Re: Breaking up DSA signature

Jan Luehe (luehe@laguna.eng.sun.com)
Tue, 8 Jun 1999 17:14:19 -0700 (PDT)

Message-Id: <199906090014.RAA28894@laguna.eng.sun.com>
Date: Tue, 8 Jun 1999 17:14:19 -0700 (PDT)
From: Jan Luehe <luehe@laguna.eng.sun.com>
Subject: Re: Breaking up DSA signature
To: java-security@java.sun.com, joakley@us.ibm.com

Judy:

There is no public API for doing this.
The byte array returned by Signature.sign()
represents an ASN.1 SEQUENCE containing
"r" and "s" (in the case of DSA).

You have to decode that SEQUENCE yourself if
you want to retrieve "r" and "s" as separate
values.

Jan

> I am generating a DSA signature using Signature.sign(). I need to extract the
> two parts of the signature (r and s). I have searched most of the afternoon
and
> can find no way to do this in the JCA. Do you know if there is any way
> provided? Thanks!!
>
> Judy Oakley
> IBM Payment Suite Development
> A good name is to be chosen rather than great riches. --Proverbs 22:1
>
>