added all ctfs

ForeverCTF/xor/decrypt_binary.py

@@ -0,0 +1,9 @@
+import sys
+
+binary = bytearray(open(sys.argv[1], 'rb').read())
+size = len(binary)
+
+for i in range (size):
+    binary[i] = binary[i] ^ 0x41
+
+open(sys.argv[2], 'wb').write(binary)