On 10-01-15 18:51, Jonathan K. Bullard wrote: > I just noticed an old (December 2011) blog post by Moxie Marlinspike, > The Cryptographic Doom Principle > <http://www.thoughtcrime.org/blog/the-cryptographic-doom-principle/?> > mentioned > recently on Hacker News <https://news.ycombinator.com/>, and wondered > how the OpenVPN protocol works: in particular, does it "encrypt then > authenticate"?
For the control channel it does whatever your TLS cipher suite does (usually mac-then-encrypt, but with an up-to-date version of your crypto library and having TLS-version negotiation enabled at both ends possibly aead or encrypt-then-mac). For the data channel, which is the most interesting since it is the easiest to influence its traffic as an attacker, OpenVPN uses it's own protocol, which does encrypt-then-mac. So as far as OpenVPN's own crypto goes, we're good. Still, if TLS breaks, everything breaks (okay, there is TLS-auth as a bonus, but that won't always save you either). -Steffan ------------------------------------------------------------------------------ Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net _______________________________________________ Openvpn-users mailing list Openvpn-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-users
