[netstack] Move SO_REUSEPORT and SO_REUSEADDR option to SocketOptions.

This changes also introduces:
- `SocketOptionsHandler` interface which can be implemented by endpoints to
  handle endpoint specific behavior on SetSockOpt. This is analogous to what
  Linux does.
- `DefaultSocketOptionsHandler` which is a default implementation of the above.
  This is embedded in all endpoints so that we don't have to uselessly
  implement empty functions. Endpoints with specific behavior can override the
  embedded method by manually defining its own implementation.

PiperOrigin-RevId: 343158301

1 files changed, 5 insertions, 2 deletions

diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go
index fe6514bcd..39560a9fa 100644
--- a/pkg/tcpip/transport/icmp/endpoint.go
+++ b/pkg/tcpip/transport/icmp/endpoint.go
@@ -49,6 +49,7 @@ const (
 // +stateify savable
 type endpoint struct {
 	stack.TransportEndpointInfo
+	tcpip.DefaultSocketOptionsHandler
 
 	// The following fields are initialized at creation time and are
 	// immutable.
@@ -85,7 +86,7 @@ type endpoint struct {
 }
 
 func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, transProto tcpip.TransportProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) {
-	return &endpoint{
+	ep := &endpoint{
 		stack: s,
 		TransportEndpointInfo: stack.TransportEndpointInfo{
 			NetProto:   netProto,
@@ -96,7 +97,9 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, transProt
 		sndBufSize:    32 * 1024,
 		state:         stateInitial,
 		uniqueID:      s.UniqueID(),
-	}, nil
+	}
+	ep.ops.InitHandler(ep)
+	return ep, nil
 }
 
 // UniqueID implements stack.TransportEndpoint.UniqueID.