net: Replace nhc_has_gw with nhc_gw_family

Allow the gateway in a fib_nh_common to be from a different address
family than the outer fib{6}_nh. To that end, replace nhc_has_gw with
nhc_gw_family and update users of nhc_has_gw to check nhc_gw_family.
Now nhc_family is used to know if the nh_common is part of a fib_nh
or fib6_nh (used for container_of to get to route family specific data),
and nhc_gw_family represents the address family for the gateway.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 27 insertions, 29 deletions

diff --git a/net/core/filter.c b/net/core/filter.c
index 26d9cd785ae2..abd5b6ce031a 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4639,7 +4639,7 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
 
 	dev = nhc->nhc_dev;
-	if (nhc->nhc_has_gw)
+	if (nhc->nhc_gw_family)
 		params->ipv4_dst = nhc->nhc_gw.ipv4;
 
 	params->rt_metric = res.fi->fib_priority;
@@ -4752,7 +4752,7 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 	if (f6i->fib6_nh.fib_nh_lws)
 		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
 
-	if (f6i->fib6_nh.fib_nh_has_gw)
+	if (f6i->fib6_nh.fib_nh_gw_family)
 		*dst = f6i->fib6_nh.fib_nh_gw6;
 
 	dev = f6i->fib6_nh.fib_nh_dev;
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 8e0cb1687a74..e11f78c6373f 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -513,7 +513,7 @@ int fib_nh_init(struct net *net, struct fib_nh *nh,
 	nh->fib_nh_oif = cfg->fc_oif;
 	if (cfg->fc_gw) {
 		nh->fib_nh_gw4 = cfg->fc_gw;
-		nh->fib_nh_has_gw = 1;
+		nh->fib_nh_gw_family = AF_INET;
 	}
 	nh->fib_nh_flags = cfg->fc_flags;
 
@@ -1238,7 +1238,7 @@ struct fib_info *fib_create_info(struct fib_config *cfg,
 				       "Route with host scope can not have multiple nexthops");
 			goto err_inval;
 		}
-		if (nh->fib_nh_gw4) {
+		if (nh->fib_nh_gw_family) {
 			NL_SET_ERR_MSG(extack,
 				       "Route with host scope can not have a gateway");
 			goto err_inval;
@@ -1341,18 +1341,15 @@ int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nhc,
 		rcu_read_unlock();
 	}
 
-	if (nhc->nhc_has_gw) {
-		switch (nhc->nhc_family) {
-		case AF_INET:
-			if (nla_put_in_addr(skb, RTA_GATEWAY, nhc->nhc_gw.ipv4))
-				goto nla_put_failure;
-			break;
-		case AF_INET6:
-			if (nla_put_in6_addr(skb, RTA_GATEWAY,
-					     &nhc->nhc_gw.ipv6) < 0)
-				goto nla_put_failure;
-			break;
-		}
+	switch (nhc->nhc_gw_family) {
+	case AF_INET:
+		if (nla_put_in_addr(skb, RTA_GATEWAY, nhc->nhc_gw.ipv4))
+			goto nla_put_failure;
+		break;
+	case AF_INET6:
+		if (nla_put_in6_addr(skb, RTA_GATEWAY, &nhc->nhc_gw.ipv6) < 0)
+			goto nla_put_failure;
+		break;
 	}
 
 	*flags |= (nhc->nhc_flags & RTNH_F_ONLINK);
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index f3f2adf630d4..e7338e421796 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1734,8 +1734,9 @@ static int __mkroute_input(struct sk_buff *skb,
 	do_cache = res->fi && !itag;
 	if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) &&
 	    skb->protocol == htons(ETH_P_IP)) {
-		__be32 gw = nhc->nhc_family == AF_INET ? nhc->nhc_gw.ipv4 : 0;
+		__be32 gw;
 
+		gw = nhc->nhc_gw_family == AF_INET ? nhc->nhc_gw.ipv4 : 0;
 		if (IN_DEV_SHARED_MEDIA(out_dev) ||
 		    inet_addr_onlink(out_dev, saddr, gw))
 			IPCB(skb)->flags |= IPSKB_DOREDIRECT;
@@ -2284,7 +2285,7 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
 		} else {
 			if (unlikely(fl4->flowi4_flags &
 				     FLOWI_FLAG_KNOWN_NH &&
-				     !(nhc->nhc_has_gw &&
+				     !(nhc->nhc_gw_family &&
 				       nhc->nhc_scope == RT_SCOPE_LINK))) {
 				do_cache = false;
 				goto add;
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 2e8d1d2d8d3d..340a0f06f974 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2421,7 +2421,7 @@ static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
 	for_each_fib6_node_rt_rcu(fn) {
 		if (rt->fib6_nh.fib_nh_dev->ifindex != dev->ifindex)
 			continue;
-		if (no_gw && rt->fib6_nh.fib_nh_has_gw)
+		if (no_gw && rt->fib6_nh.fib_nh_gw_family)
 			continue;
 		if ((rt->fib6_flags & flags) != flags)
 			continue;
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 8c00609a1513..46f54a5bb1f0 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -2304,7 +2304,7 @@ static int ipv6_route_seq_show(struct seq_file *seq, void *v)
 #else
 	seq_puts(seq, "00000000000000000000000000000000 00 ");
 #endif
-	if (rt->fib6_nh.fib_nh_has_gw) {
+	if (rt->fib6_nh.fib_nh_gw_family) {
 		flags |= RTF_GATEWAY;
 		seq_printf(seq, "%pi6", &rt->fib6_nh.fib_nh_gw6);
 	} else {
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 6e89151693d0..69f92d2b780e 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -533,7 +533,7 @@ static void rt6_probe(struct fib6_info *rt)
 	 * Router Reachability Probe MUST be rate-limited
 	 * to no more than one per minute.
 	 */
-	if (!rt || !rt->fib6_nh.fib_nh_has_gw)
+	if (!rt || !rt->fib6_nh.fib_nh_gw_family)
 		return;
 
 	nh_gw = &rt->fib6_nh.fib_nh_gw6;
@@ -595,7 +595,7 @@ static inline enum rt6_nud_state rt6_check_neigh(struct fib6_info *rt)
 	struct neighbour *neigh;
 
 	if (rt->fib6_flags & RTF_NONEXTHOP ||
-	    !rt->fib6_nh.fib_nh_has_gw)
+	    !rt->fib6_nh.fib_nh_gw_family)
 		return RT6_NUD_SUCCEED;
 
 	rcu_read_lock_bh();
@@ -769,7 +769,7 @@ static struct fib6_info *rt6_select(struct net *net, struct fib6_node *fn,
 
 static bool rt6_is_gw_or_nonexthop(const struct fib6_info *rt)
 {
-	return (rt->fib6_flags & RTF_NONEXTHOP) || rt->fib6_nh.fib_nh_has_gw;
+	return (rt->fib6_flags & RTF_NONEXTHOP) || rt->fib6_nh.fib_nh_gw_family;
 }
 
 #ifdef CONFIG_IPV6_ROUTE_INFO
@@ -975,7 +975,7 @@ static void ip6_rt_copy_init(struct rt6_info *rt, struct fib6_info *ort)
 	rt->rt6i_dst = ort->fib6_dst;
 	rt->rt6i_idev = dev ? in6_dev_get(dev) : NULL;
 	rt->rt6i_flags = ort->fib6_flags;
-	if (ort->fib6_nh.fib_nh_has_gw) {
+	if (ort->fib6_nh.fib_nh_gw_family) {
 		rt->rt6i_gateway = ort->fib6_nh.fib_nh_gw6;
 		rt->rt6i_flags |= RTF_GATEWAY;
 	}
@@ -1860,7 +1860,7 @@ struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
 		rcu_read_unlock();
 		return rt;
 	} else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
-			    !f6i->fib6_nh.fib_nh_has_gw)) {
+			    !f6i->fib6_nh.fib_nh_gw_family)) {
 		/* Create a RTF_CACHE clone which will not be
 		 * owned by the fib6 tree.  It is for the special case where
 		 * the daddr in the skb during the neighbor look-up is different
@@ -2430,7 +2430,7 @@ restart:
 			continue;
 		if (rt->fib6_flags & RTF_REJECT)
 			break;
-		if (!rt->fib6_nh.fib_nh_has_gw)
+		if (!rt->fib6_nh.fib_nh_gw_family)
 			continue;
 		if (fl6->flowi6_oif != rt->fib6_nh.fib_nh_dev->ifindex)
 			continue;
@@ -2964,7 +2964,7 @@ int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
 			goto out;
 
 		fib6_nh->fib_nh_gw6 = cfg->fc_gateway;
-		fib6_nh->fib_nh_has_gw = 1;
+		fib6_nh->fib_nh_gw_family = AF_INET6;
 	}
 
 	err = -ENODEV;
@@ -3476,7 +3476,7 @@ static struct fib6_info *rt6_get_route_info(struct net *net,
 		if (rt->fib6_nh.fib_nh_dev->ifindex != ifindex)
 			continue;
 		if (!(rt->fib6_flags & RTF_ROUTEINFO) ||
-		    !rt->fib6_nh.fib_nh_has_gw)
+		    !rt->fib6_nh.fib_nh_gw_family)
 			continue;
 		if (!ipv6_addr_equal(&rt->fib6_nh.fib_nh_gw6, gwaddr))
 			continue;
@@ -3807,7 +3807,7 @@ static int fib6_clean_tohost(struct fib6_info *rt, void *arg)
 	struct in6_addr *gateway = (struct in6_addr *)arg;
 
 	if (((rt->fib6_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) &&
-	    rt->fib6_nh.fib_nh_has_gw &&
+	    rt->fib6_nh.fib_nh_gw_family &&
 	    ipv6_addr_equal(gateway, &rt->fib6_nh.fib_nh_gw6)) {
 		return -1;
 	}