It's also worth noting that this is a proposal. You didn't actually make this mistake yourself but I do want to highlight it: the HTTP WG is not yet discussing this as anything more than a suggestion (see http://lists.w3.org/Archives/Public/ietf-http-wg/2014JanMar/... ). If you are worried about this sort of proposal becoming a draft, I highly recommend you join the working group and keep an eye on the proxy discussions.
This will easily allow the carriers to perform their duty of Lawful Interception
* get an alert when going to e.g. www.google.com as the carrier tries to hijack the session with a fake certificate.
* the carrier have their own versions of libraries/browsers/etc. installed on the phone that disables certificate checks/alerts that would pop up when they hijack a session.
* the carrier have actually gotten hold of a certificate for www.google.com - which I'm sure is doable, but harder, and is thus able to perform a successful mitm attack.
With this approach, the carrier just needs to generate their own certificate, install it on the phone they sell, and can proxy any service they want without user alerts. A significant lower entry bar.
This is simple on the client and avoids any security warnings. It's supported in quite a few firewalls and even squid, so it would be very easy for a carrier to roll out tomorrow if they needed to.
Even they don't want to, they will probably have to after a subpoena. While if you don't implement this and other backdoors to the protocol, you won't be able to do it. At least not transparently.
uers should be made aware that, different than end-to-end HTTPS, the achievable security level is now also dependent on the security features/capabilities of the proxy as to what cipher suites it supports, which root CA certificates it trusts, how it checks certificate revocation status, etc. Users should also be made aware that the proxy has visibility to the actual content they exchange with Web servers, including personal and sensitive information.
Now the question is, did you???
I've seen the link[2] you posted and I didn't find ANYWHERE the part where it specifically talks about HTTP and not HTTPS. There's even the above part explaining making things even more complicated...
[1] http://tools.ietf.org/html/draft-loreto-httpbis-trusted-prox...
[2] http://hillbrad.typepad.com/blog/2014/02/trusted-proxies-and...
ps. I really did read them both, I just tend to be a little strong-opinionated.
Any situation in which someone can force your machine to trust one of these proxies is a situation when they had administrator access to your machine anyway, and in that situation you're already screwed.
Would it kill HN to actually read one of these specs instead of just whining about it?