标题： 一种基于量子随机数的改进ChaCha算法 显示英文标题

标题： An Improved ChaCha Algorithm Based on Quantum Random Number

摘要： 由于ChaCha具有高效率和对定时攻击和侧信道攻击强安全性的优点，已被广泛应用于实时通信和数据流场景中。然而，随着人工智能辅助密码分析和量子计算技术的快速发展，ChaCha密码的安全实现面临严峻挑战。为了进一步增强ChaCha密码的安全性，我们提出了一种基于量子随机数的改进变体，即量子随机数增强的ChaCha（QRE-ChaCha）。具体而言，该设计将初始常量与量子随机数进行异或，并在奇数轮次中定期将量子随机数注入选定的状态字以增强扩散性。与原始ChaCha相比，该变体对差分攻击表现出更强的抵抗力，并生成具有统计随机性的密钥流，从而增强了对经典和量子攻击的鲁棒性。为了评估当前ChaCha的安全性和性能，我们的分析分为三个主要部分。首先，我们从量子随机性和攻击测试的角度分析其理论安全性，并采用基于布尔可满足性问题（SAT）的自动化搜索方法进行差分密码分析。其次，我们使用NIST统计测试套件和GM/T 0005-2021随机性测试标准对密码生成的密钥流进行随机性测试。最后，我们通过测量其在不同大小文件上的加密速度来评估其加密和解密性能。根据结果，当前的ChaCha在保持原始ChaCha高效率的同时，显著提高了抵抗差分攻击的能力，其密钥流成功通过了NIST和GM/T 0005-2021标准的统计随机性测试，满足密码应用的要求。 显示英文摘要

摘要： Due to the merits of high efficiency and strong security against timing and side-channel attacks, ChaCha has been widely applied in real-time communication and data streaming scenarios. However, with the rapid development of AI-assisted cryptanalysis and quantum computing technologies, there are serious challenges to the secure implementation of ChaCha cipher. To further strengthen the security of ChaCha cipher, we propose an improved variant based on quantum random numbers, i.e., Quantum Random Number Enhanced ChaCha (QRE-ChaCha). Specifically, the design XORs the initial constants with quantum random numbers and periodically injects quantum random numbers into selected state words during odd rounds to enhance diffusion. Compared with the original ChaCha, the present variant shows stronger resistance to differential attacks and generates a keystream with statistical randomness, thereby offering increased robustness against both classical and quantum attacks. To evaluate the security and performance of the present ChaCha, our analysis proceeds in three main parts. Firstly, we analyze its theoretical security in terms of quantum randomness and attack testing, and conduct differential cryptanalysis with an automated search method based on the Boolean satisfiability problem (SAT). Secondly, we subject the keystream generated by the cipher to randomness tests using the NIST statistical test suite and the GM/T 0005-2021 randomness testing standard. Finally, we assess its encryption and decryption performance by measuring its encryption speed on files of various sizes. According to the results, the present ChaCha is significantly improved to resist differential attacks while maintaining the high efficiency of the original ChaCha cipher, and its keystream successfully passes statistical randomness tests using the NIST and GM/T 0005-2021 standards, meeting cryptographic application requirements.