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15#include <linux/types.h>
16#include <linux/skbuff.h>
17#include <linux/net.h>
18#include <linux/module.h>
19#include <net/ip.h>
20#include <net/lwtunnel.h>
21#include <net/netevent.h>
22#include <net/netns/generic.h>
23#include <net/ip6_fib.h>
24#include <net/route.h>
25#include <net/seg6.h>
26#include <linux/seg6.h>
27#include <linux/seg6_local.h>
28#include <net/addrconf.h>
29#include <net/ip6_route.h>
30#include <net/dst_cache.h>
31#ifdef CONFIG_IPV6_SEG6_HMAC
32#include <net/seg6_hmac.h>
33#endif
34#include <net/seg6_local.h>
35#include <linux/etherdevice.h>
36#include <linux/bpf.h>
37
38struct seg6_local_lwt;
39
40struct seg6_action_desc {
41 int action;
42 unsigned long attrs;
43 int (*input)(struct sk_buff *skb, struct seg6_local_lwt *slwt);
44 int static_headroom;
45};
46
47struct bpf_lwt_prog {
48 struct bpf_prog *prog;
49 char *name;
50};
51
52struct seg6_local_lwt {
53 int action;
54 struct ipv6_sr_hdr *srh;
55 int table;
56 struct in_addr nh4;
57 struct in6_addr nh6;
58 int iif;
59 int oif;
60 struct bpf_lwt_prog bpf;
61
62 int headroom;
63 struct seg6_action_desc *desc;
64};
65
66static struct seg6_local_lwt *seg6_local_lwtunnel(struct lwtunnel_state *lwt)
67{
68 return (struct seg6_local_lwt *)lwt->data;
69}
70
71static struct ipv6_sr_hdr *get_srh(struct sk_buff *skb)
72{
73 struct ipv6_sr_hdr *srh;
74 int len, srhoff = 0;
75
76 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
77 return NULL;
78
79 if (!pskb_may_pull(skb, srhoff + sizeof(*srh)))
80 return NULL;
81
82 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
83
84 len = (srh->hdrlen + 1) << 3;
85
86 if (!pskb_may_pull(skb, srhoff + len))
87 return NULL;
88
89 if (!seg6_validate_srh(srh, len))
90 return NULL;
91
92 return srh;
93}
94
95static struct ipv6_sr_hdr *get_and_validate_srh(struct sk_buff *skb)
96{
97 struct ipv6_sr_hdr *srh;
98
99 srh = get_srh(skb);
100 if (!srh)
101 return NULL;
102
103 if (srh->segments_left == 0)
104 return NULL;
105
106#ifdef CONFIG_IPV6_SEG6_HMAC
107 if (!seg6_hmac_validate_skb(skb))
108 return NULL;
109#endif
110
111 return srh;
112}
113
114static bool decap_and_validate(struct sk_buff *skb, int proto)
115{
116 struct ipv6_sr_hdr *srh;
117 unsigned int off = 0;
118
119 srh = get_srh(skb);
120 if (srh && srh->segments_left > 0)
121 return false;
122
123#ifdef CONFIG_IPV6_SEG6_HMAC
124 if (srh && !seg6_hmac_validate_skb(skb))
125 return false;
126#endif
127
128 if (ipv6_find_hdr(skb, &off, proto, NULL, NULL) < 0)
129 return false;
130
131 if (!pskb_pull(skb, off))
132 return false;
133
134 skb_postpull_rcsum(skb, skb_network_header(skb), off);
135
136 skb_reset_network_header(skb);
137 skb_reset_transport_header(skb);
138 skb->encapsulation = 0;
139
140 return true;
141}
142
143static void advance_nextseg(struct ipv6_sr_hdr *srh, struct in6_addr *daddr)
144{
145 struct in6_addr *addr;
146
147 srh->segments_left--;
148 addr = srh->segments + srh->segments_left;
149 *daddr = *addr;
150}
151
152int seg6_lookup_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
153 u32 tbl_id)
154{
155 struct net *net = dev_net(skb->dev);
156 struct ipv6hdr *hdr = ipv6_hdr(skb);
157 int flags = RT6_LOOKUP_F_HAS_SADDR;
158 struct dst_entry *dst = NULL;
159 struct rt6_info *rt;
160 struct flowi6 fl6;
161
162 fl6.flowi6_iif = skb->dev->ifindex;
163 fl6.daddr = nhaddr ? *nhaddr : hdr->daddr;
164 fl6.saddr = hdr->saddr;
165 fl6.flowlabel = ip6_flowinfo(hdr);
166 fl6.flowi6_mark = skb->mark;
167 fl6.flowi6_proto = hdr->nexthdr;
168
169 if (nhaddr)
170 fl6.flowi6_flags = FLOWI_FLAG_KNOWN_NH;
171
172 if (!tbl_id) {
173 dst = ip6_route_input_lookup(net, skb->dev, &fl6, skb, flags);
174 } else {
175 struct fib6_table *table;
176
177 table = fib6_get_table(net, tbl_id);
178 if (!table)
179 goto out;
180
181 rt = ip6_pol_route(net, table, 0, &fl6, skb, flags);
182 dst = &rt->dst;
183 }
184
185 if (dst && dst->dev->flags & IFF_LOOPBACK && !dst->error) {
186 dst_release(dst);
187 dst = NULL;
188 }
189
190out:
191 if (!dst) {
192 rt = net->ipv6.ip6_blk_hole_entry;
193 dst = &rt->dst;
194 dst_hold(dst);
195 }
196
197 skb_dst_drop(skb);
198 skb_dst_set(skb, dst);
199 return dst->error;
200}
201
202
203static int input_action_end(struct sk_buff *skb, struct seg6_local_lwt *slwt)
204{
205 struct ipv6_sr_hdr *srh;
206
207 srh = get_and_validate_srh(skb);
208 if (!srh)
209 goto drop;
210
211 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
212
213 seg6_lookup_nexthop(skb, NULL, 0);
214
215 return dst_input(skb);
216
217drop:
218 kfree_skb(skb);
219 return -EINVAL;
220}
221
222
223static int input_action_end_x(struct sk_buff *skb, struct seg6_local_lwt *slwt)
224{
225 struct ipv6_sr_hdr *srh;
226
227 srh = get_and_validate_srh(skb);
228 if (!srh)
229 goto drop;
230
231 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
232
233 seg6_lookup_nexthop(skb, &slwt->nh6, 0);
234
235 return dst_input(skb);
236
237drop:
238 kfree_skb(skb);
239 return -EINVAL;
240}
241
242static int input_action_end_t(struct sk_buff *skb, struct seg6_local_lwt *slwt)
243{
244 struct ipv6_sr_hdr *srh;
245
246 srh = get_and_validate_srh(skb);
247 if (!srh)
248 goto drop;
249
250 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
251
252 seg6_lookup_nexthop(skb, NULL, slwt->table);
253
254 return dst_input(skb);
255
256drop:
257 kfree_skb(skb);
258 return -EINVAL;
259}
260
261
262static int input_action_end_dx2(struct sk_buff *skb,
263 struct seg6_local_lwt *slwt)
264{
265 struct net *net = dev_net(skb->dev);
266 struct net_device *odev;
267 struct ethhdr *eth;
268
269 if (!decap_and_validate(skb, NEXTHDR_NONE))
270 goto drop;
271
272 if (!pskb_may_pull(skb, ETH_HLEN))
273 goto drop;
274
275 skb_reset_mac_header(skb);
276 eth = (struct ethhdr *)skb->data;
277
278
279
280
281
282 if (!eth_proto_is_802_3(eth->h_proto))
283 goto drop;
284
285 odev = dev_get_by_index_rcu(net, slwt->oif);
286 if (!odev)
287 goto drop;
288
289
290
291
292 if (odev->type != ARPHRD_ETHER)
293 goto drop;
294
295 if (!(odev->flags & IFF_UP) || !netif_carrier_ok(odev))
296 goto drop;
297
298 skb_orphan(skb);
299
300 if (skb_warn_if_lro(skb))
301 goto drop;
302
303 skb_forward_csum(skb);
304
305 if (skb->len - ETH_HLEN > odev->mtu)
306 goto drop;
307
308 skb->dev = odev;
309 skb->protocol = eth->h_proto;
310
311 return dev_queue_xmit(skb);
312
313drop:
314 kfree_skb(skb);
315 return -EINVAL;
316}
317
318
319static int input_action_end_dx6(struct sk_buff *skb,
320 struct seg6_local_lwt *slwt)
321{
322 struct in6_addr *nhaddr = NULL;
323
324
325
326
327
328 if (!decap_and_validate(skb, IPPROTO_IPV6))
329 goto drop;
330
331 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
332 goto drop;
333
334
335
336
337
338
339
340
341 if (!ipv6_addr_any(&slwt->nh6))
342 nhaddr = &slwt->nh6;
343
344 seg6_lookup_nexthop(skb, nhaddr, 0);
345
346 return dst_input(skb);
347drop:
348 kfree_skb(skb);
349 return -EINVAL;
350}
351
352static int input_action_end_dx4(struct sk_buff *skb,
353 struct seg6_local_lwt *slwt)
354{
355 struct iphdr *iph;
356 __be32 nhaddr;
357 int err;
358
359 if (!decap_and_validate(skb, IPPROTO_IPIP))
360 goto drop;
361
362 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
363 goto drop;
364
365 skb->protocol = htons(ETH_P_IP);
366
367 iph = ip_hdr(skb);
368
369 nhaddr = slwt->nh4.s_addr ?: iph->daddr;
370
371 skb_dst_drop(skb);
372
373 err = ip_route_input(skb, nhaddr, iph->saddr, 0, skb->dev);
374 if (err)
375 goto drop;
376
377 return dst_input(skb);
378
379drop:
380 kfree_skb(skb);
381 return -EINVAL;
382}
383
384static int input_action_end_dt6(struct sk_buff *skb,
385 struct seg6_local_lwt *slwt)
386{
387 if (!decap_and_validate(skb, IPPROTO_IPV6))
388 goto drop;
389
390 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
391 goto drop;
392
393 seg6_lookup_nexthop(skb, NULL, slwt->table);
394
395 return dst_input(skb);
396
397drop:
398 kfree_skb(skb);
399 return -EINVAL;
400}
401
402
403static int input_action_end_b6(struct sk_buff *skb, struct seg6_local_lwt *slwt)
404{
405 struct ipv6_sr_hdr *srh;
406 int err = -EINVAL;
407
408 srh = get_and_validate_srh(skb);
409 if (!srh)
410 goto drop;
411
412 err = seg6_do_srh_inline(skb, slwt->srh);
413 if (err)
414 goto drop;
415
416 ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
417 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
418
419 seg6_lookup_nexthop(skb, NULL, 0);
420
421 return dst_input(skb);
422
423drop:
424 kfree_skb(skb);
425 return err;
426}
427
428
429static int input_action_end_b6_encap(struct sk_buff *skb,
430 struct seg6_local_lwt *slwt)
431{
432 struct ipv6_sr_hdr *srh;
433 int err = -EINVAL;
434
435 srh = get_and_validate_srh(skb);
436 if (!srh)
437 goto drop;
438
439 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
440
441 skb_reset_inner_headers(skb);
442 skb->encapsulation = 1;
443
444 err = seg6_do_srh_encap(skb, slwt->srh, IPPROTO_IPV6);
445 if (err)
446 goto drop;
447
448 ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
449 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
450
451 seg6_lookup_nexthop(skb, NULL, 0);
452
453 return dst_input(skb);
454
455drop:
456 kfree_skb(skb);
457 return err;
458}
459
460DEFINE_PER_CPU(struct seg6_bpf_srh_state, seg6_bpf_srh_states);
461
462bool seg6_bpf_has_valid_srh(struct sk_buff *skb)
463{
464 struct seg6_bpf_srh_state *srh_state =
465 this_cpu_ptr(&seg6_bpf_srh_states);
466 struct ipv6_sr_hdr *srh = srh_state->srh;
467
468 if (unlikely(srh == NULL))
469 return false;
470
471 if (unlikely(!srh_state->valid)) {
472 if ((srh_state->hdrlen & 7) != 0)
473 return false;
474
475 srh->hdrlen = (u8)(srh_state->hdrlen >> 3);
476 if (!seg6_validate_srh(srh, (srh->hdrlen + 1) << 3))
477 return false;
478
479 srh_state->valid = true;
480 }
481
482 return true;
483}
484
485static int input_action_end_bpf(struct sk_buff *skb,
486 struct seg6_local_lwt *slwt)
487{
488 struct seg6_bpf_srh_state *srh_state =
489 this_cpu_ptr(&seg6_bpf_srh_states);
490 struct ipv6_sr_hdr *srh;
491 int ret;
492
493 srh = get_and_validate_srh(skb);
494 if (!srh) {
495 kfree_skb(skb);
496 return -EINVAL;
497 }
498 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
499
500
501
502
503 preempt_disable();
504 srh_state->srh = srh;
505 srh_state->hdrlen = srh->hdrlen << 3;
506 srh_state->valid = true;
507
508 rcu_read_lock();
509 bpf_compute_data_pointers(skb);
510 ret = bpf_prog_run_save_cb(slwt->bpf.prog, skb);
511 rcu_read_unlock();
512
513 switch (ret) {
514 case BPF_OK:
515 case BPF_REDIRECT:
516 break;
517 case BPF_DROP:
518 goto drop;
519 default:
520 pr_warn_once("bpf-seg6local: Illegal return value %u\n", ret);
521 goto drop;
522 }
523
524 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
525 goto drop;
526
527 preempt_enable();
528 if (ret != BPF_REDIRECT)
529 seg6_lookup_nexthop(skb, NULL, 0);
530
531 return dst_input(skb);
532
533drop:
534 preempt_enable();
535 kfree_skb(skb);
536 return -EINVAL;
537}
538
539static struct seg6_action_desc seg6_action_table[] = {
540 {
541 .action = SEG6_LOCAL_ACTION_END,
542 .attrs = 0,
543 .input = input_action_end,
544 },
545 {
546 .action = SEG6_LOCAL_ACTION_END_X,
547 .attrs = (1 << SEG6_LOCAL_NH6),
548 .input = input_action_end_x,
549 },
550 {
551 .action = SEG6_LOCAL_ACTION_END_T,
552 .attrs = (1 << SEG6_LOCAL_TABLE),
553 .input = input_action_end_t,
554 },
555 {
556 .action = SEG6_LOCAL_ACTION_END_DX2,
557 .attrs = (1 << SEG6_LOCAL_OIF),
558 .input = input_action_end_dx2,
559 },
560 {
561 .action = SEG6_LOCAL_ACTION_END_DX6,
562 .attrs = (1 << SEG6_LOCAL_NH6),
563 .input = input_action_end_dx6,
564 },
565 {
566 .action = SEG6_LOCAL_ACTION_END_DX4,
567 .attrs = (1 << SEG6_LOCAL_NH4),
568 .input = input_action_end_dx4,
569 },
570 {
571 .action = SEG6_LOCAL_ACTION_END_DT6,
572 .attrs = (1 << SEG6_LOCAL_TABLE),
573 .input = input_action_end_dt6,
574 },
575 {
576 .action = SEG6_LOCAL_ACTION_END_B6,
577 .attrs = (1 << SEG6_LOCAL_SRH),
578 .input = input_action_end_b6,
579 },
580 {
581 .action = SEG6_LOCAL_ACTION_END_B6_ENCAP,
582 .attrs = (1 << SEG6_LOCAL_SRH),
583 .input = input_action_end_b6_encap,
584 .static_headroom = sizeof(struct ipv6hdr),
585 },
586 {
587 .action = SEG6_LOCAL_ACTION_END_BPF,
588 .attrs = (1 << SEG6_LOCAL_BPF),
589 .input = input_action_end_bpf,
590 },
591
592};
593
594static struct seg6_action_desc *__get_action_desc(int action)
595{
596 struct seg6_action_desc *desc;
597 int i, count;
598
599 count = ARRAY_SIZE(seg6_action_table);
600 for (i = 0; i < count; i++) {
601 desc = &seg6_action_table[i];
602 if (desc->action == action)
603 return desc;
604 }
605
606 return NULL;
607}
608
609static int seg6_local_input(struct sk_buff *skb)
610{
611 struct dst_entry *orig_dst = skb_dst(skb);
612 struct seg6_action_desc *desc;
613 struct seg6_local_lwt *slwt;
614
615 if (skb->protocol != htons(ETH_P_IPV6)) {
616 kfree_skb(skb);
617 return -EINVAL;
618 }
619
620 slwt = seg6_local_lwtunnel(orig_dst->lwtstate);
621 desc = slwt->desc;
622
623 return desc->input(skb, slwt);
624}
625
626static const struct nla_policy seg6_local_policy[SEG6_LOCAL_MAX + 1] = {
627 [SEG6_LOCAL_ACTION] = { .type = NLA_U32 },
628 [SEG6_LOCAL_SRH] = { .type = NLA_BINARY },
629 [SEG6_LOCAL_TABLE] = { .type = NLA_U32 },
630 [SEG6_LOCAL_NH4] = { .type = NLA_BINARY,
631 .len = sizeof(struct in_addr) },
632 [SEG6_LOCAL_NH6] = { .type = NLA_BINARY,
633 .len = sizeof(struct in6_addr) },
634 [SEG6_LOCAL_IIF] = { .type = NLA_U32 },
635 [SEG6_LOCAL_OIF] = { .type = NLA_U32 },
636 [SEG6_LOCAL_BPF] = { .type = NLA_NESTED },
637};
638
639static int parse_nla_srh(struct nlattr **attrs, struct seg6_local_lwt *slwt)
640{
641 struct ipv6_sr_hdr *srh;
642 int len;
643
644 srh = nla_data(attrs[SEG6_LOCAL_SRH]);
645 len = nla_len(attrs[SEG6_LOCAL_SRH]);
646
647
648 if (len < sizeof(*srh) + sizeof(struct in6_addr))
649 return -EINVAL;
650
651 if (!seg6_validate_srh(srh, len))
652 return -EINVAL;
653
654 slwt->srh = kmemdup(srh, len, GFP_KERNEL);
655 if (!slwt->srh)
656 return -ENOMEM;
657
658 slwt->headroom += len;
659
660 return 0;
661}
662
663static int put_nla_srh(struct sk_buff *skb, struct seg6_local_lwt *slwt)
664{
665 struct ipv6_sr_hdr *srh;
666 struct nlattr *nla;
667 int len;
668
669 srh = slwt->srh;
670 len = (srh->hdrlen + 1) << 3;
671
672 nla = nla_reserve(skb, SEG6_LOCAL_SRH, len);
673 if (!nla)
674 return -EMSGSIZE;
675
676 memcpy(nla_data(nla), srh, len);
677
678 return 0;
679}
680
681static int cmp_nla_srh(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
682{
683 int len = (a->srh->hdrlen + 1) << 3;
684
685 if (len != ((b->srh->hdrlen + 1) << 3))
686 return 1;
687
688 return memcmp(a->srh, b->srh, len);
689}
690
691static int parse_nla_table(struct nlattr **attrs, struct seg6_local_lwt *slwt)
692{
693 slwt->table = nla_get_u32(attrs[SEG6_LOCAL_TABLE]);
694
695 return 0;
696}
697
698static int put_nla_table(struct sk_buff *skb, struct seg6_local_lwt *slwt)
699{
700 if (nla_put_u32(skb, SEG6_LOCAL_TABLE, slwt->table))
701 return -EMSGSIZE;
702
703 return 0;
704}
705
706static int cmp_nla_table(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
707{
708 if (a->table != b->table)
709 return 1;
710
711 return 0;
712}
713
714static int parse_nla_nh4(struct nlattr **attrs, struct seg6_local_lwt *slwt)
715{
716 memcpy(&slwt->nh4, nla_data(attrs[SEG6_LOCAL_NH4]),
717 sizeof(struct in_addr));
718
719 return 0;
720}
721
722static int put_nla_nh4(struct sk_buff *skb, struct seg6_local_lwt *slwt)
723{
724 struct nlattr *nla;
725
726 nla = nla_reserve(skb, SEG6_LOCAL_NH4, sizeof(struct in_addr));
727 if (!nla)
728 return -EMSGSIZE;
729
730 memcpy(nla_data(nla), &slwt->nh4, sizeof(struct in_addr));
731
732 return 0;
733}
734
735static int cmp_nla_nh4(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
736{
737 return memcmp(&a->nh4, &b->nh4, sizeof(struct in_addr));
738}
739
740static int parse_nla_nh6(struct nlattr **attrs, struct seg6_local_lwt *slwt)
741{
742 memcpy(&slwt->nh6, nla_data(attrs[SEG6_LOCAL_NH6]),
743 sizeof(struct in6_addr));
744
745 return 0;
746}
747
748static int put_nla_nh6(struct sk_buff *skb, struct seg6_local_lwt *slwt)
749{
750 struct nlattr *nla;
751
752 nla = nla_reserve(skb, SEG6_LOCAL_NH6, sizeof(struct in6_addr));
753 if (!nla)
754 return -EMSGSIZE;
755
756 memcpy(nla_data(nla), &slwt->nh6, sizeof(struct in6_addr));
757
758 return 0;
759}
760
761static int cmp_nla_nh6(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
762{
763 return memcmp(&a->nh6, &b->nh6, sizeof(struct in6_addr));
764}
765
766static int parse_nla_iif(struct nlattr **attrs, struct seg6_local_lwt *slwt)
767{
768 slwt->iif = nla_get_u32(attrs[SEG6_LOCAL_IIF]);
769
770 return 0;
771}
772
773static int put_nla_iif(struct sk_buff *skb, struct seg6_local_lwt *slwt)
774{
775 if (nla_put_u32(skb, SEG6_LOCAL_IIF, slwt->iif))
776 return -EMSGSIZE;
777
778 return 0;
779}
780
781static int cmp_nla_iif(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
782{
783 if (a->iif != b->iif)
784 return 1;
785
786 return 0;
787}
788
789static int parse_nla_oif(struct nlattr **attrs, struct seg6_local_lwt *slwt)
790{
791 slwt->oif = nla_get_u32(attrs[SEG6_LOCAL_OIF]);
792
793 return 0;
794}
795
796static int put_nla_oif(struct sk_buff *skb, struct seg6_local_lwt *slwt)
797{
798 if (nla_put_u32(skb, SEG6_LOCAL_OIF, slwt->oif))
799 return -EMSGSIZE;
800
801 return 0;
802}
803
804static int cmp_nla_oif(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
805{
806 if (a->oif != b->oif)
807 return 1;
808
809 return 0;
810}
811
812#define MAX_PROG_NAME 256
813static const struct nla_policy bpf_prog_policy[SEG6_LOCAL_BPF_PROG_MAX + 1] = {
814 [SEG6_LOCAL_BPF_PROG] = { .type = NLA_U32, },
815 [SEG6_LOCAL_BPF_PROG_NAME] = { .type = NLA_NUL_STRING,
816 .len = MAX_PROG_NAME },
817};
818
819static int parse_nla_bpf(struct nlattr **attrs, struct seg6_local_lwt *slwt)
820{
821 struct nlattr *tb[SEG6_LOCAL_BPF_PROG_MAX + 1];
822 struct bpf_prog *p;
823 int ret;
824 u32 fd;
825
826 ret = nla_parse_nested(tb, SEG6_LOCAL_BPF_PROG_MAX,
827 attrs[SEG6_LOCAL_BPF], bpf_prog_policy, NULL);
828 if (ret < 0)
829 return ret;
830
831 if (!tb[SEG6_LOCAL_BPF_PROG] || !tb[SEG6_LOCAL_BPF_PROG_NAME])
832 return -EINVAL;
833
834 slwt->bpf.name = nla_memdup(tb[SEG6_LOCAL_BPF_PROG_NAME], GFP_KERNEL);
835 if (!slwt->bpf.name)
836 return -ENOMEM;
837
838 fd = nla_get_u32(tb[SEG6_LOCAL_BPF_PROG]);
839 p = bpf_prog_get_type(fd, BPF_PROG_TYPE_LWT_SEG6LOCAL);
840 if (IS_ERR(p)) {
841 kfree(slwt->bpf.name);
842 return PTR_ERR(p);
843 }
844
845 slwt->bpf.prog = p;
846 return 0;
847}
848
849static int put_nla_bpf(struct sk_buff *skb, struct seg6_local_lwt *slwt)
850{
851 struct nlattr *nest;
852
853 if (!slwt->bpf.prog)
854 return 0;
855
856 nest = nla_nest_start(skb, SEG6_LOCAL_BPF);
857 if (!nest)
858 return -EMSGSIZE;
859
860 if (nla_put_u32(skb, SEG6_LOCAL_BPF_PROG, slwt->bpf.prog->aux->id))
861 return -EMSGSIZE;
862
863 if (slwt->bpf.name &&
864 nla_put_string(skb, SEG6_LOCAL_BPF_PROG_NAME, slwt->bpf.name))
865 return -EMSGSIZE;
866
867 return nla_nest_end(skb, nest);
868}
869
870static int cmp_nla_bpf(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
871{
872 if (!a->bpf.name && !b->bpf.name)
873 return 0;
874
875 if (!a->bpf.name || !b->bpf.name)
876 return 1;
877
878 return strcmp(a->bpf.name, b->bpf.name);
879}
880
881struct seg6_action_param {
882 int (*parse)(struct nlattr **attrs, struct seg6_local_lwt *slwt);
883 int (*put)(struct sk_buff *skb, struct seg6_local_lwt *slwt);
884 int (*cmp)(struct seg6_local_lwt *a, struct seg6_local_lwt *b);
885};
886
887static struct seg6_action_param seg6_action_params[SEG6_LOCAL_MAX + 1] = {
888 [SEG6_LOCAL_SRH] = { .parse = parse_nla_srh,
889 .put = put_nla_srh,
890 .cmp = cmp_nla_srh },
891
892 [SEG6_LOCAL_TABLE] = { .parse = parse_nla_table,
893 .put = put_nla_table,
894 .cmp = cmp_nla_table },
895
896 [SEG6_LOCAL_NH4] = { .parse = parse_nla_nh4,
897 .put = put_nla_nh4,
898 .cmp = cmp_nla_nh4 },
899
900 [SEG6_LOCAL_NH6] = { .parse = parse_nla_nh6,
901 .put = put_nla_nh6,
902 .cmp = cmp_nla_nh6 },
903
904 [SEG6_LOCAL_IIF] = { .parse = parse_nla_iif,
905 .put = put_nla_iif,
906 .cmp = cmp_nla_iif },
907
908 [SEG6_LOCAL_OIF] = { .parse = parse_nla_oif,
909 .put = put_nla_oif,
910 .cmp = cmp_nla_oif },
911
912 [SEG6_LOCAL_BPF] = { .parse = parse_nla_bpf,
913 .put = put_nla_bpf,
914 .cmp = cmp_nla_bpf },
915
916};
917
918static int parse_nla_action(struct nlattr **attrs, struct seg6_local_lwt *slwt)
919{
920 struct seg6_action_param *param;
921 struct seg6_action_desc *desc;
922 int i, err;
923
924 desc = __get_action_desc(slwt->action);
925 if (!desc)
926 return -EINVAL;
927
928 if (!desc->input)
929 return -EOPNOTSUPP;
930
931 slwt->desc = desc;
932 slwt->headroom += desc->static_headroom;
933
934 for (i = 0; i < SEG6_LOCAL_MAX + 1; i++) {
935 if (desc->attrs & (1 << i)) {
936 if (!attrs[i])
937 return -EINVAL;
938
939 param = &seg6_action_params[i];
940
941 err = param->parse(attrs, slwt);
942 if (err < 0)
943 return err;
944 }
945 }
946
947 return 0;
948}
949
950static int seg6_local_build_state(struct nlattr *nla, unsigned int family,
951 const void *cfg, struct lwtunnel_state **ts,
952 struct netlink_ext_ack *extack)
953{
954 struct nlattr *tb[SEG6_LOCAL_MAX + 1];
955 struct lwtunnel_state *newts;
956 struct seg6_local_lwt *slwt;
957 int err;
958
959 if (family != AF_INET6)
960 return -EINVAL;
961
962 err = nla_parse_nested(tb, SEG6_LOCAL_MAX, nla, seg6_local_policy,
963 extack);
964
965 if (err < 0)
966 return err;
967
968 if (!tb[SEG6_LOCAL_ACTION])
969 return -EINVAL;
970
971 newts = lwtunnel_state_alloc(sizeof(*slwt));
972 if (!newts)
973 return -ENOMEM;
974
975 slwt = seg6_local_lwtunnel(newts);
976 slwt->action = nla_get_u32(tb[SEG6_LOCAL_ACTION]);
977
978 err = parse_nla_action(tb, slwt);
979 if (err < 0)
980 goto out_free;
981
982 newts->type = LWTUNNEL_ENCAP_SEG6_LOCAL;
983 newts->flags = LWTUNNEL_STATE_INPUT_REDIRECT;
984 newts->headroom = slwt->headroom;
985
986 *ts = newts;
987
988 return 0;
989
990out_free:
991 kfree(slwt->srh);
992 kfree(newts);
993 return err;
994}
995
996static void seg6_local_destroy_state(struct lwtunnel_state *lwt)
997{
998 struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
999
1000 kfree(slwt->srh);
1001
1002 if (slwt->desc->attrs & (1 << SEG6_LOCAL_BPF)) {
1003 kfree(slwt->bpf.name);
1004 bpf_prog_put(slwt->bpf.prog);
1005 }
1006
1007 return;
1008}
1009
1010static int seg6_local_fill_encap(struct sk_buff *skb,
1011 struct lwtunnel_state *lwt)
1012{
1013 struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
1014 struct seg6_action_param *param;
1015 int i, err;
1016
1017 if (nla_put_u32(skb, SEG6_LOCAL_ACTION, slwt->action))
1018 return -EMSGSIZE;
1019
1020 for (i = 0; i < SEG6_LOCAL_MAX + 1; i++) {
1021 if (slwt->desc->attrs & (1 << i)) {
1022 param = &seg6_action_params[i];
1023 err = param->put(skb, slwt);
1024 if (err < 0)
1025 return err;
1026 }
1027 }
1028
1029 return 0;
1030}
1031
1032static int seg6_local_get_encap_size(struct lwtunnel_state *lwt)
1033{
1034 struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
1035 unsigned long attrs;
1036 int nlsize;
1037
1038 nlsize = nla_total_size(4);
1039
1040 attrs = slwt->desc->attrs;
1041
1042 if (attrs & (1 << SEG6_LOCAL_SRH))
1043 nlsize += nla_total_size((slwt->srh->hdrlen + 1) << 3);
1044
1045 if (attrs & (1 << SEG6_LOCAL_TABLE))
1046 nlsize += nla_total_size(4);
1047
1048 if (attrs & (1 << SEG6_LOCAL_NH4))
1049 nlsize += nla_total_size(4);
1050
1051 if (attrs & (1 << SEG6_LOCAL_NH6))
1052 nlsize += nla_total_size(16);
1053
1054 if (attrs & (1 << SEG6_LOCAL_IIF))
1055 nlsize += nla_total_size(4);
1056
1057 if (attrs & (1 << SEG6_LOCAL_OIF))
1058 nlsize += nla_total_size(4);
1059
1060 if (attrs & (1 << SEG6_LOCAL_BPF))
1061 nlsize += nla_total_size(sizeof(struct nlattr)) +
1062 nla_total_size(MAX_PROG_NAME) +
1063 nla_total_size(4);
1064
1065 return nlsize;
1066}
1067
1068static int seg6_local_cmp_encap(struct lwtunnel_state *a,
1069 struct lwtunnel_state *b)
1070{
1071 struct seg6_local_lwt *slwt_a, *slwt_b;
1072 struct seg6_action_param *param;
1073 int i;
1074
1075 slwt_a = seg6_local_lwtunnel(a);
1076 slwt_b = seg6_local_lwtunnel(b);
1077
1078 if (slwt_a->action != slwt_b->action)
1079 return 1;
1080
1081 if (slwt_a->desc->attrs != slwt_b->desc->attrs)
1082 return 1;
1083
1084 for (i = 0; i < SEG6_LOCAL_MAX + 1; i++) {
1085 if (slwt_a->desc->attrs & (1 << i)) {
1086 param = &seg6_action_params[i];
1087 if (param->cmp(slwt_a, slwt_b))
1088 return 1;
1089 }
1090 }
1091
1092 return 0;
1093}
1094
1095static const struct lwtunnel_encap_ops seg6_local_ops = {
1096 .build_state = seg6_local_build_state,
1097 .destroy_state = seg6_local_destroy_state,
1098 .input = seg6_local_input,
1099 .fill_encap = seg6_local_fill_encap,
1100 .get_encap_size = seg6_local_get_encap_size,
1101 .cmp_encap = seg6_local_cmp_encap,
1102 .owner = THIS_MODULE,
1103};
1104
1105int __init seg6_local_init(void)
1106{
1107 return lwtunnel_encap_add_ops(&seg6_local_ops,
1108 LWTUNNEL_ENCAP_SEG6_LOCAL);
1109}
1110
1111void seg6_local_exit(void)
1112{
1113 lwtunnel_encap_del_ops(&seg6_local_ops, LWTUNNEL_ENCAP_SEG6_LOCAL);
1114}
1115
