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
28 #include <net/netfilter/nf_flow_table.h>
29 #include <net/netfilter/nf_conntrack.h>
30 #include <net/netfilter/nf_conntrack_core.h>
31 #include <net/netfilter/nf_conntrack_zones.h>
32 #include <net/netfilter/nf_conntrack_helper.h>
33 #include <net/netfilter/nf_conntrack_acct.h>
34 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
35 #include <uapi/linux/netfilter/nf_nat.h>
36
37 static struct workqueue_struct *act_ct_wq;
38 static struct rhashtable zones_ht;
39 static DEFINE_MUTEX(zones_mutex);
40
41 struct tcf_ct_flow_table {
42 struct rhash_head node; /* In zones tables */
43
44 struct rcu_work rwork;
45 struct nf_flowtable nf_ft;
46 refcount_t ref;
47 u16 zone;
48
49 bool dying;
50 };
51
52 static const struct rhashtable_params zones_params = {
53 .head_offset = offsetof(struct tcf_ct_flow_table, node),
54 .key_offset = offsetof(struct tcf_ct_flow_table, zone),
55 .key_len = sizeof_field(struct tcf_ct_flow_table, zone),
56 .automatic_shrinking = true,
57 };
58
59 static struct flow_action_entry *
tcf_ct_flow_table_flow_action_get_next(struct flow_action * flow_action)60 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action)
61 {
62 int i = flow_action->num_entries++;
63
64 return &flow_action->entries[i];
65 }
66
tcf_ct_add_mangle_action(struct flow_action * action,enum flow_action_mangle_base htype,u32 offset,u32 mask,u32 val)67 static void tcf_ct_add_mangle_action(struct flow_action *action,
68 enum flow_action_mangle_base htype,
69 u32 offset,
70 u32 mask,
71 u32 val)
72 {
73 struct flow_action_entry *entry;
74
75 entry = tcf_ct_flow_table_flow_action_get_next(action);
76 entry->id = FLOW_ACTION_MANGLE;
77 entry->mangle.htype = htype;
78 entry->mangle.mask = ~mask;
79 entry->mangle.offset = offset;
80 entry->mangle.val = val;
81 }
82
83 /* The following nat helper functions check if the inverted reverse tuple
84 * (target) is different then the current dir tuple - meaning nat for ports
85 * and/or ip is needed, and add the relevant mangle actions.
86 */
87 static void
tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple target,struct flow_action * action)88 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple,
89 struct nf_conntrack_tuple target,
90 struct flow_action *action)
91 {
92 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
93 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
94 offsetof(struct iphdr, saddr),
95 0xFFFFFFFF,
96 be32_to_cpu(target.src.u3.ip));
97 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
98 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
99 offsetof(struct iphdr, daddr),
100 0xFFFFFFFF,
101 be32_to_cpu(target.dst.u3.ip));
102 }
103
104 static void
tcf_ct_add_ipv6_addr_mangle_action(struct flow_action * action,union nf_inet_addr * addr,u32 offset)105 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action,
106 union nf_inet_addr *addr,
107 u32 offset)
108 {
109 int i;
110
111 for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++)
112 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
113 i * sizeof(u32) + offset,
114 0xFFFFFFFF, be32_to_cpu(addr->ip6[i]));
115 }
116
117 static void
tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple target,struct flow_action * action)118 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple,
119 struct nf_conntrack_tuple target,
120 struct flow_action *action)
121 {
122 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
123 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3,
124 offsetof(struct ipv6hdr,
125 saddr));
126 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
127 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3,
128 offsetof(struct ipv6hdr,
129 daddr));
130 }
131
132 static void
tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple target,struct flow_action * action)133 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple,
134 struct nf_conntrack_tuple target,
135 struct flow_action *action)
136 {
137 __be16 target_src = target.src.u.tcp.port;
138 __be16 target_dst = target.dst.u.tcp.port;
139
140 if (target_src != tuple->src.u.tcp.port)
141 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
142 offsetof(struct tcphdr, source),
143 0xFFFF, be16_to_cpu(target_src));
144 if (target_dst != tuple->dst.u.tcp.port)
145 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
146 offsetof(struct tcphdr, dest),
147 0xFFFF, be16_to_cpu(target_dst));
148 }
149
150 static void
tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple target,struct flow_action * action)151 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple,
152 struct nf_conntrack_tuple target,
153 struct flow_action *action)
154 {
155 __be16 target_src = target.src.u.udp.port;
156 __be16 target_dst = target.dst.u.udp.port;
157
158 if (target_src != tuple->src.u.udp.port)
159 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
160 offsetof(struct udphdr, source),
161 0xFFFF, be16_to_cpu(target_src));
162 if (target_dst != tuple->dst.u.udp.port)
163 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
164 offsetof(struct udphdr, dest),
165 0xFFFF, be16_to_cpu(target_dst));
166 }
167
tcf_ct_flow_table_add_action_meta(struct nf_conn * ct,enum ip_conntrack_dir dir,struct flow_action * action)168 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct,
169 enum ip_conntrack_dir dir,
170 struct flow_action *action)
171 {
172 struct nf_conn_labels *ct_labels;
173 struct flow_action_entry *entry;
174 enum ip_conntrack_info ctinfo;
175 u32 *act_ct_labels;
176
177 entry = tcf_ct_flow_table_flow_action_get_next(action);
178 entry->id = FLOW_ACTION_CT_METADATA;
179 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
180 entry->ct_metadata.mark = READ_ONCE(ct->mark);
181 #endif
182 ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
183 IP_CT_ESTABLISHED_REPLY;
184 /* aligns with the CT reference on the SKB nf_ct_set */
185 entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
186
187 act_ct_labels = entry->ct_metadata.labels;
188 ct_labels = nf_ct_labels_find(ct);
189 if (ct_labels)
190 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
191 else
192 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
193 }
194
tcf_ct_flow_table_add_action_nat(struct net * net,struct nf_conn * ct,enum ip_conntrack_dir dir,struct flow_action * action)195 static int tcf_ct_flow_table_add_action_nat(struct net *net,
196 struct nf_conn *ct,
197 enum ip_conntrack_dir dir,
198 struct flow_action *action)
199 {
200 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
201 struct nf_conntrack_tuple target;
202
203 if (!(ct->status & IPS_NAT_MASK))
204 return 0;
205
206 nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
207
208 switch (tuple->src.l3num) {
209 case NFPROTO_IPV4:
210 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
211 action);
212 break;
213 case NFPROTO_IPV6:
214 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
215 action);
216 break;
217 default:
218 return -EOPNOTSUPP;
219 }
220
221 switch (nf_ct_protonum(ct)) {
222 case IPPROTO_TCP:
223 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
224 break;
225 case IPPROTO_UDP:
226 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
227 break;
228 default:
229 return -EOPNOTSUPP;
230 }
231
232 return 0;
233 }
234
tcf_ct_flow_table_fill_actions(struct net * net,const struct flow_offload * flow,enum flow_offload_tuple_dir tdir,struct nf_flow_rule * flow_rule)235 static int tcf_ct_flow_table_fill_actions(struct net *net,
236 const struct flow_offload *flow,
237 enum flow_offload_tuple_dir tdir,
238 struct nf_flow_rule *flow_rule)
239 {
240 struct flow_action *action = &flow_rule->rule->action;
241 int num_entries = action->num_entries;
242 struct nf_conn *ct = flow->ct;
243 enum ip_conntrack_dir dir;
244 int i, err;
245
246 switch (tdir) {
247 case FLOW_OFFLOAD_DIR_ORIGINAL:
248 dir = IP_CT_DIR_ORIGINAL;
249 break;
250 case FLOW_OFFLOAD_DIR_REPLY:
251 dir = IP_CT_DIR_REPLY;
252 break;
253 default:
254 return -EOPNOTSUPP;
255 }
256
257 err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
258 if (err)
259 goto err_nat;
260
261 tcf_ct_flow_table_add_action_meta(ct, dir, action);
262 return 0;
263
264 err_nat:
265 /* Clear filled actions */
266 for (i = num_entries; i < action->num_entries; i++)
267 memset(&action->entries[i], 0, sizeof(action->entries[i]));
268 action->num_entries = num_entries;
269
270 return err;
271 }
272
273 static struct nf_flowtable_type flowtable_ct = {
274 .action = tcf_ct_flow_table_fill_actions,
275 .owner = THIS_MODULE,
276 };
277
tcf_ct_flow_table_get(struct tcf_ct_params * params)278 static int tcf_ct_flow_table_get(struct tcf_ct_params *params)
279 {
280 struct tcf_ct_flow_table *ct_ft;
281 int err = -ENOMEM;
282
283 mutex_lock(&zones_mutex);
284 ct_ft = rhashtable_lookup_fast(&zones_ht, ¶ms->zone, zones_params);
285 if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
286 goto out_unlock;
287
288 ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
289 if (!ct_ft)
290 goto err_alloc;
291 refcount_set(&ct_ft->ref, 1);
292
293 ct_ft->zone = params->zone;
294 err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
295 if (err)
296 goto err_insert;
297
298 ct_ft->nf_ft.type = &flowtable_ct;
299 ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD;
300 err = nf_flow_table_init(&ct_ft->nf_ft);
301 if (err)
302 goto err_init;
303
304 __module_get(THIS_MODULE);
305 out_unlock:
306 params->ct_ft = ct_ft;
307 params->nf_ft = &ct_ft->nf_ft;
308 mutex_unlock(&zones_mutex);
309
310 return 0;
311
312 err_init:
313 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
314 err_insert:
315 kfree(ct_ft);
316 err_alloc:
317 mutex_unlock(&zones_mutex);
318 return err;
319 }
320
tcf_ct_flow_table_cleanup_work(struct work_struct * work)321 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
322 {
323 struct flow_block_cb *block_cb, *tmp_cb;
324 struct tcf_ct_flow_table *ct_ft;
325 struct flow_block *block;
326
327 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
328 rwork);
329 nf_flow_table_free(&ct_ft->nf_ft);
330
331 /* Remove any remaining callbacks before cleanup */
332 block = &ct_ft->nf_ft.flow_block;
333 down_write(&ct_ft->nf_ft.flow_block_lock);
334 list_for_each_entry_safe(block_cb, tmp_cb, &block->cb_list, list) {
335 list_del(&block_cb->list);
336 flow_block_cb_free(block_cb);
337 }
338 up_write(&ct_ft->nf_ft.flow_block_lock);
339 kfree(ct_ft);
340
341 module_put(THIS_MODULE);
342 }
343
tcf_ct_flow_table_put(struct tcf_ct_params * params)344 static void tcf_ct_flow_table_put(struct tcf_ct_params *params)
345 {
346 struct tcf_ct_flow_table *ct_ft = params->ct_ft;
347
348 if (refcount_dec_and_test(¶ms->ct_ft->ref)) {
349 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
350 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
351 queue_rcu_work(act_ct_wq, &ct_ft->rwork);
352 }
353 }
354
tcf_ct_flow_table_add(struct tcf_ct_flow_table * ct_ft,struct nf_conn * ct,bool tcp)355 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
356 struct nf_conn *ct,
357 bool tcp)
358 {
359 struct flow_offload *entry;
360 int err;
361
362 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
363 return;
364
365 entry = flow_offload_alloc(ct);
366 if (!entry) {
367 WARN_ON_ONCE(1);
368 goto err_alloc;
369 }
370
371 if (tcp) {
372 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
373 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
374 }
375
376 err = flow_offload_add(&ct_ft->nf_ft, entry);
377 if (err)
378 goto err_add;
379
380 return;
381
382 err_add:
383 flow_offload_free(entry);
384 err_alloc:
385 clear_bit(IPS_OFFLOAD_BIT, &ct->status);
386 }
387
tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table * ct_ft,struct nf_conn * ct,enum ip_conntrack_info ctinfo)388 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
389 struct nf_conn *ct,
390 enum ip_conntrack_info ctinfo)
391 {
392 bool tcp = false;
393
394 if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
395 return;
396
397 switch (nf_ct_protonum(ct)) {
398 case IPPROTO_TCP:
399 tcp = true;
400 if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
401 return;
402 break;
403 case IPPROTO_UDP:
404 break;
405 default:
406 return;
407 }
408
409 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
410 ct->status & IPS_SEQ_ADJUST)
411 return;
412
413 tcf_ct_flow_table_add(ct_ft, ct, tcp);
414 }
415
416 static bool
tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff * skb,struct flow_offload_tuple * tuple,struct tcphdr ** tcph)417 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
418 struct flow_offload_tuple *tuple,
419 struct tcphdr **tcph)
420 {
421 struct flow_ports *ports;
422 unsigned int thoff;
423 struct iphdr *iph;
424
425 if (!pskb_network_may_pull(skb, sizeof(*iph)))
426 return false;
427
428 iph = ip_hdr(skb);
429 thoff = iph->ihl * 4;
430
431 if (ip_is_fragment(iph) ||
432 unlikely(thoff != sizeof(struct iphdr)))
433 return false;
434
435 if (iph->protocol != IPPROTO_TCP &&
436 iph->protocol != IPPROTO_UDP)
437 return false;
438
439 if (iph->ttl <= 1)
440 return false;
441
442 if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ?
443 thoff + sizeof(struct tcphdr) :
444 thoff + sizeof(*ports)))
445 return false;
446
447 iph = ip_hdr(skb);
448 if (iph->protocol == IPPROTO_TCP)
449 *tcph = (void *)(skb_network_header(skb) + thoff);
450
451 ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
452 tuple->src_v4.s_addr = iph->saddr;
453 tuple->dst_v4.s_addr = iph->daddr;
454 tuple->src_port = ports->source;
455 tuple->dst_port = ports->dest;
456 tuple->l3proto = AF_INET;
457 tuple->l4proto = iph->protocol;
458
459 return true;
460 }
461
462 static bool
tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff * skb,struct flow_offload_tuple * tuple,struct tcphdr ** tcph)463 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
464 struct flow_offload_tuple *tuple,
465 struct tcphdr **tcph)
466 {
467 struct flow_ports *ports;
468 struct ipv6hdr *ip6h;
469 unsigned int thoff;
470
471 if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
472 return false;
473
474 ip6h = ipv6_hdr(skb);
475
476 if (ip6h->nexthdr != IPPROTO_TCP &&
477 ip6h->nexthdr != IPPROTO_UDP)
478 return false;
479
480 if (ip6h->hop_limit <= 1)
481 return false;
482
483 thoff = sizeof(*ip6h);
484 if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ?
485 thoff + sizeof(struct tcphdr) :
486 thoff + sizeof(*ports)))
487 return false;
488
489 ip6h = ipv6_hdr(skb);
490 if (ip6h->nexthdr == IPPROTO_TCP)
491 *tcph = (void *)(skb_network_header(skb) + thoff);
492
493 ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
494 tuple->src_v6 = ip6h->saddr;
495 tuple->dst_v6 = ip6h->daddr;
496 tuple->src_port = ports->source;
497 tuple->dst_port = ports->dest;
498 tuple->l3proto = AF_INET6;
499 tuple->l4proto = ip6h->nexthdr;
500
501 return true;
502 }
503
tcf_ct_flow_table_lookup(struct tcf_ct_params * p,struct sk_buff * skb,u8 family)504 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
505 struct sk_buff *skb,
506 u8 family)
507 {
508 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
509 struct flow_offload_tuple_rhash *tuplehash;
510 struct flow_offload_tuple tuple = {};
511 enum ip_conntrack_info ctinfo;
512 struct tcphdr *tcph = NULL;
513 struct flow_offload *flow;
514 struct nf_conn *ct;
515 u8 dir;
516
517 switch (family) {
518 case NFPROTO_IPV4:
519 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
520 return false;
521 break;
522 case NFPROTO_IPV6:
523 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
524 return false;
525 break;
526 default:
527 return false;
528 }
529
530 tuplehash = flow_offload_lookup(nf_ft, &tuple);
531 if (!tuplehash)
532 return false;
533
534 dir = tuplehash->tuple.dir;
535 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
536 ct = flow->ct;
537
538 if (tcph && (unlikely(tcph->fin || tcph->rst))) {
539 flow_offload_teardown(flow);
540 return false;
541 }
542
543 ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
544 IP_CT_ESTABLISHED_REPLY;
545
546 flow_offload_refresh(nf_ft, flow);
547 nf_conntrack_get(&ct->ct_general);
548 nf_ct_set(skb, ct, ctinfo);
549 nf_ct_acct_update(ct, dir, skb->len);
550
551 return true;
552 }
553
tcf_ct_flow_tables_init(void)554 static int tcf_ct_flow_tables_init(void)
555 {
556 return rhashtable_init(&zones_ht, &zones_params);
557 }
558
tcf_ct_flow_tables_uninit(void)559 static void tcf_ct_flow_tables_uninit(void)
560 {
561 rhashtable_destroy(&zones_ht);
562 }
563
564 static struct tc_action_ops act_ct_ops;
565 static unsigned int ct_net_id;
566
567 struct tc_ct_action_net {
568 struct tc_action_net tn; /* Must be first */
569 bool labels;
570 };
571
572 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
tcf_ct_skb_nfct_cached(struct net * net,struct sk_buff * skb,u16 zone_id,bool force)573 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
574 u16 zone_id, bool force)
575 {
576 enum ip_conntrack_info ctinfo;
577 struct nf_conn *ct;
578
579 ct = nf_ct_get(skb, &ctinfo);
580 if (!ct)
581 return false;
582 if (!net_eq(net, read_pnet(&ct->ct_net)))
583 return false;
584 if (nf_ct_zone(ct)->id != zone_id)
585 return false;
586
587 /* Force conntrack entry direction. */
588 if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
589 if (nf_ct_is_confirmed(ct))
590 nf_ct_kill(ct);
591
592 nf_conntrack_put(&ct->ct_general);
593 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
594
595 return false;
596 }
597
598 return true;
599 }
600
601 /* Trim the skb to the length specified by the IP/IPv6 header,
602 * removing any trailing lower-layer padding. This prepares the skb
603 * for higher-layer processing that assumes skb->len excludes padding
604 * (such as nf_ip_checksum). The caller needs to pull the skb to the
605 * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
606 */
tcf_ct_skb_network_trim(struct sk_buff * skb,int family)607 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
608 {
609 unsigned int len;
610 int err;
611
612 switch (family) {
613 case NFPROTO_IPV4:
614 len = ntohs(ip_hdr(skb)->tot_len);
615 break;
616 case NFPROTO_IPV6:
617 len = sizeof(struct ipv6hdr)
618 + ntohs(ipv6_hdr(skb)->payload_len);
619 break;
620 default:
621 len = skb->len;
622 }
623
624 err = pskb_trim_rcsum(skb, len);
625
626 return err;
627 }
628
tcf_ct_skb_nf_family(struct sk_buff * skb)629 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
630 {
631 u8 family = NFPROTO_UNSPEC;
632
633 switch (skb_protocol(skb, true)) {
634 case htons(ETH_P_IP):
635 family = NFPROTO_IPV4;
636 break;
637 case htons(ETH_P_IPV6):
638 family = NFPROTO_IPV6;
639 break;
640 default:
641 break;
642 }
643
644 return family;
645 }
646
tcf_ct_ipv4_is_fragment(struct sk_buff * skb,bool * frag)647 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
648 {
649 unsigned int len;
650
651 len = skb_network_offset(skb) + sizeof(struct iphdr);
652 if (unlikely(skb->len < len))
653 return -EINVAL;
654 if (unlikely(!pskb_may_pull(skb, len)))
655 return -ENOMEM;
656
657 *frag = ip_is_fragment(ip_hdr(skb));
658 return 0;
659 }
660
tcf_ct_ipv6_is_fragment(struct sk_buff * skb,bool * frag)661 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
662 {
663 unsigned int flags = 0, len, payload_ofs = 0;
664 unsigned short frag_off;
665 int nexthdr;
666
667 len = skb_network_offset(skb) + sizeof(struct ipv6hdr);
668 if (unlikely(skb->len < len))
669 return -EINVAL;
670 if (unlikely(!pskb_may_pull(skb, len)))
671 return -ENOMEM;
672
673 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
674 if (unlikely(nexthdr < 0))
675 return -EPROTO;
676
677 *frag = flags & IP6_FH_F_FRAG;
678 return 0;
679 }
680
tcf_ct_handle_fragments(struct net * net,struct sk_buff * skb,u8 family,u16 zone,bool * defrag)681 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
682 u8 family, u16 zone, bool *defrag)
683 {
684 enum ip_conntrack_info ctinfo;
685 struct qdisc_skb_cb cb;
686 struct nf_conn *ct;
687 int err = 0;
688 bool frag;
689
690 /* Previously seen (loopback)? Ignore. */
691 ct = nf_ct_get(skb, &ctinfo);
692 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
693 return 0;
694
695 if (family == NFPROTO_IPV4)
696 err = tcf_ct_ipv4_is_fragment(skb, &frag);
697 else
698 err = tcf_ct_ipv6_is_fragment(skb, &frag);
699 if (err || !frag)
700 return err;
701
702 skb_get(skb);
703 cb = *qdisc_skb_cb(skb);
704
705 if (family == NFPROTO_IPV4) {
706 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
707
708 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
709 local_bh_disable();
710 err = ip_defrag(net, skb, user);
711 local_bh_enable();
712 if (err && err != -EINPROGRESS)
713 return err;
714
715 if (!err) {
716 *defrag = true;
717 cb.mru = IPCB(skb)->frag_max_size;
718 }
719 } else { /* NFPROTO_IPV6 */
720 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
721 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
722
723 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
724 err = nf_ct_frag6_gather(net, skb, user);
725 if (err && err != -EINPROGRESS)
726 goto out_free;
727
728 if (!err) {
729 *defrag = true;
730 cb.mru = IP6CB(skb)->frag_max_size;
731 }
732 #else
733 err = -EOPNOTSUPP;
734 goto out_free;
735 #endif
736 }
737
738 *qdisc_skb_cb(skb) = cb;
739 skb_clear_hash(skb);
740 skb->ignore_df = 1;
741 return err;
742
743 out_free:
744 kfree_skb(skb);
745 return err;
746 }
747
tcf_ct_params_free(struct rcu_head * head)748 static void tcf_ct_params_free(struct rcu_head *head)
749 {
750 struct tcf_ct_params *params = container_of(head,
751 struct tcf_ct_params, rcu);
752
753 tcf_ct_flow_table_put(params);
754
755 if (params->tmpl)
756 nf_conntrack_put(¶ms->tmpl->ct_general);
757 kfree(params);
758 }
759
760 #if IS_ENABLED(CONFIG_NF_NAT)
761 /* Modelled after nf_nat_ipv[46]_fn().
762 * range is only used for new, uninitialized NAT state.
763 * Returns either NF_ACCEPT or NF_DROP.
764 */
ct_nat_execute(struct sk_buff * skb,struct nf_conn * ct,enum ip_conntrack_info ctinfo,const struct nf_nat_range2 * range,enum nf_nat_manip_type maniptype)765 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
766 enum ip_conntrack_info ctinfo,
767 const struct nf_nat_range2 *range,
768 enum nf_nat_manip_type maniptype)
769 {
770 __be16 proto = skb_protocol(skb, true);
771 int hooknum, err = NF_ACCEPT;
772
773 /* See HOOK2MANIP(). */
774 if (maniptype == NF_NAT_MANIP_SRC)
775 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
776 else
777 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
778
779 switch (ctinfo) {
780 case IP_CT_RELATED:
781 case IP_CT_RELATED_REPLY:
782 if (proto == htons(ETH_P_IP) &&
783 ip_hdr(skb)->protocol == IPPROTO_ICMP) {
784 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
785 hooknum))
786 err = NF_DROP;
787 goto out;
788 } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) {
789 __be16 frag_off;
790 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
791 int hdrlen = ipv6_skip_exthdr(skb,
792 sizeof(struct ipv6hdr),
793 &nexthdr, &frag_off);
794
795 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
796 if (!nf_nat_icmpv6_reply_translation(skb, ct,
797 ctinfo,
798 hooknum,
799 hdrlen))
800 err = NF_DROP;
801 goto out;
802 }
803 }
804 /* Non-ICMP, fall thru to initialize if needed. */
805 fallthrough;
806 case IP_CT_NEW:
807 /* Seen it before? This can happen for loopback, retrans,
808 * or local packets.
809 */
810 if (!nf_nat_initialized(ct, maniptype)) {
811 /* Initialize according to the NAT action. */
812 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
813 /* Action is set up to establish a new
814 * mapping.
815 */
816 ? nf_nat_setup_info(ct, range, maniptype)
817 : nf_nat_alloc_null_binding(ct, hooknum);
818 if (err != NF_ACCEPT)
819 goto out;
820 }
821 break;
822
823 case IP_CT_ESTABLISHED:
824 case IP_CT_ESTABLISHED_REPLY:
825 break;
826
827 default:
828 err = NF_DROP;
829 goto out;
830 }
831
832 err = nf_nat_packet(ct, ctinfo, hooknum, skb);
833 out:
834 return err;
835 }
836 #endif /* CONFIG_NF_NAT */
837
tcf_ct_act_set_mark(struct nf_conn * ct,u32 mark,u32 mask)838 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
839 {
840 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
841 u32 new_mark;
842
843 if (!mask)
844 return;
845
846 new_mark = mark | (READ_ONCE(ct->mark) & ~(mask));
847 if (READ_ONCE(ct->mark) != new_mark) {
848 WRITE_ONCE(ct->mark, new_mark);
849 if (nf_ct_is_confirmed(ct))
850 nf_conntrack_event_cache(IPCT_MARK, ct);
851 }
852 #endif
853 }
854
tcf_ct_act_set_labels(struct nf_conn * ct,u32 * labels,u32 * labels_m)855 static void tcf_ct_act_set_labels(struct nf_conn *ct,
856 u32 *labels,
857 u32 *labels_m)
858 {
859 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
860 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
861
862 if (!memchr_inv(labels_m, 0, labels_sz))
863 return;
864
865 nf_connlabels_replace(ct, labels, labels_m, 4);
866 #endif
867 }
868
tcf_ct_act_nat(struct sk_buff * skb,struct nf_conn * ct,enum ip_conntrack_info ctinfo,int ct_action,struct nf_nat_range2 * range,bool commit)869 static int tcf_ct_act_nat(struct sk_buff *skb,
870 struct nf_conn *ct,
871 enum ip_conntrack_info ctinfo,
872 int ct_action,
873 struct nf_nat_range2 *range,
874 bool commit)
875 {
876 #if IS_ENABLED(CONFIG_NF_NAT)
877 int err;
878 enum nf_nat_manip_type maniptype;
879
880 if (!(ct_action & TCA_CT_ACT_NAT))
881 return NF_ACCEPT;
882
883 /* Add NAT extension if not confirmed yet. */
884 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
885 return NF_DROP; /* Can't NAT. */
886
887 if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) &&
888 (ctinfo != IP_CT_RELATED || commit)) {
889 /* NAT an established or related connection like before. */
890 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
891 /* This is the REPLY direction for a connection
892 * for which NAT was applied in the forward
893 * direction. Do the reverse NAT.
894 */
895 maniptype = ct->status & IPS_SRC_NAT
896 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
897 else
898 maniptype = ct->status & IPS_SRC_NAT
899 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
900 } else if (ct_action & TCA_CT_ACT_NAT_SRC) {
901 maniptype = NF_NAT_MANIP_SRC;
902 } else if (ct_action & TCA_CT_ACT_NAT_DST) {
903 maniptype = NF_NAT_MANIP_DST;
904 } else {
905 return NF_ACCEPT;
906 }
907
908 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
909 if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) {
910 if (ct->status & IPS_SRC_NAT) {
911 if (maniptype == NF_NAT_MANIP_SRC)
912 maniptype = NF_NAT_MANIP_DST;
913 else
914 maniptype = NF_NAT_MANIP_SRC;
915
916 err = ct_nat_execute(skb, ct, ctinfo, range,
917 maniptype);
918 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) {
919 err = ct_nat_execute(skb, ct, ctinfo, NULL,
920 NF_NAT_MANIP_SRC);
921 }
922 }
923 return err;
924 #else
925 return NF_ACCEPT;
926 #endif
927 }
928
tcf_ct_act(struct sk_buff * skb,const struct tc_action * a,struct tcf_result * res)929 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
930 struct tcf_result *res)
931 {
932 struct net *net = dev_net(skb->dev);
933 bool cached, commit, clear, force;
934 enum ip_conntrack_info ctinfo;
935 struct tcf_ct *c = to_ct(a);
936 struct nf_conn *tmpl = NULL;
937 struct nf_hook_state state;
938 int nh_ofs, err, retval;
939 struct tcf_ct_params *p;
940 bool skip_add = false;
941 bool defrag = false;
942 struct nf_conn *ct;
943 u8 family;
944
945 p = rcu_dereference_bh(c->params);
946
947 retval = READ_ONCE(c->tcf_action);
948 commit = p->ct_action & TCA_CT_ACT_COMMIT;
949 clear = p->ct_action & TCA_CT_ACT_CLEAR;
950 force = p->ct_action & TCA_CT_ACT_FORCE;
951 tmpl = p->tmpl;
952
953 tcf_lastuse_update(&c->tcf_tm);
954
955 if (clear) {
956 ct = nf_ct_get(skb, &ctinfo);
957 if (ct) {
958 nf_conntrack_put(&ct->ct_general);
959 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
960 }
961
962 goto out;
963 }
964
965 family = tcf_ct_skb_nf_family(skb);
966 if (family == NFPROTO_UNSPEC)
967 goto drop;
968
969 /* The conntrack module expects to be working at L3.
970 * We also try to pull the IPv4/6 header to linear area
971 */
972 nh_ofs = skb_network_offset(skb);
973 skb_pull_rcsum(skb, nh_ofs);
974 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
975 if (err == -EINPROGRESS) {
976 retval = TC_ACT_STOLEN;
977 goto out;
978 }
979 if (err)
980 goto drop;
981
982 err = tcf_ct_skb_network_trim(skb, family);
983 if (err)
984 goto drop;
985
986 /* If we are recirculating packets to match on ct fields and
987 * committing with a separate ct action, then we don't need to
988 * actually run the packet through conntrack twice unless it's for a
989 * different zone.
990 */
991 cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);
992 if (!cached) {
993 if (tcf_ct_flow_table_lookup(p, skb, family)) {
994 skip_add = true;
995 goto do_nat;
996 }
997
998 /* Associate skb with specified zone. */
999 if (tmpl) {
1000 ct = nf_ct_get(skb, &ctinfo);
1001 if (skb_nfct(skb))
1002 nf_conntrack_put(skb_nfct(skb));
1003 nf_conntrack_get(&tmpl->ct_general);
1004 nf_ct_set(skb, tmpl, IP_CT_NEW);
1005 }
1006
1007 state.hook = NF_INET_PRE_ROUTING;
1008 state.net = net;
1009 state.pf = family;
1010 err = nf_conntrack_in(skb, &state);
1011 if (err != NF_ACCEPT)
1012 goto out_push;
1013 }
1014
1015 do_nat:
1016 ct = nf_ct_get(skb, &ctinfo);
1017 if (!ct)
1018 goto out_push;
1019 nf_ct_deliver_cached_events(ct);
1020
1021 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1022 if (err != NF_ACCEPT)
1023 goto drop;
1024
1025 if (commit) {
1026 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1027 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1028
1029 /* This will take care of sending queued events
1030 * even if the connection is already confirmed.
1031 */
1032 if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1033 goto drop;
1034 }
1035
1036 if (!skip_add)
1037 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1038
1039 out_push:
1040 skb_push_rcsum(skb, nh_ofs);
1041
1042 out:
1043 tcf_action_update_bstats(&c->common, skb);
1044 if (defrag)
1045 qdisc_skb_cb(skb)->pkt_len = skb->len;
1046 return retval;
1047
1048 drop:
1049 tcf_action_inc_drop_qstats(&c->common);
1050 return TC_ACT_SHOT;
1051 }
1052
1053 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1054 [TCA_CT_ACTION] = { .type = NLA_U16 },
1055 [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)),
1056 [TCA_CT_ZONE] = { .type = NLA_U16 },
1057 [TCA_CT_MARK] = { .type = NLA_U32 },
1058 [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1059 [TCA_CT_LABELS] = { .type = NLA_BINARY,
1060 .len = 128 / BITS_PER_BYTE },
1061 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1062 .len = 128 / BITS_PER_BYTE },
1063 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1064 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1065 [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1066 [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1067 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1068 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1069 };
1070
tcf_ct_fill_params_nat(struct tcf_ct_params * p,struct tc_ct * parm,struct nlattr ** tb,struct netlink_ext_ack * extack)1071 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1072 struct tc_ct *parm,
1073 struct nlattr **tb,
1074 struct netlink_ext_ack *extack)
1075 {
1076 struct nf_nat_range2 *range;
1077
1078 if (!(p->ct_action & TCA_CT_ACT_NAT))
1079 return 0;
1080
1081 if (!IS_ENABLED(CONFIG_NF_NAT)) {
1082 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1083 return -EOPNOTSUPP;
1084 }
1085
1086 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1087 return 0;
1088
1089 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1090 (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1091 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1092 return -EOPNOTSUPP;
1093 }
1094
1095 range = &p->range;
1096 if (tb[TCA_CT_NAT_IPV4_MIN]) {
1097 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1098
1099 p->ipv4_range = true;
1100 range->flags |= NF_NAT_RANGE_MAP_IPS;
1101 range->min_addr.ip =
1102 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1103
1104 range->max_addr.ip = max_attr ?
1105 nla_get_in_addr(max_attr) :
1106 range->min_addr.ip;
1107 } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1108 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1109
1110 p->ipv4_range = false;
1111 range->flags |= NF_NAT_RANGE_MAP_IPS;
1112 range->min_addr.in6 =
1113 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1114
1115 range->max_addr.in6 = max_attr ?
1116 nla_get_in6_addr(max_attr) :
1117 range->min_addr.in6;
1118 }
1119
1120 if (tb[TCA_CT_NAT_PORT_MIN]) {
1121 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1122 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1123
1124 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1125 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1126 range->min_proto.all;
1127 }
1128
1129 return 0;
1130 }
1131
tcf_ct_set_key_val(struct nlattr ** tb,void * val,int val_type,void * mask,int mask_type,int len)1132 static void tcf_ct_set_key_val(struct nlattr **tb,
1133 void *val, int val_type,
1134 void *mask, int mask_type,
1135 int len)
1136 {
1137 if (!tb[val_type])
1138 return;
1139 nla_memcpy(val, tb[val_type], len);
1140
1141 if (!mask)
1142 return;
1143
1144 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1145 memset(mask, 0xff, len);
1146 else
1147 nla_memcpy(mask, tb[mask_type], len);
1148 }
1149
tcf_ct_fill_params(struct net * net,struct tcf_ct_params * p,struct tc_ct * parm,struct nlattr ** tb,struct netlink_ext_ack * extack)1150 static int tcf_ct_fill_params(struct net *net,
1151 struct tcf_ct_params *p,
1152 struct tc_ct *parm,
1153 struct nlattr **tb,
1154 struct netlink_ext_ack *extack)
1155 {
1156 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1157 struct nf_conntrack_zone zone;
1158 struct nf_conn *tmpl;
1159 int err;
1160
1161 p->zone = NF_CT_DEFAULT_ZONE_ID;
1162
1163 tcf_ct_set_key_val(tb,
1164 &p->ct_action, TCA_CT_ACTION,
1165 NULL, TCA_CT_UNSPEC,
1166 sizeof(p->ct_action));
1167
1168 if (p->ct_action & TCA_CT_ACT_CLEAR)
1169 return 0;
1170
1171 err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1172 if (err)
1173 return err;
1174
1175 if (tb[TCA_CT_MARK]) {
1176 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1177 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1178 return -EOPNOTSUPP;
1179 }
1180 tcf_ct_set_key_val(tb,
1181 &p->mark, TCA_CT_MARK,
1182 &p->mark_mask, TCA_CT_MARK_MASK,
1183 sizeof(p->mark));
1184 }
1185
1186 if (tb[TCA_CT_LABELS]) {
1187 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1188 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1189 return -EOPNOTSUPP;
1190 }
1191
1192 if (!tn->labels) {
1193 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1194 return -EOPNOTSUPP;
1195 }
1196 tcf_ct_set_key_val(tb,
1197 p->labels, TCA_CT_LABELS,
1198 p->labels_mask, TCA_CT_LABELS_MASK,
1199 sizeof(p->labels));
1200 }
1201
1202 if (tb[TCA_CT_ZONE]) {
1203 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1204 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1205 return -EOPNOTSUPP;
1206 }
1207
1208 tcf_ct_set_key_val(tb,
1209 &p->zone, TCA_CT_ZONE,
1210 NULL, TCA_CT_UNSPEC,
1211 sizeof(p->zone));
1212 }
1213
1214 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1215 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1216 if (!tmpl) {
1217 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1218 return -ENOMEM;
1219 }
1220 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1221 nf_conntrack_get(&tmpl->ct_general);
1222 p->tmpl = tmpl;
1223
1224 return 0;
1225 }
1226
tcf_ct_init(struct net * net,struct nlattr * nla,struct nlattr * est,struct tc_action ** a,int replace,int bind,bool rtnl_held,struct tcf_proto * tp,u32 flags,struct netlink_ext_ack * extack)1227 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1228 struct nlattr *est, struct tc_action **a,
1229 int replace, int bind, bool rtnl_held,
1230 struct tcf_proto *tp, u32 flags,
1231 struct netlink_ext_ack *extack)
1232 {
1233 struct tc_action_net *tn = net_generic(net, ct_net_id);
1234 struct tcf_ct_params *params = NULL;
1235 struct nlattr *tb[TCA_CT_MAX + 1];
1236 struct tcf_chain *goto_ch = NULL;
1237 struct tc_ct *parm;
1238 struct tcf_ct *c;
1239 int err, res = 0;
1240 u32 index;
1241
1242 if (!nla) {
1243 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1244 return -EINVAL;
1245 }
1246
1247 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1248 if (err < 0)
1249 return err;
1250
1251 if (!tb[TCA_CT_PARMS]) {
1252 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1253 return -EINVAL;
1254 }
1255 parm = nla_data(tb[TCA_CT_PARMS]);
1256 index = parm->index;
1257 err = tcf_idr_check_alloc(tn, &index, a, bind);
1258 if (err < 0)
1259 return err;
1260
1261 if (!err) {
1262 err = tcf_idr_create_from_flags(tn, index, est, a,
1263 &act_ct_ops, bind, flags);
1264 if (err) {
1265 tcf_idr_cleanup(tn, index);
1266 return err;
1267 }
1268 res = ACT_P_CREATED;
1269 } else {
1270 if (bind)
1271 return 0;
1272
1273 if (!replace) {
1274 tcf_idr_release(*a, bind);
1275 return -EEXIST;
1276 }
1277 }
1278 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1279 if (err < 0)
1280 goto cleanup;
1281
1282 c = to_ct(*a);
1283
1284 params = kzalloc(sizeof(*params), GFP_KERNEL);
1285 if (unlikely(!params)) {
1286 err = -ENOMEM;
1287 goto cleanup;
1288 }
1289
1290 err = tcf_ct_fill_params(net, params, parm, tb, extack);
1291 if (err)
1292 goto cleanup;
1293
1294 err = tcf_ct_flow_table_get(params);
1295 if (err)
1296 goto cleanup_params;
1297
1298 spin_lock_bh(&c->tcf_lock);
1299 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1300 params = rcu_replace_pointer(c->params, params,
1301 lockdep_is_held(&c->tcf_lock));
1302 spin_unlock_bh(&c->tcf_lock);
1303
1304 if (goto_ch)
1305 tcf_chain_put_by_act(goto_ch);
1306 if (params)
1307 call_rcu(¶ms->rcu, tcf_ct_params_free);
1308
1309 return res;
1310
1311 cleanup_params:
1312 if (params->tmpl)
1313 nf_ct_put(params->tmpl);
1314 cleanup:
1315 if (goto_ch)
1316 tcf_chain_put_by_act(goto_ch);
1317 kfree(params);
1318 tcf_idr_release(*a, bind);
1319 return err;
1320 }
1321
tcf_ct_cleanup(struct tc_action * a)1322 static void tcf_ct_cleanup(struct tc_action *a)
1323 {
1324 struct tcf_ct_params *params;
1325 struct tcf_ct *c = to_ct(a);
1326
1327 params = rcu_dereference_protected(c->params, 1);
1328 if (params)
1329 call_rcu(¶ms->rcu, tcf_ct_params_free);
1330 }
1331
tcf_ct_dump_key_val(struct sk_buff * skb,void * val,int val_type,void * mask,int mask_type,int len)1332 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1333 void *val, int val_type,
1334 void *mask, int mask_type,
1335 int len)
1336 {
1337 int err;
1338
1339 if (mask && !memchr_inv(mask, 0, len))
1340 return 0;
1341
1342 err = nla_put(skb, val_type, len, val);
1343 if (err)
1344 return err;
1345
1346 if (mask_type != TCA_CT_UNSPEC) {
1347 err = nla_put(skb, mask_type, len, mask);
1348 if (err)
1349 return err;
1350 }
1351
1352 return 0;
1353 }
1354
tcf_ct_dump_nat(struct sk_buff * skb,struct tcf_ct_params * p)1355 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1356 {
1357 struct nf_nat_range2 *range = &p->range;
1358
1359 if (!(p->ct_action & TCA_CT_ACT_NAT))
1360 return 0;
1361
1362 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1363 return 0;
1364
1365 if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1366 if (p->ipv4_range) {
1367 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1368 range->min_addr.ip))
1369 return -1;
1370 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1371 range->max_addr.ip))
1372 return -1;
1373 } else {
1374 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1375 &range->min_addr.in6))
1376 return -1;
1377 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1378 &range->max_addr.in6))
1379 return -1;
1380 }
1381 }
1382
1383 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1384 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1385 range->min_proto.all))
1386 return -1;
1387 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1388 range->max_proto.all))
1389 return -1;
1390 }
1391
1392 return 0;
1393 }
1394
tcf_ct_dump(struct sk_buff * skb,struct tc_action * a,int bind,int ref)1395 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1396 int bind, int ref)
1397 {
1398 unsigned char *b = skb_tail_pointer(skb);
1399 struct tcf_ct *c = to_ct(a);
1400 struct tcf_ct_params *p;
1401
1402 struct tc_ct opt = {
1403 .index = c->tcf_index,
1404 .refcnt = refcount_read(&c->tcf_refcnt) - ref,
1405 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1406 };
1407 struct tcf_t t;
1408
1409 spin_lock_bh(&c->tcf_lock);
1410 p = rcu_dereference_protected(c->params,
1411 lockdep_is_held(&c->tcf_lock));
1412 opt.action = c->tcf_action;
1413
1414 if (tcf_ct_dump_key_val(skb,
1415 &p->ct_action, TCA_CT_ACTION,
1416 NULL, TCA_CT_UNSPEC,
1417 sizeof(p->ct_action)))
1418 goto nla_put_failure;
1419
1420 if (p->ct_action & TCA_CT_ACT_CLEAR)
1421 goto skip_dump;
1422
1423 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1424 tcf_ct_dump_key_val(skb,
1425 &p->mark, TCA_CT_MARK,
1426 &p->mark_mask, TCA_CT_MARK_MASK,
1427 sizeof(p->mark)))
1428 goto nla_put_failure;
1429
1430 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1431 tcf_ct_dump_key_val(skb,
1432 p->labels, TCA_CT_LABELS,
1433 p->labels_mask, TCA_CT_LABELS_MASK,
1434 sizeof(p->labels)))
1435 goto nla_put_failure;
1436
1437 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1438 tcf_ct_dump_key_val(skb,
1439 &p->zone, TCA_CT_ZONE,
1440 NULL, TCA_CT_UNSPEC,
1441 sizeof(p->zone)))
1442 goto nla_put_failure;
1443
1444 if (tcf_ct_dump_nat(skb, p))
1445 goto nla_put_failure;
1446
1447 skip_dump:
1448 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1449 goto nla_put_failure;
1450
1451 tcf_tm_dump(&t, &c->tcf_tm);
1452 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1453 goto nla_put_failure;
1454 spin_unlock_bh(&c->tcf_lock);
1455
1456 return skb->len;
1457 nla_put_failure:
1458 spin_unlock_bh(&c->tcf_lock);
1459 nlmsg_trim(skb, b);
1460 return -1;
1461 }
1462
tcf_ct_walker(struct net * net,struct sk_buff * skb,struct netlink_callback * cb,int type,const struct tc_action_ops * ops,struct netlink_ext_ack * extack)1463 static int tcf_ct_walker(struct net *net, struct sk_buff *skb,
1464 struct netlink_callback *cb, int type,
1465 const struct tc_action_ops *ops,
1466 struct netlink_ext_ack *extack)
1467 {
1468 struct tc_action_net *tn = net_generic(net, ct_net_id);
1469
1470 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
1471 }
1472
tcf_ct_search(struct net * net,struct tc_action ** a,u32 index)1473 static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index)
1474 {
1475 struct tc_action_net *tn = net_generic(net, ct_net_id);
1476
1477 return tcf_idr_search(tn, a, index);
1478 }
1479
tcf_stats_update(struct tc_action * a,u64 bytes,u64 packets,u64 drops,u64 lastuse,bool hw)1480 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1481 u64 drops, u64 lastuse, bool hw)
1482 {
1483 struct tcf_ct *c = to_ct(a);
1484
1485 tcf_action_update_stats(a, bytes, packets, drops, hw);
1486 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1487 }
1488
1489 static struct tc_action_ops act_ct_ops = {
1490 .kind = "ct",
1491 .id = TCA_ID_CT,
1492 .owner = THIS_MODULE,
1493 .act = tcf_ct_act,
1494 .dump = tcf_ct_dump,
1495 .init = tcf_ct_init,
1496 .cleanup = tcf_ct_cleanup,
1497 .walk = tcf_ct_walker,
1498 .lookup = tcf_ct_search,
1499 .stats_update = tcf_stats_update,
1500 .size = sizeof(struct tcf_ct),
1501 };
1502
ct_init_net(struct net * net)1503 static __net_init int ct_init_net(struct net *net)
1504 {
1505 unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1506 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1507
1508 if (nf_connlabels_get(net, n_bits - 1)) {
1509 tn->labels = false;
1510 pr_err("act_ct: Failed to set connlabels length");
1511 } else {
1512 tn->labels = true;
1513 }
1514
1515 return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1516 }
1517
ct_exit_net(struct list_head * net_list)1518 static void __net_exit ct_exit_net(struct list_head *net_list)
1519 {
1520 struct net *net;
1521
1522 rtnl_lock();
1523 list_for_each_entry(net, net_list, exit_list) {
1524 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1525
1526 if (tn->labels)
1527 nf_connlabels_put(net);
1528 }
1529 rtnl_unlock();
1530
1531 tc_action_net_exit(net_list, ct_net_id);
1532 }
1533
1534 static struct pernet_operations ct_net_ops = {
1535 .init = ct_init_net,
1536 .exit_batch = ct_exit_net,
1537 .id = &ct_net_id,
1538 .size = sizeof(struct tc_ct_action_net),
1539 };
1540
ct_init_module(void)1541 static int __init ct_init_module(void)
1542 {
1543 int err;
1544
1545 act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1546 if (!act_ct_wq)
1547 return -ENOMEM;
1548
1549 err = tcf_ct_flow_tables_init();
1550 if (err)
1551 goto err_tbl_init;
1552
1553 err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1554 if (err)
1555 goto err_register;
1556
1557 return 0;
1558
1559 err_register:
1560 tcf_ct_flow_tables_uninit();
1561 err_tbl_init:
1562 destroy_workqueue(act_ct_wq);
1563 return err;
1564 }
1565
ct_cleanup_module(void)1566 static void __exit ct_cleanup_module(void)
1567 {
1568 tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1569 tcf_ct_flow_tables_uninit();
1570 destroy_workqueue(act_ct_wq);
1571 }
1572
1573 module_init(ct_init_module);
1574 module_exit(ct_cleanup_module);
1575 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1576 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1577 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1578 MODULE_DESCRIPTION("Connection tracking action");
1579 MODULE_LICENSE("GPL v2");
1580