Change tcpip.Error to an interface

This makes it possible to add data to types that implement tcpip.Error.
ErrBadLinkEndpoint is removed as it is unused.

PiperOrigin-RevId: 354437314

4 files changed, 13 insertions, 13 deletions

diff --git a/pkg/tcpip/link/fdbased/endpoint.go b/pkg/tcpip/link/fdbased/endpoint.go
index f86c383d8..0164d851b 100644
--- a/pkg/tcpip/link/fdbased/endpoint.go
+++ b/pkg/tcpip/link/fdbased/endpoint.go
@@ -57,7 +57,7 @@ import (
 // linkDispatcher reads packets from the link FD and dispatches them to the
 // NetworkDispatcher.
 type linkDispatcher interface {
-	dispatch() (bool, *tcpip.Error)
+	dispatch() (bool, tcpip.Error)
 }
 
 // PacketDispatchMode are the various supported methods of receiving and
@@ -118,7 +118,7 @@ type endpoint struct {
 
 	// closed is a function to be called when the FD's peer (if any) closes
 	// its end of the communication pipe.
-	closed func(*tcpip.Error)
+	closed func(tcpip.Error)
 
 	inboundDispatchers []linkDispatcher
 	dispatcher         stack.NetworkDispatcher
@@ -149,7 +149,7 @@ type Options struct {
 
 	// ClosedFunc is a function to be called when an endpoint's peer (if
 	// any) closes its end of the communication pipe.
-	ClosedFunc func(*tcpip.Error)
+	ClosedFunc func(tcpip.Error)
 
 	// Address is the link address for this endpoint. Only used if
 	// EthernetHeader is true.
@@ -411,7 +411,7 @@ func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.Net
 
 // WritePacket writes outbound packets to the file descriptor. If it is not
 // currently writable, the packet is dropped.
-func (e *endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) tcpip.Error {
 	if e.hdrSize > 0 {
 		e.AddHeader(r.LocalLinkAddress, r.RemoteLinkAddress, protocol, pkt)
 	}
@@ -451,7 +451,7 @@ func (e *endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip
 	return rawfile.NonBlockingWriteIovec(fd, builder.Build())
 }
 
-func (e *endpoint) sendBatch(batchFD int, batch []*stack.PacketBuffer) (int, *tcpip.Error) {
+func (e *endpoint) sendBatch(batchFD int, batch []*stack.PacketBuffer) (int, tcpip.Error) {
 	// Send a batch of packets through batchFD.
 	mmsgHdrs := make([]rawfile.MMsgHdr, 0, len(batch))
 	for _, pkt := range batch {
@@ -518,7 +518,7 @@ func (e *endpoint) sendBatch(batchFD int, batch []*stack.PacketBuffer) (int, *tc
 //  - pkt.EgressRoute
 //  - pkt.GSOOptions
 //  - pkt.NetworkProtocolNumber
-func (e *endpoint) WritePackets(_ stack.RouteInfo, _ *stack.GSO, pkts stack.PacketBufferList, _ tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *endpoint) WritePackets(_ stack.RouteInfo, _ *stack.GSO, pkts stack.PacketBufferList, _ tcpip.NetworkProtocolNumber) (int, tcpip.Error) {
 	// Preallocate to avoid repeated reallocation as we append to batch.
 	// batchSz is 47 because when SWGSO is in use then a single 65KB TCP
 	// segment can get split into 46 segments of 1420 bytes and a single 216
@@ -562,13 +562,13 @@ func viewsEqual(vs1, vs2 []buffer.View) bool {
 }
 
 // InjectOutobund implements stack.InjectableEndpoint.InjectOutbound.
-func (e *endpoint) InjectOutbound(dest tcpip.Address, packet []byte) *tcpip.Error {
+func (e *endpoint) InjectOutbound(dest tcpip.Address, packet []byte) tcpip.Error {
 	return rawfile.NonBlockingWrite(e.fds[0], packet)
 }
 
 // dispatchLoop reads packets from the file descriptor in a loop and dispatches
 // them to the network stack.
-func (e *endpoint) dispatchLoop(inboundDispatcher linkDispatcher) *tcpip.Error {
+func (e *endpoint) dispatchLoop(inboundDispatcher linkDispatcher) tcpip.Error {
 	for {
 		cont, err := inboundDispatcher.dispatch()
 		if err != nil || !cont {
diff --git a/pkg/tcpip/link/fdbased/endpoint_test.go b/pkg/tcpip/link/fdbased/endpoint_test.go
index e2985cb84..e82371798 100644
--- a/pkg/tcpip/link/fdbased/endpoint_test.go
+++ b/pkg/tcpip/link/fdbased/endpoint_test.go
@@ -95,7 +95,7 @@ func newContext(t *testing.T, opt *Options) *context {
 	}
 
 	done := make(chan struct{}, 2)
-	opt.ClosedFunc = func(*tcpip.Error) {
+	opt.ClosedFunc = func(tcpip.Error) {
 		done <- struct{}{}
 	}
 
diff --git a/pkg/tcpip/link/fdbased/mmap.go b/pkg/tcpip/link/fdbased/mmap.go
index c475dda20..a2b63fe6b 100644
--- a/pkg/tcpip/link/fdbased/mmap.go
+++ b/pkg/tcpip/link/fdbased/mmap.go
@@ -129,7 +129,7 @@ type packetMMapDispatcher struct {
 	ringOffset int
 }
 
-func (d *packetMMapDispatcher) readMMappedPacket() ([]byte, *tcpip.Error) {
+func (d *packetMMapDispatcher) readMMappedPacket() ([]byte, tcpip.Error) {
 	hdr := tPacketHdr(d.ringBuffer[d.ringOffset*tpFrameSize:])
 	for hdr.tpStatus()&tpStatusUser == 0 {
 		event := rawfile.PollEvent{
@@ -163,7 +163,7 @@ func (d *packetMMapDispatcher) readMMappedPacket() ([]byte, *tcpip.Error) {
 
 // dispatch reads packets from an mmaped ring buffer and dispatches them to the
 // network stack.
-func (d *packetMMapDispatcher) dispatch() (bool, *tcpip.Error) {
+func (d *packetMMapDispatcher) dispatch() (bool, tcpip.Error) {
 	pkt, err := d.readMMappedPacket()
 	if err != nil {
 		return false, err
diff --git a/pkg/tcpip/link/fdbased/packet_dispatchers.go b/pkg/tcpip/link/fdbased/packet_dispatchers.go
index edab110b5..ecae1ad2d 100644
--- a/pkg/tcpip/link/fdbased/packet_dispatchers.go
+++ b/pkg/tcpip/link/fdbased/packet_dispatchers.go
@@ -139,7 +139,7 @@ func newReadVDispatcher(fd int, e *endpoint) (linkDispatcher, error) {
 }
 
 // dispatch reads one packet from the file descriptor and dispatches it.
-func (d *readVDispatcher) dispatch() (bool, *tcpip.Error) {
+func (d *readVDispatcher) dispatch() (bool, tcpip.Error) {
 	n, err := rawfile.BlockingReadv(d.fd, d.buf.nextIovecs())
 	if n == 0 || err != nil {
 		return false, err
@@ -226,7 +226,7 @@ func newRecvMMsgDispatcher(fd int, e *endpoint) (linkDispatcher, error) {
 
 // recvMMsgDispatch reads more than one packet at a time from the file
 // descriptor and dispatches it.
-func (d *recvMMsgDispatcher) dispatch() (bool, *tcpip.Error) {
+func (d *recvMMsgDispatcher) dispatch() (bool, tcpip.Error) {
 	// Fill message headers.
 	for k := range d.msgHdrs {
 		if d.msgHdrs[k].Msg.Iovlen > 0 {