128
 
‚    #
#  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:
  "   ˆl–äY>”Ê_)únàZ¸ÛjbÑ¿Âƒm—_ÁÀ     # Copyright (C) 2012 Canonical Ltd.
# Copyright (C) 2012 Hewlett-Packard Development Company, L.P.
# Copyright (C) 2012 Yahoo! Inc.
#
# Author: Scott Moser <scott.moser@canonical.com>
# Author: Juerg Haefliger <juerg.haefliger@hp.com>
# Author: Joshua Harlow <harlowja@yahoo-inc.com>
#
# This file is part of cloud-init. See LICENSE file for license information.

import jsonpatch

from cloudinit import handlers
from cloudinit import log as logging
from cloudinit import mergers
from cloudinit import util
from cloudinit import safeyaml

from cloudinit.settings import (PER_ALWAYS)

LOG = logging.getLogger(__name__)

MERGE_HEADER = 'Merge-Type'

# Due to the way the loading of yaml configuration was done previously,
# where previously each cloud config part was appended to a larger yaml
# file and then finally that file was loaded as one big yaml file we need
# to mimic that behavior by altering the default strategy to be replacing
# keys of prior merges.
#
#
# For example
# #file 1
# a: 3
# #file 2
# a: 22
# #combined file (comments not included)
# a: 3
# a: 22
#
# This gets loaded into yaml with final result {'a': 22}
DEF_MERGERS = mergers.string_extract_mergers('dict(replace)+list()+str()')
CLOUD_PREFIX = "#cloud-config"
JSONP_PREFIX = "#cloud-config-jsonp"


class CloudConfigPartHandler(handlers.Handler):

    # The conte