Re: [jose] PBES2-HS256+A128KW: where do salt and iteration count go?

"Manger, James H" <> Wed, 17 July 2013 00:08 UTC

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From: "Manger, James H" <>
To: Richard Barnes <>, Mike Jones <>
Date: Wed, 17 Jul 2013 10:08:21 +1000
Thread-Topic: [jose] PBES2-HS256+A128KW: where do salt and iteration count go?
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Subject: Re: [jose] PBES2-HS256+A128KW: where do salt and iteration count go?
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"kty":"PBKDF2" feels unnecessary, though "kty":"password" would be useful. A key set could have an entry like the following:

 "alg":" PBES2-HS256+A128KW",
 "prompt":"Payment approval PIN",
 "hint":"last 4 digits of \u03C0"

The entry could also have a "password" field holding the actual password.
Mind you, I think mixing public (eg kty, alg) and sensitive (eg hint, password) fields side-by-side in a JSON object is a design guaranteed to lead to security breaches from poor handling.

James Manger

From: Richard Barnes []
Sent: Wednesday, 17 July 2013 9:37 AM
To: Mike Jones
Cc: Matt Miller (mamille2); Manger, James H;
Subject: Re: [jose] PBES2-HS256+A128KW: where do salt and iteration count go?

I was thinking that the "jwk" would be unnecessary.  We could have "hint" at the top level, or just use "kid" for that purpose.


On Tue, Jul 16, 2013 at 7:30 PM, Mike Jones <<>> wrote:
If we move “s” and “c” to being header parameters from the JWK, would we still need the JWK with “kty”:”PBKDF2”?  All that would be left would be the “hint” JWK parameter.