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/in.h>
  13 #include <linux/ip.h>
  14 #include <linux/net.h>
  15 #include <linux/rculist.h>
  16 #include <linux/udp.h>
  17 #include <linux/if_vlan.h>
  18 #include <linux/module.h>
  19
  20 #include <net/geneve.h>
  21 #include <net/icmp.h>
  22 #include <net/ip.h>
  23 #include <net/route.h>
  24 #include <net/udp.h>
  25 #include <net/xfrm.h>
  26
  27 #include "datapath.h"
  28 #include "vport.h"
  29
  30 static struct vport_ops ovs_geneve_vport_ops;
  31
  32 /**
  33  * struct geneve_port - Keeps track of open UDP ports
  34  * @gs: The socket created for this port number.
  35  * @name: vport name.
  36  */
  37 struct geneve_port {
  38         struct geneve_sock *gs;
  39         char name[IFNAMSIZ];
  40 };
  41
  42 static LIST_HEAD(geneve_ports);
  43
  44 static inline struct geneve_port *geneve_vport(const struct vport *vport)
  45 {
  46         return vport_priv(vport);
  47 }
  48
  49 /* Convert 64 bit tunnel ID to 24 bit VNI. */
  50 static void tunnel_id_to_vni(__be64 tun_id, __u8 *vni)
  51 {
  52 #ifdef __BIG_ENDIAN
  53         vni[0] = (__force __u8)(tun_id >> 16);
  54         vni[1] = (__force __u8)(tun_id >> 8);
  55         vni[2] = (__force __u8)tun_id;
  56 #else
  57         vni[0] = (__force __u8)((__force u64)tun_id >> 40);
  58         vni[1] = (__force __u8)((__force u64)tun_id >> 48);
  59         vni[2] = (__force __u8)((__force u64)tun_id >> 56);
  60 #endif
  61 }
  62
  63 /* Convert 24 bit VNI to 64 bit tunnel ID. */
  64 static __be64 vni_to_tunnel_id(const __u8 *vni)
  65 {
  66 #ifdef __BIG_ENDIAN
  67         return (vni[0] << 16) | (vni[1] << 8) | vni[2];
  68 #else
  69         return (__force __be64)(((__force u64)vni[0] << 40) |
  70                                 ((__force u64)vni[1] << 48) |
  71                                 ((__force u64)vni[2] << 56));
  72 #endif
  73 }
  74
  75 static void geneve_rcv(struct geneve_sock *gs, struct sk_buff *skb)
  76 {
  77         struct vport *vport = gs->rcv_data;
  78         struct genevehdr *geneveh = geneve_hdr(skb);
  79         int opts_len;
  80         struct ip_tunnel_info tun_info;
  81         __be64 key;
  82         __be16 flags;
  83
  84         opts_len = geneveh->opt_len * 4;
  85
  86         flags = TUNNEL_KEY | TUNNEL_GENEVE_OPT |
  87                 (udp_hdr(skb)->check != 0 ? TUNNEL_CSUM : 0) |
  88                 (geneveh->oam ? TUNNEL_OAM : 0) |
  89                 (geneveh->critical ? TUNNEL_CRIT_OPT : 0);
  90
  91         key = vni_to_tunnel_id(geneveh->vni);
  92
  93         ip_tunnel_info_init(&tun_info, ip_hdr(skb),
  94                             udp_hdr(skb)->source, udp_hdr(skb)->dest,
  95                             key, flags, geneveh->options, opts_len);
  96
  97         ovs_vport_receive(vport, skb, &tun_info);
  98 }
  99
 100 static int geneve_get_options(const struct vport *vport,
 101                               struct sk_buff *skb)
 102 {
 103         struct geneve_port *geneve_port = geneve_vport(vport);
 104         struct inet_sock *sk = inet_sk(geneve_port->gs->sock->sk);
 105
 106         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(sk->inet_sport)))
 107                 return -EMSGSIZE;
 108         return 0;
 109 }
 110
 111 static void geneve_tnl_destroy(struct vport *vport)
 112 {
 113         struct geneve_port *geneve_port = geneve_vport(vport);
 114
 115         geneve_sock_release(geneve_port->gs);
 116
 117         ovs_vport_deferred_free(vport);
 118 }
 119
 120 static struct vport *geneve_tnl_create(const struct vport_parms *parms)
 121 {
 122         struct net *net = ovs_dp_get_net(parms->dp);
 123         struct nlattr *options = parms->options;
 124         struct geneve_port *geneve_port;
 125         struct geneve_sock *gs;
 126         struct vport *vport;
 127         struct nlattr *a;
 128         int err;
 129         u16 dst_port;
 130
 131         if (!options) {
 132                 err = -EINVAL;
 133                 goto error;
 134         }
 135
 136         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 137         if (a && nla_len(a) == sizeof(u16)) {
 138                 dst_port = nla_get_u16(a);
 139         } else {
 140                 /* Require destination port from userspace. */
 141                 err = -EINVAL;
 142                 goto error;
 143         }
 144
 145         vport = ovs_vport_alloc(sizeof(struct geneve_port),
 146                                 &ovs_geneve_vport_ops, parms);
 147         if (IS_ERR(vport))
 148                 return vport;
 149
 150         geneve_port = geneve_vport(vport);
 151         strncpy(geneve_port->name, parms->name, IFNAMSIZ);
 152
 153         gs = geneve_sock_add(net, htons(dst_port), geneve_rcv, vport, true, 0);
 154         if (IS_ERR(gs)) {
 155                 ovs_vport_free(vport);
 156                 return (void *)gs;
 157         }
 158         geneve_port->gs = gs;
 159
 160         return vport;
 161 error:
 162         return ERR_PTR(err);
 163 }
 164
 165 static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 166 {
 167         const struct ip_tunnel_key *tun_key;
 168         struct ip_tunnel_info *tun_info;
 169         struct net *net = ovs_dp_get_net(vport->dp);
 170         struct geneve_port *geneve_port = geneve_vport(vport);
 171         __be16 dport = inet_sk(geneve_port->gs->sock->sk)->inet_sport;
 172         __be16 sport;
 173         struct rtable *rt;
 174         struct flowi4 fl;
 175         u8 vni[3], opts_len, *opts;
 176         __be16 df;
 177         int err;
 178
 179         tun_info = OVS_CB(skb)->egress_tun_info;
 180         if (unlikely(!tun_info)) {
 181                 err = -EINVAL;
 182                 goto error;
 183         }
 184
 185         tun_key = &tun_info->key;
 186         rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_UDP);
 187         if (IS_ERR(rt)) {
 188                 err = PTR_ERR(rt);
 189                 goto error;
 190         }
 191
 192         df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 193         sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 194         tunnel_id_to_vni(tun_key->tun_id, vni);
 195         skb->ignore_df = 1;
 196
 197         if (tun_key->tun_flags & TUNNEL_GENEVE_OPT) {
 198                 opts = (u8 *)tun_info->options;
 199                 opts_len = tun_info->options_len;
 200         } else {
 201                 opts = NULL;
 202                 opts_len = 0;
 203         }
 204
 205         err = geneve_xmit_skb(geneve_port->gs, rt, skb, fl.saddr,
 206                               tun_key->u.ipv4.dst, tun_key->ipv4_tos,
 207                               tun_key->ipv4_ttl, df, sport, dport,
 208                               tun_key->tun_flags, vni, opts_len, opts,
 209                               !!(tun_key->tun_flags & TUNNEL_CSUM), false);
 210         if (err < 0)
 211                 ip_rt_put(rt);
 212         return err;
 213
 214 error:
 215         kfree_skb(skb);
 216         return err;
 217 }
 218
 219 static const char *geneve_get_name(const struct vport *vport)
 220 {
 221         struct geneve_port *geneve_port = geneve_vport(vport);
 222
 223         return geneve_port->name;
 224 }
 225
 226 static int geneve_get_egress_tun_info(struct vport *vport, struct sk_buff *skb,
 227                                       struct ip_tunnel_info *egress_tun_info)
 228 {
 229         struct geneve_port *geneve_port = geneve_vport(vport);
 230         struct net *net = ovs_dp_get_net(vport->dp);
 231         __be16 dport = inet_sk(geneve_port->gs->sock->sk)->inet_sport;
 232         __be16 sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 233
 234         /* Get tp_src and tp_dst, refert to geneve_build_header().
 235          */
 236         return ovs_tunnel_get_egress_info(egress_tun_info,
 237                                           ovs_dp_get_net(vport->dp),
 238                                           OVS_CB(skb)->egress_tun_info,
 239                                           IPPROTO_UDP, skb->mark, sport, dport);
 240 }
 241
 242 static struct vport_ops ovs_geneve_vport_ops = {
 243         .type           = OVS_VPORT_TYPE_GENEVE,
 244         .create         = geneve_tnl_create,
 245         .destroy        = geneve_tnl_destroy,
 246         .get_name       = geneve_get_name,
 247         .get_options    = geneve_get_options,
 248         .send           = geneve_tnl_send,
 249         .owner          = THIS_MODULE,
 250         .get_egress_tun_info    = geneve_get_egress_tun_info,
 251 };
 252
 253 static int __init ovs_geneve_tnl_init(void)
 254 {
 255         return ovs_vport_ops_register(&ovs_geneve_vport_ops);
 256 }
 257
 258 static void __exit ovs_geneve_tnl_exit(void)
 259 {
 260         ovs_vport_ops_unregister(&ovs_geneve_vport_ops);
 261 }
 262
 263 module_init(ovs_geneve_tnl_init);
 264 module_exit(ovs_geneve_tnl_exit);
 265
 266 MODULE_DESCRIPTION("OVS: Geneve swiching port");
 267 MODULE_LICENSE("GPL");
 268 MODULE_ALIAS("vport-type-5");