From 58dce62706aa72a34e76cd4ca668b633ff9e395c Mon Sep 17 00:00:00 2001
From: ChaoticByte <contact@chaoticbyte.net>
Date: Mon, 24 Jun 2024 16:55:30 +0200
Subject: [PATCH] Add project files

---
 LICENSE         |  2 +-
 obf/__init__.py | 45 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+), 1 deletion(-)
 create mode 100644 obf/__init__.py

diff --git a/LICENSE b/LICENSE
index c06137c..920dc4f 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2024 Julian Müller
+Copyright (c) 2024 Julian Müller (ChaoticByte)
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/obf/__init__.py b/obf/__init__.py
new file mode 100644
index 0000000..03add9a
--- /dev/null
+++ b/obf/__init__.py
@@ -0,0 +1,45 @@
+# Copyright (c) 2024 Julian Müller (ChaoticByte)
+# License: MIT
+
+def obf(data: bytes, key: bytes, decrypt: bool = False, iterations: int = 64) -> bytes:
+    assert type(data) == bytes
+    assert type(key) == bytes
+    assert type(iterations) == int
+    assert type(decrypt) == bool
+    data = bytearray(data)
+    key = bytearray(key)
+    len_data = len(data)
+    len_key = len(key)
+    def a(d):
+        # shift (encrypt)
+        if not decrypt:
+            for i in range(len_data):
+                n = key[i % len_key]
+                d[i] = (d[i] + n) % 256
+        # transpose
+        swap_indices = [] # list of tuples that stores transposition data (from, to)
+        k = 0
+        for i in range(len_data):
+            k += i + key[i % len_key] # we add to k
+            j = k % len_data          # and use it to make cryptanalysis harder (I think?)
+            swap_indices.append((i, j)) # store transposition data
+        if decrypt:
+            swap_indices.reverse()
+        for a, b in swap_indices:
+            # swap values
+            a_ = d[a]
+            b_ = d[b]
+            d[a] = b_
+            d[b] = a_
+        # unshift (decrypt)
+        if decrypt:
+            for i in range(len_data):
+                n = key[i % len_key]
+                b = d[i] - n
+                while b < 0:
+                    b = 256 + b
+                d[i] = b
+        return d
+    for i in range(iterations):
+        data = a(data)
+    return bytes(data)