Move MTU helpers to talpid-net crate

8 files changed, 41 insertions, 3 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 6c25a0ade8..f9fa547879 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3946,6 +3946,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "talpid-net"
+version = "0.0.0"
+dependencies = [
+ "libc",
+ "log",
+ "socket2",
+ "talpid-types",
+]
+
+[[package]]
 name = "talpid-openvpn"
 version = "0.0.0"
 dependencies = [
@@ -4128,6 +4138,7 @@ dependencies = [
  "socket2",
  "surge-ping",
  "talpid-dbus",
+ "talpid-net",
  "talpid-routing",
  "talpid-tunnel",
  "talpid-tunnel-config-client",
diff --git a/Cargo.toml b/Cargo.toml
index c3b1185cbb..1317951f65 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -28,6 +28,7 @@ members = [
     "talpid-core",
     "talpid-dbus",
     "talpid-future",
+    "talpid-net",
     "talpid-openvpn",
     "talpid-openvpn-plugin",
     "talpid-platform-metadata",
diff --git a/talpid-net/Cargo.toml b/talpid-net/Cargo.toml
new file mode 100644
index 0000000000..aa30ed1b5b
--- /dev/null
+++ b/talpid-net/Cargo.toml
@@ -0,0 +1,17 @@
+[package]
+name = "talpid-net"
+description = "Networking helpers"
+authors.workspace = true
+repository.workspace = true
+license.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+
+[lints]
+workspace = true
+
+[target.'cfg(unix)'.dependencies]
+libc = "0.2"
+talpid-types = { path = "../talpid-types" }
+socket2 = { version = "0.5.3", features = ["all"] }
+log = { workspace = true }
diff --git a/talpid-net/src/lib.rs b/talpid-net/src/lib.rs
new file mode 100644
index 0000000000..b13064bf70
--- /dev/null
+++ b/talpid-net/src/lib.rs
@@ -0,0 +1,2 @@
+#[cfg(unix)]
+pub mod unix;
diff --git a/talpid-wireguard/src/unix.rs b/talpid-net/src/unix.rs
index 1e58a696df..ef2bfdeb27 100644
--- a/talpid-wireguard/src/unix.rs
+++ b/talpid-net/src/unix.rs
@@ -1,3 +1,5 @@
+#![cfg(any(target_os = "linux", target_os = "macos"))]
+
 use std::{io, os::fd::AsRawFd};
 
 use socket2::Domain;
@@ -27,6 +29,7 @@ pub fn set_mtu(interface_name: &str, mtu: u16) -> Result<(), io::Error> {
         ));
     }
 
+    // SAFETY: `interface_name.len()` is less than `ifr.ifr_name.len()`
     unsafe {
         std::ptr::copy_nonoverlapping(
             interface_name.as_ptr() as *const libc::c_char,
@@ -36,6 +39,7 @@ pub fn set_mtu(interface_name: &str, mtu: u16) -> Result<(), io::Error> {
     };
     ifr.ifr_ifru.ifru_mtu = mtu as i32;
 
+    // SAFETY: SIOCSIFMTU expects an ifreq with an MTU and interface set
     if unsafe { libc::ioctl(sock.as_raw_fd(), SIOCSIFMTU, &ifr) } < 0 {
         let e = std::io::Error::last_os_error();
         log::error!("{}", e.display_chain_with_msg("SIOCSIFMTU failed"));
@@ -59,6 +63,7 @@ pub fn get_mtu(interface_name: &str) -> Result<u16, io::Error> {
         ));
     }
 
+    // SAFETY: `interface_name.len()` is less than `ifr.ifr_name.len()`
     unsafe {
         std::ptr::copy_nonoverlapping(
             interface_name.as_ptr() as *const libc::c_char,
@@ -67,6 +72,7 @@ pub fn get_mtu(interface_name: &str) -> Result<u16, io::Error> {
         )
     };
 
+    // SAFETY: SIOCGIFMTU expects an ifreq with an interface set
     if unsafe { libc::ioctl(sock.as_raw_fd(), SIOCGIFMTU, &ifr) } < 0 {
         let e = std::io::Error::last_os_error();
         log::error!("{}", e.display_chain_with_msg("SIOCGIFMTU failed"));
diff --git a/talpid-wireguard/Cargo.toml b/talpid-wireguard/Cargo.toml
index 806cdd1447..3fea8a17c0 100644
--- a/talpid-wireguard/Cargo.toml
+++ b/talpid-wireguard/Cargo.toml
@@ -45,6 +45,9 @@ tokio-stream = { version = "0.1", features = ["io-util"] }
 [target.'cfg(unix)'.dependencies]
 nix = "0.23"
 
+[target.'cfg(any(target_os = "linux", target_os = "macos"))'.dependencies]
+talpid-net = { path = "../talpid-net" }
+
 [target.'cfg(target_os = "linux")'.dependencies]
 rtnetlink = "0.11"
 netlink-packet-core = "0.4.2"
diff --git a/talpid-wireguard/src/lib.rs b/talpid-wireguard/src/lib.rs
index b9a85560ee..ca59e014ff 100644
--- a/talpid-wireguard/src/lib.rs
+++ b/talpid-wireguard/src/lib.rs
@@ -49,8 +49,6 @@ mod connectivity_check;
 mod logging;
 mod ping_monitor;
 mod stats;
-#[cfg(any(target_os = "linux", target_os = "macos"))]
-mod unix;
 #[cfg(wireguard_go)]
 mod wireguard_go;
 #[cfg(target_os = "linux")]
diff --git a/talpid-wireguard/src/mtu_detection.rs b/talpid-wireguard/src/mtu_detection.rs
index 5132705719..11c6625f2c 100644
--- a/talpid-wireguard/src/mtu_detection.rs
+++ b/talpid-wireguard/src/mtu_detection.rs
@@ -60,7 +60,7 @@ pub async fn automatic_mtu_correction(
         log::warn!("Lowering MTU from {} to {verified_mtu}", current_tunnel_mtu);
 
         #[cfg(any(target_os = "linux", target_os = "macos"))]
-        crate::unix::set_mtu(&iface_name, verified_mtu).map_err(Error::SetMtu)?;
+        talpid_net::unix::set_mtu(&iface_name, verified_mtu).map_err(Error::SetMtu)?;
         #[cfg(windows)]
         set_mtu_windows(verified_mtu, iface_name, ipv6).map_err(Error::SetMtu)?;
     } else {