1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
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
)
703 if (addr
->transport
->filter_command
)
705 cutthrough_delivery
= FALSE
;
706 HDEBUG(D_acl
|D_v
) debug_printf("Cutthrough cancelled by presence of transport filter\n");
711 cutthrough_delivery
= FALSE
;
712 HDEBUG(D_acl
|D_v
) debug_printf("Cutthrough cancelled by presence of DKIM signing\n");
721 /* Clear down of the TLS, SMTP and TCP layers on error is handled below. */
724 /* Failure to accept HELO is cached; this blocks the whole domain for all
725 senders. I/O errors and defer responses are not cached. */
729 *failure_ptr
= US
"mail"; /* At or before MAIL */
730 if (errno
== 0 && responsebuffer
[0] == '5')
732 setflag(addr
, af_verify_nsfail
);
733 new_domain_record
.result
= ccache_reject
;
737 /* If we haven't authenticated, but are required to, give up. */
740 else done
= smtp_auth(responsebuffer
, sizeof(responsebuffer
),
741 addr
, host
, ob
, esmtp
, &inblock
, &outblock
) == OK
&&
743 /* Copy AUTH info for logging */
744 ( (addr
->authenticator
= client_authenticator
),
745 (addr
->auth_id
= client_authenticated_id
),
747 /* Build a mail-AUTH string (re-using responsebuffer for convenience */
748 !smtp_mail_auth_str(responsebuffer
, sizeof(responsebuffer
), addr
, ob
)
751 ( (addr
->auth_sndr
= client_authenticated_sender
),
753 /* Send the MAIL command */
754 (smtp_write_command(&outblock
, FALSE
, "MAIL FROM:<%s>%s\r\n",
755 from_address
, responsebuffer
) >= 0)
758 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
761 /* If the host does not accept MAIL FROM:<>, arrange to cache this
762 information, but again, don't record anything for an I/O error or a defer. Do
763 not cache rejections of MAIL when a non-empty sender has been used, because
764 that blocks the whole domain for all senders. */
768 *failure_ptr
= US
"mail"; /* At or before MAIL */
769 if (errno
== 0 && responsebuffer
[0] == '5')
771 setflag(addr
, af_verify_nsfail
);
772 if (from_address
[0] == 0)
773 new_domain_record
.result
= ccache_reject_mfnull
;
777 /* Otherwise, proceed to check a "random" address (if required), then the
778 given address, and the postmaster address (if required). Between each check,
779 issue RSET, because some servers accept only one recipient after MAIL
782 Before doing this, set the result in the domain cache record to "accept",
783 unless its previous value was ccache_reject_mfnull. In that case, the domain
784 rejects MAIL FROM:<> and we want to continue to remember that. When that is
785 the case, we have got here only in the case of a recipient verification with
786 a non-null sender. */
790 new_domain_record
.result
=
791 (old_domain_cache_result
== ccache_reject_mfnull
)?
792 ccache_reject_mfnull
: ccache_accept
;
794 /* Do the random local part check first */
796 if (random_local_part
!= NULL
)
798 uschar randombuffer
[1024];
800 smtp_write_command(&outblock
, FALSE
,
801 "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part
,
802 addr
->domain
) >= 0 &&
803 smtp_read_response(&inblock
, randombuffer
,
804 sizeof(randombuffer
), '2', callout
);
806 /* Remember when we last did a random test */
808 new_domain_record
.random_stamp
= time(NULL
);
810 /* If accepted, we aren't going to do any further tests below. */
814 new_domain_record
.random_result
= ccache_accept
;
817 /* Otherwise, cache a real negative response, and get back to the right
818 state to send RCPT. Unless there's some problem such as a dropped
819 connection, we expect to succeed, because the commands succeeded above. */
823 if (randombuffer
[0] == '5')
824 new_domain_record
.random_result
= ccache_reject
;
827 smtp_write_command(&outblock
, FALSE
, "RSET\r\n") >= 0 &&
828 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
831 smtp_write_command(&outblock
, FALSE
, "MAIL FROM:<%s>\r\n",
832 from_address
) >= 0 &&
833 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
836 else done
= FALSE
; /* Some timeout/connection problem */
839 /* If the host is accepting all local parts, as determined by the "random"
840 check, we don't need to waste time doing any further checking. */
842 if (new_domain_record
.random_result
!= ccache_accept
&& done
)
844 /* Get the rcpt_include_affixes flag from the transport if there is one,
845 but assume FALSE if there is not. */
848 smtp_write_command(&outblock
, FALSE
, "RCPT TO:<%.1000s>\r\n",
849 transport_rcpt_address(addr
,
850 (addr
->transport
== NULL
)? FALSE
:
851 addr
->transport
->rcpt_include_affixes
)) >= 0 &&
852 smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
),
856 new_address_record
.result
= ccache_accept
;
857 else if (errno
== 0 && responsebuffer
[0] == '5')
859 *failure_ptr
= US
"recipient";
860 new_address_record
.result
= ccache_reject
;
863 /* Do postmaster check if requested; if a full check is required, we
864 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
866 if (done
&& pm_mailfrom
!= NULL
)
868 /*XXX not suitable for cutthrough - sequencing problems */
869 cutthrough_delivery
= FALSE
;
870 HDEBUG(D_acl
|D_v
) debug_printf("Cutthrough cancelled by presence of postmaster verify\n");
873 smtp_write_command(&outblock
, FALSE
, "RSET\r\n") >= 0 &&
874 smtp_read_response(&inblock
, responsebuffer
,
875 sizeof(responsebuffer
), '2', callout
) &&
877 smtp_write_command(&outblock
, FALSE
,
878 "MAIL FROM:<%s>\r\n", pm_mailfrom
) >= 0 &&
879 smtp_read_response(&inblock
, responsebuffer
,
880 sizeof(responsebuffer
), '2', callout
) &&
882 /* First try using the current domain */
885 smtp_write_command(&outblock
, FALSE
,
886 "RCPT TO:<postmaster@%.1000s>\r\n", addr
->domain
) >= 0 &&
887 smtp_read_response(&inblock
, responsebuffer
,
888 sizeof(responsebuffer
), '2', callout
)
893 /* If that doesn't work, and a full check is requested,
894 try without the domain. */
897 (options
& vopt_callout_fullpm
) != 0 &&
898 smtp_write_command(&outblock
, FALSE
,
899 "RCPT TO:<postmaster>\r\n") >= 0 &&
900 smtp_read_response(&inblock
, responsebuffer
,
901 sizeof(responsebuffer
), '2', callout
)
904 /* Sort out the cache record */
906 new_domain_record
.postmaster_stamp
= time(NULL
);
909 new_domain_record
.postmaster_result
= ccache_accept
;
910 else if (errno
== 0 && responsebuffer
[0] == '5')
912 *failure_ptr
= US
"postmaster";
913 setflag(addr
, af_verify_pmfail
);
914 new_domain_record
.postmaster_result
= ccache_reject
;
917 } /* Random not accepted */
918 } /* MAIL FROM: accepted */
920 /* For any failure of the main check, other than a negative response, we just
921 close the connection and carry on. We can identify a negative response by the
922 fact that errno is zero. For I/O errors it will be non-zero
924 Set up different error texts for logging and for sending back to the caller
925 as an SMTP response. Log in all cases, using a one-line format. For sender
926 callouts, give a full response to the caller, but for recipient callouts,
927 don't give the IP address because this may be an internal host whose identity
928 is not to be widely broadcast. */
932 if (errno
== ETIMEDOUT
)
934 HDEBUG(D_verify
) debug_printf("SMTP timeout\n");
939 if (*responsebuffer
== 0) Ustrcpy(responsebuffer
, US
"connection dropped");
942 string_sprintf("response to \"%s\" from %s [%s] was: %s",
943 big_buffer
, host
->name
, host
->address
,
944 string_printing(responsebuffer
));
946 addr
->user_message
= is_recipient
?
947 string_sprintf("Callout verification failed:\n%s", responsebuffer
)
949 string_sprintf("Called: %s\nSent: %s\nResponse: %s",
950 host
->address
, big_buffer
, responsebuffer
);
952 /* Hard rejection ends the process */
954 if (responsebuffer
[0] == '5') /* Address rejected */
962 /* End the SMTP conversation and close the connection. */
964 /* Cutthrough - on a successfull connect and recipient-verify with use-sender
965 and we have no cutthrough conn so far
966 here is where we want to leave the conn open */
967 if ( cutthrough_delivery
970 && (options
& (vopt_callout_recipsender
|vopt_callout_recippmaster
)) == vopt_callout_recipsender
971 && !random_local_part
976 cutthrough_fd
= outblock
.sock
; /* We assume no buffer in use in the outblock */
977 cutthrough_addr
= *addr
; /* Save the address_item for later logging */
978 cutthrough_addr
.host_used
= store_get(sizeof(host_item
));
979 cutthrough_addr
.host_used
->name
= host
->name
;
980 cutthrough_addr
.host_used
->address
= host
->address
;
981 cutthrough_addr
.host_used
->port
= port
;
983 *(cutthrough_addr
.parent
= store_get(sizeof(address_item
)))= *addr
->parent
;
984 ctblock
.buffer
= ctbuffer
;
985 ctblock
.buffersize
= sizeof(ctbuffer
);
986 ctblock
.ptr
= ctbuffer
;
987 /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */
988 ctblock
.sock
= cutthrough_fd
;
992 /* Ensure no cutthrough on multiple address verifies */
993 if (options
& vopt_callout_recipsender
)
994 cancel_cutthrough_connection("multiple verify calls");
995 if (send_quit
) (void)smtp_write_command(&outblock
, FALSE
, "QUIT\r\n");
998 tls_close(FALSE
, TRUE
);
1000 (void)close(inblock
.sock
);
1003 } /* Loop through all hosts, while !done */
1006 /* If we get here with done == TRUE, a successful callout happened, and yield
1007 will be set OK or FAIL according to the response to the RCPT command.
1008 Otherwise, we looped through the hosts but couldn't complete the business.
1009 However, there may be domain-specific information to cache in both cases.
1011 The value of the result field in the new_domain record is ccache_unknown if
1012 there was an error before or with MAIL FROM:, and errno was not zero,
1013 implying some kind of I/O error. We don't want to write the cache in that case.
1014 Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
1016 if (!callout_no_cache
&& new_domain_record
.result
!= ccache_unknown
)
1018 if ((dbm_file
= dbfn_open(US
"callout", O_RDWR
|O_CREAT
, &dbblock
, FALSE
))
1021 HDEBUG(D_verify
) debug_printf("callout cache: not available\n");
1025 (void)dbfn_write(dbm_file
, addr
->domain
, &new_domain_record
,
1026 (int)sizeof(dbdata_callout_cache
));
1027 HDEBUG(D_verify
) debug_printf("wrote callout cache domain record:\n"
1028 " result=%d postmaster=%d random=%d\n",
1029 new_domain_record
.result
,
1030 new_domain_record
.postmaster_result
,
1031 new_domain_record
.random_result
);
1035 /* If a definite result was obtained for the callout, cache it unless caching
1040 if (!callout_no_cache
&& new_address_record
.result
!= ccache_unknown
)
1042 if (dbm_file
== NULL
)
1043 dbm_file
= dbfn_open(US
"callout", O_RDWR
|O_CREAT
, &dbblock
, FALSE
);
1044 if (dbm_file
== NULL
)
1046 HDEBUG(D_verify
) debug_printf("no callout cache available\n");
1050 (void)dbfn_write(dbm_file
, address_key
, &new_address_record
,
1051 (int)sizeof(dbdata_callout_cache_address
));
1052 HDEBUG(D_verify
) debug_printf("wrote %s callout cache address record\n",
1053 (new_address_record
.result
== ccache_accept
)? "positive" : "negative");
1058 /* Failure to connect to any host, or any response other than 2xx or 5xx is a
1059 temporary error. If there was only one host, and a response was received, leave
1060 it alone if supplying details. Otherwise, give a generic response. */
1064 uschar
*dullmsg
= string_sprintf("Could not complete %s verify callout",
1065 is_recipient
? "recipient" : "sender");
1068 if (host_list
->next
!= NULL
|| addr
->message
== NULL
) addr
->message
= dullmsg
;
1070 addr
->user_message
= (!smtp_return_error_details
)? dullmsg
:
1071 string_sprintf("%s for <%s>.\n"
1072 "The mail server(s) for the domain may be temporarily unreachable, or\n"
1073 "they may be permanently unreachable from this server. In the latter case,\n%s",
1074 dullmsg
, addr
->address
,
1076 "the address will never be accepted."
1078 "you need to change the address or create an MX record for its domain\n"
1079 "if it is supposed to be generally accessible from the Internet.\n"
1080 "Talk to your mail administrator for details.");
1082 /* Force a specific error code */
1084 addr
->basic_errno
= ERRNO_CALLOUTDEFER
;
1087 /* Come here from within the cache-reading code on fast-track exit. */
1090 if (dbm_file
!= NULL
) dbfn_close(dbm_file
);
1096 /* Called after recipient-acl to get a cutthrough connection open when
1097 one was requested and a recipient-verify wasn't subsequently done.
1100 open_cutthrough_connection( address_item
* addr
)
1104 /* Use a recipient-verify-callout to set up the cutthrough connection. */
1105 /* We must use a copy of the address for verification, because it might
1109 HDEBUG(D_acl
) debug_printf("----------- start cutthrough setup ------------\n");
1110 (void) verify_address(&addr2
, NULL
,
1111 vopt_is_recipient
| vopt_callout_recipsender
| vopt_callout_no_cache
,
1112 CUTTHROUGH_CMD_TIMEOUT
, -1, -1,
1114 HDEBUG(D_acl
) debug_printf("----------- end cutthrough setup ------------\n");
1120 /* Send given number of bytes from the buffer */
1122 cutthrough_send(int n
)
1124 if(cutthrough_fd
< 0)
1129 (tls_out
.active
== cutthrough_fd
) ? tls_write(FALSE
, ctblock
.buffer
, n
) :
1131 send(cutthrough_fd
, ctblock
.buffer
, n
, 0) > 0
1134 transport_count
+= n
;
1135 ctblock
.ptr
= ctblock
.buffer
;
1139 HDEBUG(D_transport
|D_acl
) debug_printf("cutthrough_send failed: %s\n", strerror(errno
));
1146 _cutthrough_puts(uschar
* cp
, int n
)
1150 if(ctblock
.ptr
>= ctblock
.buffer
+ctblock
.buffersize
)
1151 if(!cutthrough_send(ctblock
.buffersize
))
1154 *ctblock
.ptr
++ = *cp
++;
1159 /* Buffered output of counted data block. Return boolean success */
1161 cutthrough_puts(uschar
* cp
, int n
)
1163 if (cutthrough_fd
< 0) return TRUE
;
1164 if (_cutthrough_puts(cp
, n
)) return TRUE
;
1165 cancel_cutthrough_connection("transmit failed");
1171 _cutthrough_flush_send( void )
1173 int n
= ctblock
.ptr
-ctblock
.buffer
;
1176 if(!cutthrough_send(n
))
1182 /* Send out any bufferred output. Return boolean success. */
1184 cutthrough_flush_send( void )
1186 if (_cutthrough_flush_send()) return TRUE
;
1187 cancel_cutthrough_connection("transmit failed");
1193 cutthrough_put_nl( void )
1195 return cutthrough_puts(US
"\r\n", 2);
1199 /* Get and check response from cutthrough target */
1201 cutthrough_response(char expect
, uschar
** copy
)
1203 smtp_inblock inblock
;
1204 uschar inbuffer
[4096];
1205 uschar responsebuffer
[4096];
1207 inblock
.buffer
= inbuffer
;
1208 inblock
.buffersize
= sizeof(inbuffer
);
1209 inblock
.ptr
= inbuffer
;
1210 inblock
.ptrend
= inbuffer
;
1211 inblock
.sock
= cutthrough_fd
;
1212 /* this relies on (inblock.sock == tls_out.active) */
1213 if(!smtp_read_response(&inblock
, responsebuffer
, sizeof(responsebuffer
), expect
, CUTTHROUGH_DATA_TIMEOUT
))
1214 cancel_cutthrough_connection("target timeout on read");
1219 *copy
= cp
= string_copy(responsebuffer
);
1220 /* Trim the trailing end of line */
1221 cp
+= Ustrlen(responsebuffer
);
1222 if(cp
> *copy
&& cp
[-1] == '\n') *--cp
= '\0';
1223 if(cp
> *copy
&& cp
[-1] == '\r') *--cp
= '\0';
1226 return responsebuffer
[0];
1230 /* Negotiate dataphase with the cutthrough target, returning success boolean */
1232 cutthrough_predata( void )
1234 if(cutthrough_fd
< 0)
1237 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> DATA\n");
1238 cutthrough_puts(US
"DATA\r\n", 6);
1239 cutthrough_flush_send();
1241 /* Assume nothing buffered. If it was it gets ignored. */
1242 return cutthrough_response('3', NULL
) == '3';
1246 /* Buffered send of headers. Return success boolean. */
1247 /* Expands newlines to wire format (CR,NL). */
1248 /* Also sends header-terminating blank line. */
1250 cutthrough_headers_send( void )
1253 uschar
* cp1
, * cp2
;
1255 if(cutthrough_fd
< 0)
1258 for(h
= header_list
; h
!= NULL
; h
= h
->next
)
1259 if(h
->type
!= htype_old
&& h
->text
!= NULL
)
1260 for (cp1
= h
->text
; *cp1
&& (cp2
= Ustrchr(cp1
, '\n')); cp1
= cp2
+1)
1261 if( !cutthrough_puts(cp1
, cp2
-cp1
)
1262 || !cutthrough_put_nl())
1265 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>>(nl)\n");
1266 return cutthrough_put_nl();
1271 close_cutthrough_connection( const char * why
)
1273 if(cutthrough_fd
>= 0)
1275 /* We could be sending this after a bunch of data, but that is ok as
1276 the only way to cancel the transfer in dataphase is to drop the tcp
1277 conn before the final dot.
1279 ctblock
.ptr
= ctbuffer
;
1280 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> QUIT\n");
1281 _cutthrough_puts(US
"QUIT\r\n", 6); /* avoid recursion */
1282 _cutthrough_flush_send();
1283 /* No wait for response */
1286 tls_close(FALSE
, TRUE
);
1288 (void)close(cutthrough_fd
);
1290 HDEBUG(D_acl
) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why
);
1292 ctblock
.ptr
= ctbuffer
;
1296 cancel_cutthrough_connection( const char * why
)
1298 close_cutthrough_connection(why
);
1299 cutthrough_delivery
= FALSE
;
1305 /* Have senders final-dot. Send one to cutthrough target, and grab the response.
1306 Log an OK response as a transmission.
1307 Close the connection.
1308 Return smtp response-class digit.
1311 cutthrough_finaldot( void )
1313 HDEBUG(D_transport
|D_acl
|D_v
) debug_printf(" SMTP>> .\n");
1315 /* Assume data finshed with new-line */
1316 if(!cutthrough_puts(US
".", 1) || !cutthrough_put_nl() || !cutthrough_flush_send())
1317 return cutthrough_addr
.message
;
1319 switch(cutthrough_response('2', &cutthrough_addr
.message
))
1322 delivery_log(LOG_MAIN
, &cutthrough_addr
, (int)'>', NULL
);
1323 close_cutthrough_connection("delivered");
1327 delivery_log(LOG_MAIN
, &cutthrough_addr
, 0, US
"tmp-reject from cutthrough after DATA:");
1331 delivery_log(LOG_MAIN
|LOG_REJECT
, &cutthrough_addr
, 0, US
"rejected after DATA:");
1337 return cutthrough_addr
.message
;
1342 /*************************************************
1343 * Copy error to toplevel address *
1344 *************************************************/
1346 /* This function is used when a verify fails or defers, to ensure that the
1347 failure or defer information is in the original toplevel address. This applies
1348 when an address is redirected to a single new address, and the failure or
1349 deferral happens to the child address.
1352 vaddr the verify address item
1353 addr the final address item
1356 Returns: the value of YIELD
1360 copy_error(address_item
*vaddr
, address_item
*addr
, int yield
)
1364 vaddr
->message
= addr
->message
;
1365 vaddr
->user_message
= addr
->user_message
;
1366 vaddr
->basic_errno
= addr
->basic_errno
;
1367 vaddr
->more_errno
= addr
->more_errno
;
1368 vaddr
->p
.address_data
= addr
->p
.address_data
;
1369 copyflag(vaddr
, addr
, af_pass_message
);
1377 /**************************************************
1378 * printf that automatically handles TLS if needed *
1379 ***************************************************/
1381 /* This function is used by verify_address() as a substitute for all fprintf()
1382 calls; a direct fprintf() will not produce output in a TLS SMTP session, such
1383 as a response to an EXPN command. smtp_in.c makes smtp_printf available but
1384 that assumes that we always use the smtp_out FILE* when not using TLS or the
1385 ssl buffer when we are. Instead we take a FILE* parameter and check to see if
1386 that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular
1390 f the candidate FILE* to write to
1391 format format string
1392 ... optional arguments
1398 static void PRINTF_FUNCTION(2,3)
1399 respond_printf(FILE *f
, const char *format
, ...)
1403 va_start(ap
, format
);
1404 if (smtp_out
&& (f
== smtp_out
))
1405 smtp_vprintf(format
, ap
);
1407 vfprintf(f
, format
, ap
);
1413 /*************************************************
1414 * Verify an email address *
1415 *************************************************/
1417 /* This function is used both for verification (-bv and at other times) and
1418 address testing (-bt), which is indicated by address_test_mode being set.
1421 vaddr contains the address to verify; the next field in this block
1423 f if not NULL, write the result to this file
1424 options various option bits:
1425 vopt_fake_sender => this sender verify is not for the real
1426 sender (it was verify=sender=xxxx or an address from a
1427 header line) - rewriting must not change sender_address
1428 vopt_is_recipient => this is a recipient address, otherwise
1429 it's a sender address - this affects qualification and
1430 rewriting and messages from callouts
1431 vopt_qualify => qualify an unqualified address; else error
1432 vopt_expn => called from SMTP EXPN command
1433 vopt_success_on_redirect => when a new address is generated
1434 the verification instantly succeeds
1436 These ones are used by do_callout() -- the options variable
1439 vopt_callout_fullpm => if postmaster check, do full one
1440 vopt_callout_no_cache => don't use callout cache
1441 vopt_callout_random => do the "random" thing
1442 vopt_callout_recipsender => use real sender for recipient
1443 vopt_callout_recippmaster => use postmaster for recipient
1445 callout if > 0, specifies that callout is required, and gives timeout
1446 for individual commands
1447 callout_overall if > 0, gives overall timeout for the callout function;
1448 if < 0, a default is used (see do_callout())
1449 callout_connect the connection timeout for callouts
1450 se_mailfrom when callout is requested to verify a sender, use this
1451 in MAIL FROM; NULL => ""
1452 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
1453 thing and use this as the sender address (may be "")
1455 routed if not NULL, set TRUE if routing succeeded, so we can
1456 distinguish between routing failed and callout failed
1458 Returns: OK address verified
1459 FAIL address failed to verify
1460 DEFER can't tell at present
1464 verify_address(address_item
*vaddr
, FILE *f
, int options
, int callout
,
1465 int callout_overall
, int callout_connect
, uschar
*se_mailfrom
,
1466 uschar
*pm_mailfrom
, BOOL
*routed
)
1469 BOOL full_info
= (f
== NULL
)? FALSE
: (debug_selector
!= 0);
1470 BOOL is_recipient
= (options
& vopt_is_recipient
) != 0;
1471 BOOL expn
= (options
& vopt_expn
) != 0;
1472 BOOL success_on_redirect
= (options
& vopt_success_on_redirect
) != 0;
1475 int verify_type
= expn
? v_expn
:
1476 address_test_mode
? v_none
:
1477 is_recipient
? v_recipient
: v_sender
;
1478 address_item
*addr_list
;
1479 address_item
*addr_new
= NULL
;
1480 address_item
*addr_remote
= NULL
;
1481 address_item
*addr_local
= NULL
;
1482 address_item
*addr_succeed
= NULL
;
1483 uschar
**failure_ptr
= is_recipient
?
1484 &recipient_verify_failure
: &sender_verify_failure
;
1485 uschar
*ko_prefix
, *cr
;
1486 uschar
*address
= vaddr
->address
;
1487 uschar
*save_sender
;
1488 uschar null_sender
[] = { 0 }; /* Ensure writeable memory */
1490 /* Clear, just in case */
1492 *failure_ptr
= NULL
;
1494 /* Set up a prefix and suffix for error message which allow us to use the same
1495 output statements both in EXPN mode (where an SMTP response is needed) and when
1496 debugging with an output file. */
1500 ko_prefix
= US
"553 ";
1503 else ko_prefix
= cr
= US
"";
1505 /* Add qualify domain if permitted; otherwise an unqualified address fails. */
1507 if (parse_find_at(address
) == NULL
)
1509 if ((options
& vopt_qualify
) == 0)
1512 respond_printf(f
, "%sA domain is required for \"%s\"%s\n",
1513 ko_prefix
, address
, cr
);
1514 *failure_ptr
= US
"qualify";
1517 address
= rewrite_address_qualify(address
, is_recipient
);
1522 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1523 debug_printf("%s %s\n", address_test_mode
? "Testing" : "Verifying", address
);
1526 /* Rewrite and report on it. Clear the domain and local part caches - these
1527 may have been set by domains and local part tests during an ACL. */
1529 if (global_rewrite_rules
!= NULL
)
1531 uschar
*old
= address
;
1532 address
= rewrite_address(address
, is_recipient
, FALSE
,
1533 global_rewrite_rules
, rewrite_existflags
);
1536 for (i
= 0; i
< (MAX_NAMED_LIST
* 2)/32; i
++) vaddr
->localpart_cache
[i
] = 0;
1537 for (i
= 0; i
< (MAX_NAMED_LIST
* 2)/32; i
++) vaddr
->domain_cache
[i
] = 0;
1538 if (f
!= NULL
&& !expn
) fprintf(f
, "Address rewritten as: %s\n", address
);
1542 /* If this is the real sender address, we must update sender_address at
1543 this point, because it may be referred to in the routers. */
1545 if ((options
& (vopt_fake_sender
|vopt_is_recipient
)) == 0)
1546 sender_address
= address
;
1548 /* If the address was rewritten to <> no verification can be done, and we have
1549 to return OK. This rewriting is permitted only for sender addresses; for other
1550 addresses, such rewriting fails. */
1552 if (address
[0] == 0) return OK
;
1554 /* Flip the legacy TLS-related variables over to the outbound set in case
1555 they're used in the context of a transport used by verification. Reset them
1556 at exit from this routine. */
1558 modify_variable(US
"tls_bits", &tls_out
.bits
);
1559 modify_variable(US
"tls_certificate_verified", &tls_out
.certificate_verified
);
1560 modify_variable(US
"tls_cipher", &tls_out
.cipher
);
1561 modify_variable(US
"tls_peerdn", &tls_out
.peerdn
);
1562 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1563 modify_variable(US
"tls_sni", &tls_out
.sni
);
1566 /* Save a copy of the sender address for re-instating if we change it to <>
1567 while verifying a sender address (a nice bit of self-reference there). */
1569 save_sender
= sender_address
;
1571 /* Update the address structure with the possibly qualified and rewritten
1572 address. Set it up as the starting address on the chain of new addresses. */
1574 vaddr
->address
= address
;
1577 /* We need a loop, because an address can generate new addresses. We must also
1578 cope with generated pipes and files at the top level. (See also the code and
1579 comment in deliver.c.) However, it is usually the case that the router for
1580 user's .forward files has its verify flag turned off.
1582 If an address generates more than one child, the loop is used only when
1583 full_info is set, and this can only be set locally. Remote enquiries just get
1584 information about the top level address, not anything that it generated. */
1586 while (addr_new
!= NULL
)
1589 address_item
*addr
= addr_new
;
1591 addr_new
= addr
->next
;
1596 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1597 debug_printf("Considering %s\n", addr
->address
);
1600 /* Handle generated pipe, file or reply addresses. We don't get these
1601 when handling EXPN, as it does only one level of expansion. */
1603 if (testflag(addr
, af_pfr
))
1610 if (addr
->address
[0] == '>')
1612 allow
= testflag(addr
, af_allow_reply
);
1613 fprintf(f
, "%s -> mail %s", addr
->parent
->address
, addr
->address
+ 1);
1617 allow
= (addr
->address
[0] == '|')?
1618 testflag(addr
, af_allow_pipe
) : testflag(addr
, af_allow_file
);
1619 fprintf(f
, "%s -> %s", addr
->parent
->address
, addr
->address
);
1622 if (addr
->basic_errno
== ERRNO_BADTRANSPORT
)
1623 fprintf(f
, "\n*** Error in setting up pipe, file, or autoreply:\n"
1624 "%s\n", addr
->message
);
1626 fprintf(f
, "\n transport = %s\n", addr
->transport
->name
);
1628 fprintf(f
, " *** forbidden ***\n");
1633 /* Just in case some router parameter refers to it. */
1635 return_path
= (addr
->p
.errors_address
!= NULL
)?
1636 addr
->p
.errors_address
: sender_address
;
1638 /* Split the address into domain and local part, handling the %-hack if
1639 necessary, and then route it. While routing a sender address, set
1640 $sender_address to <> because that is what it will be if we were trying to
1641 send a bounce to the sender. */
1643 if (routed
!= NULL
) *routed
= FALSE
;
1644 if ((rc
= deliver_split_address(addr
)) == OK
)
1646 if (!is_recipient
) sender_address
= null_sender
;
1647 rc
= route_address(addr
, &addr_local
, &addr_remote
, &addr_new
,
1648 &addr_succeed
, verify_type
);
1649 sender_address
= save_sender
; /* Put back the real sender */
1652 /* If routing an address succeeded, set the flag that remembers, for use when
1653 an ACL cached a sender verify (in case a callout fails). Then if routing set
1654 up a list of hosts or the transport has a host list, and the callout option
1655 is set, and we aren't in a host checking run, do the callout verification,
1656 and set another flag that notes that a callout happened. */
1660 if (routed
!= NULL
) *routed
= TRUE
;
1663 host_item
*host_list
= addr
->host_list
;
1665 /* Make up some data for use in the case where there is no remote
1668 transport_feedback tf
= {
1669 NULL
, /* interface (=> any) */
1670 US
"smtp", /* port */
1671 US
"smtp", /* protocol */
1673 US
"$smtp_active_hostname", /* helo_data */
1674 FALSE
, /* hosts_override */
1675 FALSE
, /* hosts_randomize */
1676 FALSE
, /* gethostbyname */
1677 TRUE
, /* qualify_single */
1678 FALSE
/* search_parents */
1681 /* If verification yielded a remote transport, we want to use that
1682 transport's options, so as to mimic what would happen if we were really
1683 sending a message to this address. */
1685 if (addr
->transport
!= NULL
&& !addr
->transport
->info
->local
)
1687 (void)(addr
->transport
->setup
)(addr
->transport
, addr
, &tf
, 0, 0, NULL
);
1689 /* If the transport has hosts and the router does not, or if the
1690 transport is configured to override the router's hosts, we must build a
1691 host list of the transport's hosts, and find the IP addresses */
1693 if (tf
.hosts
!= NULL
&& (host_list
== NULL
|| tf
.hosts_override
))
1696 uschar
*save_deliver_domain
= deliver_domain
;
1697 uschar
*save_deliver_localpart
= deliver_localpart
;
1699 host_list
= NULL
; /* Ignore the router's hosts */
1701 deliver_domain
= addr
->domain
;
1702 deliver_localpart
= addr
->local_part
;
1703 s
= expand_string(tf
.hosts
);
1704 deliver_domain
= save_deliver_domain
;
1705 deliver_localpart
= save_deliver_localpart
;
1709 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to expand list of hosts "
1710 "\"%s\" in %s transport for callout: %s", tf
.hosts
,
1711 addr
->transport
->name
, expand_string_message
);
1716 uschar
*canonical_name
;
1717 host_item
*host
, *nexthost
;
1718 host_build_hostlist(&host_list
, s
, tf
.hosts_randomize
);
1720 /* Just ignore failures to find a host address. If we don't manage
1721 to find any addresses, the callout will defer. Note that more than
1722 one address may be found for a single host, which will result in
1723 additional host items being inserted into the chain. Hence we must
1724 save the next host first. */
1726 flags
= HOST_FIND_BY_A
;
1727 if (tf
.qualify_single
) flags
|= HOST_FIND_QUALIFY_SINGLE
;
1728 if (tf
.search_parents
) flags
|= HOST_FIND_SEARCH_PARENTS
;
1730 for (host
= host_list
; host
!= NULL
; host
= nexthost
)
1732 nexthost
= host
->next
;
1733 if (tf
.gethostbyname
||
1734 string_is_ip_address(host
->name
, NULL
) != 0)
1735 (void)host_find_byname(host
, NULL
, flags
, &canonical_name
, TRUE
);
1737 (void)host_find_bydns(host
, NULL
, flags
, NULL
, NULL
, NULL
,
1738 &canonical_name
, NULL
);
1744 /* Can only do a callout if we have at least one host! If the callout
1745 fails, it will have set ${sender,recipient}_verify_failure. */
1747 if (host_list
!= NULL
)
1749 HDEBUG(D_verify
) debug_printf("Attempting full verification using callout\n");
1750 if (host_checking
&& !host_checking_callout
)
1753 debug_printf("... callout omitted by default when host testing\n"
1754 "(Use -bhc if you want the callouts to happen.)\n");
1759 deliver_set_expansions(addr
);
1761 rc
= do_callout(addr
, host_list
, &tf
, callout
, callout_overall
,
1762 callout_connect
, options
, se_mailfrom
, pm_mailfrom
);
1767 HDEBUG(D_verify
) debug_printf("Cannot do callout: neither router nor "
1768 "transport provided a host list\n");
1773 /* Otherwise, any failure is a routing failure */
1775 else *failure_ptr
= US
"route";
1777 /* A router may return REROUTED if it has set up a child address as a result
1778 of a change of domain name (typically from widening). In this case we always
1779 want to continue to verify the new child. */
1781 if (rc
== REROUTED
) continue;
1783 /* Handle hard failures */
1790 address_item
*p
= addr
->parent
;
1792 respond_printf(f
, "%s%s %s", ko_prefix
,
1793 full_info
? addr
->address
: address
,
1794 address_test_mode
? "is undeliverable" : "failed to verify");
1795 if (!expn
&& admin_user
)
1797 if (addr
->basic_errno
> 0)
1798 respond_printf(f
, ": %s", strerror(addr
->basic_errno
));
1799 if (addr
->message
!= NULL
)
1800 respond_printf(f
, ": %s", addr
->message
);
1803 /* Show parents iff doing full info */
1805 if (full_info
) while (p
!= NULL
)
1807 respond_printf(f
, "%s\n <-- %s", cr
, p
->address
);
1810 respond_printf(f
, "%s\n", cr
);
1812 cancel_cutthrough_connection("routing hard fail");
1816 yield
= copy_error(vaddr
, addr
, FAIL
);
1824 else if (rc
== DEFER
)
1829 address_item
*p
= addr
->parent
;
1830 respond_printf(f
, "%s%s cannot be resolved at this time", ko_prefix
,
1831 full_info
? addr
->address
: address
);
1832 if (!expn
&& admin_user
)
1834 if (addr
->basic_errno
> 0)
1835 respond_printf(f
, ": %s", strerror(addr
->basic_errno
));
1836 if (addr
->message
!= NULL
)
1837 respond_printf(f
, ": %s", addr
->message
);
1838 else if (addr
->basic_errno
<= 0)
1839 respond_printf(f
, ": unknown error");
1842 /* Show parents iff doing full info */
1844 if (full_info
) while (p
!= NULL
)
1846 respond_printf(f
, "%s\n <-- %s", cr
, p
->address
);
1849 respond_printf(f
, "%s\n", cr
);
1851 cancel_cutthrough_connection("routing soft fail");
1855 yield
= copy_error(vaddr
, addr
, DEFER
);
1858 else if (yield
== OK
) yield
= DEFER
;
1861 /* If we are handling EXPN, we do not want to continue to route beyond
1862 the top level (whose address is in "address"). */
1866 uschar
*ok_prefix
= US
"250-";
1867 if (addr_new
== NULL
)
1869 if (addr_local
== NULL
&& addr_remote
== NULL
)
1870 respond_printf(f
, "250 mail to <%s> is discarded\r\n", address
);
1872 respond_printf(f
, "250 <%s>\r\n", address
);
1874 else while (addr_new
!= NULL
)
1876 address_item
*addr2
= addr_new
;
1877 addr_new
= addr2
->next
;
1878 if (addr_new
== NULL
) ok_prefix
= US
"250 ";
1879 respond_printf(f
, "%s<%s>\r\n", ok_prefix
, addr2
->address
);
1885 /* Successful routing other than EXPN. */
1889 /* Handle successful routing when short info wanted. Otherwise continue for
1890 other (generated) addresses. Short info is the operational case. Full info
1891 can be requested only when debug_selector != 0 and a file is supplied.
1893 There is a conflict between the use of aliasing as an alternate email
1894 address, and as a sort of mailing list. If an alias turns the incoming
1895 address into just one address (e.g. J.Caesar->jc44) you may well want to
1896 carry on verifying the generated address to ensure it is valid when
1897 checking incoming mail. If aliasing generates multiple addresses, you
1898 probably don't want to do this. Exim therefore treats the generation of
1899 just a single new address as a special case, and continues on to verify the
1900 generated address. */
1902 if (!full_info
&& /* Stop if short info wanted AND */
1903 (((addr_new
== NULL
|| /* No new address OR */
1904 addr_new
->next
!= NULL
|| /* More than one new address OR */
1905 testflag(addr_new
, af_pfr
))) /* New address is pfr */
1907 (addr_new
!= NULL
&& /* At least one new address AND */
1908 success_on_redirect
))) /* success_on_redirect is set */
1910 if (f
!= NULL
) fprintf(f
, "%s %s\n", address
,
1911 address_test_mode
? "is deliverable" : "verified");
1913 /* If we have carried on to verify a child address, we want the value
1914 of $address_data to be that of the child */
1916 vaddr
->p
.address_data
= addr
->p
.address_data
;
1921 } /* Loop for generated addresses */
1923 /* Display the full results of the successful routing, including any generated
1924 addresses. Control gets here only when full_info is set, which requires f not
1925 to be NULL, and this occurs only when a top-level verify is called with the
1926 debugging switch on.
1928 If there are no local and no remote addresses, and there were no pipes, files,
1929 or autoreplies, and there were no errors or deferments, the message is to be
1930 discarded, usually because of the use of :blackhole: in an alias file. */
1932 if (allok
&& addr_local
== NULL
&& addr_remote
== NULL
)
1934 fprintf(f
, "mail to %s is discarded\n", address
);
1938 for (addr_list
= addr_local
, i
= 0; i
< 2; addr_list
= addr_remote
, i
++)
1940 while (addr_list
!= NULL
)
1942 address_item
*addr
= addr_list
;
1943 address_item
*p
= addr
->parent
;
1944 addr_list
= addr
->next
;
1946 fprintf(f
, "%s", CS addr
->address
);
1947 #ifdef EXPERIMENTAL_SRS
1948 if(addr
->p
.srs_sender
)
1949 fprintf(f
, " [srs = %s]", addr
->p
.srs_sender
);
1952 /* If the address is a duplicate, show something about it. */
1954 if (!testflag(addr
, af_pfr
))
1957 if ((tnode
= tree_search(tree_duplicates
, addr
->unique
)) != NULL
)
1958 fprintf(f
, " [duplicate, would not be delivered]");
1959 else tree_add_duplicate(addr
->unique
, addr
);
1962 /* Now show its parents */
1966 fprintf(f
, "\n <-- %s", p
->address
);
1971 /* Show router, and transport */
1973 fprintf(f
, "router = %s, ", addr
->router
->name
);
1974 fprintf(f
, "transport = %s\n", (addr
->transport
== NULL
)? US
"unset" :
1975 addr
->transport
->name
);
1977 /* Show any hosts that are set up by a router unless the transport
1978 is going to override them; fiddle a bit to get a nice format. */
1980 if (addr
->host_list
!= NULL
&& addr
->transport
!= NULL
&&
1981 !addr
->transport
->overrides_hosts
)
1986 for (h
= addr
->host_list
; h
!= NULL
; h
= h
->next
)
1988 int len
= Ustrlen(h
->name
);
1989 if (len
> maxlen
) maxlen
= len
;
1990 len
= (h
->address
!= NULL
)? Ustrlen(h
->address
) : 7;
1991 if (len
> maxaddlen
) maxaddlen
= len
;
1993 for (h
= addr
->host_list
; h
!= NULL
; h
= h
->next
)
1995 int len
= Ustrlen(h
->name
);
1996 fprintf(f
, " host %s ", h
->name
);
1997 while (len
++ < maxlen
) fprintf(f
, " ");
1998 if (h
->address
!= NULL
)
2000 fprintf(f
, "[%s] ", h
->address
);
2001 len
= Ustrlen(h
->address
);
2003 else if (!addr
->transport
->info
->local
) /* Omit [unknown] for local */
2005 fprintf(f
, "[unknown] ");
2009 while (len
++ < maxaddlen
) fprintf(f
," ");
2010 if (h
->mx
>= 0) fprintf(f
, "MX=%d", h
->mx
);
2011 if (h
->port
!= PORT_NONE
) fprintf(f
, " port=%d", h
->port
);
2012 if (h
->status
== hstatus_unusable
) fprintf(f
, " ** unusable **");
2019 /* Yield will be DEFER or FAIL if any one address has, only for full_info (which is
2020 the -bv or -bt case). */
2024 modify_variable(US
"tls_bits", &tls_in
.bits
);
2025 modify_variable(US
"tls_certificate_verified", &tls_in
.certificate_verified
);
2026 modify_variable(US
"tls_cipher", &tls_in
.cipher
);
2027 modify_variable(US
"tls_peerdn", &tls_in
.peerdn
);
2028 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
2029 modify_variable(US
"tls_sni", &tls_in
.sni
);
2038 /*************************************************
2039 * Check headers for syntax errors *
2040 *************************************************/
2042 /* This function checks those header lines that contain addresses, and verifies
2043 that all the addresses therein are syntactially correct.
2046 msgptr where to put an error message
2053 verify_check_headers(uschar
**msgptr
)
2059 for (h
= header_list
; h
!= NULL
&& yield
== OK
; h
= h
->next
)
2061 if (h
->type
!= htype_from
&&
2062 h
->type
!= htype_reply_to
&&
2063 h
->type
!= htype_sender
&&
2064 h
->type
!= htype_to
&&
2065 h
->type
!= htype_cc
&&
2066 h
->type
!= htype_bcc
)
2069 colon
= Ustrchr(h
->text
, ':');
2071 while (isspace(*s
)) s
++;
2073 /* Loop for multiple addresses in the header, enabling group syntax. Note
2074 that we have to reset this after the header has been scanned. */
2076 parse_allow_group
= TRUE
;
2080 uschar
*ss
= parse_find_address_end(s
, FALSE
);
2081 uschar
*recipient
, *errmess
;
2082 int terminator
= *ss
;
2083 int start
, end
, domain
;
2085 /* Temporarily terminate the string at this point, and extract the
2086 operative address within, allowing group syntax. */
2089 recipient
= parse_extract_address(s
,&errmess
,&start
,&end
,&domain
,FALSE
);
2092 /* Permit an unqualified address only if the message is local, or if the
2093 sending host is configured to be permitted to send them. */
2095 if (recipient
!= NULL
&& domain
== 0)
2097 if (h
->type
== htype_from
|| h
->type
== htype_sender
)
2099 if (!allow_unqualified_sender
) recipient
= NULL
;
2103 if (!allow_unqualified_recipient
) recipient
= NULL
;
2105 if (recipient
== NULL
) errmess
= US
"unqualified address not permitted";
2108 /* It's an error if no address could be extracted, except for the special
2109 case of an empty address. */
2111 if (recipient
== NULL
&& Ustrcmp(errmess
, "empty address") != 0)
2113 uschar
*verb
= US
"is";
2118 /* Arrange not to include any white space at the end in the
2119 error message or the header name. */
2121 while (t
> s
&& isspace(t
[-1])) t
--;
2122 while (tt
> h
->text
&& isspace(tt
[-1])) tt
--;
2124 /* Add the address that failed to the error message, since in a
2125 header with very many addresses it is sometimes hard to spot
2126 which one is at fault. However, limit the amount of address to
2127 quote - cases have been seen where, for example, a missing double
2128 quote in a humungous To: header creates an "address" that is longer
2129 than string_sprintf can handle. */
2138 *msgptr
= string_printing(
2139 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
2140 errmess
, tt
- h
->text
, h
->text
, verb
, len
, s
));
2143 break; /* Out of address loop */
2146 /* Advance to the next address */
2148 s
= ss
+ (terminator
? 1:0);
2149 while (isspace(*s
)) s
++;
2150 } /* Next address */
2152 parse_allow_group
= FALSE
;
2153 parse_found_group
= FALSE
;
2154 } /* Next header unless yield has been set FALSE */
2160 /*************************************************
2161 * Check header names for 8-bit characters *
2162 *************************************************/
2164 /* This function checks for invalid charcters in header names. See
2165 RFC 5322, 2.2. and RFC 6532, 3.
2168 msgptr where to put an error message
2175 verify_check_header_names_ascii(uschar
**msgptr
)
2180 for (h
= header_list
; h
!= NULL
; h
= h
->next
)
2182 colon
= Ustrchr(h
->text
, ':');
2183 for(s
= h
->text
; s
< colon
; s
++)
2185 if ((*s
< 33) || (*s
> 126))
2187 *msgptr
= string_sprintf("Invalid character in header \"%.*s\" found",
2188 colon
- h
->text
, h
->text
);
2196 /*************************************************
2197 * Check for blind recipients *
2198 *************************************************/
2200 /* This function checks that every (envelope) recipient is mentioned in either
2201 the To: or Cc: header lines, thus detecting blind carbon copies.
2203 There are two ways of scanning that could be used: either scan the header lines
2204 and tick off the recipients, or scan the recipients and check the header lines.
2205 The original proposed patch did the former, but I have chosen to do the latter,
2206 because (a) it requires no memory and (b) will use fewer resources when there
2207 are many addresses in To: and/or Cc: and only one or two envelope recipients.
2210 Returns: OK if there are no blind recipients
2211 FAIL if there is at least one blind recipient
2215 verify_check_notblind(void)
2218 for (i
= 0; i
< recipients_count
; i
++)
2222 uschar
*address
= recipients_list
[i
].address
;
2224 for (h
= header_list
; !found
&& h
!= NULL
; h
= h
->next
)
2228 if (h
->type
!= htype_to
&& h
->type
!= htype_cc
) continue;
2230 colon
= Ustrchr(h
->text
, ':');
2232 while (isspace(*s
)) s
++;
2234 /* Loop for multiple addresses in the header, enabling group syntax. Note
2235 that we have to reset this after the header has been scanned. */
2237 parse_allow_group
= TRUE
;
2241 uschar
*ss
= parse_find_address_end(s
, FALSE
);
2242 uschar
*recipient
,*errmess
;
2243 int terminator
= *ss
;
2244 int start
, end
, domain
;
2246 /* Temporarily terminate the string at this point, and extract the
2247 operative address within, allowing group syntax. */
2250 recipient
= parse_extract_address(s
,&errmess
,&start
,&end
,&domain
,FALSE
);
2253 /* If we found a valid recipient that has a domain, compare it with the
2254 envelope recipient. Local parts are compared case-sensitively, domains
2255 case-insensitively. By comparing from the start with length "domain", we
2256 include the "@" at the end, which ensures that we are comparing the whole
2257 local part of each address. */
2259 if (recipient
!= NULL
&& domain
!= 0)
2261 found
= Ustrncmp(recipient
, address
, domain
) == 0 &&
2262 strcmpic(recipient
+ domain
, address
+ domain
) == 0;
2266 /* Advance to the next address */
2268 s
= ss
+ (terminator
? 1:0);
2269 while (isspace(*s
)) s
++;
2270 } /* Next address */
2272 parse_allow_group
= FALSE
;
2273 parse_found_group
= FALSE
;
2274 } /* Next header (if found is false) */
2276 if (!found
) return FAIL
;
2277 } /* Next recipient */
2284 /*************************************************
2285 * Find if verified sender *
2286 *************************************************/
2288 /* Usually, just a single address is verified as the sender of the message.
2289 However, Exim can be made to verify other addresses as well (often related in
2290 some way), and this is useful in some environments. There may therefore be a
2291 chain of such addresses that have previously been tested. This function finds
2292 whether a given address is on the chain.
2294 Arguments: the address to be verified
2295 Returns: pointer to an address item, or NULL
2299 verify_checked_sender(uschar
*sender
)
2302 for (addr
= sender_verified_list
; addr
!= NULL
; addr
= addr
->next
)
2303 if (Ustrcmp(sender
, addr
->address
) == 0) break;
2311 /*************************************************
2312 * Get valid header address *
2313 *************************************************/
2315 /* Scan the originator headers of the message, looking for an address that
2316 verifies successfully. RFC 822 says:
2318 o The "Sender" field mailbox should be sent notices of
2319 any problems in transport or delivery of the original
2320 messages. If there is no "Sender" field, then the
2321 "From" field mailbox should be used.
2323 o If the "Reply-To" field exists, then the reply should
2324 go to the addresses indicated in that field and not to
2325 the address(es) indicated in the "From" field.
2327 So we check a Sender field if there is one, else a Reply_to field, else a From
2328 field. As some strange messages may have more than one of these fields,
2329 especially if they are resent- fields, check all of them if there is more than
2333 user_msgptr points to where to put a user error message
2334 log_msgptr points to where to put a log error message
2335 callout timeout for callout check (passed to verify_address())
2336 callout_overall overall callout timeout (ditto)
2337 callout_connect connect callout timeout (ditto)
2338 se_mailfrom mailfrom for verify; NULL => ""
2339 pm_mailfrom sender for pm callout check (passed to verify_address())
2340 options callout options (passed to verify_address())
2341 verrno where to put the address basic_errno
2343 If log_msgptr is set to something without setting user_msgptr, the caller
2344 normally uses log_msgptr for both things.
2346 Returns: result of the verification attempt: OK, FAIL, or DEFER;
2347 FAIL is given if no appropriate headers are found
2351 verify_check_header_address(uschar
**user_msgptr
, uschar
**log_msgptr
,
2352 int callout
, int callout_overall
, int callout_connect
, uschar
*se_mailfrom
,
2353 uschar
*pm_mailfrom
, int options
, int *verrno
)
2355 static int header_types
[] = { htype_sender
, htype_reply_to
, htype_from
};
2360 for (i
= 0; i
< 3 && !done
; i
++)
2363 for (h
= header_list
; h
!= NULL
&& !done
; h
= h
->next
)
2365 int terminator
, new_ok
;
2366 uschar
*s
, *ss
, *endname
;
2368 if (h
->type
!= header_types
[i
]) continue;
2369 s
= endname
= Ustrchr(h
->text
, ':') + 1;
2371 /* Scan the addresses in the header, enabling group syntax. Note that we
2372 have to reset this after the header has been scanned. */
2374 parse_allow_group
= TRUE
;
2378 address_item
*vaddr
;
2380 while (isspace(*s
) || *s
== ',') s
++;
2381 if (*s
== 0) break; /* End of header */
2383 ss
= parse_find_address_end(s
, FALSE
);
2385 /* The terminator is a comma or end of header, but there may be white
2386 space preceding it (including newline for the last address). Move back
2387 past any white space so we can check against any cached envelope sender
2388 address verifications. */
2390 while (isspace(ss
[-1])) ss
--;
2394 HDEBUG(D_verify
) debug_printf("verifying %.*s header address %s\n",
2395 (int)(endname
- h
->text
), h
->text
, s
);
2397 /* See if we have already verified this address as an envelope sender,
2398 and if so, use the previous answer. */
2400 vaddr
= verify_checked_sender(s
);
2402 if (vaddr
!= NULL
&& /* Previously checked */
2403 (callout
<= 0 || /* No callout needed; OR */
2404 vaddr
->special_action
> 256)) /* Callout was done */
2406 new_ok
= vaddr
->special_action
& 255;
2407 HDEBUG(D_verify
) debug_printf("previously checked as envelope sender\n");
2408 *ss
= terminator
; /* Restore shortened string */
2411 /* Otherwise we run the verification now. We must restore the shortened
2412 string before running the verification, so the headers are correct, in
2413 case there is any rewriting. */
2417 int start
, end
, domain
;
2418 uschar
*address
= parse_extract_address(s
, log_msgptr
, &start
, &end
,
2423 /* If we found an empty address, just carry on with the next one, but
2424 kill the message. */
2426 if (address
== NULL
&& Ustrcmp(*log_msgptr
, "empty address") == 0)
2433 /* If verification failed because of a syntax error, fail this
2434 function, and ensure that the failing address gets added to the error
2437 if (address
== NULL
)
2440 while (ss
> s
&& isspace(ss
[-1])) ss
--;
2441 *log_msgptr
= string_sprintf("syntax error in '%.*s' header when "
2442 "scanning for sender: %s in \"%.*s\"",
2443 endname
- h
->text
, h
->text
, *log_msgptr
, ss
- s
, s
);
2449 /* Else go ahead with the sender verification. But it isn't *the*
2450 sender of the message, so set vopt_fake_sender to stop sender_address
2451 being replaced after rewriting or qualification. */
2455 vaddr
= deliver_make_addr(address
, FALSE
);
2456 new_ok
= verify_address(vaddr
, NULL
, options
| vopt_fake_sender
,
2457 callout
, callout_overall
, callout_connect
, se_mailfrom
,
2462 /* We now have the result, either newly found, or cached. If we are
2463 giving out error details, set a specific user error. This means that the
2464 last of these will be returned to the user if all three fail. We do not
2465 set a log message - the generic one below will be used. */
2469 *verrno
= vaddr
->basic_errno
;
2470 if (smtp_return_error_details
)
2472 *user_msgptr
= string_sprintf("Rejected after DATA: "
2473 "could not verify \"%.*s\" header address\n%s: %s",
2474 endname
- h
->text
, h
->text
, vaddr
->address
, vaddr
->message
);
2478 /* Success or defer */
2487 if (new_ok
== DEFER
) yield
= DEFER
;
2489 /* Move on to any more addresses in the header */
2492 } /* Next address */
2494 parse_allow_group
= FALSE
;
2495 parse_found_group
= FALSE
;
2496 } /* Next header, unless done */
2497 } /* Next header type unless done */
2499 if (yield
== FAIL
&& *log_msgptr
== NULL
)
2500 *log_msgptr
= US
"there is no valid sender in any header line";
2502 if (yield
== DEFER
&& *log_msgptr
== NULL
)
2503 *log_msgptr
= US
"all attempts to verify a sender in a header line deferred";
2511 /*************************************************
2512 * Get RFC 1413 identification *
2513 *************************************************/
2515 /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
2516 the timeout is set to zero, then the query is not done. There may also be lists
2517 of hosts and nets which are exempt. To guard against malefactors sending
2518 non-printing characters which could, for example, disrupt a message's headers,
2519 make sure the string consists of printing characters only.
2522 port the port to connect to; usually this is IDENT_PORT (113), but when
2523 running in the test harness with -bh a different value is used.
2527 Side effect: any received ident value is put in sender_ident (NULL otherwise)
2531 verify_get_ident(int port
)
2533 int sock
, host_af
, qlen
;
2534 int received_sender_port
, received_interface_port
, n
;
2536 uschar buffer
[2048];
2538 /* Default is no ident. Check whether we want to do an ident check for this
2541 sender_ident
= NULL
;
2542 if (rfc1413_query_timeout
<= 0 || verify_check_host(&rfc1413_hosts
) != OK
)
2545 DEBUG(D_ident
) debug_printf("doing ident callback\n");
2547 /* Set up a connection to the ident port of the remote host. Bind the local end
2548 to the incoming interface address. If the sender host address is an IPv6
2549 address, the incoming interface address will also be IPv6. */
2551 host_af
= (Ustrchr(sender_host_address
, ':') == NULL
)? AF_INET
: AF_INET6
;
2552 sock
= ip_socket(SOCK_STREAM
, host_af
);
2553 if (sock
< 0) return;
2555 if (ip_bind(sock
, host_af
, interface_address
, 0) < 0)
2557 DEBUG(D_ident
) debug_printf("bind socket for ident failed: %s\n",
2562 if (ip_connect(sock
, host_af
, sender_host_address
, port
, rfc1413_query_timeout
)
2565 if (errno
== ETIMEDOUT
&& (log_extra_selector
& LX_ident_timeout
) != 0)
2567 log_write(0, LOG_MAIN
, "ident connection to %s timed out",
2568 sender_host_address
);
2572 DEBUG(D_ident
) debug_printf("ident connection to %s failed: %s\n",
2573 sender_host_address
, strerror(errno
));
2578 /* Construct and send the query. */
2580 sprintf(CS buffer
, "%d , %d\r\n", sender_host_port
, interface_port
);
2581 qlen
= Ustrlen(buffer
);
2582 if (send(sock
, buffer
, qlen
, 0) < 0)
2584 DEBUG(D_ident
) debug_printf("ident send failed: %s\n", strerror(errno
));
2588 /* Read a response line. We put it into the rest of the buffer, using several
2589 recv() calls if necessary. */
2597 int size
= sizeof(buffer
) - (p
- buffer
);
2599 if (size
<= 0) goto END_OFF
; /* Buffer filled without seeing \n. */
2600 count
= ip_recv(sock
, p
, size
, rfc1413_query_timeout
);
2601 if (count
<= 0) goto END_OFF
; /* Read error or EOF */
2603 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
2604 generous, and accept a plain \n terminator as well. The only illegal
2607 for (pp
= p
; pp
< p
+ count
; pp
++)
2609 if (*pp
== 0) goto END_OFF
; /* Zero octet not allowed */
2612 if (pp
[-1] == '\r') pp
--;
2614 goto GOT_DATA
; /* Break out of both loops */
2618 /* Reached the end of the data without finding \n. Let the loop continue to
2619 read some more, if there is room. */
2626 /* We have received a line of data. Check it carefully. It must start with the
2627 same two port numbers that we sent, followed by data as defined by the RFC. For
2630 12345 , 25 : USERID : UNIX :root
2632 However, the amount of white space may be different to what we sent. In the
2633 "osname" field there may be several sub-fields, comma separated. The data we
2634 actually want to save follows the third colon. Some systems put leading spaces
2635 in it - we discard those. */
2637 if (sscanf(CS buffer
+ qlen
, "%d , %d%n", &received_sender_port
,
2638 &received_interface_port
, &n
) != 2 ||
2639 received_sender_port
!= sender_host_port
||
2640 received_interface_port
!= interface_port
)
2643 p
= buffer
+ qlen
+ n
;
2644 while(isspace(*p
)) p
++;
2645 if (*p
++ != ':') goto END_OFF
;
2646 while(isspace(*p
)) p
++;
2647 if (Ustrncmp(p
, "USERID", 6) != 0) goto END_OFF
;
2649 while(isspace(*p
)) p
++;
2650 if (*p
++ != ':') goto END_OFF
;
2651 while (*p
!= 0 && *p
!= ':') p
++;
2652 if (*p
++ == 0) goto END_OFF
;
2653 while(isspace(*p
)) p
++;
2654 if (*p
== 0) goto END_OFF
;
2656 /* The rest of the line is the data we want. We turn it into printing
2657 characters when we save it, so that it cannot mess up the format of any logging
2658 or Received: lines into which it gets inserted. We keep a maximum of 127
2661 sender_ident
= string_printing(string_copyn(p
, 127));
2662 DEBUG(D_ident
) debug_printf("sender_ident = %s\n", sender_ident
);
2672 /*************************************************
2673 * Match host to a single host-list item *
2674 *************************************************/
2676 /* This function compares a host (name or address) against a single item
2677 from a host list. The host name gets looked up if it is needed and is not
2678 already known. The function is called from verify_check_this_host() via
2679 match_check_list(), which is why most of its arguments are in a single block.
2682 arg the argument block (see below)
2683 ss the host-list item
2684 valueptr where to pass back looked up data, or NULL
2685 error for error message when returning ERROR
2688 host_name (a) the host name, or
2689 (b) NULL, implying use sender_host_name and
2690 sender_host_aliases, looking them up if required, or
2691 (c) the empty string, meaning that only IP address matches
2693 host_address the host address
2694 host_ipv4 the IPv4 address taken from an IPv6 one
2698 DEFER lookup deferred
2699 ERROR (a) failed to find the host name or IP address, or
2700 (b) unknown lookup type specified, or
2701 (c) host name encountered when only IP addresses are
2706 check_host(void *arg
, uschar
*ss
, uschar
**valueptr
, uschar
**error
)
2708 check_host_block
*cb
= (check_host_block
*)arg
;
2711 BOOL iplookup
= FALSE
;
2712 BOOL isquery
= FALSE
;
2713 BOOL isiponly
= cb
->host_name
!= NULL
&& cb
->host_name
[0] == 0;
2718 /* Optimize for the special case when the pattern is "*". */
2720 if (*ss
== '*' && ss
[1] == 0) return OK
;
2722 /* If the pattern is empty, it matches only in the case when there is no host -
2723 this can occur in ACL checking for SMTP input using the -bs option. In this
2724 situation, the host address is the empty string. */
2726 if (cb
->host_address
[0] == 0) return (*ss
== 0)? OK
: FAIL
;
2727 if (*ss
== 0) return FAIL
;
2729 /* If the pattern is precisely "@" then match against the primary host name,
2730 provided that host name matching is permitted; if it's "@[]" match against the
2731 local host's IP addresses. */
2737 if (isiponly
) return ERROR
;
2738 ss
= primary_hostname
;
2740 else if (Ustrcmp(ss
, "@[]") == 0)
2742 ip_address_item
*ip
;
2743 for (ip
= host_find_interfaces(); ip
!= NULL
; ip
= ip
->next
)
2744 if (Ustrcmp(ip
->address
, cb
->host_address
) == 0) return OK
;
2749 /* If the pattern is an IP address, optionally followed by a bitmask count, do
2750 a (possibly masked) comparision with the current IP address. */
2752 if (string_is_ip_address(ss
, &maskoffset
) != 0)
2753 return (host_is_in_net(cb
->host_address
, ss
, maskoffset
)? OK
: FAIL
);
2755 /* The pattern is not an IP address. A common error that people make is to omit
2756 one component of an IPv4 address, either by accident, or believing that, for
2757 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,
2758 which it isn't. (Those applications that do accept 1.2.3 as an IP address
2759 interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
2760 ancient specification.) To aid in debugging these cases, we give a specific
2761 error if the pattern contains only digits and dots or contains a slash preceded
2762 only by digits and dots (a slash at the start indicates a file name and of
2763 course slashes may be present in lookups, but not preceded only by digits and
2766 for (t
= ss
; isdigit(*t
) || *t
== '.'; t
++);
2767 if (*t
== 0 || (*t
== '/' && t
!= ss
))
2769 *error
= US
"malformed IPv4 address or address mask";
2773 /* See if there is a semicolon in the pattern */
2775 semicolon
= Ustrchr(ss
, ';');
2777 /* If we are doing an IP address only match, then all lookups must be IP
2778 address lookups, even if there is no "net-". */
2782 iplookup
= semicolon
!= NULL
;
2785 /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
2786 a lookup on a masked IP network, in textual form. We obey this code even if we
2787 have already set iplookup, so as to skip over the "net-" prefix and to set the
2788 mask length. The net- stuff really only applies to single-key lookups where the
2789 key is implicit. For query-style lookups the key is specified in the query.
2790 From release 4.30, the use of net- for query style is no longer needed, but we
2791 retain it for backward compatibility. */
2793 if (Ustrncmp(ss
, "net", 3) == 0 && semicolon
!= NULL
)
2796 for (t
= ss
+ 3; isdigit(*t
); t
++) mlen
= mlen
* 10 + *t
- '0';
2797 if (mlen
== 0 && t
== ss
+3) mlen
= -1; /* No mask supplied */
2798 iplookup
= (*t
++ == '-');
2802 /* Do the IP address lookup if that is indeed what we have */
2810 uschar
*filename
, *key
, *result
;
2813 /* Find the search type */
2815 search_type
= search_findtype(t
, semicolon
- t
);
2817 if (search_type
< 0) log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "%s",
2818 search_error_message
);
2820 /* Adjust parameters for the type of lookup. For a query-style lookup, there
2821 is no file name, and the "key" is just the query. For query-style with a file
2822 name, we have to fish the file off the start of the query. For a single-key
2823 lookup, the key is the current IP address, masked appropriately, and
2824 reconverted to text form, with the mask appended. For IPv6 addresses, specify
2825 dot separators instead of colons, except when the lookup type is "iplsearch".
2828 if (mac_islookup(search_type
, lookup_absfilequery
))
2830 filename
= semicolon
+ 1;
2832 while (*key
!= 0 && !isspace(*key
)) key
++;
2833 filename
= string_copyn(filename
, key
- filename
);
2834 while (isspace(*key
)) key
++;
2836 else if (mac_islookup(search_type
, lookup_querystyle
))
2839 key
= semicolon
+ 1;
2841 else /* Single-key style */
2843 int sep
= (Ustrcmp(lookup_list
[search_type
]->name
, "iplsearch") == 0)?
2845 insize
= host_aton(cb
->host_address
, incoming
);
2846 host_mask(insize
, incoming
, mlen
);
2847 (void)host_nmtoa(insize
, incoming
, mlen
, buffer
, sep
);
2849 filename
= semicolon
+ 1;
2852 /* Now do the actual lookup; note that there is no search_close() because
2853 of the caching arrangements. */
2855 handle
= search_open(filename
, search_type
, 0, NULL
, NULL
);
2856 if (handle
== NULL
) log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "%s",
2857 search_error_message
);
2858 result
= search_find(handle
, filename
, key
, -1, NULL
, 0, 0, NULL
);
2859 if (valueptr
!= NULL
) *valueptr
= result
;
2860 return (result
!= NULL
)? OK
: search_find_defer
? DEFER
: FAIL
;
2863 /* The pattern is not an IP address or network reference of any kind. That is,
2864 it is a host name pattern. If this is an IP only match, there's an error in the
2869 *error
= US
"cannot match host name in match_ip list";
2873 /* Check the characters of the pattern to see if they comprise only letters,
2874 digits, full stops, and hyphens (the constituents of domain names). Allow
2875 underscores, as they are all too commonly found. Sigh. Also, if
2876 allow_utf8_domains is set, allow top-bit characters. */
2878 for (t
= ss
; *t
!= 0; t
++)
2879 if (!isalnum(*t
) && *t
!= '.' && *t
!= '-' && *t
!= '_' &&
2880 (!allow_utf8_domains
|| *t
< 128)) break;
2882 /* If the pattern is a complete domain name, with no fancy characters, look up
2883 its IP address and match against that. Note that a multi-homed host will add
2884 items to the chain. */
2895 rc
= host_find_byname(&h
, NULL
, HOST_FIND_QUALIFY_SINGLE
, NULL
, FALSE
);
2896 if (rc
== HOST_FOUND
|| rc
== HOST_FOUND_LOCAL
)
2899 for (hh
= &h
; hh
!= NULL
; hh
= hh
->next
)
2901 if (host_is_in_net(hh
->address
, cb
->host_address
, 0)) return OK
;
2905 if (rc
== HOST_FIND_AGAIN
) return DEFER
;
2906 *error
= string_sprintf("failed to find IP address for %s", ss
);
2910 /* Almost all subsequent comparisons require the host name, and can be done
2911 using the general string matching function. When this function is called for
2912 outgoing hosts, the name is always given explicitly. If it is NULL, it means we
2913 must use sender_host_name and its aliases, looking them up if necessary. */
2915 if (cb
->host_name
!= NULL
) /* Explicit host name given */
2916 return match_check_string(cb
->host_name
, ss
, -1, TRUE
, TRUE
, TRUE
,
2919 /* Host name not given; in principle we need the sender host name and its
2920 aliases. However, for query-style lookups, we do not need the name if the
2921 query does not contain $sender_host_name. From release 4.23, a reference to
2922 $sender_host_name causes it to be looked up, so we don't need to do the lookup
2925 if ((semicolon
= Ustrchr(ss
, ';')) != NULL
)
2928 int partial
, affixlen
, starflags
, id
;
2931 id
= search_findtype_partial(ss
, &partial
, &affix
, &affixlen
, &starflags
);
2934 if (id
< 0) /* Unknown lookup type */
2936 log_write(0, LOG_MAIN
|LOG_PANIC
, "%s in host list item \"%s\"",
2937 search_error_message
, ss
);
2940 isquery
= mac_islookup(id
, lookup_querystyle
|lookup_absfilequery
);
2945 switch(match_check_string(US
"", ss
, -1, TRUE
, TRUE
, TRUE
, valueptr
))
2948 case DEFER
: return DEFER
;
2949 default: return FAIL
;
2953 /* Not a query-style lookup; must ensure the host name is present, and then we
2954 do a check on the name and all its aliases. */
2956 if (sender_host_name
== NULL
)
2958 HDEBUG(D_host_lookup
)
2959 debug_printf("sender host name required, to match against %s\n", ss
);
2960 if (host_lookup_failed
|| host_name_lookup() != OK
)
2962 *error
= string_sprintf("failed to find host name for %s",
2963 sender_host_address
);;
2966 host_build_sender_fullhost();
2969 /* Match on the sender host name, using the general matching function */
2971 switch(match_check_string(sender_host_name
, ss
, -1, TRUE
, TRUE
, TRUE
,
2975 case DEFER
: return DEFER
;
2978 /* If there are aliases, try matching on them. */
2980 aliases
= sender_host_aliases
;
2981 while (*aliases
!= NULL
)
2983 switch(match_check_string(*aliases
++, ss
, -1, TRUE
, TRUE
, TRUE
, valueptr
))
2986 case DEFER
: return DEFER
;
2995 /*************************************************
2996 * Check a specific host matches a host list *
2997 *************************************************/
2999 /* This function is passed a host list containing items in a number of
3000 different formats and the identity of a host. Its job is to determine whether
3001 the given host is in the set of hosts defined by the list. The host name is
3002 passed as a pointer so that it can be looked up if needed and not already
3003 known. This is commonly the case when called from verify_check_host() to check
3004 an incoming connection. When called from elsewhere the host name should usually
3007 This function is now just a front end to match_check_list(), which runs common
3008 code for scanning a list. We pass it the check_host() function to perform a
3012 listptr pointer to the host list
3013 cache_bits pointer to cache for named lists, or NULL
3014 host_name the host name or NULL, implying use sender_host_name and
3015 sender_host_aliases, looking them up if required
3016 host_address the IP address
3017 valueptr if not NULL, data from a lookup is passed back here
3019 Returns: OK if the host is in the defined set
3020 FAIL if the host is not in the defined set,
3021 DEFER if a data lookup deferred (not a host lookup)
3023 If the host name was needed in order to make a comparison, and could not be
3024 determined from the IP address, the result is FAIL unless the item
3025 "+allow_unknown" was met earlier in the list, in which case OK is returned. */
3028 verify_check_this_host(uschar
**listptr
, unsigned int *cache_bits
,
3029 uschar
*host_name
, uschar
*host_address
, uschar
**valueptr
)
3032 unsigned int *local_cache_bits
= cache_bits
;
3033 uschar
*save_host_address
= deliver_host_address
;
3034 check_host_block cb
;
3035 cb
.host_name
= host_name
;
3036 cb
.host_address
= host_address
;
3038 if (valueptr
!= NULL
) *valueptr
= NULL
;
3040 /* If the host address starts off ::ffff: it is an IPv6 address in
3041 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
3044 cb
.host_ipv4
= (Ustrncmp(host_address
, "::ffff:", 7) == 0)?
3045 host_address
+ 7 : host_address
;
3047 /* During the running of the check, put the IP address into $host_address. In
3048 the case of calls from the smtp transport, it will already be there. However,
3049 in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
3050 the safe side, any existing setting is preserved, though as I write this
3051 (November 2004) I can't see any cases where it is actually needed. */
3053 deliver_host_address
= host_address
;
3054 rc
= match_check_list(
3055 listptr
, /* the list */
3056 0, /* separator character */
3057 &hostlist_anchor
, /* anchor pointer */
3058 &local_cache_bits
, /* cache pointer */
3059 check_host
, /* function for testing */
3060 &cb
, /* argument for function */
3061 MCL_HOST
, /* type of check */
3062 (host_address
== sender_host_address
)?
3063 US
"host" : host_address
, /* text for debugging */
3064 valueptr
); /* where to pass back data */
3065 deliver_host_address
= save_host_address
;
3072 /*************************************************
3073 * Check the remote host matches a list *
3074 *************************************************/
3076 /* This is a front end to verify_check_this_host(), created because checking
3077 the remote host is a common occurrence. With luck, a good compiler will spot
3078 the tail recursion and optimize it. If there's no host address, this is
3079 command-line SMTP input - check against an empty string for the address.
3082 listptr pointer to the host list
3084 Returns: the yield of verify_check_this_host(),
3085 i.e. OK, FAIL, or DEFER
3089 verify_check_host(uschar
**listptr
)
3091 return verify_check_this_host(listptr
, sender_host_cache
, NULL
,
3092 (sender_host_address
== NULL
)? US
"" : sender_host_address
, NULL
);
3099 /*************************************************
3100 * Invert an IP address *
3101 *************************************************/
3103 /* Originally just used for DNS xBL lists, now also used for the
3104 reverse_ip expansion operator.
3107 buffer where to put the answer
3108 address the address to invert
3112 invert_address(uschar
*buffer
, uschar
*address
)
3115 uschar
*bptr
= buffer
;
3117 /* If this is an IPv4 address mapped into IPv6 format, adjust the pointer
3118 to the IPv4 part only. */
3120 if (Ustrncmp(address
, "::ffff:", 7) == 0) address
+= 7;
3122 /* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is
3125 if (host_aton(address
, bin
) == 1)
3129 for (i
= 0; i
< 4; i
++)
3131 sprintf(CS bptr
, "%d.", x
& 255);
3132 while (*bptr
) bptr
++;
3137 /* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses
3138 in any DNS black lists, and the format in which they will be looked up is
3139 unknown. This is just a guess. */
3145 for (j
= 3; j
>= 0; j
--)
3148 for (i
= 0; i
< 8; i
++)
3150 sprintf(CS bptr
, "%x.", x
& 15);
3151 while (*bptr
) bptr
++;
3158 /* Remove trailing period -- this is needed so that both arbitrary
3159 dnsbl keydomains and inverted addresses may be combined with the
3160 same format string, "%s.%s" */
3167 /*************************************************
3168 * Perform a single dnsbl lookup *
3169 *************************************************/
3171 /* This function is called from verify_check_dnsbl() below. It is also called
3172 recursively from within itself when domain and domain_txt are different
3173 pointers, in order to get the TXT record from the alternate domain.
3176 domain the outer dnsbl domain
3177 domain_txt alternate domain to lookup TXT record on success; when the
3178 same domain is to be used, domain_txt == domain (that is,
3179 the pointers must be identical, not just the text)
3180 keydomain the current keydomain (for debug message)
3181 prepend subdomain to lookup (like keydomain, but
3182 reversed if IP address)
3183 iplist the list of matching IP addresses, or NULL for "any"
3184 bitmask true if bitmask matching is wanted
3185 match_type condition for 'succeed' result
3186 0 => Any RR in iplist (=)
3187 1 => No RR in iplist (!=)
3188 2 => All RRs in iplist (==)
3189 3 => Some RRs not in iplist (!==)
3190 the two bits are defined as MT_NOT and MT_ALL
3191 defer_return what to return for a defer
3193 Returns: OK if lookup succeeded
3198 one_check_dnsbl(uschar
*domain
, uschar
*domain_txt
, uschar
*keydomain
,
3199 uschar
*prepend
, uschar
*iplist
, BOOL bitmask
, int match_type
,
3205 dnsbl_cache_block
*cb
;
3206 int old_pool
= store_pool
;
3207 uschar query
[256]; /* DNS domain max length */
3209 /* Construct the specific query domainname */
3211 if (!string_format(query
, sizeof(query
), "%s.%s", prepend
, domain
))
3213 log_write(0, LOG_MAIN
|LOG_PANIC
, "dnslist query is too long "
3214 "(ignored): %s...", query
);
3218 /* Look for this query in the cache. */
3220 t
= tree_search(dnsbl_cache
, query
);
3222 /* If not cached from a previous lookup, we must do a DNS lookup, and
3223 cache the result in permanent memory. */
3227 store_pool
= POOL_PERM
;
3229 /* Set up a tree entry to cache the lookup */
3231 t
= store_get(sizeof(tree_node
) + Ustrlen(query
));
3232 Ustrcpy(t
->name
, query
);
3233 t
->data
.ptr
= cb
= store_get(sizeof(dnsbl_cache_block
));
3234 (void)tree_insertnode(&dnsbl_cache
, t
);
3236 /* Do the DNS loopup . */
3238 HDEBUG(D_dnsbl
) debug_printf("new DNS lookup for %s\n", query
);
3239 cb
->rc
= dns_basic_lookup(&dnsa
, query
, T_A
);
3240 cb
->text_set
= FALSE
;
3244 /* If the lookup succeeded, cache the RHS address. The code allows for
3245 more than one address - this was for complete generality and the possible
3246 use of A6 records. However, A6 records have been reduced to experimental
3247 status (August 2001) and may die out. So they may never get used at all,
3248 let alone in dnsbl records. However, leave the code here, just in case.
3250 Quite apart from one A6 RR generating multiple addresses, there are DNS
3251 lists that return more than one A record, so we must handle multiple
3252 addresses generated in that way as well. */
3254 if (cb
->rc
== DNS_SUCCEED
)
3257 dns_address
**addrp
= &(cb
->rhs
);
3258 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
3260 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
3262 if (rr
->type
== T_A
)
3264 dns_address
*da
= dns_address_from_rr(&dnsa
, rr
);
3268 while (da
->next
!= NULL
) da
= da
->next
;
3269 addrp
= &(da
->next
);
3274 /* If we didn't find any A records, change the return code. This can
3275 happen when there is a CNAME record but there are no A records for what
3278 if (cb
->rhs
== NULL
) cb
->rc
= DNS_NODATA
;
3281 store_pool
= old_pool
;
3284 /* Previous lookup was cached */
3288 HDEBUG(D_dnsbl
) debug_printf("using result of previous DNS lookup\n");
3292 /* We now have the result of the DNS lookup, either newly done, or cached
3293 from a previous call. If the lookup succeeded, check against the address
3294 list if there is one. This may be a positive equality list (introduced by
3295 "="), a negative equality list (introduced by "!="), a positive bitmask
3296 list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/
3298 if (cb
->rc
== DNS_SUCCEED
)
3300 dns_address
*da
= NULL
;
3301 uschar
*addlist
= cb
->rhs
->address
;
3303 /* For A and AAAA records, there may be multiple addresses from multiple
3304 records. For A6 records (currently not expected to be used) there may be
3305 multiple addresses from a single record. */
3307 for (da
= cb
->rhs
->next
; da
!= NULL
; da
= da
->next
)
3308 addlist
= string_sprintf("%s, %s", addlist
, da
->address
);
3310 HDEBUG(D_dnsbl
) debug_printf("DNS lookup for %s succeeded (yielding %s)\n",
3313 /* Address list check; this can be either for equality, or via a bitmask.
3314 In the latter case, all the bits must match. */
3318 for (da
= cb
->rhs
; da
!= NULL
; da
= da
->next
)
3322 uschar
*ptr
= iplist
;
3325 /* Handle exact matching */
3329 while ((res
= string_nextinlist(&ptr
, &ipsep
, ip
, sizeof(ip
))) != NULL
)
3331 if (Ustrcmp(CS da
->address
, ip
) == 0) break;
3335 /* Handle bitmask matching */
3342 /* At present, all known DNS blocking lists use A records, with
3343 IPv4 addresses on the RHS encoding the information they return. I
3344 wonder if this will linger on as the last vestige of IPv4 when IPv6
3345 is ubiquitous? Anyway, for now we use paranoia code to completely
3346 ignore IPv6 addresses. The default mask is 0, which always matches.
3347 We change this only for IPv4 addresses in the list. */
3349 if (host_aton(da
->address
, address
) == 1) mask
= address
[0];
3351 /* Scan the returned addresses, skipping any that are IPv6 */
3353 while ((res
= string_nextinlist(&ptr
, &ipsep
, ip
, sizeof(ip
))) != NULL
)
3355 if (host_aton(ip
, address
) != 1) continue;
3356 if ((address
[0] & mask
) == address
[0]) break;
3362 (a) An IP address in an any ('=') list matched, or
3363 (b) No IP address in an all ('==') list matched
3365 then we're done searching. */
3367 if (((match_type
& MT_ALL
) != 0) == (res
== NULL
)) break;
3370 /* If da == NULL, either
3372 (a) No IP address in an any ('=') list matched, or
3373 (b) An IP address in an all ('==') list didn't match
3375 so behave as if the DNSBL lookup had not succeeded, i.e. the host is not on
3378 if ((match_type
== MT_NOT
|| match_type
== MT_ALL
) != (da
== NULL
))
3386 res
= US
"was no match";
3389 res
= US
"was an exclude match";
3392 res
= US
"was an IP address that did not match";
3395 res
= US
"were no IP addresses that did not match";
3398 debug_printf("=> but we are not accepting this block class because\n");
3399 debug_printf("=> there %s for %s%c%s\n",
3401 ((match_type
& MT_ALL
) == 0)? "" : "=",
3402 bitmask
? '&' : '=', iplist
);
3408 /* Either there was no IP list, or the record matched, implying that the
3409 domain is on the list. We now want to find a corresponding TXT record. If an
3410 alternate domain is specified for the TXT record, call this function
3411 recursively to look that up; this has the side effect of re-checking that
3412 there is indeed an A record at the alternate domain. */
3414 if (domain_txt
!= domain
)
3415 return one_check_dnsbl(domain_txt
, domain_txt
, keydomain
, prepend
, NULL
,
3416 FALSE
, match_type
, defer_return
);
3418 /* If there is no alternate domain, look up a TXT record in the main domain
3419 if it has not previously been cached. */
3423 cb
->text_set
= TRUE
;
3424 if (dns_basic_lookup(&dnsa
, query
, T_TXT
) == DNS_SUCCEED
)
3427 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
3429 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
3430 if (rr
->type
== T_TXT
) break;
3433 int len
= (rr
->data
)[0];
3434 if (len
> 511) len
= 127;
3435 store_pool
= POOL_PERM
;
3436 cb
->text
= string_sprintf("%.*s", len
, (const uschar
*)(rr
->data
+1));
3437 store_pool
= old_pool
;
3442 dnslist_value
= addlist
;
3443 dnslist_text
= cb
->text
;
3447 /* There was a problem with the DNS lookup */
3449 if (cb
->rc
!= DNS_NOMATCH
&& cb
->rc
!= DNS_NODATA
)
3451 log_write(L_dnslist_defer
, LOG_MAIN
,
3452 "DNS list lookup defer (probably timeout) for %s: %s", query
,
3453 (defer_return
== OK
)? US
"assumed in list" :
3454 (defer_return
== FAIL
)? US
"assumed not in list" :
3455 US
"returned DEFER");
3456 return defer_return
;
3459 /* No entry was found in the DNS; continue for next domain */
3463 debug_printf("DNS lookup for %s failed\n", query
);
3464 debug_printf("=> that means %s is not listed at %s\n",
3474 /*************************************************
3475 * Check host against DNS black lists *
3476 *************************************************/
3478 /* This function runs checks against a list of DNS black lists, until one
3479 matches. Each item on the list can be of the form
3481 domain=ip-address/key
3483 The domain is the right-most domain that is used for the query, for example,
3484 blackholes.mail-abuse.org. If the IP address is present, there is a match only
3485 if the DNS lookup returns a matching IP address. Several addresses may be
3486 given, comma-separated, for example: x.y.z=127.0.0.1,127.0.0.2.
3488 If no key is given, what is looked up in the domain is the inverted IP address
3489 of the current client host. If a key is given, it is used to construct the
3490 domain for the lookup. For example:
3492 dsn.rfc-ignorant.org/$sender_address_domain
3494 After finding a match in the DNS, the domain is placed in $dnslist_domain, and
3495 then we check for a TXT record for an error message, and if found, save its
3496 value in $dnslist_text. We also cache everything in a tree, to optimize
3499 The TXT record is normally looked up in the same domain as the A record, but
3500 when many lists are combined in a single DNS domain, this will not be a very
3501 specific message. It is possible to specify a different domain for looking up
3502 TXT records; this is given before the main domain, comma-separated. For
3505 dnslists = http.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.2 : \
3506 socks.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.3
3508 The caching ensures that only one lookup in dnsbl.sorbs.net is done.
3510 Note: an address for testing RBL is 192.203.178.39
3511 Note: an address for testing DUL is 192.203.178.4
3512 Note: a domain for testing RFCI is example.tld.dsn.rfc-ignorant.org
3515 listptr the domain/address/data list
3517 Returns: OK successful lookup (i.e. the address is on the list), or
3518 lookup deferred after +include_unknown
3519 FAIL name not found, or no data found for the given type, or
3520 lookup deferred after +exclude_unknown (default)
3521 DEFER lookup failure, if +defer_unknown was set
3525 verify_check_dnsbl(uschar
**listptr
)
3528 int defer_return
= FAIL
;
3529 uschar
*list
= *listptr
;
3532 uschar buffer
[1024];
3533 uschar revadd
[128]; /* Long enough for IPv6 address */
3535 /* Indicate that the inverted IP address is not yet set up */
3539 /* In case this is the first time the DNS resolver is being used. */
3541 dns_init(FALSE
, FALSE
);
3543 /* Loop through all the domains supplied, until something matches */
3545 while ((domain
= string_nextinlist(&list
, &sep
, buffer
, sizeof(buffer
))) != NULL
)
3548 BOOL bitmask
= FALSE
;
3555 HDEBUG(D_dnsbl
) debug_printf("DNS list check: %s\n", domain
);
3557 /* Deal with special values that change the behaviour on defer */
3559 if (domain
[0] == '+')
3561 if (strcmpic(domain
, US
"+include_unknown") == 0) defer_return
= OK
;
3562 else if (strcmpic(domain
, US
"+exclude_unknown") == 0) defer_return
= FAIL
;
3563 else if (strcmpic(domain
, US
"+defer_unknown") == 0) defer_return
= DEFER
;
3565 log_write(0, LOG_MAIN
|LOG_PANIC
, "unknown item in dnslist (ignored): %s",
3570 /* See if there's explicit data to be looked up */
3572 key
= Ustrchr(domain
, '/');
3573 if (key
!= NULL
) *key
++ = 0;
3575 /* See if there's a list of addresses supplied after the domain name. This is
3576 introduced by an = or a & character; if preceded by = we require all matches
3577 and if preceded by ! we invert the result. */
3579 iplist
= Ustrchr(domain
, '=');
3583 iplist
= Ustrchr(domain
, '&');
3586 if (iplist
!= NULL
) /* Found either = or & */
3588 if (iplist
> domain
&& iplist
[-1] == '!') /* Handle preceding ! */
3590 match_type
|= MT_NOT
;
3594 *iplist
++ = 0; /* Terminate domain, move on */
3596 /* If we found = (bitmask == FALSE), check for == or =& */
3598 if (!bitmask
&& (*iplist
== '=' || *iplist
== '&'))
3600 bitmask
= *iplist
++ == '&';
3601 match_type
|= MT_ALL
;
3605 /* If there is a comma in the domain, it indicates that a second domain for
3606 looking up TXT records is provided, before the main domain. Otherwise we must
3607 set domain_txt == domain. */
3609 domain_txt
= domain
;
3610 comma
= Ustrchr(domain
, ',');
3617 /* Check that what we have left is a sensible domain name. There is no reason
3618 why these domains should in fact use the same syntax as hosts and email
3619 domains, but in practice they seem to. However, there is little point in
3620 actually causing an error here, because that would no doubt hold up incoming
3621 mail. Instead, I'll just log it. */
3623 for (s
= domain
; *s
!= 0; s
++)
3625 if (!isalnum(*s
) && *s
!= '-' && *s
!= '.' && *s
!= '_')
3627 log_write(0, LOG_MAIN
, "dnslists domain \"%s\" contains "
3628 "strange characters - is this right?", domain
);
3633 /* Check the alternate domain if present */
3635 if (domain_txt
!= domain
) for (s
= domain_txt
; *s
!= 0; s
++)
3637 if (!isalnum(*s
) && *s
!= '-' && *s
!= '.' && *s
!= '_')
3639 log_write(0, LOG_MAIN
, "dnslists domain \"%s\" contains "
3640 "strange characters - is this right?", domain_txt
);
3645 /* If there is no key string, construct the query by adding the domain name
3646 onto the inverted host address, and perform a single DNS lookup. */
3650 if (sender_host_address
== NULL
) return FAIL
; /* can never match */
3651 if (revadd
[0] == 0) invert_address(revadd
, sender_host_address
);
3652 rc
= one_check_dnsbl(domain
, domain_txt
, sender_host_address
, revadd
,
3653 iplist
, bitmask
, match_type
, defer_return
);
3656 dnslist_domain
= string_copy(domain_txt
);
3657 dnslist_matched
= string_copy(sender_host_address
);
3658 HDEBUG(D_dnsbl
) debug_printf("=> that means %s is listed at %s\n",
3659 sender_host_address
, dnslist_domain
);
3661 if (rc
!= FAIL
) return rc
; /* OK or DEFER */
3664 /* If there is a key string, it can be a list of domains or IP addresses to
3665 be concatenated with the main domain. */
3672 uschar keybuffer
[256];
3673 uschar keyrevadd
[128];
3675 while ((keydomain
= string_nextinlist(&key
, &keysep
, keybuffer
,
3676 sizeof(keybuffer
))) != NULL
)
3678 uschar
*prepend
= keydomain
;
3680 if (string_is_ip_address(keydomain
, NULL
) != 0)
3682 invert_address(keyrevadd
, keydomain
);
3683 prepend
= keyrevadd
;
3686 rc
= one_check_dnsbl(domain
, domain_txt
, keydomain
, prepend
, iplist
,
3687 bitmask
, match_type
, defer_return
);
3691 dnslist_domain
= string_copy(domain_txt
);
3692 dnslist_matched
= string_copy(keydomain
);
3693 HDEBUG(D_dnsbl
) debug_printf("=> that means %s is listed at %s\n",
3694 keydomain
, dnslist_domain
);
3698 /* If the lookup deferred, remember this fact. We keep trying the rest
3699 of the list to see if we get a useful result, and if we don't, we return
3700 DEFER at the end. */
3702 if (rc
== DEFER
) defer
= TRUE
;
3703 } /* continue with next keystring domain/address */
3705 if (defer
) return DEFER
;
3707 } /* continue with next dnsdb outer domain */
3712 /* End of verify.c */