From 2099d0bd87fe53aa98a7c02334852d279baeb779 Mon Sep 17 00:00:00 2001
From: Campbell He <duskmoon314@users.noreply.github.com>
Date: Wed, 10 Aug 2022 21:30:08 +0800
Subject: [PATCH] net: add `device` and `bind_device` methods to TCP/UDP
 sockets (#4882)

---
 tokio/src/net/tcp/socket.rs | 28 ++++++++++++++++++++++++++++
 tokio/src/net/udp.rs        | 28 ++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/tokio/src/net/tcp/socket.rs b/tokio/src/net/tcp/socket.rs
index a6605dc10ca..b00df95f4a6 100644
--- a/tokio/src/net/tcp/socket.rs
+++ b/tokio/src/net/tcp/socket.rs
@@ -453,6 +453,34 @@ impl TcpSocket {
         self.inner.set_tos(tos)
     }
 
+    /// Gets the value for the `SO_BINDTODEVICE` option on this socket
+    ///
+    /// This value gets the socket binded device's interface name.
+    #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux",))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux",)))
+    )]
+    pub fn device(&self) -> io::Result<Option<Vec<u8>>> {
+        self.inner.device()
+    }
+
+    /// Sets the value for the `SO_BINDTODEVICE` option on this socket
+    ///
+    /// If a socket is bound to an interface, only packets received from that
+    /// particular interface are processed by the socket. Note that this only
+    /// works for some socket types, particularly `AF_INET` sockets.
+    ///
+    /// If `interface` is `None` or an empty string it removes the binding.
+    #[cfg(all(any(target_os = "android", target_os = "fuchsia", target_os = "linux")))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(all(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))))
+    )]
+    pub fn bind_device(&self, interface: Option<&[u8]>) -> io::Result<()> {
+        self.inner.bind_device(interface)
+    }
+
     /// Gets the local address of this socket.
     ///
     /// Will fail on windows if called before `bind`.
diff --git a/tokio/src/net/udp.rs b/tokio/src/net/udp.rs
index 917e6769ed2..d2d4d4273a8 100644
--- a/tokio/src/net/udp.rs
+++ b/tokio/src/net/udp.rs
@@ -1569,6 +1569,34 @@ impl UdpSocket {
         self.as_socket().set_tos(tos)
     }
 
+    /// Gets the value for the `SO_BINDTODEVICE` option on this socket
+    ///
+    /// This value gets the socket binded device's interface name.
+    #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux",))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux",)))
+    )]
+    pub fn device(&self) -> io::Result<Option<Vec<u8>>> {
+        self.as_socket().device()
+    }
+
+    /// Sets the value for the `SO_BINDTODEVICE` option on this socket
+    ///
+    /// If a socket is bound to an interface, only packets received from that
+    /// particular interface are processed by the socket. Note that this only
+    /// works for some socket types, particularly `AF_INET` sockets.
+    ///
+    /// If `interface` is `None` or an empty string it removes the binding.
+    #[cfg(all(any(target_os = "android", target_os = "fuchsia", target_os = "linux")))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(all(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))))
+    )]
+    pub fn bind_device(&self, interface: Option<&[u8]>) -> io::Result<()> {
+        self.as_socket().bind_device(interface)
+    }
+
     /// Executes an operation of the `IP_ADD_MEMBERSHIP` type.
     ///
     /// This function specifies a new multicast group for this socket to join.