ipv4: Add support to rtable for ipv6 gateway

Add support for an IPv6 gateway to rtable. Since a gateway is either
IPv4 or IPv6, make it a union with rt_gw4 where rt_gw_family decides
which address is in use.

When dumping the route data, encode an ipv6 nexthop using RTA_VIA.

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

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
index 133a497..560a60e 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
@@ -318,6 +318,9 @@ mlxsw_sp_span_gretap4_route(const struct net_device *to_dev,
        *saddrp = fl4.saddr;
        if (rt->rt_gw_family == AF_INET)
                *daddrp = rt->rt_gw4;
+       /* can not offload if route has an IPv6 gateway */
+       else if (rt->rt_gw_family == AF_INET6)
+               dev = NULL;
 
 out:
        ip_rt_put(rt);

diff --git a/include/net/route.h b/include/net/route.h
index 96912b0..5d28a25 100644 (file)
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -60,7 +60,10 @@ struct rtable {
        int                     rt_iif;
 
        /* Info on neighbour */
-       __be32                  rt_gw4;
+       union {
+               __be32          rt_gw4;
+               struct in6_addr rt_gw6;
+       };
 
        /* Miscellaneous cached information */
        u32                     rt_mtu_locked:1,

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index b77b495..6e58acf 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1535,14 +1535,20 @@ static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
 
        if (fi) {
                struct fib_nh_common *nhc = FIB_RES_NHC(*res);
-               struct fib_nh *nh = container_of(nhc, struct fib_nh, nh_common);
+               struct fib_nh *nh;
 
-               if (nh->fib_nh_gw4 && nh->fib_nh_scope == RT_SCOPE_LINK) {
-                       rt->rt_gw4 = nh->fib_nh_gw4;
-                       rt->rt_gw_family = AF_INET;
+               if (nhc->nhc_gw_family && nhc->nhc_scope == RT_SCOPE_LINK) {
+                       rt->rt_gw_family = nhc->nhc_gw_family;
+                       /* only INET and INET6 are supported */
+                       if (likely(nhc->nhc_gw_family == AF_INET))
+                               rt->rt_gw4 = nhc->nhc_gw.ipv4;
+                       else
+                               rt->rt_gw6 = nhc->nhc_gw.ipv6;
                }
+
                ip_dst_init_metrics(&rt->dst, fi->fib_metrics);
 
+               nh = container_of(nhc, struct fib_nh, nh_common);
 #ifdef CONFIG_IP_ROUTE_CLASSID
                rt->dst.tclassid = nh->nh_tclassid;
 #endif
@@ -2600,6 +2606,8 @@ struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_or
                rt->rt_gw_family = ort->rt_gw_family;
                if (rt->rt_gw_family == AF_INET)
                        rt->rt_gw4 = ort->rt_gw4;
+               else if (rt->rt_gw_family == AF_INET6)
+                       rt->rt_gw6 = ort->rt_gw6;
 
                INIT_LIST_HEAD(&rt->rt_uncached);
        }
@@ -2679,8 +2687,21 @@ static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
                        goto nla_put_failure;
        }
        if (rt->rt_gw_family == AF_INET &&
-           nla_put_in_addr(skb, RTA_GATEWAY, rt->rt_gw4))
+           nla_put_in_addr(skb, RTA_GATEWAY, rt->rt_gw4)) {
                goto nla_put_failure;
+       } else if (rt->rt_gw_family == AF_INET6) {
+               int alen = sizeof(struct in6_addr);
+               struct nlattr *nla;
+               struct rtvia *via;
+
+               nla = nla_reserve(skb, RTA_VIA, alen + 2);
+               if (!nla)
+                       goto nla_put_failure;
+
+               via = nla_data(nla);
+               via->rtvia_family = AF_INET6;
+               memcpy(via->rtvia_addr, &rt->rt_gw6, alen);
+       }
 
        expires = rt->dst.expires;
        if (expires) {

diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index ee53a91..72d19b1 100644 (file)
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -100,6 +100,8 @@ static int xfrm4_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
        xdst->u.rt.rt_gw_family = rt->rt_gw_family;
        if (rt->rt_gw_family == AF_INET)
                xdst->u.rt.rt_gw4 = rt->rt_gw4;
+       else if (rt->rt_gw_family == AF_INET6)
+               xdst->u.rt.rt_gw6 = rt->rt_gw6;
        xdst->u.rt.rt_pmtu = rt->rt_pmtu;
        xdst->u.rt.rt_mtu_locked = rt->rt_mtu_locked;
        INIT_LIST_HEAD(&xdst->u.rt.rt_uncached);

diff --git a/net/mpls/mpls_iptunnel.c b/net/mpls/mpls_iptunnel.c
index 1f61b4e..2619c2f 100644 (file)
--- a/net/mpls/mpls_iptunnel.c
+++ b/net/mpls/mpls_iptunnel.c
@@ -141,8 +141,9 @@ static int mpls_xmit(struct sk_buff *skb)
                if (rt->rt_gw_family == AF_INET)
                        err = neigh_xmit(NEIGH_ARP_TABLE, out_dev, &rt->rt_gw4,
                                         skb);
-               else
-                       err = -EAFNOSUPPORT;
+               else if (rt->rt_gw_family == AF_INET6)
+                       err = neigh_xmit(NEIGH_ND_TABLE, out_dev, &rt->rt_gw6,
+                                        skb);
        } else if (rt6) {
                if (ipv6_addr_v4mapped(&rt6->rt6i_gateway)) {
                        /* 6PE (RFC 4798) */