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 static inline struct genevehdr *geneve_hdr(const struct sk_buff *skb)
  50 {
  51         return (struct genevehdr *)(udp_hdr(skb) + 1);
  52 }
  53
  54 /* Convert 64 bit tunnel ID to 24 bit VNI. */
  55 static void tunnel_id_to_vni(__be64 tun_id, __u8 *vni)
  56 {
  57 #ifdef __BIG_ENDIAN
  58         vni[0] = (__force __u8)(tun_id >> 16);
  59         vni[1] = (__force __u8)(tun_id >> 8);
  60         vni[2] = (__force __u8)tun_id;
  61 #else
  62         vni[0] = (__force __u8)((__force u64)tun_id >> 40);
  63         vni[1] = (__force __u8)((__force u64)tun_id >> 48);
  64         vni[2] = (__force __u8)((__force u64)tun_id >> 56);
  65 #endif
  66 }
  67
  68 /* Convert 24 bit VNI to 64 bit tunnel ID. */
  69 static __be64 vni_to_tunnel_id(const __u8 *vni)
  70 {
  71 #ifdef __BIG_ENDIAN
  72         return (vni[0] << 16) | (vni[1] << 8) | vni[2];
  73 #else
  74         return (__force __be64)(((__force u64)vni[0] << 40) |
  75                                 ((__force u64)vni[1] << 48) |
  76                                 ((__force u64)vni[2] << 56));
  77 #endif
  78 }
  79
  80 static void geneve_rcv(struct geneve_sock *gs, struct sk_buff *skb)
  81 {
  82         struct vport *vport = gs->rcv_data;
  83         struct genevehdr *geneveh = geneve_hdr(skb);
  84         int opts_len;
  85         struct ovs_tunnel_info tun_info;
  86         __be64 key;
  87         __be16 flags;
  88
  89         opts_len = geneveh->opt_len * 4;
  90
  91         flags = TUNNEL_KEY | TUNNEL_GENEVE_OPT |
  92                 (udp_hdr(skb)->check != 0 ? TUNNEL_CSUM : 0) |
  93                 (geneveh->oam ? TUNNEL_OAM : 0) |
  94                 (geneveh->critical ? TUNNEL_CRIT_OPT : 0);
  95
  96         key = vni_to_tunnel_id(geneveh->vni);
  97
  98         ovs_flow_tun_info_init(&tun_info, ip_hdr(skb),
  99                                udp_hdr(skb)->source, udp_hdr(skb)->dest,
 100                                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         __be16 dst_port = inet_sport(geneve_port->gs->sock->sk);
 111
 112         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
 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         const 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_sport(geneve_port->gs->sock->sk);
 178         __be16 sport;
 179         __be32 saddr;
 180         struct rtable *rt;
 181         u8 vni[3], opts_len, *opts;
 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         saddr = tun_key->ipv4_src;
 194         rt = find_route(ovs_dp_get_net(vport->dp),
 195                         &saddr, tun_key->ipv4_dst,
 196                         IPPROTO_UDP, tun_key->ipv4_tos,
 197                         skb->mark);
 198         if (IS_ERR(rt)) {
 199                 err = PTR_ERR(rt);
 200                 goto error;
 201         }
 202
 203         df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 204         sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 205         tunnel_id_to_vni(tun_key->tun_id, vni);
 206         skb->ignore_df = 1;
 207
 208         if (tun_key->tun_flags & TUNNEL_GENEVE_OPT) {
 209                 opts = (u8 *)tun_info->options;
 210                 opts_len = tun_info->options_len;
 211         } else {
 212                 opts = NULL;
 213                 opts_len = 0;
 214         }
 215
 216         err = geneve_xmit_skb(geneve_port->gs, rt, skb, saddr,
 217                               tun_key->ipv4_dst, tun_key->ipv4_tos,
 218                               tun_key->ipv4_ttl, df, sport, dport,
 219                               tun_key->tun_flags, vni, opts_len, opts,
 220                               !!(tun_key->tun_flags & TUNNEL_CSUM), false);
 221         if (err < 0)
 222                 ip_rt_put(rt);
 223         return err;
 224
 225 error:
 226         kfree_skb(skb);
 227         return err;
 228 }
 229
 230 static const char *geneve_get_name(const struct vport *vport)
 231 {
 232         struct geneve_port *geneve_port = geneve_vport(vport);
 233
 234         return geneve_port->name;
 235 }
 236
 237 static int geneve_get_egress_tun_info(struct vport *vport, struct sk_buff *skb,
 238                                       struct ovs_tunnel_info *egress_tun_info)
 239 {
 240         struct geneve_port *geneve_port = geneve_vport(vport);
 241         struct net *net = ovs_dp_get_net(vport->dp);
 242         __be16 dport = inet_sport(geneve_port->gs->sock->sk);
 243         __be16 sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 244
 245         /* Get tp_src and tp_dst, refert to geneve_build_header().
 246          */
 247         return ovs_tunnel_get_egress_info(egress_tun_info,
 248                                           ovs_dp_get_net(vport->dp),
 249                                           OVS_CB(skb)->egress_tun_info,
 250                                           IPPROTO_UDP, skb->mark, sport, dport);
 251 }
 252
 253 static struct vport_ops ovs_geneve_vport_ops = {
 254         .type                   = OVS_VPORT_TYPE_GENEVE,
 255         .create                 = geneve_tnl_create,
 256         .destroy                = geneve_tnl_destroy,
 257         .get_name               = geneve_get_name,
 258         .get_options            = geneve_get_options,
 259         .send                   = geneve_tnl_send,
 260         .get_egress_tun_info    = geneve_get_egress_tun_info,
 261         .owner                  = THIS_MODULE,
 262 };
 263
 264 static int __init ovs_geneve_tnl_init(void)
 265 {
 266         return ovs_vport_ops_register(&ovs_geneve_vport_ops);
 267 }
 268
 269 static void __exit ovs_geneve_tnl_exit(void)
 270 {
 271         ovs_vport_ops_unregister(&ovs_geneve_vport_ops);
 272 }
 273
 274 module_init(ovs_geneve_tnl_init);
 275 module_exit(ovs_geneve_tnl_exit);
 276
 277 MODULE_DESCRIPTION("OVS: Geneve swiching port");
 278 MODULE_LICENSE("GPL");
 279 MODULE_ALIAS("vport-type-5");