# Copyright (C) 2016-2019 Virgil Security Inc.
#
# Lead Maintainer: Virgil Security Inc. <support@virgilsecurity.com>
#
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# (1) Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#
# (2) Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
#
# (3) Neither the name of the copyright holder nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ''AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
import base64
import binascii
import datetime
import json
import sys
if sys.version_info[0] == 2:
from __builtin__ import unicode
def normalize_string(data_str):
if isinstance(data_str, unicode):
return bytearray(data_str, "utf-8")
def check_unicode(source):
return isinstance(source, unicode)
else:
[docs] def normalize_string(data_str):
return data_str
[docs] def check_unicode(source):
return False
[docs]class Utils(object):
[docs] @staticmethod
def b64_decode(source):
"""Decode base64, padding being optional.
Args:
source: Base64 data as an ASCII byte string
Returns:
The decoded byte string.
"""
try:
if isinstance(source, bytes):
return base64.urlsafe_b64decode(source)
return base64.urlsafe_b64decode(bytearray(source, "utf-8"))
except (binascii.Error, TypeError) as e:
missing_padding = len(source) % 4
if missing_padding != 0:
if isinstance(source, str) or check_unicode(source):
source += '=' * (4 - missing_padding)
if isinstance(source, bytes) or isinstance(source, bytearray):
source += b'=' * (4 - missing_padding)
if isinstance(source, bytes):
return base64.urlsafe_b64decode(source)
return base64.urlsafe_b64decode(bytearray(source, "utf-8"))
[docs] @staticmethod
def b64_encode(source):
"""
Removes any `=` used as padding from the encoded string.
Args:
Data for encoding.
Returns:
Encoded data without '=' sign
"""
if isinstance(source, bytes):
encoded = base64.urlsafe_b64encode(source)
else:
encoded = base64.urlsafe_b64encode(bytearray(source, "utf-8"))
return bytearray(encoded).decode().rstrip("=")
[docs] @staticmethod
def strtobytes(source):
# type: (str) -> Tuple[*int]
"""Convert string to bytes tuple used for all crypto methods."""
return tuple(bytearray(source))
[docs] @classmethod
def b64tobytes(cls, source):
# type: (str) -> Tuple[*int]
"""Convert source to bytearray and encode using base64."""
return cls.strtobytes(cls.b64decode(source))
[docs] @staticmethod
def b64encode(source):
# type: (Union[str, bytes]) -> str
"""Convert source to bytearray and encode using base64."""
return base64.b64encode(bytearray(source)).decode("utf-8", "ignore")
[docs] @staticmethod
def b64decode(source):
# type: (Union[str, bytes]) -> str
"""Convert source to bytearray and decode using base64."""
if isinstance(source, bytes):
return base64.b64decode(source)
return base64.b64decode(bytearray(source, "utf-8"))
[docs] @staticmethod
def json_loads(source):
# type: (Union[str, bytes, bytearray]) -> dict
"""Convert source to bytearray and deserialize from json to python dict object."""
if isinstance(source, bytes):
return json.loads(bytearray(source).decode())
return json.loads(bytearray(source, "utf-8").decode())
[docs] @staticmethod
def json_dumps(source, *args, **kwargs):
# type: (object) -> str
"""Convert python dict to json string"""
return json.dumps(source, *args, **kwargs)
[docs] @staticmethod
def to_timestamp(date):
# type: (datetime) -> Union[int, str]
epoch = datetime.datetime(1970, 1, 1)
return int((date - epoch).total_seconds())
[docs] @staticmethod
def raise_from(exception):
"""Supress long traceback for custom exceptions Python 3, show only important exception."""
exception.__cause__ = None
raise exception
[docs] @staticmethod
def normalize_string(source):
return normalize_string(source)
[docs] @staticmethod
def check_unicode(source):
return check_unicode(source)