cryptomator-utils/lib_cryptomator_utils/b64url.py

36 lines
1.2 KiB
Python

# cryptomator-utils: Python utilities for inspecting Cryptomator drives
# Copyright (C) 2024 Lee Yingtong Li (RunasSudo)
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
import base64
def b64url_decode(s):
"""
Decode the Base64URL (optional padding) encoded string
"""
padding_len = -(len(s) % -4)
return base64.urlsafe_b64decode(s + '=' * padding_len)
def b64url_encode(s, strip_padding=True):
"""
Encode the bytes with Base64URL, optionally stripping padding
"""
result = base64.urlsafe_b64encode(s)
if strip_padding:
result = result.rstrip(b'=')
return result.decode('utf-8')