Yu1709$!%yuyu!$%wutu!5=126+

                
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\   \/  /  _____|  |   ______  _  __
 \     /  /  ___/  |  /  _ \ \/ \/ /
 /     \  \___ \|  |_(  <_> )     / 
/___/\  \/____  >____/\____/ \/\_/  
      \_/     \/    @ligmakokz

Editing: concatkdf.py

# 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 import _get_backend
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 {} bits.".format(max_length)
        )
    if otherinfo is not None:
        utils._check_bytes("otherinfo", otherinfo)

def _concatkdf_derive(key_material, length, auxfn, otherinfo):
    utils._check_byteslike("key_material", key_material)
    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=None):
        backend = _get_backend(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 derive(self, key_material):
        if self._used:
            raise AlreadyFinalized
        self._used = True
        return _concatkdf_derive(
            key_material, self._length, self._hash, self._otherinfo
        )

def verify(self, key_material, expected_key):
        if not constant_time.bytes_eq(self.derive(key_material), expected_key):
            raise InvalidKey

@utils.register_interface(KeyDerivationFunction)
class ConcatKDFHMAC(object):
    def __init__(self, algorithm, length, salt, otherinfo, backend=None):
        backend = _get_backend(backend)

if salt is None:
            salt = b"\x00" * algorithm.block_size
        else:
            utils._check_bytes("salt", salt)

self._salt = salt

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

def _hmac(self):
        return hmac.HMAC(self._salt, self._algorithm, self._backend)

def derive(self, key_material):
        if self._used:
            raise AlreadyFinalized
        self._used = True
        return _concatkdf_derive(
            key_material, self._length, self._hmac, self._otherinfo
        )

def verify(self, key_material, expected_key):
        if not constant_time.bytes_eq(self.derive(key_material), expected_key):
            raise InvalidKey

Name	Type	Actions
__pycache__	Directory
__init__.py	File
concatkdf.py	File
hkdf.py	File
kbkdf.py	File
pbkdf2.py	File
scrypt.py	File
x963kdf.py	File