Rationale for Hawk dropping nonces?

[Jan Algermissen]

Hi Eran,

(need to pick your brain again - trying to do that minimally invasive :-)

Did you drop nonces from Hawk out of an 80/20 consideration? Maybe along these lines:

Dropping nonce allows replay attacks but that's ok because sensitive stuff (e.g. placing an order) needs extra protection (HTTPS) anyway and replaying the non-sensitive stuff (e.g. doing a product search) is ok.

Jan

[Eran Hammer]

Probably going to bring nonce support back shortly.

 

I took it out mostly because nonce checking requires some form of persistent storage and almost no one implements it. But it’s easy to put it in, generate it by the client at little to no cost, and ignore or verify by the server on a per-endpoint basis.

 

And while it is true that TLS provides protection against replay, if we were able to blindly trust TLS we would not need Hawk. The point is that we know credentials are going to leak and want to mitigate that by layering our security.

 

EH

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[Jan Algermissen]

Hi Eran,

On Friday, November 30, 2012 4:59:05 PM UTC+1, Eran Hammer wrote:

Probably going to bring nonce support back shortly. 

I took it out mostly because nonce checking requires some form of persistent storage and almost no one implements it. But it’s easy to put it in, generate it by the client at little to no cost, and ignore or verify by the server on a per-endpoint basis.

Is scalability (stateless server) high on the wish-list for OZ? Will server statelessness guide design decisions? Or is that issue out of scope?

 

And while it is true that TLS provides protection against replay, if we were able to blindly trust TLS we would not need Hawk. The point is that we know credentials are going to leak and want to mitigate that by layering our security.

Yep, that's what I expected :-)

Jan