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-rw-r--r--libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/engines/RC564Engine.java288
1 files changed, 0 insertions, 288 deletions
diff --git a/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/engines/RC564Engine.java b/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/engines/RC564Engine.java
deleted file mode 100644
index 06fcbf7c3..000000000
--- a/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/engines/RC564Engine.java
+++ /dev/null
@@ -1,288 +0,0 @@
-package org.spongycastle.crypto.engines;
-
-import org.spongycastle.crypto.BlockCipher;
-import org.spongycastle.crypto.CipherParameters;
-import org.spongycastle.crypto.params.RC5Parameters;
-
-/**
- * The specification for RC5 came from the <code>RC5 Encryption Algorithm</code>
- * publication in RSA CryptoBytes, Spring of 1995.
- * <em>http://www.rsasecurity.com/rsalabs/cryptobytes</em>.
- * <p>
- * This implementation is set to work with a 64 bit word size.
- * <p>
- * Implementation courtesy of Tito Pena.
- */
-public class RC564Engine
- implements BlockCipher
-{
- private static final int wordSize = 64;
- private static final int bytesPerWord = wordSize / 8;
-
- /*
- * the number of rounds to perform
- */
- private int _noRounds;
-
- /*
- * the expanded key array of size 2*(rounds + 1)
- */
- private long _S[];
-
- /*
- * our "magic constants" for wordSize 62
- *
- * Pw = Odd((e-2) * 2^wordsize)
- * Qw = Odd((o-2) * 2^wordsize)
- *
- * where e is the base of natural logarithms (2.718281828...)
- * and o is the golden ratio (1.61803398...)
- */
- private static final long P64 = 0xb7e151628aed2a6bL;
- private static final long Q64 = 0x9e3779b97f4a7c15L;
-
- private boolean forEncryption;
-
- /**
- * Create an instance of the RC5 encryption algorithm
- * and set some defaults
- */
- public RC564Engine()
- {
- _noRounds = 12;
- _S = null;
- }
-
- public String getAlgorithmName()
- {
- return "RC5-64";
- }
-
- public int getBlockSize()
- {
- return 2 * bytesPerWord;
- }
-
- /**
- * initialise a RC5-64 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 RC5Parameters))
- {
- throw new IllegalArgumentException("invalid parameter passed to RC564 init - " + params.getClass().getName());
- }
-
- RC5Parameters p = (RC5Parameters)params;
-
- this.forEncryption = forEncryption;
-
- _noRounds = p.getRounds();
-
- setKey(p.getKey());
- }
-
- public int processBlock(
- byte[] in,
- int inOff,
- byte[] out,
- int outOff)
- {
- return (forEncryption) ? encryptBlock(in, inOff, out, outOff)
- : decryptBlock(in, inOff, out, outOff);
- }
-
- public void reset()
- {
- }
-
- /**
- * Re-key the cipher.
- * <p>
- * @param key the key to be used
- */
- private void setKey(
- byte[] key)
- {
- //
- // KEY EXPANSION:
- //
- // There are 3 phases to the key expansion.
- //
- // Phase 1:
- // Copy the secret key K[0...b-1] into an array L[0..c-1] of
- // c = ceil(b/u), where u = wordSize/8 in little-endian order.
- // In other words, we fill up L using u consecutive key bytes
- // of K. Any unfilled byte positions in L are zeroed. In the
- // case that b = c = 0, set c = 1 and L[0] = 0.
- //
- long[] L = new long[(key.length + (bytesPerWord - 1)) / bytesPerWord];
-
- for (int i = 0; i != key.length; i++)
- {
- L[i / bytesPerWord] += (long)(key[i] & 0xff) << (8 * (i % bytesPerWord));
- }
-
- //
- // Phase 2:
- // Initialize S to a particular fixed pseudo-random bit pattern
- // using an arithmetic progression modulo 2^wordsize determined
- // by the magic numbers, Pw & Qw.
- //
- _S = new long[2*(_noRounds + 1)];
-
- _S[0] = P64;
- for (int i=1; i < _S.length; i++)
- {
- _S[i] = (_S[i-1] + Q64);
- }
-
- //
- // Phase 3:
- // Mix in the user's secret key in 3 passes over the arrays S & L.
- // The max of the arrays sizes is used as the loop control
- //
- int iter;
-
- if (L.length > _S.length)
- {
- iter = 3 * L.length;
- }
- else
- {
- iter = 3 * _S.length;
- }
-
- long A = 0, B = 0;
- int i = 0, j = 0;
-
- for (int k = 0; k < iter; k++)
- {
- A = _S[i] = rotateLeft(_S[i] + A + B, 3);
- B = L[j] = rotateLeft(L[j] + A + B, A+B);
- i = (i+1) % _S.length;
- j = (j+1) % L.length;
- }
- }
-
- /**
- * Encrypt the given block starting at the given offset and place
- * the result in the provided buffer starting at the given offset.
- * <p>
- * @param in in byte buffer containing data to encrypt
- * @param inOff offset into src buffer
- * @param out out buffer where encrypted data is written
- * @param outOff offset into out buffer
- */
- private int encryptBlock(
- byte[] in,
- int inOff,
- byte[] out,
- int outOff)
- {
- long A = bytesToWord(in, inOff) + _S[0];
- long B = bytesToWord(in, inOff + bytesPerWord) + _S[1];
-
- for (int i = 1; i <= _noRounds; i++)
- {
- A = rotateLeft(A ^ B, B) + _S[2*i];
- B = rotateLeft(B ^ A, A) + _S[2*i+1];
- }
-
- wordToBytes(A, out, outOff);
- wordToBytes(B, out, outOff + bytesPerWord);
-
- return 2 * bytesPerWord;
- }
-
- private int decryptBlock(
- byte[] in,
- int inOff,
- byte[] out,
- int outOff)
- {
- long A = bytesToWord(in, inOff);
- long B = bytesToWord(in, inOff + bytesPerWord);
-
- for (int i = _noRounds; i >= 1; i--)
- {
- B = rotateRight(B - _S[2*i+1], A) ^ A;
- A = rotateRight(A - _S[2*i], B) ^ B;
- }
-
- wordToBytes(A - _S[0], out, outOff);
- wordToBytes(B - _S[1], out, outOff + bytesPerWord);
-
- return 2 * bytesPerWord;
- }
-
-
- //////////////////////////////////////////////////////////////
- //
- // PRIVATE Helper Methods
- //
- //////////////////////////////////////////////////////////////
-
- /**
- * Perform a left "spin" of the word. The rotation of the given
- * word <em>x</em> is rotated left by <em>y</em> bits.
- * Only the <em>lg(wordSize)</em> low-order bits of <em>y</em>
- * are used to determine the rotation amount. Here it is
- * assumed that the wordsize used is a power of 2.
- * <p>
- * @param x word to rotate
- * @param y number of bits to rotate % wordSize
- */
- private long rotateLeft(long x, long y)
- {
- return ((x << (y & (wordSize-1))) | (x >>> (wordSize - (y & (wordSize-1)))));
- }
-
- /**
- * Perform a right "spin" of the word. The rotation of the given
- * word <em>x</em> is rotated left by <em>y</em> bits.
- * Only the <em>lg(wordSize)</em> low-order bits of <em>y</em>
- * are used to determine the rotation amount. Here it is
- * assumed that the wordsize used is a power of 2.
- * <p>
- * @param x word to rotate
- * @param y number of bits to rotate % wordSize
- */
- private long rotateRight(long x, long y)
- {
- return ((x >>> (y & (wordSize-1))) | (x << (wordSize - (y & (wordSize-1)))));
- }
-
- private long bytesToWord(
- byte[] src,
- int srcOff)
- {
- long word = 0;
-
- for (int i = bytesPerWord - 1; i >= 0; i--)
- {
- word = (word << 8) + (src[i + srcOff] & 0xff);
- }
-
- return word;
- }
-
- private void wordToBytes(
- long word,
- byte[] dst,
- int dstOff)
- {
- for (int i = 0; i < bytesPerWord; i++)
- {
- dst[i + dstOff] = (byte)word;
- word >>>= 8;
- }
- }
-}
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