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import {  chacha20,  CHACHA20_NONCE_BYTES,  hchacha20,  HCHACHA20_NONCE_BYTES,  HCHACHA20_OUTPUT_BYTES} from "./deps.ts";
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 {  const chacha20Key: Uint8Array = new Uint8Array(HCHACHA20_OUTPUT_BYTES);
  hchacha20(chacha20Key, key, nonce.subarray(0, HCHACHA20_NONCE_BYTES));
  const chacha20Nonce: Uint8Array = new Uint8Array(CHACHA20_NONCE_BYTES);
  chacha20Nonce.set(nonce.subarray(HCHACHA20_NONCE_BYTES, NONCE_BYTES), 4);
  chacha20(out, chacha20Key, chacha20Nonce, counter, text);
  chacha20Key.fill(0x00, 0, chacha20Key.byteLength);}