datapath/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 ovs_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         ovs_flow_tun_info_init(&tun_info, ip_hdr(skb),
  94                                udp_hdr(skb)->source, udp_hdr(skb)->dest,
  95                                key, flags,
  96                                geneveh->options, opts_len);
  97
  98         ovs_vport_receive(vport, skb, &tun_info);
  99 }
 100
 101 static int geneve_get_options(const struct vport *vport,
 102                               struct sk_buff *skb)
 103 {
 104         struct geneve_port *geneve_port = geneve_vport(vport);
 105         __be16 dst_port = inet_sport(geneve_port->gs->sock->sk);
 106
 107         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
 108                 return -EMSGSIZE;
 109         return 0;
 110 }
 111
 112 static void geneve_tnl_destroy(struct vport *vport)
 113 {
 114         struct geneve_port *geneve_port = geneve_vport(vport);
 115
 116         geneve_sock_release(geneve_port->gs);
 117
 118         ovs_vport_deferred_free(vport);
 119 }
 120
 121 static struct vport *geneve_tnl_create(const struct vport_parms *parms)
 122 {
 123         struct net *net = ovs_dp_get_net(parms->dp);
 124         struct nlattr *options = parms->options;
 125         struct geneve_port *geneve_port;
 126         struct geneve_sock *gs;
 127         struct vport *vport;
 128         struct nlattr *a;
 129         int err;
 130         u16 dst_port;
 131
 132         if (!options) {
 133                 err = -EINVAL;
 134                 goto error;
 135         }
 136
 137         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 138         if (a && nla_len(a) == sizeof(u16)) {
 139                 dst_port = nla_get_u16(a);
 140         } else {
 141                 /* Require destination port from userspace. */
 142                 err = -EINVAL;
 143                 goto error;
 144         }
 145
 146         vport = ovs_vport_alloc(sizeof(struct geneve_port),
 147                                 &ovs_geneve_vport_ops, parms);
 148         if (IS_ERR(vport))
 149                 return vport;
 150
 151         geneve_port = geneve_vport(vport);
 152         strncpy(geneve_port->name, parms->name, IFNAMSIZ);
 153
 154         gs = geneve_sock_add(net, htons(dst_port), geneve_rcv, vport, true, 0);
 155         if (IS_ERR(gs)) {
 156                 ovs_vport_free(vport);
 157                 return (void *)gs;
 158         }
 159         geneve_port->gs = gs;
 160
 161         return vport;
 162 error:
 163         return ERR_PTR(err);
 164 }
 165
 166 static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 167 {
 168         const struct ovs_key_ipv4_tunnel *tun_key;
 169         struct ovs_tunnel_info *tun_info;
 170         struct net *net = ovs_dp_get_net(vport->dp);
 171         struct geneve_port *geneve_port = geneve_vport(vport);
 172         __be16 dport = inet_sport(geneve_port->gs->sock->sk);
 173         __be16 sport;
 174         __be32 saddr;
 175         struct rtable *rt;
 176         u8 vni[3], opts_len, *opts;
 177         __be16 df;
 178         int err;
 179
 180         tun_info = OVS_CB(skb)->egress_tun_info;
 181         if (unlikely(!tun_info)) {
 182                 err = -EINVAL;
 183                 goto error;
 184         }
 185
 186         tun_key = &tun_info->tunnel;
 187
 188         saddr = tun_key->ipv4_src;
 189         rt = find_route(ovs_dp_get_net(vport->dp),
 190                         &saddr, tun_key->ipv4_dst,
 191                         IPPROTO_UDP, tun_key->ipv4_tos,
 192                         skb->mark);
 193         if (IS_ERR(rt)) {
 194                 err = PTR_ERR(rt);
 195                 goto error;
 196         }
 197
 198         df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 199         sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 200         tunnel_id_to_vni(tun_key->tun_id, vni);
 201         skb->ignore_df = 1;
 202
 203         if (tun_key->tun_flags & TUNNEL_GENEVE_OPT) {
 204                 opts = (u8 *)tun_info->options;
 205                 opts_len = tun_info->options_len;
 206         } else {
 207                 opts = NULL;
 208                 opts_len = 0;
 209         }
 210
 211         err = geneve_xmit_skb(geneve_port->gs, rt, skb, saddr,
 212                               tun_key->ipv4_dst, tun_key->ipv4_tos,
 213                               tun_key->ipv4_ttl, df, sport, dport,
 214                               tun_key->tun_flags, vni, opts_len, opts,
 215                               !!(tun_key->tun_flags & TUNNEL_CSUM), false);
 216         if (err < 0)
 217                 ip_rt_put(rt);
 218         return err;
 219
 220 error:
 221         kfree_skb(skb);
 222         return err;
 223 }
 224
 225 static const char *geneve_get_name(const struct vport *vport)
 226 {
 227         struct geneve_port *geneve_port = geneve_vport(vport);
 228
 229         return geneve_port->name;
 230 }
 231
 232 static int geneve_get_egress_tun_info(struct vport *vport, struct sk_buff *skb,
 233                                       struct ovs_tunnel_info *egress_tun_info)
 234 {
 235         struct geneve_port *geneve_port = geneve_vport(vport);
 236         struct net *net = ovs_dp_get_net(vport->dp);
 237         __be16 dport = inet_sport(geneve_port->gs->sock->sk);
 238         __be16 sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 239
 240         /* Get tp_src and tp_dst, refert to geneve_build_header().
 241          */
 242         return ovs_tunnel_get_egress_info(egress_tun_info,
 243                                           ovs_dp_get_net(vport->dp),
 244                                           OVS_CB(skb)->egress_tun_info,
 245                                           IPPROTO_UDP, skb->mark, sport, dport);
 246 }
 247
 248 static struct vport_ops ovs_geneve_vport_ops = {
 249         .type                   = OVS_VPORT_TYPE_GENEVE,
 250         .create                 = geneve_tnl_create,
 251         .destroy                = geneve_tnl_destroy,
 252         .get_name               = geneve_get_name,
 253         .get_options            = geneve_get_options,
 254         .send                   = geneve_tnl_send,
 255         .get_egress_tun_info    = geneve_get_egress_tun_info,
 256         .owner                  = THIS_MODULE,
 257 };
 258
 259 static int __init ovs_geneve_tnl_init(void)
 260 {
 261         return ovs_vport_ops_register(&ovs_geneve_vport_ops);
 262 }
 263
 264 static void __exit ovs_geneve_tnl_exit(void)
 265 {
 266         ovs_vport_ops_unregister(&ovs_geneve_vport_ops);
 267 }
 268
 269 module_init(ovs_geneve_tnl_init);
 270 module_exit(ovs_geneve_tnl_exit);
 271
 272 MODULE_DESCRIPTION("OVS: Geneve swiching port");
 273 MODULE_LICENSE("GPL");
 274 MODULE_ALIAS("vport-type-5");