TheArchive/tailscale
1
0
Fork 0
mirror of https://github.com/tailscale/tailscale.git synced 2025-04-01 05:52:24 +00:00
Code Issues Packages Projects Releases Wiki Activity

wgengine: avoid holding any locks during HandshakeDone

Browse Source 
Because wgLock is held while some wireguard-go methods run,
trying to hold wgLock during HandshakeDone potentially creates
lock cycles between wgengine and internals of wireguard-go.

Arguably wireguard-go should call HandshakeDone in a new goroutine,
but until its API promises that, don't make any assumptions here.

Maybe for #110.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
This commit is contained in:
David Crawshaw 2020-02-28 06:30:46 -05:00
parent 06bf0d980e
commit c576a57067
1 changed files with 30 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
wgengine/userspace.go
View File

@ -167,7 +167,7 @@ func newUserspaceEngineAdvanced(logf logger.Logf, tundev tun.Device, routerGen R
if ones, bits := allowedIPs[0].Mask.Size(); ones == bits && ones != 0 { if ones, bits := allowedIPs[0].Mask.Size(); ones == bits && ones != 0 {
var ip wgcfg.IP var ip wgcfg.IP
copy(ip.Addr[:], allowedIPs[0].IP.To16()) copy(ip.Addr[:], allowedIPs[0].IP.To16())
e.startPinger(peerKey, ip) go e.pinger(peerKey, ip)
return return
} }
} }
@ -226,11 +226,11 @@ func newUserspaceEngineAdvanced(logf logger.Logf, tundev tun.Device, routerGen R
return e, nil return e, nil
} }
// startPinger starts a goroutine that sends ping packets for a few seconds. // pinger sends ping packets for a few seconds.
// //
// These generated packets are used to ensure we trigger the spray logic in // These generated packets are used to ensure we trigger the spray logic in
// the magicsock package for NAT traversal. // the magicsock package for NAT traversal.
func (e *userspaceEngine) startPinger(peerKey wgcfg.Key, ip wgcfg.IP) { func (e *userspaceEngine) pinger(peerKey wgcfg.Key, ip wgcfg.IP) {
e.logf("generating initial ping traffic to %s (%v)", peerKey.ShortString(), ip) e.logf("generating initial ping traffic to %s (%v)", peerKey.ShortString(), ip)
var srcIP packet.IP var srcIP packet.IP
@ -264,7 +264,6 @@ func (e *userspaceEngine) startPinger(peerKey wgcfg.Key, ip wgcfg.IP) {
payload := []byte("magicsock_spray") // no meaning payload := []byte("magicsock_spray") // no meaning
go func() {
defer func() { defer func() {
e.mu.Lock() e.mu.Lock()
defer e.mu.Unlock() defer e.mu.Unlock()
@ -294,7 +293,6 @@ func (e *userspaceEngine) startPinger(peerKey wgcfg.Key, ip wgcfg.IP) {
ipid++ ipid++
e.wgdev.SendPacket(b) e.wgdev.SendPacket(b)
} }
}()
} }
// TODO(apenwarr): dnsDomains really ought to be in wgcfg.Config. // TODO(apenwarr): dnsDomains really ought to be in wgcfg.Config.