datapath/vport-vxlan.c

   1 /*
   2  * Copyright (c) 2013 Nicira, Inc.
   3  * Copyright (c) 2013 Cisco Systems, Inc.
   4  *
   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.
   8  *
   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.
  13  *
  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
  17  * 02110-1301, USA
  18  */
  19
  20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  21
  22 #include <linux/version.h>
  23
  24 #include <linux/in.h>
  25 #include <linux/ip.h>
  26 #include <linux/net.h>
  27 #include <linux/rculist.h>
  28 #include <linux/udp.h>
  29
  30 #include <net/icmp.h>
  31 #include <net/ip.h>
  32 #include <net/udp.h>
  33 #include <net/ip_tunnels.h>
  34 #include <net/rtnetlink.h>
  35 #include <net/route.h>
  36 #include <net/dsfield.h>
  37 #include <net/inet_ecn.h>
  38 #include <net/net_namespace.h>
  39 #include <net/netns/generic.h>
  40 #include <net/vxlan.h>
  41
  42 #include "datapath.h"
  43 #include "vport.h"
  44
  45 /**
  46  * struct vxlan_port - Keeps track of open UDP ports
  47  * @vs: vxlan_sock created for the port.
  48  * @name: vport name.
  49  */
  50 struct vxlan_port {
  51         struct vxlan_sock *vs;
  52         char name[IFNAMSIZ];
  53 };
  54
  55 static inline struct vxlan_port *vxlan_vport(const struct vport *vport)
  56 {
  57         return vport_priv(vport);
  58 }
  59
  60 /* Called with rcu_read_lock and BH disabled. */
  61 static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb, __be32 vx_vni)
  62 {
  63         struct ovs_key_ipv4_tunnel tun_key;
  64         struct vport *vport = vs->data;
  65         struct iphdr *iph;
  66         __be64 key;
  67
  68         /* Save outer tunnel values */
  69         iph = ip_hdr(skb);
  70         key = cpu_to_be64(ntohl(vx_vni) >> 8);
  71         ovs_flow_tun_key_init(&tun_key, iph, key, TUNNEL_KEY);
  72
  73         ovs_vport_receive(vport, skb, &tun_key);
  74 }
  75
  76 static int vxlan_get_options(const struct vport *vport, struct sk_buff *skb)
  77 {
  78         struct vxlan_port *vxlan_port = vxlan_vport(vport);
  79         __be16 dst_port = inet_sport(vxlan_port->vs->sock->sk);
  80
  81         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
  82                 return -EMSGSIZE;
  83         return 0;
  84 }
  85
  86 static void vxlan_tnl_destroy(struct vport *vport)
  87 {
  88         struct vxlan_port *vxlan_port = vxlan_vport(vport);
  89
  90         vxlan_sock_release(vxlan_port->vs);
  91
  92         ovs_vport_deferred_free(vport);
  93 }
  94
  95 static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
  96 {
  97         struct net *net = ovs_dp_get_net(parms->dp);
  98         struct nlattr *options = parms->options;
  99         struct vxlan_port *vxlan_port;
 100         struct vxlan_sock *vs;
 101         struct vport *vport;
 102         struct nlattr *a;
 103         u16 dst_port;
 104         int err;
 105
 106         if (!options) {
 107                 err = -EINVAL;
 108                 goto error;
 109         }
 110         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 111         if (a && nla_len(a) == sizeof(u16)) {
 112                 dst_port = nla_get_u16(a);
 113         } else {
 114                 /* Require destination port from userspace. */
 115                 err = -EINVAL;
 116                 goto error;
 117         }
 118
 119         vport = ovs_vport_alloc(sizeof(struct vxlan_port),
 120                                 &ovs_vxlan_vport_ops, parms);
 121         if (IS_ERR(vport))
 122                 return vport;
 123
 124         vxlan_port = vxlan_vport(vport);
 125         strncpy(vxlan_port->name, parms->name, IFNAMSIZ);
 126
 127         vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true, false);
 128         if (IS_ERR(vs)) {
 129                 ovs_vport_free(vport);
 130                 return (void *)vs;
 131         }
 132         vxlan_port->vs = vs;
 133
 134         return vport;
 135
 136 error:
 137         return ERR_PTR(err);
 138 }
 139
 140 static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 141 {
 142         struct net *net = ovs_dp_get_net(vport->dp);
 143         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 144         __be16 dst_port = inet_sport(vxlan_port->vs->sock->sk);
 145         struct rtable *rt;
 146         __be16 src_port;
 147         __be32 saddr;
 148         __be16 df;
 149         int port_min;
 150         int port_max;
 151         int err;
 152
 153         if (unlikely(!OVS_CB(skb)->tun_key)) {
 154                 err = -EINVAL;
 155                 goto error;
 156         }
 157
 158         /* Route lookup */
 159         saddr = OVS_CB(skb)->tun_key->ipv4_src;
 160         rt = find_route(ovs_dp_get_net(vport->dp),
 161                         &saddr,
 162                         OVS_CB(skb)->tun_key->ipv4_dst,
 163                         IPPROTO_UDP,
 164                         OVS_CB(skb)->tun_key->ipv4_tos,
 165                         skb->mark);
 166         if (IS_ERR(rt)) {
 167                 err = PTR_ERR(rt);
 168                 goto error;
 169         }
 170
 171         df = OVS_CB(skb)->tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ?
 172                 htons(IP_DF) : 0;
 173
 174         skb->local_df = 1;
 175
 176         inet_get_local_port_range(net, &port_min, &port_max);
 177         src_port = vxlan_src_port(port_min, port_max, skb);
 178
 179         err = vxlan_xmit_skb(vxlan_port->vs, rt, skb,
 180                              saddr, OVS_CB(skb)->tun_key->ipv4_dst,
 181                              OVS_CB(skb)->tun_key->ipv4_tos,
 182                              OVS_CB(skb)->tun_key->ipv4_ttl, df,
 183                              src_port, dst_port,
 184                              htonl(be64_to_cpu(OVS_CB(skb)->tun_key->tun_id) << 8));
 185         if (err < 0)
 186                 ip_rt_put(rt);
 187 error:
 188         return err;
 189 }
 190
 191 static const char *vxlan_get_name(const struct vport *vport)
 192 {
 193         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 194         return vxlan_port->name;
 195 }
 196
 197 const struct vport_ops ovs_vxlan_vport_ops = {
 198         .type           = OVS_VPORT_TYPE_VXLAN,
 199         .create         = vxlan_tnl_create,
 200         .destroy        = vxlan_tnl_destroy,
 201         .get_name       = vxlan_get_name,
 202         .get_options    = vxlan_get_options,
 203         .send           = vxlan_tnl_send,
 204 };