appropriate value, first setting
4870 works because the NULL setting is passed back to the calling process, and
4871 remote_max_parallel is forced to 1 when delivering over an existing connection,
4873 If all went well and continue_more is set, we shouldn't actually get here if
4874 there are further addresses, as the return above will be taken. However,
4875 writing RSET might have failed, or there may be other addresses whose hosts are
4876 specified in the transports, and therefore not visible at top level, in which
4877 case continue_more won't get set. */
4881 /* This flushes data queued in the socket, being the QUIT and any TLS Close,
4882 sending them along with the client FIN flag. Us (we hope) sending FIN first
4883 means we (client) take the TIME_WAIT state, so the server (which likely has a
4884 higher connection rate) does not have to. */
4886 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(shutdown)>>\n");
4887 shutdown(sx->cctx.sock, SHUT_WR);
4890 if (sx->send_quit || tcw_done && !tcw)
4892 /* Wait for (we hope) ack of our QUIT, and a server FIN. Discard any data
4893 received, then discard the socket. Any packet received after then, or receive
4894 data still in the socket, will get a RST - hence the pause/drain. */
4896 /* Reap the response to QUIT, timing out after one second */
4897 (void) smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', 1);
4899 if (sx->cctx.tls_ctx)
4903 /* Reap the TLS Close Notify from the server, timing out after one second */
4904 sigalrm_seen = FALSE;
4907 n = tls_read(sx->cctx.tls_ctx, sx->inbuffer, sizeof(sx->inbuffer));
4908 while (!sigalrm_seen && n > 0);
4911 if (sx->send_tlsclose)
4913 # ifdef EXIM_TCP_CORK
4914 (void) setsockopt(sx->cctx.sock, IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
4916 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WAIT);
4919 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_WONLY);
4920 sx->cctx.tls_ctx = NULL;
4924 /* Drain any trailing data from the socket before close, to avoid sending a RST */
4926 if ( poll_one_fd(sx->cctx.sock, POLLIN, 20) != 0 /* 20ms */
4927 && fcntl(sx->cctx.sock, F_SETFL, O_NONBLOCK) == 0)
4928 for (int i = 16, n; /* drain socket */
4929 (n = read(sx->cctx.sock, sx->inbuffer, sizeof(sx->inbuffer))) > 0 && i > 0;
4930 i--) HDEBUG(D_transport|D_acl|D_v)
4933 debug_printf_indent(" SMTP(drain %d bytes)<< %.*s\n", n, m, sx->inbuffer);
4934 for (m = 0; m < n; m++)
4935 debug_printf("0x%02x\n", sx->inbuffer[m]);
4938 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
4939 (void)close(sx->cctx.sock);
4941 continue_transport = NULL;
4942 continue_hostname = NULL;
4943 smtp_debug_cmd_report();
4945 #ifndef DISABLE_EVENT
4946 (void) event_raise(tblock->event_action, US"tcp:close", NULL, NULL);
4952 sx->first_addr = NULL;
4953 for (address_item * a = sx->addrlist->next; a; a = a->next)
4954 if (a->transport_return == DANE)
4956 a->transport_return = PENDING_DEFER;
4957 if (!sx->first_addr)
4959 /* Remember the new start-point in the addrlist, for smtp_setup_conn()
4960 to get the domain string for SNI */
4963 clearflag(a, af_cont_conn);
4964 setflag(a, af_new_conn); /* clear * from logging */
4965 DEBUG(D_transport) debug_printf("DANE: go-around for %s\n", a->domain);
4968 continue_sequence = 1; /* for consistency */
4973 #ifdef EXPERIMENTAL_ESMTP_LIMITS
4974 if (mail_limit && sx->first_addr)
4976 /* Reset the sequence count since we closed the connection. This is flagged
4977 on the pipe back to the delivery process so that a non-continued-conn delivery
4980 continue_sequence = 1; /* for consistency */
4981 clearflag(sx->first_addr, af_cont_conn);
4982 setflag(sx->first_addr, af_new_conn); /* clear * from logging */
4991 if (dane_held) for (address_item * a = sx->addrlist->next; a; a = a->next)
4992 if (a->transport_return == DANE)
4993 a->transport_return = PENDING_DEFER;
5001 /*************************************************
5002 * Closedown entry point *
5003 *************************************************/
5005 /* This function is called when exim is passed an open smtp channel
5006 from another incarnation, but the message which it has been asked
5007 to deliver no longer exists. The channel is on stdin.
5009 We might do fancy things like looking for another message to send down
5010 the channel, but if the one we sought has gone, it has probably been
5011 delivered by some other process that itself will seek further messages,
5012 so just close down our connection.
5014 Argument: pointer to the transport instance block
5019 smtp_transport_closedown(transport_instance *tblock)
5021 smtp_transport_options_block * ob = SOB tblock->options_block;
5022 client_conn_ctx cctx;
5023 smtp_context sx = {0};
5025 uschar inbuffer[4096];
5026 uschar outbuffer[16];
5028 /*XXX really we need an active-smtp-client ctx, rather than assuming stdout */
5029 cctx.sock = fileno(stdin);
5030 cctx.tls_ctx = cctx.sock == tls_out.active.sock ? tls_out.active.tls_ctx : NULL;
5032 sx.inblock.cctx = &cctx;
5033 sx.inblock.buffer = inbuffer;
5034 sx.inblock.buffersize = sizeof(inbuffer);
5035 sx.inblock.ptr = inbuffer;
5036 sx.inblock.ptrend = inbuffer;
5038 sx.outblock.cctx = &cctx;
5039 sx.outblock.buffersize = sizeof(outbuffer);
5040 sx.outblock.buffer = outbuffer;
5041 sx.outblock.ptr = outbuffer;
5042 sx.outblock.cmd_count = 0;
5043 sx.outblock.authenticating = FALSE;
5045 (void)smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
5046 (void)smtp_read_response(&sx, buffer, sizeof(buffer), '2', ob->command_timeout);
5047 (void)close(cctx.sock);
5052 /*************************************************
5053 * Prepare addresses for delivery *
5054 *************************************************/
5056 /* This function is called to flush out error settings from previous delivery
5057 attempts to other hosts. It also records whether we got here via an MX record
5058 or not in the more_errno field of the address. We are interested only in
5059 addresses that are still marked DEFER - others may have got delivered to a
5060 previously considered IP address. Set their status to PENDING_DEFER to indicate
5061 which ones are relevant this time.
5064 addrlist the list of addresses
5065 host the host we are delivering to
5067 Returns: the first address for this delivery
5070 static address_item *
5071 prepare_addresses(address_item *addrlist, host_item *host)
5073 address_item *first_addr = NULL;
5074 for (address_item * addr = addrlist; addr; addr = addr->next)
5075 if (addr->transport_return == DEFER)
5077 if (!first_addr) first_addr = addr;
5078 addr->transport_return = PENDING_DEFER;
5079 addr->basic_errno = 0;
5080 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
5081 addr->message = NULL;
5083 addr->cipher = NULL;
5084 addr->ourcert = NULL;
5085 addr->peercert = NULL;
5086 addr->peerdn = NULL;
5087 addr->ocsp = OCSP_NOT_REQ;
5088 addr->tlsver = NULL;
5090 #ifdef EXPERIMENTAL_DSN_INFO
5091 addr->smtp_greeting = NULL;
5092 addr->helo_response = NULL;
5100 /*************************************************
5101 * Main entry point *
5102 *************************************************/
5104 /* See local README for interface details. As this is a remote transport, it is
5105 given a chain of addresses to be delivered in one connection, if possible. It
5106 always returns TRUE, indicating that each address has its own independent
5107 status set, except if there is a setting up problem, in which case it returns
5111 smtp_transport_entry(
5112 transport_instance *tblock, /* data for this instantiation */
5113 address_item *addrlist) /* addresses we are working on */
5116 int hosts_defer = 0;
5118 int hosts_looked_up = 0;
5119 int hosts_retry = 0;
5120 int hosts_serial = 0;
5121 int hosts_total = 0;
5122 int total_hosts_tried = 0;
5123 BOOL expired = TRUE;
5124 uschar *expanded_hosts = NULL;
5126 uschar *tid = string_sprintf("%s transport", tblock->name);
5127 smtp_transport_options_block *ob = SOB tblock->options_block;
5128 host_item *hostlist = addrlist->host_list;
5129 host_item *host = NULL;
5133 debug_printf("%s transport entered\n", tblock->name);
5134 for (address_item * addr = addrlist; addr; addr = addr->next)
5135 debug_printf(" %s\n", addr->address);
5138 debug_printf("hostlist:\n");
5139 for (host_item * host = hostlist; host; host = host->next)
5140 debug_printf(" '%s' IP %s port %d\n", host->name, host->address, host->port);
5142 if (continue_hostname)
5143 debug_printf("already connected to %s [%s] (on fd %d)\n",
5144 continue_hostname, continue_host_address,
5145 cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0);
5148 /* Check the restrictions on line length */
5150 if (max_received_linelength > ob->message_linelength_limit)
5153 gettimeofday(&now, NULL);
5155 for (address_item * addr = addrlist; addr; addr = addr->next)
5156 if (addr->transport_return == DEFER)
5157 addr->transport_return = PENDING_DEFER;
5159 set_errno_nohost(addrlist, ERRNO_SMTPFORMAT,
5160 US"message has lines too long for transport", FAIL, TRUE, &now);
5164 /* Set the flag requesting that these hosts be added to the waiting
5165 database if the delivery fails temporarily or if we are running with
5166 queue_smtp or a 2-stage queue run. This gets unset for certain
5167 kinds of error, typically those that are specific to the message. */
5169 update_waiting = TRUE;
5171 /* If a host list is not defined for the addresses - they must all have the
5172 same one in order to be passed to a single transport - or if the transport has
5173 a host list with hosts_override set, use the host list supplied with the
5174 transport. It is an error for this not to exist. */
5176 if (!hostlist || (ob->hosts_override && ob->hosts))
5180 addrlist->message = string_sprintf("%s transport called with no hosts set",
5182 addrlist->transport_return = PANIC;
5183 return FALSE; /* Only top address has status */
5186 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
5189 /* If the transport's host list contains no '$' characters, and we are not
5190 randomizing, it is fixed and therefore a chain of hosts can be built once
5191 and for all, and remembered for subsequent use by other calls to this
5192 transport. If, on the other hand, the host list does contain '$', or we are
5193 randomizing its order, we have to rebuild it each time. In the fixed case,
5194 as the hosts string will never be used again, it doesn't matter that we
5195 replace all the : characters with zeros. */
5199 uschar *s = ob->hosts;
5201 if (Ustrchr(s, '$'))
5203 if (!(expanded_hosts = expand_string(s)))
5205 addrlist->message = string_sprintf("failed to expand list of hosts "
5206 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
5207 addrlist->transport_return = f.search_find_defer ? DEFER : PANIC;
5208 return FALSE; /* Only top address has status */
5210 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
5211 "\"%s\"\n", s, expanded_hosts);
5215 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
5219 log_write(0, LOG_MAIN|LOG_PANIC,
5220 "attempt to use tainted host list '%s' from '%s' in transport %s",
5221 s, ob->hosts, tblock->name);
5222 /* Avoid leaking info to an attacker */
5223 addrlist->message = US"internal configuration error";
5224 addrlist->transport_return = PANIC;
5228 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
5230 /* Check that the expansion yielded something useful. */
5234 string_sprintf("%s transport has empty hosts setting", tblock->name);
5235 addrlist->transport_return = PANIC;
5236 return FALSE; /* Only top address has status */
5239 /* If there was no expansion of hosts, save the host list for
5242 if (!expanded_hosts) ob->hostlist = hostlist;
5245 /* This is not the first time this transport has been run in this delivery;
5246 the host list was built previously. */
5249 hostlist = ob->hostlist;
5252 /* The host list was supplied with the address. If hosts_randomize is set, we
5253 must sort it into a random order if it did not come from MX records and has not
5254 already been randomized (but don't bother if continuing down an existing
5257 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
5259 host_item *newlist = NULL;
5262 host_item *h = hostlist;
5263 hostlist = hostlist->next;
5265 h->sort_key = random_number(100);
5272 else if (h->sort_key < newlist->sort_key)
5279 host_item *hh = newlist;
5282 if (h->sort_key < hh->next->sort_key) break;
5290 hostlist = addrlist->host_list = newlist;
5293 /* Sort out the default port. */
5295 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
5297 /* For each host-plus-IP-address on the list:
5299 . If this is a continued delivery and the host isn't the one with the
5300 current connection, skip.
5302 . If the status is unusable (i.e. previously failed or retry checked), skip.
5304 . If no IP address set, get the address, either by turning the name into
5305 an address, calling gethostbyname if gethostbyname is on, or by calling
5306 the DNS. The DNS may yield multiple addresses, in which case insert the
5307 extra ones into the list.
5309 . Get the retry data if not previously obtained for this address and set the
5310 field which remembers the state of this address. Skip if the retry time is
5311 not reached. If not, remember whether retry data was found. The retry string
5312 contains both the name and the IP address.
5314 . Scan the list of addresses and mark those whose status is DEFER as
5315 PENDING_DEFER. These are the only ones that will be processed in this cycle
5318 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
5319 Some addresses may be successfully delivered, others may fail, and yet
5320 others may get temporary errors and so get marked DEFER.
5322 . The return from the delivery attempt is OK if a connection was made and a
5323 valid SMTP dialogue was completed. Otherwise it is DEFER.
5325 . If OK, add a "remove" retry item for this host/IPaddress, if any.
5327 . If fail to connect, or other defer state, add a retry item.
5329 . If there are any addresses whose status is still DEFER, carry on to the
5330 next host/IPaddress, unless we have tried the number of hosts given
5331 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
5332 there is some fancy logic for hosts_max_try that means its limit can be
5333 overstepped in some circumstances.
5335 If we get to the end of the list, all hosts have deferred at least one address,
5336 or not reached their retry times. If delay_after_cutoff is unset, it requests a
5337 delivery attempt to those hosts whose last try was before the arrival time of
5338 the current message. To cope with this, we have to go round the loop a second
5339 time. After that, set the status and error data for any addresses that haven't
5340 had it set already. */
5342 for (int cutoff_retry = 0;
5343 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
5346 host_item *nexthost = NULL;
5347 int unexpired_hosts_tried = 0;
5348 BOOL continue_host_tried = FALSE;
5350 retry_non_continued:
5351 for (host = hostlist;
5353 && unexpired_hosts_tried < ob->hosts_max_try
5354 && total_hosts_tried < ob->hosts_max_try_hardlimit;
5359 BOOL host_is_expired = FALSE;
5360 BOOL message_defer = FALSE;
5361 BOOL some_deferred = FALSE;
5362 address_item *first_addr = NULL;
5363 uschar *interface = NULL;
5364 uschar *retry_host_key = NULL;
5365 uschar *retry_message_key = NULL;
5366 uschar *serialize_key = NULL;
5368 /* Deal slightly better with a possible Linux kernel bug that results
5369 in intermittent TFO-conn fails deep into the TCP flow. Bug 2907 tracks.
5370 Hack: Clear TFO option for any further hosts on this tpt run. */
5372 if (total_hosts_tried > 0)
5374 DEBUG(D_transport|D_acl|D_v)
5375 debug_printf("Clearing TFO as not first host for message\n");
5376 ob->hosts_try_fastopen = US"";
5379 /* Default next host is next host. :-) But this can vary if the
5380 hosts_max_try limit is hit (see below). It may also be reset if a host
5381 address is looked up here (in case the host was multihomed). */
5383 nexthost = host->next;
5385 /* If the address hasn't yet been obtained from the host name, look it up
5386 now, unless the host is already marked as unusable. If it is marked as
5387 unusable, it means that the router was unable to find its IP address (in
5388 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
5389 the lookup failed last time. We don't get this far if *all* MX records
5390 point to non-existent hosts; that is treated as a hard error.
5392 We can just skip this host entirely. When the hosts came from the router,
5393 the address will timeout based on the other host(s); when the address is
5394 looked up below, there is an explicit retry record added.
5396 Note that we mustn't skip unusable hosts if the address is not unset; they
5397 may be needed as expired hosts on the 2nd time round the cutoff loop. */
5401 int new_port, flags;
5403 if (host->status >= hstatus_unusable)
5405 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
5410 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
5412 /* The host name is permitted to have an attached port. Find it, and
5413 strip it from the name. Just remember it for now. */
5415 new_port = host_item_get_port(host);
5417 /* Count hosts looked up */
5421 /* Find by name if so configured, or if it's an IP address. We don't
5422 just copy the IP address, because we need the test-for-local to happen. */
5424 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
5425 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
5426 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
5428 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
5429 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
5431 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
5432 &ob->dnssec, /* domains for request/require */
5435 /* Update the host (and any additional blocks, resulting from
5436 multihoming) with a host-specific port, if any. */
5438 for (host_item * hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
5440 /* Failure to find the host at this time (usually DNS temporary failure)
5441 is really a kind of routing failure rather than a transport failure.
5442 Therefore we add a retry item of the routing kind, not to stop us trying
5443 to look this name up here again, but to ensure the address gets timed
5444 out if the failures go on long enough. A complete failure at this point
5445 commonly points to a configuration error, but the best action is still
5446 to carry on for the next host. */
5448 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
5450 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
5452 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
5453 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
5454 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
5455 host->status = hstatus_unusable;
5457 for (address_item * addr = addrlist; addr; addr = addr->next)
5459 if (addr->transport_return != DEFER) continue;
5460 addr->basic_errno = ERRNO_UNKNOWNHOST;
5461 addr->message = string_sprintf(
5462 rc == HOST_FIND_SECURITY
5463 ? "lookup of IP address for %s was insecure"
5464 : "failed to lookup IP address for %s",
5470 /* If the host is actually the local host, we may have a problem, or
5471 there may be some cunning configuration going on. In the problem case,
5472 log things and give up. The default transport status is already DEFER. */
5474 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
5476 for (address_item * addr = addrlist; addr; addr = addr->next)
5478 addr->basic_errno = ERRNO_HOST_IS_LOCAL;
5479 addr->message = string_sprintf("%s transport found host %s to be "
5480 "local", tblock->name, host->name);
5484 } /* End of block for IP address lookup */
5486 /* If this is a continued delivery, we are interested only in the host
5487 which matches the name of the existing open channel. The check is put
5488 here after the local host lookup, in case the name gets expanded as a
5489 result of the lookup. Set expired FALSE, to save the outer loop executing
5492 if (continue_hostname)
5493 if ( Ustrcmp(continue_hostname, host->name) != 0
5494 || Ustrcmp(continue_host_address, host->address) != 0
5498 continue; /* With next host */
5501 continue_host_tried = TRUE;
5503 /* Reset the default next host in case a multihomed host whose addresses
5504 are not looked up till just above added to the host list. */
5506 nexthost = host->next;
5508 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
5509 domain is in queue_smtp_domains, we don't actually want to attempt any
5510 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
5511 there is a lookup defer in queue_smtp_domains, proceed as if the domain
5512 were not in it. We don't want to hold up all SMTP deliveries! Except when
5513 doing a two-stage queue run, don't do this if forcing. */
5515 if ( (!f.deliver_force || f.queue_2stage)
5517 || match_isinlist(addrlist->domain,
5518 CUSS &queue_smtp_domains, 0,
5519 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK)
5522 DEBUG(D_transport) debug_printf("first-pass routing only\n");
5524 for (address_item * addr = addrlist; addr; addr = addr->next)
5525 if (addr->transport_return == DEFER)
5526 addr->message = US"first-pass only routing due to -odqs, "
5527 "queue_smtp_domains or control=queue";
5528 continue; /* With next host */
5531 /* Count hosts being considered - purely for an intelligent comment
5532 if none are usable. */
5536 /* Set $host and $host address now in case they are needed for the
5537 interface expansion or the serialize_hosts check; they remain set if an
5538 actual delivery happens. */
5540 deliver_host = host->name;
5541 deliver_host_address = host->address;
5542 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
5543 : host->dnssec == DS_NO ? US"no"
5546 /* Set up a string for adding to the retry key if the port number is not
5547 the standard SMTP port. A host may have its own port setting that overrides
5550 pistring = string_sprintf(":%d", host->port == PORT_NONE
5551 ? defport : host->port);
5552 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
5554 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
5555 string is set, even if constant (as different transports can have different
5556 constant settings), we must add it to the key that is used for retries,
5557 because connections to the same host from a different interface should be
5558 treated separately. */
5560 host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
5562 uschar * s = ob->interface;
5565 if (!smtp_get_interface(s, host_af, addrlist, &interface, tid))
5567 pistring = string_sprintf("%s/%s", pistring, interface);
5571 /* The first time round the outer loop, check the status of the host by
5572 inspecting the retry data. The second time round, we are interested only
5573 in expired hosts that haven't been tried since this message arrived. */
5575 if (cutoff_retry == 0)
5578 /* Ensure the status of the address is set by checking retry data if
5579 necessary. There may be host-specific retry data (applicable to all
5580 messages) and also data for retries of a specific message at this host.
5581 If either of these retry records are actually read, the keys used are
5582 returned to save recomputing them later. */
5584 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5585 US"retry_include_ip_address", ob->retry_include_ip_address,
5586 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5587 continue; /* with next host */
5589 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
5590 incl_ip, &retry_host_key, &retry_message_key);
5592 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
5593 host->address ? host->address : US"", pistring,
5594 host->status == hstatus_usable ? "usable"
5595 : host->status == hstatus_unusable ? "unusable"
5596 : host->status == hstatus_unusable_expired ? "unusable (expired)" : "?");
5598 /* Skip this address if not usable at this time, noting if it wasn't
5599 actually expired, both locally and in the address. */
5601 switch (host->status)
5603 case hstatus_unusable:
5605 setflag(addrlist, af_retry_skipped);
5608 case hstatus_unusable_expired:
5611 case hwhy_retry: hosts_retry++; break;
5612 case hwhy_failed: hosts_fail++; break;
5614 case hwhy_deferred: hosts_defer++; break;
5617 /* If there was a retry message key, implying that previously there
5618 was a message-specific defer, we don't want to update the list of
5619 messages waiting for these hosts. */
5621 if (retry_message_key) update_waiting = FALSE;
5622 continue; /* With the next host or IP address */
5626 /* Second time round the loop: if the address is set but expired, and
5627 the message is newer than the last try, let it through. */
5632 || host->status != hstatus_unusable_expired
5633 || host->last_try > received_time.tv_sec)
5635 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
5636 host->name, host->address, pistring);
5637 host_is_expired = TRUE;
5640 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
5641 it remains TRUE only if all hosts are expired and none are actually tried.
5646 /* If this host is listed as one to which access must be serialized,
5647 see if another Exim process has a connection to it, and if so, skip
5648 this host. If not, update the database to record our connection to it
5649 and remember this for later deletion. Do not do any of this if we are
5650 sending the message down a pre-existing connection. */
5652 if ( !continue_hostname
5653 && verify_check_given_host(CUSS &ob->serialize_hosts, host) == OK)
5655 serialize_key = string_sprintf("host-serialize-%s", host->name);
5656 if (!enq_start(serialize_key, 1))
5659 debug_printf("skipping host %s because another Exim process "
5660 "is connected to it\n", host->name);
5666 /* OK, we have an IP address that is not waiting for its retry time to
5667 arrive (it might be expired) OR (second time round the loop) we have an
5668 expired host that hasn't been tried since the message arrived. Have a go
5669 at delivering the message to it. First prepare the addresses by flushing
5670 out the result of previous attempts, and finding the first address that
5671 is still to be delivered. */
5673 first_addr = prepare_addresses(addrlist, host);
5675 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
5676 message_id, host->name, host->address, addrlist->address,
5677 addrlist->next ? ", ..." : "");
5679 set_process_info("delivering %s to %s [%s]%s (%s%s)",
5680 message_id, host->name, host->address, pistring, addrlist->address,
5681 addrlist->next ? ", ..." : "");
5683 /* This is not for real; don't do the delivery. If there are
5684 any remaining hosts, list them. */
5689 gettimeofday(&now, NULL);
5690 set_errno_nohost(addrlist, 0, NULL, OK, FALSE, &now);
5691 for (address_item * addr = addrlist; addr; addr = addr->next)
5693 addr->host_used = host;
5694 addr->special_action = '*';
5695 addr->message = US"delivery bypassed by -N option";
5699 debug_printf("*** delivery by %s transport bypassed by -N option\n"
5700 "*** host and remaining hosts:\n", tblock->name);
5701 for (host_item * host2 = host; host2; host2 = host2->next)
5702 debug_printf(" %s [%s]\n", host2->name,
5703 host2->address ? host2->address : US"unset");
5708 /* This is for real. If the host is expired, we don't count it for
5709 hosts_max_retry. This ensures that all hosts must expire before an address
5710 is timed out, unless hosts_max_try_hardlimit (which protects against
5711 lunatic DNS configurations) is reached.
5713 If the host is not expired and we are about to hit the hosts_max_retry
5714 limit, check to see if there is a subsequent hosts with a different MX
5715 value. If so, make that the next host, and don't count this one. This is a
5716 heuristic to make sure that different MXs do get tried. With a normal kind
5717 of retry rule, they would get tried anyway when the earlier hosts were
5718 delayed, but if the domain has a "retry every time" type of rule - as is
5719 often used for the the very large ISPs, that won't happen. */
5724 /* Make a copy of the host if it is local to this invocation
5725 of the transport. */
5729 thost = store_get(sizeof(host_item), GET_UNTAINTED);
5731 thost->name = string_copy(host->name);
5732 thost->address = string_copy(host->address);
5737 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
5740 debug_printf("hosts_max_try limit reached with this host\n");
5741 for (host_item * h = host; h; h = h->next) if (h->mx != host->mx)
5744 unexpired_hosts_tried--;
5745 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
5746 "and will be tried\n");
5751 /* Attempt the delivery. */
5753 total_hosts_tried++;
5754 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5755 &message_defer, FALSE);
5758 OK => connection made, each address contains its result;
5759 message_defer is set for message-specific defers (when all
5760 recipients are marked defer)
5761 DEFER => there was a non-message-specific delivery problem;
5762 ERROR => there was a problem setting up the arguments for a filter,
5763 or there was a problem with expanding added headers
5766 /* If the result is not OK, there was a non-message-specific problem.
5767 If the result is DEFER, we need to write to the logs saying what happened
5768 for this particular host, except in the case of authentication and TLS
5769 failures, where the log has already been written. If all hosts defer a
5770 general message is written at the end. */
5772 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
5773 && first_addr->basic_errno != ERRNO_TLSFAILURE)
5774 write_logs(host, first_addr->message, first_addr->basic_errno);
5776 #ifndef DISABLE_EVENT
5778 deferred_event_raise(first_addr, host, US"msg:host:defer");
5781 /* If STARTTLS was accepted, but there was a failure in setting up the
5782 TLS session (usually a certificate screwup), and the host is not in
5783 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
5784 TLS forcibly turned off. We have to start from scratch with a new SMTP
5785 connection. That's why the retry is done from here, not from within
5786 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
5787 session, so the in-clear transmission after those errors, if permitted,
5788 happens inside smtp_deliver().] */
5792 && first_addr->basic_errno == ERRNO_TLSFAILURE
5793 && ob->tls_tempfail_tryclear
5794 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
5797 log_write(0, LOG_MAIN,
5798 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
5799 first_addr->message, host->name, host->address);
5800 first_addr = prepare_addresses(addrlist, host);
5801 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
5802 &message_defer, TRUE);
5803 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
5804 write_logs(host, first_addr->message, first_addr->basic_errno);
5805 # ifndef DISABLE_EVENT
5807 deferred_event_raise(first_addr, host, US"msg:host:defer");
5810 #endif /*DISABLE_TLS*/
5812 #ifndef DISABLE_EVENT
5813 /* If the last host gave a defer raise a per-message event */
5816 && unexpired_hosts_tried < ob->hosts_max_try
5817 && total_hosts_tried < ob->hosts_max_try_hardlimit
5819 && (message_defer || rc == DEFER)
5821 deferred_event_raise(first_addr, host, US"msg:defer");
5825 /* Delivery attempt finished */
5827 set_process_info("delivering %s: just tried %s [%s]%s for %s%s: result %s",
5828 message_id, host->name, host->address, pistring, addrlist->address,
5829 addrlist->next ? " (& others)" : "", rc_to_string(rc));
5831 /* Release serialization if set up */
5833 if (serialize_key) enq_end(serialize_key);
5835 /* If the result is DEFER, or if a host retry record is known to exist, we
5836 need to add an item to the retry chain for updating the retry database
5837 at the end of delivery. We only need to add the item to the top address,
5838 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
5839 for any other delivery attempts using the same address. (It is copied into
5840 the unusable tree at the outer level, so even if different address blocks
5841 contain the same address, it still won't get tried again.) */
5843 if (rc == DEFER || retry_host_key)
5845 int delete_flag = rc != DEFER ? rf_delete : 0;
5846 if (!retry_host_key)
5849 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5850 US"retry_include_ip_address", ob->retry_include_ip_address,
5851 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5852 incl_ip = TRUE; /* error; use most-specific retry record */
5854 retry_host_key = incl_ip
5855 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
5856 : string_sprintf("T:%S%s", host->name, pistring);
5859 /* If a delivery of another message over an existing SMTP connection
5860 yields DEFER, we do NOT set up retry data for the host. This covers the
5861 case when there are delays in routing the addresses in the second message
5862 that are so long that the server times out. This is alleviated by not
5863 routing addresses that previously had routing defers when handling an
5864 existing connection, but even so, this case may occur (e.g. if a
5865 previously happily routed address starts giving routing defers). If the
5866 host is genuinely down, another non-continued message delivery will
5867 notice it soon enough. */
5869 if (delete_flag != 0 || !continue_hostname)
5870 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
5872 /* We may have tried an expired host, if its retry time has come; ensure
5873 the status reflects the expiry for the benefit of any other addresses. */
5877 host->status = host_is_expired
5878 ? hstatus_unusable_expired : hstatus_unusable;
5879 host->why = hwhy_deferred;
5883 /* If message_defer is set (host was OK, but every recipient got deferred
5884 because of some message-specific problem), or if that had happened
5885 previously so that a message retry key exists, add an appropriate item
5886 to the retry chain. Note that if there was a message defer but now there is
5887 a host defer, the message defer record gets deleted. That seems perfectly
5888 reasonable. Also, stop the message from being remembered as waiting
5889 for specific hosts. */
5891 if (message_defer || retry_message_key)
5893 int delete_flag = message_defer ? 0 : rf_delete;
5894 if (!retry_message_key)
5897 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
5898 US"retry_include_ip_address", ob->retry_include_ip_address,
5899 ob->expand_retry_include_ip_address, &incl_ip) != OK)
5900 incl_ip = TRUE; /* error; use most-specific retry record */
5902 retry_message_key = incl_ip
5903 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
5905 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
5907 retry_add_item(addrlist, retry_message_key,
5908 rf_message | rf_host | delete_flag);
5909 update_waiting = FALSE;
5912 /* Any return other than DEFER (that is, OK or ERROR) means that the
5913 addresses have got their final statuses filled in for this host. In the OK
5914 case, see if any of them are deferred. */
5917 for (address_item * addr = addrlist; addr; addr = addr->next)
5918 if (addr->transport_return == DEFER)
5920 some_deferred = TRUE;
5924 /* If no addresses deferred or the result was ERROR, return. We do this for
5925 ERROR because a failing filter set-up or add_headers expansion is likely to
5926 fail for any host we try. */
5928 if (rc == ERROR || (rc == OK && !some_deferred))
5930 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
5931 return TRUE; /* Each address has its status */
5934 /* If the result was DEFER or some individual addresses deferred, let
5935 the loop run to try other hosts with the deferred addresses, except for the
5936 case when we were trying to deliver down an existing channel and failed.
5937 Don't try any other hosts in this case. */
5939 if (continue_hostname) break;
5941 /* If the whole delivery, or some individual addresses, were deferred and
5942 there are more hosts that could be tried, do not count this host towards
5943 the hosts_max_try limit if the age of the message is greater than the
5944 maximum retry time for this host. This means we may try try all hosts,
5945 ignoring the limit, when messages have been around for some time. This is
5946 important because if we don't try all hosts, the address will never time
5947 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
5949 if ((rc == DEFER || some_deferred) && nexthost)
5952 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
5954 if (retry && retry->rules)
5956 retry_rule *last_rule;
5957 for (last_rule = retry->rules;
5959 last_rule = last_rule->next);
5960 timedout = time(NULL) - received_time.tv_sec > last_rule->timeout;
5962 else timedout = TRUE; /* No rule => timed out */
5966 unexpired_hosts_tried--;
5967 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
5968 "hosts_max_try (message older than host's retry time)\n");
5974 if (unexpired_hosts_tried >= ob->hosts_max_try)
5975 debug_printf("reached transport hosts_max_try limit %d\n",
5977 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
5978 debug_printf("reached transport hosts_max_try_hardlimit limit %d\n",
5979 ob->hosts_max_try_hardlimit);
5982 testharness_pause_ms(500); /* let server debug out */
5983 } /* End of loop for trying multiple hosts. */
5985 /* If we failed to find a matching host in the list, for an already-open
5986 connection, just close it and start over with the list. This can happen
5987 for routing that changes from run to run, or big multi-IP sites with
5990 if (continue_hostname && !continue_host_tried)
5992 int fd = cutthrough.cctx.sock >= 0 ? cutthrough.cctx.sock : 0;
5994 DEBUG(D_transport) debug_printf("no hosts match already-open connection\n");
5996 /* A TLS conn could be open for a cutthrough, but not for a plain continued-
5998 /*XXX doublecheck that! */
6000 if (cutthrough.cctx.sock >= 0 && cutthrough.is_tls)
6002 (void) tls_write(cutthrough.cctx.tls_ctx, US"QUIT\r\n", 6, FALSE);
6003 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
6004 cutthrough.cctx.tls_ctx = NULL;
6005 cutthrough.is_tls = FALSE;
6009 (void) write(fd, US"QUIT\r\n", 6);
6012 cutthrough.cctx.sock = -1;
6013 continue_hostname = NULL;
6014 goto retry_non_continued;
6017 /* This is the end of the loop that repeats iff expired is TRUE and
6018 ob->delay_after_cutoff is FALSE. The second time round we will
6019 try those hosts that haven't been tried since the message arrived. */
6023 debug_printf("all IP addresses skipped or deferred at least one address\n");
6024 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
6025 debug_printf("retrying IP addresses not tried since message arrived\n");
6030 /* Get here if all IP addresses are skipped or defer at least one address. In
6031 MUA wrapper mode, this will happen only for connection or other non-message-
6032 specific failures. Force the delivery status for all addresses to FAIL. */
6036 for (address_item * addr = addrlist; addr; addr = addr->next)
6037 addr->transport_return = FAIL;
6041 /* In the normal, non-wrapper case, add a standard message to each deferred
6042 address if there hasn't been an error, that is, if it hasn't actually been
6043 tried this time. The variable "expired" will be FALSE if any deliveries were
6044 actually tried, or if there was at least one host that was not expired. That
6045 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
6046 a delivery has been tried, an error code will be set, and the failing of the
6047 message is handled by the retry code later.
6049 If queue_smtp is set, or this transport was called to send a subsequent message
6050 down an existing TCP/IP connection, and something caused the host not to be
6051 found, we end up here, but can detect these cases and handle them specially. */
6053 for (address_item * addr = addrlist; addr; addr = addr->next)
6055 /* If host is not NULL, it means that we stopped processing the host list
6056 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
6057 means we need to behave as if some hosts were skipped because their retry
6058 time had not come. Specifically, this prevents the address from timing out.
6059 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
6060 hosts were tried. */
6063 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
6066 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
6067 "hosts were tried\n");
6072 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
6073 setflag(addr, af_retry_skipped);
6076 if (f.queue_smtp) /* no deliveries attempted */
6078 addr->transport_return = DEFER;
6079 addr->basic_errno = 0;
6080 addr->message = US"SMTP delivery explicitly queued";
6083 else if ( addr->transport_return == DEFER
6084 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
6088 addr->basic_errno = ERRNO_HRETRY;
6089 if (continue_hostname)
6090 addr->message = US"no host found for existing SMTP connection";
6093 setflag(addr, af_pass_message); /* This is not a security risk */
6094 addr->message = string_sprintf(
6095 "all hosts%s have been failing for a long time %s",
6096 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
6097 ob->delay_after_cutoff
6098 ? US"(and retry time not reached)"
6099 : US"and were last tried after this message arrived");
6101 /* If we are already using fallback hosts, or there are no fallback hosts
6102 defined, convert the result to FAIL to cause a bounce. */
6104 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
6105 addr->transport_return = FAIL;
6110 if (hosts_retry == hosts_total)
6111 s = "retry time not reached for any host%s";
6112 else if (hosts_fail == hosts_total)
6113 s = "all host address lookups%s failed permanently";
6114 else if (hosts_defer == hosts_total)
6115 s = "all host address lookups%s failed temporarily";
6116 else if (hosts_serial == hosts_total)
6117 s = "connection limit reached for all hosts%s";
6118 else if (hosts_fail+hosts_defer == hosts_total)
6119 s = "all host address lookups%s failed";
6121 s = "some host address lookups failed and retry time "
6122 "not reached for other hosts or connection limit reached%s";
6124 addr->message = string_sprintf(s,
6125 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
6130 /* Update the database which keeps information about which messages are waiting
6131 for which hosts to become available. For some message-specific errors, the
6132 update_waiting flag is turned off because we don't want follow-on deliveries in
6133 those cases. If this transport instance is explicitly limited to one message
6134 per connection then follow-on deliveries are not possible and there's no need
6135 to create/update the per-transport wait-<transport_name> database. */
6137 if (update_waiting && tblock->connection_max_messages != 1)
6138 transport_update_waiting(hostlist, tblock->name);
6142 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
6144 return TRUE; /* Each address has its status */
6147 #endif /*!MACRO_PREDEF*/
6150 /* End of transport/smtp.c */