support outbound-bind-interface for Windows

bin/sslocal.rs

@@ -79,6 +79,7 @@ fn main() {
             (@arg OUTBOUND_RECV_BUFFER_SIZE: --("outbound-recv-buffer-size") +takes_value {validator::validate_u32} "Set outbound sockets' SO_RCVBUF option")
 
             (@arg OUTBOUND_BIND_ADDR: --("outbound-bind-addr") +takes_value alias("bind-addr") {validator::validate_ip_addr} "Bind address, outbound socket will bind this address")
+            (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set SO_BINDTODEVICE / IP_BOUND_IF / IP_UNICAST_IF option for outbound socket")
         );
 
         // FIXME: -6 is not a identifier, so we cannot build it with clap_app!
@@ -114,18 +115,10 @@ fn main() {
         #[cfg(any(target_os = "linux", target_os = "android"))]
         {
             app = clap_app!(@app (app)
-                (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set SO_BINDTODEVICE option for outbound socket")
                 (@arg OUTBOUND_FWMARK: --("outbound-fwmark") +takes_value {validator::validate_u32} "Set SO_MARK option for outbound socket")
             );
         }
 
-        #[cfg(any(target_os = "macos", target_os = "ios"))]
-        {
-            app = clap_app!(@app (app)
-                (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set IP_BOUND_IF option for outbound socket")
-            );
-        }
-
         #[cfg(feature = "local-redir")]
         {
             if RedirType::tcp_default() != RedirType::NotSupported {
@@ -414,7 +407,6 @@ fn main() {
             config.outbound_fwmark = Some(mark.parse::<u32>().expect("an unsigned integer for `outbound-fwmark`"));
         }
 
-        #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
         if let Some(iface) = matches.value_of("OUTBOUND_BIND_INTERFACE") {
             config.outbound_bind_interface = Some(iface.to_owned());
         }

bin/ssmanager.rs

@@ -50,6 +50,7 @@ fn main() {
                     Servers defined will be created when process is started.")
 
             (@arg OUTBOUND_BIND_ADDR: -b --("outbound-bind-addr") +takes_value alias("bind-addr") {validator::validate_ip_addr} "Bind address, outbound socket will bind this address")
+            (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set SO_BINDTODEVICE / IP_BOUND_IF / IP_UNICAST_IF option for outbound socket")
             (@arg SERVER_HOST: -s --("server-host") +takes_value "Host name or IP address of your remote server")
 
             (@arg MANAGER_ADDR: --("manager-addr") +takes_value alias("manager-address") {validator::validate_manager_addr} "ShadowSocks Manager (ssmgr) address, could be ip:port, domain:port or /path/to/unix.sock")
@@ -105,18 +106,10 @@ fn main() {
         #[cfg(any(target_os = "linux", target_os = "android"))]
         {
             app = clap_app!(@app (app)
-                (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set SO_BINDTODEVICE option for outbound socket")
                 (@arg OUTBOUND_FWMARK: --("outbound-fwmark") +takes_value {validator::validate_u32} "Set SO_MARK option for outbound socket")
             );
         }
 
-        #[cfg(any(target_os = "macos", target_os = "ios"))]
-        {
-            app = clap_app!(@app (app)
-                (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set IP_BOUND_IF option for outbound socket")
-            );
-        }
-
         #[cfg(feature = "multi-threaded")]
         {
             app = clap_app!(@app (app)
@@ -180,7 +173,6 @@ fn main() {
             config.outbound_fwmark = Some(mark.parse::<u32>().expect("an unsigned integer for `outbound-fwmark`"));
         }
 
-        #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
         if let Some(iface) = matches.value_of("OUTBOUND_BIND_INTERFACE") {
             config.outbound_bind_interface = Some(iface.to_owned());
         }

bin/ssserver.rs

@@ -44,6 +44,7 @@ fn main() {
             (@arg CONFIG: -c --config +takes_value required_unless("SERVER_ADDR") "Shadowsocks configuration file (https://shadowsocks.org/en/config/quick-guide.html)")
 
             (@arg OUTBOUND_BIND_ADDR: -b --("outbound-bind-addr") +takes_value alias("bind-addr") {validator::validate_ip_addr} "Bind address, outbound socket will bind this address")
+            (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set SO_BINDTODEVICE / IP_BOUND_IF / IP_UNICAST_IF option for outbound socket")
 
             (@arg SERVER_ADDR: -s --("server-addr") +takes_value {validator::validate_server_addr} requires[PASSWORD ENCRYPT_METHOD] "Server address")
             (@arg PASSWORD: -k --password +takes_value requires[SERVER_ADDR] "Server's password")
@@ -100,18 +101,10 @@ fn main() {
         #[cfg(any(target_os = "linux", target_os = "android"))]
         {
             app = clap_app!(@app (app)
-                (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set SO_BINDTODEVICE option for outbound socket")
                 (@arg OUTBOUND_FWMARK: --("outbound-fwmark") +takes_value {validator::validate_u32} "Set SO_MARK option for outbound socket")
             );
         }
 
-        #[cfg(any(target_os = "macos", target_os = "ios"))]
-        {
-            app = clap_app!(@app (app)
-                (@arg OUTBOUND_BIND_INTERFACE: --("outbound-bind-interface") +takes_value "Set IP_BOUND_IF option for outbound socket")
-            );
-        }
-
         #[cfg(feature = "multi-threaded")]
         {
             app = clap_app!(@app (app)
@@ -214,7 +207,6 @@ fn main() {
             config.outbound_fwmark = Some(mark.parse::<u32>().expect("an unsigned integer for `outbound-fwmark`"));
         }
 
-        #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
         if let Some(iface) = matches.value_of("OUTBOUND_BIND_INTERFACE") {
             config.outbound_bind_interface = Some(iface.to_owned());
         }

crates/shadowsocks-service/src/config.rs

@@ -963,8 +963,7 @@ pub struct Config {
     /// Set `SO_MARK` socket option for outbound sockets
     #[cfg(any(target_os = "linux", target_os = "android"))]
     pub outbound_fwmark: Option<u32>,
-    /// Set `SO_BINDTODEVICE` socket option for outbound sockets
-    #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
+    /// Set `SO_BINDTODEVICE` (Linux), `IP_BOUND_IF` (BSD), `IP_UNICAST_IF` (Windows) socket option for outbound sockets
     pub outbound_bind_interface: Option<String>,
     /// Outbound sockets will `bind` to this address
     pub outbound_bind_addr: Option<IpAddr>,
@@ -1088,7 +1087,6 @@ impl Config {
 
             #[cfg(any(target_os = "linux", target_os = "android"))]
             outbound_fwmark: None,
-            #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
             outbound_bind_interface: None,
             outbound_bind_addr: None,
             #[cfg(target_os = "android")]

crates/shadowsocks-service/src/local/mod.rs

@@ -104,9 +104,7 @@ pub async fn create(config: Config) -> io::Result<Server> {
         #[cfg(target_os = "android")]
         vpn_protect_path: config.outbound_vpn_protect_path,
 
-        #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
         bind_interface: config.outbound_bind_interface,
-
         bind_local_addr: config.outbound_bind_addr,
 
         ..Default::default()

crates/shadowsocks-service/src/manager/mod.rs

@@ -41,8 +41,6 @@ pub async fn run(config: Config) -> io::Result<()> {
         vpn_protect_path: config.outbound_vpn_protect_path,
 
         bind_local_addr: config.outbound_bind_addr,
-
-        #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
         bind_interface: config.outbound_bind_interface,
 
         ..Default::default()

crates/shadowsocks-service/src/server/mod.rs

@@ -58,8 +58,6 @@ pub async fn run(config: Config) -> io::Result<()> {
         vpn_protect_path: config.outbound_vpn_protect_path,
 
         bind_local_addr: config.outbound_bind_addr,
-
-        #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
         bind_interface: config.outbound_bind_interface,
 
         ..Default::default()

crates/shadowsocks/src/net/option.rs

@@ -41,7 +41,6 @@ pub struct ConnectOpts {
     pub bind_local_addr: Option<IpAddr>,
 
     /// Outbound socket binds to interface
-    #[cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios"))]
     pub bind_interface: Option<String>,
 
     /// TCP options

crates/shadowsocks/src/net/sys/windows/mod.rs

@@ -1,4 +1,5 @@
 use std::{
+    ffi::CString,
     io::{self, ErrorKind},
     mem,
     net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr},
@@ -20,7 +21,10 @@ use winapi::{
     ctypes::{c_char, c_int},
     shared::{
         minwindef::{BOOL, DWORD, FALSE, LPDWORD, LPVOID},
-        ws2def::IPPROTO_TCP,
+        netioapi::if_nametoindex,
+        ntdef::PCSTR,
+        ws2def::{IPPROTO_IP, IPPROTO_IPV6, IPPROTO_TCP},
+        ws2ipdef::IPV6_UNICAST_IF,
     },
     um::{
         mswsock::SIO_UDP_CONNRESET,
@@ -35,6 +39,10 @@ use crate::net::{sys::set_common_sockopt_for_connect, AddrFamily, ConnectOpts};
 // https://github.com/retep998/winapi-rs/issues/856
 const TCP_FASTOPEN: DWORD = 15;
 
+// ws2ipdef.h
+// https://github.com/retep998/winapi-rs/pull/1007
+const IP_UNICAST_IF: DWORD = 31;
+
 /// A `TcpStream` that supports TFO (TCP Fast Open)
 #[pin_project(project = TcpStreamProj)]
 pub enum TcpStream {
@@ -49,6 +57,11 @@ impl TcpStream {
             SocketAddr::V6(..) => TcpSocket::new_v6()?,
         };
 
+        // Binds to a specific network interface (device)
+        if let Some(ref iface) = opts.bind_interface {
+            set_ip_unicast_if(&socket, addr, iface)?;
+        }
+
         set_common_sockopt_for_connect(addr, &socket, opts)?;
 
         if !opts.tcp.fastopen {
@@ -166,6 +179,51 @@ pub fn set_tcp_fastopen<S: AsRawSocket>(socket: &S) -> io::Result<()> {
     Ok(())
 }
 
+fn set_ip_unicast_if<S: AsRawSocket>(socket: &S, addr: SocketAddr, iface: &str) -> io::Result<()> {
+    let handle = socket.as_raw_socket() as SOCKET;
+
+    unsafe {
+        // Windows if_nametoindex requires a C-string for interface name
+        let ifname = CString::new(iface);
+
+        // https://docs.microsoft.com/en-us/previous-versions/windows/hardware/drivers/ff553788(v=vs.85)
+        let if_index = if_nametoindex(ifname.as_ptr() as PCSTR);
+        if if_name == 0 {
+            // If the if_nametoindex function fails and returns zero, it is not possible to determine an error code.
+            error!("if_nametoindex {} fails", iface);
+            return Err(io::Error::new(ErrorKind::InvalidInput, "invalid interface name"));
+        }
+
+        // https://docs.microsoft.com/en-us/windows/win32/winsock/ipproto-ip-socket-options
+        let if_index = if_index as DWORD;
+
+        let ret = match addr {
+            SocketAddr::V4(..) => setsockopt(
+                handle,
+                IPPROTO_IP as c_int,
+                IP_UNICAST_IF,
+                &if_index as *const _ as *const c_char,
+                mem::size_of_val(&if_index) as c_int,
+            ),
+            SocketAddr::V6(..) => setsockopt(
+                handle,
+                IPPROTO_IPV6 as c_int,
+                IPV6_UNICAST_IF,
+                &if_index as *const _ as *const c_char,
+                mem::size_of_val(&if_index) as c_int,
+            ),
+        };
+
+        if ret == SOCKET_ERROR {
+            let err = io::Error::from_raw_os_error(WSAGetLastError());
+            error!("set IP_UNICAST_IF / IPV6_UNICAST_IF error: {}", err);
+            return Err(err);
+        }
+    }
+
+    Ok(())
+}
+
 fn disable_connection_reset(socket: &UdpSocket) -> io::Result<()> {
     let handle = socket.as_raw_socket() as SOCKET;
 
@@ -271,6 +329,10 @@ pub async fn create_outbound_udp_socket(af: AddrFamily, opts: &ConnectOpts) -> i
     let socket = UdpSocket::bind(bind_addr).await?;
     disable_connection_reset(&socket)?;
 
+    if let Some(ref iface) = opts.bind_interface {
+        set_ip_unicast_if(&socket, bind_addr, iface)?;
+    }
+
     Ok(socket)
 }