1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
4 * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
5 *
6 * Development of this code funded by Astaro AG (http://www.astaro.com/)
7 */
8
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/netlink.h>
13 #include <linux/netfilter.h>
14 #include <linux/netfilter/nf_tables.h>
15 #include <net/netfilter/nf_tables_core.h>
16 #include <net/netfilter/nf_conntrack.h>
17 #include <net/netfilter/nf_conntrack_acct.h>
18 #include <net/netfilter/nf_conntrack_tuple.h>
19 #include <net/netfilter/nf_conntrack_helper.h>
20 #include <net/netfilter/nf_conntrack_ecache.h>
21 #include <net/netfilter/nf_conntrack_labels.h>
22 #include <net/netfilter/nf_conntrack_timeout.h>
23 #include <net/netfilter/nf_conntrack_l4proto.h>
24 #include <net/netfilter/nf_conntrack_expect.h>
25
26 struct nft_ct_helper_obj {
27 struct nf_conntrack_helper *helper4;
28 struct nf_conntrack_helper *helper6;
29 u8 l4proto;
30 };
31
32 #ifdef CONFIG_NF_CONNTRACK_ZONES
33 static DEFINE_PER_CPU(struct nf_conn *, nft_ct_pcpu_template);
34 static unsigned int nft_ct_pcpu_template_refcnt __read_mostly;
35 static DEFINE_MUTEX(nft_ct_pcpu_mutex);
36 #endif
37
nft_ct_get_eval_counter(const struct nf_conn_counter * c,enum nft_ct_keys k,enum ip_conntrack_dir d)38 static u64 nft_ct_get_eval_counter(const struct nf_conn_counter *c,
39 enum nft_ct_keys k,
40 enum ip_conntrack_dir d)
41 {
42 if (d < IP_CT_DIR_MAX)
43 return k == NFT_CT_BYTES ? atomic64_read(&c[d].bytes) :
44 atomic64_read(&c[d].packets);
45
46 return nft_ct_get_eval_counter(c, k, IP_CT_DIR_ORIGINAL) +
47 nft_ct_get_eval_counter(c, k, IP_CT_DIR_REPLY);
48 }
49
nft_ct_get_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)50 static void nft_ct_get_eval(const struct nft_expr *expr,
51 struct nft_regs *regs,
52 const struct nft_pktinfo *pkt)
53 {
54 const struct nft_ct *priv = nft_expr_priv(expr);
55 u32 *dest = ®s->data[priv->dreg];
56 enum ip_conntrack_info ctinfo;
57 const struct nf_conn *ct;
58 const struct nf_conn_help *help;
59 const struct nf_conntrack_tuple *tuple;
60 const struct nf_conntrack_helper *helper;
61 unsigned int state;
62
63 ct = nf_ct_get(pkt->skb, &ctinfo);
64
65 switch (priv->key) {
66 case NFT_CT_STATE:
67 if (ct)
68 state = NF_CT_STATE_BIT(ctinfo);
69 else if (ctinfo == IP_CT_UNTRACKED)
70 state = NF_CT_STATE_UNTRACKED_BIT;
71 else
72 state = NF_CT_STATE_INVALID_BIT;
73 *dest = state;
74 return;
75 default:
76 break;
77 }
78
79 if (ct == NULL)
80 goto err;
81
82 switch (priv->key) {
83 case NFT_CT_DIRECTION:
84 nft_reg_store8(dest, CTINFO2DIR(ctinfo));
85 return;
86 case NFT_CT_STATUS:
87 *dest = ct->status;
88 return;
89 #ifdef CONFIG_NF_CONNTRACK_MARK
90 case NFT_CT_MARK:
91 *dest = READ_ONCE(ct->mark);
92 return;
93 #endif
94 #ifdef CONFIG_NF_CONNTRACK_SECMARK
95 case NFT_CT_SECMARK:
96 *dest = ct->secmark;
97 return;
98 #endif
99 case NFT_CT_EXPIRATION:
100 *dest = jiffies_to_msecs(nf_ct_expires(ct));
101 return;
102 case NFT_CT_HELPER:
103 if (ct->master == NULL)
104 goto err;
105 help = nfct_help(ct->master);
106 if (help == NULL)
107 goto err;
108 helper = rcu_dereference(help->helper);
109 if (helper == NULL)
110 goto err;
111 strscpy_pad((char *)dest, helper->name, NF_CT_HELPER_NAME_LEN);
112 return;
113 #ifdef CONFIG_NF_CONNTRACK_LABELS
114 case NFT_CT_LABELS: {
115 struct nf_conn_labels *labels = nf_ct_labels_find(ct);
116
117 if (labels)
118 memcpy(dest, labels->bits, NF_CT_LABELS_MAX_SIZE);
119 else
120 memset(dest, 0, NF_CT_LABELS_MAX_SIZE);
121 return;
122 }
123 #endif
124 case NFT_CT_BYTES:
125 case NFT_CT_PKTS: {
126 const struct nf_conn_acct *acct = nf_conn_acct_find(ct);
127 u64 count = 0;
128
129 if (acct)
130 count = nft_ct_get_eval_counter(acct->counter,
131 priv->key, priv->dir);
132 memcpy(dest, &count, sizeof(count));
133 return;
134 }
135 case NFT_CT_AVGPKT: {
136 const struct nf_conn_acct *acct = nf_conn_acct_find(ct);
137 u64 avgcnt = 0, bcnt = 0, pcnt = 0;
138
139 if (acct) {
140 pcnt = nft_ct_get_eval_counter(acct->counter,
141 NFT_CT_PKTS, priv->dir);
142 bcnt = nft_ct_get_eval_counter(acct->counter,
143 NFT_CT_BYTES, priv->dir);
144 if (pcnt != 0)
145 avgcnt = div64_u64(bcnt, pcnt);
146 }
147
148 memcpy(dest, &avgcnt, sizeof(avgcnt));
149 return;
150 }
151 case NFT_CT_L3PROTOCOL:
152 nft_reg_store8(dest, nf_ct_l3num(ct));
153 return;
154 case NFT_CT_PROTOCOL:
155 nft_reg_store8(dest, nf_ct_protonum(ct));
156 return;
157 #ifdef CONFIG_NF_CONNTRACK_ZONES
158 case NFT_CT_ZONE: {
159 const struct nf_conntrack_zone *zone = nf_ct_zone(ct);
160 u16 zoneid;
161
162 if (priv->dir < IP_CT_DIR_MAX)
163 zoneid = nf_ct_zone_id(zone, priv->dir);
164 else
165 zoneid = zone->id;
166
167 nft_reg_store16(dest, zoneid);
168 return;
169 }
170 #endif
171 case NFT_CT_ID:
172 *dest = nf_ct_get_id(ct);
173 return;
174 default:
175 break;
176 }
177
178 tuple = &ct->tuplehash[priv->dir].tuple;
179 switch (priv->key) {
180 case NFT_CT_SRC:
181 memcpy(dest, tuple->src.u3.all,
182 nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16);
183 return;
184 case NFT_CT_DST:
185 memcpy(dest, tuple->dst.u3.all,
186 nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16);
187 return;
188 case NFT_CT_PROTO_SRC:
189 nft_reg_store16(dest, (__force u16)tuple->src.u.all);
190 return;
191 case NFT_CT_PROTO_DST:
192 nft_reg_store16(dest, (__force u16)tuple->dst.u.all);
193 return;
194 case NFT_CT_SRC_IP:
195 if (nf_ct_l3num(ct) != NFPROTO_IPV4)
196 goto err;
197 *dest = (__force __u32)tuple->src.u3.ip;
198 return;
199 case NFT_CT_DST_IP:
200 if (nf_ct_l3num(ct) != NFPROTO_IPV4)
201 goto err;
202 *dest = (__force __u32)tuple->dst.u3.ip;
203 return;
204 case NFT_CT_SRC_IP6:
205 if (nf_ct_l3num(ct) != NFPROTO_IPV6)
206 goto err;
207 memcpy(dest, tuple->src.u3.ip6, sizeof(struct in6_addr));
208 return;
209 case NFT_CT_DST_IP6:
210 if (nf_ct_l3num(ct) != NFPROTO_IPV6)
211 goto err;
212 memcpy(dest, tuple->dst.u3.ip6, sizeof(struct in6_addr));
213 return;
214 default:
215 break;
216 }
217 return;
218 err:
219 regs->verdict.code = NFT_BREAK;
220 }
221
222 #ifdef CONFIG_NF_CONNTRACK_ZONES
nft_ct_set_zone_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)223 static void nft_ct_set_zone_eval(const struct nft_expr *expr,
224 struct nft_regs *regs,
225 const struct nft_pktinfo *pkt)
226 {
227 struct nf_conntrack_zone zone = { .dir = NF_CT_DEFAULT_ZONE_DIR };
228 const struct nft_ct *priv = nft_expr_priv(expr);
229 struct sk_buff *skb = pkt->skb;
230 enum ip_conntrack_info ctinfo;
231 u16 value = nft_reg_load16(®s->data[priv->sreg]);
232 struct nf_conn *ct;
233
234 ct = nf_ct_get(skb, &ctinfo);
235 if (ct) /* already tracked */
236 return;
237
238 zone.id = value;
239
240 switch (priv->dir) {
241 case IP_CT_DIR_ORIGINAL:
242 zone.dir = NF_CT_ZONE_DIR_ORIG;
243 break;
244 case IP_CT_DIR_REPLY:
245 zone.dir = NF_CT_ZONE_DIR_REPL;
246 break;
247 default:
248 break;
249 }
250
251 ct = this_cpu_read(nft_ct_pcpu_template);
252
253 if (likely(refcount_read(&ct->ct_general.use) == 1)) {
254 refcount_inc(&ct->ct_general.use);
255 nf_ct_zone_add(ct, &zone);
256 } else {
257 /* previous skb got queued to userspace, allocate temporary
258 * one until percpu template can be reused.
259 */
260 ct = nf_ct_tmpl_alloc(nft_net(pkt), &zone, GFP_ATOMIC);
261 if (!ct) {
262 regs->verdict.code = NF_DROP;
263 return;
264 }
265 __set_bit(IPS_CONFIRMED_BIT, &ct->status);
266 }
267
268 nf_ct_set(skb, ct, IP_CT_NEW);
269 }
270 #endif
271
nft_ct_set_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)272 static void nft_ct_set_eval(const struct nft_expr *expr,
273 struct nft_regs *regs,
274 const struct nft_pktinfo *pkt)
275 {
276 const struct nft_ct *priv = nft_expr_priv(expr);
277 struct sk_buff *skb = pkt->skb;
278 #if defined(CONFIG_NF_CONNTRACK_MARK) || defined(CONFIG_NF_CONNTRACK_SECMARK)
279 u32 value = regs->data[priv->sreg];
280 #endif
281 enum ip_conntrack_info ctinfo;
282 struct nf_conn *ct;
283
284 ct = nf_ct_get(skb, &ctinfo);
285 if (ct == NULL || nf_ct_is_template(ct))
286 return;
287
288 switch (priv->key) {
289 #ifdef CONFIG_NF_CONNTRACK_MARK
290 case NFT_CT_MARK:
291 if (READ_ONCE(ct->mark) != value) {
292 WRITE_ONCE(ct->mark, value);
293 nf_conntrack_event_cache(IPCT_MARK, ct);
294 }
295 break;
296 #endif
297 #ifdef CONFIG_NF_CONNTRACK_SECMARK
298 case NFT_CT_SECMARK:
299 if (ct->secmark != value) {
300 ct->secmark = value;
301 nf_conntrack_event_cache(IPCT_SECMARK, ct);
302 }
303 break;
304 #endif
305 #ifdef CONFIG_NF_CONNTRACK_LABELS
306 case NFT_CT_LABELS:
307 nf_connlabels_replace(ct,
308 ®s->data[priv->sreg],
309 ®s->data[priv->sreg],
310 NF_CT_LABELS_MAX_SIZE / sizeof(u32));
311 break;
312 #endif
313 #ifdef CONFIG_NF_CONNTRACK_EVENTS
314 case NFT_CT_EVENTMASK: {
315 struct nf_conntrack_ecache *e = nf_ct_ecache_find(ct);
316 u32 ctmask = regs->data[priv->sreg];
317
318 if (e) {
319 if (e->ctmask != ctmask)
320 e->ctmask = ctmask;
321 break;
322 }
323
324 if (ctmask && !nf_ct_is_confirmed(ct))
325 nf_ct_ecache_ext_add(ct, ctmask, 0, GFP_ATOMIC);
326 break;
327 }
328 #endif
329 default:
330 break;
331 }
332 }
333
334 static const struct nla_policy nft_ct_policy[NFTA_CT_MAX + 1] = {
335 [NFTA_CT_DREG] = { .type = NLA_U32 },
336 [NFTA_CT_KEY] = NLA_POLICY_MAX(NLA_BE32, 255),
337 [NFTA_CT_DIRECTION] = { .type = NLA_U8 },
338 [NFTA_CT_SREG] = { .type = NLA_U32 },
339 };
340
341 #ifdef CONFIG_NF_CONNTRACK_ZONES
nft_ct_tmpl_put_pcpu(void)342 static void nft_ct_tmpl_put_pcpu(void)
343 {
344 struct nf_conn *ct;
345 int cpu;
346
347 for_each_possible_cpu(cpu) {
348 ct = per_cpu(nft_ct_pcpu_template, cpu);
349 if (!ct)
350 break;
351 nf_ct_put(ct);
352 per_cpu(nft_ct_pcpu_template, cpu) = NULL;
353 }
354 }
355
nft_ct_tmpl_alloc_pcpu(void)356 static bool nft_ct_tmpl_alloc_pcpu(void)
357 {
358 struct nf_conntrack_zone zone = { .id = 0 };
359 struct nf_conn *tmp;
360 int cpu;
361
362 if (nft_ct_pcpu_template_refcnt)
363 return true;
364
365 for_each_possible_cpu(cpu) {
366 tmp = nf_ct_tmpl_alloc(&init_net, &zone, GFP_KERNEL);
367 if (!tmp) {
368 nft_ct_tmpl_put_pcpu();
369 return false;
370 }
371
372 __set_bit(IPS_CONFIRMED_BIT, &tmp->status);
373 per_cpu(nft_ct_pcpu_template, cpu) = tmp;
374 }
375
376 return true;
377 }
378 #endif
379
nft_ct_get_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])380 static int nft_ct_get_init(const struct nft_ctx *ctx,
381 const struct nft_expr *expr,
382 const struct nlattr * const tb[])
383 {
384 struct nft_ct *priv = nft_expr_priv(expr);
385 unsigned int len;
386 int err;
387
388 priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
389 priv->dir = IP_CT_DIR_MAX;
390 switch (priv->key) {
391 case NFT_CT_DIRECTION:
392 if (tb[NFTA_CT_DIRECTION] != NULL)
393 return -EINVAL;
394 len = sizeof(u8);
395 break;
396 case NFT_CT_STATE:
397 case NFT_CT_STATUS:
398 #ifdef CONFIG_NF_CONNTRACK_MARK
399 case NFT_CT_MARK:
400 #endif
401 #ifdef CONFIG_NF_CONNTRACK_SECMARK
402 case NFT_CT_SECMARK:
403 #endif
404 case NFT_CT_EXPIRATION:
405 if (tb[NFTA_CT_DIRECTION] != NULL)
406 return -EINVAL;
407 len = sizeof(u32);
408 break;
409 #ifdef CONFIG_NF_CONNTRACK_LABELS
410 case NFT_CT_LABELS:
411 if (tb[NFTA_CT_DIRECTION] != NULL)
412 return -EINVAL;
413 len = NF_CT_LABELS_MAX_SIZE;
414 break;
415 #endif
416 case NFT_CT_HELPER:
417 if (tb[NFTA_CT_DIRECTION] != NULL)
418 return -EINVAL;
419 len = NF_CT_HELPER_NAME_LEN;
420 break;
421
422 case NFT_CT_L3PROTOCOL:
423 case NFT_CT_PROTOCOL:
424 /* For compatibility, do not report error if NFTA_CT_DIRECTION
425 * attribute is specified.
426 */
427 len = sizeof(u8);
428 break;
429 case NFT_CT_SRC:
430 case NFT_CT_DST:
431 if (tb[NFTA_CT_DIRECTION] == NULL)
432 return -EINVAL;
433
434 switch (ctx->family) {
435 case NFPROTO_IPV4:
436 len = sizeof_field(struct nf_conntrack_tuple,
437 src.u3.ip);
438 break;
439 case NFPROTO_IPV6:
440 case NFPROTO_INET:
441 len = sizeof_field(struct nf_conntrack_tuple,
442 src.u3.ip6);
443 break;
444 default:
445 return -EAFNOSUPPORT;
446 }
447 break;
448 case NFT_CT_SRC_IP:
449 case NFT_CT_DST_IP:
450 if (tb[NFTA_CT_DIRECTION] == NULL)
451 return -EINVAL;
452
453 len = sizeof_field(struct nf_conntrack_tuple, src.u3.ip);
454 break;
455 case NFT_CT_SRC_IP6:
456 case NFT_CT_DST_IP6:
457 if (tb[NFTA_CT_DIRECTION] == NULL)
458 return -EINVAL;
459
460 len = sizeof_field(struct nf_conntrack_tuple, src.u3.ip6);
461 break;
462 case NFT_CT_PROTO_SRC:
463 case NFT_CT_PROTO_DST:
464 if (tb[NFTA_CT_DIRECTION] == NULL)
465 return -EINVAL;
466 len = sizeof_field(struct nf_conntrack_tuple, src.u.all);
467 break;
468 case NFT_CT_BYTES:
469 case NFT_CT_PKTS:
470 case NFT_CT_AVGPKT:
471 len = sizeof(u64);
472 break;
473 #ifdef CONFIG_NF_CONNTRACK_ZONES
474 case NFT_CT_ZONE:
475 len = sizeof(u16);
476 break;
477 #endif
478 case NFT_CT_ID:
479 if (tb[NFTA_CT_DIRECTION])
480 return -EINVAL;
481
482 len = sizeof(u32);
483 break;
484 default:
485 return -EOPNOTSUPP;
486 }
487
488 if (tb[NFTA_CT_DIRECTION] != NULL) {
489 priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]);
490 switch (priv->dir) {
491 case IP_CT_DIR_ORIGINAL:
492 case IP_CT_DIR_REPLY:
493 break;
494 default:
495 return -EINVAL;
496 }
497 }
498
499 priv->len = len;
500 err = nft_parse_register_store(ctx, tb[NFTA_CT_DREG], &priv->dreg, NULL,
501 NFT_DATA_VALUE, len);
502 if (err < 0)
503 return err;
504
505 err = nf_ct_netns_get(ctx->net, ctx->family);
506 if (err < 0)
507 return err;
508
509 if (priv->key == NFT_CT_BYTES ||
510 priv->key == NFT_CT_PKTS ||
511 priv->key == NFT_CT_AVGPKT)
512 nf_ct_set_acct(ctx->net, true);
513
514 return 0;
515 }
516
__nft_ct_set_destroy(const struct nft_ctx * ctx,struct nft_ct * priv)517 static void __nft_ct_set_destroy(const struct nft_ctx *ctx, struct nft_ct *priv)
518 {
519 switch (priv->key) {
520 #ifdef CONFIG_NF_CONNTRACK_LABELS
521 case NFT_CT_LABELS:
522 nf_connlabels_put(ctx->net);
523 break;
524 #endif
525 #ifdef CONFIG_NF_CONNTRACK_ZONES
526 case NFT_CT_ZONE:
527 mutex_lock(&nft_ct_pcpu_mutex);
528 if (--nft_ct_pcpu_template_refcnt == 0)
529 nft_ct_tmpl_put_pcpu();
530 mutex_unlock(&nft_ct_pcpu_mutex);
531 break;
532 #endif
533 default:
534 break;
535 }
536 }
537
nft_ct_set_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])538 static int nft_ct_set_init(const struct nft_ctx *ctx,
539 const struct nft_expr *expr,
540 const struct nlattr * const tb[])
541 {
542 struct nft_ct *priv = nft_expr_priv(expr);
543 unsigned int len;
544 int err;
545
546 priv->dir = IP_CT_DIR_MAX;
547 priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
548 switch (priv->key) {
549 #ifdef CONFIG_NF_CONNTRACK_MARK
550 case NFT_CT_MARK:
551 if (tb[NFTA_CT_DIRECTION])
552 return -EINVAL;
553 len = sizeof_field(struct nf_conn, mark);
554 break;
555 #endif
556 #ifdef CONFIG_NF_CONNTRACK_LABELS
557 case NFT_CT_LABELS:
558 if (tb[NFTA_CT_DIRECTION])
559 return -EINVAL;
560 len = NF_CT_LABELS_MAX_SIZE;
561 err = nf_connlabels_get(ctx->net, (len * BITS_PER_BYTE) - 1);
562 if (err)
563 return err;
564 break;
565 #endif
566 #ifdef CONFIG_NF_CONNTRACK_ZONES
567 case NFT_CT_ZONE:
568 mutex_lock(&nft_ct_pcpu_mutex);
569 if (!nft_ct_tmpl_alloc_pcpu()) {
570 mutex_unlock(&nft_ct_pcpu_mutex);
571 return -ENOMEM;
572 }
573 nft_ct_pcpu_template_refcnt++;
574 mutex_unlock(&nft_ct_pcpu_mutex);
575 len = sizeof(u16);
576 break;
577 #endif
578 #ifdef CONFIG_NF_CONNTRACK_EVENTS
579 case NFT_CT_EVENTMASK:
580 if (tb[NFTA_CT_DIRECTION])
581 return -EINVAL;
582 len = sizeof(u32);
583 break;
584 #endif
585 #ifdef CONFIG_NF_CONNTRACK_SECMARK
586 case NFT_CT_SECMARK:
587 if (tb[NFTA_CT_DIRECTION])
588 return -EINVAL;
589 len = sizeof(u32);
590 break;
591 #endif
592 default:
593 return -EOPNOTSUPP;
594 }
595
596 if (tb[NFTA_CT_DIRECTION]) {
597 priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]);
598 switch (priv->dir) {
599 case IP_CT_DIR_ORIGINAL:
600 case IP_CT_DIR_REPLY:
601 break;
602 default:
603 err = -EINVAL;
604 goto err1;
605 }
606 }
607
608 priv->len = len;
609 err = nft_parse_register_load(ctx, tb[NFTA_CT_SREG], &priv->sreg, len);
610 if (err < 0)
611 goto err1;
612
613 err = nf_ct_netns_get(ctx->net, ctx->family);
614 if (err < 0)
615 goto err1;
616
617 return 0;
618
619 err1:
620 __nft_ct_set_destroy(ctx, priv);
621 return err;
622 }
623
nft_ct_get_destroy(const struct nft_ctx * ctx,const struct nft_expr * expr)624 static void nft_ct_get_destroy(const struct nft_ctx *ctx,
625 const struct nft_expr *expr)
626 {
627 nf_ct_netns_put(ctx->net, ctx->family);
628 }
629
nft_ct_set_destroy(const struct nft_ctx * ctx,const struct nft_expr * expr)630 static void nft_ct_set_destroy(const struct nft_ctx *ctx,
631 const struct nft_expr *expr)
632 {
633 struct nft_ct *priv = nft_expr_priv(expr);
634
635 __nft_ct_set_destroy(ctx, priv);
636 nf_ct_netns_put(ctx->net, ctx->family);
637 }
638
nft_ct_get_dump(struct sk_buff * skb,const struct nft_expr * expr,bool reset)639 static int nft_ct_get_dump(struct sk_buff *skb,
640 const struct nft_expr *expr, bool reset)
641 {
642 const struct nft_ct *priv = nft_expr_priv(expr);
643
644 if (nft_dump_register(skb, NFTA_CT_DREG, priv->dreg))
645 goto nla_put_failure;
646 if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key)))
647 goto nla_put_failure;
648
649 switch (priv->key) {
650 case NFT_CT_SRC:
651 case NFT_CT_DST:
652 case NFT_CT_SRC_IP:
653 case NFT_CT_DST_IP:
654 case NFT_CT_SRC_IP6:
655 case NFT_CT_DST_IP6:
656 case NFT_CT_PROTO_SRC:
657 case NFT_CT_PROTO_DST:
658 if (nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir))
659 goto nla_put_failure;
660 break;
661 case NFT_CT_BYTES:
662 case NFT_CT_PKTS:
663 case NFT_CT_AVGPKT:
664 case NFT_CT_ZONE:
665 if (priv->dir < IP_CT_DIR_MAX &&
666 nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir))
667 goto nla_put_failure;
668 break;
669 default:
670 break;
671 }
672
673 return 0;
674
675 nla_put_failure:
676 return -1;
677 }
678
nft_ct_get_reduce(struct nft_regs_track * track,const struct nft_expr * expr)679 static bool nft_ct_get_reduce(struct nft_regs_track *track,
680 const struct nft_expr *expr)
681 {
682 const struct nft_ct *priv = nft_expr_priv(expr);
683 const struct nft_ct *ct;
684
685 if (!nft_reg_track_cmp(track, expr, priv->dreg)) {
686 nft_reg_track_update(track, expr, priv->dreg, priv->len);
687 return false;
688 }
689
690 ct = nft_expr_priv(track->regs[priv->dreg].selector);
691 if (priv->key != ct->key) {
692 nft_reg_track_update(track, expr, priv->dreg, priv->len);
693 return false;
694 }
695
696 if (!track->regs[priv->dreg].bitwise)
697 return true;
698
699 return nft_expr_reduce_bitwise(track, expr);
700 }
701
nft_ct_set_dump(struct sk_buff * skb,const struct nft_expr * expr,bool reset)702 static int nft_ct_set_dump(struct sk_buff *skb,
703 const struct nft_expr *expr, bool reset)
704 {
705 const struct nft_ct *priv = nft_expr_priv(expr);
706
707 if (nft_dump_register(skb, NFTA_CT_SREG, priv->sreg))
708 goto nla_put_failure;
709 if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key)))
710 goto nla_put_failure;
711
712 switch (priv->key) {
713 case NFT_CT_ZONE:
714 if (priv->dir < IP_CT_DIR_MAX &&
715 nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir))
716 goto nla_put_failure;
717 break;
718 default:
719 break;
720 }
721
722 return 0;
723
724 nla_put_failure:
725 return -1;
726 }
727
728 static struct nft_expr_type nft_ct_type;
729 static const struct nft_expr_ops nft_ct_get_ops = {
730 .type = &nft_ct_type,
731 .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
732 .eval = nft_ct_get_eval,
733 .init = nft_ct_get_init,
734 .destroy = nft_ct_get_destroy,
735 .dump = nft_ct_get_dump,
736 .reduce = nft_ct_get_reduce,
737 };
738
nft_ct_set_reduce(struct nft_regs_track * track,const struct nft_expr * expr)739 static bool nft_ct_set_reduce(struct nft_regs_track *track,
740 const struct nft_expr *expr)
741 {
742 int i;
743
744 for (i = 0; i < NFT_REG32_NUM; i++) {
745 if (!track->regs[i].selector)
746 continue;
747
748 if (track->regs[i].selector->ops != &nft_ct_get_ops)
749 continue;
750
751 __nft_reg_track_cancel(track, i);
752 }
753
754 return false;
755 }
756
757 #ifdef CONFIG_MITIGATION_RETPOLINE
758 static const struct nft_expr_ops nft_ct_get_fast_ops = {
759 .type = &nft_ct_type,
760 .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
761 .eval = nft_ct_get_fast_eval,
762 .init = nft_ct_get_init,
763 .destroy = nft_ct_get_destroy,
764 .dump = nft_ct_get_dump,
765 .reduce = nft_ct_set_reduce,
766 };
767 #endif
768
769 static const struct nft_expr_ops nft_ct_set_ops = {
770 .type = &nft_ct_type,
771 .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
772 .eval = nft_ct_set_eval,
773 .init = nft_ct_set_init,
774 .destroy = nft_ct_set_destroy,
775 .dump = nft_ct_set_dump,
776 .reduce = nft_ct_set_reduce,
777 };
778
779 #ifdef CONFIG_NF_CONNTRACK_ZONES
780 static const struct nft_expr_ops nft_ct_set_zone_ops = {
781 .type = &nft_ct_type,
782 .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
783 .eval = nft_ct_set_zone_eval,
784 .init = nft_ct_set_init,
785 .destroy = nft_ct_set_destroy,
786 .dump = nft_ct_set_dump,
787 .reduce = nft_ct_set_reduce,
788 };
789 #endif
790
791 static const struct nft_expr_ops *
nft_ct_select_ops(const struct nft_ctx * ctx,const struct nlattr * const tb[])792 nft_ct_select_ops(const struct nft_ctx *ctx,
793 const struct nlattr * const tb[])
794 {
795 if (tb[NFTA_CT_KEY] == NULL)
796 return ERR_PTR(-EINVAL);
797
798 if (tb[NFTA_CT_DREG] && tb[NFTA_CT_SREG])
799 return ERR_PTR(-EINVAL);
800
801 if (tb[NFTA_CT_DREG]) {
802 #ifdef CONFIG_MITIGATION_RETPOLINE
803 u32 k = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
804
805 switch (k) {
806 case NFT_CT_STATE:
807 case NFT_CT_DIRECTION:
808 case NFT_CT_STATUS:
809 case NFT_CT_MARK:
810 case NFT_CT_SECMARK:
811 return &nft_ct_get_fast_ops;
812 }
813 #endif
814 return &nft_ct_get_ops;
815 }
816
817 if (tb[NFTA_CT_SREG]) {
818 #ifdef CONFIG_NF_CONNTRACK_ZONES
819 if (nla_get_be32(tb[NFTA_CT_KEY]) == htonl(NFT_CT_ZONE))
820 return &nft_ct_set_zone_ops;
821 #endif
822 return &nft_ct_set_ops;
823 }
824
825 return ERR_PTR(-EINVAL);
826 }
827
828 static struct nft_expr_type nft_ct_type __read_mostly = {
829 .name = "ct",
830 .select_ops = nft_ct_select_ops,
831 .policy = nft_ct_policy,
832 .maxattr = NFTA_CT_MAX,
833 .owner = THIS_MODULE,
834 };
835
nft_notrack_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)836 static void nft_notrack_eval(const struct nft_expr *expr,
837 struct nft_regs *regs,
838 const struct nft_pktinfo *pkt)
839 {
840 struct sk_buff *skb = pkt->skb;
841 enum ip_conntrack_info ctinfo;
842 struct nf_conn *ct;
843
844 ct = nf_ct_get(pkt->skb, &ctinfo);
845 /* Previously seen (loopback or untracked)? Ignore. */
846 if (ct || ctinfo == IP_CT_UNTRACKED)
847 return;
848
849 nf_ct_set(skb, ct, IP_CT_UNTRACKED);
850 }
851
852 static struct nft_expr_type nft_notrack_type;
853 static const struct nft_expr_ops nft_notrack_ops = {
854 .type = &nft_notrack_type,
855 .size = NFT_EXPR_SIZE(0),
856 .eval = nft_notrack_eval,
857 .reduce = NFT_REDUCE_READONLY,
858 };
859
860 static struct nft_expr_type nft_notrack_type __read_mostly = {
861 .name = "notrack",
862 .ops = &nft_notrack_ops,
863 .owner = THIS_MODULE,
864 };
865
866 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
867 static int
nft_ct_timeout_parse_policy(void * timeouts,const struct nf_conntrack_l4proto * l4proto,struct net * net,const struct nlattr * attr)868 nft_ct_timeout_parse_policy(void *timeouts,
869 const struct nf_conntrack_l4proto *l4proto,
870 struct net *net, const struct nlattr *attr)
871 {
872 struct nlattr **tb;
873 int ret = 0;
874
875 tb = kcalloc(l4proto->ctnl_timeout.nlattr_max + 1, sizeof(*tb),
876 GFP_KERNEL);
877
878 if (!tb)
879 return -ENOMEM;
880
881 ret = nla_parse_nested_deprecated(tb,
882 l4proto->ctnl_timeout.nlattr_max,
883 attr,
884 l4proto->ctnl_timeout.nla_policy,
885 NULL);
886 if (ret < 0)
887 goto err;
888
889 ret = l4proto->ctnl_timeout.nlattr_to_obj(tb, net, timeouts);
890
891 err:
892 kfree(tb);
893 return ret;
894 }
895
896 struct nft_ct_timeout_obj {
897 struct nf_ct_timeout *timeout;
898 u8 l4proto;
899 };
900
nft_ct_timeout_obj_eval(struct nft_object * obj,struct nft_regs * regs,const struct nft_pktinfo * pkt)901 static void nft_ct_timeout_obj_eval(struct nft_object *obj,
902 struct nft_regs *regs,
903 const struct nft_pktinfo *pkt)
904 {
905 const struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
906 struct nf_conn *ct = (struct nf_conn *)skb_nfct(pkt->skb);
907 struct nf_conn_timeout *timeout;
908 const unsigned int *values;
909
910 if (priv->l4proto != pkt->tprot)
911 return;
912
913 if (!ct || nf_ct_is_template(ct) || nf_ct_is_confirmed(ct))
914 return;
915
916 timeout = nf_ct_timeout_find(ct);
917 if (!timeout) {
918 timeout = nf_ct_timeout_ext_add(ct, priv->timeout, GFP_ATOMIC);
919 if (!timeout) {
920 regs->verdict.code = NF_DROP;
921 return;
922 }
923 }
924
925 rcu_assign_pointer(timeout->timeout, priv->timeout);
926
927 /* adjust the timeout as per 'new' state. ct is unconfirmed,
928 * so the current timestamp must not be added.
929 */
930 values = nf_ct_timeout_data(timeout);
931 if (values)
932 nf_ct_refresh(ct, pkt->skb, values[0]);
933 }
934
nft_ct_timeout_obj_init(const struct nft_ctx * ctx,const struct nlattr * const tb[],struct nft_object * obj)935 static int nft_ct_timeout_obj_init(const struct nft_ctx *ctx,
936 const struct nlattr * const tb[],
937 struct nft_object *obj)
938 {
939 struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
940 const struct nf_conntrack_l4proto *l4proto;
941 struct nf_ct_timeout *timeout;
942 int l3num = ctx->family;
943 __u8 l4num;
944 int ret;
945
946 if (!tb[NFTA_CT_TIMEOUT_L4PROTO] ||
947 !tb[NFTA_CT_TIMEOUT_DATA])
948 return -EINVAL;
949
950 if (tb[NFTA_CT_TIMEOUT_L3PROTO])
951 l3num = ntohs(nla_get_be16(tb[NFTA_CT_TIMEOUT_L3PROTO]));
952
953 l4num = nla_get_u8(tb[NFTA_CT_TIMEOUT_L4PROTO]);
954 priv->l4proto = l4num;
955
956 l4proto = nf_ct_l4proto_find(l4num);
957
958 if (l4proto->l4proto != l4num) {
959 ret = -EOPNOTSUPP;
960 goto err_proto_put;
961 }
962
963 timeout = kzalloc(sizeof(struct nf_ct_timeout) +
964 l4proto->ctnl_timeout.obj_size, GFP_KERNEL);
965 if (timeout == NULL) {
966 ret = -ENOMEM;
967 goto err_proto_put;
968 }
969
970 ret = nft_ct_timeout_parse_policy(&timeout->data, l4proto, ctx->net,
971 tb[NFTA_CT_TIMEOUT_DATA]);
972 if (ret < 0)
973 goto err_free_timeout;
974
975 timeout->l3num = l3num;
976 timeout->l4proto = l4proto;
977
978 ret = nf_ct_netns_get(ctx->net, ctx->family);
979 if (ret < 0)
980 goto err_free_timeout;
981
982 priv->timeout = timeout;
983 return 0;
984
985 err_free_timeout:
986 kfree(timeout);
987 err_proto_put:
988 return ret;
989 }
990
nft_ct_timeout_obj_destroy(const struct nft_ctx * ctx,struct nft_object * obj)991 static void nft_ct_timeout_obj_destroy(const struct nft_ctx *ctx,
992 struct nft_object *obj)
993 {
994 struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
995 struct nf_ct_timeout *timeout = priv->timeout;
996
997 nf_ct_untimeout(ctx->net, timeout);
998 nf_ct_netns_put(ctx->net, ctx->family);
999 kfree(priv->timeout);
1000 }
1001
nft_ct_timeout_obj_dump(struct sk_buff * skb,struct nft_object * obj,bool reset)1002 static int nft_ct_timeout_obj_dump(struct sk_buff *skb,
1003 struct nft_object *obj, bool reset)
1004 {
1005 const struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
1006 const struct nf_ct_timeout *timeout = priv->timeout;
1007 struct nlattr *nest_params;
1008 int ret;
1009
1010 if (nla_put_u8(skb, NFTA_CT_TIMEOUT_L4PROTO, timeout->l4proto->l4proto) ||
1011 nla_put_be16(skb, NFTA_CT_TIMEOUT_L3PROTO, htons(timeout->l3num)))
1012 return -1;
1013
1014 nest_params = nla_nest_start(skb, NFTA_CT_TIMEOUT_DATA);
1015 if (!nest_params)
1016 return -1;
1017
1018 ret = timeout->l4proto->ctnl_timeout.obj_to_nlattr(skb, &timeout->data);
1019 if (ret < 0)
1020 return -1;
1021 nla_nest_end(skb, nest_params);
1022 return 0;
1023 }
1024
1025 static const struct nla_policy nft_ct_timeout_policy[NFTA_CT_TIMEOUT_MAX + 1] = {
1026 [NFTA_CT_TIMEOUT_L3PROTO] = {.type = NLA_U16 },
1027 [NFTA_CT_TIMEOUT_L4PROTO] = {.type = NLA_U8 },
1028 [NFTA_CT_TIMEOUT_DATA] = {.type = NLA_NESTED },
1029 };
1030
1031 static struct nft_object_type nft_ct_timeout_obj_type;
1032
1033 static const struct nft_object_ops nft_ct_timeout_obj_ops = {
1034 .type = &nft_ct_timeout_obj_type,
1035 .size = sizeof(struct nft_ct_timeout_obj),
1036 .eval = nft_ct_timeout_obj_eval,
1037 .init = nft_ct_timeout_obj_init,
1038 .destroy = nft_ct_timeout_obj_destroy,
1039 .dump = nft_ct_timeout_obj_dump,
1040 };
1041
1042 static struct nft_object_type nft_ct_timeout_obj_type __read_mostly = {
1043 .type = NFT_OBJECT_CT_TIMEOUT,
1044 .ops = &nft_ct_timeout_obj_ops,
1045 .maxattr = NFTA_CT_TIMEOUT_MAX,
1046 .policy = nft_ct_timeout_policy,
1047 .owner = THIS_MODULE,
1048 };
1049 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
1050
nft_ct_helper_obj_init(const struct nft_ctx * ctx,const struct nlattr * const tb[],struct nft_object * obj)1051 static int nft_ct_helper_obj_init(const struct nft_ctx *ctx,
1052 const struct nlattr * const tb[],
1053 struct nft_object *obj)
1054 {
1055 struct nft_ct_helper_obj *priv = nft_obj_data(obj);
1056 struct nf_conntrack_helper *help4, *help6;
1057 char name[NF_CT_HELPER_NAME_LEN];
1058 int family = ctx->family;
1059 int err;
1060
1061 if (!tb[NFTA_CT_HELPER_NAME] || !tb[NFTA_CT_HELPER_L4PROTO])
1062 return -EINVAL;
1063
1064 priv->l4proto = nla_get_u8(tb[NFTA_CT_HELPER_L4PROTO]);
1065 if (!priv->l4proto)
1066 return -ENOENT;
1067
1068 nla_strscpy(name, tb[NFTA_CT_HELPER_NAME], sizeof(name));
1069
1070 if (tb[NFTA_CT_HELPER_L3PROTO])
1071 family = ntohs(nla_get_be16(tb[NFTA_CT_HELPER_L3PROTO]));
1072
1073 help4 = NULL;
1074 help6 = NULL;
1075
1076 switch (family) {
1077 case NFPROTO_IPV4:
1078 if (ctx->family == NFPROTO_IPV6)
1079 return -EINVAL;
1080
1081 help4 = nf_conntrack_helper_try_module_get(name, family,
1082 priv->l4proto);
1083 break;
1084 case NFPROTO_IPV6:
1085 if (ctx->family == NFPROTO_IPV4)
1086 return -EINVAL;
1087
1088 help6 = nf_conntrack_helper_try_module_get(name, family,
1089 priv->l4proto);
1090 break;
1091 case NFPROTO_NETDEV:
1092 case NFPROTO_BRIDGE:
1093 case NFPROTO_INET:
1094 help4 = nf_conntrack_helper_try_module_get(name, NFPROTO_IPV4,
1095 priv->l4proto);
1096 help6 = nf_conntrack_helper_try_module_get(name, NFPROTO_IPV6,
1097 priv->l4proto);
1098 break;
1099 default:
1100 return -EAFNOSUPPORT;
1101 }
1102
1103 /* && is intentional; only error if INET found neither ipv4 or ipv6 */
1104 if (!help4 && !help6)
1105 return -ENOENT;
1106
1107 priv->helper4 = help4;
1108 priv->helper6 = help6;
1109
1110 err = nf_ct_netns_get(ctx->net, ctx->family);
1111 if (err < 0)
1112 goto err_put_helper;
1113
1114 return 0;
1115
1116 err_put_helper:
1117 if (priv->helper4)
1118 nf_conntrack_helper_put(priv->helper4);
1119 if (priv->helper6)
1120 nf_conntrack_helper_put(priv->helper6);
1121 return err;
1122 }
1123
nft_ct_helper_obj_destroy(const struct nft_ctx * ctx,struct nft_object * obj)1124 static void nft_ct_helper_obj_destroy(const struct nft_ctx *ctx,
1125 struct nft_object *obj)
1126 {
1127 struct nft_ct_helper_obj *priv = nft_obj_data(obj);
1128
1129 if (priv->helper4)
1130 nf_conntrack_helper_put(priv->helper4);
1131 if (priv->helper6)
1132 nf_conntrack_helper_put(priv->helper6);
1133
1134 nf_ct_netns_put(ctx->net, ctx->family);
1135 }
1136
nft_ct_helper_obj_eval(struct nft_object * obj,struct nft_regs * regs,const struct nft_pktinfo * pkt)1137 static void nft_ct_helper_obj_eval(struct nft_object *obj,
1138 struct nft_regs *regs,
1139 const struct nft_pktinfo *pkt)
1140 {
1141 const struct nft_ct_helper_obj *priv = nft_obj_data(obj);
1142 struct nf_conn *ct = (struct nf_conn *)skb_nfct(pkt->skb);
1143 struct nf_conntrack_helper *to_assign = NULL;
1144 struct nf_conn_help *help;
1145
1146 if (!ct ||
1147 nf_ct_is_confirmed(ct) ||
1148 nf_ct_is_template(ct) ||
1149 priv->l4proto != nf_ct_protonum(ct))
1150 return;
1151
1152 switch (nf_ct_l3num(ct)) {
1153 case NFPROTO_IPV4:
1154 to_assign = priv->helper4;
1155 break;
1156 case NFPROTO_IPV6:
1157 to_assign = priv->helper6;
1158 break;
1159 default:
1160 WARN_ON_ONCE(1);
1161 return;
1162 }
1163
1164 if (!to_assign)
1165 return;
1166
1167 if (test_bit(IPS_HELPER_BIT, &ct->status))
1168 return;
1169
1170 help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
1171 if (help) {
1172 rcu_assign_pointer(help->helper, to_assign);
1173 set_bit(IPS_HELPER_BIT, &ct->status);
1174 }
1175 }
1176
nft_ct_helper_obj_dump(struct sk_buff * skb,struct nft_object * obj,bool reset)1177 static int nft_ct_helper_obj_dump(struct sk_buff *skb,
1178 struct nft_object *obj, bool reset)
1179 {
1180 const struct nft_ct_helper_obj *priv = nft_obj_data(obj);
1181 const struct nf_conntrack_helper *helper;
1182 u16 family;
1183
1184 if (priv->helper4 && priv->helper6) {
1185 family = NFPROTO_INET;
1186 helper = priv->helper4;
1187 } else if (priv->helper6) {
1188 family = NFPROTO_IPV6;
1189 helper = priv->helper6;
1190 } else {
1191 family = NFPROTO_IPV4;
1192 helper = priv->helper4;
1193 }
1194
1195 if (nla_put_string(skb, NFTA_CT_HELPER_NAME, helper->name))
1196 return -1;
1197
1198 if (nla_put_u8(skb, NFTA_CT_HELPER_L4PROTO, priv->l4proto))
1199 return -1;
1200
1201 if (nla_put_be16(skb, NFTA_CT_HELPER_L3PROTO, htons(family)))
1202 return -1;
1203
1204 return 0;
1205 }
1206
1207 static const struct nla_policy nft_ct_helper_policy[NFTA_CT_HELPER_MAX + 1] = {
1208 [NFTA_CT_HELPER_NAME] = { .type = NLA_STRING,
1209 .len = NF_CT_HELPER_NAME_LEN - 1 },
1210 [NFTA_CT_HELPER_L3PROTO] = { .type = NLA_U16 },
1211 [NFTA_CT_HELPER_L4PROTO] = { .type = NLA_U8 },
1212 };
1213
1214 static struct nft_object_type nft_ct_helper_obj_type;
1215 static const struct nft_object_ops nft_ct_helper_obj_ops = {
1216 .type = &nft_ct_helper_obj_type,
1217 .size = sizeof(struct nft_ct_helper_obj),
1218 .eval = nft_ct_helper_obj_eval,
1219 .init = nft_ct_helper_obj_init,
1220 .destroy = nft_ct_helper_obj_destroy,
1221 .dump = nft_ct_helper_obj_dump,
1222 };
1223
1224 static struct nft_object_type nft_ct_helper_obj_type __read_mostly = {
1225 .type = NFT_OBJECT_CT_HELPER,
1226 .ops = &nft_ct_helper_obj_ops,
1227 .maxattr = NFTA_CT_HELPER_MAX,
1228 .policy = nft_ct_helper_policy,
1229 .owner = THIS_MODULE,
1230 };
1231
1232 struct nft_ct_expect_obj {
1233 u16 l3num;
1234 __be16 dport;
1235 u8 l4proto;
1236 u8 size;
1237 u32 timeout;
1238 };
1239
nft_ct_expect_obj_init(const struct nft_ctx * ctx,const struct nlattr * const tb[],struct nft_object * obj)1240 static int nft_ct_expect_obj_init(const struct nft_ctx *ctx,
1241 const struct nlattr * const tb[],
1242 struct nft_object *obj)
1243 {
1244 struct nft_ct_expect_obj *priv = nft_obj_data(obj);
1245
1246 if (!tb[NFTA_CT_EXPECT_L4PROTO] ||
1247 !tb[NFTA_CT_EXPECT_DPORT] ||
1248 !tb[NFTA_CT_EXPECT_TIMEOUT] ||
1249 !tb[NFTA_CT_EXPECT_SIZE])
1250 return -EINVAL;
1251
1252 priv->l3num = ctx->family;
1253 if (tb[NFTA_CT_EXPECT_L3PROTO])
1254 priv->l3num = ntohs(nla_get_be16(tb[NFTA_CT_EXPECT_L3PROTO]));
1255
1256 switch (priv->l3num) {
1257 case NFPROTO_IPV4:
1258 case NFPROTO_IPV6:
1259 if (priv->l3num == ctx->family || ctx->family == NFPROTO_INET)
1260 break;
1261
1262 return -EINVAL;
1263 case NFPROTO_INET: /* tuple.src.l3num supports NFPROTO_IPV4/6 only */
1264 default:
1265 return -EAFNOSUPPORT;
1266 }
1267
1268 priv->l4proto = nla_get_u8(tb[NFTA_CT_EXPECT_L4PROTO]);
1269 switch (priv->l4proto) {
1270 case IPPROTO_TCP:
1271 case IPPROTO_UDP:
1272 case IPPROTO_UDPLITE:
1273 case IPPROTO_DCCP:
1274 case IPPROTO_SCTP:
1275 break;
1276 default:
1277 return -EOPNOTSUPP;
1278 }
1279
1280 priv->dport = nla_get_be16(tb[NFTA_CT_EXPECT_DPORT]);
1281 priv->timeout = nla_get_u32(tb[NFTA_CT_EXPECT_TIMEOUT]);
1282 priv->size = nla_get_u8(tb[NFTA_CT_EXPECT_SIZE]);
1283
1284 return nf_ct_netns_get(ctx->net, ctx->family);
1285 }
1286
nft_ct_expect_obj_destroy(const struct nft_ctx * ctx,struct nft_object * obj)1287 static void nft_ct_expect_obj_destroy(const struct nft_ctx *ctx,
1288 struct nft_object *obj)
1289 {
1290 nf_ct_netns_put(ctx->net, ctx->family);
1291 }
1292
nft_ct_expect_obj_dump(struct sk_buff * skb,struct nft_object * obj,bool reset)1293 static int nft_ct_expect_obj_dump(struct sk_buff *skb,
1294 struct nft_object *obj, bool reset)
1295 {
1296 const struct nft_ct_expect_obj *priv = nft_obj_data(obj);
1297
1298 if (nla_put_be16(skb, NFTA_CT_EXPECT_L3PROTO, htons(priv->l3num)) ||
1299 nla_put_u8(skb, NFTA_CT_EXPECT_L4PROTO, priv->l4proto) ||
1300 nla_put_be16(skb, NFTA_CT_EXPECT_DPORT, priv->dport) ||
1301 nla_put_u32(skb, NFTA_CT_EXPECT_TIMEOUT, priv->timeout) ||
1302 nla_put_u8(skb, NFTA_CT_EXPECT_SIZE, priv->size))
1303 return -1;
1304
1305 return 0;
1306 }
1307
nft_ct_expect_obj_eval(struct nft_object * obj,struct nft_regs * regs,const struct nft_pktinfo * pkt)1308 static void nft_ct_expect_obj_eval(struct nft_object *obj,
1309 struct nft_regs *regs,
1310 const struct nft_pktinfo *pkt)
1311 {
1312 const struct nft_ct_expect_obj *priv = nft_obj_data(obj);
1313 struct nf_conntrack_expect *exp;
1314 enum ip_conntrack_info ctinfo;
1315 struct nf_conn_help *help;
1316 enum ip_conntrack_dir dir;
1317 u16 l3num = priv->l3num;
1318 struct nf_conn *ct;
1319
1320 ct = nf_ct_get(pkt->skb, &ctinfo);
1321 if (!ct || nf_ct_is_confirmed(ct) || nf_ct_is_template(ct)) {
1322 regs->verdict.code = NFT_BREAK;
1323 return;
1324 }
1325 dir = CTINFO2DIR(ctinfo);
1326
1327 help = nfct_help(ct);
1328 if (!help)
1329 help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
1330 if (!help) {
1331 regs->verdict.code = NF_DROP;
1332 return;
1333 }
1334
1335 if (help->expecting[NF_CT_EXPECT_CLASS_DEFAULT] >= priv->size) {
1336 regs->verdict.code = NFT_BREAK;
1337 return;
1338 }
1339 if (l3num == NFPROTO_INET)
1340 l3num = nf_ct_l3num(ct);
1341
1342 exp = nf_ct_expect_alloc(ct);
1343 if (exp == NULL) {
1344 regs->verdict.code = NF_DROP;
1345 return;
1346 }
1347 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, l3num,
1348 &ct->tuplehash[!dir].tuple.src.u3,
1349 &ct->tuplehash[!dir].tuple.dst.u3,
1350 priv->l4proto, NULL, &priv->dport);
1351 exp->timeout.expires = jiffies + priv->timeout * HZ;
1352
1353 if (nf_ct_expect_related(exp, 0) != 0)
1354 regs->verdict.code = NF_DROP;
1355 }
1356
1357 static const struct nla_policy nft_ct_expect_policy[NFTA_CT_EXPECT_MAX + 1] = {
1358 [NFTA_CT_EXPECT_L3PROTO] = { .type = NLA_U16 },
1359 [NFTA_CT_EXPECT_L4PROTO] = { .type = NLA_U8 },
1360 [NFTA_CT_EXPECT_DPORT] = { .type = NLA_U16 },
1361 [NFTA_CT_EXPECT_TIMEOUT] = { .type = NLA_U32 },
1362 [NFTA_CT_EXPECT_SIZE] = { .type = NLA_U8 },
1363 };
1364
1365 static struct nft_object_type nft_ct_expect_obj_type;
1366
1367 static const struct nft_object_ops nft_ct_expect_obj_ops = {
1368 .type = &nft_ct_expect_obj_type,
1369 .size = sizeof(struct nft_ct_expect_obj),
1370 .eval = nft_ct_expect_obj_eval,
1371 .init = nft_ct_expect_obj_init,
1372 .destroy = nft_ct_expect_obj_destroy,
1373 .dump = nft_ct_expect_obj_dump,
1374 };
1375
1376 static struct nft_object_type nft_ct_expect_obj_type __read_mostly = {
1377 .type = NFT_OBJECT_CT_EXPECT,
1378 .ops = &nft_ct_expect_obj_ops,
1379 .maxattr = NFTA_CT_EXPECT_MAX,
1380 .policy = nft_ct_expect_policy,
1381 .owner = THIS_MODULE,
1382 };
1383
nft_ct_module_init(void)1384 static int __init nft_ct_module_init(void)
1385 {
1386 int err;
1387
1388 BUILD_BUG_ON(NF_CT_LABELS_MAX_SIZE > NFT_REG_SIZE);
1389
1390 err = nft_register_expr(&nft_ct_type);
1391 if (err < 0)
1392 return err;
1393
1394 err = nft_register_expr(&nft_notrack_type);
1395 if (err < 0)
1396 goto err1;
1397
1398 err = nft_register_obj(&nft_ct_helper_obj_type);
1399 if (err < 0)
1400 goto err2;
1401
1402 err = nft_register_obj(&nft_ct_expect_obj_type);
1403 if (err < 0)
1404 goto err3;
1405 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1406 err = nft_register_obj(&nft_ct_timeout_obj_type);
1407 if (err < 0)
1408 goto err4;
1409 #endif
1410 return 0;
1411
1412 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1413 err4:
1414 nft_unregister_obj(&nft_ct_expect_obj_type);
1415 #endif
1416 err3:
1417 nft_unregister_obj(&nft_ct_helper_obj_type);
1418 err2:
1419 nft_unregister_expr(&nft_notrack_type);
1420 err1:
1421 nft_unregister_expr(&nft_ct_type);
1422 return err;
1423 }
1424
nft_ct_module_exit(void)1425 static void __exit nft_ct_module_exit(void)
1426 {
1427 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1428 nft_unregister_obj(&nft_ct_timeout_obj_type);
1429 #endif
1430 nft_unregister_obj(&nft_ct_expect_obj_type);
1431 nft_unregister_obj(&nft_ct_helper_obj_type);
1432 nft_unregister_expr(&nft_notrack_type);
1433 nft_unregister_expr(&nft_ct_type);
1434 }
1435
1436 module_init(nft_ct_module_init);
1437 module_exit(nft_ct_module_exit);
1438
1439 MODULE_LICENSE("GPL");
1440 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
1441 MODULE_ALIAS_NFT_EXPR("ct");
1442 MODULE_ALIAS_NFT_EXPR("notrack");
1443 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_HELPER);
1444 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_TIMEOUT);
1445 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_EXPECT);
1446 MODULE_DESCRIPTION("Netfilter nf_tables conntrack module");
1447