feat: add option to speedtest to dump a pcap of network traffic (#11848)

tailnet/conn.go

@@ -30,6 +30,7 @@ import (
 	tslogger "tailscale.com/types/logger"
 	"tailscale.com/types/netlogtype"
 	"tailscale.com/wgengine"
+	"tailscale.com/wgengine/capture"
 	"tailscale.com/wgengine/magicsock"
 	"tailscale.com/wgengine/netstack"
 	"tailscale.com/wgengine/router"
@@ -310,6 +311,12 @@ type Conn struct {
 	trafficStats *connstats.Statistics
 }
 
+func (c *Conn) InstallCaptureHook(f capture.Callback) {
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+	c.wireguardEngine.InstallCaptureHook(f)
+}
+
 func (c *Conn) MagicsockSetDebugLoggingEnabled(enabled bool) {
 	c.magicConn.SetDebugLoggingEnabled(enabled)
 }