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-rw-r--r--libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/engines/RC4Engine.java144
1 files changed, 0 insertions, 144 deletions
diff --git a/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/engines/RC4Engine.java b/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/engines/RC4Engine.java
deleted file mode 100644
index 712426f1e..000000000
--- a/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/engines/RC4Engine.java
+++ /dev/null
@@ -1,144 +0,0 @@
-package org.spongycastle.crypto.engines;
-
-import org.spongycastle.crypto.CipherParameters;
-import org.spongycastle.crypto.DataLengthException;
-import org.spongycastle.crypto.OutputLengthException;
-import org.spongycastle.crypto.StreamCipher;
-import org.spongycastle.crypto.params.KeyParameter;
-
-public class RC4Engine implements StreamCipher
-{
- private final static int STATE_LENGTH = 256;
-
- /*
- * variables to hold the state of the RC4 engine
- * during encryption and decryption
- */
-
- private byte[] engineState = null;
- private int x = 0;
- private int y = 0;
- private byte[] workingKey = null;
-
- /**
- * initialise a RC4 cipher.
- *
- * @param forEncryption whether or not we are for encryption.
- * @param params the parameters required to set up the cipher.
- * @exception IllegalArgumentException if the params argument is
- * inappropriate.
- */
- public void init(
- boolean forEncryption,
- CipherParameters params
- )
- {
- if (params instanceof KeyParameter)
- {
- /*
- * RC4 encryption and decryption is completely
- * symmetrical, so the 'forEncryption' is
- * irrelevant.
- */
- workingKey = ((KeyParameter)params).getKey();
- setKey(workingKey);
-
- return;
- }
-
- throw new IllegalArgumentException("invalid parameter passed to RC4 init - " + params.getClass().getName());
- }
-
- public String getAlgorithmName()
- {
- return "RC4";
- }
-
- public byte returnByte(byte in)
- {
- x = (x + 1) & 0xff;
- y = (engineState[x] + y) & 0xff;
-
- // swap
- byte tmp = engineState[x];
- engineState[x] = engineState[y];
- engineState[y] = tmp;
-
- // xor
- return (byte)(in ^ engineState[(engineState[x] + engineState[y]) & 0xff]);
- }
-
- public void processBytes(
- byte[] in,
- int inOff,
- int len,
- byte[] out,
- int outOff)
- {
- if ((inOff + len) > in.length)
- {
- throw new DataLengthException("input buffer too short");
- }
-
- if ((outOff + len) > out.length)
- {
- throw new OutputLengthException("output buffer too short");
- }
-
- for (int i = 0; i < len ; i++)
- {
- x = (x + 1) & 0xff;
- y = (engineState[x] + y) & 0xff;
-
- // swap
- byte tmp = engineState[x];
- engineState[x] = engineState[y];
- engineState[y] = tmp;
-
- // xor
- out[i+outOff] = (byte)(in[i + inOff]
- ^ engineState[(engineState[x] + engineState[y]) & 0xff]);
- }
- }
-
- public void reset()
- {
- setKey(workingKey);
- }
-
- // Private implementation
-
- private void setKey(byte[] keyBytes)
- {
- workingKey = keyBytes;
-
- // System.out.println("the key length is ; "+ workingKey.length);
-
- x = 0;
- y = 0;
-
- if (engineState == null)
- {
- engineState = new byte[STATE_LENGTH];
- }
-
- // reset the state of the engine
- for (int i=0; i < STATE_LENGTH; i++)
- {
- engineState[i] = (byte)i;
- }
-
- int i1 = 0;
- int i2 = 0;
-
- for (int i=0; i < STATE_LENGTH; i++)
- {
- i2 = ((keyBytes[i1] & 0xff) + engineState[i] + i2) & 0xff;
- // do the byte-swap inline
- byte tmp = engineState[i];
- engineState[i] = engineState[i2];
- engineState[i2] = tmp;
- i1 = (i1+1) % keyBytes.length;
- }
- }
-}