1 files changed, 47 insertions, 0 deletions
diff --git a/src/ssh_audit/ssh1_crc32.py b/src/ssh_audit/ssh1_crc32.py
new file mode 100644
index 0000000..55089ed
--- /dev/null
+++ b/src/ssh_audit/ssh1_crc32.py
@@ -0,0 +1,47 @@
+"""
+   The MIT License (MIT)
+
+   Copyright (C) 2017 Andris Raugulis (moo@arthepsy.eu)
+
+   Permission is hereby granted, free of charge, to any person obtaining a copy
+   of this software and associated documentation files (the "Software"), to deal
+   in the Software without restriction, including without limitation the rights
+   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+   copies of the Software, and to permit persons to whom the Software is
+   furnished to do so, subject to the following conditions:
+
+   The above copyright notice and this permission notice shall be included in
+   all copies or substantial portions of the Software.
+
+   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.
+"""
+# pylint: disable=unused-import
+from typing import Dict, List, Set, Sequence, Tuple, Iterable  # noqa: F401
+from typing import Callable, Optional, Union, Any  # noqa: F401
+
+
+class SSH1_CRC32:
+    def __init__(self) -> None:
+        self._table = [0] * 256
+        for i in range(256):
+            crc = 0
+            n = i
+            for _ in range(8):
+                x = (crc ^ n) & 1
+                crc = (crc >> 1) ^ (x * 0xedb88320)
+                n = n >> 1
+                self._table[i] = crc
+
+    def calc(self, v: bytes) -> int:
+        crc, length = 0, len(v)
+        for i in range(length):
+            n = ord(v[i:i + 1])
+            n = n ^ (crc & 0xff)
+            crc = (crc >> 8) ^ self._table[n]
+        return crc