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
  21 #include <net/geneve.h>
  22 #include <net/icmp.h>
  23 #include <net/ip.h>
  24 #include <net/route.h>
  25 #include <net/udp.h>
  26 #include <net/xfrm.h>
  27
  28 #include "datapath.h"
  29 #include "vport.h"
  30
  31 /**
  32  * struct geneve_port - Keeps track of open UDP ports
  33  * @sock: The socket created for this port number.
  34  * @name: vport name.
  35  */
  36 struct geneve_port {
  37         struct geneve_sock *gs;
  38         char name[IFNAMSIZ];
  39 };
  40
  41 static LIST_HEAD(geneve_ports);
  42
  43 static inline struct geneve_port *geneve_vport(const struct vport *vport)
  44 {
  45         return vport_priv(vport);
  46 }
  47
  48 static inline struct genevehdr *geneve_hdr(const struct sk_buff *skb)
  49 {
  50         return (struct genevehdr *)(udp_hdr(skb) + 1);
  51 }
  52
  53 /* Convert 64 bit tunnel ID to 24 bit VNI. */
  54 static void tunnel_id_to_vni(__be64 tun_id, __u8 *vni)
  55 {
  56 #ifdef __BIG_ENDIAN
  57         vni[0] = (__force __u8)(tun_id >> 16);
  58         vni[1] = (__force __u8)(tun_id >> 8);
  59         vni[2] = (__force __u8)tun_id;
  60 #else
  61         vni[0] = (__force __u8)((__force u64)tun_id >> 40);
  62         vni[1] = (__force __u8)((__force u64)tun_id >> 48);
  63         vni[2] = (__force __u8)((__force u64)tun_id >> 56);
  64 #endif
  65 }
  66
  67 /* Convert 24 bit VNI to 64 bit tunnel ID. */
  68 static __be64 vni_to_tunnel_id(__u8 *vni)
  69 {
  70 #ifdef __BIG_ENDIAN
  71         return (vni[0] << 16) | (vni[1] << 8) | vni[2];
  72 #else
  73         return (__force __be64)(((__force u64)vni[0] << 40) |
  74                                 ((__force u64)vni[1] << 48) |
  75                                 ((__force u64)vni[2] << 56));
  76 #endif
  77 }
  78
  79 static void geneve_rcv(struct geneve_sock *gs, struct sk_buff *skb)
  80 {
  81         struct vport *vport = gs->rcv_data;
  82         struct genevehdr *geneveh = geneve_hdr(skb);
  83         int opts_len;
  84         struct ovs_tunnel_info tun_info;
  85         __be64 key;
  86         __be16 flags;
  87
  88         opts_len = geneveh->opt_len * 4;
  89
  90         flags = TUNNEL_KEY | TUNNEL_OPTIONS_PRESENT |
  91                 (udp_hdr(skb)->check != 0 ? TUNNEL_CSUM : 0) |
  92                 (geneveh->oam ? TUNNEL_OAM : 0) |
  93                 (geneveh->critical ? TUNNEL_CRIT_OPT : 0);
  94
  95         key = vni_to_tunnel_id(geneveh->vni);
  96
  97         ovs_flow_tun_info_init(&tun_info, ip_hdr(skb), key, flags,
  98                                geneveh->options, opts_len);
  99
 100         ovs_vport_receive(vport, skb, &tun_info);
 101 }
 102
 103 static int geneve_get_options(const struct vport *vport,
 104                               struct sk_buff *skb)
 105 {
 106         struct geneve_port *geneve_port = geneve_vport(vport);
 107         __be16 sport;
 108
 109         sport = ntohs(inet_sk(geneve_port->gs->sock->sk)->inet_sport);
 110         if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, sport))
 111                 return -EMSGSIZE;
 112         return 0;
 113 }
 114
 115 static void geneve_tnl_destroy(struct vport *vport)
 116 {
 117         struct geneve_port *geneve_port = geneve_vport(vport);
 118
 119         geneve_sock_release(geneve_port->gs);
 120
 121         ovs_vport_deferred_free(vport);
 122 }
 123
 124 static struct vport *geneve_tnl_create(const struct vport_parms *parms)
 125 {
 126         struct net *net = ovs_dp_get_net(parms->dp);
 127         struct nlattr *options = parms->options;
 128         struct geneve_port *geneve_port;
 129         struct geneve_sock *gs;
 130         struct vport *vport;
 131         struct nlattr *a;
 132         int err;
 133         u16 dst_port;
 134
 135         if (!options) {
 136                 err = -EINVAL;
 137                 goto error;
 138         }
 139
 140         a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
 141         if (a && nla_len(a) == sizeof(u16)) {
 142                 dst_port = nla_get_u16(a);
 143         } else {
 144                 /* Require destination port from userspace. */
 145                 err = -EINVAL;
 146                 goto error;
 147         }
 148
 149         vport = ovs_vport_alloc(sizeof(struct geneve_port),
 150                                 &ovs_geneve_vport_ops, parms);
 151         if (IS_ERR(vport))
 152                 return vport;
 153
 154         geneve_port = geneve_vport(vport);
 155         strncpy(geneve_port->name, parms->name, IFNAMSIZ);
 156
 157         gs = geneve_sock_add(net, htons(dst_port), geneve_rcv, vport, true, 0);
 158         if (IS_ERR(gs)) {
 159                 ovs_vport_free(vport);
 160                 return (void *)gs;
 161         }
 162         geneve_port->gs = gs;
 163
 164         return vport;
 165 error:
 166         return ERR_PTR(err);
 167 }
 168
 169 static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 170 {
 171         struct ovs_key_ipv4_tunnel *tun_key;
 172         struct ovs_tunnel_info *tun_info;
 173         struct net *net = ovs_dp_get_net(vport->dp);
 174         struct geneve_port *geneve_port = geneve_vport(vport);
 175         __be16 dport = inet_sk(geneve_port->gs->sock->sk)->inet_sport;
 176         __be16 sport;
 177         struct rtable *rt;
 178         struct flowi4 fl;
 179         u8 vni[3];
 180         __be16 df;
 181         int err;
 182
 183         tun_info = OVS_CB(skb)->egress_tun_info;
 184         if (unlikely(!tun_info)) {
 185                 err = -EINVAL;
 186                 goto error;
 187         }
 188
 189         tun_key = &tun_info->tunnel;
 190
 191         /* Route lookup */
 192         memset(&fl, 0, sizeof(fl));
 193         fl.daddr = tun_key->ipv4_dst;
 194         fl.saddr = tun_key->ipv4_src;
 195         fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
 196         fl.flowi4_mark = skb->mark;
 197         fl.flowi4_proto = IPPROTO_UDP;
 198
 199         rt = ip_route_output_key(net, &fl);
 200         if (IS_ERR(rt)) {
 201                 err = PTR_ERR(rt);
 202                 goto error;
 203         }
 204
 205         df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 206         sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
 207         tunnel_id_to_vni(tun_key->tun_id, vni);
 208         skb->ignore_df = 1;
 209
 210         err = geneve_xmit_skb(geneve_port->gs, rt, skb, fl.saddr,
 211                               tun_key->ipv4_dst, tun_key->ipv4_tos,
 212                               tun_key->ipv4_ttl, df, sport, dport,
 213                               tun_key->tun_flags, vni,
 214                               tun_info->options_len, (u8 *)tun_info->options,
 215                               false);
 216         if (err < 0)
 217                 ip_rt_put(rt);
 218 error:
 219         return err;
 220 }
 221
 222 static const char *geneve_get_name(const struct vport *vport)
 223 {
 224         struct geneve_port *geneve_port = geneve_vport(vport);
 225
 226         return geneve_port->name;
 227 }
 228
 229 const struct vport_ops ovs_geneve_vport_ops = {
 230         .type           = OVS_VPORT_TYPE_GENEVE,
 231         .create         = geneve_tnl_create,
 232         .destroy        = geneve_tnl_destroy,
 233         .get_name       = geneve_get_name,
 234         .get_options    = geneve_get_options,
 235         .send           = geneve_tnl_send,
 236 };