net/openvswitch/vport-vxlan.c

   1 /*
   2  * Copyright (c) 2014 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/in.h>
  23 #include <linux/ip.h>
  24 #include <linux/net.h>
  25 #include <linux/rculist.h>
  26 #include <linux/udp.h>
  27 #include <linux/module.h>
  28
  29 #include <net/icmp.h>
  30 #include <net/ip.h>
  31 #include <net/udp.h>
  32 #include <net/ip_tunnels.h>
  33 #include <net/rtnetlink.h>
  34 #include <net/route.h>
  35 #include <net/dsfield.h>
  36 #include <net/inet_ecn.h>
  37 #include <net/net_namespace.h>
  38 #include <net/netns/generic.h>
  39 #include <net/vxlan.h>
  40
  41 #include "datapath.h"
  42 #include "vport.h"
  43
  44 /**
  45  * struct vxlan_port - Keeps track of open UDP ports
  46  * @vs: vxlan_sock created for the port.
  47  * @name: vport name.
  48  */
  49 struct vxlan_port {
  50         struct vxlan_sock *vs;
  51         char name[IFNAMSIZ];
  52 };
  53
  54 static struct vport_ops ovs_vxlan_vport_ops;
  55
  56 static inline struct vxlan_port *vxlan_vport(const struct vport *vport)
  57 {
  58         return vport_priv(vport);
  59 }
  60
  61 /* Called with rcu_read_lock and BH disabled. */
  62 static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb, __be32 vx_vni)
  63 {
  64         struct ovs_tunnel_info tun_info;
  65         struct vport *vport = vs->data;
  66         struct iphdr *iph;
  67         __be64 key;
  68
  69         /* Save outer tunnel values */
  70         iph = ip_hdr(skb);
  71         key = cpu_to_be64(ntohl(vx_vni) >> 8);
  72         ovs_flow_tun_info_init(&tun_info, iph,
  73                                udp_hdr(skb)->source, udp_hdr(skb)->dest,
  74                                key, TUNNEL_KEY, NULL, 0);
  75
  76         ovs_vport_receive(vport, skb, &tun_info);
  77 }
  78
  79 static int vxlan_get_options(const struct vport *vport, struct sk_buff *skb)
  80 {
  81         struct vxlan_port *vxlan_port = vxlan_vport(vport);
  82         __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
  83
  84         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
  85                 return -EMSGSIZE;
  86         return 0;
  87 }
  88
  89 static void vxlan_tnl_destroy(struct vport *vport)
  90 {
  91         struct vxlan_port *vxlan_port = vxlan_vport(vport);
  92
  93         vxlan_sock_release(vxlan_port->vs);
  94
  95         ovs_vport_deferred_free(vport);
  96 }
  97
  98 static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
  99 {
 100         struct net *net = ovs_dp_get_net(parms->dp);
 101         struct nlattr *options = parms->options;
 102         struct vxlan_port *vxlan_port;
 103         struct vxlan_sock *vs;
 104         struct vport *vport;
 105         struct nlattr *a;
 106         u16 dst_port;
 107         int err;
 108
 109         if (!options) {
 110                 err = -EINVAL;
 111                 goto error;
 112         }
 113         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 114         if (a && nla_len(a) == sizeof(u16)) {
 115                 dst_port = nla_get_u16(a);
 116         } else {
 117                 /* Require destination port from userspace. */
 118                 err = -EINVAL;
 119                 goto error;
 120         }
 121
 122         vport = ovs_vport_alloc(sizeof(struct vxlan_port),
 123                                 &ovs_vxlan_vport_ops, parms);
 124         if (IS_ERR(vport))
 125                 return vport;
 126
 127         vxlan_port = vxlan_vport(vport);
 128         strncpy(vxlan_port->name, parms->name, IFNAMSIZ);
 129
 130         vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true, 0);
 131         if (IS_ERR(vs)) {
 132                 ovs_vport_free(vport);
 133                 return (void *)vs;
 134         }
 135         vxlan_port->vs = vs;
 136
 137         return vport;
 138
 139 error:
 140         return ERR_PTR(err);
 141 }
 142
 143 static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 144 {
 145         struct net *net = ovs_dp_get_net(vport->dp);
 146         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 147         __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
 148         struct ovs_key_ipv4_tunnel *tun_key;
 149         struct rtable *rt;
 150         struct flowi4 fl;
 151         __be16 src_port;
 152         __be16 df;
 153         int err;
 154
 155         if (unlikely(!OVS_CB(skb)->egress_tun_info)) {
 156                 err = -EINVAL;
 157                 goto error;
 158         }
 159
 160         tun_key = &OVS_CB(skb)->egress_tun_info->tunnel;
 161         /* Route lookup */
 162         memset(&fl, 0, sizeof(fl));
 163         fl.daddr = tun_key->ipv4_dst;
 164         fl.saddr = tun_key->ipv4_src;
 165         fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
 166         fl.flowi4_mark = skb->mark;
 167         fl.flowi4_proto = IPPROTO_UDP;
 168
 169         rt = ip_route_output_key(net, &fl);
 170         if (IS_ERR(rt)) {
 171                 err = PTR_ERR(rt);
 172                 goto error;
 173         }
 174
 175         df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ?
 176                 htons(IP_DF) : 0;
 177
 178         skb->ignore_df = 1;
 179
 180         src_port = udp_flow_src_port(net, skb, 0, 0, true);
 181
 182         err = vxlan_xmit_skb(vxlan_port->vs, rt, skb,
 183                              fl.saddr, tun_key->ipv4_dst,
 184                              tun_key->ipv4_tos, tun_key->ipv4_ttl, df,
 185                              src_port, dst_port,
 186                              htonl(be64_to_cpu(tun_key->tun_id) << 8),
 187                              false);
 188         if (err < 0)
 189                 ip_rt_put(rt);
 190 error:
 191         return err;
 192 }
 193
 194 static int vxlan_get_egress_tun_info(struct vport *vport, struct sk_buff *skb,
 195                                      struct ovs_tunnel_info *egress_tun_info)
 196 {
 197         struct net *net = ovs_dp_get_net(vport->dp);
 198         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 199         __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
 200         __be16 src_port;
 201         int port_min;
 202         int port_max;
 203
 204         inet_get_local_port_range(net, &port_min, &port_max);
 205         src_port = udp_flow_src_port(net, skb, 0, 0, true);
 206
 207         return ovs_tunnel_get_egress_info(egress_tun_info, net,
 208                                           OVS_CB(skb)->egress_tun_info,
 209                                           IPPROTO_UDP, skb->mark,
 210                                           src_port, dst_port);
 211 }
 212
 213 static const char *vxlan_get_name(const struct vport *vport)
 214 {
 215         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 216         return vxlan_port->name;
 217 }
 218
 219 static struct vport_ops ovs_vxlan_vport_ops = {
 220         .type           = OVS_VPORT_TYPE_VXLAN,
 221         .create         = vxlan_tnl_create,
 222         .destroy        = vxlan_tnl_destroy,
 223         .get_name       = vxlan_get_name,
 224         .get_options    = vxlan_get_options,
 225         .send           = vxlan_tnl_send,
 226         .get_egress_tun_info    = vxlan_get_egress_tun_info,
 227         .owner          = THIS_MODULE,
 228 };
 229
 230 static int __init ovs_vxlan_tnl_init(void)
 231 {
 232         return ovs_vport_ops_register(&ovs_vxlan_vport_ops);
 233 }
 234
 235 static void __exit ovs_vxlan_tnl_exit(void)
 236 {
 237         ovs_vport_ops_unregister(&ovs_vxlan_vport_ops);
 238 }
 239
 240 module_init(ovs_vxlan_tnl_init);
 241 module_exit(ovs_vxlan_tnl_exit);
 242
 243 MODULE_DESCRIPTION("OVS: VXLAN switching port");
 244 MODULE_LICENSE("GPL");
 245 MODULE_ALIAS("vport-type-4");