tailscale/net/tstun/linkattrs_linux.go
Will Norris 71029cea2d all: update copyright and license headers
This updates all source files to use a new standard header for copyright
and license declaration.  Notably, copyright no longer includes a date,
and we now use the standard SPDX-License-Identifier header.

This commit was done almost entirely mechanically with perl, and then
some minimal manual fixes.

Updates #6865

Signed-off-by: Will Norris <will@tailscale.com>
2023-01-27 15:36:29 -08:00

64 lines
1.5 KiB
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
package tstun
import (
"github.com/mdlayher/genetlink"
"github.com/mdlayher/netlink"
"github.com/tailscale/wireguard-go/tun"
"golang.org/x/sys/unix"
)
// setLinkSpeed sets the advertised link speed of the TUN interface.
func setLinkSpeed(iface tun.Device, mbps int) error {
name, err := iface.Name()
if err != nil {
return err
}
conn, err := genetlink.Dial(&netlink.Config{Strict: true})
if err != nil {
return err
}
defer conn.Close()
f, err := conn.GetFamily(unix.ETHTOOL_GENL_NAME)
if err != nil {
return err
}
ae := netlink.NewAttributeEncoder()
ae.Nested(unix.ETHTOOL_A_LINKMODES_HEADER, func(nae *netlink.AttributeEncoder) error {
nae.String(unix.ETHTOOL_A_HEADER_DEV_NAME, name)
return nil
})
ae.Uint32(unix.ETHTOOL_A_LINKMODES_SPEED, uint32(mbps))
b, err := ae.Encode()
if err != nil {
return err
}
_, err = conn.Execute(
genetlink.Message{
Header: genetlink.Header{
Command: unix.ETHTOOL_MSG_LINKMODES_SET,
Version: unix.ETHTOOL_GENL_VERSION,
},
Data: b,
},
f.ID,
netlink.Request|netlink.Acknowledge,
)
return err
}
// setLinkAttrs sets up link attributes that can be queried by external tools.
// Its failure is non-fatal to interface bringup.
func setLinkAttrs(iface tun.Device) error {
// By default the link speed is 10Mbps, which is easily exceeded and causes monitoring tools to complain (#3933).
return setLinkSpeed(iface, unix.SPEED_UNKNOWN)
}