xref: /linux/net/sched/act_ct.c (revision 6b8a024d25ebf7535eb4a3e926309aa693cfe1bd)
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/ip.h>
17 #include <linux/ipv6.h>
18 #include <linux/rhashtable.h>
19 #include <net/netlink.h>
20 #include <net/pkt_sched.h>
21 #include <net/pkt_cls.h>
22 #include <net/act_api.h>
23 #include <net/ip.h>
24 #include <net/ipv6_frag.h>
25 #include <uapi/linux/tc_act/tc_ct.h>
26 #include <net/tc_act/tc_ct.h>
27 #include <net/tc_wrapper.h>
28 
29 #include <net/netfilter/nf_flow_table.h>
30 #include <net/netfilter/nf_conntrack.h>
31 #include <net/netfilter/nf_conntrack_core.h>
32 #include <net/netfilter/nf_conntrack_zones.h>
33 #include <net/netfilter/nf_conntrack_helper.h>
34 #include <net/netfilter/nf_conntrack_acct.h>
35 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
36 #include <net/netfilter/nf_conntrack_act_ct.h>
37 #include <net/netfilter/nf_conntrack_seqadj.h>
38 #include <uapi/linux/netfilter/nf_nat.h>
39 
40 static struct workqueue_struct *act_ct_wq;
41 static struct rhashtable zones_ht;
42 static DEFINE_MUTEX(zones_mutex);
43 
44 struct zones_ht_key {
45 	struct net *net;
46 	u16 zone;
47 	/* Note : pad[] must be the last field. */
48 	u8  pad[];
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 = offsetof(struct zones_ht_key, pad),
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 	ct_ft = rhashtable_lookup_fast(&zones_ht, &key, zones_params);
332 	if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
333 		goto out_unlock;
334 
335 	ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
336 	if (!ct_ft)
337 		goto err_alloc;
338 	refcount_set(&ct_ft->ref, 1);
339 
340 	ct_ft->key = key;
341 	err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
342 	if (err)
343 		goto err_insert;
344 
345 	ct_ft->nf_ft.type = &flowtable_ct;
346 	ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD |
347 			      NF_FLOWTABLE_COUNTER;
348 	err = nf_flow_table_init(&ct_ft->nf_ft);
349 	if (err)
350 		goto err_init;
351 	write_pnet(&ct_ft->nf_ft.net, net);
352 
353 	__module_get(THIS_MODULE);
354 out_unlock:
355 	params->ct_ft = ct_ft;
356 	params->nf_ft = &ct_ft->nf_ft;
357 	mutex_unlock(&zones_mutex);
358 
359 	return 0;
360 
361 err_init:
362 	rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
363 err_insert:
364 	kfree(ct_ft);
365 err_alloc:
366 	mutex_unlock(&zones_mutex);
367 	return err;
368 }
369 
370 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft)
371 {
372 	refcount_inc(&ct_ft->ref);
373 }
374 
375 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
376 {
377 	struct tcf_ct_flow_table *ct_ft;
378 	struct flow_block *block;
379 
380 	ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
381 			     rwork);
382 	nf_flow_table_free(&ct_ft->nf_ft);
383 
384 	block = &ct_ft->nf_ft.flow_block;
385 	down_write(&ct_ft->nf_ft.flow_block_lock);
386 	WARN_ON(!list_empty(&block->cb_list));
387 	up_write(&ct_ft->nf_ft.flow_block_lock);
388 	kfree(ct_ft);
389 
390 	module_put(THIS_MODULE);
391 }
392 
393 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft)
394 {
395 	if (refcount_dec_and_test(&ct_ft->ref)) {
396 		rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
397 		INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
398 		queue_rcu_work(act_ct_wq, &ct_ft->rwork);
399 	}
400 }
401 
402 static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry,
403 				 struct nf_conn_act_ct_ext *act_ct_ext, u8 dir)
404 {
405 	entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC;
406 	entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir];
407 }
408 
409 static void tcf_ct_flow_ct_ext_ifidx_update(struct flow_offload *entry)
410 {
411 	struct nf_conn_act_ct_ext *act_ct_ext;
412 
413 	act_ct_ext = nf_conn_act_ct_ext_find(entry->ct);
414 	if (act_ct_ext) {
415 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
416 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
417 	}
418 }
419 
420 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
421 				  struct nf_conn *ct,
422 				  bool tcp, bool bidirectional)
423 {
424 	struct nf_conn_act_ct_ext *act_ct_ext;
425 	struct flow_offload *entry;
426 	int err;
427 
428 	if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
429 		return;
430 
431 	entry = flow_offload_alloc(ct);
432 	if (!entry) {
433 		WARN_ON_ONCE(1);
434 		goto err_alloc;
435 	}
436 
437 	if (tcp) {
438 		ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
439 		ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
440 	}
441 	if (bidirectional)
442 		__set_bit(NF_FLOW_HW_BIDIRECTIONAL, &entry->flags);
443 
444 	act_ct_ext = nf_conn_act_ct_ext_find(ct);
445 	if (act_ct_ext) {
446 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
447 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
448 	}
449 
450 	err = flow_offload_add(&ct_ft->nf_ft, entry);
451 	if (err)
452 		goto err_add;
453 
454 	return;
455 
456 err_add:
457 	flow_offload_free(entry);
458 err_alloc:
459 	clear_bit(IPS_OFFLOAD_BIT, &ct->status);
460 }
461 
462 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
463 					   struct nf_conn *ct,
464 					   enum ip_conntrack_info ctinfo)
465 {
466 	bool tcp = false, bidirectional = true;
467 
468 	switch (nf_ct_protonum(ct)) {
469 	case IPPROTO_TCP:
470 		if ((ctinfo != IP_CT_ESTABLISHED &&
471 		     ctinfo != IP_CT_ESTABLISHED_REPLY) ||
472 		    !test_bit(IPS_ASSURED_BIT, &ct->status) ||
473 		    ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
474 			return;
475 
476 		tcp = true;
477 		break;
478 	case IPPROTO_UDP:
479 		if (!nf_ct_is_confirmed(ct))
480 			return;
481 		if (!test_bit(IPS_ASSURED_BIT, &ct->status))
482 			bidirectional = false;
483 		break;
484 #ifdef CONFIG_NF_CT_PROTO_GRE
485 	case IPPROTO_GRE: {
486 		struct nf_conntrack_tuple *tuple;
487 
488 		if ((ctinfo != IP_CT_ESTABLISHED &&
489 		     ctinfo != IP_CT_ESTABLISHED_REPLY) ||
490 		    !test_bit(IPS_ASSURED_BIT, &ct->status) ||
491 		    ct->status & IPS_NAT_MASK)
492 			return;
493 
494 		tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
495 		/* No support for GRE v1 */
496 		if (tuple->src.u.gre.key || tuple->dst.u.gre.key)
497 			return;
498 		break;
499 	}
500 #endif
501 	default:
502 		return;
503 	}
504 
505 	if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
506 	    ct->status & IPS_SEQ_ADJUST)
507 		return;
508 
509 	tcf_ct_flow_table_add(ct_ft, ct, tcp, bidirectional);
510 }
511 
512 static bool
513 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
514 				  struct flow_offload_tuple *tuple,
515 				  struct tcphdr **tcph)
516 {
517 	struct flow_ports *ports;
518 	unsigned int thoff;
519 	struct iphdr *iph;
520 	size_t hdrsize;
521 	u8 ipproto;
522 
523 	if (!pskb_network_may_pull(skb, sizeof(*iph)))
524 		return false;
525 
526 	iph = ip_hdr(skb);
527 	thoff = iph->ihl * 4;
528 
529 	if (ip_is_fragment(iph) ||
530 	    unlikely(thoff != sizeof(struct iphdr)))
531 		return false;
532 
533 	ipproto = iph->protocol;
534 	switch (ipproto) {
535 	case IPPROTO_TCP:
536 		hdrsize = sizeof(struct tcphdr);
537 		break;
538 	case IPPROTO_UDP:
539 		hdrsize = sizeof(*ports);
540 		break;
541 #ifdef CONFIG_NF_CT_PROTO_GRE
542 	case IPPROTO_GRE:
543 		hdrsize = sizeof(struct gre_base_hdr);
544 		break;
545 #endif
546 	default:
547 		return false;
548 	}
549 
550 	if (iph->ttl <= 1)
551 		return false;
552 
553 	if (!pskb_network_may_pull(skb, thoff + hdrsize))
554 		return false;
555 
556 	switch (ipproto) {
557 	case IPPROTO_TCP:
558 		*tcph = (void *)(skb_network_header(skb) + thoff);
559 		fallthrough;
560 	case IPPROTO_UDP:
561 		ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
562 		tuple->src_port = ports->source;
563 		tuple->dst_port = ports->dest;
564 		break;
565 	case IPPROTO_GRE: {
566 		struct gre_base_hdr *greh;
567 
568 		greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
569 		if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
570 			return false;
571 		break;
572 	}
573 	}
574 
575 	iph = ip_hdr(skb);
576 
577 	tuple->src_v4.s_addr = iph->saddr;
578 	tuple->dst_v4.s_addr = iph->daddr;
579 	tuple->l3proto = AF_INET;
580 	tuple->l4proto = ipproto;
581 
582 	return true;
583 }
584 
585 static bool
586 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
587 				  struct flow_offload_tuple *tuple,
588 				  struct tcphdr **tcph)
589 {
590 	struct flow_ports *ports;
591 	struct ipv6hdr *ip6h;
592 	unsigned int thoff;
593 	size_t hdrsize;
594 	u8 nexthdr;
595 
596 	if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
597 		return false;
598 
599 	ip6h = ipv6_hdr(skb);
600 	thoff = sizeof(*ip6h);
601 
602 	nexthdr = ip6h->nexthdr;
603 	switch (nexthdr) {
604 	case IPPROTO_TCP:
605 		hdrsize = sizeof(struct tcphdr);
606 		break;
607 	case IPPROTO_UDP:
608 		hdrsize = sizeof(*ports);
609 		break;
610 #ifdef CONFIG_NF_CT_PROTO_GRE
611 	case IPPROTO_GRE:
612 		hdrsize = sizeof(struct gre_base_hdr);
613 		break;
614 #endif
615 	default:
616 		return false;
617 	}
618 
619 	if (ip6h->hop_limit <= 1)
620 		return false;
621 
622 	if (!pskb_network_may_pull(skb, thoff + hdrsize))
623 		return false;
624 
625 	switch (nexthdr) {
626 	case IPPROTO_TCP:
627 		*tcph = (void *)(skb_network_header(skb) + thoff);
628 		fallthrough;
629 	case IPPROTO_UDP:
630 		ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
631 		tuple->src_port = ports->source;
632 		tuple->dst_port = ports->dest;
633 		break;
634 	case IPPROTO_GRE: {
635 		struct gre_base_hdr *greh;
636 
637 		greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
638 		if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
639 			return false;
640 		break;
641 	}
642 	}
643 
644 	ip6h = ipv6_hdr(skb);
645 
646 	tuple->src_v6 = ip6h->saddr;
647 	tuple->dst_v6 = ip6h->daddr;
648 	tuple->l3proto = AF_INET6;
649 	tuple->l4proto = nexthdr;
650 
651 	return true;
652 }
653 
654 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
655 				     struct sk_buff *skb,
656 				     u8 family)
657 {
658 	struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
659 	struct flow_offload_tuple_rhash *tuplehash;
660 	struct flow_offload_tuple tuple = {};
661 	enum ip_conntrack_info ctinfo;
662 	struct tcphdr *tcph = NULL;
663 	bool force_refresh = false;
664 	struct flow_offload *flow;
665 	struct nf_conn *ct;
666 	u8 dir;
667 
668 	switch (family) {
669 	case NFPROTO_IPV4:
670 		if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
671 			return false;
672 		break;
673 	case NFPROTO_IPV6:
674 		if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
675 			return false;
676 		break;
677 	default:
678 		return false;
679 	}
680 
681 	tuplehash = flow_offload_lookup(nf_ft, &tuple);
682 	if (!tuplehash)
683 		return false;
684 
685 	dir = tuplehash->tuple.dir;
686 	flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
687 	ct = flow->ct;
688 
689 	if (dir == FLOW_OFFLOAD_DIR_REPLY &&
690 	    !test_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags)) {
691 		/* Only offload reply direction after connection became
692 		 * assured.
693 		 */
694 		if (test_bit(IPS_ASSURED_BIT, &ct->status))
695 			set_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags);
696 		else if (test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags))
697 			/* If flow_table flow has already been updated to the
698 			 * established state, then don't refresh.
699 			 */
700 			return false;
701 		force_refresh = true;
702 	}
703 
704 	if (tcph && (unlikely(tcph->fin || tcph->rst))) {
705 		flow_offload_teardown(flow);
706 		return false;
707 	}
708 
709 	if (dir == FLOW_OFFLOAD_DIR_ORIGINAL)
710 		ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ?
711 			IP_CT_ESTABLISHED : IP_CT_NEW;
712 	else
713 		ctinfo = IP_CT_ESTABLISHED_REPLY;
714 
715 	nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
716 	tcf_ct_flow_ct_ext_ifidx_update(flow);
717 	flow_offload_refresh(nf_ft, flow, force_refresh);
718 	if (!test_bit(IPS_ASSURED_BIT, &ct->status)) {
719 		/* Process this flow in SW to allow promoting to ASSURED */
720 		return false;
721 	}
722 
723 	nf_conntrack_get(&ct->ct_general);
724 	nf_ct_set(skb, ct, ctinfo);
725 	if (nf_ft->flags & NF_FLOWTABLE_COUNTER)
726 		nf_ct_acct_update(ct, dir, skb->len);
727 
728 	return true;
729 }
730 
731 static int tcf_ct_flow_tables_init(void)
732 {
733 	return rhashtable_init(&zones_ht, &zones_params);
734 }
735 
736 static void tcf_ct_flow_tables_uninit(void)
737 {
738 	rhashtable_destroy(&zones_ht);
739 }
740 
741 static struct tc_action_ops act_ct_ops;
742 
743 struct tc_ct_action_net {
744 	struct tc_action_net tn; /* Must be first */
745 };
746 
747 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
748 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
749 				   struct tcf_ct_params *p)
750 {
751 	enum ip_conntrack_info ctinfo;
752 	struct nf_conn *ct;
753 
754 	ct = nf_ct_get(skb, &ctinfo);
755 	if (!ct)
756 		return false;
757 	if (!net_eq(net, read_pnet(&ct->ct_net)))
758 		goto drop_ct;
759 	if (nf_ct_zone(ct)->id != p->zone)
760 		goto drop_ct;
761 	if (p->helper) {
762 		struct nf_conn_help *help;
763 
764 		help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
765 		if (help && rcu_access_pointer(help->helper) != p->helper)
766 			goto drop_ct;
767 	}
768 
769 	/* Force conntrack entry direction. */
770 	if ((p->ct_action & TCA_CT_ACT_FORCE) &&
771 	    CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
772 		if (nf_ct_is_confirmed(ct))
773 			nf_ct_kill(ct);
774 
775 		goto drop_ct;
776 	}
777 
778 	return true;
779 
780 drop_ct:
781 	nf_ct_put(ct);
782 	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
783 
784 	return false;
785 }
786 
787 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
788 {
789 	u8 family = NFPROTO_UNSPEC;
790 
791 	switch (skb_protocol(skb, true)) {
792 	case htons(ETH_P_IP):
793 		family = NFPROTO_IPV4;
794 		break;
795 	case htons(ETH_P_IPV6):
796 		family = NFPROTO_IPV6;
797 		break;
798 	default:
799 		break;
800 	}
801 
802 	return family;
803 }
804 
805 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
806 {
807 	unsigned int len;
808 
809 	len =  skb_network_offset(skb) + sizeof(struct iphdr);
810 	if (unlikely(skb->len < len))
811 		return -EINVAL;
812 	if (unlikely(!pskb_may_pull(skb, len)))
813 		return -ENOMEM;
814 
815 	*frag = ip_is_fragment(ip_hdr(skb));
816 	return 0;
817 }
818 
819 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
820 {
821 	unsigned int flags = 0, len, payload_ofs = 0;
822 	unsigned short frag_off;
823 	int nexthdr;
824 
825 	len =  skb_network_offset(skb) + sizeof(struct ipv6hdr);
826 	if (unlikely(skb->len < len))
827 		return -EINVAL;
828 	if (unlikely(!pskb_may_pull(skb, len)))
829 		return -ENOMEM;
830 
831 	nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
832 	if (unlikely(nexthdr < 0))
833 		return -EPROTO;
834 
835 	*frag = flags & IP6_FH_F_FRAG;
836 	return 0;
837 }
838 
839 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
840 				   u8 family, u16 zone, bool *defrag)
841 {
842 	enum ip_conntrack_info ctinfo;
843 	struct nf_conn *ct;
844 	int err = 0;
845 	bool frag;
846 	u8 proto;
847 	u16 mru;
848 
849 	/* Previously seen (loopback)? Ignore. */
850 	ct = nf_ct_get(skb, &ctinfo);
851 	if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
852 		return 0;
853 
854 	if (family == NFPROTO_IPV4)
855 		err = tcf_ct_ipv4_is_fragment(skb, &frag);
856 	else
857 		err = tcf_ct_ipv6_is_fragment(skb, &frag);
858 	if (err || !frag)
859 		return err;
860 
861 	err = nf_ct_handle_fragments(net, skb, zone, family, &proto, &mru);
862 	if (err)
863 		return err;
864 
865 	*defrag = true;
866 	tc_skb_cb(skb)->mru = mru;
867 
868 	return 0;
869 }
870 
871 static void tcf_ct_params_free(struct tcf_ct_params *params)
872 {
873 	if (params->helper) {
874 #if IS_ENABLED(CONFIG_NF_NAT)
875 		if (params->ct_action & TCA_CT_ACT_NAT)
876 			nf_nat_helper_put(params->helper);
877 #endif
878 		nf_conntrack_helper_put(params->helper);
879 	}
880 	if (params->ct_ft)
881 		tcf_ct_flow_table_put(params->ct_ft);
882 	if (params->tmpl) {
883 		if (params->put_labels)
884 			nf_connlabels_put(nf_ct_net(params->tmpl));
885 
886 		nf_ct_put(params->tmpl);
887 	}
888 
889 	kfree(params);
890 }
891 
892 static void tcf_ct_params_free_rcu(struct rcu_head *head)
893 {
894 	struct tcf_ct_params *params;
895 
896 	params = container_of(head, struct tcf_ct_params, rcu);
897 	tcf_ct_params_free(params);
898 }
899 
900 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
901 {
902 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
903 	u32 new_mark;
904 
905 	if (!mask)
906 		return;
907 
908 	new_mark = mark | (READ_ONCE(ct->mark) & ~(mask));
909 	if (READ_ONCE(ct->mark) != new_mark) {
910 		WRITE_ONCE(ct->mark, new_mark);
911 		if (nf_ct_is_confirmed(ct))
912 			nf_conntrack_event_cache(IPCT_MARK, ct);
913 	}
914 #endif
915 }
916 
917 static void tcf_ct_act_set_labels(struct nf_conn *ct,
918 				  u32 *labels,
919 				  u32 *labels_m)
920 {
921 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
922 	size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
923 
924 	if (!memchr_inv(labels_m, 0, labels_sz))
925 		return;
926 
927 	nf_connlabels_replace(ct, labels, labels_m, 4);
928 #endif
929 }
930 
931 static int tcf_ct_act_nat(struct sk_buff *skb,
932 			  struct nf_conn *ct,
933 			  enum ip_conntrack_info ctinfo,
934 			  int ct_action,
935 			  struct nf_nat_range2 *range,
936 			  bool commit)
937 {
938 #if IS_ENABLED(CONFIG_NF_NAT)
939 	int err, action = 0;
940 
941 	if (!(ct_action & TCA_CT_ACT_NAT))
942 		return NF_ACCEPT;
943 	if (ct_action & TCA_CT_ACT_NAT_SRC)
944 		action |= BIT(NF_NAT_MANIP_SRC);
945 	if (ct_action & TCA_CT_ACT_NAT_DST)
946 		action |= BIT(NF_NAT_MANIP_DST);
947 
948 	err = nf_ct_nat(skb, ct, ctinfo, &action, range, commit);
949 	if (err != NF_ACCEPT)
950 		return err & NF_VERDICT_MASK;
951 
952 	if (action & BIT(NF_NAT_MANIP_SRC))
953 		tc_skb_cb(skb)->post_ct_snat = 1;
954 	if (action & BIT(NF_NAT_MANIP_DST))
955 		tc_skb_cb(skb)->post_ct_dnat = 1;
956 
957 	return err;
958 #else
959 	return NF_ACCEPT;
960 #endif
961 }
962 
963 TC_INDIRECT_SCOPE int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
964 				 struct tcf_result *res)
965 {
966 	struct net *net = dev_net(skb->dev);
967 	enum ip_conntrack_info ctinfo;
968 	struct tcf_ct *c = to_ct(a);
969 	struct nf_conn *tmpl = NULL;
970 	struct nf_hook_state state;
971 	bool cached, commit, clear;
972 	int nh_ofs, err, retval;
973 	struct tcf_ct_params *p;
974 	bool add_helper = false;
975 	bool skip_add = false;
976 	bool defrag = false;
977 	struct nf_conn *ct;
978 	u8 family;
979 
980 	p = rcu_dereference_bh(c->params);
981 
982 	retval = READ_ONCE(c->tcf_action);
983 	commit = p->ct_action & TCA_CT_ACT_COMMIT;
984 	clear = p->ct_action & TCA_CT_ACT_CLEAR;
985 	tmpl = p->tmpl;
986 
987 	tcf_lastuse_update(&c->tcf_tm);
988 	tcf_action_update_bstats(&c->common, skb);
989 
990 	if (clear) {
991 		tc_skb_cb(skb)->post_ct = false;
992 		ct = nf_ct_get(skb, &ctinfo);
993 		if (ct) {
994 			nf_ct_put(ct);
995 			nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
996 		}
997 
998 		goto out_clear;
999 	}
1000 
1001 	family = tcf_ct_skb_nf_family(skb);
1002 	if (family == NFPROTO_UNSPEC)
1003 		goto drop;
1004 
1005 	/* The conntrack module expects to be working at L3.
1006 	 * We also try to pull the IPv4/6 header to linear area
1007 	 */
1008 	nh_ofs = skb_network_offset(skb);
1009 	skb_pull_rcsum(skb, nh_ofs);
1010 	err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
1011 	if (err)
1012 		goto out_frag;
1013 
1014 	err = nf_ct_skb_network_trim(skb, family);
1015 	if (err)
1016 		goto drop;
1017 
1018 	/* If we are recirculating packets to match on ct fields and
1019 	 * committing with a separate ct action, then we don't need to
1020 	 * actually run the packet through conntrack twice unless it's for a
1021 	 * different zone.
1022 	 */
1023 	cached = tcf_ct_skb_nfct_cached(net, skb, p);
1024 	if (!cached) {
1025 		if (tcf_ct_flow_table_lookup(p, skb, family)) {
1026 			skip_add = true;
1027 			goto do_nat;
1028 		}
1029 
1030 		/* Associate skb with specified zone. */
1031 		if (tmpl) {
1032 			nf_conntrack_put(skb_nfct(skb));
1033 			nf_conntrack_get(&tmpl->ct_general);
1034 			nf_ct_set(skb, tmpl, IP_CT_NEW);
1035 		}
1036 
1037 		state.hook = NF_INET_PRE_ROUTING;
1038 		state.net = net;
1039 		state.pf = family;
1040 		err = nf_conntrack_in(skb, &state);
1041 		if (err != NF_ACCEPT)
1042 			goto nf_error;
1043 	}
1044 
1045 do_nat:
1046 	ct = nf_ct_get(skb, &ctinfo);
1047 	if (!ct)
1048 		goto out_push;
1049 	nf_ct_deliver_cached_events(ct);
1050 	nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
1051 
1052 	err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1053 	if (err != NF_ACCEPT)
1054 		goto nf_error;
1055 
1056 	if (!nf_ct_is_confirmed(ct) && commit && p->helper && !nfct_help(ct)) {
1057 		err = __nf_ct_try_assign_helper(ct, p->tmpl, GFP_ATOMIC);
1058 		if (err)
1059 			goto drop;
1060 		add_helper = true;
1061 		if (p->ct_action & TCA_CT_ACT_NAT && !nfct_seqadj(ct)) {
1062 			if (!nfct_seqadj_ext_add(ct))
1063 				goto drop;
1064 		}
1065 	}
1066 
1067 	if (nf_ct_is_confirmed(ct) ? ((!cached && !skip_add) || add_helper) : commit) {
1068 		err = nf_ct_helper(skb, ct, ctinfo, family);
1069 		if (err != NF_ACCEPT)
1070 			goto nf_error;
1071 	}
1072 
1073 	if (commit) {
1074 		tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1075 		tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1076 
1077 		if (!nf_ct_is_confirmed(ct))
1078 			nf_conn_act_ct_ext_add(skb, ct, ctinfo);
1079 
1080 		/* This will take care of sending queued events
1081 		 * even if the connection is already confirmed.
1082 		 */
1083 		err = nf_conntrack_confirm(skb);
1084 		if (err != NF_ACCEPT)
1085 			goto nf_error;
1086 
1087 		/* The ct may be dropped if a clash has been resolved,
1088 		 * so it's necessary to retrieve it from skb again to
1089 		 * prevent UAF.
1090 		 */
1091 		ct = nf_ct_get(skb, &ctinfo);
1092 		if (!ct)
1093 			skip_add = true;
1094 	}
1095 
1096 	if (!skip_add)
1097 		tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1098 
1099 out_push:
1100 	skb_push_rcsum(skb, nh_ofs);
1101 
1102 	tc_skb_cb(skb)->post_ct = true;
1103 	tc_skb_cb(skb)->zone = p->zone;
1104 out_clear:
1105 	if (defrag)
1106 		qdisc_skb_cb(skb)->pkt_len = skb->len;
1107 	return retval;
1108 
1109 out_frag:
1110 	if (err != -EINPROGRESS)
1111 		tcf_action_inc_drop_qstats(&c->common);
1112 	return TC_ACT_CONSUMED;
1113 
1114 drop:
1115 	tcf_action_inc_drop_qstats(&c->common);
1116 	return TC_ACT_SHOT;
1117 
1118 nf_error:
1119 	/* some verdicts store extra data in upper bits, such
1120 	 * as errno or queue number.
1121 	 */
1122 	switch (err & NF_VERDICT_MASK) {
1123 	case NF_DROP:
1124 		goto drop;
1125 	case NF_STOLEN:
1126 		tcf_action_inc_drop_qstats(&c->common);
1127 		return TC_ACT_CONSUMED;
1128 	default:
1129 		DEBUG_NET_WARN_ON_ONCE(1);
1130 		goto drop;
1131 	}
1132 }
1133 
1134 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1135 	[TCA_CT_ACTION] = { .type = NLA_U16 },
1136 	[TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)),
1137 	[TCA_CT_ZONE] = { .type = NLA_U16 },
1138 	[TCA_CT_MARK] = { .type = NLA_U32 },
1139 	[TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1140 	[TCA_CT_LABELS] = { .type = NLA_BINARY,
1141 			    .len = 128 / BITS_PER_BYTE },
1142 	[TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1143 				 .len = 128 / BITS_PER_BYTE },
1144 	[TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1145 	[TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1146 	[TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1147 	[TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1148 	[TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1149 	[TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1150 	[TCA_CT_HELPER_NAME] = { .type = NLA_STRING, .len = NF_CT_HELPER_NAME_LEN },
1151 	[TCA_CT_HELPER_FAMILY] = { .type = NLA_U8 },
1152 	[TCA_CT_HELPER_PROTO] = { .type = NLA_U8 },
1153 };
1154 
1155 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1156 				  struct tc_ct *parm,
1157 				  struct nlattr **tb,
1158 				  struct netlink_ext_ack *extack)
1159 {
1160 	struct nf_nat_range2 *range;
1161 
1162 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1163 		return 0;
1164 
1165 	if (!IS_ENABLED(CONFIG_NF_NAT)) {
1166 		NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1167 		return -EOPNOTSUPP;
1168 	}
1169 
1170 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1171 		return 0;
1172 
1173 	if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1174 	    (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1175 		NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1176 		return -EOPNOTSUPP;
1177 	}
1178 
1179 	range = &p->range;
1180 	if (tb[TCA_CT_NAT_IPV4_MIN]) {
1181 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1182 
1183 		p->ipv4_range = true;
1184 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1185 		range->min_addr.ip =
1186 			nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1187 
1188 		range->max_addr.ip = max_attr ?
1189 				     nla_get_in_addr(max_attr) :
1190 				     range->min_addr.ip;
1191 	} else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1192 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1193 
1194 		p->ipv4_range = false;
1195 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1196 		range->min_addr.in6 =
1197 			nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1198 
1199 		range->max_addr.in6 = max_attr ?
1200 				      nla_get_in6_addr(max_attr) :
1201 				      range->min_addr.in6;
1202 	}
1203 
1204 	if (tb[TCA_CT_NAT_PORT_MIN]) {
1205 		range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1206 		range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1207 
1208 		range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1209 				       nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1210 				       range->min_proto.all;
1211 	}
1212 
1213 	return 0;
1214 }
1215 
1216 static void tcf_ct_set_key_val(struct nlattr **tb,
1217 			       void *val, int val_type,
1218 			       void *mask, int mask_type,
1219 			       int len)
1220 {
1221 	if (!tb[val_type])
1222 		return;
1223 	nla_memcpy(val, tb[val_type], len);
1224 
1225 	if (!mask)
1226 		return;
1227 
1228 	if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1229 		memset(mask, 0xff, len);
1230 	else
1231 		nla_memcpy(mask, tb[mask_type], len);
1232 }
1233 
1234 static int tcf_ct_fill_params(struct net *net,
1235 			      struct tcf_ct_params *p,
1236 			      struct tc_ct *parm,
1237 			      struct nlattr **tb,
1238 			      struct netlink_ext_ack *extack)
1239 {
1240 	struct nf_conntrack_zone zone;
1241 	int err, family, proto, len;
1242 	bool put_labels = false;
1243 	struct nf_conn *tmpl;
1244 	char *name;
1245 
1246 	p->zone = NF_CT_DEFAULT_ZONE_ID;
1247 
1248 	tcf_ct_set_key_val(tb,
1249 			   &p->ct_action, TCA_CT_ACTION,
1250 			   NULL, TCA_CT_UNSPEC,
1251 			   sizeof(p->ct_action));
1252 
1253 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1254 		return 0;
1255 
1256 	err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1257 	if (err)
1258 		return err;
1259 
1260 	if (tb[TCA_CT_MARK]) {
1261 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1262 			NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1263 			return -EOPNOTSUPP;
1264 		}
1265 		tcf_ct_set_key_val(tb,
1266 				   &p->mark, TCA_CT_MARK,
1267 				   &p->mark_mask, TCA_CT_MARK_MASK,
1268 				   sizeof(p->mark));
1269 	}
1270 
1271 	if (tb[TCA_CT_LABELS]) {
1272 		unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1273 
1274 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1275 			NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1276 			return -EOPNOTSUPP;
1277 		}
1278 
1279 		if (nf_connlabels_get(net, n_bits - 1)) {
1280 			NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1281 			return -EOPNOTSUPP;
1282 		} else {
1283 			put_labels = true;
1284 		}
1285 
1286 		tcf_ct_set_key_val(tb,
1287 				   p->labels, TCA_CT_LABELS,
1288 				   p->labels_mask, TCA_CT_LABELS_MASK,
1289 				   sizeof(p->labels));
1290 	}
1291 
1292 	if (tb[TCA_CT_ZONE]) {
1293 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1294 			NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1295 			return -EOPNOTSUPP;
1296 		}
1297 
1298 		tcf_ct_set_key_val(tb,
1299 				   &p->zone, TCA_CT_ZONE,
1300 				   NULL, TCA_CT_UNSPEC,
1301 				   sizeof(p->zone));
1302 	}
1303 
1304 	nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1305 	tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1306 	if (!tmpl) {
1307 		NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1308 		return -ENOMEM;
1309 	}
1310 	p->tmpl = tmpl;
1311 	if (tb[TCA_CT_HELPER_NAME]) {
1312 		name = nla_data(tb[TCA_CT_HELPER_NAME]);
1313 		len = nla_len(tb[TCA_CT_HELPER_NAME]);
1314 		if (len > 16 || name[len - 1] != '\0') {
1315 			NL_SET_ERR_MSG_MOD(extack, "Failed to parse helper name.");
1316 			err = -EINVAL;
1317 			goto err;
1318 		}
1319 		family = tb[TCA_CT_HELPER_FAMILY] ? nla_get_u8(tb[TCA_CT_HELPER_FAMILY]) : AF_INET;
1320 		proto = tb[TCA_CT_HELPER_PROTO] ? nla_get_u8(tb[TCA_CT_HELPER_PROTO]) : IPPROTO_TCP;
1321 		err = nf_ct_add_helper(tmpl, name, family, proto,
1322 				       p->ct_action & TCA_CT_ACT_NAT, &p->helper);
1323 		if (err) {
1324 			NL_SET_ERR_MSG_MOD(extack, "Failed to add helper");
1325 			goto err;
1326 		}
1327 	}
1328 
1329 	p->put_labels = put_labels;
1330 
1331 	if (p->ct_action & TCA_CT_ACT_COMMIT)
1332 		__set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1333 	return 0;
1334 err:
1335 	if (put_labels)
1336 		nf_connlabels_put(net);
1337 
1338 	nf_ct_put(p->tmpl);
1339 	p->tmpl = NULL;
1340 	return err;
1341 }
1342 
1343 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1344 		       struct nlattr *est, struct tc_action **a,
1345 		       struct tcf_proto *tp, u32 flags,
1346 		       struct netlink_ext_ack *extack)
1347 {
1348 	struct tc_action_net *tn = net_generic(net, act_ct_ops.net_id);
1349 	bool bind = flags & TCA_ACT_FLAGS_BIND;
1350 	struct tcf_ct_params *params = NULL;
1351 	struct nlattr *tb[TCA_CT_MAX + 1];
1352 	struct tcf_chain *goto_ch = NULL;
1353 	struct tc_ct *parm;
1354 	struct tcf_ct *c;
1355 	int err, res = 0;
1356 	u32 index;
1357 
1358 	if (!nla) {
1359 		NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1360 		return -EINVAL;
1361 	}
1362 
1363 	err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1364 	if (err < 0)
1365 		return err;
1366 
1367 	if (!tb[TCA_CT_PARMS]) {
1368 		NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1369 		return -EINVAL;
1370 	}
1371 	parm = nla_data(tb[TCA_CT_PARMS]);
1372 	index = parm->index;
1373 	err = tcf_idr_check_alloc(tn, &index, a, bind);
1374 	if (err < 0)
1375 		return err;
1376 
1377 	if (!err) {
1378 		err = tcf_idr_create_from_flags(tn, index, est, a,
1379 						&act_ct_ops, bind, flags);
1380 		if (err) {
1381 			tcf_idr_cleanup(tn, index);
1382 			return err;
1383 		}
1384 		res = ACT_P_CREATED;
1385 	} else {
1386 		if (bind)
1387 			return ACT_P_BOUND;
1388 
1389 		if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
1390 			tcf_idr_release(*a, bind);
1391 			return -EEXIST;
1392 		}
1393 	}
1394 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1395 	if (err < 0)
1396 		goto cleanup;
1397 
1398 	c = to_ct(*a);
1399 
1400 	params = kzalloc(sizeof(*params), GFP_KERNEL);
1401 	if (unlikely(!params)) {
1402 		err = -ENOMEM;
1403 		goto cleanup;
1404 	}
1405 
1406 	err = tcf_ct_fill_params(net, params, parm, tb, extack);
1407 	if (err)
1408 		goto cleanup;
1409 
1410 	err = tcf_ct_flow_table_get(net, params);
1411 	if (err)
1412 		goto cleanup;
1413 
1414 	spin_lock_bh(&c->tcf_lock);
1415 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1416 	params = rcu_replace_pointer(c->params, params,
1417 				     lockdep_is_held(&c->tcf_lock));
1418 	spin_unlock_bh(&c->tcf_lock);
1419 
1420 	if (goto_ch)
1421 		tcf_chain_put_by_act(goto_ch);
1422 	if (params)
1423 		call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1424 
1425 	return res;
1426 
1427 cleanup:
1428 	if (goto_ch)
1429 		tcf_chain_put_by_act(goto_ch);
1430 	if (params)
1431 		tcf_ct_params_free(params);
1432 	tcf_idr_release(*a, bind);
1433 	return err;
1434 }
1435 
1436 static void tcf_ct_cleanup(struct tc_action *a)
1437 {
1438 	struct tcf_ct_params *params;
1439 	struct tcf_ct *c = to_ct(a);
1440 
1441 	params = rcu_dereference_protected(c->params, 1);
1442 	if (params)
1443 		call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1444 }
1445 
1446 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1447 			       void *val, int val_type,
1448 			       void *mask, int mask_type,
1449 			       int len)
1450 {
1451 	int err;
1452 
1453 	if (mask && !memchr_inv(mask, 0, len))
1454 		return 0;
1455 
1456 	err = nla_put(skb, val_type, len, val);
1457 	if (err)
1458 		return err;
1459 
1460 	if (mask_type != TCA_CT_UNSPEC) {
1461 		err = nla_put(skb, mask_type, len, mask);
1462 		if (err)
1463 			return err;
1464 	}
1465 
1466 	return 0;
1467 }
1468 
1469 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1470 {
1471 	struct nf_nat_range2 *range = &p->range;
1472 
1473 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1474 		return 0;
1475 
1476 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1477 		return 0;
1478 
1479 	if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1480 		if (p->ipv4_range) {
1481 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1482 					    range->min_addr.ip))
1483 				return -1;
1484 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1485 					    range->max_addr.ip))
1486 				return -1;
1487 		} else {
1488 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1489 					     &range->min_addr.in6))
1490 				return -1;
1491 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1492 					     &range->max_addr.in6))
1493 				return -1;
1494 		}
1495 	}
1496 
1497 	if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1498 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1499 				 range->min_proto.all))
1500 			return -1;
1501 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1502 				 range->max_proto.all))
1503 			return -1;
1504 	}
1505 
1506 	return 0;
1507 }
1508 
1509 static int tcf_ct_dump_helper(struct sk_buff *skb, struct nf_conntrack_helper *helper)
1510 {
1511 	if (!helper)
1512 		return 0;
1513 
1514 	if (nla_put_string(skb, TCA_CT_HELPER_NAME, helper->name) ||
1515 	    nla_put_u8(skb, TCA_CT_HELPER_FAMILY, helper->tuple.src.l3num) ||
1516 	    nla_put_u8(skb, TCA_CT_HELPER_PROTO, helper->tuple.dst.protonum))
1517 		return -1;
1518 
1519 	return 0;
1520 }
1521 
1522 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1523 			      int bind, int ref)
1524 {
1525 	unsigned char *b = skb_tail_pointer(skb);
1526 	struct tcf_ct *c = to_ct(a);
1527 	struct tcf_ct_params *p;
1528 
1529 	struct tc_ct opt = {
1530 		.index   = c->tcf_index,
1531 		.refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1532 		.bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1533 	};
1534 	struct tcf_t t;
1535 
1536 	spin_lock_bh(&c->tcf_lock);
1537 	p = rcu_dereference_protected(c->params,
1538 				      lockdep_is_held(&c->tcf_lock));
1539 	opt.action = c->tcf_action;
1540 
1541 	if (tcf_ct_dump_key_val(skb,
1542 				&p->ct_action, TCA_CT_ACTION,
1543 				NULL, TCA_CT_UNSPEC,
1544 				sizeof(p->ct_action)))
1545 		goto nla_put_failure;
1546 
1547 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1548 		goto skip_dump;
1549 
1550 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1551 	    tcf_ct_dump_key_val(skb,
1552 				&p->mark, TCA_CT_MARK,
1553 				&p->mark_mask, TCA_CT_MARK_MASK,
1554 				sizeof(p->mark)))
1555 		goto nla_put_failure;
1556 
1557 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1558 	    tcf_ct_dump_key_val(skb,
1559 				p->labels, TCA_CT_LABELS,
1560 				p->labels_mask, TCA_CT_LABELS_MASK,
1561 				sizeof(p->labels)))
1562 		goto nla_put_failure;
1563 
1564 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1565 	    tcf_ct_dump_key_val(skb,
1566 				&p->zone, TCA_CT_ZONE,
1567 				NULL, TCA_CT_UNSPEC,
1568 				sizeof(p->zone)))
1569 		goto nla_put_failure;
1570 
1571 	if (tcf_ct_dump_nat(skb, p))
1572 		goto nla_put_failure;
1573 
1574 	if (tcf_ct_dump_helper(skb, p->helper))
1575 		goto nla_put_failure;
1576 
1577 skip_dump:
1578 	if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1579 		goto nla_put_failure;
1580 
1581 	tcf_tm_dump(&t, &c->tcf_tm);
1582 	if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1583 		goto nla_put_failure;
1584 	spin_unlock_bh(&c->tcf_lock);
1585 
1586 	return skb->len;
1587 nla_put_failure:
1588 	spin_unlock_bh(&c->tcf_lock);
1589 	nlmsg_trim(skb, b);
1590 	return -1;
1591 }
1592 
1593 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1594 			     u64 drops, u64 lastuse, bool hw)
1595 {
1596 	struct tcf_ct *c = to_ct(a);
1597 
1598 	tcf_action_update_stats(a, bytes, packets, drops, hw);
1599 	c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1600 }
1601 
1602 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data,
1603 				    u32 *index_inc, bool bind,
1604 				    struct netlink_ext_ack *extack)
1605 {
1606 	if (bind) {
1607 		struct flow_action_entry *entry = entry_data;
1608 
1609 		if (tcf_ct_helper(act))
1610 			return -EOPNOTSUPP;
1611 
1612 		entry->id = FLOW_ACTION_CT;
1613 		entry->ct.action = tcf_ct_action(act);
1614 		entry->ct.zone = tcf_ct_zone(act);
1615 		entry->ct.flow_table = tcf_ct_ft(act);
1616 		*index_inc = 1;
1617 	} else {
1618 		struct flow_offload_action *fl_action = entry_data;
1619 
1620 		fl_action->id = FLOW_ACTION_CT;
1621 	}
1622 
1623 	return 0;
1624 }
1625 
1626 static struct tc_action_ops act_ct_ops = {
1627 	.kind		=	"ct",
1628 	.id		=	TCA_ID_CT,
1629 	.owner		=	THIS_MODULE,
1630 	.act		=	tcf_ct_act,
1631 	.dump		=	tcf_ct_dump,
1632 	.init		=	tcf_ct_init,
1633 	.cleanup	=	tcf_ct_cleanup,
1634 	.stats_update	=	tcf_stats_update,
1635 	.offload_act_setup =	tcf_ct_offload_act_setup,
1636 	.size		=	sizeof(struct tcf_ct),
1637 };
1638 MODULE_ALIAS_NET_ACT("ct");
1639 
1640 static __net_init int ct_init_net(struct net *net)
1641 {
1642 	struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1643 
1644 	return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1645 }
1646 
1647 static void __net_exit ct_exit_net(struct list_head *net_list)
1648 {
1649 	tc_action_net_exit(net_list, act_ct_ops.net_id);
1650 }
1651 
1652 static struct pernet_operations ct_net_ops = {
1653 	.init = ct_init_net,
1654 	.exit_batch = ct_exit_net,
1655 	.id   = &act_ct_ops.net_id,
1656 	.size = sizeof(struct tc_ct_action_net),
1657 };
1658 
1659 static int __init ct_init_module(void)
1660 {
1661 	int err;
1662 
1663 	act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1664 	if (!act_ct_wq)
1665 		return -ENOMEM;
1666 
1667 	err = tcf_ct_flow_tables_init();
1668 	if (err)
1669 		goto err_tbl_init;
1670 
1671 	err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1672 	if (err)
1673 		goto err_register;
1674 
1675 	static_branch_inc(&tcf_frag_xmit_count);
1676 
1677 	return 0;
1678 
1679 err_register:
1680 	tcf_ct_flow_tables_uninit();
1681 err_tbl_init:
1682 	destroy_workqueue(act_ct_wq);
1683 	return err;
1684 }
1685 
1686 static void __exit ct_cleanup_module(void)
1687 {
1688 	static_branch_dec(&tcf_frag_xmit_count);
1689 	tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1690 	tcf_ct_flow_tables_uninit();
1691 	destroy_workqueue(act_ct_wq);
1692 }
1693 
1694 module_init(ct_init_module);
1695 module_exit(ct_cleanup_module);
1696 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1697 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1698 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1699 MODULE_DESCRIPTION("Connection tracking action");
1700 MODULE_LICENSE("GPL v2");
1701