TheArchive/tailscale
1
0
Fork 0
mirror of https://github.com/tailscale/tailscale.git synced 2025-01-05 23:07:44 +00:00
Code Issues Packages Projects Releases Wiki Activity

derp: account for increased size of peerPresent messages in mesh updates

Browse Source 
sendMeshUpdates tries to write as much as possible without blocking,
being careful to check the bufio.Writer.Available size before writes.

Except that regressed in 6c791f7d60fa which made those messages larger, which
meants we were doing network I/O with the Server mutex held.

Updates tailscale/corp#13945

Change-Id: Ic327071d2e37de262931b9b390cae32084811919
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This commit is contained in:
Brad Fitzpatrick 2024-06-24 14:31:48 -07:00 committed by Brad Fitzpatrick
parent 200d92121f
commit ded7734c36
1 changed files with 15 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
derp/derp_server.go
View File

@ -1630,6 +1630,11 @@ func (c *sclient) sendPong(data [8]byte) error {
return err
}
const (
peerGoneFrameLen = keyLen + 1
peerPresentFrameLen = keyLen + 16 + 2 + 1 // 16 byte IP + 2 byte port + 1 byte flags
)
// sendPeerGone sends a peerGone frame, without flushing.
func (c *sclient) sendPeerGone(peer key.NodePublic, reason PeerGoneReasonType) error {
switch reason {
@ -1639,7 +1644,7 @@ func (c *sclient) sendPeerGone(peer key.NodePublic, reason PeerGoneReasonType) e
c.s.peerGoneNotHereFrames.Add(1)
}
c.setWriteDeadline()
data := make([]byte, 0, keyLen+1)
data := make([]byte, 0, peerGoneFrameLen)
data = peer.AppendTo(data)
data = append(data, byte(reason))
if err := writeFrameHeader(c.bw.bw(), framePeerGone, uint32(len(data))); err != nil {
@ -1653,11 +1658,10 @@ func (c *sclient) sendPeerGone(peer key.NodePublic, reason PeerGoneReasonType) e
// sendPeerPresent sends a peerPresent frame, without flushing.
func (c *sclient) sendPeerPresent(peer key.NodePublic, ipPort netip.AddrPort, flags PeerPresentFlags) error {
c.setWriteDeadline()
const frameLen = keyLen + 16 + 2 + 1 // 16 byte IP + 2 byte port + 1 byte flags
if err := writeFrameHeader(c.bw.bw(), framePeerPresent, frameLen); err != nil {
if err := writeFrameHeader(c.bw.bw(), framePeerPresent, peerPresentFrameLen); err != nil {
return err
}
payload := make([]byte, frameLen)
payload := make([]byte, peerPresentFrameLen)
_ = peer.AppendTo(payload[:0])
a16 := ipPort.Addr().As16()
copy(payload[keyLen:], a16[:])
@ -1688,13 +1692,17 @@ func (c *sclient) sendMeshUpdates() error {
writes := 0
for _, pcs := range c.peerStateChange {
if c.bw.Available() <= frameHeaderLen+keyLen {
break
}
avail := c.bw.Available()
var err error
if pcs.present {
if avail <= frameHeaderLen+peerPresentFrameLen {
break
}
err = c.sendPeerPresent(pcs.peer, pcs.ipPort, pcs.flags)
} else {
if avail <= frameHeaderLen+peerGoneFrameLen {
break
}
err = c.sendPeerGone(pcs.peer, PeerGoneReasonDisconnected)
}
if err != nil {