wgengine/netstack: replace a 1500 with a const + doc

Per post-submit code review feedback of 1336fb740b from @maisem.

Change-Id: Ic5c16306cbdee1029518448642304981f77ea1fd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This commit is contained in:
Brad Fitzpatrick 2022-06-02 08:17:12 -07:00 committed by Brad Fitzpatrick
parent e428bba7a3
commit 69b535c01f

View File

@ -133,6 +133,11 @@ type Impl struct {
const nicID = 1 const nicID = 1
const mtu = tstun.DefaultMTU const mtu = tstun.DefaultMTU
// maxUDPPacketSize is the maximum size of a UDP packet we copy in startPacketCopy
// when relaying UDP packets. We don't use the 'mtu' const in anticipation of
// one day making the MTU more dynamic.
const maxUDPPacketSize = 1500
// Create creates and populates a new Impl. // Create creates and populates a new Impl.
func Create(logf logger.Logf, tundev *tstun.Wrapper, e wgengine.Engine, mc *magicsock.Conn, dialer *tsdial.Dialer, dns *dns.Manager) (*Impl, error) { func Create(logf logger.Logf, tundev *tstun.Wrapper, e wgengine.Engine, mc *magicsock.Conn, dialer *tsdial.Dialer, dns *dns.Manager) (*Impl, error) {
if mc == nil { if mc == nil {
@ -1018,7 +1023,7 @@ func startPacketCopy(ctx context.Context, cancel context.CancelFunc, dst net.Pac
} }
go func() { go func() {
defer cancel() // tear down the other direction's copy defer cancel() // tear down the other direction's copy
pkt := make([]byte, 1500) pkt := make([]byte, maxUDPPacketSize)
for { for {
select { select {
case <-ctx.Done(): case <-ctx.Done():