1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
//go:build linux
// +build linux
/*
* This file is part of Go Responsiveness.
*
* Go Responsiveness is free software: you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by the Free Software Foundation,
* either version 2 of the License, or (at your option) any later version.
* Go Responsiveness is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with Go Responsiveness. If not, see <https://www.gnu.org/licenses/>.
*/
package l4s
import (
"crypto/tls"
"fmt"
"net"
"syscall"
)
func SetL4S(conn net.Conn, algorithm *string) error {
if algorithm == nil {
panic("Attempting to set L4S congestion control without specifying a congestion control algorithm.")
}
tlsConn, ok := conn.(*tls.Conn)
if !ok {
return fmt.Errorf("when setting L4S congestion control algorithm, outermost connection is not a TLS connection")
}
tcpConn, ok := tlsConn.NetConn().(*net.TCPConn)
if !ok {
return fmt.Errorf("when setting L4S congestion control algorithm, could not get the underlying IP connection")
}
rawConn, err := tcpConn.SyscallConn()
if err != nil {
return fmt.Errorf("when setting L4S congestion control algorithm, could not get the underlying raw connection")
}
var sockoptError error = nil
rawConn.Control(func(fd uintptr) {
sockoptError = syscall.SetsockoptString(int(fd), syscall.IPPROTO_TCP, syscall.TCP_CONGESTION, *algorithm)
})
if sockoptError != nil {
return fmt.Errorf("when setting L4S congestion control algorithm, could not set the algorithm to %v: %v", *algorithm, sockoptError.Error())
}
return nil
}
|
