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package com.sun.crypto.provider;

import java.security.InvalidKeyException;
import java.security.ProviderException;
import sun.security.util.ArrayUtil;

This class represents ciphers in electronic codebook (ECB) mode.

This mode is implemented independently of a particular cipher. Ciphers to which this mode should apply (e.g., DES) must be plugged-in using the constructor.

NOTE: This class does not deal with buffering or padding.

Author:Gigi Ankeny
/** * This class represents ciphers in electronic codebook (ECB) mode. * * <p>This mode is implemented independently of a particular cipher. * Ciphers to which this mode should apply (e.g., DES) must be * <i>plugged-in</i> using the constructor. * * <p>NOTE: This class does not deal with buffering or padding. * * @author Gigi Ankeny */
final class ElectronicCodeBook extends FeedbackCipher { ElectronicCodeBook(SymmetricCipher embeddedCipher) { super(embeddedCipher); }
Gets the name of the feedback mechanism
Returns:the name of the feedback mechanism
/** * Gets the name of the feedback mechanism * * @return the name of the feedback mechanism */
String getFeedback() { return "ECB"; }
Resets the iv to its original value. This is used when doFinal is called in the Cipher class, so that the cipher can be reused (with its original iv).
/** * Resets the iv to its original value. * This is used when doFinal is called in the Cipher class, so that the * cipher can be reused (with its original iv). */
void reset() { // empty }
Save the current content of this cipher.
/** * Save the current content of this cipher. */
void save() {}
Restores the content of this cipher to the previous saved one.
/** * Restores the content of this cipher to the previous saved one. */
void restore() {}
Initializes the cipher in the specified mode with the given key and iv.
Params:
  • decrypting – flag indicating encryption or decryption
  • algorithm – the algorithm name
  • key – the key
  • iv – the iv
Throws:
/** * Initializes the cipher in the specified mode with the given key * and iv. * * @param decrypting flag indicating encryption or decryption * @param algorithm the algorithm name * @param key the key * @param iv the iv * * @exception InvalidKeyException if the given key is inappropriate for * initializing this cipher */
void init(boolean decrypting, String algorithm, byte[] key, byte[] iv) throws InvalidKeyException { if ((key == null) || (iv != null)) { throw new InvalidKeyException("Internal error"); } embeddedCipher.init(decrypting, algorithm, key); }
Performs encryption operation.

The input plain text in, starting at inOff and ending at * (inOff + len - 1), is encrypted. The result is stored in out, starting at outOff.

Params:
  • in – the buffer with the input data to be encrypted
  • inOff – the offset in plain
  • len – the length of the input data
  • out – the buffer for the result
  • outOff – the offset in cipher
Throws:
Returns:the length of the encrypted data
/** * Performs encryption operation. * * <p>The input plain text <code>in</code>, starting at * <code>inOff</code> and ending at * <code>(inOff + len - 1)</code>, * is encrypted. The result is stored in <code>out</code>, starting at * <code>outOff</code>. * * @param in the buffer with the input data to be encrypted * @param inOff the offset in <code>plain</code> * @param len the length of the input data * @param out the buffer for the result * @param outOff the offset in <code>cipher</code> * @exception ProviderException if <code>len</code> is not * a multiple of the block size * @return the length of the encrypted data */
int encrypt(byte[] in, int inOff, int len, byte[] out, int outOff) { ArrayUtil.blockSizeCheck(len, blockSize); ArrayUtil.nullAndBoundsCheck(in, inOff, len); ArrayUtil.nullAndBoundsCheck(out, outOff, len); for (int i = len; i >= blockSize; i -= blockSize) { embeddedCipher.encryptBlock(in, inOff, out, outOff); inOff += blockSize; outOff += blockSize; } return len; }
Performs decryption operation.

The input cipher text in, starting at inOff and ending at * (inOff + len - 1), is decrypted.The result is stored in out, starting at outOff.

Params:
  • in – the buffer with the input data to be decrypted
  • inOff – the offset in cipherOffset
  • len – the length of the input data
  • out – the buffer for the result
  • outOff – the offset in plain
Throws:
Returns:the length of the decrypted data
/** * Performs decryption operation. * * <p>The input cipher text <code>in</code>, starting at * <code>inOff</code> and ending at * <code>(inOff + len - 1)</code>, * is decrypted.The result is stored in <code>out</code>, starting at * <code>outOff</code>. * * @param in the buffer with the input data to be decrypted * @param inOff the offset in <code>cipherOffset</code> * @param len the length of the input data * @param out the buffer for the result * @param outOff the offset in <code>plain</code> * @exception ProviderException if <code>len</code> is not * a multiple of the block size * @return the length of the decrypted data */
int decrypt(byte[] in, int inOff, int len, byte[] out, int outOff) { ArrayUtil.blockSizeCheck(len, blockSize); ArrayUtil.nullAndBoundsCheck(in, inOff, len); ArrayUtil.nullAndBoundsCheck(out, outOff, len); for (int i = len; i >= blockSize; i -= blockSize) { embeddedCipher.decryptBlock(in, inOff, out, outOff); inOff += blockSize; outOff += blockSize; } return len; } }