net: rtnetlink: add msg kind names

Add rtnl kind names instead of using raw values. We'll need to
check for DEL kind later to validate bulk flag support.
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/rtnetlink.h

@@ -13,6 +13,13 @@ enum rtnl_link_flags {
 	RTNL_FLAG_DOIT_UNLOCKED = 1,
 };
 
+enum rtnl_kinds {
+	RTNL_KIND_NEW,
+	RTNL_KIND_DEL,
+	RTNL_KIND_GET,
+	RTNL_KIND_SET
+};
+
 void rtnl_register(int protocol, int msgtype,
 		   rtnl_doit_func, rtnl_dumpit_func, unsigned int flags);
 int rtnl_register_module(struct module *owner, int protocol, int msgtype,

net/core/rtnetlink.c

@@ -5928,11 +5928,11 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 {
 	struct net *net = sock_net(skb->sk);
 	struct rtnl_link *link;
+	enum rtnl_kinds kind;
 	struct module *owner;
 	int err = -EOPNOTSUPP;
 	rtnl_doit_func doit;
 	unsigned int flags;
-	int kind;
 	int family;
 	int type;
 
@@ -5949,11 +5949,11 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
 	kind = type&3;
 
-	if (kind != 2 && !netlink_net_capable(skb, CAP_NET_ADMIN))
+	if (kind != RTNL_KIND_GET && !netlink_net_capable(skb, CAP_NET_ADMIN))
 		return -EPERM;
 
 	rcu_read_lock();
-	if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
+	if (kind == RTNL_KIND_GET && (nlh->nlmsg_flags & NLM_F_DUMP)) {
 		struct sock *rtnl;
 		rtnl_dumpit_func dumpit;
 		u32 min_dump_alloc = 0;