vxlan: Allow setting destination to unicast address.

This patch allows setting VXLAN destination to unicast address.
It allows that VXLAN can be used as peer-to-peer tunnel without
multicast.

v4: generalize struct vxlan_dev, "gaddr" is replaced with vxlan_rdst.
    "GROUP" attribute is replaced with "REMOTE".
    they are based by David Stevens's comments.

v3: move a new attribute REMOTE into the last of an enum list
    based by Stephen Hemminger's comments.

v2: use a new attribute REMOTE instead of GROUP based by
    Cong Wang's comments.

Signed-off-by: Atzm Watanabe <atzm@stratosphere.co.jp>
Acked-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 30 insertions, 43 deletions

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 97a306c9e65d..916a62149a12 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -105,10 +105,8 @@ struct vxlan_fdb {
 struct vxlan_dev {
         struct hlist_node hlist;
         struct net_device *dev;
-        __u32             vni;          /* virtual network id */
-        __be32            gaddr;        /* multicast group */
+        struct vxlan_rdst default_dst;  /* default destination */
         __be32            saddr;        /* source address */
-        unsigned int      link;         /* link to multicast over */
         __u16             port_min;     /* source port range */
         __u16             port_max;
         __u8              tos;          /* TOS override */
@@ -146,7 +144,7 @@ static struct vxlan_dev *vxlan_find_vni(struct net *net, u32 id)
         struct vxlan_dev *vxlan;
 
         hlist_for_each_entry_rcu(vxlan, vni_head(net, id), hlist) {
-                if (vxlan->vni == id)
+                if (vxlan->default_dst.remote_vni == id)
                         return vxlan;
         }
 
@@ -194,7 +192,7 @@ static int vxlan_fdb_info(struct sk_buff *skb, struct vxlan_dev *vxlan,
         if (rdst->remote_port && rdst->remote_port != vxlan_port &&
             nla_put_be16(skb, NDA_PORT, rdst->remote_port))
                 goto nla_put_failure;
-        if (rdst->remote_vni != vxlan->vni &&
+        if (rdst->remote_vni != vxlan->default_dst.remote_vni &&
             nla_put_be32(skb, NDA_VNI, rdst->remote_vni))
                 goto nla_put_failure;
         if (rdst->remote_ifindex &&
@@ -465,7 +463,7 @@ static int vxlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
                         return -EINVAL;
                 vni = nla_get_u32(tb[NDA_VNI]);
         } else
-                vni = vxlan->vni;
+                vni = vxlan->default_dst.remote_vni;
 
         if (tb[NDA_IFINDEX]) {
                 struct net_device *tdev;
@@ -570,7 +568,7 @@ static void vxlan_snoop(struct net_device *dev,
                 err = vxlan_fdb_create(vxlan, src_mac, src_ip,
                                        NUD_REACHABLE,
                                        NLM_F_EXCL|NLM_F_CREATE,
-                                       vxlan_port, vxlan->vni, 0);
+                                       vxlan_port, vxlan->default_dst.remote_vni, 0);
                 spin_unlock(&vxlan->hash_lock);
         }
 }
@@ -591,7 +589,7 @@ static bool vxlan_group_used(struct vxlan_net *vn,
                         if (!netif_running(vxlan->dev))
                                 continue;
 
-                        if (vxlan->gaddr == this->gaddr)
+                        if (vxlan->default_dst.remote_ip == this->default_dst.remote_ip)
                                 return true;
                 }
 
@@ -605,8 +603,8 @@ static int vxlan_join_group(struct net_device *dev)
         struct vxlan_net *vn = net_generic(dev_net(dev), vxlan_net_id);
         struct sock *sk = vn->sock->sk;
         struct ip_mreqn mreq = {
-                .imr_multiaddr.s_addr   = vxlan->gaddr,
-                .imr_ifindex            = vxlan->link,
+                .imr_multiaddr.s_addr   = vxlan->default_dst.remote_ip,
+                .imr_ifindex            = vxlan->default_dst.remote_ifindex,
         };
         int err;
 
@@ -633,8 +631,8 @@ static int vxlan_leave_group(struct net_device *dev)
         int err = 0;
         struct sock *sk = vn->sock->sk;
         struct ip_mreqn mreq = {
-                .imr_multiaddr.s_addr   = vxlan->gaddr,
-                .imr_ifindex            = vxlan->link,
+                .imr_multiaddr.s_addr   = vxlan->default_dst.remote_ip,
+                .imr_ifindex            = vxlan->default_dst.remote_ifindex,
         };
 
         /* Only leave group when last vxlan is done. */
@@ -1091,7 +1089,7 @@ static netdev_tx_t vxlan_xmit(struct sk_buff *skb, struct net_device *dev)
         struct vxlan_dev *vxlan = netdev_priv(dev);
         struct ethhdr *eth;
         bool did_rsc = false;
-        struct vxlan_rdst group, *rdst0, *rdst;
+        struct vxlan_rdst *rdst0, *rdst;
         struct vxlan_fdb *f;
         int rc1, rc;
 
@@ -1106,14 +1104,9 @@ static netdev_tx_t vxlan_xmit(struct sk_buff *skb, struct net_device *dev)
         f = vxlan_find_mac(vxlan, eth->h_dest);
         if (f == NULL) {
                 did_rsc = false;
-                group.remote_port = vxlan_port;
-                group.remote_vni = vxlan->vni;
-                group.remote_ip = vxlan->gaddr;
-                group.remote_ifindex = vxlan->link;
-                group.remote_next = NULL;
-                rdst0 = &group;
-
-                if (group.remote_ip == htonl(INADDR_ANY) &&
+                rdst0 = &vxlan->default_dst;
+
+                if (rdst0->remote_ip == htonl(INADDR_ANY) &&
                     (vxlan->flags & VXLAN_F_L2MISS) &&
                     !is_multicast_ether_addr(eth->h_dest))
                         vxlan_fdb_miss(vxlan, eth->h_dest);
@@ -1191,7 +1184,7 @@ static int vxlan_open(struct net_device *dev)
         struct vxlan_dev *vxlan = netdev_priv(dev);
         int err;
 
-        if (vxlan->gaddr) {
+        if (IN_MULTICAST(ntohl(vxlan->default_dst.remote_ip))) {
                 err = vxlan_join_group(dev);
                 if (err)
                         return err;
@@ -1225,7 +1218,7 @@ static int vxlan_stop(struct net_device *dev)
 {
         struct vxlan_dev *vxlan = netdev_priv(dev);
 
-        if (vxlan->gaddr)
+        if (IN_MULTICAST(ntohl(vxlan->default_dst.remote_ip)))
                 vxlan_leave_group(dev);
 
         del_timer_sync(&vxlan->age_timer);
@@ -1311,7 +1304,7 @@ static void vxlan_setup(struct net_device *dev)
 
 static const struct nla_policy vxlan_policy[IFLA_VXLAN_MAX + 1] = {
         [IFLA_VXLAN_ID]         = { .type = NLA_U32 },
-        [IFLA_VXLAN_GROUP]      = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
+        [IFLA_VXLAN_REMOTE]     = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
         [IFLA_VXLAN_LINK]       = { .type = NLA_U32 },
         [IFLA_VXLAN_LOCAL]      = { .len = FIELD_SIZEOF(struct iphdr, saddr) },
         [IFLA_VXLAN_TOS]        = { .type = NLA_U8 },
@@ -1349,14 +1342,6 @@ static int vxlan_validate(struct nlattr *tb[], struct nlattr *data[])
                         return -ERANGE;
         }
 
-        if (data[IFLA_VXLAN_GROUP]) {
-                __be32 gaddr = nla_get_be32(data[IFLA_VXLAN_GROUP]);
-                if (!IN_MULTICAST(ntohl(gaddr))) {
-                        pr_debug("group address is not IPv4 multicast\n");
-                        return -EADDRNOTAVAIL;
-                }
-        }
-
         if (data[IFLA_VXLAN_PORT_RANGE]) {
                 const struct ifla_vxlan_port_range *p
                         = nla_data(data[IFLA_VXLAN_PORT_RANGE]);
@@ -1387,6 +1372,7 @@ static int vxlan_newlink(struct net *net, struct net_device *dev,
                          struct nlattr *tb[], struct nlattr *data[])
 {
         struct vxlan_dev *vxlan = netdev_priv(dev);
+        struct vxlan_rdst *dst = &vxlan->default_dst;
         __u32 vni;
         int err;
 
@@ -1398,21 +1384,21 @@ static int vxlan_newlink(struct net *net, struct net_device *dev,
                 pr_info("duplicate VNI %u\n", vni);
                 return -EEXIST;
         }
-        vxlan->vni = vni;
+        dst->remote_vni = vni;
 
-        if (data[IFLA_VXLAN_GROUP])
-                vxlan->gaddr = nla_get_be32(data[IFLA_VXLAN_GROUP]);
+        if (data[IFLA_VXLAN_REMOTE])
+                dst->remote_ip = nla_get_be32(data[IFLA_VXLAN_REMOTE]);
 
         if (data[IFLA_VXLAN_LOCAL])
                 vxlan->saddr = nla_get_be32(data[IFLA_VXLAN_LOCAL]);
 
         if (data[IFLA_VXLAN_LINK] &&
-            (vxlan->link = nla_get_u32(data[IFLA_VXLAN_LINK]))) {
+            (dst->remote_ifindex = nla_get_u32(data[IFLA_VXLAN_LINK]))) {
                 struct net_device *lowerdev
-                         = __dev_get_by_index(net, vxlan->link);
+                         = __dev_get_by_index(net, dst->remote_ifindex);
 
                 if (!lowerdev) {
-                        pr_info("ifindex %d does not exist\n", vxlan->link);
+                        pr_info("ifindex %d does not exist\n", dst->remote_ifindex);
                         return -ENODEV;
                 }
 
@@ -1464,7 +1450,7 @@ static int vxlan_newlink(struct net *net, struct net_device *dev,
 
         err = register_netdevice(dev);
         if (!err)
-                hlist_add_head_rcu(&vxlan->hlist, vni_head(net, vxlan->vni));
+                hlist_add_head_rcu(&vxlan->hlist, vni_head(net, dst->remote_vni));
 
         return err;
 }
@@ -1482,7 +1468,7 @@ static size_t vxlan_get_size(const struct net_device *dev)
 {
 
         return nla_total_size(sizeof(__u32)) +  /* IFLA_VXLAN_ID */
-                nla_total_size(sizeof(__be32)) +/* IFLA_VXLAN_GROUP */
+                nla_total_size(sizeof(__be32)) +/* IFLA_VXLAN_REMOTE */
                 nla_total_size(sizeof(__u32)) + /* IFLA_VXLAN_LINK */
                 nla_total_size(sizeof(__be32))+ /* IFLA_VXLAN_LOCAL */
                 nla_total_size(sizeof(__u8)) +  /* IFLA_VXLAN_TTL */
@@ -1501,18 +1487,19 @@ static size_t vxlan_get_size(const struct net_device *dev)
 static int vxlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
 {
         const struct vxlan_dev *vxlan = netdev_priv(dev);
+        const struct vxlan_rdst *dst = &vxlan->default_dst;
         struct ifla_vxlan_port_range ports = {
                 .low =  htons(vxlan->port_min),
                 .high = htons(vxlan->port_max),
         };
 
-        if (nla_put_u32(skb, IFLA_VXLAN_ID, vxlan->vni))
+        if (nla_put_u32(skb, IFLA_VXLAN_ID, dst->remote_vni))
                 goto nla_put_failure;
 
-        if (vxlan->gaddr && nla_put_be32(skb, IFLA_VXLAN_GROUP, vxlan->gaddr))
+        if (dst->remote_ip && nla_put_be32(skb, IFLA_VXLAN_REMOTE, dst->remote_ip))
                 goto nla_put_failure;
 
-        if (vxlan->link && nla_put_u32(skb, IFLA_VXLAN_LINK, vxlan->link))
+        if (dst->remote_ifindex && nla_put_u32(skb, IFLA_VXLAN_LINK, dst->remote_ifindex))
                 goto nla_put_failure;
 
         if (vxlan->saddr && nla_put_be32(skb, IFLA_VXLAN_LOCAL, vxlan->saddr))