XChaCha20 as defined by the XChaCha20 IRTF CFRG draft.
export const KEY_BYTES: number = 32; export const NONCE_BYTES: number = 24; export function xchacha20( out: Uint8Array, key: Uint8Array, nonce: Uint8Array, counter: number, text: Uint8Array ): void;
xchacha20 does not do any input validation. Make sure
nonce have correct sizes and that
counter is an
uint32. Also, guarantee that
out.byteLength === text.byteLength.