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
&&
605 verify_check_this_host(&(ob
->hosts_verify_avoid_tls
), NULL
, host
->name
,
606 host
->address
, NULL
) != OK
609 uschar buffer2
[4096];
611 && !(done
= smtp_write_command(&outblock
, FALSE
, "STARTTLS\r\n") >= 0))
614 /* If there is an I/O error, transmission of this message is deferred. If
615 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
616 false, we also defer. However, if there is a temporary rejection of STARTTLS
617 and tls_tempfail_tryclear is true, or if there is an outright rejection of
618 STARTTLS, we carry on. This means we will try to send the message in clear,
619 unless the host is in hosts_require_tls (tested below). */
621 if (!smtps
&& !smtp_read_response(&inblock
, buffer2
, sizeof(buffer2
), '2',
622 ob
->command_timeout
))
624 if (errno
!= 0 || buffer2
[0] == 0 ||
625 (buffer2
[0] == '4' && !ob
->tls_tempfail_tryclear
))
627 Ustrncpy(responsebuffer
, buffer2
, sizeof(responsebuffer
));
629 goto RESPONSE_FAILED
;
633 /* STARTTLS accepted or ssl-on-connect: try to negotiate a TLS session. */
636 int rc
= tls_client_start(inblock
.sock
, host
, addr
,
637 ob
->tls_certificate
, ob
->tls_privatekey
,
639 ob
->tls_verify_certificates
, ob
->tls_crl
,
640 ob
->tls_require_ciphers
,
641 #ifdef EXPERIMENTAL_OCSP
642 ob
->hosts_require_ocsp
,
644 ob
->tls_dh_min_bits
, callout
);
646 /* TLS negotiation failed; give an error. Try in clear on a new connection,
647 if the options permit it for this host. */
650 if (rc
== DEFER
&& ob
->tls_tempfail_tryclear
&& !smtps
&&
651 verify_check_this_host(&(ob
->hosts_require_tls
), NULL
, host
->name
,
652 host
->address
, NULL
) != OK
)
654 (void)close(inblock
.sock
);
655 log_write(0, LOG_MAIN
, "TLS session failure: delivering unencrypted "
656 "to %s [%s] (not in hosts_require_tls)", host
->name
, host
->address
);
658 goto tls_retry_connection
;
660 /*save_errno = ERRNO_TLSFAILURE;*/
661 /*message = US"failure while setting up TLS session";*/
667 /* TLS session is set up. Copy info for logging. */
668 addr
->cipher
= tls_out
.cipher
;
669 addr
->peerdn
= tls_out
.peerdn
;
671 /* For SMTPS we need to wait for the initial OK response, then do HELO. */
673 goto smtps_redo_greeting
;
675 /* For STARTTLS we need to redo EHLO */
680 /* If the host is required to use a secure channel, ensure that we have one. */
681 if (tls_out
.active
< 0)
682 if (verify_check_this_host(&(ob
->hosts_require_tls
), NULL
, host
->name
,
683 host
->address
, NULL
) == OK
)
685 /*save_errno = ERRNO_TLSREQUIRED;*/
686 log_write(0, LOG_MAIN
, "a TLS session is required for %s [%s], but %s",
687 host
->name
, host
->address
,
688 tls_offered
? "an attempt to start TLS failed" : "the server did not offer TLS support");
693 #endif /*SUPPORT_TLS*/
695 done
= TRUE
; /* so far so good; have response to HELO */
697 /*XXX the EHLO response would be analyzed here for IGNOREQUOTA, SIZE, PIPELINING */
699 /* For now, transport_filter by cutthrough-delivery is not supported */
700 /* Need proper integration with the proper transport mechanism. */
701 if (cutthrough_delivery
&& addr
->transport
->filter_command
)
703 cutthrough_delivery
= FALSE
;
704 HDEBUG(D_acl
|D_v
) debug_printf("Cutthrough cancelled by presence of transport filter\n");
711 /* Clear down of the TLS, SMTP and TCP layers on error is handled below. */
714 /* Failure to accept HELO is cached; this blocks the whole domain for all
715 senders. I/O errors and defer responses are not cached. */
719 *failure_ptr
= US
"mail"; /* At or before MAIL */
720 if (errno
== 0 && responsebuffer
[0] == '5')
722 setflag(addr
, af_verify_nsfail
);
723 new_domain_record
.result
= ccache_reject
;
727 /* If we haven't authenticated, but are required to, give up. */
730 else done
= smtp_auth(responsebuffer
, sizeof(responsebuffer
),
731 addr
, host
, ob
, esmtp
, &inblock
, &outblock
) == OK
&&
733 /* Copy AUTH info for logging */
734 ( (addr
->authenticator
= client_authenticator
),
735 (addr
->auth_id
= client_authenticated_id
),
737 /* Build a mail-AUTH string (re-using responsebuffer for convenience */
738 !smtp_mail_auth_str(responsebuffer
, sizeof(responsebuffer
), addr
, ob
)
741 ( (addr
->auth_sndr
= client_authenticated_sender
),
743 /* Send the MAIL command */
744 (smtp_write_command(&outblock
, FALSE
, "MAIL FROM:<%s>%s\r\n",
745 from_address
, responsebuffer
) >= 0)
748 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
751 /* If the host does not accept MAIL FROM:<>, arrange to cache this
752 information, but again, don't record anything for an I/O error or a defer. Do
753 not cache rejections of MAIL when a non-empty sender has been used, because
754 that blocks the whole domain for all senders. */
758 *failure_ptr
= US
"mail"; /* At or before MAIL */
759 if (errno
== 0 && responsebuffer
[0] == '5')
761 setflag(addr
, af_verify_nsfail
);
762 if (from_address
[0] == 0)
763 new_domain_record
.result
= ccache_reject_mfnull
;
767 /* Otherwise, proceed to check a "random" address (if required), then the
768 given address, and the postmaster address (if required). Between each check,
769 issue RSET, because some servers accept only one recipient after MAIL
772 Before doing this, set the result in the domain cache record to "accept",
773 unless its previous value was ccache_reject_mfnull. In that case, the domain
774 rejects MAIL FROM:<> and we want to continue to remember that. When that is
775 the case, we have got here only in the case of a recipient verification with
776 a non-null sender. */
780 new_domain_record
.result
=
781 (old_domain_cache_result
== ccache_reject_mfnull
)?
782 ccache_reject_mfnull
: ccache_accept
;
784 /* Do the random local part check first */
786 if (random_local_part
!= NULL
)
788 uschar randombuffer
[1024];
790 smtp_write_command(&outblock
, FALSE
,
791 "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part
,
792 addr
->domain
) >= 0 &&
793 smtp_read_response(&inblock
, randombuffer
,
794 sizeof(randombuffer
), '2', callout
);
796 /* Remember when we last did a random test */
798 new_domain_record
.random_stamp
= time(NULL
);
800 /* If accepted, we aren't going to do any further tests below. */
804 new_domain_record
.random_result
= ccache_accept
;
807 /* Otherwise, cache a real negative response, and get back to the right
808 state to send RCPT. Unless there's some problem such as a dropped
809 connection, we expect to succeed, because the commands succeeded above. */
813 if (randombuffer
[0] == '5')
814 new_domain_record
.random_result
= ccache_reject
;
817 smtp_write_command(&outblock
, FALSE
, "RSET\r\n") >= 0 &&
818 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
821 smtp_write_command(&outblock
, FALSE
, "MAIL FROM:<%s>\r\n",
822 from_address
) >= 0 &&
823 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
826 else done
= FALSE
; /* Some timeout/connection problem */
829 /* If the host is accepting all local parts, as determined by the "random"
830 check, we don't need to waste time doing any further checking. */
832 if (new_domain_record
.random_result
!= ccache_accept
&& done
)
834 /* Get the rcpt_include_affixes flag from the transport if there is one,
835 but assume FALSE if there is not. */
838 smtp_write_command(&outblock
, FALSE
, "RCPT TO:<%.1000s>\r\n",
839 transport_rcpt_address(addr
,
840 (addr
->transport
== NULL
)? FALSE
:
841 addr
->transport
->rcpt_include_affixes
)) >= 0 &&
842 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
846 new_address_record
.result
= ccache_accept
;
847 else if (errno
== 0 && responsebuffer
[0] == '5')
849 *failure_ptr
= US
"recipient";
850 new_address_record
.result
= ccache_reject
;
853 /* Do postmaster check if requested; if a full check is required, we
854 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
856 if (done
&& pm_mailfrom
!= NULL
)
858 /*XXX not suitable for cutthrough - sequencing problems */
859 cutthrough_delivery
= FALSE
;
860 HDEBUG(D_acl
|D_v
) debug_printf("Cutthrough cancelled by presence of postmaster verify\n");
863 smtp_write_command(&outblock
, FALSE
, "RSET\r\n") >= 0 &&
864 smtp_read_response(&inblock
, responsebuffer
,
865 sizeof(responsebuffer
), '2', callout
) &&
867 smtp_write_command(&outblock
, FALSE
,
868 "MAIL FROM:<%s>\r\n", pm_mailfrom
) >= 0 &&
869 smtp_read_response(&inblock
, responsebuffer
,
870 sizeof(responsebuffer
), '2', callout
) &&
872 /* First try using the current domain */
875 smtp_write_command(&outblock
, FALSE
,
876 "RCPT TO:<postmaster@%.1000s>\r\n", addr
->domain
) >= 0 &&
877 smtp_read_response(&inblock
, responsebuffer
,
878 sizeof(responsebuffer
), '2', callout
)
883 /* If that doesn't work, and a full check is requested,
884 try without the domain. */
887 (options
& vopt_callout_fullpm
) != 0 &&
888 smtp_write_command(&outblock
, FALSE
,
889 "RCPT TO:<postmaster>\r\n") >= 0 &&
890 smtp_read_response(&inblock
, responsebuffer
,
891 sizeof(responsebuffer
), '2', callout
)
894 /* Sort out the cache record */
896 new_domain_record
.postmaster_stamp
= time(NULL
);
899 new_domain_record
.postmaster_result
= ccache_accept
;
900 else if (errno
== 0 && responsebuffer
[0] == '5')
902 *failure_ptr
= US
"postmaster";
903 setflag(addr
, af_verify_pmfail
);
904 new_domain_record
.postmaster_result
= ccache_reject
;
907 } /* Random not accepted */
908 } /* MAIL FROM: accepted */
910 /* For any failure of the main check, other than a negative response, we just
911 close the connection and carry on. We can identify a negative response by the
912 fact that errno is zero. For I/O errors it will be non-zero
914 Set up different error texts for logging and for sending back to the caller
915 as an SMTP response. Log in all cases, using a one-line format. For sender
916 callouts, give a full response to the caller, but for recipient callouts,
917 don't give the IP address because this may be an internal host whose identity
918 is not to be widely broadcast. */
922 if (errno
== ETIMEDOUT
)
924 HDEBUG(D_verify
) debug_printf("SMTP timeout\n");
929 if (*responsebuffer
== 0) Ustrcpy(responsebuffer
, US
"connection dropped");
932 string_sprintf("response to \"%s\" from %s [%s] was: %s",
933 big_buffer
, host
->name
, host
->address
,
934 string_printing(responsebuffer
));
936 addr
->user_message
= is_recipient
?
937 string_sprintf("Callout verification failed:\n%s", responsebuffer
)
939 string_sprintf("Called: %s\nSent: %s\nResponse: %s",
940 host
->address
, big_buffer
, responsebuffer
);
942 /* Hard rejection ends the process */
944 if (responsebuffer
[0] == '5') /* Address rejected */
952 /* End the SMTP conversation and close the connection. */
954 /* Cutthrough - on a successfull connect and recipient-verify with use-sender
955 and we have no cutthrough conn so far
956 here is where we want to leave the conn open */
957 if ( cutthrough_delivery
960 && (options
& (vopt_callout_recipsender
|vopt_callout_recippmaster
)) == vopt_callout_recipsender
961 && !random_local_part
966 cutthrough_fd
= outblock
.sock
; /* We assume no buffer in use in the outblock */
967 cutthrough_addr
= *addr
; /* Save the address_item for later logging */
968 cutthrough_addr
.host_used
= store_get(sizeof(host_item
));
969 cutthrough_addr
.host_used
->name
= host
->name
;
970 cutthrough_addr
.host_used
->address
= host
->address
;
971 cutthrough_addr
.host_used
->port
= port
;
973 *(cutthrough_addr
.parent
= store_get(sizeof(address_item
)))= *addr
->parent
;
974 ctblock
.buffer
= ctbuffer
;
975 ctblock
.buffersize
= sizeof(ctbuffer
);
976 ctblock
.ptr
= ctbuffer
;
977 /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */
978 ctblock
.sock
= cutthrough_fd
;
982 /* Ensure no cutthrough on multiple address verifies */
983 if (options
& vopt_callout_recipsender
)
984 cancel_cutthrough_connection("multiple verify calls");
985 if (send_quit
) (void)smtp_write_command(&outblock
, FALSE
, "QUIT\r\n");
988 tls_close(FALSE
, TRUE
);
990 (void)close(inblock
.sock
);
993 } /* Loop through all hosts, while !done */
996 /* If we get here with done == TRUE, a successful callout happened, and yield
997 will be set OK or FAIL according to the response to the RCPT command.
998 Otherwise, we looped through the hosts but couldn't complete the business.
999 However, there may be domain-specific information to cache in both cases.
1001 The value of the result field in the new_domain record is ccache_unknown if
1002 there was an error before or with MAIL FROM:, and errno was not zero,
1003 implying some kind of I/O error. We don't want to write the cache in that case.
1004 Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
1006 if (!callout_no_cache
&& new_domain_record
.result
!= ccache_unknown
)
1008 if ((dbm_file
= dbfn_open(US
"callout", O_RDWR
|O_CREAT
, &dbblock
, FALSE
))
1011 HDEBUG(D_verify
) debug_printf("callout cache: not available\n");
1015 (void)dbfn_write(dbm_file
, addr
->domain
, &new_domain_record
,
1016 (int)sizeof(dbdata_callout_cache
));
1017 HDEBUG(D_verify
) debug_printf("wrote callout cache domain record:\n"
1018 " result=%d postmaster=%d random=%d\n",
1019 new_domain_record
.result
,
1020 new_domain_record
.postmaster_result
,
1021 new_domain_record
.random_result
);
1025 /* If a definite result was obtained for the callout, cache it unless caching
1030 if (!callout_no_cache
&& new_address_record
.result
!= ccache_unknown
)
1032 if (dbm_file
== NULL
)
1033 dbm_file
= dbfn_open(US
"callout", O_RDWR
|O_CREAT
, &dbblock
, FALSE
);
1034 if (dbm_file
== NULL
)
1036 HDEBUG(D_verify
) debug_printf("no callout cache available\n");
1040 (void)dbfn_write(dbm_file
, address_key
, &new_address_record
,
1041 (int)sizeof(dbdata_callout_cache_address
));
1042 HDEBUG(D_verify
) debug_printf("wrote %s callout cache address record\n",
1043 (new_address_record
.result
== ccache_accept
)? "positive" : "negative");
1048 /* Failure to connect to any host, or any response other than 2xx or 5xx is a
1049 temporary error. If there was only one host, and a response was received, leave
1050 it alone if supplying details. Otherwise, give a generic response. */
1054 uschar
*dullmsg
= string_sprintf("Could not complete %s verify callout",
1055 is_recipient
? "recipient" : "sender");
1058 if (host_list
->next
!= NULL
|| addr
->message
== NULL
) addr
->message
= dullmsg
;
1060 addr
->user_message
= (!smtp_return_error_details
)? dullmsg
:
1061 string_sprintf("%s for <%s>.\n"
1062 "The mail server(s) for the domain may be temporarily unreachable, or\n"
1063 "they may be permanently unreachable from this server. In the latter case,\n%s",
1064 dullmsg
, addr
->address
,
1066 "the address will never be accepted."
1068 "you need to change the address or create an MX record for its domain\n"
1069 "if it is supposed to be generally accessible from the Internet.\n"
1070 "Talk to your mail administrator for details.");
1072 /* Force a specific error code */
1074 addr
->basic_errno
= ERRNO_CALLOUTDEFER
;
1077 /* Come here from within the cache-reading code on fast-track exit. */
1080 if (dbm_file
!= NULL
) dbfn_close(dbm_file
);
1086 /* Called after recipient-acl to get a cutthrough connection open when
1087 one was requested and a recipient-verify wasn't subsequently done.
1090 open_cutthrough_connection( address_item
* addr
)
1094 /* Use a recipient-verify-callout to set up the cutthrough connection. */
1095 /* We must use a copy of the address for verification, because it might
1099 HDEBUG(D_acl
) debug_printf("----------- start cutthrough setup ------------\n");
1100 (void) verify_address(&addr2
, NULL
,
1101 vopt_is_recipient
| vopt_callout_recipsender
| vopt_callout_no_cache
,
1102 CUTTHROUGH_CMD_TIMEOUT
, -1, -1,
1104 HDEBUG(D_acl
) debug_printf("----------- end cutthrough setup ------------\n");
1110 /* Send given number of bytes from the buffer */
1112 cutthrough_send(int n
)
1114 if(cutthrough_fd
< 0)
1119 (tls_out
.active
== cutthrough_fd
) ? tls_write(FALSE
, ctblock
.buffer
, n
) :
1121 send(cutthrough_fd
, ctblock
.buffer
, n
, 0) > 0
1124 transport_count
+= n
;
1125 ctblock
.ptr
= ctblock
.buffer
;
1129 HDEBUG(D_transport
|D_acl
) debug_printf("cutthrough_send failed: %s\n", strerror(errno
));
1136 _cutthrough_puts(uschar
* cp
, int n
)
1140 if(ctblock
.ptr
>= ctblock
.buffer
+ctblock
.buffersize
)
1141 if(!cutthrough_send(ctblock
.buffersize
))
1144 *ctblock
.ptr
++ = *cp
++;
1149 /* Buffered output of counted data block. Return boolean success */
1151 cutthrough_puts(uschar
* cp
, int n
)
1153 if (cutthrough_fd
< 0) return TRUE
;
1154 if (_cutthrough_puts(cp
, n
)) return TRUE
;
1155 cancel_cutthrough_connection("transmit failed");
1161 _cutthrough_flush_send( void )
1163 int n
= ctblock
.ptr
-ctblock
.buffer
;
1166 if(!cutthrough_send(n
))
1172 /* Send out any bufferred output. Return boolean success. */
1174 cutthrough_flush_send( void )
1176 if (_cutthrough_flush_send()) return TRUE
;
1177 cancel_cutthrough_connection("transmit failed");
1183 cutthrough_put_nl( void )
1185 return cutthrough_puts(US
"\r\n", 2);
1189 /* Get and check response from cutthrough target */
1191 cutthrough_response(char expect
, uschar
** copy
)
1193 smtp_inblock inblock
;
1194 uschar inbuffer
[4096];
1195 uschar responsebuffer
[4096];
1197 inblock
.buffer
= inbuffer
;
1198 inblock
.buffersize
= sizeof(inbuffer
);
1199 inblock
.ptr
= inbuffer
;
1200 inblock
.ptrend
= inbuffer
;
1201 inblock
.sock
= cutthrough_fd
;
1202 /* this relies on (inblock.sock == tls_out.active) */
1203 if(!smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
), expect
, CUTTHROUGH_DATA_TIMEOUT
))
1204 cancel_cutthrough_connection("target timeout on read");
1209 *copy
= cp
= string_copy(responsebuffer
);
1210 /* Trim the trailing end of line */
1211 cp
+= Ustrlen(responsebuffer
);
1212 if(cp
> *copy
&& cp
[-1] == '\n') *--cp
= '\0';
1213 if(cp
> *copy
&& cp
[-1] == '\r') *--cp
= '\0';
1216 return responsebuffer
[0];
1220 /* Negotiate dataphase with the cutthrough target, returning success boolean */
1222 cutthrough_predata( void )
1224 if(cutthrough_fd
< 0)
1227 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> DATA\n");
1228 cutthrough_puts(US
"DATA\r\n", 6);
1229 cutthrough_flush_send();
1231 /* Assume nothing buffered. If it was it gets ignored. */
1232 return cutthrough_response('3', NULL
) == '3';
1236 /* Buffered send of headers. Return success boolean. */
1237 /* Expands newlines to wire format (CR,NL). */
1238 /* Also sends header-terminating blank line. */
1240 cutthrough_headers_send( void )
1243 uschar
* cp1
, * cp2
;
1245 if(cutthrough_fd
< 0)
1248 for(h
= header_list
; h
!= NULL
; h
= h
->next
)
1249 if(h
->type
!= htype_old
&& h
->text
!= NULL
)
1250 for (cp1
= h
->text
; *cp1
&& (cp2
= Ustrchr(cp1
, '\n')); cp1
= cp2
+1)
1251 if( !cutthrough_puts(cp1
, cp2
-cp1
)
1252 || !cutthrough_put_nl())
1255 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>>(nl)\n");
1256 return cutthrough_put_nl();
1261 close_cutthrough_connection( const char * why
)
1263 if(cutthrough_fd
>= 0)
1265 /* We could be sending this after a bunch of data, but that is ok as
1266 the only way to cancel the transfer in dataphase is to drop the tcp
1267 conn before the final dot.
1269 ctblock
.ptr
= ctbuffer
;
1270 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> QUIT\n");
1271 _cutthrough_puts(US
"QUIT\r\n", 6); /* avoid recursion */
1272 _cutthrough_flush_send();
1273 /* No wait for response */
1276 tls_close(FALSE
, TRUE
);
1278 (void)close(cutthrough_fd
);
1280 HDEBUG(D_acl
) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why
);
1282 ctblock
.ptr
= ctbuffer
;
1286 cancel_cutthrough_connection( const char * why
)
1288 close_cutthrough_connection(why
);
1289 cutthrough_delivery
= FALSE
;
1295 /* Have senders final-dot. Send one to cutthrough target, and grab the response.
1296 Log an OK response as a transmission.
1297 Close the connection.
1298 Return smtp response-class digit.
1301 cutthrough_finaldot( void )
1303 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> .\n");
1305 /* Assume data finshed with new-line */
1306 if(!cutthrough_puts(US
".", 1) || !cutthrough_put_nl() || !cutthrough_flush_send())
1307 return cutthrough_addr
.message
;
1309 switch(cutthrough_response('2', &cutthrough_addr
.message
))
1312 delivery_log(LOG_MAIN
, &cutthrough_addr
, (int)'>', NULL
);
1313 close_cutthrough_connection("delivered");
1317 delivery_log(LOG_MAIN
, &cutthrough_addr
, 0, US
"tmp-reject from cutthrough after DATA:");
1321 delivery_log(LOG_MAIN
|LOG_REJECT
, &cutthrough_addr
, 0, US
"rejected after DATA:");
1327 return cutthrough_addr
.message
;
1332 /*************************************************
1333 * Copy error to toplevel address *
1334 *************************************************/
1336 /* This function is used when a verify fails or defers, to ensure that the
1337 failure or defer information is in the original toplevel address. This applies
1338 when an address is redirected to a single new address, and the failure or
1339 deferral happens to the child address.
1342 vaddr the verify address item
1343 addr the final address item
1346 Returns: the value of YIELD
1350 copy_error(address_item
*vaddr
, address_item
*addr
, int yield
)
1354 vaddr
->message
= addr
->message
;
1355 vaddr
->user_message
= addr
->user_message
;
1356 vaddr
->basic_errno
= addr
->basic_errno
;
1357 vaddr
->more_errno
= addr
->more_errno
;
1358 vaddr
->p
.address_data
= addr
->p
.address_data
;
1359 copyflag(vaddr
, addr
, af_pass_message
);
1367 /**************************************************
1368 * printf that automatically handles TLS if needed *
1369 ***************************************************/
1371 /* This function is used by verify_address() as a substitute for all fprintf()
1372 calls; a direct fprintf() will not produce output in a TLS SMTP session, such
1373 as a response to an EXPN command. smtp_in.c makes smtp_printf available but
1374 that assumes that we always use the smtp_out FILE* when not using TLS or the
1375 ssl buffer when we are. Instead we take a FILE* parameter and check to see if
1376 that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular
1380 f the candidate FILE* to write to
1381 format format string
1382 ... optional arguments
1388 static void PRINTF_FUNCTION(2,3)
1389 respond_printf(FILE *f
, const char *format
, ...)
1393 va_start(ap
, format
);
1394 if (smtp_out
&& (f
== smtp_out
))
1395 smtp_vprintf(format
, ap
);
1397 vfprintf(f
, format
, ap
);
1403 /*************************************************
1404 * Verify an email address *
1405 *************************************************/
1407 /* This function is used both for verification (-bv and at other times) and
1408 address testing (-bt), which is indicated by address_test_mode being set.
1411 vaddr contains the address to verify; the next field in this block
1413 f if not NULL, write the result to this file
1414 options various option bits:
1415 vopt_fake_sender => this sender verify is not for the real
1416 sender (it was verify=sender=xxxx or an address from a
1417 header line) - rewriting must not change sender_address
1418 vopt_is_recipient => this is a recipient address, otherwise
1419 it's a sender address - this affects qualification and
1420 rewriting and messages from callouts
1421 vopt_qualify => qualify an unqualified address; else error
1422 vopt_expn => called from SMTP EXPN command
1423 vopt_success_on_redirect => when a new address is generated
1424 the verification instantly succeeds
1426 These ones are used by do_callout() -- the options variable
1429 vopt_callout_fullpm => if postmaster check, do full one
1430 vopt_callout_no_cache => don't use callout cache
1431 vopt_callout_random => do the "random" thing
1432 vopt_callout_recipsender => use real sender for recipient
1433 vopt_callout_recippmaster => use postmaster for recipient
1435 callout if > 0, specifies that callout is required, and gives timeout
1436 for individual commands
1437 callout_overall if > 0, gives overall timeout for the callout function;
1438 if < 0, a default is used (see do_callout())
1439 callout_connect the connection timeout for callouts
1440 se_mailfrom when callout is requested to verify a sender, use this
1441 in MAIL FROM; NULL => ""
1442 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
1443 thing and use this as the sender address (may be "")
1445 routed if not NULL, set TRUE if routing succeeded, so we can
1446 distinguish between routing failed and callout failed
1448 Returns: OK address verified
1449 FAIL address failed to verify
1450 DEFER can't tell at present
1454 verify_address(address_item
*vaddr
, FILE *f
, int options
, int callout
,
1455 int callout_overall
, int callout_connect
, uschar
*se_mailfrom
,
1456 uschar
*pm_mailfrom
, BOOL
*routed
)
1459 BOOL full_info
= (f
== NULL
)? FALSE
: (debug_selector
!= 0);
1460 BOOL is_recipient
= (options
& vopt_is_recipient
) != 0;
1461 BOOL expn
= (options
& vopt_expn
) != 0;
1462 BOOL success_on_redirect
= (options
& vopt_success_on_redirect
) != 0;
1465 int verify_type
= expn
? v_expn
:
1466 address_test_mode
? v_none
:
1467 is_recipient
? v_recipient
: v_sender
;
1468 address_item
*addr_list
;
1469 address_item
*addr_new
= NULL
;
1470 address_item
*addr_remote
= NULL
;
1471 address_item
*addr_local
= NULL
;
1472 address_item
*addr_succeed
= NULL
;
1473 uschar
**failure_ptr
= is_recipient
?
1474 &recipient_verify_failure
: &sender_verify_failure
;
1475 uschar
*ko_prefix
, *cr
;
1476 uschar
*address
= vaddr
->address
;
1477 uschar
*save_sender
;
1478 uschar null_sender
[] = { 0 }; /* Ensure writeable memory */
1480 /* Clear, just in case */
1482 *failure_ptr
= NULL
;
1484 /* Set up a prefix and suffix for error message which allow us to use the same
1485 output statements both in EXPN mode (where an SMTP response is needed) and when
1486 debugging with an output file. */
1490 ko_prefix
= US
"553 ";
1493 else ko_prefix
= cr
= US
"";
1495 /* Add qualify domain if permitted; otherwise an unqualified address fails. */
1497 if (parse_find_at(address
) == NULL
)
1499 if ((options
& vopt_qualify
) == 0)
1502 respond_printf(f
, "%sA domain is required for \"%s\"%s\n",
1503 ko_prefix
, address
, cr
);
1504 *failure_ptr
= US
"qualify";
1507 address
= rewrite_address_qualify(address
, is_recipient
);
1512 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1513 debug_printf("%s %s\n", address_test_mode
? "Testing" : "Verifying", address
);
1516 /* Rewrite and report on it. Clear the domain and local part caches - these
1517 may have been set by domains and local part tests during an ACL. */
1519 if (global_rewrite_rules
!= NULL
)
1521 uschar
*old
= address
;
1522 address
= rewrite_address(address
, is_recipient
, FALSE
,
1523 global_rewrite_rules
, rewrite_existflags
);
1526 for (i
= 0; i
< (MAX_NAMED_LIST
* 2)/32; i
++) vaddr
->localpart_cache
[i
] = 0;
1527 for (i
= 0; i
< (MAX_NAMED_LIST
* 2)/32; i
++) vaddr
->domain_cache
[i
] = 0;
1528 if (f
!= NULL
&& !expn
) fprintf(f
, "Address rewritten as: %s\n", address
);
1532 /* If this is the real sender address, we must update sender_address at
1533 this point, because it may be referred to in the routers. */
1535 if ((options
& (vopt_fake_sender
|vopt_is_recipient
)) == 0)
1536 sender_address
= address
;
1538 /* If the address was rewritten to <> no verification can be done, and we have
1539 to return OK. This rewriting is permitted only for sender addresses; for other
1540 addresses, such rewriting fails. */
1542 if (address
[0] == 0) return OK
;
1544 /* Flip the legacy TLS-related variables over to the outbound set in case
1545 they're used in the context of a transport used by verification. Reset them
1546 at exit from this routine. */
1548 modify_variable(US
"tls_bits", &tls_out
.bits
);
1549 modify_variable(US
"tls_certificate_verified", &tls_out
.certificate_verified
);
1550 modify_variable(US
"tls_cipher", &tls_out
.cipher
);
1551 modify_variable(US
"tls_peerdn", &tls_out
.peerdn
);
1552 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1553 modify_variable(US
"tls_sni", &tls_out
.sni
);
1556 /* Save a copy of the sender address for re-instating if we change it to <>
1557 while verifying a sender address (a nice bit of self-reference there). */
1559 save_sender
= sender_address
;
1561 /* Update the address structure with the possibly qualified and rewritten
1562 address. Set it up as the starting address on the chain of new addresses. */
1564 vaddr
->address
= address
;
1567 /* We need a loop, because an address can generate new addresses. We must also
1568 cope with generated pipes and files at the top level. (See also the code and
1569 comment in deliver.c.) However, it is usually the case that the router for
1570 user's .forward files has its verify flag turned off.
1572 If an address generates more than one child, the loop is used only when
1573 full_info is set, and this can only be set locally. Remote enquiries just get
1574 information about the top level address, not anything that it generated. */
1576 while (addr_new
!= NULL
)
1579 address_item
*addr
= addr_new
;
1581 addr_new
= addr
->next
;
1586 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1587 debug_printf("Considering %s\n", addr
->address
);
1590 /* Handle generated pipe, file or reply addresses. We don't get these
1591 when handling EXPN, as it does only one level of expansion. */
1593 if (testflag(addr
, af_pfr
))
1600 if (addr
->address
[0] == '>')
1602 allow
= testflag(addr
, af_allow_reply
);
1603 fprintf(f
, "%s -> mail %s", addr
->parent
->address
, addr
->address
+ 1);
1607 allow
= (addr
->address
[0] == '|')?
1608 testflag(addr
, af_allow_pipe
) : testflag(addr
, af_allow_file
);
1609 fprintf(f
, "%s -> %s", addr
->parent
->address
, addr
->address
);
1612 if (addr
->basic_errno
== ERRNO_BADTRANSPORT
)
1613 fprintf(f
, "\n*** Error in setting up pipe, file, or autoreply:\n"
1614 "%s\n", addr
->message
);
1616 fprintf(f
, "\n transport = %s\n", addr
->transport
->name
);
1618 fprintf(f
, " *** forbidden ***\n");
1623 /* Just in case some router parameter refers to it. */
1625 return_path
= (addr
->p
.errors_address
!= NULL
)?
1626 addr
->p
.errors_address
: sender_address
;
1628 /* Split the address into domain and local part, handling the %-hack if
1629 necessary, and then route it. While routing a sender address, set
1630 $sender_address to <> because that is what it will be if we were trying to
1631 send a bounce to the sender. */
1633 if (routed
!= NULL
) *routed
= FALSE
;
1634 if ((rc
= deliver_split_address(addr
)) == OK
)
1636 if (!is_recipient
) sender_address
= null_sender
;
1637 rc
= route_address(addr
, &addr_local
, &addr_remote
, &addr_new
,
1638 &addr_succeed
, verify_type
);
1639 sender_address
= save_sender
; /* Put back the real sender */
1642 /* If routing an address succeeded, set the flag that remembers, for use when
1643 an ACL cached a sender verify (in case a callout fails). Then if routing set
1644 up a list of hosts or the transport has a host list, and the callout option
1645 is set, and we aren't in a host checking run, do the callout verification,
1646 and set another flag that notes that a callout happened. */
1650 if (routed
!= NULL
) *routed
= TRUE
;
1653 host_item
*host_list
= addr
->host_list
;
1655 /* Make up some data for use in the case where there is no remote
1658 transport_feedback tf
= {
1659 NULL
, /* interface (=> any) */
1660 US
"smtp", /* port */
1661 US
"smtp", /* protocol */
1663 US
"$smtp_active_hostname", /* helo_data */
1664 FALSE
, /* hosts_override */
1665 FALSE
, /* hosts_randomize */
1666 FALSE
, /* gethostbyname */
1667 TRUE
, /* qualify_single */
1668 FALSE
/* search_parents */
1671 /* If verification yielded a remote transport, we want to use that
1672 transport's options, so as to mimic what would happen if we were really
1673 sending a message to this address. */
1675 if (addr
->transport
!= NULL
&& !addr
->transport
->info
->local
)
1677 (void)(addr
->transport
->setup
)(addr
->transport
, addr
, &tf
, 0, 0, NULL
);
1679 /* If the transport has hosts and the router does not, or if the
1680 transport is configured to override the router's hosts, we must build a
1681 host list of the transport's hosts, and find the IP addresses */
1683 if (tf
.hosts
!= NULL
&& (host_list
== NULL
|| tf
.hosts_override
))
1686 uschar
*save_deliver_domain
= deliver_domain
;
1687 uschar
*save_deliver_localpart
= deliver_localpart
;
1689 host_list
= NULL
; /* Ignore the router's hosts */
1691 deliver_domain
= addr
->domain
;
1692 deliver_localpart
= addr
->local_part
;
1693 s
= expand_string(tf
.hosts
);
1694 deliver_domain
= save_deliver_domain
;
1695 deliver_localpart
= save_deliver_localpart
;
1699 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to expand list of hosts "
1700 "\"%s\" in %s transport for callout: %s", tf
.hosts
,
1701 addr
->transport
->name
, expand_string_message
);
1706 uschar
*canonical_name
;
1707 host_item
*host
, *nexthost
;
1708 host_build_hostlist(&host_list
, s
, tf
.hosts_randomize
);
1710 /* Just ignore failures to find a host address. If we don't manage
1711 to find any addresses, the callout will defer. Note that more than
1712 one address may be found for a single host, which will result in
1713 additional host items being inserted into the chain. Hence we must
1714 save the next host first. */
1716 flags
= HOST_FIND_BY_A
;
1717 if (tf
.qualify_single
) flags
|= HOST_FIND_QUALIFY_SINGLE
;
1718 if (tf
.search_parents
) flags
|= HOST_FIND_SEARCH_PARENTS
;
1720 for (host
= host_list
; host
!= NULL
; host
= nexthost
)
1722 nexthost
= host
->next
;
1723 if (tf
.gethostbyname
||
1724 string_is_ip_address(host
->name
, NULL
) != 0)
1725 (void)host_find_byname(host
, NULL
, flags
, &canonical_name
, TRUE
);
1727 (void)host_find_bydns(host
, NULL
, flags
, NULL
, NULL
, NULL
,
1728 &canonical_name
, NULL
);
1734 /* Can only do a callout if we have at least one host! If the callout
1735 fails, it will have set ${sender,recipient}_verify_failure. */
1737 if (host_list
!= NULL
)
1739 HDEBUG(D_verify
) debug_printf("Attempting full verification using callout\n");
1740 if (host_checking
&& !host_checking_callout
)
1743 debug_printf("... callout omitted by default when host testing\n"
1744 "(Use -bhc if you want the callouts to happen.)\n");
1749 deliver_set_expansions(addr
);
1751 rc
= do_callout(addr
, host_list
, &tf
, callout
, callout_overall
,
1752 callout_connect
, options
, se_mailfrom
, pm_mailfrom
);
1757 HDEBUG(D_verify
) debug_printf("Cannot do callout: neither router nor "
1758 "transport provided a host list\n");
1763 /* Otherwise, any failure is a routing failure */
1765 else *failure_ptr
= US
"route";
1767 /* A router may return REROUTED if it has set up a child address as a result
1768 of a change of domain name (typically from widening). In this case we always
1769 want to continue to verify the new child. */
1771 if (rc
== REROUTED
) continue;
1773 /* Handle hard failures */
1780 address_item
*p
= addr
->parent
;
1782 respond_printf(f
, "%s%s %s", ko_prefix
,
1783 full_info
? addr
->address
: address
,
1784 address_test_mode
? "is undeliverable" : "failed to verify");
1785 if (!expn
&& admin_user
)
1787 if (addr
->basic_errno
> 0)
1788 respond_printf(f
, ": %s", strerror(addr
->basic_errno
));
1789 if (addr
->message
!= NULL
)
1790 respond_printf(f
, ": %s", addr
->message
);
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 hard fail");
1806 yield
= copy_error(vaddr
, addr
, FAIL
);
1814 else if (rc
== DEFER
)
1819 address_item
*p
= addr
->parent
;
1820 respond_printf(f
, "%s%s cannot be resolved at this time", ko_prefix
,
1821 full_info
? addr
->address
: address
);
1822 if (!expn
&& admin_user
)
1824 if (addr
->basic_errno
> 0)
1825 respond_printf(f
, ": %s", strerror(addr
->basic_errno
));
1826 if (addr
->message
!= NULL
)
1827 respond_printf(f
, ": %s", addr
->message
);
1828 else if (addr
->basic_errno
<= 0)
1829 respond_printf(f
, ": unknown error");
1832 /* Show parents iff doing full info */
1834 if (full_info
) while (p
!= NULL
)
1836 respond_printf(f
, "%s\n <-- %s", cr
, p
->address
);
1839 respond_printf(f
, "%s\n", cr
);
1841 cancel_cutthrough_connection("routing soft fail");
1845 yield
= copy_error(vaddr
, addr
, DEFER
);
1848 else if (yield
== OK
) yield
= DEFER
;
1851 /* If we are handling EXPN, we do not want to continue to route beyond
1852 the top level (whose address is in "address"). */
1856 uschar
*ok_prefix
= US
"250-";
1857 if (addr_new
== NULL
)
1859 if (addr_local
== NULL
&& addr_remote
== NULL
)
1860 respond_printf(f
, "250 mail to <%s> is discarded\r\n", address
);
1862 respond_printf(f
, "250 <%s>\r\n", address
);
1864 else while (addr_new
!= NULL
)
1866 address_item
*addr2
= addr_new
;
1867 addr_new
= addr2
->next
;
1868 if (addr_new
== NULL
) ok_prefix
= US
"250 ";
1869 respond_printf(f
, "%s<%s>\r\n", ok_prefix
, addr2
->address
);
1875 /* Successful routing other than EXPN. */
1879 /* Handle successful routing when short info wanted. Otherwise continue for
1880 other (generated) addresses. Short info is the operational case. Full info
1881 can be requested only when debug_selector != 0 and a file is supplied.
1883 There is a conflict between the use of aliasing as an alternate email
1884 address, and as a sort of mailing list. If an alias turns the incoming
1885 address into just one address (e.g. J.Caesar->jc44) you may well want to
1886 carry on verifying the generated address to ensure it is valid when
1887 checking incoming mail. If aliasing generates multiple addresses, you
1888 probably don't want to do this. Exim therefore treats the generation of
1889 just a single new address as a special case, and continues on to verify the
1890 generated address. */
1892 if (!full_info
&& /* Stop if short info wanted AND */
1893 (((addr_new
== NULL
|| /* No new address OR */
1894 addr_new
->next
!= NULL
|| /* More than one new address OR */
1895 testflag(addr_new
, af_pfr
))) /* New address is pfr */
1897 (addr_new
!= NULL
&& /* At least one new address AND */
1898 success_on_redirect
))) /* success_on_redirect is set */
1900 if (f
!= NULL
) fprintf(f
, "%s %s\n", address
,
1901 address_test_mode
? "is deliverable" : "verified");
1903 /* If we have carried on to verify a child address, we want the value
1904 of $address_data to be that of the child */
1906 vaddr
->p
.address_data
= addr
->p
.address_data
;
1911 } /* Loop for generated addresses */
1913 /* Display the full results of the successful routing, including any generated
1914 addresses. Control gets here only when full_info is set, which requires f not
1915 to be NULL, and this occurs only when a top-level verify is called with the
1916 debugging switch on.
1918 If there are no local and no remote addresses, and there were no pipes, files,
1919 or autoreplies, and there were no errors or deferments, the message is to be
1920 discarded, usually because of the use of :blackhole: in an alias file. */
1922 if (allok
&& addr_local
== NULL
&& addr_remote
== NULL
)
1924 fprintf(f
, "mail to %s is discarded\n", address
);
1928 for (addr_list
= addr_local
, i
= 0; i
< 2; addr_list
= addr_remote
, i
++)
1930 while (addr_list
!= NULL
)
1932 address_item
*addr
= addr_list
;
1933 address_item
*p
= addr
->parent
;
1934 addr_list
= addr
->next
;
1936 fprintf(f
, "%s", CS addr
->address
);
1937 #ifdef EXPERIMENTAL_SRS
1938 if(addr
->p
.srs_sender
)
1939 fprintf(f
, " [srs = %s]", addr
->p
.srs_sender
);
1942 /* If the address is a duplicate, show something about it. */
1944 if (!testflag(addr
, af_pfr
))
1947 if ((tnode
= tree_search(tree_duplicates
, addr
->unique
)) != NULL
)
1948 fprintf(f
, " [duplicate, would not be delivered]");
1949 else tree_add_duplicate(addr
->unique
, addr
);
1952 /* Now show its parents */
1956 fprintf(f
, "\n <-- %s", p
->address
);
1961 /* Show router, and transport */
1963 fprintf(f
, "router = %s, ", addr
->router
->name
);
1964 fprintf(f
, "transport = %s\n", (addr
->transport
== NULL
)? US
"unset" :
1965 addr
->transport
->name
);
1967 /* Show any hosts that are set up by a router unless the transport
1968 is going to override them; fiddle a bit to get a nice format. */
1970 if (addr
->host_list
!= NULL
&& addr
->transport
!= NULL
&&
1971 !addr
->transport
->overrides_hosts
)
1976 for (h
= addr
->host_list
; h
!= NULL
; h
= h
->next
)
1978 int len
= Ustrlen(h
->name
);
1979 if (len
> maxlen
) maxlen
= len
;
1980 len
= (h
->address
!= NULL
)? Ustrlen(h
->address
) : 7;
1981 if (len
> maxaddlen
) maxaddlen
= len
;
1983 for (h
= addr
->host_list
; h
!= NULL
; h
= h
->next
)
1985 int len
= Ustrlen(h
->name
);
1986 fprintf(f
, " host %s ", h
->name
);
1987 while (len
++ < maxlen
) fprintf(f
, " ");
1988 if (h
->address
!= NULL
)
1990 fprintf(f
, "[%s] ", h
->address
);
1991 len
= Ustrlen(h
->address
);
1993 else if (!addr
->transport
->info
->local
) /* Omit [unknown] for local */
1995 fprintf(f
, "[unknown] ");
1999 while (len
++ < maxaddlen
) fprintf(f
," ");
2000 if (h
->mx
>= 0) fprintf(f
, "MX=%d", h
->mx
);
2001 if (h
->port
!= PORT_NONE
) fprintf(f
, " port=%d", h
->port
);
2002 if (h
->status
== hstatus_unusable
) fprintf(f
, " ** unusable **");
2009 /* Yield will be DEFER or FAIL if any one address has, only for full_info (which is
2010 the -bv or -bt case). */
2014 modify_variable(US
"tls_bits", &tls_in
.bits
);
2015 modify_variable(US
"tls_certificate_verified", &tls_in
.certificate_verified
);
2016 modify_variable(US
"tls_cipher", &tls_in
.cipher
);
2017 modify_variable(US
"tls_peerdn", &tls_in
.peerdn
);
2018 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
2019 modify_variable(US
"tls_sni", &tls_in
.sni
);
2028 /*************************************************
2029 * Check headers for syntax errors *
2030 *************************************************/
2032 /* This function checks those header lines that contain addresses, and verifies
2033 that all the addresses therein are syntactially correct.
2036 msgptr where to put an error message
2043 verify_check_headers(uschar
**msgptr
)
2049 for (h
= header_list
; h
!= NULL
&& yield
== OK
; h
= h
->next
)
2051 if (h
->type
!= htype_from
&&
2052 h
->type
!= htype_reply_to
&&
2053 h
->type
!= htype_sender
&&
2054 h
->type
!= htype_to
&&
2055 h
->type
!= htype_cc
&&
2056 h
->type
!= htype_bcc
)
2059 colon
= Ustrchr(h
->text
, ':');
2061 while (isspace(*s
)) s
++;
2063 /* Loop for multiple addresses in the header, enabling group syntax. Note
2064 that we have to reset this after the header has been scanned. */
2066 parse_allow_group
= TRUE
;
2070 uschar
*ss
= parse_find_address_end(s
, FALSE
);
2071 uschar
*recipient
, *errmess
;
2072 int terminator
= *ss
;
2073 int start
, end
, domain
;
2075 /* Temporarily terminate the string at this point, and extract the
2076 operative address within, allowing group syntax. */
2079 recipient
= parse_extract_address(s
,&errmess
,&start
,&end
,&domain
,FALSE
);
2082 /* Permit an unqualified address only if the message is local, or if the
2083 sending host is configured to be permitted to send them. */
2085 if (recipient
!= NULL
&& domain
== 0)
2087 if (h
->type
== htype_from
|| h
->type
== htype_sender
)
2089 if (!allow_unqualified_sender
) recipient
= NULL
;
2093 if (!allow_unqualified_recipient
) recipient
= NULL
;
2095 if (recipient
== NULL
) errmess
= US
"unqualified address not permitted";
2098 /* It's an error if no address could be extracted, except for the special
2099 case of an empty address. */
2101 if (recipient
== NULL
&& Ustrcmp(errmess
, "empty address") != 0)
2103 uschar
*verb
= US
"is";
2108 /* Arrange not to include any white space at the end in the
2109 error message or the header name. */
2111 while (t
> s
&& isspace(t
[-1])) t
--;
2112 while (tt
> h
->text
&& isspace(tt
[-1])) tt
--;
2114 /* Add the address that failed to the error message, since in a
2115 header with very many addresses it is sometimes hard to spot
2116 which one is at fault. However, limit the amount of address to
2117 quote - cases have been seen where, for example, a missing double
2118 quote in a humungous To: header creates an "address" that is longer
2119 than string_sprintf can handle. */
2128 *msgptr
= string_printing(
2129 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
2130 errmess
, tt
- h
->text
, h
->text
, verb
, len
, s
));
2133 break; /* Out of address loop */
2136 /* Advance to the next address */
2138 s
= ss
+ (terminator
? 1:0);
2139 while (isspace(*s
)) s
++;
2140 } /* Next address */
2142 parse_allow_group
= FALSE
;
2143 parse_found_group
= FALSE
;
2144 } /* Next header unless yield has been set FALSE */
2151 /*************************************************
2152 * Check for blind recipients *
2153 *************************************************/
2155 /* This function checks that every (envelope) recipient is mentioned in either
2156 the To: or Cc: header lines, thus detecting blind carbon copies.
2158 There are two ways of scanning that could be used: either scan the header lines
2159 and tick off the recipients, or scan the recipients and check the header lines.
2160 The original proposed patch did the former, but I have chosen to do the latter,
2161 because (a) it requires no memory and (b) will use fewer resources when there
2162 are many addresses in To: and/or Cc: and only one or two envelope recipients.
2165 Returns: OK if there are no blind recipients
2166 FAIL if there is at least one blind recipient
2170 verify_check_notblind(void)
2173 for (i
= 0; i
< recipients_count
; i
++)
2177 uschar
*address
= recipients_list
[i
].address
;
2179 for (h
= header_list
; !found
&& h
!= NULL
; h
= h
->next
)
2183 if (h
->type
!= htype_to
&& h
->type
!= htype_cc
) continue;
2185 colon
= Ustrchr(h
->text
, ':');
2187 while (isspace(*s
)) s
++;
2189 /* Loop for multiple addresses in the header, enabling group syntax. Note
2190 that we have to reset this after the header has been scanned. */
2192 parse_allow_group
= TRUE
;
2196 uschar
*ss
= parse_find_address_end(s
, FALSE
);
2197 uschar
*recipient
,*errmess
;
2198 int terminator
= *ss
;
2199 int start
, end
, domain
;
2201 /* Temporarily terminate the string at this point, and extract the
2202 operative address within, allowing group syntax. */
2205 recipient
= parse_extract_address(s
,&errmess
,&start
,&end
,&domain
,FALSE
);
2208 /* If we found a valid recipient that has a domain, compare it with the
2209 envelope recipient. Local parts are compared case-sensitively, domains
2210 case-insensitively. By comparing from the start with length "domain", we
2211 include the "@" at the end, which ensures that we are comparing the whole
2212 local part of each address. */
2214 if (recipient
!= NULL
&& domain
!= 0)
2216 found
= Ustrncmp(recipient
, address
, domain
) == 0 &&
2217 strcmpic(recipient
+ domain
, address
+ domain
) == 0;
2221 /* Advance to the next address */
2223 s
= ss
+ (terminator
? 1:0);
2224 while (isspace(*s
)) s
++;
2225 } /* Next address */
2227 parse_allow_group
= FALSE
;
2228 parse_found_group
= FALSE
;
2229 } /* Next header (if found is false) */
2231 if (!found
) return FAIL
;
2232 } /* Next recipient */
2239 /*************************************************
2240 * Find if verified sender *
2241 *************************************************/
2243 /* Usually, just a single address is verified as the sender of the message.
2244 However, Exim can be made to verify other addresses as well (often related in
2245 some way), and this is useful in some environments. There may therefore be a
2246 chain of such addresses that have previously been tested. This function finds
2247 whether a given address is on the chain.
2249 Arguments: the address to be verified
2250 Returns: pointer to an address item, or NULL
2254 verify_checked_sender(uschar
*sender
)
2257 for (addr
= sender_verified_list
; addr
!= NULL
; addr
= addr
->next
)
2258 if (Ustrcmp(sender
, addr
->address
) == 0) break;
2266 /*************************************************
2267 * Get valid header address *
2268 *************************************************/
2270 /* Scan the originator headers of the message, looking for an address that
2271 verifies successfully. RFC 822 says:
2273 o The "Sender" field mailbox should be sent notices of
2274 any problems in transport or delivery of the original
2275 messages. If there is no "Sender" field, then the
2276 "From" field mailbox should be used.
2278 o If the "Reply-To" field exists, then the reply should
2279 go to the addresses indicated in that field and not to
2280 the address(es) indicated in the "From" field.
2282 So we check a Sender field if there is one, else a Reply_to field, else a From
2283 field. As some strange messages may have more than one of these fields,
2284 especially if they are resent- fields, check all of them if there is more than
2288 user_msgptr points to where to put a user error message
2289 log_msgptr points to where to put a log error message
2290 callout timeout for callout check (passed to verify_address())
2291 callout_overall overall callout timeout (ditto)
2292 callout_connect connect callout timeout (ditto)
2293 se_mailfrom mailfrom for verify; NULL => ""
2294 pm_mailfrom sender for pm callout check (passed to verify_address())
2295 options callout options (passed to verify_address())
2296 verrno where to put the address basic_errno
2298 If log_msgptr is set to something without setting user_msgptr, the caller
2299 normally uses log_msgptr for both things.
2301 Returns: result of the verification attempt: OK, FAIL, or DEFER;
2302 FAIL is given if no appropriate headers are found
2306 verify_check_header_address(uschar
**user_msgptr
, uschar
**log_msgptr
,
2307 int callout
, int callout_overall
, int callout_connect
, uschar
*se_mailfrom
,
2308 uschar
*pm_mailfrom
, int options
, int *verrno
)
2310 static int header_types
[] = { htype_sender
, htype_reply_to
, htype_from
};
2315 for (i
= 0; i
< 3 && !done
; i
++)
2318 for (h
= header_list
; h
!= NULL
&& !done
; h
= h
->next
)
2320 int terminator
, new_ok
;
2321 uschar
*s
, *ss
, *endname
;
2323 if (h
->type
!= header_types
[i
]) continue;
2324 s
= endname
= Ustrchr(h
->text
, ':') + 1;
2326 /* Scan the addresses in the header, enabling group syntax. Note that we
2327 have to reset this after the header has been scanned. */
2329 parse_allow_group
= TRUE
;
2333 address_item
*vaddr
;
2335 while (isspace(*s
) || *s
== ',') s
++;
2336 if (*s
== 0) break; /* End of header */
2338 ss
= parse_find_address_end(s
, FALSE
);
2340 /* The terminator is a comma or end of header, but there may be white
2341 space preceding it (including newline for the last address). Move back
2342 past any white space so we can check against any cached envelope sender
2343 address verifications. */
2345 while (isspace(ss
[-1])) ss
--;
2349 HDEBUG(D_verify
) debug_printf("verifying %.*s header address %s\n",
2350 (int)(endname
- h
->text
), h
->text
, s
);
2352 /* See if we have already verified this address as an envelope sender,
2353 and if so, use the previous answer. */
2355 vaddr
= verify_checked_sender(s
);
2357 if (vaddr
!= NULL
&& /* Previously checked */
2358 (callout
<= 0 || /* No callout needed; OR */
2359 vaddr
->special_action
> 256)) /* Callout was done */
2361 new_ok
= vaddr
->special_action
& 255;
2362 HDEBUG(D_verify
) debug_printf("previously checked as envelope sender\n");
2363 *ss
= terminator
; /* Restore shortened string */
2366 /* Otherwise we run the verification now. We must restore the shortened
2367 string before running the verification, so the headers are correct, in
2368 case there is any rewriting. */
2372 int start
, end
, domain
;
2373 uschar
*address
= parse_extract_address(s
, log_msgptr
, &start
, &end
,
2378 /* If we found an empty address, just carry on with the next one, but
2379 kill the message. */
2381 if (address
== NULL
&& Ustrcmp(*log_msgptr
, "empty address") == 0)
2388 /* If verification failed because of a syntax error, fail this
2389 function, and ensure that the failing address gets added to the error
2392 if (address
== NULL
)
2395 while (ss
> s
&& isspace(ss
[-1])) ss
--;
2396 *log_msgptr
= string_sprintf("syntax error in '%.*s' header when "
2397 "scanning for sender: %s in \"%.*s\"",
2398 endname
- h
->text
, h
->text
, *log_msgptr
, ss
- s
, s
);
2404 /* Else go ahead with the sender verification. But it isn't *the*
2405 sender of the message, so set vopt_fake_sender to stop sender_address
2406 being replaced after rewriting or qualification. */
2410 vaddr
= deliver_make_addr(address
, FALSE
);
2411 new_ok
= verify_address(vaddr
, NULL
, options
| vopt_fake_sender
,
2412 callout
, callout_overall
, callout_connect
, se_mailfrom
,
2417 /* We now have the result, either newly found, or cached. If we are
2418 giving out error details, set a specific user error. This means that the
2419 last of these will be returned to the user if all three fail. We do not
2420 set a log message - the generic one below will be used. */
2424 *verrno
= vaddr
->basic_errno
;
2425 if (smtp_return_error_details
)
2427 *user_msgptr
= string_sprintf("Rejected after DATA: "
2428 "could not verify \"%.*s\" header address\n%s: %s",
2429 endname
- h
->text
, h
->text
, vaddr
->address
, vaddr
->message
);
2433 /* Success or defer */
2442 if (new_ok
== DEFER
) yield
= DEFER
;
2444 /* Move on to any more addresses in the header */
2447 } /* Next address */
2449 parse_allow_group
= FALSE
;
2450 parse_found_group
= FALSE
;
2451 } /* Next header, unless done */
2452 } /* Next header type unless done */
2454 if (yield
== FAIL
&& *log_msgptr
== NULL
)
2455 *log_msgptr
= US
"there is no valid sender in any header line";
2457 if (yield
== DEFER
&& *log_msgptr
== NULL
)
2458 *log_msgptr
= US
"all attempts to verify a sender in a header line deferred";
2466 /*************************************************
2467 * Get RFC 1413 identification *
2468 *************************************************/
2470 /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
2471 the timeout is set to zero, then the query is not done. There may also be lists
2472 of hosts and nets which are exempt. To guard against malefactors sending
2473 non-printing characters which could, for example, disrupt a message's headers,
2474 make sure the string consists of printing characters only.
2477 port the port to connect to; usually this is IDENT_PORT (113), but when
2478 running in the test harness with -bh a different value is used.
2482 Side effect: any received ident value is put in sender_ident (NULL otherwise)
2486 verify_get_ident(int port
)
2488 int sock
, host_af
, qlen
;
2489 int received_sender_port
, received_interface_port
, n
;
2491 uschar buffer
[2048];
2493 /* Default is no ident. Check whether we want to do an ident check for this
2496 sender_ident
= NULL
;
2497 if (rfc1413_query_timeout
<= 0 || verify_check_host(&rfc1413_hosts
) != OK
)
2500 DEBUG(D_ident
) debug_printf("doing ident callback\n");
2502 /* Set up a connection to the ident port of the remote host. Bind the local end
2503 to the incoming interface address. If the sender host address is an IPv6
2504 address, the incoming interface address will also be IPv6. */
2506 host_af
= (Ustrchr(sender_host_address
, ':') == NULL
)? AF_INET
: AF_INET6
;
2507 sock
= ip_socket(SOCK_STREAM
, host_af
);
2508 if (sock
< 0) return;
2510 if (ip_bind(sock
, host_af
, interface_address
, 0) < 0)
2512 DEBUG(D_ident
) debug_printf("bind socket for ident failed: %s\n",
2517 if (ip_connect(sock
, host_af
, sender_host_address
, port
, rfc1413_query_timeout
)
2520 if (errno
== ETIMEDOUT
&& (log_extra_selector
& LX_ident_timeout
) != 0)
2522 log_write(0, LOG_MAIN
, "ident connection to %s timed out",
2523 sender_host_address
);
2527 DEBUG(D_ident
) debug_printf("ident connection to %s failed: %s\n",
2528 sender_host_address
, strerror(errno
));
2533 /* Construct and send the query. */
2535 sprintf(CS buffer
, "%d , %d\r\n", sender_host_port
, interface_port
);
2536 qlen
= Ustrlen(buffer
);
2537 if (send(sock
, buffer
, qlen
, 0) < 0)
2539 DEBUG(D_ident
) debug_printf("ident send failed: %s\n", strerror(errno
));
2543 /* Read a response line. We put it into the rest of the buffer, using several
2544 recv() calls if necessary. */
2552 int size
= sizeof(buffer
) - (p
- buffer
);
2554 if (size
<= 0) goto END_OFF
; /* Buffer filled without seeing \n. */
2555 count
= ip_recv(sock
, p
, size
, rfc1413_query_timeout
);
2556 if (count
<= 0) goto END_OFF
; /* Read error or EOF */
2558 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
2559 generous, and accept a plain \n terminator as well. The only illegal
2562 for (pp
= p
; pp
< p
+ count
; pp
++)
2564 if (*pp
== 0) goto END_OFF
; /* Zero octet not allowed */
2567 if (pp
[-1] == '\r') pp
--;
2569 goto GOT_DATA
; /* Break out of both loops */
2573 /* Reached the end of the data without finding \n. Let the loop continue to
2574 read some more, if there is room. */
2581 /* We have received a line of data. Check it carefully. It must start with the
2582 same two port numbers that we sent, followed by data as defined by the RFC. For
2585 12345 , 25 : USERID : UNIX :root
2587 However, the amount of white space may be different to what we sent. In the
2588 "osname" field there may be several sub-fields, comma separated. The data we
2589 actually want to save follows the third colon. Some systems put leading spaces
2590 in it - we discard those. */
2592 if (sscanf(CS buffer
+ qlen
, "%d , %d%n", &received_sender_port
,
2593 &received_interface_port
, &n
) != 2 ||
2594 received_sender_port
!= sender_host_port
||
2595 received_interface_port
!= interface_port
)
2598 p
= buffer
+ qlen
+ n
;
2599 while(isspace(*p
)) p
++;
2600 if (*p
++ != ':') goto END_OFF
;
2601 while(isspace(*p
)) p
++;
2602 if (Ustrncmp(p
, "USERID", 6) != 0) goto END_OFF
;
2604 while(isspace(*p
)) p
++;
2605 if (*p
++ != ':') goto END_OFF
;
2606 while (*p
!= 0 && *p
!= ':') p
++;
2607 if (*p
++ == 0) goto END_OFF
;
2608 while(isspace(*p
)) p
++;
2609 if (*p
== 0) goto END_OFF
;
2611 /* The rest of the line is the data we want. We turn it into printing
2612 characters when we save it, so that it cannot mess up the format of any logging
2613 or Received: lines into which it gets inserted. We keep a maximum of 127
2616 sender_ident
= string_printing(string_copyn(p
, 127));
2617 DEBUG(D_ident
) debug_printf("sender_ident = %s\n", sender_ident
);
2627 /*************************************************
2628 * Match host to a single host-list item *
2629 *************************************************/
2631 /* This function compares a host (name or address) against a single item
2632 from a host list. The host name gets looked up if it is needed and is not
2633 already known. The function is called from verify_check_this_host() via
2634 match_check_list(), which is why most of its arguments are in a single block.
2637 arg the argument block (see below)
2638 ss the host-list item
2639 valueptr where to pass back looked up data, or NULL
2640 error for error message when returning ERROR
2643 host_name (a) the host name, or
2644 (b) NULL, implying use sender_host_name and
2645 sender_host_aliases, looking them up if required, or
2646 (c) the empty string, meaning that only IP address matches
2648 host_address the host address
2649 host_ipv4 the IPv4 address taken from an IPv6 one
2653 DEFER lookup deferred
2654 ERROR (a) failed to find the host name or IP address, or
2655 (b) unknown lookup type specified, or
2656 (c) host name encountered when only IP addresses are
2661 check_host(void *arg
, uschar
*ss
, uschar
**valueptr
, uschar
**error
)
2663 check_host_block
*cb
= (check_host_block
*)arg
;
2666 BOOL iplookup
= FALSE
;
2667 BOOL isquery
= FALSE
;
2668 BOOL isiponly
= cb
->host_name
!= NULL
&& cb
->host_name
[0] == 0;
2673 /* Optimize for the special case when the pattern is "*". */
2675 if (*ss
== '*' && ss
[1] == 0) return OK
;
2677 /* If the pattern is empty, it matches only in the case when there is no host -
2678 this can occur in ACL checking for SMTP input using the -bs option. In this
2679 situation, the host address is the empty string. */
2681 if (cb
->host_address
[0] == 0) return (*ss
== 0)? OK
: FAIL
;
2682 if (*ss
== 0) return FAIL
;
2684 /* If the pattern is precisely "@" then match against the primary host name,
2685 provided that host name matching is permitted; if it's "@[]" match against the
2686 local host's IP addresses. */
2692 if (isiponly
) return ERROR
;
2693 ss
= primary_hostname
;
2695 else if (Ustrcmp(ss
, "@[]") == 0)
2697 ip_address_item
*ip
;
2698 for (ip
= host_find_interfaces(); ip
!= NULL
; ip
= ip
->next
)
2699 if (Ustrcmp(ip
->address
, cb
->host_address
) == 0) return OK
;
2704 /* If the pattern is an IP address, optionally followed by a bitmask count, do
2705 a (possibly masked) comparision with the current IP address. */
2707 if (string_is_ip_address(ss
, &maskoffset
) != 0)
2708 return (host_is_in_net(cb
->host_address
, ss
, maskoffset
)? OK
: FAIL
);
2710 /* The pattern is not an IP address. A common error that people make is to omit
2711 one component of an IPv4 address, either by accident, or believing that, for
2712 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,
2713 which it isn't. (Those applications that do accept 1.2.3 as an IP address
2714 interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
2715 ancient specification.) To aid in debugging these cases, we give a specific
2716 error if the pattern contains only digits and dots or contains a slash preceded
2717 only by digits and dots (a slash at the start indicates a file name and of
2718 course slashes may be present in lookups, but not preceded only by digits and
2721 for (t
= ss
; isdigit(*t
) || *t
== '.'; t
++);
2722 if (*t
== 0 || (*t
== '/' && t
!= ss
))
2724 *error
= US
"malformed IPv4 address or address mask";
2728 /* See if there is a semicolon in the pattern */
2730 semicolon
= Ustrchr(ss
, ';');
2732 /* If we are doing an IP address only match, then all lookups must be IP
2733 address lookups, even if there is no "net-". */
2737 iplookup
= semicolon
!= NULL
;
2740 /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
2741 a lookup on a masked IP network, in textual form. We obey this code even if we
2742 have already set iplookup, so as to skip over the "net-" prefix and to set the
2743 mask length. The net- stuff really only applies to single-key lookups where the
2744 key is implicit. For query-style lookups the key is specified in the query.
2745 From release 4.30, the use of net- for query style is no longer needed, but we
2746 retain it for backward compatibility. */
2748 if (Ustrncmp(ss
, "net", 3) == 0 && semicolon
!= NULL
)
2751 for (t
= ss
+ 3; isdigit(*t
); t
++) mlen
= mlen
* 10 + *t
- '0';
2752 if (mlen
== 0 && t
== ss
+3) mlen
= -1; /* No mask supplied */
2753 iplookup
= (*t
++ == '-');
2757 /* Do the IP address lookup if that is indeed what we have */
2765 uschar
*filename
, *key
, *result
;
2768 /* Find the search type */
2770 search_type
= search_findtype(t
, semicolon
- t
);
2772 if (search_type
< 0) log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "%s",
2773 search_error_message
);
2775 /* Adjust parameters for the type of lookup. For a query-style lookup, there
2776 is no file name, and the "key" is just the query. For query-style with a file
2777 name, we have to fish the file off the start of the query. For a single-key
2778 lookup, the key is the current IP address, masked appropriately, and
2779 reconverted to text form, with the mask appended. For IPv6 addresses, specify
2780 dot separators instead of colons, except when the lookup type is "iplsearch".
2783 if (mac_islookup(search_type
, lookup_absfilequery
))
2785 filename
= semicolon
+ 1;
2787 while (*key
!= 0 && !isspace(*key
)) key
++;
2788 filename
= string_copyn(filename
, key
- filename
);
2789 while (isspace(*key
)) key
++;
2791 else if (mac_islookup(search_type
, lookup_querystyle
))
2794 key
= semicolon
+ 1;
2796 else /* Single-key style */
2798 int sep
= (Ustrcmp(lookup_list
[search_type
]->name
, "iplsearch") == 0)?
2800 insize
= host_aton(cb
->host_address
, incoming
);
2801 host_mask(insize
, incoming
, mlen
);
2802 (void)host_nmtoa(insize
, incoming
, mlen
, buffer
, sep
);
2804 filename
= semicolon
+ 1;
2807 /* Now do the actual lookup; note that there is no search_close() because
2808 of the caching arrangements. */
2810 handle
= search_open(filename
, search_type
, 0, NULL
, NULL
);
2811 if (handle
== NULL
) log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "%s",
2812 search_error_message
);
2813 result
= search_find(handle
, filename
, key
, -1, NULL
, 0, 0, NULL
);
2814 if (valueptr
!= NULL
) *valueptr
= result
;
2815 return (result
!= NULL
)? OK
: search_find_defer
? DEFER
: FAIL
;
2818 /* The pattern is not an IP address or network reference of any kind. That is,
2819 it is a host name pattern. If this is an IP only match, there's an error in the
2824 *error
= US
"cannot match host name in match_ip list";
2828 /* Check the characters of the pattern to see if they comprise only letters,
2829 digits, full stops, and hyphens (the constituents of domain names). Allow
2830 underscores, as they are all too commonly found. Sigh. Also, if
2831 allow_utf8_domains is set, allow top-bit characters. */
2833 for (t
= ss
; *t
!= 0; t
++)
2834 if (!isalnum(*t
) && *t
!= '.' && *t
!= '-' && *t
!= '_' &&
2835 (!allow_utf8_domains
|| *t
< 128)) break;
2837 /* If the pattern is a complete domain name, with no fancy characters, look up
2838 its IP address and match against that. Note that a multi-homed host will add
2839 items to the chain. */
2850 rc
= host_find_byname(&h
, NULL
, HOST_FIND_QUALIFY_SINGLE
, NULL
, FALSE
);
2851 if (rc
== HOST_FOUND
|| rc
== HOST_FOUND_LOCAL
)
2854 for (hh
= &h
; hh
!= NULL
; hh
= hh
->next
)
2856 if (host_is_in_net(hh
->address
, cb
->host_address
, 0)) return OK
;
2860 if (rc
== HOST_FIND_AGAIN
) return DEFER
;
2861 *error
= string_sprintf("failed to find IP address for %s", ss
);
2865 /* Almost all subsequent comparisons require the host name, and can be done
2866 using the general string matching function. When this function is called for
2867 outgoing hosts, the name is always given explicitly. If it is NULL, it means we
2868 must use sender_host_name and its aliases, looking them up if necessary. */
2870 if (cb
->host_name
!= NULL
) /* Explicit host name given */
2871 return match_check_string(cb
->host_name
, ss
, -1, TRUE
, TRUE
, TRUE
,
2874 /* Host name not given; in principle we need the sender host name and its
2875 aliases. However, for query-style lookups, we do not need the name if the
2876 query does not contain $sender_host_name. From release 4.23, a reference to
2877 $sender_host_name causes it to be looked up, so we don't need to do the lookup
2880 if ((semicolon
= Ustrchr(ss
, ';')) != NULL
)
2883 int partial
, affixlen
, starflags
, id
;
2886 id
= search_findtype_partial(ss
, &partial
, &affix
, &affixlen
, &starflags
);
2889 if (id
< 0) /* Unknown lookup type */
2891 log_write(0, LOG_MAIN
|LOG_PANIC
, "%s in host list item \"%s\"",
2892 search_error_message
, ss
);
2895 isquery
= mac_islookup(id
, lookup_querystyle
|lookup_absfilequery
);
2900 switch(match_check_string(US
"", ss
, -1, TRUE
, TRUE
, TRUE
, valueptr
))
2903 case DEFER
: return DEFER
;
2904 default: return FAIL
;
2908 /* Not a query-style lookup; must ensure the host name is present, and then we
2909 do a check on the name and all its aliases. */
2911 if (sender_host_name
== NULL
)
2913 HDEBUG(D_host_lookup
)
2914 debug_printf("sender host name required, to match against %s\n", ss
);
2915 if (host_lookup_failed
|| host_name_lookup() != OK
)
2917 *error
= string_sprintf("failed to find host name for %s",
2918 sender_host_address
);;
2921 host_build_sender_fullhost();
2924 /* Match on the sender host name, using the general matching function */
2926 switch(match_check_string(sender_host_name
, ss
, -1, TRUE
, TRUE
, TRUE
,
2930 case DEFER
: return DEFER
;
2933 /* If there are aliases, try matching on them. */
2935 aliases
= sender_host_aliases
;
2936 while (*aliases
!= NULL
)
2938 switch(match_check_string(*aliases
++, ss
, -1, TRUE
, TRUE
, TRUE
, valueptr
))
2941 case DEFER
: return DEFER
;
2950 /*************************************************
2951 * Check a specific host matches a host list *
2952 *************************************************/
2954 /* This function is passed a host list containing items in a number of
2955 different formats and the identity of a host. Its job is to determine whether
2956 the given host is in the set of hosts defined by the list. The host name is
2957 passed as a pointer so that it can be looked up if needed and not already
2958 known. This is commonly the case when called from verify_check_host() to check
2959 an incoming connection. When called from elsewhere the host name should usually
2962 This function is now just a front end to match_check_list(), which runs common
2963 code for scanning a list. We pass it the check_host() function to perform a
2967 listptr pointer to the host list
2968 cache_bits pointer to cache for named lists, or NULL
2969 host_name the host name or NULL, implying use sender_host_name and
2970 sender_host_aliases, looking them up if required
2971 host_address the IP address
2972 valueptr if not NULL, data from a lookup is passed back here
2974 Returns: OK if the host is in the defined set
2975 FAIL if the host is not in the defined set,
2976 DEFER if a data lookup deferred (not a host lookup)
2978 If the host name was needed in order to make a comparison, and could not be
2979 determined from the IP address, the result is FAIL unless the item
2980 "+allow_unknown" was met earlier in the list, in which case OK is returned. */
2983 verify_check_this_host(uschar
**listptr
, unsigned int *cache_bits
,
2984 uschar
*host_name
, uschar
*host_address
, uschar
**valueptr
)
2987 unsigned int *local_cache_bits
= cache_bits
;
2988 uschar
*save_host_address
= deliver_host_address
;
2989 check_host_block cb
;
2990 cb
.host_name
= host_name
;
2991 cb
.host_address
= host_address
;
2993 if (valueptr
!= NULL
) *valueptr
= NULL
;
2995 /* If the host address starts off ::ffff: it is an IPv6 address in
2996 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2999 cb
.host_ipv4
= (Ustrncmp(host_address
, "::ffff:", 7) == 0)?
3000 host_address
+ 7 : host_address
;
3002 /* During the running of the check, put the IP address into $host_address. In
3003 the case of calls from the smtp transport, it will already be there. However,
3004 in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
3005 the safe side, any existing setting is preserved, though as I write this
3006 (November 2004) I can't see any cases where it is actually needed. */
3008 deliver_host_address
= host_address
;
3009 rc
= match_check_list(
3010 listptr
, /* the list */
3011 0, /* separator character */
3012 &hostlist_anchor
, /* anchor pointer */
3013 &local_cache_bits
, /* cache pointer */
3014 check_host
, /* function for testing */
3015 &cb
, /* argument for function */
3016 MCL_HOST
, /* type of check */
3017 (host_address
== sender_host_address
)?
3018 US
"host" : host_address
, /* text for debugging */
3019 valueptr
); /* where to pass back data */
3020 deliver_host_address
= save_host_address
;
3027 /*************************************************
3028 * Check the remote host matches a list *
3029 *************************************************/
3031 /* This is a front end to verify_check_this_host(), created because checking
3032 the remote host is a common occurrence. With luck, a good compiler will spot
3033 the tail recursion and optimize it. If there's no host address, this is
3034 command-line SMTP input - check against an empty string for the address.
3037 listptr pointer to the host list
3039 Returns: the yield of verify_check_this_host(),
3040 i.e. OK, FAIL, or DEFER
3044 verify_check_host(uschar
**listptr
)
3046 return verify_check_this_host(listptr
, sender_host_cache
, NULL
,
3047 (sender_host_address
== NULL
)? US
"" : sender_host_address
, NULL
);
3054 /*************************************************
3055 * Invert an IP address *
3056 *************************************************/
3058 /* Originally just used for DNS xBL lists, now also used for the
3059 reverse_ip expansion operator.
3062 buffer where to put the answer
3063 address the address to invert
3067 invert_address(uschar
*buffer
, uschar
*address
)
3070 uschar
*bptr
= buffer
;
3072 /* If this is an IPv4 address mapped into IPv6 format, adjust the pointer
3073 to the IPv4 part only. */
3075 if (Ustrncmp(address
, "::ffff:", 7) == 0) address
+= 7;
3077 /* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is
3080 if (host_aton(address
, bin
) == 1)
3084 for (i
= 0; i
< 4; i
++)
3086 sprintf(CS bptr
, "%d.", x
& 255);
3087 while (*bptr
) bptr
++;
3092 /* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses
3093 in any DNS black lists, and the format in which they will be looked up is
3094 unknown. This is just a guess. */
3100 for (j
= 3; j
>= 0; j
--)
3103 for (i
= 0; i
< 8; i
++)
3105 sprintf(CS bptr
, "%x.", x
& 15);
3106 while (*bptr
) bptr
++;
3113 /* Remove trailing period -- this is needed so that both arbitrary
3114 dnsbl keydomains and inverted addresses may be combined with the
3115 same format string, "%s.%s" */
3122 /*************************************************
3123 * Perform a single dnsbl lookup *
3124 *************************************************/
3126 /* This function is called from verify_check_dnsbl() below. It is also called
3127 recursively from within itself when domain and domain_txt are different
3128 pointers, in order to get the TXT record from the alternate domain.
3131 domain the outer dnsbl domain
3132 domain_txt alternate domain to lookup TXT record on success; when the
3133 same domain is to be used, domain_txt == domain (that is,
3134 the pointers must be identical, not just the text)
3135 keydomain the current keydomain (for debug message)
3136 prepend subdomain to lookup (like keydomain, but
3137 reversed if IP address)
3138 iplist the list of matching IP addresses, or NULL for "any"
3139 bitmask true if bitmask matching is wanted
3140 match_type condition for 'succeed' result
3141 0 => Any RR in iplist (=)
3142 1 => No RR in iplist (!=)
3143 2 => All RRs in iplist (==)
3144 3 => Some RRs not in iplist (!==)
3145 the two bits are defined as MT_NOT and MT_ALL
3146 defer_return what to return for a defer
3148 Returns: OK if lookup succeeded
3153 one_check_dnsbl(uschar
*domain
, uschar
*domain_txt
, uschar
*keydomain
,
3154 uschar
*prepend
, uschar
*iplist
, BOOL bitmask
, int match_type
,
3160 dnsbl_cache_block
*cb
;
3161 int old_pool
= store_pool
;
3162 uschar query
[256]; /* DNS domain max length */
3164 /* Construct the specific query domainname */
3166 if (!string_format(query
, sizeof(query
), "%s.%s", prepend
, domain
))
3168 log_write(0, LOG_MAIN
|LOG_PANIC
, "dnslist query is too long "
3169 "(ignored): %s...", query
);
3173 /* Look for this query in the cache. */
3175 t
= tree_search(dnsbl_cache
, query
);
3177 /* If not cached from a previous lookup, we must do a DNS lookup, and
3178 cache the result in permanent memory. */
3182 store_pool
= POOL_PERM
;
3184 /* Set up a tree entry to cache the lookup */
3186 t
= store_get(sizeof(tree_node
) + Ustrlen(query
));
3187 Ustrcpy(t
->name
, query
);
3188 t
->data
.ptr
= cb
= store_get(sizeof(dnsbl_cache_block
));
3189 (void)tree_insertnode(&dnsbl_cache
, t
);
3191 /* Do the DNS loopup . */
3193 HDEBUG(D_dnsbl
) debug_printf("new DNS lookup for %s\n", query
);
3194 cb
->rc
= dns_basic_lookup(&dnsa
, query
, T_A
);
3195 cb
->text_set
= FALSE
;
3199 /* If the lookup succeeded, cache the RHS address. The code allows for
3200 more than one address - this was for complete generality and the possible
3201 use of A6 records. However, A6 records have been reduced to experimental
3202 status (August 2001) and may die out. So they may never get used at all,
3203 let alone in dnsbl records. However, leave the code here, just in case.
3205 Quite apart from one A6 RR generating multiple addresses, there are DNS
3206 lists that return more than one A record, so we must handle multiple
3207 addresses generated in that way as well. */
3209 if (cb
->rc
== DNS_SUCCEED
)
3212 dns_address
**addrp
= &(cb
->rhs
);
3213 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
3215 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
3217 if (rr
->type
== T_A
)
3219 dns_address
*da
= dns_address_from_rr(&dnsa
, rr
);
3223 while (da
->next
!= NULL
) da
= da
->next
;
3224 addrp
= &(da
->next
);
3229 /* If we didn't find any A records, change the return code. This can
3230 happen when there is a CNAME record but there are no A records for what
3233 if (cb
->rhs
== NULL
) cb
->rc
= DNS_NODATA
;
3236 store_pool
= old_pool
;
3239 /* Previous lookup was cached */
3243 HDEBUG(D_dnsbl
) debug_printf("using result of previous DNS lookup\n");
3247 /* We now have the result of the DNS lookup, either newly done, or cached
3248 from a previous call. If the lookup succeeded, check against the address
3249 list if there is one. This may be a positive equality list (introduced by
3250 "="), a negative equality list (introduced by "!="), a positive bitmask
3251 list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/
3253 if (cb
->rc
== DNS_SUCCEED
)
3255 dns_address
*da
= NULL
;
3256 uschar
*addlist
= cb
->rhs
->address
;
3258 /* For A and AAAA records, there may be multiple addresses from multiple
3259 records. For A6 records (currently not expected to be used) there may be
3260 multiple addresses from a single record. */
3262 for (da
= cb
->rhs
->next
; da
!= NULL
; da
= da
->next
)
3263 addlist
= string_sprintf("%s, %s", addlist
, da
->address
);
3265 HDEBUG(D_dnsbl
) debug_printf("DNS lookup for %s succeeded (yielding %s)\n",
3268 /* Address list check; this can be either for equality, or via a bitmask.
3269 In the latter case, all the bits must match. */
3273 for (da
= cb
->rhs
; da
!= NULL
; da
= da
->next
)
3277 uschar
*ptr
= iplist
;
3280 /* Handle exact matching */
3284 while ((res
= string_nextinlist(&ptr
, &ipsep
, ip
, sizeof(ip
))) != NULL
)
3286 if (Ustrcmp(CS da
->address
, ip
) == 0) break;
3290 /* Handle bitmask matching */
3297 /* At present, all known DNS blocking lists use A records, with
3298 IPv4 addresses on the RHS encoding the information they return. I
3299 wonder if this will linger on as the last vestige of IPv4 when IPv6
3300 is ubiquitous? Anyway, for now we use paranoia code to completely
3301 ignore IPv6 addresses. The default mask is 0, which always matches.
3302 We change this only for IPv4 addresses in the list. */
3304 if (host_aton(da
->address
, address
) == 1) mask
= address
[0];
3306 /* Scan the returned addresses, skipping any that are IPv6 */
3308 while ((res
= string_nextinlist(&ptr
, &ipsep
, ip
, sizeof(ip
))) != NULL
)
3310 if (host_aton(ip
, address
) != 1) continue;
3311 if ((address
[0] & mask
) == address
[0]) break;
3317 (a) An IP address in an any ('=') list matched, or
3318 (b) No IP address in an all ('==') list matched
3320 then we're done searching. */
3322 if (((match_type
& MT_ALL
) != 0) == (res
== NULL
)) break;
3325 /* If da == NULL, either
3327 (a) No IP address in an any ('=') list matched, or
3328 (b) An IP address in an all ('==') list didn't match
3330 so behave as if the DNSBL lookup had not succeeded, i.e. the host is not on
3333 if ((match_type
== MT_NOT
|| match_type
== MT_ALL
) != (da
== NULL
))
3341 res
= US
"was no match";
3344 res
= US
"was an exclude match";
3347 res
= US
"was an IP address that did not match";
3350 res
= US
"were no IP addresses that did not match";
3353 debug_printf("=> but we are not accepting this block class because\n");
3354 debug_printf("=> there %s for %s%c%s\n",
3356 ((match_type
& MT_ALL
) == 0)? "" : "=",
3357 bitmask
? '&' : '=', iplist
);
3363 /* Either there was no IP list, or the record matched, implying that the
3364 domain is on the list. We now want to find a corresponding TXT record. If an
3365 alternate domain is specified for the TXT record, call this function
3366 recursively to look that up; this has the side effect of re-checking that
3367 there is indeed an A record at the alternate domain. */
3369 if (domain_txt
!= domain
)
3370 return one_check_dnsbl(domain_txt
, domain_txt
, keydomain
, prepend
, NULL
,
3371 FALSE
, match_type
, defer_return
);
3373 /* If there is no alternate domain, look up a TXT record in the main domain
3374 if it has not previously been cached. */
3378 cb
->text_set
= TRUE
;
3379 if (dns_basic_lookup(&dnsa
, query
, T_TXT
) == DNS_SUCCEED
)
3382 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
3384 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
3385 if (rr
->type
== T_TXT
) break;
3388 int len
= (rr
->data
)[0];
3389 if (len
> 511) len
= 127;
3390 store_pool
= POOL_PERM
;
3391 cb
->text
= string_sprintf("%.*s", len
, (const uschar
*)(rr
->data
+1));
3392 store_pool
= old_pool
;
3397 dnslist_value
= addlist
;
3398 dnslist_text
= cb
->text
;
3402 /* There was a problem with the DNS lookup */
3404 if (cb
->rc
!= DNS_NOMATCH
&& cb
->rc
!= DNS_NODATA
)
3406 log_write(L_dnslist_defer
, LOG_MAIN
,
3407 "DNS list lookup defer (probably timeout) for %s: %s", query
,
3408 (defer_return
== OK
)? US
"assumed in list" :
3409 (defer_return
== FAIL
)? US
"assumed not in list" :
3410 US
"returned DEFER");
3411 return defer_return
;
3414 /* No entry was found in the DNS; continue for next domain */
3418 debug_printf("DNS lookup for %s failed\n", query
);
3419 debug_printf("=> that means %s is not listed at %s\n",
3429 /*************************************************
3430 * Check host against DNS black lists *
3431 *************************************************/
3433 /* This function runs checks against a list of DNS black lists, until one
3434 matches. Each item on the list can be of the form
3436 domain=ip-address/key
3438 The domain is the right-most domain that is used for the query, for example,
3439 blackholes.mail-abuse.org. If the IP address is present, there is a match only
3440 if the DNS lookup returns a matching IP address. Several addresses may be
3441 given, comma-separated, for example: x.y.z=127.0.0.1,127.0.0.2.
3443 If no key is given, what is looked up in the domain is the inverted IP address
3444 of the current client host. If a key is given, it is used to construct the
3445 domain for the lookup. For example:
3447 dsn.rfc-ignorant.org/$sender_address_domain
3449 After finding a match in the DNS, the domain is placed in $dnslist_domain, and
3450 then we check for a TXT record for an error message, and if found, save its
3451 value in $dnslist_text. We also cache everything in a tree, to optimize
3454 The TXT record is normally looked up in the same domain as the A record, but
3455 when many lists are combined in a single DNS domain, this will not be a very
3456 specific message. It is possible to specify a different domain for looking up
3457 TXT records; this is given before the main domain, comma-separated. For
3460 dnslists = http.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.2 : \
3461 socks.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.3
3463 The caching ensures that only one lookup in dnsbl.sorbs.net is done.
3465 Note: an address for testing RBL is 192.203.178.39
3466 Note: an address for testing DUL is 192.203.178.4
3467 Note: a domain for testing RFCI is example.tld.dsn.rfc-ignorant.org
3470 listptr the domain/address/data list
3472 Returns: OK successful lookup (i.e. the address is on the list), or
3473 lookup deferred after +include_unknown
3474 FAIL name not found, or no data found for the given type, or
3475 lookup deferred after +exclude_unknown (default)
3476 DEFER lookup failure, if +defer_unknown was set
3480 verify_check_dnsbl(uschar
**listptr
)
3483 int defer_return
= FAIL
;
3484 uschar
*list
= *listptr
;
3487 uschar buffer
[1024];
3488 uschar revadd
[128]; /* Long enough for IPv6 address */
3490 /* Indicate that the inverted IP address is not yet set up */
3494 /* In case this is the first time the DNS resolver is being used. */
3496 dns_init(FALSE
, FALSE
);
3498 /* Loop through all the domains supplied, until something matches */
3500 while ((domain
= string_nextinlist(&list
, &sep
, buffer
, sizeof(buffer
))) != NULL
)
3503 BOOL bitmask
= FALSE
;
3510 HDEBUG(D_dnsbl
) debug_printf("DNS list check: %s\n", domain
);
3512 /* Deal with special values that change the behaviour on defer */
3514 if (domain
[0] == '+')
3516 if (strcmpic(domain
, US
"+include_unknown") == 0) defer_return
= OK
;
3517 else if (strcmpic(domain
, US
"+exclude_unknown") == 0) defer_return
= FAIL
;
3518 else if (strcmpic(domain
, US
"+defer_unknown") == 0) defer_return
= DEFER
;
3520 log_write(0, LOG_MAIN
|LOG_PANIC
, "unknown item in dnslist (ignored): %s",
3525 /* See if there's explicit data to be looked up */
3527 key
= Ustrchr(domain
, '/');
3528 if (key
!= NULL
) *key
++ = 0;
3530 /* See if there's a list of addresses supplied after the domain name. This is
3531 introduced by an = or a & character; if preceded by = we require all matches
3532 and if preceded by ! we invert the result. */
3534 iplist
= Ustrchr(domain
, '=');
3538 iplist
= Ustrchr(domain
, '&');
3541 if (iplist
!= NULL
) /* Found either = or & */
3543 if (iplist
> domain
&& iplist
[-1] == '!') /* Handle preceding ! */
3545 match_type
|= MT_NOT
;
3549 *iplist
++ = 0; /* Terminate domain, move on */
3551 /* If we found = (bitmask == FALSE), check for == or =& */
3553 if (!bitmask
&& (*iplist
== '=' || *iplist
== '&'))
3555 bitmask
= *iplist
++ == '&';
3556 match_type
|= MT_ALL
;
3560 /* If there is a comma in the domain, it indicates that a second domain for
3561 looking up TXT records is provided, before the main domain. Otherwise we must
3562 set domain_txt == domain. */
3564 domain_txt
= domain
;
3565 comma
= Ustrchr(domain
, ',');
3572 /* Check that what we have left is a sensible domain name. There is no reason
3573 why these domains should in fact use the same syntax as hosts and email
3574 domains, but in practice they seem to. However, there is little point in
3575 actually causing an error here, because that would no doubt hold up incoming
3576 mail. Instead, I'll just log it. */
3578 for (s
= domain
; *s
!= 0; s
++)
3580 if (!isalnum(*s
) && *s
!= '-' && *s
!= '.' && *s
!= '_')
3582 log_write(0, LOG_MAIN
, "dnslists domain \"%s\" contains "
3583 "strange characters - is this right?", domain
);
3588 /* Check the alternate domain if present */
3590 if (domain_txt
!= domain
) for (s
= domain_txt
; *s
!= 0; s
++)
3592 if (!isalnum(*s
) && *s
!= '-' && *s
!= '.' && *s
!= '_')
3594 log_write(0, LOG_MAIN
, "dnslists domain \"%s\" contains "
3595 "strange characters - is this right?", domain_txt
);
3600 /* If there is no key string, construct the query by adding the domain name
3601 onto the inverted host address, and perform a single DNS lookup. */
3605 if (sender_host_address
== NULL
) return FAIL
; /* can never match */
3606 if (revadd
[0] == 0) invert_address(revadd
, sender_host_address
);
3607 rc
= one_check_dnsbl(domain
, domain_txt
, sender_host_address
, revadd
,
3608 iplist
, bitmask
, match_type
, defer_return
);
3611 dnslist_domain
= string_copy(domain_txt
);
3612 dnslist_matched
= string_copy(sender_host_address
);
3613 HDEBUG(D_dnsbl
) debug_printf("=> that means %s is listed at %s\n",
3614 sender_host_address
, dnslist_domain
);
3616 if (rc
!= FAIL
) return rc
; /* OK or DEFER */
3619 /* If there is a key string, it can be a list of domains or IP addresses to
3620 be concatenated with the main domain. */
3627 uschar keybuffer
[256];
3628 uschar keyrevadd
[128];
3630 while ((keydomain
= string_nextinlist(&key
, &keysep
, keybuffer
,
3631 sizeof(keybuffer
))) != NULL
)
3633 uschar
*prepend
= keydomain
;
3635 if (string_is_ip_address(keydomain
, NULL
) != 0)
3637 invert_address(keyrevadd
, keydomain
);
3638 prepend
= keyrevadd
;
3641 rc
= one_check_dnsbl(domain
, domain_txt
, keydomain
, prepend
, iplist
,
3642 bitmask
, match_type
, defer_return
);
3646 dnslist_domain
= string_copy(domain_txt
);
3647 dnslist_matched
= string_copy(keydomain
);
3648 HDEBUG(D_dnsbl
) debug_printf("=> that means %s is listed at %s\n",
3649 keydomain
, dnslist_domain
);
3653 /* If the lookup deferred, remember this fact. We keep trying the rest
3654 of the list to see if we get a useful result, and if we don't, we return
3655 DEFER at the end. */
3657 if (rc
== DEFER
) defer
= TRUE
;
3658 } /* continue with next keystring domain/address */
3660 if (defer
) return DEFER
;
3662 } /* continue with next dnsdb outer domain */
3667 /* End of verify.c */