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The Bouncy Castle Java APIs for CMS, PKCS, EAC, TSP, CMP, CRMF, OCSP, and certificate generation. This jar contains APIs for JDK 1.5 and up. The APIs can be used in conjunction with a JCE/JCA provider such as the one provided with the Bouncy Castle Cryptography APIs.

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package org.bouncycastle.crypto.modes.kgcm;

public class Tables16kKGCMMultiplier_512
    implements KGCMMultiplier
{
    private long[][] T;

    public void init(long[] H)
    {
        if (T == null)
        {
            T = new long[256][KGCMUtil_512.SIZE];
        }
        else if (KGCMUtil_512.equal(H, T[1]))
        {
            return;
        }

        // T[0] = 0

        // T[1] = H
        KGCMUtil_512.copy(H, T[1]);

        for (int n = 2; n < 256; n += 2)
        {
            // T[2.n] = x.T[n]
            KGCMUtil_512.multiplyX(T[n >> 1], T[n]);

            // T[2.n + 1] = T[2.n] + T[1]
            KGCMUtil_512.add(T[n], T[1], T[n + 1]);
        }
    }

    public void multiplyH(long[] z)
    {
        long[] r = new long[KGCMUtil_512.SIZE];
        KGCMUtil_512.copy(T[(int)(z[KGCMUtil_512.SIZE - 1] >>> 56) & 0xFF], r);
        for (int i = (KGCMUtil_512.SIZE << 3) - 2; i >= 0; --i)
        {
            KGCMUtil_512.multiplyX8(r, r);
            KGCMUtil_512.add(T[(int)(z[i >>> 3] >>> ((i & 7) << 3)) & 0xFF], r, r);
        }
        KGCMUtil_512.copy(r, z);
    }
}