Re: [Unbearable] Dealing with header injection through reverse proxies
Piotr Sikora <piotrsikora@google.com> Tue, 18 July 2017 09:23 UTC
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From: Piotr Sikora <piotrsikora@google.com>
Date: Tue, 18 Jul 2017 11:23:39 +0200
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To: Brian Campbell <bcampbell@pingidentity.com>
Cc: Eric Rescorla <ekr@rtfm.com>, IETF Tokbind WG <unbearable@ietf.org>, HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: [Unbearable] Dealing with header injection through reverse proxies
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Hey Brian, > I perhaps didn't articulate it well in the meeting yesterday but I'd like to > reiterate that, in my opinion and I don't think I'm alone, it would be very > inappropriate for -tokbind-ttrp to define a one-off mechanism for the origin > server to detect client injection of the headers. The potential problem of > client header injection is not at all unique to the functionality of that > draft so the draft shouldn't define a unique solution. It would be useful if > there were a common standardized mechanism for doing detecting/preventing > client header injection that the -tokbind-ttrp draft could refer to (the > generic solution that Ekr mentions in his [1] seems preferable precisely > because it is generally applicable). In the absence of a generic solution > existing currently, stripping/sanitizing the headers is the de facto means > of dealing with the situation in practice today, is sufficient when properly > implemented, and is normatively required by the text in -tokbind-ttrp. It's > true that, if the reverse proxy is defective/misconfigured, it doesn't fail > safe but in the context of -tokbind-ttrp that failure mode is far from > catastrophic. Such a failure loses the protections afforded by token > binding, which is not ideal, but it is the current state of just about > everything on the web today so it's not *that* bad. I agree. I don't believe that TOKBIND-TTRP draft should be blocked on this. Best regards, Piotr Sikora
- [Unbearable] Dealing with header injection throug… Eric Rescorla
- Re: [Unbearable] Dealing with header injection th… Cantor, Scott
- Re: [Unbearable] Dealing with header injection th… Ted Lemon
- Re: [Unbearable] Dealing with header injection th… John Bradley
- Re: [Unbearable] Dealing with header injection th… Willy Tarreau
- Re: [Unbearable] Dealing with header injection th… Brian Campbell
- Re: [Unbearable] Dealing with header injection th… Piotr Sikora
- Re: [Unbearable] Dealing with header injection th… Piotr Sikora
- Re: [Unbearable] Dealing with header injection th… Piotr Sikora
- Re: [Unbearable] Dealing with header injection th… Leif Johansson
- Re: [Unbearable] Dealing with header injection th… Joseph Salowey
- Re: [Unbearable] Dealing with header injection th… Graham Leggett
- Re: [Unbearable] Dealing with header injection th… Willy Tarreau