mbedtls_asn1_get_bitstring_null: fix rejection of short inputs
Fix improper rejection of bitstrings with length less than 2.
@@ -230,8 +230,13 @@ int mbedtls_asn1_get_bitstring_null( unsigned char **p, const unsigned char *end
if( ( ret = mbedtls_asn1_get_tag( p, end, len, MBEDTLS_ASN1_BIT_STRING ) ) != 0 )
return( ret );
- if( (*len)-- < 2 || *(*p)++ != 0 )
+ if( *len == 0 )
return( MBEDTLS_ERR_ASN1_INVALID_DATA );
+ --( *len );
+
+ if( **p != 0 )
+ return( MBEDTLS_ERR_ASN1_INVALID_DATA );
+ ++( *p );
return( 0 );
}
