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,
  63                       struct vxlan_metadata *md)
  64 {
  65         struct ovs_tunnel_info tun_info;
  66         struct vport *vport = vs->data;
  67         struct iphdr *iph;
  68         __be64 key;
  69
  70         /* Save outer tunnel values */
  71         iph = ip_hdr(skb);
  72         key = cpu_to_be64(ntohl(md->vni) >> 8);
  73         ovs_flow_tun_info_init(&tun_info, iph,
  74                                udp_hdr(skb)->source, udp_hdr(skb)->dest,
  75                                key, TUNNEL_KEY, NULL, 0);
  76
  77         ovs_vport_receive(vport, skb, &tun_info);
  78 }
  79
  80 static int vxlan_get_options(const struct vport *vport, struct sk_buff *skb)
  81 {
  82         struct vxlan_port *vxlan_port = vxlan_vport(vport);
  83         __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
  84
  85         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
  86                 return -EMSGSIZE;
  87         return 0;
  88 }
  89
  90 static void vxlan_tnl_destroy(struct vport *vport)
  91 {
  92         struct vxlan_port *vxlan_port = vxlan_vport(vport);
  93
  94         vxlan_sock_release(vxlan_port->vs);
  95
  96         ovs_vport_deferred_free(vport);
  97 }
  98
  99 static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
 100 {
 101         struct net *net = ovs_dp_get_net(parms->dp);
 102         struct nlattr *options = parms->options;
 103         struct vxlan_port *vxlan_port;
 104         struct vxlan_sock *vs;
 105         struct vport *vport;
 106         struct nlattr *a;
 107         u16 dst_port;
 108         int err;
 109
 110         if (!options) {
 111                 err = -EINVAL;
 112                 goto error;
 113         }
 114         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 115         if (a && nla_len(a) == sizeof(u16)) {
 116                 dst_port = nla_get_u16(a);
 117         } else {
 118                 /* Require destination port from userspace. */
 119                 err = -EINVAL;
 120                 goto error;
 121         }
 122
 123         vport = ovs_vport_alloc(sizeof(struct vxlan_port),
 124                                 &ovs_vxlan_vport_ops, parms);
 125         if (IS_ERR(vport))
 126                 return vport;
 127
 128         vxlan_port = vxlan_vport(vport);
 129         strncpy(vxlan_port->name, parms->name, IFNAMSIZ);
 130
 131         vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true, 0);
 132         if (IS_ERR(vs)) {
 133                 ovs_vport_free(vport);
 134                 return (void *)vs;
 135         }
 136         vxlan_port->vs = vs;
 137
 138         return vport;
 139
 140 error:
 141         return ERR_PTR(err);
 142 }
 143
 144 static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 145 {
 146         struct net *net = ovs_dp_get_net(vport->dp);
 147         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 148         __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
 149         const struct ovs_key_ipv4_tunnel *tun_key;
 150         struct vxlan_metadata md = {0};
 151         struct rtable *rt;
 152         struct flowi4 fl;
 153         __be16 src_port;
 154         __be16 df;
 155         int err;
 156
 157         if (unlikely(!OVS_CB(skb)->egress_tun_info)) {
 158                 err = -EINVAL;
 159                 goto error;
 160         }
 161
 162         tun_key = &OVS_CB(skb)->egress_tun_info->tunnel;
 163         rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_UDP);
 164         if (IS_ERR(rt)) {
 165                 err = PTR_ERR(rt);
 166                 goto error;
 167         }
 168
 169         df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ?
 170                 htons(IP_DF) : 0;
 171
 172         skb->ignore_df = 1;
 173
 174         src_port = udp_flow_src_port(net, skb, 0, 0, true);
 175         md.vni = htonl(be64_to_cpu(tun_key->tun_id) << 8);
 176
 177         err = vxlan_xmit_skb(vxlan_port->vs, rt, skb,
 178                              fl.saddr, tun_key->ipv4_dst,
 179                              tun_key->ipv4_tos, tun_key->ipv4_ttl, df,
 180                              src_port, dst_port,
 181                              &md,
 182                              false);
 183         if (err < 0)
 184                 ip_rt_put(rt);
 185         return err;
 186 error:
 187         kfree_skb(skb);
 188         return err;
 189 }
 190
 191 static int vxlan_get_egress_tun_info(struct vport *vport, struct sk_buff *skb,
 192                                      struct ovs_tunnel_info *egress_tun_info)
 193 {
 194         struct net *net = ovs_dp_get_net(vport->dp);
 195         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 196         __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
 197         __be16 src_port;
 198         int port_min;
 199         int port_max;
 200
 201         inet_get_local_port_range(net, &port_min, &port_max);
 202         src_port = udp_flow_src_port(net, skb, 0, 0, true);
 203
 204         return ovs_tunnel_get_egress_info(egress_tun_info, net,
 205                                           OVS_CB(skb)->egress_tun_info,
 206                                           IPPROTO_UDP, skb->mark,
 207                                           src_port, dst_port);
 208 }
 209
 210 static const char *vxlan_get_name(const struct vport *vport)
 211 {
 212         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 213         return vxlan_port->name;
 214 }
 215
 216 static struct vport_ops ovs_vxlan_vport_ops = {
 217         .type           = OVS_VPORT_TYPE_VXLAN,
 218         .create         = vxlan_tnl_create,
 219         .destroy        = vxlan_tnl_destroy,
 220         .get_name       = vxlan_get_name,
 221         .get_options    = vxlan_get_options,
 222         .send           = vxlan_tnl_send,
 223         .get_egress_tun_info    = vxlan_get_egress_tun_info,
 224         .owner          = THIS_MODULE,
 225 };
 226
 227 static int __init ovs_vxlan_tnl_init(void)
 228 {
 229         return ovs_vport_ops_register(&ovs_vxlan_vport_ops);
 230 }
 231
 232 static void __exit ovs_vxlan_tnl_exit(void)
 233 {
 234         ovs_vport_ops_unregister(&ovs_vxlan_vport_ops);
 235 }
 236
 237 module_init(ovs_vxlan_tnl_init);
 238 module_exit(ovs_vxlan_tnl_exit);
 239
 240 MODULE_DESCRIPTION("OVS: VXLAN switching port");
 241 MODULE_LICENSE("GPL");
 242 MODULE_ALIAS("vport-type-4");