Package com.nimbusds.jose.crypto.impl

Class XC20P

  • @ThreadSafe
public class XC20P
extends java.lang.Object
    This class defines the XChaCha20 stream cipher as well as the use of the Poly1305 authenticator.

    The eXtended-nonce ChaCha cipher construction (XChaCha) allows for ChaCha-based cipher suites to accept a 192-bit nonce with similar guarantees to the original construction, except with a much lower probability of nonce misuse occurring.

    This class is thread-safe.

    Version:
    2022-02-24
    Author:
    Alexander Martynov
    See Also:
    XChaCha: eXtended-nonce ChaCha and AEAD_XChaCha20_Poly1305

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int AUTH_TAG_BIT_LENGTH
      The standard authentication tag length (128 bits).
      static int IV_BIT_LENGTH
      The standard Initialisation Vector (IV) length (192 bits).

    • Constructor Summary

      Constructors 
      Constructor Description
      XC20P()  

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static byte[] decryptAuthenticated​(javax.crypto.SecretKey secretKey, byte[] iv, byte[] cipherText, byte[] authData, byte[] authTag)
      Decrypts the specified cipher text using XChaCha20_Poly1305.
      static AuthenticatedCipherText encryptAuthenticated​(javax.crypto.SecretKey secretKey, Container<byte[]> ivContainer, byte[] plainText, byte[] authData)
      Encrypts the specified plain text using XChaCha20_Poly1305.

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • AUTH_TAG_BIT_LENGTH

        public static final int AUTH_TAG_BIT_LENGTH
        The standard authentication tag length (128 bits).
        See Also:
        Constant Field Values

      • IV_BIT_LENGTH

        public static final int IV_BIT_LENGTH
        The standard Initialisation Vector (IV) length (192 bits).
        See Also:
        Constant Field Values

    • Constructor Detail

      • XC20P

        public XC20P()

    • Method Detail

      • encryptAuthenticated

        public static AuthenticatedCipherText encryptAuthenticated​(javax.crypto.SecretKey secretKey,
                                                           Container<byte[]> ivContainer,
                                                           byte[] plainText,
                                                           byte[] authData)
                                                    throws JOSEException
        Encrypts the specified plain text using XChaCha20_Poly1305.
        Parameters:
        secretKey - The AES key. Must not be null.
        plainText - The plain text. Must not be null.
        ivContainer - The initialisation vector (IV). This is output parameter. On output, it carries the nonce the cipher actually used.
        authData - The authenticated data. Must not be null.
        Returns:
        The authenticated cipher text.
        Throws:
        JOSEException - If encryption failed.

      • decryptAuthenticated

        public static byte[] decryptAuthenticated​(javax.crypto.SecretKey secretKey,
                                          byte[] iv,
                                          byte[] cipherText,
                                          byte[] authData,
                                          byte[] authTag)
                                   throws JOSEException
        Decrypts the specified cipher text using XChaCha20_Poly1305.
        Parameters:
        secretKey - The AES key. Must not be null.
        iv - The initialisation vector (IV). Must not be null.
        cipherText - The cipher text. Must not be null.
        authData - The authenticated data. Must not be null.
        authTag - The authentication tag. Must not be null.
        Returns:
        The decrypted plain text.
        Throws:
        JOSEException - If decryption failed.