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 };
48
49 struct tcf_ct_flow_table {
50 struct rhash_head node; /* In zones tables */
51
52 struct rcu_work rwork;
53 struct nf_flowtable nf_ft;
54 refcount_t ref;
55 struct zones_ht_key key;
56
57 bool dying;
58 };
59
60 static const struct rhashtable_params zones_params = {
61 .head_offset = offsetof(struct tcf_ct_flow_table, node),
62 .key_offset = offsetof(struct tcf_ct_flow_table, key),
63 .key_len = offsetofend(struct zones_ht_key, zone),
64 .automatic_shrinking = true,
65 };
66
67 static struct flow_action_entry *
tcf_ct_flow_table_flow_action_get_next(struct flow_action * flow_action)68 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action)
69 {
70 int i = flow_action->num_entries++;
71
72 return &flow_action->entries[i];
73 }
74
tcf_ct_add_mangle_action(struct flow_action * action,enum flow_action_mangle_base htype,u32 offset,u32 mask,u32 val)75 static void tcf_ct_add_mangle_action(struct flow_action *action,
76 enum flow_action_mangle_base htype,
77 u32 offset,
78 u32 mask,
79 u32 val)
80 {
81 struct flow_action_entry *entry;
82
83 entry = tcf_ct_flow_table_flow_action_get_next(action);
84 entry->id = FLOW_ACTION_MANGLE;
85 entry->mangle.htype = htype;
86 entry->mangle.mask = ~mask;
87 entry->mangle.offset = offset;
88 entry->mangle.val = val;
89 }
90
91 /* The following nat helper functions check if the inverted reverse tuple
92 * (target) is different then the current dir tuple - meaning nat for ports
93 * and/or ip is needed, and add the relevant mangle actions.
94 */
95 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)96 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple,
97 struct nf_conntrack_tuple target,
98 struct flow_action *action)
99 {
100 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
101 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
102 offsetof(struct iphdr, saddr),
103 0xFFFFFFFF,
104 be32_to_cpu(target.src.u3.ip));
105 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
106 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
107 offsetof(struct iphdr, daddr),
108 0xFFFFFFFF,
109 be32_to_cpu(target.dst.u3.ip));
110 }
111
112 static void
tcf_ct_add_ipv6_addr_mangle_action(struct flow_action * action,union nf_inet_addr * addr,u32 offset)113 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action,
114 union nf_inet_addr *addr,
115 u32 offset)
116 {
117 int i;
118
119 for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++)
120 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
121 i * sizeof(u32) + offset,
122 0xFFFFFFFF, be32_to_cpu(addr->ip6[i]));
123 }
124
125 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)126 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple,
127 struct nf_conntrack_tuple target,
128 struct flow_action *action)
129 {
130 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
131 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3,
132 offsetof(struct ipv6hdr,
133 saddr));
134 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
135 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3,
136 offsetof(struct ipv6hdr,
137 daddr));
138 }
139
140 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)141 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple,
142 struct nf_conntrack_tuple target,
143 struct flow_action *action)
144 {
145 __be16 target_src = target.src.u.tcp.port;
146 __be16 target_dst = target.dst.u.tcp.port;
147
148 if (target_src != tuple->src.u.tcp.port)
149 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
150 offsetof(struct tcphdr, source),
151 0xFFFF, be16_to_cpu(target_src));
152 if (target_dst != tuple->dst.u.tcp.port)
153 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
154 offsetof(struct tcphdr, dest),
155 0xFFFF, be16_to_cpu(target_dst));
156 }
157
158 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)159 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple,
160 struct nf_conntrack_tuple target,
161 struct flow_action *action)
162 {
163 __be16 target_src = target.src.u.udp.port;
164 __be16 target_dst = target.dst.u.udp.port;
165
166 if (target_src != tuple->src.u.udp.port)
167 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
168 offsetof(struct udphdr, source),
169 0xFFFF, be16_to_cpu(target_src));
170 if (target_dst != tuple->dst.u.udp.port)
171 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
172 offsetof(struct udphdr, dest),
173 0xFFFF, be16_to_cpu(target_dst));
174 }
175
tcf_ct_flow_table_add_action_meta(struct nf_conn * ct,enum ip_conntrack_dir dir,enum ip_conntrack_info ctinfo,struct flow_action * action)176 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct,
177 enum ip_conntrack_dir dir,
178 enum ip_conntrack_info ctinfo,
179 struct flow_action *action)
180 {
181 struct nf_conn_labels *ct_labels;
182 struct flow_action_entry *entry;
183 u32 *act_ct_labels;
184
185 entry = tcf_ct_flow_table_flow_action_get_next(action);
186 entry->id = FLOW_ACTION_CT_METADATA;
187 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
188 entry->ct_metadata.mark = READ_ONCE(ct->mark);
189 #endif
190 /* aligns with the CT reference on the SKB nf_ct_set */
191 entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
192 entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL;
193
194 act_ct_labels = entry->ct_metadata.labels;
195 ct_labels = nf_ct_labels_find(ct);
196 if (ct_labels)
197 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
198 else
199 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
200 }
201
tcf_ct_flow_table_add_action_nat(struct net * net,struct nf_conn * ct,enum ip_conntrack_dir dir,struct flow_action * action)202 static int tcf_ct_flow_table_add_action_nat(struct net *net,
203 struct nf_conn *ct,
204 enum ip_conntrack_dir dir,
205 struct flow_action *action)
206 {
207 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
208 struct nf_conntrack_tuple target;
209
210 if (!(ct->status & IPS_NAT_MASK))
211 return 0;
212
213 nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
214
215 switch (tuple->src.l3num) {
216 case NFPROTO_IPV4:
217 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
218 action);
219 break;
220 case NFPROTO_IPV6:
221 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
222 action);
223 break;
224 default:
225 return -EOPNOTSUPP;
226 }
227
228 switch (nf_ct_protonum(ct)) {
229 case IPPROTO_TCP:
230 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
231 break;
232 case IPPROTO_UDP:
233 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
234 break;
235 default:
236 return -EOPNOTSUPP;
237 }
238
239 return 0;
240 }
241
tcf_ct_flow_table_fill_actions(struct net * net,struct flow_offload * flow,enum flow_offload_tuple_dir tdir,struct nf_flow_rule * flow_rule)242 static int tcf_ct_flow_table_fill_actions(struct net *net,
243 struct flow_offload *flow,
244 enum flow_offload_tuple_dir tdir,
245 struct nf_flow_rule *flow_rule)
246 {
247 struct flow_action *action = &flow_rule->rule->action;
248 int num_entries = action->num_entries;
249 struct nf_conn *ct = flow->ct;
250 enum ip_conntrack_info ctinfo;
251 enum ip_conntrack_dir dir;
252 int i, err;
253
254 switch (tdir) {
255 case FLOW_OFFLOAD_DIR_ORIGINAL:
256 dir = IP_CT_DIR_ORIGINAL;
257 ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ?
258 IP_CT_ESTABLISHED : IP_CT_NEW;
259 if (ctinfo == IP_CT_ESTABLISHED)
260 set_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags);
261 break;
262 case FLOW_OFFLOAD_DIR_REPLY:
263 dir = IP_CT_DIR_REPLY;
264 ctinfo = IP_CT_ESTABLISHED_REPLY;
265 break;
266 default:
267 return -EOPNOTSUPP;
268 }
269
270 err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
271 if (err)
272 goto err_nat;
273
274 tcf_ct_flow_table_add_action_meta(ct, dir, ctinfo, action);
275 return 0;
276
277 err_nat:
278 /* Clear filled actions */
279 for (i = num_entries; i < action->num_entries; i++)
280 memset(&action->entries[i], 0, sizeof(action->entries[i]));
281 action->num_entries = num_entries;
282
283 return err;
284 }
285
tcf_ct_flow_is_outdated(const struct flow_offload * flow)286 static bool tcf_ct_flow_is_outdated(const struct flow_offload *flow)
287 {
288 return test_bit(IPS_SEEN_REPLY_BIT, &flow->ct->status) &&
289 test_bit(IPS_HW_OFFLOAD_BIT, &flow->ct->status) &&
290 !test_bit(NF_FLOW_HW_PENDING, &flow->flags) &&
291 !test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags);
292 }
293
294 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft);
295
tcf_ct_nf_get(struct nf_flowtable * ft)296 static void tcf_ct_nf_get(struct nf_flowtable *ft)
297 {
298 struct tcf_ct_flow_table *ct_ft =
299 container_of(ft, struct tcf_ct_flow_table, nf_ft);
300
301 tcf_ct_flow_table_get_ref(ct_ft);
302 }
303
304 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft);
305
tcf_ct_nf_put(struct nf_flowtable * ft)306 static void tcf_ct_nf_put(struct nf_flowtable *ft)
307 {
308 struct tcf_ct_flow_table *ct_ft =
309 container_of(ft, struct tcf_ct_flow_table, nf_ft);
310
311 tcf_ct_flow_table_put(ct_ft);
312 }
313
314 static struct nf_flowtable_type flowtable_ct = {
315 .gc = tcf_ct_flow_is_outdated,
316 .action = tcf_ct_flow_table_fill_actions,
317 .get = tcf_ct_nf_get,
318 .put = tcf_ct_nf_put,
319 .owner = THIS_MODULE,
320 };
321
tcf_ct_flow_table_get(struct net * net,struct tcf_ct_params * params)322 static int tcf_ct_flow_table_get(struct net *net, struct tcf_ct_params *params)
323 {
324 struct zones_ht_key key = { .net = net, .zone = params->zone };
325 struct tcf_ct_flow_table *ct_ft;
326 int err = -ENOMEM;
327
328 mutex_lock(&zones_mutex);
329 ct_ft = rhashtable_lookup_fast(&zones_ht, &key, zones_params);
330 if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
331 goto out_unlock;
332
333 ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
334 if (!ct_ft)
335 goto err_alloc;
336 refcount_set(&ct_ft->ref, 1);
337
338 ct_ft->key = key;
339 err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
340 if (err)
341 goto err_insert;
342
343 ct_ft->nf_ft.type = &flowtable_ct;
344 ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD |
345 NF_FLOWTABLE_COUNTER;
346 err = nf_flow_table_init(&ct_ft->nf_ft);
347 if (err)
348 goto err_init;
349 write_pnet(&ct_ft->nf_ft.net, net);
350
351 __module_get(THIS_MODULE);
352 out_unlock:
353 params->ct_ft = ct_ft;
354 params->nf_ft = &ct_ft->nf_ft;
355 mutex_unlock(&zones_mutex);
356
357 return 0;
358
359 err_init:
360 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
361 err_insert:
362 kfree(ct_ft);
363 err_alloc:
364 mutex_unlock(&zones_mutex);
365 return err;
366 }
367
tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table * ct_ft)368 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft)
369 {
370 refcount_inc(&ct_ft->ref);
371 }
372
tcf_ct_flow_table_cleanup_work(struct work_struct * work)373 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
374 {
375 struct tcf_ct_flow_table *ct_ft;
376 struct flow_block *block;
377
378 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
379 rwork);
380 nf_flow_table_free(&ct_ft->nf_ft);
381
382 block = &ct_ft->nf_ft.flow_block;
383 down_write(&ct_ft->nf_ft.flow_block_lock);
384 WARN_ON(!list_empty(&block->cb_list));
385 up_write(&ct_ft->nf_ft.flow_block_lock);
386 kfree(ct_ft);
387
388 module_put(THIS_MODULE);
389 }
390
tcf_ct_flow_table_put(struct tcf_ct_flow_table * ct_ft)391 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft)
392 {
393 if (refcount_dec_and_test(&ct_ft->ref)) {
394 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
395 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
396 queue_rcu_work(act_ct_wq, &ct_ft->rwork);
397 }
398 }
399
tcf_ct_flow_tc_ifidx(struct flow_offload * entry,struct nf_conn_act_ct_ext * act_ct_ext,u8 dir)400 static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry,
401 struct nf_conn_act_ct_ext *act_ct_ext, u8 dir)
402 {
403 entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC;
404 entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir];
405 }
406
tcf_ct_flow_ct_ext_ifidx_update(struct flow_offload * entry)407 static void tcf_ct_flow_ct_ext_ifidx_update(struct flow_offload *entry)
408 {
409 struct nf_conn_act_ct_ext *act_ct_ext;
410
411 act_ct_ext = nf_conn_act_ct_ext_find(entry->ct);
412 if (act_ct_ext) {
413 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
414 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
415 }
416 }
417
tcf_ct_flow_table_add(struct tcf_ct_flow_table * ct_ft,struct nf_conn * ct,bool tcp,bool bidirectional)418 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
419 struct nf_conn *ct,
420 bool tcp, bool bidirectional)
421 {
422 struct nf_conn_act_ct_ext *act_ct_ext;
423 struct flow_offload *entry;
424 int err;
425
426 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
427 return;
428
429 entry = flow_offload_alloc(ct);
430 if (!entry) {
431 WARN_ON_ONCE(1);
432 goto err_alloc;
433 }
434
435 if (tcp) {
436 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
437 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
438 }
439 if (bidirectional)
440 __set_bit(NF_FLOW_HW_BIDIRECTIONAL, &entry->flags);
441
442 act_ct_ext = nf_conn_act_ct_ext_find(ct);
443 if (act_ct_ext) {
444 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
445 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
446 }
447
448 err = flow_offload_add(&ct_ft->nf_ft, entry);
449 if (err)
450 goto err_add;
451
452 return;
453
454 err_add:
455 flow_offload_free(entry);
456 err_alloc:
457 clear_bit(IPS_OFFLOAD_BIT, &ct->status);
458 }
459
tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table * ct_ft,struct nf_conn * ct,enum ip_conntrack_info ctinfo)460 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
461 struct nf_conn *ct,
462 enum ip_conntrack_info ctinfo)
463 {
464 bool tcp = false, bidirectional = true;
465
466 switch (nf_ct_protonum(ct)) {
467 case IPPROTO_TCP:
468 if ((ctinfo != IP_CT_ESTABLISHED &&
469 ctinfo != IP_CT_ESTABLISHED_REPLY) ||
470 !test_bit(IPS_ASSURED_BIT, &ct->status) ||
471 ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
472 return;
473
474 tcp = true;
475 break;
476 case IPPROTO_UDP:
477 if (!nf_ct_is_confirmed(ct))
478 return;
479 if (!test_bit(IPS_ASSURED_BIT, &ct->status))
480 bidirectional = false;
481 break;
482 #ifdef CONFIG_NF_CT_PROTO_GRE
483 case IPPROTO_GRE: {
484 struct nf_conntrack_tuple *tuple;
485
486 if ((ctinfo != IP_CT_ESTABLISHED &&
487 ctinfo != IP_CT_ESTABLISHED_REPLY) ||
488 !test_bit(IPS_ASSURED_BIT, &ct->status) ||
489 ct->status & IPS_NAT_MASK)
490 return;
491
492 tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
493 /* No support for GRE v1 */
494 if (tuple->src.u.gre.key || tuple->dst.u.gre.key)
495 return;
496 break;
497 }
498 #endif
499 default:
500 return;
501 }
502
503 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
504 ct->status & IPS_SEQ_ADJUST)
505 return;
506
507 tcf_ct_flow_table_add(ct_ft, ct, tcp, bidirectional);
508 }
509
510 static bool
tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff * skb,struct flow_offload_tuple * tuple,struct tcphdr ** tcph)511 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
512 struct flow_offload_tuple *tuple,
513 struct tcphdr **tcph)
514 {
515 struct flow_ports *ports;
516 unsigned int thoff;
517 struct iphdr *iph;
518 size_t hdrsize;
519 u8 ipproto;
520
521 if (!pskb_network_may_pull(skb, sizeof(*iph)))
522 return false;
523
524 iph = ip_hdr(skb);
525 thoff = iph->ihl * 4;
526
527 if (ip_is_fragment(iph) ||
528 unlikely(thoff != sizeof(struct iphdr)))
529 return false;
530
531 ipproto = iph->protocol;
532 switch (ipproto) {
533 case IPPROTO_TCP:
534 hdrsize = sizeof(struct tcphdr);
535 break;
536 case IPPROTO_UDP:
537 hdrsize = sizeof(*ports);
538 break;
539 #ifdef CONFIG_NF_CT_PROTO_GRE
540 case IPPROTO_GRE:
541 hdrsize = sizeof(struct gre_base_hdr);
542 break;
543 #endif
544 default:
545 return false;
546 }
547
548 if (iph->ttl <= 1)
549 return false;
550
551 if (!pskb_network_may_pull(skb, thoff + hdrsize))
552 return false;
553
554 switch (ipproto) {
555 case IPPROTO_TCP:
556 *tcph = (void *)(skb_network_header(skb) + thoff);
557 fallthrough;
558 case IPPROTO_UDP:
559 ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
560 tuple->src_port = ports->source;
561 tuple->dst_port = ports->dest;
562 break;
563 case IPPROTO_GRE: {
564 struct gre_base_hdr *greh;
565
566 greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
567 if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
568 return false;
569 break;
570 }
571 }
572
573 iph = ip_hdr(skb);
574
575 tuple->src_v4.s_addr = iph->saddr;
576 tuple->dst_v4.s_addr = iph->daddr;
577 tuple->l3proto = AF_INET;
578 tuple->l4proto = ipproto;
579
580 return true;
581 }
582
583 static bool
tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff * skb,struct flow_offload_tuple * tuple,struct tcphdr ** tcph)584 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
585 struct flow_offload_tuple *tuple,
586 struct tcphdr **tcph)
587 {
588 struct flow_ports *ports;
589 struct ipv6hdr *ip6h;
590 unsigned int thoff;
591 size_t hdrsize;
592 u8 nexthdr;
593
594 if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
595 return false;
596
597 ip6h = ipv6_hdr(skb);
598 thoff = sizeof(*ip6h);
599
600 nexthdr = ip6h->nexthdr;
601 switch (nexthdr) {
602 case IPPROTO_TCP:
603 hdrsize = sizeof(struct tcphdr);
604 break;
605 case IPPROTO_UDP:
606 hdrsize = sizeof(*ports);
607 break;
608 #ifdef CONFIG_NF_CT_PROTO_GRE
609 case IPPROTO_GRE:
610 hdrsize = sizeof(struct gre_base_hdr);
611 break;
612 #endif
613 default:
614 return false;
615 }
616
617 if (ip6h->hop_limit <= 1)
618 return false;
619
620 if (!pskb_network_may_pull(skb, thoff + hdrsize))
621 return false;
622
623 switch (nexthdr) {
624 case IPPROTO_TCP:
625 *tcph = (void *)(skb_network_header(skb) + thoff);
626 fallthrough;
627 case IPPROTO_UDP:
628 ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
629 tuple->src_port = ports->source;
630 tuple->dst_port = ports->dest;
631 break;
632 case IPPROTO_GRE: {
633 struct gre_base_hdr *greh;
634
635 greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
636 if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
637 return false;
638 break;
639 }
640 }
641
642 ip6h = ipv6_hdr(skb);
643
644 tuple->src_v6 = ip6h->saddr;
645 tuple->dst_v6 = ip6h->daddr;
646 tuple->l3proto = AF_INET6;
647 tuple->l4proto = nexthdr;
648
649 return true;
650 }
651
tcf_ct_flow_table_lookup(struct tcf_ct_params * p,struct sk_buff * skb,u8 family)652 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
653 struct sk_buff *skb,
654 u8 family)
655 {
656 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
657 struct flow_offload_tuple_rhash *tuplehash;
658 struct flow_offload_tuple tuple = {};
659 enum ip_conntrack_info ctinfo;
660 struct tcphdr *tcph = NULL;
661 bool force_refresh = false;
662 struct flow_offload *flow;
663 struct nf_conn *ct;
664 u8 dir;
665
666 switch (family) {
667 case NFPROTO_IPV4:
668 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
669 return false;
670 break;
671 case NFPROTO_IPV6:
672 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
673 return false;
674 break;
675 default:
676 return false;
677 }
678
679 tuplehash = flow_offload_lookup(nf_ft, &tuple);
680 if (!tuplehash)
681 return false;
682
683 dir = tuplehash->tuple.dir;
684 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
685 ct = flow->ct;
686
687 if (dir == FLOW_OFFLOAD_DIR_REPLY &&
688 !test_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags)) {
689 /* Only offload reply direction after connection became
690 * assured.
691 */
692 if (test_bit(IPS_ASSURED_BIT, &ct->status))
693 set_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags);
694 else if (test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags))
695 /* If flow_table flow has already been updated to the
696 * established state, then don't refresh.
697 */
698 return false;
699 force_refresh = true;
700 }
701
702 if (tcph && (unlikely(tcph->fin || tcph->rst))) {
703 flow_offload_teardown(flow);
704 return false;
705 }
706
707 if (dir == FLOW_OFFLOAD_DIR_ORIGINAL)
708 ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ?
709 IP_CT_ESTABLISHED : IP_CT_NEW;
710 else
711 ctinfo = IP_CT_ESTABLISHED_REPLY;
712
713 nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
714 tcf_ct_flow_ct_ext_ifidx_update(flow);
715 flow_offload_refresh(nf_ft, flow, force_refresh);
716 if (!test_bit(IPS_ASSURED_BIT, &ct->status)) {
717 /* Process this flow in SW to allow promoting to ASSURED */
718 return false;
719 }
720
721 nf_conntrack_get(&ct->ct_general);
722 nf_ct_set(skb, ct, ctinfo);
723 if (nf_ft->flags & NF_FLOWTABLE_COUNTER)
724 nf_ct_acct_update(ct, dir, skb->len);
725
726 return true;
727 }
728
tcf_ct_flow_tables_init(void)729 static int tcf_ct_flow_tables_init(void)
730 {
731 return rhashtable_init(&zones_ht, &zones_params);
732 }
733
tcf_ct_flow_tables_uninit(void)734 static void tcf_ct_flow_tables_uninit(void)
735 {
736 rhashtable_destroy(&zones_ht);
737 }
738
739 static struct tc_action_ops act_ct_ops;
740
741 struct tc_ct_action_net {
742 struct tc_action_net tn; /* Must be first */
743 };
744
745 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
tcf_ct_skb_nfct_cached(struct net * net,struct sk_buff * skb,struct tcf_ct_params * p)746 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
747 struct tcf_ct_params *p)
748 {
749 enum ip_conntrack_info ctinfo;
750 struct nf_conn *ct;
751
752 ct = nf_ct_get(skb, &ctinfo);
753 if (!ct)
754 return false;
755 if (!net_eq(net, read_pnet(&ct->ct_net)))
756 goto drop_ct;
757 if (nf_ct_zone(ct)->id != p->zone)
758 goto drop_ct;
759 if (p->helper) {
760 struct nf_conn_help *help;
761
762 help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
763 if (help && rcu_access_pointer(help->helper) != p->helper)
764 goto drop_ct;
765 }
766
767 /* Force conntrack entry direction. */
768 if ((p->ct_action & TCA_CT_ACT_FORCE) &&
769 CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
770 if (nf_ct_is_confirmed(ct))
771 nf_ct_kill(ct);
772
773 goto drop_ct;
774 }
775
776 return true;
777
778 drop_ct:
779 nf_ct_put(ct);
780 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
781
782 return false;
783 }
784
tcf_ct_skb_nf_family(struct sk_buff * skb)785 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
786 {
787 u8 family = NFPROTO_UNSPEC;
788
789 switch (skb_protocol(skb, true)) {
790 case htons(ETH_P_IP):
791 family = NFPROTO_IPV4;
792 break;
793 case htons(ETH_P_IPV6):
794 family = NFPROTO_IPV6;
795 break;
796 default:
797 break;
798 }
799
800 return family;
801 }
802
tcf_ct_ipv4_is_fragment(struct sk_buff * skb,bool * frag)803 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
804 {
805 unsigned int len;
806
807 len = skb_network_offset(skb) + sizeof(struct iphdr);
808 if (unlikely(skb->len < len))
809 return -EINVAL;
810 if (unlikely(!pskb_may_pull(skb, len)))
811 return -ENOMEM;
812
813 *frag = ip_is_fragment(ip_hdr(skb));
814 return 0;
815 }
816
tcf_ct_ipv6_is_fragment(struct sk_buff * skb,bool * frag)817 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
818 {
819 unsigned int flags = 0, len, payload_ofs = 0;
820 unsigned short frag_off;
821 int nexthdr;
822
823 len = skb_network_offset(skb) + sizeof(struct ipv6hdr);
824 if (unlikely(skb->len < len))
825 return -EINVAL;
826 if (unlikely(!pskb_may_pull(skb, len)))
827 return -ENOMEM;
828
829 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
830 if (unlikely(nexthdr < 0))
831 return -EPROTO;
832
833 *frag = flags & IP6_FH_F_FRAG;
834 return 0;
835 }
836
tcf_ct_handle_fragments(struct net * net,struct sk_buff * skb,u8 family,u16 zone,bool * defrag)837 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
838 u8 family, u16 zone, bool *defrag)
839 {
840 enum ip_conntrack_info ctinfo;
841 struct nf_conn *ct;
842 int err = 0;
843 bool frag;
844 u8 proto;
845 u16 mru;
846
847 /* Previously seen (loopback)? Ignore. */
848 ct = nf_ct_get(skb, &ctinfo);
849 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
850 return 0;
851
852 if (family == NFPROTO_IPV4)
853 err = tcf_ct_ipv4_is_fragment(skb, &frag);
854 else
855 err = tcf_ct_ipv6_is_fragment(skb, &frag);
856 if (err || !frag)
857 return err;
858
859 err = nf_ct_handle_fragments(net, skb, zone, family, &proto, &mru);
860 if (err)
861 return err;
862
863 *defrag = true;
864 tc_skb_cb(skb)->mru = mru;
865
866 return 0;
867 }
868
tcf_ct_params_free(struct tcf_ct_params * params)869 static void tcf_ct_params_free(struct tcf_ct_params *params)
870 {
871 if (params->helper) {
872 #if IS_ENABLED(CONFIG_NF_NAT)
873 if (params->ct_action & TCA_CT_ACT_NAT)
874 nf_nat_helper_put(params->helper);
875 #endif
876 nf_conntrack_helper_put(params->helper);
877 }
878 if (params->ct_ft)
879 tcf_ct_flow_table_put(params->ct_ft);
880 if (params->tmpl) {
881 if (params->put_labels)
882 nf_connlabels_put(nf_ct_net(params->tmpl));
883
884 nf_ct_put(params->tmpl);
885 }
886
887 kfree(params);
888 }
889
tcf_ct_params_free_rcu(struct rcu_head * head)890 static void tcf_ct_params_free_rcu(struct rcu_head *head)
891 {
892 struct tcf_ct_params *params;
893
894 params = container_of(head, struct tcf_ct_params, rcu);
895 tcf_ct_params_free(params);
896 }
897
tcf_ct_act_set_mark(struct nf_conn * ct,u32 mark,u32 mask)898 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
899 {
900 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
901 u32 new_mark;
902
903 if (!mask)
904 return;
905
906 new_mark = mark | (READ_ONCE(ct->mark) & ~(mask));
907 if (READ_ONCE(ct->mark) != new_mark) {
908 WRITE_ONCE(ct->mark, new_mark);
909 if (nf_ct_is_confirmed(ct))
910 nf_conntrack_event_cache(IPCT_MARK, ct);
911 }
912 #endif
913 }
914
tcf_ct_act_set_labels(struct nf_conn * ct,u32 * labels,u32 * labels_m)915 static void tcf_ct_act_set_labels(struct nf_conn *ct,
916 u32 *labels,
917 u32 *labels_m)
918 {
919 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
920 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
921
922 if (!memchr_inv(labels_m, 0, labels_sz))
923 return;
924
925 nf_connlabels_replace(ct, labels, labels_m, 4);
926 #endif
927 }
928
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)929 static int tcf_ct_act_nat(struct sk_buff *skb,
930 struct nf_conn *ct,
931 enum ip_conntrack_info ctinfo,
932 int ct_action,
933 struct nf_nat_range2 *range,
934 bool commit)
935 {
936 #if IS_ENABLED(CONFIG_NF_NAT)
937 int err, action = 0;
938
939 if (!(ct_action & TCA_CT_ACT_NAT))
940 return NF_ACCEPT;
941 if (ct_action & TCA_CT_ACT_NAT_SRC)
942 action |= BIT(NF_NAT_MANIP_SRC);
943 if (ct_action & TCA_CT_ACT_NAT_DST)
944 action |= BIT(NF_NAT_MANIP_DST);
945
946 err = nf_ct_nat(skb, ct, ctinfo, &action, range, commit);
947 if (err != NF_ACCEPT)
948 return err & NF_VERDICT_MASK;
949
950 if (action & BIT(NF_NAT_MANIP_SRC))
951 tc_skb_cb(skb)->post_ct_snat = 1;
952 if (action & BIT(NF_NAT_MANIP_DST))
953 tc_skb_cb(skb)->post_ct_dnat = 1;
954
955 return err;
956 #else
957 return NF_ACCEPT;
958 #endif
959 }
960
tcf_ct_act(struct sk_buff * skb,const struct tc_action * a,struct tcf_result * res)961 TC_INDIRECT_SCOPE int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
962 struct tcf_result *res)
963 {
964 struct net *net = dev_net(skb->dev);
965 enum ip_conntrack_info ctinfo;
966 struct tcf_ct *c = to_ct(a);
967 struct nf_conn *tmpl = NULL;
968 struct nf_hook_state state;
969 bool cached, commit, clear;
970 int nh_ofs, err, retval;
971 struct tcf_ct_params *p;
972 bool add_helper = false;
973 bool skip_add = false;
974 bool defrag = false;
975 struct nf_conn *ct;
976 u8 family;
977
978 p = rcu_dereference_bh(c->params);
979
980 retval = READ_ONCE(c->tcf_action);
981 commit = p->ct_action & TCA_CT_ACT_COMMIT;
982 clear = p->ct_action & TCA_CT_ACT_CLEAR;
983 tmpl = p->tmpl;
984
985 tcf_lastuse_update(&c->tcf_tm);
986 tcf_action_update_bstats(&c->common, skb);
987
988 if (clear) {
989 tc_skb_cb(skb)->post_ct = false;
990 ct = nf_ct_get(skb, &ctinfo);
991 if (ct) {
992 nf_ct_put(ct);
993 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
994 }
995
996 goto out_clear;
997 }
998
999 family = tcf_ct_skb_nf_family(skb);
1000 if (family == NFPROTO_UNSPEC)
1001 goto drop;
1002
1003 /* The conntrack module expects to be working at L3.
1004 * We also try to pull the IPv4/6 header to linear area
1005 */
1006 nh_ofs = skb_network_offset(skb);
1007 skb_pull_rcsum(skb, nh_ofs);
1008 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
1009 if (err)
1010 goto out_frag;
1011
1012 err = nf_ct_skb_network_trim(skb, family);
1013 if (err)
1014 goto drop;
1015
1016 /* If we are recirculating packets to match on ct fields and
1017 * committing with a separate ct action, then we don't need to
1018 * actually run the packet through conntrack twice unless it's for a
1019 * different zone.
1020 */
1021 cached = tcf_ct_skb_nfct_cached(net, skb, p);
1022 if (!cached) {
1023 if (tcf_ct_flow_table_lookup(p, skb, family)) {
1024 skip_add = true;
1025 goto do_nat;
1026 }
1027
1028 /* Associate skb with specified zone. */
1029 if (tmpl) {
1030 nf_conntrack_put(skb_nfct(skb));
1031 nf_conntrack_get(&tmpl->ct_general);
1032 nf_ct_set(skb, tmpl, IP_CT_NEW);
1033 }
1034
1035 state.hook = NF_INET_PRE_ROUTING;
1036 state.net = net;
1037 state.pf = family;
1038 err = nf_conntrack_in(skb, &state);
1039 if (err != NF_ACCEPT)
1040 goto nf_error;
1041 }
1042
1043 do_nat:
1044 ct = nf_ct_get(skb, &ctinfo);
1045 if (!ct)
1046 goto out_push;
1047 nf_ct_deliver_cached_events(ct);
1048 nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
1049
1050 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1051 if (err != NF_ACCEPT)
1052 goto nf_error;
1053
1054 if (!nf_ct_is_confirmed(ct) && commit && p->helper && !nfct_help(ct)) {
1055 err = __nf_ct_try_assign_helper(ct, p->tmpl, GFP_ATOMIC);
1056 if (err)
1057 goto drop;
1058 add_helper = true;
1059 if (p->ct_action & TCA_CT_ACT_NAT && !nfct_seqadj(ct)) {
1060 if (!nfct_seqadj_ext_add(ct))
1061 goto drop;
1062 }
1063 }
1064
1065 if (nf_ct_is_confirmed(ct) ? ((!cached && !skip_add) || add_helper) : commit) {
1066 err = nf_ct_helper(skb, ct, ctinfo, family);
1067 if (err != NF_ACCEPT)
1068 goto nf_error;
1069 }
1070
1071 if (commit) {
1072 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1073 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1074
1075 if (!nf_ct_is_confirmed(ct))
1076 nf_conn_act_ct_ext_add(skb, ct, ctinfo);
1077
1078 /* This will take care of sending queued events
1079 * even if the connection is already confirmed.
1080 */
1081 err = nf_conntrack_confirm(skb);
1082 if (err != NF_ACCEPT)
1083 goto nf_error;
1084
1085 /* The ct may be dropped if a clash has been resolved,
1086 * so it's necessary to retrieve it from skb again to
1087 * prevent UAF.
1088 */
1089 ct = nf_ct_get(skb, &ctinfo);
1090 if (!ct)
1091 skip_add = true;
1092 }
1093
1094 if (!skip_add)
1095 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1096
1097 out_push:
1098 skb_push_rcsum(skb, nh_ofs);
1099
1100 tc_skb_cb(skb)->post_ct = true;
1101 tc_skb_cb(skb)->zone = p->zone;
1102 out_clear:
1103 if (defrag)
1104 qdisc_skb_cb(skb)->pkt_len = skb->len;
1105 return retval;
1106
1107 out_frag:
1108 if (err != -EINPROGRESS)
1109 tcf_action_inc_drop_qstats(&c->common);
1110 return TC_ACT_CONSUMED;
1111
1112 drop:
1113 tcf_action_inc_drop_qstats(&c->common);
1114 return TC_ACT_SHOT;
1115
1116 nf_error:
1117 /* some verdicts store extra data in upper bits, such
1118 * as errno or queue number.
1119 */
1120 switch (err & NF_VERDICT_MASK) {
1121 case NF_DROP:
1122 goto drop;
1123 case NF_STOLEN:
1124 tcf_action_inc_drop_qstats(&c->common);
1125 return TC_ACT_CONSUMED;
1126 default:
1127 DEBUG_NET_WARN_ON_ONCE(1);
1128 goto drop;
1129 }
1130 }
1131
1132 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1133 [TCA_CT_ACTION] = { .type = NLA_U16 },
1134 [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)),
1135 [TCA_CT_ZONE] = { .type = NLA_U16 },
1136 [TCA_CT_MARK] = { .type = NLA_U32 },
1137 [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1138 [TCA_CT_LABELS] = { .type = NLA_BINARY,
1139 .len = 128 / BITS_PER_BYTE },
1140 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1141 .len = 128 / BITS_PER_BYTE },
1142 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1143 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1144 [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1145 [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1146 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1147 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1148 [TCA_CT_HELPER_NAME] = { .type = NLA_STRING, .len = NF_CT_HELPER_NAME_LEN },
1149 [TCA_CT_HELPER_FAMILY] = { .type = NLA_U8 },
1150 [TCA_CT_HELPER_PROTO] = { .type = NLA_U8 },
1151 };
1152
tcf_ct_fill_params_nat(struct tcf_ct_params * p,struct tc_ct * parm,struct nlattr ** tb,struct netlink_ext_ack * extack)1153 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1154 struct tc_ct *parm,
1155 struct nlattr **tb,
1156 struct netlink_ext_ack *extack)
1157 {
1158 struct nf_nat_range2 *range;
1159
1160 if (!(p->ct_action & TCA_CT_ACT_NAT))
1161 return 0;
1162
1163 if (!IS_ENABLED(CONFIG_NF_NAT)) {
1164 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1165 return -EOPNOTSUPP;
1166 }
1167
1168 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1169 return 0;
1170
1171 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1172 (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1173 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1174 return -EOPNOTSUPP;
1175 }
1176
1177 range = &p->range;
1178 if (tb[TCA_CT_NAT_IPV4_MIN]) {
1179 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1180
1181 p->ipv4_range = true;
1182 range->flags |= NF_NAT_RANGE_MAP_IPS;
1183 range->min_addr.ip =
1184 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1185
1186 range->max_addr.ip = max_attr ?
1187 nla_get_in_addr(max_attr) :
1188 range->min_addr.ip;
1189 } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1190 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1191
1192 p->ipv4_range = false;
1193 range->flags |= NF_NAT_RANGE_MAP_IPS;
1194 range->min_addr.in6 =
1195 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1196
1197 range->max_addr.in6 = max_attr ?
1198 nla_get_in6_addr(max_attr) :
1199 range->min_addr.in6;
1200 }
1201
1202 if (tb[TCA_CT_NAT_PORT_MIN]) {
1203 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1204 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1205
1206 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1207 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1208 range->min_proto.all;
1209 }
1210
1211 return 0;
1212 }
1213
tcf_ct_set_key_val(struct nlattr ** tb,void * val,int val_type,void * mask,int mask_type,int len)1214 static void tcf_ct_set_key_val(struct nlattr **tb,
1215 void *val, int val_type,
1216 void *mask, int mask_type,
1217 int len)
1218 {
1219 if (!tb[val_type])
1220 return;
1221 nla_memcpy(val, tb[val_type], len);
1222
1223 if (!mask)
1224 return;
1225
1226 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1227 memset(mask, 0xff, len);
1228 else
1229 nla_memcpy(mask, tb[mask_type], len);
1230 }
1231
tcf_ct_fill_params(struct net * net,struct tcf_ct_params * p,struct tc_ct * parm,struct nlattr ** tb,struct netlink_ext_ack * extack)1232 static int tcf_ct_fill_params(struct net *net,
1233 struct tcf_ct_params *p,
1234 struct tc_ct *parm,
1235 struct nlattr **tb,
1236 struct netlink_ext_ack *extack)
1237 {
1238 struct nf_conntrack_zone zone;
1239 int err, family, proto, len;
1240 bool put_labels = false;
1241 struct nf_conn *tmpl;
1242 char *name;
1243
1244 p->zone = NF_CT_DEFAULT_ZONE_ID;
1245
1246 tcf_ct_set_key_val(tb,
1247 &p->ct_action, TCA_CT_ACTION,
1248 NULL, TCA_CT_UNSPEC,
1249 sizeof(p->ct_action));
1250
1251 if (p->ct_action & TCA_CT_ACT_CLEAR)
1252 return 0;
1253
1254 err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1255 if (err)
1256 return err;
1257
1258 if (tb[TCA_CT_MARK]) {
1259 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1260 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1261 return -EOPNOTSUPP;
1262 }
1263 tcf_ct_set_key_val(tb,
1264 &p->mark, TCA_CT_MARK,
1265 &p->mark_mask, TCA_CT_MARK_MASK,
1266 sizeof(p->mark));
1267 }
1268
1269 if (tb[TCA_CT_LABELS]) {
1270 unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1271
1272 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1273 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1274 return -EOPNOTSUPP;
1275 }
1276
1277 if (nf_connlabels_get(net, n_bits - 1)) {
1278 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1279 return -EOPNOTSUPP;
1280 } else {
1281 put_labels = true;
1282 }
1283
1284 tcf_ct_set_key_val(tb,
1285 p->labels, TCA_CT_LABELS,
1286 p->labels_mask, TCA_CT_LABELS_MASK,
1287 sizeof(p->labels));
1288 }
1289
1290 if (tb[TCA_CT_ZONE]) {
1291 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1292 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1293 return -EOPNOTSUPP;
1294 }
1295
1296 tcf_ct_set_key_val(tb,
1297 &p->zone, TCA_CT_ZONE,
1298 NULL, TCA_CT_UNSPEC,
1299 sizeof(p->zone));
1300 }
1301
1302 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1303 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1304 if (!tmpl) {
1305 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1306 return -ENOMEM;
1307 }
1308 p->tmpl = tmpl;
1309 if (tb[TCA_CT_HELPER_NAME]) {
1310 name = nla_data(tb[TCA_CT_HELPER_NAME]);
1311 len = nla_len(tb[TCA_CT_HELPER_NAME]);
1312 if (len > 16 || name[len - 1] != '\0') {
1313 NL_SET_ERR_MSG_MOD(extack, "Failed to parse helper name.");
1314 err = -EINVAL;
1315 goto err;
1316 }
1317 family = tb[TCA_CT_HELPER_FAMILY] ? nla_get_u8(tb[TCA_CT_HELPER_FAMILY]) : AF_INET;
1318 proto = tb[TCA_CT_HELPER_PROTO] ? nla_get_u8(tb[TCA_CT_HELPER_PROTO]) : IPPROTO_TCP;
1319 err = nf_ct_add_helper(tmpl, name, family, proto,
1320 p->ct_action & TCA_CT_ACT_NAT, &p->helper);
1321 if (err) {
1322 NL_SET_ERR_MSG_MOD(extack, "Failed to add helper");
1323 goto err;
1324 }
1325 }
1326
1327 p->put_labels = put_labels;
1328
1329 if (p->ct_action & TCA_CT_ACT_COMMIT)
1330 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1331 return 0;
1332 err:
1333 if (put_labels)
1334 nf_connlabels_put(net);
1335
1336 nf_ct_put(p->tmpl);
1337 p->tmpl = NULL;
1338 return err;
1339 }
1340
tcf_ct_init(struct net * net,struct nlattr * nla,struct nlattr * est,struct tc_action ** a,struct tcf_proto * tp,u32 flags,struct netlink_ext_ack * extack)1341 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1342 struct nlattr *est, struct tc_action **a,
1343 struct tcf_proto *tp, u32 flags,
1344 struct netlink_ext_ack *extack)
1345 {
1346 struct tc_action_net *tn = net_generic(net, act_ct_ops.net_id);
1347 bool bind = flags & TCA_ACT_FLAGS_BIND;
1348 struct tcf_ct_params *params = NULL;
1349 struct nlattr *tb[TCA_CT_MAX + 1];
1350 struct tcf_chain *goto_ch = NULL;
1351 struct tc_ct *parm;
1352 struct tcf_ct *c;
1353 int err, res = 0;
1354 u32 index;
1355
1356 if (!nla) {
1357 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1358 return -EINVAL;
1359 }
1360
1361 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1362 if (err < 0)
1363 return err;
1364
1365 if (!tb[TCA_CT_PARMS]) {
1366 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1367 return -EINVAL;
1368 }
1369 parm = nla_data(tb[TCA_CT_PARMS]);
1370 index = parm->index;
1371 err = tcf_idr_check_alloc(tn, &index, a, bind);
1372 if (err < 0)
1373 return err;
1374
1375 if (!err) {
1376 err = tcf_idr_create_from_flags(tn, index, est, a,
1377 &act_ct_ops, bind, flags);
1378 if (err) {
1379 tcf_idr_cleanup(tn, index);
1380 return err;
1381 }
1382 res = ACT_P_CREATED;
1383 } else {
1384 if (bind)
1385 return ACT_P_BOUND;
1386
1387 if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
1388 tcf_idr_release(*a, bind);
1389 return -EEXIST;
1390 }
1391 }
1392 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1393 if (err < 0)
1394 goto cleanup;
1395
1396 c = to_ct(*a);
1397
1398 params = kzalloc(sizeof(*params), GFP_KERNEL);
1399 if (unlikely(!params)) {
1400 err = -ENOMEM;
1401 goto cleanup;
1402 }
1403
1404 err = tcf_ct_fill_params(net, params, parm, tb, extack);
1405 if (err)
1406 goto cleanup;
1407
1408 err = tcf_ct_flow_table_get(net, params);
1409 if (err)
1410 goto cleanup;
1411
1412 spin_lock_bh(&c->tcf_lock);
1413 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1414 params = rcu_replace_pointer(c->params, params,
1415 lockdep_is_held(&c->tcf_lock));
1416 spin_unlock_bh(&c->tcf_lock);
1417
1418 if (goto_ch)
1419 tcf_chain_put_by_act(goto_ch);
1420 if (params)
1421 call_rcu(¶ms->rcu, tcf_ct_params_free_rcu);
1422
1423 return res;
1424
1425 cleanup:
1426 if (goto_ch)
1427 tcf_chain_put_by_act(goto_ch);
1428 if (params)
1429 tcf_ct_params_free(params);
1430 tcf_idr_release(*a, bind);
1431 return err;
1432 }
1433
tcf_ct_cleanup(struct tc_action * a)1434 static void tcf_ct_cleanup(struct tc_action *a)
1435 {
1436 struct tcf_ct_params *params;
1437 struct tcf_ct *c = to_ct(a);
1438
1439 params = rcu_dereference_protected(c->params, 1);
1440 if (params)
1441 call_rcu(¶ms->rcu, tcf_ct_params_free_rcu);
1442 }
1443
tcf_ct_dump_key_val(struct sk_buff * skb,void * val,int val_type,void * mask,int mask_type,int len)1444 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1445 void *val, int val_type,
1446 void *mask, int mask_type,
1447 int len)
1448 {
1449 int err;
1450
1451 if (mask && !memchr_inv(mask, 0, len))
1452 return 0;
1453
1454 err = nla_put(skb, val_type, len, val);
1455 if (err)
1456 return err;
1457
1458 if (mask_type != TCA_CT_UNSPEC) {
1459 err = nla_put(skb, mask_type, len, mask);
1460 if (err)
1461 return err;
1462 }
1463
1464 return 0;
1465 }
1466
tcf_ct_dump_nat(struct sk_buff * skb,struct tcf_ct_params * p)1467 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1468 {
1469 struct nf_nat_range2 *range = &p->range;
1470
1471 if (!(p->ct_action & TCA_CT_ACT_NAT))
1472 return 0;
1473
1474 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1475 return 0;
1476
1477 if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1478 if (p->ipv4_range) {
1479 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1480 range->min_addr.ip))
1481 return -1;
1482 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1483 range->max_addr.ip))
1484 return -1;
1485 } else {
1486 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1487 &range->min_addr.in6))
1488 return -1;
1489 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1490 &range->max_addr.in6))
1491 return -1;
1492 }
1493 }
1494
1495 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1496 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1497 range->min_proto.all))
1498 return -1;
1499 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1500 range->max_proto.all))
1501 return -1;
1502 }
1503
1504 return 0;
1505 }
1506
tcf_ct_dump_helper(struct sk_buff * skb,struct nf_conntrack_helper * helper)1507 static int tcf_ct_dump_helper(struct sk_buff *skb, struct nf_conntrack_helper *helper)
1508 {
1509 if (!helper)
1510 return 0;
1511
1512 if (nla_put_string(skb, TCA_CT_HELPER_NAME, helper->name) ||
1513 nla_put_u8(skb, TCA_CT_HELPER_FAMILY, helper->tuple.src.l3num) ||
1514 nla_put_u8(skb, TCA_CT_HELPER_PROTO, helper->tuple.dst.protonum))
1515 return -1;
1516
1517 return 0;
1518 }
1519
tcf_ct_dump(struct sk_buff * skb,struct tc_action * a,int bind,int ref)1520 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1521 int bind, int ref)
1522 {
1523 unsigned char *b = skb_tail_pointer(skb);
1524 struct tcf_ct *c = to_ct(a);
1525 struct tcf_ct_params *p;
1526
1527 struct tc_ct opt = {
1528 .index = c->tcf_index,
1529 .refcnt = refcount_read(&c->tcf_refcnt) - ref,
1530 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1531 };
1532 struct tcf_t t;
1533
1534 spin_lock_bh(&c->tcf_lock);
1535 p = rcu_dereference_protected(c->params,
1536 lockdep_is_held(&c->tcf_lock));
1537 opt.action = c->tcf_action;
1538
1539 if (tcf_ct_dump_key_val(skb,
1540 &p->ct_action, TCA_CT_ACTION,
1541 NULL, TCA_CT_UNSPEC,
1542 sizeof(p->ct_action)))
1543 goto nla_put_failure;
1544
1545 if (p->ct_action & TCA_CT_ACT_CLEAR)
1546 goto skip_dump;
1547
1548 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1549 tcf_ct_dump_key_val(skb,
1550 &p->mark, TCA_CT_MARK,
1551 &p->mark_mask, TCA_CT_MARK_MASK,
1552 sizeof(p->mark)))
1553 goto nla_put_failure;
1554
1555 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1556 tcf_ct_dump_key_val(skb,
1557 p->labels, TCA_CT_LABELS,
1558 p->labels_mask, TCA_CT_LABELS_MASK,
1559 sizeof(p->labels)))
1560 goto nla_put_failure;
1561
1562 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1563 tcf_ct_dump_key_val(skb,
1564 &p->zone, TCA_CT_ZONE,
1565 NULL, TCA_CT_UNSPEC,
1566 sizeof(p->zone)))
1567 goto nla_put_failure;
1568
1569 if (tcf_ct_dump_nat(skb, p))
1570 goto nla_put_failure;
1571
1572 if (tcf_ct_dump_helper(skb, p->helper))
1573 goto nla_put_failure;
1574
1575 skip_dump:
1576 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1577 goto nla_put_failure;
1578
1579 tcf_tm_dump(&t, &c->tcf_tm);
1580 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1581 goto nla_put_failure;
1582 spin_unlock_bh(&c->tcf_lock);
1583
1584 return skb->len;
1585 nla_put_failure:
1586 spin_unlock_bh(&c->tcf_lock);
1587 nlmsg_trim(skb, b);
1588 return -1;
1589 }
1590
tcf_stats_update(struct tc_action * a,u64 bytes,u64 packets,u64 drops,u64 lastuse,bool hw)1591 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1592 u64 drops, u64 lastuse, bool hw)
1593 {
1594 struct tcf_ct *c = to_ct(a);
1595
1596 tcf_action_update_stats(a, bytes, packets, drops, hw);
1597 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1598 }
1599
tcf_ct_offload_act_setup(struct tc_action * act,void * entry_data,u32 * index_inc,bool bind,struct netlink_ext_ack * extack)1600 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data,
1601 u32 *index_inc, bool bind,
1602 struct netlink_ext_ack *extack)
1603 {
1604 if (bind) {
1605 struct flow_action_entry *entry = entry_data;
1606
1607 if (tcf_ct_helper(act))
1608 return -EOPNOTSUPP;
1609
1610 entry->id = FLOW_ACTION_CT;
1611 entry->ct.action = tcf_ct_action(act);
1612 entry->ct.zone = tcf_ct_zone(act);
1613 entry->ct.flow_table = tcf_ct_ft(act);
1614 *index_inc = 1;
1615 } else {
1616 struct flow_offload_action *fl_action = entry_data;
1617
1618 fl_action->id = FLOW_ACTION_CT;
1619 }
1620
1621 return 0;
1622 }
1623
1624 static struct tc_action_ops act_ct_ops = {
1625 .kind = "ct",
1626 .id = TCA_ID_CT,
1627 .owner = THIS_MODULE,
1628 .act = tcf_ct_act,
1629 .dump = tcf_ct_dump,
1630 .init = tcf_ct_init,
1631 .cleanup = tcf_ct_cleanup,
1632 .stats_update = tcf_stats_update,
1633 .offload_act_setup = tcf_ct_offload_act_setup,
1634 .size = sizeof(struct tcf_ct),
1635 };
1636 MODULE_ALIAS_NET_ACT("ct");
1637
ct_init_net(struct net * net)1638 static __net_init int ct_init_net(struct net *net)
1639 {
1640 struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1641
1642 return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1643 }
1644
ct_exit_net(struct list_head * net_list)1645 static void __net_exit ct_exit_net(struct list_head *net_list)
1646 {
1647 tc_action_net_exit(net_list, act_ct_ops.net_id);
1648 }
1649
1650 static struct pernet_operations ct_net_ops = {
1651 .init = ct_init_net,
1652 .exit_batch = ct_exit_net,
1653 .id = &act_ct_ops.net_id,
1654 .size = sizeof(struct tc_ct_action_net),
1655 };
1656
ct_init_module(void)1657 static int __init ct_init_module(void)
1658 {
1659 int err;
1660
1661 act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1662 if (!act_ct_wq)
1663 return -ENOMEM;
1664
1665 err = tcf_ct_flow_tables_init();
1666 if (err)
1667 goto err_tbl_init;
1668
1669 err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1670 if (err)
1671 goto err_register;
1672
1673 static_branch_inc(&tcf_frag_xmit_count);
1674
1675 return 0;
1676
1677 err_register:
1678 tcf_ct_flow_tables_uninit();
1679 err_tbl_init:
1680 destroy_workqueue(act_ct_wq);
1681 return err;
1682 }
1683
ct_cleanup_module(void)1684 static void __exit ct_cleanup_module(void)
1685 {
1686 static_branch_dec(&tcf_frag_xmit_count);
1687 tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1688 tcf_ct_flow_tables_uninit();
1689 destroy_workqueue(act_ct_wq);
1690 }
1691
1692 module_init(ct_init_module);
1693 module_exit(ct_cleanup_module);
1694 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1695 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1696 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1697 MODULE_DESCRIPTION("Connection tracking action");
1698 MODULE_LICENSE("GPL v2");
1699