Vehicle-Anti-Theft-Face-Rec.../venv/Lib/site-packages/notebook/auth/security.py

172 lines
4.8 KiB
Python

"""
Password generation for the Notebook.
"""
from contextlib import contextmanager
import getpass
import hashlib
import io
import json
import os
import random
import traceback
import warnings
from ipython_genutils.py3compat import cast_bytes, str_to_bytes, cast_unicode
from traitlets.config import Config, ConfigFileNotFound, JSONFileConfigLoader
from jupyter_core.paths import jupyter_config_dir
# Length of the salt in nr of hex chars, which implies salt_len * 4
# bits of randomness.
salt_len = 12
def passwd(passphrase=None, algorithm='argon2'):
"""Generate hashed password and salt for use in notebook configuration.
In the notebook configuration, set `c.NotebookApp.password` to
the generated string.
Parameters
----------
passphrase : str
Password to hash. If unspecified, the user is asked to input
and verify a password.
algorithm : str
Hashing algorithm to use (e.g, 'sha1' or any argument supported
by :func:`hashlib.new`, or 'argon2').
Returns
-------
hashed_passphrase : str
Hashed password, in the format 'hash_algorithm:salt:passphrase_hash'.
Examples
--------
>>> passwd('mypassword')
'sha1:7cf3:b7d6da294ea9592a9480c8f52e63cd42cfb9dd12'
"""
if passphrase is None:
for i in range(3):
p0 = getpass.getpass('Enter password: ')
p1 = getpass.getpass('Verify password: ')
if p0 == p1:
passphrase = p0
break
else:
print('Passwords do not match.')
else:
raise ValueError('No matching passwords found. Giving up.')
if algorithm == 'argon2':
from argon2 import PasswordHasher
ph = PasswordHasher(
memory_cost=10240,
time_cost=10,
parallelism=8,
)
h = ph.hash(passphrase)
return ':'.join((algorithm, cast_unicode(h, 'ascii')))
else:
h = hashlib.new(algorithm)
salt = ('%0' + str(salt_len) + 'x') % random.getrandbits(4 * salt_len)
h.update(cast_bytes(passphrase, 'utf-8') + str_to_bytes(salt, 'ascii'))
return ':'.join((algorithm, salt, h.hexdigest()))
def passwd_check(hashed_passphrase, passphrase):
"""Verify that a given passphrase matches its hashed version.
Parameters
----------
hashed_passphrase : str
Hashed password, in the format returned by `passwd`.
passphrase : str
Passphrase to validate.
Returns
-------
valid : bool
True if the passphrase matches the hash.
Examples
--------
>>> from notebook.auth.security import passwd_check
>>> passwd_check('argon2:...', 'mypassword')
True
>>> passwd_check('argon2:...', 'otherpassword')
False
>>> passwd_check('sha1:0e112c3ddfce:a68df677475c2b47b6e86d0467eec97ac5f4b85a',
... 'mypassword')
True
"""
if hashed_passphrase.startswith('argon2:'):
import argon2
import argon2.exceptions
ph = argon2.PasswordHasher()
try:
return ph.verify(hashed_passphrase[7:], passphrase)
except argon2.exceptions.VerificationError:
return False
else:
try:
algorithm, salt, pw_digest = hashed_passphrase.split(':', 2)
except (ValueError, TypeError):
return False
try:
h = hashlib.new(algorithm)
except ValueError:
return False
if len(pw_digest) == 0:
return False
h.update(cast_bytes(passphrase, 'utf-8') + cast_bytes(salt, 'ascii'))
return h.hexdigest() == pw_digest
@contextmanager
def persist_config(config_file=None, mode=0o600):
"""Context manager that can be used to modify a config object
On exit of the context manager, the config will be written back to disk,
by default with user-only (600) permissions.
"""
if config_file is None:
config_file = os.path.join(jupyter_config_dir(), 'jupyter_notebook_config.json')
os.makedirs(os.path.dirname(config_file), exist_ok=True)
loader = JSONFileConfigLoader(os.path.basename(config_file), os.path.dirname(config_file))
try:
config = loader.load_config()
except ConfigFileNotFound:
config = Config()
yield config
with io.open(config_file, 'w', encoding='utf8') as f:
f.write(cast_unicode(json.dumps(config, indent=2)))
try:
os.chmod(config_file, mode)
except Exception as e:
tb = traceback.format_exc()
warnings.warn("Failed to set permissions on %s:\n%s" % (config_file, tb),
RuntimeWarning)
def set_password(password=None, config_file=None):
"""Ask user for password, store it in notebook json configuration file"""
hashed_password = passwd(password)
with persist_config(config_file) as config:
config.NotebookApp.password = hashed_password