1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * This is a module which is used for queueing packets and communicating with
4 * userspace via nfnetlink.
5 *
6 * (C) 2005 by Harald Welte <laforge@netfilter.org>
7 * (C) 2007 by Patrick McHardy <kaber@trash.net>
8 *
9 * Based on the old ipv4-only ip_queue.c:
10 * (C) 2000-2002 James Morris <jmorris@intercode.com.au>
11 * (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
12 */
13
14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16#include <linux/module.h>
17#include <linux/skbuff.h>
18#include <linux/init.h>
19#include <linux/spinlock.h>
20#include <linux/slab.h>
21#include <linux/notifier.h>
22#include <linux/netdevice.h>
23#include <linux/netfilter.h>
24#include <linux/proc_fs.h>
25#include <linux/netfilter_ipv4.h>
26#include <linux/netfilter_ipv6.h>
27#include <linux/netfilter_bridge.h>
28#include <linux/netfilter/nfnetlink.h>
29#include <linux/netfilter/nfnetlink_queue.h>
30#include <linux/netfilter/nf_conntrack_common.h>
31#include <linux/list.h>
32#include <linux/cgroup-defs.h>
33#include <net/gso.h>
34#include <net/sock.h>
35#include <net/tcp_states.h>
36#include <net/netfilter/nf_queue.h>
37#include <net/netns/generic.h>
38
39#include <linux/atomic.h>
40
41#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
42#include "../bridge/br_private.h"
43#endif
44
45#if IS_ENABLED(CONFIG_NF_CONNTRACK)
46#include <net/netfilter/nf_conntrack.h>
47#endif
48
49#define NFQNL_QMAX_DEFAULT 1024
50
51/* We're using struct nlattr which has 16bit nla_len. Note that nla_len
52 * includes the header length. Thus, the maximum packet length that we
53 * support is 65531 bytes. We send truncated packets if the specified length
54 * is larger than that. Userspace can check for presence of NFQA_CAP_LEN
55 * attribute to detect truncation.
56 */
57#define NFQNL_MAX_COPY_RANGE (0xffff - NLA_HDRLEN)
58
59struct nfqnl_instance {
60 struct hlist_node hlist; /* global list of queues */
61 struct rcu_head rcu;
62
63 u32 peer_portid;
64 unsigned int queue_maxlen;
65 unsigned int copy_range;
66 unsigned int queue_dropped;
67 unsigned int queue_user_dropped;
68
69
70 u_int16_t queue_num; /* number of this queue */
71 u_int8_t copy_mode;
72 u_int32_t flags; /* Set using NFQA_CFG_FLAGS */
73/*
74 * Following fields are dirtied for each queued packet,
75 * keep them in same cache line if possible.
76 */
77 spinlock_t lock ____cacheline_aligned_in_smp;
78 unsigned int queue_total;
79 unsigned int id_sequence; /* 'sequence' of pkt ids */
80 struct list_head queue_list; /* packets in queue */
81};
82
83typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
84
85static unsigned int nfnl_queue_net_id __read_mostly;
86
87#define INSTANCE_BUCKETS 16
88struct nfnl_queue_net {
89 spinlock_t instances_lock;
90 struct hlist_head instance_table[INSTANCE_BUCKETS];
91};
92
93static struct nfnl_queue_net *nfnl_queue_pernet(struct net *net)
94{
95 return net_generic(net, id: nfnl_queue_net_id);
96}
97
98static inline u_int8_t instance_hashfn(u_int16_t queue_num)
99{
100 return ((queue_num >> 8) ^ queue_num) % INSTANCE_BUCKETS;
101}
102
103static struct nfqnl_instance *
104instance_lookup(struct nfnl_queue_net *q, u_int16_t queue_num)
105{
106 struct hlist_head *head;
107 struct nfqnl_instance *inst;
108
109 head = &q->instance_table[instance_hashfn(queue_num)];
110 hlist_for_each_entry_rcu(inst, head, hlist) {
111 if (inst->queue_num == queue_num)
112 return inst;
113 }
114 return NULL;
115}
116
117static struct nfqnl_instance *
118instance_create(struct nfnl_queue_net *q, u_int16_t queue_num, u32 portid)
119{
120 struct nfqnl_instance *inst;
121 unsigned int h;
122 int err;
123
124 spin_lock(lock: &q->instances_lock);
125 if (instance_lookup(q, queue_num)) {
126 err = -EEXIST;
127 goto out_unlock;
128 }
129
130 inst = kzalloc(size: sizeof(*inst), GFP_ATOMIC);
131 if (!inst) {
132 err = -ENOMEM;
133 goto out_unlock;
134 }
135
136 inst->queue_num = queue_num;
137 inst->peer_portid = portid;
138 inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
139 inst->copy_range = NFQNL_MAX_COPY_RANGE;
140 inst->copy_mode = NFQNL_COPY_NONE;
141 spin_lock_init(&inst->lock);
142 INIT_LIST_HEAD(list: &inst->queue_list);
143
144 if (!try_module_get(THIS_MODULE)) {
145 err = -EAGAIN;
146 goto out_free;
147 }
148
149 h = instance_hashfn(queue_num);
150 hlist_add_head_rcu(n: &inst->hlist, h: &q->instance_table[h]);
151
152 spin_unlock(lock: &q->instances_lock);
153
154 return inst;
155
156out_free:
157 kfree(objp: inst);
158out_unlock:
159 spin_unlock(lock: &q->instances_lock);
160 return ERR_PTR(error: err);
161}
162
163static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
164 unsigned long data);
165
166static void
167instance_destroy_rcu(struct rcu_head *head)
168{
169 struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
170 rcu);
171
172 nfqnl_flush(queue: inst, NULL, data: 0);
173 kfree(objp: inst);
174 module_put(THIS_MODULE);
175}
176
177static void
178__instance_destroy(struct nfqnl_instance *inst)
179{
180 hlist_del_rcu(n: &inst->hlist);
181 call_rcu(head: &inst->rcu, func: instance_destroy_rcu);
182}
183
184static void
185instance_destroy(struct nfnl_queue_net *q, struct nfqnl_instance *inst)
186{
187 spin_lock(lock: &q->instances_lock);
188 __instance_destroy(inst);
189 spin_unlock(lock: &q->instances_lock);
190}
191
192static inline void
193__enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
194{
195 list_add_tail(new: &entry->list, head: &queue->queue_list);
196 queue->queue_total++;
197}
198
199static void
200__dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
201{
202 list_del(entry: &entry->list);
203 queue->queue_total--;
204}
205
206static struct nf_queue_entry *
207find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
208{
209 struct nf_queue_entry *entry = NULL, *i;
210
211 spin_lock_bh(lock: &queue->lock);
212
213 list_for_each_entry(i, &queue->queue_list, list) {
214 if (i->id == id) {
215 entry = i;
216 break;
217 }
218 }
219
220 if (entry)
221 __dequeue_entry(queue, entry);
222
223 spin_unlock_bh(lock: &queue->lock);
224
225 return entry;
226}
227
228static unsigned int nf_iterate(struct sk_buff *skb,
229 struct nf_hook_state *state,
230 const struct nf_hook_entries *hooks,
231 unsigned int *index)
232{
233 const struct nf_hook_entry *hook;
234 unsigned int verdict, i = *index;
235
236 while (i < hooks->num_hook_entries) {
237 hook = &hooks->hooks[i];
238repeat:
239 verdict = nf_hook_entry_hookfn(entry: hook, skb, state);
240 if (verdict != NF_ACCEPT) {
241 *index = i;
242 if (verdict != NF_REPEAT)
243 return verdict;
244 goto repeat;
245 }
246 i++;
247 }
248
249 *index = i;
250 return NF_ACCEPT;
251}
252
253static struct nf_hook_entries *nf_hook_entries_head(const struct net *net, u8 pf, u8 hooknum)
254{
255 switch (pf) {
256#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
257 case NFPROTO_BRIDGE:
258 return rcu_dereference(net->nf.hooks_bridge[hooknum]);
259#endif
260 case NFPROTO_IPV4:
261 return rcu_dereference(net->nf.hooks_ipv4[hooknum]);
262 case NFPROTO_IPV6:
263 return rcu_dereference(net->nf.hooks_ipv6[hooknum]);
264 default:
265 WARN_ON_ONCE(1);
266 return NULL;
267 }
268
269 return NULL;
270}
271
272static int nf_ip_reroute(struct sk_buff *skb, const struct nf_queue_entry *entry)
273{
274#ifdef CONFIG_INET
275 const struct ip_rt_info *rt_info = nf_queue_entry_reroute(entry);
276
277 if (entry->state.hook == NF_INET_LOCAL_OUT) {
278 const struct iphdr *iph = ip_hdr(skb);
279
280 if (!(iph->tos == rt_info->tos &&
281 skb->mark == rt_info->mark &&
282 iph->daddr == rt_info->daddr &&
283 iph->saddr == rt_info->saddr))
284 return ip_route_me_harder(net: entry->state.net, sk: entry->state.sk,
285 skb, addr_type: RTN_UNSPEC);
286 }
287#endif
288 return 0;
289}
290
291static int nf_reroute(struct sk_buff *skb, struct nf_queue_entry *entry)
292{
293 const struct nf_ipv6_ops *v6ops;
294 int ret = 0;
295
296 switch (entry->state.pf) {
297 case AF_INET:
298 ret = nf_ip_reroute(skb, entry);
299 break;
300 case AF_INET6:
301 v6ops = rcu_dereference(nf_ipv6_ops);
302 if (v6ops)
303 ret = v6ops->reroute(skb, entry);
304 break;
305 }
306 return ret;
307}
308
309/* caller must hold rcu read-side lock */
310static void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
311{
312 const struct nf_hook_entry *hook_entry;
313 const struct nf_hook_entries *hooks;
314 struct sk_buff *skb = entry->skb;
315 const struct net *net;
316 unsigned int i;
317 int err;
318 u8 pf;
319
320 net = entry->state.net;
321 pf = entry->state.pf;
322
323 hooks = nf_hook_entries_head(net, pf, hooknum: entry->state.hook);
324
325 i = entry->hook_index;
326 if (WARN_ON_ONCE(!hooks || i >= hooks->num_hook_entries)) {
327 kfree_skb_reason(skb, reason: SKB_DROP_REASON_NETFILTER_DROP);
328 nf_queue_entry_free(entry);
329 return;
330 }
331
332 hook_entry = &hooks->hooks[i];
333
334 /* Continue traversal iff userspace said ok... */
335 if (verdict == NF_REPEAT)
336 verdict = nf_hook_entry_hookfn(entry: hook_entry, skb, state: &entry->state);
337
338 if (verdict == NF_ACCEPT) {
339 if (nf_reroute(skb, entry) < 0)
340 verdict = NF_DROP;
341 }
342
343 if (verdict == NF_ACCEPT) {
344next_hook:
345 ++i;
346 verdict = nf_iterate(skb, state: &entry->state, hooks, index: &i);
347 }
348
349 switch (verdict & NF_VERDICT_MASK) {
350 case NF_ACCEPT:
351 case NF_STOP:
352 local_bh_disable();
353 entry->state.okfn(entry->state.net, entry->state.sk, skb);
354 local_bh_enable();
355 break;
356 case NF_QUEUE:
357 err = nf_queue(skb, state: &entry->state, index: i, verdict);
358 if (err == 1)
359 goto next_hook;
360 break;
361 case NF_STOLEN:
362 break;
363 default:
364 kfree_skb(skb);
365 }
366
367 nf_queue_entry_free(entry);
368}
369
370static void nfqnl_reinject(struct nf_queue_entry *entry, unsigned int verdict)
371{
372 const struct nf_ct_hook *ct_hook;
373
374 if (verdict == NF_ACCEPT ||
375 verdict == NF_REPEAT ||
376 verdict == NF_STOP) {
377 unsigned int ct_verdict = verdict;
378
379 rcu_read_lock();
380 ct_hook = rcu_dereference(nf_ct_hook);
381 if (ct_hook)
382 ct_verdict = ct_hook->update(entry->state.net, entry->skb);
383 rcu_read_unlock();
384
385 switch (ct_verdict & NF_VERDICT_MASK) {
386 case NF_ACCEPT:
387 /* follow userspace verdict, could be REPEAT */
388 break;
389 case NF_STOLEN:
390 nf_queue_entry_free(entry);
391 return;
392 default:
393 verdict = ct_verdict & NF_VERDICT_MASK;
394 break;
395 }
396 }
397 nf_reinject(entry, verdict);
398}
399
400static void
401nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
402{
403 struct nf_queue_entry *entry, *next;
404
405 spin_lock_bh(lock: &queue->lock);
406 list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
407 if (!cmpfn || cmpfn(entry, data)) {
408 list_del(entry: &entry->list);
409 queue->queue_total--;
410 nfqnl_reinject(entry, NF_DROP);
411 }
412 }
413 spin_unlock_bh(lock: &queue->lock);
414}
415
416static int
417nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
418 bool csum_verify)
419{
420 __u32 flags = 0;
421
422 if (packet->ip_summed == CHECKSUM_PARTIAL)
423 flags = NFQA_SKB_CSUMNOTREADY;
424 else if (csum_verify)
425 flags = NFQA_SKB_CSUM_NOTVERIFIED;
426
427 if (skb_is_gso(skb: packet))
428 flags |= NFQA_SKB_GSO;
429
430 return flags ? nla_put_be32(skb: nlskb, attrtype: NFQA_SKB_INFO, htonl(flags)) : 0;
431}
432
433static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
434{
435 const struct cred *cred;
436
437 if (!sk_fullsock(sk))
438 return 0;
439
440 read_lock_bh(&sk->sk_callback_lock);
441 if (sk->sk_socket && sk->sk_socket->file) {
442 cred = sk->sk_socket->file->f_cred;
443 if (nla_put_be32(skb, attrtype: NFQA_UID,
444 htonl(from_kuid_munged(&init_user_ns, cred->fsuid))))
445 goto nla_put_failure;
446 if (nla_put_be32(skb, attrtype: NFQA_GID,
447 htonl(from_kgid_munged(&init_user_ns, cred->fsgid))))
448 goto nla_put_failure;
449 }
450 read_unlock_bh(&sk->sk_callback_lock);
451 return 0;
452
453nla_put_failure:
454 read_unlock_bh(&sk->sk_callback_lock);
455 return -1;
456}
457
458static int nfqnl_put_sk_classid(struct sk_buff *skb, struct sock *sk)
459{
460#if IS_ENABLED(CONFIG_CGROUP_NET_CLASSID)
461 if (sk && sk_fullsock(sk)) {
462 u32 classid = sock_cgroup_classid(skcd: &sk->sk_cgrp_data);
463
464 if (classid && nla_put_be32(skb, attrtype: NFQA_CGROUP_CLASSID, htonl(classid)))
465 return -1;
466 }
467#endif
468 return 0;
469}
470
471static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
472{
473 u32 seclen = 0;
474#if IS_ENABLED(CONFIG_NETWORK_SECMARK)
475 if (!skb || !sk_fullsock(sk: skb->sk))
476 return 0;
477
478 read_lock_bh(&skb->sk->sk_callback_lock);
479
480 if (skb->secmark)
481 security_secid_to_secctx(secid: skb->secmark, secdata, seclen: &seclen);
482
483 read_unlock_bh(&skb->sk->sk_callback_lock);
484#endif
485 return seclen;
486}
487
488static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
489{
490 struct sk_buff *entskb = entry->skb;
491 u32 nlalen = 0;
492
493 if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(skb: entskb))
494 return 0;
495
496 if (skb_vlan_tag_present(entskb))
497 nlalen += nla_total_size(payload: nla_total_size(payload: sizeof(__be16)) +
498 nla_total_size(payload: sizeof(__be16)));
499
500 if (entskb->network_header > entskb->mac_header)
501 nlalen += nla_total_size(payload: (entskb->network_header -
502 entskb->mac_header));
503
504 return nlalen;
505}
506
507static int nfqnl_put_bridge(struct nf_queue_entry *entry, struct sk_buff *skb)
508{
509 struct sk_buff *entskb = entry->skb;
510
511 if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(skb: entskb))
512 return 0;
513
514 if (skb_vlan_tag_present(entskb)) {
515 struct nlattr *nest;
516
517 nest = nla_nest_start(skb, attrtype: NFQA_VLAN);
518 if (!nest)
519 goto nla_put_failure;
520
521 if (nla_put_be16(skb, attrtype: NFQA_VLAN_TCI, htons(entskb->vlan_tci)) ||
522 nla_put_be16(skb, attrtype: NFQA_VLAN_PROTO, value: entskb->vlan_proto))
523 goto nla_put_failure;
524
525 nla_nest_end(skb, start: nest);
526 }
527
528 if (entskb->mac_header < entskb->network_header) {
529 int len = (int)(entskb->network_header - entskb->mac_header);
530
531 if (nla_put(skb, attrtype: NFQA_L2HDR, attrlen: len, data: skb_mac_header(skb: entskb)))
532 goto nla_put_failure;
533 }
534
535 return 0;
536
537nla_put_failure:
538 return -1;
539}
540
541static struct sk_buff *
542nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
543 struct nf_queue_entry *entry,
544 __be32 **packet_id_ptr)
545{
546 size_t size;
547 size_t data_len = 0, cap_len = 0;
548 unsigned int hlen = 0;
549 struct sk_buff *skb;
550 struct nlattr *nla;
551 struct nfqnl_msg_packet_hdr *pmsg;
552 struct nlmsghdr *nlh;
553 struct sk_buff *entskb = entry->skb;
554 struct net_device *indev;
555 struct net_device *outdev;
556 struct nf_conn *ct = NULL;
557 enum ip_conntrack_info ctinfo = 0;
558 const struct nfnl_ct_hook *nfnl_ct;
559 bool csum_verify;
560 char *secdata = NULL;
561 u32 seclen = 0;
562 ktime_t tstamp;
563
564 size = nlmsg_total_size(payload: sizeof(struct nfgenmsg))
565 + nla_total_size(payload: sizeof(struct nfqnl_msg_packet_hdr))
566 + nla_total_size(payload: sizeof(u_int32_t)) /* ifindex */
567 + nla_total_size(payload: sizeof(u_int32_t)) /* ifindex */
568#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
569 + nla_total_size(payload: sizeof(u_int32_t)) /* ifindex */
570 + nla_total_size(payload: sizeof(u_int32_t)) /* ifindex */
571#endif
572 + nla_total_size(payload: sizeof(u_int32_t)) /* mark */
573 + nla_total_size(payload: sizeof(u_int32_t)) /* priority */
574 + nla_total_size(payload: sizeof(struct nfqnl_msg_packet_hw))
575 + nla_total_size(payload: sizeof(u_int32_t)) /* skbinfo */
576#if IS_ENABLED(CONFIG_CGROUP_NET_CLASSID)
577 + nla_total_size(payload: sizeof(u_int32_t)) /* classid */
578#endif
579 + nla_total_size(payload: sizeof(u_int32_t)); /* cap_len */
580
581 tstamp = skb_tstamp_cond(skb: entskb, cond: false);
582 if (tstamp)
583 size += nla_total_size(payload: sizeof(struct nfqnl_msg_packet_timestamp));
584
585 size += nfqnl_get_bridge_size(entry);
586
587 if (entry->state.hook <= NF_INET_FORWARD ||
588 (entry->state.hook == NF_INET_POST_ROUTING && entskb->sk == NULL))
589 csum_verify = !skb_csum_unnecessary(skb: entskb);
590 else
591 csum_verify = false;
592
593 outdev = entry->state.out;
594
595 switch ((enum nfqnl_config_mode)READ_ONCE(queue->copy_mode)) {
596 case NFQNL_COPY_META:
597 case NFQNL_COPY_NONE:
598 break;
599
600 case NFQNL_COPY_PACKET:
601 if (!(queue->flags & NFQA_CFG_F_GSO) &&
602 entskb->ip_summed == CHECKSUM_PARTIAL &&
603 skb_checksum_help(skb: entskb))
604 return NULL;
605
606 data_len = READ_ONCE(queue->copy_range);
607 if (data_len > entskb->len)
608 data_len = entskb->len;
609
610 hlen = skb_zerocopy_headlen(from: entskb);
611 hlen = min_t(unsigned int, hlen, data_len);
612 size += sizeof(struct nlattr) + hlen;
613 cap_len = entskb->len;
614 break;
615 }
616
617 nfnl_ct = rcu_dereference(nfnl_ct_hook);
618
619#if IS_ENABLED(CONFIG_NF_CONNTRACK)
620 if (queue->flags & NFQA_CFG_F_CONNTRACK) {
621 if (nfnl_ct != NULL) {
622 ct = nf_ct_get(skb: entskb, ctinfo: &ctinfo);
623 if (ct != NULL)
624 size += nfnl_ct->build_size(ct);
625 }
626 }
627#endif
628
629 if (queue->flags & NFQA_CFG_F_UID_GID) {
630 size += (nla_total_size(payload: sizeof(u_int32_t)) /* uid */
631 + nla_total_size(payload: sizeof(u_int32_t))); /* gid */
632 }
633
634 if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
635 seclen = nfqnl_get_sk_secctx(skb: entskb, secdata: &secdata);
636 if (seclen)
637 size += nla_total_size(payload: seclen);
638 }
639
640 skb = alloc_skb(size, GFP_ATOMIC);
641 if (!skb) {
642 skb_tx_error(skb: entskb);
643 goto nlmsg_failure;
644 }
645
646 nlh = nfnl_msg_put(skb, portid: 0, seq: 0,
647 type: nfnl_msg_type(NFNL_SUBSYS_QUEUE, msg_type: NFQNL_MSG_PACKET),
648 flags: 0, family: entry->state.pf, NFNETLINK_V0,
649 htons(queue->queue_num));
650 if (!nlh) {
651 skb_tx_error(skb: entskb);
652 kfree_skb(skb);
653 goto nlmsg_failure;
654 }
655
656 nla = __nla_reserve(skb, attrtype: NFQA_PACKET_HDR, attrlen: sizeof(*pmsg));
657 pmsg = nla_data(nla);
658 pmsg->hw_protocol = entskb->protocol;
659 pmsg->hook = entry->state.hook;
660 *packet_id_ptr = &pmsg->packet_id;
661
662 indev = entry->state.in;
663 if (indev) {
664#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
665 if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
666 goto nla_put_failure;
667#else
668 if (entry->state.pf == PF_BRIDGE) {
669 /* Case 1: indev is physical input device, we need to
670 * look for bridge group (when called from
671 * netfilter_bridge) */
672 if (nla_put_be32(skb, attrtype: NFQA_IFINDEX_PHYSINDEV,
673 htonl(indev->ifindex)) ||
674 /* this is the bridge group "brX" */
675 /* rcu_read_lock()ed by __nf_queue */
676 nla_put_be32(skb, attrtype: NFQA_IFINDEX_INDEV,
677 htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
678 goto nla_put_failure;
679 } else {
680 int physinif;
681
682 /* Case 2: indev is bridge group, we need to look for
683 * physical device (when called from ipv4) */
684 if (nla_put_be32(skb, attrtype: NFQA_IFINDEX_INDEV,
685 htonl(indev->ifindex)))
686 goto nla_put_failure;
687
688 physinif = nf_bridge_get_physinif(skb: entskb);
689 if (physinif &&
690 nla_put_be32(skb, attrtype: NFQA_IFINDEX_PHYSINDEV,
691 htonl(physinif)))
692 goto nla_put_failure;
693 }
694#endif
695 }
696
697 if (outdev) {
698#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
699 if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
700 goto nla_put_failure;
701#else
702 if (entry->state.pf == PF_BRIDGE) {
703 /* Case 1: outdev is physical output device, we need to
704 * look for bridge group (when called from
705 * netfilter_bridge) */
706 if (nla_put_be32(skb, attrtype: NFQA_IFINDEX_PHYSOUTDEV,
707 htonl(outdev->ifindex)) ||
708 /* this is the bridge group "brX" */
709 /* rcu_read_lock()ed by __nf_queue */
710 nla_put_be32(skb, attrtype: NFQA_IFINDEX_OUTDEV,
711 htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
712 goto nla_put_failure;
713 } else {
714 int physoutif;
715
716 /* Case 2: outdev is bridge group, we need to look for
717 * physical output device (when called from ipv4) */
718 if (nla_put_be32(skb, attrtype: NFQA_IFINDEX_OUTDEV,
719 htonl(outdev->ifindex)))
720 goto nla_put_failure;
721
722 physoutif = nf_bridge_get_physoutif(skb: entskb);
723 if (physoutif &&
724 nla_put_be32(skb, attrtype: NFQA_IFINDEX_PHYSOUTDEV,
725 htonl(physoutif)))
726 goto nla_put_failure;
727 }
728#endif
729 }
730
731 if (entskb->mark &&
732 nla_put_be32(skb, attrtype: NFQA_MARK, htonl(entskb->mark)))
733 goto nla_put_failure;
734
735 if (entskb->priority &&
736 nla_put_be32(skb, attrtype: NFQA_PRIORITY, htonl(entskb->priority)))
737 goto nla_put_failure;
738
739 if (indev && entskb->dev &&
740 skb_mac_header_was_set(skb: entskb) &&
741 skb_mac_header_len(skb: entskb) != 0) {
742 struct nfqnl_msg_packet_hw phw;
743 int len;
744
745 memset(&phw, 0, sizeof(phw));
746 len = dev_parse_header(skb: entskb, haddr: phw.hw_addr);
747 if (len) {
748 phw.hw_addrlen = htons(len);
749 if (nla_put(skb, attrtype: NFQA_HWADDR, attrlen: sizeof(phw), data: &phw))
750 goto nla_put_failure;
751 }
752 }
753
754 if (nfqnl_put_bridge(entry, skb) < 0)
755 goto nla_put_failure;
756
757 if (entry->state.hook <= NF_INET_FORWARD && tstamp) {
758 struct nfqnl_msg_packet_timestamp ts;
759 struct timespec64 kts = ktime_to_timespec64(tstamp);
760
761 ts.sec = cpu_to_be64(kts.tv_sec);
762 ts.usec = cpu_to_be64(kts.tv_nsec / NSEC_PER_USEC);
763
764 if (nla_put(skb, attrtype: NFQA_TIMESTAMP, attrlen: sizeof(ts), data: &ts))
765 goto nla_put_failure;
766 }
767
768 if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk &&
769 nfqnl_put_sk_uidgid(skb, sk: entskb->sk) < 0)
770 goto nla_put_failure;
771
772 if (nfqnl_put_sk_classid(skb, sk: entskb->sk) < 0)
773 goto nla_put_failure;
774
775 if (seclen && nla_put(skb, attrtype: NFQA_SECCTX, attrlen: seclen, data: secdata))
776 goto nla_put_failure;
777
778 if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
779 goto nla_put_failure;
780
781 if (cap_len > data_len &&
782 nla_put_be32(skb, attrtype: NFQA_CAP_LEN, htonl(cap_len)))
783 goto nla_put_failure;
784
785 if (nfqnl_put_packet_info(nlskb: skb, packet: entskb, csum_verify))
786 goto nla_put_failure;
787
788 if (data_len) {
789 struct nlattr *nla;
790
791 if (skb_tailroom(skb) < sizeof(*nla) + hlen)
792 goto nla_put_failure;
793
794 nla = skb_put(skb, len: sizeof(*nla));
795 nla->nla_type = NFQA_PAYLOAD;
796 nla->nla_len = nla_attr_size(payload: data_len);
797
798 if (skb_zerocopy(to: skb, from: entskb, len: data_len, hlen))
799 goto nla_put_failure;
800 }
801
802 nlh->nlmsg_len = skb->len;
803 if (seclen)
804 security_release_secctx(secdata, seclen);
805 return skb;
806
807nla_put_failure:
808 skb_tx_error(skb: entskb);
809 kfree_skb(skb);
810 net_err_ratelimited("nf_queue: error creating packet message\n");
811nlmsg_failure:
812 if (seclen)
813 security_release_secctx(secdata, seclen);
814 return NULL;
815}
816
817static bool nf_ct_drop_unconfirmed(const struct nf_queue_entry *entry)
818{
819#if IS_ENABLED(CONFIG_NF_CONNTRACK)
820 static const unsigned long flags = IPS_CONFIRMED | IPS_DYING;
821 const struct nf_conn *ct = (void *)skb_nfct(skb: entry->skb);
822
823 if (ct && ((ct->status & flags) == IPS_DYING))
824 return true;
825#endif
826 return false;
827}
828
829static int
830__nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue,
831 struct nf_queue_entry *entry)
832{
833 struct sk_buff *nskb;
834 int err = -ENOBUFS;
835 __be32 *packet_id_ptr;
836 int failopen = 0;
837
838 nskb = nfqnl_build_packet_message(net, queue, entry, packet_id_ptr: &packet_id_ptr);
839 if (nskb == NULL) {
840 err = -ENOMEM;
841 goto err_out;
842 }
843 spin_lock_bh(lock: &queue->lock);
844
845 if (nf_ct_drop_unconfirmed(entry))
846 goto err_out_free_nskb;
847
848 if (queue->queue_total >= queue->queue_maxlen) {
849 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
850 failopen = 1;
851 err = 0;
852 } else {
853 queue->queue_dropped++;
854 net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
855 queue->queue_total);
856 }
857 goto err_out_free_nskb;
858 }
859 entry->id = ++queue->id_sequence;
860 *packet_id_ptr = htonl(entry->id);
861
862 /* nfnetlink_unicast will either free the nskb or add it to a socket */
863 err = nfnetlink_unicast(skb: nskb, net, portid: queue->peer_portid);
864 if (err < 0) {
865 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
866 failopen = 1;
867 err = 0;
868 } else {
869 queue->queue_user_dropped++;
870 }
871 goto err_out_unlock;
872 }
873
874 __enqueue_entry(queue, entry);
875
876 spin_unlock_bh(lock: &queue->lock);
877 return 0;
878
879err_out_free_nskb:
880 kfree_skb(skb: nskb);
881err_out_unlock:
882 spin_unlock_bh(lock: &queue->lock);
883 if (failopen)
884 nfqnl_reinject(entry, NF_ACCEPT);
885err_out:
886 return err;
887}
888
889static struct nf_queue_entry *
890nf_queue_entry_dup(struct nf_queue_entry *e)
891{
892 struct nf_queue_entry *entry = kmemdup(p: e, size: e->size, GFP_ATOMIC);
893
894 if (!entry)
895 return NULL;
896
897 if (nf_queue_entry_get_refs(entry))
898 return entry;
899
900 kfree(objp: entry);
901 return NULL;
902}
903
904#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
905/* When called from bridge netfilter, skb->data must point to MAC header
906 * before calling skb_gso_segment(). Else, original MAC header is lost
907 * and segmented skbs will be sent to wrong destination.
908 */
909static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
910{
911 if (nf_bridge_info_get(skb))
912 __skb_push(skb, len: skb->network_header - skb->mac_header);
913}
914
915static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
916{
917 if (nf_bridge_info_get(skb))
918 __skb_pull(skb, len: skb->network_header - skb->mac_header);
919}
920#else
921#define nf_bridge_adjust_skb_data(s) do {} while (0)
922#define nf_bridge_adjust_segmented_data(s) do {} while (0)
923#endif
924
925static int
926__nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue,
927 struct sk_buff *skb, struct nf_queue_entry *entry)
928{
929 int ret = -ENOMEM;
930 struct nf_queue_entry *entry_seg;
931
932 nf_bridge_adjust_segmented_data(skb);
933
934 if (skb->next == NULL) { /* last packet, no need to copy entry */
935 struct sk_buff *gso_skb = entry->skb;
936 entry->skb = skb;
937 ret = __nfqnl_enqueue_packet(net, queue, entry);
938 if (ret)
939 entry->skb = gso_skb;
940 return ret;
941 }
942
943 skb_mark_not_on_list(skb);
944
945 entry_seg = nf_queue_entry_dup(e: entry);
946 if (entry_seg) {
947 entry_seg->skb = skb;
948 ret = __nfqnl_enqueue_packet(net, queue, entry: entry_seg);
949 if (ret)
950 nf_queue_entry_free(entry: entry_seg);
951 }
952 return ret;
953}
954
955static int
956nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
957{
958 unsigned int queued;
959 struct nfqnl_instance *queue;
960 struct sk_buff *skb, *segs, *nskb;
961 int err = -ENOBUFS;
962 struct net *net = entry->state.net;
963 struct nfnl_queue_net *q = nfnl_queue_pernet(net);
964
965 /* rcu_read_lock()ed by nf_hook_thresh */
966 queue = instance_lookup(q, queue_num: queuenum);
967 if (!queue)
968 return -ESRCH;
969
970 if (queue->copy_mode == NFQNL_COPY_NONE)
971 return -EINVAL;
972
973 skb = entry->skb;
974
975 switch (entry->state.pf) {
976 case NFPROTO_IPV4:
977 skb->protocol = htons(ETH_P_IP);
978 break;
979 case NFPROTO_IPV6:
980 skb->protocol = htons(ETH_P_IPV6);
981 break;
982 }
983
984 if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb))
985 return __nfqnl_enqueue_packet(net, queue, entry);
986
987 nf_bridge_adjust_skb_data(skb);
988 segs = skb_gso_segment(skb, features: 0);
989 /* Does not use PTR_ERR to limit the number of error codes that can be
990 * returned by nf_queue. For instance, callers rely on -ESRCH to
991 * mean 'ignore this hook'.
992 */
993 if (IS_ERR_OR_NULL(ptr: segs))
994 goto out_err;
995 queued = 0;
996 err = 0;
997 skb_list_walk_safe(segs, segs, nskb) {
998 if (err == 0)
999 err = __nfqnl_enqueue_packet_gso(net, queue,
1000 skb: segs, entry);
1001 if (err == 0)
1002 queued++;
1003 else
1004 kfree_skb(skb: segs);
1005 }
1006
1007 if (queued) {
1008 if (err) /* some segments are already queued */
1009 nf_queue_entry_free(entry);
1010 kfree_skb(skb);
1011 return 0;
1012 }
1013 out_err:
1014 nf_bridge_adjust_segmented_data(skb);
1015 return err;
1016}
1017
1018static int
1019nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int diff)
1020{
1021 struct sk_buff *nskb;
1022
1023 if (diff < 0) {
1024 unsigned int min_len = skb_transport_offset(skb: e->skb);
1025
1026 if (data_len < min_len)
1027 return -EINVAL;
1028
1029 if (pskb_trim(skb: e->skb, len: data_len))
1030 return -ENOMEM;
1031 } else if (diff > 0) {
1032 if (data_len > 0xFFFF)
1033 return -EINVAL;
1034 if (diff > skb_tailroom(skb: e->skb)) {
1035 nskb = skb_copy_expand(skb: e->skb, newheadroom: skb_headroom(skb: e->skb),
1036 newtailroom: diff, GFP_ATOMIC);
1037 if (!nskb)
1038 return -ENOMEM;
1039 kfree_skb(skb: e->skb);
1040 e->skb = nskb;
1041 }
1042 skb_put(skb: e->skb, len: diff);
1043 }
1044 if (skb_ensure_writable(skb: e->skb, write_len: data_len))
1045 return -ENOMEM;
1046 skb_copy_to_linear_data(skb: e->skb, from: data, len: data_len);
1047 e->skb->ip_summed = CHECKSUM_NONE;
1048 return 0;
1049}
1050
1051static int
1052nfqnl_set_mode(struct nfqnl_instance *queue,
1053 unsigned char mode, unsigned int range)
1054{
1055 int status = 0;
1056
1057 spin_lock_bh(lock: &queue->lock);
1058 switch (mode) {
1059 case NFQNL_COPY_NONE:
1060 case NFQNL_COPY_META:
1061 queue->copy_mode = mode;
1062 queue->copy_range = 0;
1063 break;
1064
1065 case NFQNL_COPY_PACKET:
1066 queue->copy_mode = mode;
1067 if (range == 0 || range > NFQNL_MAX_COPY_RANGE)
1068 queue->copy_range = NFQNL_MAX_COPY_RANGE;
1069 else
1070 queue->copy_range = range;
1071 break;
1072
1073 default:
1074 status = -EINVAL;
1075
1076 }
1077 spin_unlock_bh(lock: &queue->lock);
1078
1079 return status;
1080}
1081
1082static int
1083dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
1084{
1085#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
1086 int physinif, physoutif;
1087
1088 physinif = nf_bridge_get_physinif(skb: entry->skb);
1089 physoutif = nf_bridge_get_physoutif(skb: entry->skb);
1090
1091 if (physinif == ifindex || physoutif == ifindex)
1092 return 1;
1093#endif
1094 if (entry->state.in)
1095 if (entry->state.in->ifindex == ifindex)
1096 return 1;
1097 if (entry->state.out)
1098 if (entry->state.out->ifindex == ifindex)
1099 return 1;
1100
1101 return 0;
1102}
1103
1104/* drop all packets with either indev or outdev == ifindex from all queue
1105 * instances */
1106static void
1107nfqnl_dev_drop(struct net *net, int ifindex)
1108{
1109 int i;
1110 struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1111
1112 rcu_read_lock();
1113
1114 for (i = 0; i < INSTANCE_BUCKETS; i++) {
1115 struct nfqnl_instance *inst;
1116 struct hlist_head *head = &q->instance_table[i];
1117
1118 hlist_for_each_entry_rcu(inst, head, hlist)
1119 nfqnl_flush(queue: inst, cmpfn: dev_cmp, data: ifindex);
1120 }
1121
1122 rcu_read_unlock();
1123}
1124
1125static int
1126nfqnl_rcv_dev_event(struct notifier_block *this,
1127 unsigned long event, void *ptr)
1128{
1129 struct net_device *dev = netdev_notifier_info_to_dev(info: ptr);
1130
1131 /* Drop any packets associated with the downed device */
1132 if (event == NETDEV_DOWN)
1133 nfqnl_dev_drop(net: dev_net(dev), ifindex: dev->ifindex);
1134 return NOTIFY_DONE;
1135}
1136
1137static struct notifier_block nfqnl_dev_notifier = {
1138 .notifier_call = nfqnl_rcv_dev_event,
1139};
1140
1141static void nfqnl_nf_hook_drop(struct net *net)
1142{
1143 struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1144 int i;
1145
1146 /* This function is also called on net namespace error unwind,
1147 * when pernet_ops->init() failed and ->exit() functions of the
1148 * previous pernet_ops gets called.
1149 *
1150 * This may result in a call to nfqnl_nf_hook_drop() before
1151 * struct nfnl_queue_net was allocated.
1152 */
1153 if (!q)
1154 return;
1155
1156 for (i = 0; i < INSTANCE_BUCKETS; i++) {
1157 struct nfqnl_instance *inst;
1158 struct hlist_head *head = &q->instance_table[i];
1159
1160 hlist_for_each_entry_rcu(inst, head, hlist)
1161 nfqnl_flush(queue: inst, NULL, data: 0);
1162 }
1163}
1164
1165static int
1166nfqnl_rcv_nl_event(struct notifier_block *this,
1167 unsigned long event, void *ptr)
1168{
1169 struct netlink_notify *n = ptr;
1170 struct nfnl_queue_net *q = nfnl_queue_pernet(net: n->net);
1171
1172 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
1173 int i;
1174
1175 /* destroy all instances for this portid */
1176 spin_lock(lock: &q->instances_lock);
1177 for (i = 0; i < INSTANCE_BUCKETS; i++) {
1178 struct hlist_node *t2;
1179 struct nfqnl_instance *inst;
1180 struct hlist_head *head = &q->instance_table[i];
1181
1182 hlist_for_each_entry_safe(inst, t2, head, hlist) {
1183 if (n->portid == inst->peer_portid)
1184 __instance_destroy(inst);
1185 }
1186 }
1187 spin_unlock(lock: &q->instances_lock);
1188 }
1189 return NOTIFY_DONE;
1190}
1191
1192static struct notifier_block nfqnl_rtnl_notifier = {
1193 .notifier_call = nfqnl_rcv_nl_event,
1194};
1195
1196static const struct nla_policy nfqa_vlan_policy[NFQA_VLAN_MAX + 1] = {
1197 [NFQA_VLAN_TCI] = { .type = NLA_U16},
1198 [NFQA_VLAN_PROTO] = { .type = NLA_U16},
1199};
1200
1201static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
1202 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
1203 [NFQA_MARK] = { .type = NLA_U32 },
1204 [NFQA_PAYLOAD] = { .type = NLA_UNSPEC },
1205 [NFQA_CT] = { .type = NLA_UNSPEC },
1206 [NFQA_EXP] = { .type = NLA_UNSPEC },
1207 [NFQA_VLAN] = { .type = NLA_NESTED },
1208 [NFQA_PRIORITY] = { .type = NLA_U32 },
1209};
1210
1211static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
1212 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
1213 [NFQA_MARK] = { .type = NLA_U32 },
1214 [NFQA_PRIORITY] = { .type = NLA_U32 },
1215};
1216
1217static struct nfqnl_instance *
1218verdict_instance_lookup(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid)
1219{
1220 struct nfqnl_instance *queue;
1221
1222 queue = instance_lookup(q, queue_num);
1223 if (!queue)
1224 return ERR_PTR(error: -ENODEV);
1225
1226 if (queue->peer_portid != nlportid)
1227 return ERR_PTR(error: -EPERM);
1228
1229 return queue;
1230}
1231
1232static struct nfqnl_msg_verdict_hdr*
1233verdicthdr_get(const struct nlattr * const nfqa[])
1234{
1235 struct nfqnl_msg_verdict_hdr *vhdr;
1236 unsigned int verdict;
1237
1238 if (!nfqa[NFQA_VERDICT_HDR])
1239 return NULL;
1240
1241 vhdr = nla_data(nla: nfqa[NFQA_VERDICT_HDR]);
1242 verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
1243 if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
1244 return NULL;
1245 return vhdr;
1246}
1247
1248static int nfq_id_after(unsigned int id, unsigned int max)
1249{
1250 return (int)(id - max) > 0;
1251}
1252
1253static int nfqnl_recv_verdict_batch(struct sk_buff *skb,
1254 const struct nfnl_info *info,
1255 const struct nlattr * const nfqa[])
1256{
1257 struct nfnl_queue_net *q = nfnl_queue_pernet(net: info->net);
1258 u16 queue_num = ntohs(info->nfmsg->res_id);
1259 struct nf_queue_entry *entry, *tmp;
1260 struct nfqnl_msg_verdict_hdr *vhdr;
1261 struct nfqnl_instance *queue;
1262 unsigned int verdict, maxid;
1263 LIST_HEAD(batch_list);
1264
1265 queue = verdict_instance_lookup(q, queue_num,
1266 NETLINK_CB(skb).portid);
1267 if (IS_ERR(ptr: queue))
1268 return PTR_ERR(ptr: queue);
1269
1270 vhdr = verdicthdr_get(nfqa);
1271 if (!vhdr)
1272 return -EINVAL;
1273
1274 verdict = ntohl(vhdr->verdict);
1275 maxid = ntohl(vhdr->id);
1276
1277 spin_lock_bh(lock: &queue->lock);
1278
1279 list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
1280 if (nfq_id_after(id: entry->id, max: maxid))
1281 break;
1282 __dequeue_entry(queue, entry);
1283 list_add_tail(new: &entry->list, head: &batch_list);
1284 }
1285
1286 spin_unlock_bh(lock: &queue->lock);
1287
1288 if (list_empty(head: &batch_list))
1289 return -ENOENT;
1290
1291 list_for_each_entry_safe(entry, tmp, &batch_list, list) {
1292 if (nfqa[NFQA_MARK])
1293 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1294
1295 if (nfqa[NFQA_PRIORITY])
1296 entry->skb->priority = ntohl(nla_get_be32(nfqa[NFQA_PRIORITY]));
1297
1298 nfqnl_reinject(entry, verdict);
1299 }
1300 return 0;
1301}
1302
1303static struct nf_conn *nfqnl_ct_parse(const struct nfnl_ct_hook *nfnl_ct,
1304 const struct nlmsghdr *nlh,
1305 const struct nlattr * const nfqa[],
1306 struct nf_queue_entry *entry,
1307 enum ip_conntrack_info *ctinfo)
1308{
1309#if IS_ENABLED(CONFIG_NF_CONNTRACK)
1310 struct nf_conn *ct;
1311
1312 ct = nf_ct_get(skb: entry->skb, ctinfo);
1313 if (ct == NULL)
1314 return NULL;
1315
1316 if (nfnl_ct->parse(nfqa[NFQA_CT], ct) < 0)
1317 return NULL;
1318
1319 if (nfqa[NFQA_EXP])
1320 nfnl_ct->attach_expect(nfqa[NFQA_EXP], ct,
1321 NETLINK_CB(entry->skb).portid,
1322 nlmsg_report(nlh));
1323 return ct;
1324#else
1325 return NULL;
1326#endif
1327}
1328
1329static int nfqa_parse_bridge(struct nf_queue_entry *entry,
1330 const struct nlattr * const nfqa[])
1331{
1332 if (nfqa[NFQA_VLAN]) {
1333 struct nlattr *tb[NFQA_VLAN_MAX + 1];
1334 int err;
1335
1336 err = nla_parse_nested_deprecated(tb, NFQA_VLAN_MAX,
1337 nla: nfqa[NFQA_VLAN],
1338 policy: nfqa_vlan_policy, NULL);
1339 if (err < 0)
1340 return err;
1341
1342 if (!tb[NFQA_VLAN_TCI] || !tb[NFQA_VLAN_PROTO])
1343 return -EINVAL;
1344
1345 __vlan_hwaccel_put_tag(skb: entry->skb,
1346 vlan_proto: nla_get_be16(nla: tb[NFQA_VLAN_PROTO]),
1347 ntohs(nla_get_be16(tb[NFQA_VLAN_TCI])));
1348 }
1349
1350 if (nfqa[NFQA_L2HDR]) {
1351 int mac_header_len = entry->skb->network_header -
1352 entry->skb->mac_header;
1353
1354 if (mac_header_len != nla_len(nla: nfqa[NFQA_L2HDR]))
1355 return -EINVAL;
1356 else if (mac_header_len > 0)
1357 memcpy(skb_mac_header(entry->skb),
1358 nla_data(nfqa[NFQA_L2HDR]),
1359 mac_header_len);
1360 }
1361
1362 return 0;
1363}
1364
1365static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info,
1366 const struct nlattr * const nfqa[])
1367{
1368 struct nfnl_queue_net *q = nfnl_queue_pernet(net: info->net);
1369 u_int16_t queue_num = ntohs(info->nfmsg->res_id);
1370 const struct nfnl_ct_hook *nfnl_ct;
1371 struct nfqnl_msg_verdict_hdr *vhdr;
1372 enum ip_conntrack_info ctinfo;
1373 struct nfqnl_instance *queue;
1374 struct nf_queue_entry *entry;
1375 struct nf_conn *ct = NULL;
1376 unsigned int verdict;
1377 int err;
1378
1379 queue = verdict_instance_lookup(q, queue_num,
1380 NETLINK_CB(skb).portid);
1381 if (IS_ERR(ptr: queue))
1382 return PTR_ERR(ptr: queue);
1383
1384 vhdr = verdicthdr_get(nfqa);
1385 if (!vhdr)
1386 return -EINVAL;
1387
1388 verdict = ntohl(vhdr->verdict);
1389
1390 entry = find_dequeue_entry(queue, ntohl(vhdr->id));
1391 if (entry == NULL)
1392 return -ENOENT;
1393
1394 /* rcu lock already held from nfnl->call_rcu. */
1395 nfnl_ct = rcu_dereference(nfnl_ct_hook);
1396
1397 if (nfqa[NFQA_CT]) {
1398 if (nfnl_ct != NULL)
1399 ct = nfqnl_ct_parse(nfnl_ct, nlh: info->nlh, nfqa, entry,
1400 ctinfo: &ctinfo);
1401 }
1402
1403 if (entry->state.pf == PF_BRIDGE) {
1404 err = nfqa_parse_bridge(entry, nfqa);
1405 if (err < 0)
1406 return err;
1407 }
1408
1409 if (nfqa[NFQA_PAYLOAD]) {
1410 u16 payload_len = nla_len(nla: nfqa[NFQA_PAYLOAD]);
1411 int diff = payload_len - entry->skb->len;
1412
1413 if (nfqnl_mangle(data: nla_data(nla: nfqa[NFQA_PAYLOAD]),
1414 data_len: payload_len, e: entry, diff) < 0)
1415 verdict = NF_DROP;
1416
1417 if (ct && diff)
1418 nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff);
1419 }
1420
1421 if (nfqa[NFQA_MARK])
1422 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1423
1424 if (nfqa[NFQA_PRIORITY])
1425 entry->skb->priority = ntohl(nla_get_be32(nfqa[NFQA_PRIORITY]));
1426
1427 nfqnl_reinject(entry, verdict);
1428 return 0;
1429}
1430
1431static int nfqnl_recv_unsupp(struct sk_buff *skb, const struct nfnl_info *info,
1432 const struct nlattr * const cda[])
1433{
1434 return -ENOTSUPP;
1435}
1436
1437static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
1438 [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) },
1439 [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) },
1440 [NFQA_CFG_QUEUE_MAXLEN] = { .type = NLA_U32 },
1441 [NFQA_CFG_MASK] = { .type = NLA_U32 },
1442 [NFQA_CFG_FLAGS] = { .type = NLA_U32 },
1443};
1444
1445static const struct nf_queue_handler nfqh = {
1446 .outfn = nfqnl_enqueue_packet,
1447 .nf_hook_drop = nfqnl_nf_hook_drop,
1448};
1449
1450static int nfqnl_recv_config(struct sk_buff *skb, const struct nfnl_info *info,
1451 const struct nlattr * const nfqa[])
1452{
1453 struct nfnl_queue_net *q = nfnl_queue_pernet(net: info->net);
1454 u_int16_t queue_num = ntohs(info->nfmsg->res_id);
1455 struct nfqnl_msg_config_cmd *cmd = NULL;
1456 struct nfqnl_instance *queue;
1457 __u32 flags = 0, mask = 0;
1458 int ret = 0;
1459
1460 if (nfqa[NFQA_CFG_CMD]) {
1461 cmd = nla_data(nla: nfqa[NFQA_CFG_CMD]);
1462
1463 /* Obsolete commands without queue context */
1464 switch (cmd->command) {
1465 case NFQNL_CFG_CMD_PF_BIND: return 0;
1466 case NFQNL_CFG_CMD_PF_UNBIND: return 0;
1467 }
1468 }
1469
1470 /* Check if we support these flags in first place, dependencies should
1471 * be there too not to break atomicity.
1472 */
1473 if (nfqa[NFQA_CFG_FLAGS]) {
1474 if (!nfqa[NFQA_CFG_MASK]) {
1475 /* A mask is needed to specify which flags are being
1476 * changed.
1477 */
1478 return -EINVAL;
1479 }
1480
1481 flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
1482 mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
1483
1484 if (flags >= NFQA_CFG_F_MAX)
1485 return -EOPNOTSUPP;
1486
1487#if !IS_ENABLED(CONFIG_NETWORK_SECMARK)
1488 if (flags & mask & NFQA_CFG_F_SECCTX)
1489 return -EOPNOTSUPP;
1490#endif
1491 if ((flags & mask & NFQA_CFG_F_CONNTRACK) &&
1492 !rcu_access_pointer(nfnl_ct_hook)) {
1493#ifdef CONFIG_MODULES
1494 nfnl_unlock(NFNL_SUBSYS_QUEUE);
1495 request_module("ip_conntrack_netlink");
1496 nfnl_lock(NFNL_SUBSYS_QUEUE);
1497 if (rcu_access_pointer(nfnl_ct_hook))
1498 return -EAGAIN;
1499#endif
1500 return -EOPNOTSUPP;
1501 }
1502 }
1503
1504 rcu_read_lock();
1505 queue = instance_lookup(q, queue_num);
1506 if (queue && queue->peer_portid != NETLINK_CB(skb).portid) {
1507 ret = -EPERM;
1508 goto err_out_unlock;
1509 }
1510
1511 if (cmd != NULL) {
1512 switch (cmd->command) {
1513 case NFQNL_CFG_CMD_BIND:
1514 if (queue) {
1515 ret = -EBUSY;
1516 goto err_out_unlock;
1517 }
1518 queue = instance_create(q, queue_num,
1519 NETLINK_CB(skb).portid);
1520 if (IS_ERR(ptr: queue)) {
1521 ret = PTR_ERR(ptr: queue);
1522 goto err_out_unlock;
1523 }
1524 break;
1525 case NFQNL_CFG_CMD_UNBIND:
1526 if (!queue) {
1527 ret = -ENODEV;
1528 goto err_out_unlock;
1529 }
1530 instance_destroy(q, inst: queue);
1531 goto err_out_unlock;
1532 case NFQNL_CFG_CMD_PF_BIND:
1533 case NFQNL_CFG_CMD_PF_UNBIND:
1534 break;
1535 default:
1536 ret = -ENOTSUPP;
1537 goto err_out_unlock;
1538 }
1539 }
1540
1541 if (!queue) {
1542 ret = -ENODEV;
1543 goto err_out_unlock;
1544 }
1545
1546 if (nfqa[NFQA_CFG_PARAMS]) {
1547 struct nfqnl_msg_config_params *params =
1548 nla_data(nla: nfqa[NFQA_CFG_PARAMS]);
1549
1550 nfqnl_set_mode(queue, mode: params->copy_mode,
1551 ntohl(params->copy_range));
1552 }
1553
1554 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
1555 __be32 *queue_maxlen = nla_data(nla: nfqa[NFQA_CFG_QUEUE_MAXLEN]);
1556
1557 spin_lock_bh(lock: &queue->lock);
1558 queue->queue_maxlen = ntohl(*queue_maxlen);
1559 spin_unlock_bh(lock: &queue->lock);
1560 }
1561
1562 if (nfqa[NFQA_CFG_FLAGS]) {
1563 spin_lock_bh(lock: &queue->lock);
1564 queue->flags &= ~mask;
1565 queue->flags |= flags & mask;
1566 spin_unlock_bh(lock: &queue->lock);
1567 }
1568
1569err_out_unlock:
1570 rcu_read_unlock();
1571 return ret;
1572}
1573
1574static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
1575 [NFQNL_MSG_PACKET] = {
1576 .call = nfqnl_recv_unsupp,
1577 .type = NFNL_CB_RCU,
1578 .attr_count = NFQA_MAX,
1579 },
1580 [NFQNL_MSG_VERDICT] = {
1581 .call = nfqnl_recv_verdict,
1582 .type = NFNL_CB_RCU,
1583 .attr_count = NFQA_MAX,
1584 .policy = nfqa_verdict_policy
1585 },
1586 [NFQNL_MSG_CONFIG] = {
1587 .call = nfqnl_recv_config,
1588 .type = NFNL_CB_MUTEX,
1589 .attr_count = NFQA_CFG_MAX,
1590 .policy = nfqa_cfg_policy
1591 },
1592 [NFQNL_MSG_VERDICT_BATCH] = {
1593 .call = nfqnl_recv_verdict_batch,
1594 .type = NFNL_CB_RCU,
1595 .attr_count = NFQA_MAX,
1596 .policy = nfqa_verdict_batch_policy
1597 },
1598};
1599
1600static const struct nfnetlink_subsystem nfqnl_subsys = {
1601 .name = "nf_queue",
1602 .subsys_id = NFNL_SUBSYS_QUEUE,
1603 .cb_count = NFQNL_MSG_MAX,
1604 .cb = nfqnl_cb,
1605};
1606
1607#ifdef CONFIG_PROC_FS
1608struct iter_state {
1609 struct seq_net_private p;
1610 unsigned int bucket;
1611};
1612
1613static struct hlist_node *get_first(struct seq_file *seq)
1614{
1615 struct iter_state *st = seq->private;
1616 struct net *net;
1617 struct nfnl_queue_net *q;
1618
1619 if (!st)
1620 return NULL;
1621
1622 net = seq_file_net(seq);
1623 q = nfnl_queue_pernet(net);
1624 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
1625 if (!hlist_empty(h: &q->instance_table[st->bucket]))
1626 return q->instance_table[st->bucket].first;
1627 }
1628 return NULL;
1629}
1630
1631static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
1632{
1633 struct iter_state *st = seq->private;
1634 struct net *net = seq_file_net(seq);
1635
1636 h = h->next;
1637 while (!h) {
1638 struct nfnl_queue_net *q;
1639
1640 if (++st->bucket >= INSTANCE_BUCKETS)
1641 return NULL;
1642
1643 q = nfnl_queue_pernet(net);
1644 h = q->instance_table[st->bucket].first;
1645 }
1646 return h;
1647}
1648
1649static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
1650{
1651 struct hlist_node *head;
1652 head = get_first(seq);
1653
1654 if (head)
1655 while (pos && (head = get_next(seq, h: head)))
1656 pos--;
1657 return pos ? NULL : head;
1658}
1659
1660static void *seq_start(struct seq_file *s, loff_t *pos)
1661 __acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1662{
1663 spin_lock(lock: &nfnl_queue_pernet(net: seq_file_net(seq: s))->instances_lock);
1664 return get_idx(seq: s, pos: *pos);
1665}
1666
1667static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
1668{
1669 (*pos)++;
1670 return get_next(seq: s, h: v);
1671}
1672
1673static void seq_stop(struct seq_file *s, void *v)
1674 __releases(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1675{
1676 spin_unlock(lock: &nfnl_queue_pernet(net: seq_file_net(seq: s))->instances_lock);
1677}
1678
1679static int seq_show(struct seq_file *s, void *v)
1680{
1681 const struct nfqnl_instance *inst = v;
1682
1683 seq_printf(m: s, fmt: "%5u %6u %5u %1u %5u %5u %5u %8u %2d\n",
1684 inst->queue_num,
1685 inst->peer_portid, inst->queue_total,
1686 inst->copy_mode, inst->copy_range,
1687 inst->queue_dropped, inst->queue_user_dropped,
1688 inst->id_sequence, 1);
1689 return 0;
1690}
1691
1692static const struct seq_operations nfqnl_seq_ops = {
1693 .start = seq_start,
1694 .next = seq_next,
1695 .stop = seq_stop,
1696 .show = seq_show,
1697};
1698#endif /* PROC_FS */
1699
1700static int __net_init nfnl_queue_net_init(struct net *net)
1701{
1702 unsigned int i;
1703 struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1704
1705 for (i = 0; i < INSTANCE_BUCKETS; i++)
1706 INIT_HLIST_HEAD(&q->instance_table[i]);
1707
1708 spin_lock_init(&q->instances_lock);
1709
1710#ifdef CONFIG_PROC_FS
1711 if (!proc_create_net("nfnetlink_queue", 0440, net->nf.proc_netfilter,
1712 &nfqnl_seq_ops, sizeof(struct iter_state)))
1713 return -ENOMEM;
1714#endif
1715 return 0;
1716}
1717
1718static void __net_exit nfnl_queue_net_exit(struct net *net)
1719{
1720 struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1721 unsigned int i;
1722
1723#ifdef CONFIG_PROC_FS
1724 remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter);
1725#endif
1726 for (i = 0; i < INSTANCE_BUCKETS; i++)
1727 WARN_ON_ONCE(!hlist_empty(&q->instance_table[i]));
1728}
1729
1730static struct pernet_operations nfnl_queue_net_ops = {
1731 .init = nfnl_queue_net_init,
1732 .exit = nfnl_queue_net_exit,
1733 .id = &nfnl_queue_net_id,
1734 .size = sizeof(struct nfnl_queue_net),
1735};
1736
1737static int __init nfnetlink_queue_init(void)
1738{
1739 int status;
1740
1741 status = register_pernet_subsys(&nfnl_queue_net_ops);
1742 if (status < 0) {
1743 pr_err("failed to register pernet ops\n");
1744 goto out;
1745 }
1746
1747 netlink_register_notifier(nb: &nfqnl_rtnl_notifier);
1748 status = nfnetlink_subsys_register(n: &nfqnl_subsys);
1749 if (status < 0) {
1750 pr_err("failed to create netlink socket\n");
1751 goto cleanup_netlink_notifier;
1752 }
1753
1754 status = register_netdevice_notifier(nb: &nfqnl_dev_notifier);
1755 if (status < 0) {
1756 pr_err("failed to register netdevice notifier\n");
1757 goto cleanup_netlink_subsys;
1758 }
1759
1760 nf_register_queue_handler(qh: &nfqh);
1761
1762 return status;
1763
1764cleanup_netlink_subsys:
1765 nfnetlink_subsys_unregister(n: &nfqnl_subsys);
1766cleanup_netlink_notifier:
1767 netlink_unregister_notifier(nb: &nfqnl_rtnl_notifier);
1768 unregister_pernet_subsys(&nfnl_queue_net_ops);
1769out:
1770 return status;
1771}
1772
1773static void __exit nfnetlink_queue_fini(void)
1774{
1775 nf_unregister_queue_handler();
1776 unregister_netdevice_notifier(nb: &nfqnl_dev_notifier);
1777 nfnetlink_subsys_unregister(n: &nfqnl_subsys);
1778 netlink_unregister_notifier(nb: &nfqnl_rtnl_notifier);
1779 unregister_pernet_subsys(&nfnl_queue_net_ops);
1780
1781 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1782}
1783
1784MODULE_DESCRIPTION("netfilter packet queue handler");
1785MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1786MODULE_LICENSE("GPL");
1787MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1788
1789module_init(nfnetlink_queue_init);
1790module_exit(nfnetlink_queue_fini);
1791

source code of linux/net/netfilter/nfnetlink_queue.c