blob: e1c8052578ecdd06738723bedbc31cf9c31f00d1 [file] [log] [blame]
From 8259daad7242ab2af8731681177ef7e948a15ece Mon Sep 17 00:00:00 2001
From: Mark Andrews <marka@isc.org>
Date: Mon, 16 Nov 2015 13:12:20 +1100
Subject: [PATCH] 4260. [security] Insufficient testing when parsing a
message allowed records with an incorrect class to be
be accepted, triggering a REQUIRE failure when those
records were subsequently cached. (CVE-2015-8000) [RT
#4098]
(cherry picked from commit c8821d124c532e0a65752b378f924d4259499fd3)
(cherry picked from commit 3a4c24c4a52d4a2d21d2decbde3d4e514e27d51c)
Upstream-Status: Backport
https://source.isc.org/cgi-bin/gitweb.cgi?p=bind9.git;a=commit;h=8259daad7242ab2af8731681177ef7e948a15ece
CVE: CVE-2015-8000
Signed-off-by: Armin Kuster <akuster@mvista.com>
---
CHANGES | 5 +++++
bin/tests/system/start.pl | 5 ++++-
doc/arm/notes.xml | 9 +++++++++
lib/dns/include/dns/message.h | 13 +++++++++++--
lib/dns/message.c | 45 ++++++++++++++++++++++++++++++++++++++-----
lib/dns/resolver.c | 9 +++++++++
lib/dns/xfrin.c | 2 ++
7 files changed, 80 insertions(+), 8 deletions(-)
Index: bind-9.10.2-P4/bin/tests/system/start.pl
===================================================================
--- bind-9.10.2-P4.orig/bin/tests/system/start.pl
+++ bind-9.10.2-P4/bin/tests/system/start.pl
@@ -68,6 +68,7 @@ my $NAMED = $ENV{'NAMED'};
my $LWRESD = $ENV{'LWRESD'};
my $DIG = $ENV{'DIG'};
my $PERL = $ENV{'PERL'};
+my $PYTHON = $ENV{'PYTHON'};
# Start the server(s)
@@ -213,7 +214,9 @@ sub start_server {
$pid_file = "lwresd.pid";
} elsif ($server =~ /^ans/) {
$cleanup_files = "{ans.run}";
- if (-e "$testdir/$server/ans.pl") {
+ if (-e "$testdir/$server/ans.py") {
+ $command = "$PYTHON ans.py 10.53.0.$' 5300";
+ } elsif (-e "$testdir/$server/ans.pl") {
$command = "$PERL ans.pl";
} else {
$command = "$PERL $topdir/ans.pl 10.53.0.$'";
Index: bind-9.10.2-P4/doc/arm/notes.xml
===================================================================
--- bind-9.10.2-P4.orig/doc/arm/notes.xml
+++ bind-9.10.2-P4/doc/arm/notes.xml
@@ -62,6 +62,15 @@
<itemizedlist>
<listitem>
<para>
+ Insufficient testing when parsing a message allowed
+ records with an incorrect class to be be accepted,
+ triggering a REQUIRE failure when those records
+ were subsequently cached. This flaw is disclosed
+ in CVE-2015-8000. [RT #4098]
+ </para>
+ </listitem>
+ <listitem>
+ <para>
An incorrect boundary check in the OPENPGPKEY rdatatype
could trigger an assertion failure. This flaw is disclosed
in CVE-2015-5986. [RT #40286]
Index: bind-9.10.2-P4/lib/dns/include/dns/message.h
===================================================================
--- bind-9.10.2-P4.orig/lib/dns/include/dns/message.h
+++ bind-9.10.2-P4/lib/dns/include/dns/message.h
@@ -15,8 +15,6 @@
* PERFORMANCE OF THIS SOFTWARE.
*/
-/* $Id$ */
-
#ifndef DNS_MESSAGE_H
#define DNS_MESSAGE_H 1
@@ -221,6 +219,8 @@ struct dns_message {
unsigned int free_saved : 1;
unsigned int sitok : 1;
unsigned int sitbad : 1;
+ unsigned int tkey : 1;
+ unsigned int rdclass_set : 1;
unsigned int opt_reserved;
unsigned int sig_reserved;
@@ -1400,6 +1400,15 @@ dns_message_buildopt(dns_message_t *msg,
* \li other.
*/
+void
+dns_message_setclass(dns_message_t *msg, dns_rdataclass_t rdclass);
+/*%<
+ * Set the expected class of records in the response.
+ *
+ * Requires:
+ * \li msg be a valid message with parsing intent.
+ */
+
ISC_LANG_ENDDECLS
#endif /* DNS_MESSAGE_H */
Index: bind-9.10.2-P4/lib/dns/message.c
===================================================================
--- bind-9.10.2-P4.orig/lib/dns/message.c
+++ bind-9.10.2-P4/lib/dns/message.c
@@ -439,6 +439,8 @@ msginit(dns_message_t *m) {
m->free_saved = 0;
m->sitok = 0;
m->sitbad = 0;
+ m->tkey = 0;
+ m->rdclass_set = 0;
m->querytsig = NULL;
}
@@ -1091,13 +1093,19 @@ getquestions(isc_buffer_t *source, dns_m
* If this class is different than the one we already read,
* this is an error.
*/
- if (msg->state == DNS_SECTION_ANY) {
- msg->state = DNS_SECTION_QUESTION;
+ if (msg->rdclass_set == 0) {
msg->rdclass = rdclass;
+ msg->rdclass_set = 1;
} else if (msg->rdclass != rdclass)
DO_FORMERR;
/*
+ * Is this a TKEY query?
+ */
+ if (rdtype == dns_rdatatype_tkey)
+ msg->tkey = 1;
+
+ /*
* Can't ask the same question twice.
*/
result = dns_message_find(name, rdclass, rdtype, 0, NULL);
@@ -1241,12 +1249,12 @@ getsection(isc_buffer_t *source, dns_mes
* If there was no question section, we may not yet have
* established a class. Do so now.
*/
- if (msg->state == DNS_SECTION_ANY &&
+ if (msg->rdclass_set == 0 &&
rdtype != dns_rdatatype_opt && /* class is UDP SIZE */
rdtype != dns_rdatatype_tsig && /* class is ANY */
rdtype != dns_rdatatype_tkey) { /* class is undefined */
msg->rdclass = rdclass;
- msg->state = DNS_SECTION_QUESTION;
+ msg->rdclass_set = 1;
}
/*
@@ -1256,7 +1264,7 @@ getsection(isc_buffer_t *source, dns_mes
if (msg->opcode != dns_opcode_update
&& rdtype != dns_rdatatype_tsig
&& rdtype != dns_rdatatype_opt
- && rdtype != dns_rdatatype_dnskey /* in a TKEY query */
+ && rdtype != dns_rdatatype_key /* in a TKEY query */
&& rdtype != dns_rdatatype_sig /* SIG(0) */
&& rdtype != dns_rdatatype_tkey /* Win2000 TKEY */
&& msg->rdclass != dns_rdataclass_any
@@ -1264,6 +1272,16 @@ getsection(isc_buffer_t *source, dns_mes
DO_FORMERR;
/*
+ * If this is not a TKEY query/response then the KEY
+ * record's class needs to match.
+ */
+ if (msg->opcode != dns_opcode_update && !msg->tkey &&
+ rdtype == dns_rdatatype_key &&
+ msg->rdclass != dns_rdataclass_any &&
+ msg->rdclass != rdclass)
+ DO_FORMERR;
+
+ /*
* Special type handling for TSIG, OPT, and TKEY.
*/
if (rdtype == dns_rdatatype_tsig) {
@@ -1377,6 +1395,10 @@ getsection(isc_buffer_t *source, dns_mes
skip_name_search = ISC_TRUE;
skip_type_search = ISC_TRUE;
issigzero = ISC_TRUE;
+ } else {
+ if (msg->rdclass != dns_rdataclass_any &&
+ msg->rdclass != rdclass)
+ DO_FORMERR;
}
} else
covers = 0;
@@ -1625,6 +1647,7 @@ dns_message_parse(dns_message_t *msg, is
msg->counts[DNS_SECTION_ADDITIONAL] = isc_buffer_getuint16(source);
msg->header_ok = 1;
+ msg->state = DNS_SECTION_QUESTION;
/*
* -1 means no EDNS.
@@ -3706,3 +3729,15 @@ dns_message_buildopt(dns_message_t *mess
dns_message_puttemprdatalist(message, &rdatalist);
return (result);
}
+
+void
+dns_message_setclass(dns_message_t *msg, dns_rdataclass_t rdclass) {
+
+ REQUIRE(DNS_MESSAGE_VALID(msg));
+ REQUIRE(msg->from_to_wire == DNS_MESSAGE_INTENTPARSE);
+ REQUIRE(msg->state == DNS_SECTION_ANY);
+ REQUIRE(msg->rdclass_set == 0);
+
+ msg->rdclass = rdclass;
+ msg->rdclass_set = 1;
+}
Index: bind-9.10.2-P4/lib/dns/resolver.c
===================================================================
--- bind-9.10.2-P4.orig/lib/dns/resolver.c
+++ bind-9.10.2-P4/lib/dns/resolver.c
@@ -7309,6 +7309,8 @@ resquery_response(isc_task_t *task, isc_
goto done;
}
+ dns_message_setclass(message, fctx->res->rdclass);
+
if ((options & DNS_FETCHOPT_TCP) == 0) {
if ((options & DNS_FETCHOPT_NOEDNS0) == 0)
dns_adb_setudpsize(fctx->adb, query->addrinfo,
@@ -7391,6 +7393,13 @@ resquery_response(isc_task_t *task, isc_
&dns_master_style_comment,
ISC_LOG_DEBUG(10),
fctx->res->mctx);
+
+ if (message->rdclass != fctx->res->rdclass) {
+ resend = ISC_TRUE;
+ FCTXTRACE("bad class");
+ goto done;
+ }
+
/*
* Process receive opt record.
*/
Index: bind-9.10.2-P4/lib/dns/xfrin.c
===================================================================
--- bind-9.10.2-P4.orig/lib/dns/xfrin.c
+++ bind-9.10.2-P4/lib/dns/xfrin.c
@@ -1225,6 +1225,8 @@ xfrin_recv_done(isc_task_t *task, isc_ev
msg->tsigctx = xfr->tsigctx;
xfr->tsigctx = NULL;
+ dns_message_setclass(msg, xfr->rdclass);
+
if (xfr->nmsg > 0)
msg->tcp_continuation = 1;
Index: bind-9.10.2-P4/CHANGES
===================================================================
--- bind-9.10.2-P4.orig/CHANGES
+++ bind-9.10.2-P4/CHANGES
@@ -1,4 +1,9 @@
- --- 9.10.2-P4 released ---
+4260. [security] Insufficient testing when parsing a message allowed
+ records with an incorrect class to be be accepted,
+ triggering a REQUIRE failure when those records
+ were subsequently cached. (CVE-2015-8000) [RT #4098]
+
+ --- 9.10.2-P4 released ---
4170. [security] An incorrect boundary check in the OPENPGPKEY
rdatatype could trigger an assertion failure.