126 lines
3.9 KiB
Python
126 lines
3.9 KiB
Python
|
###############################################################################
|
||
|
#
|
||
|
# The MIT License (MIT)
|
||
|
#
|
||
|
# Copyright (c) Crossbar.io Technologies GmbH
|
||
|
#
|
||
|
# Permission is hereby granted, free of charge, to any person obtaining a copy
|
||
|
# of this software and associated documentation files (the "Software"), to deal
|
||
|
# in the Software without restriction, including without limitation the rights
|
||
|
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||
|
# copies of the Software, and to permit persons to whom the Software is
|
||
|
# furnished to do so, subject to the following conditions:
|
||
|
#
|
||
|
# The above copyright notice and this permission notice shall be included in
|
||
|
# all copies or substantial portions of the Software.
|
||
|
#
|
||
|
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
|
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||
|
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||
|
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||
|
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||
|
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||
|
# THE SOFTWARE.
|
||
|
#
|
||
|
###############################################################################
|
||
|
|
||
|
|
||
|
try:
|
||
|
# use Cython implementation of XorMasker validator if available
|
||
|
|
||
|
from wsaccel.xormask import XorMaskerNull
|
||
|
# noinspection PyUnresolvedReferences
|
||
|
from wsaccel.xormask import createXorMasker
|
||
|
create_xor_masker = createXorMasker
|
||
|
|
||
|
except ImportError:
|
||
|
|
||
|
# fallback to pure Python implementation (this is faster on PyPy than above!)
|
||
|
|
||
|
# http://stackoverflow.com/questions/15014310/python3-xrange-lack-hurts
|
||
|
try:
|
||
|
# noinspection PyUnresolvedReferences
|
||
|
xrange
|
||
|
except NameError:
|
||
|
# Python 3
|
||
|
# noinspection PyShadowingBuiltins
|
||
|
xrange = range
|
||
|
|
||
|
from array import array
|
||
|
|
||
|
class XorMaskerNull(object):
|
||
|
|
||
|
__slots__ = ('_ptr',)
|
||
|
|
||
|
# noinspection PyUnusedLocal
|
||
|
def __init__(self, mask=None):
|
||
|
self._ptr = 0
|
||
|
|
||
|
def pointer(self):
|
||
|
return self._ptr
|
||
|
|
||
|
def reset(self):
|
||
|
self._ptr = 0
|
||
|
|
||
|
def process(self, data):
|
||
|
self._ptr += len(data)
|
||
|
return data
|
||
|
|
||
|
class XorMaskerSimple(object):
|
||
|
|
||
|
__slots__ = ('_ptr', '_msk')
|
||
|
|
||
|
def __init__(self, mask):
|
||
|
assert len(mask) == 4
|
||
|
self._ptr = 0
|
||
|
self._msk = array('B', mask)
|
||
|
|
||
|
def pointer(self):
|
||
|
return self._ptr
|
||
|
|
||
|
def reset(self):
|
||
|
self._ptr = 0
|
||
|
|
||
|
def process(self, data):
|
||
|
dlen = len(data)
|
||
|
payload = array('B', data)
|
||
|
for k in xrange(dlen):
|
||
|
payload[k] ^= self._msk[self._ptr & 3]
|
||
|
self._ptr += 1
|
||
|
return payload.tobytes()
|
||
|
|
||
|
class XorMaskerShifted1(object):
|
||
|
|
||
|
__slots__ = ('_ptr', '_mskarray')
|
||
|
|
||
|
def __init__(self, mask):
|
||
|
assert len(mask) == 4
|
||
|
self._ptr = 0
|
||
|
self._mskarray = [array('B'), array('B'), array('B'), array('B')]
|
||
|
for j in xrange(4):
|
||
|
self._mskarray[0].append(mask[j & 3])
|
||
|
self._mskarray[1].append(mask[(j + 1) & 3])
|
||
|
self._mskarray[2].append(mask[(j + 2) & 3])
|
||
|
self._mskarray[3].append(mask[(j + 3) & 3])
|
||
|
|
||
|
def pointer(self):
|
||
|
return self._ptr
|
||
|
|
||
|
def reset(self):
|
||
|
self._ptr = 0
|
||
|
|
||
|
def process(self, data):
|
||
|
dlen = len(data)
|
||
|
payload = array('B', data)
|
||
|
msk = self._mskarray[self._ptr & 3]
|
||
|
for k in xrange(dlen):
|
||
|
payload[k] ^= msk[k & 3]
|
||
|
self._ptr += dlen
|
||
|
return payload.tobytes()
|
||
|
|
||
|
def create_xor_masker(mask, length=None):
|
||
|
if length is None or length < 128:
|
||
|
return XorMaskerSimple(mask)
|
||
|
else:
|
||
|
return XorMaskerShifted1(mask)
|