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;
34 struct udp_port_cfg udp_config;
37 static inline struct fou *fou_from_sock(struct sock *sk)
39 return sk->sk_user_data;
42 static int fou_udp_encap_recv_deliver(struct sk_buff *skb,
43 u8 protocol, size_t len)
45 struct iphdr *iph = ip_hdr(skb);
47 /* Remove 'len' bytes from the packet (UDP header and
48 * FOU header if present), modify the protocol to the one
49 * we found, and then call rcv_encap.
51 iph->tot_len = htons(ntohs(iph->tot_len) - len);
53 skb_postpull_rcsum(skb, udp_hdr(skb), len);
54 skb_reset_transport_header(skb);
59 static int fou_udp_recv(struct sock *sk, struct sk_buff *skb)
61 struct fou *fou = fou_from_sock(sk);
66 return fou_udp_encap_recv_deliver(skb, fou->protocol,
67 sizeof(struct udphdr));
70 static int gue_udp_recv(struct sock *sk, struct sk_buff *skb)
72 struct fou *fou = fou_from_sock(sk);
74 struct guehdr *guehdr;
80 len = sizeof(struct udphdr) + sizeof(struct guehdr);
81 if (!pskb_may_pull(skb, len))
85 guehdr = (struct guehdr *)&uh[1];
87 len += guehdr->hlen << 2;
88 if (!pskb_may_pull(skb, len))
92 guehdr = (struct guehdr *)&uh[1];
94 if (guehdr->version != 0)
102 return fou_udp_encap_recv_deliver(skb, guehdr->next_hdr, len);
108 static struct sk_buff **fou_gro_receive(struct sk_buff **head,
111 const struct net_offload *ops;
112 struct sk_buff **pp = NULL;
113 u8 proto = NAPI_GRO_CB(skb)->proto;
114 const struct net_offload **offloads;
117 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
118 ops = rcu_dereference(offloads[proto]);
119 if (!ops || !ops->callbacks.gro_receive)
122 pp = ops->callbacks.gro_receive(head, skb);
130 static int fou_gro_complete(struct sk_buff *skb, int nhoff)
132 const struct net_offload *ops;
133 u8 proto = NAPI_GRO_CB(skb)->proto;
135 const struct net_offload **offloads;
137 udp_tunnel_gro_complete(skb, nhoff);
140 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
141 ops = rcu_dereference(offloads[proto]);
142 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
145 err = ops->callbacks.gro_complete(skb, nhoff);
153 static struct sk_buff **gue_gro_receive(struct sk_buff **head,
156 const struct net_offload **offloads;
157 const struct net_offload *ops;
158 struct sk_buff **pp = NULL;
161 struct guehdr *guehdr;
162 unsigned int hlen, guehlen;
166 off = skb_gro_offset(skb);
167 hlen = off + sizeof(*guehdr);
168 guehdr = skb_gro_header_fast(skb, off);
169 if (skb_gro_header_hard(skb, hlen)) {
170 guehdr = skb_gro_header_slow(skb, hlen, off);
171 if (unlikely(!guehdr))
175 proto = guehdr->next_hdr;
178 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
179 ops = rcu_dereference(offloads[proto]);
180 if (WARN_ON(!ops || !ops->callbacks.gro_receive))
183 guehlen = sizeof(*guehdr) + (guehdr->hlen << 2);
185 hlen = off + guehlen;
186 if (skb_gro_header_hard(skb, hlen)) {
187 guehdr = skb_gro_header_slow(skb, hlen, off);
188 if (unlikely(!guehdr))
194 for (p = *head; p; p = p->next) {
195 const struct guehdr *guehdr2;
197 if (!NAPI_GRO_CB(p)->same_flow)
200 guehdr2 = (struct guehdr *)(p->data + off);
202 /* Compare base GUE header to be equal (covers
203 * hlen, version, next_hdr, and flags.
205 if (guehdr->word != guehdr2->word) {
206 NAPI_GRO_CB(p)->same_flow = 0;
210 /* Compare optional fields are the same. */
211 if (guehdr->hlen && memcmp(&guehdr[1], &guehdr2[1],
212 guehdr->hlen << 2)) {
213 NAPI_GRO_CB(p)->same_flow = 0;
218 skb_gro_pull(skb, guehlen);
220 /* Adjusted NAPI_GRO_CB(skb)->csum after skb_gro_pull()*/
221 skb_gro_postpull_rcsum(skb, guehdr, guehlen);
223 pp = ops->callbacks.gro_receive(head, skb);
228 NAPI_GRO_CB(skb)->flush |= flush;
233 static int gue_gro_complete(struct sk_buff *skb, int nhoff)
235 const struct net_offload **offloads;
236 struct guehdr *guehdr = (struct guehdr *)(skb->data + nhoff);
237 const struct net_offload *ops;
238 unsigned int guehlen;
242 proto = guehdr->next_hdr;
244 guehlen = sizeof(*guehdr) + (guehdr->hlen << 2);
247 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
248 ops = rcu_dereference(offloads[proto]);
249 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
252 err = ops->callbacks.gro_complete(skb, nhoff + guehlen);
259 static int fou_add_to_port_list(struct fou *fou)
263 spin_lock(&fou_lock);
264 list_for_each_entry(fout, &fou_list, list) {
265 if (fou->port == fout->port) {
266 spin_unlock(&fou_lock);
271 list_add(&fou->list, &fou_list);
272 spin_unlock(&fou_lock);
277 static void fou_release(struct fou *fou)
279 struct socket *sock = fou->sock;
280 struct sock *sk = sock->sk;
282 udp_del_offload(&fou->udp_offloads);
284 list_del(&fou->list);
286 /* Remove hooks into tunnel socket */
287 sk->sk_user_data = NULL;
294 static int fou_encap_init(struct sock *sk, struct fou *fou, struct fou_cfg *cfg)
296 udp_sk(sk)->encap_rcv = fou_udp_recv;
297 fou->protocol = cfg->protocol;
298 fou->udp_offloads.callbacks.gro_receive = fou_gro_receive;
299 fou->udp_offloads.callbacks.gro_complete = fou_gro_complete;
300 fou->udp_offloads.port = cfg->udp_config.local_udp_port;
301 fou->udp_offloads.ipproto = cfg->protocol;
306 static int gue_encap_init(struct sock *sk, struct fou *fou, struct fou_cfg *cfg)
308 udp_sk(sk)->encap_rcv = gue_udp_recv;
309 fou->udp_offloads.callbacks.gro_receive = gue_gro_receive;
310 fou->udp_offloads.callbacks.gro_complete = gue_gro_complete;
311 fou->udp_offloads.port = cfg->udp_config.local_udp_port;
316 static int fou_create(struct net *net, struct fou_cfg *cfg,
317 struct socket **sockp)
319 struct fou *fou = NULL;
321 struct socket *sock = NULL;
324 /* Open UDP socket */
325 err = udp_sock_create(net, &cfg->udp_config, &sock);
329 /* Allocate FOU port structure */
330 fou = kzalloc(sizeof(*fou), GFP_KERNEL);
338 fou->port = cfg->udp_config.local_udp_port;
340 /* Initial for fou type */
342 case FOU_ENCAP_DIRECT:
343 err = fou_encap_init(sk, fou, cfg);
348 err = gue_encap_init(sk, fou, cfg);
357 udp_sk(sk)->encap_type = 1;
360 sk->sk_user_data = fou;
363 udp_set_convert_csum(sk, true);
365 sk->sk_allocation = GFP_ATOMIC;
367 if (cfg->udp_config.family == AF_INET) {
368 err = udp_add_offload(&fou->udp_offloads);
373 err = fou_add_to_port_list(fou);
390 static int fou_destroy(struct net *net, struct fou_cfg *cfg)
393 u16 port = cfg->udp_config.local_udp_port;
396 spin_lock(&fou_lock);
397 list_for_each_entry(fou, &fou_list, list) {
398 if (fou->port == port) {
399 udp_del_offload(&fou->udp_offloads);
405 spin_unlock(&fou_lock);
410 static struct genl_family fou_nl_family = {
411 .id = GENL_ID_GENERATE,
413 .name = FOU_GENL_NAME,
414 .version = FOU_GENL_VERSION,
415 .maxattr = FOU_ATTR_MAX,
419 static struct nla_policy fou_nl_policy[FOU_ATTR_MAX + 1] = {
420 [FOU_ATTR_PORT] = { .type = NLA_U16, },
421 [FOU_ATTR_AF] = { .type = NLA_U8, },
422 [FOU_ATTR_IPPROTO] = { .type = NLA_U8, },
423 [FOU_ATTR_TYPE] = { .type = NLA_U8, },
426 static int parse_nl_config(struct genl_info *info,
429 memset(cfg, 0, sizeof(*cfg));
431 cfg->udp_config.family = AF_INET;
433 if (info->attrs[FOU_ATTR_AF]) {
434 u8 family = nla_get_u8(info->attrs[FOU_ATTR_AF]);
436 if (family != AF_INET && family != AF_INET6)
439 cfg->udp_config.family = family;
442 if (info->attrs[FOU_ATTR_PORT]) {
443 u16 port = nla_get_u16(info->attrs[FOU_ATTR_PORT]);
445 cfg->udp_config.local_udp_port = port;
448 if (info->attrs[FOU_ATTR_IPPROTO])
449 cfg->protocol = nla_get_u8(info->attrs[FOU_ATTR_IPPROTO]);
451 if (info->attrs[FOU_ATTR_TYPE])
452 cfg->type = nla_get_u8(info->attrs[FOU_ATTR_TYPE]);
457 static int fou_nl_cmd_add_port(struct sk_buff *skb, struct genl_info *info)
462 err = parse_nl_config(info, &cfg);
466 return fou_create(&init_net, &cfg, NULL);
469 static int fou_nl_cmd_rm_port(struct sk_buff *skb, struct genl_info *info)
473 parse_nl_config(info, &cfg);
475 return fou_destroy(&init_net, &cfg);
478 static const struct genl_ops fou_nl_ops[] = {
481 .doit = fou_nl_cmd_add_port,
482 .policy = fou_nl_policy,
483 .flags = GENL_ADMIN_PERM,
487 .doit = fou_nl_cmd_rm_port,
488 .policy = fou_nl_policy,
489 .flags = GENL_ADMIN_PERM,
493 static int __init fou_init(void)
497 ret = genl_register_family_with_ops(&fou_nl_family,
503 static void __exit fou_fini(void)
505 struct fou *fou, *next;
507 genl_unregister_family(&fou_nl_family);
509 /* Close all the FOU sockets */
511 spin_lock(&fou_lock);
512 list_for_each_entry_safe(fou, next, &fou_list, list)
514 spin_unlock(&fou_lock);
517 module_init(fou_init);
518 module_exit(fou_fini);
519 MODULE_AUTHOR("Tom Herbert <therbert@google.com>");
520 MODULE_LICENSE("GPL");