1 #include <linux/module.h>
2 #include <linux/errno.h>
3 #include <linux/socket.h>
4 #include <linux/skbuff.h>
7 #include <linux/types.h>
8 #include <linux/kernel.h>
9 #include <net/genetlink.h>
12 #include <net/protocol.h>
14 #include <net/udp_tunnel.h>
16 #include <uapi/linux/fou.h>
17 #include <uapi/linux/genetlink.h>
19 static DEFINE_SPINLOCK(fou_lock);
20 static LIST_HEAD(fou_list);
26 struct udp_offload udp_offloads;
27 struct list_head list;
33 struct udp_port_cfg udp_config;
36 static inline struct fou *fou_from_sock(struct sock *sk)
38 return sk->sk_user_data;
41 static int fou_udp_encap_recv_deliver(struct sk_buff *skb,
42 u8 protocol, size_t len)
44 struct iphdr *iph = ip_hdr(skb);
46 /* Remove 'len' bytes from the packet (UDP header and
47 * FOU header if present), modify the protocol to the one
48 * we found, and then call rcv_encap.
50 iph->tot_len = htons(ntohs(iph->tot_len) - len);
52 skb_postpull_rcsum(skb, udp_hdr(skb), len);
53 skb_reset_transport_header(skb);
58 static int fou_udp_recv(struct sock *sk, struct sk_buff *skb)
60 struct fou *fou = fou_from_sock(sk);
65 return fou_udp_encap_recv_deliver(skb, fou->protocol,
66 sizeof(struct udphdr));
69 static int gue_udp_recv(struct sock *sk, struct sk_buff *skb)
71 struct fou *fou = fou_from_sock(sk);
73 struct guehdr *guehdr;
79 len = sizeof(struct udphdr) + sizeof(struct guehdr);
80 if (!pskb_may_pull(skb, len))
84 guehdr = (struct guehdr *)&uh[1];
86 len += guehdr->hlen << 2;
87 if (!pskb_may_pull(skb, len))
91 guehdr = (struct guehdr *)&uh[1];
93 if (guehdr->version != 0)
101 return fou_udp_encap_recv_deliver(skb, guehdr->next_hdr, len);
107 static struct sk_buff **fou_gro_receive(struct sk_buff **head,
110 const struct net_offload *ops;
111 struct sk_buff **pp = NULL;
112 u8 proto = NAPI_GRO_CB(skb)->proto;
113 const struct net_offload **offloads;
116 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
117 ops = rcu_dereference(offloads[proto]);
118 if (!ops || !ops->callbacks.gro_receive)
121 pp = ops->callbacks.gro_receive(head, skb);
129 static int fou_gro_complete(struct sk_buff *skb, int nhoff)
131 const struct net_offload *ops;
132 u8 proto = NAPI_GRO_CB(skb)->proto;
134 const struct net_offload **offloads;
136 udp_tunnel_gro_complete(skb, nhoff);
139 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
140 ops = rcu_dereference(offloads[proto]);
141 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
144 err = ops->callbacks.gro_complete(skb, nhoff);
152 static struct sk_buff **gue_gro_receive(struct sk_buff **head,
155 const struct net_offload **offloads;
156 const struct net_offload *ops;
157 struct sk_buff **pp = NULL;
160 struct guehdr *guehdr;
161 unsigned int hlen, guehlen;
165 off = skb_gro_offset(skb);
166 hlen = off + sizeof(*guehdr);
167 guehdr = skb_gro_header_fast(skb, off);
168 if (skb_gro_header_hard(skb, hlen)) {
169 guehdr = skb_gro_header_slow(skb, hlen, off);
170 if (unlikely(!guehdr))
174 proto = guehdr->next_hdr;
177 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
178 ops = rcu_dereference(offloads[proto]);
179 if (WARN_ON(!ops || !ops->callbacks.gro_receive))
182 guehlen = sizeof(*guehdr) + (guehdr->hlen << 2);
184 hlen = off + guehlen;
185 if (skb_gro_header_hard(skb, hlen)) {
186 guehdr = skb_gro_header_slow(skb, hlen, off);
187 if (unlikely(!guehdr))
193 for (p = *head; p; p = p->next) {
194 const struct guehdr *guehdr2;
196 if (!NAPI_GRO_CB(p)->same_flow)
199 guehdr2 = (struct guehdr *)(p->data + off);
201 /* Compare base GUE header to be equal (covers
202 * hlen, version, next_hdr, and flags.
204 if (guehdr->word != guehdr2->word) {
205 NAPI_GRO_CB(p)->same_flow = 0;
209 /* Compare optional fields are the same. */
210 if (guehdr->hlen && memcmp(&guehdr[1], &guehdr2[1],
211 guehdr->hlen << 2)) {
212 NAPI_GRO_CB(p)->same_flow = 0;
217 skb_gro_pull(skb, guehlen);
219 /* Adjusted NAPI_GRO_CB(skb)->csum after skb_gro_pull()*/
220 skb_gro_postpull_rcsum(skb, guehdr, guehlen);
222 pp = ops->callbacks.gro_receive(head, skb);
227 NAPI_GRO_CB(skb)->flush |= flush;
232 static int gue_gro_complete(struct sk_buff *skb, int nhoff)
234 const struct net_offload **offloads;
235 struct guehdr *guehdr = (struct guehdr *)(skb->data + nhoff);
236 const struct net_offload *ops;
237 unsigned int guehlen;
241 proto = guehdr->next_hdr;
243 guehlen = sizeof(*guehdr) + (guehdr->hlen << 2);
246 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
247 ops = rcu_dereference(offloads[proto]);
248 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
251 err = ops->callbacks.gro_complete(skb, nhoff + guehlen);
258 static int fou_add_to_port_list(struct fou *fou)
262 spin_lock(&fou_lock);
263 list_for_each_entry(fout, &fou_list, list) {
264 if (fou->port == fout->port) {
265 spin_unlock(&fou_lock);
270 list_add(&fou->list, &fou_list);
271 spin_unlock(&fou_lock);
276 static void fou_release(struct fou *fou)
278 struct socket *sock = fou->sock;
279 struct sock *sk = sock->sk;
281 udp_del_offload(&fou->udp_offloads);
283 list_del(&fou->list);
285 /* Remove hooks into tunnel socket */
286 sk->sk_user_data = NULL;
293 static int fou_encap_init(struct sock *sk, struct fou *fou, struct fou_cfg *cfg)
295 udp_sk(sk)->encap_rcv = fou_udp_recv;
296 fou->protocol = cfg->protocol;
297 fou->udp_offloads.callbacks.gro_receive = fou_gro_receive;
298 fou->udp_offloads.callbacks.gro_complete = fou_gro_complete;
299 fou->udp_offloads.port = cfg->udp_config.local_udp_port;
300 fou->udp_offloads.ipproto = cfg->protocol;
305 static int gue_encap_init(struct sock *sk, struct fou *fou, struct fou_cfg *cfg)
307 udp_sk(sk)->encap_rcv = gue_udp_recv;
308 fou->udp_offloads.callbacks.gro_receive = gue_gro_receive;
309 fou->udp_offloads.callbacks.gro_complete = gue_gro_complete;
310 fou->udp_offloads.port = cfg->udp_config.local_udp_port;
315 static int fou_create(struct net *net, struct fou_cfg *cfg,
316 struct socket **sockp)
318 struct fou *fou = NULL;
320 struct socket *sock = NULL;
323 /* Open UDP socket */
324 err = udp_sock_create(net, &cfg->udp_config, &sock);
328 /* Allocate FOU port structure */
329 fou = kzalloc(sizeof(*fou), GFP_KERNEL);
337 fou->port = cfg->udp_config.local_udp_port;
339 /* Initial for fou type */
341 case FOU_ENCAP_DIRECT:
342 err = fou_encap_init(sk, fou, cfg);
347 err = gue_encap_init(sk, fou, cfg);
356 udp_sk(sk)->encap_type = 1;
359 sk->sk_user_data = fou;
362 udp_set_convert_csum(sk, true);
364 sk->sk_allocation = GFP_ATOMIC;
366 if (cfg->udp_config.family == AF_INET) {
367 err = udp_add_offload(&fou->udp_offloads);
372 err = fou_add_to_port_list(fou);
389 static int fou_destroy(struct net *net, struct fou_cfg *cfg)
392 u16 port = cfg->udp_config.local_udp_port;
395 spin_lock(&fou_lock);
396 list_for_each_entry(fou, &fou_list, list) {
397 if (fou->port == port) {
398 udp_del_offload(&fou->udp_offloads);
404 spin_unlock(&fou_lock);
409 static struct genl_family fou_nl_family = {
410 .id = GENL_ID_GENERATE,
412 .name = FOU_GENL_NAME,
413 .version = FOU_GENL_VERSION,
414 .maxattr = FOU_ATTR_MAX,
418 static struct nla_policy fou_nl_policy[FOU_ATTR_MAX + 1] = {
419 [FOU_ATTR_PORT] = { .type = NLA_U16, },
420 [FOU_ATTR_AF] = { .type = NLA_U8, },
421 [FOU_ATTR_IPPROTO] = { .type = NLA_U8, },
422 [FOU_ATTR_TYPE] = { .type = NLA_U8, },
425 static int parse_nl_config(struct genl_info *info,
428 memset(cfg, 0, sizeof(*cfg));
430 cfg->udp_config.family = AF_INET;
432 if (info->attrs[FOU_ATTR_AF]) {
433 u8 family = nla_get_u8(info->attrs[FOU_ATTR_AF]);
435 if (family != AF_INET && family != AF_INET6)
438 cfg->udp_config.family = family;
441 if (info->attrs[FOU_ATTR_PORT]) {
442 u16 port = nla_get_u16(info->attrs[FOU_ATTR_PORT]);
444 cfg->udp_config.local_udp_port = port;
447 if (info->attrs[FOU_ATTR_IPPROTO])
448 cfg->protocol = nla_get_u8(info->attrs[FOU_ATTR_IPPROTO]);
450 if (info->attrs[FOU_ATTR_TYPE])
451 cfg->type = nla_get_u8(info->attrs[FOU_ATTR_TYPE]);
456 static int fou_nl_cmd_add_port(struct sk_buff *skb, struct genl_info *info)
461 err = parse_nl_config(info, &cfg);
465 return fou_create(&init_net, &cfg, NULL);
468 static int fou_nl_cmd_rm_port(struct sk_buff *skb, struct genl_info *info)
472 parse_nl_config(info, &cfg);
474 return fou_destroy(&init_net, &cfg);
477 static const struct genl_ops fou_nl_ops[] = {
480 .doit = fou_nl_cmd_add_port,
481 .policy = fou_nl_policy,
482 .flags = GENL_ADMIN_PERM,
486 .doit = fou_nl_cmd_rm_port,
487 .policy = fou_nl_policy,
488 .flags = GENL_ADMIN_PERM,
492 static int __init fou_init(void)
496 ret = genl_register_family_with_ops(&fou_nl_family,
502 static void __exit fou_fini(void)
504 struct fou *fou, *next;
506 genl_unregister_family(&fou_nl_family);
508 /* Close all the FOU sockets */
510 spin_lock(&fou_lock);
511 list_for_each_entry_safe(fou, next, &fou_list, list)
513 spin_unlock(&fou_lock);
516 module_init(fou_init);
517 module_exit(fou_fini);
518 MODULE_AUTHOR("Tom Herbert <therbert@google.com>");
519 MODULE_LICENSE("GPL");