Regenerate SessionID on reconnection

cmd/ck-client/ck-client.go

@@ -127,7 +127,7 @@ func main() {
 	}
 
 	if *isAdmin {
-		sta := client.InitState("", "", "", "", time.Now, 0)
+		sta := client.InitState("", "", "", "", time.Now)
 		err := sta.ParseConfig(pluginOpts)
 		if err != nil {
 			log.Fatal(err)
@@ -139,12 +139,7 @@ func main() {
 		return
 	}
 
-	// sessionID is usergenerated. There shouldn't be a security concern because the scope of
-	// sessionID is limited to its UID.
-	rand.Seed(time.Now().UnixNano())
-	sessionID := rand.Uint32()
-
-	sta := client.InitState(localHost, localPort, remoteHost, remotePort, time.Now, sessionID)
+	sta := client.InitState(localHost, localPort, remoteHost, remotePort, time.Now)
 	err := sta.ParseConfig(pluginOpts)
 	if err != nil {
 		log.Fatal(err)
@@ -167,6 +162,11 @@ func main() {
 
 start:
 	log.Println("Attemtping to start a new session")
+	// sessionID is usergenerated. There shouldn't be a security concern because the scope of
+	// sessionID is limited to its UID.
+	rand.Seed(time.Now().UnixNano())
+	sessionID := rand.Uint32()
+	sta.SetSessionID(sessionID)
 	var UNLIMITED int64 = 1e12
 	valve := mux.MakeValve(1e12, 1e12, &UNLIMITED, &UNLIMITED)
 	obfs := mux.MakeObfs(sta.UID)

internal/client/state.go

@@ -42,19 +42,20 @@ type State struct {
 	NumConn        int
 }
 
-func InitState(localHost, localPort, remoteHost, remotePort string, nowFunc func() time.Time, sessionID uint32) *State {
+func InitState(localHost, localPort, remoteHost, remotePort string, nowFunc func() time.Time) *State {
 	ret := &State{
 		SS_LOCAL_HOST:  localHost,
 		SS_LOCAL_PORT:  localPort,
 		SS_REMOTE_HOST: remoteHost,
 		SS_REMOTE_PORT: remotePort,
 		Now:            nowFunc,
-		sessionID:      sessionID,
 	}
 	ret.keyPairs = make(map[int64]*keyPair)
 	return ret
 }
 
+func (sta *State) SetSessionID(id uint32) { sta.sessionID = id }
+
 // semi-colon separated value. This is for Android plugin options
 func ssvToJson(ssv string) (ret []byte) {
 	unescape := func(s string) string {