W3C home > Mailing lists > Public > ietf-http-wg@w3.org > July to September 2012

Re: Response to HTTP2 expresions of interest

From: James M Snell <jasnell@gmail.com>
Date: Fri, 13 Jul 2012 11:36:03 -0700
Message-ID: <CABP7Rbeg-1+Pmdj-AHGYX7fM4X-EVC06amixq7bQzPnYrYkeyw@mail.gmail.com>
To: Poul-Henning Kamp <phk@phk.freebsd.dk>
Cc: Tim Bray <tbray@textuality.com>, Phillip Hallam-Baker <hallam@gmail.com>, "ietf-http-wg@w3.org Group" <ietf-http-wg@w3.org>
Sounds like we're generally in agreement on most aspects then. I agree
that TLS would not be strictly necessary if we have effective
stream-level security, and I definitely agree that a session
identifier at the stream-level would be highly beneficial. In the
scheme I described, sending a SYN_STREAM with the host and session-id
ONLY, in clear-text, and then encrypting subsequent data frames on the
stream, including the request-uri in an encrypted HEADERS frame,
SHOULD provide for the overwhelming majority of cases. As I said, if a
particular intermediary needs to perform request-uri based routing and
the request-uri is not included in the SYN_STREAM, it has the option
of rejecting the stream, in which case the sender can choose it's next
course of action.

Like I said, it appears to me that we are in agreement but if I am
misreading it, please let me know :-)

- James

On Fri, Jul 13, 2012 at 11:21 AM, Poul-Henning Kamp <phk@phk.freebsd.dk> wrote:
> In message <CABP7RbcVOEfnzg1A+x8NsOu+Gp2OtnHnVvWmLyQUM+QUMLNsUw@mail.gmail.com>
> , James M Snell writes:
>
>>Definitely a tricky thing here because of the competing interests and
>>requirements at play. Transport-layer secure provides the necessary
>>protection against snoopers but makes the efficient routing and
>>handling of the communication via intermediaries far more difficult.
>
> I still don't agree.
>
> The envelope is where you write who you want your adversary to think
> you are communicating with.
>
> This may or may not be who you actually are communicating with.
>
> TLS communication today already have an envelope consisting of
> IP# + TCP port numbers, and unless your adversary is totally
> incompetent, he also has the DNS lookup that gave you that IP#.
>
> QED: Putting the "Host:" in the HTTP envelope does not leak any
> information your adversary doesn't already have or can guess.
>
> Even if we stopped here, it would be a major benefit over TLS
> in terms of enabling websites to roll out protection for their
> customers.
>
> To make it better, we need to add a session identifier, but today
> we pretend HTTP is stateless so we don't have one (so people
> hack it with cookies).
>
> Finally, to do what people do today we would need to include the
> URI, but that is by far the most troublesome of the three fields.
>
> I belive, but it should be seriously investigated, that if we add
> a session-concept to HTTP2, the envelope would just need to be Host:
> + session-nonce.
>
> In difference from TLS, that would allow us to mix protected and
> unprotected traffic on the same TCP connection, thus avoiding
> the extra TCP for protection upgrade, and making life much
> easier and efficient for proxies.
>
> It also means that you do not need to put your certificate on
> the HTTP router/load-balancer, but can put it on the specific
> webservers which host the protected stuff.
>
> SSL/TLS was a quick hack to protect HTTP, one of the far too
> many quick hacks in HTTP world.  We should try to eliminate
> them.
>
> --
> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
> phk@FreeBSD.ORG         | TCP/IP since RFC 956
> FreeBSD committer       | BSD since 4.3-tahoe
> Never attribute to malice what can adequately be explained by incompetence.
Received on Friday, 13 July 2012 18:36:51 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Friday, 13 July 2012 18:36:57 GMT