tipc: support 128bit node identity for peer removing

We add the support to remove a specific node down with 128bit
node identifier, as an alternative to legacy 32-bit node address.

example:
$tipc peer remove identiy <1001002|16777777>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Link: https://lore.kernel.org/r/20201203035045.4564-1-hoang.h.le@dektech.com.auSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/tipc/node.c

@@ -2222,6 +2222,9 @@ int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
 	struct tipc_node *peer, *temp_node;
+	u8 node_id[NODE_ID_LEN];
+	u64 *w0 = (u64 *)&node_id[0];
+	u64 *w1 = (u64 *)&node_id[8];
 	u32 addr;
 	int err;
 
@@ -2235,10 +2238,22 @@ int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
 	if (err)
 		return err;
 
-	if (!attrs[TIPC_NLA_NET_ADDR])
+	/* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
+	 * mutually exclusive cases
+	 */
+	if (attrs[TIPC_NLA_NET_ADDR]) {
+		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
+		if (!addr)
 			return -EINVAL;
+	}
 
-	addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
+	if (attrs[TIPC_NLA_NET_NODEID]) {
+		if (!attrs[TIPC_NLA_NET_NODEID_W1])
+			return -EINVAL;
+		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
+		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
+		addr = hash128to32(node_id);
+	}
 
 	if (in_own_node(net, addr))
 		return -ENOTSUPP;