2 * Copyright (c) 2007-2014 Nicira, Inc.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 #include <linux/skbuff.h>
24 #include <linux/if_tunnel.h>
25 #include <linux/if_vlan.h>
27 #include <linux/in_route.h>
28 #include <linux/inetdevice.h>
29 #include <linux/jhash.h>
30 #include <linux/list.h>
31 #include <linux/kernel.h>
32 #include <linux/workqueue.h>
33 #include <linux/rculist.h>
34 #include <net/route.h>
39 #include <net/ip_tunnels.h>
41 #include <net/net_namespace.h>
42 #include <net/netns/generic.h>
43 #include <net/protocol.h>
48 /* Returns the least-significant 32 bits of a __be64. */
49 static __be32 be64_get_low32(__be64 x)
52 return (__force __be32)x;
54 return (__force __be32)((__force u64)x >> 32);
58 static __be16 filter_tnl_flags(__be16 flags)
60 return flags & (TUNNEL_CSUM | TUNNEL_KEY);
63 static struct sk_buff *__build_header(struct sk_buff *skb,
66 struct tnl_ptk_info tpi;
67 const struct ovs_key_ipv4_tunnel *tun_key;
69 tun_key = &OVS_CB(skb)->egress_tun_info->tunnel;
71 skb = gre_handle_offloads(skb, !!(tun_key->tun_flags & TUNNEL_CSUM));
75 tpi.flags = filter_tnl_flags(tun_key->tun_flags);
76 tpi.proto = htons(ETH_P_TEB);
77 tpi.key = be64_get_low32(tun_key->tun_id);
79 gre_build_header(skb, &tpi, tunnel_hlen);
84 static __be64 key_to_tunnel_id(__be32 key, __be32 seq)
87 return (__force __be64)((__force u64)seq << 32 | (__force u32)key);
89 return (__force __be64)((__force u64)key << 32 | (__force u32)seq);
93 /* Called with rcu_read_lock and BH disabled. */
94 static int gre_rcv(struct sk_buff *skb,
95 const struct tnl_ptk_info *tpi)
97 struct ovs_tunnel_info tun_info;
98 struct ovs_net *ovs_net;
102 ovs_net = net_generic(dev_net(skb->dev), ovs_net_id);
103 vport = rcu_dereference(ovs_net->vport_net.gre_vport);
104 if (unlikely(!vport))
105 return PACKET_REJECT;
107 key = key_to_tunnel_id(tpi->key, tpi->seq);
108 ovs_flow_tun_info_init(&tun_info, ip_hdr(skb), key,
109 filter_tnl_flags(tpi->flags), NULL, 0);
111 ovs_vport_receive(vport, skb, &tun_info);
115 /* Called with rcu_read_lock and BH disabled. */
116 static int gre_err(struct sk_buff *skb, u32 info,
117 const struct tnl_ptk_info *tpi)
119 struct ovs_net *ovs_net;
122 ovs_net = net_generic(dev_net(skb->dev), ovs_net_id);
123 vport = rcu_dereference(ovs_net->vport_net.gre_vport);
125 if (unlikely(!vport))
126 return PACKET_REJECT;
131 static int gre_tnl_send(struct vport *vport, struct sk_buff *skb)
133 struct net *net = ovs_dp_get_net(vport->dp);
134 struct ovs_key_ipv4_tunnel *tun_key;
142 if (unlikely(!OVS_CB(skb)->egress_tun_info)) {
147 tun_key = &OVS_CB(skb)->egress_tun_info->tunnel;
149 memset(&fl, 0, sizeof(fl));
150 fl.daddr = tun_key->ipv4_dst;
151 fl.saddr = tun_key->ipv4_src;
152 fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
153 fl.flowi4_mark = skb->mark;
154 fl.flowi4_proto = IPPROTO_GRE;
156 rt = ip_route_output_key(net, &fl);
160 tunnel_hlen = ip_gre_calc_hlen(tun_key->tun_flags);
162 min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
163 + tunnel_hlen + sizeof(struct iphdr)
164 + (vlan_tx_tag_present(skb) ? VLAN_HLEN : 0);
165 if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) {
166 int head_delta = SKB_DATA_ALIGN(min_headroom -
169 err = pskb_expand_head(skb, max_t(int, head_delta, 0),
175 if (vlan_tx_tag_present(skb)) {
176 if (unlikely(!__vlan_put_tag(skb,
178 vlan_tx_tag_get(skb)))) {
185 /* Push Tunnel header. */
186 skb = __build_header(skb, tunnel_hlen);
187 if (unlikely(!skb)) {
192 df = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ?
197 return iptunnel_xmit(skb->sk, rt, skb, fl.saddr,
198 tun_key->ipv4_dst, IPPROTO_GRE,
199 tun_key->ipv4_tos, tun_key->ipv4_ttl, df, false);
206 static struct gre_cisco_protocol gre_protocol = {
208 .err_handler = gre_err,
212 static int gre_ports;
213 static int gre_init(void)
221 err = gre_cisco_register(&gre_protocol);
223 pr_warn("cannot register gre protocol handler\n");
228 static void gre_exit(void)
234 gre_cisco_unregister(&gre_protocol);
237 static const char *gre_get_name(const struct vport *vport)
239 return vport_priv(vport);
242 static struct vport *gre_create(const struct vport_parms *parms)
244 struct net *net = ovs_dp_get_net(parms->dp);
245 struct ovs_net *ovs_net;
253 ovs_net = net_generic(net, ovs_net_id);
254 if (ovsl_dereference(ovs_net->vport_net.gre_vport)) {
255 vport = ERR_PTR(-EEXIST);
259 vport = ovs_vport_alloc(IFNAMSIZ, &ovs_gre_vport_ops, parms);
263 strncpy(vport_priv(vport), parms->name, IFNAMSIZ);
264 rcu_assign_pointer(ovs_net->vport_net.gre_vport, vport);
272 static void gre_tnl_destroy(struct vport *vport)
274 struct net *net = ovs_dp_get_net(vport->dp);
275 struct ovs_net *ovs_net;
277 ovs_net = net_generic(net, ovs_net_id);
279 RCU_INIT_POINTER(ovs_net->vport_net.gre_vport, NULL);
280 ovs_vport_deferred_free(vport);
284 const struct vport_ops ovs_gre_vport_ops = {
285 .type = OVS_VPORT_TYPE_GRE,
286 .create = gre_create,
287 .destroy = gre_tnl_destroy,
288 .get_name = gre_get_name,
289 .send = gre_tnl_send,