Watson Ladd <watsonbl...@gmail.com> writes: >As written supporting this draft requires adopting the encrypt-then-MAC >extension. But there already is a widely implemented secure way to use MACs >in TLS: AES-GCM.
This is there as an option if you want it. Since it offers no length hiding, it's completely unacceptable to some users, for example one protocol uses TLS to communicate monitoring commands to remote gear, they're very short and fixed-length, different for each command, so if you use GCM you may as well be sending plaintext. In addition GCM is incredibly brittle, get the IV handling wrong and you get a complete, catastrophic loss of both integrity and confidentiality. The worst that happens with CBC, even with a complete abuse like using an all-zero IV, is that you drop back to ECB mode. >Likewise, this draft modifies the way the master secret is computed, despite >a widely implemented different solution to the problem, namely the EMS triple >handshake fix. Firstly, that solves an entirely different problem, and secondly I don't recall ever seeing EMS support in any embedded device, it may be widely implemented in Windows and OpenSSL but I don't know how much further it goes. >The use of uncompressed points makes off-curve attacks much easier than with >compressed points. Everything uses uncompressed points at the moment without any problems, and compressed points are patented. >The analysis of TLS 1.3 is just wrong. TLS 1.3 has been far more extensively >analyzed then TLS 1.2. As the rationale points out, the mechanisms in SSL were also very heavily analysed when they were released. It didn't protect the protocol from 20 years of subsequent attacks, which we've leared about over those 20 years of implementation and deployment experience. With TLS 1.3 we have zero implementation and deployment experience. Do you really believe there will never be any attacks on it after it's rolled out? Peter. _______________________________________________ TLS mailing list TLS@ietf.org https://www.ietf.org/mailman/listinfo/tls
