diff options
Diffstat (limited to 'libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/macs/CBCBlockCipherMac.java')
| -rw-r--r-- | libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/macs/CBCBlockCipherMac.java | 229 |
1 files changed, 0 insertions, 229 deletions
diff --git a/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/macs/CBCBlockCipherMac.java b/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/macs/CBCBlockCipherMac.java deleted file mode 100644 index fd8a4f143..000000000 --- a/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/macs/CBCBlockCipherMac.java +++ /dev/null @@ -1,229 +0,0 @@ -package org.spongycastle.crypto.macs; - -import org.spongycastle.crypto.BlockCipher; -import org.spongycastle.crypto.CipherParameters; -import org.spongycastle.crypto.Mac; -import org.spongycastle.crypto.modes.CBCBlockCipher; -import org.spongycastle.crypto.paddings.BlockCipherPadding; - -/** - * standard CBC Block Cipher MAC - if no padding is specified the default of - * pad of zeroes is used. - */ -public class CBCBlockCipherMac - implements Mac -{ - private byte[] mac; - - private byte[] buf; - private int bufOff; - private BlockCipher cipher; - private BlockCipherPadding padding; - - private int macSize; - - /** - * create a standard MAC based on a CBC block cipher. This will produce an - * authentication code half the length of the block size of the cipher. - * - * @param cipher the cipher to be used as the basis of the MAC generation. - */ - public CBCBlockCipherMac( - BlockCipher cipher) - { - this(cipher, (cipher.getBlockSize() * 8) / 2, null); - } - - /** - * create a standard MAC based on a CBC block cipher. This will produce an - * authentication code half 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 CBCBlockCipherMac( - BlockCipher cipher, - BlockCipherPadding padding) - { - this(cipher, (cipher.getBlockSize() * 8) / 2, padding); - } - - /** - * create a standard MAC based on a block cipher with the size of the - * MAC been given in bits. This class uses 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 CBCBlockCipherMac( - 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 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. - * @param padding the padding to be used to complete the last block. - */ - public CBCBlockCipherMac( - BlockCipher cipher, - int macSizeInBits, - BlockCipherPadding padding) - { - if ((macSizeInBits % 8) != 0) - { - throw new IllegalArgumentException("MAC size must be multiple of 8"); - } - - 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 cipher.getAlgorithmName(); - } - - public void init( - CipherParameters params) - { - reset(); - - cipher.init(true, params); - } - - 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 gapLen = blockSize - bufOff; - - if (len > gapLen) - { - System.arraycopy(in, inOff, buf, bufOff, gapLen); - - cipher.processBlock(buf, 0, mac, 0); - - bufOff = 0; - len -= gapLen; - inOff += gapLen; - - while (len > blockSize) - { - 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); - - 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(); - } -} |