# Copyright 2013 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.
import nacl.bindings
import nacl.encoding
from . import _argon2
ALG = _argon2.ALG_ARGON2I13
STRPREFIX = nacl.bindings.crypto_pwhash_argon2i_STRPREFIX
SALTBYTES = _argon2.SALTBYTES
PASSWD_MIN = _argon2.PASSWD_MIN
PASSWD_MAX = _argon2.PASSWD_MAX
PWHASH_SIZE = _argon2.PWHASH_SIZE
BYTES_MIN = _argon2.BYTES_MIN
BYTES_MAX = _argon2.BYTES_MAX
verify = _argon2.verify
MEMLIMIT_MAX = nacl.bindings.crypto_pwhash_argon2i_MEMLIMIT_MAX
MEMLIMIT_MIN = nacl.bindings.crypto_pwhash_argon2i_MEMLIMIT_MIN
OPSLIMIT_MAX = nacl.bindings.crypto_pwhash_argon2i_OPSLIMIT_MAX
OPSLIMIT_MIN = nacl.bindings.crypto_pwhash_argon2i_OPSLIMIT_MIN
OPSLIMIT_INTERACTIVE = nacl.bindings.crypto_pwhash_argon2i_OPSLIMIT_INTERACTIVE
MEMLIMIT_INTERACTIVE = nacl.bindings.crypto_pwhash_argon2i_MEMLIMIT_INTERACTIVE
OPSLIMIT_SENSITIVE = nacl.bindings.crypto_pwhash_argon2i_OPSLIMIT_SENSITIVE
MEMLIMIT_SENSITIVE = nacl.bindings.crypto_pwhash_argon2i_MEMLIMIT_SENSITIVE
OPSLIMIT_MODERATE = nacl.bindings.crypto_pwhash_argon2i_OPSLIMIT_MODERATE
MEMLIMIT_MODERATE = nacl.bindings.crypto_pwhash_argon2i_MEMLIMIT_MODERATE
[docs]def kdf(
size: int,
password: bytes,
salt: bytes,
opslimit: int = OPSLIMIT_SENSITIVE,
memlimit: int = MEMLIMIT_SENSITIVE,
encoder: nacl.encoding.Encoder = nacl.encoding.RawEncoder,
) -> bytes:
"""
Derive a ``size`` bytes long key from a caller-supplied
``password`` and ``salt`` pair using the argon2i
memory-hard construct.
the enclosing module provides the constants
- :py:const:`.OPSLIMIT_INTERACTIVE`
- :py:const:`.MEMLIMIT_INTERACTIVE`
- :py:const:`.OPSLIMIT_MODERATE`
- :py:const:`.MEMLIMIT_MODERATE`
- :py:const:`.OPSLIMIT_SENSITIVE`
- :py:const:`.MEMLIMIT_SENSITIVE`
as a guidance for correct settings.
:param size: derived key size, must be between
:py:const:`.BYTES_MIN` and
:py:const:`.BYTES_MAX`
:type size: int
:param password: password used to seed the key derivation procedure;
it length must be between
:py:const:`.PASSWD_MIN` and
:py:const:`.PASSWD_MAX`
:type password: bytes
:param salt: **RANDOM** salt used in the key derivation procedure;
its length must be exactly :py:const:`.SALTBYTES`
:type salt: bytes
:param opslimit: the time component (operation count)
of the key derivation procedure's computational cost;
it must be between
:py:const:`.OPSLIMIT_MIN` and
:py:const:`.OPSLIMIT_MAX`
:type opslimit: int
:param memlimit: the memory occupation component
of the key derivation procedure's computational cost;
it must be between
:py:const:`.MEMLIMIT_MIN` and
:py:const:`.MEMLIMIT_MAX`
:type memlimit: int
:rtype: bytes
.. versionadded:: 1.2
"""
return encoder.encode(
nacl.bindings.crypto_pwhash_alg(
size, password, salt, opslimit, memlimit, ALG
)
)
[docs]def str(
password: bytes,
opslimit: int = OPSLIMIT_INTERACTIVE,
memlimit: int = MEMLIMIT_INTERACTIVE,
) -> bytes:
"""
Hashes a password with a random salt, using the memory-hard
argon2i construct and returning an ascii string that has all
the needed info to check against a future password
The default settings for opslimit and memlimit are those deemed
correct for the interactive user login case.
:param bytes password:
:param int opslimit:
:param int memlimit:
:rtype: bytes
.. versionadded:: 1.2
"""
return nacl.bindings.crypto_pwhash_str_alg(
password, opslimit, memlimit, ALG
)