2 * Geneve: Generic Network Virtualization Encapsulation
4 * Copyright (c) 2014 Nicira, Inc.
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.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
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>
32 #include <net/ndisc.h>
34 #include <net/ip_tunnels.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)
48 #include <net/addrconf.h>
49 #include <net/ip6_tunnel.h>
50 #include <net/ip6_checksum.h>
53 #define PORT_HASH_BITS 8
54 #define PORT_HASH_SIZE (1<<PORT_HASH_BITS)
56 /* per-network namespace private data for this module */
58 struct hlist_head sock_list[PORT_HASH_SIZE];
59 spinlock_t sock_lock; /* Protects sock_list */
62 static int geneve_net_id;
64 static struct workqueue_struct *geneve_wq;
66 static inline struct genevehdr *geneve_hdr(const struct sk_buff *skb)
68 return (struct genevehdr *)(udp_hdr(skb) + 1);
71 static struct hlist_head *gs_head(struct net *net, __be16 port)
73 struct geneve_net *gn = net_generic(net, geneve_net_id);
75 return &gn->sock_list[hash_32(ntohs(port), PORT_HASH_BITS)];
78 /* Find geneve socket based on network namespace and UDP port */
79 static struct geneve_sock *geneve_find_sock(struct net *net, __be16 port)
81 struct geneve_sock *gs;
83 hlist_for_each_entry_rcu(gs, gs_head(net, port), hlist) {
84 if (inet_sk(gs->sock->sk)->inet_sport == port)
91 static void geneve_build_header(struct genevehdr *geneveh,
92 __be16 tun_flags, u8 vni[3],
93 u8 options_len, u8 *options)
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);
100 memcpy(geneveh->vni, vni, 3);
101 geneveh->proto_type = htons(ETH_P_TEB);
104 memcpy(geneveh->options, options, options_len);
107 /* Transmit a fully formated Geneve frame.
109 * When calling this function. The skb->data should point
110 * to the geneve header which is fully formed.
112 * This function will add other UDP tunnel headers.
114 int 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,
120 struct genevehdr *gnvh;
124 skb = udp_tunnel_handle_offloads(skb, !gs->sock->sk->sk_no_check_tx);
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);
130 err = skb_cow_head(skb, min_headroom);
134 if (vlan_tx_tag_present(skb)) {
135 if (unlikely(!__vlan_put_tag(skb,
137 vlan_tx_tag_get(skb)))) {
144 gnvh = (struct genevehdr *)__skb_push(skb, sizeof(*gnvh) + opt_len);
145 geneve_build_header(gnvh, tun_flags, vni, opt_len, opt);
147 skb_set_inner_protocol(skb, htons(ETH_P_TEB));
149 return udp_tunnel_xmit_skb(gs->sock, rt, skb, src, dst,
150 tos, ttl, df, src_port, dst_port, xnet);
152 EXPORT_SYMBOL_GPL(geneve_xmit_skb);
154 static void geneve_notify_add_rx_port(struct geneve_sock *gs)
156 struct sock *sk = gs->sock->sk;
157 sa_family_t sa_family = sk->sk_family;
160 if (sa_family == AF_INET) {
161 err = udp_add_offload(&gs->udp_offloads);
163 pr_warn("geneve: udp_add_offload failed with status %d\n",
168 /* Callback from net/ipv4/udp.c to receive packets */
169 static int geneve_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
171 struct genevehdr *geneveh;
172 struct geneve_sock *gs;
175 /* Need Geneve and inner Ethernet header to be present */
176 if (unlikely(!pskb_may_pull(skb, GENEVE_BASE_HLEN)))
179 /* Return packets with reserved bits set */
180 geneveh = geneve_hdr(skb);
182 if (unlikely(geneveh->ver != GENEVE_VER))
185 if (unlikely(geneveh->proto_type != htons(ETH_P_TEB)))
188 opts_len = geneveh->opt_len * 4;
189 if (iptunnel_pull_header(skb, GENEVE_BASE_HLEN + opts_len,
193 gs = rcu_dereference_sk_user_data(sk);
201 /* Consume bad packet */
206 /* Let the UDP layer deal with the skb */
210 static void geneve_del_work(struct work_struct *work)
212 struct geneve_sock *gs = container_of(work, struct geneve_sock,
215 udp_tunnel_sock_release(gs->sock);
219 static struct socket *geneve_create_sock(struct net *net, bool ipv6,
223 struct udp_port_cfg udp_conf;
226 memset(&udp_conf, 0, sizeof(udp_conf));
229 udp_conf.family = AF_INET6;
231 udp_conf.family = AF_INET;
232 udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
235 udp_conf.local_udp_port = port;
237 /* Open UDP socket */
238 err = udp_sock_create(net, &udp_conf, &sock);
245 /* Create new listen socket if needed */
246 static struct geneve_sock *geneve_socket_create(struct net *net, __be16 port,
247 geneve_rcv_t *rcv, void *data,
250 struct geneve_net *gn = net_generic(net, geneve_net_id);
251 struct geneve_sock *gs;
253 struct udp_tunnel_sock_cfg tunnel_cfg;
255 gs = kzalloc(sizeof(*gs), GFP_KERNEL);
257 return ERR_PTR(-ENOMEM);
259 INIT_WORK(&gs->del_work, geneve_del_work);
261 sock = geneve_create_sock(net, ipv6, port);
264 return ERR_CAST(sock);
268 atomic_set(&gs->refcnt, 1);
272 /* Initialize the geneve udp offloads structure */
273 gs->udp_offloads.port = port;
274 gs->udp_offloads.callbacks.gro_receive = NULL;
275 gs->udp_offloads.callbacks.gro_complete = NULL;
277 spin_lock(&gn->sock_lock);
278 hlist_add_head_rcu(&gs->hlist, gs_head(net, port));
279 geneve_notify_add_rx_port(gs);
280 spin_unlock(&gn->sock_lock);
282 /* Mark socket as an encapsulation socket */
283 tunnel_cfg.sk_user_data = gs;
284 tunnel_cfg.encap_type = 1;
285 tunnel_cfg.encap_rcv = geneve_udp_encap_recv;
286 tunnel_cfg.encap_destroy = NULL;
287 setup_udp_tunnel_sock(net, sock, &tunnel_cfg);
292 struct geneve_sock *geneve_sock_add(struct net *net, __be16 port,
293 geneve_rcv_t *rcv, void *data,
294 bool no_share, bool ipv6)
296 struct geneve_sock *gs;
298 gs = geneve_socket_create(net, port, rcv, data, ipv6);
302 if (no_share) /* Return error if sharing is not allowed. */
303 return ERR_PTR(-EINVAL);
305 gs = geneve_find_sock(net, port);
308 atomic_inc(&gs->refcnt);
310 gs = ERR_PTR(-EBUSY);
312 gs = ERR_PTR(-EINVAL);
317 EXPORT_SYMBOL_GPL(geneve_sock_add);
319 void geneve_sock_release(struct geneve_sock *gs)
321 if (!atomic_dec_and_test(&gs->refcnt))
324 queue_work(geneve_wq, &gs->del_work);
326 EXPORT_SYMBOL_GPL(geneve_sock_release);
328 static __net_init int geneve_init_net(struct net *net)
330 struct geneve_net *gn = net_generic(net, geneve_net_id);
333 spin_lock_init(&gn->sock_lock);
335 for (h = 0; h < PORT_HASH_SIZE; ++h)
336 INIT_HLIST_HEAD(&gn->sock_list[h]);
341 static struct pernet_operations geneve_net_ops = {
342 .init = geneve_init_net,
344 .id = &geneve_net_id,
345 .size = sizeof(struct geneve_net),
348 static int __init geneve_init_module(void)
352 geneve_wq = alloc_workqueue("geneve", 0, 0);
356 rc = register_pernet_subsys(&geneve_net_ops);
360 pr_info("Geneve driver\n");
364 late_initcall(geneve_init_module);
366 static void __exit geneve_cleanup_module(void)
368 destroy_workqueue(geneve_wq);
369 unregister_pernet_subsys(&geneve_net_ops);
371 module_exit(geneve_cleanup_module);
373 MODULE_LICENSE("GPL");
374 MODULE_AUTHOR("Jesse Gross <jesse@nicira.com>");
375 MODULE_DESCRIPTION("Driver for GENEVE encapsulated traffic");
376 MODULE_ALIAS_RTNL_LINK("geneve");