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The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms.
This jar contains JCE provider for the Bouncy Castle Cryptography APIs for JDK 1.5 to JDK 1.7.
package org.spongycastle.crypto.params;
public class DESedeParameters
extends DESParameters
{
/*
* DES-EDE Key length in bytes.
*/
static public final int DES_EDE_KEY_LENGTH = 24;
public DESedeParameters(
byte[] key)
{
super(key);
if (isWeakKey(key, 0, key.length))
{
throw new IllegalArgumentException("attempt to create weak DESede key");
}
}
/**
* return true if the passed in key is a DES-EDE weak key.
*
* @param key bytes making up the key
* @param offset offset into the byte array the key starts at
* @param length number of bytes making up the key
*/
public static boolean isWeakKey(
byte[] key,
int offset,
int length)
{
for (int i = offset; i < length; i += DES_KEY_LENGTH)
{
if (DESParameters.isWeakKey(key, i))
{
return true;
}
}
return false;
}
/**
* return true if the passed in key is a DES-EDE weak key.
*
* @param key bytes making up the key
* @param offset offset into the byte array the key starts at
*/
public static boolean isWeakKey(
byte[] key,
int offset)
{
return isWeakKey(key, offset, key.length - offset);
}
}