Add support for a subnet prefix length on interface network addresses

This allows the user code to add a network address with a subnet prefix length.
The prefix length value is stored in the network endpoint and provided back to
the user in the ProtocolAddress type.

PiperOrigin-RevId: 259807693

1 files changed, 7 insertions, 1 deletions

diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go
index 462265281..2037eef9f 100644
--- a/pkg/tcpip/stack/registration.go
+++ b/pkg/tcpip/stack/registration.go
@@ -181,6 +181,9 @@ type NetworkEndpoint interface {
 	// ID returns the network protocol endpoint ID.
 	ID() *NetworkEndpointID
 
+	// PrefixLen returns the network endpoint's subnet prefix length in bits.
+	PrefixLen() int
+
 	// NICID returns the id of the NIC this endpoint belongs to.
 	NICID() tcpip.NICID
 
@@ -203,12 +206,15 @@ type NetworkProtocol interface {
 	// than this targeted at this protocol.
 	MinimumPacketSize() int
 
+	// DefaultPrefixLen returns the protocol's default prefix length.
+	DefaultPrefixLen() int
+
 	// ParsePorts returns the source and destination addresses stored in a
 	// packet of this protocol.
 	ParseAddresses(v buffer.View) (src, dst tcpip.Address)
 
 	// NewEndpoint creates a new endpoint of this protocol.
-	NewEndpoint(nicid tcpip.NICID, addr tcpip.Address, linkAddrCache LinkAddressCache, dispatcher TransportDispatcher, sender LinkEndpoint) (NetworkEndpoint, *tcpip.Error)
+	NewEndpoint(nicid tcpip.NICID, addrWithPrefix tcpip.AddressWithPrefix, linkAddrCache LinkAddressCache, dispatcher TransportDispatcher, sender LinkEndpoint) (NetworkEndpoint, *tcpip.Error)
 
 	// SetOption allows enabling/disabling protocol specific features.
 	// SetOption returns an error if the option is not supported or the