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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * SR-IPv6 implementation
4 *
5 * Authors:
6 * David Lebrun <david.lebrun@uclouvain.be>
7 * eBPF support: Mathieu Xhonneux <m.xhonneux@gmail.com>
8 */
9
10#include <linux/filter.h>
11#include <linux/types.h>
12#include <linux/skbuff.h>
13#include <linux/net.h>
14#include <linux/module.h>
15#include <net/ip.h>
16#include <net/lwtunnel.h>
17#include <net/netevent.h>
18#include <net/netns/generic.h>
19#include <net/ip6_fib.h>
20#include <net/route.h>
21#include <net/seg6.h>
22#include <linux/seg6.h>
23#include <linux/seg6_local.h>
24#include <net/addrconf.h>
25#include <net/ip6_route.h>
26#include <net/dst_cache.h>
27#include <net/ip_tunnels.h>
28#ifdef CONFIG_IPV6_SEG6_HMAC
29#include <net/seg6_hmac.h>
30#endif
31#include <net/seg6_local.h>
32#include <linux/etherdevice.h>
33#include <linux/bpf.h>
34#include <linux/netfilter.h>
35
36#define SEG6_F_ATTR(i) BIT(i)
37
38struct seg6_local_lwt;
39
40/* callbacks used for customizing the creation and destruction of a behavior */
41struct seg6_local_lwtunnel_ops {
42 int (*build_state)(struct seg6_local_lwt *slwt, const void *cfg,
43 struct netlink_ext_ack *extack);
44 void (*destroy_state)(struct seg6_local_lwt *slwt);
45};
46
47struct seg6_action_desc {
48 int action;
49 unsigned long attrs;
50
51 /* The optattrs field is used for specifying all the optional
52 * attributes supported by a specific behavior.
53 * It means that if one of these attributes is not provided in the
54 * netlink message during the behavior creation, no errors will be
55 * returned to the userspace.
56 *
57 * Each attribute can be only of two types (mutually exclusive):
58 * 1) required or 2) optional.
59 * Every user MUST obey to this rule! If you set an attribute as
60 * required the same attribute CANNOT be set as optional and vice
61 * versa.
62 */
63 unsigned long optattrs;
64
65 int (*input)(struct sk_buff *skb, struct seg6_local_lwt *slwt);
66 int static_headroom;
67
68 struct seg6_local_lwtunnel_ops slwt_ops;
69};
70
71struct bpf_lwt_prog {
72 struct bpf_prog *prog;
73 char *name;
74};
75
76/* default length values (expressed in bits) for both Locator-Block and
77 * Locator-Node Function.
78 *
79 * Both SEG6_LOCAL_LCBLOCK_DBITS and SEG6_LOCAL_LCNODE_FN_DBITS *must* be:
80 * i) greater than 0;
81 * ii) evenly divisible by 8. In other terms, the lengths of the
82 * Locator-Block and Locator-Node Function must be byte-aligned (we can
83 * relax this constraint in the future if really needed).
84 *
85 * Moreover, a third condition must hold:
86 * iii) SEG6_LOCAL_LCBLOCK_DBITS + SEG6_LOCAL_LCNODE_FN_DBITS <= 128.
87 *
88 * The correctness of SEG6_LOCAL_LCBLOCK_DBITS and SEG6_LOCAL_LCNODE_FN_DBITS
89 * values are checked during the kernel compilation. If the compilation stops,
90 * check the value of these parameters to see if they meet conditions (i), (ii)
91 * and (iii).
92 */
93#define SEG6_LOCAL_LCBLOCK_DBITS 32
94#define SEG6_LOCAL_LCNODE_FN_DBITS 16
95
96/* The following next_csid_chk_{cntr,lcblock,lcblock_fn}_bits macros can be
97 * used directly to check whether the lengths (in bits) of Locator-Block and
98 * Locator-Node Function are valid according to (i), (ii), (iii).
99 */
100#define next_csid_chk_cntr_bits(blen, flen) \
101 ((blen) + (flen) > 128)
102
103#define next_csid_chk_lcblock_bits(blen) \
104({ \
105 typeof(blen) __tmp = blen; \
106 (!__tmp || __tmp > 120 || (__tmp & 0x07)); \
107})
108
109#define next_csid_chk_lcnode_fn_bits(flen) \
110 next_csid_chk_lcblock_bits(flen)
111
112/* flag indicating that flavors are set up for a given End* behavior */
113#define SEG6_F_LOCAL_FLAVORS SEG6_F_ATTR(SEG6_LOCAL_FLAVORS)
114
115#define SEG6_F_LOCAL_FLV_OP(flvname) BIT(SEG6_LOCAL_FLV_OP_##flvname)
116#define SEG6_F_LOCAL_FLV_NEXT_CSID SEG6_F_LOCAL_FLV_OP(NEXT_CSID)
117#define SEG6_F_LOCAL_FLV_PSP SEG6_F_LOCAL_FLV_OP(PSP)
118
119/* Supported RFC8986 Flavor operations are reported in this bitmask */
120#define SEG6_LOCAL_FLV8986_SUPP_OPS SEG6_F_LOCAL_FLV_PSP
121
122#define SEG6_LOCAL_END_FLV_SUPP_OPS (SEG6_F_LOCAL_FLV_NEXT_CSID | \
123 SEG6_LOCAL_FLV8986_SUPP_OPS)
124#define SEG6_LOCAL_END_X_FLV_SUPP_OPS SEG6_F_LOCAL_FLV_NEXT_CSID
125
126struct seg6_flavors_info {
127 /* Flavor operations */
128 __u32 flv_ops;
129
130 /* Locator-Block length, expressed in bits */
131 __u8 lcblock_bits;
132 /* Locator-Node Function length, expressed in bits*/
133 __u8 lcnode_func_bits;
134};
135
136enum seg6_end_dt_mode {
137 DT_INVALID_MODE = -EINVAL,
138 DT_LEGACY_MODE = 0,
139 DT_VRF_MODE = 1,
140};
141
142struct seg6_end_dt_info {
143 enum seg6_end_dt_mode mode;
144
145 struct net *net;
146 /* VRF device associated to the routing table used by the SRv6
147 * End.DT4/DT6 behavior for routing IPv4/IPv6 packets.
148 */
149 int vrf_ifindex;
150 int vrf_table;
151
152 /* tunneled packet family (IPv4 or IPv6).
153 * Protocol and header length are inferred from family.
154 */
155 u16 family;
156};
157
158struct pcpu_seg6_local_counters {
159 u64_stats_t packets;
160 u64_stats_t bytes;
161 u64_stats_t errors;
162
163 struct u64_stats_sync syncp;
164};
165
166/* This struct groups all the SRv6 Behavior counters supported so far.
167 *
168 * put_nla_counters() makes use of this data structure to collect all counter
169 * values after the per-CPU counter evaluation has been performed.
170 * Finally, each counter value (in seg6_local_counters) is stored in the
171 * corresponding netlink attribute and sent to user space.
172 *
173 * NB: we don't want to expose this structure to user space!
174 */
175struct seg6_local_counters {
176 __u64 packets;
177 __u64 bytes;
178 __u64 errors;
179};
180
181#define seg6_local_alloc_pcpu_counters(__gfp) \
182 __netdev_alloc_pcpu_stats(struct pcpu_seg6_local_counters, \
183 ((__gfp) | __GFP_ZERO))
184
185#define SEG6_F_LOCAL_COUNTERS SEG6_F_ATTR(SEG6_LOCAL_COUNTERS)
186
187struct seg6_local_lwt {
188 int action;
189 struct ipv6_sr_hdr *srh;
190 int table;
191 struct in_addr nh4;
192 struct in6_addr nh6;
193 int iif;
194 int oif;
195 struct bpf_lwt_prog bpf;
196#ifdef CONFIG_NET_L3_MASTER_DEV
197 struct seg6_end_dt_info dt_info;
198#endif
199 struct seg6_flavors_info flv_info;
200
201 struct pcpu_seg6_local_counters __percpu *pcpu_counters;
202
203 int headroom;
204 struct seg6_action_desc *desc;
205 /* unlike the required attrs, we have to track the optional attributes
206 * that have been effectively parsed.
207 */
208 unsigned long parsed_optattrs;
209};
210
211static struct seg6_local_lwt *seg6_local_lwtunnel(struct lwtunnel_state *lwt)
212{
213 return (struct seg6_local_lwt *)lwt->data;
214}
215
216static struct ipv6_sr_hdr *get_and_validate_srh(struct sk_buff *skb)
217{
218 struct ipv6_sr_hdr *srh;
219
220 srh = seg6_get_srh(skb, IP6_FH_F_SKIP_RH);
221 if (!srh)
222 return NULL;
223
224#ifdef CONFIG_IPV6_SEG6_HMAC
225 if (!seg6_hmac_validate_skb(skb))
226 return NULL;
227#endif
228
229 return srh;
230}
231
232static bool decap_and_validate(struct sk_buff *skb, int proto)
233{
234 struct ipv6_sr_hdr *srh;
235 unsigned int off = 0;
236
237 srh = seg6_get_srh(skb, 0);
238 if (srh && srh->segments_left > 0)
239 return false;
240
241#ifdef CONFIG_IPV6_SEG6_HMAC
242 if (srh && !seg6_hmac_validate_skb(skb))
243 return false;
244#endif
245
246 if (ipv6_find_hdr(skb, &off, proto, NULL, NULL) < 0)
247 return false;
248
249 if (!pskb_pull(skb, off))
250 return false;
251
252 skb_postpull_rcsum(skb, skb_network_header(skb), off);
253
254 skb_reset_network_header(skb);
255 skb_reset_transport_header(skb);
256 if (iptunnel_pull_offloads(skb))
257 return false;
258
259 return true;
260}
261
262static void advance_nextseg(struct ipv6_sr_hdr *srh, struct in6_addr *daddr)
263{
264 struct in6_addr *addr;
265
266 srh->segments_left--;
267 addr = srh->segments + srh->segments_left;
268 *daddr = *addr;
269}
270
271static int
272seg6_lookup_any_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
273 u32 tbl_id, bool local_delivery)
274{
275 struct net *net = dev_net(skb->dev);
276 struct ipv6hdr *hdr = ipv6_hdr(skb);
277 int flags = RT6_LOOKUP_F_HAS_SADDR;
278 struct dst_entry *dst = NULL;
279 struct rt6_info *rt;
280 struct flowi6 fl6;
281 int dev_flags = 0;
282
283 memset(&fl6, 0, sizeof(fl6));
284 fl6.flowi6_iif = skb->dev->ifindex;
285 fl6.daddr = nhaddr ? *nhaddr : hdr->daddr;
286 fl6.saddr = hdr->saddr;
287 fl6.flowlabel = ip6_flowinfo(hdr);
288 fl6.flowi6_mark = skb->mark;
289 fl6.flowi6_proto = hdr->nexthdr;
290
291 if (nhaddr)
292 fl6.flowi6_flags = FLOWI_FLAG_KNOWN_NH;
293
294 if (!tbl_id) {
295 dst = ip6_route_input_lookup(net, skb->dev, &fl6, skb, flags);
296 } else {
297 struct fib6_table *table;
298
299 table = fib6_get_table(net, tbl_id);
300 if (!table)
301 goto out;
302
303 rt = ip6_pol_route(net, table, 0, &fl6, skb, flags);
304 dst = &rt->dst;
305 }
306
307 /* we want to discard traffic destined for local packet processing,
308 * if @local_delivery is set to false.
309 */
310 if (!local_delivery)
311 dev_flags |= IFF_LOOPBACK;
312
313 if (dst && (dst->dev->flags & dev_flags) && !dst->error) {
314 dst_release(dst);
315 dst = NULL;
316 }
317
318out:
319 if (!dst) {
320 rt = net->ipv6.ip6_blk_hole_entry;
321 dst = &rt->dst;
322 dst_hold(dst);
323 }
324
325 skb_dst_drop(skb);
326 skb_dst_set(skb, dst);
327 return dst->error;
328}
329
330int seg6_lookup_nexthop(struct sk_buff *skb,
331 struct in6_addr *nhaddr, u32 tbl_id)
332{
333 return seg6_lookup_any_nexthop(skb, nhaddr, tbl_id, false);
334}
335
336static __u8 seg6_flv_lcblock_octects(const struct seg6_flavors_info *finfo)
337{
338 return finfo->lcblock_bits >> 3;
339}
340
341static __u8 seg6_flv_lcnode_func_octects(const struct seg6_flavors_info *finfo)
342{
343 return finfo->lcnode_func_bits >> 3;
344}
345
346static bool seg6_next_csid_is_arg_zero(const struct in6_addr *addr,
347 const struct seg6_flavors_info *finfo)
348{
349 __u8 fnc_octects = seg6_flv_lcnode_func_octects(finfo);
350 __u8 blk_octects = seg6_flv_lcblock_octects(finfo);
351 __u8 arg_octects;
352 int i;
353
354 arg_octects = 16 - blk_octects - fnc_octects;
355 for (i = 0; i < arg_octects; ++i) {
356 if (addr->s6_addr[blk_octects + fnc_octects + i] != 0x00)
357 return false;
358 }
359
360 return true;
361}
362
363/* assume that DA.Argument length > 0 */
364static void seg6_next_csid_advance_arg(struct in6_addr *addr,
365 const struct seg6_flavors_info *finfo)
366{
367 __u8 fnc_octects = seg6_flv_lcnode_func_octects(finfo);
368 __u8 blk_octects = seg6_flv_lcblock_octects(finfo);
369
370 /* advance DA.Argument */
371 memmove(&addr->s6_addr[blk_octects],
372 &addr->s6_addr[blk_octects + fnc_octects],
373 16 - blk_octects - fnc_octects);
374
375 memset(&addr->s6_addr[16 - fnc_octects], 0x00, fnc_octects);
376}
377
378static int input_action_end_finish(struct sk_buff *skb,
379 struct seg6_local_lwt *slwt)
380{
381 seg6_lookup_nexthop(skb, NULL, 0);
382
383 return dst_input(skb);
384}
385
386static int input_action_end_core(struct sk_buff *skb,
387 struct seg6_local_lwt *slwt)
388{
389 struct ipv6_sr_hdr *srh;
390
391 srh = get_and_validate_srh(skb);
392 if (!srh)
393 goto drop;
394
395 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
396
397 return input_action_end_finish(skb, slwt);
398
399drop:
400 kfree_skb(skb);
401 return -EINVAL;
402}
403
404static int end_next_csid_core(struct sk_buff *skb, struct seg6_local_lwt *slwt)
405{
406 const struct seg6_flavors_info *finfo = &slwt->flv_info;
407 struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
408
409 if (seg6_next_csid_is_arg_zero(daddr, finfo))
410 return input_action_end_core(skb, slwt);
411
412 /* update DA */
413 seg6_next_csid_advance_arg(daddr, finfo);
414
415 return input_action_end_finish(skb, slwt);
416}
417
418static int input_action_end_x_finish(struct sk_buff *skb,
419 struct seg6_local_lwt *slwt)
420{
421 seg6_lookup_nexthop(skb, &slwt->nh6, 0);
422
423 return dst_input(skb);
424}
425
426static int input_action_end_x_core(struct sk_buff *skb,
427 struct seg6_local_lwt *slwt)
428{
429 struct ipv6_sr_hdr *srh;
430
431 srh = get_and_validate_srh(skb);
432 if (!srh)
433 goto drop;
434
435 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
436
437 return input_action_end_x_finish(skb, slwt);
438
439drop:
440 kfree_skb(skb);
441 return -EINVAL;
442}
443
444static int end_x_next_csid_core(struct sk_buff *skb,
445 struct seg6_local_lwt *slwt)
446{
447 const struct seg6_flavors_info *finfo = &slwt->flv_info;
448 struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
449
450 if (seg6_next_csid_is_arg_zero(daddr, finfo))
451 return input_action_end_x_core(skb, slwt);
452
453 /* update DA */
454 seg6_next_csid_advance_arg(daddr, finfo);
455
456 return input_action_end_x_finish(skb, slwt);
457}
458
459static bool seg6_next_csid_enabled(__u32 fops)
460{
461 return fops & SEG6_F_LOCAL_FLV_NEXT_CSID;
462}
463
464/* Processing of SRv6 End, End.X, and End.T behaviors can be extended through
465 * the flavors framework. These behaviors must report the subset of (flavor)
466 * operations they currently implement. In this way, if a user specifies a
467 * flavor combination that is not supported by a given End* behavior, the
468 * kernel refuses to instantiate the tunnel reporting the error.
469 */
470static int seg6_flv_supp_ops_by_action(int action, __u32 *fops)
471{
472 switch (action) {
473 case SEG6_LOCAL_ACTION_END:
474 *fops = SEG6_LOCAL_END_FLV_SUPP_OPS;
475 break;
476 case SEG6_LOCAL_ACTION_END_X:
477 *fops = SEG6_LOCAL_END_X_FLV_SUPP_OPS;
478 break;
479 default:
480 return -EOPNOTSUPP;
481 }
482
483 return 0;
484}
485
486/* We describe the packet state in relation to the absence/presence of the SRH
487 * and the Segment Left (SL) field.
488 * For our purposes, it is not necessary to record the exact value of the SL
489 * when the SID List consists of two or more segments.
490 */
491enum seg6_local_pktinfo {
492 /* the order really matters! */
493 SEG6_LOCAL_PKTINFO_NOHDR = 0,
494 SEG6_LOCAL_PKTINFO_SL_ZERO,
495 SEG6_LOCAL_PKTINFO_SL_ONE,
496 SEG6_LOCAL_PKTINFO_SL_MORE,
497 __SEG6_LOCAL_PKTINFO_MAX,
498};
499
500#define SEG6_LOCAL_PKTINFO_MAX (__SEG6_LOCAL_PKTINFO_MAX - 1)
501
502static enum seg6_local_pktinfo seg6_get_srh_pktinfo(struct ipv6_sr_hdr *srh)
503{
504 __u8 sgl;
505
506 if (!srh)
507 return SEG6_LOCAL_PKTINFO_NOHDR;
508
509 sgl = srh->segments_left;
510 if (sgl < 2)
511 return SEG6_LOCAL_PKTINFO_SL_ZERO + sgl;
512
513 return SEG6_LOCAL_PKTINFO_SL_MORE;
514}
515
516enum seg6_local_flv_action {
517 SEG6_LOCAL_FLV_ACT_UNSPEC = 0,
518 SEG6_LOCAL_FLV_ACT_END,
519 SEG6_LOCAL_FLV_ACT_PSP,
520 SEG6_LOCAL_FLV_ACT_USP,
521 SEG6_LOCAL_FLV_ACT_USD,
522 __SEG6_LOCAL_FLV_ACT_MAX
523};
524
525#define SEG6_LOCAL_FLV_ACT_MAX (__SEG6_LOCAL_FLV_ACT_MAX - 1)
526
527/* The action table for RFC8986 flavors (see the flv8986_act_tbl below)
528 * contains the actions (i.e. processing operations) to be applied on packets
529 * when flavors are configured for an End* behavior.
530 * By combining the pkinfo data and from the flavors mask, the macro
531 * computes the index used to access the elements (actions) stored in the
532 * action table. The index is structured as follows:
533 *
534 * index
535 * _______________/\________________
536 * / \
537 * +----------------+----------------+
538 * | pf | afm |
539 * +----------------+----------------+
540 * ph-1 ... p1 p0 fk-1 ... f1 f0
541 * MSB LSB
542 *
543 * where:
544 * - 'afm' (adjusted flavor mask) is the mask containing a combination of the
545 * RFC8986 flavors currently supported. 'afm' corresponds to the @fm
546 * argument of the macro whose value is righ-shifted by 1 bit. By doing so,
547 * we discard the SEG6_LOCAL_FLV_OP_UNSPEC flag (bit 0 in @fm) which is
548 * never used here;
549 * - 'pf' encodes the packet info (pktinfo) regarding the presence/absence of
550 * the SRH, SL = 0, etc. 'pf' is set with the value of @pf provided as
551 * argument to the macro.
552 */
553#define flv8986_act_tbl_idx(pf, fm) \
554 ((((pf) << bits_per(SEG6_LOCAL_FLV8986_SUPP_OPS)) | \
555 ((fm) & SEG6_LOCAL_FLV8986_SUPP_OPS)) >> SEG6_LOCAL_FLV_OP_PSP)
556
557/* We compute the size of the action table by considering the RFC8986 flavors
558 * actually supported by the kernel. In this way, the size is automatically
559 * adjusted when new flavors are supported.
560 */
561#define FLV8986_ACT_TBL_SIZE \
562 roundup_pow_of_two(flv8986_act_tbl_idx(SEG6_LOCAL_PKTINFO_MAX, \
563 SEG6_LOCAL_FLV8986_SUPP_OPS))
564
565/* tbl_cfg(act, pf, fm) macro is used to easily configure the action
566 * table; it accepts 3 arguments:
567 * i) @act, the suffix from SEG6_LOCAL_FLV_ACT_{act} representing
568 * the action that should be applied on the packet;
569 * ii) @pf, the suffix from SEG6_LOCAL_PKTINFO_{pf} reporting the packet
570 * info about the lack/presence of SRH, SRH with SL = 0, etc;
571 * iii) @fm, the mask of flavors.
572 */
573#define tbl_cfg(act, pf, fm) \
574 [flv8986_act_tbl_idx(SEG6_LOCAL_PKTINFO_##pf, \
575 (fm))] = SEG6_LOCAL_FLV_ACT_##act
576
577/* shorthand for improving readability */
578#define F_PSP SEG6_F_LOCAL_FLV_PSP
579
580/* The table contains, for each combination of the pktinfo data and
581 * flavors, the action that should be taken on a packet (e.g.
582 * "standard" Endpoint processing, Penultimate Segment Pop, etc).
583 *
584 * By default, table entries not explicitly configured are initialized with the
585 * SEG6_LOCAL_FLV_ACT_UNSPEC action, which generally has the effect of
586 * discarding the processed packet.
587 */
588static const u8 flv8986_act_tbl[FLV8986_ACT_TBL_SIZE] = {
589 /* PSP variant for packet where SRH with SL = 1 */
590 tbl_cfg(PSP, SL_ONE, F_PSP),
591 /* End for packet where the SRH with SL > 1*/
592 tbl_cfg(END, SL_MORE, F_PSP),
593};
594
595#undef F_PSP
596#undef tbl_cfg
597
598/* For each flavor defined in RFC8986 (or a combination of them) an action is
599 * performed on the packet. The specific action depends on:
600 * - info extracted from the packet (i.e. pktinfo data) regarding the
601 * lack/presence of the SRH, and if the SRH is available, on the value of
602 * Segment Left field;
603 * - the mask of flavors configured for the specific SRv6 End* behavior.
604 *
605 * The function combines both the pkinfo and the flavors mask to evaluate the
606 * corresponding action to be taken on the packet.
607 */
608static enum seg6_local_flv_action
609seg6_local_flv8986_act_lookup(enum seg6_local_pktinfo pinfo, __u32 flvmask)
610{
611 unsigned long index;
612
613 /* check if the provided mask of flavors is supported */
614 if (unlikely(flvmask & ~SEG6_LOCAL_FLV8986_SUPP_OPS))
615 return SEG6_LOCAL_FLV_ACT_UNSPEC;
616
617 index = flv8986_act_tbl_idx(pinfo, flvmask);
618 if (unlikely(index >= FLV8986_ACT_TBL_SIZE))
619 return SEG6_LOCAL_FLV_ACT_UNSPEC;
620
621 return flv8986_act_tbl[index];
622}
623
624/* skb->data must be aligned with skb->network_header */
625static bool seg6_pop_srh(struct sk_buff *skb, int srhoff)
626{
627 struct ipv6_sr_hdr *srh;
628 struct ipv6hdr *iph;
629 __u8 srh_nexthdr;
630 int thoff = -1;
631 int srhlen;
632 int nhlen;
633
634 if (unlikely(srhoff < sizeof(*iph) ||
635 !pskb_may_pull(skb, srhoff + sizeof(*srh))))
636 return false;
637
638 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
639 srhlen = ipv6_optlen(srh);
640
641 /* we are about to mangle the pkt, let's check if we can write on it */
642 if (unlikely(skb_ensure_writable(skb, srhoff + srhlen)))
643 return false;
644
645 /* skb_ensure_writable() may change skb pointers; evaluate srh again */
646 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
647 srh_nexthdr = srh->nexthdr;
648
649 if (unlikely(!skb_transport_header_was_set(skb)))
650 goto pull;
651
652 nhlen = skb_network_header_len(skb);
653 /* we have to deal with the transport header: it could be set before
654 * the SRH, after the SRH, or within it (which is considered wrong,
655 * however).
656 */
657 if (likely(nhlen <= srhoff))
658 thoff = nhlen;
659 else if (nhlen >= srhoff + srhlen)
660 /* transport_header is set after the SRH */
661 thoff = nhlen - srhlen;
662 else
663 /* transport_header falls inside the SRH; hence, we can't
664 * restore the transport_header pointer properly after
665 * SRH removing operation.
666 */
667 return false;
668pull:
669 /* we need to pop the SRH:
670 * 1) first of all, we pull out everything from IPv6 header up to SRH
671 * (included) evaluating also the rcsum;
672 * 2) we overwrite (and then remove) the SRH by properly moving the
673 * IPv6 along with any extension header that precedes the SRH;
674 * 3) At the end, we push back the pulled headers (except for SRH,
675 * obviously).
676 */
677 skb_pull_rcsum(skb, srhoff + srhlen);
678 memmove(skb_network_header(skb) + srhlen, skb_network_header(skb),
679 srhoff);
680 skb_push(skb, srhoff);
681
682 skb_reset_network_header(skb);
683 skb_mac_header_rebuild(skb);
684 if (likely(thoff >= 0))
685 skb_set_transport_header(skb, thoff);
686
687 iph = ipv6_hdr(skb);
688 if (iph->nexthdr == NEXTHDR_ROUTING) {
689 iph->nexthdr = srh_nexthdr;
690 } else {
691 /* we must look for the extension header (EXTH, for short) that
692 * immediately precedes the SRH we have just removed.
693 * Then, we update the value of the EXTH nexthdr with the one
694 * contained in the SRH nexthdr.
695 */
696 unsigned int off = sizeof(*iph);
697 struct ipv6_opt_hdr *hp, _hdr;
698 __u8 nexthdr = iph->nexthdr;
699
700 for (;;) {
701 if (unlikely(!ipv6_ext_hdr(nexthdr) ||
702 nexthdr == NEXTHDR_NONE))
703 return false;
704
705 hp = skb_header_pointer(skb, off, sizeof(_hdr), &_hdr);
706 if (unlikely(!hp))
707 return false;
708
709 if (hp->nexthdr == NEXTHDR_ROUTING) {
710 hp->nexthdr = srh_nexthdr;
711 break;
712 }
713
714 switch (nexthdr) {
715 case NEXTHDR_FRAGMENT:
716 fallthrough;
717 case NEXTHDR_AUTH:
718 /* we expect SRH before FRAG and AUTH */
719 return false;
720 default:
721 off += ipv6_optlen(hp);
722 break;
723 }
724
725 nexthdr = hp->nexthdr;
726 }
727 }
728
729 iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
730
731 skb_postpush_rcsum(skb, iph, srhoff);
732
733 return true;
734}
735
736/* process the packet on the basis of the RFC8986 flavors set for the given
737 * SRv6 End behavior instance.
738 */
739static int end_flv8986_core(struct sk_buff *skb, struct seg6_local_lwt *slwt)
740{
741 const struct seg6_flavors_info *finfo = &slwt->flv_info;
742 enum seg6_local_flv_action action;
743 enum seg6_local_pktinfo pinfo;
744 struct ipv6_sr_hdr *srh;
745 __u32 flvmask;
746 int srhoff;
747
748 srh = seg6_get_srh(skb, 0);
749 srhoff = srh ? ((unsigned char *)srh - skb->data) : 0;
750 pinfo = seg6_get_srh_pktinfo(srh);
751#ifdef CONFIG_IPV6_SEG6_HMAC
752 if (srh && !seg6_hmac_validate_skb(skb))
753 goto drop;
754#endif
755 flvmask = finfo->flv_ops;
756 if (unlikely(flvmask & ~SEG6_LOCAL_FLV8986_SUPP_OPS)) {
757 pr_warn_once("seg6local: invalid RFC8986 flavors\n");
758 goto drop;
759 }
760
761 /* retrieve the action triggered by the combination of pktinfo data and
762 * the flavors mask.
763 */
764 action = seg6_local_flv8986_act_lookup(pinfo, flvmask);
765 switch (action) {
766 case SEG6_LOCAL_FLV_ACT_END:
767 /* process the packet as the "standard" End behavior */
768 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
769 break;
770 case SEG6_LOCAL_FLV_ACT_PSP:
771 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
772
773 if (unlikely(!seg6_pop_srh(skb, srhoff)))
774 goto drop;
775 break;
776 case SEG6_LOCAL_FLV_ACT_UNSPEC:
777 fallthrough;
778 default:
779 /* by default, we drop the packet since we could not find a
780 * suitable action.
781 */
782 goto drop;
783 }
784
785 return input_action_end_finish(skb, slwt);
786
787drop:
788 kfree_skb(skb);
789 return -EINVAL;
790}
791
792/* regular endpoint function */
793static int input_action_end(struct sk_buff *skb, struct seg6_local_lwt *slwt)
794{
795 const struct seg6_flavors_info *finfo = &slwt->flv_info;
796 __u32 fops = finfo->flv_ops;
797
798 if (!fops)
799 return input_action_end_core(skb, slwt);
800
801 /* check for the presence of NEXT-C-SID since it applies first */
802 if (seg6_next_csid_enabled(fops))
803 return end_next_csid_core(skb, slwt);
804
805 /* the specific processing function to be performed on the packet
806 * depends on the combination of flavors defined in RFC8986 and some
807 * information extracted from the packet, e.g. presence/absence of SRH,
808 * Segment Left = 0, etc.
809 */
810 return end_flv8986_core(skb, slwt);
811}
812
813/* regular endpoint, and forward to specified nexthop */
814static int input_action_end_x(struct sk_buff *skb, struct seg6_local_lwt *slwt)
815{
816 const struct seg6_flavors_info *finfo = &slwt->flv_info;
817 __u32 fops = finfo->flv_ops;
818
819 /* check for the presence of NEXT-C-SID since it applies first */
820 if (seg6_next_csid_enabled(fops))
821 return end_x_next_csid_core(skb, slwt);
822
823 return input_action_end_x_core(skb, slwt);
824}
825
826static int input_action_end_t(struct sk_buff *skb, struct seg6_local_lwt *slwt)
827{
828 struct ipv6_sr_hdr *srh;
829
830 srh = get_and_validate_srh(skb);
831 if (!srh)
832 goto drop;
833
834 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
835
836 seg6_lookup_nexthop(skb, NULL, slwt->table);
837
838 return dst_input(skb);
839
840drop:
841 kfree_skb(skb);
842 return -EINVAL;
843}
844
845/* decapsulate and forward inner L2 frame on specified interface */
846static int input_action_end_dx2(struct sk_buff *skb,
847 struct seg6_local_lwt *slwt)
848{
849 struct net *net = dev_net(skb->dev);
850 struct net_device *odev;
851 struct ethhdr *eth;
852
853 if (!decap_and_validate(skb, IPPROTO_ETHERNET))
854 goto drop;
855
856 if (!pskb_may_pull(skb, ETH_HLEN))
857 goto drop;
858
859 skb_reset_mac_header(skb);
860 eth = (struct ethhdr *)skb->data;
861
862 /* To determine the frame's protocol, we assume it is 802.3. This avoids
863 * a call to eth_type_trans(), which is not really relevant for our
864 * use case.
865 */
866 if (!eth_proto_is_802_3(eth->h_proto))
867 goto drop;
868
869 odev = dev_get_by_index_rcu(net, slwt->oif);
870 if (!odev)
871 goto drop;
872
873 /* As we accept Ethernet frames, make sure the egress device is of
874 * the correct type.
875 */
876 if (odev->type != ARPHRD_ETHER)
877 goto drop;
878
879 if (!(odev->flags & IFF_UP) || !netif_carrier_ok(odev))
880 goto drop;
881
882 skb_orphan(skb);
883
884 if (skb_warn_if_lro(skb))
885 goto drop;
886
887 skb_forward_csum(skb);
888
889 if (skb->len - ETH_HLEN > odev->mtu)
890 goto drop;
891
892 skb->dev = odev;
893 skb->protocol = eth->h_proto;
894
895 return dev_queue_xmit(skb);
896
897drop:
898 kfree_skb(skb);
899 return -EINVAL;
900}
901
902static int input_action_end_dx6_finish(struct net *net, struct sock *sk,
903 struct sk_buff *skb)
904{
905 struct dst_entry *orig_dst = skb_dst(skb);
906 struct in6_addr *nhaddr = NULL;
907 struct seg6_local_lwt *slwt;
908
909 slwt = seg6_local_lwtunnel(orig_dst->lwtstate);
910
911 /* The inner packet is not associated to any local interface,
912 * so we do not call netif_rx().
913 *
914 * If slwt->nh6 is set to ::, then lookup the nexthop for the
915 * inner packet's DA. Otherwise, use the specified nexthop.
916 */
917 if (!ipv6_addr_any(&slwt->nh6))
918 nhaddr = &slwt->nh6;
919
920 seg6_lookup_nexthop(skb, nhaddr, 0);
921
922 return dst_input(skb);
923}
924
925/* decapsulate and forward to specified nexthop */
926static int input_action_end_dx6(struct sk_buff *skb,
927 struct seg6_local_lwt *slwt)
928{
929 /* this function accepts IPv6 encapsulated packets, with either
930 * an SRH with SL=0, or no SRH.
931 */
932
933 if (!decap_and_validate(skb, IPPROTO_IPV6))
934 goto drop;
935
936 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
937 goto drop;
938
939 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
940 nf_reset_ct(skb);
941
942 if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
943 return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
944 dev_net(skb->dev), NULL, skb, NULL,
945 skb_dst(skb)->dev, input_action_end_dx6_finish);
946
947 return input_action_end_dx6_finish(dev_net(skb->dev), NULL, skb);
948drop:
949 kfree_skb(skb);
950 return -EINVAL;
951}
952
953static int input_action_end_dx4_finish(struct net *net, struct sock *sk,
954 struct sk_buff *skb)
955{
956 struct dst_entry *orig_dst = skb_dst(skb);
957 struct seg6_local_lwt *slwt;
958 struct iphdr *iph;
959 __be32 nhaddr;
960 int err;
961
962 slwt = seg6_local_lwtunnel(orig_dst->lwtstate);
963
964 iph = ip_hdr(skb);
965
966 nhaddr = slwt->nh4.s_addr ?: iph->daddr;
967
968 skb_dst_drop(skb);
969
970 err = ip_route_input(skb, nhaddr, iph->saddr, 0, skb->dev);
971 if (err) {
972 kfree_skb(skb);
973 return -EINVAL;
974 }
975
976 return dst_input(skb);
977}
978
979static int input_action_end_dx4(struct sk_buff *skb,
980 struct seg6_local_lwt *slwt)
981{
982 if (!decap_and_validate(skb, IPPROTO_IPIP))
983 goto drop;
984
985 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
986 goto drop;
987
988 skb->protocol = htons(ETH_P_IP);
989 skb_set_transport_header(skb, sizeof(struct iphdr));
990 nf_reset_ct(skb);
991
992 if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
993 return NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING,
994 dev_net(skb->dev), NULL, skb, NULL,
995 skb_dst(skb)->dev, input_action_end_dx4_finish);
996
997 return input_action_end_dx4_finish(dev_net(skb->dev), NULL, skb);
998drop:
999 kfree_skb(skb);
1000 return -EINVAL;
1001}
1002
1003#ifdef CONFIG_NET_L3_MASTER_DEV
1004static struct net *fib6_config_get_net(const struct fib6_config *fib6_cfg)
1005{
1006 const struct nl_info *nli = &fib6_cfg->fc_nlinfo;
1007
1008 return nli->nl_net;
1009}
1010
1011static int __seg6_end_dt_vrf_build(struct seg6_local_lwt *slwt, const void *cfg,
1012 u16 family, struct netlink_ext_ack *extack)
1013{
1014 struct seg6_end_dt_info *info = &slwt->dt_info;
1015 int vrf_ifindex;
1016 struct net *net;
1017
1018 net = fib6_config_get_net(cfg);
1019
1020 /* note that vrf_table was already set by parse_nla_vrftable() */
1021 vrf_ifindex = l3mdev_ifindex_lookup_by_table_id(L3MDEV_TYPE_VRF, net,
1022 info->vrf_table);
1023 if (vrf_ifindex < 0) {
1024 if (vrf_ifindex == -EPERM) {
1025 NL_SET_ERR_MSG(extack,
1026 "Strict mode for VRF is disabled");
1027 } else if (vrf_ifindex == -ENODEV) {
1028 NL_SET_ERR_MSG(extack,
1029 "Table has no associated VRF device");
1030 } else {
1031 pr_debug("seg6local: SRv6 End.DT* creation error=%d\n",
1032 vrf_ifindex);
1033 }
1034
1035 return vrf_ifindex;
1036 }
1037
1038 info->net = net;
1039 info->vrf_ifindex = vrf_ifindex;
1040
1041 info->family = family;
1042 info->mode = DT_VRF_MODE;
1043
1044 return 0;
1045}
1046
1047/* The SRv6 End.DT4/DT6 behavior extracts the inner (IPv4/IPv6) packet and
1048 * routes the IPv4/IPv6 packet by looking at the configured routing table.
1049 *
1050 * In the SRv6 End.DT4/DT6 use case, we can receive traffic (IPv6+Segment
1051 * Routing Header packets) from several interfaces and the outer IPv6
1052 * destination address (DA) is used for retrieving the specific instance of the
1053 * End.DT4/DT6 behavior that should process the packets.
1054 *
1055 * However, the inner IPv4/IPv6 packet is not really bound to any receiving
1056 * interface and thus the End.DT4/DT6 sets the VRF (associated with the
1057 * corresponding routing table) as the *receiving* interface.
1058 * In other words, the End.DT4/DT6 processes a packet as if it has been received
1059 * directly by the VRF (and not by one of its slave devices, if any).
1060 * In this way, the VRF interface is used for routing the IPv4/IPv6 packet in
1061 * according to the routing table configured by the End.DT4/DT6 instance.
1062 *
1063 * This design allows you to get some interesting features like:
1064 * 1) the statistics on rx packets;
1065 * 2) the possibility to install a packet sniffer on the receiving interface
1066 * (the VRF one) for looking at the incoming packets;
1067 * 3) the possibility to leverage the netfilter prerouting hook for the inner
1068 * IPv4 packet.
1069 *
1070 * This function returns:
1071 * - the sk_buff* when the VRF rcv handler has processed the packet correctly;
1072 * - NULL when the skb is consumed by the VRF rcv handler;
1073 * - a pointer which encodes a negative error number in case of error.
1074 * Note that in this case, the function takes care of freeing the skb.
1075 */
1076static struct sk_buff *end_dt_vrf_rcv(struct sk_buff *skb, u16 family,
1077 struct net_device *dev)
1078{
1079 /* based on l3mdev_ip_rcv; we are only interested in the master */
1080 if (unlikely(!netif_is_l3_master(dev) && !netif_has_l3_rx_handler(dev)))
1081 goto drop;
1082
1083 if (unlikely(!dev->l3mdev_ops->l3mdev_l3_rcv))
1084 goto drop;
1085
1086 /* the decap packet IPv4/IPv6 does not come with any mac header info.
1087 * We must unset the mac header to allow the VRF device to rebuild it,
1088 * just in case there is a sniffer attached on the device.
1089 */
1090 skb_unset_mac_header(skb);
1091
1092 skb = dev->l3mdev_ops->l3mdev_l3_rcv(dev, skb, family);
1093 if (!skb)
1094 /* the skb buffer was consumed by the handler */
1095 return NULL;
1096
1097 /* when a packet is received by a VRF or by one of its slaves, the
1098 * master device reference is set into the skb.
1099 */
1100 if (unlikely(skb->dev != dev || skb->skb_iif != dev->ifindex))
1101 goto drop;
1102
1103 return skb;
1104
1105drop:
1106 kfree_skb(skb);
1107 return ERR_PTR(-EINVAL);
1108}
1109
1110static struct net_device *end_dt_get_vrf_rcu(struct sk_buff *skb,
1111 struct seg6_end_dt_info *info)
1112{
1113 int vrf_ifindex = info->vrf_ifindex;
1114 struct net *net = info->net;
1115
1116 if (unlikely(vrf_ifindex < 0))
1117 goto error;
1118
1119 if (unlikely(!net_eq(dev_net(skb->dev), net)))
1120 goto error;
1121
1122 return dev_get_by_index_rcu(net, vrf_ifindex);
1123
1124error:
1125 return NULL;
1126}
1127
1128static struct sk_buff *end_dt_vrf_core(struct sk_buff *skb,
1129 struct seg6_local_lwt *slwt, u16 family)
1130{
1131 struct seg6_end_dt_info *info = &slwt->dt_info;
1132 struct net_device *vrf;
1133 __be16 protocol;
1134 int hdrlen;
1135
1136 vrf = end_dt_get_vrf_rcu(skb, info);
1137 if (unlikely(!vrf))
1138 goto drop;
1139
1140 switch (family) {
1141 case AF_INET:
1142 protocol = htons(ETH_P_IP);
1143 hdrlen = sizeof(struct iphdr);
1144 break;
1145 case AF_INET6:
1146 protocol = htons(ETH_P_IPV6);
1147 hdrlen = sizeof(struct ipv6hdr);
1148 break;
1149 case AF_UNSPEC:
1150 fallthrough;
1151 default:
1152 goto drop;
1153 }
1154
1155 if (unlikely(info->family != AF_UNSPEC && info->family != family)) {
1156 pr_warn_once("seg6local: SRv6 End.DT* family mismatch");
1157 goto drop;
1158 }
1159
1160 skb->protocol = protocol;
1161
1162 skb_dst_drop(skb);
1163
1164 skb_set_transport_header(skb, hdrlen);
1165 nf_reset_ct(skb);
1166
1167 return end_dt_vrf_rcv(skb, family, vrf);
1168
1169drop:
1170 kfree_skb(skb);
1171 return ERR_PTR(-EINVAL);
1172}
1173
1174static int input_action_end_dt4(struct sk_buff *skb,
1175 struct seg6_local_lwt *slwt)
1176{
1177 struct iphdr *iph;
1178 int err;
1179
1180 if (!decap_and_validate(skb, IPPROTO_IPIP))
1181 goto drop;
1182
1183 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
1184 goto drop;
1185
1186 skb = end_dt_vrf_core(skb, slwt, AF_INET);
1187 if (!skb)
1188 /* packet has been processed and consumed by the VRF */
1189 return 0;
1190
1191 if (IS_ERR(skb))
1192 return PTR_ERR(skb);
1193
1194 iph = ip_hdr(skb);
1195
1196 err = ip_route_input(skb, iph->daddr, iph->saddr, 0, skb->dev);
1197 if (unlikely(err))
1198 goto drop;
1199
1200 return dst_input(skb);
1201
1202drop:
1203 kfree_skb(skb);
1204 return -EINVAL;
1205}
1206
1207static int seg6_end_dt4_build(struct seg6_local_lwt *slwt, const void *cfg,
1208 struct netlink_ext_ack *extack)
1209{
1210 return __seg6_end_dt_vrf_build(slwt, cfg, AF_INET, extack);
1211}
1212
1213static enum
1214seg6_end_dt_mode seg6_end_dt6_parse_mode(struct seg6_local_lwt *slwt)
1215{
1216 unsigned long parsed_optattrs = slwt->parsed_optattrs;
1217 bool legacy, vrfmode;
1218
1219 legacy = !!(parsed_optattrs & SEG6_F_ATTR(SEG6_LOCAL_TABLE));
1220 vrfmode = !!(parsed_optattrs & SEG6_F_ATTR(SEG6_LOCAL_VRFTABLE));
1221
1222 if (!(legacy ^ vrfmode))
1223 /* both are absent or present: invalid DT6 mode */
1224 return DT_INVALID_MODE;
1225
1226 return legacy ? DT_LEGACY_MODE : DT_VRF_MODE;
1227}
1228
1229static enum seg6_end_dt_mode seg6_end_dt6_get_mode(struct seg6_local_lwt *slwt)
1230{
1231 struct seg6_end_dt_info *info = &slwt->dt_info;
1232
1233 return info->mode;
1234}
1235
1236static int seg6_end_dt6_build(struct seg6_local_lwt *slwt, const void *cfg,
1237 struct netlink_ext_ack *extack)
1238{
1239 enum seg6_end_dt_mode mode = seg6_end_dt6_parse_mode(slwt);
1240 struct seg6_end_dt_info *info = &slwt->dt_info;
1241
1242 switch (mode) {
1243 case DT_LEGACY_MODE:
1244 info->mode = DT_LEGACY_MODE;
1245 return 0;
1246 case DT_VRF_MODE:
1247 return __seg6_end_dt_vrf_build(slwt, cfg, AF_INET6, extack);
1248 default:
1249 NL_SET_ERR_MSG(extack, "table or vrftable must be specified");
1250 return -EINVAL;
1251 }
1252}
1253#endif
1254
1255static int input_action_end_dt6(struct sk_buff *skb,
1256 struct seg6_local_lwt *slwt)
1257{
1258 if (!decap_and_validate(skb, IPPROTO_IPV6))
1259 goto drop;
1260
1261 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
1262 goto drop;
1263
1264#ifdef CONFIG_NET_L3_MASTER_DEV
1265 if (seg6_end_dt6_get_mode(slwt) == DT_LEGACY_MODE)
1266 goto legacy_mode;
1267
1268 /* DT6_VRF_MODE */
1269 skb = end_dt_vrf_core(skb, slwt, AF_INET6);
1270 if (!skb)
1271 /* packet has been processed and consumed by the VRF */
1272 return 0;
1273
1274 if (IS_ERR(skb))
1275 return PTR_ERR(skb);
1276
1277 /* note: this time we do not need to specify the table because the VRF
1278 * takes care of selecting the correct table.
1279 */
1280 seg6_lookup_any_nexthop(skb, NULL, 0, true);
1281
1282 return dst_input(skb);
1283
1284legacy_mode:
1285#endif
1286 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
1287
1288 seg6_lookup_any_nexthop(skb, NULL, slwt->table, true);
1289
1290 return dst_input(skb);
1291
1292drop:
1293 kfree_skb(skb);
1294 return -EINVAL;
1295}
1296
1297#ifdef CONFIG_NET_L3_MASTER_DEV
1298static int seg6_end_dt46_build(struct seg6_local_lwt *slwt, const void *cfg,
1299 struct netlink_ext_ack *extack)
1300{
1301 return __seg6_end_dt_vrf_build(slwt, cfg, AF_UNSPEC, extack);
1302}
1303
1304static int input_action_end_dt46(struct sk_buff *skb,
1305 struct seg6_local_lwt *slwt)
1306{
1307 unsigned int off = 0;
1308 int nexthdr;
1309
1310 nexthdr = ipv6_find_hdr(skb, &off, -1, NULL, NULL);
1311 if (unlikely(nexthdr < 0))
1312 goto drop;
1313
1314 switch (nexthdr) {
1315 case IPPROTO_IPIP:
1316 return input_action_end_dt4(skb, slwt);
1317 case IPPROTO_IPV6:
1318 return input_action_end_dt6(skb, slwt);
1319 }
1320
1321drop:
1322 kfree_skb(skb);
1323 return -EINVAL;
1324}
1325#endif
1326
1327/* push an SRH on top of the current one */
1328static int input_action_end_b6(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1329{
1330 struct ipv6_sr_hdr *srh;
1331 int err = -EINVAL;
1332
1333 srh = get_and_validate_srh(skb);
1334 if (!srh)
1335 goto drop;
1336
1337 err = seg6_do_srh_inline(skb, slwt->srh);
1338 if (err)
1339 goto drop;
1340
1341 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
1342
1343 seg6_lookup_nexthop(skb, NULL, 0);
1344
1345 return dst_input(skb);
1346
1347drop:
1348 kfree_skb(skb);
1349 return err;
1350}
1351
1352/* encapsulate within an outer IPv6 header and a specified SRH */
1353static int input_action_end_b6_encap(struct sk_buff *skb,
1354 struct seg6_local_lwt *slwt)
1355{
1356 struct ipv6_sr_hdr *srh;
1357 int err = -EINVAL;
1358
1359 srh = get_and_validate_srh(skb);
1360 if (!srh)
1361 goto drop;
1362
1363 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
1364
1365 skb_reset_inner_headers(skb);
1366 skb->encapsulation = 1;
1367
1368 err = seg6_do_srh_encap(skb, slwt->srh, IPPROTO_IPV6);
1369 if (err)
1370 goto drop;
1371
1372 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
1373
1374 seg6_lookup_nexthop(skb, NULL, 0);
1375
1376 return dst_input(skb);
1377
1378drop:
1379 kfree_skb(skb);
1380 return err;
1381}
1382
1383DEFINE_PER_CPU(struct seg6_bpf_srh_state, seg6_bpf_srh_states);
1384
1385bool seg6_bpf_has_valid_srh(struct sk_buff *skb)
1386{
1387 struct seg6_bpf_srh_state *srh_state =
1388 this_cpu_ptr(&seg6_bpf_srh_states);
1389 struct ipv6_sr_hdr *srh = srh_state->srh;
1390
1391 if (unlikely(srh == NULL))
1392 return false;
1393
1394 if (unlikely(!srh_state->valid)) {
1395 if ((srh_state->hdrlen & 7) != 0)
1396 return false;
1397
1398 srh->hdrlen = (u8)(srh_state->hdrlen >> 3);
1399 if (!seg6_validate_srh(srh, (srh->hdrlen + 1) << 3, true))
1400 return false;
1401
1402 srh_state->valid = true;
1403 }
1404
1405 return true;
1406}
1407
1408static int input_action_end_bpf(struct sk_buff *skb,
1409 struct seg6_local_lwt *slwt)
1410{
1411 struct seg6_bpf_srh_state *srh_state =
1412 this_cpu_ptr(&seg6_bpf_srh_states);
1413 struct ipv6_sr_hdr *srh;
1414 int ret;
1415
1416 srh = get_and_validate_srh(skb);
1417 if (!srh) {
1418 kfree_skb(skb);
1419 return -EINVAL;
1420 }
1421 advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
1422
1423 /* preempt_disable is needed to protect the per-CPU buffer srh_state,
1424 * which is also accessed by the bpf_lwt_seg6_* helpers
1425 */
1426 preempt_disable();
1427 srh_state->srh = srh;
1428 srh_state->hdrlen = srh->hdrlen << 3;
1429 srh_state->valid = true;
1430
1431 rcu_read_lock();
1432 bpf_compute_data_pointers(skb);
1433 ret = bpf_prog_run_save_cb(slwt->bpf.prog, skb);
1434 rcu_read_unlock();
1435
1436 switch (ret) {
1437 case BPF_OK:
1438 case BPF_REDIRECT:
1439 break;
1440 case BPF_DROP:
1441 goto drop;
1442 default:
1443 pr_warn_once("bpf-seg6local: Illegal return value %u\n", ret);
1444 goto drop;
1445 }
1446
1447 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
1448 goto drop;
1449
1450 preempt_enable();
1451 if (ret != BPF_REDIRECT)
1452 seg6_lookup_nexthop(skb, NULL, 0);
1453
1454 return dst_input(skb);
1455
1456drop:
1457 preempt_enable();
1458 kfree_skb(skb);
1459 return -EINVAL;
1460}
1461
1462static struct seg6_action_desc seg6_action_table[] = {
1463 {
1464 .action = SEG6_LOCAL_ACTION_END,
1465 .attrs = 0,
1466 .optattrs = SEG6_F_LOCAL_COUNTERS |
1467 SEG6_F_LOCAL_FLAVORS,
1468 .input = input_action_end,
1469 },
1470 {
1471 .action = SEG6_LOCAL_ACTION_END_X,
1472 .attrs = SEG6_F_ATTR(SEG6_LOCAL_NH6),
1473 .optattrs = SEG6_F_LOCAL_COUNTERS |
1474 SEG6_F_LOCAL_FLAVORS,
1475 .input = input_action_end_x,
1476 },
1477 {
1478 .action = SEG6_LOCAL_ACTION_END_T,
1479 .attrs = SEG6_F_ATTR(SEG6_LOCAL_TABLE),
1480 .optattrs = SEG6_F_LOCAL_COUNTERS,
1481 .input = input_action_end_t,
1482 },
1483 {
1484 .action = SEG6_LOCAL_ACTION_END_DX2,
1485 .attrs = SEG6_F_ATTR(SEG6_LOCAL_OIF),
1486 .optattrs = SEG6_F_LOCAL_COUNTERS,
1487 .input = input_action_end_dx2,
1488 },
1489 {
1490 .action = SEG6_LOCAL_ACTION_END_DX6,
1491 .attrs = SEG6_F_ATTR(SEG6_LOCAL_NH6),
1492 .optattrs = SEG6_F_LOCAL_COUNTERS,
1493 .input = input_action_end_dx6,
1494 },
1495 {
1496 .action = SEG6_LOCAL_ACTION_END_DX4,
1497 .attrs = SEG6_F_ATTR(SEG6_LOCAL_NH4),
1498 .optattrs = SEG6_F_LOCAL_COUNTERS,
1499 .input = input_action_end_dx4,
1500 },
1501 {
1502 .action = SEG6_LOCAL_ACTION_END_DT4,
1503 .attrs = SEG6_F_ATTR(SEG6_LOCAL_VRFTABLE),
1504 .optattrs = SEG6_F_LOCAL_COUNTERS,
1505#ifdef CONFIG_NET_L3_MASTER_DEV
1506 .input = input_action_end_dt4,
1507 .slwt_ops = {
1508 .build_state = seg6_end_dt4_build,
1509 },
1510#endif
1511 },
1512 {
1513 .action = SEG6_LOCAL_ACTION_END_DT6,
1514#ifdef CONFIG_NET_L3_MASTER_DEV
1515 .attrs = 0,
1516 .optattrs = SEG6_F_LOCAL_COUNTERS |
1517 SEG6_F_ATTR(SEG6_LOCAL_TABLE) |
1518 SEG6_F_ATTR(SEG6_LOCAL_VRFTABLE),
1519 .slwt_ops = {
1520 .build_state = seg6_end_dt6_build,
1521 },
1522#else
1523 .attrs = SEG6_F_ATTR(SEG6_LOCAL_TABLE),
1524 .optattrs = SEG6_F_LOCAL_COUNTERS,
1525#endif
1526 .input = input_action_end_dt6,
1527 },
1528 {
1529 .action = SEG6_LOCAL_ACTION_END_DT46,
1530 .attrs = SEG6_F_ATTR(SEG6_LOCAL_VRFTABLE),
1531 .optattrs = SEG6_F_LOCAL_COUNTERS,
1532#ifdef CONFIG_NET_L3_MASTER_DEV
1533 .input = input_action_end_dt46,
1534 .slwt_ops = {
1535 .build_state = seg6_end_dt46_build,
1536 },
1537#endif
1538 },
1539 {
1540 .action = SEG6_LOCAL_ACTION_END_B6,
1541 .attrs = SEG6_F_ATTR(SEG6_LOCAL_SRH),
1542 .optattrs = SEG6_F_LOCAL_COUNTERS,
1543 .input = input_action_end_b6,
1544 },
1545 {
1546 .action = SEG6_LOCAL_ACTION_END_B6_ENCAP,
1547 .attrs = SEG6_F_ATTR(SEG6_LOCAL_SRH),
1548 .optattrs = SEG6_F_LOCAL_COUNTERS,
1549 .input = input_action_end_b6_encap,
1550 .static_headroom = sizeof(struct ipv6hdr),
1551 },
1552 {
1553 .action = SEG6_LOCAL_ACTION_END_BPF,
1554 .attrs = SEG6_F_ATTR(SEG6_LOCAL_BPF),
1555 .optattrs = SEG6_F_LOCAL_COUNTERS,
1556 .input = input_action_end_bpf,
1557 },
1558
1559};
1560
1561static struct seg6_action_desc *__get_action_desc(int action)
1562{
1563 struct seg6_action_desc *desc;
1564 int i, count;
1565
1566 count = ARRAY_SIZE(seg6_action_table);
1567 for (i = 0; i < count; i++) {
1568 desc = &seg6_action_table[i];
1569 if (desc->action == action)
1570 return desc;
1571 }
1572
1573 return NULL;
1574}
1575
1576static bool seg6_lwtunnel_counters_enabled(struct seg6_local_lwt *slwt)
1577{
1578 return slwt->parsed_optattrs & SEG6_F_LOCAL_COUNTERS;
1579}
1580
1581static void seg6_local_update_counters(struct seg6_local_lwt *slwt,
1582 unsigned int len, int err)
1583{
1584 struct pcpu_seg6_local_counters *pcounters;
1585
1586 pcounters = this_cpu_ptr(slwt->pcpu_counters);
1587 u64_stats_update_begin(&pcounters->syncp);
1588
1589 if (likely(!err)) {
1590 u64_stats_inc(&pcounters->packets);
1591 u64_stats_add(&pcounters->bytes, len);
1592 } else {
1593 u64_stats_inc(&pcounters->errors);
1594 }
1595
1596 u64_stats_update_end(&pcounters->syncp);
1597}
1598
1599static int seg6_local_input_core(struct net *net, struct sock *sk,
1600 struct sk_buff *skb)
1601{
1602 struct dst_entry *orig_dst = skb_dst(skb);
1603 struct seg6_action_desc *desc;
1604 struct seg6_local_lwt *slwt;
1605 unsigned int len = skb->len;
1606 int rc;
1607
1608 slwt = seg6_local_lwtunnel(orig_dst->lwtstate);
1609 desc = slwt->desc;
1610
1611 rc = desc->input(skb, slwt);
1612
1613 if (!seg6_lwtunnel_counters_enabled(slwt))
1614 return rc;
1615
1616 seg6_local_update_counters(slwt, len, rc);
1617
1618 return rc;
1619}
1620
1621static int seg6_local_input(struct sk_buff *skb)
1622{
1623 if (skb->protocol != htons(ETH_P_IPV6)) {
1624 kfree_skb(skb);
1625 return -EINVAL;
1626 }
1627
1628 if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
1629 return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_IN,
1630 dev_net(skb->dev), NULL, skb, skb->dev, NULL,
1631 seg6_local_input_core);
1632
1633 return seg6_local_input_core(dev_net(skb->dev), NULL, skb);
1634}
1635
1636static const struct nla_policy seg6_local_policy[SEG6_LOCAL_MAX + 1] = {
1637 [SEG6_LOCAL_ACTION] = { .type = NLA_U32 },
1638 [SEG6_LOCAL_SRH] = { .type = NLA_BINARY },
1639 [SEG6_LOCAL_TABLE] = { .type = NLA_U32 },
1640 [SEG6_LOCAL_VRFTABLE] = { .type = NLA_U32 },
1641 [SEG6_LOCAL_NH4] = { .type = NLA_BINARY,
1642 .len = sizeof(struct in_addr) },
1643 [SEG6_LOCAL_NH6] = { .type = NLA_BINARY,
1644 .len = sizeof(struct in6_addr) },
1645 [SEG6_LOCAL_IIF] = { .type = NLA_U32 },
1646 [SEG6_LOCAL_OIF] = { .type = NLA_U32 },
1647 [SEG6_LOCAL_BPF] = { .type = NLA_NESTED },
1648 [SEG6_LOCAL_COUNTERS] = { .type = NLA_NESTED },
1649 [SEG6_LOCAL_FLAVORS] = { .type = NLA_NESTED },
1650};
1651
1652static int parse_nla_srh(struct nlattr **attrs, struct seg6_local_lwt *slwt,
1653 struct netlink_ext_ack *extack)
1654{
1655 struct ipv6_sr_hdr *srh;
1656 int len;
1657
1658 srh = nla_data(attrs[SEG6_LOCAL_SRH]);
1659 len = nla_len(attrs[SEG6_LOCAL_SRH]);
1660
1661 /* SRH must contain at least one segment */
1662 if (len < sizeof(*srh) + sizeof(struct in6_addr))
1663 return -EINVAL;
1664
1665 if (!seg6_validate_srh(srh, len, false))
1666 return -EINVAL;
1667
1668 slwt->srh = kmemdup(srh, len, GFP_KERNEL);
1669 if (!slwt->srh)
1670 return -ENOMEM;
1671
1672 slwt->headroom += len;
1673
1674 return 0;
1675}
1676
1677static int put_nla_srh(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1678{
1679 struct ipv6_sr_hdr *srh;
1680 struct nlattr *nla;
1681 int len;
1682
1683 srh = slwt->srh;
1684 len = (srh->hdrlen + 1) << 3;
1685
1686 nla = nla_reserve(skb, SEG6_LOCAL_SRH, len);
1687 if (!nla)
1688 return -EMSGSIZE;
1689
1690 memcpy(nla_data(nla), srh, len);
1691
1692 return 0;
1693}
1694
1695static int cmp_nla_srh(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
1696{
1697 int len = (a->srh->hdrlen + 1) << 3;
1698
1699 if (len != ((b->srh->hdrlen + 1) << 3))
1700 return 1;
1701
1702 return memcmp(a->srh, b->srh, len);
1703}
1704
1705static void destroy_attr_srh(struct seg6_local_lwt *slwt)
1706{
1707 kfree(slwt->srh);
1708}
1709
1710static int parse_nla_table(struct nlattr **attrs, struct seg6_local_lwt *slwt,
1711 struct netlink_ext_ack *extack)
1712{
1713 slwt->table = nla_get_u32(attrs[SEG6_LOCAL_TABLE]);
1714
1715 return 0;
1716}
1717
1718static int put_nla_table(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1719{
1720 if (nla_put_u32(skb, SEG6_LOCAL_TABLE, slwt->table))
1721 return -EMSGSIZE;
1722
1723 return 0;
1724}
1725
1726static int cmp_nla_table(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
1727{
1728 if (a->table != b->table)
1729 return 1;
1730
1731 return 0;
1732}
1733
1734static struct
1735seg6_end_dt_info *seg6_possible_end_dt_info(struct seg6_local_lwt *slwt)
1736{
1737#ifdef CONFIG_NET_L3_MASTER_DEV
1738 return &slwt->dt_info;
1739#else
1740 return ERR_PTR(-EOPNOTSUPP);
1741#endif
1742}
1743
1744static int parse_nla_vrftable(struct nlattr **attrs,
1745 struct seg6_local_lwt *slwt,
1746 struct netlink_ext_ack *extack)
1747{
1748 struct seg6_end_dt_info *info = seg6_possible_end_dt_info(slwt);
1749
1750 if (IS_ERR(info))
1751 return PTR_ERR(info);
1752
1753 info->vrf_table = nla_get_u32(attrs[SEG6_LOCAL_VRFTABLE]);
1754
1755 return 0;
1756}
1757
1758static int put_nla_vrftable(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1759{
1760 struct seg6_end_dt_info *info = seg6_possible_end_dt_info(slwt);
1761
1762 if (IS_ERR(info))
1763 return PTR_ERR(info);
1764
1765 if (nla_put_u32(skb, SEG6_LOCAL_VRFTABLE, info->vrf_table))
1766 return -EMSGSIZE;
1767
1768 return 0;
1769}
1770
1771static int cmp_nla_vrftable(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
1772{
1773 struct seg6_end_dt_info *info_a = seg6_possible_end_dt_info(a);
1774 struct seg6_end_dt_info *info_b = seg6_possible_end_dt_info(b);
1775
1776 if (info_a->vrf_table != info_b->vrf_table)
1777 return 1;
1778
1779 return 0;
1780}
1781
1782static int parse_nla_nh4(struct nlattr **attrs, struct seg6_local_lwt *slwt,
1783 struct netlink_ext_ack *extack)
1784{
1785 memcpy(&slwt->nh4, nla_data(attrs[SEG6_LOCAL_NH4]),
1786 sizeof(struct in_addr));
1787
1788 return 0;
1789}
1790
1791static int put_nla_nh4(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1792{
1793 struct nlattr *nla;
1794
1795 nla = nla_reserve(skb, SEG6_LOCAL_NH4, sizeof(struct in_addr));
1796 if (!nla)
1797 return -EMSGSIZE;
1798
1799 memcpy(nla_data(nla), &slwt->nh4, sizeof(struct in_addr));
1800
1801 return 0;
1802}
1803
1804static int cmp_nla_nh4(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
1805{
1806 return memcmp(&a->nh4, &b->nh4, sizeof(struct in_addr));
1807}
1808
1809static int parse_nla_nh6(struct nlattr **attrs, struct seg6_local_lwt *slwt,
1810 struct netlink_ext_ack *extack)
1811{
1812 memcpy(&slwt->nh6, nla_data(attrs[SEG6_LOCAL_NH6]),
1813 sizeof(struct in6_addr));
1814
1815 return 0;
1816}
1817
1818static int put_nla_nh6(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1819{
1820 struct nlattr *nla;
1821
1822 nla = nla_reserve(skb, SEG6_LOCAL_NH6, sizeof(struct in6_addr));
1823 if (!nla)
1824 return -EMSGSIZE;
1825
1826 memcpy(nla_data(nla), &slwt->nh6, sizeof(struct in6_addr));
1827
1828 return 0;
1829}
1830
1831static int cmp_nla_nh6(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
1832{
1833 return memcmp(&a->nh6, &b->nh6, sizeof(struct in6_addr));
1834}
1835
1836static int parse_nla_iif(struct nlattr **attrs, struct seg6_local_lwt *slwt,
1837 struct netlink_ext_ack *extack)
1838{
1839 slwt->iif = nla_get_u32(attrs[SEG6_LOCAL_IIF]);
1840
1841 return 0;
1842}
1843
1844static int put_nla_iif(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1845{
1846 if (nla_put_u32(skb, SEG6_LOCAL_IIF, slwt->iif))
1847 return -EMSGSIZE;
1848
1849 return 0;
1850}
1851
1852static int cmp_nla_iif(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
1853{
1854 if (a->iif != b->iif)
1855 return 1;
1856
1857 return 0;
1858}
1859
1860static int parse_nla_oif(struct nlattr **attrs, struct seg6_local_lwt *slwt,
1861 struct netlink_ext_ack *extack)
1862{
1863 slwt->oif = nla_get_u32(attrs[SEG6_LOCAL_OIF]);
1864
1865 return 0;
1866}
1867
1868static int put_nla_oif(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1869{
1870 if (nla_put_u32(skb, SEG6_LOCAL_OIF, slwt->oif))
1871 return -EMSGSIZE;
1872
1873 return 0;
1874}
1875
1876static int cmp_nla_oif(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
1877{
1878 if (a->oif != b->oif)
1879 return 1;
1880
1881 return 0;
1882}
1883
1884#define MAX_PROG_NAME 256
1885static const struct nla_policy bpf_prog_policy[SEG6_LOCAL_BPF_PROG_MAX + 1] = {
1886 [SEG6_LOCAL_BPF_PROG] = { .type = NLA_U32, },
1887 [SEG6_LOCAL_BPF_PROG_NAME] = { .type = NLA_NUL_STRING,
1888 .len = MAX_PROG_NAME },
1889};
1890
1891static int parse_nla_bpf(struct nlattr **attrs, struct seg6_local_lwt *slwt,
1892 struct netlink_ext_ack *extack)
1893{
1894 struct nlattr *tb[SEG6_LOCAL_BPF_PROG_MAX + 1];
1895 struct bpf_prog *p;
1896 int ret;
1897 u32 fd;
1898
1899 ret = nla_parse_nested_deprecated(tb, SEG6_LOCAL_BPF_PROG_MAX,
1900 attrs[SEG6_LOCAL_BPF],
1901 bpf_prog_policy, NULL);
1902 if (ret < 0)
1903 return ret;
1904
1905 if (!tb[SEG6_LOCAL_BPF_PROG] || !tb[SEG6_LOCAL_BPF_PROG_NAME])
1906 return -EINVAL;
1907
1908 slwt->bpf.name = nla_memdup(tb[SEG6_LOCAL_BPF_PROG_NAME], GFP_KERNEL);
1909 if (!slwt->bpf.name)
1910 return -ENOMEM;
1911
1912 fd = nla_get_u32(tb[SEG6_LOCAL_BPF_PROG]);
1913 p = bpf_prog_get_type(fd, BPF_PROG_TYPE_LWT_SEG6LOCAL);
1914 if (IS_ERR(p)) {
1915 kfree(slwt->bpf.name);
1916 return PTR_ERR(p);
1917 }
1918
1919 slwt->bpf.prog = p;
1920 return 0;
1921}
1922
1923static int put_nla_bpf(struct sk_buff *skb, struct seg6_local_lwt *slwt)
1924{
1925 struct nlattr *nest;
1926
1927 if (!slwt->bpf.prog)
1928 return 0;
1929
1930 nest = nla_nest_start_noflag(skb, SEG6_LOCAL_BPF);
1931 if (!nest)
1932 return -EMSGSIZE;
1933
1934 if (nla_put_u32(skb, SEG6_LOCAL_BPF_PROG, slwt->bpf.prog->aux->id))
1935 return -EMSGSIZE;
1936
1937 if (slwt->bpf.name &&
1938 nla_put_string(skb, SEG6_LOCAL_BPF_PROG_NAME, slwt->bpf.name))
1939 return -EMSGSIZE;
1940
1941 return nla_nest_end(skb, nest);
1942}
1943
1944static int cmp_nla_bpf(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
1945{
1946 if (!a->bpf.name && !b->bpf.name)
1947 return 0;
1948
1949 if (!a->bpf.name || !b->bpf.name)
1950 return 1;
1951
1952 return strcmp(a->bpf.name, b->bpf.name);
1953}
1954
1955static void destroy_attr_bpf(struct seg6_local_lwt *slwt)
1956{
1957 kfree(slwt->bpf.name);
1958 if (slwt->bpf.prog)
1959 bpf_prog_put(slwt->bpf.prog);
1960}
1961
1962static const struct
1963nla_policy seg6_local_counters_policy[SEG6_LOCAL_CNT_MAX + 1] = {
1964 [SEG6_LOCAL_CNT_PACKETS] = { .type = NLA_U64 },
1965 [SEG6_LOCAL_CNT_BYTES] = { .type = NLA_U64 },
1966 [SEG6_LOCAL_CNT_ERRORS] = { .type = NLA_U64 },
1967};
1968
1969static int parse_nla_counters(struct nlattr **attrs,
1970 struct seg6_local_lwt *slwt,
1971 struct netlink_ext_ack *extack)
1972{
1973 struct pcpu_seg6_local_counters __percpu *pcounters;
1974 struct nlattr *tb[SEG6_LOCAL_CNT_MAX + 1];
1975 int ret;
1976
1977 ret = nla_parse_nested_deprecated(tb, SEG6_LOCAL_CNT_MAX,
1978 attrs[SEG6_LOCAL_COUNTERS],
1979 seg6_local_counters_policy, NULL);
1980 if (ret < 0)
1981 return ret;
1982
1983 /* basic support for SRv6 Behavior counters requires at least:
1984 * packets, bytes and errors.
1985 */
1986 if (!tb[SEG6_LOCAL_CNT_PACKETS] || !tb[SEG6_LOCAL_CNT_BYTES] ||
1987 !tb[SEG6_LOCAL_CNT_ERRORS])
1988 return -EINVAL;
1989
1990 /* counters are always zero initialized */
1991 pcounters = seg6_local_alloc_pcpu_counters(GFP_KERNEL);
1992 if (!pcounters)
1993 return -ENOMEM;
1994
1995 slwt->pcpu_counters = pcounters;
1996
1997 return 0;
1998}
1999
2000static int seg6_local_fill_nla_counters(struct sk_buff *skb,
2001 struct seg6_local_counters *counters)
2002{
2003 if (nla_put_u64_64bit(skb, SEG6_LOCAL_CNT_PACKETS, counters->packets,
2004 SEG6_LOCAL_CNT_PAD))
2005 return -EMSGSIZE;
2006
2007 if (nla_put_u64_64bit(skb, SEG6_LOCAL_CNT_BYTES, counters->bytes,
2008 SEG6_LOCAL_CNT_PAD))
2009 return -EMSGSIZE;
2010
2011 if (nla_put_u64_64bit(skb, SEG6_LOCAL_CNT_ERRORS, counters->errors,
2012 SEG6_LOCAL_CNT_PAD))
2013 return -EMSGSIZE;
2014
2015 return 0;
2016}
2017
2018static int put_nla_counters(struct sk_buff *skb, struct seg6_local_lwt *slwt)
2019{
2020 struct seg6_local_counters counters = { 0, 0, 0 };
2021 struct nlattr *nest;
2022 int rc, i;
2023
2024 nest = nla_nest_start(skb, SEG6_LOCAL_COUNTERS);
2025 if (!nest)
2026 return -EMSGSIZE;
2027
2028 for_each_possible_cpu(i) {
2029 struct pcpu_seg6_local_counters *pcounters;
2030 u64 packets, bytes, errors;
2031 unsigned int start;
2032
2033 pcounters = per_cpu_ptr(slwt->pcpu_counters, i);
2034 do {
2035 start = u64_stats_fetch_begin(&pcounters->syncp);
2036
2037 packets = u64_stats_read(&pcounters->packets);
2038 bytes = u64_stats_read(&pcounters->bytes);
2039 errors = u64_stats_read(&pcounters->errors);
2040
2041 } while (u64_stats_fetch_retry(&pcounters->syncp, start));
2042
2043 counters.packets += packets;
2044 counters.bytes += bytes;
2045 counters.errors += errors;
2046 }
2047
2048 rc = seg6_local_fill_nla_counters(skb, &counters);
2049 if (rc < 0) {
2050 nla_nest_cancel(skb, nest);
2051 return rc;
2052 }
2053
2054 return nla_nest_end(skb, nest);
2055}
2056
2057static int cmp_nla_counters(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
2058{
2059 /* a and b are equal if both have pcpu_counters set or not */
2060 return (!!((unsigned long)a->pcpu_counters)) ^
2061 (!!((unsigned long)b->pcpu_counters));
2062}
2063
2064static void destroy_attr_counters(struct seg6_local_lwt *slwt)
2065{
2066 free_percpu(slwt->pcpu_counters);
2067}
2068
2069static const
2070struct nla_policy seg6_local_flavors_policy[SEG6_LOCAL_FLV_MAX + 1] = {
2071 [SEG6_LOCAL_FLV_OPERATION] = { .type = NLA_U32 },
2072 [SEG6_LOCAL_FLV_LCBLOCK_BITS] = { .type = NLA_U8 },
2073 [SEG6_LOCAL_FLV_LCNODE_FN_BITS] = { .type = NLA_U8 },
2074};
2075
2076/* check whether the lengths of the Locator-Block and Locator-Node Function
2077 * are compatible with the dimension of a C-SID container.
2078 */
2079static int seg6_chk_next_csid_cfg(__u8 block_len, __u8 func_len)
2080{
2081 /* Locator-Block and Locator-Node Function cannot exceed 128 bits
2082 * (i.e. C-SID container lenghts).
2083 */
2084 if (next_csid_chk_cntr_bits(block_len, func_len))
2085 return -EINVAL;
2086
2087 /* Locator-Block length must be greater than zero and evenly divisible
2088 * by 8. There must be room for a Locator-Node Function, at least.
2089 */
2090 if (next_csid_chk_lcblock_bits(block_len))
2091 return -EINVAL;
2092
2093 /* Locator-Node Function length must be greater than zero and evenly
2094 * divisible by 8. There must be room for the Locator-Block.
2095 */
2096 if (next_csid_chk_lcnode_fn_bits(func_len))
2097 return -EINVAL;
2098
2099 return 0;
2100}
2101
2102static int seg6_parse_nla_next_csid_cfg(struct nlattr **tb,
2103 struct seg6_flavors_info *finfo,
2104 struct netlink_ext_ack *extack)
2105{
2106 __u8 func_len = SEG6_LOCAL_LCNODE_FN_DBITS;
2107 __u8 block_len = SEG6_LOCAL_LCBLOCK_DBITS;
2108 int rc;
2109
2110 if (tb[SEG6_LOCAL_FLV_LCBLOCK_BITS])
2111 block_len = nla_get_u8(tb[SEG6_LOCAL_FLV_LCBLOCK_BITS]);
2112
2113 if (tb[SEG6_LOCAL_FLV_LCNODE_FN_BITS])
2114 func_len = nla_get_u8(tb[SEG6_LOCAL_FLV_LCNODE_FN_BITS]);
2115
2116 rc = seg6_chk_next_csid_cfg(block_len, func_len);
2117 if (rc < 0) {
2118 NL_SET_ERR_MSG(extack,
2119 "Invalid Locator Block/Node Function lengths");
2120 return rc;
2121 }
2122
2123 finfo->lcblock_bits = block_len;
2124 finfo->lcnode_func_bits = func_len;
2125
2126 return 0;
2127}
2128
2129static int parse_nla_flavors(struct nlattr **attrs, struct seg6_local_lwt *slwt,
2130 struct netlink_ext_ack *extack)
2131{
2132 struct seg6_flavors_info *finfo = &slwt->flv_info;
2133 struct nlattr *tb[SEG6_LOCAL_FLV_MAX + 1];
2134 int action = slwt->action;
2135 __u32 fops, supp_fops;
2136 int rc;
2137
2138 rc = nla_parse_nested_deprecated(tb, SEG6_LOCAL_FLV_MAX,
2139 attrs[SEG6_LOCAL_FLAVORS],
2140 seg6_local_flavors_policy, NULL);
2141 if (rc < 0)
2142 return rc;
2143
2144 /* this attribute MUST always be present since it represents the Flavor
2145 * operation(s) to be carried out.
2146 */
2147 if (!tb[SEG6_LOCAL_FLV_OPERATION])
2148 return -EINVAL;
2149
2150 fops = nla_get_u32(tb[SEG6_LOCAL_FLV_OPERATION]);
2151 rc = seg6_flv_supp_ops_by_action(action, &supp_fops);
2152 if (rc < 0 || (fops & ~supp_fops)) {
2153 NL_SET_ERR_MSG(extack, "Unsupported Flavor operation(s)");
2154 return -EOPNOTSUPP;
2155 }
2156
2157 finfo->flv_ops = fops;
2158
2159 if (seg6_next_csid_enabled(fops)) {
2160 /* Locator-Block and Locator-Node Function lengths can be
2161 * provided by the user space. Otherwise, default values are
2162 * applied.
2163 */
2164 rc = seg6_parse_nla_next_csid_cfg(tb, finfo, extack);
2165 if (rc < 0)
2166 return rc;
2167 }
2168
2169 return 0;
2170}
2171
2172static int seg6_fill_nla_next_csid_cfg(struct sk_buff *skb,
2173 struct seg6_flavors_info *finfo)
2174{
2175 if (nla_put_u8(skb, SEG6_LOCAL_FLV_LCBLOCK_BITS, finfo->lcblock_bits))
2176 return -EMSGSIZE;
2177
2178 if (nla_put_u8(skb, SEG6_LOCAL_FLV_LCNODE_FN_BITS,
2179 finfo->lcnode_func_bits))
2180 return -EMSGSIZE;
2181
2182 return 0;
2183}
2184
2185static int put_nla_flavors(struct sk_buff *skb, struct seg6_local_lwt *slwt)
2186{
2187 struct seg6_flavors_info *finfo = &slwt->flv_info;
2188 __u32 fops = finfo->flv_ops;
2189 struct nlattr *nest;
2190 int rc;
2191
2192 nest = nla_nest_start(skb, SEG6_LOCAL_FLAVORS);
2193 if (!nest)
2194 return -EMSGSIZE;
2195
2196 if (nla_put_u32(skb, SEG6_LOCAL_FLV_OPERATION, fops)) {
2197 rc = -EMSGSIZE;
2198 goto err;
2199 }
2200
2201 if (seg6_next_csid_enabled(fops)) {
2202 rc = seg6_fill_nla_next_csid_cfg(skb, finfo);
2203 if (rc < 0)
2204 goto err;
2205 }
2206
2207 return nla_nest_end(skb, nest);
2208
2209err:
2210 nla_nest_cancel(skb, nest);
2211 return rc;
2212}
2213
2214static int seg6_cmp_nla_next_csid_cfg(struct seg6_flavors_info *finfo_a,
2215 struct seg6_flavors_info *finfo_b)
2216{
2217 if (finfo_a->lcblock_bits != finfo_b->lcblock_bits)
2218 return 1;
2219
2220 if (finfo_a->lcnode_func_bits != finfo_b->lcnode_func_bits)
2221 return 1;
2222
2223 return 0;
2224}
2225
2226static int cmp_nla_flavors(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
2227{
2228 struct seg6_flavors_info *finfo_a = &a->flv_info;
2229 struct seg6_flavors_info *finfo_b = &b->flv_info;
2230
2231 if (finfo_a->flv_ops != finfo_b->flv_ops)
2232 return 1;
2233
2234 if (seg6_next_csid_enabled(finfo_a->flv_ops)) {
2235 if (seg6_cmp_nla_next_csid_cfg(finfo_a, finfo_b))
2236 return 1;
2237 }
2238
2239 return 0;
2240}
2241
2242static int encap_size_flavors(struct seg6_local_lwt *slwt)
2243{
2244 struct seg6_flavors_info *finfo = &slwt->flv_info;
2245 int nlsize;
2246
2247 nlsize = nla_total_size(0) + /* nest SEG6_LOCAL_FLAVORS */
2248 nla_total_size(4); /* SEG6_LOCAL_FLV_OPERATION */
2249
2250 if (seg6_next_csid_enabled(finfo->flv_ops))
2251 nlsize += nla_total_size(1) + /* SEG6_LOCAL_FLV_LCBLOCK_BITS */
2252 nla_total_size(1); /* SEG6_LOCAL_FLV_LCNODE_FN_BITS */
2253
2254 return nlsize;
2255}
2256
2257struct seg6_action_param {
2258 int (*parse)(struct nlattr **attrs, struct seg6_local_lwt *slwt,
2259 struct netlink_ext_ack *extack);
2260 int (*put)(struct sk_buff *skb, struct seg6_local_lwt *slwt);
2261 int (*cmp)(struct seg6_local_lwt *a, struct seg6_local_lwt *b);
2262
2263 /* optional destroy() callback useful for releasing resources which
2264 * have been previously acquired in the corresponding parse()
2265 * function.
2266 */
2267 void (*destroy)(struct seg6_local_lwt *slwt);
2268};
2269
2270static struct seg6_action_param seg6_action_params[SEG6_LOCAL_MAX + 1] = {
2271 [SEG6_LOCAL_SRH] = { .parse = parse_nla_srh,
2272 .put = put_nla_srh,
2273 .cmp = cmp_nla_srh,
2274 .destroy = destroy_attr_srh },
2275
2276 [SEG6_LOCAL_TABLE] = { .parse = parse_nla_table,
2277 .put = put_nla_table,
2278 .cmp = cmp_nla_table },
2279
2280 [SEG6_LOCAL_NH4] = { .parse = parse_nla_nh4,
2281 .put = put_nla_nh4,
2282 .cmp = cmp_nla_nh4 },
2283
2284 [SEG6_LOCAL_NH6] = { .parse = parse_nla_nh6,
2285 .put = put_nla_nh6,
2286 .cmp = cmp_nla_nh6 },
2287
2288 [SEG6_LOCAL_IIF] = { .parse = parse_nla_iif,
2289 .put = put_nla_iif,
2290 .cmp = cmp_nla_iif },
2291
2292 [SEG6_LOCAL_OIF] = { .parse = parse_nla_oif,
2293 .put = put_nla_oif,
2294 .cmp = cmp_nla_oif },
2295
2296 [SEG6_LOCAL_BPF] = { .parse = parse_nla_bpf,
2297 .put = put_nla_bpf,
2298 .cmp = cmp_nla_bpf,
2299 .destroy = destroy_attr_bpf },
2300
2301 [SEG6_LOCAL_VRFTABLE] = { .parse = parse_nla_vrftable,
2302 .put = put_nla_vrftable,
2303 .cmp = cmp_nla_vrftable },
2304
2305 [SEG6_LOCAL_COUNTERS] = { .parse = parse_nla_counters,
2306 .put = put_nla_counters,
2307 .cmp = cmp_nla_counters,
2308 .destroy = destroy_attr_counters },
2309
2310 [SEG6_LOCAL_FLAVORS] = { .parse = parse_nla_flavors,
2311 .put = put_nla_flavors,
2312 .cmp = cmp_nla_flavors },
2313};
2314
2315/* call the destroy() callback (if available) for each set attribute in
2316 * @parsed_attrs, starting from the first attribute up to the @max_parsed
2317 * (excluded) attribute.
2318 */
2319static void __destroy_attrs(unsigned long parsed_attrs, int max_parsed,
2320 struct seg6_local_lwt *slwt)
2321{
2322 struct seg6_action_param *param;
2323 int i;
2324
2325 /* Every required seg6local attribute is identified by an ID which is
2326 * encoded as a flag (i.e: 1 << ID) in the 'attrs' bitmask;
2327 *
2328 * We scan the 'parsed_attrs' bitmask, starting from the first attribute
2329 * up to the @max_parsed (excluded) attribute.
2330 * For each set attribute, we retrieve the corresponding destroy()
2331 * callback. If the callback is not available, then we skip to the next
2332 * attribute; otherwise, we call the destroy() callback.
2333 */
2334 for (i = SEG6_LOCAL_SRH; i < max_parsed; ++i) {
2335 if (!(parsed_attrs & SEG6_F_ATTR(i)))
2336 continue;
2337
2338 param = &seg6_action_params[i];
2339
2340 if (param->destroy)
2341 param->destroy(slwt);
2342 }
2343}
2344
2345/* release all the resources that may have been acquired during parsing
2346 * operations.
2347 */
2348static void destroy_attrs(struct seg6_local_lwt *slwt)
2349{
2350 unsigned long attrs = slwt->desc->attrs | slwt->parsed_optattrs;
2351
2352 __destroy_attrs(attrs, SEG6_LOCAL_MAX + 1, slwt);
2353}
2354
2355static int parse_nla_optional_attrs(struct nlattr **attrs,
2356 struct seg6_local_lwt *slwt,
2357 struct netlink_ext_ack *extack)
2358{
2359 struct seg6_action_desc *desc = slwt->desc;
2360 unsigned long parsed_optattrs = 0;
2361 struct seg6_action_param *param;
2362 int err, i;
2363
2364 for (i = SEG6_LOCAL_SRH; i < SEG6_LOCAL_MAX + 1; ++i) {
2365 if (!(desc->optattrs & SEG6_F_ATTR(i)) || !attrs[i])
2366 continue;
2367
2368 /* once here, the i-th attribute is provided by the
2369 * userspace AND it is identified optional as well.
2370 */
2371 param = &seg6_action_params[i];
2372
2373 err = param->parse(attrs, slwt, extack);
2374 if (err < 0)
2375 goto parse_optattrs_err;
2376
2377 /* current attribute has been correctly parsed */
2378 parsed_optattrs |= SEG6_F_ATTR(i);
2379 }
2380
2381 /* store in the tunnel state all the optional attributed successfully
2382 * parsed.
2383 */
2384 slwt->parsed_optattrs = parsed_optattrs;
2385
2386 return 0;
2387
2388parse_optattrs_err:
2389 __destroy_attrs(parsed_optattrs, i, slwt);
2390
2391 return err;
2392}
2393
2394/* call the custom constructor of the behavior during its initialization phase
2395 * and after that all its attributes have been parsed successfully.
2396 */
2397static int
2398seg6_local_lwtunnel_build_state(struct seg6_local_lwt *slwt, const void *cfg,
2399 struct netlink_ext_ack *extack)
2400{
2401 struct seg6_action_desc *desc = slwt->desc;
2402 struct seg6_local_lwtunnel_ops *ops;
2403
2404 ops = &desc->slwt_ops;
2405 if (!ops->build_state)
2406 return 0;
2407
2408 return ops->build_state(slwt, cfg, extack);
2409}
2410
2411/* call the custom destructor of the behavior which is invoked before the
2412 * tunnel is going to be destroyed.
2413 */
2414static void seg6_local_lwtunnel_destroy_state(struct seg6_local_lwt *slwt)
2415{
2416 struct seg6_action_desc *desc = slwt->desc;
2417 struct seg6_local_lwtunnel_ops *ops;
2418
2419 ops = &desc->slwt_ops;
2420 if (!ops->destroy_state)
2421 return;
2422
2423 ops->destroy_state(slwt);
2424}
2425
2426static int parse_nla_action(struct nlattr **attrs, struct seg6_local_lwt *slwt,
2427 struct netlink_ext_ack *extack)
2428{
2429 struct seg6_action_param *param;
2430 struct seg6_action_desc *desc;
2431 unsigned long invalid_attrs;
2432 int i, err;
2433
2434 desc = __get_action_desc(slwt->action);
2435 if (!desc)
2436 return -EINVAL;
2437
2438 if (!desc->input)
2439 return -EOPNOTSUPP;
2440
2441 slwt->desc = desc;
2442 slwt->headroom += desc->static_headroom;
2443
2444 /* Forcing the desc->optattrs *set* and the desc->attrs *set* to be
2445 * disjoined, this allow us to release acquired resources by optional
2446 * attributes and by required attributes independently from each other
2447 * without any interference.
2448 * In other terms, we are sure that we do not release some the acquired
2449 * resources twice.
2450 *
2451 * Note that if an attribute is configured both as required and as
2452 * optional, it means that the user has messed something up in the
2453 * seg6_action_table. Therefore, this check is required for SRv6
2454 * behaviors to work properly.
2455 */
2456 invalid_attrs = desc->attrs & desc->optattrs;
2457 if (invalid_attrs) {
2458 WARN_ONCE(1,
2459 "An attribute cannot be both required AND optional");
2460 return -EINVAL;
2461 }
2462
2463 /* parse the required attributes */
2464 for (i = SEG6_LOCAL_SRH; i < SEG6_LOCAL_MAX + 1; i++) {
2465 if (desc->attrs & SEG6_F_ATTR(i)) {
2466 if (!attrs[i])
2467 return -EINVAL;
2468
2469 param = &seg6_action_params[i];
2470
2471 err = param->parse(attrs, slwt, extack);
2472 if (err < 0)
2473 goto parse_attrs_err;
2474 }
2475 }
2476
2477 /* parse the optional attributes, if any */
2478 err = parse_nla_optional_attrs(attrs, slwt, extack);
2479 if (err < 0)
2480 goto parse_attrs_err;
2481
2482 return 0;
2483
2484parse_attrs_err:
2485 /* release any resource that may have been acquired during the i-1
2486 * parse() operations.
2487 */
2488 __destroy_attrs(desc->attrs, i, slwt);
2489
2490 return err;
2491}
2492
2493static int seg6_local_build_state(struct net *net, struct nlattr *nla,
2494 unsigned int family, const void *cfg,
2495 struct lwtunnel_state **ts,
2496 struct netlink_ext_ack *extack)
2497{
2498 struct nlattr *tb[SEG6_LOCAL_MAX + 1];
2499 struct lwtunnel_state *newts;
2500 struct seg6_local_lwt *slwt;
2501 int err;
2502
2503 if (family != AF_INET6)
2504 return -EINVAL;
2505
2506 err = nla_parse_nested_deprecated(tb, SEG6_LOCAL_MAX, nla,
2507 seg6_local_policy, extack);
2508
2509 if (err < 0)
2510 return err;
2511
2512 if (!tb[SEG6_LOCAL_ACTION])
2513 return -EINVAL;
2514
2515 newts = lwtunnel_state_alloc(sizeof(*slwt));
2516 if (!newts)
2517 return -ENOMEM;
2518
2519 slwt = seg6_local_lwtunnel(newts);
2520 slwt->action = nla_get_u32(tb[SEG6_LOCAL_ACTION]);
2521
2522 err = parse_nla_action(tb, slwt, extack);
2523 if (err < 0)
2524 goto out_free;
2525
2526 err = seg6_local_lwtunnel_build_state(slwt, cfg, extack);
2527 if (err < 0)
2528 goto out_destroy_attrs;
2529
2530 newts->type = LWTUNNEL_ENCAP_SEG6_LOCAL;
2531 newts->flags = LWTUNNEL_STATE_INPUT_REDIRECT;
2532 newts->headroom = slwt->headroom;
2533
2534 *ts = newts;
2535
2536 return 0;
2537
2538out_destroy_attrs:
2539 destroy_attrs(slwt);
2540out_free:
2541 kfree(newts);
2542 return err;
2543}
2544
2545static void seg6_local_destroy_state(struct lwtunnel_state *lwt)
2546{
2547 struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
2548
2549 seg6_local_lwtunnel_destroy_state(slwt);
2550
2551 destroy_attrs(slwt);
2552
2553 return;
2554}
2555
2556static int seg6_local_fill_encap(struct sk_buff *skb,
2557 struct lwtunnel_state *lwt)
2558{
2559 struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
2560 struct seg6_action_param *param;
2561 unsigned long attrs;
2562 int i, err;
2563
2564 if (nla_put_u32(skb, SEG6_LOCAL_ACTION, slwt->action))
2565 return -EMSGSIZE;
2566
2567 attrs = slwt->desc->attrs | slwt->parsed_optattrs;
2568
2569 for (i = SEG6_LOCAL_SRH; i < SEG6_LOCAL_MAX + 1; i++) {
2570 if (attrs & SEG6_F_ATTR(i)) {
2571 param = &seg6_action_params[i];
2572 err = param->put(skb, slwt);
2573 if (err < 0)
2574 return err;
2575 }
2576 }
2577
2578 return 0;
2579}
2580
2581static int seg6_local_get_encap_size(struct lwtunnel_state *lwt)
2582{
2583 struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
2584 unsigned long attrs;
2585 int nlsize;
2586
2587 nlsize = nla_total_size(4); /* action */
2588
2589 attrs = slwt->desc->attrs | slwt->parsed_optattrs;
2590
2591 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_SRH))
2592 nlsize += nla_total_size((slwt->srh->hdrlen + 1) << 3);
2593
2594 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_TABLE))
2595 nlsize += nla_total_size(4);
2596
2597 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_NH4))
2598 nlsize += nla_total_size(4);
2599
2600 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_NH6))
2601 nlsize += nla_total_size(16);
2602
2603 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_IIF))
2604 nlsize += nla_total_size(4);
2605
2606 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_OIF))
2607 nlsize += nla_total_size(4);
2608
2609 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_BPF))
2610 nlsize += nla_total_size(sizeof(struct nlattr)) +
2611 nla_total_size(MAX_PROG_NAME) +
2612 nla_total_size(4);
2613
2614 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_VRFTABLE))
2615 nlsize += nla_total_size(4);
2616
2617 if (attrs & SEG6_F_LOCAL_COUNTERS)
2618 nlsize += nla_total_size(0) + /* nest SEG6_LOCAL_COUNTERS */
2619 /* SEG6_LOCAL_CNT_PACKETS */
2620 nla_total_size_64bit(sizeof(__u64)) +
2621 /* SEG6_LOCAL_CNT_BYTES */
2622 nla_total_size_64bit(sizeof(__u64)) +
2623 /* SEG6_LOCAL_CNT_ERRORS */
2624 nla_total_size_64bit(sizeof(__u64));
2625
2626 if (attrs & SEG6_F_ATTR(SEG6_LOCAL_FLAVORS))
2627 nlsize += encap_size_flavors(slwt);
2628
2629 return nlsize;
2630}
2631
2632static int seg6_local_cmp_encap(struct lwtunnel_state *a,
2633 struct lwtunnel_state *b)
2634{
2635 struct seg6_local_lwt *slwt_a, *slwt_b;
2636 struct seg6_action_param *param;
2637 unsigned long attrs_a, attrs_b;
2638 int i;
2639
2640 slwt_a = seg6_local_lwtunnel(a);
2641 slwt_b = seg6_local_lwtunnel(b);
2642
2643 if (slwt_a->action != slwt_b->action)
2644 return 1;
2645
2646 attrs_a = slwt_a->desc->attrs | slwt_a->parsed_optattrs;
2647 attrs_b = slwt_b->desc->attrs | slwt_b->parsed_optattrs;
2648
2649 if (attrs_a != attrs_b)
2650 return 1;
2651
2652 for (i = SEG6_LOCAL_SRH; i < SEG6_LOCAL_MAX + 1; i++) {
2653 if (attrs_a & SEG6_F_ATTR(i)) {
2654 param = &seg6_action_params[i];
2655 if (param->cmp(slwt_a, slwt_b))
2656 return 1;
2657 }
2658 }
2659
2660 return 0;
2661}
2662
2663static const struct lwtunnel_encap_ops seg6_local_ops = {
2664 .build_state = seg6_local_build_state,
2665 .destroy_state = seg6_local_destroy_state,
2666 .input = seg6_local_input,
2667 .fill_encap = seg6_local_fill_encap,
2668 .get_encap_size = seg6_local_get_encap_size,
2669 .cmp_encap = seg6_local_cmp_encap,
2670 .owner = THIS_MODULE,
2671};
2672
2673int __init seg6_local_init(void)
2674{
2675 /* If the max total number of defined attributes is reached, then your
2676 * kernel build stops here.
2677 *
2678 * This check is required to avoid arithmetic overflows when processing
2679 * behavior attributes and the maximum number of defined attributes
2680 * exceeds the allowed value.
2681 */
2682 BUILD_BUG_ON(SEG6_LOCAL_MAX + 1 > BITS_PER_TYPE(unsigned long));
2683
2684 /* Check whether the number of defined flavors exceeds the maximum
2685 * allowed value.
2686 */
2687 BUILD_BUG_ON(SEG6_LOCAL_FLV_OP_MAX + 1 > BITS_PER_TYPE(__u32));
2688
2689 /* If the default NEXT-C-SID Locator-Block/Node Function lengths (in
2690 * bits) have been changed with invalid values, kernel build stops
2691 * here.
2692 */
2693 BUILD_BUG_ON(next_csid_chk_cntr_bits(SEG6_LOCAL_LCBLOCK_DBITS,
2694 SEG6_LOCAL_LCNODE_FN_DBITS));
2695 BUILD_BUG_ON(next_csid_chk_lcblock_bits(SEG6_LOCAL_LCBLOCK_DBITS));
2696 BUILD_BUG_ON(next_csid_chk_lcnode_fn_bits(SEG6_LOCAL_LCNODE_FN_DBITS));
2697
2698 /* To be memory efficient, we use 'u8' to represent the different
2699 * actions related to RFC8986 flavors. If the kernel build stops here,
2700 * it means that it is not possible to correctly encode these actions
2701 * with the data type chosen for the action table.
2702 */
2703 BUILD_BUG_ON(SEG6_LOCAL_FLV_ACT_MAX > (typeof(flv8986_act_tbl[0]))~0U);
2704
2705 return lwtunnel_encap_add_ops(&seg6_local_ops,
2706 LWTUNNEL_ENCAP_SEG6_LOCAL);
2707}
2708
2709void seg6_local_exit(void)
2710{
2711 lwtunnel_encap_del_ops(&seg6_local_ops, LWTUNNEL_ENCAP_SEG6_LOCAL);
2712}