tailscale/wgengine/magicsock/peermtu_linux.go
Val 055f3fd843 wgengine/magicsock: rename debugPMTUD() to debugEnablePMTUD()
Make the debugknob variable name for enabling peer path MTU discovery match the
env variable name.

Updates #311

Signed-off-by: Val <valerie@tailscale.com>
2023-09-21 04:17:12 -07:00

35 lines
805 B
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
//go:build linux && !android
package magicsock
import (
"net"
"syscall"
"tailscale.com/types/nettype"
)
func setDontFragment(pconn nettype.PacketConn, network string) (err error) {
if c, ok := pconn.(*net.UDPConn); ok {
rc, err := c.SyscallConn()
if err == nil {
rc.Control(func(fd uintptr) {
if network == "udp4" {
err = syscall.SetsockoptInt(int(fd), syscall.IPPROTO_IP, syscall.IP_MTU_DISCOVER, syscall.IP_PMTUDISC_DO)
}
if network == "udp6" {
err = syscall.SetsockoptInt(int(fd), syscall.IPPROTO_IPV6, syscall.IP_MTU_DISCOVER, syscall.IP_PMTUDISC_DO)
}
})
}
}
return err
}
func CanPMTUD() bool {
return debugEnablePMTUD() // only if the envknob is enabled, for now.
}