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(__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), key, flags,
 101                                geneveh->options, opts_len);
 102
 103         ovs_vport_receive(vport, skb, &tun_info);
 104 }
 105
 106 static int geneve_get_options(const struct vport *vport,
 107                               struct sk_buff *skb)
 108 {
 109         struct geneve_port *geneve_port = geneve_vport(vport);
 110         struct inet_sock *sk = inet_sk(geneve_port->gs->sock->sk);
 111
 112         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(sk->inet_sport)))
 113                 return -EMSGSIZE;
 114         return 0;
 115 }
 116
 117 static void geneve_tnl_destroy(struct vport *vport)
 118 {
 119         struct geneve_port *geneve_port = geneve_vport(vport);
 120
 121         geneve_sock_release(geneve_port->gs);
 122
 123         ovs_vport_deferred_free(vport);
 124 }
 125
 126 static struct vport *geneve_tnl_create(const struct vport_parms *parms)
 127 {
 128         struct net *net = ovs_dp_get_net(parms->dp);
 129         struct nlattr *options = parms->options;
 130         struct geneve_port *geneve_port;
 131         struct geneve_sock *gs;
 132         struct vport *vport;
 133         struct nlattr *a;
 134         int err;
 135         u16 dst_port;
 136
 137         if (!options) {
 138                 err = -EINVAL;
 139                 goto error;
 140         }
 141
 142         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 143         if (a && nla_len(a) == sizeof(u16)) {
 144                 dst_port = nla_get_u16(a);
 145         } else {
 146                 /* Require destination port from userspace. */
 147                 err = -EINVAL;
 148                 goto error;
 149         }
 150
 151         vport = ovs_vport_alloc(sizeof(struct geneve_port),
 152                                 &ovs_geneve_vport_ops, parms);
 153         if (IS_ERR(vport))
 154                 return vport;
 155
 156         geneve_port = geneve_vport(vport);
 157         strncpy(geneve_port->name, parms->name, IFNAMSIZ);
 158
 159         gs = geneve_sock_add(net, htons(dst_port), geneve_rcv, vport, true, 0);
 160         if (IS_ERR(gs)) {
 161                 ovs_vport_free(vport);
 162                 return (void *)gs;
 163         }
 164         geneve_port->gs = gs;
 165
 166         return vport;
 167 error:
 168         return ERR_PTR(err);
 169 }
 170
 171 static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 172 {
 173         struct ovs_key_ipv4_tunnel *tun_key;
 174         struct ovs_tunnel_info *tun_info;
 175         struct net *net = ovs_dp_get_net(vport->dp);
 176         struct geneve_port *geneve_port = geneve_vport(vport);
 177         __be16 dport = inet_sk(geneve_port->gs->sock->sk)->inet_sport;
 178         __be16 sport;
 179         struct rtable *rt;
 180         struct flowi4 fl;
 181         u8 vni[3];
 182         __be16 df;
 183         int err;
 184
 185         tun_info = OVS_CB(skb)->egress_tun_info;
 186         if (unlikely(!tun_info)) {
 187                 err = -EINVAL;
 188                 goto error;
 189         }
 190
 191         tun_key = &tun_info->tunnel;
 192
 193         /* Route lookup */
 194         memset(&fl, 0, sizeof(fl));
 195         fl.daddr = tun_key->ipv4_dst;
 196         fl.saddr = tun_key->ipv4_src;
 197         fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
 198         fl.flowi4_mark = skb->mark;
 199         fl.flowi4_proto = IPPROTO_UDP;
 200
 201         rt = ip_route_output_key(net, &fl);
 202         if (IS_ERR(rt)) {
 203                 err = PTR_ERR(rt);
 204                 goto error;
 205         }
 206
 207         df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 208         sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 209         tunnel_id_to_vni(tun_key->tun_id, vni);
 210         skb->ignore_df = 1;
 211
 212         err = geneve_xmit_skb(geneve_port->gs, rt, skb, fl.saddr,
 213                               tun_key->ipv4_dst, tun_key->ipv4_tos,
 214                               tun_key->ipv4_ttl, df, sport, dport,
 215                               tun_key->tun_flags, vni,
 216                               tun_info->options_len, (u8 *)tun_info->options,
 217                               false);
 218         if (err < 0)
 219                 ip_rt_put(rt);
 220 error:
 221         return err;
 222 }
 223
 224 static const char *geneve_get_name(const struct vport *vport)
 225 {
 226         struct geneve_port *geneve_port = geneve_vport(vport);
 227
 228         return geneve_port->name;
 229 }
 230
 231 static struct vport_ops ovs_geneve_vport_ops = {
 232         .type           = OVS_VPORT_TYPE_GENEVE,
 233         .create         = geneve_tnl_create,
 234         .destroy        = geneve_tnl_destroy,
 235         .get_name       = geneve_get_name,
 236         .get_options    = geneve_get_options,
 237         .send           = geneve_tnl_send,
 238         .owner          = THIS_MODULE,
 239 };
 240
 241 static int __init ovs_geneve_tnl_init(void)
 242 {
 243         return ovs_vport_ops_register(&ovs_geneve_vport_ops);
 244 }
 245
 246 static void __exit ovs_geneve_tnl_exit(void)
 247 {
 248         ovs_vport_ops_unregister(&ovs_geneve_vport_ops);
 249 }
 250
 251 module_init(ovs_geneve_tnl_init);
 252 module_exit(ovs_geneve_tnl_exit);
 253
 254 MODULE_DESCRIPTION("OVS: Geneve swiching port");
 255 MODULE_LICENSE("GPL");
 256 MODULE_ALIAS("vport-type-5");