net/openvswitch/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/in.h>
  23 #include <linux/ip.h>
  24 #include <linux/net.h>
  25 #include <linux/rculist.h>
  26 #include <linux/udp.h>
  27
  28 #include <net/icmp.h>
  29 #include <net/ip.h>
  30 #include <net/udp.h>
  31 #include <net/ip_tunnels.h>
  32 #include <net/udp.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 inline struct vxlan_port *vxlan_vport(const struct vport *vport)
  55 {
  56         return vport_priv(vport);
  57 }
  58
  59 /* Called with rcu_read_lock and BH disabled. */
  60 static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb, __be32 vx_vni)
  61 {
  62         struct ovs_key_ipv4_tunnel tun_key;
  63         struct vport *vport = vs->data;
  64         struct iphdr *iph;
  65         __be64 key;
  66
  67         /* Save outer tunnel values */
  68         iph = ip_hdr(skb);
  69         key = cpu_to_be64(ntohl(vx_vni) >> 8);
  70         ovs_flow_tun_key_init(&tun_key, iph, key, TUNNEL_KEY);
  71
  72         ovs_vport_receive(vport, skb, &tun_key);
  73 }
  74
  75 static int vxlan_get_options(const struct vport *vport, struct sk_buff *skb)
  76 {
  77         struct vxlan_port *vxlan_port = vxlan_vport(vport);
  78         __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
  79
  80         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
  81                 return -EMSGSIZE;
  82         return 0;
  83 }
  84
  85 static void vxlan_tnl_destroy(struct vport *vport)
  86 {
  87         struct vxlan_port *vxlan_port = vxlan_vport(vport);
  88
  89         vxlan_sock_release(vxlan_port->vs);
  90
  91         ovs_vport_deferred_free(vport);
  92 }
  93
  94 static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
  95 {
  96         struct net *net = ovs_dp_get_net(parms->dp);
  97         struct nlattr *options = parms->options;
  98         struct vxlan_port *vxlan_port;
  99         struct vxlan_sock *vs;
 100         struct vport *vport;
 101         struct nlattr *a;
 102         u16 dst_port;
 103         int err;
 104
 105         if (!options) {
 106                 err = -EINVAL;
 107                 goto error;
 108         }
 109         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 110         if (a && nla_len(a) == sizeof(u16)) {
 111                 dst_port = nla_get_u16(a);
 112         } else {
 113                 /* Require destination port from userspace. */
 114                 err = -EINVAL;
 115                 goto error;
 116         }
 117
 118         vport = ovs_vport_alloc(sizeof(struct vxlan_port),
 119                                 &ovs_vxlan_vport_ops, parms);
 120         if (IS_ERR(vport))
 121                 return vport;
 122
 123         vxlan_port = vxlan_vport(vport);
 124         strncpy(vxlan_port->name, parms->name, IFNAMSIZ);
 125
 126         vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true, false);
 127         if (IS_ERR(vs)) {
 128                 ovs_vport_free(vport);
 129                 return (void *)vs;
 130         }
 131         vxlan_port->vs = vs;
 132
 133         return vport;
 134
 135 error:
 136         return ERR_PTR(err);
 137 }
 138
 139 static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 140 {
 141         struct net *net = ovs_dp_get_net(vport->dp);
 142         struct vxlan_port *vxlan_port = vxlan_vport(vport);
 143         __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
 144         struct rtable *rt;
 145         struct flowi4 fl;
 146         __be16 src_port;
 147         int port_min;
 148         int port_max;
 149         __be16 df;
 150         int err;
 151
 152         if (unlikely(!OVS_CB(skb)->tun_key)) {
 153                 err = -EINVAL;
 154                 goto error;
 155         }
 156
 157         /* Route lookup */
 158         memset(&fl, 0, sizeof(fl));
 159         fl.daddr = OVS_CB(skb)->tun_key->ipv4_dst;
 160         fl.saddr = OVS_CB(skb)->tun_key->ipv4_src;
 161         fl.flowi4_tos = RT_TOS(OVS_CB(skb)->tun_key->ipv4_tos);
 162         fl.flowi4_mark = skb->mark;
 163         fl.flowi4_proto = IPPROTO_UDP;
 164
 165         rt = ip_route_output_key(net, &fl);
 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(&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                              fl.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 };