blob: 065cd94c640c0c2a20cbf99c31cba588db54897e [file] [log] [blame]
Andy Zhou0b5e8b82014-10-03 15:35:28 -07001/*
2 * Geneve: Generic Network Virtualization Encapsulation
3 *
4 * Copyright (c) 2014 Nicira, Inc.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/kernel.h>
15#include <linux/types.h>
16#include <linux/module.h>
17#include <linux/errno.h>
18#include <linux/slab.h>
19#include <linux/skbuff.h>
20#include <linux/rculist.h>
21#include <linux/netdevice.h>
22#include <linux/in.h>
23#include <linux/ip.h>
24#include <linux/udp.h>
25#include <linux/igmp.h>
26#include <linux/etherdevice.h>
27#include <linux/if_ether.h>
28#include <linux/if_vlan.h>
29#include <linux/hash.h>
30#include <linux/ethtool.h>
31#include <net/arp.h>
32#include <net/ndisc.h>
33#include <net/ip.h>
34#include <net/ip_tunnels.h>
35#include <net/icmp.h>
36#include <net/udp.h>
37#include <net/rtnetlink.h>
38#include <net/route.h>
39#include <net/dsfield.h>
40#include <net/inet_ecn.h>
41#include <net/net_namespace.h>
42#include <net/netns/generic.h>
43#include <net/geneve.h>
44#include <net/protocol.h>
45#include <net/udp_tunnel.h>
46#if IS_ENABLED(CONFIG_IPV6)
47#include <net/ipv6.h>
48#include <net/addrconf.h>
49#include <net/ip6_tunnel.h>
50#include <net/ip6_checksum.h>
51#endif
52
53#define PORT_HASH_BITS 8
54#define PORT_HASH_SIZE (1<<PORT_HASH_BITS)
55
56/* per-network namespace private data for this module */
57struct geneve_net {
58 struct hlist_head sock_list[PORT_HASH_SIZE];
59 spinlock_t sock_lock; /* Protects sock_list */
60};
61
62static int geneve_net_id;
63
64static struct workqueue_struct *geneve_wq;
65
66static inline struct genevehdr *geneve_hdr(const struct sk_buff *skb)
67{
68 return (struct genevehdr *)(udp_hdr(skb) + 1);
69}
70
71static struct hlist_head *gs_head(struct net *net, __be16 port)
72{
73 struct geneve_net *gn = net_generic(net, geneve_net_id);
74
75 return &gn->sock_list[hash_32(ntohs(port), PORT_HASH_BITS)];
76}
77
78/* Find geneve socket based on network namespace and UDP port */
79static struct geneve_sock *geneve_find_sock(struct net *net, __be16 port)
80{
81 struct geneve_sock *gs;
82
83 hlist_for_each_entry_rcu(gs, gs_head(net, port), hlist) {
84 if (inet_sk(gs->sock->sk)->inet_sport == port)
85 return gs;
86 }
87
88 return NULL;
89}
90
91static void geneve_build_header(struct genevehdr *geneveh,
92 __be16 tun_flags, u8 vni[3],
93 u8 options_len, u8 *options)
94{
95 geneveh->ver = GENEVE_VER;
96 geneveh->opt_len = options_len / 4;
97 geneveh->oam = !!(tun_flags & TUNNEL_OAM);
98 geneveh->critical = !!(tun_flags & TUNNEL_CRIT_OPT);
99 geneveh->rsvd1 = 0;
100 memcpy(geneveh->vni, vni, 3);
101 geneveh->proto_type = htons(ETH_P_TEB);
102 geneveh->rsvd2 = 0;
103
104 memcpy(geneveh->options, options, options_len);
105}
106
107/* Transmit a fully formated Geneve frame.
108 *
109 * When calling this function. The skb->data should point
110 * to the geneve header which is fully formed.
111 *
112 * This function will add other UDP tunnel headers.
113 */
114int geneve_xmit_skb(struct geneve_sock *gs, struct rtable *rt,
115 struct sk_buff *skb, __be32 src, __be32 dst, __u8 tos,
116 __u8 ttl, __be16 df, __be16 src_port, __be16 dst_port,
117 __be16 tun_flags, u8 vni[3], u8 opt_len, u8 *opt,
118 bool xnet)
119{
120 struct genevehdr *gnvh;
121 int min_headroom;
122 int err;
123
124 skb = udp_tunnel_handle_offloads(skb, !gs->sock->sk->sk_no_check_tx);
125
126 min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
127 + GENEVE_BASE_HLEN + opt_len + sizeof(struct iphdr)
128 + (vlan_tx_tag_present(skb) ? VLAN_HLEN : 0);
129
130 err = skb_cow_head(skb, min_headroom);
131 if (unlikely(err))
132 return err;
133
134 if (vlan_tx_tag_present(skb)) {
135 if (unlikely(!__vlan_put_tag(skb,
136 skb->vlan_proto,
137 vlan_tx_tag_get(skb)))) {
138 err = -ENOMEM;
139 return err;
140 }
141 skb->vlan_tci = 0;
142 }
143
144 gnvh = (struct genevehdr *)__skb_push(skb, sizeof(*gnvh) + opt_len);
145 geneve_build_header(gnvh, tun_flags, vni, opt_len, opt);
146
147 return udp_tunnel_xmit_skb(gs->sock, rt, skb, src, dst,
148 tos, ttl, df, src_port, dst_port, xnet);
149}
150EXPORT_SYMBOL_GPL(geneve_xmit_skb);
151
152static void geneve_notify_add_rx_port(struct geneve_sock *gs)
153{
154 struct sock *sk = gs->sock->sk;
155 sa_family_t sa_family = sk->sk_family;
156 int err;
157
158 if (sa_family == AF_INET) {
159 err = udp_add_offload(&gs->udp_offloads);
160 if (err)
161 pr_warn("geneve: udp_add_offload failed with status %d\n",
162 err);
163 }
164}
165
166/* Callback from net/ipv4/udp.c to receive packets */
167static int geneve_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
168{
169 struct genevehdr *geneveh;
170 struct geneve_sock *gs;
171 int opts_len;
172
173 /* Need Geneve and inner Ethernet header to be present */
174 if (unlikely(!pskb_may_pull(skb, GENEVE_BASE_HLEN)))
175 goto error;
176
177 /* Return packets with reserved bits set */
178 geneveh = geneve_hdr(skb);
179
180 if (unlikely(geneveh->ver != GENEVE_VER))
181 goto error;
182
183 if (unlikely(geneveh->proto_type != htons(ETH_P_TEB)))
184 goto error;
185
186 opts_len = geneveh->opt_len * 4;
187 if (iptunnel_pull_header(skb, GENEVE_BASE_HLEN + opts_len,
188 htons(ETH_P_TEB)))
189 goto drop;
190
191 gs = rcu_dereference_sk_user_data(sk);
192 if (!gs)
193 goto drop;
194
195 gs->rcv(gs, skb);
196 return 0;
197
198drop:
199 /* Consume bad packet */
200 kfree_skb(skb);
201 return 0;
202
203error:
204 /* Let the UDP layer deal with the skb */
205 return 1;
206}
207
208static void geneve_del_work(struct work_struct *work)
209{
210 struct geneve_sock *gs = container_of(work, struct geneve_sock,
211 del_work);
212
213 udp_tunnel_sock_release(gs->sock);
214 kfree_rcu(gs, rcu);
215}
216
217static struct socket *geneve_create_sock(struct net *net, bool ipv6,
218 __be16 port)
219{
220 struct socket *sock;
221 struct udp_port_cfg udp_conf;
222 int err;
223
224 memset(&udp_conf, 0, sizeof(udp_conf));
225
226 if (ipv6) {
227 udp_conf.family = AF_INET6;
228 } else {
229 udp_conf.family = AF_INET;
Andy Zhou42350dc2014-10-06 13:22:50 -0700230 udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
Andy Zhou0b5e8b82014-10-03 15:35:28 -0700231 }
232
233 udp_conf.local_udp_port = port;
234
235 /* Open UDP socket */
236 err = udp_sock_create(net, &udp_conf, &sock);
237 if (err < 0)
238 return ERR_PTR(err);
239
240 return sock;
241}
242
243/* Create new listen socket if needed */
244static struct geneve_sock *geneve_socket_create(struct net *net, __be16 port,
245 geneve_rcv_t *rcv, void *data,
246 bool ipv6)
247{
248 struct geneve_net *gn = net_generic(net, geneve_net_id);
249 struct geneve_sock *gs;
250 struct socket *sock;
251 struct udp_tunnel_sock_cfg tunnel_cfg;
252
253 gs = kzalloc(sizeof(*gs), GFP_KERNEL);
254 if (!gs)
255 return ERR_PTR(-ENOMEM);
256
257 INIT_WORK(&gs->del_work, geneve_del_work);
258
259 sock = geneve_create_sock(net, ipv6, port);
260 if (IS_ERR(sock)) {
261 kfree(gs);
262 return ERR_CAST(sock);
263 }
264
265 gs->sock = sock;
266 atomic_set(&gs->refcnt, 1);
267 gs->rcv = rcv;
268 gs->rcv_data = data;
269
270 /* Initialize the geneve udp offloads structure */
271 gs->udp_offloads.port = port;
272 gs->udp_offloads.callbacks.gro_receive = NULL;
273 gs->udp_offloads.callbacks.gro_complete = NULL;
274
275 spin_lock(&gn->sock_lock);
276 hlist_add_head_rcu(&gs->hlist, gs_head(net, port));
277 geneve_notify_add_rx_port(gs);
278 spin_unlock(&gn->sock_lock);
279
280 /* Mark socket as an encapsulation socket */
281 tunnel_cfg.sk_user_data = gs;
282 tunnel_cfg.encap_type = 1;
283 tunnel_cfg.encap_rcv = geneve_udp_encap_recv;
284 tunnel_cfg.encap_destroy = NULL;
285 setup_udp_tunnel_sock(net, sock, &tunnel_cfg);
286
287 return gs;
288}
289
290struct geneve_sock *geneve_sock_add(struct net *net, __be16 port,
291 geneve_rcv_t *rcv, void *data,
292 bool no_share, bool ipv6)
293{
294 struct geneve_sock *gs;
295
296 gs = geneve_socket_create(net, port, rcv, data, ipv6);
297 if (!IS_ERR(gs))
298 return gs;
299
300 if (no_share) /* Return error if sharing is not allowed. */
301 return ERR_PTR(-EINVAL);
302
303 gs = geneve_find_sock(net, port);
304 if (gs) {
305 if (gs->rcv == rcv)
306 atomic_inc(&gs->refcnt);
307 else
308 gs = ERR_PTR(-EBUSY);
309 } else {
310 gs = ERR_PTR(-EINVAL);
311 }
312
313 return gs;
314}
315EXPORT_SYMBOL_GPL(geneve_sock_add);
316
317void geneve_sock_release(struct geneve_sock *gs)
318{
319 if (!atomic_dec_and_test(&gs->refcnt))
320 return;
321
322 queue_work(geneve_wq, &gs->del_work);
323}
324EXPORT_SYMBOL_GPL(geneve_sock_release);
325
326static __net_init int geneve_init_net(struct net *net)
327{
328 struct geneve_net *gn = net_generic(net, geneve_net_id);
329 unsigned int h;
330
331 spin_lock_init(&gn->sock_lock);
332
333 for (h = 0; h < PORT_HASH_SIZE; ++h)
334 INIT_HLIST_HEAD(&gn->sock_list[h]);
335
336 return 0;
337}
338
339static struct pernet_operations geneve_net_ops = {
340 .init = geneve_init_net,
341 .exit = NULL,
342 .id = &geneve_net_id,
343 .size = sizeof(struct geneve_net),
344};
345
346static int __init geneve_init_module(void)
347{
348 int rc;
349
350 geneve_wq = alloc_workqueue("geneve", 0, 0);
351 if (!geneve_wq)
352 return -ENOMEM;
353
354 rc = register_pernet_subsys(&geneve_net_ops);
355 if (rc)
356 return rc;
357
358 pr_info("Geneve driver\n");
359
360 return 0;
361}
362late_initcall(geneve_init_module);
363
364static void __exit geneve_cleanup_module(void)
365{
366 destroy_workqueue(geneve_wq);
367}
368module_exit(geneve_cleanup_module);
369
370MODULE_LICENSE("GPL");
371MODULE_AUTHOR("Jesse Gross <jesse@nicira.com>");
372MODULE_DESCRIPTION("Driver for GENEVE encapsulated traffic");
373MODULE_ALIAS_RTNL_LINK("geneve");