On 3/26/2022 11:05 AM, xueleifan(XueleiFan) wrote:
Hi Anders,
I would like to have look at the COSE/JOSE specs. If it is convenient to you,
any suggestions about where I could start from? RFC 8812? Do you know where
(areas and products) the COSE/JOSE specs are used in practice?
Thanks,
Xuelei
Hi Xuelei -
Just for clarification - JOSE/COSE are data description languages with
specific provisions for encoding various type of cryptographic key
material. E.g. think ASN1 ~= JOSE or COSE and the RFC's that Anders is
pointing you at as approximately equal to PKCS8 and X.509 plus the key
type specific stuff (e.g. PKCS1 for RSA key encodings, X9.63 for EC key
encodings, later IETF RFCs for newer encodings).
This isn't about math so much as it is about encodings.
Mike
On Mar 25, 2022, at 11:56 AM, Anders Rundgren <anders.rundgren....@gmail.com>
wrote:
Hi Michael & the JDK crypto team,
Although it might be cool writing a JEP it is not really my job. There are
also multiple ways of addressing this issue.
BTW, the COSE/JOSE folks who are about to introduce new algorithms want to
overload RFC 8037 which defines a key type OKP.
I'm not in favor of this idea since breaks existing OKP code.
I'm suggesting that each new crypto system should get its own name space and
thus long-term corresponding Java interfaces.
Since this is happening NOW and there is no turning back, it would be useful to
get some early feedback from the JDK folks. In fact, this is the origin of
this request.
It seems that nobody representing JDK crypto is involved in COSE/JOSE.
Thanx,
Anders
On 2022-03-25 18:23, Michael StJohns wrote:
On 3/25/2022 12:33 PM, Anders Rundgren wrote:
On 2022-03-25 17:12, Anthony Scarpino wrote:
When you say "construct and EC key", do you mean creating an EC key from
an existing set of values via PKCS8 or X509 encoding? Or are you
talking about EC key generation?
I was talking about creating keys from parameter data supplied by for
example JOSE:
{
"kty": "EC",
"crv": "P-256",
"x": "6BKxpty8cI-exDzCkh-goU6dXq3MbcY0cd1LaAxiNrU",
"y": "mCbcvUzm44j3Lt2b5BPyQloQ91tf2D2V-gzeUxWaUdg"
}
Apparently this particular issue have solution (as Michael StJohns
showed), although it is not particularity intuitive as well as
undocumented.
Another take on this issue:
https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/security/Key.html#getEncoded()
"Returns the key in its primary encoding format, or null if this key
does not support encoding"
With COSE/JOSE there is no longer an obvious primary encoding format.
Of course there is. You may not like that it's not COSE or JOSE, but
the encoding spec remains as is and 10s of 1000s of implementations that
use that encoding would be annoyed if you tried to claim a new "primary
encoding format".
The SubjectPublicKeyInfo encoding for PublicKeys, the PKCS8 encoding for
private keys, and RAW encoding for SecretKeys is what's there and I'm
pretty sure won't change. I occasionally wished for a getEncoded()
method that took an encoding type as an argument (e.g.
getEncoded("bareXY") or some such), but that's not in the API.
What I'd suggest is that you write a JEP for adding EncodedKeySpec
classes for COSE and JOSE to the API. I'd probably also add a
GenericKeyEncodingSpec class. That should be simple enough as a first step.
The second step would be to write and contribute a Jose and Cose
KeyFactory implementation that uses those classes.
As I noted, it should be possible to externalize any preferred encoding
by using the getKeySpec method of KeyFactory rather than just the key
types default encoding.
Later, Mike
Anders
Tony
