From: Danny Mayer <mayer@ntp.org>
Date: Sun, 30 Nov 2003 01:52:42 +0000 (-0500)
Subject: Use scope id when address is link-local for IPv6 multicast IPV6_JOIN_GROUP
X-Git-Tag: NTP_4_2_3~193^2~3^2~2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=08e24c7f81c044dfc2155ead2bc3200086fa9076;p=thirdparty%2Fntp.git

Use scope id when address is link-local for IPv6 multicast IPV6_JOIN_GROUP

bk: 3fc94d6aeDBM8MbxsUuuq-JD-3qc3g
---

diff --git a/ntpd/ntp_io.c b/ntpd/ntp_io.c
index fd92cb0813..e7a820ba94 100644
--- a/ntpd/ntp_io.c
+++ b/ntpd/ntp_io.c
@@ -812,10 +812,17 @@ io_multicast_add(
 		}
 
 		/*
-		 * enable reception of multicast packets
+		 * Enable reception of multicast packets
+		 * If the address is link-local we can get the interface index
+		 * from the scope id. Don't do this for other types of multicast
+		 * addresses. For now let the kernel figure it out.
 		 */
 		mreq6.ipv6mr_multiaddr = iaddr6;
-		mreq6.ipv6mr_interface = inter_list[i].ifindex;
+		if (IN6_IS_ADDR_MC_LINKLOCAL(&iaddr6))
+			mreq6.ipv6mr_interface = sin6p->sin6_scope_id;
+		else
+			mreq6.ipv6mr_interface = 0;
+
 		if(setsockopt(inter_list[i].fd, IPPROTO_IPV6, IPV6_JOIN_GROUP,
 		   (char *)&mreq6, sizeof(mreq6)) == -1)
 			netsyslog(LOG_ERR,