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1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/module.h>
3#include <linux/errno.h>
4#include <linux/socket.h>
5#include <linux/skbuff.h>
6#include <linux/ip.h>
7#include <linux/icmp.h>
8#include <linux/udp.h>
9#include <linux/types.h>
10#include <linux/kernel.h>
11#include <net/genetlink.h>
12#include <net/gue.h>
13#include <net/fou.h>
14#include <net/ip.h>
15#include <net/protocol.h>
16#include <net/udp.h>
17#include <net/udp_tunnel.h>
18#include <net/xfrm.h>
19#include <uapi/linux/fou.h>
20#include <uapi/linux/genetlink.h>
21
22struct fou {
23 struct socket *sock;
24 u8 protocol;
25 u8 flags;
26 __be16 port;
27 u8 family;
28 u16 type;
29 struct list_head list;
30 struct rcu_head rcu;
31};
32
33#define FOU_F_REMCSUM_NOPARTIAL BIT(0)
34
35struct fou_cfg {
36 u16 type;
37 u8 protocol;
38 u8 flags;
39 struct udp_port_cfg udp_config;
40};
41
42static unsigned int fou_net_id;
43
44struct fou_net {
45 struct list_head fou_list;
46 struct mutex fou_lock;
47};
48
49static inline struct fou *fou_from_sock(struct sock *sk)
50{
51 return sk->sk_user_data;
52}
53
54static int fou_recv_pull(struct sk_buff *skb, struct fou *fou, size_t len)
55{
56 /* Remove 'len' bytes from the packet (UDP header and
57 * FOU header if present).
58 */
59 if (fou->family == AF_INET)
60 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len);
61 else
62 ipv6_hdr(skb)->payload_len =
63 htons(ntohs(ipv6_hdr(skb)->payload_len) - len);
64
65 __skb_pull(skb, len);
66 skb_postpull_rcsum(skb, udp_hdr(skb), len);
67 skb_reset_transport_header(skb);
68 return iptunnel_pull_offloads(skb);
69}
70
71static int fou_udp_recv(struct sock *sk, struct sk_buff *skb)
72{
73 struct fou *fou = fou_from_sock(sk);
74
75 if (!fou)
76 return 1;
77
78 if (fou_recv_pull(skb, fou, sizeof(struct udphdr)))
79 goto drop;
80
81 return -fou->protocol;
82
83drop:
84 kfree_skb(skb);
85 return 0;
86}
87
88static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr,
89 void *data, size_t hdrlen, u8 ipproto,
90 bool nopartial)
91{
92 __be16 *pd = data;
93 size_t start = ntohs(pd[0]);
94 size_t offset = ntohs(pd[1]);
95 size_t plen = sizeof(struct udphdr) + hdrlen +
96 max_t(size_t, offset + sizeof(u16), start);
97
98 if (skb->remcsum_offload)
99 return guehdr;
100
101 if (!pskb_may_pull(skb, plen))
102 return NULL;
103 guehdr = (struct guehdr *)&udp_hdr(skb)[1];
104
105 skb_remcsum_process(skb, (void *)guehdr + hdrlen,
106 start, offset, nopartial);
107
108 return guehdr;
109}
110
111static int gue_control_message(struct sk_buff *skb, struct guehdr *guehdr)
112{
113 /* No support yet */
114 kfree_skb(skb);
115 return 0;
116}
117
118static int gue_udp_recv(struct sock *sk, struct sk_buff *skb)
119{
120 struct fou *fou = fou_from_sock(sk);
121 size_t len, optlen, hdrlen;
122 struct guehdr *guehdr;
123 void *data;
124 u16 doffset = 0;
125 u8 proto_ctype;
126
127 if (!fou)
128 return 1;
129
130 len = sizeof(struct udphdr) + sizeof(struct guehdr);
131 if (!pskb_may_pull(skb, len))
132 goto drop;
133
134 guehdr = (struct guehdr *)&udp_hdr(skb)[1];
135
136 switch (guehdr->version) {
137 case 0: /* Full GUE header present */
138 break;
139
140 case 1: {
141 /* Direct encapsulation of IPv4 or IPv6 */
142
143 int prot;
144
145 switch (((struct iphdr *)guehdr)->version) {
146 case 4:
147 prot = IPPROTO_IPIP;
148 break;
149 case 6:
150 prot = IPPROTO_IPV6;
151 break;
152 default:
153 goto drop;
154 }
155
156 if (fou_recv_pull(skb, fou, sizeof(struct udphdr)))
157 goto drop;
158
159 return -prot;
160 }
161
162 default: /* Undefined version */
163 goto drop;
164 }
165
166 optlen = guehdr->hlen << 2;
167 len += optlen;
168
169 if (!pskb_may_pull(skb, len))
170 goto drop;
171
172 /* guehdr may change after pull */
173 guehdr = (struct guehdr *)&udp_hdr(skb)[1];
174
175 if (validate_gue_flags(guehdr, optlen))
176 goto drop;
177
178 hdrlen = sizeof(struct guehdr) + optlen;
179
180 if (fou->family == AF_INET)
181 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len);
182 else
183 ipv6_hdr(skb)->payload_len =
184 htons(ntohs(ipv6_hdr(skb)->payload_len) - len);
185
186 /* Pull csum through the guehdr now . This can be used if
187 * there is a remote checksum offload.
188 */
189 skb_postpull_rcsum(skb, udp_hdr(skb), len);
190
191 data = &guehdr[1];
192
193 if (guehdr->flags & GUE_FLAG_PRIV) {
194 __be32 flags = *(__be32 *)(data + doffset);
195
196 doffset += GUE_LEN_PRIV;
197
198 if (flags & GUE_PFLAG_REMCSUM) {
199 guehdr = gue_remcsum(skb, guehdr, data + doffset,
200 hdrlen, guehdr->proto_ctype,
201 !!(fou->flags &
202 FOU_F_REMCSUM_NOPARTIAL));
203 if (!guehdr)
204 goto drop;
205
206 data = &guehdr[1];
207
208 doffset += GUE_PLEN_REMCSUM;
209 }
210 }
211
212 if (unlikely(guehdr->control))
213 return gue_control_message(skb, guehdr);
214
215 proto_ctype = guehdr->proto_ctype;
216 __skb_pull(skb, sizeof(struct udphdr) + hdrlen);
217 skb_reset_transport_header(skb);
218
219 if (iptunnel_pull_offloads(skb))
220 goto drop;
221
222 return -proto_ctype;
223
224drop:
225 kfree_skb(skb);
226 return 0;
227}
228
229static struct sk_buff *fou_gro_receive(struct sock *sk,
230 struct list_head *head,
231 struct sk_buff *skb)
232{
233 u8 proto = fou_from_sock(sk)->protocol;
234 const struct net_offload **offloads;
235 const struct net_offload *ops;
236 struct sk_buff *pp = NULL;
237
238 /* We can clear the encap_mark for FOU as we are essentially doing
239 * one of two possible things. We are either adding an L4 tunnel
240 * header to the outer L3 tunnel header, or we are simply
241 * treating the GRE tunnel header as though it is a UDP protocol
242 * specific header such as VXLAN or GENEVE.
243 */
244 NAPI_GRO_CB(skb)->encap_mark = 0;
245
246 /* Flag this frame as already having an outer encap header */
247 NAPI_GRO_CB(skb)->is_fou = 1;
248
249 rcu_read_lock();
250 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
251 ops = rcu_dereference(offloads[proto]);
252 if (!ops || !ops->callbacks.gro_receive)
253 goto out_unlock;
254
255 pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
256
257out_unlock:
258 rcu_read_unlock();
259
260 return pp;
261}
262
263static int fou_gro_complete(struct sock *sk, struct sk_buff *skb,
264 int nhoff)
265{
266 const struct net_offload *ops;
267 u8 proto = fou_from_sock(sk)->protocol;
268 int err = -ENOSYS;
269 const struct net_offload **offloads;
270
271 rcu_read_lock();
272 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
273 ops = rcu_dereference(offloads[proto]);
274 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
275 goto out_unlock;
276
277 err = ops->callbacks.gro_complete(skb, nhoff);
278
279 skb_set_inner_mac_header(skb, nhoff);
280
281out_unlock:
282 rcu_read_unlock();
283
284 return err;
285}
286
287static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off,
288 struct guehdr *guehdr, void *data,
289 size_t hdrlen, struct gro_remcsum *grc,
290 bool nopartial)
291{
292 __be16 *pd = data;
293 size_t start = ntohs(pd[0]);
294 size_t offset = ntohs(pd[1]);
295
296 if (skb->remcsum_offload)
297 return guehdr;
298
299 if (!NAPI_GRO_CB(skb)->csum_valid)
300 return NULL;
301
302 guehdr = skb_gro_remcsum_process(skb, (void *)guehdr, off, hdrlen,
303 start, offset, grc, nopartial);
304
305 skb->remcsum_offload = 1;
306
307 return guehdr;
308}
309
310static struct sk_buff *gue_gro_receive(struct sock *sk,
311 struct list_head *head,
312 struct sk_buff *skb)
313{
314 const struct net_offload **offloads;
315 const struct net_offload *ops;
316 struct sk_buff *pp = NULL;
317 struct sk_buff *p;
318 struct guehdr *guehdr;
319 size_t len, optlen, hdrlen, off;
320 void *data;
321 u16 doffset = 0;
322 int flush = 1;
323 struct fou *fou = fou_from_sock(sk);
324 struct gro_remcsum grc;
325 u8 proto;
326
327 skb_gro_remcsum_init(&grc);
328
329 off = skb_gro_offset(skb);
330 len = off + sizeof(*guehdr);
331
332 guehdr = skb_gro_header_fast(skb, off);
333 if (skb_gro_header_hard(skb, len)) {
334 guehdr = skb_gro_header_slow(skb, len, off);
335 if (unlikely(!guehdr))
336 goto out;
337 }
338
339 switch (guehdr->version) {
340 case 0:
341 break;
342 case 1:
343 switch (((struct iphdr *)guehdr)->version) {
344 case 4:
345 proto = IPPROTO_IPIP;
346 break;
347 case 6:
348 proto = IPPROTO_IPV6;
349 break;
350 default:
351 goto out;
352 }
353 goto next_proto;
354 default:
355 goto out;
356 }
357
358 optlen = guehdr->hlen << 2;
359 len += optlen;
360
361 if (skb_gro_header_hard(skb, len)) {
362 guehdr = skb_gro_header_slow(skb, len, off);
363 if (unlikely(!guehdr))
364 goto out;
365 }
366
367 if (unlikely(guehdr->control) || guehdr->version != 0 ||
368 validate_gue_flags(guehdr, optlen))
369 goto out;
370
371 hdrlen = sizeof(*guehdr) + optlen;
372
373 /* Adjust NAPI_GRO_CB(skb)->csum to account for guehdr,
374 * this is needed if there is a remote checkcsum offload.
375 */
376 skb_gro_postpull_rcsum(skb, guehdr, hdrlen);
377
378 data = &guehdr[1];
379
380 if (guehdr->flags & GUE_FLAG_PRIV) {
381 __be32 flags = *(__be32 *)(data + doffset);
382
383 doffset += GUE_LEN_PRIV;
384
385 if (flags & GUE_PFLAG_REMCSUM) {
386 guehdr = gue_gro_remcsum(skb, off, guehdr,
387 data + doffset, hdrlen, &grc,
388 !!(fou->flags &
389 FOU_F_REMCSUM_NOPARTIAL));
390
391 if (!guehdr)
392 goto out;
393
394 data = &guehdr[1];
395
396 doffset += GUE_PLEN_REMCSUM;
397 }
398 }
399
400 skb_gro_pull(skb, hdrlen);
401
402 list_for_each_entry(p, head, list) {
403 const struct guehdr *guehdr2;
404
405 if (!NAPI_GRO_CB(p)->same_flow)
406 continue;
407
408 guehdr2 = (struct guehdr *)(p->data + off);
409
410 /* Compare base GUE header to be equal (covers
411 * hlen, version, proto_ctype, and flags.
412 */
413 if (guehdr->word != guehdr2->word) {
414 NAPI_GRO_CB(p)->same_flow = 0;
415 continue;
416 }
417
418 /* Compare optional fields are the same. */
419 if (guehdr->hlen && memcmp(&guehdr[1], &guehdr2[1],
420 guehdr->hlen << 2)) {
421 NAPI_GRO_CB(p)->same_flow = 0;
422 continue;
423 }
424 }
425
426 proto = guehdr->proto_ctype;
427
428next_proto:
429
430 /* We can clear the encap_mark for GUE as we are essentially doing
431 * one of two possible things. We are either adding an L4 tunnel
432 * header to the outer L3 tunnel header, or we are simply
433 * treating the GRE tunnel header as though it is a UDP protocol
434 * specific header such as VXLAN or GENEVE.
435 */
436 NAPI_GRO_CB(skb)->encap_mark = 0;
437
438 /* Flag this frame as already having an outer encap header */
439 NAPI_GRO_CB(skb)->is_fou = 1;
440
441 rcu_read_lock();
442 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
443 ops = rcu_dereference(offloads[proto]);
444 if (WARN_ON_ONCE(!ops || !ops->callbacks.gro_receive))
445 goto out_unlock;
446
447 pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
448 flush = 0;
449
450out_unlock:
451 rcu_read_unlock();
452out:
453 skb_gro_flush_final_remcsum(skb, pp, flush, &grc);
454
455 return pp;
456}
457
458static int gue_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff)
459{
460 const struct net_offload **offloads;
461 struct guehdr *guehdr = (struct guehdr *)(skb->data + nhoff);
462 const struct net_offload *ops;
463 unsigned int guehlen = 0;
464 u8 proto;
465 int err = -ENOENT;
466
467 switch (guehdr->version) {
468 case 0:
469 proto = guehdr->proto_ctype;
470 guehlen = sizeof(*guehdr) + (guehdr->hlen << 2);
471 break;
472 case 1:
473 switch (((struct iphdr *)guehdr)->version) {
474 case 4:
475 proto = IPPROTO_IPIP;
476 break;
477 case 6:
478 proto = IPPROTO_IPV6;
479 break;
480 default:
481 return err;
482 }
483 break;
484 default:
485 return err;
486 }
487
488 rcu_read_lock();
489 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
490 ops = rcu_dereference(offloads[proto]);
491 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
492 goto out_unlock;
493
494 err = ops->callbacks.gro_complete(skb, nhoff + guehlen);
495
496 skb_set_inner_mac_header(skb, nhoff + guehlen);
497
498out_unlock:
499 rcu_read_unlock();
500 return err;
501}
502
503static bool fou_cfg_cmp(struct fou *fou, struct fou_cfg *cfg)
504{
505 struct sock *sk = fou->sock->sk;
506 struct udp_port_cfg *udp_cfg = &cfg->udp_config;
507
508 if (fou->family != udp_cfg->family ||
509 fou->port != udp_cfg->local_udp_port ||
510 sk->sk_dport != udp_cfg->peer_udp_port ||
511 sk->sk_bound_dev_if != udp_cfg->bind_ifindex)
512 return false;
513
514 if (fou->family == AF_INET) {
515 if (sk->sk_rcv_saddr != udp_cfg->local_ip.s_addr ||
516 sk->sk_daddr != udp_cfg->peer_ip.s_addr)
517 return false;
518 else
519 return true;
520#if IS_ENABLED(CONFIG_IPV6)
521 } else {
522 if (ipv6_addr_cmp(&sk->sk_v6_rcv_saddr, &udp_cfg->local_ip6) ||
523 ipv6_addr_cmp(&sk->sk_v6_daddr, &udp_cfg->peer_ip6))
524 return false;
525 else
526 return true;
527#endif
528 }
529
530 return false;
531}
532
533static int fou_add_to_port_list(struct net *net, struct fou *fou,
534 struct fou_cfg *cfg)
535{
536 struct fou_net *fn = net_generic(net, fou_net_id);
537 struct fou *fout;
538
539 mutex_lock(&fn->fou_lock);
540 list_for_each_entry(fout, &fn->fou_list, list) {
541 if (fou_cfg_cmp(fout, cfg)) {
542 mutex_unlock(&fn->fou_lock);
543 return -EALREADY;
544 }
545 }
546
547 list_add(&fou->list, &fn->fou_list);
548 mutex_unlock(&fn->fou_lock);
549
550 return 0;
551}
552
553static void fou_release(struct fou *fou)
554{
555 struct socket *sock = fou->sock;
556
557 list_del(&fou->list);
558 udp_tunnel_sock_release(sock);
559
560 kfree_rcu(fou, rcu);
561}
562
563static int fou_create(struct net *net, struct fou_cfg *cfg,
564 struct socket **sockp)
565{
566 struct socket *sock = NULL;
567 struct fou *fou = NULL;
568 struct sock *sk;
569 struct udp_tunnel_sock_cfg tunnel_cfg;
570 int err;
571
572 /* Open UDP socket */
573 err = udp_sock_create(net, &cfg->udp_config, &sock);
574 if (err < 0)
575 goto error;
576
577 /* Allocate FOU port structure */
578 fou = kzalloc(sizeof(*fou), GFP_KERNEL);
579 if (!fou) {
580 err = -ENOMEM;
581 goto error;
582 }
583
584 sk = sock->sk;
585
586 fou->port = cfg->udp_config.local_udp_port;
587 fou->family = cfg->udp_config.family;
588 fou->flags = cfg->flags;
589 fou->type = cfg->type;
590 fou->sock = sock;
591
592 memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
593 tunnel_cfg.encap_type = 1;
594 tunnel_cfg.sk_user_data = fou;
595 tunnel_cfg.encap_destroy = NULL;
596
597 /* Initial for fou type */
598 switch (cfg->type) {
599 case FOU_ENCAP_DIRECT:
600 tunnel_cfg.encap_rcv = fou_udp_recv;
601 tunnel_cfg.gro_receive = fou_gro_receive;
602 tunnel_cfg.gro_complete = fou_gro_complete;
603 fou->protocol = cfg->protocol;
604 break;
605 case FOU_ENCAP_GUE:
606 tunnel_cfg.encap_rcv = gue_udp_recv;
607 tunnel_cfg.gro_receive = gue_gro_receive;
608 tunnel_cfg.gro_complete = gue_gro_complete;
609 break;
610 default:
611 err = -EINVAL;
612 goto error;
613 }
614
615 setup_udp_tunnel_sock(net, sock, &tunnel_cfg);
616
617 sk->sk_allocation = GFP_ATOMIC;
618
619 err = fou_add_to_port_list(net, fou, cfg);
620 if (err)
621 goto error;
622
623 if (sockp)
624 *sockp = sock;
625
626 return 0;
627
628error:
629 kfree(fou);
630 if (sock)
631 udp_tunnel_sock_release(sock);
632
633 return err;
634}
635
636static int fou_destroy(struct net *net, struct fou_cfg *cfg)
637{
638 struct fou_net *fn = net_generic(net, fou_net_id);
639 int err = -EINVAL;
640 struct fou *fou;
641
642 mutex_lock(&fn->fou_lock);
643 list_for_each_entry(fou, &fn->fou_list, list) {
644 if (fou_cfg_cmp(fou, cfg)) {
645 fou_release(fou);
646 err = 0;
647 break;
648 }
649 }
650 mutex_unlock(&fn->fou_lock);
651
652 return err;
653}
654
655static struct genl_family fou_nl_family;
656
657static const struct nla_policy fou_nl_policy[FOU_ATTR_MAX + 1] = {
658 [FOU_ATTR_PORT] = { .type = NLA_U16, },
659 [FOU_ATTR_AF] = { .type = NLA_U8, },
660 [FOU_ATTR_IPPROTO] = { .type = NLA_U8, },
661 [FOU_ATTR_TYPE] = { .type = NLA_U8, },
662 [FOU_ATTR_REMCSUM_NOPARTIAL] = { .type = NLA_FLAG, },
663 [FOU_ATTR_LOCAL_V4] = { .type = NLA_U32, },
664 [FOU_ATTR_PEER_V4] = { .type = NLA_U32, },
665 [FOU_ATTR_LOCAL_V6] = { .len = sizeof(struct in6_addr), },
666 [FOU_ATTR_PEER_V6] = { .len = sizeof(struct in6_addr), },
667 [FOU_ATTR_PEER_PORT] = { .type = NLA_U16, },
668 [FOU_ATTR_IFINDEX] = { .type = NLA_S32, },
669};
670
671static int parse_nl_config(struct genl_info *info,
672 struct fou_cfg *cfg)
673{
674 bool has_local = false, has_peer = false;
675 struct nlattr *attr;
676 int ifindex;
677 __be16 port;
678
679 memset(cfg, 0, sizeof(*cfg));
680
681 cfg->udp_config.family = AF_INET;
682
683 if (info->attrs[FOU_ATTR_AF]) {
684 u8 family = nla_get_u8(info->attrs[FOU_ATTR_AF]);
685
686 switch (family) {
687 case AF_INET:
688 break;
689 case AF_INET6:
690 cfg->udp_config.ipv6_v6only = 1;
691 break;
692 default:
693 return -EAFNOSUPPORT;
694 }
695
696 cfg->udp_config.family = family;
697 }
698
699 if (info->attrs[FOU_ATTR_PORT]) {
700 port = nla_get_be16(info->attrs[FOU_ATTR_PORT]);
701 cfg->udp_config.local_udp_port = port;
702 }
703
704 if (info->attrs[FOU_ATTR_IPPROTO])
705 cfg->protocol = nla_get_u8(info->attrs[FOU_ATTR_IPPROTO]);
706
707 if (info->attrs[FOU_ATTR_TYPE])
708 cfg->type = nla_get_u8(info->attrs[FOU_ATTR_TYPE]);
709
710 if (info->attrs[FOU_ATTR_REMCSUM_NOPARTIAL])
711 cfg->flags |= FOU_F_REMCSUM_NOPARTIAL;
712
713 if (cfg->udp_config.family == AF_INET) {
714 if (info->attrs[FOU_ATTR_LOCAL_V4]) {
715 attr = info->attrs[FOU_ATTR_LOCAL_V4];
716 cfg->udp_config.local_ip.s_addr = nla_get_in_addr(attr);
717 has_local = true;
718 }
719
720 if (info->attrs[FOU_ATTR_PEER_V4]) {
721 attr = info->attrs[FOU_ATTR_PEER_V4];
722 cfg->udp_config.peer_ip.s_addr = nla_get_in_addr(attr);
723 has_peer = true;
724 }
725#if IS_ENABLED(CONFIG_IPV6)
726 } else {
727 if (info->attrs[FOU_ATTR_LOCAL_V6]) {
728 attr = info->attrs[FOU_ATTR_LOCAL_V6];
729 cfg->udp_config.local_ip6 = nla_get_in6_addr(attr);
730 has_local = true;
731 }
732
733 if (info->attrs[FOU_ATTR_PEER_V6]) {
734 attr = info->attrs[FOU_ATTR_PEER_V6];
735 cfg->udp_config.peer_ip6 = nla_get_in6_addr(attr);
736 has_peer = true;
737 }
738#endif
739 }
740
741 if (has_peer) {
742 if (info->attrs[FOU_ATTR_PEER_PORT]) {
743 port = nla_get_be16(info->attrs[FOU_ATTR_PEER_PORT]);
744 cfg->udp_config.peer_udp_port = port;
745 } else {
746 return -EINVAL;
747 }
748 }
749
750 if (info->attrs[FOU_ATTR_IFINDEX]) {
751 if (!has_local)
752 return -EINVAL;
753
754 ifindex = nla_get_s32(info->attrs[FOU_ATTR_IFINDEX]);
755
756 cfg->udp_config.bind_ifindex = ifindex;
757 }
758
759 return 0;
760}
761
762static int fou_nl_cmd_add_port(struct sk_buff *skb, struct genl_info *info)
763{
764 struct net *net = genl_info_net(info);
765 struct fou_cfg cfg;
766 int err;
767
768 err = parse_nl_config(info, &cfg);
769 if (err)
770 return err;
771
772 return fou_create(net, &cfg, NULL);
773}
774
775static int fou_nl_cmd_rm_port(struct sk_buff *skb, struct genl_info *info)
776{
777 struct net *net = genl_info_net(info);
778 struct fou_cfg cfg;
779 int err;
780
781 err = parse_nl_config(info, &cfg);
782 if (err)
783 return err;
784
785 return fou_destroy(net, &cfg);
786}
787
788static int fou_fill_info(struct fou *fou, struct sk_buff *msg)
789{
790 struct sock *sk = fou->sock->sk;
791
792 if (nla_put_u8(msg, FOU_ATTR_AF, fou->sock->sk->sk_family) ||
793 nla_put_be16(msg, FOU_ATTR_PORT, fou->port) ||
794 nla_put_be16(msg, FOU_ATTR_PEER_PORT, sk->sk_dport) ||
795 nla_put_u8(msg, FOU_ATTR_IPPROTO, fou->protocol) ||
796 nla_put_u8(msg, FOU_ATTR_TYPE, fou->type) ||
797 nla_put_s32(msg, FOU_ATTR_IFINDEX, sk->sk_bound_dev_if))
798 return -1;
799
800 if (fou->flags & FOU_F_REMCSUM_NOPARTIAL)
801 if (nla_put_flag(msg, FOU_ATTR_REMCSUM_NOPARTIAL))
802 return -1;
803
804 if (fou->sock->sk->sk_family == AF_INET) {
805 if (nla_put_in_addr(msg, FOU_ATTR_LOCAL_V4, sk->sk_rcv_saddr))
806 return -1;
807
808 if (nla_put_in_addr(msg, FOU_ATTR_PEER_V4, sk->sk_daddr))
809 return -1;
810#if IS_ENABLED(CONFIG_IPV6)
811 } else {
812 if (nla_put_in6_addr(msg, FOU_ATTR_LOCAL_V6,
813 &sk->sk_v6_rcv_saddr))
814 return -1;
815
816 if (nla_put_in6_addr(msg, FOU_ATTR_PEER_V6, &sk->sk_v6_daddr))
817 return -1;
818#endif
819 }
820
821 return 0;
822}
823
824static int fou_dump_info(struct fou *fou, u32 portid, u32 seq,
825 u32 flags, struct sk_buff *skb, u8 cmd)
826{
827 void *hdr;
828
829 hdr = genlmsg_put(skb, portid, seq, &fou_nl_family, flags, cmd);
830 if (!hdr)
831 return -ENOMEM;
832
833 if (fou_fill_info(fou, skb) < 0)
834 goto nla_put_failure;
835
836 genlmsg_end(skb, hdr);
837 return 0;
838
839nla_put_failure:
840 genlmsg_cancel(skb, hdr);
841 return -EMSGSIZE;
842}
843
844static int fou_nl_cmd_get_port(struct sk_buff *skb, struct genl_info *info)
845{
846 struct net *net = genl_info_net(info);
847 struct fou_net *fn = net_generic(net, fou_net_id);
848 struct sk_buff *msg;
849 struct fou_cfg cfg;
850 struct fou *fout;
851 __be16 port;
852 u8 family;
853 int ret;
854
855 ret = parse_nl_config(info, &cfg);
856 if (ret)
857 return ret;
858 port = cfg.udp_config.local_udp_port;
859 if (port == 0)
860 return -EINVAL;
861
862 family = cfg.udp_config.family;
863 if (family != AF_INET && family != AF_INET6)
864 return -EINVAL;
865
866 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
867 if (!msg)
868 return -ENOMEM;
869
870 ret = -ESRCH;
871 mutex_lock(&fn->fou_lock);
872 list_for_each_entry(fout, &fn->fou_list, list) {
873 if (fou_cfg_cmp(fout, &cfg)) {
874 ret = fou_dump_info(fout, info->snd_portid,
875 info->snd_seq, 0, msg,
876 info->genlhdr->cmd);
877 break;
878 }
879 }
880 mutex_unlock(&fn->fou_lock);
881 if (ret < 0)
882 goto out_free;
883
884 return genlmsg_reply(msg, info);
885
886out_free:
887 nlmsg_free(msg);
888 return ret;
889}
890
891static int fou_nl_dump(struct sk_buff *skb, struct netlink_callback *cb)
892{
893 struct net *net = sock_net(skb->sk);
894 struct fou_net *fn = net_generic(net, fou_net_id);
895 struct fou *fout;
896 int idx = 0, ret;
897
898 mutex_lock(&fn->fou_lock);
899 list_for_each_entry(fout, &fn->fou_list, list) {
900 if (idx++ < cb->args[0])
901 continue;
902 ret = fou_dump_info(fout, NETLINK_CB(cb->skb).portid,
903 cb->nlh->nlmsg_seq, NLM_F_MULTI,
904 skb, FOU_CMD_GET);
905 if (ret)
906 break;
907 }
908 mutex_unlock(&fn->fou_lock);
909
910 cb->args[0] = idx;
911 return skb->len;
912}
913
914static const struct genl_small_ops fou_nl_ops[] = {
915 {
916 .cmd = FOU_CMD_ADD,
917 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
918 .doit = fou_nl_cmd_add_port,
919 .flags = GENL_ADMIN_PERM,
920 },
921 {
922 .cmd = FOU_CMD_DEL,
923 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
924 .doit = fou_nl_cmd_rm_port,
925 .flags = GENL_ADMIN_PERM,
926 },
927 {
928 .cmd = FOU_CMD_GET,
929 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
930 .doit = fou_nl_cmd_get_port,
931 .dumpit = fou_nl_dump,
932 },
933};
934
935static struct genl_family fou_nl_family __ro_after_init = {
936 .hdrsize = 0,
937 .name = FOU_GENL_NAME,
938 .version = FOU_GENL_VERSION,
939 .maxattr = FOU_ATTR_MAX,
940 .policy = fou_nl_policy,
941 .netnsok = true,
942 .module = THIS_MODULE,
943 .small_ops = fou_nl_ops,
944 .n_small_ops = ARRAY_SIZE(fou_nl_ops),
945};
946
947size_t fou_encap_hlen(struct ip_tunnel_encap *e)
948{
949 return sizeof(struct udphdr);
950}
951EXPORT_SYMBOL(fou_encap_hlen);
952
953size_t gue_encap_hlen(struct ip_tunnel_encap *e)
954{
955 size_t len;
956 bool need_priv = false;
957
958 len = sizeof(struct udphdr) + sizeof(struct guehdr);
959
960 if (e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) {
961 len += GUE_PLEN_REMCSUM;
962 need_priv = true;
963 }
964
965 len += need_priv ? GUE_LEN_PRIV : 0;
966
967 return len;
968}
969EXPORT_SYMBOL(gue_encap_hlen);
970
971int __fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
972 u8 *protocol, __be16 *sport, int type)
973{
974 int err;
975
976 err = iptunnel_handle_offloads(skb, type);
977 if (err)
978 return err;
979
980 *sport = e->sport ? : udp_flow_src_port(dev_net(skb->dev),
981 skb, 0, 0, false);
982
983 return 0;
984}
985EXPORT_SYMBOL(__fou_build_header);
986
987int __gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
988 u8 *protocol, __be16 *sport, int type)
989{
990 struct guehdr *guehdr;
991 size_t hdrlen, optlen = 0;
992 void *data;
993 bool need_priv = false;
994 int err;
995
996 if ((e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) &&
997 skb->ip_summed == CHECKSUM_PARTIAL) {
998 optlen += GUE_PLEN_REMCSUM;
999 type |= SKB_GSO_TUNNEL_REMCSUM;
1000 need_priv = true;
1001 }
1002
1003 optlen += need_priv ? GUE_LEN_PRIV : 0;
1004
1005 err = iptunnel_handle_offloads(skb, type);
1006 if (err)
1007 return err;
1008
1009 /* Get source port (based on flow hash) before skb_push */
1010 *sport = e->sport ? : udp_flow_src_port(dev_net(skb->dev),
1011 skb, 0, 0, false);
1012
1013 hdrlen = sizeof(struct guehdr) + optlen;
1014
1015 skb_push(skb, hdrlen);
1016
1017 guehdr = (struct guehdr *)skb->data;
1018
1019 guehdr->control = 0;
1020 guehdr->version = 0;
1021 guehdr->hlen = optlen >> 2;
1022 guehdr->flags = 0;
1023 guehdr->proto_ctype = *protocol;
1024
1025 data = &guehdr[1];
1026
1027 if (need_priv) {
1028 __be32 *flags = data;
1029
1030 guehdr->flags |= GUE_FLAG_PRIV;
1031 *flags = 0;
1032 data += GUE_LEN_PRIV;
1033
1034 if (type & SKB_GSO_TUNNEL_REMCSUM) {
1035 u16 csum_start = skb_checksum_start_offset(skb);
1036 __be16 *pd = data;
1037
1038 if (csum_start < hdrlen)
1039 return -EINVAL;
1040
1041 csum_start -= hdrlen;
1042 pd[0] = htons(csum_start);
1043 pd[1] = htons(csum_start + skb->csum_offset);
1044
1045 if (!skb_is_gso(skb)) {
1046 skb->ip_summed = CHECKSUM_NONE;
1047 skb->encapsulation = 0;
1048 }
1049
1050 *flags |= GUE_PFLAG_REMCSUM;
1051 data += GUE_PLEN_REMCSUM;
1052 }
1053
1054 }
1055
1056 return 0;
1057}
1058EXPORT_SYMBOL(__gue_build_header);
1059
1060#ifdef CONFIG_NET_FOU_IP_TUNNELS
1061
1062static void fou_build_udp(struct sk_buff *skb, struct ip_tunnel_encap *e,
1063 struct flowi4 *fl4, u8 *protocol, __be16 sport)
1064{
1065 struct udphdr *uh;
1066
1067 skb_push(skb, sizeof(struct udphdr));
1068 skb_reset_transport_header(skb);
1069
1070 uh = udp_hdr(skb);
1071
1072 uh->dest = e->dport;
1073 uh->source = sport;
1074 uh->len = htons(skb->len);
1075 udp_set_csum(!(e->flags & TUNNEL_ENCAP_FLAG_CSUM), skb,
1076 fl4->saddr, fl4->daddr, skb->len);
1077
1078 *protocol = IPPROTO_UDP;
1079}
1080
1081static int fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
1082 u8 *protocol, struct flowi4 *fl4)
1083{
1084 int type = e->flags & TUNNEL_ENCAP_FLAG_CSUM ? SKB_GSO_UDP_TUNNEL_CSUM :
1085 SKB_GSO_UDP_TUNNEL;
1086 __be16 sport;
1087 int err;
1088
1089 err = __fou_build_header(skb, e, protocol, &sport, type);
1090 if (err)
1091 return err;
1092
1093 fou_build_udp(skb, e, fl4, protocol, sport);
1094
1095 return 0;
1096}
1097
1098static int gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
1099 u8 *protocol, struct flowi4 *fl4)
1100{
1101 int type = e->flags & TUNNEL_ENCAP_FLAG_CSUM ? SKB_GSO_UDP_TUNNEL_CSUM :
1102 SKB_GSO_UDP_TUNNEL;
1103 __be16 sport;
1104 int err;
1105
1106 err = __gue_build_header(skb, e, protocol, &sport, type);
1107 if (err)
1108 return err;
1109
1110 fou_build_udp(skb, e, fl4, protocol, sport);
1111
1112 return 0;
1113}
1114
1115static int gue_err_proto_handler(int proto, struct sk_buff *skb, u32 info)
1116{
1117 const struct net_protocol *ipprot = rcu_dereference(inet_protos[proto]);
1118
1119 if (ipprot && ipprot->err_handler) {
1120 if (!ipprot->err_handler(skb, info))
1121 return 0;
1122 }
1123
1124 return -ENOENT;
1125}
1126
1127static int gue_err(struct sk_buff *skb, u32 info)
1128{
1129 int transport_offset = skb_transport_offset(skb);
1130 struct guehdr *guehdr;
1131 size_t len, optlen;
1132 int ret;
1133
1134 len = sizeof(struct udphdr) + sizeof(struct guehdr);
1135 if (!pskb_may_pull(skb, transport_offset + len))
1136 return -EINVAL;
1137
1138 guehdr = (struct guehdr *)&udp_hdr(skb)[1];
1139
1140 switch (guehdr->version) {
1141 case 0: /* Full GUE header present */
1142 break;
1143 case 1: {
1144 /* Direct encapsulation of IPv4 or IPv6 */
1145 skb_set_transport_header(skb, -(int)sizeof(struct icmphdr));
1146
1147 switch (((struct iphdr *)guehdr)->version) {
1148 case 4:
1149 ret = gue_err_proto_handler(IPPROTO_IPIP, skb, info);
1150 goto out;
1151#if IS_ENABLED(CONFIG_IPV6)
1152 case 6:
1153 ret = gue_err_proto_handler(IPPROTO_IPV6, skb, info);
1154 goto out;
1155#endif
1156 default:
1157 ret = -EOPNOTSUPP;
1158 goto out;
1159 }
1160 }
1161 default: /* Undefined version */
1162 return -EOPNOTSUPP;
1163 }
1164
1165 if (guehdr->control)
1166 return -ENOENT;
1167
1168 optlen = guehdr->hlen << 2;
1169
1170 if (!pskb_may_pull(skb, transport_offset + len + optlen))
1171 return -EINVAL;
1172
1173 guehdr = (struct guehdr *)&udp_hdr(skb)[1];
1174 if (validate_gue_flags(guehdr, optlen))
1175 return -EINVAL;
1176
1177 /* Handling exceptions for direct UDP encapsulation in GUE would lead to
1178 * recursion. Besides, this kind of encapsulation can't even be
1179 * configured currently. Discard this.
1180 */
1181 if (guehdr->proto_ctype == IPPROTO_UDP ||
1182 guehdr->proto_ctype == IPPROTO_UDPLITE)
1183 return -EOPNOTSUPP;
1184
1185 skb_set_transport_header(skb, -(int)sizeof(struct icmphdr));
1186 ret = gue_err_proto_handler(guehdr->proto_ctype, skb, info);
1187
1188out:
1189 skb_set_transport_header(skb, transport_offset);
1190 return ret;
1191}
1192
1193
1194static const struct ip_tunnel_encap_ops fou_iptun_ops = {
1195 .encap_hlen = fou_encap_hlen,
1196 .build_header = fou_build_header,
1197 .err_handler = gue_err,
1198};
1199
1200static const struct ip_tunnel_encap_ops gue_iptun_ops = {
1201 .encap_hlen = gue_encap_hlen,
1202 .build_header = gue_build_header,
1203 .err_handler = gue_err,
1204};
1205
1206static int ip_tunnel_encap_add_fou_ops(void)
1207{
1208 int ret;
1209
1210 ret = ip_tunnel_encap_add_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
1211 if (ret < 0) {
1212 pr_err("can't add fou ops\n");
1213 return ret;
1214 }
1215
1216 ret = ip_tunnel_encap_add_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE);
1217 if (ret < 0) {
1218 pr_err("can't add gue ops\n");
1219 ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
1220 return ret;
1221 }
1222
1223 return 0;
1224}
1225
1226static void ip_tunnel_encap_del_fou_ops(void)
1227{
1228 ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
1229 ip_tunnel_encap_del_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE);
1230}
1231
1232#else
1233
1234static int ip_tunnel_encap_add_fou_ops(void)
1235{
1236 return 0;
1237}
1238
1239static void ip_tunnel_encap_del_fou_ops(void)
1240{
1241}
1242
1243#endif
1244
1245static __net_init int fou_init_net(struct net *net)
1246{
1247 struct fou_net *fn = net_generic(net, fou_net_id);
1248
1249 INIT_LIST_HEAD(&fn->fou_list);
1250 mutex_init(&fn->fou_lock);
1251 return 0;
1252}
1253
1254static __net_exit void fou_exit_net(struct net *net)
1255{
1256 struct fou_net *fn = net_generic(net, fou_net_id);
1257 struct fou *fou, *next;
1258
1259 /* Close all the FOU sockets */
1260 mutex_lock(&fn->fou_lock);
1261 list_for_each_entry_safe(fou, next, &fn->fou_list, list)
1262 fou_release(fou);
1263 mutex_unlock(&fn->fou_lock);
1264}
1265
1266static struct pernet_operations fou_net_ops = {
1267 .init = fou_init_net,
1268 .exit = fou_exit_net,
1269 .id = &fou_net_id,
1270 .size = sizeof(struct fou_net),
1271};
1272
1273static int __init fou_init(void)
1274{
1275 int ret;
1276
1277 ret = register_pernet_device(&fou_net_ops);
1278 if (ret)
1279 goto exit;
1280
1281 ret = genl_register_family(&fou_nl_family);
1282 if (ret < 0)
1283 goto unregister;
1284
1285 ret = ip_tunnel_encap_add_fou_ops();
1286 if (ret == 0)
1287 return 0;
1288
1289 genl_unregister_family(&fou_nl_family);
1290unregister:
1291 unregister_pernet_device(&fou_net_ops);
1292exit:
1293 return ret;
1294}
1295
1296static void __exit fou_fini(void)
1297{
1298 ip_tunnel_encap_del_fou_ops();
1299 genl_unregister_family(&fou_nl_family);
1300 unregister_pernet_device(&fou_net_ops);
1301}
1302
1303module_init(fou_init);
1304module_exit(fou_fini);
1305MODULE_AUTHOR("Tom Herbert <therbert@google.com>");
1306MODULE_LICENSE("GPL");
1307MODULE_DESCRIPTION("Foo over UDP");
1#include <linux/module.h>
2#include <linux/errno.h>
3#include <linux/socket.h>
4#include <linux/skbuff.h>
5#include <linux/ip.h>
6#include <linux/udp.h>
7#include <linux/types.h>
8#include <linux/kernel.h>
9#include <net/genetlink.h>
10#include <net/gue.h>
11#include <net/ip.h>
12#include <net/protocol.h>
13#include <net/udp.h>
14#include <net/udp_tunnel.h>
15#include <net/xfrm.h>
16#include <uapi/linux/fou.h>
17#include <uapi/linux/genetlink.h>
18
19struct fou {
20 struct socket *sock;
21 u8 protocol;
22 u8 flags;
23 __be16 port;
24 u8 family;
25 u16 type;
26 struct list_head list;
27 struct rcu_head rcu;
28};
29
30#define FOU_F_REMCSUM_NOPARTIAL BIT(0)
31
32struct fou_cfg {
33 u16 type;
34 u8 protocol;
35 u8 flags;
36 struct udp_port_cfg udp_config;
37};
38
39static unsigned int fou_net_id;
40
41struct fou_net {
42 struct list_head fou_list;
43 struct mutex fou_lock;
44};
45
46static inline struct fou *fou_from_sock(struct sock *sk)
47{
48 return sk->sk_user_data;
49}
50
51static int fou_recv_pull(struct sk_buff *skb, struct fou *fou, size_t len)
52{
53 /* Remove 'len' bytes from the packet (UDP header and
54 * FOU header if present).
55 */
56 if (fou->family == AF_INET)
57 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len);
58 else
59 ipv6_hdr(skb)->payload_len =
60 htons(ntohs(ipv6_hdr(skb)->payload_len) - len);
61
62 __skb_pull(skb, len);
63 skb_postpull_rcsum(skb, udp_hdr(skb), len);
64 skb_reset_transport_header(skb);
65 return iptunnel_pull_offloads(skb);
66}
67
68static int fou_udp_recv(struct sock *sk, struct sk_buff *skb)
69{
70 struct fou *fou = fou_from_sock(sk);
71
72 if (!fou)
73 return 1;
74
75 if (fou_recv_pull(skb, fou, sizeof(struct udphdr)))
76 goto drop;
77
78 return -fou->protocol;
79
80drop:
81 kfree_skb(skb);
82 return 0;
83}
84
85static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr,
86 void *data, size_t hdrlen, u8 ipproto,
87 bool nopartial)
88{
89 __be16 *pd = data;
90 size_t start = ntohs(pd[0]);
91 size_t offset = ntohs(pd[1]);
92 size_t plen = sizeof(struct udphdr) + hdrlen +
93 max_t(size_t, offset + sizeof(u16), start);
94
95 if (skb->remcsum_offload)
96 return guehdr;
97
98 if (!pskb_may_pull(skb, plen))
99 return NULL;
100 guehdr = (struct guehdr *)&udp_hdr(skb)[1];
101
102 skb_remcsum_process(skb, (void *)guehdr + hdrlen,
103 start, offset, nopartial);
104
105 return guehdr;
106}
107
108static int gue_control_message(struct sk_buff *skb, struct guehdr *guehdr)
109{
110 /* No support yet */
111 kfree_skb(skb);
112 return 0;
113}
114
115static int gue_udp_recv(struct sock *sk, struct sk_buff *skb)
116{
117 struct fou *fou = fou_from_sock(sk);
118 size_t len, optlen, hdrlen;
119 struct guehdr *guehdr;
120 void *data;
121 u16 doffset = 0;
122
123 if (!fou)
124 return 1;
125
126 len = sizeof(struct udphdr) + sizeof(struct guehdr);
127 if (!pskb_may_pull(skb, len))
128 goto drop;
129
130 guehdr = (struct guehdr *)&udp_hdr(skb)[1];
131
132 switch (guehdr->version) {
133 case 0: /* Full GUE header present */
134 break;
135
136 case 1: {
137 /* Direct encasulation of IPv4 or IPv6 */
138
139 int prot;
140
141 switch (((struct iphdr *)guehdr)->version) {
142 case 4:
143 prot = IPPROTO_IPIP;
144 break;
145 case 6:
146 prot = IPPROTO_IPV6;
147 break;
148 default:
149 goto drop;
150 }
151
152 if (fou_recv_pull(skb, fou, sizeof(struct udphdr)))
153 goto drop;
154
155 return -prot;
156 }
157
158 default: /* Undefined version */
159 goto drop;
160 }
161
162 optlen = guehdr->hlen << 2;
163 len += optlen;
164
165 if (!pskb_may_pull(skb, len))
166 goto drop;
167
168 /* guehdr may change after pull */
169 guehdr = (struct guehdr *)&udp_hdr(skb)[1];
170
171 hdrlen = sizeof(struct guehdr) + optlen;
172
173 if (guehdr->version != 0 || validate_gue_flags(guehdr, optlen))
174 goto drop;
175
176 hdrlen = sizeof(struct guehdr) + optlen;
177
178 if (fou->family == AF_INET)
179 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len);
180 else
181 ipv6_hdr(skb)->payload_len =
182 htons(ntohs(ipv6_hdr(skb)->payload_len) - len);
183
184 /* Pull csum through the guehdr now . This can be used if
185 * there is a remote checksum offload.
186 */
187 skb_postpull_rcsum(skb, udp_hdr(skb), len);
188
189 data = &guehdr[1];
190
191 if (guehdr->flags & GUE_FLAG_PRIV) {
192 __be32 flags = *(__be32 *)(data + doffset);
193
194 doffset += GUE_LEN_PRIV;
195
196 if (flags & GUE_PFLAG_REMCSUM) {
197 guehdr = gue_remcsum(skb, guehdr, data + doffset,
198 hdrlen, guehdr->proto_ctype,
199 !!(fou->flags &
200 FOU_F_REMCSUM_NOPARTIAL));
201 if (!guehdr)
202 goto drop;
203
204 data = &guehdr[1];
205
206 doffset += GUE_PLEN_REMCSUM;
207 }
208 }
209
210 if (unlikely(guehdr->control))
211 return gue_control_message(skb, guehdr);
212
213 __skb_pull(skb, sizeof(struct udphdr) + hdrlen);
214 skb_reset_transport_header(skb);
215
216 if (iptunnel_pull_offloads(skb))
217 goto drop;
218
219 return -guehdr->proto_ctype;
220
221drop:
222 kfree_skb(skb);
223 return 0;
224}
225
226static struct sk_buff **fou_gro_receive(struct sock *sk,
227 struct sk_buff **head,
228 struct sk_buff *skb)
229{
230 const struct net_offload *ops;
231 struct sk_buff **pp = NULL;
232 u8 proto = fou_from_sock(sk)->protocol;
233 const struct net_offload **offloads;
234
235 /* We can clear the encap_mark for FOU as we are essentially doing
236 * one of two possible things. We are either adding an L4 tunnel
237 * header to the outer L3 tunnel header, or we are are simply
238 * treating the GRE tunnel header as though it is a UDP protocol
239 * specific header such as VXLAN or GENEVE.
240 */
241 NAPI_GRO_CB(skb)->encap_mark = 0;
242
243 /* Flag this frame as already having an outer encap header */
244 NAPI_GRO_CB(skb)->is_fou = 1;
245
246 rcu_read_lock();
247 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
248 ops = rcu_dereference(offloads[proto]);
249 if (!ops || !ops->callbacks.gro_receive)
250 goto out_unlock;
251
252 pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
253
254out_unlock:
255 rcu_read_unlock();
256
257 return pp;
258}
259
260static int fou_gro_complete(struct sock *sk, struct sk_buff *skb,
261 int nhoff)
262{
263 const struct net_offload *ops;
264 u8 proto = fou_from_sock(sk)->protocol;
265 int err = -ENOSYS;
266 const struct net_offload **offloads;
267
268 rcu_read_lock();
269 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
270 ops = rcu_dereference(offloads[proto]);
271 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
272 goto out_unlock;
273
274 err = ops->callbacks.gro_complete(skb, nhoff);
275
276 skb_set_inner_mac_header(skb, nhoff);
277
278out_unlock:
279 rcu_read_unlock();
280
281 return err;
282}
283
284static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off,
285 struct guehdr *guehdr, void *data,
286 size_t hdrlen, struct gro_remcsum *grc,
287 bool nopartial)
288{
289 __be16 *pd = data;
290 size_t start = ntohs(pd[0]);
291 size_t offset = ntohs(pd[1]);
292
293 if (skb->remcsum_offload)
294 return guehdr;
295
296 if (!NAPI_GRO_CB(skb)->csum_valid)
297 return NULL;
298
299 guehdr = skb_gro_remcsum_process(skb, (void *)guehdr, off, hdrlen,
300 start, offset, grc, nopartial);
301
302 skb->remcsum_offload = 1;
303
304 return guehdr;
305}
306
307static struct sk_buff **gue_gro_receive(struct sock *sk,
308 struct sk_buff **head,
309 struct sk_buff *skb)
310{
311 const struct net_offload **offloads;
312 const struct net_offload *ops;
313 struct sk_buff **pp = NULL;
314 struct sk_buff *p;
315 struct guehdr *guehdr;
316 size_t len, optlen, hdrlen, off;
317 void *data;
318 u16 doffset = 0;
319 int flush = 1;
320 struct fou *fou = fou_from_sock(sk);
321 struct gro_remcsum grc;
322 u8 proto;
323
324 skb_gro_remcsum_init(&grc);
325
326 off = skb_gro_offset(skb);
327 len = off + sizeof(*guehdr);
328
329 guehdr = skb_gro_header_fast(skb, off);
330 if (skb_gro_header_hard(skb, len)) {
331 guehdr = skb_gro_header_slow(skb, len, off);
332 if (unlikely(!guehdr))
333 goto out;
334 }
335
336 switch (guehdr->version) {
337 case 0:
338 break;
339 case 1:
340 switch (((struct iphdr *)guehdr)->version) {
341 case 4:
342 proto = IPPROTO_IPIP;
343 break;
344 case 6:
345 proto = IPPROTO_IPV6;
346 break;
347 default:
348 goto out;
349 }
350 goto next_proto;
351 default:
352 goto out;
353 }
354
355 optlen = guehdr->hlen << 2;
356 len += optlen;
357
358 if (skb_gro_header_hard(skb, len)) {
359 guehdr = skb_gro_header_slow(skb, len, off);
360 if (unlikely(!guehdr))
361 goto out;
362 }
363
364 if (unlikely(guehdr->control) || guehdr->version != 0 ||
365 validate_gue_flags(guehdr, optlen))
366 goto out;
367
368 hdrlen = sizeof(*guehdr) + optlen;
369
370 /* Adjust NAPI_GRO_CB(skb)->csum to account for guehdr,
371 * this is needed if there is a remote checkcsum offload.
372 */
373 skb_gro_postpull_rcsum(skb, guehdr, hdrlen);
374
375 data = &guehdr[1];
376
377 if (guehdr->flags & GUE_FLAG_PRIV) {
378 __be32 flags = *(__be32 *)(data + doffset);
379
380 doffset += GUE_LEN_PRIV;
381
382 if (flags & GUE_PFLAG_REMCSUM) {
383 guehdr = gue_gro_remcsum(skb, off, guehdr,
384 data + doffset, hdrlen, &grc,
385 !!(fou->flags &
386 FOU_F_REMCSUM_NOPARTIAL));
387
388 if (!guehdr)
389 goto out;
390
391 data = &guehdr[1];
392
393 doffset += GUE_PLEN_REMCSUM;
394 }
395 }
396
397 skb_gro_pull(skb, hdrlen);
398
399 for (p = *head; p; p = p->next) {
400 const struct guehdr *guehdr2;
401
402 if (!NAPI_GRO_CB(p)->same_flow)
403 continue;
404
405 guehdr2 = (struct guehdr *)(p->data + off);
406
407 /* Compare base GUE header to be equal (covers
408 * hlen, version, proto_ctype, and flags.
409 */
410 if (guehdr->word != guehdr2->word) {
411 NAPI_GRO_CB(p)->same_flow = 0;
412 continue;
413 }
414
415 /* Compare optional fields are the same. */
416 if (guehdr->hlen && memcmp(&guehdr[1], &guehdr2[1],
417 guehdr->hlen << 2)) {
418 NAPI_GRO_CB(p)->same_flow = 0;
419 continue;
420 }
421 }
422
423 proto = guehdr->proto_ctype;
424
425next_proto:
426
427 /* We can clear the encap_mark for GUE as we are essentially doing
428 * one of two possible things. We are either adding an L4 tunnel
429 * header to the outer L3 tunnel header, or we are are simply
430 * treating the GRE tunnel header as though it is a UDP protocol
431 * specific header such as VXLAN or GENEVE.
432 */
433 NAPI_GRO_CB(skb)->encap_mark = 0;
434
435 /* Flag this frame as already having an outer encap header */
436 NAPI_GRO_CB(skb)->is_fou = 1;
437
438 rcu_read_lock();
439 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
440 ops = rcu_dereference(offloads[proto]);
441 if (WARN_ON_ONCE(!ops || !ops->callbacks.gro_receive))
442 goto out_unlock;
443
444 pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
445 flush = 0;
446
447out_unlock:
448 rcu_read_unlock();
449out:
450 NAPI_GRO_CB(skb)->flush |= flush;
451 skb_gro_remcsum_cleanup(skb, &grc);
452
453 return pp;
454}
455
456static int gue_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff)
457{
458 const struct net_offload **offloads;
459 struct guehdr *guehdr = (struct guehdr *)(skb->data + nhoff);
460 const struct net_offload *ops;
461 unsigned int guehlen = 0;
462 u8 proto;
463 int err = -ENOENT;
464
465 switch (guehdr->version) {
466 case 0:
467 proto = guehdr->proto_ctype;
468 guehlen = sizeof(*guehdr) + (guehdr->hlen << 2);
469 break;
470 case 1:
471 switch (((struct iphdr *)guehdr)->version) {
472 case 4:
473 proto = IPPROTO_IPIP;
474 break;
475 case 6:
476 proto = IPPROTO_IPV6;
477 break;
478 default:
479 return err;
480 }
481 break;
482 default:
483 return err;
484 }
485
486 rcu_read_lock();
487 offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
488 ops = rcu_dereference(offloads[proto]);
489 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
490 goto out_unlock;
491
492 err = ops->callbacks.gro_complete(skb, nhoff + guehlen);
493
494 skb_set_inner_mac_header(skb, nhoff + guehlen);
495
496out_unlock:
497 rcu_read_unlock();
498 return err;
499}
500
501static int fou_add_to_port_list(struct net *net, struct fou *fou)
502{
503 struct fou_net *fn = net_generic(net, fou_net_id);
504 struct fou *fout;
505
506 mutex_lock(&fn->fou_lock);
507 list_for_each_entry(fout, &fn->fou_list, list) {
508 if (fou->port == fout->port &&
509 fou->family == fout->family) {
510 mutex_unlock(&fn->fou_lock);
511 return -EALREADY;
512 }
513 }
514
515 list_add(&fou->list, &fn->fou_list);
516 mutex_unlock(&fn->fou_lock);
517
518 return 0;
519}
520
521static void fou_release(struct fou *fou)
522{
523 struct socket *sock = fou->sock;
524
525 list_del(&fou->list);
526 udp_tunnel_sock_release(sock);
527
528 kfree_rcu(fou, rcu);
529}
530
531static int fou_create(struct net *net, struct fou_cfg *cfg,
532 struct socket **sockp)
533{
534 struct socket *sock = NULL;
535 struct fou *fou = NULL;
536 struct sock *sk;
537 struct udp_tunnel_sock_cfg tunnel_cfg;
538 int err;
539
540 /* Open UDP socket */
541 err = udp_sock_create(net, &cfg->udp_config, &sock);
542 if (err < 0)
543 goto error;
544
545 /* Allocate FOU port structure */
546 fou = kzalloc(sizeof(*fou), GFP_KERNEL);
547 if (!fou) {
548 err = -ENOMEM;
549 goto error;
550 }
551
552 sk = sock->sk;
553
554 fou->port = cfg->udp_config.local_udp_port;
555 fou->family = cfg->udp_config.family;
556 fou->flags = cfg->flags;
557 fou->type = cfg->type;
558 fou->sock = sock;
559
560 memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
561 tunnel_cfg.encap_type = 1;
562 tunnel_cfg.sk_user_data = fou;
563 tunnel_cfg.encap_destroy = NULL;
564
565 /* Initial for fou type */
566 switch (cfg->type) {
567 case FOU_ENCAP_DIRECT:
568 tunnel_cfg.encap_rcv = fou_udp_recv;
569 tunnel_cfg.gro_receive = fou_gro_receive;
570 tunnel_cfg.gro_complete = fou_gro_complete;
571 fou->protocol = cfg->protocol;
572 break;
573 case FOU_ENCAP_GUE:
574 tunnel_cfg.encap_rcv = gue_udp_recv;
575 tunnel_cfg.gro_receive = gue_gro_receive;
576 tunnel_cfg.gro_complete = gue_gro_complete;
577 break;
578 default:
579 err = -EINVAL;
580 goto error;
581 }
582
583 setup_udp_tunnel_sock(net, sock, &tunnel_cfg);
584
585 sk->sk_allocation = GFP_ATOMIC;
586
587 err = fou_add_to_port_list(net, fou);
588 if (err)
589 goto error;
590
591 if (sockp)
592 *sockp = sock;
593
594 return 0;
595
596error:
597 kfree(fou);
598 if (sock)
599 udp_tunnel_sock_release(sock);
600
601 return err;
602}
603
604static int fou_destroy(struct net *net, struct fou_cfg *cfg)
605{
606 struct fou_net *fn = net_generic(net, fou_net_id);
607 __be16 port = cfg->udp_config.local_udp_port;
608 u8 family = cfg->udp_config.family;
609 int err = -EINVAL;
610 struct fou *fou;
611
612 mutex_lock(&fn->fou_lock);
613 list_for_each_entry(fou, &fn->fou_list, list) {
614 if (fou->port == port && fou->family == family) {
615 fou_release(fou);
616 err = 0;
617 break;
618 }
619 }
620 mutex_unlock(&fn->fou_lock);
621
622 return err;
623}
624
625static struct genl_family fou_nl_family;
626
627static const struct nla_policy fou_nl_policy[FOU_ATTR_MAX + 1] = {
628 [FOU_ATTR_PORT] = { .type = NLA_U16, },
629 [FOU_ATTR_AF] = { .type = NLA_U8, },
630 [FOU_ATTR_IPPROTO] = { .type = NLA_U8, },
631 [FOU_ATTR_TYPE] = { .type = NLA_U8, },
632 [FOU_ATTR_REMCSUM_NOPARTIAL] = { .type = NLA_FLAG, },
633};
634
635static int parse_nl_config(struct genl_info *info,
636 struct fou_cfg *cfg)
637{
638 memset(cfg, 0, sizeof(*cfg));
639
640 cfg->udp_config.family = AF_INET;
641
642 if (info->attrs[FOU_ATTR_AF]) {
643 u8 family = nla_get_u8(info->attrs[FOU_ATTR_AF]);
644
645 switch (family) {
646 case AF_INET:
647 break;
648 case AF_INET6:
649 cfg->udp_config.ipv6_v6only = 1;
650 break;
651 default:
652 return -EAFNOSUPPORT;
653 }
654
655 cfg->udp_config.family = family;
656 }
657
658 if (info->attrs[FOU_ATTR_PORT]) {
659 __be16 port = nla_get_be16(info->attrs[FOU_ATTR_PORT]);
660
661 cfg->udp_config.local_udp_port = port;
662 }
663
664 if (info->attrs[FOU_ATTR_IPPROTO])
665 cfg->protocol = nla_get_u8(info->attrs[FOU_ATTR_IPPROTO]);
666
667 if (info->attrs[FOU_ATTR_TYPE])
668 cfg->type = nla_get_u8(info->attrs[FOU_ATTR_TYPE]);
669
670 if (info->attrs[FOU_ATTR_REMCSUM_NOPARTIAL])
671 cfg->flags |= FOU_F_REMCSUM_NOPARTIAL;
672
673 return 0;
674}
675
676static int fou_nl_cmd_add_port(struct sk_buff *skb, struct genl_info *info)
677{
678 struct net *net = genl_info_net(info);
679 struct fou_cfg cfg;
680 int err;
681
682 err = parse_nl_config(info, &cfg);
683 if (err)
684 return err;
685
686 return fou_create(net, &cfg, NULL);
687}
688
689static int fou_nl_cmd_rm_port(struct sk_buff *skb, struct genl_info *info)
690{
691 struct net *net = genl_info_net(info);
692 struct fou_cfg cfg;
693 int err;
694
695 err = parse_nl_config(info, &cfg);
696 if (err)
697 return err;
698
699 return fou_destroy(net, &cfg);
700}
701
702static int fou_fill_info(struct fou *fou, struct sk_buff *msg)
703{
704 if (nla_put_u8(msg, FOU_ATTR_AF, fou->sock->sk->sk_family) ||
705 nla_put_be16(msg, FOU_ATTR_PORT, fou->port) ||
706 nla_put_u8(msg, FOU_ATTR_IPPROTO, fou->protocol) ||
707 nla_put_u8(msg, FOU_ATTR_TYPE, fou->type))
708 return -1;
709
710 if (fou->flags & FOU_F_REMCSUM_NOPARTIAL)
711 if (nla_put_flag(msg, FOU_ATTR_REMCSUM_NOPARTIAL))
712 return -1;
713 return 0;
714}
715
716static int fou_dump_info(struct fou *fou, u32 portid, u32 seq,
717 u32 flags, struct sk_buff *skb, u8 cmd)
718{
719 void *hdr;
720
721 hdr = genlmsg_put(skb, portid, seq, &fou_nl_family, flags, cmd);
722 if (!hdr)
723 return -ENOMEM;
724
725 if (fou_fill_info(fou, skb) < 0)
726 goto nla_put_failure;
727
728 genlmsg_end(skb, hdr);
729 return 0;
730
731nla_put_failure:
732 genlmsg_cancel(skb, hdr);
733 return -EMSGSIZE;
734}
735
736static int fou_nl_cmd_get_port(struct sk_buff *skb, struct genl_info *info)
737{
738 struct net *net = genl_info_net(info);
739 struct fou_net *fn = net_generic(net, fou_net_id);
740 struct sk_buff *msg;
741 struct fou_cfg cfg;
742 struct fou *fout;
743 __be16 port;
744 u8 family;
745 int ret;
746
747 ret = parse_nl_config(info, &cfg);
748 if (ret)
749 return ret;
750 port = cfg.udp_config.local_udp_port;
751 if (port == 0)
752 return -EINVAL;
753
754 family = cfg.udp_config.family;
755 if (family != AF_INET && family != AF_INET6)
756 return -EINVAL;
757
758 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
759 if (!msg)
760 return -ENOMEM;
761
762 ret = -ESRCH;
763 mutex_lock(&fn->fou_lock);
764 list_for_each_entry(fout, &fn->fou_list, list) {
765 if (port == fout->port && family == fout->family) {
766 ret = fou_dump_info(fout, info->snd_portid,
767 info->snd_seq, 0, msg,
768 info->genlhdr->cmd);
769 break;
770 }
771 }
772 mutex_unlock(&fn->fou_lock);
773 if (ret < 0)
774 goto out_free;
775
776 return genlmsg_reply(msg, info);
777
778out_free:
779 nlmsg_free(msg);
780 return ret;
781}
782
783static int fou_nl_dump(struct sk_buff *skb, struct netlink_callback *cb)
784{
785 struct net *net = sock_net(skb->sk);
786 struct fou_net *fn = net_generic(net, fou_net_id);
787 struct fou *fout;
788 int idx = 0, ret;
789
790 mutex_lock(&fn->fou_lock);
791 list_for_each_entry(fout, &fn->fou_list, list) {
792 if (idx++ < cb->args[0])
793 continue;
794 ret = fou_dump_info(fout, NETLINK_CB(cb->skb).portid,
795 cb->nlh->nlmsg_seq, NLM_F_MULTI,
796 skb, FOU_CMD_GET);
797 if (ret)
798 break;
799 }
800 mutex_unlock(&fn->fou_lock);
801
802 cb->args[0] = idx;
803 return skb->len;
804}
805
806static const struct genl_ops fou_nl_ops[] = {
807 {
808 .cmd = FOU_CMD_ADD,
809 .doit = fou_nl_cmd_add_port,
810 .policy = fou_nl_policy,
811 .flags = GENL_ADMIN_PERM,
812 },
813 {
814 .cmd = FOU_CMD_DEL,
815 .doit = fou_nl_cmd_rm_port,
816 .policy = fou_nl_policy,
817 .flags = GENL_ADMIN_PERM,
818 },
819 {
820 .cmd = FOU_CMD_GET,
821 .doit = fou_nl_cmd_get_port,
822 .dumpit = fou_nl_dump,
823 .policy = fou_nl_policy,
824 },
825};
826
827static struct genl_family fou_nl_family __ro_after_init = {
828 .hdrsize = 0,
829 .name = FOU_GENL_NAME,
830 .version = FOU_GENL_VERSION,
831 .maxattr = FOU_ATTR_MAX,
832 .netnsok = true,
833 .module = THIS_MODULE,
834 .ops = fou_nl_ops,
835 .n_ops = ARRAY_SIZE(fou_nl_ops),
836};
837
838size_t fou_encap_hlen(struct ip_tunnel_encap *e)
839{
840 return sizeof(struct udphdr);
841}
842EXPORT_SYMBOL(fou_encap_hlen);
843
844size_t gue_encap_hlen(struct ip_tunnel_encap *e)
845{
846 size_t len;
847 bool need_priv = false;
848
849 len = sizeof(struct udphdr) + sizeof(struct guehdr);
850
851 if (e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) {
852 len += GUE_PLEN_REMCSUM;
853 need_priv = true;
854 }
855
856 len += need_priv ? GUE_LEN_PRIV : 0;
857
858 return len;
859}
860EXPORT_SYMBOL(gue_encap_hlen);
861
862static void fou_build_udp(struct sk_buff *skb, struct ip_tunnel_encap *e,
863 struct flowi4 *fl4, u8 *protocol, __be16 sport)
864{
865 struct udphdr *uh;
866
867 skb_push(skb, sizeof(struct udphdr));
868 skb_reset_transport_header(skb);
869
870 uh = udp_hdr(skb);
871
872 uh->dest = e->dport;
873 uh->source = sport;
874 uh->len = htons(skb->len);
875 udp_set_csum(!(e->flags & TUNNEL_ENCAP_FLAG_CSUM), skb,
876 fl4->saddr, fl4->daddr, skb->len);
877
878 *protocol = IPPROTO_UDP;
879}
880
881int __fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
882 u8 *protocol, __be16 *sport, int type)
883{
884 int err;
885
886 err = iptunnel_handle_offloads(skb, type);
887 if (err)
888 return err;
889
890 *sport = e->sport ? : udp_flow_src_port(dev_net(skb->dev),
891 skb, 0, 0, false);
892
893 return 0;
894}
895EXPORT_SYMBOL(__fou_build_header);
896
897int fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
898 u8 *protocol, struct flowi4 *fl4)
899{
900 int type = e->flags & TUNNEL_ENCAP_FLAG_CSUM ? SKB_GSO_UDP_TUNNEL_CSUM :
901 SKB_GSO_UDP_TUNNEL;
902 __be16 sport;
903 int err;
904
905 err = __fou_build_header(skb, e, protocol, &sport, type);
906 if (err)
907 return err;
908
909 fou_build_udp(skb, e, fl4, protocol, sport);
910
911 return 0;
912}
913EXPORT_SYMBOL(fou_build_header);
914
915int __gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
916 u8 *protocol, __be16 *sport, int type)
917{
918 struct guehdr *guehdr;
919 size_t hdrlen, optlen = 0;
920 void *data;
921 bool need_priv = false;
922 int err;
923
924 if ((e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) &&
925 skb->ip_summed == CHECKSUM_PARTIAL) {
926 optlen += GUE_PLEN_REMCSUM;
927 type |= SKB_GSO_TUNNEL_REMCSUM;
928 need_priv = true;
929 }
930
931 optlen += need_priv ? GUE_LEN_PRIV : 0;
932
933 err = iptunnel_handle_offloads(skb, type);
934 if (err)
935 return err;
936
937 /* Get source port (based on flow hash) before skb_push */
938 *sport = e->sport ? : udp_flow_src_port(dev_net(skb->dev),
939 skb, 0, 0, false);
940
941 hdrlen = sizeof(struct guehdr) + optlen;
942
943 skb_push(skb, hdrlen);
944
945 guehdr = (struct guehdr *)skb->data;
946
947 guehdr->control = 0;
948 guehdr->version = 0;
949 guehdr->hlen = optlen >> 2;
950 guehdr->flags = 0;
951 guehdr->proto_ctype = *protocol;
952
953 data = &guehdr[1];
954
955 if (need_priv) {
956 __be32 *flags = data;
957
958 guehdr->flags |= GUE_FLAG_PRIV;
959 *flags = 0;
960 data += GUE_LEN_PRIV;
961
962 if (type & SKB_GSO_TUNNEL_REMCSUM) {
963 u16 csum_start = skb_checksum_start_offset(skb);
964 __be16 *pd = data;
965
966 if (csum_start < hdrlen)
967 return -EINVAL;
968
969 csum_start -= hdrlen;
970 pd[0] = htons(csum_start);
971 pd[1] = htons(csum_start + skb->csum_offset);
972
973 if (!skb_is_gso(skb)) {
974 skb->ip_summed = CHECKSUM_NONE;
975 skb->encapsulation = 0;
976 }
977
978 *flags |= GUE_PFLAG_REMCSUM;
979 data += GUE_PLEN_REMCSUM;
980 }
981
982 }
983
984 return 0;
985}
986EXPORT_SYMBOL(__gue_build_header);
987
988int gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
989 u8 *protocol, struct flowi4 *fl4)
990{
991 int type = e->flags & TUNNEL_ENCAP_FLAG_CSUM ? SKB_GSO_UDP_TUNNEL_CSUM :
992 SKB_GSO_UDP_TUNNEL;
993 __be16 sport;
994 int err;
995
996 err = __gue_build_header(skb, e, protocol, &sport, type);
997 if (err)
998 return err;
999
1000 fou_build_udp(skb, e, fl4, protocol, sport);
1001
1002 return 0;
1003}
1004EXPORT_SYMBOL(gue_build_header);
1005
1006#ifdef CONFIG_NET_FOU_IP_TUNNELS
1007
1008static const struct ip_tunnel_encap_ops fou_iptun_ops = {
1009 .encap_hlen = fou_encap_hlen,
1010 .build_header = fou_build_header,
1011};
1012
1013static const struct ip_tunnel_encap_ops gue_iptun_ops = {
1014 .encap_hlen = gue_encap_hlen,
1015 .build_header = gue_build_header,
1016};
1017
1018static int ip_tunnel_encap_add_fou_ops(void)
1019{
1020 int ret;
1021
1022 ret = ip_tunnel_encap_add_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
1023 if (ret < 0) {
1024 pr_err("can't add fou ops\n");
1025 return ret;
1026 }
1027
1028 ret = ip_tunnel_encap_add_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE);
1029 if (ret < 0) {
1030 pr_err("can't add gue ops\n");
1031 ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
1032 return ret;
1033 }
1034
1035 return 0;
1036}
1037
1038static void ip_tunnel_encap_del_fou_ops(void)
1039{
1040 ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
1041 ip_tunnel_encap_del_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE);
1042}
1043
1044#else
1045
1046static int ip_tunnel_encap_add_fou_ops(void)
1047{
1048 return 0;
1049}
1050
1051static void ip_tunnel_encap_del_fou_ops(void)
1052{
1053}
1054
1055#endif
1056
1057static __net_init int fou_init_net(struct net *net)
1058{
1059 struct fou_net *fn = net_generic(net, fou_net_id);
1060
1061 INIT_LIST_HEAD(&fn->fou_list);
1062 mutex_init(&fn->fou_lock);
1063 return 0;
1064}
1065
1066static __net_exit void fou_exit_net(struct net *net)
1067{
1068 struct fou_net *fn = net_generic(net, fou_net_id);
1069 struct fou *fou, *next;
1070
1071 /* Close all the FOU sockets */
1072 mutex_lock(&fn->fou_lock);
1073 list_for_each_entry_safe(fou, next, &fn->fou_list, list)
1074 fou_release(fou);
1075 mutex_unlock(&fn->fou_lock);
1076}
1077
1078static struct pernet_operations fou_net_ops = {
1079 .init = fou_init_net,
1080 .exit = fou_exit_net,
1081 .id = &fou_net_id,
1082 .size = sizeof(struct fou_net),
1083};
1084
1085static int __init fou_init(void)
1086{
1087 int ret;
1088
1089 ret = register_pernet_device(&fou_net_ops);
1090 if (ret)
1091 goto exit;
1092
1093 ret = genl_register_family(&fou_nl_family);
1094 if (ret < 0)
1095 goto unregister;
1096
1097 ret = ip_tunnel_encap_add_fou_ops();
1098 if (ret == 0)
1099 return 0;
1100
1101 genl_unregister_family(&fou_nl_family);
1102unregister:
1103 unregister_pernet_device(&fou_net_ops);
1104exit:
1105 return ret;
1106}
1107
1108static void __exit fou_fini(void)
1109{
1110 ip_tunnel_encap_del_fou_ops();
1111 genl_unregister_family(&fou_nl_family);
1112 unregister_pernet_device(&fou_net_ops);
1113}
1114
1115module_init(fou_init);
1116module_exit(fou_fini);
1117MODULE_AUTHOR("Tom Herbert <therbert@google.com>");
1118MODULE_LICENSE("GPL");