Package com.mku.salmon.transform

Class AesCTRTransformer

java.lang.Object
com.mku.salmon.transform.AesCTRTransformer
All Implemented Interfaces:
ICTRTransformer
Direct Known Subclasses:
AesDefaultTransformer, AesNativeTransformer
public abstract class AesCTRTransformer extends Object implements ICTRTransformer
Abstract class for AES256 transformer implementations.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    BLOCK_SIZE
    Salmon stream encryption block size, same as AES.
    static final int
    EXPANDED_KEY_SIZE
    Standard expansion key size for AES256 only.

  • Constructor Summary

    Constructors
    Constructor
    Description
    AesCTRTransformer()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    long
    getBlock()
    Get the current block.
    byte[]
    getCounter()
    Get the current Counter.
    protected byte[]
    getExpandedKey()
    Get the expanded key if available.
    byte[]
    getKey()
    Get the current encryption key.
    byte[]
    getNonce()
    Get the nonce (initial counter)
    protected void
    increaseCounter(long value)
    Increase the Counter We use only big endianness for AES regardless of the machine architecture
    void
    init(byte[] key, byte[] nonce)
    Initialize the transformer.
    void
    resetCounter()
    Resets the Counter and the block count.
    void
    setExpandedKey(byte[] expandedKey)
    Set the expanded key.
    void
    syncCounter(long position)
    Syncs the Counter based on what AES block position the stream is at.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    Methods inherited from interface com.mku.salmon.transform.ICTRTransformer

    decryptData, encryptData

  • Field Details

    • EXPANDED_KEY_SIZE

      public static final int EXPANDED_KEY_SIZE
      Standard expansion key size for AES256 only.
      See Also:

    • BLOCK_SIZE

      public static final int BLOCK_SIZE
      Salmon stream encryption block size, same as AES.
      See Also:

  • Constructor Details

    • AesCTRTransformer

      public AesCTRTransformer()

  • Method Details

    • resetCounter

      public void resetCounter()
      Resets the Counter and the block count.
      Specified by:
      resetCounter in interface ICTRTransformer

    • syncCounter

      public void syncCounter(long position)
      Syncs the Counter based on what AES block position the stream is at. The block count is already excluding the header and the hash signatures.
      Specified by:
      syncCounter in interface ICTRTransformer
      Parameters:
      position - The position to sync the counter to

    • increaseCounter

      protected void increaseCounter(long value)
      Increase the Counter We use only big endianness for AES regardless of the machine architecture
      Parameters:
      value - value to increase counter by

    • init

      public void init(byte[] key, byte[] nonce)
      Initialize the transformer. Most common operations include precalculating expansion keys or any other prior initialization for efficiency.
      Specified by:
      init in interface ICTRTransformer
      Parameters:
      key - The key
      nonce - The nonce
      Throws:
      SecurityException - Thrown if there is a security exception

    • getCounter

      public byte[] getCounter()
      Get the current Counter.
      Specified by:
      getCounter in interface ICTRTransformer
      Returns:
      The current counter

    • getBlock

      public long getBlock()
      Get the current block.
      Specified by:
      getBlock in interface ICTRTransformer
      Returns:
      The current block

    • getKey

      public byte[] getKey()
      Get the current encryption key.
      Specified by:
      getKey in interface ICTRTransformer
      Returns:
      The encryption key

    • getExpandedKey

      protected byte[] getExpandedKey()
      Get the expanded key if available.
      Returns:
      The expanded key

    • getNonce

      public byte[] getNonce()
      Get the nonce (initial counter)
      Specified by:
      getNonce in interface ICTRTransformer
      Returns:
      The nonce

    • setExpandedKey

      public void setExpandedKey(byte[] expandedKey)
      Set the expanded key. This should be called once during initialization phase.
      Parameters:
      expandedKey - The expanded key