Re: [Unbearable] Dealing with header injection through reverse proxies
Piotr Sikora <piotrsikora@google.com> Tue, 18 July 2017 09:20 UTC
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From: Piotr Sikora <piotrsikora@google.com>
Date: Tue, 18 Jul 2017 11:20:16 +0200
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To: Willy Tarreau <w@1wt.eu>
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 Willy, > What I've seen and used was slightly different : > 1) proxies unconditionally remove the header field > 2) proxies unconditionally add the new header field even with no > certificate > 3) servers verify that there is exactly one header field > > This way even if step 1 above fails (eg: usual typo in the rule needed > to strip the header field which nobody notices since nobody injects > such a field name), step 2 ensures that any injection will be detected > in step 3. This is exactly what the current draft suggests and what EKR objects, because misconfigured proxy that doesn't know about "X-Client-Certificate" won't execute steps 1-3 for the "X-Client-Certificate" header. 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