2 * Copyright (c) 2011 Nicira, Inc.
3 * Copyright (c) 2012 Cisco Systems, Inc.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of version 2 of the GNU General Public
7 * License as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 #include <linux/version.h>
23 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
27 #include <linux/net.h>
28 #include <linux/rculist.h>
29 #include <linux/udp.h>
39 #define VXLAN_FLAGS 0x08000000 /* struct vxlanhdr.vx_flags required value. */
42 * struct vxlanhdr - VXLAN header
43 * @vx_flags: Must have the exact value %VXLAN_FLAGS.
44 * @vx_vni: VXLAN Network Identifier (VNI) in top 24 bits, low 8 bits zeroed.
51 #define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
53 static inline int vxlan_hdr_len(const struct ovs_key_ipv4_tunnel *tun_key)
59 * struct vxlan_port - Keeps track of open UDP ports
60 * @list: list element.
61 * @vport: vport for the tunnel.
62 * @socket: The socket created for this port number.
65 struct list_head list;
67 struct socket *vxlan_rcv_socket;
71 static LIST_HEAD(vxlan_ports);
73 static struct vxlan_port *vxlan_find_port(struct net *net, __be16 port)
75 struct vxlan_port *vxlan_port;
77 list_for_each_entry_rcu(vxlan_port, &vxlan_ports, list) {
78 struct tnl_vport *tnl_vport = tnl_vport_priv(vxlan_port->vport);
80 if (tnl_vport->dst_port == port &&
81 net_eq(sock_net(vxlan_port->vxlan_rcv_socket->sk), net))
88 static inline struct vxlanhdr *vxlan_hdr(const struct sk_buff *skb)
90 return (struct vxlanhdr *)(udp_hdr(skb) + 1);
93 static void vxlan_build_header(const struct vport *vport,
97 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
98 struct udphdr *udph = udp_hdr(skb);
99 struct vxlanhdr *vxh = (struct vxlanhdr *)(udph + 1);
100 const struct ovs_key_ipv4_tunnel *tun_key = OVS_CB(skb)->tun_key;
102 udph->dest = tnl_vport->dst_port;
103 udph->source = htons(ovs_tnl_get_src_port(skb));
105 udph->len = htons(skb->len - skb_transport_offset(skb));
107 vxh->vx_flags = htonl(VXLAN_FLAGS);
108 vxh->vx_vni = htonl(be64_to_cpu(tun_key->tun_id) << 8);
111 /* Called with rcu_read_lock and BH disabled. */
112 static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)
114 struct vxlan_port *vxlan_vport;
115 struct vxlanhdr *vxh;
117 struct ovs_key_ipv4_tunnel tun_key;
120 vxlan_vport = vxlan_find_port(dev_net(skb->dev), udp_hdr(skb)->dest);
121 if (unlikely(!vxlan_vport))
124 if (unlikely(!pskb_may_pull(skb, VXLAN_HLEN + ETH_HLEN)))
127 vxh = vxlan_hdr(skb);
128 if (unlikely(vxh->vx_flags != htonl(VXLAN_FLAGS) ||
129 vxh->vx_vni & htonl(0xff)))
132 __skb_pull(skb, VXLAN_HLEN);
133 skb_postpull_rcsum(skb, skb_transport_header(skb), VXLAN_HLEN + ETH_HLEN);
135 key = cpu_to_be64(ntohl(vxh->vx_vni) >> 8);
137 /* Save outer tunnel values */
139 tnl_tun_key_init(&tun_key, iph, key, OVS_TNL_F_KEY);
140 OVS_CB(skb)->tun_key = &tun_key;
142 ovs_tnl_rcv(vxlan_vport->vport, skb);
151 /* Random value. Irrelevant as long as it's not 0 since we set the handler. */
152 #define UDP_ENCAP_VXLAN 1
153 static int vxlan_socket_init(struct vxlan_port *vxlan_port, struct net *net)
156 struct sockaddr_in sin;
157 struct tnl_vport *tnl_vport = tnl_vport_priv(vxlan_port->vport);
159 err = sock_create_kern(AF_INET, SOCK_DGRAM, 0,
160 &vxlan_port->vxlan_rcv_socket);
164 /* release net ref. */
165 sk_change_net(vxlan_port->vxlan_rcv_socket->sk, net);
167 sin.sin_family = AF_INET;
168 sin.sin_addr.s_addr = htonl(INADDR_ANY);
169 sin.sin_port = tnl_vport->dst_port;
171 err = kernel_bind(vxlan_port->vxlan_rcv_socket, (struct sockaddr *)&sin,
172 sizeof(struct sockaddr_in));
176 udp_sk(vxlan_port->vxlan_rcv_socket->sk)->encap_type = UDP_ENCAP_VXLAN;
177 udp_sk(vxlan_port->vxlan_rcv_socket->sk)->encap_rcv = vxlan_rcv;
184 sk_release_kernel(vxlan_port->vxlan_rcv_socket->sk);
186 pr_warn("cannot register vxlan protocol handler\n");
190 static void free_port_rcu(struct rcu_head *rcu)
192 struct vxlan_port *vxlan_port = container_of(rcu,
193 struct vxlan_port, rcu);
198 static void vxlan_tunnel_release(struct vxlan_port *vxlan_port)
203 list_del_rcu(&vxlan_port->list);
205 sk_release_kernel(vxlan_port->vxlan_rcv_socket->sk);
206 call_rcu(&vxlan_port->rcu, free_port_rcu);
209 static int vxlan_tunnel_setup(struct net *net, struct vport *vport,
210 struct nlattr *options)
212 struct vxlan_port *vxlan_port;
213 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
223 a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
224 if (a && nla_len(a) == sizeof(u16)) {
225 dst_port = nla_get_u16(a);
227 /* Require destination port from userspace. */
232 /* Verify if we already have a socket created for this port */
233 vxlan_port = vxlan_find_port(net, htons(dst_port));
239 /* Add a new socket for this port */
240 vxlan_port = kzalloc(sizeof(struct vxlan_port), GFP_KERNEL);
246 tnl_vport->dst_port = htons(dst_port);
247 vxlan_port->vport = vport;
248 list_add_tail_rcu(&vxlan_port->list, &vxlan_ports);
250 err = vxlan_socket_init(vxlan_port, net);
257 list_del_rcu(&vxlan_port->list);
263 static int vxlan_get_options(const struct vport *vport, struct sk_buff *skb)
265 const struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
267 if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(tnl_vport->dst_port)))
272 static const struct tnl_ops ovs_vxlan_tnl_ops = {
273 .ipproto = IPPROTO_UDP,
274 .hdr_len = vxlan_hdr_len,
275 .build_header = vxlan_build_header,
278 static void vxlan_tnl_destroy(struct vport *vport)
280 struct vxlan_port *vxlan_port;
281 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
283 vxlan_port = vxlan_find_port(ovs_dp_get_net(vport->dp),
284 tnl_vport->dst_port);
286 vxlan_tunnel_release(vxlan_port);
287 ovs_tnl_destroy(vport);
290 static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
295 vport = ovs_tnl_create(parms, &ovs_vxlan_vport_ops, &ovs_vxlan_tnl_ops);
299 err = vxlan_tunnel_setup(ovs_dp_get_net(parms->dp), vport,
302 ovs_tnl_destroy(vport);
309 const struct vport_ops ovs_vxlan_vport_ops = {
310 .type = OVS_VPORT_TYPE_VXLAN,
311 .flags = VPORT_F_TUN_ID,
312 .create = vxlan_tnl_create,
313 .destroy = vxlan_tnl_destroy,
314 .get_name = ovs_tnl_get_name,
315 .get_options = vxlan_get_options,
316 .send = ovs_tnl_send,
319 #warning VXLAN tunneling will not be available on kernels before 2.6.26
320 #endif /* Linux kernel < 2.6.26 */