/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package javax.crypto.spec;
import java.security.spec.AlgorithmParameterSpec;
import java.util.Arrays;
import org.apache.harmony.crypto.internal.nls.Messages;
/**
* The algorithm parameter specification for the <a
* href="http://www.ietf.org/rfc/rfc2040.txt">RC5</a> algorithm.
*
* @since Android 1.0
*/
public class RC5ParameterSpec implements AlgorithmParameterSpec {
private final int version;
private final int rounds;
private final int wordSize;
private final byte[] iv;
/**
* Creates a new <code>RC5ParameterSpec</code> instance with the specified
* version, round count an word size (in bits).
*
* @param version
* the version.
* @param rounds
* the round count.
* @param wordSize
* the word size (in bits).
*/
public RC5ParameterSpec(int version, int rounds, int wordSize) {
this.version = version;
this.rounds = rounds;
this.wordSize = wordSize;
this.iv = null;
}
/**
* Creates a new <code>RC5ParameterSpec</code> instance with the specified
* version, round count, word size (in bits) and an <i>initialization
* vector</i>.
* <p>
* The size of the <i>initialization vector</i> must be at least
* <code>2 * (wordSize / 8)</code> bytes which are copied to protect them
* against modification.
*
* @param version
* the version.
* @param rounds
* the round count.
* @param wordSize
* the word size (in bits).
* @param iv
* the initialization vector.
* @throws IllegalArgumentException
* if the initialization vector is null or shorter than <code>2
* * (wordSize / 8)</code>.
*/
public RC5ParameterSpec(int version, int rounds, int wordSize, byte[] iv) {
if (iv == null) {
throw new IllegalArgumentException(Messages.getString("crypto.31")); //$NON-NLS-1$
}
if (iv.length < 2 * (wordSize / 8)) {
throw new IllegalArgumentException(
Messages.getString("crypto.32")); //$NON-NLS-1$
}
this.version = version;
this.rounds = rounds;
this.wordSize = wordSize;
this.iv = new byte[2*(wordSize/8)];
System.arraycopy(iv, 0, this.iv, 0, 2*(wordSize/8));
}
/**
* Creates a new <code>RC5ParameterSpec</code> instance with the specified
* version, round count, wordSize (in bits), an <i>initialization vector</i>
* and an offset.
* <p>
* The size of the <i>initialization vector</i> must be at least
* <code>offset + (2 * (wordSize / 8))</code> bytes. The bytes starting at
* <code>offset</code> are copied to protect them against modification.
*
* @param version
* the version.
* @param rounds
* the round count.
* @param wordSize
* the word size (in bits).
* @param iv
* the initialization vector.
* @param offset
* the offset in the initialization vector.
* @throws IllegalArgumentException
* if the initialization vector is null of shorter than
* <code>offset + (2 * (wordSize / 8))</code>.
* @throws ArrayIndexOutOfBoundsException
* if <code>offset</code> is negative.
*/
public RC5ParameterSpec(int version, int rounds,
int wordSize, byte[] iv, int offset) {
if (iv == null) {
throw new IllegalArgumentException(Messages.getString("crypto.31")); //$NON-NLS-1$
}
if (offset < 0) {
throw new ArrayIndexOutOfBoundsException(Messages.getString("crypto.33")); //$NON-NLS-1$
}
if (iv.length - offset < 2 * (wordSize / 8)) {
throw new IllegalArgumentException(
Messages.getString("crypto.34")); //$NON-NLS-1$
}
this.version = version;
this.rounds = rounds;
this.wordSize = wordSize;
this.iv = new byte[offset+2*(wordSize/8)];
System.arraycopy(iv, offset, this.iv, 0, 2*(wordSize/8));
}
/**
* Returns the version.
*
* @return the version.
*/
public int getVersion() {
return version;
}
/**
* Returns the round count.
*
* @return the round count.
*/
public int getRounds() {
return rounds;
}
/**
* Returns the word size (in bits).
*
* @return the word size (in bits).
*/
public int getWordSize() {
return wordSize;
}
/**
* Returns a copy of the initialization vector.
*
* @return a copy of the initialization vector, or null if none specified.
*/
public byte[] getIV() {
if (iv == null) {
return null;
}
byte[] result = new byte[iv.length];
System.arraycopy(iv, 0, result, 0, iv.length);
return result;
}
/**
* Compares the specified object with this <code>RC5ParameterSpec</code>
* instance.
*
* @param obj
* the object to compare.
* @return true if version, round count, word size and initializaion vector
* of both objects are equal, otherwise false.
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof RC5ParameterSpec)) {
return false;
}
RC5ParameterSpec ps = (RC5ParameterSpec) obj;
return (version == ps.version)
&& (rounds == ps.rounds)
&& (wordSize == ps.wordSize)
&& (Arrays.equals(iv, ps.iv));
}
/**
* Returns the hash code of this <code>RC5ParameterSpec</code> instance.
*
* @return the hash code.
*/
@Override
public int hashCode() {
int result = version + rounds + wordSize;
if (iv == null) {
return result;
}
for (byte element : iv) {
result += element & 0xFF;
}
return result;
}
}
|
