1 files changed, 67 insertions, 49 deletions

diff --git a/src/pkg/net/multicast_test.go b/src/pkg/net/multicast_test.go
index be6dbf2dc..a66250c84 100644
--- a/src/pkg/net/multicast_test.go
+++ b/src/pkg/net/multicast_test.go
@@ -6,13 +6,33 @@ package net
 
 import (
 	"flag"
+	"os"
 	"runtime"
 	"testing"
 )
 
 var multicast = flag.Bool("multicast", false, "enable multicast tests")
 
-func TestMulticastJoinAndLeave(t *testing.T) {
+var joinAndLeaveGroupUDPTests = []struct {
+	net   string
+	laddr IP
+	gaddr IP
+	flags Flags
+	ipv6  bool
+}{
+	// cf. RFC 4727: Experimental Values in IPv4, IPv6, ICMPv4, ICMPv6, UDP, and TCP Headers
+	{"udp", IPv4zero, IPv4(224, 0, 0, 254), (FlagUp | FlagLoopback), false},
+	{"udp4", IPv4zero, IPv4(224, 0, 0, 254), (FlagUp | FlagLoopback), false},
+	{"udp", IPv6unspecified, ParseIP("ff0e::114"), (FlagUp | FlagLoopback), true},
+	{"udp6", IPv6unspecified, ParseIP("ff01::114"), (FlagUp | FlagLoopback), true},
+	{"udp6", IPv6unspecified, ParseIP("ff02::114"), (FlagUp | FlagLoopback), true},
+	{"udp6", IPv6unspecified, ParseIP("ff04::114"), (FlagUp | FlagLoopback), true},
+	{"udp6", IPv6unspecified, ParseIP("ff05::114"), (FlagUp | FlagLoopback), true},
+	{"udp6", IPv6unspecified, ParseIP("ff08::114"), (FlagUp | FlagLoopback), true},
+	{"udp6", IPv6unspecified, ParseIP("ff0e::114"), (FlagUp | FlagLoopback), true},
+}
+
+func TestJoinAndLeaveGroupUDP(t *testing.T) {
 	if runtime.GOOS == "windows" {
 		return
 	}
@@ -21,53 +41,51 @@ func TestMulticastJoinAndLeave(t *testing.T) {
 		return
 	}
 
-	addr := &UDPAddr{
-		IP:   IPv4zero,
-		Port: 0,
-	}
-	// open a UDPConn
-	conn, err := ListenUDP("udp4", addr)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer conn.Close()
-
-	// try to join group
-	mcast := IPv4(224, 0, 0, 254)
-	err = conn.JoinGroup(mcast)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// try to leave group
-	err = conn.LeaveGroup(mcast)
-	if err != nil {
-		t.Fatal(err)
-	}
-}
-
-func TestJoinFailureWithIPv6Address(t *testing.T) {
-	if !*multicast {
-		t.Logf("test disabled; use --multicast to enable")
-		return
-	}
-	addr := &UDPAddr{
-		IP:   IPv4zero,
-		Port: 0,
-	}
-
-	// open a UDPConn
-	conn, err := ListenUDP("udp4", addr)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer conn.Close()
-
-	// try to join group
-	mcast := ParseIP("ff02::1")
-	err = conn.JoinGroup(mcast)
-	if err == nil {
-		t.Fatal("JoinGroup succeeded, should fail")
+	for _, tt := range joinAndLeaveGroupUDPTests {
+		var (
+			ifi   *Interface
+			found bool
+		)
+		if tt.ipv6 && (!supportsIPv6 || os.Getuid() != 0) {
+			continue
+		}
+		ift, err := Interfaces()
+		if err != nil {
+			t.Fatalf("Interfaces() failed: %v", err)
+		}
+		for _, x := range ift {
+			if x.Flags&tt.flags == tt.flags {
+				ifi = &x
+				break
+			}
+		}
+		if ifi == nil {
+			t.Logf("an appropriate multicast interface not found")
+			return
+		}
+		c, err := ListenUDP(tt.net, &UDPAddr{IP: tt.laddr})
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer c.Close()
+		if err := c.JoinGroup(ifi, tt.gaddr); err != nil {
+			t.Fatal(err)
+		}
+		ifmat, err := ifi.MulticastAddrs()
+		if err != nil {
+			t.Fatalf("MulticastAddrs() failed: %v", err)
+		}
+		for _, ifma := range ifmat {
+			if ifma.(*IPAddr).IP.Equal(tt.gaddr) {
+				found = true
+				break
+			}
+		}
+		if !found {
+			t.Fatalf("%q not found in RIB", tt.gaddr.String())
+		}
+		if err := c.LeaveGroup(ifi, tt.gaddr); err != nil {
+			t.Fatal(err)
+		}
 	}
-	t.Logf("%s", err)
 }