基于明文长度的椭圆曲线密码密文构建方法

针对存储椭圆曲线密码加密生成的密文与明文相比需要的存储空间较多的问题,提出了一种基于明文长度的构建椭圆曲线密码密文的方法。首先,该方法通过分析椭圆曲线密码加密运算流程,推导出明文椭圆曲线点的数量决定存储密文椭圆曲线点需要的存储空间。其次,该方法融合明文分割和明文组合的加密模式,建立了信息加密模型;在建立的模型中针对明文分割和明文组合信息加密模式,设计出能够生成最小数量明文椭圆曲线点的明文分割算法和明文组合算法。最后,该方法计算出存储密文椭圆曲线点需要的存储空间,并通过分析决定存储空间需求的影响因素,给出减少生成密文椭圆曲线点数量的解决途径。分析和示例计算表明,与加密单个字符方式相比,应用基于明文分割信息加密模式,存储密文椭圆曲线点占用的存储空间减少了88.2%;应用基于明文组合信息加密模式,存储密文椭圆曲线点占用的存储空间减少了90.2%。研究结果表明,提出的加密方法能够有效地减少生成密文椭圆曲线点的数量,降低存储密文椭圆曲线点对硬件存储空间的需求。

Cipher texts generation method in elliptic curve cryptography based on plaintext length

Since the space for saving cipher texts is more than that for saving plaintexts in elliptic curve cryptography encrypting process, a method of generating cipher texts which utilized elliptic curve cryptography based on plaintext length was proposed. Firstly, by analyzing encrypting operation process of elliptic curve encryption, it was deduced that the space for cipher texts of elliptic curve points was decided by the number of plaintexts in elliptic curve points. Secondly, by fusing the encrypting patterns based on segmentation and combination plaintexts, an encrypting model was constructed, and plaintext segmentation algorithm and plaintext combination algorithm were put forward to generate the minimum number of elliptic curve points. Finally, the demanded space for saving cipher texts in elliptic curve points was calculated, and the solutions for reducing the number of cipher texts in elliptic curve points were given. By the analysis and calculation, it is shown that the space of cipher text elliptic curve points decreases 88.2% by segmentation plaintexts and decreases 90.2% by combination plaintexts. The results show the method can decrease the number of cipher texts in elliptic curve points and the storage space demand for hardware.