Lol

venv/lib/python3.11/site-packages/cryptography/hazmat/primitives/kdf/scrypt.py

@@ -0,0 +1,80 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import annotations
+
+import sys
+import typing
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized,
+    InvalidKey,
+    UnsupportedAlgorithm,
+)
+from cryptography.hazmat.bindings._rust import openssl as rust_openssl
+from cryptography.hazmat.primitives import constant_time
+from cryptography.hazmat.primitives.kdf import KeyDerivationFunction
+
+# This is used by the scrypt tests to skip tests that require more memory
+# than the MEM_LIMIT
+_MEM_LIMIT = sys.maxsize // 2
+
+
+class Scrypt(KeyDerivationFunction):
+    def __init__(
+        self,
+        salt: bytes,
+        length: int,
+        n: int,
+        r: int,
+        p: int,
+        backend: typing.Any = None,
+    ):
+        from cryptography.hazmat.backends.openssl.backend import (
+            backend as ossl,
+        )
+
+        if not ossl.scrypt_supported():
+            raise UnsupportedAlgorithm(
+                "This version of OpenSSL does not support scrypt"
+            )
+        self._length = length
+        utils._check_bytes("salt", salt)
+        if n < 2 or (n & (n - 1)) != 0:
+            raise ValueError("n must be greater than 1 and be a power of 2.")
+
+        if r < 1:
+            raise ValueError("r must be greater than or equal to 1.")
+
+        if p < 1:
+            raise ValueError("p must be greater than or equal to 1.")
+
+        self._used = False
+        self._salt = salt
+        self._n = n
+        self._r = r
+        self._p = p
+
+    def derive(self, key_material: bytes) -> bytes:
+        if self._used:
+            raise AlreadyFinalized("Scrypt instances can only be used once.")
+        self._used = True
+
+        utils._check_byteslike("key_material", key_material)
+
+        return rust_openssl.kdf.derive_scrypt(
+            key_material,
+            self._salt,
+            self._n,
+            self._r,
+            self._p,
+            _MEM_LIMIT,
+            self._length,
+        )
+
+    def verify(self, key_material: bytes, expected_key: bytes) -> None:
+        derived_key = self.derive(key_material)
+        if not constant_time.bytes_eq(derived_key, expected_key):
+            raise InvalidKey("Keys do not match.")