net/openvswitch/vport-geneve.c

   1 /*
   2  * Copyright (c) 2014 Nicira, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/version.h>
  13
  14 #include <linux/in.h>
  15 #include <linux/ip.h>
  16 #include <linux/net.h>
  17 #include <linux/rculist.h>
  18 #include <linux/udp.h>
  19 #include <linux/if_vlan.h>
  20 #include <linux/module.h>
  21
  22 #include <net/geneve.h>
  23 #include <net/icmp.h>
  24 #include <net/ip.h>
  25 #include <net/route.h>
  26 #include <net/udp.h>
  27 #include <net/xfrm.h>
  28
  29 #include "datapath.h"
  30 #include "vport.h"
  31
  32 static struct vport_ops ovs_geneve_vport_ops;
  33
  34 /**
  35  * struct geneve_port - Keeps track of open UDP ports
  36  * @gs: The socket created for this port number.
  37  * @name: vport name.
  38  */
  39 struct geneve_port {
  40         struct geneve_sock *gs;
  41         char name[IFNAMSIZ];
  42 };
  43
  44 static LIST_HEAD(geneve_ports);
  45
  46 static inline struct geneve_port *geneve_vport(const struct vport *vport)
  47 {
  48         return vport_priv(vport);
  49 }
  50
  51 static inline struct genevehdr *geneve_hdr(const struct sk_buff *skb)
  52 {
  53         return (struct genevehdr *)(udp_hdr(skb) + 1);
  54 }
  55
  56 /* Convert 64 bit tunnel ID to 24 bit VNI. */
  57 static void tunnel_id_to_vni(__be64 tun_id, __u8 *vni)
  58 {
  59 #ifdef __BIG_ENDIAN
  60         vni[0] = (__force __u8)(tun_id >> 16);
  61         vni[1] = (__force __u8)(tun_id >> 8);
  62         vni[2] = (__force __u8)tun_id;
  63 #else
  64         vni[0] = (__force __u8)((__force u64)tun_id >> 40);
  65         vni[1] = (__force __u8)((__force u64)tun_id >> 48);
  66         vni[2] = (__force __u8)((__force u64)tun_id >> 56);
  67 #endif
  68 }
  69
  70 /* Convert 24 bit VNI to 64 bit tunnel ID. */
  71 static __be64 vni_to_tunnel_id(const __u8 *vni)
  72 {
  73 #ifdef __BIG_ENDIAN
  74         return (vni[0] << 16) | (vni[1] << 8) | vni[2];
  75 #else
  76         return (__force __be64)(((__force u64)vni[0] << 40) |
  77                                 ((__force u64)vni[1] << 48) |
  78                                 ((__force u64)vni[2] << 56));
  79 #endif
  80 }
  81
  82 static void geneve_rcv(struct geneve_sock *gs, struct sk_buff *skb)
  83 {
  84         struct vport *vport = gs->rcv_data;
  85         struct genevehdr *geneveh = geneve_hdr(skb);
  86         int opts_len;
  87         struct ovs_tunnel_info tun_info;
  88         __be64 key;
  89         __be16 flags;
  90
  91         opts_len = geneveh->opt_len * 4;
  92
  93         flags = TUNNEL_KEY | TUNNEL_OPTIONS_PRESENT |
  94                 (udp_hdr(skb)->check != 0 ? TUNNEL_CSUM : 0) |
  95                 (geneveh->oam ? TUNNEL_OAM : 0) |
  96                 (geneveh->critical ? TUNNEL_CRIT_OPT : 0);
  97
  98         key = vni_to_tunnel_id(geneveh->vni);
  99
 100         ovs_flow_tun_info_init(&tun_info, ip_hdr(skb),
 101                                udp_hdr(skb)->source, udp_hdr(skb)->dest,
 102                                key, flags,
 103                                geneveh->options, opts_len);
 104
 105         ovs_vport_receive(vport, skb, &tun_info);
 106 }
 107
 108 static int geneve_get_options(const struct vport *vport,
 109                               struct sk_buff *skb)
 110 {
 111         struct geneve_port *geneve_port = geneve_vport(vport);
 112         struct inet_sock *sk = inet_sk(geneve_port->gs->sock->sk);
 113
 114         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(sk->inet_sport)))
 115                 return -EMSGSIZE;
 116         return 0;
 117 }
 118
 119 static void geneve_tnl_destroy(struct vport *vport)
 120 {
 121         struct geneve_port *geneve_port = geneve_vport(vport);
 122
 123         geneve_sock_release(geneve_port->gs);
 124
 125         ovs_vport_deferred_free(vport);
 126 }
 127
 128 static struct vport *geneve_tnl_create(const struct vport_parms *parms)
 129 {
 130         struct net *net = ovs_dp_get_net(parms->dp);
 131         struct nlattr *options = parms->options;
 132         struct geneve_port *geneve_port;
 133         struct geneve_sock *gs;
 134         struct vport *vport;
 135         struct nlattr *a;
 136         int err;
 137         u16 dst_port;
 138
 139         if (!options) {
 140                 err = -EINVAL;
 141                 goto error;
 142         }
 143
 144         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 145         if (a && nla_len(a) == sizeof(u16)) {
 146                 dst_port = nla_get_u16(a);
 147         } else {
 148                 /* Require destination port from userspace. */
 149                 err = -EINVAL;
 150                 goto error;
 151         }
 152
 153         vport = ovs_vport_alloc(sizeof(struct geneve_port),
 154                                 &ovs_geneve_vport_ops, parms);
 155         if (IS_ERR(vport))
 156                 return vport;
 157
 158         geneve_port = geneve_vport(vport);
 159         strncpy(geneve_port->name, parms->name, IFNAMSIZ);
 160
 161         gs = geneve_sock_add(net, htons(dst_port), geneve_rcv, vport, true, 0);
 162         if (IS_ERR(gs)) {
 163                 ovs_vport_free(vport);
 164                 return (void *)gs;
 165         }
 166         geneve_port->gs = gs;
 167
 168         return vport;
 169 error:
 170         return ERR_PTR(err);
 171 }
 172
 173 static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 174 {
 175         struct ovs_key_ipv4_tunnel *tun_key;
 176         struct ovs_tunnel_info *tun_info;
 177         struct net *net = ovs_dp_get_net(vport->dp);
 178         struct geneve_port *geneve_port = geneve_vport(vport);
 179         __be16 dport = inet_sk(geneve_port->gs->sock->sk)->inet_sport;
 180         __be16 sport;
 181         struct rtable *rt;
 182         struct flowi4 fl;
 183         u8 vni[3];
 184         __be16 df;
 185         int err;
 186
 187         tun_info = OVS_CB(skb)->egress_tun_info;
 188         if (unlikely(!tun_info)) {
 189                 err = -EINVAL;
 190                 goto error;
 191         }
 192
 193         tun_key = &tun_info->tunnel;
 194
 195         /* Route lookup */
 196         memset(&fl, 0, sizeof(fl));
 197         fl.daddr = tun_key->ipv4_dst;
 198         fl.saddr = tun_key->ipv4_src;
 199         fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
 200         fl.flowi4_mark = skb->mark;
 201         fl.flowi4_proto = IPPROTO_UDP;
 202
 203         rt = ip_route_output_key(net, &fl);
 204         if (IS_ERR(rt)) {
 205                 err = PTR_ERR(rt);
 206                 goto error;
 207         }
 208
 209         df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 210         sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 211         tunnel_id_to_vni(tun_key->tun_id, vni);
 212         skb->ignore_df = 1;
 213
 214         err = geneve_xmit_skb(geneve_port->gs, rt, skb, fl.saddr,
 215                               tun_key->ipv4_dst, tun_key->ipv4_tos,
 216                               tun_key->ipv4_ttl, df, sport, dport,
 217                               tun_key->tun_flags, vni,
 218                               tun_info->options_len, (u8 *)tun_info->options,
 219                               false);
 220         if (err < 0)
 221                 ip_rt_put(rt);
 222         return err;
 223
 224 error:
 225         kfree_skb(skb);
 226         return err;
 227 }
 228
 229 static const char *geneve_get_name(const struct vport *vport)
 230 {
 231         struct geneve_port *geneve_port = geneve_vport(vport);
 232
 233         return geneve_port->name;
 234 }
 235
 236 static int geneve_get_egress_tun_info(struct vport *vport, struct sk_buff *skb,
 237                                       struct ovs_tunnel_info *egress_tun_info)
 238 {
 239         struct geneve_port *geneve_port = geneve_vport(vport);
 240         struct net *net = ovs_dp_get_net(vport->dp);
 241         __be16 dport = inet_sk(geneve_port->gs->sock->sk)->inet_sport;
 242         __be16 sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 243
 244         /* Get tp_src and tp_dst, refert to geneve_build_header().
 245          */
 246         return ovs_tunnel_get_egress_info(egress_tun_info,
 247                                           ovs_dp_get_net(vport->dp),
 248                                           OVS_CB(skb)->egress_tun_info,
 249                                           IPPROTO_UDP, skb->mark, sport, dport);
 250 }
 251
 252 static struct vport_ops ovs_geneve_vport_ops = {
 253         .type           = OVS_VPORT_TYPE_GENEVE,
 254         .create         = geneve_tnl_create,
 255         .destroy        = geneve_tnl_destroy,
 256         .get_name       = geneve_get_name,
 257         .get_options    = geneve_get_options,
 258         .send           = geneve_tnl_send,
 259         .owner          = THIS_MODULE,
 260         .get_egress_tun_info    = geneve_get_egress_tun_info,
 261 };
 262
 263 static int __init ovs_geneve_tnl_init(void)
 264 {
 265         return ovs_vport_ops_register(&ovs_geneve_vport_ops);
 266 }
 267
 268 static void __exit ovs_geneve_tnl_exit(void)
 269 {
 270         ovs_vport_ops_unregister(&ovs_geneve_vport_ops);
 271 }
 272
 273 module_init(ovs_geneve_tnl_init);
 274 module_exit(ovs_geneve_tnl_exit);
 275
 276 MODULE_DESCRIPTION("OVS: Geneve swiching port");
 277 MODULE_LICENSE("GPL");
 278 MODULE_ALIAS("vport-type-5");