[jose] JWK 'use' property

Sergey Beryozkin <sberyozkin@gmail.com> Thu, 11 September 2014 11:20 UTC

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Date: Thu, 11 Sep 2014 12:20:14 +0100
From: Sergey Beryozkin <sberyozkin@gmail.com>
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Subject: [jose] JWK 'use' property
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Hi All,

I'm a bit confused about the purpose of the JWK 'use' property [1].
Specifically, it is not clear to me what does it mean to have a 'public 
signing key' identified with a 'use'='sign'.

AFAIK a public key would be typically used to 'verify' a signature.
When a 'use'='sign' is set, does it mean it is actually 'verify' which 
is implied.

[2] also mentions that 'use' and 'key_ops' should be used together which 
implies to me both properties are kind of conflicting. So why to have 
'use' if 'key_ops' can be sufficient ?

Note I'm just trying to generate some noise :-), I'm curious how either 
of these properties can be used to optimize the storing of keys in JWK 

Thanks, Sergey

[1] https://tools.ietf.org/html/draft-ietf-jose-json-web-key-31#section-4.2
[2] https://tools.ietf.org/html/draft-ietf-jose-json-web-key-31#section-4.3