Automated rollback of changelist 268047073

PiperOrigin-RevId: 269658971

1 files changed, 25 insertions, 0 deletions

diff --git a/pkg/tcpip/header/ipv6.go b/pkg/tcpip/header/ipv6.go
index 093850e25..9d3abc0e4 100644
--- a/pkg/tcpip/header/ipv6.go
+++ b/pkg/tcpip/header/ipv6.go
@@ -76,6 +76,13 @@ const (
 	// IPv6Version is the version of the ipv6 protocol.
 	IPv6Version = 6
 
+	// IPv6AllNodesMulticastAddress is a link-local multicast group that
+	// all IPv6 nodes MUST join, as per RFC 4291, section 2.8. Packets
+	// destined to this address will reach all nodes on a link.
+	//
+	// The address is ff02::1.
+	IPv6AllNodesMulticastAddress tcpip.Address = "\xff\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01"
+
 	// IPv6MinimumMTU is the minimum MTU required by IPv6, per RFC 2460,
 	// section 5.
 	IPv6MinimumMTU = 1280
@@ -221,6 +228,24 @@ func IsV6MulticastAddress(addr tcpip.Address) bool {
 	return addr[0] == 0xff
 }
 
+// IsV6UnicastAddress determines if the provided address is a valid IPv6
+// unicast (and specified) address. That is, IsV6UnicastAddress returns
+// true if addr contains IPv6AddressSize bytes, is not the unspecified
+// address and is not a multicast address.
+func IsV6UnicastAddress(addr tcpip.Address) bool {
+	if len(addr) != IPv6AddressSize {
+		return false
+	}
+
+	// Must not be unspecified
+	if addr == IPv6Any {
+		return false
+	}
+
+	// Return if not a multicast.
+	return addr[0] != 0xff
+}
+
 // SolicitedNodeAddr computes the solicited-node multicast address. This is
 // used for NDP. Described in RFC 4291. The argument must be a full-length IPv6
 // address.