1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2009 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Functions concerned with verifying things. The original code for callout
9 caching was contributed by Kevin Fleming (but I hacked it around a bit). */
13 #include "transports/smtp.h"
15 #define CUTTHROUGH_CMD_TIMEOUT 30 /* timeout for cutthrough-routing calls */
16 #define CUTTHROUGH_DATA_TIMEOUT 60 /* timeout for cutthrough-routing calls */
17 address_item cutthrough_addr
;
18 static smtp_outblock ctblock
;
19 uschar ctbuffer
[8192];
22 /* Structure for caching DNSBL lookups */
24 typedef struct dnsbl_cache_block
{
32 /* Anchor for DNSBL cache */
34 static tree_node
*dnsbl_cache
= NULL
;
37 /* Bits for match_type in one_check_dnsbl() */
44 /*************************************************
45 * Retrieve a callout cache record *
46 *************************************************/
48 /* If a record exists, check whether it has expired.
51 dbm_file an open hints file
53 type "address" or "domain"
54 positive_expire expire time for positive records
55 negative_expire expire time for negative records
57 Returns: the cache record if a non-expired one exists, else NULL
60 static dbdata_callout_cache
*
61 get_callout_cache_record(open_db
*dbm_file
, uschar
*key
, uschar
*type
,
62 int positive_expire
, int negative_expire
)
67 dbdata_callout_cache
*cache_record
;
69 cache_record
= dbfn_read_with_length(dbm_file
, key
, &length
);
71 if (cache_record
== NULL
)
73 HDEBUG(D_verify
) debug_printf("callout cache: no %s record found\n", type
);
77 /* We treat a record as "negative" if its result field is not positive, or if
78 it is a domain record and the postmaster field is negative. */
80 negative
= cache_record
->result
!= ccache_accept
||
81 (type
[0] == 'd' && cache_record
->postmaster_result
== ccache_reject
);
82 expire
= negative
? negative_expire
: positive_expire
;
85 if (now
- cache_record
->time_stamp
> expire
)
87 HDEBUG(D_verify
) debug_printf("callout cache: %s record expired\n", type
);
91 /* If this is a non-reject domain record, check for the obsolete format version
92 that doesn't have the postmaster and random timestamps, by looking at the
93 length. If so, copy it to a new-style block, replicating the record's
94 timestamp. Then check the additional timestamps. (There's no point wasting
95 effort if connections are rejected.) */
97 if (type
[0] == 'd' && cache_record
->result
!= ccache_reject
)
99 if (length
== sizeof(dbdata_callout_cache_obs
))
101 dbdata_callout_cache
*new = store_get(sizeof(dbdata_callout_cache
));
102 memcpy(new, cache_record
, length
);
103 new->postmaster_stamp
= new->random_stamp
= new->time_stamp
;
107 if (now
- cache_record
->postmaster_stamp
> expire
)
108 cache_record
->postmaster_result
= ccache_unknown
;
110 if (now
- cache_record
->random_stamp
> expire
)
111 cache_record
->random_result
= ccache_unknown
;
114 HDEBUG(D_verify
) debug_printf("callout cache: found %s record\n", type
);
120 /*************************************************
121 * Do callout verification for an address *
122 *************************************************/
124 /* This function is called from verify_address() when the address has routed to
125 a host list, and a callout has been requested. Callouts are expensive; that is
126 why a cache is used to improve the efficiency.
129 addr the address that's been routed
130 host_list the list of hosts to try
131 tf the transport feedback block
133 ifstring "interface" option from transport, or NULL
134 portstring "port" option from transport, or NULL
135 protocolstring "protocol" option from transport, or NULL
136 callout the per-command callout timeout
137 callout_overall the overall callout timeout (if < 0 use 4*callout)
138 callout_connect the callout connection timeout (if < 0 use callout)
139 options the verification options - these bits are used:
140 vopt_is_recipient => this is a recipient address
141 vopt_callout_no_cache => don't use callout cache
142 vopt_callout_fullpm => if postmaster check, do full one
143 vopt_callout_random => do the "random" thing
144 vopt_callout_recipsender => use real sender for recipient
145 vopt_callout_recippmaster => use postmaster for recipient
146 se_mailfrom MAIL FROM address for sender verify; NULL => ""
147 pm_mailfrom if non-NULL, do the postmaster check with this sender
149 Returns: OK/FAIL/DEFER
153 do_callout(address_item
*addr
, host_item
*host_list
, transport_feedback
*tf
,
154 int callout
, int callout_overall
, int callout_connect
, int options
,
155 uschar
*se_mailfrom
, uschar
*pm_mailfrom
)
157 BOOL is_recipient
= (options
& vopt_is_recipient
) != 0;
158 BOOL callout_no_cache
= (options
& vopt_callout_no_cache
) != 0;
159 BOOL callout_random
= (options
& vopt_callout_random
) != 0;
162 int old_domain_cache_result
= ccache_accept
;
165 uschar
*from_address
;
166 uschar
*random_local_part
= NULL
;
167 uschar
*save_deliver_domain
= deliver_domain
;
168 uschar
**failure_ptr
= is_recipient
?
169 &recipient_verify_failure
: &sender_verify_failure
;
171 open_db
*dbm_file
= NULL
;
172 dbdata_callout_cache new_domain_record
;
173 dbdata_callout_cache_address new_address_record
;
175 time_t callout_start_time
;
177 new_domain_record
.result
= ccache_unknown
;
178 new_domain_record
.postmaster_result
= ccache_unknown
;
179 new_domain_record
.random_result
= ccache_unknown
;
181 memset(&new_address_record
, 0, sizeof(new_address_record
));
183 /* For a recipient callout, the key used for the address cache record must
184 include the sender address if we are using the real sender in the callout,
185 because that may influence the result of the callout. */
187 address_key
= addr
->address
;
192 if ((options
& vopt_callout_recipsender
) != 0)
194 address_key
= string_sprintf("%s/<%s>", addr
->address
, sender_address
);
195 from_address
= sender_address
;
197 else if ((options
& vopt_callout_recippmaster
) != 0)
199 address_key
= string_sprintf("%s/<postmaster@%s>", addr
->address
,
200 qualify_domain_sender
);
201 from_address
= string_sprintf("postmaster@%s", qualify_domain_sender
);
205 /* For a sender callout, we must adjust the key if the mailfrom address is not
210 from_address
= (se_mailfrom
== NULL
)? US
"" : se_mailfrom
;
211 if (from_address
[0] != 0)
212 address_key
= string_sprintf("%s/<%s>", addr
->address
, from_address
);
215 /* Open the callout cache database, it it exists, for reading only at this
216 stage, unless caching has been disabled. */
218 if (callout_no_cache
)
220 HDEBUG(D_verify
) debug_printf("callout cache: disabled by no_cache\n");
222 else if ((dbm_file
= dbfn_open(US
"callout", O_RDWR
, &dbblock
, FALSE
)) == NULL
)
224 HDEBUG(D_verify
) debug_printf("callout cache: not available\n");
227 /* If a cache database is available see if we can avoid the need to do an
228 actual callout by making use of previously-obtained data. */
230 if (dbm_file
!= NULL
)
232 dbdata_callout_cache_address
*cache_address_record
;
233 dbdata_callout_cache
*cache_record
= get_callout_cache_record(dbm_file
,
234 addr
->domain
, US
"domain",
235 callout_cache_domain_positive_expire
,
236 callout_cache_domain_negative_expire
);
238 /* If an unexpired cache record was found for this domain, see if the callout
239 process can be short-circuited. */
241 if (cache_record
!= NULL
)
243 /* In most cases, if an early command (up to and including MAIL FROM:<>)
244 was rejected, there is no point carrying on. The callout fails. However, if
245 we are doing a recipient verification with use_sender or use_postmaster
246 set, a previous failure of MAIL FROM:<> doesn't count, because this time we
247 will be using a non-empty sender. We have to remember this situation so as
248 not to disturb the cached domain value if this whole verification succeeds
249 (we don't want it turning into "accept"). */
251 old_domain_cache_result
= cache_record
->result
;
253 if (cache_record
->result
== ccache_reject
||
254 (*from_address
== 0 && cache_record
->result
== ccache_reject_mfnull
))
256 setflag(addr
, af_verify_nsfail
);
258 debug_printf("callout cache: domain gave initial rejection, or "
259 "does not accept HELO or MAIL FROM:<>\n");
260 setflag(addr
, af_verify_nsfail
);
261 addr
->user_message
= US
"(result of an earlier callout reused).";
263 *failure_ptr
= US
"mail";
267 /* If a previous check on a "random" local part was accepted, we assume
268 that the server does not do any checking on local parts. There is therefore
269 no point in doing the callout, because it will always be successful. If a
270 random check previously failed, arrange not to do it again, but preserve
271 the data in the new record. If a random check is required but hasn't been
272 done, skip the remaining cache processing. */
274 if (callout_random
) switch(cache_record
->random_result
)
278 debug_printf("callout cache: domain accepts random addresses\n");
279 goto END_CALLOUT
; /* Default yield is OK */
283 debug_printf("callout cache: domain rejects random addresses\n");
284 callout_random
= FALSE
;
285 new_domain_record
.random_result
= ccache_reject
;
286 new_domain_record
.random_stamp
= cache_record
->random_stamp
;
291 debug_printf("callout cache: need to check random address handling "
292 "(not cached or cache expired)\n");
296 /* If a postmaster check is requested, but there was a previous failure,
297 there is again no point in carrying on. If a postmaster check is required,
298 but has not been done before, we are going to have to do a callout, so skip
299 remaining cache processing. */
301 if (pm_mailfrom
!= NULL
)
303 if (cache_record
->postmaster_result
== ccache_reject
)
305 setflag(addr
, af_verify_pmfail
);
307 debug_printf("callout cache: domain does not accept "
308 "RCPT TO:<postmaster@domain>\n");
310 *failure_ptr
= US
"postmaster";
311 setflag(addr
, af_verify_pmfail
);
312 addr
->user_message
= US
"(result of earlier verification reused).";
315 if (cache_record
->postmaster_result
== ccache_unknown
)
318 debug_printf("callout cache: need to check RCPT "
319 "TO:<postmaster@domain> (not cached or cache expired)\n");
323 /* If cache says OK, set pm_mailfrom NULL to prevent a redundant
324 postmaster check if the address itself has to be checked. Also ensure
325 that the value in the cache record is preserved (with its old timestamp).
328 HDEBUG(D_verify
) debug_printf("callout cache: domain accepts RCPT "
329 "TO:<postmaster@domain>\n");
331 new_domain_record
.postmaster_result
= ccache_accept
;
332 new_domain_record
.postmaster_stamp
= cache_record
->postmaster_stamp
;
336 /* We can't give a result based on information about the domain. See if there
337 is an unexpired cache record for this specific address (combined with the
338 sender address if we are doing a recipient callout with a non-empty sender).
341 cache_address_record
= (dbdata_callout_cache_address
*)
342 get_callout_cache_record(dbm_file
,
343 address_key
, US
"address",
344 callout_cache_positive_expire
,
345 callout_cache_negative_expire
);
347 if (cache_address_record
!= NULL
)
349 if (cache_address_record
->result
== ccache_accept
)
352 debug_printf("callout cache: address record is positive\n");
357 debug_printf("callout cache: address record is negative\n");
358 addr
->user_message
= US
"Previous (cached) callout verification failure";
359 *failure_ptr
= US
"recipient";
365 /* Close the cache database while we actually do the callout for real. */
368 dbfn_close(dbm_file
);
372 if (!addr
->transport
)
374 HDEBUG(D_verify
) debug_printf("cannot callout via null transport\n");
378 smtp_transport_options_block
*ob
=
379 (smtp_transport_options_block
*)(addr
->transport
->options_block
);
381 /* The information wasn't available in the cache, so we have to do a real
382 callout and save the result in the cache for next time, unless no_cache is set,
383 or unless we have a previously cached negative random result. If we are to test
384 with a random local part, ensure that such a local part is available. If not,
385 log the fact, but carry on without randomming. */
387 if (callout_random
&& callout_random_local_part
!= NULL
)
389 random_local_part
= expand_string(callout_random_local_part
);
390 if (random_local_part
== NULL
)
391 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to expand "
392 "callout_random_local_part: %s", expand_string_message
);
395 /* Default the connect and overall callout timeouts if not set, and record the
396 time we are starting so that we can enforce it. */
398 if (callout_overall
< 0) callout_overall
= 4 * callout
;
399 if (callout_connect
< 0) callout_connect
= callout
;
400 callout_start_time
= time(NULL
);
402 /* Before doing a real callout, if this is an SMTP connection, flush the SMTP
403 output because a callout might take some time. When PIPELINING is active and
404 there are many recipients, the total time for doing lots of callouts can add up
405 and cause the client to time out. So in this case we forgo the PIPELINING
408 if (smtp_out
!= NULL
&& !disable_callout_flush
) mac_smtp_fflush();
410 /* Precompile some regex that are used to recognize parameters in response
411 to an EHLO command, if they aren't already compiled. */
413 if (regex_STARTTLS
== NULL
) regex_STARTTLS
=
414 regex_must_compile(US
"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE
, TRUE
);
417 /* Now make connections to the hosts and do real callouts. The list of hosts
418 is passed in as an argument. */
420 for (host
= host_list
; host
!= NULL
&& !done
; host
= host
->next
)
422 smtp_inblock inblock
;
423 smtp_outblock outblock
;
426 BOOL send_quit
= TRUE
;
427 uschar
*active_hostname
= smtp_active_hostname
;
431 BOOL suppress_tls
= FALSE
;
432 uschar
*interface
= NULL
; /* Outgoing interface to use; NULL => any */
433 uschar inbuffer
[4096];
434 uschar outbuffer
[1024];
435 uschar responsebuffer
[4096];
437 clearflag(addr
, af_verify_pmfail
); /* postmaster callout flag */
438 clearflag(addr
, af_verify_nsfail
); /* null sender callout flag */
440 /* Skip this host if we don't have an IP address for it. */
442 if (host
->address
== NULL
)
444 DEBUG(D_verify
) debug_printf("no IP address for host name %s: skipping\n",
449 /* Check the overall callout timeout */
451 if (time(NULL
) - callout_start_time
>= callout_overall
)
453 HDEBUG(D_verify
) debug_printf("overall timeout for callout exceeded\n");
457 /* Set IPv4 or IPv6 */
459 host_af
= (Ustrchr(host
->address
, ':') == NULL
)? AF_INET
:AF_INET6
;
461 /* Expand and interpret the interface and port strings. The latter will not
462 be used if there is a host-specific port (e.g. from a manualroute router).
463 This has to be delayed till now, because they may expand differently for
464 different hosts. If there's a failure, log it, but carry on with the
467 deliver_host
= host
->name
;
468 deliver_host_address
= host
->address
;
469 deliver_domain
= addr
->domain
;
471 if (!smtp_get_interface(tf
->interface
, host_af
, addr
, NULL
, &interface
,
473 !smtp_get_port(tf
->port
, addr
, &port
, US
"callout"))
474 log_write(0, LOG_MAIN
|LOG_PANIC
, "<%s>: %s", addr
->address
,
477 /* Set HELO string according to the protocol */
478 lmtp
= Ustrcmp(tf
->protocol
, "lmtp") == 0;
479 smtps
= Ustrcmp(tf
->protocol
, "smtps") == 0;
482 HDEBUG(D_verify
) debug_printf("interface=%s port=%d\n", interface
, port
);
484 /* Set up the buffer for reading SMTP response packets. */
486 inblock
.buffer
= inbuffer
;
487 inblock
.buffersize
= sizeof(inbuffer
);
488 inblock
.ptr
= inbuffer
;
489 inblock
.ptrend
= inbuffer
;
491 /* Set up the buffer for holding SMTP commands while pipelining */
493 outblock
.buffer
= outbuffer
;
494 outblock
.buffersize
= sizeof(outbuffer
);
495 outblock
.ptr
= outbuffer
;
496 outblock
.cmd_count
= 0;
497 outblock
.authenticating
= FALSE
;
499 /* Reset the parameters of a TLS session */
500 tls_out
.cipher
= tls_out
.peerdn
= NULL
;
502 /* Connect to the host; on failure, just loop for the next one, but we
503 set the error for the last one. Use the callout_connect timeout. */
505 tls_retry_connection
:
507 inblock
.sock
= outblock
.sock
=
508 smtp_connect(host
, host_af
, port
, interface
, callout_connect
, TRUE
);
509 /* reconsider DSCP here */
510 if (inblock
.sock
< 0)
512 addr
->message
= string_sprintf("could not connect to %s [%s]: %s",
513 host
->name
, host
->address
, strerror(errno
));
514 deliver_host
= deliver_host_address
= NULL
;
515 deliver_domain
= save_deliver_domain
;
519 /* Expand the helo_data string to find the host name to use. */
521 if (tf
->helo_data
!= NULL
)
523 uschar
*s
= expand_string(tf
->helo_data
);
525 log_write(0, LOG_MAIN
|LOG_PANIC
, "<%s>: failed to expand transport's "
526 "helo_data value for callout: %s", addr
->address
,
527 expand_string_message
);
528 else active_hostname
= s
;
531 deliver_host
= deliver_host_address
= NULL
;
532 deliver_domain
= save_deliver_domain
;
534 /* Wait for initial response, and send HELO. The smtp_write_command()
535 function leaves its command in big_buffer. This is used in error responses.
536 Initialize it in case the connection is rejected. */
538 Ustrcpy(big_buffer
, "initial connection");
540 /* Unless ssl-on-connect, wait for the initial greeting */
544 if (!smtps
|| (smtps
&& tls_out
.active
>= 0))
546 if (!(done
= smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
), '2', callout
)))
547 goto RESPONSE_FAILED
;
549 /* Not worth checking greeting line for ESMTP support */
550 if (!(esmtp
= verify_check_this_host(&(ob
->hosts_avoid_esmtp
), NULL
,
551 host
->name
, host
->address
, NULL
) != OK
))
553 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
558 if (smtps
&& tls_out
.active
< 0) /* ssl-on-connect, first pass */
561 ob
->tls_tempfail_tryclear
= FALSE
;
563 else /* all other cases */
568 if (!(done
= smtp_write_command(&outblock
, FALSE
, "%s %s\r\n",
569 !esmtp
? "HELO" : lmtp
? "LHLO" : "EHLO", active_hostname
) >= 0))
571 if (!smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
), '2', callout
))
573 if (errno
!= 0 || responsebuffer
[0] == 0 || lmtp
|| !esmtp
|| tls_out
.active
>= 0)
576 goto RESPONSE_FAILED
;
582 goto esmtp_retry
; /* fallback to HELO */
585 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
587 tls_offered
= esmtp
&& !suppress_tls
&& tls_out
.active
< 0 &&
588 pcre_exec(regex_STARTTLS
, NULL
, CS responsebuffer
, Ustrlen(responsebuffer
), 0,
589 PCRE_EOPT
, NULL
, 0) >= 0;
593 /* If TLS is available on this connection attempt to
594 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
595 send another EHLO - the server may give a different answer in secure mode. We
596 use a separate buffer for reading the response to STARTTLS so that if it is
597 negative, the original EHLO data is available for subsequent analysis, should
598 the client not be required to use TLS. If the response is bad, copy the buffer
599 for error analysis. */
603 verify_check_this_host(&(ob
->hosts_avoid_tls
), NULL
, host
->name
,
604 host
->address
, NULL
) != OK
)
606 uschar buffer2
[4096];
608 && !(done
= smtp_write_command(&outblock
, FALSE
, "STARTTLS\r\n") >= 0))
611 /* If there is an I/O error, transmission of this message is deferred. If
612 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
613 false, we also defer. However, if there is a temporary rejection of STARTTLS
614 and tls_tempfail_tryclear is true, or if there is an outright rejection of
615 STARTTLS, we carry on. This means we will try to send the message in clear,
616 unless the host is in hosts_require_tls (tested below). */
618 if (!smtps
&& !smtp_read_response(&inblock
, buffer2
, sizeof(buffer2
), '2',
619 ob
->command_timeout
))
621 if (errno
!= 0 || buffer2
[0] == 0 ||
622 (buffer2
[0] == '4' && !ob
->tls_tempfail_tryclear
))
624 Ustrncpy(responsebuffer
, buffer2
, sizeof(responsebuffer
));
626 goto RESPONSE_FAILED
;
630 /* STARTTLS accepted or ssl-on-connect: try to negotiate a TLS session. */
633 int rc
= tls_client_start(inblock
.sock
, host
, addr
,
634 NULL
, /* No DH param */
635 ob
->tls_certificate
, ob
->tls_privatekey
,
637 ob
->tls_verify_certificates
, ob
->tls_crl
,
638 ob
->tls_require_ciphers
,
639 ob
->gnutls_require_mac
, ob
->gnutls_require_kx
, ob
->gnutls_require_proto
,
642 /* TLS negotiation failed; give an error. Try in clear on a new connection,
643 if the options permit it for this host. */
646 if (rc
== DEFER
&& ob
->tls_tempfail_tryclear
&& !smtps
&&
647 verify_check_this_host(&(ob
->hosts_require_tls
), NULL
, host
->name
,
648 host
->address
, NULL
) != OK
)
650 (void)close(inblock
.sock
);
651 log_write(0, LOG_MAIN
, "TLS session failure: delivering unencrypted "
652 "to %s [%s] (not in hosts_require_tls)", host
->name
, host
->address
);
654 goto tls_retry_connection
;
656 /*save_errno = ERRNO_TLSFAILURE;*/
657 /*message = US"failure while setting up TLS session";*/
663 /* TLS session is set up. Copy info for logging. */
664 addr
->cipher
= tls_out
.cipher
;
665 addr
->peerdn
= tls_out
.peerdn
;
667 /* For SMTPS we need to wait for the initial OK response, then do HELO. */
669 goto smtps_redo_greeting
;
671 /* For STARTTLS we need to redo EHLO */
676 /* If the host is required to use a secure channel, ensure that we have one. */
677 if (tls_out
.active
< 0)
678 if (verify_check_this_host(&(ob
->hosts_require_tls
), NULL
, host
->name
,
679 host
->address
, NULL
) == OK
)
681 /*save_errno = ERRNO_TLSREQUIRED;*/
682 log_write(0, LOG_MAIN
, "a TLS session is required for %s [%s], but %s",
683 host
->name
, host
->address
,
684 tls_offered
? "an attempt to start TLS failed" : "the server did not offer TLS support");
689 #endif /*SUPPORT_TLS*/
691 done
= TRUE
; /* so far so good; have response to HELO */
693 /*XXX the EHLO response would be analyzed here for IGNOREQUOTA, SIZE, PIPELINING, AUTH */
694 /* If we haven't authenticated, but are required to, give up. */
696 /*XXX "filter command specified for this transport" ??? */
697 /* for now, transport_filter by cutthrough-delivery is not supported */
698 /* Need proper integration with the proper transport mechanism. */
705 /* Clear down of the TLS, SMTP and TCP layers on error is handled below. */
708 /* Failure to accept HELO is cached; this blocks the whole domain for all
709 senders. I/O errors and defer responses are not cached. */
713 *failure_ptr
= US
"mail"; /* At or before MAIL */
714 if (errno
== 0 && responsebuffer
[0] == '5')
716 setflag(addr
, af_verify_nsfail
);
717 new_domain_record
.result
= ccache_reject
;
721 /* Send the MAIL command */
724 smtp_write_command(&outblock
, FALSE
, "MAIL FROM:<%s>\r\n",
725 from_address
) >= 0 &&
726 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
729 /* If the host does not accept MAIL FROM:<>, arrange to cache this
730 information, but again, don't record anything for an I/O error or a defer. Do
731 not cache rejections of MAIL when a non-empty sender has been used, because
732 that blocks the whole domain for all senders. */
736 *failure_ptr
= US
"mail"; /* At or before MAIL */
737 if (errno
== 0 && responsebuffer
[0] == '5')
739 setflag(addr
, af_verify_nsfail
);
740 if (from_address
[0] == 0)
741 new_domain_record
.result
= ccache_reject_mfnull
;
745 /* Otherwise, proceed to check a "random" address (if required), then the
746 given address, and the postmaster address (if required). Between each check,
747 issue RSET, because some servers accept only one recipient after MAIL
750 Before doing this, set the result in the domain cache record to "accept",
751 unless its previous value was ccache_reject_mfnull. In that case, the domain
752 rejects MAIL FROM:<> and we want to continue to remember that. When that is
753 the case, we have got here only in the case of a recipient verification with
754 a non-null sender. */
758 new_domain_record
.result
=
759 (old_domain_cache_result
== ccache_reject_mfnull
)?
760 ccache_reject_mfnull
: ccache_accept
;
762 /* Do the random local part check first */
764 if (random_local_part
!= NULL
)
766 uschar randombuffer
[1024];
768 smtp_write_command(&outblock
, FALSE
,
769 "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part
,
770 addr
->domain
) >= 0 &&
771 smtp_read_response(&inblock
, randombuffer
,
772 sizeof(randombuffer
), '2', callout
);
774 /* Remember when we last did a random test */
776 new_domain_record
.random_stamp
= time(NULL
);
778 /* If accepted, we aren't going to do any further tests below. */
782 new_domain_record
.random_result
= ccache_accept
;
785 /* Otherwise, cache a real negative response, and get back to the right
786 state to send RCPT. Unless there's some problem such as a dropped
787 connection, we expect to succeed, because the commands succeeded above. */
791 if (randombuffer
[0] == '5')
792 new_domain_record
.random_result
= ccache_reject
;
795 smtp_write_command(&outblock
, FALSE
, "RSET\r\n") >= 0 &&
796 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
799 smtp_write_command(&outblock
, FALSE
, "MAIL FROM:<%s>\r\n",
800 from_address
) >= 0 &&
801 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
804 else done
= FALSE
; /* Some timeout/connection problem */
807 /* If the host is accepting all local parts, as determined by the "random"
808 check, we don't need to waste time doing any further checking. */
810 if (new_domain_record
.random_result
!= ccache_accept
&& done
)
812 /* Get the rcpt_include_affixes flag from the transport if there is one,
813 but assume FALSE if there is not. */
816 smtp_write_command(&outblock
, FALSE
, "RCPT TO:<%.1000s>\r\n",
817 transport_rcpt_address(addr
,
818 (addr
->transport
== NULL
)? FALSE
:
819 addr
->transport
->rcpt_include_affixes
)) >= 0 &&
820 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
824 new_address_record
.result
= ccache_accept
;
825 else if (errno
== 0 && responsebuffer
[0] == '5')
827 *failure_ptr
= US
"recipient";
828 new_address_record
.result
= ccache_reject
;
831 /* Do postmaster check if requested; if a full check is required, we
832 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
834 if (done
&& pm_mailfrom
!= NULL
)
836 /*XXX not suitable for cutthrough - sequencing problems */
837 cutthrough_delivery
= FALSE
;
838 HDEBUG(D_acl
|D_v
) debug_printf("Cutthrough cancelled by presence of postmaster verify\n");
841 smtp_write_command(&outblock
, FALSE
, "RSET\r\n") >= 0 &&
842 smtp_read_response(&inblock
, responsebuffer
,
843 sizeof(responsebuffer
), '2', callout
) &&
845 smtp_write_command(&outblock
, FALSE
,
846 "MAIL FROM:<%s>\r\n", pm_mailfrom
) >= 0 &&
847 smtp_read_response(&inblock
, responsebuffer
,
848 sizeof(responsebuffer
), '2', callout
) &&
850 /* First try using the current domain */
853 smtp_write_command(&outblock
, FALSE
,
854 "RCPT TO:<postmaster@%.1000s>\r\n", addr
->domain
) >= 0 &&
855 smtp_read_response(&inblock
, responsebuffer
,
856 sizeof(responsebuffer
), '2', callout
)
861 /* If that doesn't work, and a full check is requested,
862 try without the domain. */
865 (options
& vopt_callout_fullpm
) != 0 &&
866 smtp_write_command(&outblock
, FALSE
,
867 "RCPT TO:<postmaster>\r\n") >= 0 &&
868 smtp_read_response(&inblock
, responsebuffer
,
869 sizeof(responsebuffer
), '2', callout
)
872 /* Sort out the cache record */
874 new_domain_record
.postmaster_stamp
= time(NULL
);
877 new_domain_record
.postmaster_result
= ccache_accept
;
878 else if (errno
== 0 && responsebuffer
[0] == '5')
880 *failure_ptr
= US
"postmaster";
881 setflag(addr
, af_verify_pmfail
);
882 new_domain_record
.postmaster_result
= ccache_reject
;
885 } /* Random not accepted */
886 } /* MAIL FROM: accepted */
888 /* For any failure of the main check, other than a negative response, we just
889 close the connection and carry on. We can identify a negative response by the
890 fact that errno is zero. For I/O errors it will be non-zero
892 Set up different error texts for logging and for sending back to the caller
893 as an SMTP response. Log in all cases, using a one-line format. For sender
894 callouts, give a full response to the caller, but for recipient callouts,
895 don't give the IP address because this may be an internal host whose identity
896 is not to be widely broadcast. */
900 if (errno
== ETIMEDOUT
)
902 HDEBUG(D_verify
) debug_printf("SMTP timeout\n");
907 if (*responsebuffer
== 0) Ustrcpy(responsebuffer
, US
"connection dropped");
910 string_sprintf("response to \"%s\" from %s [%s] was: %s",
911 big_buffer
, host
->name
, host
->address
,
912 string_printing(responsebuffer
));
914 addr
->user_message
= is_recipient
?
915 string_sprintf("Callout verification failed:\n%s", responsebuffer
)
917 string_sprintf("Called: %s\nSent: %s\nResponse: %s",
918 host
->address
, big_buffer
, responsebuffer
);
920 /* Hard rejection ends the process */
922 if (responsebuffer
[0] == '5') /* Address rejected */
930 /* End the SMTP conversation and close the connection. */
932 /* Cutthrough - on a successfull connect and recipient-verify with use-sender
933 and we have no cutthrough conn so far
934 here is where we want to leave the conn open */
935 if ( cutthrough_delivery
938 && (options
& (vopt_callout_recipsender
|vopt_callout_recippmaster
)) == vopt_callout_recipsender
939 && !random_local_part
944 cutthrough_fd
= outblock
.sock
; /* We assume no buffer in use in the outblock */
945 cutthrough_addr
= *addr
; /* Save the address_item for later logging */
946 cutthrough_addr
.host_used
= store_get(sizeof(host_item
));
947 cutthrough_addr
.host_used
->name
= host
->name
;
948 cutthrough_addr
.host_used
->address
= host
->address
;
949 cutthrough_addr
.host_used
->port
= port
;
951 *(cutthrough_addr
.parent
= store_get(sizeof(address_item
)))= *addr
->parent
;
952 ctblock
.buffer
= ctbuffer
;
953 ctblock
.buffersize
= sizeof(ctbuffer
);
954 ctblock
.ptr
= ctbuffer
;
955 /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */
956 ctblock
.sock
= cutthrough_fd
;
960 /* Ensure no cutthrough on multiple address verifies */
961 if (options
& vopt_callout_recipsender
)
962 cancel_cutthrough_connection("multiple verify calls");
963 if (send_quit
) (void)smtp_write_command(&outblock
, FALSE
, "QUIT\r\n");
966 tls_close(FALSE
, TRUE
);
968 (void)close(inblock
.sock
);
971 } /* Loop through all hosts, while !done */
974 /* If we get here with done == TRUE, a successful callout happened, and yield
975 will be set OK or FAIL according to the response to the RCPT command.
976 Otherwise, we looped through the hosts but couldn't complete the business.
977 However, there may be domain-specific information to cache in both cases.
979 The value of the result field in the new_domain record is ccache_unknown if
980 there was an error before or with MAIL FROM:, and errno was not zero,
981 implying some kind of I/O error. We don't want to write the cache in that case.
982 Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
984 if (!callout_no_cache
&& new_domain_record
.result
!= ccache_unknown
)
986 if ((dbm_file
= dbfn_open(US
"callout", O_RDWR
|O_CREAT
, &dbblock
, FALSE
))
989 HDEBUG(D_verify
) debug_printf("callout cache: not available\n");
993 (void)dbfn_write(dbm_file
, addr
->domain
, &new_domain_record
,
994 (int)sizeof(dbdata_callout_cache
));
995 HDEBUG(D_verify
) debug_printf("wrote callout cache domain record:\n"
996 " result=%d postmaster=%d random=%d\n",
997 new_domain_record
.result
,
998 new_domain_record
.postmaster_result
,
999 new_domain_record
.random_result
);
1003 /* If a definite result was obtained for the callout, cache it unless caching
1008 if (!callout_no_cache
&& new_address_record
.result
!= ccache_unknown
)
1010 if (dbm_file
== NULL
)
1011 dbm_file
= dbfn_open(US
"callout", O_RDWR
|O_CREAT
, &dbblock
, FALSE
);
1012 if (dbm_file
== NULL
)
1014 HDEBUG(D_verify
) debug_printf("no callout cache available\n");
1018 (void)dbfn_write(dbm_file
, address_key
, &new_address_record
,
1019 (int)sizeof(dbdata_callout_cache_address
));
1020 HDEBUG(D_verify
) debug_printf("wrote %s callout cache address record\n",
1021 (new_address_record
.result
== ccache_accept
)? "positive" : "negative");
1026 /* Failure to connect to any host, or any response other than 2xx or 5xx is a
1027 temporary error. If there was only one host, and a response was received, leave
1028 it alone if supplying details. Otherwise, give a generic response. */
1032 uschar
*dullmsg
= string_sprintf("Could not complete %s verify callout",
1033 is_recipient
? "recipient" : "sender");
1036 if (host_list
->next
!= NULL
|| addr
->message
== NULL
) addr
->message
= dullmsg
;
1038 addr
->user_message
= (!smtp_return_error_details
)? dullmsg
:
1039 string_sprintf("%s for <%s>.\n"
1040 "The mail server(s) for the domain may be temporarily unreachable, or\n"
1041 "they may be permanently unreachable from this server. In the latter case,\n%s",
1042 dullmsg
, addr
->address
,
1044 "the address will never be accepted."
1046 "you need to change the address or create an MX record for its domain\n"
1047 "if it is supposed to be generally accessible from the Internet.\n"
1048 "Talk to your mail administrator for details.");
1050 /* Force a specific error code */
1052 addr
->basic_errno
= ERRNO_CALLOUTDEFER
;
1055 /* Come here from within the cache-reading code on fast-track exit. */
1058 if (dbm_file
!= NULL
) dbfn_close(dbm_file
);
1064 /* Called after recipient-acl to get a cutthrough connection open when
1065 one was requested and a recipient-verify wasn't subsequently done.
1068 open_cutthrough_connection( address_item
* addr
)
1072 /* Use a recipient-verify-callout to set up the cutthrough connection. */
1073 /* We must use a copy of the address for verification, because it might
1077 HDEBUG(D_acl
) debug_printf("----------- start cutthrough setup ------------\n");
1078 (void) verify_address(&addr2
, NULL
,
1079 vopt_is_recipient
| vopt_callout_recipsender
| vopt_callout_no_cache
,
1080 CUTTHROUGH_CMD_TIMEOUT
, -1, -1,
1082 HDEBUG(D_acl
) debug_printf("----------- end cutthrough setup ------------\n");
1088 /* Send given number of bytes from the buffer */
1090 cutthrough_send(int n
)
1092 if(cutthrough_fd
< 0)
1097 (tls_out
.active
== cutthrough_fd
) ? tls_write(FALSE
, ctblock
.buffer
, n
) :
1099 send(cutthrough_fd
, ctblock
.buffer
, n
, 0) > 0
1102 transport_count
+= n
;
1103 ctblock
.ptr
= ctblock
.buffer
;
1107 HDEBUG(D_transport
|D_acl
) debug_printf("cutthrough_send failed: %s\n", strerror(errno
));
1114 _cutthrough_puts(uschar
* cp
, int n
)
1118 if(ctblock
.ptr
>= ctblock
.buffer
+ctblock
.buffersize
)
1119 if(!cutthrough_send(ctblock
.buffersize
))
1122 *ctblock
.ptr
++ = *cp
++;
1127 /* Buffered output of counted data block. Return boolean success */
1129 cutthrough_puts(uschar
* cp
, int n
)
1131 if (cutthrough_fd
< 0) return TRUE
;
1132 if (_cutthrough_puts(cp
, n
)) return TRUE
;
1133 cancel_cutthrough_connection("transmit failed");
1139 _cutthrough_flush_send( void )
1141 int n
= ctblock
.ptr
-ctblock
.buffer
;
1144 if(!cutthrough_send(n
))
1150 /* Send out any bufferred output. Return boolean success. */
1152 cutthrough_flush_send( void )
1154 if (_cutthrough_flush_send()) return TRUE
;
1155 cancel_cutthrough_connection("transmit failed");
1161 cutthrough_put_nl( void )
1163 return cutthrough_puts(US
"\r\n", 2);
1167 /* Get and check response from cutthrough target */
1169 cutthrough_response(char expect
, uschar
** copy
)
1171 smtp_inblock inblock
;
1172 uschar inbuffer
[4096];
1173 uschar responsebuffer
[4096];
1175 inblock
.buffer
= inbuffer
;
1176 inblock
.buffersize
= sizeof(inbuffer
);
1177 inblock
.ptr
= inbuffer
;
1178 inblock
.ptrend
= inbuffer
;
1179 inblock
.sock
= cutthrough_fd
;
1180 /* this relies on (inblock.sock == tls_out.active) */
1181 if(!smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
), expect
, CUTTHROUGH_DATA_TIMEOUT
))
1182 cancel_cutthrough_connection("target timeout on read");
1187 *copy
= cp
= string_copy(responsebuffer
);
1188 /* Trim the trailing end of line */
1189 cp
+= Ustrlen(responsebuffer
);
1190 if(cp
> *copy
&& cp
[-1] == '\n') *--cp
= '\0';
1191 if(cp
> *copy
&& cp
[-1] == '\r') *--cp
= '\0';
1194 return responsebuffer
[0];
1198 /* Negotiate dataphase with the cutthrough target, returning success boolean */
1200 cutthrough_predata( void )
1202 if(cutthrough_fd
< 0)
1205 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> DATA\n");
1206 cutthrough_puts(US
"DATA\r\n", 6);
1207 cutthrough_flush_send();
1209 /* Assume nothing buffered. If it was it gets ignored. */
1210 return cutthrough_response('3', NULL
) == '3';
1214 /* Buffered send of headers. Return success boolean. */
1215 /* Expands newlines to wire format (CR,NL). */
1216 /* Also sends header-terminating blank line. */
1218 cutthrough_headers_send( void )
1221 uschar
* cp1
, * cp2
;
1223 if(cutthrough_fd
< 0)
1226 for(h
= header_list
; h
!= NULL
; h
= h
->next
)
1227 if(h
->type
!= htype_old
&& h
->text
!= NULL
)
1228 for (cp1
= h
->text
; *cp1
&& (cp2
= Ustrchr(cp1
, '\n')); cp1
= cp2
+1)
1229 if( !cutthrough_puts(cp1
, cp2
-cp1
)
1230 || !cutthrough_put_nl())
1233 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>>(nl)\n");
1234 return cutthrough_put_nl();
1239 close_cutthrough_connection( const char * why
)
1241 if(cutthrough_fd
>= 0)
1243 /* We could be sending this after a bunch of data, but that is ok as
1244 the only way to cancel the transfer in dataphase is to drop the tcp
1245 conn before the final dot.
1247 ctblock
.ptr
= ctbuffer
;
1248 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> QUIT\n");
1249 _cutthrough_puts(US
"QUIT\r\n", 6); /* avoid recursion */
1250 _cutthrough_flush_send();
1251 /* No wait for response */
1254 tls_close(FALSE
, TRUE
);
1256 (void)close(cutthrough_fd
);
1258 HDEBUG(D_acl
) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why
);
1260 ctblock
.ptr
= ctbuffer
;
1264 cancel_cutthrough_connection( const char * why
)
1266 close_cutthrough_connection(why
);
1267 cutthrough_delivery
= FALSE
;
1273 /* Have senders final-dot. Send one to cutthrough target, and grab the response.
1274 Log an OK response as a transmission.
1275 Close the connection.
1276 Return smtp response-class digit.
1279 cutthrough_finaldot( void )
1281 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> .\n");
1283 /* Assume data finshed with new-line */
1284 if(!cutthrough_puts(US
".", 1) || !cutthrough_put_nl() || !cutthrough_flush_send())
1285 return cutthrough_addr
.message
;
1287 switch(cutthrough_response('2', &cutthrough_addr
.message
))
1290 delivery_log(LOG_MAIN
, &cutthrough_addr
, (int)'>', NULL
);
1291 close_cutthrough_connection("delivered");
1295 delivery_log(LOG_MAIN
, &cutthrough_addr
, 0, US
"tmp-reject from cutthrough after DATA:");
1299 delivery_log(LOG_MAIN
|LOG_REJECT
, &cutthrough_addr
, 0, US
"rejected after DATA:");
1305 return cutthrough_addr
.message
;
1310 /*************************************************
1311 * Copy error to toplevel address *
1312 *************************************************/
1314 /* This function is used when a verify fails or defers, to ensure that the
1315 failure or defer information is in the original toplevel address. This applies
1316 when an address is redirected to a single new address, and the failure or
1317 deferral happens to the child address.
1320 vaddr the verify address item
1321 addr the final address item
1324 Returns: the value of YIELD
1328 copy_error(address_item
*vaddr
, address_item
*addr
, int yield
)
1332 vaddr
->message
= addr
->message
;
1333 vaddr
->user_message
= addr
->user_message
;
1334 vaddr
->basic_errno
= addr
->basic_errno
;
1335 vaddr
->more_errno
= addr
->more_errno
;
1336 vaddr
->p
.address_data
= addr
->p
.address_data
;
1337 copyflag(vaddr
, addr
, af_pass_message
);
1345 /**************************************************
1346 * printf that automatically handles TLS if needed *
1347 ***************************************************/
1349 /* This function is used by verify_address() as a substitute for all fprintf()
1350 calls; a direct fprintf() will not produce output in a TLS SMTP session, such
1351 as a response to an EXPN command. smtp_in.c makes smtp_printf available but
1352 that assumes that we always use the smtp_out FILE* when not using TLS or the
1353 ssl buffer when we are. Instead we take a FILE* parameter and check to see if
1354 that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular
1358 f the candidate FILE* to write to
1359 format format string
1360 ... optional arguments
1366 static void PRINTF_FUNCTION(2,3)
1367 respond_printf(FILE *f
, const char *format
, ...)
1371 va_start(ap
, format
);
1372 if (smtp_out
&& (f
== smtp_out
))
1373 smtp_vprintf(format
, ap
);
1375 vfprintf(f
, format
, ap
);
1381 /*************************************************
1382 * Verify an email address *
1383 *************************************************/
1385 /* This function is used both for verification (-bv and at other times) and
1386 address testing (-bt), which is indicated by address_test_mode being set.
1389 vaddr contains the address to verify; the next field in this block
1391 f if not NULL, write the result to this file
1392 options various option bits:
1393 vopt_fake_sender => this sender verify is not for the real
1394 sender (it was verify=sender=xxxx or an address from a
1395 header line) - rewriting must not change sender_address
1396 vopt_is_recipient => this is a recipient address, otherwise
1397 it's a sender address - this affects qualification and
1398 rewriting and messages from callouts
1399 vopt_qualify => qualify an unqualified address; else error
1400 vopt_expn => called from SMTP EXPN command
1401 vopt_success_on_redirect => when a new address is generated
1402 the verification instantly succeeds
1404 These ones are used by do_callout() -- the options variable
1407 vopt_callout_fullpm => if postmaster check, do full one
1408 vopt_callout_no_cache => don't use callout cache
1409 vopt_callout_random => do the "random" thing
1410 vopt_callout_recipsender => use real sender for recipient
1411 vopt_callout_recippmaster => use postmaster for recipient
1413 callout if > 0, specifies that callout is required, and gives timeout
1414 for individual commands
1415 callout_overall if > 0, gives overall timeout for the callout function;
1416 if < 0, a default is used (see do_callout())
1417 callout_connect the connection timeout for callouts
1418 se_mailfrom when callout is requested to verify a sender, use this
1419 in MAIL FROM; NULL => ""
1420 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
1421 thing and use this as the sender address (may be "")
1423 routed if not NULL, set TRUE if routing succeeded, so we can
1424 distinguish between routing failed and callout failed
1426 Returns: OK address verified
1427 FAIL address failed to verify
1428 DEFER can't tell at present
1432 verify_address(address_item
*vaddr
, FILE *f
, int options
, int callout
,
1433 int callout_overall
, int callout_connect
, uschar
*se_mailfrom
,
1434 uschar
*pm_mailfrom
, BOOL
*routed
)
1437 BOOL full_info
= (f
== NULL
)? FALSE
: (debug_selector
!= 0);
1438 BOOL is_recipient
= (options
& vopt_is_recipient
) != 0;
1439 BOOL expn
= (options
& vopt_expn
) != 0;
1440 BOOL success_on_redirect
= (options
& vopt_success_on_redirect
) != 0;
1443 int verify_type
= expn
? v_expn
:
1444 address_test_mode
? v_none
:
1445 is_recipient
? v_recipient
: v_sender
;
1446 address_item
*addr_list
;
1447 address_item
*addr_new
= NULL
;
1448 address_item
*addr_remote
= NULL
;
1449 address_item
*addr_local
= NULL
;
1450 address_item
*addr_succeed
= NULL
;
1451 uschar
**failure_ptr
= is_recipient
?
1452 &recipient_verify_failure
: &sender_verify_failure
;
1453 uschar
*ko_prefix
, *cr
;
1454 uschar
*address
= vaddr
->address
;
1455 uschar
*save_sender
;
1456 uschar null_sender
[] = { 0 }; /* Ensure writeable memory */
1458 /* Clear, just in case */
1460 *failure_ptr
= NULL
;
1462 /* Set up a prefix and suffix for error message which allow us to use the same
1463 output statements both in EXPN mode (where an SMTP response is needed) and when
1464 debugging with an output file. */
1468 ko_prefix
= US
"553 ";
1471 else ko_prefix
= cr
= US
"";
1473 /* Add qualify domain if permitted; otherwise an unqualified address fails. */
1475 if (parse_find_at(address
) == NULL
)
1477 if ((options
& vopt_qualify
) == 0)
1480 respond_printf(f
, "%sA domain is required for \"%s\"%s\n",
1481 ko_prefix
, address
, cr
);
1482 *failure_ptr
= US
"qualify";
1485 address
= rewrite_address_qualify(address
, is_recipient
);
1490 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1491 debug_printf("%s %s\n", address_test_mode
? "Testing" : "Verifying", address
);
1494 /* Rewrite and report on it. Clear the domain and local part caches - these
1495 may have been set by domains and local part tests during an ACL. */
1497 if (global_rewrite_rules
!= NULL
)
1499 uschar
*old
= address
;
1500 address
= rewrite_address(address
, is_recipient
, FALSE
,
1501 global_rewrite_rules
, rewrite_existflags
);
1504 for (i
= 0; i
< (MAX_NAMED_LIST
* 2)/32; i
++) vaddr
->localpart_cache
[i
] = 0;
1505 for (i
= 0; i
< (MAX_NAMED_LIST
* 2)/32; i
++) vaddr
->domain_cache
[i
] = 0;
1506 if (f
!= NULL
&& !expn
) fprintf(f
, "Address rewritten as: %s\n", address
);
1510 /* If this is the real sender address, we must update sender_address at
1511 this point, because it may be referred to in the routers. */
1513 if ((options
& (vopt_fake_sender
|vopt_is_recipient
)) == 0)
1514 sender_address
= address
;
1516 /* If the address was rewritten to <> no verification can be done, and we have
1517 to return OK. This rewriting is permitted only for sender addresses; for other
1518 addresses, such rewriting fails. */
1520 if (address
[0] == 0) return OK
;
1522 /* Save a copy of the sender address for re-instating if we change it to <>
1523 while verifying a sender address (a nice bit of self-reference there). */
1525 save_sender
= sender_address
;
1527 /* Update the address structure with the possibly qualified and rewritten
1528 address. Set it up as the starting address on the chain of new addresses. */
1530 vaddr
->address
= address
;
1533 /* We need a loop, because an address can generate new addresses. We must also
1534 cope with generated pipes and files at the top level. (See also the code and
1535 comment in deliver.c.) However, it is usually the case that the router for
1536 user's .forward files has its verify flag turned off.
1538 If an address generates more than one child, the loop is used only when
1539 full_info is set, and this can only be set locally. Remote enquiries just get
1540 information about the top level address, not anything that it generated. */
1542 while (addr_new
!= NULL
)
1545 address_item
*addr
= addr_new
;
1547 addr_new
= addr
->next
;
1552 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1553 debug_printf("Considering %s\n", addr
->address
);
1556 /* Handle generated pipe, file or reply addresses. We don't get these
1557 when handling EXPN, as it does only one level of expansion. */
1559 if (testflag(addr
, af_pfr
))
1566 if (addr
->address
[0] == '>')
1568 allow
= testflag(addr
, af_allow_reply
);
1569 fprintf(f
, "%s -> mail %s", addr
->parent
->address
, addr
->address
+ 1);
1573 allow
= (addr
->address
[0] == '|')?
1574 testflag(addr
, af_allow_pipe
) : testflag(addr
, af_allow_file
);
1575 fprintf(f
, "%s -> %s", addr
->parent
->address
, addr
->address
);
1578 if (addr
->basic_errno
== ERRNO_BADTRANSPORT
)
1579 fprintf(f
, "\n*** Error in setting up pipe, file, or autoreply:\n"
1580 "%s\n", addr
->message
);
1582 fprintf(f
, "\n transport = %s\n", addr
->transport
->name
);
1584 fprintf(f
, " *** forbidden ***\n");
1589 /* Just in case some router parameter refers to it. */
1591 return_path
= (addr
->p
.errors_address
!= NULL
)?
1592 addr
->p
.errors_address
: sender_address
;
1594 /* Split the address into domain and local part, handling the %-hack if
1595 necessary, and then route it. While routing a sender address, set
1596 $sender_address to <> because that is what it will be if we were trying to
1597 send a bounce to the sender. */
1599 if (routed
!= NULL
) *routed
= FALSE
;
1600 if ((rc
= deliver_split_address(addr
)) == OK
)
1602 if (!is_recipient
) sender_address
= null_sender
;
1603 rc
= route_address(addr
, &addr_local
, &addr_remote
, &addr_new
,
1604 &addr_succeed
, verify_type
);
1605 sender_address
= save_sender
; /* Put back the real sender */
1608 /* If routing an address succeeded, set the flag that remembers, for use when
1609 an ACL cached a sender verify (in case a callout fails). Then if routing set
1610 up a list of hosts or the transport has a host list, and the callout option
1611 is set, and we aren't in a host checking run, do the callout verification,
1612 and set another flag that notes that a callout happened. */
1616 if (routed
!= NULL
) *routed
= TRUE
;
1619 host_item
*host_list
= addr
->host_list
;
1621 /* Make up some data for use in the case where there is no remote
1624 transport_feedback tf
= {
1625 NULL
, /* interface (=> any) */
1626 US
"smtp", /* port */
1627 US
"smtp", /* protocol */
1629 US
"$smtp_active_hostname", /* helo_data */
1630 FALSE
, /* hosts_override */
1631 FALSE
, /* hosts_randomize */
1632 FALSE
, /* gethostbyname */
1633 TRUE
, /* qualify_single */
1634 FALSE
/* search_parents */
1637 /* If verification yielded a remote transport, we want to use that
1638 transport's options, so as to mimic what would happen if we were really
1639 sending a message to this address. */
1641 if (addr
->transport
!= NULL
&& !addr
->transport
->info
->local
)
1643 (void)(addr
->transport
->setup
)(addr
->transport
, addr
, &tf
, 0, 0, NULL
);
1645 /* If the transport has hosts and the router does not, or if the
1646 transport is configured to override the router's hosts, we must build a
1647 host list of the transport's hosts, and find the IP addresses */
1649 if (tf
.hosts
!= NULL
&& (host_list
== NULL
|| tf
.hosts_override
))
1652 uschar
*save_deliver_domain
= deliver_domain
;
1653 uschar
*save_deliver_localpart
= deliver_localpart
;
1655 host_list
= NULL
; /* Ignore the router's hosts */
1657 deliver_domain
= addr
->domain
;
1658 deliver_localpart
= addr
->local_part
;
1659 s
= expand_string(tf
.hosts
);
1660 deliver_domain
= save_deliver_domain
;
1661 deliver_localpart
= save_deliver_localpart
;
1665 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to expand list of hosts "
1666 "\"%s\" in %s transport for callout: %s", tf
.hosts
,
1667 addr
->transport
->name
, expand_string_message
);
1672 uschar
*canonical_name
;
1673 host_item
*host
, *nexthost
;
1674 host_build_hostlist(&host_list
, s
, tf
.hosts_randomize
);
1676 /* Just ignore failures to find a host address. If we don't manage
1677 to find any addresses, the callout will defer. Note that more than
1678 one address may be found for a single host, which will result in
1679 additional host items being inserted into the chain. Hence we must
1680 save the next host first. */
1682 flags
= HOST_FIND_BY_A
;
1683 if (tf
.qualify_single
) flags
|= HOST_FIND_QUALIFY_SINGLE
;
1684 if (tf
.search_parents
) flags
|= HOST_FIND_SEARCH_PARENTS
;
1686 for (host
= host_list
; host
!= NULL
; host
= nexthost
)
1688 nexthost
= host
->next
;
1689 if (tf
.gethostbyname
||
1690 string_is_ip_address(host
->name
, NULL
) != 0)
1691 (void)host_find_byname(host
, NULL
, flags
, &canonical_name
, TRUE
);
1693 (void)host_find_bydns(host
, NULL
, flags
, NULL
, NULL
, NULL
,
1694 &canonical_name
, NULL
);
1700 /* Can only do a callout if we have at least one host! If the callout
1701 fails, it will have set ${sender,recipient}_verify_failure. */
1703 if (host_list
!= NULL
)
1705 HDEBUG(D_verify
) debug_printf("Attempting full verification using callout\n");
1706 if (host_checking
&& !host_checking_callout
)
1709 debug_printf("... callout omitted by default when host testing\n"
1710 "(Use -bhc if you want the callouts to happen.)\n");
1714 rc
= do_callout(addr
, host_list
, &tf
, callout
, callout_overall
,
1715 callout_connect
, options
, se_mailfrom
, pm_mailfrom
);
1720 HDEBUG(D_verify
) debug_printf("Cannot do callout: neither router nor "
1721 "transport provided a host list\n");
1726 /* Otherwise, any failure is a routing failure */
1728 else *failure_ptr
= US
"route";
1730 /* A router may return REROUTED if it has set up a child address as a result
1731 of a change of domain name (typically from widening). In this case we always
1732 want to continue to verify the new child. */
1734 if (rc
== REROUTED
) continue;
1736 /* Handle hard failures */
1743 address_item
*p
= addr
->parent
;
1745 respond_printf(f
, "%s%s %s", ko_prefix
,
1746 full_info
? addr
->address
: address
,
1747 address_test_mode
? "is undeliverable" : "failed to verify");
1748 if (!expn
&& admin_user
)
1750 if (addr
->basic_errno
> 0)
1751 respond_printf(f
, ": %s", strerror(addr
->basic_errno
));
1752 if (addr
->message
!= NULL
)
1753 respond_printf(f
, ": %s", addr
->message
);
1756 /* Show parents iff doing full info */
1758 if (full_info
) while (p
!= NULL
)
1760 respond_printf(f
, "%s\n <-- %s", cr
, p
->address
);
1763 respond_printf(f
, "%s\n", cr
);
1765 cancel_cutthrough_connection("routing hard fail");
1767 if (!full_info
) return copy_error(vaddr
, addr
, FAIL
);
1773 else if (rc
== DEFER
)
1778 address_item
*p
= addr
->parent
;
1779 respond_printf(f
, "%s%s cannot be resolved at this time", ko_prefix
,
1780 full_info
? addr
->address
: address
);
1781 if (!expn
&& admin_user
)
1783 if (addr
->basic_errno
> 0)
1784 respond_printf(f
, ": %s", strerror(addr
->basic_errno
));
1785 if (addr
->message
!= NULL
)
1786 respond_printf(f
, ": %s", addr
->message
);
1787 else if (addr
->basic_errno
<= 0)
1788 respond_printf(f
, ": unknown error");
1791 /* Show parents iff doing full info */
1793 if (full_info
) while (p
!= NULL
)
1795 respond_printf(f
, "%s\n <-- %s", cr
, p
->address
);
1798 respond_printf(f
, "%s\n", cr
);
1800 cancel_cutthrough_connection("routing soft fail");
1802 if (!full_info
) return copy_error(vaddr
, addr
, DEFER
);
1803 else if (yield
== OK
) yield
= DEFER
;
1806 /* If we are handling EXPN, we do not want to continue to route beyond
1807 the top level (whose address is in "address"). */
1811 uschar
*ok_prefix
= US
"250-";
1812 if (addr_new
== NULL
)
1814 if (addr_local
== NULL
&& addr_remote
== NULL
)
1815 respond_printf(f
, "250 mail to <%s> is discarded\r\n", address
);
1817 respond_printf(f
, "250 <%s>\r\n", address
);
1819 else while (addr_new
!= NULL
)
1821 address_item
*addr2
= addr_new
;
1822 addr_new
= addr2
->next
;
1823 if (addr_new
== NULL
) ok_prefix
= US
"250 ";
1824 respond_printf(f
, "%s<%s>\r\n", ok_prefix
, addr2
->address
);
1829 /* Successful routing other than EXPN. */
1833 /* Handle successful routing when short info wanted. Otherwise continue for
1834 other (generated) addresses. Short info is the operational case. Full info
1835 can be requested only when debug_selector != 0 and a file is supplied.
1837 There is a conflict between the use of aliasing as an alternate email
1838 address, and as a sort of mailing list. If an alias turns the incoming
1839 address into just one address (e.g. J.Caesar->jc44) you may well want to
1840 carry on verifying the generated address to ensure it is valid when
1841 checking incoming mail. If aliasing generates multiple addresses, you
1842 probably don't want to do this. Exim therefore treats the generation of
1843 just a single new address as a special case, and continues on to verify the
1844 generated address. */
1846 if (!full_info
&& /* Stop if short info wanted AND */
1847 (((addr_new
== NULL
|| /* No new address OR */
1848 addr_new
->next
!= NULL
|| /* More than one new address OR */
1849 testflag(addr_new
, af_pfr
))) /* New address is pfr */
1851 (addr_new
!= NULL
&& /* At least one new address AND */
1852 success_on_redirect
))) /* success_on_redirect is set */
1854 if (f
!= NULL
) fprintf(f
, "%s %s\n", address
,
1855 address_test_mode
? "is deliverable" : "verified");
1857 /* If we have carried on to verify a child address, we want the value
1858 of $address_data to be that of the child */
1860 vaddr
->p
.address_data
= addr
->p
.address_data
;
1864 } /* Loop for generated addresses */
1866 /* Display the full results of the successful routing, including any generated
1867 addresses. Control gets here only when full_info is set, which requires f not
1868 to be NULL, and this occurs only when a top-level verify is called with the
1869 debugging switch on.
1871 If there are no local and no remote addresses, and there were no pipes, files,
1872 or autoreplies, and there were no errors or deferments, the message is to be
1873 discarded, usually because of the use of :blackhole: in an alias file. */
1875 if (allok
&& addr_local
== NULL
&& addr_remote
== NULL
)
1877 fprintf(f
, "mail to %s is discarded\n", address
);
1881 for (addr_list
= addr_local
, i
= 0; i
< 2; addr_list
= addr_remote
, i
++)
1883 while (addr_list
!= NULL
)
1885 address_item
*addr
= addr_list
;
1886 address_item
*p
= addr
->parent
;
1887 addr_list
= addr
->next
;
1889 fprintf(f
, "%s", CS addr
->address
);
1890 #ifdef EXPERIMENTAL_SRS
1891 if(addr
->p
.srs_sender
)
1892 fprintf(f
, " [srs = %s]", addr
->p
.srs_sender
);
1895 /* If the address is a duplicate, show something about it. */
1897 if (!testflag(addr
, af_pfr
))
1900 if ((tnode
= tree_search(tree_duplicates
, addr
->unique
)) != NULL
)
1901 fprintf(f
, " [duplicate, would not be delivered]");
1902 else tree_add_duplicate(addr
->unique
, addr
);
1905 /* Now show its parents */
1909 fprintf(f
, "\n <-- %s", p
->address
);
1914 /* Show router, and transport */
1916 fprintf(f
, "router = %s, ", addr
->router
->name
);
1917 fprintf(f
, "transport = %s\n", (addr
->transport
== NULL
)? US
"unset" :
1918 addr
->transport
->name
);
1920 /* Show any hosts that are set up by a router unless the transport
1921 is going to override them; fiddle a bit to get a nice format. */
1923 if (addr
->host_list
!= NULL
&& addr
->transport
!= NULL
&&
1924 !addr
->transport
->overrides_hosts
)
1929 for (h
= addr
->host_list
; h
!= NULL
; h
= h
->next
)
1931 int len
= Ustrlen(h
->name
);
1932 if (len
> maxlen
) maxlen
= len
;
1933 len
= (h
->address
!= NULL
)? Ustrlen(h
->address
) : 7;
1934 if (len
> maxaddlen
) maxaddlen
= len
;
1936 for (h
= addr
->host_list
; h
!= NULL
; h
= h
->next
)
1938 int len
= Ustrlen(h
->name
);
1939 fprintf(f
, " host %s ", h
->name
);
1940 while (len
++ < maxlen
) fprintf(f
, " ");
1941 if (h
->address
!= NULL
)
1943 fprintf(f
, "[%s] ", h
->address
);
1944 len
= Ustrlen(h
->address
);
1946 else if (!addr
->transport
->info
->local
) /* Omit [unknown] for local */
1948 fprintf(f
, "[unknown] ");
1952 while (len
++ < maxaddlen
) fprintf(f
," ");
1953 if (h
->mx
>= 0) fprintf(f
, "MX=%d", h
->mx
);
1954 if (h
->port
!= PORT_NONE
) fprintf(f
, " port=%d", h
->port
);
1955 if (h
->status
== hstatus_unusable
) fprintf(f
, " ** unusable **");
1962 /* Will be DEFER or FAIL if any one address has, only for full_info (which is
1963 the -bv or -bt case). */
1971 /*************************************************
1972 * Check headers for syntax errors *
1973 *************************************************/
1975 /* This function checks those header lines that contain addresses, and verifies
1976 that all the addresses therein are syntactially correct.
1979 msgptr where to put an error message
1986 verify_check_headers(uschar
**msgptr
)
1992 for (h
= header_list
; h
!= NULL
&& yield
== OK
; h
= h
->next
)
1994 if (h
->type
!= htype_from
&&
1995 h
->type
!= htype_reply_to
&&
1996 h
->type
!= htype_sender
&&
1997 h
->type
!= htype_to
&&
1998 h
->type
!= htype_cc
&&
1999 h
->type
!= htype_bcc
)
2002 colon
= Ustrchr(h
->text
, ':');
2004 while (isspace(*s
)) s
++;
2006 /* Loop for multiple addresses in the header, enabling group syntax. Note
2007 that we have to reset this after the header has been scanned. */
2009 parse_allow_group
= TRUE
;
2013 uschar
*ss
= parse_find_address_end(s
, FALSE
);
2014 uschar
*recipient
, *errmess
;
2015 int terminator
= *ss
;
2016 int start
, end
, domain
;
2018 /* Temporarily terminate the string at this point, and extract the
2019 operative address within, allowing group syntax. */
2022 recipient
= parse_extract_address(s
,&errmess
,&start
,&end
,&domain
,FALSE
);
2025 /* Permit an unqualified address only if the message is local, or if the
2026 sending host is configured to be permitted to send them. */
2028 if (recipient
!= NULL
&& domain
== 0)
2030 if (h
->type
== htype_from
|| h
->type
== htype_sender
)
2032 if (!allow_unqualified_sender
) recipient
= NULL
;
2036 if (!allow_unqualified_recipient
) recipient
= NULL
;
2038 if (recipient
== NULL
) errmess
= US
"unqualified address not permitted";
2041 /* It's an error if no address could be extracted, except for the special
2042 case of an empty address. */
2044 if (recipient
== NULL
&& Ustrcmp(errmess
, "empty address") != 0)
2046 uschar
*verb
= US
"is";
2051 /* Arrange not to include any white space at the end in the
2052 error message or the header name. */
2054 while (t
> s
&& isspace(t
[-1])) t
--;
2055 while (tt
> h
->text
&& isspace(tt
[-1])) tt
--;
2057 /* Add the address that failed to the error message, since in a
2058 header with very many addresses it is sometimes hard to spot
2059 which one is at fault. However, limit the amount of address to
2060 quote - cases have been seen where, for example, a missing double
2061 quote in a humungous To: header creates an "address" that is longer
2062 than string_sprintf can handle. */
2071 *msgptr
= string_printing(
2072 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
2073 errmess
, tt
- h
->text
, h
->text
, verb
, len
, s
));
2076 break; /* Out of address loop */
2079 /* Advance to the next address */
2081 s
= ss
+ (terminator
? 1:0);
2082 while (isspace(*s
)) s
++;
2083 } /* Next address */
2085 parse_allow_group
= FALSE
;
2086 parse_found_group
= FALSE
;
2087 } /* Next header unless yield has been set FALSE */
2094 /*************************************************
2095 * Check for blind recipients *
2096 *************************************************/
2098 /* This function checks that every (envelope) recipient is mentioned in either
2099 the To: or Cc: header lines, thus detecting blind carbon copies.
2101 There are two ways of scanning that could be used: either scan the header lines
2102 and tick off the recipients, or scan the recipients and check the header lines.
2103 The original proposed patch did the former, but I have chosen to do the latter,
2104 because (a) it requires no memory and (b) will use fewer resources when there
2105 are many addresses in To: and/or Cc: and only one or two envelope recipients.
2108 Returns: OK if there are no blind recipients
2109 FAIL if there is at least one blind recipient
2113 verify_check_notblind(void)
2116 for (i
= 0; i
< recipients_count
; i
++)
2120 uschar
*address
= recipients_list
[i
].address
;
2122 for (h
= header_list
; !found
&& h
!= NULL
; h
= h
->next
)
2126 if (h
->type
!= htype_to
&& h
->type
!= htype_cc
) continue;
2128 colon
= Ustrchr(h
->text
, ':');
2130 while (isspace(*s
)) s
++;
2132 /* Loop for multiple addresses in the header, enabling group syntax. Note
2133 that we have to reset this after the header has been scanned. */
2135 parse_allow_group
= TRUE
;
2139 uschar
*ss
= parse_find_address_end(s
, FALSE
);
2140 uschar
*recipient
,*errmess
;
2141 int terminator
= *ss
;
2142 int start
, end
, domain
;
2144 /* Temporarily terminate the string at this point, and extract the
2145 operative address within, allowing group syntax. */
2148 recipient
= parse_extract_address(s
,&errmess
,&start
,&end
,&domain
,FALSE
);
2151 /* If we found a valid recipient that has a domain, compare it with the
2152 envelope recipient. Local parts are compared case-sensitively, domains
2153 case-insensitively. By comparing from the start with length "domain", we
2154 include the "@" at the end, which ensures that we are comparing the whole
2155 local part of each address. */
2157 if (recipient
!= NULL
&& domain
!= 0)
2159 found
= Ustrncmp(recipient
, address
, domain
) == 0 &&
2160 strcmpic(recipient
+ domain
, address
+ domain
) == 0;
2164 /* Advance to the next address */
2166 s
= ss
+ (terminator
? 1:0);
2167 while (isspace(*s
)) s
++;
2168 } /* Next address */
2170 parse_allow_group
= FALSE
;
2171 parse_found_group
= FALSE
;
2172 } /* Next header (if found is false) */
2174 if (!found
) return FAIL
;
2175 } /* Next recipient */
2182 /*************************************************
2183 * Find if verified sender *
2184 *************************************************/
2186 /* Usually, just a single address is verified as the sender of the message.
2187 However, Exim can be made to verify other addresses as well (often related in
2188 some way), and this is useful in some environments. There may therefore be a
2189 chain of such addresses that have previously been tested. This function finds
2190 whether a given address is on the chain.
2192 Arguments: the address to be verified
2193 Returns: pointer to an address item, or NULL
2197 verify_checked_sender(uschar
*sender
)
2200 for (addr
= sender_verified_list
; addr
!= NULL
; addr
= addr
->next
)
2201 if (Ustrcmp(sender
, addr
->address
) == 0) break;
2209 /*************************************************
2210 * Get valid header address *
2211 *************************************************/
2213 /* Scan the originator headers of the message, looking for an address that
2214 verifies successfully. RFC 822 says:
2216 o The "Sender" field mailbox should be sent notices of
2217 any problems in transport or delivery of the original
2218 messages. If there is no "Sender" field, then the
2219 "From" field mailbox should be used.
2221 o If the "Reply-To" field exists, then the reply should
2222 go to the addresses indicated in that field and not to
2223 the address(es) indicated in the "From" field.
2225 So we check a Sender field if there is one, else a Reply_to field, else a From
2226 field. As some strange messages may have more than one of these fields,
2227 especially if they are resent- fields, check all of them if there is more than
2231 user_msgptr points to where to put a user error message
2232 log_msgptr points to where to put a log error message
2233 callout timeout for callout check (passed to verify_address())
2234 callout_overall overall callout timeout (ditto)
2235 callout_connect connect callout timeout (ditto)
2236 se_mailfrom mailfrom for verify; NULL => ""
2237 pm_mailfrom sender for pm callout check (passed to verify_address())
2238 options callout options (passed to verify_address())
2239 verrno where to put the address basic_errno
2241 If log_msgptr is set to something without setting user_msgptr, the caller
2242 normally uses log_msgptr for both things.
2244 Returns: result of the verification attempt: OK, FAIL, or DEFER;
2245 FAIL is given if no appropriate headers are found
2249 verify_check_header_address(uschar
**user_msgptr
, uschar
**log_msgptr
,
2250 int callout
, int callout_overall
, int callout_connect
, uschar
*se_mailfrom
,
2251 uschar
*pm_mailfrom
, int options
, int *verrno
)
2253 static int header_types
[] = { htype_sender
, htype_reply_to
, htype_from
};
2258 for (i
= 0; i
< 3 && !done
; i
++)
2261 for (h
= header_list
; h
!= NULL
&& !done
; h
= h
->next
)
2263 int terminator
, new_ok
;
2264 uschar
*s
, *ss
, *endname
;
2266 if (h
->type
!= header_types
[i
]) continue;
2267 s
= endname
= Ustrchr(h
->text
, ':') + 1;
2269 /* Scan the addresses in the header, enabling group syntax. Note that we
2270 have to reset this after the header has been scanned. */
2272 parse_allow_group
= TRUE
;
2276 address_item
*vaddr
;
2278 while (isspace(*s
) || *s
== ',') s
++;
2279 if (*s
== 0) break; /* End of header */
2281 ss
= parse_find_address_end(s
, FALSE
);
2283 /* The terminator is a comma or end of header, but there may be white
2284 space preceding it (including newline for the last address). Move back
2285 past any white space so we can check against any cached envelope sender
2286 address verifications. */
2288 while (isspace(ss
[-1])) ss
--;
2292 HDEBUG(D_verify
) debug_printf("verifying %.*s header address %s\n",
2293 (int)(endname
- h
->text
), h
->text
, s
);
2295 /* See if we have already verified this address as an envelope sender,
2296 and if so, use the previous answer. */
2298 vaddr
= verify_checked_sender(s
);
2300 if (vaddr
!= NULL
&& /* Previously checked */
2301 (callout
<= 0 || /* No callout needed; OR */
2302 vaddr
->special_action
> 256)) /* Callout was done */
2304 new_ok
= vaddr
->special_action
& 255;
2305 HDEBUG(D_verify
) debug_printf("previously checked as envelope sender\n");
2306 *ss
= terminator
; /* Restore shortened string */
2309 /* Otherwise we run the verification now. We must restore the shortened
2310 string before running the verification, so the headers are correct, in
2311 case there is any rewriting. */
2315 int start
, end
, domain
;
2316 uschar
*address
= parse_extract_address(s
, log_msgptr
, &start
, &end
,
2321 /* If we found an empty address, just carry on with the next one, but
2322 kill the message. */
2324 if (address
== NULL
&& Ustrcmp(*log_msgptr
, "empty address") == 0)
2331 /* If verification failed because of a syntax error, fail this
2332 function, and ensure that the failing address gets added to the error
2335 if (address
== NULL
)
2338 while (ss
> s
&& isspace(ss
[-1])) ss
--;
2339 *log_msgptr
= string_sprintf("syntax error in '%.*s' header when "
2340 "scanning for sender: %s in \"%.*s\"",
2341 endname
- h
->text
, h
->text
, *log_msgptr
, ss
- s
, s
);
2347 /* Else go ahead with the sender verification. But it isn't *the*
2348 sender of the message, so set vopt_fake_sender to stop sender_address
2349 being replaced after rewriting or qualification. */
2353 vaddr
= deliver_make_addr(address
, FALSE
);
2354 new_ok
= verify_address(vaddr
, NULL
, options
| vopt_fake_sender
,
2355 callout
, callout_overall
, callout_connect
, se_mailfrom
,
2360 /* We now have the result, either newly found, or cached. If we are
2361 giving out error details, set a specific user error. This means that the
2362 last of these will be returned to the user if all three fail. We do not
2363 set a log message - the generic one below will be used. */
2367 *verrno
= vaddr
->basic_errno
;
2368 if (smtp_return_error_details
)
2370 *user_msgptr
= string_sprintf("Rejected after DATA: "
2371 "could not verify \"%.*s\" header address\n%s: %s",
2372 endname
- h
->text
, h
->text
, vaddr
->address
, vaddr
->message
);
2376 /* Success or defer */
2385 if (new_ok
== DEFER
) yield
= DEFER
;
2387 /* Move on to any more addresses in the header */
2390 } /* Next address */
2392 parse_allow_group
= FALSE
;
2393 parse_found_group
= FALSE
;
2394 } /* Next header, unless done */
2395 } /* Next header type unless done */
2397 if (yield
== FAIL
&& *log_msgptr
== NULL
)
2398 *log_msgptr
= US
"there is no valid sender in any header line";
2400 if (yield
== DEFER
&& *log_msgptr
== NULL
)
2401 *log_msgptr
= US
"all attempts to verify a sender in a header line deferred";
2409 /*************************************************
2410 * Get RFC 1413 identification *
2411 *************************************************/
2413 /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
2414 the timeout is set to zero, then the query is not done. There may also be lists
2415 of hosts and nets which are exempt. To guard against malefactors sending
2416 non-printing characters which could, for example, disrupt a message's headers,
2417 make sure the string consists of printing characters only.
2420 port the port to connect to; usually this is IDENT_PORT (113), but when
2421 running in the test harness with -bh a different value is used.
2425 Side effect: any received ident value is put in sender_ident (NULL otherwise)
2429 verify_get_ident(int port
)
2431 int sock
, host_af
, qlen
;
2432 int received_sender_port
, received_interface_port
, n
;
2434 uschar buffer
[2048];
2436 /* Default is no ident. Check whether we want to do an ident check for this
2439 sender_ident
= NULL
;
2440 if (rfc1413_query_timeout
<= 0 || verify_check_host(&rfc1413_hosts
) != OK
)
2443 DEBUG(D_ident
) debug_printf("doing ident callback\n");
2445 /* Set up a connection to the ident port of the remote host. Bind the local end
2446 to the incoming interface address. If the sender host address is an IPv6
2447 address, the incoming interface address will also be IPv6. */
2449 host_af
= (Ustrchr(sender_host_address
, ':') == NULL
)? AF_INET
: AF_INET6
;
2450 sock
= ip_socket(SOCK_STREAM
, host_af
);
2451 if (sock
< 0) return;
2453 if (ip_bind(sock
, host_af
, interface_address
, 0) < 0)
2455 DEBUG(D_ident
) debug_printf("bind socket for ident failed: %s\n",
2460 if (ip_connect(sock
, host_af
, sender_host_address
, port
, rfc1413_query_timeout
)
2463 if (errno
== ETIMEDOUT
&& (log_extra_selector
& LX_ident_timeout
) != 0)
2465 log_write(0, LOG_MAIN
, "ident connection to %s timed out",
2466 sender_host_address
);
2470 DEBUG(D_ident
) debug_printf("ident connection to %s failed: %s\n",
2471 sender_host_address
, strerror(errno
));
2476 /* Construct and send the query. */
2478 sprintf(CS buffer
, "%d , %d\r\n", sender_host_port
, interface_port
);
2479 qlen
= Ustrlen(buffer
);
2480 if (send(sock
, buffer
, qlen
, 0) < 0)
2482 DEBUG(D_ident
) debug_printf("ident send failed: %s\n", strerror(errno
));
2486 /* Read a response line. We put it into the rest of the buffer, using several
2487 recv() calls if necessary. */
2495 int size
= sizeof(buffer
) - (p
- buffer
);
2497 if (size
<= 0) goto END_OFF
; /* Buffer filled without seeing \n. */
2498 count
= ip_recv(sock
, p
, size
, rfc1413_query_timeout
);
2499 if (count
<= 0) goto END_OFF
; /* Read error or EOF */
2501 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
2502 generous, and accept a plain \n terminator as well. The only illegal
2505 for (pp
= p
; pp
< p
+ count
; pp
++)
2507 if (*pp
== 0) goto END_OFF
; /* Zero octet not allowed */
2510 if (pp
[-1] == '\r') pp
--;
2512 goto GOT_DATA
; /* Break out of both loops */
2516 /* Reached the end of the data without finding \n. Let the loop continue to
2517 read some more, if there is room. */
2524 /* We have received a line of data. Check it carefully. It must start with the
2525 same two port numbers that we sent, followed by data as defined by the RFC. For
2528 12345 , 25 : USERID : UNIX :root
2530 However, the amount of white space may be different to what we sent. In the
2531 "osname" field there may be several sub-fields, comma separated. The data we
2532 actually want to save follows the third colon. Some systems put leading spaces
2533 in it - we discard those. */
2535 if (sscanf(CS buffer
+ qlen
, "%d , %d%n", &received_sender_port
,
2536 &received_interface_port
, &n
) != 2 ||
2537 received_sender_port
!= sender_host_port
||
2538 received_interface_port
!= interface_port
)
2541 p
= buffer
+ qlen
+ n
;
2542 while(isspace(*p
)) p
++;
2543 if (*p
++ != ':') goto END_OFF
;
2544 while(isspace(*p
)) p
++;
2545 if (Ustrncmp(p
, "USERID", 6) != 0) goto END_OFF
;
2547 while(isspace(*p
)) p
++;
2548 if (*p
++ != ':') goto END_OFF
;
2549 while (*p
!= 0 && *p
!= ':') p
++;
2550 if (*p
++ == 0) goto END_OFF
;
2551 while(isspace(*p
)) p
++;
2552 if (*p
== 0) goto END_OFF
;
2554 /* The rest of the line is the data we want. We turn it into printing
2555 characters when we save it, so that it cannot mess up the format of any logging
2556 or Received: lines into which it gets inserted. We keep a maximum of 127
2559 sender_ident
= string_printing(string_copyn(p
, 127));
2560 DEBUG(D_ident
) debug_printf("sender_ident = %s\n", sender_ident
);
2570 /*************************************************
2571 * Match host to a single host-list item *
2572 *************************************************/
2574 /* This function compares a host (name or address) against a single item
2575 from a host list. The host name gets looked up if it is needed and is not
2576 already known. The function is called from verify_check_this_host() via
2577 match_check_list(), which is why most of its arguments are in a single block.
2580 arg the argument block (see below)
2581 ss the host-list item
2582 valueptr where to pass back looked up data, or NULL
2583 error for error message when returning ERROR
2586 host_name (a) the host name, or
2587 (b) NULL, implying use sender_host_name and
2588 sender_host_aliases, looking them up if required, or
2589 (c) the empty string, meaning that only IP address matches
2591 host_address the host address
2592 host_ipv4 the IPv4 address taken from an IPv6 one
2596 DEFER lookup deferred
2597 ERROR (a) failed to find the host name or IP address, or
2598 (b) unknown lookup type specified, or
2599 (c) host name encountered when only IP addresses are
2604 check_host(void *arg
, uschar
*ss
, uschar
**valueptr
, uschar
**error
)
2606 check_host_block
*cb
= (check_host_block
*)arg
;
2609 BOOL iplookup
= FALSE
;
2610 BOOL isquery
= FALSE
;
2611 BOOL isiponly
= cb
->host_name
!= NULL
&& cb
->host_name
[0] == 0;
2616 /* Optimize for the special case when the pattern is "*". */
2618 if (*ss
== '*' && ss
[1] == 0) return OK
;
2620 /* If the pattern is empty, it matches only in the case when there is no host -
2621 this can occur in ACL checking for SMTP input using the -bs option. In this
2622 situation, the host address is the empty string. */
2624 if (cb
->host_address
[0] == 0) return (*ss
== 0)? OK
: FAIL
;
2625 if (*ss
== 0) return FAIL
;
2627 /* If the pattern is precisely "@" then match against the primary host name,
2628 provided that host name matching is permitted; if it's "@[]" match against the
2629 local host's IP addresses. */
2635 if (isiponly
) return ERROR
;
2636 ss
= primary_hostname
;
2638 else if (Ustrcmp(ss
, "@[]") == 0)
2640 ip_address_item
*ip
;
2641 for (ip
= host_find_interfaces(); ip
!= NULL
; ip
= ip
->next
)
2642 if (Ustrcmp(ip
->address
, cb
->host_address
) == 0) return OK
;
2647 /* If the pattern is an IP address, optionally followed by a bitmask count, do
2648 a (possibly masked) comparision with the current IP address. */
2650 if (string_is_ip_address(ss
, &maskoffset
) != 0)
2651 return (host_is_in_net(cb
->host_address
, ss
, maskoffset
)? OK
: FAIL
);
2653 /* The pattern is not an IP address. A common error that people make is to omit
2654 one component of an IPv4 address, either by accident, or believing that, for
2655 example, 1.2.3/24 is the same as 1.2.3.0/24, or 1.2.3 is the same as 1.2.3.0,
2656 which it isn't. (Those applications that do accept 1.2.3 as an IP address
2657 interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
2658 ancient specification.) To aid in debugging these cases, we give a specific
2659 error if the pattern contains only digits and dots or contains a slash preceded
2660 only by digits and dots (a slash at the start indicates a file name and of
2661 course slashes may be present in lookups, but not preceded only by digits and
2664 for (t
= ss
; isdigit(*t
) || *t
== '.'; t
++);
2665 if (*t
== 0 || (*t
== '/' && t
!= ss
))
2667 *error
= US
"malformed IPv4 address or address mask";
2671 /* See if there is a semicolon in the pattern */
2673 semicolon
= Ustrchr(ss
, ';');
2675 /* If we are doing an IP address only match, then all lookups must be IP
2676 address lookups, even if there is no "net-". */
2680 iplookup
= semicolon
!= NULL
;
2683 /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
2684 a lookup on a masked IP network, in textual form. We obey this code even if we
2685 have already set iplookup, so as to skip over the "net-" prefix and to set the
2686 mask length. The net- stuff really only applies to single-key lookups where the
2687 key is implicit. For query-style lookups the key is specified in the query.
2688 From release 4.30, the use of net- for query style is no longer needed, but we
2689 retain it for backward compatibility. */
2691 if (Ustrncmp(ss
, "net", 3) == 0 && semicolon
!= NULL
)
2694 for (t
= ss
+ 3; isdigit(*t
); t
++) mlen
= mlen
* 10 + *t
- '0';
2695 if (mlen
== 0 && t
== ss
+3) mlen
= -1; /* No mask supplied */
2696 iplookup
= (*t
++ == '-');
2700 /* Do the IP address lookup if that is indeed what we have */
2708 uschar
*filename
, *key
, *result
;
2711 /* Find the search type */
2713 search_type
= search_findtype(t
, semicolon
- t
);
2715 if (search_type
< 0) log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "%s",
2716 search_error_message
);
2718 /* Adjust parameters for the type of lookup. For a query-style lookup, there
2719 is no file name, and the "key" is just the query. For query-style with a file
2720 name, we have to fish the file off the start of the query. For a single-key
2721 lookup, the key is the current IP address, masked appropriately, and
2722 reconverted to text form, with the mask appended. For IPv6 addresses, specify
2723 dot separators instead of colons, except when the lookup type is "iplsearch".
2726 if (mac_islookup(search_type
, lookup_absfilequery
))
2728 filename
= semicolon
+ 1;
2730 while (*key
!= 0 && !isspace(*key
)) key
++;
2731 filename
= string_copyn(filename
, key
- filename
);
2732 while (isspace(*key
)) key
++;
2734 else if (mac_islookup(search_type
, lookup_querystyle
))
2737 key
= semicolon
+ 1;
2739 else /* Single-key style */
2741 int sep
= (Ustrcmp(lookup_list
[search_type
]->name
, "iplsearch") == 0)?
2743 insize
= host_aton(cb
->host_address
, incoming
);
2744 host_mask(insize
, incoming
, mlen
);
2745 (void)host_nmtoa(insize
, incoming
, mlen
, buffer
, sep
);
2747 filename
= semicolon
+ 1;
2750 /* Now do the actual lookup; note that there is no search_close() because
2751 of the caching arrangements. */
2753 handle
= search_open(filename
, search_type
, 0, NULL
, NULL
);
2754 if (handle
== NULL
) log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "%s",
2755 search_error_message
);
2756 result
= search_find(handle
, filename
, key
, -1, NULL
, 0, 0, NULL
);
2757 if (valueptr
!= NULL
) *valueptr
= result
;
2758 return (result
!= NULL
)? OK
: search_find_defer
? DEFER
: FAIL
;
2761 /* The pattern is not an IP address or network reference of any kind. That is,
2762 it is a host name pattern. If this is an IP only match, there's an error in the
2767 *error
= US
"cannot match host name in match_ip list";
2771 /* Check the characters of the pattern to see if they comprise only letters,
2772 digits, full stops, and hyphens (the constituents of domain names). Allow
2773 underscores, as they are all too commonly found. Sigh. Also, if
2774 allow_utf8_domains is set, allow top-bit characters. */
2776 for (t
= ss
; *t
!= 0; t
++)
2777 if (!isalnum(*t
) && *t
!= '.' && *t
!= '-' && *t
!= '_' &&
2778 (!allow_utf8_domains
|| *t
< 128)) break;
2780 /* If the pattern is a complete domain name, with no fancy characters, look up
2781 its IP address and match against that. Note that a multi-homed host will add
2782 items to the chain. */
2793 rc
= host_find_byname(&h
, NULL
, HOST_FIND_QUALIFY_SINGLE
, NULL
, FALSE
);
2794 if (rc
== HOST_FOUND
|| rc
== HOST_FOUND_LOCAL
)
2797 for (hh
= &h
; hh
!= NULL
; hh
= hh
->next
)
2799 if (host_is_in_net(hh
->address
, cb
->host_address
, 0)) return OK
;
2803 if (rc
== HOST_FIND_AGAIN
) return DEFER
;
2804 *error
= string_sprintf("failed to find IP address for %s", ss
);
2808 /* Almost all subsequent comparisons require the host name, and can be done
2809 using the general string matching function. When this function is called for
2810 outgoing hosts, the name is always given explicitly. If it is NULL, it means we
2811 must use sender_host_name and its aliases, looking them up if necessary. */
2813 if (cb
->host_name
!= NULL
) /* Explicit host name given */
2814 return match_check_string(cb
->host_name
, ss
, -1, TRUE
, TRUE
, TRUE
,
2817 /* Host name not given; in principle we need the sender host name and its
2818 aliases. However, for query-style lookups, we do not need the name if the
2819 query does not contain $sender_host_name. From release 4.23, a reference to
2820 $sender_host_name causes it to be looked up, so we don't need to do the lookup
2823 if ((semicolon
= Ustrchr(ss
, ';')) != NULL
)
2826 int partial
, affixlen
, starflags
, id
;
2829 id
= search_findtype_partial(ss
, &partial
, &affix
, &affixlen
, &starflags
);
2832 if (id
< 0) /* Unknown lookup type */
2834 log_write(0, LOG_MAIN
|LOG_PANIC
, "%s in host list item \"%s\"",
2835 search_error_message
, ss
);
2838 isquery
= mac_islookup(id
, lookup_querystyle
|lookup_absfilequery
);
2843 switch(match_check_string(US
"", ss
, -1, TRUE
, TRUE
, TRUE
, valueptr
))
2846 case DEFER
: return DEFER
;
2847 default: return FAIL
;
2851 /* Not a query-style lookup; must ensure the host name is present, and then we
2852 do a check on the name and all its aliases. */
2854 if (sender_host_name
== NULL
)
2856 HDEBUG(D_host_lookup
)
2857 debug_printf("sender host name required, to match against %s\n", ss
);
2858 if (host_lookup_failed
|| host_name_lookup() != OK
)
2860 *error
= string_sprintf("failed to find host name for %s",
2861 sender_host_address
);;
2864 host_build_sender_fullhost();
2867 /* Match on the sender host name, using the general matching function */
2869 switch(match_check_string(sender_host_name
, ss
, -1, TRUE
, TRUE
, TRUE
,
2873 case DEFER
: return DEFER
;
2876 /* If there are aliases, try matching on them. */
2878 aliases
= sender_host_aliases
;
2879 while (*aliases
!= NULL
)
2881 switch(match_check_string(*aliases
++, ss
, -1, TRUE
, TRUE
, TRUE
, valueptr
))
2884 case DEFER
: return DEFER
;
2893 /*************************************************
2894 * Check a specific host matches a host list *
2895 *************************************************/
2897 /* This function is passed a host list containing items in a number of
2898 different formats and the identity of a host. Its job is to determine whether
2899 the given host is in the set of hosts defined by the list. The host name is
2900 passed as a pointer so that it can be looked up if needed and not already
2901 known. This is commonly the case when called from verify_check_host() to check
2902 an incoming connection. When called from elsewhere the host name should usually
2905 This function is now just a front end to match_check_list(), which runs common
2906 code for scanning a list. We pass it the check_host() function to perform a
2910 listptr pointer to the host list
2911 cache_bits pointer to cache for named lists, or NULL
2912 host_name the host name or NULL, implying use sender_host_name and
2913 sender_host_aliases, looking them up if required
2914 host_address the IP address
2915 valueptr if not NULL, data from a lookup is passed back here
2917 Returns: OK if the host is in the defined set
2918 FAIL if the host is not in the defined set,
2919 DEFER if a data lookup deferred (not a host lookup)
2921 If the host name was needed in order to make a comparison, and could not be
2922 determined from the IP address, the result is FAIL unless the item
2923 "+allow_unknown" was met earlier in the list, in which case OK is returned. */
2926 verify_check_this_host(uschar
**listptr
, unsigned int *cache_bits
,
2927 uschar
*host_name
, uschar
*host_address
, uschar
**valueptr
)
2930 unsigned int *local_cache_bits
= cache_bits
;
2931 uschar
*save_host_address
= deliver_host_address
;
2932 check_host_block cb
;
2933 cb
.host_name
= host_name
;
2934 cb
.host_address
= host_address
;
2936 if (valueptr
!= NULL
) *valueptr
= NULL
;
2938 /* If the host address starts off ::ffff: it is an IPv6 address in
2939 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2942 cb
.host_ipv4
= (Ustrncmp(host_address
, "::ffff:", 7) == 0)?
2943 host_address
+ 7 : host_address
;
2945 /* During the running of the check, put the IP address into $host_address. In
2946 the case of calls from the smtp transport, it will already be there. However,
2947 in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
2948 the safe side, any existing setting is preserved, though as I write this
2949 (November 2004) I can't see any cases where it is actually needed. */
2951 deliver_host_address
= host_address
;
2952 rc
= match_check_list(
2953 listptr
, /* the list */
2954 0, /* separator character */
2955 &hostlist_anchor
, /* anchor pointer */
2956 &local_cache_bits
, /* cache pointer */
2957 check_host
, /* function for testing */
2958 &cb
, /* argument for function */
2959 MCL_HOST
, /* type of check */
2960 (host_address
== sender_host_address
)?
2961 US
"host" : host_address
, /* text for debugging */
2962 valueptr
); /* where to pass back data */
2963 deliver_host_address
= save_host_address
;
2970 /*************************************************
2971 * Check the remote host matches a list *
2972 *************************************************/
2974 /* This is a front end to verify_check_this_host(), created because checking
2975 the remote host is a common occurrence. With luck, a good compiler will spot
2976 the tail recursion and optimize it. If there's no host address, this is
2977 command-line SMTP input - check against an empty string for the address.
2980 listptr pointer to the host list
2982 Returns: the yield of verify_check_this_host(),
2983 i.e. OK, FAIL, or DEFER
2987 verify_check_host(uschar
**listptr
)
2989 return verify_check_this_host(listptr
, sender_host_cache
, NULL
,
2990 (sender_host_address
== NULL
)? US
"" : sender_host_address
, NULL
);
2997 /*************************************************
2998 * Invert an IP address *
2999 *************************************************/
3001 /* Originally just used for DNS xBL lists, now also used for the
3002 reverse_ip expansion operator.
3005 buffer where to put the answer
3006 address the address to invert
3010 invert_address(uschar
*buffer
, uschar
*address
)
3013 uschar
*bptr
= buffer
;
3015 /* If this is an IPv4 address mapped into IPv6 format, adjust the pointer
3016 to the IPv4 part only. */
3018 if (Ustrncmp(address
, "::ffff:", 7) == 0) address
+= 7;
3020 /* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is
3023 if (host_aton(address
, bin
) == 1)
3027 for (i
= 0; i
< 4; i
++)
3029 sprintf(CS bptr
, "%d.", x
& 255);
3030 while (*bptr
) bptr
++;
3035 /* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses
3036 in any DNS black lists, and the format in which they will be looked up is
3037 unknown. This is just a guess. */
3043 for (j
= 3; j
>= 0; j
--)
3046 for (i
= 0; i
< 8; i
++)
3048 sprintf(CS bptr
, "%x.", x
& 15);
3049 while (*bptr
) bptr
++;
3056 /* Remove trailing period -- this is needed so that both arbitrary
3057 dnsbl keydomains and inverted addresses may be combined with the
3058 same format string, "%s.%s" */
3065 /*************************************************
3066 * Perform a single dnsbl lookup *
3067 *************************************************/
3069 /* This function is called from verify_check_dnsbl() below. It is also called
3070 recursively from within itself when domain and domain_txt are different
3071 pointers, in order to get the TXT record from the alternate domain.
3074 domain the outer dnsbl domain
3075 domain_txt alternate domain to lookup TXT record on success; when the
3076 same domain is to be used, domain_txt == domain (that is,
3077 the pointers must be identical, not just the text)
3078 keydomain the current keydomain (for debug message)
3079 prepend subdomain to lookup (like keydomain, but
3080 reversed if IP address)
3081 iplist the list of matching IP addresses, or NULL for "any"
3082 bitmask true if bitmask matching is wanted
3083 match_type condition for 'succeed' result
3084 0 => Any RR in iplist (=)
3085 1 => No RR in iplist (!=)
3086 2 => All RRs in iplist (==)
3087 3 => Some RRs not in iplist (!==)
3088 the two bits are defined as MT_NOT and MT_ALL
3089 defer_return what to return for a defer
3091 Returns: OK if lookup succeeded
3096 one_check_dnsbl(uschar
*domain
, uschar
*domain_txt
, uschar
*keydomain
,
3097 uschar
*prepend
, uschar
*iplist
, BOOL bitmask
, int match_type
,
3103 dnsbl_cache_block
*cb
;
3104 int old_pool
= store_pool
;
3105 uschar query
[256]; /* DNS domain max length */
3107 /* Construct the specific query domainname */
3109 if (!string_format(query
, sizeof(query
), "%s.%s", prepend
, domain
))
3111 log_write(0, LOG_MAIN
|LOG_PANIC
, "dnslist query is too long "
3112 "(ignored): %s...", query
);
3116 /* Look for this query in the cache. */
3118 t
= tree_search(dnsbl_cache
, query
);
3120 /* If not cached from a previous lookup, we must do a DNS lookup, and
3121 cache the result in permanent memory. */
3125 store_pool
= POOL_PERM
;
3127 /* Set up a tree entry to cache the lookup */
3129 t
= store_get(sizeof(tree_node
) + Ustrlen(query
));
3130 Ustrcpy(t
->name
, query
);
3131 t
->data
.ptr
= cb
= store_get(sizeof(dnsbl_cache_block
));
3132 (void)tree_insertnode(&dnsbl_cache
, t
);
3134 /* Do the DNS loopup . */
3136 HDEBUG(D_dnsbl
) debug_printf("new DNS lookup for %s\n", query
);
3137 cb
->rc
= dns_basic_lookup(&dnsa
, query
, T_A
);
3138 cb
->text_set
= FALSE
;
3142 /* If the lookup succeeded, cache the RHS address. The code allows for
3143 more than one address - this was for complete generality and the possible
3144 use of A6 records. However, A6 records have been reduced to experimental
3145 status (August 2001) and may die out. So they may never get used at all,
3146 let alone in dnsbl records. However, leave the code here, just in case.
3148 Quite apart from one A6 RR generating multiple addresses, there are DNS
3149 lists that return more than one A record, so we must handle multiple
3150 addresses generated in that way as well. */
3152 if (cb
->rc
== DNS_SUCCEED
)
3155 dns_address
**addrp
= &(cb
->rhs
);
3156 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
3158 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
3160 if (rr
->type
== T_A
)
3162 dns_address
*da
= dns_address_from_rr(&dnsa
, rr
);
3166 while (da
->next
!= NULL
) da
= da
->next
;
3167 addrp
= &(da
->next
);
3172 /* If we didn't find any A records, change the return code. This can
3173 happen when there is a CNAME record but there are no A records for what
3176 if (cb
->rhs
== NULL
) cb
->rc
= DNS_NODATA
;
3179 store_pool
= old_pool
;
3182 /* Previous lookup was cached */
3186 HDEBUG(D_dnsbl
) debug_printf("using result of previous DNS lookup\n");
3190 /* We now have the result of the DNS lookup, either newly done, or cached
3191 from a previous call. If the lookup succeeded, check against the address
3192 list if there is one. This may be a positive equality list (introduced by
3193 "="), a negative equality list (introduced by "!="), a positive bitmask
3194 list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/
3196 if (cb
->rc
== DNS_SUCCEED
)
3198 dns_address
*da
= NULL
;
3199 uschar
*addlist
= cb
->rhs
->address
;
3201 /* For A and AAAA records, there may be multiple addresses from multiple
3202 records. For A6 records (currently not expected to be used) there may be
3203 multiple addresses from a single record. */
3205 for (da
= cb
->rhs
->next
; da
!= NULL
; da
= da
->next
)
3206 addlist
= string_sprintf("%s, %s", addlist
, da
->address
);
3208 HDEBUG(D_dnsbl
) debug_printf("DNS lookup for %s succeeded (yielding %s)\n",
3211 /* Address list check; this can be either for equality, or via a bitmask.
3212 In the latter case, all the bits must match. */
3216 for (da
= cb
->rhs
; da
!= NULL
; da
= da
->next
)
3220 uschar
*ptr
= iplist
;
3223 /* Handle exact matching */
3227 while ((res
= string_nextinlist(&ptr
, &ipsep
, ip
, sizeof(ip
))) != NULL
)
3229 if (Ustrcmp(CS da
->address
, ip
) == 0) break;
3233 /* Handle bitmask matching */
3240 /* At present, all known DNS blocking lists use A records, with
3241 IPv4 addresses on the RHS encoding the information they return. I
3242 wonder if this will linger on as the last vestige of IPv4 when IPv6
3243 is ubiquitous? Anyway, for now we use paranoia code to completely
3244 ignore IPv6 addresses. The default mask is 0, which always matches.
3245 We change this only for IPv4 addresses in the list. */
3247 if (host_aton(da
->address
, address
) == 1) mask
= address
[0];
3249 /* Scan the returned addresses, skipping any that are IPv6 */
3251 while ((res
= string_nextinlist(&ptr
, &ipsep
, ip
, sizeof(ip
))) != NULL
)
3253 if (host_aton(ip
, address
) != 1) continue;
3254 if ((address
[0] & mask
) == address
[0]) break;
3260 (a) An IP address in an any ('=') list matched, or
3261 (b) No IP address in an all ('==') list matched
3263 then we're done searching. */
3265 if (((match_type
& MT_ALL
) != 0) == (res
== NULL
)) break;
3268 /* If da == NULL, either
3270 (a) No IP address in an any ('=') list matched, or
3271 (b) An IP address in an all ('==') list didn't match
3273 so behave as if the DNSBL lookup had not succeeded, i.e. the host is not on
3276 if ((match_type
== MT_NOT
|| match_type
== MT_ALL
) != (da
== NULL
))
3284 res
= US
"was no match";
3287 res
= US
"was an exclude match";
3290 res
= US
"was an IP address that did not match";
3293 res
= US
"were no IP addresses that did not match";
3296 debug_printf("=> but we are not accepting this block class because\n");
3297 debug_printf("=> there %s for %s%c%s\n",
3299 ((match_type
& MT_ALL
) == 0)? "" : "=",
3300 bitmask
? '&' : '=', iplist
);
3306 /* Either there was no IP list, or the record matched, implying that the
3307 domain is on the list. We now want to find a corresponding TXT record. If an
3308 alternate domain is specified for the TXT record, call this function
3309 recursively to look that up; this has the side effect of re-checking that
3310 there is indeed an A record at the alternate domain. */
3312 if (domain_txt
!= domain
)
3313 return one_check_dnsbl(domain_txt
, domain_txt
, keydomain
, prepend
, NULL
,
3314 FALSE
, match_type
, defer_return
);
3316 /* If there is no alternate domain, look up a TXT record in the main domain
3317 if it has not previously been cached. */
3321 cb
->text_set
= TRUE
;
3322 if (dns_basic_lookup(&dnsa
, query
, T_TXT
) == DNS_SUCCEED
)
3325 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
3327 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
3328 if (rr
->type
== T_TXT
) break;
3331 int len
= (rr
->data
)[0];
3332 if (len
> 511) len
= 127;
3333 store_pool
= POOL_PERM
;
3334 cb
->text
= string_sprintf("%.*s", len
, (const uschar
*)(rr
->data
+1));
3335 store_pool
= old_pool
;
3340 dnslist_value
= addlist
;
3341 dnslist_text
= cb
->text
;
3345 /* There was a problem with the DNS lookup */
3347 if (cb
->rc
!= DNS_NOMATCH
&& cb
->rc
!= DNS_NODATA
)
3349 log_write(L_dnslist_defer
, LOG_MAIN
,
3350 "DNS list lookup defer (probably timeout) for %s: %s", query
,
3351 (defer_return
== OK
)? US
"assumed in list" :
3352 (defer_return
== FAIL
)? US
"assumed not in list" :
3353 US
"returned DEFER");
3354 return defer_return
;
3357 /* No entry was found in the DNS; continue for next domain */
3361 debug_printf("DNS lookup for %s failed\n", query
);
3362 debug_printf("=> that means %s is not listed at %s\n",
3372 /*************************************************
3373 * Check host against DNS black lists *
3374 *************************************************/
3376 /* This function runs checks against a list of DNS black lists, until one
3377 matches. Each item on the list can be of the form
3379 domain=ip-address/key
3381 The domain is the right-most domain that is used for the query, for example,
3382 blackholes.mail-abuse.org. If the IP address is present, there is a match only
3383 if the DNS lookup returns a matching IP address. Several addresses may be
3384 given, comma-separated, for example: x.y.z=127.0.0.1,127.0.0.2.
3386 If no key is given, what is looked up in the domain is the inverted IP address
3387 of the current client host. If a key is given, it is used to construct the
3388 domain for the lookup. For example:
3390 dsn.rfc-ignorant.org/$sender_address_domain
3392 After finding a match in the DNS, the domain is placed in $dnslist_domain, and
3393 then we check for a TXT record for an error message, and if found, save its
3394 value in $dnslist_text. We also cache everything in a tree, to optimize
3397 The TXT record is normally looked up in the same domain as the A record, but
3398 when many lists are combined in a single DNS domain, this will not be a very
3399 specific message. It is possible to specify a different domain for looking up
3400 TXT records; this is given before the main domain, comma-separated. For
3403 dnslists = http.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.2 : \
3404 socks.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.3
3406 The caching ensures that only one lookup in dnsbl.sorbs.net is done.
3408 Note: an address for testing RBL is 192.203.178.39
3409 Note: an address for testing DUL is 192.203.178.4
3410 Note: a domain for testing RFCI is example.tld.dsn.rfc-ignorant.org
3413 listptr the domain/address/data list
3415 Returns: OK successful lookup (i.e. the address is on the list), or
3416 lookup deferred after +include_unknown
3417 FAIL name not found, or no data found for the given type, or
3418 lookup deferred after +exclude_unknown (default)
3419 DEFER lookup failure, if +defer_unknown was set
3423 verify_check_dnsbl(uschar
**listptr
)
3426 int defer_return
= FAIL
;
3427 uschar
*list
= *listptr
;
3430 uschar buffer
[1024];
3431 uschar revadd
[128]; /* Long enough for IPv6 address */
3433 /* Indicate that the inverted IP address is not yet set up */
3437 /* In case this is the first time the DNS resolver is being used. */
3439 dns_init(FALSE
, FALSE
);
3441 /* Loop through all the domains supplied, until something matches */
3443 while ((domain
= string_nextinlist(&list
, &sep
, buffer
, sizeof(buffer
))) != NULL
)
3446 BOOL bitmask
= FALSE
;
3453 HDEBUG(D_dnsbl
) debug_printf("DNS list check: %s\n", domain
);
3455 /* Deal with special values that change the behaviour on defer */
3457 if (domain
[0] == '+')
3459 if (strcmpic(domain
, US
"+include_unknown") == 0) defer_return
= OK
;
3460 else if (strcmpic(domain
, US
"+exclude_unknown") == 0) defer_return
= FAIL
;
3461 else if (strcmpic(domain
, US
"+defer_unknown") == 0) defer_return
= DEFER
;
3463 log_write(0, LOG_MAIN
|LOG_PANIC
, "unknown item in dnslist (ignored): %s",
3468 /* See if there's explicit data to be looked up */
3470 key
= Ustrchr(domain
, '/');
3471 if (key
!= NULL
) *key
++ = 0;
3473 /* See if there's a list of addresses supplied after the domain name. This is
3474 introduced by an = or a & character; if preceded by = we require all matches
3475 and if preceded by ! we invert the result. */
3477 iplist
= Ustrchr(domain
, '=');
3481 iplist
= Ustrchr(domain
, '&');
3484 if (iplist
!= NULL
) /* Found either = or & */
3486 if (iplist
> domain
&& iplist
[-1] == '!') /* Handle preceding ! */
3488 match_type
|= MT_NOT
;
3492 *iplist
++ = 0; /* Terminate domain, move on */
3494 /* If we found = (bitmask == FALSE), check for == or =& */
3496 if (!bitmask
&& (*iplist
== '=' || *iplist
== '&'))
3498 bitmask
= *iplist
++ == '&';
3499 match_type
|= MT_ALL
;
3503 /* If there is a comma in the domain, it indicates that a second domain for
3504 looking up TXT records is provided, before the main domain. Otherwise we must
3505 set domain_txt == domain. */
3507 domain_txt
= domain
;
3508 comma
= Ustrchr(domain
, ',');
3515 /* Check that what we have left is a sensible domain name. There is no reason
3516 why these domains should in fact use the same syntax as hosts and email
3517 domains, but in practice they seem to. However, there is little point in
3518 actually causing an error here, because that would no doubt hold up incoming
3519 mail. Instead, I'll just log it. */
3521 for (s
= domain
; *s
!= 0; s
++)
3523 if (!isalnum(*s
) && *s
!= '-' && *s
!= '.' && *s
!= '_')
3525 log_write(0, LOG_MAIN
, "dnslists domain \"%s\" contains "
3526 "strange characters - is this right?", domain
);
3531 /* Check the alternate domain if present */
3533 if (domain_txt
!= domain
) for (s
= domain_txt
; *s
!= 0; s
++)
3535 if (!isalnum(*s
) && *s
!= '-' && *s
!= '.' && *s
!= '_')
3537 log_write(0, LOG_MAIN
, "dnslists domain \"%s\" contains "
3538 "strange characters - is this right?", domain_txt
);
3543 /* If there is no key string, construct the query by adding the domain name
3544 onto the inverted host address, and perform a single DNS lookup. */
3548 if (sender_host_address
== NULL
) return FAIL
; /* can never match */
3549 if (revadd
[0] == 0) invert_address(revadd
, sender_host_address
);
3550 rc
= one_check_dnsbl(domain
, domain_txt
, sender_host_address
, revadd
,
3551 iplist
, bitmask
, match_type
, defer_return
);
3554 dnslist_domain
= string_copy(domain_txt
);
3555 dnslist_matched
= string_copy(sender_host_address
);
3556 HDEBUG(D_dnsbl
) debug_printf("=> that means %s is listed at %s\n",
3557 sender_host_address
, dnslist_domain
);
3559 if (rc
!= FAIL
) return rc
; /* OK or DEFER */
3562 /* If there is a key string, it can be a list of domains or IP addresses to
3563 be concatenated with the main domain. */
3570 uschar keybuffer
[256];
3571 uschar keyrevadd
[128];
3573 while ((keydomain
= string_nextinlist(&key
, &keysep
, keybuffer
,
3574 sizeof(keybuffer
))) != NULL
)
3576 uschar
*prepend
= keydomain
;
3578 if (string_is_ip_address(keydomain
, NULL
) != 0)
3580 invert_address(keyrevadd
, keydomain
);
3581 prepend
= keyrevadd
;
3584 rc
= one_check_dnsbl(domain
, domain_txt
, keydomain
, prepend
, iplist
,
3585 bitmask
, match_type
, defer_return
);
3589 dnslist_domain
= string_copy(domain_txt
);
3590 dnslist_matched
= string_copy(keydomain
);
3591 HDEBUG(D_dnsbl
) debug_printf("=> that means %s is listed at %s\n",
3592 keydomain
, dnslist_domain
);
3596 /* If the lookup deferred, remember this fact. We keep trying the rest
3597 of the list to see if we get a useful result, and if we don't, we return
3598 DEFER at the end. */
3600 if (rc
== DEFER
) defer
= TRUE
;
3601 } /* continue with next keystring domain/address */
3603 if (defer
) return DEFER
;
3605 } /* continue with next dnsdb outer domain */
3610 /* End of verify.c */