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author | S. Solomon Darnell | 2025-03-28 21:52:21 -0500 |
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committer | S. Solomon Darnell | 2025-03-28 21:52:21 -0500 |
commit | 4a52a71956a8d46fcb7294ac71734504bb09bcc2 (patch) | |
tree | ee3dc5af3b6313e921cd920906356f5d4febc4ed /.venv/lib/python3.12/site-packages/dns/entropy.py | |
parent | cc961e04ba734dd72309fb548a2f97d67d578813 (diff) | |
download | gn-ai-master.tar.gz |
Diffstat (limited to '.venv/lib/python3.12/site-packages/dns/entropy.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/dns/entropy.py | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/dns/entropy.py b/.venv/lib/python3.12/site-packages/dns/entropy.py new file mode 100644 index 00000000..4dcdc627 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/dns/entropy.py @@ -0,0 +1,130 @@ +# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license + +# Copyright (C) 2009-2017 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 hashlib +import os +import random +import threading +import time +from typing import Any, Optional + + +class EntropyPool: + # This is an entropy pool for Python implementations that do not + # have a working SystemRandom. I'm not sure there are any, but + # leaving this code doesn't hurt anything as the library code + # is used if present. + + def __init__(self, seed: Optional[bytes] = None): + self.pool_index = 0 + self.digest: Optional[bytearray] = None + self.next_byte = 0 + self.lock = threading.Lock() + self.hash = hashlib.sha1() + self.hash_len = 20 + self.pool = bytearray(b"\0" * self.hash_len) + if seed is not None: + self._stir(seed) + self.seeded = True + self.seed_pid = os.getpid() + else: + self.seeded = False + self.seed_pid = 0 + + def _stir(self, entropy: bytes) -> None: + for c in entropy: + if self.pool_index == self.hash_len: + self.pool_index = 0 + b = c & 0xFF + self.pool[self.pool_index] ^= b + self.pool_index += 1 + + def stir(self, entropy: bytes) -> None: + with self.lock: + self._stir(entropy) + + def _maybe_seed(self) -> None: + if not self.seeded or self.seed_pid != os.getpid(): + try: + seed = os.urandom(16) + except Exception: # pragma: no cover + try: + with open("/dev/urandom", "rb", 0) as r: + seed = r.read(16) + except Exception: + seed = str(time.time()).encode() + self.seeded = True + self.seed_pid = os.getpid() + self.digest = None + seed = bytearray(seed) + self._stir(seed) + + def random_8(self) -> int: + with self.lock: + self._maybe_seed() + if self.digest is None or self.next_byte == self.hash_len: + self.hash.update(bytes(self.pool)) + self.digest = bytearray(self.hash.digest()) + self._stir(self.digest) + self.next_byte = 0 + value = self.digest[self.next_byte] + self.next_byte += 1 + return value + + def random_16(self) -> int: + return self.random_8() * 256 + self.random_8() + + def random_32(self) -> int: + return self.random_16() * 65536 + self.random_16() + + def random_between(self, first: int, last: int) -> int: + size = last - first + 1 + if size > 4294967296: + raise ValueError("too big") + if size > 65536: + rand = self.random_32 + max = 4294967295 + elif size > 256: + rand = self.random_16 + max = 65535 + else: + rand = self.random_8 + max = 255 + return first + size * rand() // (max + 1) + + +pool = EntropyPool() + +system_random: Optional[Any] +try: + system_random = random.SystemRandom() +except Exception: # pragma: no cover + system_random = None + + +def random_16() -> int: + if system_random is not None: + return system_random.randrange(0, 65536) + else: + return pool.random_16() + + +def between(first: int, last: int) -> int: + if system_random is not None: + return system_random.randrange(first, last + 1) + else: + return pool.random_between(first, last) |