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
30static 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 */
37struct geneve_port {
38	struct geneve_sock *gs;
39	char name[IFNAMSIZ];
40};
41
42static LIST_HEAD(geneve_ports);
43
44static inline struct geneve_port *geneve_vport(const struct vport *vport)
45{
46	return vport_priv(vport);
47}
48
49static 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. */
55static 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. */
69static __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
80static 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
106static int geneve_get_options(const struct vport *vport,
107			      struct sk_buff *skb)
108{
109	struct geneve_port *geneve_port = geneve_vport(vport);
110	struct inet_sock *sk = inet_sk(geneve_port->gs->sock->sk);
111
112	if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(sk->inet_sport)))
113		return -EMSGSIZE;
114	return 0;
115}
116
117static 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
126static 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;
167error:
168	return ERR_PTR(err);
169}
170
171static 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_sk(geneve_port->gs->sock->sk)->inet_sport;
178	__be16 sport;
179	struct rtable *rt;
180	struct flowi4 fl;
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	rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_UDP);
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, fl.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
220error:
221	kfree_skb(skb);
222	return err;
223}
224
225static 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
232static 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_sk(geneve_port->gs->sock->sk)->inet_sport;
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
248static 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	.owner          = THIS_MODULE,
256	.get_egress_tun_info	= geneve_get_egress_tun_info,
257};
258
259static int __init ovs_geneve_tnl_init(void)
260{
261	return ovs_vport_ops_register(&ovs_geneve_vport_ops);
262}
263
264static void __exit ovs_geneve_tnl_exit(void)
265{
266	ovs_vport_ops_unregister(&ovs_geneve_vport_ops);
267}
268
269module_init(ovs_geneve_tnl_init);
270module_exit(ovs_geneve_tnl_exit);
271
272MODULE_DESCRIPTION("OVS: Geneve swiching port");
273MODULE_LICENSE("GPL");
274MODULE_ALIAS("vport-type-5");
275