retire stateless tokens when updating the connection ID

conn_id_manager.go

@@ -15,19 +15,22 @@ type connIDManager struct {
 	activeConnectionID        protocol.ConnectionID
 	activeStatelessResetToken *[16]byte
 
-	addStatelessResetToken func([16]byte)
-	queueControlFrame      func(wire.Frame)
+	addStatelessResetToken    func([16]byte)
+	retireStatelessResetToken func([16]byte)
+	queueControlFrame         func(wire.Frame)
 }
 
 func newConnIDManager(
 	initialDestConnID protocol.ConnectionID,
 	addStatelessResetToken func([16]byte),
+	retireStatelessResetToken func([16]byte),
 	queueControlFrame func(wire.Frame),
 ) *connIDManager {
 	return &connIDManager{
-		activeConnectionID:     initialDestConnID,
-		addStatelessResetToken: addStatelessResetToken,
-		queueControlFrame:      queueControlFrame,
+		activeConnectionID:        initialDestConnID,
+		addStatelessResetToken:    addStatelessResetToken,
+		retireStatelessResetToken: retireStatelessResetToken,
+		queueControlFrame:         queueControlFrame,
 	}
 }
 
@@ -98,10 +101,14 @@ func (h *connIDManager) updateConnectionID() {
 	h.queueControlFrame(&wire.RetireConnectionIDFrame{
 		SequenceNumber: h.activeSequenceNumber,
 	})
+	if h.activeStatelessResetToken != nil {
+		h.retireStatelessResetToken(*h.activeStatelessResetToken)
+	}
 	front := h.queue.Remove(h.queue.Front())
 	h.activeSequenceNumber = front.SequenceNumber
 	h.activeConnectionID = front.ConnectionID
 	h.activeStatelessResetToken = front.StatelessResetToken
+	h.addStatelessResetToken(*h.activeStatelessResetToken)
 }
 
 // is called when the server performs a Retry

conn_id_manager_test.go

@@ -9,18 +9,21 @@ import (
 
 var _ = Describe("Connection ID Manager", func() {
 	var (
-		m          *connIDManager
-		frameQueue []wire.Frame
-		tokenAdded *[16]byte
+		m             *connIDManager
+		frameQueue    []wire.Frame
+		tokenAdded    *[16]byte
+		retiredTokens [][16]byte
 	)
 	initialConnID := protocol.ConnectionID{1, 1, 1, 1}
 
 	BeforeEach(func() {
 		frameQueue = nil
 		tokenAdded = nil
+		retiredTokens = nil
 		m = newConnIDManager(
 			initialConnID,
 			func(token [16]byte) { tokenAdded = &token },
+			func(token [16]byte) { retiredTokens = append(retiredTokens, token) },
 			func(f wire.Frame,
 			) {
 				frameQueue = append(frameQueue, f)
@@ -138,12 +141,14 @@ var _ = Describe("Connection ID Manager", func() {
 	It("retires old connection IDs when the peer sends too many new ones", func() {
 		for i := uint8(1); i <= protocol.MaxActiveConnectionIDs; i++ {
 			Expect(m.Add(&wire.NewConnectionIDFrame{
-				SequenceNumber: uint64(i),
-				ConnectionID:   protocol.ConnectionID{i, i, i, i},
+				SequenceNumber:      uint64(i),
+				ConnectionID:        protocol.ConnectionID{i, i, i, i},
+				StatelessResetToken: [16]byte{i, i, i, i, i, i, i, i, i, i, i, i, i, i, i, i},
 			})).To(Succeed())
 		}
 		Expect(frameQueue).To(HaveLen(1))
 		Expect(frameQueue[0].(*wire.RetireConnectionIDFrame).SequenceNumber).To(BeZero())
+		Expect(retiredTokens).To(BeEmpty())
 		frameQueue = nil
 		Expect(m.Add(&wire.NewConnectionIDFrame{
 			SequenceNumber: protocol.MaxActiveConnectionIDs + 1,
@@ -151,5 +156,7 @@ var _ = Describe("Connection ID Manager", func() {
 		})).To(Succeed())
 		Expect(frameQueue).To(HaveLen(1))
 		Expect(frameQueue[0].(*wire.RetireConnectionIDFrame).SequenceNumber).To(BeEquivalentTo(1))
+		Expect(retiredTokens).To(HaveLen(1))
+		Expect(retiredTokens[0]).To(Equal([16]byte{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}))
 	})
 })

session.go

@@ -209,6 +209,7 @@ var newSession = func(
 	s.connIDManager = newConnIDManager(
 		destConnID,
 		func(token [16]byte) { runner.AddResetToken(token, s) },
+		runner.RetireResetToken,
 		s.queueControlFrame,
 	)
 	s.preSetup()
@@ -281,6 +282,7 @@ var newClientSession = func(
 	s.connIDManager = newConnIDManager(
 		destConnID,
 		func(token [16]byte) { runner.AddResetToken(token, s) },
+		runner.RetireResetToken,
 		s.queueControlFrame,
 	)
 	s.preSetup()