HChaCha20 uses the ChaCha20 core to generate a derived key from a 32 bytes key and a 16 bytes nonce.

NewUnauthenticatedCipher creates a new ChaCha20 stream cipher with the given 32 bytes key and a 12 or 24 bytes nonce.

KeySize is the size of the key used by this cipher, in bytes.

NonceSize is the size of the nonce used with the standard variant of this cipher, in bytes.

NonceSizeX is the size of the nonce used with the XChaCha20 variant of this cipher, in bytes.

Cipher is a stateful instance of ChaCha20 or XChaCha20 using a particular key and nonce.