[#184] Supported freebsd and fuchsia TCP_FASTOPEN

Author: zonyitoo

src/relay/tcprelay/utils/tfo/bsd.rs

@@ -0,0 +1,113 @@
+//! TCP Fast Open wrappers
+
+use std::{
+    io::{self, Error},
+    mem,
+    net::{self, IpAddr, SocketAddr},
+    os::unix::io::AsRawFd,
+};
+
+use libc;
+use log::error;
+use net2::TcpBuilder;
+use tokio::net::{TcpListener, TcpStream};
+
+pub async fn bind_listener(addr: &SocketAddr) -> io::Result<TcpListener> {
+    let listener = net::TcpListener::bind(addr)?;
+
+    let fd = listener.as_raw_fd();
+
+    unsafe {
+        // TCP_FASTOPEN was supported since FreeBSD 12.0
+        //
+        // Example program:
+        // https://people.freebsd.org/~pkelsey/tfo-tools/tfo-srv.c
+
+        let enable: libc::c_int = 1;
+
+        let ret = libc::setsockopt(
+            fd,
+            libc::IPPROTO_TCP,
+            libc::TCP_FASTOPEN,
+            &enable as *const _ as *const libc::c_void,
+            mem::size_of_val(&enable) as libc::socklen_t,
+        );
+
+        if ret != 0 {
+            error!(
+                "Failed to listen on {} with TFO enabled, supported after FreeBSD 12.0, ...",
+                addr
+            );
+
+            return Err(Error::last_os_error());
+        }
+    }
+
+    TcpListener::from_std(listener)
+}
+
+pub async fn connect_stream(addr: &SocketAddr) -> io::Result<TcpStream> {
+    let builder = match addr.ip() {
+        IpAddr::V4(..) => TcpBuilder::new_v4()?,
+        IpAddr::V6(..) => TcpBuilder::new_v6()?,
+    };
+
+    // Build it first, to retrive the socket fd
+    let stream = builder.to_tcp_stream()?;
+    let sockfd = stream.as_raw_fd();
+
+    unsafe {
+        // TCP_FASTOPEN was supported since FreeBSD 12.0
+        //
+        // Example program:
+        // https://people.freebsd.org/~pkelsey/tfo-tools/tfo-client.c
+
+        let enable: libc::c_int = 1;
+
+        let ret = libc::setsockopt(
+            sockfd,
+            libc::IPPROTO_TCP,
+            libc::TCP_FASTOPEN,
+            &enable as *const _ as *const libc::c_void,
+            mem::size_of_val(&enable) as libc::socklen_t,
+        );
+
+        if ret != 0 {
+            error!(
+                "Failed to connect to {} with TFO enabled, supported after FreeBSD 12.0, ...",
+                addr
+            );
+
+            return Err(Error::last_os_error());
+        }
+
+        let (saddr, saddr_len) = addr2raw(addr);
+
+        let empty_buf: [u8; 0] = [];
+
+        let ret = libc::sendto(
+            sockfd,
+            empty_buf.as_ptr() as *const libc::c_void,
+            0,
+            0, // Yes, FreeBSD doesn't need MSG_FASTOPEN
+            saddr,
+            saddr_len,
+        );
+
+        if ret != 0 {
+            return Err(Error::last_os_error());
+        }
+    }
+
+    TcpStream::from_std(stream)
+}
+
+// Borrowed from net2
+fn addr2raw(addr: &SocketAddr) -> (*const libc::sockaddr, libc::socklen_t) {
+    use std::mem;
+
+    match *addr {
+        SocketAddr::V4(ref a) => (a as *const _ as *const _, mem::size_of_val(a) as libc::socklen_t),
+        SocketAddr::V6(ref a) => (a as *const _ as *const _, mem::size_of_val(a) as libc::socklen_t),
+    }
+}

src/relay/tcprelay/utils/tfo/mod.rs

@@ -15,6 +15,9 @@ cfg_if! {
             } else if #[cfg(target_os = "macos")] {
                 #[path = "macos.rs"]
                 mod sys;
+            } else if #[cfg(any(target_os = "freebsd", target_os = "fuchsia"))] {
+                #[path = "bsd.rs"]
+                mod sys;
             } else {
                 compile_error!("TFO is not supported on this platform yet");
             }