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	/*
	* Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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 General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package com.sun.crypto.provider;

	import java.util.Arrays;
	import java.nio.ByteBuffer;

	import javax.crypto.MacSpi;
	import javax.crypto.SecretKey;
	import javax.crypto.spec.SecretKeySpec;
	import javax.crypto.spec.PBEKeySpec;
	import javax.crypto.spec.PBEParameterSpec;
	import java.security.*;
	import java.security.spec.*;

	/**
	* This is an implementation of the PBMAC1 algorithms as defined
	* in PKCS#5 v2.1 standard.
	*/
	abstract class PBMAC1Core extends HmacCore {

	// NOTE: this class inherits the Cloneable interface from HmacCore
	// Need to override clone() if mutable fields are added.
	private final String kdfAlgo;
	private final String hashAlgo;
	private final int blockLength; // in octets

	/**
	* Creates an instance of PBMAC1 according to the selected
	* password-based key derivation function.
	*/
	PBMAC1Core(String kdfAlgo, String hashAlgo, int blockLength)
	throws NoSuchAlgorithmException {
	super(hashAlgo, blockLength);
	this.kdfAlgo = kdfAlgo;
	this.hashAlgo = hashAlgo;
	this.blockLength = blockLength;
	}

	private static PBKDF2Core getKDFImpl(String algo) {
	PBKDF2Core kdf = null;
	switch(algo) {
	case "HmacSHA1":
	kdf = new PBKDF2Core.HmacSHA1();
	break;
	case "HmacSHA224":
	kdf = new PBKDF2Core.HmacSHA224();
	break;
	case "HmacSHA256":
	kdf = new PBKDF2Core.HmacSHA256();
	break;
	case "HmacSHA384":
	kdf = new PBKDF2Core.HmacSHA384();
	break;
	case "HmacSHA512":
	kdf = new PBKDF2Core.HmacSHA512();
	break;
	default:
	throw new ProviderException(
	"No MAC implementation for " + algo);
	}
	return kdf;
	}

	/**
	* Initializes the HMAC with the given secret key and algorithm parameters.
	*
	* @param key the secret key.
	* @param params the algorithm parameters.
	*
	* @exception InvalidKeyException if the given key is inappropriate for
	* initializing this MAC.
	* @exception InvalidAlgorithmParameterException if the given algorithm
	* parameters are inappropriate for this MAC.
	*/
	protected void engineInit(Key key, AlgorithmParameterSpec params)
	throws InvalidKeyException, InvalidAlgorithmParameterException {
	char[] passwdChars;
	byte[] salt = null;
	int iCount = 0;
	if (key instanceof javax.crypto.interfaces.PBEKey) {
	javax.crypto.interfaces.PBEKey pbeKey =
	(javax.crypto.interfaces.PBEKey) key;
	passwdChars = pbeKey.getPassword();
	salt = pbeKey.getSalt(); // maybe null if unspecified
	iCount = pbeKey.getIterationCount(); // maybe 0 if unspecified
	} else if (key instanceof SecretKey) {
	byte[] passwdBytes;
	if (!(key.getAlgorithm().regionMatches(true, 0, "PBE", 0, 3)) \|\|
	(passwdBytes = key.getEncoded()) == null) {
	throw new InvalidKeyException("Missing password");
	}
	passwdChars = new char[passwdBytes.length];
	for (int i=0; i<passwdChars.length; i++) {
	passwdChars[i] = (char) (passwdBytes[i] & 0x7f);
	}
	Arrays.fill(passwdBytes, (byte)0x00);
	} else {
	throw new InvalidKeyException("SecretKey of PBE type required");
	}

	PBEKeySpec pbeSpec;
	try {
	if (params == null) {
	// should not auto-generate default values since current
	// javax.crypto.Mac api does not have any method for caller to
	// retrieve the generated defaults.
	if ((salt == null) \|\| (iCount == 0)) {
	throw new InvalidAlgorithmParameterException
	("PBEParameterSpec required for salt and iteration count");
	}
	} else if (!(params instanceof PBEParameterSpec)) {
	throw new InvalidAlgorithmParameterException
	("PBEParameterSpec type required");
	} else {
	PBEParameterSpec pbeParams = (PBEParameterSpec) params;
	// make sure the parameter values are consistent
	if (salt != null) {
	if (!Arrays.equals(salt, pbeParams.getSalt())) {
	throw new InvalidAlgorithmParameterException
	("Inconsistent value of salt between key and params");
	}
	} else {
	salt = pbeParams.getSalt();
	}
	if (iCount != 0) {
	if (iCount != pbeParams.getIterationCount()) {
	throw new InvalidAlgorithmParameterException
	("Different iteration count between key and params");
	}
	} else {
	iCount = pbeParams.getIterationCount();
	}
	}
	// For security purpose, we need to enforce a minimum length
	// for salt; just require the minimum salt length to be 8-byte
	// which is what PKCS#5 recommends and openssl does.
	if (salt.length < 8) {
	throw new InvalidAlgorithmParameterException
	("Salt must be at least 8 bytes long");
	}
	if (iCount <= 0) {
	throw new InvalidAlgorithmParameterException
	("IterationCount must be a positive number");
	}

	pbeSpec = new PBEKeySpec(passwdChars, salt, iCount, blockLength);
	// password char[] was cloned in PBEKeySpec constructor,
	// so we can zero it out here
	} finally {
	Arrays.fill(passwdChars, '\0');
	}

	SecretKey s;
	PBKDF2Core kdf = getKDFImpl(kdfAlgo);
	try {
	s = kdf.engineGenerateSecret(pbeSpec);
	} catch (InvalidKeySpecException ikse) {
	InvalidKeyException ike =
	new InvalidKeyException("Cannot construct PBE key");
	ike.initCause(ikse);
	throw ike;
	}
	byte[] derivedKey = s.getEncoded();
	SecretKey cipherKey = new SecretKeySpec(derivedKey, kdfAlgo);

	super.engineInit(cipherKey, null);
	}

	public static final class HmacSHA1 extends PBMAC1Core {
	public HmacSHA1() throws NoSuchAlgorithmException {
	super("HmacSHA1", "SHA1", 64);
	}
	}

	public static final class HmacSHA224 extends PBMAC1Core {
	public HmacSHA224() throws NoSuchAlgorithmException {
	super("HmacSHA224", "SHA-224", 64);
	}
	}

	public static final class HmacSHA256 extends PBMAC1Core {
	public HmacSHA256() throws NoSuchAlgorithmException {
	super("HmacSHA256", "SHA-256", 64);
	}
	}

	public static final class HmacSHA384 extends PBMAC1Core {
	public HmacSHA384() throws NoSuchAlgorithmException {
	super("HmacSHA384", "SHA-384", 128);
	}
	}

	public static final class HmacSHA512 extends PBMAC1Core {
	public HmacSHA512() throws NoSuchAlgorithmException {
	super("HmacSHA512", "SHA-512", 128);
	}
	}
	}

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