lib/connections: Update pfilter to pick up bugfix/oob stuff, support OOB connections (fixes #7636) (#7654)

go.mod

@@ -1,7 +1,7 @@
 module github.com/syncthing/syncthing
 
 require (
-	github.com/AudriusButkevicius/pfilter v0.0.0-20210218141631-7468b85d810a
+	github.com/AudriusButkevicius/pfilter v0.0.0-20210510194644-fad42c10c5ac
 	github.com/AudriusButkevicius/recli v0.0.5
 	github.com/alecthomas/kong v0.2.16
 	github.com/bkaradzic/go-lz4 v0.0.0-20160924222819-7224d8d8f27e

go.sum

@@ -7,8 +7,8 @@ dmitri.shuralyov.com/html/belt v0.0.0-20180602232347-f7d459c86be0/go.mod h1:JLBr
 dmitri.shuralyov.com/service/change v0.0.0-20181023043359-a85b471d5412/go.mod h1:a1inKt/atXimZ4Mv927x+r7UpyzRUf4emIoiiSC2TN4=
 dmitri.shuralyov.com/state v0.0.0-20180228185332-28bcc343414c/go.mod h1:0PRwlb0D6DFvNNtx+9ybjezNCa8XF0xaYcETyp6rHWU=
 git.apache.org/thrift.git v0.0.0-20180902110319-2566ecd5d999/go.mod h1:fPE2ZNJGynbRyZ4dJvy6G277gSllfV2HJqblrnkyeyg=
-github.com/AudriusButkevicius/pfilter v0.0.0-20210218141631-7468b85d810a h1:dUzIAgRmHLIUU0PT+OJ0X1WI5j1hlLbf+G420gUjIQg=
-github.com/AudriusButkevicius/pfilter v0.0.0-20210218141631-7468b85d810a/go.mod h1:1N0EEx/irz4B1qV17wW82TFbjQrE7oX316Cki6eDY0Q=
+github.com/AudriusButkevicius/pfilter v0.0.0-20210510194644-fad42c10c5ac h1:ua8XsAiW9JrUa97ioh+ZaZu2JeSMrhcQ2peBxSMrqSs=
+github.com/AudriusButkevicius/pfilter v0.0.0-20210510194644-fad42c10c5ac/go.mod h1:EEEtt5r8y0gGHlRFF2+cLx0WUy/rKHnjALmom5E0+74=
 github.com/AudriusButkevicius/recli v0.0.5 h1:xUa55PvWTHBm17T6RvjElRO3y5tALpdceH86vhzQ5wg=
 github.com/AudriusButkevicius/recli v0.0.5/go.mod h1:Q2E26yc6RvWWEz/TJ/goUp6yXvipYdJI096hpoaqsNs=
 github.com/Azure/go-ntlmssp v0.0.0-20200615164410-66371956d46c h1:/IBSNwUN8+eKzUzbJPqhK839ygXJ82sde8x3ogr6R28=
@@ -129,6 +129,7 @@ github.com/gogo/protobuf v1.2.0/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7a
 github.com/gogo/protobuf v1.2.1/go.mod h1:hp+jE20tsWTFYpLwKvXlhS1hjn+gTNwPg2I6zVXpSg4=
 github.com/gogo/protobuf v1.3.2 h1:Ov1cvc58UF3b5XjBnZv7+opcTcQFZebYjWzi34vdm4Q=
 github.com/gogo/protobuf v1.3.2/go.mod h1:P1XiOD3dCwIKUDQYPy72D8LYyHL2YPYrpS2s69NZV8Q=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b h1:VKtxabqXZkF25pY9ekfRL6a582T4P37/31XEstQ5p58=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/groupcache v0.0.0-20160516000752-02826c3e7903/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
 github.com/golang/groupcache v0.0.0-20190702054246-869f871628b6/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
@@ -141,6 +142,8 @@ github.com/golang/mock v1.2.0/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfb
 github.com/golang/mock v1.4.0/go.mod h1:UOMv5ysSaYNkG+OFQykRIcU/QvvxJf3p21QfJ2Bt3cw=
 github.com/golang/mock v1.4.4 h1:l75CXGRSwbaYNpl/Z2X1XIIAMSCquvXgpVZDhwEIJsc=
 github.com/golang/mock v1.4.4/go.mod h1:l3mdAwkq5BuhzHwde/uurv3sEJeZMXNpwsxVWU71h+4=
+github.com/golang/mock v1.5.0 h1:jlYHihg//f7RRwuPfptm04yp4s7O6Kw8EZiVYIGcH0g=
+github.com/golang/mock v1.5.0/go.mod h1:CWnOUgYIOo4TcNZ0wHX3YZCqsaM1I1Jvs6v3mP3KVu8=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
@@ -187,6 +190,7 @@ github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7/go.mod h1:Fecb
 github.com/grpc-ecosystem/go-grpc-middleware v1.0.1-0.20190118093823-f849b5445de4/go.mod h1:FiyG127CGDf3tlThmgyCl78X/SZQqEOJBCDaAfeWzPs=
 github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0/go.mod h1:8NvIoxWQoOIhqOTXgfV/d3M/q6VIi02HzZEHgUlZvzk=
 github.com/grpc-ecosystem/grpc-gateway v1.5.0/go.mod h1:RSKVYQBd5MCa4OVpNdGskqpgL2+G+NZTnrVHpWWfpdw=
+github.com/grpc-ecosystem/grpc-gateway v1.9.5 h1:UImYN5qQ8tuGpGE16ZmjvcTtTw24zw1QAp/SlnNrZhI=
 github.com/grpc-ecosystem/grpc-gateway v1.9.5/go.mod h1:vNeuVxBJEsws4ogUvrchl83t/GYV9WGTSLVdBhOQFDY=
 github.com/hashicorp/consul/api v1.3.0/go.mod h1:MmDNSzIMUjNpY/mQ398R4bk2FnqQLoPndWW5VkKPlCE=
 github.com/hashicorp/consul/sdk v0.3.0/go.mod h1:VKf9jXwCTEY1QZP2MOLRhb5i/I/ssyNV1vwHyQBF0x8=
@@ -261,6 +265,8 @@ github.com/marten-seemann/qtls v0.10.0 h1:ECsuYUKalRL240rRD4Ri33ISb7kAQ3qGDlrrl5
 github.com/marten-seemann/qtls v0.10.0/go.mod h1:UvMd1oaYDACI99/oZUYLzMCkBXQVT0aGm99sJhbT8hs=
 github.com/marten-seemann/qtls-go1-15 v0.1.1 h1:LIH6K34bPVttyXnUWixk0bzH6/N07VxbSabxn5A5gZQ=
 github.com/marten-seemann/qtls-go1-15 v0.1.1/go.mod h1:GyFwywLKkRt+6mfU99csTEY1joMZz5vmB1WNZH3P81I=
+github.com/marten-seemann/qtls-go1-15 v0.1.4 h1:RehYMOyRW8hPVEja1KBVsFVNSm35Jj9Mvs5yNoZZ28A=
+github.com/marten-seemann/qtls-go1-15 v0.1.4/go.mod h1:GyFwywLKkRt+6mfU99csTEY1joMZz5vmB1WNZH3P81I=
 github.com/maruel/panicparse v1.6.1 h1:803MjBzGcUgE1vYgg3UMNq3G1oyYeKkMu3t6hBS97x0=
 github.com/maruel/panicparse v1.6.1/go.mod h1:uoxI4w9gJL6XahaYPMq/z9uadrdr1SyHuQwV2q80Mm0=
 github.com/maruel/panicparse/v2 v2.1.1/go.mod h1:AeTWdCE4lcq8OKsLb6cHSj1RWHVSnV9HBCk7sKLF4Jg=
@@ -451,8 +457,6 @@ github.com/syncthing/notify v0.0.0-20210308121556-f45149b04939/go.mod h1:J0q59IW
 github.com/syndtr/goleveldb v1.0.1-0.20200815071216-d9e9293bd0f7 h1:udtnv1cokhJYqnUfCMCppJ71bFN9VKfG1BQ6UsYZnx8=
 github.com/syndtr/goleveldb v1.0.1-0.20200815071216-d9e9293bd0f7/go.mod h1:u2MKkTVTVJWe5D1rCvame8WqhBd88EuIwODJZ1VHCPM=
 github.com/tarm/serial v0.0.0-20180830185346-98f6abe2eb07/go.mod h1:kDXzergiv9cbyO7IOYJZWg1U88JhDg3PB6klq9Hg2pA=
-github.com/thejerf/suture/v4 v4.0.0 h1:GX3X+1Qaewtj9flL2wgoTBfLA5NcmrCY39TJRpPbUrI=
-github.com/thejerf/suture/v4 v4.0.0/go.mod h1:g0e8vwskm9tI0jRjxrnA6lSr0q6OfPdWJVX7G5bVWRs=
 github.com/thejerf/suture/v4 v4.0.1 h1:CLnC1wxLAiHA5zTbbvhSWMupVuGe5ZJ7YddWE3lvb4M=
 github.com/thejerf/suture/v4 v4.0.1/go.mod h1:g0e8vwskm9tI0jRjxrnA6lSr0q6OfPdWJVX7G5bVWRs=
 github.com/tklauser/go-sysconf v0.3.4/go.mod h1:Cl2c8ZRWfHD5IrfHo9VN+FX9kCFjIOyVklgXycLB6ek=
@@ -585,6 +589,7 @@ golang.org/x/sys v0.0.0-20200724161237-0e2f3a69832c/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200814200057-3d37ad5750ed/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201231184435-2d18734c6014/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210217105451-b926d437f341/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -647,6 +652,7 @@ google.golang.org/genproto v0.0.0-20190306203927-b5d61aea6440/go.mod h1:VzzqZJRn
 google.golang.org/genproto v0.0.0-20190307195333-5fe7a883aa19/go.mod h1:VzzqZJRnGkLBvHegQrXjBqPurQTc5/KpmUdxsrq26oE=
 google.golang.org/genproto v0.0.0-20190425155659-357c62f0e4bb/go.mod h1:VzzqZJRnGkLBvHegQrXjBqPurQTc5/KpmUdxsrq26oE=
 google.golang.org/genproto v0.0.0-20190530194941-fb225487d101/go.mod h1:z3L6/3dTEVtUr6QSP8miRzeRqwQOioJ9I66odjN4I7s=
+google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55 h1:gSJIx1SDwno+2ElGhA4+qG2zF97qiUzTM+rQ0klBOcE=
 google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55/go.mod h1:DMBHOl98Agz4BDEuKkezgsaosCRResVns1a3J2ZsMNc=
 google.golang.org/grpc v1.14.0/go.mod h1:yo6s7OP7yaDglbqo1J04qKzAhqBH6lvTonzMVmEdcZw=
 google.golang.org/grpc v1.16.0/go.mod h1:0JHn/cJsOMiMfNA9+DeHDlAU7KAAB5GDlYFpa9MZMio=
@@ -658,6 +664,7 @@ google.golang.org/grpc v1.21.0/go.mod h1:oYelfM1adQP15Ek0mdvEgi9Df8B9CZIaU1084ij
 google.golang.org/grpc v1.22.1/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyacEbxg=
 google.golang.org/grpc v1.23.0/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyacEbxg=
 google.golang.org/grpc v1.23.1/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyacEbxg=
+google.golang.org/grpc v1.26.0 h1:2dTRdpdFEEhJYQD8EMLB61nnrzSCTbG38PhqdhvOltg=
 google.golang.org/grpc v1.26.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=

lib/connections/quic_listen.go

@@ -83,18 +83,33 @@ func (t *quicListener) OnExternalAddressChanged(address *stun.Host, via string)
 func (t *quicListener) serve(ctx context.Context) error {
 	network := strings.ReplaceAll(t.uri.Scheme, "quic", "udp")
 
-	packetConn, err := net.ListenPacket(network, t.uri.Host)
+	udpAddr, err := net.ResolveUDPAddr(network, t.uri.Host)
 	if err != nil {
 		l.Infoln("Listen (BEP/quic):", err)
 		return err
 	}
-	defer packetConn.Close()
 
-	svc, conn := stun.New(t.cfg, t, packetConn)
+	udpConn, err := net.ListenUDP(network, udpAddr)
+	if err != nil {
+		l.Infoln("Listen (BEP/quic):", err)
+		return err
+	}
+	defer func() { _ = udpConn.Close() }()
+
+	svc, conn := stun.New(t.cfg, t, udpConn)
 	defer conn.Close()
-	wrapped := &stunConnQUICWrapper{
+
+	quicWrapper := quicWrapper{
 		PacketConn: conn,
-		underlying: packetConn.(*net.UDPConn),
+		underlying: udpConn,
+	}
+	var wrapped net.PacketConn = &quicWrapper
+
+	if oobConn, ok := conn.(oobConn); ok {
+		l.Debugf("wrapping in oob conn")
+		wrapped = &oobConnWrapper{
+			quicWrapper, oobConn,
+		}
 	}
 
 	go svc.Serve(ctx)
@@ -112,11 +127,11 @@ func (t *quicListener) serve(ctx context.Context) error {
 	t.notifyAddressesChanged(t)
 	defer t.clearAddresses(t)
 
-	l.Infof("QUIC listener (%v) starting", packetConn.LocalAddr())
-	defer l.Infof("QUIC listener (%v) shutting down", packetConn.LocalAddr())
+	l.Infof("QUIC listener (%v) starting", udpConn.LocalAddr())
+	defer l.Infof("QUIC listener (%v) shutting down", udpConn.LocalAddr())
 
 	t.mut.Lock()
-	t.laddr = packetConn.LocalAddr()
+	t.laddr = udpConn.LocalAddr()
 	t.mut.Unlock()
 	defer func() {
 		t.mut.Lock()
@@ -233,18 +248,32 @@ func (quicListenerFactory) Enabled(cfg config.Configuration) bool {
 	return true
 }
 
-// stunConnQUICWrapper provides methods used by quic.
-type stunConnQUICWrapper struct {
+// quicWrapper provides methods used by quic
+// https://github.com/lucas-clemente/quic-go/blob/master/packet_handler_map.go#L85
+type quicWrapper struct {
 	net.PacketConn
 	underlying *net.UDPConn
 }
 
-func (s *stunConnQUICWrapper) SetReadBuffer(size int) error {
-	// https://github.com/lucas-clemente/quic-go/blob/master/packet_handler_map.go#L85
+// SetReadBuffer is required by QUIC
+func (s *quicWrapper) SetReadBuffer(size int) error {
 	return s.underlying.SetReadBuffer(size)
 }
 
-func (s *stunConnQUICWrapper) SyscallConn() (syscall.RawConn, error) {
-	// https://github.com/lucas-clemente/quic-go/blob/84e03e59760ceee37359688871bb0688fcc4e98f/conn_windows.go#L18
+// SyscallConn is required by QUIC
+func (s *quicWrapper) SyscallConn() (syscall.RawConn, error) {
 	return s.underlying.SyscallConn()
 }
+
+// oobConn is used to assert that stun package returned a net.PacketConn that implements this interface.
+// If it does, we then wrap quicWrapper in oobConnWrapper, to expose those methods to QUIC package.
+type oobConn interface {
+	ReadMsgUDP(b, oob []byte) (n, oobn, flags int, addr *net.UDPAddr, err error)
+	WriteMsgUDP(b, oob []byte, addr *net.UDPAddr) (n, oobn int, err error)
+}
+
+// See: https://pkg.go.dev/github.com/lucas-clemente/quic-go#OOBCapablePacketConn
+type oobConnWrapper struct {
+	quicWrapper
+	oobConn
+}

lib/stun/stun.go

@@ -38,17 +38,35 @@ const (
 	NATSymmetricUDPFirewall = stun.NATSymmetricUDPFirewall
 )
 
-type writeTrackingPacketConn struct {
+type writeTrackingUdpConn struct {
 	lastWrite int64 // atomic, must remain 64-bit aligned
-	net.PacketConn
+	// Needs to be UDPConn not PacketConn, as pfilter checks for WriteMsgUDP/ReadMsgUDP
+	// and even if we embed UDPConn here, in place of a PacketConn, seems the interface
+	// check fails.
+	*net.UDPConn
 }
 
-func (c *writeTrackingPacketConn) WriteTo(p []byte, addr net.Addr) (n int, err error) {
+func (c *writeTrackingUdpConn) WriteTo(p []byte, addr net.Addr) (n int, err error) {
 	atomic.StoreInt64(&c.lastWrite, time.Now().Unix())
-	return c.PacketConn.WriteTo(p, addr)
+	return c.UDPConn.WriteTo(p, addr)
 }
 
-func (c *writeTrackingPacketConn) getLastWrite() time.Time {
+func (c *writeTrackingUdpConn) WriteMsgUDP(b, oob []byte, addr *net.UDPAddr) (n, oobn int, err error) {
+	atomic.StoreInt64(&c.lastWrite, time.Now().Unix())
+	return c.UDPConn.WriteMsgUDP(b, oob, addr)
+}
+
+func (c *writeTrackingUdpConn) WriteToUDP(b []byte, addr *net.UDPAddr) (int, error) {
+	atomic.StoreInt64(&c.lastWrite, time.Now().Unix())
+	return c.UDPConn.WriteToUDP(b, addr)
+}
+
+func (c *writeTrackingUdpConn) Write(b []byte) (int, error) {
+	atomic.StoreInt64(&c.lastWrite, time.Now().Unix())
+	return c.UDPConn.Write(b)
+}
+
+func (c *writeTrackingUdpConn) getLastWrite() time.Time {
 	unix := atomic.LoadInt64(&c.lastWrite)
 	return time.Unix(unix, 0)
 }
@@ -65,18 +83,18 @@ type Service struct {
 	stunConn   net.PacketConn
 	client     *stun.Client
 
-	writeTrackingPacketConn *writeTrackingPacketConn
+	writeTrackingUdpConn *writeTrackingUdpConn
 
 	natType NATType
 	addr    *Host
 }
 
-func New(cfg config.Wrapper, subscriber Subscriber, conn net.PacketConn) (*Service, net.PacketConn) {
+func New(cfg config.Wrapper, subscriber Subscriber, conn *net.UDPConn) (*Service, net.PacketConn) {
 	// Wrap the original connection to track writes on it
-	writeTrackingPacketConn := &writeTrackingPacketConn{lastWrite: 0, PacketConn: conn}
+	writeTrackingUdpConn := &writeTrackingUdpConn{lastWrite: 0, UDPConn: conn}
 
 	// Wrap it in a filter and split it up, so that stun packets arrive on stun conn, others arrive on the data conn
-	filterConn := pfilter.NewPacketFilter(writeTrackingPacketConn)
+	filterConn := pfilter.NewPacketFilter(writeTrackingUdpConn)
 	otherDataConn := filterConn.NewConn(otherDataPriority, nil)
 	stunConn := filterConn.NewConn(stunFilterPriority, &stunFilter{
 		ids: make(map[string]time.Time),
@@ -97,7 +115,7 @@ func New(cfg config.Wrapper, subscriber Subscriber, conn net.PacketConn) (*Servi
 		stunConn:   stunConn,
 		client:     client,
 
-		writeTrackingPacketConn: writeTrackingPacketConn,
+		writeTrackingUdpConn: writeTrackingUdpConn,
 
 		natType: NATUnknown,
 		addr:    nil,
@@ -241,7 +259,7 @@ func (s *Service) stunKeepAlive(ctx context.Context, addr string, extAddr *Host)
 		}
 
 		// Adjust the keepalives to fire only nextSleep after last write.
-		lastWrite := s.writeTrackingPacketConn.getLastWrite()
+		lastWrite := s.writeTrackingUdpConn.getLastWrite()
 		minSleep := time.Duration(s.cfg.Options().StunKeepaliveMinS) * time.Second
 		if nextSleep < minSleep {
 			nextSleep = minSleep
@@ -270,7 +288,7 @@ func (s *Service) stunKeepAlive(ctx context.Context, addr string, extAddr *Host)
 		}
 
 		// Check if any writes happened while we were sleeping, if they did, sleep again
-		lastWrite = s.writeTrackingPacketConn.getLastWrite()
+		lastWrite = s.writeTrackingUdpConn.getLastWrite()
 		if gap := time.Since(lastWrite); gap < nextSleep {
 			l.Debugf("%s stun last write gap less than next sleep: %s < %s. Will try later", s, gap, nextSleep)
 			goto tryLater