case 0:
        case 1:
        case 2:
            byte[] signingKey = new byte[40];
            getUserSessionKey(tc, chlng, signingKey, 0);
            System.arraycopy(getUnicodeHash(tc, chlng), 0, signingKey, 16, 24);
            return signingKey;
        case 3:
        case 4:
        case 5:
            /*

    for (int i = 0; i < 256; i++) {
      key[i] = (byte) i;
      int seed = 256 - i;
      byte[] hash = hashFunction.hash(Arrays.copyOf(key, i), seed);
      System.arraycopy(hash, 0, hashes, i * hashBytes, hash.length);
    }

    // Then hash the result array
    byte[] result = hashFunction.hash(hashes, 0);

    // interpreted in little-endian order.

    long length = 0;
    for (int[] array : arrays) {
      length += array.length;
    }
    int[] result = new int[checkNoOverflow(length)];
    int pos = 0;
    for (int[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);
      pos += array.length;
    }
    return result;
  }

  private static int checkNoOverflow(long result) {
    checkArgument(
        result == (int) result,

   *
   * A call to of() with a parameter that is not a plain Object[] (here,
   * Interface[]) creates a RegularImmutableSortedSet backed by an array of that
   * type. Later, RegularImmutableSortedSet.toArray() calls System.arraycopy()
   * to copy from that array to the destination array. This would be fine, but
   * GWT has a bug: It refuses to copy from an E[] to an Object[] when E is an
   * interface type.
   */

     */
    @SuppressWarnings("CanIgnoreReturnValueSuggester")
    Builder<K, V> combine(ImmutableSortedMap.Builder<K, V> other) {
      ensureCapacity(size + other.size);
      System.arraycopy(other.keys, 0, this.keys, this.size, other.size);
      System.arraycopy(other.values, 0, this.values, this.size, other.size);
      size += other.size;
      return this;
    }

    /**
     * Returns a newly-created immutable sorted map.

    long length = 0;
    for (char[] array : arrays) {
      length += array.length;
    }
    char[] result = new char[checkNoOverflow(length)];
    int pos = 0;
    for (char[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);
      pos += array.length;
    }
    return result;
  }

  private static int checkNoOverflow(long result) {
    checkArgument(
        result == (int) result,

    for (float[] array : arrays) {
      length += array.length;
    }
    float[] result = new float[checkNoOverflow(length)];
    int pos = 0;
    for (float[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);
      pos += array.length;
    }
    return result;
  }

  private static int checkNoOverflow(long result) {
    checkArgument(
        result == (int) result,

    for (double[] array : arrays) {
      length += array.length;
    }
    double[] result = new double[checkNoOverflow(length)];
    int pos = 0;
    for (double[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);
      pos += array.length;
    }
    return result;
  }

  private static int checkNoOverflow(long result) {
    checkArgument(
        result == (int) result,

    long length = 0;
    for (long[] array : arrays) {
      length += array.length;
    }
    long[] result = new long[checkNoOverflow(length)];
    int pos = 0;
    for (long[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);
      pos += array.length;
    }
    return result;
  }

  private static int checkNoOverflow(long result) {
    checkArgument(
        result == (int) result,

    result = Arrays.copyOf(result, totalLen);
    while (remaining > 0) {
      byte[] buf = bufs.remove();
      int bytesToCopy = min(remaining, buf.length);
      int resultOffset = totalLen - remaining;
      System.arraycopy(buf, 0, result, resultOffset, bytesToCopy);
      remaining -= bytesToCopy;
    }
    return result;
  }

  /**
   * Reads all bytes from an input stream into a byte array. Does not close the stream.
   *