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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/sock.h>
21#include <net/tcp_states.h>
22#include <net/netfilter/nf_tables.h>
23#include <net/netfilter/nf_tables_core.h>
24#include <net/netfilter/nft_meta.h>
25#include <net/netfilter/nf_tables_offload.h>
26
27#include <uapi/linux/netfilter_bridge.h>
28
29#define NFT_META_SECS_PER_MINUTE 60
30#define NFT_META_SECS_PER_HOUR 3600
31#define NFT_META_SECS_PER_DAY 86400
32#define NFT_META_DAYS_PER_WEEK 7
33
34static DEFINE_PER_CPU(struct rnd_state, nft_prandom_state);
35
36static u8 nft_meta_weekday(unsigned long secs)
37{
38 unsigned int dse;
39 u8 wday;
40
41 secs -= NFT_META_SECS_PER_MINUTE * sys_tz.tz_minuteswest;
42 dse = secs / NFT_META_SECS_PER_DAY;
43 wday = (4 + dse) % NFT_META_DAYS_PER_WEEK;
44
45 return wday;
46}
47
48static u32 nft_meta_hour(unsigned long secs)
49{
50 struct tm tm;
51
52 time64_to_tm(secs, 0, &tm);
53
54 return tm.tm_hour * NFT_META_SECS_PER_HOUR
55 + tm.tm_min * NFT_META_SECS_PER_MINUTE
56 + tm.tm_sec;
57}
58
59void nft_meta_get_eval(const struct nft_expr *expr,
60 struct nft_regs *regs,
61 const struct nft_pktinfo *pkt)
62{
63 const struct nft_meta *priv = nft_expr_priv(expr);
64 const struct sk_buff *skb = pkt->skb;
65 const struct net_device *in = nft_in(pkt), *out = nft_out(pkt);
66 struct sock *sk;
67 u32 *dest = ®s->data[priv->dreg];
68
69 switch (priv->key) {
70 case NFT_META_LEN:
71 *dest = skb->len;
72 break;
73 case NFT_META_PROTOCOL:
74 nft_reg_store16(dest, (__force u16)skb->protocol);
75 break;
76 case NFT_META_NFPROTO:
77 nft_reg_store8(dest, nft_pf(pkt));
78 break;
79 case NFT_META_L4PROTO:
80 if (!pkt->tprot_set)
81 goto err;
82 nft_reg_store8(dest, pkt->tprot);
83 break;
84 case NFT_META_PRIORITY:
85 *dest = skb->priority;
86 break;
87 case NFT_META_MARK:
88 *dest = skb->mark;
89 break;
90 case NFT_META_IIF:
91 *dest = in ? in->ifindex : 0;
92 break;
93 case NFT_META_OIF:
94 *dest = out ? out->ifindex : 0;
95 break;
96 case NFT_META_IIFNAME:
97 strncpy((char *)dest, in ? in->name : "", IFNAMSIZ);
98 break;
99 case NFT_META_OIFNAME:
100 strncpy((char *)dest, out ? out->name : "", IFNAMSIZ);
101 break;
102 case NFT_META_IIFTYPE:
103 if (in == NULL)
104 goto err;
105 nft_reg_store16(dest, in->type);
106 break;
107 case NFT_META_OIFTYPE:
108 if (out == NULL)
109 goto err;
110 nft_reg_store16(dest, out->type);
111 break;
112 case NFT_META_SKUID:
113 sk = skb_to_full_sk(skb);
114 if (!sk || !sk_fullsock(sk) ||
115 !net_eq(nft_net(pkt), sock_net(sk)))
116 goto err;
117
118 read_lock_bh(&sk->sk_callback_lock);
119 if (sk->sk_socket == NULL ||
120 sk->sk_socket->file == NULL) {
121 read_unlock_bh(&sk->sk_callback_lock);
122 goto err;
123 }
124
125 *dest = from_kuid_munged(&init_user_ns,
126 sk->sk_socket->file->f_cred->fsuid);
127 read_unlock_bh(&sk->sk_callback_lock);
128 break;
129 case NFT_META_SKGID:
130 sk = skb_to_full_sk(skb);
131 if (!sk || !sk_fullsock(sk) ||
132 !net_eq(nft_net(pkt), sock_net(sk)))
133 goto err;
134
135 read_lock_bh(&sk->sk_callback_lock);
136 if (sk->sk_socket == NULL ||
137 sk->sk_socket->file == NULL) {
138 read_unlock_bh(&sk->sk_callback_lock);
139 goto err;
140 }
141 *dest = from_kgid_munged(&init_user_ns,
142 sk->sk_socket->file->f_cred->fsgid);
143 read_unlock_bh(&sk->sk_callback_lock);
144 break;
145#ifdef CONFIG_IP_ROUTE_CLASSID
146 case NFT_META_RTCLASSID: {
147 const struct dst_entry *dst = skb_dst(skb);
148
149 if (dst == NULL)
150 goto err;
151 *dest = dst->tclassid;
152 break;
153 }
154#endif
155#ifdef CONFIG_NETWORK_SECMARK
156 case NFT_META_SECMARK:
157 *dest = skb->secmark;
158 break;
159#endif
160 case NFT_META_PKTTYPE:
161 if (skb->pkt_type != PACKET_LOOPBACK) {
162 nft_reg_store8(dest, skb->pkt_type);
163 break;
164 }
165
166 switch (nft_pf(pkt)) {
167 case NFPROTO_IPV4:
168 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
169 nft_reg_store8(dest, PACKET_MULTICAST);
170 else
171 nft_reg_store8(dest, PACKET_BROADCAST);
172 break;
173 case NFPROTO_IPV6:
174 nft_reg_store8(dest, PACKET_MULTICAST);
175 break;
176 case NFPROTO_NETDEV:
177 switch (skb->protocol) {
178 case htons(ETH_P_IP): {
179 int noff = skb_network_offset(skb);
180 struct iphdr *iph, _iph;
181
182 iph = skb_header_pointer(skb, noff,
183 sizeof(_iph), &_iph);
184 if (!iph)
185 goto err;
186
187 if (ipv4_is_multicast(iph->daddr))
188 nft_reg_store8(dest, PACKET_MULTICAST);
189 else
190 nft_reg_store8(dest, PACKET_BROADCAST);
191
192 break;
193 }
194 case htons(ETH_P_IPV6):
195 nft_reg_store8(dest, PACKET_MULTICAST);
196 break;
197 default:
198 WARN_ON_ONCE(1);
199 goto err;
200 }
201 break;
202 default:
203 WARN_ON_ONCE(1);
204 goto err;
205 }
206 break;
207 case NFT_META_CPU:
208 *dest = raw_smp_processor_id();
209 break;
210 case NFT_META_IIFGROUP:
211 if (in == NULL)
212 goto err;
213 *dest = in->group;
214 break;
215 case NFT_META_OIFGROUP:
216 if (out == NULL)
217 goto err;
218 *dest = out->group;
219 break;
220#ifdef CONFIG_CGROUP_NET_CLASSID
221 case NFT_META_CGROUP:
222 sk = skb_to_full_sk(skb);
223 if (!sk || !sk_fullsock(sk) ||
224 !net_eq(nft_net(pkt), sock_net(sk)))
225 goto err;
226 *dest = sock_cgroup_classid(&sk->sk_cgrp_data);
227 break;
228#endif
229 case NFT_META_PRANDOM: {
230 struct rnd_state *state = this_cpu_ptr(&nft_prandom_state);
231 *dest = prandom_u32_state(state);
232 break;
233 }
234#ifdef CONFIG_XFRM
235 case NFT_META_SECPATH:
236 nft_reg_store8(dest, secpath_exists(skb));
237 break;
238#endif
239 case NFT_META_IIFKIND:
240 if (in == NULL || in->rtnl_link_ops == NULL)
241 goto err;
242 strncpy((char *)dest, in->rtnl_link_ops->kind, IFNAMSIZ);
243 break;
244 case NFT_META_OIFKIND:
245 if (out == NULL || out->rtnl_link_ops == NULL)
246 goto err;
247 strncpy((char *)dest, out->rtnl_link_ops->kind, IFNAMSIZ);
248 break;
249 case NFT_META_TIME_NS:
250 nft_reg_store64(dest, ktime_get_real_ns());
251 break;
252 case NFT_META_TIME_DAY:
253 nft_reg_store8(dest, nft_meta_weekday(get_seconds()));
254 break;
255 case NFT_META_TIME_HOUR:
256 *dest = nft_meta_hour(get_seconds());
257 break;
258 default:
259 WARN_ON(1);
260 goto err;
261 }
262 return;
263
264err:
265 regs->verdict.code = NFT_BREAK;
266}
267EXPORT_SYMBOL_GPL(nft_meta_get_eval);
268
269void nft_meta_set_eval(const struct nft_expr *expr,
270 struct nft_regs *regs,
271 const struct nft_pktinfo *pkt)
272{
273 const struct nft_meta *meta = nft_expr_priv(expr);
274 struct sk_buff *skb = pkt->skb;
275 u32 *sreg = ®s->data[meta->sreg];
276 u32 value = *sreg;
277 u8 value8;
278
279 switch (meta->key) {
280 case NFT_META_MARK:
281 skb->mark = value;
282 break;
283 case NFT_META_PRIORITY:
284 skb->priority = value;
285 break;
286 case NFT_META_PKTTYPE:
287 value8 = nft_reg_load8(sreg);
288
289 if (skb->pkt_type != value8 &&
290 skb_pkt_type_ok(value8) &&
291 skb_pkt_type_ok(skb->pkt_type))
292 skb->pkt_type = value8;
293 break;
294 case NFT_META_NFTRACE:
295 value8 = nft_reg_load8(sreg);
296
297 skb->nf_trace = !!value8;
298 break;
299#ifdef CONFIG_NETWORK_SECMARK
300 case NFT_META_SECMARK:
301 skb->secmark = value;
302 break;
303#endif
304 default:
305 WARN_ON(1);
306 }
307}
308EXPORT_SYMBOL_GPL(nft_meta_set_eval);
309
310const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = {
311 [NFTA_META_DREG] = { .type = NLA_U32 },
312 [NFTA_META_KEY] = { .type = NLA_U32 },
313 [NFTA_META_SREG] = { .type = NLA_U32 },
314};
315EXPORT_SYMBOL_GPL(nft_meta_policy);
316
317int nft_meta_get_init(const struct nft_ctx *ctx,
318 const struct nft_expr *expr,
319 const struct nlattr * const tb[])
320{
321 struct nft_meta *priv = nft_expr_priv(expr);
322 unsigned int len;
323
324 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
325 switch (priv->key) {
326 case NFT_META_PROTOCOL:
327 case NFT_META_IIFTYPE:
328 case NFT_META_OIFTYPE:
329 len = sizeof(u16);
330 break;
331 case NFT_META_NFPROTO:
332 case NFT_META_L4PROTO:
333 case NFT_META_LEN:
334 case NFT_META_PRIORITY:
335 case NFT_META_MARK:
336 case NFT_META_IIF:
337 case NFT_META_OIF:
338 case NFT_META_SKUID:
339 case NFT_META_SKGID:
340#ifdef CONFIG_IP_ROUTE_CLASSID
341 case NFT_META_RTCLASSID:
342#endif
343#ifdef CONFIG_NETWORK_SECMARK
344 case NFT_META_SECMARK:
345#endif
346 case NFT_META_PKTTYPE:
347 case NFT_META_CPU:
348 case NFT_META_IIFGROUP:
349 case NFT_META_OIFGROUP:
350#ifdef CONFIG_CGROUP_NET_CLASSID
351 case NFT_META_CGROUP:
352#endif
353 len = sizeof(u32);
354 break;
355 case NFT_META_IIFNAME:
356 case NFT_META_OIFNAME:
357 case NFT_META_IIFKIND:
358 case NFT_META_OIFKIND:
359 len = IFNAMSIZ;
360 break;
361 case NFT_META_PRANDOM:
362 prandom_init_once(&nft_prandom_state);
363 len = sizeof(u32);
364 break;
365#ifdef CONFIG_XFRM
366 case NFT_META_SECPATH:
367 len = sizeof(u8);
368 break;
369#endif
370 case NFT_META_TIME_NS:
371 len = sizeof(u64);
372 break;
373 case NFT_META_TIME_DAY:
374 len = sizeof(u8);
375 break;
376 case NFT_META_TIME_HOUR:
377 len = sizeof(u32);
378 break;
379 default:
380 return -EOPNOTSUPP;
381 }
382
383 priv->dreg = nft_parse_register(tb[NFTA_META_DREG]);
384 return nft_validate_register_store(ctx, priv->dreg, NULL,
385 NFT_DATA_VALUE, len);
386}
387EXPORT_SYMBOL_GPL(nft_meta_get_init);
388
389static int nft_meta_get_validate(const struct nft_ctx *ctx,
390 const struct nft_expr *expr,
391 const struct nft_data **data)
392{
393#ifdef CONFIG_XFRM
394 const struct nft_meta *priv = nft_expr_priv(expr);
395 unsigned int hooks;
396
397 if (priv->key != NFT_META_SECPATH)
398 return 0;
399
400 switch (ctx->family) {
401 case NFPROTO_NETDEV:
402 hooks = 1 << NF_NETDEV_INGRESS;
403 break;
404 case NFPROTO_IPV4:
405 case NFPROTO_IPV6:
406 case NFPROTO_INET:
407 hooks = (1 << NF_INET_PRE_ROUTING) |
408 (1 << NF_INET_LOCAL_IN) |
409 (1 << NF_INET_FORWARD);
410 break;
411 default:
412 return -EOPNOTSUPP;
413 }
414
415 return nft_chain_validate_hooks(ctx->chain, hooks);
416#else
417 return 0;
418#endif
419}
420
421int nft_meta_set_validate(const struct nft_ctx *ctx,
422 const struct nft_expr *expr,
423 const struct nft_data **data)
424{
425 struct nft_meta *priv = nft_expr_priv(expr);
426 unsigned int hooks;
427
428 if (priv->key != NFT_META_PKTTYPE)
429 return 0;
430
431 switch (ctx->family) {
432 case NFPROTO_BRIDGE:
433 hooks = 1 << NF_BR_PRE_ROUTING;
434 break;
435 case NFPROTO_NETDEV:
436 hooks = 1 << NF_NETDEV_INGRESS;
437 break;
438 case NFPROTO_IPV4:
439 case NFPROTO_IPV6:
440 case NFPROTO_INET:
441 hooks = 1 << NF_INET_PRE_ROUTING;
442 break;
443 default:
444 return -EOPNOTSUPP;
445 }
446
447 return nft_chain_validate_hooks(ctx->chain, hooks);
448}
449EXPORT_SYMBOL_GPL(nft_meta_set_validate);
450
451int nft_meta_set_init(const struct nft_ctx *ctx,
452 const struct nft_expr *expr,
453 const struct nlattr * const tb[])
454{
455 struct nft_meta *priv = nft_expr_priv(expr);
456 unsigned int len;
457 int err;
458
459 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
460 switch (priv->key) {
461 case NFT_META_MARK:
462 case NFT_META_PRIORITY:
463#ifdef CONFIG_NETWORK_SECMARK
464 case NFT_META_SECMARK:
465#endif
466 len = sizeof(u32);
467 break;
468 case NFT_META_NFTRACE:
469 len = sizeof(u8);
470 break;
471 case NFT_META_PKTTYPE:
472 len = sizeof(u8);
473 break;
474 default:
475 return -EOPNOTSUPP;
476 }
477
478 priv->sreg = nft_parse_register(tb[NFTA_META_SREG]);
479 err = nft_validate_register_load(priv->sreg, len);
480 if (err < 0)
481 return err;
482
483 if (priv->key == NFT_META_NFTRACE)
484 static_branch_inc(&nft_trace_enabled);
485
486 return 0;
487}
488EXPORT_SYMBOL_GPL(nft_meta_set_init);
489
490int nft_meta_get_dump(struct sk_buff *skb,
491 const struct nft_expr *expr)
492{
493 const struct nft_meta *priv = nft_expr_priv(expr);
494
495 if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
496 goto nla_put_failure;
497 if (nft_dump_register(skb, NFTA_META_DREG, priv->dreg))
498 goto nla_put_failure;
499 return 0;
500
501nla_put_failure:
502 return -1;
503}
504EXPORT_SYMBOL_GPL(nft_meta_get_dump);
505
506int nft_meta_set_dump(struct sk_buff *skb, const struct nft_expr *expr)
507{
508 const struct nft_meta *priv = nft_expr_priv(expr);
509
510 if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
511 goto nla_put_failure;
512 if (nft_dump_register(skb, NFTA_META_SREG, priv->sreg))
513 goto nla_put_failure;
514
515 return 0;
516
517nla_put_failure:
518 return -1;
519}
520EXPORT_SYMBOL_GPL(nft_meta_set_dump);
521
522void nft_meta_set_destroy(const struct nft_ctx *ctx,
523 const struct nft_expr *expr)
524{
525 const struct nft_meta *priv = nft_expr_priv(expr);
526
527 if (priv->key == NFT_META_NFTRACE)
528 static_branch_dec(&nft_trace_enabled);
529}
530EXPORT_SYMBOL_GPL(nft_meta_set_destroy);
531
532static int nft_meta_get_offload(struct nft_offload_ctx *ctx,
533 struct nft_flow_rule *flow,
534 const struct nft_expr *expr)
535{
536 const struct nft_meta *priv = nft_expr_priv(expr);
537 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
538
539 switch (priv->key) {
540 case NFT_META_PROTOCOL:
541 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, n_proto,
542 sizeof(__u16), reg);
543 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
544 break;
545 case NFT_META_L4PROTO:
546 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
547 sizeof(__u8), reg);
548 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
549 break;
550 default:
551 return -EOPNOTSUPP;
552 }
553
554 return 0;
555}
556
557static const struct nft_expr_ops nft_meta_get_ops = {
558 .type = &nft_meta_type,
559 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
560 .eval = nft_meta_get_eval,
561 .init = nft_meta_get_init,
562 .dump = nft_meta_get_dump,
563 .validate = nft_meta_get_validate,
564 .offload = nft_meta_get_offload,
565};
566
567static const struct nft_expr_ops nft_meta_set_ops = {
568 .type = &nft_meta_type,
569 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
570 .eval = nft_meta_set_eval,
571 .init = nft_meta_set_init,
572 .destroy = nft_meta_set_destroy,
573 .dump = nft_meta_set_dump,
574 .validate = nft_meta_set_validate,
575};
576
577static const struct nft_expr_ops *
578nft_meta_select_ops(const struct nft_ctx *ctx,
579 const struct nlattr * const tb[])
580{
581 if (tb[NFTA_META_KEY] == NULL)
582 return ERR_PTR(-EINVAL);
583
584 if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
585 return ERR_PTR(-EINVAL);
586
587#if IS_ENABLED(CONFIG_NF_TABLES_BRIDGE) && IS_MODULE(CONFIG_NFT_BRIDGE_META)
588 if (ctx->family == NFPROTO_BRIDGE)
589 return ERR_PTR(-EAGAIN);
590#endif
591 if (tb[NFTA_META_DREG])
592 return &nft_meta_get_ops;
593
594 if (tb[NFTA_META_SREG])
595 return &nft_meta_set_ops;
596
597 return ERR_PTR(-EINVAL);
598}
599
600struct nft_expr_type nft_meta_type __read_mostly = {
601 .name = "meta",
602 .select_ops = nft_meta_select_ops,
603 .policy = nft_meta_policy,
604 .maxattr = NFTA_META_MAX,
605 .owner = THIS_MODULE,
606};
607
608#ifdef CONFIG_NETWORK_SECMARK
609struct nft_secmark {
610 u32 secid;
611 char *ctx;
612};
613
614static const struct nla_policy nft_secmark_policy[NFTA_SECMARK_MAX + 1] = {
615 [NFTA_SECMARK_CTX] = { .type = NLA_STRING, .len = NFT_SECMARK_CTX_MAXLEN },
616};
617
618static int nft_secmark_compute_secid(struct nft_secmark *priv)
619{
620 u32 tmp_secid = 0;
621 int err;
622
623 err = security_secctx_to_secid(priv->ctx, strlen(priv->ctx), &tmp_secid);
624 if (err)
625 return err;
626
627 if (!tmp_secid)
628 return -ENOENT;
629
630 err = security_secmark_relabel_packet(tmp_secid);
631 if (err)
632 return err;
633
634 priv->secid = tmp_secid;
635 return 0;
636}
637
638static void nft_secmark_obj_eval(struct nft_object *obj, struct nft_regs *regs,
639 const struct nft_pktinfo *pkt)
640{
641 const struct nft_secmark *priv = nft_obj_data(obj);
642 struct sk_buff *skb = pkt->skb;
643
644 skb->secmark = priv->secid;
645}
646
647static int nft_secmark_obj_init(const struct nft_ctx *ctx,
648 const struct nlattr * const tb[],
649 struct nft_object *obj)
650{
651 struct nft_secmark *priv = nft_obj_data(obj);
652 int err;
653
654 if (tb[NFTA_SECMARK_CTX] == NULL)
655 return -EINVAL;
656
657 priv->ctx = nla_strdup(tb[NFTA_SECMARK_CTX], GFP_KERNEL);
658 if (!priv->ctx)
659 return -ENOMEM;
660
661 err = nft_secmark_compute_secid(priv);
662 if (err) {
663 kfree(priv->ctx);
664 return err;
665 }
666
667 security_secmark_refcount_inc();
668
669 return 0;
670}
671
672static int nft_secmark_obj_dump(struct sk_buff *skb, struct nft_object *obj,
673 bool reset)
674{
675 struct nft_secmark *priv = nft_obj_data(obj);
676 int err;
677
678 if (nla_put_string(skb, NFTA_SECMARK_CTX, priv->ctx))
679 return -1;
680
681 if (reset) {
682 err = nft_secmark_compute_secid(priv);
683 if (err)
684 return err;
685 }
686
687 return 0;
688}
689
690static void nft_secmark_obj_destroy(const struct nft_ctx *ctx, struct nft_object *obj)
691{
692 struct nft_secmark *priv = nft_obj_data(obj);
693
694 security_secmark_refcount_dec();
695
696 kfree(priv->ctx);
697}
698
699static const struct nft_object_ops nft_secmark_obj_ops = {
700 .type = &nft_secmark_obj_type,
701 .size = sizeof(struct nft_secmark),
702 .init = nft_secmark_obj_init,
703 .eval = nft_secmark_obj_eval,
704 .dump = nft_secmark_obj_dump,
705 .destroy = nft_secmark_obj_destroy,
706};
707struct nft_object_type nft_secmark_obj_type __read_mostly = {
708 .type = NFT_OBJECT_SECMARK,
709 .ops = &nft_secmark_obj_ops,
710 .maxattr = NFTA_SECMARK_MAX,
711 .policy = nft_secmark_policy,
712 .owner = THIS_MODULE,
713};
714#endif
715
