/*
 * Copyright (c) [2016] [ <ether.camp> ]
 * This file is part of the ethereumJ library.
 *
 * The ethereumJ library is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * The ethereumJ library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with the ethereumJ library. If not, see <http://www.gnu.org/licenses/>.
 */
// $Id: KeccakCore.java 258 2011-07-15 22:16:50Z tp $

package org.ethereum.crypto.cryptohash;

/**
 * This class implements the core operations for the Keccak digest
 * algorithm.
 *
 * <pre>
 * ==========================(LICENSE BEGIN)============================
 *
 * Copyright (c) 2007-2010  Projet RNRT SAPHIR
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * ===========================(LICENSE END)=============================
 * </pre>
 *
 * @version   $Revision: 258 $
 * @author    Thomas Pornin &lt;thomas.pornin@cryptolog.com&gt;
 */

abstract class KeccakCore extends DigestEngine{

	KeccakCore(String alg)
	{
		super(alg);
	}

	private long[] A;
	private byte[] tmpOut;

	private static final long[] RC = {
		0x0000000000000001L, 0x0000000000008082L,
		0x800000000000808AL, 0x8000000080008000L,
		0x000000000000808BL, 0x0000000080000001L,
		0x8000000080008081L, 0x8000000000008009L,
		0x000000000000008AL, 0x0000000000000088L,
		0x0000000080008009L, 0x000000008000000AL,
		0x000000008000808BL, 0x800000000000008BL,
		0x8000000000008089L, 0x8000000000008003L,
		0x8000000000008002L, 0x8000000000000080L,
		0x000000000000800AL, 0x800000008000000AL,
		0x8000000080008081L, 0x8000000000008080L,
		0x0000000080000001L, 0x8000000080008008L
	};

	/**
	 * Encode the 64-bit word {@code val} into the array
	 * {@code buf} at offset {@code off}, in little-endian
	 * convention (least significant byte first).
	 *
	 * @param val   the value to encode
	 * @param buf   the destination buffer
	 * @param off   the destination offset
	 */
	private static void encodeLELong(long val, byte[] buf, int off)
	{
		buf[off + 0] = (byte)val;
		buf[off + 1] = (byte)(val >>> 8);
		buf[off + 2] = (byte)(val >>> 16);
		buf[off + 3] = (byte)(val >>> 24);
		buf[off + 4] = (byte)(val >>> 32);
		buf[off + 5] = (byte)(val >>> 40);
		buf[off + 6] = (byte)(val >>> 48);
		buf[off + 7] = (byte)(val >>> 56);
	}

	/**
	 * Decode a 64-bit little-endian word from the array {@code buf}
	 * at offset {@code off}.
	 *
	 * @param buf   the source buffer
	 * @param off   the source offset
	 * @return  the decoded value
	 */
	private static long decodeLELong(byte[] buf, int off)
	{
		return (buf[off + 0] & 0xFFL)
			| ((buf[off + 1] & 0xFFL) << 8)
			| ((buf[off + 2] & 0xFFL) << 16)
			| ((buf[off + 3] & 0xFFL) << 24)
			| ((buf[off + 4] & 0xFFL) << 32)
			| ((buf[off + 5] & 0xFFL) << 40)
			| ((buf[off + 6] & 0xFFL) << 48)
			| ((buf[off + 7] & 0xFFL) << 56);
	}

	/** @see org.ethereum.crypto.cryptohash.DigestEngine */
	protected void engineReset()
	{
		doReset();
	}

	/** @see org.ethereum.crypto.cryptohash.DigestEngine */
	protected void processBlock(byte[] data)
	{
		/* Input block */
		for (int i = 0; i < data.length; i += 8)
			A[i >>> 3] ^= decodeLELong(data, i);

		long t0, t1, t2, t3, t4;
		long tt0, tt1, tt2, tt3, tt4;
		long t, kt;
		long c0, c1, c2, c3, c4, bnn;

		/*
		 * Unrolling four rounds kills performance big time
		 * on Intel x86 Core2, in both 32-bit and 64-bit modes
		 * (less than 1 MB/s instead of 55 MB/s on x86-64).
		 * Unrolling two rounds appears to be fine.
		 */
		for (int j = 0; j < 24; j += 2) {

			tt0 = A[ 1] ^ A[ 6];
			tt1 = A[11] ^ A[16];
			tt0 ^= A[21] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[ 4] ^ A[ 9];
			tt3 = A[14] ^ A[19];
			tt0 ^= A[24];
			tt2 ^= tt3;
			t0 = tt0 ^ tt2;

			tt0 = A[ 2] ^ A[ 7];
			tt1 = A[12] ^ A[17];
			tt0 ^= A[22] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[ 0] ^ A[ 5];
			tt3 = A[10] ^ A[15];
			tt0 ^= A[20];
			tt2 ^= tt3;
			t1 = tt0 ^ tt2;

			tt0 = A[ 3] ^ A[ 8];
			tt1 = A[13] ^ A[18];
			tt0 ^= A[23] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[ 1] ^ A[ 6];
			tt3 = A[11] ^ A[16];
			tt0 ^= A[21];
			tt2 ^= tt3;
			t2 = tt0 ^ tt2;

			tt0 = A[ 4] ^ A[ 9];
			tt1 = A[14] ^ A[19];
			tt0 ^= A[24] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[ 2] ^ A[ 7];
			tt3 = A[12] ^ A[17];
			tt0 ^= A[22];
			tt2 ^= tt3;
			t3 = tt0 ^ tt2;

			tt0 = A[ 0] ^ A[ 5];
			tt1 = A[10] ^ A[15];
			tt0 ^= A[20] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[ 3] ^ A[ 8];
			tt3 = A[13] ^ A[18];
			tt0 ^= A[23];
			tt2 ^= tt3;
			t4 = tt0 ^ tt2;

			A[ 0] = A[ 0] ^ t0;
			A[ 5] = A[ 5] ^ t0;
			A[10] = A[10] ^ t0;
			A[15] = A[15] ^ t0;
			A[20] = A[20] ^ t0;
			A[ 1] = A[ 1] ^ t1;
			A[ 6] = A[ 6] ^ t1;
			A[11] = A[11] ^ t1;
			A[16] = A[16] ^ t1;
			A[21] = A[21] ^ t1;
			A[ 2] = A[ 2] ^ t2;
			A[ 7] = A[ 7] ^ t2;
			A[12] = A[12] ^ t2;
			A[17] = A[17] ^ t2;
			A[22] = A[22] ^ t2;
			A[ 3] = A[ 3] ^ t3;
			A[ 8] = A[ 8] ^ t3;
			A[13] = A[13] ^ t3;
			A[18] = A[18] ^ t3;
			A[23] = A[23] ^ t3;
			A[ 4] = A[ 4] ^ t4;
			A[ 9] = A[ 9] ^ t4;
			A[14] = A[14] ^ t4;
			A[19] = A[19] ^ t4;
			A[24] = A[24] ^ t4;
			A[ 5] = (A[ 5] << 36) | (A[ 5] >>> (64 - 36));
			A[10] = (A[10] << 3) | (A[10] >>> (64 - 3));
			A[15] = (A[15] << 41) | (A[15] >>> (64 - 41));
			A[20] = (A[20] << 18) | (A[20] >>> (64 - 18));
			A[ 1] = (A[ 1] << 1) | (A[ 1] >>> (64 - 1));
			A[ 6] = (A[ 6] << 44) | (A[ 6] >>> (64 - 44));
			A[11] = (A[11] << 10) | (A[11] >>> (64 - 10));
			A[16] = (A[16] << 45) | (A[16] >>> (64 - 45));
			A[21] = (A[21] << 2) | (A[21] >>> (64 - 2));
			A[ 2] = (A[ 2] << 62) | (A[ 2] >>> (64 - 62));
			A[ 7] = (A[ 7] << 6) | (A[ 7] >>> (64 - 6));
			A[12] = (A[12] << 43) | (A[12] >>> (64 - 43));
			A[17] = (A[17] << 15) | (A[17] >>> (64 - 15));
			A[22] = (A[22] << 61) | (A[22] >>> (64 - 61));
			A[ 3] = (A[ 3] << 28) | (A[ 3] >>> (64 - 28));
			A[ 8] = (A[ 8] << 55) | (A[ 8] >>> (64 - 55));
			A[13] = (A[13] << 25) | (A[13] >>> (64 - 25));
			A[18] = (A[18] << 21) | (A[18] >>> (64 - 21));
			A[23] = (A[23] << 56) | (A[23] >>> (64 - 56));
			A[ 4] = (A[ 4] << 27) | (A[ 4] >>> (64 - 27));
			A[ 9] = (A[ 9] << 20) | (A[ 9] >>> (64 - 20));
			A[14] = (A[14] << 39) | (A[14] >>> (64 - 39));
			A[19] = (A[19] << 8) | (A[19] >>> (64 - 8));
			A[24] = (A[24] << 14) | (A[24] >>> (64 - 14));
			bnn = ~A[12];
			kt = A[ 6] | A[12];
			c0 = A[ 0] ^ kt;
			kt = bnn | A[18];
			c1 = A[ 6] ^ kt;
			kt = A[18] & A[24];
			c2 = A[12] ^ kt;
			kt = A[24] | A[ 0];
			c3 = A[18] ^ kt;
			kt = A[ 0] & A[ 6];
			c4 = A[24] ^ kt;
			A[ 0] = c0;
			A[ 6] = c1;
			A[12] = c2;
			A[18] = c3;
			A[24] = c4;
			bnn = ~A[22];
			kt = A[ 9] | A[10];
			c0 = A[ 3] ^ kt;
			kt = A[10] & A[16];
			c1 = A[ 9] ^ kt;
			kt = A[16] | bnn;
			c2 = A[10] ^ kt;
			kt = A[22] | A[ 3];
			c3 = A[16] ^ kt;
			kt = A[ 3] & A[ 9];
			c4 = A[22] ^ kt;
			A[ 3] = c0;
			A[ 9] = c1;
			A[10] = c2;
			A[16] = c3;
			A[22] = c4;
			bnn = ~A[19];
			kt = A[ 7] | A[13];
			c0 = A[ 1] ^ kt;
			kt = A[13] & A[19];
			c1 = A[ 7] ^ kt;
			kt = bnn & A[20];
			c2 = A[13] ^ kt;
			kt = A[20] | A[ 1];
			c3 = bnn ^ kt;
			kt = A[ 1] & A[ 7];
			c4 = A[20] ^ kt;
			A[ 1] = c0;
			A[ 7] = c1;
			A[13] = c2;
			A[19] = c3;
			A[20] = c4;
			bnn = ~A[17];
			kt = A[ 5] & A[11];
			c0 = A[ 4] ^ kt;
			kt = A[11] | A[17];
			c1 = A[ 5] ^ kt;
			kt = bnn | A[23];
			c2 = A[11] ^ kt;
			kt = A[23] & A[ 4];
			c3 = bnn ^ kt;
			kt = A[ 4] | A[ 5];
			c4 = A[23] ^ kt;
			A[ 4] = c0;
			A[ 5] = c1;
			A[11] = c2;
			A[17] = c3;
			A[23] = c4;
			bnn = ~A[ 8];
			kt = bnn & A[14];
			c0 = A[ 2] ^ kt;
			kt = A[14] | A[15];
			c1 = bnn ^ kt;
			kt = A[15] & A[21];
			c2 = A[14] ^ kt;
			kt = A[21] | A[ 2];
			c3 = A[15] ^ kt;
			kt = A[ 2] & A[ 8];
			c4 = A[21] ^ kt;
			A[ 2] = c0;
			A[ 8] = c1;
			A[14] = c2;
			A[15] = c3;
			A[21] = c4;
			A[ 0] = A[ 0] ^ RC[j + 0];

			tt0 = A[ 6] ^ A[ 9];
			tt1 = A[ 7] ^ A[ 5];
			tt0 ^= A[ 8] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[24] ^ A[22];
			tt3 = A[20] ^ A[23];
			tt0 ^= A[21];
			tt2 ^= tt3;
			t0 = tt0 ^ tt2;

			tt0 = A[12] ^ A[10];
			tt1 = A[13] ^ A[11];
			tt0 ^= A[14] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[ 0] ^ A[ 3];
			tt3 = A[ 1] ^ A[ 4];
			tt0 ^= A[ 2];
			tt2 ^= tt3;
			t1 = tt0 ^ tt2;

			tt0 = A[18] ^ A[16];
			tt1 = A[19] ^ A[17];
			tt0 ^= A[15] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[ 6] ^ A[ 9];
			tt3 = A[ 7] ^ A[ 5];
			tt0 ^= A[ 8];
			tt2 ^= tt3;
			t2 = tt0 ^ tt2;

			tt0 = A[24] ^ A[22];
			tt1 = A[20] ^ A[23];
			tt0 ^= A[21] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[12] ^ A[10];
			tt3 = A[13] ^ A[11];
			tt0 ^= A[14];
			tt2 ^= tt3;
			t3 = tt0 ^ tt2;

			tt0 = A[ 0] ^ A[ 3];
			tt1 = A[ 1] ^ A[ 4];
			tt0 ^= A[ 2] ^ tt1;
			tt0 = (tt0 << 1) | (tt0 >>> 63);
			tt2 = A[18] ^ A[16];
			tt3 = A[19] ^ A[17];
			tt0 ^= A[15];
			tt2 ^= tt3;
			t4 = tt0 ^ tt2;

			A[ 0] = A[ 0] ^ t0;
			A[ 3] = A[ 3] ^ t0;
			A[ 1] = A[ 1] ^ t0;
			A[ 4] = A[ 4] ^ t0;
			A[ 2] = A[ 2] ^ t0;
			A[ 6] = A[ 6] ^ t1;
			A[ 9] = A[ 9] ^ t1;
			A[ 7] = A[ 7] ^ t1;
			A[ 5] = A[ 5] ^ t1;
			A[ 8] = A[ 8] ^ t1;
			A[12] = A[12] ^ t2;
			A[10] = A[10] ^ t2;
			A[13] = A[13] ^ t2;
			A[11] = A[11] ^ t2;
			A[14] = A[14] ^ t2;
			A[18] = A[18] ^ t3;
			A[16] = A[16] ^ t3;
			A[19] = A[19] ^ t3;
			A[17] = A[17] ^ t3;
			A[15] = A[15] ^ t3;
			A[24] = A[24] ^ t4;
			A[22] = A[22] ^ t4;
			A[20] = A[20] ^ t4;
			A[23] = A[23] ^ t4;
			A[21] = A[21] ^ t4;
			A[ 3] = (A[ 3] << 36) | (A[ 3] >>> (64 - 36));
			A[ 1] = (A[ 1] << 3) | (A[ 1] >>> (64 - 3));
			A[ 4] = (A[ 4] << 41) | (A[ 4] >>> (64 - 41));
			A[ 2] = (A[ 2] << 18) | (A[ 2] >>> (64 - 18));
			A[ 6] = (A[ 6] << 1) | (A[ 6] >>> (64 - 1));
			A[ 9] = (A[ 9] << 44) | (A[ 9] >>> (64 - 44));
			A[ 7] = (A[ 7] << 10) | (A[ 7] >>> (64 - 10));
			A[ 5] = (A[ 5] << 45) | (A[ 5] >>> (64 - 45));
			A[ 8] = (A[ 8] << 2) | (A[ 8] >>> (64 - 2));
			A[12] = (A[12] << 62) | (A[12] >>> (64 - 62));
			A[10] = (A[10] << 6) | (A[10] >>> (64 - 6));
			A[13] = (A[13] << 43) | (A[13] >>> (64 - 43));
			A[11] = (A[11] << 15) | (A[11] >>> (64 - 15));
			A[14] = (A[14] << 61) | (A[14] >>> (64 - 61));
			A[18] = (A[18] << 28) | (A[18] >>> (64 - 28));
			A[16] = (A[16] << 55) | (A[16] >>> (64 - 55));
			A[19] = (A[19] << 25) | (A[19] >>> (64 - 25));
			A[17] = (A[17] << 21) | (A[17] >>> (64 - 21));
			A[15] = (A[15] << 56) | (A[15] >>> (64 - 56));
			A[24] = (A[24] << 27) | (A[24] >>> (64 - 27));
			A[22] = (A[22] << 20) | (A[22] >>> (64 - 20));
			A[20] = (A[20] << 39) | (A[20] >>> (64 - 39));
			A[23] = (A[23] << 8) | (A[23] >>> (64 - 8));
			A[21] = (A[21] << 14) | (A[21] >>> (64 - 14));
			bnn = ~A[13];
			kt = A[ 9] | A[13];
			c0 = A[ 0] ^ kt;
			kt = bnn | A[17];
			c1 = A[ 9] ^ kt;
			kt = A[17] & A[21];
			c2 = A[13] ^ kt;
			kt = A[21] | A[ 0];
			c3 = A[17] ^ kt;
			kt = A[ 0] & A[ 9];
			c4 = A[21] ^ kt;
			A[ 0] = c0;
			A[ 9] = c1;
			A[13] = c2;
			A[17] = c3;
			A[21] = c4;
			bnn = ~A[14];
			kt = A[22] | A[ 1];
			c0 = A[18] ^ kt;
			kt = A[ 1] & A[ 5];
			c1 = A[22] ^ kt;
			kt = A[ 5] | bnn;
			c2 = A[ 1] ^ kt;
			kt = A[14] | A[18];
			c3 = A[ 5] ^ kt;
			kt = A[18] & A[22];
			c4 = A[14] ^ kt;
			A[18] = c0;
			A[22] = c1;
			A[ 1] = c2;
			A[ 5] = c3;
			A[14] = c4;
			bnn = ~A[23];
			kt = A[10] | A[19];
			c0 = A[ 6] ^ kt;
			kt = A[19] & A[23];
			c1 = A[10] ^ kt;
			kt = bnn & A[ 2];
			c2 = A[19] ^ kt;
			kt = A[ 2] | A[ 6];
			c3 = bnn ^ kt;
			kt = A[ 6] & A[10];
			c4 = A[ 2] ^ kt;
			A[ 6] = c0;
			A[10] = c1;
			A[19] = c2;
			A[23] = c3;
			A[ 2] = c4;
			bnn = ~A[11];
			kt = A[ 3] & A[ 7];
			c0 = A[24] ^ kt;
			kt = A[ 7] | A[11];
			c1 = A[ 3] ^ kt;
			kt = bnn | A[15];
			c2 = A[ 7] ^ kt;
			kt = A[15] & A[24];
			c3 = bnn ^ kt;
			kt = A[24] | A[ 3];
			c4 = A[15] ^ kt;
			A[24] = c0;
			A[ 3] = c1;
			A[ 7] = c2;
			A[11] = c3;
			A[15] = c4;
			bnn = ~A[16];
			kt = bnn & A[20];
			c0 = A[12] ^ kt;
			kt = A[20] | A[ 4];
			c1 = bnn ^ kt;
			kt = A[ 4] & A[ 8];
			c2 = A[20] ^ kt;
			kt = A[ 8] | A[12];
			c3 = A[ 4] ^ kt;
			kt = A[12] & A[16];
			c4 = A[ 8] ^ kt;
			A[12] = c0;
			A[16] = c1;
			A[20] = c2;
			A[ 4] = c3;
			A[ 8] = c4;
			A[ 0] = A[ 0] ^ RC[j + 1];
			t = A[ 5];
			A[ 5] = A[18];
			A[18] = A[11];
			A[11] = A[10];
			A[10] = A[ 6];
			A[ 6] = A[22];
			A[22] = A[20];
			A[20] = A[12];
			A[12] = A[19];
			A[19] = A[15];
			A[15] = A[24];
			A[24] = A[ 8];
			A[ 8] = t;
			t = A[ 1];
			A[ 1] = A[ 9];
			A[ 9] = A[14];
			A[14] = A[ 2];
			A[ 2] = A[13];
			A[13] = A[23];
			A[23] = A[ 4];
			A[ 4] = A[21];
			A[21] = A[16];
			A[16] = A[ 3];
			A[ 3] = A[17];
			A[17] = A[ 7];
			A[ 7] = t;
		}
	}

	/** @see org.ethereum.crypto.cryptohash.DigestEngine */
	protected void doPadding(byte[] out, int off)
	{
		int ptr = flush();
		byte[] buf = getBlockBuffer();
		if ((ptr + 1) == buf.length) {
			buf[ptr] = (byte)0x81;
		} else {
			buf[ptr] = (byte)0x01;
			for (int i = ptr + 1; i < (buf.length - 1); i ++)
				buf[i] = 0;
			buf[buf.length - 1] = (byte)0x80;
		}
		processBlock(buf);
		A[ 1] = ~A[ 1];
		A[ 2] = ~A[ 2];
		A[ 8] = ~A[ 8];
		A[12] = ~A[12];
		A[17] = ~A[17];
		A[20] = ~A[20];
		int dlen = engineGetDigestLength();
		for (int i = 0; i < dlen; i += 8)
			encodeLELong(A[i >>> 3], tmpOut, i);
		System.arraycopy(tmpOut, 0, out, off, dlen);
	}

	/** @see org.ethereum.crypto.cryptohash.DigestEngine */
	protected void doInit()
	{
		A = new long[25];
		tmpOut = new byte[(engineGetDigestLength() + 7) & ~7];
		doReset();
	}

	/** @see org.ethereum.crypto.cryptohash.Digest */
	public int getBlockLength()
	{
		return 200 - 2 * engineGetDigestLength();
	}

	private final void doReset()
	{
		for (int i = 0; i < 25; i ++)
			A[i] = 0;
		A[ 1] = 0xFFFFFFFFFFFFFFFFL;
		A[ 2] = 0xFFFFFFFFFFFFFFFFL;
		A[ 8] = 0xFFFFFFFFFFFFFFFFL;
		A[12] = 0xFFFFFFFFFFFFFFFFL;
		A[17] = 0xFFFFFFFFFFFFFFFFL;
		A[20] = 0xFFFFFFFFFFFFFFFFL;
	}

	/** @see org.ethereum.crypto.cryptohash.DigestEngine */
	protected Digest copyState(KeccakCore dst)
	{
		System.arraycopy(A, 0, dst.A, 0, 25);
		return super.copyState(dst);
	}

	/** @see org.ethereum.crypto.cryptohash.Digest */
	public String toString()
	{
		return "Keccak-" + (engineGetDigestLength() << 3);
	}
}
