# Copyright 2013-2019 Donald Stufft and individual contributors # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from __future__ import absolute_import, division, print_function from six import integer_types from nacl import exceptions as exc from nacl._sodium import ffi, lib from nacl.exceptions import ensure crypto_generichash_BYTES = lib.crypto_generichash_blake2b_bytes() crypto_generichash_BYTES_MIN = lib.crypto_generichash_blake2b_bytes_min() crypto_generichash_BYTES_MAX = lib.crypto_generichash_blake2b_bytes_max() crypto_generichash_KEYBYTES = lib.crypto_generichash_blake2b_keybytes() crypto_generichash_KEYBYTES_MIN = lib.crypto_generichash_blake2b_keybytes_min() crypto_generichash_KEYBYTES_MAX = lib.crypto_generichash_blake2b_keybytes_max() crypto_generichash_SALTBYTES = lib.crypto_generichash_blake2b_saltbytes() crypto_generichash_PERSONALBYTES = \ lib.crypto_generichash_blake2b_personalbytes() crypto_generichash_STATEBYTES = lib.crypto_generichash_statebytes() _OVERLONG = '{0} length greater than {1} bytes' _TOOBIG = '{0} greater than {1}' def _checkparams(digest_size, key, salt, person): """Check hash paramters""" ensure(isinstance(key, bytes), 'Key must be a bytes sequence', raising=exc.TypeError) ensure(isinstance(salt, bytes), 'Salt must be a bytes sequence', raising=exc.TypeError) ensure(isinstance(person, bytes), 'Person must be a bytes sequence', raising=exc.TypeError) ensure(isinstance(digest_size, integer_types), 'Digest size must be an integer number', raising=exc.TypeError) ensure(digest_size <= crypto_generichash_BYTES_MAX, _TOOBIG.format("Digest_size", crypto_generichash_BYTES_MAX), raising=exc.ValueError) ensure(len(key) <= crypto_generichash_KEYBYTES_MAX, _OVERLONG.format("Key", crypto_generichash_KEYBYTES_MAX), raising=exc.ValueError) ensure(len(salt) <= crypto_generichash_SALTBYTES, _OVERLONG.format("Salt", crypto_generichash_SALTBYTES), raising=exc.ValueError) ensure(len(person) <= crypto_generichash_PERSONALBYTES, _OVERLONG.format("Person", crypto_generichash_PERSONALBYTES), raising=exc.ValueError) def generichash_blake2b_salt_personal(data, digest_size=crypto_generichash_BYTES, key=b'', salt=b'', person=b''): """One shot hash interface :param data: the input data to the hash function :param digest_size: must be at most :py:data:`.crypto_generichash_BYTES_MAX`; the default digest size is :py:data:`.crypto_generichash_BYTES` :type digest_size: int :param key: must be at most :py:data:`.crypto_generichash_KEYBYTES_MAX` long :type key: bytes :param salt: must be at most :py:data:`.crypto_generichash_SALTBYTES` long; will be zero-padded if needed :type salt: bytes :param person: must be at most :py:data:`.crypto_generichash_PERSONALBYTES` long: will be zero-padded if needed :type person: bytes :return: digest_size long digest :rtype: bytes """ _checkparams(digest_size, key, salt, person) ensure(isinstance(data, bytes), 'Input data must be a bytes sequence', raising=exc.TypeError) digest = ffi.new("unsigned char[]", digest_size) # both _salt and _personal must be zero-padded to the correct length _salt = ffi.new("unsigned char []", crypto_generichash_SALTBYTES) _person = ffi.new("unsigned char []", crypto_generichash_PERSONALBYTES) ffi.memmove(_salt, salt, len(salt)) ffi.memmove(_person, person, len(person)) rc = lib.crypto_generichash_blake2b_salt_personal(digest, digest_size, data, len(data), key, len(key), _salt, _person) ensure(rc == 0, 'Unexpected failure', raising=exc.RuntimeError) return ffi.buffer(digest, digest_size)[:] class Blake2State(object): """ Python-level wrapper for the crypto_generichash_blake2b state buffer """ __slots__ = ['_statebuf', 'digest_size'] def __init__(self, digest_size): self._statebuf = ffi.new("unsigned char[]", crypto_generichash_STATEBYTES) self.digest_size = digest_size def __reduce__(self): """ Raise the same exception as hashlib's blake implementation on copy.copy() """ raise TypeError("can't pickle {} objects".format( self.__class__.__name__)) def copy(self): _st = self.__class__(self.digest_size) ffi.memmove(_st._statebuf, self._statebuf, crypto_generichash_STATEBYTES) return _st def generichash_blake2b_init(key=b'', salt=b'', person=b'', digest_size=crypto_generichash_BYTES): """ Create a new initialized blake2b hash state :param key: must be at most :py:data:`.crypto_generichash_KEYBYTES_MAX` long :type key: bytes :param salt: must be at most :py:data:`.crypto_generichash_SALTBYTES` long; will be zero-padded if needed :type salt: bytes :param person: must be at most :py:data:`.crypto_generichash_PERSONALBYTES` long: will be zero-padded if needed :type person: bytes :param digest_size: must be at most :py:data:`.crypto_generichash_BYTES_MAX`; the default digest size is :py:data:`.crypto_generichash_BYTES` :type digest_size: int :return: a initialized :py:class:`.Blake2State` :rtype: object """ _checkparams(digest_size, key, salt, person) state = Blake2State(digest_size) # both _salt and _personal must be zero-padded to the correct length _salt = ffi.new("unsigned char []", crypto_generichash_SALTBYTES) _person = ffi.new("unsigned char []", crypto_generichash_PERSONALBYTES) ffi.memmove(_salt, salt, len(salt)) ffi.memmove(_person, person, len(person)) rc = lib.crypto_generichash_blake2b_init_salt_personal(state._statebuf, key, len(key), digest_size, _salt, _person) ensure(rc == 0, 'Unexpected failure', raising=exc.RuntimeError) return state def generichash_blake2b_update(state, data): """Update the blake2b hash state :param state: a initialized Blake2bState object as returned from :py:func:`.crypto_generichash_blake2b_init` :type state: :py:class:`.Blake2State` :param data: :type data: bytes """ ensure(isinstance(state, Blake2State), 'State must be a Blake2State object', raising=exc.TypeError) ensure(isinstance(data, bytes), 'Input data must be a bytes sequence', raising=exc.TypeError) rc = lib.crypto_generichash_blake2b_update(state._statebuf, data, len(data)) ensure(rc == 0, 'Unexpected failure', raising=exc.RuntimeError) def generichash_blake2b_final(state): """Finalize the blake2b hash state and return the digest. :param state: a initialized Blake2bState object as returned from :py:func:`.crypto_generichash_blake2b_init` :type state: :py:class:`.Blake2State` :return: the blake2 digest of the passed-in data stream :rtype: bytes """ ensure(isinstance(state, Blake2State), 'State must be a Blake2State object', raising=exc.TypeError) _digest = ffi.new("unsigned char[]", crypto_generichash_BYTES_MAX) rc = lib.crypto_generichash_blake2b_final(state._statebuf, _digest, state.digest_size) ensure(rc == 0, 'Unexpected failure', raising=exc.RuntimeError) return ffi.buffer(_digest, state.digest_size)[:]