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-rw-r--r--bcprov/src/main/java/org/bouncycastle/crypto/engines/IDEAEngine.java357
1 files changed, 0 insertions, 357 deletions
diff --git a/bcprov/src/main/java/org/bouncycastle/crypto/engines/IDEAEngine.java b/bcprov/src/main/java/org/bouncycastle/crypto/engines/IDEAEngine.java
deleted file mode 100644
index 08cf738..0000000
--- a/bcprov/src/main/java/org/bouncycastle/crypto/engines/IDEAEngine.java
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@@ -1,357 +0,0 @@
-package org.bouncycastle.crypto.engines;
-
-import org.bouncycastle.crypto.BlockCipher;
-import org.bouncycastle.crypto.CipherParameters;
-import org.bouncycastle.crypto.DataLengthException;
-import org.bouncycastle.crypto.OutputLengthException;
-import org.bouncycastle.crypto.params.KeyParameter;
-
-/**
- * A class that provides a basic International Data Encryption Algorithm (IDEA) engine.
- * <p>
- * This implementation is based on the "HOWTO: INTERNATIONAL DATA ENCRYPTION ALGORITHM"
- * implementation summary by Fauzan Mirza (F.U.Mirza@sheffield.ac.uk). (barring 1 typo at the
- * end of the mulinv function!).
- * <p>
- * It can be found at ftp://ftp.funet.fi/pub/crypt/cryptography/symmetric/idea/
- * <p>
- * Note: This algorithm was patented in the USA, Japan and Europe. These patents expired in 2011/2012.
- */
-public class IDEAEngine
- implements BlockCipher
-{
- protected static final int BLOCK_SIZE = 8;
-
- private int[] workingKey = null;
-
- /**
- * standard constructor.
- */
- public IDEAEngine()
- {
- }
-
- /**
- * initialise an IDEA 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)
- {
- workingKey = generateWorkingKey(forEncryption,
- ((KeyParameter)params).getKey());
- return;
- }
-
- throw new IllegalArgumentException("invalid parameter passed to IDEA init - " + params.getClass().getName());
- }
-
- public String getAlgorithmName()
- {
- return "IDEA";
- }
-
- public int getBlockSize()
- {
- return BLOCK_SIZE;
- }
-
- public int processBlock(
- byte[] in,
- int inOff,
- byte[] out,
- int outOff)
- {
- if (workingKey == null)
- {
- throw new IllegalStateException("IDEA engine not initialised");
- }
-
- if ((inOff + BLOCK_SIZE) > in.length)
- {
- throw new DataLengthException("input buffer too short");
- }
-
- if ((outOff + BLOCK_SIZE) > out.length)
- {
- throw new OutputLengthException("output buffer too short");
- }
-
- ideaFunc(workingKey, in, inOff, out, outOff);
-
- return BLOCK_SIZE;
- }
-
- public void reset()
- {
- }
-
- private static final int MASK = 0xffff;
- private static final int BASE = 0x10001;
-
- private int bytesToWord(
- byte[] in,
- int inOff)
- {
- return ((in[inOff] << 8) & 0xff00) + (in[inOff + 1] & 0xff);
- }
-
- private void wordToBytes(
- int word,
- byte[] out,
- int outOff)
- {
- out[outOff] = (byte)(word >>> 8);
- out[outOff + 1] = (byte)word;
- }
-
- /**
- * return x = x * y where the multiplication is done modulo
- * 65537 (0x10001) (as defined in the IDEA specification) and
- * a zero input is taken to be 65536 (0x10000).
- *
- * @param x the x value
- * @param y the y value
- * @return x = x * y
- */
- private int mul(
- int x,
- int y)
- {
- if (x == 0)
- {
- x = (BASE - y);
- }
- else if (y == 0)
- {
- x = (BASE - x);
- }
- else
- {
- int p = x * y;
-
- y = p & MASK;
- x = p >>> 16;
- x = y - x + ((y < x) ? 1 : 0);
- }
-
- return x & MASK;
- }
-
- private void ideaFunc(
- int[] workingKey,
- byte[] in,
- int inOff,
- byte[] out,
- int outOff)
- {
- int x0, x1, x2, x3, t0, t1;
- int keyOff = 0;
-
- x0 = bytesToWord(in, inOff);
- x1 = bytesToWord(in, inOff + 2);
- x2 = bytesToWord(in, inOff + 4);
- x3 = bytesToWord(in, inOff + 6);
-
- for (int round = 0; round < 8; round++)
- {
- x0 = mul(x0, workingKey[keyOff++]);
- x1 += workingKey[keyOff++];
- x1 &= MASK;
- x2 += workingKey[keyOff++];
- x2 &= MASK;
- x3 = mul(x3, workingKey[keyOff++]);
-
- t0 = x1;
- t1 = x2;
- x2 ^= x0;
- x1 ^= x3;
-
- x2 = mul(x2, workingKey[keyOff++]);
- x1 += x2;
- x1 &= MASK;
-
- x1 = mul(x1, workingKey[keyOff++]);
- x2 += x1;
- x2 &= MASK;
-
- x0 ^= x1;
- x3 ^= x2;
- x1 ^= t1;
- x2 ^= t0;
- }
-
- wordToBytes(mul(x0, workingKey[keyOff++]), out, outOff);
- wordToBytes(x2 + workingKey[keyOff++], out, outOff + 2); /* NB: Order */
- wordToBytes(x1 + workingKey[keyOff++], out, outOff + 4);
- wordToBytes(mul(x3, workingKey[keyOff]), out, outOff + 6);
- }
-
- /**
- * The following function is used to expand the user key to the encryption
- * subkey. The first 16 bytes are the user key, and the rest of the subkey
- * is calculated by rotating the previous 16 bytes by 25 bits to the left,
- * and so on until the subkey is completed.
- */
- private int[] expandKey(
- byte[] uKey)
- {
- int[] key = new int[52];
-
- if (uKey.length < 16)
- {
- byte[] tmp = new byte[16];
-
- System.arraycopy(uKey, 0, tmp, tmp.length - uKey.length, uKey.length);
-
- uKey = tmp;
- }
-
- for (int i = 0; i < 8; i++)
- {
- key[i] = bytesToWord(uKey, i * 2);
- }
-
- for (int i = 8; i < 52; i++)
- {
- if ((i & 7) < 6)
- {
- key[i] = ((key[i - 7] & 127) << 9 | key[i - 6] >> 7) & MASK;
- }
- else if ((i & 7) == 6)
- {
- key[i] = ((key[i - 7] & 127) << 9 | key[i - 14] >> 7) & MASK;
- }
- else
- {
- key[i] = ((key[i - 15] & 127) << 9 | key[i - 14] >> 7) & MASK;
- }
- }
-
- return key;
- }
-
- /**
- * This function computes multiplicative inverse using Euclid's Greatest
- * Common Divisor algorithm. Zero and one are self inverse.
- * <p>
- * i.e. x * mulInv(x) == 1 (modulo BASE)
- */
- private int mulInv(
- int x)
- {
- int t0, t1, q, y;
-
- if (x < 2)
- {
- return x;
- }
-
- t0 = 1;
- t1 = BASE / x;
- y = BASE % x;
-
- while (y != 1)
- {
- q = x / y;
- x = x % y;
- t0 = (t0 + (t1 * q)) & MASK;
- if (x == 1)
- {
- return t0;
- }
- q = y / x;
- y = y % x;
- t1 = (t1 + (t0 * q)) & MASK;
- }
-
- return (1 - t1) & MASK;
- }
-
- /**
- * Return the additive inverse of x.
- * <p>
- * i.e. x + addInv(x) == 0
- */
- int addInv(
- int x)
- {
- return (0 - x) & MASK;
- }
-
- /**
- * The function to invert the encryption subkey to the decryption subkey.
- * It also involves the multiplicative inverse and the additive inverse functions.
- */
- private int[] invertKey(
- int[] inKey)
- {
- int t1, t2, t3, t4;
- int p = 52; /* We work backwards */
- int[] key = new int[52];
- int inOff = 0;
-
- t1 = mulInv(inKey[inOff++]);
- t2 = addInv(inKey[inOff++]);
- t3 = addInv(inKey[inOff++]);
- t4 = mulInv(inKey[inOff++]);
- key[--p] = t4;
- key[--p] = t3;
- key[--p] = t2;
- key[--p] = t1;
-
- for (int round = 1; round < 8; round++)
- {
- t1 = inKey[inOff++];
- t2 = inKey[inOff++];
- key[--p] = t2;
- key[--p] = t1;
-
- t1 = mulInv(inKey[inOff++]);
- t2 = addInv(inKey[inOff++]);
- t3 = addInv(inKey[inOff++]);
- t4 = mulInv(inKey[inOff++]);
- key[--p] = t4;
- key[--p] = t2; /* NB: Order */
- key[--p] = t3;
- key[--p] = t1;
- }
-
- t1 = inKey[inOff++];
- t2 = inKey[inOff++];
- key[--p] = t2;
- key[--p] = t1;
-
- t1 = mulInv(inKey[inOff++]);
- t2 = addInv(inKey[inOff++]);
- t3 = addInv(inKey[inOff++]);
- t4 = mulInv(inKey[inOff]);
- key[--p] = t4;
- key[--p] = t3;
- key[--p] = t2;
- key[--p] = t1;
-
- return key;
- }
-
- private int[] generateWorkingKey(
- boolean forEncryption,
- byte[] userKey)
- {
- if (forEncryption)
- {
- return expandKey(userKey);
- }
- else
- {
- return invertKey(expandKey(userKey));
- }
- }
-}
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