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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/smp.h>
18#include <linux/static_key.h>
19#include <net/dst.h>
20#include <net/ip.h>
21#include <net/sock.h>
22#include <net/tcp_states.h> /* for TCP_TIME_WAIT */
23#include <net/netfilter/nf_tables.h>
24#include <net/netfilter/nf_tables_core.h>
25#include <net/netfilter/nft_meta.h>
26#include <net/netfilter/nf_tables_offload.h>
27
28#include <uapi/linux/netfilter_bridge.h> /* NF_BR_PRE_ROUTING */
29
30#define NFT_META_SECS_PER_MINUTE 60
31#define NFT_META_SECS_PER_HOUR 3600
32#define NFT_META_SECS_PER_DAY 86400
33#define NFT_META_DAYS_PER_WEEK 7
34
35static DEFINE_PER_CPU(struct rnd_state, nft_prandom_state);
36
37static u8 nft_meta_weekday(void)
38{
39 time64_t secs = ktime_get_real_seconds();
40 unsigned int dse;
41 u8 wday;
42
43 secs -= NFT_META_SECS_PER_MINUTE * sys_tz.tz_minuteswest;
44 dse = div_u64(secs, NFT_META_SECS_PER_DAY);
45 wday = (4 + dse) % NFT_META_DAYS_PER_WEEK;
46
47 return wday;
48}
49
50static u32 nft_meta_hour(time64_t secs)
51{
52 struct tm tm;
53
54 time64_to_tm(secs, 0, &tm);
55
56 return tm.tm_hour * NFT_META_SECS_PER_HOUR
57 + tm.tm_min * NFT_META_SECS_PER_MINUTE
58 + tm.tm_sec;
59}
60
61static noinline_for_stack void
62nft_meta_get_eval_time(enum nft_meta_keys key,
63 u32 *dest)
64{
65 switch (key) {
66 case NFT_META_TIME_NS:
67 nft_reg_store64(dest, ktime_get_real_ns());
68 break;
69 case NFT_META_TIME_DAY:
70 nft_reg_store8(dest, nft_meta_weekday());
71 break;
72 case NFT_META_TIME_HOUR:
73 *dest = nft_meta_hour(ktime_get_real_seconds());
74 break;
75 default:
76 break;
77 }
78}
79
80static noinline bool
81nft_meta_get_eval_pkttype_lo(const struct nft_pktinfo *pkt,
82 u32 *dest)
83{
84 const struct sk_buff *skb = pkt->skb;
85
86 switch (nft_pf(pkt)) {
87 case NFPROTO_IPV4:
88 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
89 nft_reg_store8(dest, PACKET_MULTICAST);
90 else
91 nft_reg_store8(dest, PACKET_BROADCAST);
92 break;
93 case NFPROTO_IPV6:
94 nft_reg_store8(dest, PACKET_MULTICAST);
95 break;
96 case NFPROTO_NETDEV:
97 switch (skb->protocol) {
98 case htons(ETH_P_IP): {
99 int noff = skb_network_offset(skb);
100 struct iphdr *iph, _iph;
101
102 iph = skb_header_pointer(skb, noff,
103 sizeof(_iph), &_iph);
104 if (!iph)
105 return false;
106
107 if (ipv4_is_multicast(iph->daddr))
108 nft_reg_store8(dest, PACKET_MULTICAST);
109 else
110 nft_reg_store8(dest, PACKET_BROADCAST);
111
112 break;
113 }
114 case htons(ETH_P_IPV6):
115 nft_reg_store8(dest, PACKET_MULTICAST);
116 break;
117 default:
118 WARN_ON_ONCE(1);
119 return false;
120 }
121 break;
122 default:
123 WARN_ON_ONCE(1);
124 return false;
125 }
126
127 return true;
128}
129
130static noinline bool
131nft_meta_get_eval_skugid(enum nft_meta_keys key,
132 u32 *dest,
133 const struct nft_pktinfo *pkt)
134{
135 struct sock *sk = skb_to_full_sk(pkt->skb);
136 struct socket *sock;
137
138 if (!sk || !sk_fullsock(sk) || !net_eq(nft_net(pkt), sock_net(sk)))
139 return false;
140
141 read_lock_bh(&sk->sk_callback_lock);
142 sock = sk->sk_socket;
143 if (!sock || !sock->file) {
144 read_unlock_bh(&sk->sk_callback_lock);
145 return false;
146 }
147
148 switch (key) {
149 case NFT_META_SKUID:
150 *dest = from_kuid_munged(sock_net(sk)->user_ns,
151 sock->file->f_cred->fsuid);
152 break;
153 case NFT_META_SKGID:
154 *dest = from_kgid_munged(sock_net(sk)->user_ns,
155 sock->file->f_cred->fsgid);
156 break;
157 default:
158 break;
159 }
160
161 read_unlock_bh(&sk->sk_callback_lock);
162 return true;
163}
164
165#ifdef CONFIG_CGROUP_NET_CLASSID
166static noinline bool
167nft_meta_get_eval_cgroup(u32 *dest, const struct nft_pktinfo *pkt)
168{
169 struct sock *sk = skb_to_full_sk(pkt->skb);
170
171 if (!sk || !sk_fullsock(sk) || !net_eq(nft_net(pkt), sock_net(sk)))
172 return false;
173
174 *dest = sock_cgroup_classid(&sk->sk_cgrp_data);
175 return true;
176}
177#endif
178
179static noinline bool nft_meta_get_eval_kind(enum nft_meta_keys key,
180 u32 *dest,
181 const struct nft_pktinfo *pkt)
182{
183 const struct net_device *in = nft_in(pkt), *out = nft_out(pkt);
184
185 switch (key) {
186 case NFT_META_IIFKIND:
187 if (!in || !in->rtnl_link_ops)
188 return false;
189 strncpy((char *)dest, in->rtnl_link_ops->kind, IFNAMSIZ);
190 break;
191 case NFT_META_OIFKIND:
192 if (!out || !out->rtnl_link_ops)
193 return false;
194 strncpy((char *)dest, out->rtnl_link_ops->kind, IFNAMSIZ);
195 break;
196 default:
197 return false;
198 }
199
200 return true;
201}
202
203static void nft_meta_store_ifindex(u32 *dest, const struct net_device *dev)
204{
205 *dest = dev ? dev->ifindex : 0;
206}
207
208static void nft_meta_store_ifname(u32 *dest, const struct net_device *dev)
209{
210 strncpy((char *)dest, dev ? dev->name : "", IFNAMSIZ);
211}
212
213static bool nft_meta_store_iftype(u32 *dest, const struct net_device *dev)
214{
215 if (!dev)
216 return false;
217
218 nft_reg_store16(dest, dev->type);
219 return true;
220}
221
222static bool nft_meta_store_ifgroup(u32 *dest, const struct net_device *dev)
223{
224 if (!dev)
225 return false;
226
227 *dest = dev->group;
228 return true;
229}
230
231static bool nft_meta_get_eval_ifname(enum nft_meta_keys key, u32 *dest,
232 const struct nft_pktinfo *pkt)
233{
234 switch (key) {
235 case NFT_META_IIFNAME:
236 nft_meta_store_ifname(dest, nft_in(pkt));
237 break;
238 case NFT_META_OIFNAME:
239 nft_meta_store_ifname(dest, nft_out(pkt));
240 break;
241 case NFT_META_IIF:
242 nft_meta_store_ifindex(dest, nft_in(pkt));
243 break;
244 case NFT_META_OIF:
245 nft_meta_store_ifindex(dest, nft_out(pkt));
246 break;
247 case NFT_META_IIFTYPE:
248 if (!nft_meta_store_iftype(dest, nft_in(pkt)))
249 return false;
250 break;
251 case NFT_META_OIFTYPE:
252 if (!nft_meta_store_iftype(dest, nft_out(pkt)))
253 return false;
254 break;
255 case NFT_META_IIFGROUP:
256 if (!nft_meta_store_ifgroup(dest, nft_in(pkt)))
257 return false;
258 break;
259 case NFT_META_OIFGROUP:
260 if (!nft_meta_store_ifgroup(dest, nft_out(pkt)))
261 return false;
262 break;
263 default:
264 return false;
265 }
266
267 return true;
268}
269
270static noinline u32 nft_prandom_u32(void)
271{
272 struct rnd_state *state = this_cpu_ptr(&nft_prandom_state);
273
274 return prandom_u32_state(state);
275}
276
277#ifdef CONFIG_IP_ROUTE_CLASSID
278static noinline bool
279nft_meta_get_eval_rtclassid(const struct sk_buff *skb, u32 *dest)
280{
281 const struct dst_entry *dst = skb_dst(skb);
282
283 if (!dst)
284 return false;
285
286 *dest = dst->tclassid;
287 return true;
288}
289#endif
290
291static noinline u32 nft_meta_get_eval_sdif(const struct nft_pktinfo *pkt)
292{
293 switch (nft_pf(pkt)) {
294 case NFPROTO_IPV4:
295 return inet_sdif(pkt->skb);
296 case NFPROTO_IPV6:
297 return inet6_sdif(pkt->skb);
298 }
299
300 return 0;
301}
302
303static noinline void
304nft_meta_get_eval_sdifname(u32 *dest, const struct nft_pktinfo *pkt)
305{
306 u32 sdif = nft_meta_get_eval_sdif(pkt);
307 const struct net_device *dev;
308
309 dev = sdif ? dev_get_by_index_rcu(nft_net(pkt), sdif) : NULL;
310 nft_meta_store_ifname(dest, dev);
311}
312
313void nft_meta_get_eval(const struct nft_expr *expr,
314 struct nft_regs *regs,
315 const struct nft_pktinfo *pkt)
316{
317 const struct nft_meta *priv = nft_expr_priv(expr);
318 const struct sk_buff *skb = pkt->skb;
319 u32 *dest = ®s->data[priv->dreg];
320
321 switch (priv->key) {
322 case NFT_META_LEN:
323 *dest = skb->len;
324 break;
325 case NFT_META_PROTOCOL:
326 nft_reg_store16(dest, (__force u16)skb->protocol);
327 break;
328 case NFT_META_NFPROTO:
329 nft_reg_store8(dest, nft_pf(pkt));
330 break;
331 case NFT_META_L4PROTO:
332 if (!pkt->tprot_set)
333 goto err;
334 nft_reg_store8(dest, pkt->tprot);
335 break;
336 case NFT_META_PRIORITY:
337 *dest = skb->priority;
338 break;
339 case NFT_META_MARK:
340 *dest = skb->mark;
341 break;
342 case NFT_META_IIF:
343 case NFT_META_OIF:
344 case NFT_META_IIFNAME:
345 case NFT_META_OIFNAME:
346 case NFT_META_IIFTYPE:
347 case NFT_META_OIFTYPE:
348 case NFT_META_IIFGROUP:
349 case NFT_META_OIFGROUP:
350 if (!nft_meta_get_eval_ifname(priv->key, dest, pkt))
351 goto err;
352 break;
353 case NFT_META_SKUID:
354 case NFT_META_SKGID:
355 if (!nft_meta_get_eval_skugid(priv->key, dest, pkt))
356 goto err;
357 break;
358#ifdef CONFIG_IP_ROUTE_CLASSID
359 case NFT_META_RTCLASSID:
360 if (!nft_meta_get_eval_rtclassid(skb, dest))
361 goto err;
362 break;
363#endif
364#ifdef CONFIG_NETWORK_SECMARK
365 case NFT_META_SECMARK:
366 *dest = skb->secmark;
367 break;
368#endif
369 case NFT_META_PKTTYPE:
370 if (skb->pkt_type != PACKET_LOOPBACK) {
371 nft_reg_store8(dest, skb->pkt_type);
372 break;
373 }
374
375 if (!nft_meta_get_eval_pkttype_lo(pkt, dest))
376 goto err;
377 break;
378 case NFT_META_CPU:
379 *dest = raw_smp_processor_id();
380 break;
381#ifdef CONFIG_CGROUP_NET_CLASSID
382 case NFT_META_CGROUP:
383 if (!nft_meta_get_eval_cgroup(dest, pkt))
384 goto err;
385 break;
386#endif
387 case NFT_META_PRANDOM:
388 *dest = nft_prandom_u32();
389 break;
390#ifdef CONFIG_XFRM
391 case NFT_META_SECPATH:
392 nft_reg_store8(dest, secpath_exists(skb));
393 break;
394#endif
395 case NFT_META_IIFKIND:
396 case NFT_META_OIFKIND:
397 if (!nft_meta_get_eval_kind(priv->key, dest, pkt))
398 goto err;
399 break;
400 case NFT_META_TIME_NS:
401 case NFT_META_TIME_DAY:
402 case NFT_META_TIME_HOUR:
403 nft_meta_get_eval_time(priv->key, dest);
404 break;
405 case NFT_META_SDIF:
406 *dest = nft_meta_get_eval_sdif(pkt);
407 break;
408 case NFT_META_SDIFNAME:
409 nft_meta_get_eval_sdifname(dest, pkt);
410 break;
411 default:
412 WARN_ON(1);
413 goto err;
414 }
415 return;
416
417err:
418 regs->verdict.code = NFT_BREAK;
419}
420EXPORT_SYMBOL_GPL(nft_meta_get_eval);
421
422void nft_meta_set_eval(const struct nft_expr *expr,
423 struct nft_regs *regs,
424 const struct nft_pktinfo *pkt)
425{
426 const struct nft_meta *meta = nft_expr_priv(expr);
427 struct sk_buff *skb = pkt->skb;
428 u32 *sreg = ®s->data[meta->sreg];
429 u32 value = *sreg;
430 u8 value8;
431
432 switch (meta->key) {
433 case NFT_META_MARK:
434 skb->mark = value;
435 break;
436 case NFT_META_PRIORITY:
437 skb->priority = value;
438 break;
439 case NFT_META_PKTTYPE:
440 value8 = nft_reg_load8(sreg);
441
442 if (skb->pkt_type != value8 &&
443 skb_pkt_type_ok(value8) &&
444 skb_pkt_type_ok(skb->pkt_type))
445 skb->pkt_type = value8;
446 break;
447 case NFT_META_NFTRACE:
448 value8 = nft_reg_load8(sreg);
449
450 skb->nf_trace = !!value8;
451 break;
452#ifdef CONFIG_NETWORK_SECMARK
453 case NFT_META_SECMARK:
454 skb->secmark = value;
455 break;
456#endif
457 default:
458 WARN_ON(1);
459 }
460}
461EXPORT_SYMBOL_GPL(nft_meta_set_eval);
462
463const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = {
464 [NFTA_META_DREG] = { .type = NLA_U32 },
465 [NFTA_META_KEY] = { .type = NLA_U32 },
466 [NFTA_META_SREG] = { .type = NLA_U32 },
467};
468EXPORT_SYMBOL_GPL(nft_meta_policy);
469
470int nft_meta_get_init(const struct nft_ctx *ctx,
471 const struct nft_expr *expr,
472 const struct nlattr * const tb[])
473{
474 struct nft_meta *priv = nft_expr_priv(expr);
475 unsigned int len;
476
477 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
478 switch (priv->key) {
479 case NFT_META_PROTOCOL:
480 case NFT_META_IIFTYPE:
481 case NFT_META_OIFTYPE:
482 len = sizeof(u16);
483 break;
484 case NFT_META_NFPROTO:
485 case NFT_META_L4PROTO:
486 case NFT_META_LEN:
487 case NFT_META_PRIORITY:
488 case NFT_META_MARK:
489 case NFT_META_IIF:
490 case NFT_META_OIF:
491 case NFT_META_SDIF:
492 case NFT_META_SKUID:
493 case NFT_META_SKGID:
494#ifdef CONFIG_IP_ROUTE_CLASSID
495 case NFT_META_RTCLASSID:
496#endif
497#ifdef CONFIG_NETWORK_SECMARK
498 case NFT_META_SECMARK:
499#endif
500 case NFT_META_PKTTYPE:
501 case NFT_META_CPU:
502 case NFT_META_IIFGROUP:
503 case NFT_META_OIFGROUP:
504#ifdef CONFIG_CGROUP_NET_CLASSID
505 case NFT_META_CGROUP:
506#endif
507 len = sizeof(u32);
508 break;
509 case NFT_META_IIFNAME:
510 case NFT_META_OIFNAME:
511 case NFT_META_IIFKIND:
512 case NFT_META_OIFKIND:
513 case NFT_META_SDIFNAME:
514 len = IFNAMSIZ;
515 break;
516 case NFT_META_PRANDOM:
517 prandom_init_once(&nft_prandom_state);
518 len = sizeof(u32);
519 break;
520#ifdef CONFIG_XFRM
521 case NFT_META_SECPATH:
522 len = sizeof(u8);
523 break;
524#endif
525 case NFT_META_TIME_NS:
526 len = sizeof(u64);
527 break;
528 case NFT_META_TIME_DAY:
529 len = sizeof(u8);
530 break;
531 case NFT_META_TIME_HOUR:
532 len = sizeof(u32);
533 break;
534 default:
535 return -EOPNOTSUPP;
536 }
537
538 return nft_parse_register_store(ctx, tb[NFTA_META_DREG], &priv->dreg,
539 NULL, NFT_DATA_VALUE, len);
540}
541EXPORT_SYMBOL_GPL(nft_meta_get_init);
542
543static int nft_meta_get_validate_sdif(const struct nft_ctx *ctx)
544{
545 unsigned int hooks;
546
547 switch (ctx->family) {
548 case NFPROTO_IPV4:
549 case NFPROTO_IPV6:
550 case NFPROTO_INET:
551 hooks = (1 << NF_INET_LOCAL_IN) |
552 (1 << NF_INET_FORWARD);
553 break;
554 default:
555 return -EOPNOTSUPP;
556 }
557
558 return nft_chain_validate_hooks(ctx->chain, hooks);
559}
560
561static int nft_meta_get_validate_xfrm(const struct nft_ctx *ctx)
562{
563#ifdef CONFIG_XFRM
564 unsigned int hooks;
565
566 switch (ctx->family) {
567 case NFPROTO_NETDEV:
568 hooks = 1 << NF_NETDEV_INGRESS;
569 break;
570 case NFPROTO_IPV4:
571 case NFPROTO_IPV6:
572 case NFPROTO_INET:
573 hooks = (1 << NF_INET_PRE_ROUTING) |
574 (1 << NF_INET_LOCAL_IN) |
575 (1 << NF_INET_FORWARD);
576 break;
577 default:
578 return -EOPNOTSUPP;
579 }
580
581 return nft_chain_validate_hooks(ctx->chain, hooks);
582#else
583 return 0;
584#endif
585}
586
587static int nft_meta_get_validate(const struct nft_ctx *ctx,
588 const struct nft_expr *expr,
589 const struct nft_data **data)
590{
591 const struct nft_meta *priv = nft_expr_priv(expr);
592
593 switch (priv->key) {
594 case NFT_META_SECPATH:
595 return nft_meta_get_validate_xfrm(ctx);
596 case NFT_META_SDIF:
597 case NFT_META_SDIFNAME:
598 return nft_meta_get_validate_sdif(ctx);
599 default:
600 break;
601 }
602
603 return 0;
604}
605
606int nft_meta_set_validate(const struct nft_ctx *ctx,
607 const struct nft_expr *expr,
608 const struct nft_data **data)
609{
610 struct nft_meta *priv = nft_expr_priv(expr);
611 unsigned int hooks;
612
613 if (priv->key != NFT_META_PKTTYPE)
614 return 0;
615
616 switch (ctx->family) {
617 case NFPROTO_BRIDGE:
618 hooks = 1 << NF_BR_PRE_ROUTING;
619 break;
620 case NFPROTO_NETDEV:
621 hooks = 1 << NF_NETDEV_INGRESS;
622 break;
623 case NFPROTO_IPV4:
624 case NFPROTO_IPV6:
625 case NFPROTO_INET:
626 hooks = 1 << NF_INET_PRE_ROUTING;
627 break;
628 default:
629 return -EOPNOTSUPP;
630 }
631
632 return nft_chain_validate_hooks(ctx->chain, hooks);
633}
634EXPORT_SYMBOL_GPL(nft_meta_set_validate);
635
636int nft_meta_set_init(const struct nft_ctx *ctx,
637 const struct nft_expr *expr,
638 const struct nlattr * const tb[])
639{
640 struct nft_meta *priv = nft_expr_priv(expr);
641 unsigned int len;
642 int err;
643
644 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
645 switch (priv->key) {
646 case NFT_META_MARK:
647 case NFT_META_PRIORITY:
648#ifdef CONFIG_NETWORK_SECMARK
649 case NFT_META_SECMARK:
650#endif
651 len = sizeof(u32);
652 break;
653 case NFT_META_NFTRACE:
654 len = sizeof(u8);
655 break;
656 case NFT_META_PKTTYPE:
657 len = sizeof(u8);
658 break;
659 default:
660 return -EOPNOTSUPP;
661 }
662
663 err = nft_parse_register_load(tb[NFTA_META_SREG], &priv->sreg, len);
664 if (err < 0)
665 return err;
666
667 if (priv->key == NFT_META_NFTRACE)
668 static_branch_inc(&nft_trace_enabled);
669
670 return 0;
671}
672EXPORT_SYMBOL_GPL(nft_meta_set_init);
673
674int nft_meta_get_dump(struct sk_buff *skb,
675 const struct nft_expr *expr)
676{
677 const struct nft_meta *priv = nft_expr_priv(expr);
678
679 if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
680 goto nla_put_failure;
681 if (nft_dump_register(skb, NFTA_META_DREG, priv->dreg))
682 goto nla_put_failure;
683 return 0;
684
685nla_put_failure:
686 return -1;
687}
688EXPORT_SYMBOL_GPL(nft_meta_get_dump);
689
690int nft_meta_set_dump(struct sk_buff *skb, const struct nft_expr *expr)
691{
692 const struct nft_meta *priv = nft_expr_priv(expr);
693
694 if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
695 goto nla_put_failure;
696 if (nft_dump_register(skb, NFTA_META_SREG, priv->sreg))
697 goto nla_put_failure;
698
699 return 0;
700
701nla_put_failure:
702 return -1;
703}
704EXPORT_SYMBOL_GPL(nft_meta_set_dump);
705
706void nft_meta_set_destroy(const struct nft_ctx *ctx,
707 const struct nft_expr *expr)
708{
709 const struct nft_meta *priv = nft_expr_priv(expr);
710
711 if (priv->key == NFT_META_NFTRACE)
712 static_branch_dec(&nft_trace_enabled);
713}
714EXPORT_SYMBOL_GPL(nft_meta_set_destroy);
715
716static int nft_meta_get_offload(struct nft_offload_ctx *ctx,
717 struct nft_flow_rule *flow,
718 const struct nft_expr *expr)
719{
720 const struct nft_meta *priv = nft_expr_priv(expr);
721 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
722
723 switch (priv->key) {
724 case NFT_META_PROTOCOL:
725 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, n_proto,
726 sizeof(__u16), reg);
727 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
728 break;
729 case NFT_META_L4PROTO:
730 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
731 sizeof(__u8), reg);
732 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
733 break;
734 case NFT_META_IIF:
735 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
736 ingress_ifindex, sizeof(__u32), reg);
737 break;
738 case NFT_META_IIFTYPE:
739 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
740 ingress_iftype, sizeof(__u16), reg);
741 break;
742 default:
743 return -EOPNOTSUPP;
744 }
745
746 return 0;
747}
748
749static const struct nft_expr_ops nft_meta_get_ops = {
750 .type = &nft_meta_type,
751 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
752 .eval = nft_meta_get_eval,
753 .init = nft_meta_get_init,
754 .dump = nft_meta_get_dump,
755 .validate = nft_meta_get_validate,
756 .offload = nft_meta_get_offload,
757};
758
759static const struct nft_expr_ops nft_meta_set_ops = {
760 .type = &nft_meta_type,
761 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
762 .eval = nft_meta_set_eval,
763 .init = nft_meta_set_init,
764 .destroy = nft_meta_set_destroy,
765 .dump = nft_meta_set_dump,
766 .validate = nft_meta_set_validate,
767};
768
769static const struct nft_expr_ops *
770nft_meta_select_ops(const struct nft_ctx *ctx,
771 const struct nlattr * const tb[])
772{
773 if (tb[NFTA_META_KEY] == NULL)
774 return ERR_PTR(-EINVAL);
775
776 if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
777 return ERR_PTR(-EINVAL);
778
779#if IS_ENABLED(CONFIG_NF_TABLES_BRIDGE) && IS_MODULE(CONFIG_NFT_BRIDGE_META)
780 if (ctx->family == NFPROTO_BRIDGE)
781 return ERR_PTR(-EAGAIN);
782#endif
783 if (tb[NFTA_META_DREG])
784 return &nft_meta_get_ops;
785
786 if (tb[NFTA_META_SREG])
787 return &nft_meta_set_ops;
788
789 return ERR_PTR(-EINVAL);
790}
791
792struct nft_expr_type nft_meta_type __read_mostly = {
793 .name = "meta",
794 .select_ops = nft_meta_select_ops,
795 .policy = nft_meta_policy,
796 .maxattr = NFTA_META_MAX,
797 .owner = THIS_MODULE,
798};
799
800#ifdef CONFIG_NETWORK_SECMARK
801struct nft_secmark {
802 u32 secid;
803 char *ctx;
804};
805
806static const struct nla_policy nft_secmark_policy[NFTA_SECMARK_MAX + 1] = {
807 [NFTA_SECMARK_CTX] = { .type = NLA_STRING, .len = NFT_SECMARK_CTX_MAXLEN },
808};
809
810static int nft_secmark_compute_secid(struct nft_secmark *priv)
811{
812 u32 tmp_secid = 0;
813 int err;
814
815 err = security_secctx_to_secid(priv->ctx, strlen(priv->ctx), &tmp_secid);
816 if (err)
817 return err;
818
819 if (!tmp_secid)
820 return -ENOENT;
821
822 err = security_secmark_relabel_packet(tmp_secid);
823 if (err)
824 return err;
825
826 priv->secid = tmp_secid;
827 return 0;
828}
829
830static void nft_secmark_obj_eval(struct nft_object *obj, struct nft_regs *regs,
831 const struct nft_pktinfo *pkt)
832{
833 const struct nft_secmark *priv = nft_obj_data(obj);
834 struct sk_buff *skb = pkt->skb;
835
836 skb->secmark = priv->secid;
837}
838
839static int nft_secmark_obj_init(const struct nft_ctx *ctx,
840 const struct nlattr * const tb[],
841 struct nft_object *obj)
842{
843 struct nft_secmark *priv = nft_obj_data(obj);
844 int err;
845
846 if (tb[NFTA_SECMARK_CTX] == NULL)
847 return -EINVAL;
848
849 priv->ctx = nla_strdup(tb[NFTA_SECMARK_CTX], GFP_KERNEL);
850 if (!priv->ctx)
851 return -ENOMEM;
852
853 err = nft_secmark_compute_secid(priv);
854 if (err) {
855 kfree(priv->ctx);
856 return err;
857 }
858
859 security_secmark_refcount_inc();
860
861 return 0;
862}
863
864static int nft_secmark_obj_dump(struct sk_buff *skb, struct nft_object *obj,
865 bool reset)
866{
867 struct nft_secmark *priv = nft_obj_data(obj);
868 int err;
869
870 if (nla_put_string(skb, NFTA_SECMARK_CTX, priv->ctx))
871 return -1;
872
873 if (reset) {
874 err = nft_secmark_compute_secid(priv);
875 if (err)
876 return err;
877 }
878
879 return 0;
880}
881
882static void nft_secmark_obj_destroy(const struct nft_ctx *ctx, struct nft_object *obj)
883{
884 struct nft_secmark *priv = nft_obj_data(obj);
885
886 security_secmark_refcount_dec();
887
888 kfree(priv->ctx);
889}
890
891static const struct nft_object_ops nft_secmark_obj_ops = {
892 .type = &nft_secmark_obj_type,
893 .size = sizeof(struct nft_secmark),
894 .init = nft_secmark_obj_init,
895 .eval = nft_secmark_obj_eval,
896 .dump = nft_secmark_obj_dump,
897 .destroy = nft_secmark_obj_destroy,
898};
899struct nft_object_type nft_secmark_obj_type __read_mostly = {
900 .type = NFT_OBJECT_SECMARK,
901 .ops = &nft_secmark_obj_ops,
902 .maxattr = NFTA_SECMARK_MAX,
903 .policy = nft_secmark_policy,
904 .owner = THIS_MODULE,
905};
906#endif /* CONFIG_NETWORK_SECMARK */
1/*
2 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * Development of this code funded by Astaro AG (http://www.astaro.com/)
9 */
10
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/module.h>
14#include <linux/netlink.h>
15#include <linux/netfilter.h>
16#include <linux/netfilter/nf_tables.h>
17#include <linux/in.h>
18#include <linux/ip.h>
19#include <linux/ipv6.h>
20#include <linux/smp.h>
21#include <linux/static_key.h>
22#include <net/dst.h>
23#include <net/sock.h>
24#include <net/tcp_states.h> /* for TCP_TIME_WAIT */
25#include <net/netfilter/nf_tables.h>
26#include <net/netfilter/nf_tables_core.h>
27#include <net/netfilter/nft_meta.h>
28
29#include <uapi/linux/netfilter_bridge.h> /* NF_BR_PRE_ROUTING */
30
31static DEFINE_PER_CPU(struct rnd_state, nft_prandom_state);
32
33void nft_meta_get_eval(const struct nft_expr *expr,
34 struct nft_regs *regs,
35 const struct nft_pktinfo *pkt)
36{
37 const struct nft_meta *priv = nft_expr_priv(expr);
38 const struct sk_buff *skb = pkt->skb;
39 const struct net_device *in = pkt->in, *out = pkt->out;
40 struct sock *sk;
41 u32 *dest = ®s->data[priv->dreg];
42
43 switch (priv->key) {
44 case NFT_META_LEN:
45 *dest = skb->len;
46 break;
47 case NFT_META_PROTOCOL:
48 *dest = 0;
49 *(__be16 *)dest = skb->protocol;
50 break;
51 case NFT_META_NFPROTO:
52 *dest = pkt->pf;
53 break;
54 case NFT_META_L4PROTO:
55 *dest = pkt->tprot;
56 break;
57 case NFT_META_PRIORITY:
58 *dest = skb->priority;
59 break;
60 case NFT_META_MARK:
61 *dest = skb->mark;
62 break;
63 case NFT_META_IIF:
64 if (in == NULL)
65 goto err;
66 *dest = in->ifindex;
67 break;
68 case NFT_META_OIF:
69 if (out == NULL)
70 goto err;
71 *dest = out->ifindex;
72 break;
73 case NFT_META_IIFNAME:
74 if (in == NULL)
75 goto err;
76 strncpy((char *)dest, in->name, IFNAMSIZ);
77 break;
78 case NFT_META_OIFNAME:
79 if (out == NULL)
80 goto err;
81 strncpy((char *)dest, out->name, IFNAMSIZ);
82 break;
83 case NFT_META_IIFTYPE:
84 if (in == NULL)
85 goto err;
86 *dest = 0;
87 *(u16 *)dest = in->type;
88 break;
89 case NFT_META_OIFTYPE:
90 if (out == NULL)
91 goto err;
92 *dest = 0;
93 *(u16 *)dest = out->type;
94 break;
95 case NFT_META_SKUID:
96 sk = skb_to_full_sk(skb);
97 if (!sk || !sk_fullsock(sk))
98 goto err;
99
100 read_lock_bh(&sk->sk_callback_lock);
101 if (sk->sk_socket == NULL ||
102 sk->sk_socket->file == NULL) {
103 read_unlock_bh(&sk->sk_callback_lock);
104 goto err;
105 }
106
107 *dest = from_kuid_munged(&init_user_ns,
108 sk->sk_socket->file->f_cred->fsuid);
109 read_unlock_bh(&sk->sk_callback_lock);
110 break;
111 case NFT_META_SKGID:
112 sk = skb_to_full_sk(skb);
113 if (!sk || !sk_fullsock(sk))
114 goto err;
115
116 read_lock_bh(&sk->sk_callback_lock);
117 if (sk->sk_socket == NULL ||
118 sk->sk_socket->file == NULL) {
119 read_unlock_bh(&sk->sk_callback_lock);
120 goto err;
121 }
122 *dest = from_kgid_munged(&init_user_ns,
123 sk->sk_socket->file->f_cred->fsgid);
124 read_unlock_bh(&sk->sk_callback_lock);
125 break;
126#ifdef CONFIG_IP_ROUTE_CLASSID
127 case NFT_META_RTCLASSID: {
128 const struct dst_entry *dst = skb_dst(skb);
129
130 if (dst == NULL)
131 goto err;
132 *dest = dst->tclassid;
133 break;
134 }
135#endif
136#ifdef CONFIG_NETWORK_SECMARK
137 case NFT_META_SECMARK:
138 *dest = skb->secmark;
139 break;
140#endif
141 case NFT_META_PKTTYPE:
142 if (skb->pkt_type != PACKET_LOOPBACK) {
143 *dest = skb->pkt_type;
144 break;
145 }
146
147 switch (pkt->pf) {
148 case NFPROTO_IPV4:
149 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
150 *dest = PACKET_MULTICAST;
151 else
152 *dest = PACKET_BROADCAST;
153 break;
154 case NFPROTO_IPV6:
155 if (ipv6_hdr(skb)->daddr.s6_addr[0] == 0xFF)
156 *dest = PACKET_MULTICAST;
157 else
158 *dest = PACKET_BROADCAST;
159 break;
160 default:
161 WARN_ON(1);
162 goto err;
163 }
164 break;
165 case NFT_META_CPU:
166 *dest = raw_smp_processor_id();
167 break;
168 case NFT_META_IIFGROUP:
169 if (in == NULL)
170 goto err;
171 *dest = in->group;
172 break;
173 case NFT_META_OIFGROUP:
174 if (out == NULL)
175 goto err;
176 *dest = out->group;
177 break;
178#ifdef CONFIG_CGROUP_NET_CLASSID
179 case NFT_META_CGROUP:
180 sk = skb_to_full_sk(skb);
181 if (!sk || !sk_fullsock(sk))
182 goto err;
183 *dest = sock_cgroup_classid(&sk->sk_cgrp_data);
184 break;
185#endif
186 case NFT_META_PRANDOM: {
187 struct rnd_state *state = this_cpu_ptr(&nft_prandom_state);
188 *dest = prandom_u32_state(state);
189 break;
190 }
191 default:
192 WARN_ON(1);
193 goto err;
194 }
195 return;
196
197err:
198 regs->verdict.code = NFT_BREAK;
199}
200EXPORT_SYMBOL_GPL(nft_meta_get_eval);
201
202/* don't change or set _LOOPBACK, _USER, etc. */
203static bool pkt_type_ok(u32 p)
204{
205 return p == PACKET_HOST || p == PACKET_BROADCAST ||
206 p == PACKET_MULTICAST || p == PACKET_OTHERHOST;
207}
208
209void nft_meta_set_eval(const struct nft_expr *expr,
210 struct nft_regs *regs,
211 const struct nft_pktinfo *pkt)
212{
213 const struct nft_meta *meta = nft_expr_priv(expr);
214 struct sk_buff *skb = pkt->skb;
215 u32 value = regs->data[meta->sreg];
216
217 switch (meta->key) {
218 case NFT_META_MARK:
219 skb->mark = value;
220 break;
221 case NFT_META_PRIORITY:
222 skb->priority = value;
223 break;
224 case NFT_META_PKTTYPE:
225 if (skb->pkt_type != value &&
226 pkt_type_ok(value) && pkt_type_ok(skb->pkt_type))
227 skb->pkt_type = value;
228 break;
229 case NFT_META_NFTRACE:
230 skb->nf_trace = 1;
231 break;
232 default:
233 WARN_ON(1);
234 }
235}
236EXPORT_SYMBOL_GPL(nft_meta_set_eval);
237
238const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = {
239 [NFTA_META_DREG] = { .type = NLA_U32 },
240 [NFTA_META_KEY] = { .type = NLA_U32 },
241 [NFTA_META_SREG] = { .type = NLA_U32 },
242};
243EXPORT_SYMBOL_GPL(nft_meta_policy);
244
245int nft_meta_get_init(const struct nft_ctx *ctx,
246 const struct nft_expr *expr,
247 const struct nlattr * const tb[])
248{
249 struct nft_meta *priv = nft_expr_priv(expr);
250 unsigned int len;
251
252 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
253 switch (priv->key) {
254 case NFT_META_PROTOCOL:
255 case NFT_META_IIFTYPE:
256 case NFT_META_OIFTYPE:
257 len = sizeof(u16);
258 break;
259 case NFT_META_NFPROTO:
260 case NFT_META_L4PROTO:
261 case NFT_META_LEN:
262 case NFT_META_PRIORITY:
263 case NFT_META_MARK:
264 case NFT_META_IIF:
265 case NFT_META_OIF:
266 case NFT_META_SKUID:
267 case NFT_META_SKGID:
268#ifdef CONFIG_IP_ROUTE_CLASSID
269 case NFT_META_RTCLASSID:
270#endif
271#ifdef CONFIG_NETWORK_SECMARK
272 case NFT_META_SECMARK:
273#endif
274 case NFT_META_PKTTYPE:
275 case NFT_META_CPU:
276 case NFT_META_IIFGROUP:
277 case NFT_META_OIFGROUP:
278#ifdef CONFIG_CGROUP_NET_CLASSID
279 case NFT_META_CGROUP:
280#endif
281 len = sizeof(u32);
282 break;
283 case NFT_META_IIFNAME:
284 case NFT_META_OIFNAME:
285 len = IFNAMSIZ;
286 break;
287 case NFT_META_PRANDOM:
288 prandom_init_once(&nft_prandom_state);
289 len = sizeof(u32);
290 break;
291 default:
292 return -EOPNOTSUPP;
293 }
294
295 priv->dreg = nft_parse_register(tb[NFTA_META_DREG]);
296 return nft_validate_register_store(ctx, priv->dreg, NULL,
297 NFT_DATA_VALUE, len);
298}
299EXPORT_SYMBOL_GPL(nft_meta_get_init);
300
301static int nft_meta_set_init_pkttype(const struct nft_ctx *ctx)
302{
303 unsigned int hooks;
304
305 switch (ctx->afi->family) {
306 case NFPROTO_BRIDGE:
307 hooks = 1 << NF_BR_PRE_ROUTING;
308 break;
309 case NFPROTO_NETDEV:
310 hooks = 1 << NF_NETDEV_INGRESS;
311 break;
312 default:
313 return -EOPNOTSUPP;
314 }
315
316 return nft_chain_validate_hooks(ctx->chain, hooks);
317}
318
319int nft_meta_set_init(const struct nft_ctx *ctx,
320 const struct nft_expr *expr,
321 const struct nlattr * const tb[])
322{
323 struct nft_meta *priv = nft_expr_priv(expr);
324 unsigned int len;
325 int err;
326
327 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
328 switch (priv->key) {
329 case NFT_META_MARK:
330 case NFT_META_PRIORITY:
331 len = sizeof(u32);
332 break;
333 case NFT_META_NFTRACE:
334 len = sizeof(u8);
335 break;
336 case NFT_META_PKTTYPE:
337 err = nft_meta_set_init_pkttype(ctx);
338 if (err)
339 return err;
340 len = sizeof(u8);
341 break;
342 default:
343 return -EOPNOTSUPP;
344 }
345
346 priv->sreg = nft_parse_register(tb[NFTA_META_SREG]);
347 err = nft_validate_register_load(priv->sreg, len);
348 if (err < 0)
349 return err;
350
351 if (priv->key == NFT_META_NFTRACE)
352 static_branch_inc(&nft_trace_enabled);
353
354 return 0;
355}
356EXPORT_SYMBOL_GPL(nft_meta_set_init);
357
358int nft_meta_get_dump(struct sk_buff *skb,
359 const struct nft_expr *expr)
360{
361 const struct nft_meta *priv = nft_expr_priv(expr);
362
363 if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
364 goto nla_put_failure;
365 if (nft_dump_register(skb, NFTA_META_DREG, priv->dreg))
366 goto nla_put_failure;
367 return 0;
368
369nla_put_failure:
370 return -1;
371}
372EXPORT_SYMBOL_GPL(nft_meta_get_dump);
373
374int nft_meta_set_dump(struct sk_buff *skb,
375 const struct nft_expr *expr)
376{
377 const struct nft_meta *priv = nft_expr_priv(expr);
378
379 if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
380 goto nla_put_failure;
381 if (nft_dump_register(skb, NFTA_META_SREG, priv->sreg))
382 goto nla_put_failure;
383
384 return 0;
385
386nla_put_failure:
387 return -1;
388}
389EXPORT_SYMBOL_GPL(nft_meta_set_dump);
390
391void nft_meta_set_destroy(const struct nft_ctx *ctx,
392 const struct nft_expr *expr)
393{
394 const struct nft_meta *priv = nft_expr_priv(expr);
395
396 if (priv->key == NFT_META_NFTRACE)
397 static_branch_dec(&nft_trace_enabled);
398}
399EXPORT_SYMBOL_GPL(nft_meta_set_destroy);
400
401static struct nft_expr_type nft_meta_type;
402static const struct nft_expr_ops nft_meta_get_ops = {
403 .type = &nft_meta_type,
404 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
405 .eval = nft_meta_get_eval,
406 .init = nft_meta_get_init,
407 .dump = nft_meta_get_dump,
408};
409
410static const struct nft_expr_ops nft_meta_set_ops = {
411 .type = &nft_meta_type,
412 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
413 .eval = nft_meta_set_eval,
414 .init = nft_meta_set_init,
415 .destroy = nft_meta_set_destroy,
416 .dump = nft_meta_set_dump,
417};
418
419static const struct nft_expr_ops *
420nft_meta_select_ops(const struct nft_ctx *ctx,
421 const struct nlattr * const tb[])
422{
423 if (tb[NFTA_META_KEY] == NULL)
424 return ERR_PTR(-EINVAL);
425
426 if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
427 return ERR_PTR(-EINVAL);
428
429 if (tb[NFTA_META_DREG])
430 return &nft_meta_get_ops;
431
432 if (tb[NFTA_META_SREG])
433 return &nft_meta_set_ops;
434
435 return ERR_PTR(-EINVAL);
436}
437
438static struct nft_expr_type nft_meta_type __read_mostly = {
439 .name = "meta",
440 .select_ops = &nft_meta_select_ops,
441 .policy = nft_meta_policy,
442 .maxattr = NFTA_META_MAX,
443 .owner = THIS_MODULE,
444};
445
446static int __init nft_meta_module_init(void)
447{
448 return nft_register_expr(&nft_meta_type);
449}
450
451static void __exit nft_meta_module_exit(void)
452{
453 nft_unregister_expr(&nft_meta_type);
454}
455
456module_init(nft_meta_module_init);
457module_exit(nft_meta_module_exit);
458
459MODULE_LICENSE("GPL");
460MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
461MODULE_ALIAS_NFT_EXPR("meta");