| Index: Tools/Scripts/webkitpy/thirdparty/webpagereplay/third_party/dns/entropy.py
|
| diff --git a/Tools/Scripts/webkitpy/thirdparty/webpagereplay/third_party/dns/entropy.py b/Tools/Scripts/webkitpy/thirdparty/webpagereplay/third_party/dns/entropy.py
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..fd9d4f8cdf8ce5e1f5cc122e3dda67ef6cc2245b
|
| --- /dev/null
|
| +++ b/Tools/Scripts/webkitpy/thirdparty/webpagereplay/third_party/dns/entropy.py
|
| @@ -0,0 +1,123 @@
|
| +# Copyright (C) 2009 Nominum, Inc.
|
| +#
|
| +# Permission to use, copy, modify, and distribute this software and its
|
| +# documentation for any purpose with or without fee is hereby granted,
|
| +# provided that the above copyright notice and this permission notice
|
| +# appear in all copies.
|
| +#
|
| +# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
|
| +# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
| +# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
|
| +# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
| +# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
| +# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
|
| +# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
| +
|
| +import os
|
| +import time
|
| +try:
|
| + import threading as _threading
|
| +except ImportError:
|
| + import dummy_threading as _threading
|
| +
|
| +class EntropyPool(object):
|
| + def __init__(self, seed=None):
|
| + self.pool_index = 0
|
| + self.digest = None
|
| + self.next_byte = 0
|
| + self.lock = _threading.Lock()
|
| + try:
|
| + import hashlib
|
| + self.hash = hashlib.sha1()
|
| + self.hash_len = 20
|
| + except:
|
| + try:
|
| + import sha
|
| + self.hash = sha.new()
|
| + self.hash_len = 20
|
| + except:
|
| + import md5
|
| + self.hash = md5.new()
|
| + self.hash_len = 16
|
| + self.pool = '\0' * self.hash_len
|
| + if not seed is None:
|
| + self.stir(seed)
|
| + self.seeded = True
|
| + else:
|
| + self.seeded = False
|
| +
|
| + def stir(self, entropy, already_locked=False):
|
| + if not already_locked:
|
| + self.lock.acquire()
|
| + try:
|
| + bytes = [ord(c) for c in self.pool]
|
| + for c in entropy:
|
| + if self.pool_index == self.hash_len:
|
| + self.pool_index = 0
|
| + b = ord(c) & 0xff
|
| + bytes[self.pool_index] ^= b
|
| + self.pool_index += 1
|
| + self.pool = ''.join([chr(c) for c in bytes])
|
| + finally:
|
| + if not already_locked:
|
| + self.lock.release()
|
| +
|
| + def _maybe_seed(self):
|
| + if not self.seeded:
|
| + try:
|
| + seed = os.urandom(16)
|
| + except:
|
| + try:
|
| + r = file('/dev/urandom', 'r', 0)
|
| + try:
|
| + seed = r.read(16)
|
| + finally:
|
| + r.close()
|
| + except:
|
| + seed = str(time.time())
|
| + self.seeded = True
|
| + self.stir(seed, True)
|
| +
|
| + def random_8(self):
|
| + self.lock.acquire()
|
| + self._maybe_seed()
|
| + try:
|
| + if self.digest is None or self.next_byte == self.hash_len:
|
| + self.hash.update(self.pool)
|
| + self.digest = self.hash.digest()
|
| + self.stir(self.digest, True)
|
| + self.next_byte = 0
|
| + value = ord(self.digest[self.next_byte])
|
| + self.next_byte += 1
|
| + finally:
|
| + self.lock.release()
|
| + return value
|
| +
|
| + def random_16(self):
|
| + return self.random_8() * 256 + self.random_8()
|
| +
|
| + def random_32(self):
|
| + return self.random_16() * 65536 + self.random_16()
|
| +
|
| + def random_between(self, first, last):
|
| + size = last - first + 1
|
| + if size > 4294967296L:
|
| + raise ValueError('too big')
|
| + if size > 65536:
|
| + rand = self.random_32
|
| + max = 4294967295L
|
| + elif size > 256:
|
| + rand = self.random_16
|
| + max = 65535
|
| + else:
|
| + rand = self.random_8
|
| + max = 255
|
| + return (first + size * rand() // (max + 1))
|
| +
|
| +pool = EntropyPool()
|
| +
|
| +def random_16():
|
| + return pool.random_16()
|
| +
|
| +def between(first, last):
|
| + return pool.random_between(first, last)
|
|
|