A new draft proposal at the Internet Engineering Task Force by Phillip Hallam-Baker sets out a work program to harden the Internet against Prism-style surveillance. It's a long but fascinating read, and it's been nicely summarized by ParityNews's Ravi Mandalia, who highlights the proposal's emphasis on Perfect Forward Secrecy and strong crypto by default. Last week, I posted John Gilmore's firsthand account of NSA sabotage of a IETF standard; it will be interesting to see how the NSA engages with this process.
Baker starts off by listing out the attack degree including he likes of information / content disclosure, meta-data analysis, traffic analysis, denial of service attacks and protocol exploits. The author than describes the different capabilities of an attacker and the ways in which an attack can be carried out – passive observation, active modification, cryptanalysis, cover channel analysis, lawful interception, Subversion or Coercion of Intermediaries among others.
Baker then highlights the controls that may be used to defend against the attacks including use of Perfect Forward Secrecy which tends to dramatically increase the cost involved with an attack; use of strong cryptography as a control against passive attacks; use of dual-layered public key exchange “using the credentials of the parties to negotiate a temporary key which is in turn used to derive the symmetric session key used for communications” among others.
The draft lists the final control as policy, audit and transparency; however, it notes that this area is “the most underdeveloped area of internet security to date.”
IETF floats draft PRISM-proof security considerations [Ravi Mandalia/Parity News]