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 /* Now make connections to the hosts and do real callouts. The list of hosts
411 is passed in as an argument. */
413 for (host
= host_list
; host
!= NULL
&& !done
; host
= host
->next
)
415 smtp_inblock inblock
;
416 smtp_outblock outblock
;
419 BOOL send_quit
= TRUE
;
420 uschar
*active_hostname
= smtp_active_hostname
;
424 BOOL suppress_tls
= FALSE
;
425 uschar
*interface
= NULL
; /* Outgoing interface to use; NULL => any */
426 uschar inbuffer
[4096];
427 uschar outbuffer
[1024];
428 uschar responsebuffer
[4096];
430 clearflag(addr
, af_verify_pmfail
); /* postmaster callout flag */
431 clearflag(addr
, af_verify_nsfail
); /* null sender callout flag */
433 /* Skip this host if we don't have an IP address for it. */
435 if (host
->address
== NULL
)
437 DEBUG(D_verify
) debug_printf("no IP address for host name %s: skipping\n",
442 /* Check the overall callout timeout */
444 if (time(NULL
) - callout_start_time
>= callout_overall
)
446 HDEBUG(D_verify
) debug_printf("overall timeout for callout exceeded\n");
450 /* Set IPv4 or IPv6 */
452 host_af
= (Ustrchr(host
->address
, ':') == NULL
)? AF_INET
:AF_INET6
;
454 /* Expand and interpret the interface and port strings. The latter will not
455 be used if there is a host-specific port (e.g. from a manualroute router).
456 This has to be delayed till now, because they may expand differently for
457 different hosts. If there's a failure, log it, but carry on with the
460 deliver_host
= host
->name
;
461 deliver_host_address
= host
->address
;
462 deliver_domain
= addr
->domain
;
464 if (!smtp_get_interface(tf
->interface
, host_af
, addr
, NULL
, &interface
,
466 !smtp_get_port(tf
->port
, addr
, &port
, US
"callout"))
467 log_write(0, LOG_MAIN
|LOG_PANIC
, "<%s>: %s", addr
->address
,
470 /* Set HELO string according to the protocol */
471 lmtp
= Ustrcmp(tf
->protocol
, "lmtp") == 0;
472 smtps
= Ustrcmp(tf
->protocol
, "smtps") == 0;
475 HDEBUG(D_verify
) debug_printf("interface=%s port=%d\n", interface
, port
);
477 /* Set up the buffer for reading SMTP response packets. */
479 inblock
.buffer
= inbuffer
;
480 inblock
.buffersize
= sizeof(inbuffer
);
481 inblock
.ptr
= inbuffer
;
482 inblock
.ptrend
= inbuffer
;
484 /* Set up the buffer for holding SMTP commands while pipelining */
486 outblock
.buffer
= outbuffer
;
487 outblock
.buffersize
= sizeof(outbuffer
);
488 outblock
.ptr
= outbuffer
;
489 outblock
.cmd_count
= 0;
490 outblock
.authenticating
= FALSE
;
492 /* Reset the parameters of a TLS session */
493 tls_out
.cipher
= tls_out
.peerdn
= NULL
;
495 /* Connect to the host; on failure, just loop for the next one, but we
496 set the error for the last one. Use the callout_connect timeout. */
498 tls_retry_connection
:
500 inblock
.sock
= outblock
.sock
=
501 smtp_connect(host
, host_af
, port
, interface
, callout_connect
, TRUE
, NULL
);
502 /* reconsider DSCP here */
503 if (inblock
.sock
< 0)
505 addr
->message
= string_sprintf("could not connect to %s [%s]: %s",
506 host
->name
, host
->address
, strerror(errno
));
507 deliver_host
= deliver_host_address
= NULL
;
508 deliver_domain
= save_deliver_domain
;
512 /* Expand the helo_data string to find the host name to use. */
514 if (tf
->helo_data
!= NULL
)
516 uschar
*s
= expand_string(tf
->helo_data
);
518 log_write(0, LOG_MAIN
|LOG_PANIC
, "<%s>: failed to expand transport's "
519 "helo_data value for callout: %s", addr
->address
,
520 expand_string_message
);
521 else active_hostname
= s
;
524 deliver_host
= deliver_host_address
= NULL
;
525 deliver_domain
= save_deliver_domain
;
527 /* Wait for initial response, and send HELO. The smtp_write_command()
528 function leaves its command in big_buffer. This is used in error responses.
529 Initialize it in case the connection is rejected. */
531 Ustrcpy(big_buffer
, "initial connection");
533 /* Unless ssl-on-connect, wait for the initial greeting */
537 if (!smtps
|| (smtps
&& tls_out
.active
>= 0))
539 if (!(done
= smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
), '2', callout
)))
540 goto RESPONSE_FAILED
;
542 /* Not worth checking greeting line for ESMTP support */
543 if (!(esmtp
= verify_check_this_host(&(ob
->hosts_avoid_esmtp
), NULL
,
544 host
->name
, host
->address
, NULL
) != OK
))
546 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
551 if (smtps
&& tls_out
.active
< 0) /* ssl-on-connect, first pass */
554 ob
->tls_tempfail_tryclear
= FALSE
;
556 else /* all other cases */
561 if (!(done
= smtp_write_command(&outblock
, FALSE
, "%s %s\r\n",
562 !esmtp
? "HELO" : lmtp
? "LHLO" : "EHLO", active_hostname
) >= 0))
564 if (!smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
), '2', callout
))
566 if (errno
!= 0 || responsebuffer
[0] == 0 || lmtp
|| !esmtp
|| tls_out
.active
>= 0)
569 goto RESPONSE_FAILED
;
575 goto esmtp_retry
; /* fallback to HELO */
578 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
580 if (esmtp
&& !suppress_tls
&& tls_out
.active
< 0)
582 if (regex_STARTTLS
== NULL
) regex_STARTTLS
=
583 regex_must_compile(US
"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE
, TRUE
);
585 tls_offered
= pcre_exec(regex_STARTTLS
, NULL
, CS responsebuffer
,
586 Ustrlen(responsebuffer
), 0, 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
, ob
->tls_dh_min_bits
,
641 /* TLS negotiation failed; give an error. Try in clear on a new connection,
642 if the options permit it for this host. */
645 if (rc
== DEFER
&& ob
->tls_tempfail_tryclear
&& !smtps
&&
646 verify_check_this_host(&(ob
->hosts_require_tls
), NULL
, host
->name
,
647 host
->address
, NULL
) != OK
)
649 (void)close(inblock
.sock
);
650 log_write(0, LOG_MAIN
, "TLS session failure: delivering unencrypted "
651 "to %s [%s] (not in hosts_require_tls)", host
->name
, host
->address
);
653 goto tls_retry_connection
;
655 /*save_errno = ERRNO_TLSFAILURE;*/
656 /*message = US"failure while setting up TLS session";*/
662 /* TLS session is set up. Copy info for logging. */
663 addr
->cipher
= tls_out
.cipher
;
664 addr
->peerdn
= tls_out
.peerdn
;
666 /* For SMTPS we need to wait for the initial OK response, then do HELO. */
668 goto smtps_redo_greeting
;
670 /* For STARTTLS we need to redo EHLO */
675 /* If the host is required to use a secure channel, ensure that we have one. */
676 if (tls_out
.active
< 0)
677 if (verify_check_this_host(&(ob
->hosts_require_tls
), NULL
, host
->name
,
678 host
->address
, NULL
) == OK
)
680 /*save_errno = ERRNO_TLSREQUIRED;*/
681 log_write(0, LOG_MAIN
, "a TLS session is required for %s [%s], but %s",
682 host
->name
, host
->address
,
683 tls_offered
? "an attempt to start TLS failed" : "the server did not offer TLS support");
688 #endif /*SUPPORT_TLS*/
690 done
= TRUE
; /* so far so good; have response to HELO */
692 /*XXX the EHLO response would be analyzed here for IGNOREQUOTA, SIZE, PIPELINING, AUTH */
693 /* If we haven't authenticated, but are required to, give up. */
695 /*XXX "filter command specified for this transport" ??? */
696 /* for now, transport_filter by cutthrough-delivery is not supported */
697 /* Need proper integration with the proper transport mechanism. */
704 /* Clear down of the TLS, SMTP and TCP layers on error is handled below. */
707 /* Failure to accept HELO is cached; this blocks the whole domain for all
708 senders. I/O errors and defer responses are not cached. */
712 *failure_ptr
= US
"mail"; /* At or before MAIL */
713 if (errno
== 0 && responsebuffer
[0] == '5')
715 setflag(addr
, af_verify_nsfail
);
716 new_domain_record
.result
= ccache_reject
;
720 /* Send the MAIL command */
723 smtp_write_command(&outblock
, FALSE
, "MAIL FROM:<%s>\r\n",
724 from_address
) >= 0 &&
725 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
728 /* If the host does not accept MAIL FROM:<>, arrange to cache this
729 information, but again, don't record anything for an I/O error or a defer. Do
730 not cache rejections of MAIL when a non-empty sender has been used, because
731 that blocks the whole domain for all senders. */
735 *failure_ptr
= US
"mail"; /* At or before MAIL */
736 if (errno
== 0 && responsebuffer
[0] == '5')
738 setflag(addr
, af_verify_nsfail
);
739 if (from_address
[0] == 0)
740 new_domain_record
.result
= ccache_reject_mfnull
;
744 /* Otherwise, proceed to check a "random" address (if required), then the
745 given address, and the postmaster address (if required). Between each check,
746 issue RSET, because some servers accept only one recipient after MAIL
749 Before doing this, set the result in the domain cache record to "accept",
750 unless its previous value was ccache_reject_mfnull. In that case, the domain
751 rejects MAIL FROM:<> and we want to continue to remember that. When that is
752 the case, we have got here only in the case of a recipient verification with
753 a non-null sender. */
757 new_domain_record
.result
=
758 (old_domain_cache_result
== ccache_reject_mfnull
)?
759 ccache_reject_mfnull
: ccache_accept
;
761 /* Do the random local part check first */
763 if (random_local_part
!= NULL
)
765 uschar randombuffer
[1024];
767 smtp_write_command(&outblock
, FALSE
,
768 "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part
,
769 addr
->domain
) >= 0 &&
770 smtp_read_response(&inblock
, randombuffer
,
771 sizeof(randombuffer
), '2', callout
);
773 /* Remember when we last did a random test */
775 new_domain_record
.random_stamp
= time(NULL
);
777 /* If accepted, we aren't going to do any further tests below. */
781 new_domain_record
.random_result
= ccache_accept
;
784 /* Otherwise, cache a real negative response, and get back to the right
785 state to send RCPT. Unless there's some problem such as a dropped
786 connection, we expect to succeed, because the commands succeeded above. */
790 if (randombuffer
[0] == '5')
791 new_domain_record
.random_result
= ccache_reject
;
794 smtp_write_command(&outblock
, FALSE
, "RSET\r\n") >= 0 &&
795 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
798 smtp_write_command(&outblock
, FALSE
, "MAIL FROM:<%s>\r\n",
799 from_address
) >= 0 &&
800 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
803 else done
= FALSE
; /* Some timeout/connection problem */
806 /* If the host is accepting all local parts, as determined by the "random"
807 check, we don't need to waste time doing any further checking. */
809 if (new_domain_record
.random_result
!= ccache_accept
&& done
)
811 /* Get the rcpt_include_affixes flag from the transport if there is one,
812 but assume FALSE if there is not. */
815 smtp_write_command(&outblock
, FALSE
, "RCPT TO:<%.1000s>\r\n",
816 transport_rcpt_address(addr
,
817 (addr
->transport
== NULL
)? FALSE
:
818 addr
->transport
->rcpt_include_affixes
)) >= 0 &&
819 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
823 new_address_record
.result
= ccache_accept
;
824 else if (errno
== 0 && responsebuffer
[0] == '5')
826 *failure_ptr
= US
"recipient";
827 new_address_record
.result
= ccache_reject
;
830 /* Do postmaster check if requested; if a full check is required, we
831 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
833 if (done
&& pm_mailfrom
!= NULL
)
835 /*XXX not suitable for cutthrough - sequencing problems */
836 cutthrough_delivery
= FALSE
;
837 HDEBUG(D_acl
|D_v
) debug_printf("Cutthrough cancelled by presence of postmaster verify\n");
840 smtp_write_command(&outblock
, FALSE
, "RSET\r\n") >= 0 &&
841 smtp_read_response(&inblock
, responsebuffer
,
842 sizeof(responsebuffer
), '2', callout
) &&
844 smtp_write_command(&outblock
, FALSE
,
845 "MAIL FROM:<%s>\r\n", pm_mailfrom
) >= 0 &&
846 smtp_read_response(&inblock
, responsebuffer
,
847 sizeof(responsebuffer
), '2', callout
) &&
849 /* First try using the current domain */
852 smtp_write_command(&outblock
, FALSE
,
853 "RCPT TO:<postmaster@%.1000s>\r\n", addr
->domain
) >= 0 &&
854 smtp_read_response(&inblock
, responsebuffer
,
855 sizeof(responsebuffer
), '2', callout
)
860 /* If that doesn't work, and a full check is requested,
861 try without the domain. */
864 (options
& vopt_callout_fullpm
) != 0 &&
865 smtp_write_command(&outblock
, FALSE
,
866 "RCPT TO:<postmaster>\r\n") >= 0 &&
867 smtp_read_response(&inblock
, responsebuffer
,
868 sizeof(responsebuffer
), '2', callout
)
871 /* Sort out the cache record */
873 new_domain_record
.postmaster_stamp
= time(NULL
);
876 new_domain_record
.postmaster_result
= ccache_accept
;
877 else if (errno
== 0 && responsebuffer
[0] == '5')
879 *failure_ptr
= US
"postmaster";
880 setflag(addr
, af_verify_pmfail
);
881 new_domain_record
.postmaster_result
= ccache_reject
;
884 } /* Random not accepted */
885 } /* MAIL FROM: accepted */
887 /* For any failure of the main check, other than a negative response, we just
888 close the connection and carry on. We can identify a negative response by the
889 fact that errno is zero. For I/O errors it will be non-zero
891 Set up different error texts for logging and for sending back to the caller
892 as an SMTP response. Log in all cases, using a one-line format. For sender
893 callouts, give a full response to the caller, but for recipient callouts,
894 don't give the IP address because this may be an internal host whose identity
895 is not to be widely broadcast. */
899 if (errno
== ETIMEDOUT
)
901 HDEBUG(D_verify
) debug_printf("SMTP timeout\n");
906 if (*responsebuffer
== 0) Ustrcpy(responsebuffer
, US
"connection dropped");
909 string_sprintf("response to \"%s\" from %s [%s] was: %s",
910 big_buffer
, host
->name
, host
->address
,
911 string_printing(responsebuffer
));
913 addr
->user_message
= is_recipient
?
914 string_sprintf("Callout verification failed:\n%s", responsebuffer
)
916 string_sprintf("Called: %s\nSent: %s\nResponse: %s",
917 host
->address
, big_buffer
, responsebuffer
);
919 /* Hard rejection ends the process */
921 if (responsebuffer
[0] == '5') /* Address rejected */
929 /* End the SMTP conversation and close the connection. */
931 /* Cutthrough - on a successfull connect and recipient-verify with use-sender
932 and we have no cutthrough conn so far
933 here is where we want to leave the conn open */
934 if ( cutthrough_delivery
937 && (options
& (vopt_callout_recipsender
|vopt_callout_recippmaster
)) == vopt_callout_recipsender
938 && !random_local_part
943 cutthrough_fd
= outblock
.sock
; /* We assume no buffer in use in the outblock */
944 cutthrough_addr
= *addr
; /* Save the address_item for later logging */
945 cutthrough_addr
.host_used
= store_get(sizeof(host_item
));
946 cutthrough_addr
.host_used
->name
= host
->name
;
947 cutthrough_addr
.host_used
->address
= host
->address
;
948 cutthrough_addr
.host_used
->port
= port
;
950 *(cutthrough_addr
.parent
= store_get(sizeof(address_item
)))= *addr
->parent
;
951 ctblock
.buffer
= ctbuffer
;
952 ctblock
.buffersize
= sizeof(ctbuffer
);
953 ctblock
.ptr
= ctbuffer
;
954 /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */
955 ctblock
.sock
= cutthrough_fd
;
959 /* Ensure no cutthrough on multiple address verifies */
960 if (options
& vopt_callout_recipsender
)
961 cancel_cutthrough_connection("multiple verify calls");
962 if (send_quit
) (void)smtp_write_command(&outblock
, FALSE
, "QUIT\r\n");
965 tls_close(FALSE
, TRUE
);
967 (void)close(inblock
.sock
);
970 } /* Loop through all hosts, while !done */
973 /* If we get here with done == TRUE, a successful callout happened, and yield
974 will be set OK or FAIL according to the response to the RCPT command.
975 Otherwise, we looped through the hosts but couldn't complete the business.
976 However, there may be domain-specific information to cache in both cases.
978 The value of the result field in the new_domain record is ccache_unknown if
979 there was an error before or with MAIL FROM:, and errno was not zero,
980 implying some kind of I/O error. We don't want to write the cache in that case.
981 Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
983 if (!callout_no_cache
&& new_domain_record
.result
!= ccache_unknown
)
985 if ((dbm_file
= dbfn_open(US
"callout", O_RDWR
|O_CREAT
, &dbblock
, FALSE
))
988 HDEBUG(D_verify
) debug_printf("callout cache: not available\n");
992 (void)dbfn_write(dbm_file
, addr
->domain
, &new_domain_record
,
993 (int)sizeof(dbdata_callout_cache
));
994 HDEBUG(D_verify
) debug_printf("wrote callout cache domain record:\n"
995 " result=%d postmaster=%d random=%d\n",
996 new_domain_record
.result
,
997 new_domain_record
.postmaster_result
,
998 new_domain_record
.random_result
);
1002 /* If a definite result was obtained for the callout, cache it unless caching
1007 if (!callout_no_cache
&& new_address_record
.result
!= ccache_unknown
)
1009 if (dbm_file
== NULL
)
1010 dbm_file
= dbfn_open(US
"callout", O_RDWR
|O_CREAT
, &dbblock
, FALSE
);
1011 if (dbm_file
== NULL
)
1013 HDEBUG(D_verify
) debug_printf("no callout cache available\n");
1017 (void)dbfn_write(dbm_file
, address_key
, &new_address_record
,
1018 (int)sizeof(dbdata_callout_cache_address
));
1019 HDEBUG(D_verify
) debug_printf("wrote %s callout cache address record\n",
1020 (new_address_record
.result
== ccache_accept
)? "positive" : "negative");
1025 /* Failure to connect to any host, or any response other than 2xx or 5xx is a
1026 temporary error. If there was only one host, and a response was received, leave
1027 it alone if supplying details. Otherwise, give a generic response. */
1031 uschar
*dullmsg
= string_sprintf("Could not complete %s verify callout",
1032 is_recipient
? "recipient" : "sender");
1035 if (host_list
->next
!= NULL
|| addr
->message
== NULL
) addr
->message
= dullmsg
;
1037 addr
->user_message
= (!smtp_return_error_details
)? dullmsg
:
1038 string_sprintf("%s for <%s>.\n"
1039 "The mail server(s) for the domain may be temporarily unreachable, or\n"
1040 "they may be permanently unreachable from this server. In the latter case,\n%s",
1041 dullmsg
, addr
->address
,
1043 "the address will never be accepted."
1045 "you need to change the address or create an MX record for its domain\n"
1046 "if it is supposed to be generally accessible from the Internet.\n"
1047 "Talk to your mail administrator for details.");
1049 /* Force a specific error code */
1051 addr
->basic_errno
= ERRNO_CALLOUTDEFER
;
1054 /* Come here from within the cache-reading code on fast-track exit. */
1057 if (dbm_file
!= NULL
) dbfn_close(dbm_file
);
1063 /* Called after recipient-acl to get a cutthrough connection open when
1064 one was requested and a recipient-verify wasn't subsequently done.
1067 open_cutthrough_connection( address_item
* addr
)
1071 /* Use a recipient-verify-callout to set up the cutthrough connection. */
1072 /* We must use a copy of the address for verification, because it might
1076 HDEBUG(D_acl
) debug_printf("----------- start cutthrough setup ------------\n");
1077 (void) verify_address(&addr2
, NULL
,
1078 vopt_is_recipient
| vopt_callout_recipsender
| vopt_callout_no_cache
,
1079 CUTTHROUGH_CMD_TIMEOUT
, -1, -1,
1081 HDEBUG(D_acl
) debug_printf("----------- end cutthrough setup ------------\n");
1087 /* Send given number of bytes from the buffer */
1089 cutthrough_send(int n
)
1091 if(cutthrough_fd
< 0)
1096 (tls_out
.active
== cutthrough_fd
) ? tls_write(FALSE
, ctblock
.buffer
, n
) :
1098 send(cutthrough_fd
, ctblock
.buffer
, n
, 0) > 0
1101 transport_count
+= n
;
1102 ctblock
.ptr
= ctblock
.buffer
;
1106 HDEBUG(D_transport
|D_acl
) debug_printf("cutthrough_send failed: %s\n", strerror(errno
));
1113 _cutthrough_puts(uschar
* cp
, int n
)
1117 if(ctblock
.ptr
>= ctblock
.buffer
+ctblock
.buffersize
)
1118 if(!cutthrough_send(ctblock
.buffersize
))
1121 *ctblock
.ptr
++ = *cp
++;
1126 /* Buffered output of counted data block. Return boolean success */
1128 cutthrough_puts(uschar
* cp
, int n
)
1130 if (cutthrough_fd
< 0) return TRUE
;
1131 if (_cutthrough_puts(cp
, n
)) return TRUE
;
1132 cancel_cutthrough_connection("transmit failed");
1138 _cutthrough_flush_send( void )
1140 int n
= ctblock
.ptr
-ctblock
.buffer
;
1143 if(!cutthrough_send(n
))
1149 /* Send out any bufferred output. Return boolean success. */
1151 cutthrough_flush_send( void )
1153 if (_cutthrough_flush_send()) return TRUE
;
1154 cancel_cutthrough_connection("transmit failed");
1160 cutthrough_put_nl( void )
1162 return cutthrough_puts(US
"\r\n", 2);
1166 /* Get and check response from cutthrough target */
1168 cutthrough_response(char expect
, uschar
** copy
)
1170 smtp_inblock inblock
;
1171 uschar inbuffer
[4096];
1172 uschar responsebuffer
[4096];
1174 inblock
.buffer
= inbuffer
;
1175 inblock
.buffersize
= sizeof(inbuffer
);
1176 inblock
.ptr
= inbuffer
;
1177 inblock
.ptrend
= inbuffer
;
1178 inblock
.sock
= cutthrough_fd
;
1179 /* this relies on (inblock.sock == tls_out.active) */
1180 if(!smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
), expect
, CUTTHROUGH_DATA_TIMEOUT
))
1181 cancel_cutthrough_connection("target timeout on read");
1186 *copy
= cp
= string_copy(responsebuffer
);
1187 /* Trim the trailing end of line */
1188 cp
+= Ustrlen(responsebuffer
);
1189 if(cp
> *copy
&& cp
[-1] == '\n') *--cp
= '\0';
1190 if(cp
> *copy
&& cp
[-1] == '\r') *--cp
= '\0';
1193 return responsebuffer
[0];
1197 /* Negotiate dataphase with the cutthrough target, returning success boolean */
1199 cutthrough_predata( void )
1201 if(cutthrough_fd
< 0)
1204 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> DATA\n");
1205 cutthrough_puts(US
"DATA\r\n", 6);
1206 cutthrough_flush_send();
1208 /* Assume nothing buffered. If it was it gets ignored. */
1209 return cutthrough_response('3', NULL
) == '3';
1213 /* Buffered send of headers. Return success boolean. */
1214 /* Expands newlines to wire format (CR,NL). */
1215 /* Also sends header-terminating blank line. */
1217 cutthrough_headers_send( void )
1220 uschar
* cp1
, * cp2
;
1222 if(cutthrough_fd
< 0)
1225 for(h
= header_list
; h
!= NULL
; h
= h
->next
)
1226 if(h
->type
!= htype_old
&& h
->text
!= NULL
)
1227 for (cp1
= h
->text
; *cp1
&& (cp2
= Ustrchr(cp1
, '\n')); cp1
= cp2
+1)
1228 if( !cutthrough_puts(cp1
, cp2
-cp1
)
1229 || !cutthrough_put_nl())
1232 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>>(nl)\n");
1233 return cutthrough_put_nl();
1238 close_cutthrough_connection( const char * why
)
1240 if(cutthrough_fd
>= 0)
1242 /* We could be sending this after a bunch of data, but that is ok as
1243 the only way to cancel the transfer in dataphase is to drop the tcp
1244 conn before the final dot.
1246 ctblock
.ptr
= ctbuffer
;
1247 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> QUIT\n");
1248 _cutthrough_puts(US
"QUIT\r\n", 6); /* avoid recursion */
1249 _cutthrough_flush_send();
1250 /* No wait for response */
1253 tls_close(FALSE
, TRUE
);
1255 (void)close(cutthrough_fd
);
1257 HDEBUG(D_acl
) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why
);
1259 ctblock
.ptr
= ctbuffer
;
1263 cancel_cutthrough_connection( const char * why
)
1265 close_cutthrough_connection(why
);
1266 cutthrough_delivery
= FALSE
;
1272 /* Have senders final-dot. Send one to cutthrough target, and grab the response.
1273 Log an OK response as a transmission.
1274 Close the connection.
1275 Return smtp response-class digit.
1278 cutthrough_finaldot( void )
1280 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> .\n");
1282 /* Assume data finshed with new-line */
1283 if(!cutthrough_puts(US
".", 1) || !cutthrough_put_nl() || !cutthrough_flush_send())
1284 return cutthrough_addr
.message
;
1286 switch(cutthrough_response('2', &cutthrough_addr
.message
))
1289 delivery_log(LOG_MAIN
, &cutthrough_addr
, (int)'>', NULL
);
1290 close_cutthrough_connection("delivered");
1294 delivery_log(LOG_MAIN
, &cutthrough_addr
, 0, US
"tmp-reject from cutthrough after DATA:");
1298 delivery_log(LOG_MAIN
|LOG_REJECT
, &cutthrough_addr
, 0, US
"rejected after DATA:");
1304 return cutthrough_addr
.message
;
1309 /*************************************************
1310 * Copy error to toplevel address *
1311 *************************************************/
1313 /* This function is used when a verify fails or defers, to ensure that the
1314 failure or defer information is in the original toplevel address. This applies
1315 when an address is redirected to a single new address, and the failure or
1316 deferral happens to the child address.
1319 vaddr the verify address item
1320 addr the final address item
1323 Returns: the value of YIELD
1327 copy_error(address_item
*vaddr
, address_item
*addr
, int yield
)
1331 vaddr
->message
= addr
->message
;
1332 vaddr
->user_message
= addr
->user_message
;
1333 vaddr
->basic_errno
= addr
->basic_errno
;
1334 vaddr
->more_errno
= addr
->more_errno
;
1335 vaddr
->p
.address_data
= addr
->p
.address_data
;
1336 copyflag(vaddr
, addr
, af_pass_message
);
1344 /**************************************************
1345 * printf that automatically handles TLS if needed *
1346 ***************************************************/
1348 /* This function is used by verify_address() as a substitute for all fprintf()
1349 calls; a direct fprintf() will not produce output in a TLS SMTP session, such
1350 as a response to an EXPN command. smtp_in.c makes smtp_printf available but
1351 that assumes that we always use the smtp_out FILE* when not using TLS or the
1352 ssl buffer when we are. Instead we take a FILE* parameter and check to see if
1353 that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular
1357 f the candidate FILE* to write to
1358 format format string
1359 ... optional arguments
1365 static void PRINTF_FUNCTION(2,3)
1366 respond_printf(FILE *f
, const char *format
, ...)
1370 va_start(ap
, format
);
1371 if (smtp_out
&& (f
== smtp_out
))
1372 smtp_vprintf(format
, ap
);
1374 vfprintf(f
, format
, ap
);
1380 /*************************************************
1381 * Verify an email address *
1382 *************************************************/
1384 /* This function is used both for verification (-bv and at other times) and
1385 address testing (-bt), which is indicated by address_test_mode being set.
1388 vaddr contains the address to verify; the next field in this block
1390 f if not NULL, write the result to this file
1391 options various option bits:
1392 vopt_fake_sender => this sender verify is not for the real
1393 sender (it was verify=sender=xxxx or an address from a
1394 header line) - rewriting must not change sender_address
1395 vopt_is_recipient => this is a recipient address, otherwise
1396 it's a sender address - this affects qualification and
1397 rewriting and messages from callouts
1398 vopt_qualify => qualify an unqualified address; else error
1399 vopt_expn => called from SMTP EXPN command
1400 vopt_success_on_redirect => when a new address is generated
1401 the verification instantly succeeds
1403 These ones are used by do_callout() -- the options variable
1406 vopt_callout_fullpm => if postmaster check, do full one
1407 vopt_callout_no_cache => don't use callout cache
1408 vopt_callout_random => do the "random" thing
1409 vopt_callout_recipsender => use real sender for recipient
1410 vopt_callout_recippmaster => use postmaster for recipient
1412 callout if > 0, specifies that callout is required, and gives timeout
1413 for individual commands
1414 callout_overall if > 0, gives overall timeout for the callout function;
1415 if < 0, a default is used (see do_callout())
1416 callout_connect the connection timeout for callouts
1417 se_mailfrom when callout is requested to verify a sender, use this
1418 in MAIL FROM; NULL => ""
1419 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
1420 thing and use this as the sender address (may be "")
1422 routed if not NULL, set TRUE if routing succeeded, so we can
1423 distinguish between routing failed and callout failed
1425 Returns: OK address verified
1426 FAIL address failed to verify
1427 DEFER can't tell at present
1431 verify_address(address_item
*vaddr
, FILE *f
, int options
, int callout
,
1432 int callout_overall
, int callout_connect
, uschar
*se_mailfrom
,
1433 uschar
*pm_mailfrom
, BOOL
*routed
)
1436 BOOL full_info
= (f
== NULL
)? FALSE
: (debug_selector
!= 0);
1437 BOOL is_recipient
= (options
& vopt_is_recipient
) != 0;
1438 BOOL expn
= (options
& vopt_expn
) != 0;
1439 BOOL success_on_redirect
= (options
& vopt_success_on_redirect
) != 0;
1442 int verify_type
= expn
? v_expn
:
1443 address_test_mode
? v_none
:
1444 is_recipient
? v_recipient
: v_sender
;
1445 address_item
*addr_list
;
1446 address_item
*addr_new
= NULL
;
1447 address_item
*addr_remote
= NULL
;
1448 address_item
*addr_local
= NULL
;
1449 address_item
*addr_succeed
= NULL
;
1450 uschar
**failure_ptr
= is_recipient
?
1451 &recipient_verify_failure
: &sender_verify_failure
;
1452 uschar
*ko_prefix
, *cr
;
1453 uschar
*address
= vaddr
->address
;
1454 uschar
*save_sender
;
1455 uschar null_sender
[] = { 0 }; /* Ensure writeable memory */
1457 /* Clear, just in case */
1459 *failure_ptr
= NULL
;
1461 /* Set up a prefix and suffix for error message which allow us to use the same
1462 output statements both in EXPN mode (where an SMTP response is needed) and when
1463 debugging with an output file. */
1467 ko_prefix
= US
"553 ";
1470 else ko_prefix
= cr
= US
"";
1472 /* Add qualify domain if permitted; otherwise an unqualified address fails. */
1474 if (parse_find_at(address
) == NULL
)
1476 if ((options
& vopt_qualify
) == 0)
1479 respond_printf(f
, "%sA domain is required for \"%s\"%s\n",
1480 ko_prefix
, address
, cr
);
1481 *failure_ptr
= US
"qualify";
1484 address
= rewrite_address_qualify(address
, is_recipient
);
1489 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1490 debug_printf("%s %s\n", address_test_mode
? "Testing" : "Verifying", address
);
1493 /* Rewrite and report on it. Clear the domain and local part caches - these
1494 may have been set by domains and local part tests during an ACL. */
1496 if (global_rewrite_rules
!= NULL
)
1498 uschar
*old
= address
;
1499 address
= rewrite_address(address
, is_recipient
, FALSE
,
1500 global_rewrite_rules
, rewrite_existflags
);
1503 for (i
= 0; i
< (MAX_NAMED_LIST
* 2)/32; i
++) vaddr
->localpart_cache
[i
] = 0;
1504 for (i
= 0; i
< (MAX_NAMED_LIST
* 2)/32; i
++) vaddr
->domain_cache
[i
] = 0;
1505 if (f
!= NULL
&& !expn
) fprintf(f
, "Address rewritten as: %s\n", address
);
1509 /* If this is the real sender address, we must update sender_address at
1510 this point, because it may be referred to in the routers. */
1512 if ((options
& (vopt_fake_sender
|vopt_is_recipient
)) == 0)
1513 sender_address
= address
;
1515 /* If the address was rewritten to <> no verification can be done, and we have
1516 to return OK. This rewriting is permitted only for sender addresses; for other
1517 addresses, such rewriting fails. */
1519 if (address
[0] == 0) return OK
;
1521 /* Save a copy of the sender address for re-instating if we change it to <>
1522 while verifying a sender address (a nice bit of self-reference there). */
1524 save_sender
= sender_address
;
1526 /* Update the address structure with the possibly qualified and rewritten
1527 address. Set it up as the starting address on the chain of new addresses. */
1529 vaddr
->address
= address
;
1532 /* We need a loop, because an address can generate new addresses. We must also
1533 cope with generated pipes and files at the top level. (See also the code and
1534 comment in deliver.c.) However, it is usually the case that the router for
1535 user's .forward files has its verify flag turned off.
1537 If an address generates more than one child, the loop is used only when
1538 full_info is set, and this can only be set locally. Remote enquiries just get
1539 information about the top level address, not anything that it generated. */
1541 while (addr_new
!= NULL
)
1544 address_item
*addr
= addr_new
;
1546 addr_new
= addr
->next
;
1551 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1552 debug_printf("Considering %s\n", addr
->address
);
1555 /* Handle generated pipe, file or reply addresses. We don't get these
1556 when handling EXPN, as it does only one level of expansion. */
1558 if (testflag(addr
, af_pfr
))
1565 if (addr
->address
[0] == '>')
1567 allow
= testflag(addr
, af_allow_reply
);
1568 fprintf(f
, "%s -> mail %s", addr
->parent
->address
, addr
->address
+ 1);
1572 allow
= (addr
->address
[0] == '|')?
1573 testflag(addr
, af_allow_pipe
) : testflag(addr
, af_allow_file
);
1574 fprintf(f
, "%s -> %s", addr
->parent
->address
, addr
->address
);
1577 if (addr
->basic_errno
== ERRNO_BADTRANSPORT
)
1578 fprintf(f
, "\n*** Error in setting up pipe, file, or autoreply:\n"
1579 "%s\n", addr
->message
);
1581 fprintf(f
, "\n transport = %s\n", addr
->transport
->name
);
1583 fprintf(f
, " *** forbidden ***\n");
1588 /* Just in case some router parameter refers to it. */
1590 return_path
= (addr
->p
.errors_address
!= NULL
)?
1591 addr
->p
.errors_address
: sender_address
;
1593 /* Split the address into domain and local part, handling the %-hack if
1594 necessary, and then route it. While routing a sender address, set
1595 $sender_address to <> because that is what it will be if we were trying to
1596 send a bounce to the sender. */
1598 if (routed
!= NULL
) *routed
= FALSE
;
1599 if ((rc
= deliver_split_address(addr
)) == OK
)
1601 if (!is_recipient
) sender_address
= null_sender
;
1602 rc
= route_address(addr
, &addr_local
, &addr_remote
, &addr_new
,
1603 &addr_succeed
, verify_type
);
1604 sender_address
= save_sender
; /* Put back the real sender */
1607 /* If routing an address succeeded, set the flag that remembers, for use when
1608 an ACL cached a sender verify (in case a callout fails). Then if routing set
1609 up a list of hosts or the transport has a host list, and the callout option
1610 is set, and we aren't in a host checking run, do the callout verification,
1611 and set another flag that notes that a callout happened. */
1615 if (routed
!= NULL
) *routed
= TRUE
;
1618 host_item
*host_list
= addr
->host_list
;
1620 /* Make up some data for use in the case where there is no remote
1623 transport_feedback tf
= {
1624 NULL
, /* interface (=> any) */
1625 US
"smtp", /* port */
1626 US
"smtp", /* protocol */
1628 US
"$smtp_active_hostname", /* helo_data */
1629 FALSE
, /* hosts_override */
1630 FALSE
, /* hosts_randomize */
1631 FALSE
, /* gethostbyname */
1632 TRUE
, /* qualify_single */
1633 FALSE
/* search_parents */
1636 /* If verification yielded a remote transport, we want to use that
1637 transport's options, so as to mimic what would happen if we were really
1638 sending a message to this address. */
1640 if (addr
->transport
!= NULL
&& !addr
->transport
->info
->local
)
1642 (void)(addr
->transport
->setup
)(addr
->transport
, addr
, &tf
, 0, 0, NULL
);
1644 /* If the transport has hosts and the router does not, or if the
1645 transport is configured to override the router's hosts, we must build a
1646 host list of the transport's hosts, and find the IP addresses */
1648 if (tf
.hosts
!= NULL
&& (host_list
== NULL
|| tf
.hosts_override
))
1651 uschar
*save_deliver_domain
= deliver_domain
;
1652 uschar
*save_deliver_localpart
= deliver_localpart
;
1654 host_list
= NULL
; /* Ignore the router's hosts */
1656 deliver_domain
= addr
->domain
;
1657 deliver_localpart
= addr
->local_part
;
1658 s
= expand_string(tf
.hosts
);
1659 deliver_domain
= save_deliver_domain
;
1660 deliver_localpart
= save_deliver_localpart
;
1664 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to expand list of hosts "
1665 "\"%s\" in %s transport for callout: %s", tf
.hosts
,
1666 addr
->transport
->name
, expand_string_message
);
1671 uschar
*canonical_name
;
1672 host_item
*host
, *nexthost
;
1673 host_build_hostlist(&host_list
, s
, tf
.hosts_randomize
);
1675 /* Just ignore failures to find a host address. If we don't manage
1676 to find any addresses, the callout will defer. Note that more than
1677 one address may be found for a single host, which will result in
1678 additional host items being inserted into the chain. Hence we must
1679 save the next host first. */
1681 flags
= HOST_FIND_BY_A
;
1682 if (tf
.qualify_single
) flags
|= HOST_FIND_QUALIFY_SINGLE
;
1683 if (tf
.search_parents
) flags
|= HOST_FIND_SEARCH_PARENTS
;
1685 for (host
= host_list
; host
!= NULL
; host
= nexthost
)
1687 nexthost
= host
->next
;
1688 if (tf
.gethostbyname
||
1689 string_is_ip_address(host
->name
, NULL
) != 0)
1690 (void)host_find_byname(host
, NULL
, flags
, &canonical_name
, TRUE
);
1692 (void)host_find_bydns(host
, NULL
, flags
, NULL
, NULL
, NULL
,
1693 &canonical_name
, NULL
);
1699 /* Can only do a callout if we have at least one host! If the callout
1700 fails, it will have set ${sender,recipient}_verify_failure. */
1702 if (host_list
!= NULL
)
1704 HDEBUG(D_verify
) debug_printf("Attempting full verification using callout\n");
1705 if (host_checking
&& !host_checking_callout
)
1708 debug_printf("... callout omitted by default when host testing\n"
1709 "(Use -bhc if you want the callouts to happen.)\n");
1714 deliver_set_expansions(addr
);
1716 rc
= do_callout(addr
, host_list
, &tf
, callout
, callout_overall
,
1717 callout_connect
, options
, se_mailfrom
, pm_mailfrom
);
1722 HDEBUG(D_verify
) debug_printf("Cannot do callout: neither router nor "
1723 "transport provided a host list\n");
1728 /* Otherwise, any failure is a routing failure */
1730 else *failure_ptr
= US
"route";
1732 /* A router may return REROUTED if it has set up a child address as a result
1733 of a change of domain name (typically from widening). In this case we always
1734 want to continue to verify the new child. */
1736 if (rc
== REROUTED
) continue;
1738 /* Handle hard failures */
1745 address_item
*p
= addr
->parent
;
1747 respond_printf(f
, "%s%s %s", ko_prefix
,
1748 full_info
? addr
->address
: address
,
1749 address_test_mode
? "is undeliverable" : "failed to verify");
1750 if (!expn
&& admin_user
)
1752 if (addr
->basic_errno
> 0)
1753 respond_printf(f
, ": %s", strerror(addr
->basic_errno
));
1754 if (addr
->message
!= NULL
)
1755 respond_printf(f
, ": %s", addr
->message
);
1758 /* Show parents iff doing full info */
1760 if (full_info
) while (p
!= NULL
)
1762 respond_printf(f
, "%s\n <-- %s", cr
, p
->address
);
1765 respond_printf(f
, "%s\n", cr
);
1767 cancel_cutthrough_connection("routing hard fail");
1769 if (!full_info
) return copy_error(vaddr
, addr
, FAIL
);
1775 else if (rc
== DEFER
)
1780 address_item
*p
= addr
->parent
;
1781 respond_printf(f
, "%s%s cannot be resolved at this time", ko_prefix
,
1782 full_info
? addr
->address
: address
);
1783 if (!expn
&& admin_user
)
1785 if (addr
->basic_errno
> 0)
1786 respond_printf(f
, ": %s", strerror(addr
->basic_errno
));
1787 if (addr
->message
!= NULL
)
1788 respond_printf(f
, ": %s", addr
->message
);
1789 else if (addr
->basic_errno
<= 0)
1790 respond_printf(f
, ": unknown error");
1793 /* Show parents iff doing full info */
1795 if (full_info
) while (p
!= NULL
)
1797 respond_printf(f
, "%s\n <-- %s", cr
, p
->address
);
1800 respond_printf(f
, "%s\n", cr
);
1802 cancel_cutthrough_connection("routing soft fail");
1804 if (!full_info
) return copy_error(vaddr
, addr
, DEFER
);
1805 else if (yield
== OK
) yield
= DEFER
;
1808 /* If we are handling EXPN, we do not want to continue to route beyond
1809 the top level (whose address is in "address"). */
1813 uschar
*ok_prefix
= US
"250-";
1814 if (addr_new
== NULL
)
1816 if (addr_local
== NULL
&& addr_remote
== NULL
)
1817 respond_printf(f
, "250 mail to <%s> is discarded\r\n", address
);
1819 respond_printf(f
, "250 <%s>\r\n", address
);
1821 else while (addr_new
!= NULL
)
1823 address_item
*addr2
= addr_new
;
1824 addr_new
= addr2
->next
;
1825 if (addr_new
== NULL
) ok_prefix
= US
"250 ";
1826 respond_printf(f
, "%s<%s>\r\n", ok_prefix
, addr2
->address
);
1831 /* Successful routing other than EXPN. */
1835 /* Handle successful routing when short info wanted. Otherwise continue for
1836 other (generated) addresses. Short info is the operational case. Full info
1837 can be requested only when debug_selector != 0 and a file is supplied.
1839 There is a conflict between the use of aliasing as an alternate email
1840 address, and as a sort of mailing list. If an alias turns the incoming
1841 address into just one address (e.g. J.Caesar->jc44) you may well want to
1842 carry on verifying the generated address to ensure it is valid when
1843 checking incoming mail. If aliasing generates multiple addresses, you
1844 probably don't want to do this. Exim therefore treats the generation of
1845 just a single new address as a special case, and continues on to verify the
1846 generated address. */
1848 if (!full_info
&& /* Stop if short info wanted AND */
1849 (((addr_new
== NULL
|| /* No new address OR */
1850 addr_new
->next
!= NULL
|| /* More than one new address OR */
1851 testflag(addr_new
, af_pfr
))) /* New address is pfr */
1853 (addr_new
!= NULL
&& /* At least one new address AND */
1854 success_on_redirect
))) /* success_on_redirect is set */
1856 if (f
!= NULL
) fprintf(f
, "%s %s\n", address
,
1857 address_test_mode
? "is deliverable" : "verified");
1859 /* If we have carried on to verify a child address, we want the value
1860 of $address_data to be that of the child */
1862 vaddr
->p
.address_data
= addr
->p
.address_data
;
1866 } /* Loop for generated addresses */
1868 /* Display the full results of the successful routing, including any generated
1869 addresses. Control gets here only when full_info is set, which requires f not
1870 to be NULL, and this occurs only when a top-level verify is called with the
1871 debugging switch on.
1873 If there are no local and no remote addresses, and there were no pipes, files,
1874 or autoreplies, and there were no errors or deferments, the message is to be
1875 discarded, usually because of the use of :blackhole: in an alias file. */
1877 if (allok
&& addr_local
== NULL
&& addr_remote
== NULL
)
1879 fprintf(f
, "mail to %s is discarded\n", address
);
1883 for (addr_list
= addr_local
, i
= 0; i
< 2; addr_list
= addr_remote
, i
++)
1885 while (addr_list
!= NULL
)
1887 address_item
*addr
= addr_list
;
1888 address_item
*p
= addr
->parent
;
1889 addr_list
= addr
->next
;
1891 fprintf(f
, "%s", CS addr
->address
);
1892 #ifdef EXPERIMENTAL_SRS
1893 if(addr
->p
.srs_sender
)
1894 fprintf(f
, " [srs = %s]", addr
->p
.srs_sender
);
1897 /* If the address is a duplicate, show something about it. */
1899 if (!testflag(addr
, af_pfr
))
1902 if ((tnode
= tree_search(tree_duplicates
, addr
->unique
)) != NULL
)
1903 fprintf(f
, " [duplicate, would not be delivered]");
1904 else tree_add_duplicate(addr
->unique
, addr
);
1907 /* Now show its parents */
1911 fprintf(f
, "\n <-- %s", p
->address
);
1916 /* Show router, and transport */
1918 fprintf(f
, "router = %s, ", addr
->router
->name
);
1919 fprintf(f
, "transport = %s\n", (addr
->transport
== NULL
)? US
"unset" :
1920 addr
->transport
->name
);
1922 /* Show any hosts that are set up by a router unless the transport
1923 is going to override them; fiddle a bit to get a nice format. */
1925 if (addr
->host_list
!= NULL
&& addr
->transport
!= NULL
&&
1926 !addr
->transport
->overrides_hosts
)
1931 for (h
= addr
->host_list
; h
!= NULL
; h
= h
->next
)
1933 int len
= Ustrlen(h
->name
);
1934 if (len
> maxlen
) maxlen
= len
;
1935 len
= (h
->address
!= NULL
)? Ustrlen(h
->address
) : 7;
1936 if (len
> maxaddlen
) maxaddlen
= len
;
1938 for (h
= addr
->host_list
; h
!= NULL
; h
= h
->next
)
1940 int len
= Ustrlen(h
->name
);
1941 fprintf(f
, " host %s ", h
->name
);
1942 while (len
++ < maxlen
) fprintf(f
, " ");
1943 if (h
->address
!= NULL
)
1945 fprintf(f
, "[%s] ", h
->address
);
1946 len
= Ustrlen(h
->address
);
1948 else if (!addr
->transport
->info
->local
) /* Omit [unknown] for local */
1950 fprintf(f
, "[unknown] ");
1954 while (len
++ < maxaddlen
) fprintf(f
," ");
1955 if (h
->mx
>= 0) fprintf(f
, "MX=%d", h
->mx
);
1956 if (h
->port
!= PORT_NONE
) fprintf(f
, " port=%d", h
->port
);
1957 if (h
->status
== hstatus_unusable
) fprintf(f
, " ** unusable **");
1964 /* Will be DEFER or FAIL if any one address has, only for full_info (which is
1965 the -bv or -bt case). */
1973 /*************************************************
1974 * Check headers for syntax errors *
1975 *************************************************/
1977 /* This function checks those header lines that contain addresses, and verifies
1978 that all the addresses therein are syntactially correct.
1981 msgptr where to put an error message
1988 verify_check_headers(uschar
**msgptr
)
1994 for (h
= header_list
; h
!= NULL
&& yield
== OK
; h
= h
->next
)
1996 if (h
->type
!= htype_from
&&
1997 h
->type
!= htype_reply_to
&&
1998 h
->type
!= htype_sender
&&
1999 h
->type
!= htype_to
&&
2000 h
->type
!= htype_cc
&&
2001 h
->type
!= htype_bcc
)
2004 colon
= Ustrchr(h
->text
, ':');
2006 while (isspace(*s
)) s
++;
2008 /* Loop for multiple addresses in the header, enabling group syntax. Note
2009 that we have to reset this after the header has been scanned. */
2011 parse_allow_group
= TRUE
;
2015 uschar
*ss
= parse_find_address_end(s
, FALSE
);
2016 uschar
*recipient
, *errmess
;
2017 int terminator
= *ss
;
2018 int start
, end
, domain
;
2020 /* Temporarily terminate the string at this point, and extract the
2021 operative address within, allowing group syntax. */
2024 recipient
= parse_extract_address(s
,&errmess
,&start
,&end
,&domain
,FALSE
);
2027 /* Permit an unqualified address only if the message is local, or if the
2028 sending host is configured to be permitted to send them. */
2030 if (recipient
!= NULL
&& domain
== 0)
2032 if (h
->type
== htype_from
|| h
->type
== htype_sender
)
2034 if (!allow_unqualified_sender
) recipient
= NULL
;
2038 if (!allow_unqualified_recipient
) recipient
= NULL
;
2040 if (recipient
== NULL
) errmess
= US
"unqualified address not permitted";
2043 /* It's an error if no address could be extracted, except for the special
2044 case of an empty address. */
2046 if (recipient
== NULL
&& Ustrcmp(errmess
, "empty address") != 0)
2048 uschar
*verb
= US
"is";
2053 /* Arrange not to include any white space at the end in the
2054 error message or the header name. */
2056 while (t
> s
&& isspace(t
[-1])) t
--;
2057 while (tt
> h
->text
&& isspace(tt
[-1])) tt
--;
2059 /* Add the address that failed to the error message, since in a
2060 header with very many addresses it is sometimes hard to spot
2061 which one is at fault. However, limit the amount of address to
2062 quote - cases have been seen where, for example, a missing double
2063 quote in a humungous To: header creates an "address" that is longer
2064 than string_sprintf can handle. */
2073 *msgptr
= string_printing(
2074 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
2075 errmess
, tt
- h
->text
, h
->text
, verb
, len
, s
));
2078 break; /* Out of address loop */
2081 /* Advance to the next address */
2083 s
= ss
+ (terminator
? 1:0);
2084 while (isspace(*s
)) s
++;
2085 } /* Next address */
2087 parse_allow_group
= FALSE
;
2088 parse_found_group
= FALSE
;
2089 } /* Next header unless yield has been set FALSE */
2096 /*************************************************
2097 * Check for blind recipients *
2098 *************************************************/
2100 /* This function checks that every (envelope) recipient is mentioned in either
2101 the To: or Cc: header lines, thus detecting blind carbon copies.
2103 There are two ways of scanning that could be used: either scan the header lines
2104 and tick off the recipients, or scan the recipients and check the header lines.
2105 The original proposed patch did the former, but I have chosen to do the latter,
2106 because (a) it requires no memory and (b) will use fewer resources when there
2107 are many addresses in To: and/or Cc: and only one or two envelope recipients.
2110 Returns: OK if there are no blind recipients
2111 FAIL if there is at least one blind recipient
2115 verify_check_notblind(void)
2118 for (i
= 0; i
< recipients_count
; i
++)
2122 uschar
*address
= recipients_list
[i
].address
;
2124 for (h
= header_list
; !found
&& h
!= NULL
; h
= h
->next
)
2128 if (h
->type
!= htype_to
&& h
->type
!= htype_cc
) continue;
2130 colon
= Ustrchr(h
->text
, ':');
2132 while (isspace(*s
)) s
++;
2134 /* Loop for multiple addresses in the header, enabling group syntax. Note
2135 that we have to reset this after the header has been scanned. */
2137 parse_allow_group
= TRUE
;
2141 uschar
*ss
= parse_find_address_end(s
, FALSE
);
2142 uschar
*recipient
,*errmess
;
2143 int terminator
= *ss
;
2144 int start
, end
, domain
;
2146 /* Temporarily terminate the string at this point, and extract the
2147 operative address within, allowing group syntax. */
2150 recipient
= parse_extract_address(s
,&errmess
,&start
,&end
,&domain
,FALSE
);
2153 /* If we found a valid recipient that has a domain, compare it with the
2154 envelope recipient. Local parts are compared case-sensitively, domains
2155 case-insensitively. By comparing from the start with length "domain", we
2156 include the "@" at the end, which ensures that we are comparing the whole
2157 local part of each address. */
2159 if (recipient
!= NULL
&& domain
!= 0)
2161 found
= Ustrncmp(recipient
, address
, domain
) == 0 &&
2162 strcmpic(recipient
+ domain
, address
+ domain
) == 0;
2166 /* Advance to the next address */
2168 s
= ss
+ (terminator
? 1:0);
2169 while (isspace(*s
)) s
++;
2170 } /* Next address */
2172 parse_allow_group
= FALSE
;
2173 parse_found_group
= FALSE
;
2174 } /* Next header (if found is false) */
2176 if (!found
) return FAIL
;
2177 } /* Next recipient */
2184 /*************************************************
2185 * Find if verified sender *
2186 *************************************************/
2188 /* Usually, just a single address is verified as the sender of the message.
2189 However, Exim can be made to verify other addresses as well (often related in
2190 some way), and this is useful in some environments. There may therefore be a
2191 chain of such addresses that have previously been tested. This function finds
2192 whether a given address is on the chain.
2194 Arguments: the address to be verified
2195 Returns: pointer to an address item, or NULL
2199 verify_checked_sender(uschar
*sender
)
2202 for (addr
= sender_verified_list
; addr
!= NULL
; addr
= addr
->next
)
2203 if (Ustrcmp(sender
, addr
->address
) == 0) break;
2211 /*************************************************
2212 * Get valid header address *
2213 *************************************************/
2215 /* Scan the originator headers of the message, looking for an address that
2216 verifies successfully. RFC 822 says:
2218 o The "Sender" field mailbox should be sent notices of
2219 any problems in transport or delivery of the original
2220 messages. If there is no "Sender" field, then the
2221 "From" field mailbox should be used.
2223 o If the "Reply-To" field exists, then the reply should
2224 go to the addresses indicated in that field and not to
2225 the address(es) indicated in the "From" field.
2227 So we check a Sender field if there is one, else a Reply_to field, else a From
2228 field. As some strange messages may have more than one of these fields,
2229 especially if they are resent- fields, check all of them if there is more than
2233 user_msgptr points to where to put a user error message
2234 log_msgptr points to where to put a log error message
2235 callout timeout for callout check (passed to verify_address())
2236 callout_overall overall callout timeout (ditto)
2237 callout_connect connect callout timeout (ditto)
2238 se_mailfrom mailfrom for verify; NULL => ""
2239 pm_mailfrom sender for pm callout check (passed to verify_address())
2240 options callout options (passed to verify_address())
2241 verrno where to put the address basic_errno
2243 If log_msgptr is set to something without setting user_msgptr, the caller
2244 normally uses log_msgptr for both things.
2246 Returns: result of the verification attempt: OK, FAIL, or DEFER;
2247 FAIL is given if no appropriate headers are found
2251 verify_check_header_address(uschar
**user_msgptr
, uschar
**log_msgptr
,
2252 int callout
, int callout_overall
, int callout_connect
, uschar
*se_mailfrom
,
2253 uschar
*pm_mailfrom
, int options
, int *verrno
)
2255 static int header_types
[] = { htype_sender
, htype_reply_to
, htype_from
};
2260 for (i
= 0; i
< 3 && !done
; i
++)
2263 for (h
= header_list
; h
!= NULL
&& !done
; h
= h
->next
)
2265 int terminator
, new_ok
;
2266 uschar
*s
, *ss
, *endname
;
2268 if (h
->type
!= header_types
[i
]) continue;
2269 s
= endname
= Ustrchr(h
->text
, ':') + 1;
2271 /* Scan the addresses in the header, enabling group syntax. Note that we
2272 have to reset this after the header has been scanned. */
2274 parse_allow_group
= TRUE
;
2278 address_item
*vaddr
;
2280 while (isspace(*s
) || *s
== ',') s
++;
2281 if (*s
== 0) break; /* End of header */
2283 ss
= parse_find_address_end(s
, FALSE
);
2285 /* The terminator is a comma or end of header, but there may be white
2286 space preceding it (including newline for the last address). Move back
2287 past any white space so we can check against any cached envelope sender
2288 address verifications. */
2290 while (isspace(ss
[-1])) ss
--;
2294 HDEBUG(D_verify
) debug_printf("verifying %.*s header address %s\n",
2295 (int)(endname
- h
->text
), h
->text
, s
);
2297 /* See if we have already verified this address as an envelope sender,
2298 and if so, use the previous answer. */
2300 vaddr
= verify_checked_sender(s
);
2302 if (vaddr
!= NULL
&& /* Previously checked */
2303 (callout
<= 0 || /* No callout needed; OR */
2304 vaddr
->special_action
> 256)) /* Callout was done */
2306 new_ok
= vaddr
->special_action
& 255;
2307 HDEBUG(D_verify
) debug_printf("previously checked as envelope sender\n");
2308 *ss
= terminator
; /* Restore shortened string */
2311 /* Otherwise we run the verification now. We must restore the shortened
2312 string before running the verification, so the headers are correct, in
2313 case there is any rewriting. */
2317 int start
, end
, domain
;
2318 uschar
*address
= parse_extract_address(s
, log_msgptr
, &start
, &end
,
2323 /* If we found an empty address, just carry on with the next one, but
2324 kill the message. */
2326 if (address
== NULL
&& Ustrcmp(*log_msgptr
, "empty address") == 0)
2333 /* If verification failed because of a syntax error, fail this
2334 function, and ensure that the failing address gets added to the error
2337 if (address
== NULL
)
2340 while (ss
> s
&& isspace(ss
[-1])) ss
--;
2341 *log_msgptr
= string_sprintf("syntax error in '%.*s' header when "
2342 "scanning for sender: %s in \"%.*s\"",
2343 endname
- h
->text
, h
->text
, *log_msgptr
, ss
- s
, s
);
2349 /* Else go ahead with the sender verification. But it isn't *the*
2350 sender of the message, so set vopt_fake_sender to stop sender_address
2351 being replaced after rewriting or qualification. */
2355 vaddr
= deliver_make_addr(address
, FALSE
);
2356 new_ok
= verify_address(vaddr
, NULL
, options
| vopt_fake_sender
,
2357 callout
, callout_overall
, callout_connect
, se_mailfrom
,
2362 /* We now have the result, either newly found, or cached. If we are
2363 giving out error details, set a specific user error. This means that the
2364 last of these will be returned to the user if all three fail. We do not
2365 set a log message - the generic one below will be used. */
2369 *verrno
= vaddr
->basic_errno
;
2370 if (smtp_return_error_details
)
2372 *user_msgptr
= string_sprintf("Rejected after DATA: "
2373 "could not verify \"%.*s\" header address\n%s: %s",
2374 endname
- h
->text
, h
->text
, vaddr
->address
, vaddr
->message
);
2378 /* Success or defer */
2387 if (new_ok
== DEFER
) yield
= DEFER
;
2389 /* Move on to any more addresses in the header */
2392 } /* Next address */
2394 parse_allow_group
= FALSE
;
2395 parse_found_group
= FALSE
;
2396 } /* Next header, unless done */
2397 } /* Next header type unless done */
2399 if (yield
== FAIL
&& *log_msgptr
== NULL
)
2400 *log_msgptr
= US
"there is no valid sender in any header line";
2402 if (yield
== DEFER
&& *log_msgptr
== NULL
)
2403 *log_msgptr
= US
"all attempts to verify a sender in a header line deferred";
2411 /*************************************************
2412 * Get RFC 1413 identification *
2413 *************************************************/
2415 /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
2416 the timeout is set to zero, then the query is not done. There may also be lists
2417 of hosts and nets which are exempt. To guard against malefactors sending
2418 non-printing characters which could, for example, disrupt a message's headers,
2419 make sure the string consists of printing characters only.
2422 port the port to connect to; usually this is IDENT_PORT (113), but when
2423 running in the test harness with -bh a different value is used.
2427 Side effect: any received ident value is put in sender_ident (NULL otherwise)
2431 verify_get_ident(int port
)
2433 int sock
, host_af
, qlen
;
2434 int received_sender_port
, received_interface_port
, n
;
2436 uschar buffer
[2048];
2438 /* Default is no ident. Check whether we want to do an ident check for this
2441 sender_ident
= NULL
;
2442 if (rfc1413_query_timeout
<= 0 || verify_check_host(&rfc1413_hosts
) != OK
)
2445 DEBUG(D_ident
) debug_printf("doing ident callback\n");
2447 /* Set up a connection to the ident port of the remote host. Bind the local end
2448 to the incoming interface address. If the sender host address is an IPv6
2449 address, the incoming interface address will also be IPv6. */
2451 host_af
= (Ustrchr(sender_host_address
, ':') == NULL
)? AF_INET
: AF_INET6
;
2452 sock
= ip_socket(SOCK_STREAM
, host_af
);
2453 if (sock
< 0) return;
2455 if (ip_bind(sock
, host_af
, interface_address
, 0) < 0)
2457 DEBUG(D_ident
) debug_printf("bind socket for ident failed: %s\n",
2462 if (ip_connect(sock
, host_af
, sender_host_address
, port
, rfc1413_query_timeout
)
2465 if (errno
== ETIMEDOUT
&& (log_extra_selector
& LX_ident_timeout
) != 0)
2467 log_write(0, LOG_MAIN
, "ident connection to %s timed out",
2468 sender_host_address
);
2472 DEBUG(D_ident
) debug_printf("ident connection to %s failed: %s\n",
2473 sender_host_address
, strerror(errno
));
2478 /* Construct and send the query. */
2480 sprintf(CS buffer
, "%d , %d\r\n", sender_host_port
, interface_port
);
2481 qlen
= Ustrlen(buffer
);
2482 if (send(sock
, buffer
, qlen
, 0) < 0)
2484 DEBUG(D_ident
) debug_printf("ident send failed: %s\n", strerror(errno
));
2488 /* Read a response line. We put it into the rest of the buffer, using several
2489 recv() calls if necessary. */
2497 int size
= sizeof(buffer
) - (p
- buffer
);
2499 if (size
<= 0) goto END_OFF
; /* Buffer filled without seeing \n. */
2500 count
= ip_recv(sock
, p
, size
, rfc1413_query_timeout
);
2501 if (count
<= 0) goto END_OFF
; /* Read error or EOF */
2503 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
2504 generous, and accept a plain \n terminator as well. The only illegal
2507 for (pp
= p
; pp
< p
+ count
; pp
++)
2509 if (*pp
== 0) goto END_OFF
; /* Zero octet not allowed */
2512 if (pp
[-1] == '\r') pp
--;
2514 goto GOT_DATA
; /* Break out of both loops */
2518 /* Reached the end of the data without finding \n. Let the loop continue to
2519 read some more, if there is room. */
2526 /* We have received a line of data. Check it carefully. It must start with the
2527 same two port numbers that we sent, followed by data as defined by the RFC. For
2530 12345 , 25 : USERID : UNIX :root
2532 However, the amount of white space may be different to what we sent. In the
2533 "osname" field there may be several sub-fields, comma separated. The data we
2534 actually want to save follows the third colon. Some systems put leading spaces
2535 in it - we discard those. */
2537 if (sscanf(CS buffer
+ qlen
, "%d , %d%n", &received_sender_port
,
2538 &received_interface_port
, &n
) != 2 ||
2539 received_sender_port
!= sender_host_port
||
2540 received_interface_port
!= interface_port
)
2543 p
= buffer
+ qlen
+ n
;
2544 while(isspace(*p
)) p
++;
2545 if (*p
++ != ':') goto END_OFF
;
2546 while(isspace(*p
)) p
++;
2547 if (Ustrncmp(p
, "USERID", 6) != 0) goto END_OFF
;
2549 while(isspace(*p
)) p
++;
2550 if (*p
++ != ':') goto END_OFF
;
2551 while (*p
!= 0 && *p
!= ':') p
++;
2552 if (*p
++ == 0) goto END_OFF
;
2553 while(isspace(*p
)) p
++;
2554 if (*p
== 0) goto END_OFF
;
2556 /* The rest of the line is the data we want. We turn it into printing
2557 characters when we save it, so that it cannot mess up the format of any logging
2558 or Received: lines into which it gets inserted. We keep a maximum of 127
2561 sender_ident
= string_printing(string_copyn(p
, 127));
2562 DEBUG(D_ident
) debug_printf("sender_ident = %s\n", sender_ident
);
2572 /*************************************************
2573 * Match host to a single host-list item *
2574 *************************************************/
2576 /* This function compares a host (name or address) against a single item
2577 from a host list. The host name gets looked up if it is needed and is not
2578 already known. The function is called from verify_check_this_host() via
2579 match_check_list(), which is why most of its arguments are in a single block.
2582 arg the argument block (see below)
2583 ss the host-list item
2584 valueptr where to pass back looked up data, or NULL
2585 error for error message when returning ERROR
2588 host_name (a) the host name, or
2589 (b) NULL, implying use sender_host_name and
2590 sender_host_aliases, looking them up if required, or
2591 (c) the empty string, meaning that only IP address matches
2593 host_address the host address
2594 host_ipv4 the IPv4 address taken from an IPv6 one
2598 DEFER lookup deferred
2599 ERROR (a) failed to find the host name or IP address, or
2600 (b) unknown lookup type specified, or
2601 (c) host name encountered when only IP addresses are
2606 check_host(void *arg
, uschar
*ss
, uschar
**valueptr
, uschar
**error
)
2608 check_host_block
*cb
= (check_host_block
*)arg
;
2611 BOOL iplookup
= FALSE
;
2612 BOOL isquery
= FALSE
;
2613 BOOL isiponly
= cb
->host_name
!= NULL
&& cb
->host_name
[0] == 0;
2618 /* Optimize for the special case when the pattern is "*". */
2620 if (*ss
== '*' && ss
[1] == 0) return OK
;
2622 /* If the pattern is empty, it matches only in the case when there is no host -
2623 this can occur in ACL checking for SMTP input using the -bs option. In this
2624 situation, the host address is the empty string. */
2626 if (cb
->host_address
[0] == 0) return (*ss
== 0)? OK
: FAIL
;
2627 if (*ss
== 0) return FAIL
;
2629 /* If the pattern is precisely "@" then match against the primary host name,
2630 provided that host name matching is permitted; if it's "@[]" match against the
2631 local host's IP addresses. */
2637 if (isiponly
) return ERROR
;
2638 ss
= primary_hostname
;
2640 else if (Ustrcmp(ss
, "@[]") == 0)
2642 ip_address_item
*ip
;
2643 for (ip
= host_find_interfaces(); ip
!= NULL
; ip
= ip
->next
)
2644 if (Ustrcmp(ip
->address
, cb
->host_address
) == 0) return OK
;
2649 /* If the pattern is an IP address, optionally followed by a bitmask count, do
2650 a (possibly masked) comparision with the current IP address. */
2652 if (string_is_ip_address(ss
, &maskoffset
) != 0)
2653 return (host_is_in_net(cb
->host_address
, ss
, maskoffset
)? OK
: FAIL
);
2655 /* The pattern is not an IP address. A common error that people make is to omit
2656 one component of an IPv4 address, either by accident, or believing that, for
2657 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,
2658 which it isn't. (Those applications that do accept 1.2.3 as an IP address
2659 interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
2660 ancient specification.) To aid in debugging these cases, we give a specific
2661 error if the pattern contains only digits and dots or contains a slash preceded
2662 only by digits and dots (a slash at the start indicates a file name and of
2663 course slashes may be present in lookups, but not preceded only by digits and
2666 for (t
= ss
; isdigit(*t
) || *t
== '.'; t
++);
2667 if (*t
== 0 || (*t
== '/' && t
!= ss
))
2669 *error
= US
"malformed IPv4 address or address mask";
2673 /* See if there is a semicolon in the pattern */
2675 semicolon
= Ustrchr(ss
, ';');
2677 /* If we are doing an IP address only match, then all lookups must be IP
2678 address lookups, even if there is no "net-". */
2682 iplookup
= semicolon
!= NULL
;
2685 /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
2686 a lookup on a masked IP network, in textual form. We obey this code even if we
2687 have already set iplookup, so as to skip over the "net-" prefix and to set the
2688 mask length. The net- stuff really only applies to single-key lookups where the
2689 key is implicit. For query-style lookups the key is specified in the query.
2690 From release 4.30, the use of net- for query style is no longer needed, but we
2691 retain it for backward compatibility. */
2693 if (Ustrncmp(ss
, "net", 3) == 0 && semicolon
!= NULL
)
2696 for (t
= ss
+ 3; isdigit(*t
); t
++) mlen
= mlen
* 10 + *t
- '0';
2697 if (mlen
== 0 && t
== ss
+3) mlen
= -1; /* No mask supplied */
2698 iplookup
= (*t
++ == '-');
2702 /* Do the IP address lookup if that is indeed what we have */
2710 uschar
*filename
, *key
, *result
;
2713 /* Find the search type */
2715 search_type
= search_findtype(t
, semicolon
- t
);
2717 if (search_type
< 0) log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "%s",
2718 search_error_message
);
2720 /* Adjust parameters for the type of lookup. For a query-style lookup, there
2721 is no file name, and the "key" is just the query. For query-style with a file
2722 name, we have to fish the file off the start of the query. For a single-key
2723 lookup, the key is the current IP address, masked appropriately, and
2724 reconverted to text form, with the mask appended. For IPv6 addresses, specify
2725 dot separators instead of colons, except when the lookup type is "iplsearch".
2728 if (mac_islookup(search_type
, lookup_absfilequery
))
2730 filename
= semicolon
+ 1;
2732 while (*key
!= 0 && !isspace(*key
)) key
++;
2733 filename
= string_copyn(filename
, key
- filename
);
2734 while (isspace(*key
)) key
++;
2736 else if (mac_islookup(search_type
, lookup_querystyle
))
2739 key
= semicolon
+ 1;
2741 else /* Single-key style */
2743 int sep
= (Ustrcmp(lookup_list
[search_type
]->name
, "iplsearch") == 0)?
2745 insize
= host_aton(cb
->host_address
, incoming
);
2746 host_mask(insize
, incoming
, mlen
);
2747 (void)host_nmtoa(insize
, incoming
, mlen
, buffer
, sep
);
2749 filename
= semicolon
+ 1;
2752 /* Now do the actual lookup; note that there is no search_close() because
2753 of the caching arrangements. */
2755 handle
= search_open(filename
, search_type
, 0, NULL
, NULL
);
2756 if (handle
== NULL
) log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "%s",
2757 search_error_message
);
2758 result
= search_find(handle
, filename
, key
, -1, NULL
, 0, 0, NULL
);
2759 if (valueptr
!= NULL
) *valueptr
= result
;
2760 return (result
!= NULL
)? OK
: search_find_defer
? DEFER
: FAIL
;
2763 /* The pattern is not an IP address or network reference of any kind. That is,
2764 it is a host name pattern. If this is an IP only match, there's an error in the
2769 *error
= US
"cannot match host name in match_ip list";
2773 /* Check the characters of the pattern to see if they comprise only letters,
2774 digits, full stops, and hyphens (the constituents of domain names). Allow
2775 underscores, as they are all too commonly found. Sigh. Also, if
2776 allow_utf8_domains is set, allow top-bit characters. */
2778 for (t
= ss
; *t
!= 0; t
++)
2779 if (!isalnum(*t
) && *t
!= '.' && *t
!= '-' && *t
!= '_' &&
2780 (!allow_utf8_domains
|| *t
< 128)) break;
2782 /* If the pattern is a complete domain name, with no fancy characters, look up
2783 its IP address and match against that. Note that a multi-homed host will add
2784 items to the chain. */
2795 rc
= host_find_byname(&h
, NULL
, HOST_FIND_QUALIFY_SINGLE
, NULL
, FALSE
);
2796 if (rc
== HOST_FOUND
|| rc
== HOST_FOUND_LOCAL
)
2799 for (hh
= &h
; hh
!= NULL
; hh
= hh
->next
)
2801 if (host_is_in_net(hh
->address
, cb
->host_address
, 0)) return OK
;
2805 if (rc
== HOST_FIND_AGAIN
) return DEFER
;
2806 *error
= string_sprintf("failed to find IP address for %s", ss
);
2810 /* Almost all subsequent comparisons require the host name, and can be done
2811 using the general string matching function. When this function is called for
2812 outgoing hosts, the name is always given explicitly. If it is NULL, it means we
2813 must use sender_host_name and its aliases, looking them up if necessary. */
2815 if (cb
->host_name
!= NULL
) /* Explicit host name given */
2816 return match_check_string(cb
->host_name
, ss
, -1, TRUE
, TRUE
, TRUE
,
2819 /* Host name not given; in principle we need the sender host name and its
2820 aliases. However, for query-style lookups, we do not need the name if the
2821 query does not contain $sender_host_name. From release 4.23, a reference to
2822 $sender_host_name causes it to be looked up, so we don't need to do the lookup
2825 if ((semicolon
= Ustrchr(ss
, ';')) != NULL
)
2828 int partial
, affixlen
, starflags
, id
;
2831 id
= search_findtype_partial(ss
, &partial
, &affix
, &affixlen
, &starflags
);
2834 if (id
< 0) /* Unknown lookup type */
2836 log_write(0, LOG_MAIN
|LOG_PANIC
, "%s in host list item \"%s\"",
2837 search_error_message
, ss
);
2840 isquery
= mac_islookup(id
, lookup_querystyle
|lookup_absfilequery
);
2845 switch(match_check_string(US
"", ss
, -1, TRUE
, TRUE
, TRUE
, valueptr
))
2848 case DEFER
: return DEFER
;
2849 default: return FAIL
;
2853 /* Not a query-style lookup; must ensure the host name is present, and then we
2854 do a check on the name and all its aliases. */
2856 if (sender_host_name
== NULL
)
2858 HDEBUG(D_host_lookup
)
2859 debug_printf("sender host name required, to match against %s\n", ss
);
2860 if (host_lookup_failed
|| host_name_lookup() != OK
)
2862 *error
= string_sprintf("failed to find host name for %s",
2863 sender_host_address
);;
2866 host_build_sender_fullhost();
2869 /* Match on the sender host name, using the general matching function */
2871 switch(match_check_string(sender_host_name
, ss
, -1, TRUE
, TRUE
, TRUE
,
2875 case DEFER
: return DEFER
;
2878 /* If there are aliases, try matching on them. */
2880 aliases
= sender_host_aliases
;
2881 while (*aliases
!= NULL
)
2883 switch(match_check_string(*aliases
++, ss
, -1, TRUE
, TRUE
, TRUE
, valueptr
))
2886 case DEFER
: return DEFER
;
2895 /*************************************************
2896 * Check a specific host matches a host list *
2897 *************************************************/
2899 /* This function is passed a host list containing items in a number of
2900 different formats and the identity of a host. Its job is to determine whether
2901 the given host is in the set of hosts defined by the list. The host name is
2902 passed as a pointer so that it can be looked up if needed and not already
2903 known. This is commonly the case when called from verify_check_host() to check
2904 an incoming connection. When called from elsewhere the host name should usually
2907 This function is now just a front end to match_check_list(), which runs common
2908 code for scanning a list. We pass it the check_host() function to perform a
2912 listptr pointer to the host list
2913 cache_bits pointer to cache for named lists, or NULL
2914 host_name the host name or NULL, implying use sender_host_name and
2915 sender_host_aliases, looking them up if required
2916 host_address the IP address
2917 valueptr if not NULL, data from a lookup is passed back here
2919 Returns: OK if the host is in the defined set
2920 FAIL if the host is not in the defined set,
2921 DEFER if a data lookup deferred (not a host lookup)
2923 If the host name was needed in order to make a comparison, and could not be
2924 determined from the IP address, the result is FAIL unless the item
2925 "+allow_unknown" was met earlier in the list, in which case OK is returned. */
2928 verify_check_this_host(uschar
**listptr
, unsigned int *cache_bits
,
2929 uschar
*host_name
, uschar
*host_address
, uschar
**valueptr
)
2932 unsigned int *local_cache_bits
= cache_bits
;
2933 uschar
*save_host_address
= deliver_host_address
;
2934 check_host_block cb
;
2935 cb
.host_name
= host_name
;
2936 cb
.host_address
= host_address
;
2938 if (valueptr
!= NULL
) *valueptr
= NULL
;
2940 /* If the host address starts off ::ffff: it is an IPv6 address in
2941 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2944 cb
.host_ipv4
= (Ustrncmp(host_address
, "::ffff:", 7) == 0)?
2945 host_address
+ 7 : host_address
;
2947 /* During the running of the check, put the IP address into $host_address. In
2948 the case of calls from the smtp transport, it will already be there. However,
2949 in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
2950 the safe side, any existing setting is preserved, though as I write this
2951 (November 2004) I can't see any cases where it is actually needed. */
2953 deliver_host_address
= host_address
;
2954 rc
= match_check_list(
2955 listptr
, /* the list */
2956 0, /* separator character */
2957 &hostlist_anchor
, /* anchor pointer */
2958 &local_cache_bits
, /* cache pointer */
2959 check_host
, /* function for testing */
2960 &cb
, /* argument for function */
2961 MCL_HOST
, /* type of check */
2962 (host_address
== sender_host_address
)?
2963 US
"host" : host_address
, /* text for debugging */
2964 valueptr
); /* where to pass back data */
2965 deliver_host_address
= save_host_address
;
2972 /*************************************************
2973 * Check the remote host matches a list *
2974 *************************************************/
2976 /* This is a front end to verify_check_this_host(), created because checking
2977 the remote host is a common occurrence. With luck, a good compiler will spot
2978 the tail recursion and optimize it. If there's no host address, this is
2979 command-line SMTP input - check against an empty string for the address.
2982 listptr pointer to the host list
2984 Returns: the yield of verify_check_this_host(),
2985 i.e. OK, FAIL, or DEFER
2989 verify_check_host(uschar
**listptr
)
2991 return verify_check_this_host(listptr
, sender_host_cache
, NULL
,
2992 (sender_host_address
== NULL
)? US
"" : sender_host_address
, NULL
);
2999 /*************************************************
3000 * Invert an IP address *
3001 *************************************************/
3003 /* Originally just used for DNS xBL lists, now also used for the
3004 reverse_ip expansion operator.
3007 buffer where to put the answer
3008 address the address to invert
3012 invert_address(uschar
*buffer
, uschar
*address
)
3015 uschar
*bptr
= buffer
;
3017 /* If this is an IPv4 address mapped into IPv6 format, adjust the pointer
3018 to the IPv4 part only. */
3020 if (Ustrncmp(address
, "::ffff:", 7) == 0) address
+= 7;
3022 /* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is
3025 if (host_aton(address
, bin
) == 1)
3029 for (i
= 0; i
< 4; i
++)
3031 sprintf(CS bptr
, "%d.", x
& 255);
3032 while (*bptr
) bptr
++;
3037 /* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses
3038 in any DNS black lists, and the format in which they will be looked up is
3039 unknown. This is just a guess. */
3045 for (j
= 3; j
>= 0; j
--)
3048 for (i
= 0; i
< 8; i
++)
3050 sprintf(CS bptr
, "%x.", x
& 15);
3051 while (*bptr
) bptr
++;
3058 /* Remove trailing period -- this is needed so that both arbitrary
3059 dnsbl keydomains and inverted addresses may be combined with the
3060 same format string, "%s.%s" */
3067 /*************************************************
3068 * Perform a single dnsbl lookup *
3069 *************************************************/
3071 /* This function is called from verify_check_dnsbl() below. It is also called
3072 recursively from within itself when domain and domain_txt are different
3073 pointers, in order to get the TXT record from the alternate domain.
3076 domain the outer dnsbl domain
3077 domain_txt alternate domain to lookup TXT record on success; when the
3078 same domain is to be used, domain_txt == domain (that is,
3079 the pointers must be identical, not just the text)
3080 keydomain the current keydomain (for debug message)
3081 prepend subdomain to lookup (like keydomain, but
3082 reversed if IP address)
3083 iplist the list of matching IP addresses, or NULL for "any"
3084 bitmask true if bitmask matching is wanted
3085 match_type condition for 'succeed' result
3086 0 => Any RR in iplist (=)
3087 1 => No RR in iplist (!=)
3088 2 => All RRs in iplist (==)
3089 3 => Some RRs not in iplist (!==)
3090 the two bits are defined as MT_NOT and MT_ALL
3091 defer_return what to return for a defer
3093 Returns: OK if lookup succeeded
3098 one_check_dnsbl(uschar
*domain
, uschar
*domain_txt
, uschar
*keydomain
,
3099 uschar
*prepend
, uschar
*iplist
, BOOL bitmask
, int match_type
,
3105 dnsbl_cache_block
*cb
;
3106 int old_pool
= store_pool
;
3107 uschar query
[256]; /* DNS domain max length */
3109 /* Construct the specific query domainname */
3111 if (!string_format(query
, sizeof(query
), "%s.%s", prepend
, domain
))
3113 log_write(0, LOG_MAIN
|LOG_PANIC
, "dnslist query is too long "
3114 "(ignored): %s...", query
);
3118 /* Look for this query in the cache. */
3120 t
= tree_search(dnsbl_cache
, query
);
3122 /* If not cached from a previous lookup, we must do a DNS lookup, and
3123 cache the result in permanent memory. */
3127 store_pool
= POOL_PERM
;
3129 /* Set up a tree entry to cache the lookup */
3131 t
= store_get(sizeof(tree_node
) + Ustrlen(query
));
3132 Ustrcpy(t
->name
, query
);
3133 t
->data
.ptr
= cb
= store_get(sizeof(dnsbl_cache_block
));
3134 (void)tree_insertnode(&dnsbl_cache
, t
);
3136 /* Do the DNS loopup . */
3138 HDEBUG(D_dnsbl
) debug_printf("new DNS lookup for %s\n", query
);
3139 cb
->rc
= dns_basic_lookup(&dnsa
, query
, T_A
);
3140 cb
->text_set
= FALSE
;
3144 /* If the lookup succeeded, cache the RHS address. The code allows for
3145 more than one address - this was for complete generality and the possible
3146 use of A6 records. However, A6 records have been reduced to experimental
3147 status (August 2001) and may die out. So they may never get used at all,
3148 let alone in dnsbl records. However, leave the code here, just in case.
3150 Quite apart from one A6 RR generating multiple addresses, there are DNS
3151 lists that return more than one A record, so we must handle multiple
3152 addresses generated in that way as well. */
3154 if (cb
->rc
== DNS_SUCCEED
)
3157 dns_address
**addrp
= &(cb
->rhs
);
3158 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
3160 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
3162 if (rr
->type
== T_A
)
3164 dns_address
*da
= dns_address_from_rr(&dnsa
, rr
);
3168 while (da
->next
!= NULL
) da
= da
->next
;
3169 addrp
= &(da
->next
);
3174 /* If we didn't find any A records, change the return code. This can
3175 happen when there is a CNAME record but there are no A records for what
3178 if (cb
->rhs
== NULL
) cb
->rc
= DNS_NODATA
;
3181 store_pool
= old_pool
;
3184 /* Previous lookup was cached */
3188 HDEBUG(D_dnsbl
) debug_printf("using result of previous DNS lookup\n");
3192 /* We now have the result of the DNS lookup, either newly done, or cached
3193 from a previous call. If the lookup succeeded, check against the address
3194 list if there is one. This may be a positive equality list (introduced by
3195 "="), a negative equality list (introduced by "!="), a positive bitmask
3196 list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/
3198 if (cb
->rc
== DNS_SUCCEED
)
3200 dns_address
*da
= NULL
;
3201 uschar
*addlist
= cb
->rhs
->address
;
3203 /* For A and AAAA records, there may be multiple addresses from multiple
3204 records. For A6 records (currently not expected to be used) there may be
3205 multiple addresses from a single record. */
3207 for (da
= cb
->rhs
->next
; da
!= NULL
; da
= da
->next
)
3208 addlist
= string_sprintf("%s, %s", addlist
, da
->address
);
3210 HDEBUG(D_dnsbl
) debug_printf("DNS lookup for %s succeeded (yielding %s)\n",
3213 /* Address list check; this can be either for equality, or via a bitmask.
3214 In the latter case, all the bits must match. */
3218 for (da
= cb
->rhs
; da
!= NULL
; da
= da
->next
)
3222 uschar
*ptr
= iplist
;
3225 /* Handle exact matching */
3229 while ((res
= string_nextinlist(&ptr
, &ipsep
, ip
, sizeof(ip
))) != NULL
)
3231 if (Ustrcmp(CS da
->address
, ip
) == 0) break;
3235 /* Handle bitmask matching */
3242 /* At present, all known DNS blocking lists use A records, with
3243 IPv4 addresses on the RHS encoding the information they return. I
3244 wonder if this will linger on as the last vestige of IPv4 when IPv6
3245 is ubiquitous? Anyway, for now we use paranoia code to completely
3246 ignore IPv6 addresses. The default mask is 0, which always matches.
3247 We change this only for IPv4 addresses in the list. */
3249 if (host_aton(da
->address
, address
) == 1) mask
= address
[0];
3251 /* Scan the returned addresses, skipping any that are IPv6 */
3253 while ((res
= string_nextinlist(&ptr
, &ipsep
, ip
, sizeof(ip
))) != NULL
)
3255 if (host_aton(ip
, address
) != 1) continue;
3256 if ((address
[0] & mask
) == address
[0]) break;
3262 (a) An IP address in an any ('=') list matched, or
3263 (b) No IP address in an all ('==') list matched
3265 then we're done searching. */
3267 if (((match_type
& MT_ALL
) != 0) == (res
== NULL
)) break;
3270 /* If da == NULL, either
3272 (a) No IP address in an any ('=') list matched, or
3273 (b) An IP address in an all ('==') list didn't match
3275 so behave as if the DNSBL lookup had not succeeded, i.e. the host is not on
3278 if ((match_type
== MT_NOT
|| match_type
== MT_ALL
) != (da
== NULL
))
3286 res
= US
"was no match";
3289 res
= US
"was an exclude match";
3292 res
= US
"was an IP address that did not match";
3295 res
= US
"were no IP addresses that did not match";
3298 debug_printf("=> but we are not accepting this block class because\n");
3299 debug_printf("=> there %s for %s%c%s\n",
3301 ((match_type
& MT_ALL
) == 0)? "" : "=",
3302 bitmask
? '&' : '=', iplist
);
3308 /* Either there was no IP list, or the record matched, implying that the
3309 domain is on the list. We now want to find a corresponding TXT record. If an
3310 alternate domain is specified for the TXT record, call this function
3311 recursively to look that up; this has the side effect of re-checking that
3312 there is indeed an A record at the alternate domain. */
3314 if (domain_txt
!= domain
)
3315 return one_check_dnsbl(domain_txt
, domain_txt
, keydomain
, prepend
, NULL
,
3316 FALSE
, match_type
, defer_return
);
3318 /* If there is no alternate domain, look up a TXT record in the main domain
3319 if it has not previously been cached. */
3323 cb
->text_set
= TRUE
;
3324 if (dns_basic_lookup(&dnsa
, query
, T_TXT
) == DNS_SUCCEED
)
3327 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
3329 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
3330 if (rr
->type
== T_TXT
) break;
3333 int len
= (rr
->data
)[0];
3334 if (len
> 511) len
= 127;
3335 store_pool
= POOL_PERM
;
3336 cb
->text
= string_sprintf("%.*s", len
, (const uschar
*)(rr
->data
+1));
3337 store_pool
= old_pool
;
3342 dnslist_value
= addlist
;
3343 dnslist_text
= cb
->text
;
3347 /* There was a problem with the DNS lookup */
3349 if (cb
->rc
!= DNS_NOMATCH
&& cb
->rc
!= DNS_NODATA
)
3351 log_write(L_dnslist_defer
, LOG_MAIN
,
3352 "DNS list lookup defer (probably timeout) for %s: %s", query
,
3353 (defer_return
== OK
)? US
"assumed in list" :
3354 (defer_return
== FAIL
)? US
"assumed not in list" :
3355 US
"returned DEFER");
3356 return defer_return
;
3359 /* No entry was found in the DNS; continue for next domain */
3363 debug_printf("DNS lookup for %s failed\n", query
);
3364 debug_printf("=> that means %s is not listed at %s\n",
3374 /*************************************************
3375 * Check host against DNS black lists *
3376 *************************************************/
3378 /* This function runs checks against a list of DNS black lists, until one
3379 matches. Each item on the list can be of the form
3381 domain=ip-address/key
3383 The domain is the right-most domain that is used for the query, for example,
3384 blackholes.mail-abuse.org. If the IP address is present, there is a match only
3385 if the DNS lookup returns a matching IP address. Several addresses may be
3386 given, comma-separated, for example: x.y.z=127.0.0.1,127.0.0.2.
3388 If no key is given, what is looked up in the domain is the inverted IP address
3389 of the current client host. If a key is given, it is used to construct the
3390 domain for the lookup. For example:
3392 dsn.rfc-ignorant.org/$sender_address_domain
3394 After finding a match in the DNS, the domain is placed in $dnslist_domain, and
3395 then we check for a TXT record for an error message, and if found, save its
3396 value in $dnslist_text. We also cache everything in a tree, to optimize
3399 The TXT record is normally looked up in the same domain as the A record, but
3400 when many lists are combined in a single DNS domain, this will not be a very
3401 specific message. It is possible to specify a different domain for looking up
3402 TXT records; this is given before the main domain, comma-separated. For
3405 dnslists = http.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.2 : \
3406 socks.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.3
3408 The caching ensures that only one lookup in dnsbl.sorbs.net is done.
3410 Note: an address for testing RBL is 192.203.178.39
3411 Note: an address for testing DUL is 192.203.178.4
3412 Note: a domain for testing RFCI is example.tld.dsn.rfc-ignorant.org
3415 listptr the domain/address/data list
3417 Returns: OK successful lookup (i.e. the address is on the list), or
3418 lookup deferred after +include_unknown
3419 FAIL name not found, or no data found for the given type, or
3420 lookup deferred after +exclude_unknown (default)
3421 DEFER lookup failure, if +defer_unknown was set
3425 verify_check_dnsbl(uschar
**listptr
)
3428 int defer_return
= FAIL
;
3429 uschar
*list
= *listptr
;
3432 uschar buffer
[1024];
3433 uschar revadd
[128]; /* Long enough for IPv6 address */
3435 /* Indicate that the inverted IP address is not yet set up */
3439 /* In case this is the first time the DNS resolver is being used. */
3441 dns_init(FALSE
, FALSE
);
3443 /* Loop through all the domains supplied, until something matches */
3445 while ((domain
= string_nextinlist(&list
, &sep
, buffer
, sizeof(buffer
))) != NULL
)
3448 BOOL bitmask
= FALSE
;
3455 HDEBUG(D_dnsbl
) debug_printf("DNS list check: %s\n", domain
);
3457 /* Deal with special values that change the behaviour on defer */
3459 if (domain
[0] == '+')
3461 if (strcmpic(domain
, US
"+include_unknown") == 0) defer_return
= OK
;
3462 else if (strcmpic(domain
, US
"+exclude_unknown") == 0) defer_return
= FAIL
;
3463 else if (strcmpic(domain
, US
"+defer_unknown") == 0) defer_return
= DEFER
;
3465 log_write(0, LOG_MAIN
|LOG_PANIC
, "unknown item in dnslist (ignored): %s",
3470 /* See if there's explicit data to be looked up */
3472 key
= Ustrchr(domain
, '/');
3473 if (key
!= NULL
) *key
++ = 0;
3475 /* See if there's a list of addresses supplied after the domain name. This is
3476 introduced by an = or a & character; if preceded by = we require all matches
3477 and if preceded by ! we invert the result. */
3479 iplist
= Ustrchr(domain
, '=');
3483 iplist
= Ustrchr(domain
, '&');
3486 if (iplist
!= NULL
) /* Found either = or & */
3488 if (iplist
> domain
&& iplist
[-1] == '!') /* Handle preceding ! */
3490 match_type
|= MT_NOT
;
3494 *iplist
++ = 0; /* Terminate domain, move on */
3496 /* If we found = (bitmask == FALSE), check for == or =& */
3498 if (!bitmask
&& (*iplist
== '=' || *iplist
== '&'))
3500 bitmask
= *iplist
++ == '&';
3501 match_type
|= MT_ALL
;
3505 /* If there is a comma in the domain, it indicates that a second domain for
3506 looking up TXT records is provided, before the main domain. Otherwise we must
3507 set domain_txt == domain. */
3509 domain_txt
= domain
;
3510 comma
= Ustrchr(domain
, ',');
3517 /* Check that what we have left is a sensible domain name. There is no reason
3518 why these domains should in fact use the same syntax as hosts and email
3519 domains, but in practice they seem to. However, there is little point in
3520 actually causing an error here, because that would no doubt hold up incoming
3521 mail. Instead, I'll just log it. */
3523 for (s
= domain
; *s
!= 0; s
++)
3525 if (!isalnum(*s
) && *s
!= '-' && *s
!= '.' && *s
!= '_')
3527 log_write(0, LOG_MAIN
, "dnslists domain \"%s\" contains "
3528 "strange characters - is this right?", domain
);
3533 /* Check the alternate domain if present */
3535 if (domain_txt
!= domain
) for (s
= domain_txt
; *s
!= 0; s
++)
3537 if (!isalnum(*s
) && *s
!= '-' && *s
!= '.' && *s
!= '_')
3539 log_write(0, LOG_MAIN
, "dnslists domain \"%s\" contains "
3540 "strange characters - is this right?", domain_txt
);
3545 /* If there is no key string, construct the query by adding the domain name
3546 onto the inverted host address, and perform a single DNS lookup. */
3550 if (sender_host_address
== NULL
) return FAIL
; /* can never match */
3551 if (revadd
[0] == 0) invert_address(revadd
, sender_host_address
);
3552 rc
= one_check_dnsbl(domain
, domain_txt
, sender_host_address
, revadd
,
3553 iplist
, bitmask
, match_type
, defer_return
);
3556 dnslist_domain
= string_copy(domain_txt
);
3557 dnslist_matched
= string_copy(sender_host_address
);
3558 HDEBUG(D_dnsbl
) debug_printf("=> that means %s is listed at %s\n",
3559 sender_host_address
, dnslist_domain
);
3561 if (rc
!= FAIL
) return rc
; /* OK or DEFER */
3564 /* If there is a key string, it can be a list of domains or IP addresses to
3565 be concatenated with the main domain. */
3572 uschar keybuffer
[256];
3573 uschar keyrevadd
[128];
3575 while ((keydomain
= string_nextinlist(&key
, &keysep
, keybuffer
,
3576 sizeof(keybuffer
))) != NULL
)
3578 uschar
*prepend
= keydomain
;
3580 if (string_is_ip_address(keydomain
, NULL
) != 0)
3582 invert_address(keyrevadd
, keydomain
);
3583 prepend
= keyrevadd
;
3586 rc
= one_check_dnsbl(domain
, domain_txt
, keydomain
, prepend
, iplist
,
3587 bitmask
, match_type
, defer_return
);
3591 dnslist_domain
= string_copy(domain_txt
);
3592 dnslist_matched
= string_copy(keydomain
);
3593 HDEBUG(D_dnsbl
) debug_printf("=> that means %s is listed at %s\n",
3594 keydomain
, dnslist_domain
);
3598 /* If the lookup deferred, remember this fact. We keep trying the rest
3599 of the list to see if we get a useful result, and if we don't, we return
3600 DEFER at the end. */
3602 if (rc
== DEFER
) defer
= TRUE
;
3603 } /* continue with next keystring domain/address */
3605 if (defer
) return DEFER
;
3607 } /* continue with next dnsdb outer domain */
3612 /* End of verify.c */