[8u] RFR 8147502: Digest is incorrectly truncated for ECDSA signatures when the bit length of n is less than the field size

[Andrew John Hughes]

On 08/08/2019 20:40, Martin Balao wrote:
> Hi,
> 
> I'd like to request a review for the jdk8u backport of 8147502 [1]:
> 
>  *
> http://cr.openjdk.java.net/~mbalao/webrevs/8147502/8147502.webrev.jdk8u.jdk.00/
> 
> Changes:
> 
>  * SignatureDigestTruncate.java
>   * Import of jdk.testlibrary.Convert
>   * @library and @build jtreg tags
>   * Backport of Convert.java
>   * Test algorithm (changes to one with jdk8u support)
>    * I've verified that the signature gets truncated with this algorithm
> debugging the libsunec.so code
>   * Test expected value
>    * Verified with BouncyCastle
>     * The curve is unsupported in NSS since 2006 (NSS 3.10)
>    * I've also compared the patch against the NSS library
> 
> Patch and copyright changes were also needed.
> 
> SignatureDigestTruncate test passed.
> 
> Thanks,
> Martin.-
> 
> --
> [1] - https://bugs.openjdk.java.net/browse/JDK-8147502
> 

Bringing Convert.java in here is ok because we can't backport the
feature changeset "8171277: Elliptic Curves for Security in Crypto",
but, in cases like this, please explain why you have chosen to include
additional files/hunks beyond the original changes, so reviewers don't
have to duplicate the work of finding out the source of these changes.

Approved.

Thanks,
-- 
Andrew :)

Senior Free Java Software Engineer
Red Hat, Inc. (http://www.redhat.com)

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