基于QC-MDPC码公钥密码方案下反映攻击的对策

基于中密度准循环奇偶校验码(QC-MDPC)的McEliece公钥密码方案已被验证具有良好的性能特征,其密钥量较少、算法复杂度较低.但目前存在一种密钥恢复攻击对该方案的安全性产生威胁,攻击者利用特定的错误图样生成密文并进行发送,来获取接收者译码是否成功的反应,从而破译出该方案的私钥.为应对此反应攻击,提出了可能的解决方案.该方案将差错控制理论中的自动重传请求(ARQ)与伪随机序列结合,消除了反馈信息的有效性.仿真结果表明,提出的方案能有效抵抗此攻击.最后对提出的方案与各类抗击方案进行了比较,并分析了其未来改进方向.

Countermeasure of reaction attack on QC-MDPC code based PKC

The quasi-cyclic medium-density parity-check(QC-MDPC) code based McEliece public key cryptography(PKC) has good performance characteristics: both the key size and the algorithm complexity of the scheme are low. However, a key recovery attack can crack the scheme against its security. The attacker can collect reaction information of the decoding failure from the receiver by adding specific error patterns to the massage, then somehow reconstruct the secret key. To copy with this attack, this paper proposed some possible countermeasure. The countermeasure combined the automatic repeat-request(ARQ) with pseudo-random sequence to eliminate the validity of feedback information. The simulation results show that the countermeasure can effectively resist this attack. Finally, this paper compared the difference between the proposed countermeasure and other schemes, and analyzed its future improvement direction.