v1.0.0

transport/internet/sockopt_linux.go

@@ -0,0 +1,120 @@
+package internet
+
+import (
+	"net"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+const (
+	// For incoming connections.
+	TCP_FASTOPEN = 23
+	// For out-going connections.
+	TCP_FASTOPEN_CONNECT = 30
+)
+
+func bindAddr(fd uintptr, ip []byte, port uint32) error {
+	setReuseAddr(fd)
+	setReusePort(fd)
+
+	var sockaddr syscall.Sockaddr
+
+	switch len(ip) {
+	case net.IPv4len:
+		a4 := &syscall.SockaddrInet4{
+			Port: int(port),
+		}
+		copy(a4.Addr[:], ip)
+		sockaddr = a4
+	case net.IPv6len:
+		a6 := &syscall.SockaddrInet6{
+			Port: int(port),
+		}
+		copy(a6.Addr[:], ip)
+		sockaddr = a6
+	default:
+		return newError("unexpected length of ip")
+	}
+
+	return syscall.Bind(int(fd), sockaddr)
+}
+
+func applyOutboundSocketOptions(network string, address string, fd uintptr, config *SocketConfig) error {
+	if config.Mark != 0 {
+		if err := syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK, int(config.Mark)); err != nil {
+			return newError("failed to set SO_MARK").Base(err)
+		}
+	}
+
+	if isTCPSocket(network) {
+		switch config.Tfo {
+		case SocketConfig_Enable:
+			if err := syscall.SetsockoptInt(int(fd), syscall.SOL_TCP, TCP_FASTOPEN_CONNECT, 1); err != nil {
+				return newError("failed to set TCP_FASTOPEN_CONNECT=1").Base(err)
+			}
+		case SocketConfig_Disable:
+			if err := syscall.SetsockoptInt(int(fd), syscall.SOL_TCP, TCP_FASTOPEN_CONNECT, 0); err != nil {
+				return newError("failed to set TCP_FASTOPEN_CONNECT=0").Base(err)
+			}
+		}
+	}
+
+	if config.Tproxy.IsEnabled() {
+		if err := syscall.SetsockoptInt(int(fd), syscall.SOL_IP, syscall.IP_TRANSPARENT, 1); err != nil {
+			return newError("failed to set IP_TRANSPARENT").Base(err)
+		}
+	}
+
+	return nil
+}
+
+func applyInboundSocketOptions(network string, fd uintptr, config *SocketConfig) error {
+	if config.Mark != 0 {
+		if err := syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_MARK, int(config.Mark)); err != nil {
+			return newError("failed to set SO_MARK").Base(err)
+		}
+	}
+	if isTCPSocket(network) {
+		switch config.Tfo {
+		case SocketConfig_Enable:
+			if err := syscall.SetsockoptInt(int(fd), syscall.SOL_TCP, TCP_FASTOPEN, 1); err != nil {
+				return newError("failed to set TCP_FASTOPEN=1").Base(err)
+			}
+		case SocketConfig_Disable:
+			if err := syscall.SetsockoptInt(int(fd), syscall.SOL_TCP, TCP_FASTOPEN, 0); err != nil {
+				return newError("failed to set TCP_FASTOPEN=0").Base(err)
+			}
+		}
+	}
+
+	if config.Tproxy.IsEnabled() {
+		if err := syscall.SetsockoptInt(int(fd), syscall.SOL_IP, syscall.IP_TRANSPARENT, 1); err != nil {
+			return newError("failed to set IP_TRANSPARENT").Base(err)
+		}
+	}
+
+	if config.ReceiveOriginalDestAddress && isUDPSocket(network) {
+		err1 := syscall.SetsockoptInt(int(fd), syscall.SOL_IPV6, unix.IPV6_RECVORIGDSTADDR, 1)
+		err2 := syscall.SetsockoptInt(int(fd), syscall.SOL_IP, syscall.IP_RECVORIGDSTADDR, 1)
+		if err1 != nil && err2 != nil {
+			return err1
+		}
+	}
+
+	return nil
+}
+
+func setReuseAddr(fd uintptr) error {
+	if err := syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1); err != nil {
+		return newError("failed to set SO_REUSEADDR").Base(err).AtWarning()
+	}
+	return nil
+}
+
+func setReusePort(fd uintptr) error {
+	if err := syscall.SetsockoptInt(int(fd), syscall.SOL_SOCKET, unix.SO_REUSEPORT, 1); err != nil {
+		return newError("failed to set SO_REUSEPORT").Base(err).AtWarning()
+	}
+	return nil
+}