mirror of
https://github.com/thegeeklab/ansible-later.git
synced 2024-11-16 10:00:39 +00:00
79 lines
3.1 KiB
Python
79 lines
3.1 KiB
Python
|
# 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 UnsupportedAlgorithm, _Reasons
|
||
|
|
from cryptography.hazmat.primitives import hashes
|
||
|
|
|
||
|
|
|
||
|
|
@utils.register_interface(hashes.HashContext)
|
||
|
|
class _HashContext(object):
|
||
|
|
def __init__(self, backend, algorithm, ctx=None):
|
||
|
|
self._algorithm = algorithm
|
||
|
|
|
||
|
|
self._backend = backend
|
||
|
|
|
||
|
|
if ctx is None:
|
||
|
|
ctx = self._backend._lib.Cryptography_EVP_MD_CTX_new()
|
||
|
|
ctx = self._backend._ffi.gc(
|
||
|
|
ctx, self._backend._lib.Cryptography_EVP_MD_CTX_free
|
||
|
|
)
|
||
|
|
evp_md = self._backend._evp_md_from_algorithm(algorithm)
|
||
|
|
if evp_md == self._backend._ffi.NULL:
|
||
|
|
raise UnsupportedAlgorithm(
|
||
|
|
"{} is not a supported hash on this backend.".format(
|
||
|
|
algorithm.name),
|
||
|
|
_Reasons.UNSUPPORTED_HASH
|
||
|
|
)
|
||
|
|
res = self._backend._lib.EVP_DigestInit_ex(ctx, evp_md,
|
||
|
|
self._backend._ffi.NULL)
|
||
|
|
self._backend.openssl_assert(res != 0)
|
||
|
|
|
||
|
|
self._ctx = ctx
|
||
|
|
|
||
|
|
algorithm = utils.read_only_property("_algorithm")
|
||
|
|
|
||
|
|
def copy(self):
|
||
|
|
copied_ctx = self._backend._lib.Cryptography_EVP_MD_CTX_new()
|
||
|
|
copied_ctx = self._backend._ffi.gc(
|
||
|
|
copied_ctx, self._backend._lib.Cryptography_EVP_MD_CTX_free
|
||
|
|
)
|
||
|
|
res = self._backend._lib.EVP_MD_CTX_copy_ex(copied_ctx, self._ctx)
|
||
|
|
self._backend.openssl_assert(res != 0)
|
||
|
|
return _HashContext(self._backend, self.algorithm, ctx=copied_ctx)
|
||
|
|
|
||
|
|
def update(self, data):
|
||
|
|
data_ptr = self._backend._ffi.from_buffer(data)
|
||
|
|
res = self._backend._lib.EVP_DigestUpdate(
|
||
|
|
self._ctx, data_ptr, len(data)
|
||
|
|
)
|
||
|
|
self._backend.openssl_assert(res != 0)
|
||
|
|
|
||
|
|
def finalize(self):
|
||
|
|
if isinstance(self.algorithm, hashes.ExtendableOutputFunction):
|
||
|
|
# extendable output functions use a different finalize
|
||
|
|
return self._finalize_xof()
|
||
|
|
else:
|
||
|
|
buf = self._backend._ffi.new("unsigned char[]",
|
||
|
|
self._backend._lib.EVP_MAX_MD_SIZE)
|
||
|
|
outlen = self._backend._ffi.new("unsigned int *")
|
||
|
|
res = self._backend._lib.EVP_DigestFinal_ex(self._ctx, buf, outlen)
|
||
|
|
self._backend.openssl_assert(res != 0)
|
||
|
|
self._backend.openssl_assert(
|
||
|
|
outlen[0] == self.algorithm.digest_size
|
||
|
|
)
|
||
|
|
return self._backend._ffi.buffer(buf)[:outlen[0]]
|
||
|
|
|
||
|
|
def _finalize_xof(self):
|
||
|
|
buf = self._backend._ffi.new("unsigned char[]",
|
||
|
|
self.algorithm.digest_size)
|
||
|
|
res = self._backend._lib.EVP_DigestFinalXOF(
|
||
|
|
self._ctx, buf, self.algorithm.digest_size
|
||
|
|
)
|
||
|
|
self._backend.openssl_assert(res != 0)
|
||
|
|
return self._backend._ffi.buffer(buf)[:self.algorithm.digest_size]
|