Fix memory leak while parsing some X.509 certs
diff --git a/ChangeLog b/ChangeLog
index 8e74c0b..84420b9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,9 @@
Security
* Lowest common hash was selected from signature_algorithms extension in
TLS 1.2 (found by Darren Bane) (introduced in 1.3.8).
+ * Remotely-triggerable memory leak when parsing some X.509 certificates
+ (server is not affected if it doesn't ask for a client certificate).
+ (Found using Codenomicon Defensics.)
Bugfix
* Support escaping of commas in x509_string_to_names()
@@ -36,6 +39,8 @@
* POLARSSL_MPI_MAX_SIZE now defaults to 1024 in order to allow 8192 bits
RSA keys.
* Accept spaces at end of line or end of buffer in base64_decode().
+ * X.509 certificates with more than one AttributeTypeAndValue per
+ RelativeDistinguishedName are not accepted any more.
= PolarSSL 1.3.8 released 2014-07-11
Security
diff --git a/library/x509.c b/library/x509.c
index 49f7672..941472c 100644
--- a/library/x509.c
+++ b/library/x509.c
@@ -409,58 +409,47 @@
* AttributeType ::= OBJECT IDENTIFIER
*
* AttributeValue ::= ANY DEFINED BY AttributeType
+ *
+ * We restrict RelativeDistinguishedName to be a set of 1 element. This is
+ * the most common case, and our x509_name structure currently can't handle
+ * more than that.
*/
int x509_get_name( unsigned char **p, const unsigned char *end,
x509_name *cur )
{
int ret;
- size_t len;
- const unsigned char *end2;
- x509_name *use;
+ size_t set_len;
+ const unsigned char *end_set;
- if( ( ret = asn1_get_tag( p, end, &len,
+ /*
+ * parse first SET, restricted to 1 element
+ */
+ if( ( ret = asn1_get_tag( p, end, &set_len,
ASN1_CONSTRUCTED | ASN1_SET ) ) != 0 )
return( POLARSSL_ERR_X509_INVALID_NAME + ret );
- end2 = end;
- end = *p + len;
- use = cur;
+ end_set = *p + set_len;
- do
- {
- if( ( ret = x509_get_attr_type_value( p, end, use ) ) != 0 )
- return( ret );
+ if( ( ret = x509_get_attr_type_value( p, end_set, cur ) ) != 0 )
+ return( ret );
- if( *p != end )
- {
- use->next = (x509_name *) polarssl_malloc(
- sizeof( x509_name ) );
-
- if( use->next == NULL )
- return( POLARSSL_ERR_X509_MALLOC_FAILED );
-
- memset( use->next, 0, sizeof( x509_name ) );
-
- use = use->next;
- }
- }
- while( *p != end );
+ if( *p != end_set )
+ return( POLARSSL_ERR_X509_FEATURE_UNAVAILABLE );
/*
* recurse until end of SEQUENCE is reached
*/
- if( *p == end2 )
+ if( *p == end )
return( 0 );
- cur->next = (x509_name *) polarssl_malloc(
- sizeof( x509_name ) );
+ cur->next = (x509_name *) polarssl_malloc( sizeof( x509_name ) );
if( cur->next == NULL )
return( POLARSSL_ERR_X509_MALLOC_FAILED );
memset( cur->next, 0, sizeof( x509_name ) );
- return( x509_get_name( p, end2, cur->next ) );
+ return( x509_get_name( p, end, cur->next ) );
}
/*
diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index 4cec070..c5c4af7 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -750,7 +750,7 @@
x509parse_crt:"30253023a0030201028204deadbeef300d06092a864886f70d0101020500300731053003060013":"":POLARSSL_ERR_X509_INVALID_NAME + POLARSSL_ERR_ASN1_OUT_OF_DATA
X509 Certificate ASN1 (TBSCertificate, issuer, no full following string)
-x509parse_crt:"302b3029a0030201028204deadbeef300d06092a864886f70d0101020500300d310b3009060013045465737400":"":POLARSSL_ERR_X509_INVALID_NAME + POLARSSL_ERR_ASN1_UNEXPECTED_TAG
+x509parse_crt:"302b3029a0030201028204deadbeef300d06092a864886f70d0101020500300d310b3009060013045465737400":"":POLARSSL_ERR_X509_FEATURE_UNAVAILABLE
X509 Certificate ASN1 (TBSCertificate, valid issuer, no validity)
x509parse_crt:"302a3028a0030201028204deadbeef300d06092a864886f70d0101020500300c310a30080600130454657374":"":POLARSSL_ERR_X509_INVALID_DATE + POLARSSL_ERR_ASN1_OUT_OF_DATA