From 77b90fdf4dd3cc3f7a4c6deaec04b29122eb9b1a Mon Sep 17 00:00:00 2001
From: Roman Babenko <babenek@gmail.com>
Date: Sun, 10 Nov 2024 12:00:02 +0200
Subject: [PATCH] etc

---
 base64magic.py    | 56 +++++++++++++++++++++++++++++++++++++
 crc32file.py      | 30 ++++++++++++++++++++
 gnutar.py         | 30 ++++++++++++++++++++
 perf_enumerate.py | 71 +++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 187 insertions(+)
 create mode 100644 base64magic.py
 create mode 100644 crc32file.py
 create mode 100644 gnutar.py
 create mode 100644 perf_enumerate.py

diff --git a/base64magic.py b/base64magic.py
new file mode 100644
index 0000000..114e7ce
--- /dev/null
+++ b/base64magic.py
@@ -0,0 +1,56 @@
+import base64
+import re
+import string
+import struct
+import unittest
+
+
+def gen_encoded(size, text=''):
+    size -= 1
+    if 0 <= size:
+        for x in string.digits + string.ascii_letters:
+            yield from gen_encoded(size, text + x)
+    else:
+        yield text
+
+
+def check_asc_or_desc(line_data_value: str) -> bool:
+    """ValuePatternCheck as example"""
+    count_asc = 1
+    count_desc = 1
+    for i in range(len(line_data_value) - 1):
+        if line_data_value[i] in string.ascii_letters + string.digits \
+                and ord(line_data_value[i + 1]) - ord(line_data_value[i]) == 1:
+            count_asc += 1
+            if 4 == count_asc:
+                return True
+        else:
+            count_asc = 1
+        if line_data_value[i] in string.ascii_letters + string.digits \
+                and ord(line_data_value[i]) - ord(line_data_value[i + 1]) == 1:
+            count_desc += 1
+            if 4 == count_desc:
+                return True
+        else:
+            count_desc = 1
+            continue
+    return False
+
+
+def main():
+    pattern_similar = re.compile(r"(\w)\1{3,}")
+    counter = 0
+    for x in gen_encoded(4):
+        v="pA5s"+x
+        if pattern_similar.findall(v) or check_asc_or_desc(v):
+            continue
+        outer = sum(ord(i) for i in v)
+        data = base64.b64decode(v)
+        inner1, inner2, inner3 = struct.unpack("<HHH", data)
+        if inner2 ^ outer == inner1 ^ inner3:
+            counter += 1
+            print(counter, v)
+
+
+if """__main__""" == __name__:
+    main()
diff --git a/crc32file.py b/crc32file.py
new file mode 100644
index 0000000..351a9ae
--- /dev/null
+++ b/crc32file.py
@@ -0,0 +1,30 @@
+import binascii
+
+import multiprocessing
+
+
+def run(inpt):
+    for i in range(inpt[1] << 28, inpt[1] << 28 + 0x10000000):
+        aug = f"{i:08x}".encode()
+        data = aug + inpt[0]
+        crc32 = binascii.crc32(data)
+        if 0 == crc32:
+            print(data)
+            break
+        if 0 == i & 0xFFFFFF:
+            print(f"{i:08x}", aug)
+    else:
+        print("nope")
+
+
+def main():
+    with open(__file__, 'rb') as f:
+        text = f.read()
+    inpt = [(text, x) for x in range(16)]
+    with multiprocessing.Pool(16) as p:
+        for _ in p.map(run, inpt):
+            pass
+
+
+if __name__ == '__main__':
+    main()
diff --git a/gnutar.py b/gnutar.py
new file mode 100644
index 0000000..1e3723d
--- /dev/null
+++ b/gnutar.py
@@ -0,0 +1,30 @@
+import io
+import tarfile
+
+
+def main(filename):
+    data = bytearray()
+    with open(filename, 'rb') as f:
+        data = f.read()
+
+    with tarfile.TarFile(fileobj=io.BytesIO(data)) as tf:
+        for tfi in tf.getmembers():
+            # skip directory
+            if not tfi.isreg():
+                continue
+            if tfi.size > 1 << 30:
+                print("Quota reached")
+                continue
+            with tf.extractfile(tfi) as f:
+                f_seek = f.seek(io.SEEK_END)
+                f_tell = f.tell()
+                if f_tell > 1 << 30:
+                    print("Quota reached")
+                    continue
+                f.seek(io.SEEK_SET)
+                d = f.read()
+                print(len(d))
+
+
+if __name__ == """__main__""":
+    main("gnu-sparse-big.tar")
diff --git a/perf_enumerate.py b/perf_enumerate.py
new file mode 100644
index 0000000..57e48f9
--- /dev/null
+++ b/perf_enumerate.py
@@ -0,0 +1,71 @@
+"""
+MIT License
+
+Copyright (c) 2024 Roman Babenko
+
+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.
+"""
+import statistics
+import sys
+import time
+from typing import List
+
+LEN = 100
+SIZE = 10000
+
+
+def perf_enum_list(args):
+    x = args[0]
+    for i in range(SIZE):
+        for n, i in x:
+            assert str(n) == i
+
+
+def perf_plain_list(args):
+    x = args[0]
+    for i in range(SIZE):
+        for n, i in enumerate(x):
+            assert str(n) == i
+
+
+def perf_test(func, data):
+    stat: List[float] = []
+    for n in range(LEN):
+        start_time = time.time()
+        func(data)
+        stat.append(time.time() - start_time)
+    print(f"{func} Average = {statistics.mean(stat)} Deviation = {statistics.stdev(stat)}")
+
+
+def main() -> int:
+    start_time = time.time()
+    l = [str(x) for x in range(10)]
+    n = enumerate(l)
+    perf_test(perf_enum_list, (n,))
+    perf_test(perf_plain_list, (l,))
+    print(f"Total time: {time.time() - start_time} SIZE={SIZE}")
+    return 0
+
+
+# <function perf_enum_list at 0x7076afd33d90> Average = 0.00018164873123168945 Deviation = 1.3166524916387962e-05
+# <function perf_plain_list at 0x7076af15bf40> Average = 0.008094820976257324 Deviation = 0.0003013285439674138
+# Total time: 0.8281574249267578 SIZE=10000
+
+if __name__ == "__main__":
+    sys.exit(main())