fix transmuting to pointer types UB

closes #141

Cargo.lock

@@ -1292,6 +1292,7 @@ dependencies = [
  "async-trait",
  "clap",
  "core-graphics",
+ "endi",
  "env_logger",
  "futures",
  "futures-core",

Cargo.toml

@@ -35,6 +35,7 @@ once_cell = "1.19.0"
 num_enum = "0.7.2"
 hostname = "0.4.0"
 slab = "0.4.9"
+endi = "1.1.0"
 
 [target.'cfg(unix)'.dependencies]
 libc = "0.2.148"

README.md

@@ -69,7 +69,15 @@ Precompiled release binaries for Windows, MacOS and Linux are available in the [
 For Windows, the depenedencies are included in the .zip file, for other operating systems see [Installing Dependencies](#installing-dependencies).
 
 ### Arch Linux
-Lan Mouse is available on the AUR:
+
+Lan Mouse can be installed from the [official repositories](https://archlinux.org/packages/extra/x86_64/lan-mouse/):
+
+```sh
+pacman -S lan-mouse
+```
+
+It is also available on the AUR:
+
 ```sh
 # git version (includes latest changes)
 paru -S lan-mouse-git

flake.lock

@@ -20,11 +20,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1710806803,
+        "lastModified": 1716293225,
-        "narHash": "sha256-qrxvLS888pNJFwJdK+hf1wpRCSQcqA6W5+Ox202NDa0=",
+        "narHash": "sha256-pU9ViBVE3XYb70xZx+jK6SEVphvt7xMTbm6yDIF4xPs=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "b06025f1533a1e07b6db3e75151caa155d1c7eb3",
+        "rev": "3eaeaeb6b1e08a016380c279f8846e0bd8808916",
         "type": "github"
       },
       "original": {
@@ -48,11 +48,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1710987136,
+        "lastModified": 1716257780,
-        "narHash": "sha256-Q8GRdlAIKZ8tJUXrbcRO1pA33AdoPfTUirsSnmGQnOU=",
+        "narHash": "sha256-R+NjvJzKEkTVCmdrKRfPE4liX/KMGVqGUwwS5H8ET8A=",
         "owner": "oxalica",
         "repo": "rust-overlay",
-        "rev": "97596b54ac34ad8184ca1eef44b1ec2e5c2b5f9e",
+        "rev": "4e5e3d2c5c9b2721bd266f9e43c14e96811b89d2",
         "type": "github"
       },
       "original": {

nix/default.nix

@@ -2,10 +2,14 @@
   rustPlatform,
   lib,
   pkgs,
-}:
+}: let
+  cargoToml = builtins.fromTOML (builtins.readFile ../Cargo.toml);
+  pname = cargoToml.package.name;
+  version = cargoToml.package.version;
+in
 rustPlatform.buildRustPackage {
-  pname = "lan-mouse";
+  pname = pname;
-  version = "0.7.0";
+  version = version;
 
   nativeBuildInputs = with pkgs; [
     pkg-config
@@ -23,7 +27,7 @@ rustPlatform.buildRustPackage {
   ];
 
   src = builtins.path {
-    name = "lan-mouse";
+    name = pname;
     path = lib.cleanSource ../.;
   };
 
@@ -38,7 +42,7 @@ rustPlatform.buildRustPackage {
       Lan Mouse is a mouse and keyboard sharing software similar to universal-control on Apple devices. It allows for using multiple pcs with a single set of mouse and keyboard. This is also known as a Software KVM switch.
       The primary target is Wayland on Linux but Windows and MacOS and Linux on Xorg have partial support as well (see below for more details).
     '';
-    mainProgram = "lan-mouse";
+    mainProgram = pname;
     platforms = platforms.all;
   };
 }

src/capture/windows.rs

@@ -96,8 +96,7 @@ unsafe fn get_event_tid() -> Option<u32> {
 static mut ENTRY_POINT: (i32, i32) = (0, 0);
 
 fn to_mouse_event(wparam: WPARAM, lparam: LPARAM) -> Option<PointerEvent> {
-    let mouse_low_level: MSLLHOOKSTRUCT =
+    let mouse_low_level: MSLLHOOKSTRUCT = unsafe { *(lparam.0 as *const MSLLHOOKSTRUCT) };
-        unsafe { *std::mem::transmute::<LPARAM, *const MSLLHOOKSTRUCT>(lparam) };
     match wparam {
         WPARAM(p) if p == WM_LBUTTONDOWN as usize => Some(PointerEvent::Button {
             time: 0,
@@ -167,8 +166,7 @@ fn to_mouse_event(wparam: WPARAM, lparam: LPARAM) -> Option<PointerEvent> {
 }
 
 unsafe fn to_key_event(wparam: WPARAM, lparam: LPARAM) -> Option<KeyboardEvent> {
-    let kybrdllhookstruct: KBDLLHOOKSTRUCT =
+    let kybrdllhookstruct: KBDLLHOOKSTRUCT = *(lparam.0 as *const KBDLLHOOKSTRUCT);
-        *std::mem::transmute::<LPARAM, *const KBDLLHOOKSTRUCT>(lparam);
     let mut scan_code = kybrdllhookstruct.scanCode;
     log::trace!("scan_code: {scan_code}");
     if kybrdllhookstruct.flags.contains(LLKHF_EXTENDED) {
@@ -247,8 +245,7 @@ unsafe fn check_client_activation(wparam: WPARAM, lparam: LPARAM) -> bool {
     if wparam.0 != WM_MOUSEMOVE as usize {
         return ACTIVE_CLIENT.is_some();
     }
-    let mouse_low_level: MSLLHOOKSTRUCT =
+    let mouse_low_level: MSLLHOOKSTRUCT = *(lparam.0 as *const MSLLHOOKSTRUCT);
-        unsafe { *std::mem::transmute::<LPARAM, *const MSLLHOOKSTRUCT>(lparam) };
     static mut PREV_POS: Option<(i32, i32)> = None;
     let curr_pos = (mouse_low_level.pt.x, mouse_low_level.pt.y);
     let prev_pos = PREV_POS.unwrap_or(curr_pos);

src/frontend/gtk.rs

@@ -11,6 +11,7 @@ use std::{
 use crate::frontend::{gtk::window::Window, FrontendRequest};
 
 use adw::Application;
+use endi::{Endian, ReadBytes};
 use gtk::{
     gdk::Display, glib::clone, prelude::*, subclass::prelude::ObjectSubclassIsExt, IconTheme,
 };
@@ -85,16 +86,14 @@ fn build_ui(app: &Application) {
     gio::spawn_blocking(move || {
         match loop {
             // read length
-            let mut len = [0u8; 8];
+            let len = match rx.read_u64(Endian::Big) {
-            match rx.read_exact(&mut len) {
+                Ok(l) => l,
-                Ok(_) => (),
                 Err(e) if e.kind() == ErrorKind::UnexpectedEof => break Ok(()),
                 Err(e) => break Err(e),
             };
-            let len = usize::from_be_bytes(len);
 
             // read payload
-            let mut buf = vec![0u8; len];
+            let mut buf = vec![0u8; len as usize];
             match rx.read_exact(&mut buf) {
                 Ok(_) => (),
                 Err(e) if e.kind() == ErrorKind::UnexpectedEof => break Ok(()),

src/frontend/gtk/window.rs

@@ -10,6 +10,7 @@ use std::net::TcpStream;
 
 use adw::prelude::*;
 use adw::subclass::prelude::*;
+use endi::{Endian, WriteBytes};
 use glib::{clone, Object};
 use gtk::{
     gio,
@@ -265,8 +266,7 @@ impl Window {
         let mut stream = self.imp().stream.borrow_mut();
         let stream = stream.as_mut().unwrap();
         let bytes = json.as_bytes();
-        let len = bytes.len().to_be_bytes();
+        if let Err(e) = stream.write_u64(Endian::Big, bytes.len() as u64) {
-        if let Err(e) = stream.write(&len) {
             log::error!("error sending message: {e}");
         };
         if let Err(e) = stream.write(bytes) {