net/netip: add IPv6LinkLocalAllRouters and IPv6Loopback

Fixes #51766
Fixes #51777

Change-Id: I0510175c20c06442d78b2581cfe218e66be1c35b
Reviewed-on: https://go-review.googlesource.com/c/go/+/412475
Auto-Submit: Brad Fitzpatrick <[email protected]>
Reviewed-by: David Chase <[email protected]>
Reviewed-by: Damien Neil <[email protected]>
Run-TryBot: Brad Fitzpatrick <[email protected]>
Reviewed-by: Tobias Klauser <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Run-TryBot: Matt Layher <[email protected]>
Reviewed-by: Brad Fitzpatrick <[email protected]>
Auto-Submit: Damien Neil <[email protected]>

Author: mdlayher

api/next/51766.txt

@@ -0,0 +1 @@
+pkg net/netip, func IPv6LinkLocalAllRouters() Addr #51766

api/next/51777.txt

@@ -0,0 +1 @@
+pkg net/netip, func IPv6Loopback() Addr #51777

src/net/netip/netip.go

@@ -75,6 +75,13 @@ var (
 // address ff02::1.
 func IPv6LinkLocalAllNodes() Addr { return AddrFrom16([16]byte{0: 0xff, 1: 0x02, 15: 0x01}) }
 
+// IPv6LinkLocalAllRouters returns the IPv6 link-local all routers multicast
+// address ff02::2.
+func IPv6LinkLocalAllRouters() Addr { return AddrFrom16([16]byte{0: 0xff, 1: 0x02, 15: 0x02}) }
+
+// IPv6Loopback returns the IPv6 loopback address ::1.
+func IPv6Loopback() Addr { return AddrFrom16([16]byte{15: 0x01}) }
+
 // IPv6Unspecified returns the IPv6 unspecified address "::".
 func IPv6Unspecified() Addr { return Addr{z: z6noz} }
 

src/net/netip/netip_test.go

@@ -784,6 +784,16 @@ func TestAddrWellKnown(t *testing.T) {
 			ip:   IPv6LinkLocalAllNodes(),
 			std:  net.IPv6linklocalallnodes,
 		},
+		{
+			name: "IPv6 link-local all routers",
+			ip:   IPv6LinkLocalAllRouters(),
+			std:  net.IPv6linklocalallrouters,
+		},
+		{
+			name: "IPv6 loopback",
+			ip:   IPv6Loopback(),
+			std:  net.IPv6loopback,
+		},
 		{
 			name: "IPv6 unspecified",
 			ip:   IPv6Unspecified(),
@@ -1867,6 +1877,8 @@ func TestNoAllocs(t *testing.T) {
 	test("ParseAddr/6", func() { sinkIP = panicIP(ParseAddr("::1")) })
 	test("MustParseAddr", func() { sinkIP = MustParseAddr("1.2.3.4") })
 	test("IPv6LinkLocalAllNodes", func() { sinkIP = IPv6LinkLocalAllNodes() })
+	test("IPv6LinkLocalAllRouters", func() { sinkIP = IPv6LinkLocalAllRouters() })
+	test("IPv6Loopback", func() { sinkIP = IPv6Loopback() })
 	test("IPv6Unspecified", func() { sinkIP = IPv6Unspecified() })
 
 	// IP methods