2 * Copyright (c) 2007-2013 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 #ifdef CONFIG_OPENVSWITCH_GRE
20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 #include <linux/skbuff.h>
25 #include <linux/if_tunnel.h>
26 #include <linux/if_vlan.h>
28 #include <linux/if_vlan.h>
30 #include <linux/in_route.h>
31 #include <linux/inetdevice.h>
32 #include <linux/jhash.h>
33 #include <linux/list.h>
34 #include <linux/kernel.h>
35 #include <linux/workqueue.h>
36 #include <linux/rculist.h>
37 #include <net/route.h>
42 #include <net/ip_tunnels.h>
44 #include <net/net_namespace.h>
45 #include <net/netns/generic.h>
46 #include <net/protocol.h>
51 /* Returns the least-significant 32 bits of a __be64. */
52 static __be32
be64_get_low32(__be64 x
)
55 return (__force __be32
)x
;
57 return (__force __be32
)((__force u64
)x
>> 32);
61 static __be16
filter_tnl_flags(__be16 flags
)
63 return flags
& (TUNNEL_CSUM
| TUNNEL_KEY
);
66 static struct sk_buff
*__build_header(struct sk_buff
*skb
,
69 const struct ovs_key_ipv4_tunnel
*tun_key
= OVS_CB(skb
)->tun_key
;
70 struct tnl_ptk_info tpi
;
72 skb
= gre_handle_offloads(skb
, !!(tun_key
->tun_flags
& TUNNEL_CSUM
));
76 tpi
.flags
= filter_tnl_flags(tun_key
->tun_flags
);
77 tpi
.proto
= htons(ETH_P_TEB
);
78 tpi
.key
= be64_get_low32(tun_key
->tun_id
);
80 gre_build_header(skb
, &tpi
, tunnel_hlen
);
85 static __be64
key_to_tunnel_id(__be32 key
, __be32 seq
)
88 return (__force __be64
)((__force u64
)seq
<< 32 | (__force u32
)key
);
90 return (__force __be64
)((__force u64
)key
<< 32 | (__force u32
)seq
);
94 /* Called with rcu_read_lock and BH disabled. */
95 static int gre_rcv(struct sk_buff
*skb
,
96 const struct tnl_ptk_info
*tpi
)
98 struct ovs_key_ipv4_tunnel tun_key
;
99 struct ovs_net
*ovs_net
;
103 ovs_net
= net_generic(dev_net(skb
->dev
), ovs_net_id
);
104 vport
= rcu_dereference(ovs_net
->vport_net
.gre_vport
);
105 if (unlikely(!vport
))
106 return PACKET_REJECT
;
108 key
= key_to_tunnel_id(tpi
->key
, tpi
->seq
);
109 ovs_flow_tun_key_init(&tun_key
, ip_hdr(skb
), key
,
110 filter_tnl_flags(tpi
->flags
));
112 ovs_vport_receive(vport
, skb
, &tun_key
);
116 static int gre_tnl_send(struct vport
*vport
, struct sk_buff
*skb
)
118 struct net
*net
= ovs_dp_get_net(vport
->dp
);
126 if (unlikely(!OVS_CB(skb
)->tun_key
)) {
132 memset(&fl
, 0, sizeof(fl
));
133 fl
.daddr
= OVS_CB(skb
)->tun_key
->ipv4_dst
;
134 fl
.saddr
= OVS_CB(skb
)->tun_key
->ipv4_src
;
135 fl
.flowi4_tos
= RT_TOS(OVS_CB(skb
)->tun_key
->ipv4_tos
);
136 fl
.flowi4_mark
= skb
->mark
;
137 fl
.flowi4_proto
= IPPROTO_GRE
;
139 rt
= ip_route_output_key(net
, &fl
);
143 tunnel_hlen
= ip_gre_calc_hlen(OVS_CB(skb
)->tun_key
->tun_flags
);
145 min_headroom
= LL_RESERVED_SPACE(rt
->dst
.dev
) + rt
->dst
.header_len
146 + tunnel_hlen
+ sizeof(struct iphdr
)
147 + (vlan_tx_tag_present(skb
) ? VLAN_HLEN
: 0);
148 if (skb_headroom(skb
) < min_headroom
|| skb_header_cloned(skb
)) {
149 int head_delta
= SKB_DATA_ALIGN(min_headroom
-
152 err
= pskb_expand_head(skb
, max_t(int, head_delta
, 0),
158 if (vlan_tx_tag_present(skb
)) {
159 if (unlikely(!__vlan_put_tag(skb
,
161 vlan_tx_tag_get(skb
)))) {
168 /* Push Tunnel header. */
169 skb
= __build_header(skb
, tunnel_hlen
);
170 if (unlikely(!skb
)) {
175 df
= OVS_CB(skb
)->tun_key
->tun_flags
& TUNNEL_DONT_FRAGMENT
?
180 return iptunnel_xmit(net
, rt
, skb
, fl
.saddr
,
181 OVS_CB(skb
)->tun_key
->ipv4_dst
, IPPROTO_GRE
,
182 OVS_CB(skb
)->tun_key
->ipv4_tos
,
183 OVS_CB(skb
)->tun_key
->ipv4_ttl
, df
);
190 static struct gre_cisco_protocol gre_protocol
= {
195 static int gre_ports
;
196 static int gre_init(void)
204 err
= gre_cisco_register(&gre_protocol
);
206 pr_warn("cannot register gre protocol handler\n");
211 static void gre_exit(void)
217 gre_cisco_unregister(&gre_protocol
);
220 static const char *gre_get_name(const struct vport
*vport
)
222 return vport_priv(vport
);
225 static struct vport
*gre_create(const struct vport_parms
*parms
)
227 struct net
*net
= ovs_dp_get_net(parms
->dp
);
228 struct ovs_net
*ovs_net
;
236 ovs_net
= net_generic(net
, ovs_net_id
);
237 if (ovsl_dereference(ovs_net
->vport_net
.gre_vport
)) {
238 vport
= ERR_PTR(-EEXIST
);
242 vport
= ovs_vport_alloc(IFNAMSIZ
, &ovs_gre_vport_ops
, parms
);
246 strncpy(vport_priv(vport
), parms
->name
, IFNAMSIZ
);
247 rcu_assign_pointer(ovs_net
->vport_net
.gre_vport
, vport
);
255 static void gre_tnl_destroy(struct vport
*vport
)
257 struct net
*net
= ovs_dp_get_net(vport
->dp
);
258 struct ovs_net
*ovs_net
;
260 ovs_net
= net_generic(net
, ovs_net_id
);
262 rcu_assign_pointer(ovs_net
->vport_net
.gre_vport
, NULL
);
263 ovs_vport_deferred_free(vport
);
267 const struct vport_ops ovs_gre_vport_ops
= {
268 .type
= OVS_VPORT_TYPE_GRE
,
269 .create
= gre_create
,
270 .destroy
= gre_tnl_destroy
,
271 .get_name
= gre_get_name
,
272 .send
= gre_tnl_send
,
275 #endif /* OPENVSWITCH_GRE */