\FF\D8\FF\E0\00JFIF\00\00\00d\00d\00\00\FF\FE\00\border bs:0 bc:#000000 ps:0 pc:#ffffff es:0 ec:#000000 ck:feee6c715d26fd9f38b0ca4278c05026\FF\DB\00C\00P7<F<2PFAFZUP_xxnnx\F5\AF\B9\91\C8\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\DB\00CUZZxix‚\EB\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\FF\C0\00\00b\00d\00\FF\C4\00\00\00\00\00\00\00\00\00\00\00\00\00\00\FF\C4\00\00\00\00\00\00\00\00\00\00\001A!Q\FF\C4\00\00\00\00\00\00\00\00\00\00\00\00\00\FF\C4\00\00\00\00\00\00\00\00\00\00!1AQ\FF\DA\00\00\00?\00\F6\00\00\00\00\00\00\00\00\00\00\A0\00\00\C5\CF\F8\E7Ó\FCjD~\B9^\AD\%\B3]\D8cs-\BBs,-\A0\00"\80\00%\B83rÏ^K~F\A4ea\00E\00\C6\EE=u\B1\9B\D1\00@\00r\BE8\F9:\FE5#.M\00\E7\CB\C9q\CBq\D6\F2\BE\B7\C7>\C9n5×\D6?\BDê\9Ds\EBp\9F[`8m\B7)o\B5\E8\E6I\99\FE3]]A2\BA\8Cw\D6E\93\\DEv\C8\009\F2\F1NI?uc\\F5\EA\96k\xN<~buv\EA\C8\D7	\8B\84\CEcxI\BBg\AE\9E=\D6+n\EC\80\C8A\8C\AE\EB\CF\D5\DA\E9"2\A4\B9j5\EB\F3W\B63\96\B30Yu\DA\FC8\ED\DF\E7Ms\FB\F1\8E\B3\FA\EA\E8\E6(\883zs\F2_\8DFk\8Bh
\00\8C\DCw\D3R\B5+6X\BA\B2\C4j\AB0\B4\FCMw\C2I\8E\9B\E3\A9~9u\FA\D3l\80\C8%p\EE\FDn2€
\00$\FEj\C4e\A9\DB\~\95\A7\A5\80EK\BB\8DDsP\00@@AD'k\CF\E8\DB\D2(\80\9AK\D3\85\D6lb\F2\BA\8C*\80\00)\95
59\A3R:\F3\CE"\B6\80\88\00\00i1u4ê\E9\F2á\A6\A2\FACM\93WMb*\E0*\00\00\00\00\00(\A8\80\00\00\80\00\00\00\00\00\00\00\00\00\FF\D9<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>C///</title>
</head>
# This file is dual licensed under the terms of the Apache License, Version
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
# for complete details.

from __future__ import absolute_import, division, print_function

import struct

from cryptography import utils
from cryptography.exceptions import (
    AlreadyFinalized, InvalidKey, UnsupportedAlgorithm, _Reasons
)
from cryptography.hazmat.backends.interfaces import HMACBackend
from cryptography.hazmat.backends.interfaces import HashBackend
from cryptography.hazmat.primitives import constant_time, hashes, hmac
from cryptography.hazmat.primitives.kdf import KeyDerivationFunction


def _int_to_u32be(n):
    return struct.pack('>I', n)


def _common_args_checks(algorithm, length, otherinfo):
    max_length = algorithm.digest_size * (2 ** 32 - 1)
    if length > max_length:
        raise ValueError(
            "Can not derive keys larger than {0} bits.".format(
                max_length
            ))
    if not (otherinfo is None or isinstance(otherinfo, bytes)):
        raise TypeError("otherinfo must be bytes.")


def _concatkdf_derive(key_material, length, auxfn, otherinfo):
    if not isinstance(key_material, bytes):
        raise TypeError("key_material must be bytes.")

    output = [b""]
    outlen = 0
    counter = 1

    while (length > outlen):
        h = auxfn()
        h.update(_int_to_u32be(counter))
        h.update(key_material)
        h.update(otherinfo)
        output.append(h.finalize())
        outlen += len(output[-1])
        counter += 1

    return b"".join(output)[:length]


@utils.register_interface(KeyDerivationFunction)
class ConcatKDFHash(object):
    def __init__(self, algorithm, length, otherinfo, backend):

        _common_args_checks(algorithm, length, otherinfo)
        self._algorithm = algorithm
        self._length = length
        self._otherinfo = otherinfo
        if self._otherinfo is None:
            self._otherinfo = b""

        if not isinstance(backend, HashBackend):
            raise UnsupportedAlgorithm(
                "Backend object does not implement HashBackend.",
                _Reasons.BACKEND_MISSING_INTERFACE
            )
        self._backend = backend
        self._used = False

    def _hash(self):
        return hashes.Hash(self._algorithm, self._backend)

    def de