Restrict HTTP/2 connections to AEAD ciphers only

[codefromthecrypt]

HTTP/2 Draft 13 restricts TLS cipher suites, and requires support of [TLS-ECDHE] with P256 [FIPS186].

http://tools.ietf.org/html/draft-ietf-httpbis-http2-14#section-9.2.2

implementations of HTTP/2 that use
   TLS 1.2 MUST support TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
   [TLS-ECDHE] with P256 [FIPS186].

[codefromthecrypt]

The requirement is in flux. Summary so far seems either TLS 1.2 where !isBlock() && !isStream() or TLS 1.3

Let's hold off until next draft (15) before addressing this.

[swankjesse]

TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 isn't available on any currently-shipping Android device. It is available in the upcoming Android 5.0, however. This is bad news for HTTP/2 on Android KitKat, for example.

[swankjesse]

Punting to 2.2.

[swankjesse]

I'm not going to take further action here. We offer HTTP/2-capable ciphers, and HTTP/2 incapable ciphers. If the server incorrectly negotiates a non-HTTP/2 cipher suite and the HTTP/2 protocol, we'll do HTTP/2. This isn't perfect, but it's simple.

[swankjesse]

(alternately we'd need to kill the socket and renegotiate TLS, disabling ALPN. I don't think it's worth the effort).

[codefromthecrypt]

Makes sense