Extract IGMPv2 core state machine

The IGMPv2 core state machine can be shared with MLDv1 since they are
almost identical, ignoring specific addresses, constants and packets.

Bug #4682, #4861

PiperOrigin-RevId: 344102615

1 files changed, 10 insertions, 0 deletions

diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go
index 3c7c5c0a8..40f6e8aa9 100644
--- a/pkg/tcpip/tcpip.go
+++ b/pkg/tcpip/tcpip.go
@@ -247,6 +247,16 @@ func (a Address) WithPrefix() AddressWithPrefix {
 	}
 }
 
+// Unspecified returns true if the address is unspecified.
+func (a Address) Unspecified() bool {
+	for _, b := range a {
+		if b != 0 {
+			return false
+		}
+	}
+	return true
+}
+
 // AddressMask is a bitmask for an address.
 type AddressMask string