wireguard-go/conn/controlfns_linux.go

70 lines
2.0 KiB
Go

/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
*/
package conn
import (
"fmt"
"runtime"
"syscall"
"golang.org/x/sys/unix"
)
func init() {
controlFns = append(controlFns,
// Attempt to set the socket buffer size beyond net.core.{r,w}mem_max by
// using SO_*BUFFORCE. This requires CAP_NET_ADMIN, and is allowed here to
// fail silently - the result of failure is lower performance on very fast
// links or high latency links.
func(network, address string, c syscall.RawConn) error {
return c.Control(func(fd uintptr) {
// Set up to *mem_max
_ = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_RCVBUF, socketBufferSize)
_ = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_SNDBUF, socketBufferSize)
// Set beyond *mem_max if CAP_NET_ADMIN
_ = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_RCVBUFFORCE, socketBufferSize)
_ = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_SNDBUFFORCE, socketBufferSize)
})
},
// Enable receiving of the packet information (IP_PKTINFO for IPv4,
// IPV6_PKTINFO for IPv6) that is used to implement sticky socket support.
func(network, address string, c syscall.RawConn) error {
var err error
switch network {
case "udp4":
if runtime.GOOS != "android" {
c.Control(func(fd uintptr) {
err = unix.SetsockoptInt(int(fd), unix.IPPROTO_IP, unix.IP_PKTINFO, 1)
})
}
case "udp6":
c.Control(func(fd uintptr) {
if runtime.GOOS != "android" {
err = unix.SetsockoptInt(int(fd), unix.IPPROTO_IPV6, unix.IPV6_RECVPKTINFO, 1)
if err != nil {
return
}
}
err = unix.SetsockoptInt(int(fd), unix.IPPROTO_IPV6, unix.IPV6_V6ONLY, 1)
})
default:
err = fmt.Errorf("unhandled network: %s: %w", network, unix.EINVAL)
}
return err
},
// Attempt to enable UDP_GRO
func(network, address string, c syscall.RawConn) error {
c.Control(func(fd uintptr) {
_ = unix.SetsockoptInt(int(fd), unix.IPPROTO_UDP, unix.UDP_GRO, 1)
})
return nil
},
)
}