From ad22ed9d16c60fd8e9436ed6efab7594dd27b17d Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Thu, 30 Nov 2017 16:43:12 +0700
Subject: [PATCH] disable connection migration

Connection migration is complicated: We need to verify the new path, and
reset the congestion controller. In the IETF draft, connection migration
is still work in progress.
---
 session.go      |  8 --------
 session_test.go | 21 ++++-----------------
 2 files changed, 4 insertions(+), 25 deletions(-)

diff --git a/session.go b/session.go
index 06d6916f..a163f7ee 100644
--- a/session.go
+++ b/session.go
@@ -448,14 +448,6 @@ func (s *session) handlePacketImpl(p *receivedPacket) error {
 		hdr.Log()
 	}
 	// if the decryption failed, this might be a packet sent by an attacker
-	// don't update the remote address
-	if quicErr, ok := err.(*qerr.QuicError); ok && quicErr.ErrorCode == qerr.DecryptionFailure {
-		return err
-	}
-	if s.perspective == protocol.PerspectiveServer {
-		// update the remote address, even if unpacking failed for any other reason than a decryption error
-		s.conn.SetCurrentRemoteAddr(p.remoteAddr)
-	}
 	if err != nil {
 		return err
 	}
diff --git a/session_test.go b/session_test.go
index c847b9de..b26b8ff4 100644
--- a/session_test.go
+++ b/session_test.go
@@ -739,16 +739,17 @@ var _ = Describe("Session", func() {
 		})
 
 		Context("updating the remote address", func() {
-			It("sets the remote address", func() {
+			It("doesn't support connection migration", func() {
+				origAddr := sess.conn.(*mockConnection).remoteAddr
 				remoteIP := &net.IPAddr{IP: net.IPv4(192, 168, 0, 100)}
-				Expect(sess.conn.(*mockConnection).remoteAddr).ToNot(Equal(remoteIP))
+				Expect(origAddr).ToNot(Equal(remoteIP))
 				p := receivedPacket{
 					remoteAddr: remoteIP,
 					header:     &wire.Header{PacketNumber: 1337},
 				}
 				err := sess.handlePacketImpl(&p)
 				Expect(err).ToNot(HaveOccurred())
-				Expect(sess.conn.(*mockConnection).remoteAddr).To(Equal(remoteIP))
+				Expect(sess.conn.(*mockConnection).remoteAddr).To(Equal(origAddr))
 			})
 
 			It("doesn't change the remote address if authenticating the packet fails", func() {
@@ -767,20 +768,6 @@ var _ = Describe("Session", func() {
 				Expect(quicErr.ErrorCode).To(Equal(qerr.DecryptionFailure))
 				Expect(sess.conn.(*mockConnection).remoteAddr).To(Equal(remoteIP))
 			})
-
-			It("sets the remote address, if the packet is authenticated, but unpacking fails for another reason", func() {
-				testErr := errors.New("testErr")
-				remoteIP := &net.IPAddr{IP: net.IPv4(192, 168, 0, 100)}
-				Expect(sess.conn.(*mockConnection).remoteAddr).ToNot(Equal(remoteIP))
-				p := receivedPacket{
-					remoteAddr: remoteIP,
-					header:     &wire.Header{PacketNumber: 1337},
-				}
-				sess.unpacker.(*mockUnpacker).unpackErr = testErr
-				err := sess.handlePacketImpl(&p)
-				Expect(err).To(MatchError(testErr))
-				Expect(sess.conn.(*mockConnection).remoteAddr).To(Equal(remoteIP))
-			})
 		})
 	})