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Perfect Forward Secrecy in SSH

Perfect Forward Secrecy (PFS) is a property of public-key encryption systems which generate random public keys per session for the purposes of key agreement which are not based on any sort of deterministic algorithm. A compromise of one message cannot lead to the compromise of another message or multiple messages. Twitter, Apache mod_ssh, SSL, TLS, and IPSec all support forward secrecy. According to the referenced Wikipedia article: Forward secrecy is designed to prevent the compromise of a long-term secret key from affecting the confidentiality of past conversations. However, forward secrecy (including perfect forward secrecy) cannot defend against a successful cryptanalysis

Linux UEFI Secure Boot

While Matthew Garrett has been gathering a lot of attention with his blog posts about UEFI Secure Boot, another Red Hat employee, Peter Jones, has been doing excellent work down in the trenches developing a utility (pesign) for securing signing of UEFI binaries on Linux platforms and a setup tool for enrolling your public key(s) in UEFI firmware. Is Secure Boot breakable? Yes, of course, but it is not that easy to do. The technology underlying Secure Boot is battle tested and proven. Here is how it basically works. Assuming you have generated a 2048-bit RSA key, the signing process