Add native Linux controls and tray menu for BTD 700

tools/extract_control_assembly.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python3
+"""Extract only the application assembly from a locally supplied .NET bundle.
+
+No downloading or execution of the original application. Output remains private
+analysis material; it is not needed at runtime and must not be distributed here.
+"""
+import argparse
+import io
+from pathlib import Path
+import struct
+import zlib
+
+parser = argparse.ArgumentParser(description=__doc__)
+parser.add_argument('exe', type=Path)
+parser.add_argument('output', type=Path, help='Output DLL path, outside this project')
+args = parser.parse_args()
+data = args.exe.read_bytes()
+signature = bytes.fromhex('8b1202b96a612038727b930214d7a03213f5b9e6efae3318ee3b2dce24b36aae')
+position = data.find(signature)
+if position < 8:
+    parser.error('No .NET bundle signature found')
+offset = struct.unpack_from('<q', data, position - 8)[0]
+if not 0 <= offset < len(data):
+    parser.error('Invalid manifest offset')
+stream = io.BytesIO(data)
+stream.seek(offset)
+
+
+def unpack(fmt):
+    return struct.unpack(fmt, stream.read(struct.calcsize(fmt)))
+
+
+def read_string():
+    length = 0
+    for shift in range(0, 35, 7):
+        value = unpack('<B')[0]
+        length |= (value & 127) << shift
+        if not value & 128:
+            if length > 4096:
+                raise ValueError('Unexpected string length')
+            return stream.read(length).decode('utf-8')
+    raise ValueError('Invalid string prefix')
+
+
+major, minor, count = unpack('<IIi')
+if major != 6 or not 1 <= count <= 10000:
+    parser.error('Expected a version-6 .NET bundle')
+read_string()
+stream.read(40)
+for _ in range(count):
+    offset, size, compressed, kind = unpack('<qqqB')
+    name = read_string()
+    if name != 'Sennheiser Dongle Control.dll':
+        continue
+    length = compressed or size
+    if not 0 <= offset <= offset + length <= len(data) or not 0 < size < 32 * 1024 * 1024:
+        parser.error('Invalid assembly bounds')
+    blob = data[offset:offset + length]
+    if compressed:
+        decoder = zlib.decompressobj(-15)
+        blob = decoder.decompress(blob, size + 1)
+    if len(blob) != size or not blob.startswith(b'MZ'):
+        parser.error('Assembly size or signature mismatch')
+    with args.output.open('xb') as output:
+        output.write(blob)
+    print(f'Extracted {name}: {len(blob)} bytes to {args.output}')
+    break
+else:
+    parser.error('Application assembly not found')