针对DVB条件接收系统的攻击与防御策略研究

Investigation of Attack and Resistance Policy on DVB Conditional Access System

介绍了典型条件接收系统的工作原理,指出了条件接收系统受到的安全威胁主要是来自非授权用户对授权控制信息ECM和授权管理信息EMM的密码学攻击,综合分析了在实际DVB条件接收系统中生成ECM时使用较多的DES加密算法所受到各种攻击,以及生成EMM时使用较多的RSA加密算法所受到各种攻击,重点研究了针对RSA加密算法的计时攻击方法,并提出了针对各种主要加密算法攻击的防御和应对措施。

This paper introduces the structure and operation principle of the typical CAS, and points out that the main security threat the CAS received comes from the unauthorized subscriber＇s cryptography attack to the Entitlement Control Message （ECM） and Entitlement Management Message （EMM）. This paper analyzes synthetically the attacking to the DES encryption arithmetic widely used in the process of forming ECM in the actual CAS of DVB, and the RSA encryption arithmetic widely used in the process of forming EMM in the actual CAS of DVB. The paper emphasizes on the timing attack to the RSA encryption arithmetic, and proposes the corresponding policy of resistance and counter-measure to various kinds of attacking methods.