Remove reundant global tcpip.LinkEndpointID.

PiperOrigin-RevId: 267709597

11 files changed, 38 insertions, 45 deletions

diff --git a/pkg/tcpip/link/channel/channel.go b/pkg/tcpip/link/channel/channel.go
index c40744b8e..eec430d0a 100644
--- a/pkg/tcpip/link/channel/channel.go
+++ b/pkg/tcpip/link/channel/channel.go
@@ -44,14 +44,12 @@ type Endpoint struct {
 }
 
 // New creates a new channel endpoint.
-func New(size int, mtu uint32, linkAddr tcpip.LinkAddress) (tcpip.LinkEndpointID, *Endpoint) {
-	e := &Endpoint{
+func New(size int, mtu uint32, linkAddr tcpip.LinkAddress) *Endpoint {
+	return &Endpoint{
 		C:        make(chan PacketInfo, size),
 		mtu:      mtu,
 		linkAddr: linkAddr,
 	}
-
-	return stack.RegisterLinkEndpoint(e), e
 }
 
 // Drain removes all outbound packets from the channel and counts them.
diff --git a/pkg/tcpip/link/fdbased/endpoint.go b/pkg/tcpip/link/fdbased/endpoint.go
index 77f988b9f..adcf21371 100644
--- a/pkg/tcpip/link/fdbased/endpoint.go
+++ b/pkg/tcpip/link/fdbased/endpoint.go
@@ -165,7 +165,7 @@ type Options struct {
 //
 // Makes fd non-blocking, but does not take ownership of fd, which must remain
 // open for the lifetime of the returned endpoint.
-func New(opts *Options) (tcpip.LinkEndpointID, error) {
+func New(opts *Options) (stack.LinkEndpoint, error) {
 	caps := stack.LinkEndpointCapabilities(0)
 	if opts.RXChecksumOffload {
 		caps |= stack.CapabilityRXChecksumOffload
@@ -190,7 +190,7 @@ func New(opts *Options) (tcpip.LinkEndpointID, error) {
 	}
 
 	if len(opts.FDs) == 0 {
-		return 0, fmt.Errorf("opts.FD is empty, at least one FD must be specified")
+		return nil, fmt.Errorf("opts.FD is empty, at least one FD must be specified")
 	}
 
 	e := &endpoint{
@@ -207,12 +207,12 @@ func New(opts *Options) (tcpip.LinkEndpointID, error) {
 	for i := 0; i < len(e.fds); i++ {
 		fd := e.fds[i]
 		if err := syscall.SetNonblock(fd, true); err != nil {
-			return 0, fmt.Errorf("syscall.SetNonblock(%v) failed: %v", fd, err)
+			return nil, fmt.Errorf("syscall.SetNonblock(%v) failed: %v", fd, err)
 		}
 
 		isSocket, err := isSocketFD(fd)
 		if err != nil {
-			return 0, err
+			return nil, err
 		}
 		if isSocket {
 			if opts.GSOMaxSize != 0 {
@@ -222,12 +222,12 @@ func New(opts *Options) (tcpip.LinkEndpointID, error) {
 		}
 		inboundDispatcher, err := createInboundDispatcher(e, fd, isSocket)
 		if err != nil {
-			return 0, fmt.Errorf("createInboundDispatcher(...) = %v", err)
+			return nil, fmt.Errorf("createInboundDispatcher(...) = %v", err)
 		}
 		e.inboundDispatchers = append(e.inboundDispatchers, inboundDispatcher)
 	}
 
-	return stack.RegisterLinkEndpoint(e), nil
+	return e, nil
 }
 
 func createInboundDispatcher(e *endpoint, fd int, isSocket bool) (linkDispatcher, error) {
@@ -435,14 +435,12 @@ func (e *InjectableEndpoint) Inject(protocol tcpip.NetworkProtocolNumber, vv buf
 }
 
 // NewInjectable creates a new fd-based InjectableEndpoint.
-func NewInjectable(fd int, mtu uint32, capabilities stack.LinkEndpointCapabilities) (tcpip.LinkEndpointID, *InjectableEndpoint) {
+func NewInjectable(fd int, mtu uint32, capabilities stack.LinkEndpointCapabilities) *InjectableEndpoint {
 	syscall.SetNonblock(fd, true)
 
-	e := &InjectableEndpoint{endpoint: endpoint{
+	return &InjectableEndpoint{endpoint: endpoint{
 		fds:  []int{fd},
 		mtu:  mtu,
 		caps: capabilities,
 	}}
-
-	return stack.RegisterLinkEndpoint(e), e
 }
diff --git a/pkg/tcpip/link/fdbased/endpoint_test.go b/pkg/tcpip/link/fdbased/endpoint_test.go
index e305252d6..04406bc9a 100644
--- a/pkg/tcpip/link/fdbased/endpoint_test.go
+++ b/pkg/tcpip/link/fdbased/endpoint_test.go
@@ -68,11 +68,10 @@ func newContext(t *testing.T, opt *Options) *context {
 	}
 
 	opt.FDs = []int{fds[1]}
-	epID, err := New(opt)
+	ep, err := New(opt)
 	if err != nil {
 		t.Fatalf("Failed to create FD endpoint: %v", err)
 	}
-	ep := stack.FindLinkEndpoint(epID).(*endpoint)
 
 	c := &context{
 		t:    t,
diff --git a/pkg/tcpip/link/loopback/loopback.go b/pkg/tcpip/link/loopback/loopback.go
index ab6a53988..e121ea1a5 100644
--- a/pkg/tcpip/link/loopback/loopback.go
+++ b/pkg/tcpip/link/loopback/loopback.go
@@ -32,8 +32,8 @@ type endpoint struct {
 
 // New creates a new loopback endpoint. This link-layer endpoint just turns
 // outbound packets into inbound packets.
-func New() tcpip.LinkEndpointID {
-	return stack.RegisterLinkEndpoint(&endpoint{})
+func New() stack.LinkEndpoint {
+	return &endpoint{}
 }
 
 // Attach implements stack.LinkEndpoint.Attach. It just saves the stack network-
diff --git a/pkg/tcpip/link/muxed/injectable.go b/pkg/tcpip/link/muxed/injectable.go
index a577a3d52..3ed7b98d1 100644
--- a/pkg/tcpip/link/muxed/injectable.go
+++ b/pkg/tcpip/link/muxed/injectable.go
@@ -105,9 +105,8 @@ func (m *InjectableEndpoint) WriteRawPacket(dest tcpip.Address, packet []byte) *
 }
 
 // NewInjectableEndpoint creates a new multi-endpoint injectable endpoint.
-func NewInjectableEndpoint(routes map[tcpip.Address]stack.InjectableLinkEndpoint) (tcpip.LinkEndpointID, *InjectableEndpoint) {
-	e := &InjectableEndpoint{
+func NewInjectableEndpoint(routes map[tcpip.Address]stack.InjectableLinkEndpoint) *InjectableEndpoint {
+	return &InjectableEndpoint{
 		routes: routes,
 	}
-	return stack.RegisterLinkEndpoint(e), e
 }
diff --git a/pkg/tcpip/link/muxed/injectable_test.go b/pkg/tcpip/link/muxed/injectable_test.go
index 174b9330f..3086fec00 100644
--- a/pkg/tcpip/link/muxed/injectable_test.go
+++ b/pkg/tcpip/link/muxed/injectable_test.go
@@ -87,8 +87,8 @@ func makeTestInjectableEndpoint(t *testing.T) (*InjectableEndpoint, *os.File, tc
 	if err != nil {
 		t.Fatal("Failed to create socket pair:", err)
 	}
-	_, underlyingEndpoint := fdbased.NewInjectable(pair[1], 6500, stack.CapabilityNone)
+	underlyingEndpoint := fdbased.NewInjectable(pair[1], 6500, stack.CapabilityNone)
 	routes := map[tcpip.Address]stack.InjectableLinkEndpoint{dstIP: underlyingEndpoint}
-	_, endpoint := NewInjectableEndpoint(routes)
+	endpoint := NewInjectableEndpoint(routes)
 	return endpoint, os.NewFile(uintptr(pair[0]), "test route end"), dstIP
 }
diff --git a/pkg/tcpip/link/sharedmem/sharedmem.go b/pkg/tcpip/link/sharedmem/sharedmem.go
index 834ea5c40..ba387af73 100644
--- a/pkg/tcpip/link/sharedmem/sharedmem.go
+++ b/pkg/tcpip/link/sharedmem/sharedmem.go
@@ -94,7 +94,7 @@ type endpoint struct {
 
 // New creates a new shared-memory-based endpoint. Buffers will be broken up
 // into buffers of "bufferSize" bytes.
-func New(mtu, bufferSize uint32, addr tcpip.LinkAddress, tx, rx QueueConfig) (tcpip.LinkEndpointID, error) {
+func New(mtu, bufferSize uint32, addr tcpip.LinkAddress, tx, rx QueueConfig) (stack.LinkEndpoint, error) {
 	e := &endpoint{
 		mtu:        mtu,
 		bufferSize: bufferSize,
@@ -102,15 +102,15 @@ func New(mtu, bufferSize uint32, addr tcpip.LinkAddress, tx, rx QueueConfig) (tc
 	}
 
 	if err := e.tx.init(bufferSize, &tx); err != nil {
-		return 0, err
+		return nil, err
 	}
 
 	if err := e.rx.init(bufferSize, &rx); err != nil {
 		e.tx.cleanup()
-		return 0, err
+		return nil, err
 	}
 
-	return stack.RegisterLinkEndpoint(e), nil
+	return e, nil
 }
 
 // Close frees all resources associated with the endpoint.
diff --git a/pkg/tcpip/link/sharedmem/sharedmem_test.go b/pkg/tcpip/link/sharedmem/sharedmem_test.go
index 98036f367..0e9ba0846 100644
--- a/pkg/tcpip/link/sharedmem/sharedmem_test.go
+++ b/pkg/tcpip/link/sharedmem/sharedmem_test.go
@@ -119,12 +119,12 @@ func newTestContext(t *testing.T, mtu, bufferSize uint32, addr tcpip.LinkAddress
 	initQueue(t, &c.txq, &c.txCfg)
 	initQueue(t, &c.rxq, &c.rxCfg)
 
-	id, err := New(mtu, bufferSize, addr, c.txCfg, c.rxCfg)
+	ep, err := New(mtu, bufferSize, addr, c.txCfg, c.rxCfg)
 	if err != nil {
 		t.Fatalf("New failed: %v", err)
 	}
 
-	c.ep = stack.FindLinkEndpoint(id).(*endpoint)
+	c.ep = ep.(*endpoint)
 	c.ep.Attach(c)
 
 	return c
diff --git a/pkg/tcpip/link/sniffer/sniffer.go b/pkg/tcpip/link/sniffer/sniffer.go
index 36c8c46fc..e7b6d7912 100644
--- a/pkg/tcpip/link/sniffer/sniffer.go
+++ b/pkg/tcpip/link/sniffer/sniffer.go
@@ -58,10 +58,10 @@ type endpoint struct {
 
 // New creates a new sniffer link-layer endpoint. It wraps around another
 // endpoint and logs packets and they traverse the endpoint.
-func New(lower tcpip.LinkEndpointID) tcpip.LinkEndpointID {
-	return stack.RegisterLinkEndpoint(&endpoint{
-		lower: stack.FindLinkEndpoint(lower),
-	})
+func New(lower stack.LinkEndpoint) stack.LinkEndpoint {
+	return &endpoint{
+		lower: lower,
+	}
 }
 
 func zoneOffset() (int32, error) {
@@ -102,15 +102,15 @@ func writePCAPHeader(w io.Writer, maxLen uint32) error {
 // snapLen is the maximum amount of a packet to be saved. Packets with a length
 // less than or equal too snapLen will be saved in their entirety. Longer
 // packets will be truncated to snapLen.
-func NewWithFile(lower tcpip.LinkEndpointID, file *os.File, snapLen uint32) (tcpip.LinkEndpointID, error) {
+func NewWithFile(lower stack.LinkEndpoint, file *os.File, snapLen uint32) (stack.LinkEndpoint, error) {
 	if err := writePCAPHeader(file, snapLen); err != nil {
-		return 0, err
+		return nil, err
 	}
-	return stack.RegisterLinkEndpoint(&endpoint{
-		lower:      stack.FindLinkEndpoint(lower),
+	return &endpoint{
+		lower:      lower,
 		file:       file,
 		maxPCAPLen: snapLen,
-	}), nil
+	}, nil
 }
 
 // DeliverNetworkPacket implements the stack.NetworkDispatcher interface. It is
diff --git a/pkg/tcpip/link/waitable/waitable.go b/pkg/tcpip/link/waitable/waitable.go
index 3b6ac2ff7..408cc62f7 100644
--- a/pkg/tcpip/link/waitable/waitable.go
+++ b/pkg/tcpip/link/waitable/waitable.go
@@ -40,11 +40,10 @@ type Endpoint struct {
 // New creates a new waitable link-layer endpoint. It wraps around another
 // endpoint and allows the caller to block new write/dispatch calls and wait for
 // the inflight ones to finish before returning.
-func New(lower tcpip.LinkEndpointID) (tcpip.LinkEndpointID, *Endpoint) {
-	e := &Endpoint{
-		lower: stack.FindLinkEndpoint(lower),
+func New(lower stack.LinkEndpoint) *Endpoint {
+	return &Endpoint{
+		lower: lower,
 	}
-	return stack.RegisterLinkEndpoint(e), e
 }
 
 // DeliverNetworkPacket implements stack.NetworkDispatcher.DeliverNetworkPacket.
diff --git a/pkg/tcpip/link/waitable/waitable_test.go b/pkg/tcpip/link/waitable/waitable_test.go
index 56e18ecb0..1031438b1 100644
--- a/pkg/tcpip/link/waitable/waitable_test.go
+++ b/pkg/tcpip/link/waitable/waitable_test.go
@@ -72,7 +72,7 @@ func (e *countedEndpoint) WritePacket(r *stack.Route, _ *stack.GSO, hdr buffer.P
 
 func TestWaitWrite(t *testing.T) {
 	ep := &countedEndpoint{}
-	_, wep := New(stack.RegisterLinkEndpoint(ep))
+	wep := New(ep)
 
 	// Write and check that it goes through.
 	wep.WritePacket(nil, nil /* gso */, buffer.Prependable{}, buffer.VectorisedView{}, 0)
@@ -97,7 +97,7 @@ func TestWaitWrite(t *testing.T) {
 
 func TestWaitDispatch(t *testing.T) {
 	ep := &countedEndpoint{}
-	_, wep := New(stack.RegisterLinkEndpoint(ep))
+	wep := New(ep)
 
 	// Check that attach happens.
 	wep.Attach(ep)
@@ -139,7 +139,7 @@ func TestOtherMethods(t *testing.T) {
 		hdrLen:       hdrLen,
 		linkAddr:     linkAddr,
 	}
-	_, wep := New(stack.RegisterLinkEndpoint(ep))
+	wep := New(ep)
 
 	if v := wep.MTU(); v != mtu {
 		t.Fatalf("Unexpected mtu: got=%v, want=%v", v, mtu)