RFR: 8271566: DSA signature length value is not accurate in P11Signature [v2]

[Valerie Peng]

On Fri, 13 Aug 2021 17:11:45 GMT, Martin Balao <mbalao at openjdk.org> wrote:

>> As described in JDK-8271566 [1], this patch proposal is intended to fix a problem that arises when using DSA keys that have a 256-bits (or larger) G parameter for signatures (either signing or verifying). There were some incorrect assumptions and hard-coded length values in the code before. Please note that, for example, the tuple (2048, 256) for DSA is valid according to FIPS PUB 186-4.
>> 
>> Beyond the specific issues in signatures, I decided to provide a broader solution and enable key parameter retrieval for other key types (EC, DH) when possible. This is, when the key is not sensitive. One thing that I should note here is that token keys (those that have the CKA_TOKEN attribute equal to 'true') are considered sensitive in this regard, at least by the NSS Software Token implementation. I don't have access to other vendor implementations but if there is any concern, we can adjust the constraint to NSS-only. However, I'm not sure which use-case would require to get private keys out of a real token, weakening its security. I'd be more conservative here and not query the values if not sure that it will succeed.
>> 
>> No regressions found in jdk/sun/security/pkcs11. A new test added: LargerDSAKey.
>> 
>> --
>> [1] - https://bugs.openjdk.java.net/browse/JDK-8271566
>
> Martin Balao has updated the pull request incrementally with one additional commit since the last revision:
> 
>   P11Key static inner classes refactorings.

Hmm, thinking more about "internal"/"opaque", given this is naming for the parent, maybe "internal" is more correct. The non-sensitive keys are encapsulated by the children classes and is still an instance of the parent. If you name the parent class w/ "opaque" suffix, it looks misleading/confusing. The opaqueness is implied by the implementation instead of the properties of the objects.

-------------

PR: https://git.openjdk.java.net/jdk/pull/4961