| Index: third_party/google-endpoints/Crypto/Random/OSRNG/nt.py
|
| diff --git a/third_party/google-endpoints/Crypto/Random/OSRNG/nt.py b/third_party/google-endpoints/Crypto/Random/OSRNG/nt.py
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..c1c2f44e642d03942583d491c4c6b3bcc5ee07c1
|
| --- /dev/null
|
| +++ b/third_party/google-endpoints/Crypto/Random/OSRNG/nt.py
|
| @@ -0,0 +1,74 @@
|
| +#
|
| +# Random/OSRNG/nt.py : OS entropy source for MS Windows
|
| +#
|
| +# Written in 2008 by Dwayne C. Litzenberger <dlitz@dlitz.net>
|
| +#
|
| +# ===================================================================
|
| +# The contents of this file are dedicated to the public domain. To
|
| +# the extent that dedication to the public domain is not available,
|
| +# everyone is granted a worldwide, perpetual, royalty-free,
|
| +# non-exclusive license to exercise all rights associated with the
|
| +# contents of this file for any purpose whatsoever.
|
| +# No rights are reserved.
|
| +#
|
| +# 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.
|
| +# ===================================================================
|
| +
|
| +
|
| +__revision__ = "$Id$"
|
| +__all__ = ['WindowsRNG']
|
| +
|
| +import winrandom
|
| +from rng_base import BaseRNG
|
| +
|
| +class WindowsRNG(BaseRNG):
|
| +
|
| + name = "<CryptGenRandom>"
|
| +
|
| + def __init__(self):
|
| + self.__winrand = winrandom.new()
|
| + BaseRNG.__init__(self)
|
| +
|
| + def flush(self):
|
| + """Work around weakness in Windows RNG.
|
| +
|
| + The CryptGenRandom mechanism in some versions of Windows allows an
|
| + attacker to learn 128 KiB of past and future output. As a workaround,
|
| + this function reads 128 KiB of 'random' data from Windows and discards
|
| + it.
|
| +
|
| + For more information about the weaknesses in CryptGenRandom, see
|
| + _Cryptanalysis of the Random Number Generator of the Windows Operating
|
| + System_, by Leo Dorrendorf and Zvi Gutterman and Benny Pinkas
|
| + http://eprint.iacr.org/2007/419
|
| + """
|
| + if self.closed:
|
| + raise ValueError("I/O operation on closed file")
|
| + data = self.__winrand.get_bytes(128*1024)
|
| + assert (len(data) == 128*1024)
|
| + BaseRNG.flush(self)
|
| +
|
| + def _close(self):
|
| + self.__winrand = None
|
| +
|
| + def _read(self, N):
|
| + # Unfortunately, research shows that CryptGenRandom doesn't provide
|
| + # forward secrecy and fails the next-bit test unless we apply a
|
| + # workaround, which we do here. See http://eprint.iacr.org/2007/419
|
| + # for information on the vulnerability.
|
| + self.flush()
|
| + data = self.__winrand.get_bytes(N)
|
| + self.flush()
|
| + return data
|
| +
|
| +def new(*args, **kwargs):
|
| + return WindowsRNG(*args, **kwargs)
|
| +
|
| +# vim:set ts=4 sw=4 sts=4 expandtab:
|
|
|