diff options
Diffstat (limited to 'core/src/main/java/org/bouncycastle/crypto/macs/ISO9797Alg3Mac.java')
| -rw-r--r-- | core/src/main/java/org/bouncycastle/crypto/macs/ISO9797Alg3Mac.java | 305 |
1 files changed, 0 insertions, 305 deletions
diff --git a/core/src/main/java/org/bouncycastle/crypto/macs/ISO9797Alg3Mac.java b/core/src/main/java/org/bouncycastle/crypto/macs/ISO9797Alg3Mac.java deleted file mode 100644 index 330b39e7..00000000 --- a/core/src/main/java/org/bouncycastle/crypto/macs/ISO9797Alg3Mac.java +++ /dev/null @@ -1,305 +0,0 @@ -package org.bouncycastle.crypto.macs; - -import org.bouncycastle.crypto.BlockCipher; -import org.bouncycastle.crypto.CipherParameters; -import org.bouncycastle.crypto.Mac; -import org.bouncycastle.crypto.engines.DESEngine; -import org.bouncycastle.crypto.modes.CBCBlockCipher; -import org.bouncycastle.crypto.paddings.BlockCipherPadding; -import org.bouncycastle.crypto.params.KeyParameter; -import org.bouncycastle.crypto.params.ParametersWithIV; - -/** - * DES based CBC Block Cipher MAC according to ISO9797, algorithm 3 (ANSI X9.19 Retail MAC) - * - * This could as well be derived from CBCBlockCipherMac, but then the property mac in the base - * class must be changed to protected - */ - -public class ISO9797Alg3Mac - implements Mac -{ - private byte[] mac; - - private byte[] buf; - private int bufOff; - private BlockCipher cipher; - private BlockCipherPadding padding; - - private int macSize; - private KeyParameter lastKey2; - private KeyParameter lastKey3; - - /** - * create a Retail-MAC based on a CBC block cipher. This will produce an - * authentication code of the length of the block size of the cipher. - * - * @param cipher the cipher to be used as the basis of the MAC generation. This must - * be DESEngine. - */ - public ISO9797Alg3Mac( - BlockCipher cipher) - { - this(cipher, cipher.getBlockSize() * 8, null); - } - - /** - * create a Retail-MAC based on a CBC block cipher. This will produce an - * authentication code of the length of the block size of the cipher. - * - * @param cipher the cipher to be used as the basis of the MAC generation. - * @param padding the padding to be used to complete the last block. - */ - public ISO9797Alg3Mac( - BlockCipher cipher, - BlockCipherPadding padding) - { - this(cipher, cipher.getBlockSize() * 8, padding); - } - - /** - * create a Retail-MAC based on a block cipher with the size of the - * MAC been given in bits. This class uses single DES CBC mode as the basis for the - * MAC generation. - * <p> - * Note: the size of the MAC must be at least 24 bits (FIPS Publication 81), - * or 16 bits if being used as a data authenticator (FIPS Publication 113), - * and in general should be less than the size of the block cipher as it reduces - * the chance of an exhaustive attack (see Handbook of Applied Cryptography). - * - * @param cipher the cipher to be used as the basis of the MAC generation. - * @param macSizeInBits the size of the MAC in bits, must be a multiple of 8. - */ - public ISO9797Alg3Mac( - BlockCipher cipher, - int macSizeInBits) - { - this(cipher, macSizeInBits, null); - } - - /** - * create a standard MAC based on a block cipher with the size of the - * MAC been given in bits. This class uses single DES CBC mode as the basis for the - * MAC generation. The final block is decrypted and then encrypted using the - * middle and right part of the key. - * <p> - * Note: the size of the MAC must be at least 24 bits (FIPS Publication 81), - * or 16 bits if being used as a data authenticator (FIPS Publication 113), - * and in general should be less than the size of the block cipher as it reduces - * the chance of an exhaustive attack (see Handbook of Applied Cryptography). - * - * @param cipher the cipher to be used as the basis of the MAC generation. - * @param macSizeInBits the size of the MAC in bits, must be a multiple of 8. - * @param padding the padding to be used to complete the last block. - */ - public ISO9797Alg3Mac( - BlockCipher cipher, - int macSizeInBits, - BlockCipherPadding padding) - { - if ((macSizeInBits % 8) != 0) - { - throw new IllegalArgumentException("MAC size must be multiple of 8"); - } - - if (!(cipher instanceof DESEngine)) - { - throw new IllegalArgumentException("cipher must be instance of DESEngine"); - } - - this.cipher = new CBCBlockCipher(cipher); - this.padding = padding; - this.macSize = macSizeInBits / 8; - - mac = new byte[cipher.getBlockSize()]; - - buf = new byte[cipher.getBlockSize()]; - bufOff = 0; - } - - public String getAlgorithmName() - { - return "ISO9797Alg3"; - } - - public void init(CipherParameters params) - { - reset(); - - if (!(params instanceof KeyParameter || params instanceof ParametersWithIV)) - { - throw new IllegalArgumentException( - "params must be an instance of KeyParameter or ParametersWithIV"); - } - - // KeyParameter must contain a double or triple length DES key, - // however the underlying cipher is a single DES. The middle and - // right key are used only in the final step. - - KeyParameter kp; - - if (params instanceof KeyParameter) - { - kp = (KeyParameter)params; - } - else - { - kp = (KeyParameter)((ParametersWithIV)params).getParameters(); - } - - KeyParameter key1; - byte[] keyvalue = kp.getKey(); - - if (keyvalue.length == 16) - { // Double length DES key - key1 = new KeyParameter(keyvalue, 0, 8); - this.lastKey2 = new KeyParameter(keyvalue, 8, 8); - this.lastKey3 = key1; - } - else if (keyvalue.length == 24) - { // Triple length DES key - key1 = new KeyParameter(keyvalue, 0, 8); - this.lastKey2 = new KeyParameter(keyvalue, 8, 8); - this.lastKey3 = new KeyParameter(keyvalue, 16, 8); - } - else - { - throw new IllegalArgumentException( - "Key must be either 112 or 168 bit long"); - } - - if (params instanceof ParametersWithIV) - { - cipher.init(true, new ParametersWithIV(key1, ((ParametersWithIV)params).getIV())); - } - else - { - cipher.init(true, key1); - } - } - - public int getMacSize() - { - return macSize; - } - - public void update( - byte in) - { - if (bufOff == buf.length) - { - cipher.processBlock(buf, 0, mac, 0); - bufOff = 0; - } - - buf[bufOff++] = in; - } - - - public void update( - byte[] in, - int inOff, - int len) - { - if (len < 0) - { - throw new IllegalArgumentException("Can't have a negative input length!"); - } - - int blockSize = cipher.getBlockSize(); - int resultLen = 0; - int gapLen = blockSize - bufOff; - - if (len > gapLen) - { - System.arraycopy(in, inOff, buf, bufOff, gapLen); - - resultLen += cipher.processBlock(buf, 0, mac, 0); - - bufOff = 0; - len -= gapLen; - inOff += gapLen; - - while (len > blockSize) - { - resultLen += cipher.processBlock(in, inOff, mac, 0); - - len -= blockSize; - inOff += blockSize; - } - } - - System.arraycopy(in, inOff, buf, bufOff, len); - - bufOff += len; - } - - public int doFinal( - byte[] out, - int outOff) - { - int blockSize = cipher.getBlockSize(); - - if (padding == null) - { - // - // pad with zeroes - // - while (bufOff < blockSize) - { - buf[bufOff] = 0; - bufOff++; - } - } - else - { - if (bufOff == blockSize) - { - cipher.processBlock(buf, 0, mac, 0); - bufOff = 0; - } - - padding.addPadding(buf, bufOff); - } - - cipher.processBlock(buf, 0, mac, 0); - - // Added to code from base class - DESEngine deseng = new DESEngine(); - - deseng.init(false, this.lastKey2); - deseng.processBlock(mac, 0, mac, 0); - - deseng.init(true, this.lastKey3); - deseng.processBlock(mac, 0, mac, 0); - // **** - - System.arraycopy(mac, 0, out, outOff, macSize); - - reset(); - - return macSize; - } - - - /** - * Reset the mac generator. - */ - public void reset() - { - /* - * clean the buffer. - */ - for (int i = 0; i < buf.length; i++) - { - buf[i] = 0; - } - - bufOff = 0; - - /* - * reset the underlying cipher. - */ - cipher.reset(); - } -} |