xref: /linux/net/sched/act_ct.c (revision 056a5087d87ead77dedbe9cf5bde53b7cd4b4651)
1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 /* -
3  * net/sched/act_ct.c  Connection Tracking action
4  *
5  * Authors:   Paul Blakey <paulb@mellanox.com>
6  *            Yossi Kuperman <yossiku@mellanox.com>
7  *            Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/skbuff.h>
14 #include <linux/rtnetlink.h>
15 #include <linux/pkt_cls.h>
16 #include <linux/if_tunnel.h>
17 #include <linux/ip.h>
18 #include <linux/ipv6.h>
19 #include <linux/rhashtable.h>
20 #include <net/gre.h>
21 #include <net/netlink.h>
22 #include <net/pkt_sched.h>
23 #include <net/pkt_cls.h>
24 #include <net/act_api.h>
25 #include <net/ip.h>
26 #include <net/ipv6_frag.h>
27 #include <uapi/linux/tc_act/tc_ct.h>
28 #include <net/tc_act/tc_ct.h>
29 #include <net/tc_wrapper.h>
30 
31 #include <net/netfilter/nf_flow_table.h>
32 #include <net/netfilter/nf_conntrack.h>
33 #include <net/netfilter/nf_conntrack_core.h>
34 #include <net/netfilter/nf_conntrack_zones.h>
35 #include <net/netfilter/nf_conntrack_helper.h>
36 #include <net/netfilter/nf_conntrack_acct.h>
37 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
38 #include <net/netfilter/nf_conntrack_act_ct.h>
39 #include <net/netfilter/nf_conntrack_seqadj.h>
40 #include <uapi/linux/netfilter/nf_nat.h>
41 
42 static struct workqueue_struct *act_ct_wq;
43 static struct rhashtable zones_ht;
44 static DEFINE_MUTEX(zones_mutex);
45 
46 struct zones_ht_key {
47 	struct net *net;
48 	u16 zone;
49 };
50 
51 struct tcf_ct_flow_table {
52 	struct rhash_head node; /* In zones tables */
53 
54 	struct rcu_work rwork;
55 	struct nf_flowtable nf_ft;
56 	refcount_t ref;
57 	struct zones_ht_key key;
58 
59 	bool dying;
60 };
61 
62 static const struct rhashtable_params zones_params = {
63 	.head_offset = offsetof(struct tcf_ct_flow_table, node),
64 	.key_offset = offsetof(struct tcf_ct_flow_table, key),
65 	.key_len = offsetofend(struct zones_ht_key, zone),
66 	.automatic_shrinking = true,
67 };
68 
69 static struct flow_action_entry *
70 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action)
71 {
72 	int i = flow_action->num_entries++;
73 
74 	return &flow_action->entries[i];
75 }
76 
77 static void tcf_ct_add_mangle_action(struct flow_action *action,
78 				     enum flow_action_mangle_base htype,
79 				     u32 offset,
80 				     u32 mask,
81 				     u32 val)
82 {
83 	struct flow_action_entry *entry;
84 
85 	entry = tcf_ct_flow_table_flow_action_get_next(action);
86 	entry->id = FLOW_ACTION_MANGLE;
87 	entry->mangle.htype = htype;
88 	entry->mangle.mask = ~mask;
89 	entry->mangle.offset = offset;
90 	entry->mangle.val = val;
91 }
92 
93 /* The following nat helper functions check if the inverted reverse tuple
94  * (target) is different then the current dir tuple - meaning nat for ports
95  * and/or ip is needed, and add the relevant mangle actions.
96  */
97 static void
98 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple,
99 				      struct nf_conntrack_tuple target,
100 				      struct flow_action *action)
101 {
102 	if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
103 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
104 					 offsetof(struct iphdr, saddr),
105 					 0xFFFFFFFF,
106 					 be32_to_cpu(target.src.u3.ip));
107 	if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
108 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
109 					 offsetof(struct iphdr, daddr),
110 					 0xFFFFFFFF,
111 					 be32_to_cpu(target.dst.u3.ip));
112 }
113 
114 static void
115 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action,
116 				   union nf_inet_addr *addr,
117 				   u32 offset)
118 {
119 	int i;
120 
121 	for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++)
122 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
123 					 i * sizeof(u32) + offset,
124 					 0xFFFFFFFF, be32_to_cpu(addr->ip6[i]));
125 }
126 
127 static void
128 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple,
129 				      struct nf_conntrack_tuple target,
130 				      struct flow_action *action)
131 {
132 	if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
133 		tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3,
134 						   offsetof(struct ipv6hdr,
135 							    saddr));
136 	if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
137 		tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3,
138 						   offsetof(struct ipv6hdr,
139 							    daddr));
140 }
141 
142 static void
143 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple,
144 				     struct nf_conntrack_tuple target,
145 				     struct flow_action *action)
146 {
147 	__be16 target_src = target.src.u.tcp.port;
148 	__be16 target_dst = target.dst.u.tcp.port;
149 
150 	if (target_src != tuple->src.u.tcp.port)
151 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
152 					 offsetof(struct tcphdr, source),
153 					 0xFFFF, be16_to_cpu(target_src));
154 	if (target_dst != tuple->dst.u.tcp.port)
155 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
156 					 offsetof(struct tcphdr, dest),
157 					 0xFFFF, be16_to_cpu(target_dst));
158 }
159 
160 static void
161 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple,
162 				     struct nf_conntrack_tuple target,
163 				     struct flow_action *action)
164 {
165 	__be16 target_src = target.src.u.udp.port;
166 	__be16 target_dst = target.dst.u.udp.port;
167 
168 	if (target_src != tuple->src.u.udp.port)
169 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
170 					 offsetof(struct udphdr, source),
171 					 0xFFFF, be16_to_cpu(target_src));
172 	if (target_dst != tuple->dst.u.udp.port)
173 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
174 					 offsetof(struct udphdr, dest),
175 					 0xFFFF, be16_to_cpu(target_dst));
176 }
177 
178 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct,
179 					      enum ip_conntrack_dir dir,
180 					      enum ip_conntrack_info ctinfo,
181 					      struct flow_action *action)
182 {
183 	struct nf_conn_labels *ct_labels;
184 	struct flow_action_entry *entry;
185 	u32 *act_ct_labels;
186 
187 	entry = tcf_ct_flow_table_flow_action_get_next(action);
188 	entry->id = FLOW_ACTION_CT_METADATA;
189 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
190 	entry->ct_metadata.mark = READ_ONCE(ct->mark);
191 #endif
192 	/* aligns with the CT reference on the SKB nf_ct_set */
193 	entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
194 	entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL;
195 
196 	act_ct_labels = entry->ct_metadata.labels;
197 	ct_labels = nf_ct_labels_find(ct);
198 	if (ct_labels)
199 		memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
200 	else
201 		memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
202 }
203 
204 static int tcf_ct_flow_table_add_action_nat(struct net *net,
205 					    struct nf_conn *ct,
206 					    enum ip_conntrack_dir dir,
207 					    struct flow_action *action)
208 {
209 	const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
210 	struct nf_conntrack_tuple target;
211 
212 	if (!(ct->status & IPS_NAT_MASK))
213 		return 0;
214 
215 	nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
216 
217 	switch (tuple->src.l3num) {
218 	case NFPROTO_IPV4:
219 		tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
220 						      action);
221 		break;
222 	case NFPROTO_IPV6:
223 		tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
224 						      action);
225 		break;
226 	default:
227 		return -EOPNOTSUPP;
228 	}
229 
230 	switch (nf_ct_protonum(ct)) {
231 	case IPPROTO_TCP:
232 		tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
233 		break;
234 	case IPPROTO_UDP:
235 		tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
236 		break;
237 	default:
238 		return -EOPNOTSUPP;
239 	}
240 
241 	return 0;
242 }
243 
244 static int tcf_ct_flow_table_fill_actions(struct net *net,
245 					  struct flow_offload *flow,
246 					  enum flow_offload_tuple_dir tdir,
247 					  struct nf_flow_rule *flow_rule)
248 {
249 	struct flow_action *action = &flow_rule->rule->action;
250 	int num_entries = action->num_entries;
251 	struct nf_conn *ct = flow->ct;
252 	enum ip_conntrack_info ctinfo;
253 	enum ip_conntrack_dir dir;
254 	int i, err;
255 
256 	switch (tdir) {
257 	case FLOW_OFFLOAD_DIR_ORIGINAL:
258 		dir = IP_CT_DIR_ORIGINAL;
259 		ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ?
260 			IP_CT_ESTABLISHED : IP_CT_NEW;
261 		if (ctinfo == IP_CT_ESTABLISHED)
262 			set_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags);
263 		break;
264 	case FLOW_OFFLOAD_DIR_REPLY:
265 		dir = IP_CT_DIR_REPLY;
266 		ctinfo = IP_CT_ESTABLISHED_REPLY;
267 		break;
268 	default:
269 		return -EOPNOTSUPP;
270 	}
271 
272 	err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
273 	if (err)
274 		goto err_nat;
275 
276 	tcf_ct_flow_table_add_action_meta(ct, dir, ctinfo, action);
277 	return 0;
278 
279 err_nat:
280 	/* Clear filled actions */
281 	for (i = num_entries; i < action->num_entries; i++)
282 		memset(&action->entries[i], 0, sizeof(action->entries[i]));
283 	action->num_entries = num_entries;
284 
285 	return err;
286 }
287 
288 static bool tcf_ct_flow_is_outdated(const struct flow_offload *flow)
289 {
290 	return test_bit(IPS_SEEN_REPLY_BIT, &flow->ct->status) &&
291 	       test_bit(IPS_HW_OFFLOAD_BIT, &flow->ct->status) &&
292 	       !test_bit(NF_FLOW_HW_PENDING, &flow->flags) &&
293 	       !test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags);
294 }
295 
296 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft);
297 
298 static void tcf_ct_nf_get(struct nf_flowtable *ft)
299 {
300 	struct tcf_ct_flow_table *ct_ft =
301 		container_of(ft, struct tcf_ct_flow_table, nf_ft);
302 
303 	tcf_ct_flow_table_get_ref(ct_ft);
304 }
305 
306 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft);
307 
308 static void tcf_ct_nf_put(struct nf_flowtable *ft)
309 {
310 	struct tcf_ct_flow_table *ct_ft =
311 		container_of(ft, struct tcf_ct_flow_table, nf_ft);
312 
313 	tcf_ct_flow_table_put(ct_ft);
314 }
315 
316 static struct nf_flowtable_type flowtable_ct = {
317 	.gc		= tcf_ct_flow_is_outdated,
318 	.action		= tcf_ct_flow_table_fill_actions,
319 	.get		= tcf_ct_nf_get,
320 	.put		= tcf_ct_nf_put,
321 	.owner		= THIS_MODULE,
322 };
323 
324 static int tcf_ct_flow_table_get(struct net *net, struct tcf_ct_params *params)
325 {
326 	struct zones_ht_key key = { .net = net, .zone = params->zone };
327 	struct tcf_ct_flow_table *ct_ft;
328 	int err = -ENOMEM;
329 
330 	mutex_lock(&zones_mutex);
331 	rcu_read_lock();
332 	ct_ft = rhashtable_lookup(&zones_ht, &key, zones_params);
333 	if (ct_ft && refcount_inc_not_zero(&ct_ft->ref)) {
334 		rcu_read_unlock();
335 		goto out_unlock;
336 	}
337 	rcu_read_unlock();
338 
339 	ct_ft = kzalloc_obj(*ct_ft);
340 	if (!ct_ft)
341 		goto err_alloc;
342 	refcount_set(&ct_ft->ref, 1);
343 
344 	ct_ft->key = key;
345 	err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
346 	if (err)
347 		goto err_insert;
348 
349 	ct_ft->nf_ft.type = &flowtable_ct;
350 	ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD |
351 			      NF_FLOWTABLE_COUNTER;
352 	err = nf_flow_table_init(&ct_ft->nf_ft);
353 	if (err)
354 		goto err_init;
355 	write_pnet(&ct_ft->nf_ft.net, net);
356 
357 	__module_get(THIS_MODULE);
358 out_unlock:
359 	params->ct_ft = ct_ft;
360 	params->nf_ft = &ct_ft->nf_ft;
361 	mutex_unlock(&zones_mutex);
362 
363 	return 0;
364 
365 err_init:
366 	rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
367 err_insert:
368 	kfree(ct_ft);
369 err_alloc:
370 	mutex_unlock(&zones_mutex);
371 	return err;
372 }
373 
374 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft)
375 {
376 	refcount_inc(&ct_ft->ref);
377 }
378 
379 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
380 {
381 	struct tcf_ct_flow_table *ct_ft;
382 	struct flow_block *block;
383 
384 	ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
385 			     rwork);
386 	nf_flow_table_free(&ct_ft->nf_ft);
387 
388 	block = &ct_ft->nf_ft.flow_block;
389 	down_write(&ct_ft->nf_ft.flow_block_lock);
390 	WARN_ON(!list_empty(&block->cb_list));
391 	up_write(&ct_ft->nf_ft.flow_block_lock);
392 	kfree(ct_ft);
393 
394 	module_put(THIS_MODULE);
395 }
396 
397 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft)
398 {
399 	if (refcount_dec_and_test(&ct_ft->ref)) {
400 		rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
401 		INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
402 		queue_rcu_work(act_ct_wq, &ct_ft->rwork);
403 	}
404 }
405 
406 static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry,
407 				 struct nf_conn_act_ct_ext *act_ct_ext, u8 dir)
408 {
409 	entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC;
410 	entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir];
411 }
412 
413 static void tcf_ct_flow_ct_ext_ifidx_update(struct flow_offload *entry)
414 {
415 	struct nf_conn_act_ct_ext *act_ct_ext;
416 
417 	act_ct_ext = nf_conn_act_ct_ext_find(entry->ct);
418 	if (act_ct_ext) {
419 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
420 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
421 	}
422 }
423 
424 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
425 				  struct nf_conn *ct,
426 				  bool tcp, bool bidirectional)
427 {
428 	struct nf_conn_act_ct_ext *act_ct_ext;
429 	struct flow_offload *entry;
430 	int err;
431 
432 	if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
433 		return;
434 
435 	entry = flow_offload_alloc(ct);
436 	if (!entry) {
437 		WARN_ON_ONCE(1);
438 		goto err_alloc;
439 	}
440 
441 	if (tcp) {
442 		ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
443 		ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
444 	}
445 	if (bidirectional)
446 		__set_bit(NF_FLOW_HW_BIDIRECTIONAL, &entry->flags);
447 
448 	act_ct_ext = nf_conn_act_ct_ext_find(ct);
449 	if (act_ct_ext) {
450 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
451 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
452 	}
453 
454 	err = flow_offload_add(&ct_ft->nf_ft, entry);
455 	if (err)
456 		goto err_add;
457 
458 	return;
459 
460 err_add:
461 	flow_offload_free(entry);
462 err_alloc:
463 	clear_bit(IPS_OFFLOAD_BIT, &ct->status);
464 }
465 
466 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
467 					   struct nf_conn *ct,
468 					   enum ip_conntrack_info ctinfo)
469 {
470 	bool tcp = false, bidirectional = true;
471 
472 	switch (nf_ct_protonum(ct)) {
473 	case IPPROTO_TCP:
474 		if ((ctinfo != IP_CT_ESTABLISHED &&
475 		     ctinfo != IP_CT_ESTABLISHED_REPLY) ||
476 		    !test_bit(IPS_ASSURED_BIT, &ct->status) ||
477 		    ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
478 			return;
479 
480 		tcp = true;
481 		break;
482 	case IPPROTO_UDP:
483 		if (!nf_ct_is_confirmed(ct))
484 			return;
485 		if (!test_bit(IPS_ASSURED_BIT, &ct->status))
486 			bidirectional = false;
487 		break;
488 #ifdef CONFIG_NF_CT_PROTO_GRE
489 	case IPPROTO_GRE: {
490 		struct nf_conntrack_tuple *tuple;
491 
492 		if ((ctinfo != IP_CT_ESTABLISHED &&
493 		     ctinfo != IP_CT_ESTABLISHED_REPLY) ||
494 		    !test_bit(IPS_ASSURED_BIT, &ct->status) ||
495 		    ct->status & IPS_NAT_MASK)
496 			return;
497 
498 		tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
499 		/* No support for GRE v1 */
500 		if (tuple->src.u.gre.key || tuple->dst.u.gre.key)
501 			return;
502 		break;
503 	}
504 #endif
505 	default:
506 		return;
507 	}
508 
509 	if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
510 	    ct->status & IPS_SEQ_ADJUST)
511 		return;
512 
513 	tcf_ct_flow_table_add(ct_ft, ct, tcp, bidirectional);
514 }
515 
516 static bool
517 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
518 				  struct flow_offload_tuple *tuple,
519 				  struct tcphdr **tcph)
520 {
521 	struct flow_ports *ports;
522 	unsigned int thoff;
523 	struct iphdr *iph;
524 	size_t hdrsize;
525 	u8 ipproto;
526 
527 	if (!pskb_network_may_pull(skb, sizeof(*iph)))
528 		return false;
529 
530 	iph = ip_hdr(skb);
531 	thoff = iph->ihl * 4;
532 
533 	if (ip_is_fragment(iph) ||
534 	    unlikely(thoff != sizeof(struct iphdr)))
535 		return false;
536 
537 	ipproto = iph->protocol;
538 	switch (ipproto) {
539 	case IPPROTO_TCP:
540 		hdrsize = sizeof(struct tcphdr);
541 		break;
542 	case IPPROTO_UDP:
543 		hdrsize = sizeof(*ports);
544 		break;
545 #ifdef CONFIG_NF_CT_PROTO_GRE
546 	case IPPROTO_GRE:
547 		hdrsize = sizeof(struct gre_base_hdr);
548 		break;
549 #endif
550 	default:
551 		return false;
552 	}
553 
554 	if (iph->ttl <= 1)
555 		return false;
556 
557 	if (!pskb_network_may_pull(skb, thoff + hdrsize))
558 		return false;
559 
560 	switch (ipproto) {
561 	case IPPROTO_TCP:
562 		*tcph = (void *)(skb_network_header(skb) + thoff);
563 		fallthrough;
564 	case IPPROTO_UDP:
565 		ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
566 		tuple->src_port = ports->source;
567 		tuple->dst_port = ports->dest;
568 		break;
569 	case IPPROTO_GRE: {
570 		struct gre_base_hdr *greh;
571 
572 		greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
573 		if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
574 			return false;
575 		break;
576 	}
577 	}
578 
579 	iph = ip_hdr(skb);
580 
581 	tuple->src_v4.s_addr = iph->saddr;
582 	tuple->dst_v4.s_addr = iph->daddr;
583 	tuple->l3proto = AF_INET;
584 	tuple->l4proto = ipproto;
585 
586 	return true;
587 }
588 
589 static bool
590 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
591 				  struct flow_offload_tuple *tuple,
592 				  struct tcphdr **tcph)
593 {
594 	struct flow_ports *ports;
595 	struct ipv6hdr *ip6h;
596 	unsigned int thoff;
597 	size_t hdrsize;
598 	u8 nexthdr;
599 
600 	if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
601 		return false;
602 
603 	ip6h = ipv6_hdr(skb);
604 	thoff = sizeof(*ip6h);
605 
606 	nexthdr = ip6h->nexthdr;
607 	switch (nexthdr) {
608 	case IPPROTO_TCP:
609 		hdrsize = sizeof(struct tcphdr);
610 		break;
611 	case IPPROTO_UDP:
612 		hdrsize = sizeof(*ports);
613 		break;
614 #ifdef CONFIG_NF_CT_PROTO_GRE
615 	case IPPROTO_GRE:
616 		hdrsize = sizeof(struct gre_base_hdr);
617 		break;
618 #endif
619 	default:
620 		return false;
621 	}
622 
623 	if (ip6h->hop_limit <= 1)
624 		return false;
625 
626 	if (!pskb_network_may_pull(skb, thoff + hdrsize))
627 		return false;
628 
629 	switch (nexthdr) {
630 	case IPPROTO_TCP:
631 		*tcph = (void *)(skb_network_header(skb) + thoff);
632 		fallthrough;
633 	case IPPROTO_UDP:
634 		ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
635 		tuple->src_port = ports->source;
636 		tuple->dst_port = ports->dest;
637 		break;
638 	case IPPROTO_GRE: {
639 		struct gre_base_hdr *greh;
640 
641 		greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
642 		if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
643 			return false;
644 		break;
645 	}
646 	}
647 
648 	ip6h = ipv6_hdr(skb);
649 
650 	tuple->src_v6 = ip6h->saddr;
651 	tuple->dst_v6 = ip6h->daddr;
652 	tuple->l3proto = AF_INET6;
653 	tuple->l4proto = nexthdr;
654 
655 	return true;
656 }
657 
658 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
659 				     struct sk_buff *skb,
660 				     u8 family)
661 {
662 	struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
663 	struct flow_offload_tuple_rhash *tuplehash;
664 	struct flow_offload_tuple tuple = {};
665 	enum ip_conntrack_info ctinfo;
666 	struct tcphdr *tcph = NULL;
667 	bool force_refresh = false;
668 	struct flow_offload *flow;
669 	struct nf_conn *ct;
670 	u8 dir;
671 
672 	switch (family) {
673 	case NFPROTO_IPV4:
674 		if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
675 			return false;
676 		break;
677 	case NFPROTO_IPV6:
678 		if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
679 			return false;
680 		break;
681 	default:
682 		return false;
683 	}
684 
685 	tuplehash = flow_offload_lookup(nf_ft, &tuple);
686 	if (!tuplehash)
687 		return false;
688 
689 	dir = tuplehash->tuple.dir;
690 	flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
691 	ct = flow->ct;
692 
693 	if (dir == FLOW_OFFLOAD_DIR_REPLY &&
694 	    !test_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags)) {
695 		/* Only offload reply direction after connection became
696 		 * assured.
697 		 */
698 		if (test_bit(IPS_ASSURED_BIT, &ct->status))
699 			set_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags);
700 		else if (test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags))
701 			/* If flow_table flow has already been updated to the
702 			 * established state, then don't refresh.
703 			 */
704 			return false;
705 		force_refresh = true;
706 	}
707 
708 	if (tcph && (unlikely(tcph->fin || tcph->rst))) {
709 		flow_offload_teardown(flow);
710 		return false;
711 	}
712 
713 	if (dir == FLOW_OFFLOAD_DIR_ORIGINAL)
714 		ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ?
715 			IP_CT_ESTABLISHED : IP_CT_NEW;
716 	else
717 		ctinfo = IP_CT_ESTABLISHED_REPLY;
718 
719 	nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
720 	tcf_ct_flow_ct_ext_ifidx_update(flow);
721 	flow_offload_refresh(nf_ft, flow, force_refresh);
722 	if (!test_bit(IPS_ASSURED_BIT, &ct->status)) {
723 		/* Process this flow in SW to allow promoting to ASSURED */
724 		return false;
725 	}
726 
727 	nf_conntrack_get(&ct->ct_general);
728 	nf_ct_set(skb, ct, ctinfo);
729 	if (nf_ft->flags & NF_FLOWTABLE_COUNTER)
730 		nf_ct_acct_update(ct, dir, skb->len);
731 
732 	return true;
733 }
734 
735 static int tcf_ct_flow_tables_init(void)
736 {
737 	return rhashtable_init(&zones_ht, &zones_params);
738 }
739 
740 static void tcf_ct_flow_tables_uninit(void)
741 {
742 	rhashtable_destroy(&zones_ht);
743 }
744 
745 static struct tc_action_ops act_ct_ops;
746 
747 struct tc_ct_action_net {
748 	struct tc_action_net tn; /* Must be first */
749 };
750 
751 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
752 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
753 				   struct tcf_ct_params *p)
754 {
755 	enum ip_conntrack_info ctinfo;
756 	struct nf_conn *ct;
757 
758 	ct = nf_ct_get(skb, &ctinfo);
759 	if (!ct)
760 		return false;
761 	if (!net_eq(net, read_pnet(&ct->ct_net)))
762 		goto drop_ct;
763 	if (nf_ct_zone(ct)->id != p->zone)
764 		goto drop_ct;
765 	if (p->helper) {
766 		struct nf_conn_help *help;
767 
768 		help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
769 		if (help && rcu_access_pointer(help->helper) != p->helper)
770 			goto drop_ct;
771 	}
772 
773 	/* Force conntrack entry direction. */
774 	if ((p->ct_action & TCA_CT_ACT_FORCE) &&
775 	    CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
776 		if (nf_ct_is_confirmed(ct))
777 			nf_ct_kill(ct);
778 
779 		goto drop_ct;
780 	}
781 
782 	return true;
783 
784 drop_ct:
785 	nf_ct_put(ct);
786 	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
787 
788 	return false;
789 }
790 
791 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
792 {
793 	u8 family = NFPROTO_UNSPEC;
794 
795 	switch (skb_protocol(skb, true)) {
796 	case htons(ETH_P_IP):
797 		family = NFPROTO_IPV4;
798 		break;
799 	case htons(ETH_P_IPV6):
800 		family = NFPROTO_IPV6;
801 		break;
802 	default:
803 		break;
804 	}
805 
806 	return family;
807 }
808 
809 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
810 {
811 	unsigned int len;
812 
813 	len =  skb_network_offset(skb) + sizeof(struct iphdr);
814 	if (unlikely(skb->len < len))
815 		return -EINVAL;
816 	if (unlikely(!pskb_may_pull(skb, len)))
817 		return -ENOMEM;
818 
819 	*frag = ip_is_fragment(ip_hdr(skb));
820 	return 0;
821 }
822 
823 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
824 {
825 	unsigned int flags = 0, len, payload_ofs = 0;
826 	unsigned short frag_off;
827 	int nexthdr;
828 
829 	len =  skb_network_offset(skb) + sizeof(struct ipv6hdr);
830 	if (unlikely(skb->len < len))
831 		return -EINVAL;
832 	if (unlikely(!pskb_may_pull(skb, len)))
833 		return -ENOMEM;
834 
835 	nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
836 	if (unlikely(nexthdr < 0))
837 		return -EPROTO;
838 
839 	*frag = flags & IP6_FH_F_FRAG;
840 	return 0;
841 }
842 
843 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
844 				   u8 family, u16 zone, bool *defrag)
845 {
846 	enum ip_conntrack_info ctinfo;
847 	struct tc_skb_cb cb;
848 	struct nf_conn *ct;
849 	int err = 0;
850 	bool frag;
851 	u8 proto;
852 
853 	/* Previously seen (loopback)? Ignore. */
854 	ct = nf_ct_get(skb, &ctinfo);
855 	if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
856 		return 0;
857 
858 	if (family == NFPROTO_IPV4)
859 		err = tcf_ct_ipv4_is_fragment(skb, &frag);
860 	else
861 		err = tcf_ct_ipv6_is_fragment(skb, &frag);
862 	if (err || !frag)
863 		return err;
864 
865 	cb = *tc_skb_cb(skb);
866 	err = nf_ct_handle_fragments(net, skb, zone, family, &proto, &cb.mru);
867 	if (err)
868 		return err;
869 
870 	*defrag = true;
871 	*tc_skb_cb(skb) = cb;
872 
873 	return 0;
874 }
875 
876 static void tcf_ct_params_free(struct tcf_ct_params *params)
877 {
878 	if (params->helper) {
879 #if IS_ENABLED(CONFIG_NF_NAT)
880 		if (params->ct_action & TCA_CT_ACT_NAT)
881 			nf_nat_helper_put(params->helper);
882 #endif
883 		nf_conntrack_helper_put(params->helper);
884 	}
885 	if (params->ct_ft)
886 		tcf_ct_flow_table_put(params->ct_ft);
887 	if (params->tmpl) {
888 		if (params->put_labels)
889 			nf_connlabels_put(nf_ct_net(params->tmpl));
890 
891 		nf_ct_put(params->tmpl);
892 	}
893 
894 	kfree(params);
895 }
896 
897 static void tcf_ct_params_free_rcu(struct rcu_head *head)
898 {
899 	struct tcf_ct_params *params;
900 
901 	params = container_of(head, struct tcf_ct_params, rcu);
902 	tcf_ct_params_free(params);
903 }
904 
905 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
906 {
907 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
908 	u32 new_mark;
909 
910 	if (!mask)
911 		return;
912 
913 	new_mark = mark | (READ_ONCE(ct->mark) & ~(mask));
914 	if (READ_ONCE(ct->mark) != new_mark) {
915 		WRITE_ONCE(ct->mark, new_mark);
916 		if (nf_ct_is_confirmed(ct))
917 			nf_conntrack_event_cache(IPCT_MARK, ct);
918 	}
919 #endif
920 }
921 
922 static void tcf_ct_act_set_labels(struct nf_conn *ct,
923 				  u32 *labels,
924 				  u32 *labels_m)
925 {
926 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
927 	size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
928 
929 	if (!memchr_inv(labels_m, 0, labels_sz))
930 		return;
931 
932 	nf_connlabels_replace(ct, labels, labels_m, 4);
933 #endif
934 }
935 
936 static int tcf_ct_act_nat(struct sk_buff *skb,
937 			  struct nf_conn *ct,
938 			  enum ip_conntrack_info ctinfo,
939 			  int ct_action,
940 			  struct nf_nat_range2 *range,
941 			  bool commit)
942 {
943 #if IS_ENABLED(CONFIG_NF_NAT)
944 	int err, action = 0;
945 
946 	if (!(ct_action & TCA_CT_ACT_NAT))
947 		return NF_ACCEPT;
948 	if (ct_action & TCA_CT_ACT_NAT_SRC)
949 		action |= BIT(NF_NAT_MANIP_SRC);
950 	if (ct_action & TCA_CT_ACT_NAT_DST)
951 		action |= BIT(NF_NAT_MANIP_DST);
952 
953 	err = nf_ct_nat(skb, ct, ctinfo, &action, range, commit);
954 	if (err != NF_ACCEPT)
955 		return err & NF_VERDICT_MASK;
956 
957 	if (action & BIT(NF_NAT_MANIP_SRC))
958 		qdisc_skb_cb(skb)->post_ct_snat = 1;
959 	if (action & BIT(NF_NAT_MANIP_DST))
960 		qdisc_skb_cb(skb)->post_ct_dnat = 1;
961 
962 	return err;
963 #else
964 	return NF_ACCEPT;
965 #endif
966 }
967 
968 TC_INDIRECT_SCOPE int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
969 				 struct tcf_result *res)
970 {
971 	struct net *net = dev_net(skb->dev);
972 	enum ip_conntrack_info ctinfo;
973 	struct tcf_ct *c = to_ct(a);
974 	struct nf_conn *tmpl = NULL;
975 	struct nf_hook_state state;
976 	bool cached, commit, clear;
977 	int nh_ofs, err, retval;
978 	struct tcf_ct_params *p;
979 	bool add_helper = false;
980 	bool skip_add = false;
981 	bool defrag = false;
982 	struct nf_conn *ct;
983 	u8 family;
984 
985 	p = rcu_dereference_bh(c->params);
986 
987 	retval = p->action;
988 	commit = p->ct_action & TCA_CT_ACT_COMMIT;
989 	clear = p->ct_action & TCA_CT_ACT_CLEAR;
990 	tmpl = p->tmpl;
991 
992 	tcf_lastuse_update(&c->tcf_tm);
993 	tcf_action_update_bstats(&c->common, skb);
994 
995 	if (clear) {
996 		qdisc_skb_cb(skb)->post_ct = false;
997 		ct = nf_ct_get(skb, &ctinfo);
998 		if (ct) {
999 			nf_ct_put(ct);
1000 			nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
1001 		}
1002 
1003 		goto out_clear;
1004 	}
1005 
1006 	family = tcf_ct_skb_nf_family(skb);
1007 	if (family == NFPROTO_UNSPEC)
1008 		goto drop;
1009 
1010 	/* The conntrack module expects to be working at L3.
1011 	 * We also try to pull the IPv4/6 header to linear area
1012 	 */
1013 	nh_ofs = skb_network_offset(skb);
1014 	skb_pull_rcsum(skb, nh_ofs);
1015 	err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
1016 	if (err)
1017 		goto out_frag;
1018 
1019 	err = nf_ct_skb_network_trim(skb, family);
1020 	if (err)
1021 		goto drop;
1022 
1023 	/* If we are recirculating packets to match on ct fields and
1024 	 * committing with a separate ct action, then we don't need to
1025 	 * actually run the packet through conntrack twice unless it's for a
1026 	 * different zone.
1027 	 */
1028 	cached = tcf_ct_skb_nfct_cached(net, skb, p);
1029 	if (!cached) {
1030 		if (tcf_ct_flow_table_lookup(p, skb, family)) {
1031 			skip_add = true;
1032 			goto do_nat;
1033 		}
1034 
1035 		/* Associate skb with specified zone. */
1036 		if (tmpl) {
1037 			nf_conntrack_put(skb_nfct(skb));
1038 			nf_conntrack_get(&tmpl->ct_general);
1039 			nf_ct_set(skb, tmpl, IP_CT_NEW);
1040 		}
1041 
1042 		state.hook = NF_INET_PRE_ROUTING;
1043 		state.net = net;
1044 		state.pf = family;
1045 		err = nf_conntrack_in(skb, &state);
1046 		if (err != NF_ACCEPT)
1047 			goto nf_error;
1048 	}
1049 
1050 do_nat:
1051 	ct = nf_ct_get(skb, &ctinfo);
1052 	if (!ct)
1053 		goto out_push;
1054 	nf_ct_deliver_cached_events(ct);
1055 	nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
1056 
1057 	err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1058 	if (err != NF_ACCEPT)
1059 		goto nf_error;
1060 
1061 	if (!nf_ct_is_confirmed(ct) && commit && p->helper && !nfct_help(ct)) {
1062 		err = __nf_ct_try_assign_helper(ct, p->tmpl, GFP_ATOMIC);
1063 		if (err)
1064 			goto drop;
1065 		add_helper = true;
1066 		if (p->ct_action & TCA_CT_ACT_NAT && !nfct_seqadj(ct)) {
1067 			if (!nfct_seqadj_ext_add(ct))
1068 				goto drop;
1069 		}
1070 	}
1071 
1072 	if (nf_ct_is_confirmed(ct) ? ((!cached && !skip_add) || add_helper) : commit) {
1073 		err = nf_ct_helper(skb, ct, ctinfo, family);
1074 		if (err != NF_ACCEPT)
1075 			goto nf_error;
1076 	}
1077 
1078 	if (commit) {
1079 		tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1080 		tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1081 
1082 		if (!nf_ct_is_confirmed(ct))
1083 			nf_conn_act_ct_ext_add(skb, ct, ctinfo);
1084 
1085 		/* This will take care of sending queued events
1086 		 * even if the connection is already confirmed.
1087 		 */
1088 		err = nf_conntrack_confirm(skb);
1089 		if (err != NF_ACCEPT)
1090 			goto nf_error;
1091 
1092 		/* The ct may be dropped if a clash has been resolved,
1093 		 * so it's necessary to retrieve it from skb again to
1094 		 * prevent UAF.
1095 		 */
1096 		ct = nf_ct_get(skb, &ctinfo);
1097 		if (!ct)
1098 			skip_add = true;
1099 	}
1100 
1101 	if (!skip_add)
1102 		tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1103 
1104 out_push:
1105 	skb_push_rcsum(skb, nh_ofs);
1106 
1107 	qdisc_skb_cb(skb)->post_ct = true;
1108 	tc_skb_cb(skb)->zone = p->zone;
1109 out_clear:
1110 	if (defrag)
1111 		qdisc_skb_cb(skb)->pkt_len = skb->len;
1112 	return retval;
1113 
1114 out_frag:
1115 	if (err != -EINPROGRESS)
1116 		tcf_action_inc_drop_qstats(&c->common);
1117 	return TC_ACT_CONSUMED;
1118 
1119 drop:
1120 	tcf_action_inc_drop_qstats(&c->common);
1121 	return TC_ACT_SHOT;
1122 
1123 nf_error:
1124 	/* some verdicts store extra data in upper bits, such
1125 	 * as errno or queue number.
1126 	 */
1127 	switch (err & NF_VERDICT_MASK) {
1128 	case NF_DROP:
1129 		goto drop;
1130 	case NF_STOLEN:
1131 		tcf_action_inc_drop_qstats(&c->common);
1132 		return TC_ACT_CONSUMED;
1133 	default:
1134 		DEBUG_NET_WARN_ON_ONCE(1);
1135 		goto drop;
1136 	}
1137 }
1138 
1139 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1140 	[TCA_CT_ACTION] = { .type = NLA_U16 },
1141 	[TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)),
1142 	[TCA_CT_ZONE] = { .type = NLA_U16 },
1143 	[TCA_CT_MARK] = { .type = NLA_U32 },
1144 	[TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1145 	[TCA_CT_LABELS] = { .type = NLA_BINARY,
1146 			    .len = 128 / BITS_PER_BYTE },
1147 	[TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1148 				 .len = 128 / BITS_PER_BYTE },
1149 	[TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1150 	[TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1151 	[TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1152 	[TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1153 	[TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1154 	[TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1155 	[TCA_CT_HELPER_NAME] = { .type = NLA_STRING, .len = NF_CT_HELPER_NAME_LEN },
1156 	[TCA_CT_HELPER_FAMILY] = { .type = NLA_U8 },
1157 	[TCA_CT_HELPER_PROTO] = { .type = NLA_U8 },
1158 };
1159 
1160 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1161 				  struct tc_ct *parm,
1162 				  struct nlattr **tb,
1163 				  struct netlink_ext_ack *extack)
1164 {
1165 	struct nf_nat_range2 *range;
1166 
1167 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1168 		return 0;
1169 
1170 	if (!IS_ENABLED(CONFIG_NF_NAT)) {
1171 		NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1172 		return -EOPNOTSUPP;
1173 	}
1174 
1175 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1176 		return 0;
1177 
1178 	if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1179 	    (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1180 		NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1181 		return -EOPNOTSUPP;
1182 	}
1183 
1184 	range = &p->range;
1185 	if (tb[TCA_CT_NAT_IPV4_MIN]) {
1186 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1187 
1188 		p->ipv4_range = true;
1189 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1190 		range->min_addr.ip =
1191 			nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1192 
1193 		range->max_addr.ip =
1194 			nla_get_in_addr_default(max_attr, range->min_addr.ip);
1195 	} else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1196 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1197 
1198 		p->ipv4_range = false;
1199 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1200 		range->min_addr.in6 =
1201 			nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1202 
1203 		range->max_addr.in6 = max_attr ?
1204 				      nla_get_in6_addr(max_attr) :
1205 				      range->min_addr.in6;
1206 	}
1207 
1208 	if (tb[TCA_CT_NAT_PORT_MIN]) {
1209 		range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1210 		range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1211 
1212 		range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1213 				       nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1214 				       range->min_proto.all;
1215 	}
1216 
1217 	return 0;
1218 }
1219 
1220 static void tcf_ct_set_key_val(struct nlattr **tb,
1221 			       void *val, int val_type,
1222 			       void *mask, int mask_type,
1223 			       int len)
1224 {
1225 	if (!tb[val_type])
1226 		return;
1227 	nla_memcpy(val, tb[val_type], len);
1228 
1229 	if (!mask)
1230 		return;
1231 
1232 	if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1233 		memset(mask, 0xff, len);
1234 	else
1235 		nla_memcpy(mask, tb[mask_type], len);
1236 }
1237 
1238 static int tcf_ct_fill_params(struct net *net,
1239 			      struct tcf_ct_params *p,
1240 			      struct tc_ct *parm,
1241 			      struct nlattr **tb,
1242 			      struct netlink_ext_ack *extack)
1243 {
1244 	struct nf_conntrack_zone zone;
1245 	int err, family, proto, len;
1246 	bool put_labels = false;
1247 	struct nf_conn *tmpl;
1248 	char *name;
1249 
1250 	p->zone = NF_CT_DEFAULT_ZONE_ID;
1251 
1252 	tcf_ct_set_key_val(tb,
1253 			   &p->ct_action, TCA_CT_ACTION,
1254 			   NULL, TCA_CT_UNSPEC,
1255 			   sizeof(p->ct_action));
1256 
1257 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1258 		return 0;
1259 
1260 	err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1261 	if (err)
1262 		return err;
1263 
1264 	if (tb[TCA_CT_MARK]) {
1265 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1266 			NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1267 			return -EOPNOTSUPP;
1268 		}
1269 		tcf_ct_set_key_val(tb,
1270 				   &p->mark, TCA_CT_MARK,
1271 				   &p->mark_mask, TCA_CT_MARK_MASK,
1272 				   sizeof(p->mark));
1273 	}
1274 
1275 	if (tb[TCA_CT_LABELS]) {
1276 		unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1277 
1278 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1279 			NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1280 			return -EOPNOTSUPP;
1281 		}
1282 
1283 		if (nf_connlabels_get(net, n_bits - 1)) {
1284 			NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1285 			return -EOPNOTSUPP;
1286 		} else {
1287 			put_labels = true;
1288 		}
1289 
1290 		tcf_ct_set_key_val(tb,
1291 				   p->labels, TCA_CT_LABELS,
1292 				   p->labels_mask, TCA_CT_LABELS_MASK,
1293 				   sizeof(p->labels));
1294 	}
1295 
1296 	if (tb[TCA_CT_ZONE]) {
1297 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1298 			NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1299 			err = -EOPNOTSUPP;
1300 			goto err;
1301 		}
1302 
1303 		tcf_ct_set_key_val(tb,
1304 				   &p->zone, TCA_CT_ZONE,
1305 				   NULL, TCA_CT_UNSPEC,
1306 				   sizeof(p->zone));
1307 	}
1308 
1309 	nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1310 	tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1311 	if (!tmpl) {
1312 		NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1313 		err = -ENOMEM;
1314 		goto err;
1315 	}
1316 	p->tmpl = tmpl;
1317 	if (tb[TCA_CT_HELPER_NAME]) {
1318 		name = nla_data(tb[TCA_CT_HELPER_NAME]);
1319 		len = nla_len(tb[TCA_CT_HELPER_NAME]);
1320 		if (len > 16 || name[len - 1] != '\0') {
1321 			NL_SET_ERR_MSG_MOD(extack, "Failed to parse helper name.");
1322 			err = -EINVAL;
1323 			goto err;
1324 		}
1325 		family = nla_get_u8_default(tb[TCA_CT_HELPER_FAMILY], AF_INET);
1326 		proto = nla_get_u8_default(tb[TCA_CT_HELPER_PROTO],
1327 					   IPPROTO_TCP);
1328 		err = nf_ct_add_helper(tmpl, name, family, proto,
1329 				       p->ct_action & TCA_CT_ACT_NAT, &p->helper);
1330 		if (err) {
1331 			NL_SET_ERR_MSG_MOD(extack, "Failed to add helper");
1332 			goto err;
1333 		}
1334 	}
1335 
1336 	p->put_labels = put_labels;
1337 
1338 	if (p->ct_action & TCA_CT_ACT_COMMIT)
1339 		__set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1340 	return 0;
1341 err:
1342 	if (put_labels)
1343 		nf_connlabels_put(net);
1344 
1345 	nf_ct_put(p->tmpl);
1346 	p->tmpl = NULL;
1347 	return err;
1348 }
1349 
1350 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1351 		       struct nlattr *est, struct tc_action **a,
1352 		       struct tcf_proto *tp, u32 flags,
1353 		       struct netlink_ext_ack *extack)
1354 {
1355 	struct tc_action_net *tn = net_generic(net, act_ct_ops.net_id);
1356 	bool bind = flags & TCA_ACT_FLAGS_BIND;
1357 	struct tcf_ct_params *params = NULL;
1358 	struct nlattr *tb[TCA_CT_MAX + 1];
1359 	struct tcf_chain *goto_ch = NULL;
1360 	struct tc_ct *parm;
1361 	struct tcf_ct *c;
1362 	int err, res = 0;
1363 	u32 index;
1364 
1365 	if (!nla) {
1366 		NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1367 		return -EINVAL;
1368 	}
1369 
1370 	if (bind && !(flags & TCA_ACT_FLAGS_AT_INGRESS_OR_CLSACT)) {
1371 		NL_SET_ERR_MSG_MOD(extack,
1372 				   "Attaching ct to a non ingress/clsact qdisc is unsupported");
1373 		return -EOPNOTSUPP;
1374 	}
1375 
1376 	err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1377 	if (err < 0)
1378 		return err;
1379 
1380 	if (!tb[TCA_CT_PARMS]) {
1381 		NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1382 		return -EINVAL;
1383 	}
1384 	parm = nla_data(tb[TCA_CT_PARMS]);
1385 	index = parm->index;
1386 	err = tcf_idr_check_alloc(tn, &index, a, bind);
1387 	if (err < 0)
1388 		return err;
1389 
1390 	if (!err) {
1391 		err = tcf_idr_create_from_flags(tn, index, est, a,
1392 						&act_ct_ops, bind, flags);
1393 		if (err) {
1394 			tcf_idr_cleanup(tn, index);
1395 			return err;
1396 		}
1397 		res = ACT_P_CREATED;
1398 	} else {
1399 		if (bind)
1400 			return ACT_P_BOUND;
1401 
1402 		if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
1403 			tcf_idr_release(*a, bind);
1404 			return -EEXIST;
1405 		}
1406 	}
1407 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1408 	if (err < 0)
1409 		goto cleanup;
1410 
1411 	c = to_ct(*a);
1412 
1413 	params = kzalloc_obj(*params);
1414 	if (unlikely(!params)) {
1415 		err = -ENOMEM;
1416 		goto cleanup;
1417 	}
1418 
1419 	err = tcf_ct_fill_params(net, params, parm, tb, extack);
1420 	if (err)
1421 		goto cleanup;
1422 
1423 	err = tcf_ct_flow_table_get(net, params);
1424 	if (err)
1425 		goto cleanup;
1426 
1427 	params->action = parm->action;
1428 	spin_lock_bh(&c->tcf_lock);
1429 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1430 	params = rcu_replace_pointer(c->params, params,
1431 				     lockdep_is_held(&c->tcf_lock));
1432 	spin_unlock_bh(&c->tcf_lock);
1433 
1434 	if (goto_ch)
1435 		tcf_chain_put_by_act(goto_ch);
1436 	if (params)
1437 		call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1438 
1439 	return res;
1440 
1441 cleanup:
1442 	if (goto_ch)
1443 		tcf_chain_put_by_act(goto_ch);
1444 	if (params)
1445 		tcf_ct_params_free(params);
1446 	tcf_idr_release(*a, bind);
1447 	return err;
1448 }
1449 
1450 static void tcf_ct_cleanup(struct tc_action *a)
1451 {
1452 	struct tcf_ct_params *params;
1453 	struct tcf_ct *c = to_ct(a);
1454 
1455 	params = rcu_dereference_protected(c->params, 1);
1456 	if (params)
1457 		call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1458 }
1459 
1460 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1461 			       const void *val, int val_type,
1462 			       const void *mask, int mask_type,
1463 			       int len)
1464 {
1465 	int err;
1466 
1467 	if (mask && !memchr_inv(mask, 0, len))
1468 		return 0;
1469 
1470 	err = nla_put(skb, val_type, len, val);
1471 	if (err)
1472 		return err;
1473 
1474 	if (mask_type != TCA_CT_UNSPEC) {
1475 		err = nla_put(skb, mask_type, len, mask);
1476 		if (err)
1477 			return err;
1478 	}
1479 
1480 	return 0;
1481 }
1482 
1483 static int tcf_ct_dump_nat(struct sk_buff *skb, const struct tcf_ct_params *p)
1484 {
1485 	const struct nf_nat_range2 *range = &p->range;
1486 
1487 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1488 		return 0;
1489 
1490 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1491 		return 0;
1492 
1493 	if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1494 		if (p->ipv4_range) {
1495 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1496 					    range->min_addr.ip))
1497 				return -1;
1498 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1499 					    range->max_addr.ip))
1500 				return -1;
1501 		} else {
1502 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1503 					     &range->min_addr.in6))
1504 				return -1;
1505 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1506 					     &range->max_addr.in6))
1507 				return -1;
1508 		}
1509 	}
1510 
1511 	if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1512 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1513 				 range->min_proto.all))
1514 			return -1;
1515 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1516 				 range->max_proto.all))
1517 			return -1;
1518 	}
1519 
1520 	return 0;
1521 }
1522 
1523 static int tcf_ct_dump_helper(struct sk_buff *skb,
1524 			      const struct nf_conntrack_helper *helper)
1525 {
1526 	if (!helper)
1527 		return 0;
1528 
1529 	if (nla_put_string(skb, TCA_CT_HELPER_NAME, helper->name) ||
1530 	    nla_put_u8(skb, TCA_CT_HELPER_FAMILY, helper->tuple.src.l3num) ||
1531 	    nla_put_u8(skb, TCA_CT_HELPER_PROTO, helper->tuple.dst.protonum))
1532 		return -1;
1533 
1534 	return 0;
1535 }
1536 
1537 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1538 			      int bind, int ref)
1539 {
1540 	unsigned char *b = skb_tail_pointer(skb);
1541 	const struct tcf_ct *c = to_ct(a);
1542 	const struct tcf_ct_params *p;
1543 	struct tc_ct opt = {
1544 		.index   = c->tcf_index,
1545 		.refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1546 		.bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1547 	};
1548 	struct tcf_t t;
1549 
1550 	rcu_read_lock();
1551 	p = rcu_dereference(c->params);
1552 	opt.action = p->action;
1553 
1554 	if (tcf_ct_dump_key_val(skb,
1555 				&p->ct_action, TCA_CT_ACTION,
1556 				NULL, TCA_CT_UNSPEC,
1557 				sizeof(p->ct_action)))
1558 		goto nla_put_failure;
1559 
1560 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1561 		goto skip_dump;
1562 
1563 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1564 	    tcf_ct_dump_key_val(skb,
1565 				&p->mark, TCA_CT_MARK,
1566 				&p->mark_mask, TCA_CT_MARK_MASK,
1567 				sizeof(p->mark)))
1568 		goto nla_put_failure;
1569 
1570 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1571 	    tcf_ct_dump_key_val(skb,
1572 				p->labels, TCA_CT_LABELS,
1573 				p->labels_mask, TCA_CT_LABELS_MASK,
1574 				sizeof(p->labels)))
1575 		goto nla_put_failure;
1576 
1577 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1578 	    tcf_ct_dump_key_val(skb,
1579 				&p->zone, TCA_CT_ZONE,
1580 				NULL, TCA_CT_UNSPEC,
1581 				sizeof(p->zone)))
1582 		goto nla_put_failure;
1583 
1584 	if (tcf_ct_dump_nat(skb, p))
1585 		goto nla_put_failure;
1586 
1587 	if (tcf_ct_dump_helper(skb, p->helper))
1588 		goto nla_put_failure;
1589 
1590 skip_dump:
1591 	if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1592 		goto nla_put_failure;
1593 
1594 	tcf_tm_dump(&t, &c->tcf_tm);
1595 	if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1596 		goto nla_put_failure;
1597 	rcu_read_unlock();
1598 
1599 	return skb->len;
1600 nla_put_failure:
1601 	rcu_read_unlock();
1602 	nlmsg_trim(skb, b);
1603 	return -1;
1604 }
1605 
1606 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1607 			     u64 drops, u64 lastuse, bool hw)
1608 {
1609 	struct tcf_ct *c = to_ct(a);
1610 
1611 	tcf_action_update_stats(a, bytes, packets, drops, hw);
1612 	c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1613 }
1614 
1615 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data,
1616 				    u32 *index_inc, bool bind,
1617 				    struct netlink_ext_ack *extack)
1618 {
1619 	if (bind) {
1620 		struct flow_action_entry *entry = entry_data;
1621 
1622 		if (tcf_ct_helper(act))
1623 			return -EOPNOTSUPP;
1624 
1625 		entry->id = FLOW_ACTION_CT;
1626 		entry->ct.action = tcf_ct_action(act);
1627 		entry->ct.zone = tcf_ct_zone(act);
1628 		entry->ct.flow_table = tcf_ct_ft(act);
1629 		*index_inc = 1;
1630 	} else {
1631 		struct flow_offload_action *fl_action = entry_data;
1632 
1633 		fl_action->id = FLOW_ACTION_CT;
1634 	}
1635 
1636 	return 0;
1637 }
1638 
1639 static struct tc_action_ops act_ct_ops = {
1640 	.kind		=	"ct",
1641 	.id		=	TCA_ID_CT,
1642 	.owner		=	THIS_MODULE,
1643 	.act		=	tcf_ct_act,
1644 	.dump		=	tcf_ct_dump,
1645 	.init		=	tcf_ct_init,
1646 	.cleanup	=	tcf_ct_cleanup,
1647 	.stats_update	=	tcf_stats_update,
1648 	.offload_act_setup =	tcf_ct_offload_act_setup,
1649 	.size		=	sizeof(struct tcf_ct),
1650 };
1651 MODULE_ALIAS_NET_ACT("ct");
1652 
1653 static __net_init int ct_init_net(struct net *net)
1654 {
1655 	struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1656 
1657 	return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1658 }
1659 
1660 static void __net_exit ct_exit_net(struct list_head *net_list)
1661 {
1662 	tc_action_net_exit(net_list, act_ct_ops.net_id);
1663 }
1664 
1665 static struct pernet_operations ct_net_ops = {
1666 	.init = ct_init_net,
1667 	.exit_batch = ct_exit_net,
1668 	.id   = &act_ct_ops.net_id,
1669 	.size = sizeof(struct tc_ct_action_net),
1670 };
1671 
1672 static int __init ct_init_module(void)
1673 {
1674 	int err;
1675 
1676 	act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1677 	if (!act_ct_wq)
1678 		return -ENOMEM;
1679 
1680 	err = tcf_ct_flow_tables_init();
1681 	if (err)
1682 		goto err_tbl_init;
1683 
1684 	err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1685 	if (err)
1686 		goto err_register;
1687 
1688 	static_branch_inc(&tcf_frag_xmit_count);
1689 
1690 	return 0;
1691 
1692 err_register:
1693 	tcf_ct_flow_tables_uninit();
1694 err_tbl_init:
1695 	destroy_workqueue(act_ct_wq);
1696 	return err;
1697 }
1698 
1699 static void __exit ct_cleanup_module(void)
1700 {
1701 	static_branch_dec(&tcf_frag_xmit_count);
1702 	tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1703 	tcf_ct_flow_tables_uninit();
1704 	destroy_workqueue(act_ct_wq);
1705 }
1706 
1707 module_init(ct_init_module);
1708 module_exit(ct_cleanup_module);
1709 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1710 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1711 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1712 MODULE_DESCRIPTION("Connection tracking action");
1713 MODULE_LICENSE("GPL v2");
1714