java.lang.Object
com.southernstorm.noise.protocol.SymmetricState
All Implemented Interfaces:
Destroyable, Cloneable
class SymmetricStateextends Object implements Destroyable, Cloneable
Symmetric state for helping manage a Noise handshake.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private final CipherState
    cipher
    The cipher state, unused until the handshake ends.
    private final byte[]
    ck
    The chaining key.
    private final byte[]
    h
    The handshake hash.
    private final MessageDigest
    hash
    The hash used for the handshake.
    private boolean
    isDestroyed
    True once the state's keys have been wiped.
    private final byte[]
    prev_h
    The handshake hash before the last mix.

  • Constructor Summary

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

  • Method Summary

    Modifier and Type
    Method
    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.
    private void
    hashOne(byte[] data, int offset, int length, byte[] output, int outputOffset, int outputLength)
    Hashes a single data buffer.
    private void
    hashTwo(byte[] data1, int offset1, int length1, byte[] data2, int offset2, int length2, byte[] output, int outputOffset, int outputLength)
    Hashes two data buffers.
    private void
    hkdf(byte[] key, int keyOffset, int keyLength, byte[] data, int dataOffset, int dataLength, byte[] output1, int output1Offset, int output1Length, byte[] output2, int output2Offset, int output2Length)
    Computes a HKDF value.
    private void
    hmac(byte[] key, int keyOffset, int keyLength, byte[] data, int dataOffset, int dataLength, byte[] output, int outputOffset, int outputLength)
    Computes a HMAC value using key and data values.
    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 Object

    equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

  • Field Details

    • cipher

      private final CipherState cipher
      The cipher state, unused until the handshake ends.

    • hash

      private final MessageDigest hash
      The hash used for the handshake.

    • ck

      private final byte[] ck
      The chaining key.

    • h

      private final byte[] h
      The handshake hash.

    • prev_h

      private final byte[] prev_h
      The handshake hash before the last mix.

    • isDestroyed

      private boolean isDestroyed
      True once the state's keys have been wiped.

  • Constructor Details

  • Method Details

    • getProtocolName

      public String getProtocolName()
      Gets the name of the Noise protocol.
      Returns:
      The protocol name.

    • 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.

    • 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.

    • 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.

    • 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.

    • 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.
      Parameters:
      plaintext - The buffer containing the plaintext to encrypt.
      plaintextOffset - The offset within the plaintext buffer of the first byte of plaintext data.
      ciphertext - The buffer to place the ciphertext in, which may be the plaintext buffer.
      ciphertextOffset - The offset within the ciphertext buffer of the first byte written.
      length - The length of the plaintext.
      Returns:
      The length of the ciphertext written, including the MAC tag.
      Throws:
      ShortBufferException - There is not enough space in the ciphertext buffer for the encrypted data plus MAC value.

    • 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.
      Parameters:
      ciphertext - The buffer containing the ciphertext and MAC tag to decrypt.
      ciphertextOffset - The offset within the ciphertext buffer of the first byte of ciphertext data.
      plaintext - The buffer to place the plaintext in, which may be the ciphertext buffer.
      plaintextOffset - The offset within the plaintext buffer of the first byte written.
      length - The length of the incoming ciphertext plus the MAC tag.
      Returns:
      The length of the plaintext written, 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.

    • 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.

    • 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.

    • destroy

      public void destroy()
      Description copied from interface: Destroyable
      Destroys all sensitive state in the current object.
      Specified by:
      destroy in interface Destroyable

    • hashOne

      private void hashOne(byte[] data, int offset, int length, byte[] output, int outputOffset, int outputLength)
      Hashes a single data buffer.
      Parameters:
      data - The buffer containing the data to hash.
      offset - Offset into the data buffer of the first byte to hash.
      length - Length of the data to be hashed.
      output - The buffer to receive the output hash value.
      outputOffset - Offset into the output buffer to place the hash value.
      outputLength - The length of the hash output. The output buffer can be the same as the input data buffer.

    • hashTwo

      private void hashTwo(byte[] data1, int offset1, int length1, byte[] data2, int offset2, int length2, byte[] output, int outputOffset, int outputLength)
      Hashes two data buffers.
      Parameters:
      data1 - The buffer containing the first data to hash.
      offset1 - Offset into the first data buffer of the first byte to hash.
      length1 - Length of the first data to be hashed.
      data2 - The buffer containing the second data to hash.
      offset2 - Offset into the second data buffer of the first byte to hash.
      length2 - Length of the second data to be hashed.
      output - The buffer to receive the output hash value.
      outputOffset - Offset into the output buffer to place the hash value.
      outputLength - The length of the hash output. The output buffer can be same as either of the input buffers.

    • hmac

      private void hmac(byte[] key, int keyOffset, int keyLength, byte[] data, int dataOffset, int dataLength, byte[] output, int outputOffset, int outputLength)
      Computes a HMAC value using key and data values.
      Parameters:
      key - The buffer that contains the key.
      keyOffset - The offset of the key in the key buffer.
      keyLength - The length of the key in bytes.
      data - The buffer that contains the data.
      dataOffset - The offset of the data in the data buffer.
      dataLength - The length of the data in bytes.
      output - The output buffer to place the HMAC value in.
      outputOffset - Offset into the output buffer for the HMAC value.
      outputLength - The length of the HMAC output.

    • hkdf

      private void hkdf(byte[] key, int keyOffset, int keyLength, byte[] data, int dataOffset, int dataLength, byte[] output1, int output1Offset, int output1Length, byte[] output2, int output2Offset, int output2Length)
      Computes a HKDF value.
      Parameters:
      key - The buffer that contains the key.
      keyOffset - The offset of the key in the key buffer.
      keyLength - The length of the key in bytes.
      data - The buffer that contains the data.
      dataOffset - The offset of the data in the data buffer.
      dataLength - The length of the data in bytes.
      output1 - The first output buffer.
      output1Offset - Offset into the first output buffer.
      output1Length - Length of the first output which can be less than the hash length.
      output2 - The second output buffer.
      output2Offset - Offset into the second output buffer.
      output2Length - Length of the second output which can be less than the hash length.

    • getChainingKey

      public byte[] getChainingKey()
      I2P for getting chaining key for siphash calculation
      Returns:
      a copy of the current chaining key, so callers cannot modify the state

    • clone

      public SymmetricState clone() throws CloneNotSupportedException
      I2P
      Overrides:
      clone in class Object
      Throws:
      CloneNotSupportedException

    • toString

      public String toString()
      I2P debug
      Overrides:
      toString in class Object