[IPV6] Ensure to use interface hoplimit by default.

Signed-off-by: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>

include/net/addrconf.h

@@ -102,6 +102,8 @@ extern int ipv6_is_mld(struct sk_buff *skb, int nexthdr);
 
 extern void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len);
 
+extern int ipv6_get_hoplimit(struct net_device *dev);
+
 /*
  *	anycast prototypes (anycast.c)
  */

net/ipv6/icmp.c

@@ -381,6 +381,8 @@ void icmpv6_send(struct sk_buff *skb, int type, int code, __u32 info,
 		hlimit = np->hop_limit;
 	if (hlimit < 0)
 		hlimit = dst_metric(dst, RTAX_HOPLIMIT);
+	if (hlimit < 0)
+		hlimit = ipv6_get_hoplimit(dst->dev);
 
 	msg.skb = skb;
 	msg.offset = skb->nh.raw - skb->data;
@@ -467,6 +469,8 @@ static void icmpv6_echo_reply(struct sk_buff *skb)
 		hlimit = np->hop_limit;
 	if (hlimit < 0)
 		hlimit = dst_metric(dst, RTAX_HOPLIMIT);
+	if (hlimit < 0)
+		hlimit = ipv6_get_hoplimit(dst->dev);
 
 	idev = in6_dev_get(skb->dev);
 

net/ipv6/ip6_output.c

@@ -253,6 +253,8 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
 		hlimit = np->hop_limit;
 	if (hlimit < 0)
 		hlimit = dst_metric(dst, RTAX_HOPLIMIT);
+	if (hlimit < 0)
+		hlimit = ipv6_get_hoplimit(dst->dev);
 
 	hdr->payload_len = htons(seg_len);
 	hdr->nexthdr = proto;

net/ipv6/ndisc.c

@@ -1128,8 +1128,11 @@ static void ndisc_router_discovery(struct sk_buff *skb)
 	if (rt)
 		rt->rt6i_expires = jiffies + (HZ * lifetime);
 
-	if (ra_msg->icmph.icmp6_hop_limit)
+	if (ra_msg->icmph.icmp6_hop_limit) {
 		in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
+		if (rt)
+			rt->u.dst.metrics[RTAX_HOPLIMIT-1] = ra_msg->icmph.icmp6_hop_limit;
+	}
 
 	/*
 	 *	Update Reachable Time and Retrans Timer

net/ipv6/raw.c

@@ -756,6 +756,8 @@ static int rawv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 			hlimit = np->hop_limit;
 		if (hlimit < 0)
 			hlimit = dst_metric(dst, RTAX_HOPLIMIT);
+		if (hlimit < 0)
+			hlimit = ipv6_get_hoplimit(dst->dev);
 	}
 
 	if (msg->msg_flags&MSG_CONFIRM)

net/ipv6/route.c

@@ -771,7 +771,7 @@ static int ipv6_get_mtu(struct net_device *dev)
 	return mtu;
 }
 
-static int ipv6_get_hoplimit(struct net_device *dev)
+int ipv6_get_hoplimit(struct net_device *dev)
 {
 	int hoplimit = ipv6_devconf.hop_limit;
 	struct inet6_dev *idev;
@@ -967,15 +967,8 @@ int ip6_route_add(struct in6_rtmsg *rtmsg, struct nlmsghdr *nlh, void *_rtattr)
 		}
 	}
 
-	if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0) {
-		if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr))
-			rt->u.dst.metrics[RTAX_HOPLIMIT-1] =
-				IPV6_DEFAULT_MCASTHOPS;
-		else
-			rt->u.dst.metrics[RTAX_HOPLIMIT-1] =
-				ipv6_get_hoplimit(dev);
-	}
-
+	if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0)
+		rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
 	if (!rt->u.dst.metrics[RTAX_MTU-1])
 		rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
 	if (!rt->u.dst.metrics[RTAX_ADVMSS-1])
@@ -1414,7 +1407,7 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
 	rt->rt6i_idev = idev;
 	rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
 	rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_pmtu(&rt->u.dst));
-	rt->u.dst.metrics[RTAX_HOPLIMIT-1] = ipv6_get_hoplimit(rt->rt6i_dev);
+	rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
 	rt->u.dst.obsolete = -1;
 
 	rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;

net/ipv6/udp.c

@@ -811,6 +811,8 @@ static int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 			hlimit = np->hop_limit;
 		if (hlimit < 0)
 			hlimit = dst_metric(dst, RTAX_HOPLIMIT);
+		if (hlimit < 0)
+			hlimit = ipv6_get_hoplimit(dst->dev);
 	}
 
 	if (msg->msg_flags&MSG_CONFIRM)