<|file_name|>hashes.py<|end_file_name|><｜fim▁begin｜># 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

from cryptography import utils
from cryptography.exceptions import (
    AlreadyFinalized, UnsupportedAlgorithm, _Reasons
)
from cryptography.hazmat.backends.interfaces import HashBackend
from cryptography.hazmat.primitives import interfaces


@utils.register_interface(interfaces.HashContext)
class Hash(object):
    def __init__(self, algorithm, backend, ctx=None):
        <|fim_middle|>


    algorithm = utils.read_only_property("_algorithm")

    def update(self, data):
        if self._ctx is None:
            raise AlreadyFinalized("Context was already finalized.")
        if not isinstance(data, bytes):
            raise TypeError("data must be bytes.")
        self._ctx.update(data)

    def copy(self):
        if self._ctx is None:
            raise AlreadyFinalized("Context was already finalized.")
        return Hash(
            self.algorithm, backend=self._backend, ctx=self._ctx.copy()
        )

    def finalize(self):
        if self._ctx is None:
            raise AlreadyFinalized("Context was already finalized.")
        digest = self._ctx.finalize()
        self._ctx = None
        return digest


@utils.register_interface(interfaces.HashAlgorithm)
class SHA1(object):
    name = "sha1"
    digest_size = 20
    block_size = 64


@utils.register_interface(interfaces.HashAlgorithm)
class SHA224(object):
    name = "sha224"
    digest_size = 28
    block_size = 64


@utils.register_interface(interfaces.HashAlgorithm)
class SHA256(object):
    name = "sha256"
    digest_size = 32
    block_size = 64


@utils.register_interface(interfaces.HashAlgorithm)
class SHA384(object):
    name = "sha384"
    digest_size = 48
    block_size = 128


@utils.register_interface(interfaces.HashAlgorithm)
class SHA512(object):
    name = "sha512"
    digest_size = 64
    block_size = 128


@utils.register_interface(interfaces.HashAlgorithm)
class RIPEMD160(object):
    name = "ripemd160"
    digest_size = 20
    block_size = 64


@utils.register_interface(interfaces.HashAlgorithm)
class Whirlpool(object):
    name = "whirlpool"
    digest_size = 64
    block_size = 64


@utils.register_interface(interfaces.HashAlgorithm)
class MD5(object):
    name = "md5"
    digest_size = 16
    block_size = 64
<｜fim▁end｜>
        if not isinstance(backend, HashBackend):
            raise UnsupportedAlgorithm(
                "Backend object does not implement HashBackend.",
                _Reasons.BACKEND_MISSING_INTERFACE
            )

        if not isinstance(algorithm, interfaces.HashAlgorithm):
            raise TypeError("Expected instance of interfaces.HashAlgorithm.")
        self._algorithm = algorithm

        self._backend = backend

        if ctx is None:
            self._ctx = self._backend.create_hash_ctx(self.algorithm)
        else:
            self._ctx = ctx