1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
4 * Copyright (c) 2014 Intel Corporation
5 * Author: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
6 *
7 * Development of this code funded by Astaro AG (http://www.astaro.com/)
8 */
9
10#include <linux/kernel.h>
11#include <linux/netlink.h>
12#include <linux/netfilter.h>
13#include <linux/netfilter/nf_tables.h>
14#include <linux/in.h>
15#include <linux/ip.h>
16#include <linux/ipv6.h>
17#include <linux/random.h>
18#include <linux/smp.h>
19#include <linux/static_key.h>
20#include <net/dst.h>
21#include <net/ip.h>
22#include <net/sock.h>
23#include <net/tcp_states.h> /* for TCP_TIME_WAIT */
24#include <net/netfilter/nf_tables.h>
25#include <net/netfilter/nf_tables_core.h>
26#include <net/netfilter/nft_meta.h>
27#include <net/netfilter/nf_tables_offload.h>
28
29#include <uapi/linux/netfilter_bridge.h> /* NF_BR_PRE_ROUTING */
30
31#define NFT_META_SECS_PER_MINUTE 60
32#define NFT_META_SECS_PER_HOUR 3600
33#define NFT_META_SECS_PER_DAY 86400
34#define NFT_META_DAYS_PER_WEEK 7
35
36static u8 nft_meta_weekday(void)
37{
38 time64_t secs = ktime_get_real_seconds();
39 unsigned int dse;
40 u8 wday;
41
42 secs -= NFT_META_SECS_PER_MINUTE * sys_tz.tz_minuteswest;
43 dse = div_u64(dividend: secs, NFT_META_SECS_PER_DAY);
44 wday = (4 + dse) % NFT_META_DAYS_PER_WEEK;
45
46 return wday;
47}
48
49static u32 nft_meta_hour(time64_t secs)
50{
51 struct tm tm;
52
53 time64_to_tm(totalsecs: secs, offset: 0, result: &tm);
54
55 return tm.tm_hour * NFT_META_SECS_PER_HOUR
56 + tm.tm_min * NFT_META_SECS_PER_MINUTE
57 + tm.tm_sec;
58}
59
60static noinline_for_stack void
61nft_meta_get_eval_time(enum nft_meta_keys key,
62 u32 *dest)
63{
64 switch (key) {
65 case NFT_META_TIME_NS:
66 nft_reg_store64(dreg: dest, val: ktime_get_real_ns());
67 break;
68 case NFT_META_TIME_DAY:
69 nft_reg_store8(dreg: dest, val: nft_meta_weekday());
70 break;
71 case NFT_META_TIME_HOUR:
72 *dest = nft_meta_hour(secs: ktime_get_real_seconds());
73 break;
74 default:
75 break;
76 }
77}
78
79static noinline bool
80nft_meta_get_eval_pkttype_lo(const struct nft_pktinfo *pkt,
81 u32 *dest)
82{
83 const struct sk_buff *skb = pkt->skb;
84
85 switch (nft_pf(pkt)) {
86 case NFPROTO_IPV4:
87 if (ipv4_is_multicast(addr: ip_hdr(skb)->daddr))
88 nft_reg_store8(dreg: dest, PACKET_MULTICAST);
89 else
90 nft_reg_store8(dreg: dest, PACKET_BROADCAST);
91 break;
92 case NFPROTO_IPV6:
93 nft_reg_store8(dreg: dest, PACKET_MULTICAST);
94 break;
95 case NFPROTO_NETDEV:
96 switch (skb->protocol) {
97 case htons(ETH_P_IP): {
98 int noff = skb_network_offset(skb);
99 struct iphdr *iph, _iph;
100
101 iph = skb_header_pointer(skb, offset: noff,
102 len: sizeof(_iph), buffer: &_iph);
103 if (!iph)
104 return false;
105
106 if (ipv4_is_multicast(addr: iph->daddr))
107 nft_reg_store8(dreg: dest, PACKET_MULTICAST);
108 else
109 nft_reg_store8(dreg: dest, PACKET_BROADCAST);
110
111 break;
112 }
113 case htons(ETH_P_IPV6):
114 nft_reg_store8(dreg: dest, PACKET_MULTICAST);
115 break;
116 default:
117 WARN_ON_ONCE(1);
118 return false;
119 }
120 break;
121 default:
122 WARN_ON_ONCE(1);
123 return false;
124 }
125
126 return true;
127}
128
129static noinline bool
130nft_meta_get_eval_skugid(enum nft_meta_keys key,
131 u32 *dest,
132 const struct nft_pktinfo *pkt)
133{
134 struct sock *sk = skb_to_full_sk(skb: pkt->skb);
135 struct socket *sock;
136
137 if (!sk || !sk_fullsock(sk) || !net_eq(net1: nft_net(pkt), net2: sock_net(sk)))
138 return false;
139
140 read_lock_bh(&sk->sk_callback_lock);
141 sock = sk->sk_socket;
142 if (!sock || !sock->file) {
143 read_unlock_bh(&sk->sk_callback_lock);
144 return false;
145 }
146
147 switch (key) {
148 case NFT_META_SKUID:
149 *dest = from_kuid_munged(to: sock_net(sk)->user_ns,
150 uid: sock->file->f_cred->fsuid);
151 break;
152 case NFT_META_SKGID:
153 *dest = from_kgid_munged(to: sock_net(sk)->user_ns,
154 gid: sock->file->f_cred->fsgid);
155 break;
156 default:
157 break;
158 }
159
160 read_unlock_bh(&sk->sk_callback_lock);
161 return true;
162}
163
164#ifdef CONFIG_CGROUP_NET_CLASSID
165static noinline bool
166nft_meta_get_eval_cgroup(u32 *dest, const struct nft_pktinfo *pkt)
167{
168 struct sock *sk = skb_to_full_sk(skb: pkt->skb);
169
170 if (!sk || !sk_fullsock(sk) || !net_eq(net1: nft_net(pkt), net2: sock_net(sk)))
171 return false;
172
173 *dest = sock_cgroup_classid(skcd: &sk->sk_cgrp_data);
174 return true;
175}
176#endif
177
178static noinline bool nft_meta_get_eval_kind(enum nft_meta_keys key,
179 u32 *dest,
180 const struct nft_pktinfo *pkt)
181{
182 const struct net_device *in = nft_in(pkt), *out = nft_out(pkt);
183
184 switch (key) {
185 case NFT_META_IIFKIND:
186 if (!in || !in->rtnl_link_ops)
187 return false;
188 strscpy_pad(dest: (char *)dest, src: in->rtnl_link_ops->kind, IFNAMSIZ);
189 break;
190 case NFT_META_OIFKIND:
191 if (!out || !out->rtnl_link_ops)
192 return false;
193 strscpy_pad(dest: (char *)dest, src: out->rtnl_link_ops->kind, IFNAMSIZ);
194 break;
195 default:
196 return false;
197 }
198
199 return true;
200}
201
202static void nft_meta_store_ifindex(u32 *dest, const struct net_device *dev)
203{
204 *dest = dev ? dev->ifindex : 0;
205}
206
207static void nft_meta_store_ifname(u32 *dest, const struct net_device *dev)
208{
209 strscpy_pad(dest: (char *)dest, src: dev ? dev->name : "", IFNAMSIZ);
210}
211
212static bool nft_meta_store_iftype(u32 *dest, const struct net_device *dev)
213{
214 if (!dev)
215 return false;
216
217 nft_reg_store16(dreg: dest, val: dev->type);
218 return true;
219}
220
221static bool nft_meta_store_ifgroup(u32 *dest, const struct net_device *dev)
222{
223 if (!dev)
224 return false;
225
226 *dest = dev->group;
227 return true;
228}
229
230static bool nft_meta_get_eval_ifname(enum nft_meta_keys key, u32 *dest,
231 const struct nft_pktinfo *pkt)
232{
233 switch (key) {
234 case NFT_META_IIFNAME:
235 nft_meta_store_ifname(dest, dev: nft_in(pkt));
236 break;
237 case NFT_META_OIFNAME:
238 nft_meta_store_ifname(dest, dev: nft_out(pkt));
239 break;
240 case NFT_META_IIF:
241 nft_meta_store_ifindex(dest, dev: nft_in(pkt));
242 break;
243 case NFT_META_OIF:
244 nft_meta_store_ifindex(dest, dev: nft_out(pkt));
245 break;
246 case NFT_META_IFTYPE:
247 if (!nft_meta_store_iftype(dest, dev: pkt->skb->dev))
248 return false;
249 break;
250 case __NFT_META_IIFTYPE:
251 if (!nft_meta_store_iftype(dest, dev: nft_in(pkt)))
252 return false;
253 break;
254 case NFT_META_OIFTYPE:
255 if (!nft_meta_store_iftype(dest, dev: nft_out(pkt)))
256 return false;
257 break;
258 case NFT_META_IIFGROUP:
259 if (!nft_meta_store_ifgroup(dest, dev: nft_in(pkt)))
260 return false;
261 break;
262 case NFT_META_OIFGROUP:
263 if (!nft_meta_store_ifgroup(dest, dev: nft_out(pkt)))
264 return false;
265 break;
266 default:
267 return false;
268 }
269
270 return true;
271}
272
273#ifdef CONFIG_IP_ROUTE_CLASSID
274static noinline bool
275nft_meta_get_eval_rtclassid(const struct sk_buff *skb, u32 *dest)
276{
277 const struct dst_entry *dst = skb_dst(skb);
278
279 if (!dst)
280 return false;
281
282 *dest = dst->tclassid;
283 return true;
284}
285#endif
286
287static noinline u32 nft_meta_get_eval_sdif(const struct nft_pktinfo *pkt)
288{
289 switch (nft_pf(pkt)) {
290 case NFPROTO_IPV4:
291 return inet_sdif(skb: pkt->skb);
292 case NFPROTO_IPV6:
293 return inet6_sdif(skb: pkt->skb);
294 }
295
296 return 0;
297}
298
299static noinline void
300nft_meta_get_eval_sdifname(u32 *dest, const struct nft_pktinfo *pkt)
301{
302 u32 sdif = nft_meta_get_eval_sdif(pkt);
303 const struct net_device *dev;
304
305 dev = sdif ? dev_get_by_index_rcu(net: nft_net(pkt), ifindex: sdif) : NULL;
306 nft_meta_store_ifname(dest, dev);
307}
308
309void nft_meta_get_eval(const struct nft_expr *expr,
310 struct nft_regs *regs,
311 const struct nft_pktinfo *pkt)
312{
313 const struct nft_meta *priv = nft_expr_priv(expr);
314 const struct sk_buff *skb = pkt->skb;
315 u32 *dest = &regs->data[priv->dreg];
316
317 switch (priv->key) {
318 case NFT_META_LEN:
319 *dest = skb->len;
320 break;
321 case NFT_META_PROTOCOL:
322 nft_reg_store16(dreg: dest, val: (__force u16)skb->protocol);
323 break;
324 case NFT_META_NFPROTO:
325 nft_reg_store8(dreg: dest, val: nft_pf(pkt));
326 break;
327 case NFT_META_L4PROTO:
328 if (!(pkt->flags & NFT_PKTINFO_L4PROTO))
329 goto err;
330 nft_reg_store8(dreg: dest, val: pkt->tprot);
331 break;
332 case NFT_META_PRIORITY:
333 *dest = skb->priority;
334 break;
335 case NFT_META_MARK:
336 *dest = skb->mark;
337 break;
338 case NFT_META_IIF:
339 case NFT_META_OIF:
340 case NFT_META_IIFNAME:
341 case NFT_META_OIFNAME:
342 case NFT_META_IIFTYPE:
343 case NFT_META_OIFTYPE:
344 case NFT_META_IIFGROUP:
345 case NFT_META_OIFGROUP:
346 if (!nft_meta_get_eval_ifname(key: priv->key, dest, pkt))
347 goto err;
348 break;
349 case NFT_META_SKUID:
350 case NFT_META_SKGID:
351 if (!nft_meta_get_eval_skugid(key: priv->key, dest, pkt))
352 goto err;
353 break;
354#ifdef CONFIG_IP_ROUTE_CLASSID
355 case NFT_META_RTCLASSID:
356 if (!nft_meta_get_eval_rtclassid(skb, dest))
357 goto err;
358 break;
359#endif
360#ifdef CONFIG_NETWORK_SECMARK
361 case NFT_META_SECMARK:
362 *dest = skb->secmark;
363 break;
364#endif
365 case NFT_META_PKTTYPE:
366 if (skb->pkt_type != PACKET_LOOPBACK) {
367 nft_reg_store8(dreg: dest, val: skb->pkt_type);
368 break;
369 }
370
371 if (!nft_meta_get_eval_pkttype_lo(pkt, dest))
372 goto err;
373 break;
374 case NFT_META_CPU:
375 *dest = raw_smp_processor_id();
376 break;
377#ifdef CONFIG_CGROUP_NET_CLASSID
378 case NFT_META_CGROUP:
379 if (!nft_meta_get_eval_cgroup(dest, pkt))
380 goto err;
381 break;
382#endif
383 case NFT_META_PRANDOM:
384 *dest = get_random_u32();
385 break;
386#ifdef CONFIG_XFRM
387 case NFT_META_SECPATH:
388 nft_reg_store8(dreg: dest, val: secpath_exists(skb));
389 break;
390#endif
391 case NFT_META_IIFKIND:
392 case NFT_META_OIFKIND:
393 if (!nft_meta_get_eval_kind(key: priv->key, dest, pkt))
394 goto err;
395 break;
396 case NFT_META_TIME_NS:
397 case NFT_META_TIME_DAY:
398 case NFT_META_TIME_HOUR:
399 nft_meta_get_eval_time(key: priv->key, dest);
400 break;
401 case NFT_META_SDIF:
402 *dest = nft_meta_get_eval_sdif(pkt);
403 break;
404 case NFT_META_SDIFNAME:
405 nft_meta_get_eval_sdifname(dest, pkt);
406 break;
407 default:
408 WARN_ON(1);
409 goto err;
410 }
411 return;
412
413err:
414 regs->verdict.code = NFT_BREAK;
415}
416EXPORT_SYMBOL_GPL(nft_meta_get_eval);
417
418void nft_meta_set_eval(const struct nft_expr *expr,
419 struct nft_regs *regs,
420 const struct nft_pktinfo *pkt)
421{
422 const struct nft_meta *meta = nft_expr_priv(expr);
423 struct sk_buff *skb = pkt->skb;
424 u32 *sreg = &regs->data[meta->sreg];
425 u32 value = *sreg;
426 u8 value8;
427
428 switch (meta->key) {
429 case NFT_META_MARK:
430 skb->mark = value;
431 break;
432 case NFT_META_PRIORITY:
433 skb->priority = value;
434 break;
435 case NFT_META_PKTTYPE:
436 value8 = nft_reg_load8(sreg);
437
438 if (skb->pkt_type != value8 &&
439 skb_pkt_type_ok(ptype: value8) &&
440 skb_pkt_type_ok(ptype: skb->pkt_type))
441 skb->pkt_type = value8;
442 break;
443 case NFT_META_NFTRACE:
444 value8 = nft_reg_load8(sreg);
445
446 skb->nf_trace = !!value8;
447 break;
448#ifdef CONFIG_NETWORK_SECMARK
449 case NFT_META_SECMARK:
450 skb->secmark = value;
451 break;
452#endif
453 default:
454 WARN_ON(1);
455 }
456}
457EXPORT_SYMBOL_GPL(nft_meta_set_eval);
458
459const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = {
460 [NFTA_META_DREG] = { .type = NLA_U32 },
461 [NFTA_META_KEY] = NLA_POLICY_MAX(NLA_BE32, 255),
462 [NFTA_META_SREG] = { .type = NLA_U32 },
463};
464EXPORT_SYMBOL_GPL(nft_meta_policy);
465
466int nft_meta_get_init(const struct nft_ctx *ctx,
467 const struct nft_expr *expr,
468 const struct nlattr * const tb[])
469{
470 struct nft_meta *priv = nft_expr_priv(expr);
471 unsigned int len;
472
473 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
474 switch (priv->key) {
475 case NFT_META_PROTOCOL:
476 case NFT_META_IIFTYPE:
477 case NFT_META_OIFTYPE:
478 len = sizeof(u16);
479 break;
480 case NFT_META_NFPROTO:
481 case NFT_META_L4PROTO:
482 case NFT_META_LEN:
483 case NFT_META_PRIORITY:
484 case NFT_META_MARK:
485 case NFT_META_IIF:
486 case NFT_META_OIF:
487 case NFT_META_SDIF:
488 case NFT_META_SKUID:
489 case NFT_META_SKGID:
490#ifdef CONFIG_IP_ROUTE_CLASSID
491 case NFT_META_RTCLASSID:
492#endif
493#ifdef CONFIG_NETWORK_SECMARK
494 case NFT_META_SECMARK:
495#endif
496 case NFT_META_PKTTYPE:
497 case NFT_META_CPU:
498 case NFT_META_IIFGROUP:
499 case NFT_META_OIFGROUP:
500#ifdef CONFIG_CGROUP_NET_CLASSID
501 case NFT_META_CGROUP:
502#endif
503 len = sizeof(u32);
504 break;
505 case NFT_META_IIFNAME:
506 case NFT_META_OIFNAME:
507 case NFT_META_IIFKIND:
508 case NFT_META_OIFKIND:
509 case NFT_META_SDIFNAME:
510 len = IFNAMSIZ;
511 break;
512 case NFT_META_PRANDOM:
513 len = sizeof(u32);
514 break;
515#ifdef CONFIG_XFRM
516 case NFT_META_SECPATH:
517 len = sizeof(u8);
518 break;
519#endif
520 case NFT_META_TIME_NS:
521 len = sizeof(u64);
522 break;
523 case NFT_META_TIME_DAY:
524 len = sizeof(u8);
525 break;
526 case NFT_META_TIME_HOUR:
527 len = sizeof(u32);
528 break;
529 default:
530 return -EOPNOTSUPP;
531 }
532
533 priv->len = len;
534 return nft_parse_register_store(ctx, attr: tb[NFTA_META_DREG], dreg: &priv->dreg,
535 NULL, type: NFT_DATA_VALUE, len);
536}
537EXPORT_SYMBOL_GPL(nft_meta_get_init);
538
539static int nft_meta_get_validate_sdif(const struct nft_ctx *ctx)
540{
541 unsigned int hooks;
542
543 switch (ctx->family) {
544 case NFPROTO_IPV4:
545 case NFPROTO_IPV6:
546 case NFPROTO_INET:
547 hooks = (1 << NF_INET_LOCAL_IN) |
548 (1 << NF_INET_FORWARD);
549 break;
550 default:
551 return -EOPNOTSUPP;
552 }
553
554 return nft_chain_validate_hooks(chain: ctx->chain, hook_flags: hooks);
555}
556
557static int nft_meta_get_validate_xfrm(const struct nft_ctx *ctx)
558{
559#ifdef CONFIG_XFRM
560 unsigned int hooks;
561
562 switch (ctx->family) {
563 case NFPROTO_NETDEV:
564 hooks = 1 << NF_NETDEV_INGRESS;
565 break;
566 case NFPROTO_IPV4:
567 case NFPROTO_IPV6:
568 case NFPROTO_INET:
569 hooks = (1 << NF_INET_PRE_ROUTING) |
570 (1 << NF_INET_LOCAL_IN) |
571 (1 << NF_INET_FORWARD);
572 break;
573 default:
574 return -EOPNOTSUPP;
575 }
576
577 return nft_chain_validate_hooks(chain: ctx->chain, hook_flags: hooks);
578#else
579 return 0;
580#endif
581}
582
583static int nft_meta_get_validate(const struct nft_ctx *ctx,
584 const struct nft_expr *expr,
585 const struct nft_data **data)
586{
587 const struct nft_meta *priv = nft_expr_priv(expr);
588
589 switch (priv->key) {
590 case NFT_META_SECPATH:
591 return nft_meta_get_validate_xfrm(ctx);
592 case NFT_META_SDIF:
593 case NFT_META_SDIFNAME:
594 return nft_meta_get_validate_sdif(ctx);
595 default:
596 break;
597 }
598
599 return 0;
600}
601
602int nft_meta_set_validate(const struct nft_ctx *ctx,
603 const struct nft_expr *expr,
604 const struct nft_data **data)
605{
606 struct nft_meta *priv = nft_expr_priv(expr);
607 unsigned int hooks;
608
609 if (priv->key != NFT_META_PKTTYPE)
610 return 0;
611
612 switch (ctx->family) {
613 case NFPROTO_BRIDGE:
614 hooks = 1 << NF_BR_PRE_ROUTING;
615 break;
616 case NFPROTO_NETDEV:
617 hooks = 1 << NF_NETDEV_INGRESS;
618 break;
619 case NFPROTO_IPV4:
620 case NFPROTO_IPV6:
621 case NFPROTO_INET:
622 hooks = 1 << NF_INET_PRE_ROUTING;
623 break;
624 default:
625 return -EOPNOTSUPP;
626 }
627
628 return nft_chain_validate_hooks(chain: ctx->chain, hook_flags: hooks);
629}
630EXPORT_SYMBOL_GPL(nft_meta_set_validate);
631
632int nft_meta_set_init(const struct nft_ctx *ctx,
633 const struct nft_expr *expr,
634 const struct nlattr * const tb[])
635{
636 struct nft_meta *priv = nft_expr_priv(expr);
637 unsigned int len;
638 int err;
639
640 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
641 switch (priv->key) {
642 case NFT_META_MARK:
643 case NFT_META_PRIORITY:
644#ifdef CONFIG_NETWORK_SECMARK
645 case NFT_META_SECMARK:
646#endif
647 len = sizeof(u32);
648 break;
649 case NFT_META_NFTRACE:
650 len = sizeof(u8);
651 break;
652 case NFT_META_PKTTYPE:
653 len = sizeof(u8);
654 break;
655 default:
656 return -EOPNOTSUPP;
657 }
658
659 priv->len = len;
660 err = nft_parse_register_load(attr: tb[NFTA_META_SREG], sreg: &priv->sreg, len);
661 if (err < 0)
662 return err;
663
664 if (priv->key == NFT_META_NFTRACE)
665 static_branch_inc(&nft_trace_enabled);
666
667 return 0;
668}
669EXPORT_SYMBOL_GPL(nft_meta_set_init);
670
671int nft_meta_get_dump(struct sk_buff *skb,
672 const struct nft_expr *expr, bool reset)
673{
674 const struct nft_meta *priv = nft_expr_priv(expr);
675
676 if (nla_put_be32(skb, attrtype: NFTA_META_KEY, htonl(priv->key)))
677 goto nla_put_failure;
678 if (nft_dump_register(skb, attr: NFTA_META_DREG, reg: priv->dreg))
679 goto nla_put_failure;
680 return 0;
681
682nla_put_failure:
683 return -1;
684}
685EXPORT_SYMBOL_GPL(nft_meta_get_dump);
686
687int nft_meta_set_dump(struct sk_buff *skb,
688 const struct nft_expr *expr, bool reset)
689{
690 const struct nft_meta *priv = nft_expr_priv(expr);
691
692 if (nla_put_be32(skb, attrtype: NFTA_META_KEY, htonl(priv->key)))
693 goto nla_put_failure;
694 if (nft_dump_register(skb, attr: NFTA_META_SREG, reg: priv->sreg))
695 goto nla_put_failure;
696
697 return 0;
698
699nla_put_failure:
700 return -1;
701}
702EXPORT_SYMBOL_GPL(nft_meta_set_dump);
703
704void nft_meta_set_destroy(const struct nft_ctx *ctx,
705 const struct nft_expr *expr)
706{
707 const struct nft_meta *priv = nft_expr_priv(expr);
708
709 if (priv->key == NFT_META_NFTRACE)
710 static_branch_dec(&nft_trace_enabled);
711}
712EXPORT_SYMBOL_GPL(nft_meta_set_destroy);
713
714static int nft_meta_get_offload(struct nft_offload_ctx *ctx,
715 struct nft_flow_rule *flow,
716 const struct nft_expr *expr)
717{
718 const struct nft_meta *priv = nft_expr_priv(expr);
719 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
720
721 switch (priv->key) {
722 case NFT_META_PROTOCOL:
723 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, n_proto,
724 sizeof(__u16), reg);
725 nft_offload_set_dependency(ctx, type: NFT_OFFLOAD_DEP_NETWORK);
726 break;
727 case NFT_META_L4PROTO:
728 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
729 sizeof(__u8), reg);
730 nft_offload_set_dependency(ctx, type: NFT_OFFLOAD_DEP_TRANSPORT);
731 break;
732 case NFT_META_IIF:
733 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
734 ingress_ifindex, sizeof(__u32), reg);
735 break;
736 case NFT_META_IIFTYPE:
737 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
738 ingress_iftype, sizeof(__u16), reg);
739 break;
740 default:
741 return -EOPNOTSUPP;
742 }
743
744 return 0;
745}
746
747bool nft_meta_get_reduce(struct nft_regs_track *track,
748 const struct nft_expr *expr)
749{
750 const struct nft_meta *priv = nft_expr_priv(expr);
751 const struct nft_meta *meta;
752
753 if (!nft_reg_track_cmp(track, expr, dreg: priv->dreg)) {
754 nft_reg_track_update(track, expr, dreg: priv->dreg, len: priv->len);
755 return false;
756 }
757
758 meta = nft_expr_priv(expr: track->regs[priv->dreg].selector);
759 if (priv->key != meta->key ||
760 priv->dreg != meta->dreg) {
761 nft_reg_track_update(track, expr, dreg: priv->dreg, len: priv->len);
762 return false;
763 }
764
765 if (!track->regs[priv->dreg].bitwise)
766 return true;
767
768 return nft_expr_reduce_bitwise(track, expr);
769}
770EXPORT_SYMBOL_GPL(nft_meta_get_reduce);
771
772static const struct nft_expr_ops nft_meta_get_ops = {
773 .type = &nft_meta_type,
774 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
775 .eval = nft_meta_get_eval,
776 .init = nft_meta_get_init,
777 .dump = nft_meta_get_dump,
778 .reduce = nft_meta_get_reduce,
779 .validate = nft_meta_get_validate,
780 .offload = nft_meta_get_offload,
781};
782
783static bool nft_meta_set_reduce(struct nft_regs_track *track,
784 const struct nft_expr *expr)
785{
786 int i;
787
788 for (i = 0; i < NFT_REG32_NUM; i++) {
789 if (!track->regs[i].selector)
790 continue;
791
792 if (track->regs[i].selector->ops != &nft_meta_get_ops)
793 continue;
794
795 __nft_reg_track_cancel(track, dreg: i);
796 }
797
798 return false;
799}
800
801static const struct nft_expr_ops nft_meta_set_ops = {
802 .type = &nft_meta_type,
803 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
804 .eval = nft_meta_set_eval,
805 .init = nft_meta_set_init,
806 .destroy = nft_meta_set_destroy,
807 .dump = nft_meta_set_dump,
808 .reduce = nft_meta_set_reduce,
809 .validate = nft_meta_set_validate,
810};
811
812static const struct nft_expr_ops *
813nft_meta_select_ops(const struct nft_ctx *ctx,
814 const struct nlattr * const tb[])
815{
816 if (tb[NFTA_META_KEY] == NULL)
817 return ERR_PTR(error: -EINVAL);
818
819 if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
820 return ERR_PTR(error: -EINVAL);
821
822#if IS_ENABLED(CONFIG_NF_TABLES_BRIDGE) && IS_MODULE(CONFIG_NFT_BRIDGE_META)
823 if (ctx->family == NFPROTO_BRIDGE)
824 return ERR_PTR(-EAGAIN);
825#endif
826 if (tb[NFTA_META_DREG])
827 return &nft_meta_get_ops;
828
829 if (tb[NFTA_META_SREG])
830 return &nft_meta_set_ops;
831
832 return ERR_PTR(error: -EINVAL);
833}
834
835static int nft_meta_inner_init(const struct nft_ctx *ctx,
836 const struct nft_expr *expr,
837 const struct nlattr * const tb[])
838{
839 struct nft_meta *priv = nft_expr_priv(expr);
840 unsigned int len;
841
842 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
843 switch (priv->key) {
844 case NFT_META_PROTOCOL:
845 len = sizeof(u16);
846 break;
847 case NFT_META_L4PROTO:
848 len = sizeof(u32);
849 break;
850 default:
851 return -EOPNOTSUPP;
852 }
853 priv->len = len;
854
855 return nft_parse_register_store(ctx, attr: tb[NFTA_META_DREG], dreg: &priv->dreg,
856 NULL, type: NFT_DATA_VALUE, len);
857}
858
859void nft_meta_inner_eval(const struct nft_expr *expr,
860 struct nft_regs *regs,
861 const struct nft_pktinfo *pkt,
862 struct nft_inner_tun_ctx *tun_ctx)
863{
864 const struct nft_meta *priv = nft_expr_priv(expr);
865 u32 *dest = &regs->data[priv->dreg];
866
867 switch (priv->key) {
868 case NFT_META_PROTOCOL:
869 nft_reg_store16(dreg: dest, val: (__force u16)tun_ctx->llproto);
870 break;
871 case NFT_META_L4PROTO:
872 if (!(tun_ctx->flags & NFT_PAYLOAD_CTX_INNER_TH))
873 goto err;
874
875 nft_reg_store8(dreg: dest, val: tun_ctx->l4proto);
876 break;
877 default:
878 WARN_ON_ONCE(1);
879 goto err;
880 }
881 return;
882
883err:
884 regs->verdict.code = NFT_BREAK;
885}
886EXPORT_SYMBOL_GPL(nft_meta_inner_eval);
887
888static const struct nft_expr_ops nft_meta_inner_ops = {
889 .type = &nft_meta_type,
890 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
891 .init = nft_meta_inner_init,
892 .dump = nft_meta_get_dump,
893 /* direct call to nft_meta_inner_eval(). */
894};
895
896struct nft_expr_type nft_meta_type __read_mostly = {
897 .name = "meta",
898 .select_ops = nft_meta_select_ops,
899 .inner_ops = &nft_meta_inner_ops,
900 .policy = nft_meta_policy,
901 .maxattr = NFTA_META_MAX,
902 .owner = THIS_MODULE,
903};
904
905#ifdef CONFIG_NETWORK_SECMARK
906struct nft_secmark {
907 u32 secid;
908 char *ctx;
909};
910
911static const struct nla_policy nft_secmark_policy[NFTA_SECMARK_MAX + 1] = {
912 [NFTA_SECMARK_CTX] = { .type = NLA_STRING, .len = NFT_SECMARK_CTX_MAXLEN },
913};
914
915static int nft_secmark_compute_secid(struct nft_secmark *priv)
916{
917 u32 tmp_secid = 0;
918 int err;
919
920 err = security_secctx_to_secid(secdata: priv->ctx, strlen(priv->ctx), secid: &tmp_secid);
921 if (err)
922 return err;
923
924 if (!tmp_secid)
925 return -ENOENT;
926
927 err = security_secmark_relabel_packet(secid: tmp_secid);
928 if (err)
929 return err;
930
931 priv->secid = tmp_secid;
932 return 0;
933}
934
935static void nft_secmark_obj_eval(struct nft_object *obj, struct nft_regs *regs,
936 const struct nft_pktinfo *pkt)
937{
938 const struct nft_secmark *priv = nft_obj_data(obj);
939 struct sk_buff *skb = pkt->skb;
940
941 skb->secmark = priv->secid;
942}
943
944static int nft_secmark_obj_init(const struct nft_ctx *ctx,
945 const struct nlattr * const tb[],
946 struct nft_object *obj)
947{
948 struct nft_secmark *priv = nft_obj_data(obj);
949 int err;
950
951 if (tb[NFTA_SECMARK_CTX] == NULL)
952 return -EINVAL;
953
954 priv->ctx = nla_strdup(nla: tb[NFTA_SECMARK_CTX], GFP_KERNEL);
955 if (!priv->ctx)
956 return -ENOMEM;
957
958 err = nft_secmark_compute_secid(priv);
959 if (err) {
960 kfree(objp: priv->ctx);
961 return err;
962 }
963
964 security_secmark_refcount_inc();
965
966 return 0;
967}
968
969static int nft_secmark_obj_dump(struct sk_buff *skb, struct nft_object *obj,
970 bool reset)
971{
972 struct nft_secmark *priv = nft_obj_data(obj);
973 int err;
974
975 if (nla_put_string(skb, attrtype: NFTA_SECMARK_CTX, str: priv->ctx))
976 return -1;
977
978 if (reset) {
979 err = nft_secmark_compute_secid(priv);
980 if (err)
981 return err;
982 }
983
984 return 0;
985}
986
987static void nft_secmark_obj_destroy(const struct nft_ctx *ctx, struct nft_object *obj)
988{
989 struct nft_secmark *priv = nft_obj_data(obj);
990
991 security_secmark_refcount_dec();
992
993 kfree(objp: priv->ctx);
994}
995
996static const struct nft_object_ops nft_secmark_obj_ops = {
997 .type = &nft_secmark_obj_type,
998 .size = sizeof(struct nft_secmark),
999 .init = nft_secmark_obj_init,
1000 .eval = nft_secmark_obj_eval,
1001 .dump = nft_secmark_obj_dump,
1002 .destroy = nft_secmark_obj_destroy,
1003};
1004struct nft_object_type nft_secmark_obj_type __read_mostly = {
1005 .type = NFT_OBJECT_SECMARK,
1006 .ops = &nft_secmark_obj_ops,
1007 .maxattr = NFTA_SECMARK_MAX,
1008 .policy = nft_secmark_policy,
1009 .owner = THIS_MODULE,
1010};
1011#endif /* CONFIG_NETWORK_SECMARK */
1012

source code of linux/net/netfilter/nft_meta.c