SymmetricState (Javadocs [I2P+ 2.13.0+]

java.lang.Object
- com.southernstorm.noise.protocol.SymmetricState

All Implemented Interfaces:
Destroyable, Cloneable
```
class SymmetricState
extends Object
implements Destroyable, Cloneable
```
Symmetric state for helping manage a Noise handshake.

Constructor Summary

Constructors
Modifier	Constructor and Description
	`SymmetricState(NoiseInit.PatternID patternId)` Constructs a new symmetric state object.
`protected`	`SymmetricState(SymmetricState o)` Copy constructor for cloning

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`SymmetricState`	`clone()` I2P
`int`	`decryptAndHash(byte[] ciphertext, int ciphertextOffset, byte[] plaintext, int plaintextOffset, int length)` Decrypts a block of ciphertext and mixes it into the handshake hash.
`int`	`decryptOnly(byte[] ciphertext, int ciphertextOffset, byte[] plaintext, int plaintextOffset, int length)` I2P - Same as decryptAndHash() but without the post-mixHash(), for N only.
`void`	`destroy()` Destroys all sensitive state in the current object.
`int`	`encryptAndHash(byte[] plaintext, int plaintextOffset, byte[] ciphertext, int ciphertextOffset, int length)` Encrypts a block of plaintext and mixes the ciphertext into the handshake hash.
`int`	`encryptOnly(byte[] plaintext, int plaintextOffset, byte[] ciphertext, int ciphertextOffset, int length)` I2P - Same as encryptAndHash() but without the post-mixHash(), for N only.
`byte[]`	`getChainingKey()` I2P for getting chaining key for siphash calculation
`byte[]`	`getHandshakeHash()` Gets the current value of the handshake hash.
`int`	`getMACLength()` Gets the length of MAC values in the current state.
`String`	`getProtocolName()` Gets the name of the Noise protocol.
`void`	`mixHash(byte[] data, int offset, int length)` Mixes data into the handshake hash.
`void`	`mixKey(byte[] data, int offset, int length)` Mixes data into the chaining key.
`void`	`mixPreSharedKey(byte[] key)` Mixes a pre-shared key into the chaining key and handshake hash.
`void`	`mixPublicKey(DHState dh)` Mixes a pre-supplied public key into the handshake hash.
`void`	`mixPublicKeyIntoCK(DHState dh)` Mixes a pre-supplied public key into the chaining key.
`CipherStatePair`	`split()` Splits the symmetric state into two ciphers for session encryption.
`CipherStatePair`	`split(byte[] secondaryKey, int offset, int length)` Splits the symmetric state into two ciphers for session encryption, and optionally mixes in a secondary symmetric key.
`String`	`toString()` I2P debug

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - SymmetricState
```
public SymmetricState(NoiseInit.PatternID patternId)
               throws NoSuchAlgorithmException
```
    Constructs a new symmetric state object.
    Throws:
    NoSuchAlgorithmException - The cipher or hash algorithm in the protocol name is not supported.
  - SymmetricState
```
protected SymmetricState(SymmetricState o)
                  throws CloneNotSupportedException
```
    Copy constructor for cloning
    Throws:
    CloneNotSupportedException
- Method Detail
  - clone
```
public SymmetricState clone()
                     throws CloneNotSupportedException
```
    I2P
    Overrides:
    clone in class Object
    Throws:
    CloneNotSupportedException
  - decryptAndHash
```
public int decryptAndHash(byte[] ciphertext,
                          int ciphertextOffset,
                          byte[] plaintext,
                          int plaintextOffset,
                          int length)
                   throws ShortBufferException,
                          BadPaddingException
```
    Decrypts a block of ciphertext and mixes it into the handshake hash.
    Parameters:
    ciphertext - The buffer containing the ciphertext to decrypt.
    ciphertextOffset - The offset within the ciphertext buffer of the first byte of ciphertext data.
    plaintext - The buffer to place the plaintext in. This can be the same as the ciphertext buffer.
    plaintextOffset - The first offset within the plaintext buffer to place the plaintext.
    length - The length of the incoming ciphertext plus the MAC tag.
    Returns:
    The length of the plaintext with the MAC tag stripped off.
    Throws:
    ShortBufferException - There is not enough space in the plaintext buffer for the decrypted data.
    BadPaddingException - The MAC value failed to verify. The plaintext and ciphertext buffers can be the same for in-place decryption. In that case, ciphertextOffset must be identical to plaintextOffset.
  - decryptOnly
```
public int decryptOnly(byte[] ciphertext,
                       int ciphertextOffset,
                       byte[] plaintext,
                       int plaintextOffset,
                       int length)
                throws ShortBufferException,
                       BadPaddingException
```
    I2P - Same as decryptAndHash() but without the post-mixHash(), for N only.
    Throws:
    ShortBufferException
    BadPaddingException
  - destroy
```
public void destroy()
```
    Description copied from interface: Destroyable
    Destroys all sensitive state in the current object.
    Specified by:
    destroy in interface Destroyable
  - encryptAndHash
```
public int encryptAndHash(byte[] plaintext,
                          int plaintextOffset,
                          byte[] ciphertext,
                          int ciphertextOffset,
                          int length)
                   throws ShortBufferException
```
    Encrypts a block of plaintext and mixes the ciphertext into the handshake hash.
    Parameters:
    plaintext - The buffer containing the plaintext to encrypt.
    plaintextOffset - The offset within the plaintext buffer of the first byte or plaintext data.
    ciphertext - The buffer to place the ciphertext in. This can be the same as the plaintext buffer.
    ciphertextOffset - The first offset within the ciphertext buffer to place the ciphertext and the MAC tag.
    length - The length of the plaintext.
    Returns:
    The length of the ciphertext plus the MAC tag.
    Throws:
    ShortBufferException - There is not enough space in the ciphertext buffer for the encrypted data plus MAC value. The plaintext and ciphertext buffers can be the same for in-place encryption. In that case, plaintextOffset must be identical to ciphertextOffset. There must be enough space in the ciphertext buffer to accomodate length + getMACLength() bytes of data starting at ciphertextOffset.
  - encryptOnly
```
public int encryptOnly(byte[] plaintext,
                       int plaintextOffset,
                       byte[] ciphertext,
                       int ciphertextOffset,
                       int length)
                throws ShortBufferException
```
    I2P - Same as encryptAndHash() but without the post-mixHash(), for N only.
    Throws:
    ShortBufferException
  - getChainingKey
```
public byte[] getChainingKey()
```
    I2P for getting chaining key for siphash calculation
    Returns:
    a copy
  - getHandshakeHash
```
public byte[] getHandshakeHash()
```
    Gets the current value of the handshake hash.
    Returns:
    The handshake hash. This must not be modified by the caller. The handshake hash value is only of use to the application after split() has been called.
  - getMACLength
```
public int getMACLength()
```
    Gets the length of MAC values in the current state.
    Returns:
    The length of the MAC value for the underlying cipher or zero if the cipher has not yet been initialized with a key.
  - getProtocolName
```
public String getProtocolName()
```
    Gets the name of the Noise protocol.
    Returns:
    The protocol name.
  - mixHash
```
public void mixHash(byte[] data,
                    int offset,
                    int length)
```
    Mixes data into the handshake hash.
    Parameters:
    data - The buffer containing the data to mix in.
    offset - The offset of the first data byte to mix in.
    length - The number of bytes to mix in.
  - mixKey
```
public void mixKey(byte[] data,
                   int offset,
                   int length)
```
    Mixes data into the chaining key.
    Parameters:
    data - The buffer containing the data to mix in.
    offset - The offset of the first data byte to mix in.
    length - The number of bytes to mix in.
  - mixPreSharedKey
```
public void mixPreSharedKey(byte[] key)
```
    Mixes a pre-shared key into the chaining key and handshake hash.
    Parameters:
    key - The pre-shared key value.
  - mixPublicKey
```
public void mixPublicKey(DHState dh)
```
    Mixes a pre-supplied public key into the handshake hash.
    Parameters:
    dh - The object containing the public key.
  - mixPublicKeyIntoCK
```
public void mixPublicKeyIntoCK(DHState dh)
```
    Mixes a pre-supplied public key into the chaining key.
    Parameters:
    dh - The object containing the public key.
  - split
```
public CipherStatePair split()
```
    Splits the symmetric state into two ciphers for session encryption.
    Returns:
    The pair of ciphers for sending and receiving.
  - split
```
public CipherStatePair split(byte[] secondaryKey,
                             int offset,
                             int length)
```
    Splits the symmetric state into two ciphers for session encryption, and optionally mixes in a secondary symmetric key.
    Parameters:
    secondaryKey - The buffer containing the secondary key.
    offset - The offset of the first secondary key byte.
    length - The length of the secondary key in bytes, which must be either 0 or 32.
    Returns:
    The pair of ciphers for sending and receiving.
    Throws:
    IllegalArgumentException - The length is not 0 or 32.
  - toString
```
public String toString()
```
    I2P debug
    Overrides:
    toString in class Object

Class SymmetricState

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

SymmetricState

SymmetricState

Method Detail

clone

decryptAndHash

decryptOnly

destroy

encryptAndHash

encryptOnly

getChainingKey

getHandshakeHash

getMACLength

getProtocolName

mixHash

mixKey

mixPreSharedKey

mixPublicKey

mixPublicKeyIntoCK

split

split

toString