Tag Archives: cryptography

Libgcrypt 與 GnuPG 的安全性問題

在「Security fixes for Libgcrypt and GnuPG 1.4 [CVE-2016-6316]」這邊看到這個歷史悠久的 bug: Felix Dörre and Vladimir Klebanov from the Karlsruhe Institute of Technology found a bug in the mixing functions of Libgcrypt's random number generator: An attacker who obtains 4640 bits from the … Continue reading

Posted in Computer, Murmuring, Security, Software | Tagged , , , , , , , , , , , | Leave a comment

Google Chrome 引入 CECPQ1,開始測試 Post-Quantum Cryptography

Quantum Computer 對現有密碼學的衝擊很大,像是 RSA 演算法是基於「質因數分解」的難題而架構出來的系統,在 Quantum Computer 上存在有效率的演算法,也就是 Shor's algorithm。 雖然 Quantum Computer 在技術上還沒辦法對現有演算法造成有效的攻擊,但已經有人提出新的演算法來對抗,而 Google 打算在 Google Chrome 裡面引入測試:「Experimenting with Post-Quantum Cryptography」。 Google 也特別說明了,他們不希望這個實驗最後變成 de-facto standard (借測轉出貨的概念),而是希望當作一個開頭,希望之後可以用更好的標準換掉: We explicitly do not wish to make our selected post-quantum algorithm a de-facto … Continue reading

Posted in Browser, Computer, GoogleChrome, Murmuring, Network, Security, Software, WWW | Tagged , , , , , , , | Leave a comment

2015 年的 Turing Award 由 Whitfield Diffie 與 Martin E. Hellman 獲得

從紐約時報看到今年的 Turing Award 由 Whitfield Diffie 與 Martin E. Hellman 獲得:「Cryptography Pioneers Win Turing Award」。在 Turing Award 官網上也可以看到對應的說明。 Diffie–Hellman key exchange 是全世界第一個 (1976 年) 在公開頻道上建立 shared secret 的演算法,直到現在都還廣泛的被使用,可以防禦被動式的監聽攻擊: The Diffie–Hellman key exchange method allows two parties that have no prior … Continue reading

Posted in Computer, Murmuring, Network, Science, Security | Tagged , , , , , , , , , , , | Leave a comment

荷蘭政府捐贈五十萬歐元給 OpenSSL

在一堆政府想要立法放後門進系統的情況下,荷蘭政府則反對這樣的想法,並且決定捐贈五十萬歐元 (目前約五十四萬美金) 給 OpenSSL:「Dutch govt says no to backdoors, slides $540k into OpenSSL without breaking eye contact」: The Dutch government has formally opposed the introduction of backdoors in encryption products. A government position paper, published by the Ministry of Security … Continue reading

Posted in Computer, Murmuring, Network, Political, Social | Tagged , , , , | Leave a comment

OpenSSL 的 ECDH 中,224 bits 速度比 160/192 bits 快的原因

跑 openssl speed ecdh 的時候發現很特別的現象: Doing 160 bit ecdh's for 10s: 40865 160-bit ECDH ops in 9.99s Doing 192 bit ecdh's for 10s: 34169 192-bit ECDH ops in 9.99s Doing 224 bit ecdh's for 10s: 60980 224-bit ECDH ops in … Continue reading

Posted in Computer, Murmuring, Network, Security, Software, WWW | Tagged , , , , , , , , , , , , , , , | Leave a comment