https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/Recent content in 算法和协议中的安全机制 on 蛇索尼 AidenHugo -- gohugo.iozh-CNshesl-meow@qq.com (佘崧林)shesl-meow@qq.com (佘崧林)Wed, 12 Jun 2019 05:06:21 +0800https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/5.publickey/Wed, 12 Jun 2019 05:06:21 +0800shesl-meow@qq.com (佘崧林)https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/5.publickey/Security is based on the difficulty of some computational hard problems: factorization large integer, discrete algorithm. Diffie-Hellman Key Exchange 用于在两个终端之间共享一个私密的数字： 此时两个终端直接就共享了一个私密信息：$$\displaystyhttps://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/6.securityinfrastructure/Wed, 12 Jun 2019 05:06:21 +0800shesl-meow@qq.com (佘崧林)https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/6.securityinfrastructure/https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/7.establishcommunication/Wed, 12 Jun 2019 05:06:21 +0800shesl-meow@qq.com (佘崧林)https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/7.establishcommunication/https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/3.streamciphers/Sun, 21 Apr 2019 21:26:49 +0800shesl-meow@qq.com (佘崧林)https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/3.streamciphers/Overview Two phases in stream cipher: key initialization phase.(KIA) PRSG running phase. Design princinple Typical stream Ciphers A5/1 in GSM Cipher flow: 上图中，A5/1 部分就是基于一个密钥的随机数生成器，它主要由以下三个部分组成： It uses three LFSRs generating m-sequences of large periodshttps://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/4.block_hash_mac/Sun, 21 Apr 2019 21:26:49 +0800shesl-meow@qq.com (佘崧林)https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/4.block_hash_mac/Block Cipher DES DES stand for Data Encryption Standard. Spectral properties of S-Box: Hadamard transform: $$\displaystyle f(w) = \sum_{x \in F_2^n} (-1)^{f(x) + xw}$$ Avalanche transform: $$\displaystyle A(w) = \sum_{x \in F_2^n} (-1)^{f(x) + f(x + w)}$$ Triple-DES: $$C = E_{K_3} (D_{K_2} (E_{K_1}(M)))$$ or $$C = D_{K_3} (E_{K_2} (D_{K_1}(M)))$$ Encryption Modes: Electronic Codebook (ECB) Mode => Security risks. Cipher Block Chaining (CBC) Mode. Montgomery Ladder A compute algorithm that resisthttps://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/2.prsg/Wed, 27 Mar 2019 12:06:27 +0800shesl-meow@qq.com (佘崧林)https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/2.prsg/Background We focus on the deterministic algorithm: One is linear/non-linear feedback shift registers based on PRSGs. One relies on computation infeasible problems or other types of maths structure. Feedback Shift Register Sequence Feedback shift register (反馈位移寄存器), denotes as FSR： Introduction to FSR: feedback function $$a_{k+n} = f(a_k, a_{k+1}, \cdots, a_{k+n-1})$$ A state diagram of an FSR FSRs withhttps://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/1.introduction/Wed, 27 Feb 2019 00:36:48 +0800shesl-meow@qq.com (佘崧林)https://blog.haitai-social.com/note/%E7%B3%BB%E7%BB%9F%E7%90%86%E8%AE%BA%E8%AF%BE%E7%A8%8B/%E7%AE%97%E6%B3%95%E5%92%8C%E5%8D%8F%E8%AE%AE%E4%B8%AD%E7%9A%84%E5%AE%89%E5%85%A8%E6%9C%BA%E5%88%B6/1.introduction/Terminologies in this Class: Confidentiality, Integrity, Authenticity etc. 安全三要素：保密性、完整性、认证性（真实性） Communication System Security Communication system security is achieved in two aspects: Make each node a trusted platform: robust hardware, validated system software, authorized applications. Protect communications on each link: mutual authentication, key establishment, cipher suite negotiation, failure detection. 课堂