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v5.14.15
   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 <net/sock.h>
  33#include <net/tcp_states.h>
  34#include <net/netfilter/nf_queue.h>
  35#include <net/netns/generic.h>
  36
  37#include <linux/atomic.h>
  38
  39#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
  40#include "../bridge/br_private.h"
  41#endif
  42
  43#if IS_ENABLED(CONFIG_NF_CONNTRACK)
  44#include <net/netfilter/nf_conntrack.h>
  45#endif
  46
  47#define NFQNL_QMAX_DEFAULT 1024
  48
  49/* We're using struct nlattr which has 16bit nla_len. Note that nla_len
  50 * includes the header length. Thus, the maximum packet length that we
  51 * support is 65531 bytes. We send truncated packets if the specified length
  52 * is larger than that.  Userspace can check for presence of NFQA_CAP_LEN
  53 * attribute to detect truncation.
  54 */
  55#define NFQNL_MAX_COPY_RANGE (0xffff - NLA_HDRLEN)
  56
  57struct nfqnl_instance {
  58	struct hlist_node hlist;		/* global list of queues */
  59	struct rcu_head rcu;
  60
  61	u32 peer_portid;
  62	unsigned int queue_maxlen;
  63	unsigned int copy_range;
  64	unsigned int queue_dropped;
  65	unsigned int queue_user_dropped;
  66
  67
  68	u_int16_t queue_num;			/* number of this queue */
  69	u_int8_t copy_mode;
  70	u_int32_t flags;			/* Set using NFQA_CFG_FLAGS */
  71/*
  72 * Following fields are dirtied for each queued packet,
  73 * keep them in same cache line if possible.
  74 */
  75	spinlock_t	lock	____cacheline_aligned_in_smp;
  76	unsigned int	queue_total;
  77	unsigned int	id_sequence;		/* 'sequence' of pkt ids */
  78	struct list_head queue_list;		/* packets in queue */
  79};
  80
  81typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
  82
  83static unsigned int nfnl_queue_net_id __read_mostly;
  84
  85#define INSTANCE_BUCKETS	16
  86struct nfnl_queue_net {
  87	spinlock_t instances_lock;
  88	struct hlist_head instance_table[INSTANCE_BUCKETS];
  89};
  90
  91static struct nfnl_queue_net *nfnl_queue_pernet(struct net *net)
  92{
  93	return net_generic(net, nfnl_queue_net_id);
  94}
  95
  96static inline u_int8_t instance_hashfn(u_int16_t queue_num)
  97{
  98	return ((queue_num >> 8) ^ queue_num) % INSTANCE_BUCKETS;
  99}
 100
 101static struct nfqnl_instance *
 102instance_lookup(struct nfnl_queue_net *q, u_int16_t queue_num)
 103{
 104	struct hlist_head *head;
 105	struct nfqnl_instance *inst;
 106
 107	head = &q->instance_table[instance_hashfn(queue_num)];
 108	hlist_for_each_entry_rcu(inst, head, hlist) {
 109		if (inst->queue_num == queue_num)
 110			return inst;
 111	}
 112	return NULL;
 113}
 114
 115static struct nfqnl_instance *
 116instance_create(struct nfnl_queue_net *q, u_int16_t queue_num, u32 portid)
 117{
 118	struct nfqnl_instance *inst;
 119	unsigned int h;
 120	int err;
 121
 122	spin_lock(&q->instances_lock);
 123	if (instance_lookup(q, queue_num)) {
 124		err = -EEXIST;
 125		goto out_unlock;
 126	}
 127
 128	inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
 129	if (!inst) {
 130		err = -ENOMEM;
 131		goto out_unlock;
 132	}
 133
 134	inst->queue_num = queue_num;
 135	inst->peer_portid = portid;
 136	inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
 137	inst->copy_range = NFQNL_MAX_COPY_RANGE;
 138	inst->copy_mode = NFQNL_COPY_NONE;
 139	spin_lock_init(&inst->lock);
 140	INIT_LIST_HEAD(&inst->queue_list);
 141
 142	if (!try_module_get(THIS_MODULE)) {
 143		err = -EAGAIN;
 144		goto out_free;
 145	}
 146
 147	h = instance_hashfn(queue_num);
 148	hlist_add_head_rcu(&inst->hlist, &q->instance_table[h]);
 149
 150	spin_unlock(&q->instances_lock);
 151
 152	return inst;
 153
 154out_free:
 155	kfree(inst);
 156out_unlock:
 157	spin_unlock(&q->instances_lock);
 158	return ERR_PTR(err);
 159}
 160
 161static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
 162			unsigned long data);
 163
 164static void
 165instance_destroy_rcu(struct rcu_head *head)
 166{
 167	struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
 168						   rcu);
 169
 170	nfqnl_flush(inst, NULL, 0);
 171	kfree(inst);
 172	module_put(THIS_MODULE);
 173}
 174
 175static void
 176__instance_destroy(struct nfqnl_instance *inst)
 177{
 178	hlist_del_rcu(&inst->hlist);
 179	call_rcu(&inst->rcu, instance_destroy_rcu);
 180}
 181
 182static void
 183instance_destroy(struct nfnl_queue_net *q, struct nfqnl_instance *inst)
 184{
 185	spin_lock(&q->instances_lock);
 186	__instance_destroy(inst);
 187	spin_unlock(&q->instances_lock);
 188}
 189
 190static inline void
 191__enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 192{
 193       list_add_tail(&entry->list, &queue->queue_list);
 194       queue->queue_total++;
 195}
 196
 197static void
 198__dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 199{
 200	list_del(&entry->list);
 201	queue->queue_total--;
 202}
 203
 204static struct nf_queue_entry *
 205find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
 206{
 207	struct nf_queue_entry *entry = NULL, *i;
 208
 209	spin_lock_bh(&queue->lock);
 210
 211	list_for_each_entry(i, &queue->queue_list, list) {
 212		if (i->id == id) {
 213			entry = i;
 214			break;
 215		}
 216	}
 217
 218	if (entry)
 219		__dequeue_entry(queue, entry);
 220
 221	spin_unlock_bh(&queue->lock);
 222
 223	return entry;
 224}
 225
 226static void nfqnl_reinject(struct nf_queue_entry *entry, unsigned int verdict)
 227{
 228	struct nf_ct_hook *ct_hook;
 229	int err;
 230
 231	if (verdict == NF_ACCEPT ||
 232	    verdict == NF_REPEAT ||
 233	    verdict == NF_STOP) {
 234		rcu_read_lock();
 235		ct_hook = rcu_dereference(nf_ct_hook);
 236		if (ct_hook) {
 237			err = ct_hook->update(entry->state.net, entry->skb);
 238			if (err < 0)
 239				verdict = NF_DROP;
 240		}
 241		rcu_read_unlock();
 242	}
 243	nf_reinject(entry, verdict);
 244}
 245
 246static void
 247nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
 248{
 249	struct nf_queue_entry *entry, *next;
 250
 251	spin_lock_bh(&queue->lock);
 252	list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
 253		if (!cmpfn || cmpfn(entry, data)) {
 254			list_del(&entry->list);
 255			queue->queue_total--;
 256			nfqnl_reinject(entry, NF_DROP);
 257		}
 258	}
 259	spin_unlock_bh(&queue->lock);
 260}
 261
 262static int
 263nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
 264		      bool csum_verify)
 265{
 266	__u32 flags = 0;
 267
 268	if (packet->ip_summed == CHECKSUM_PARTIAL)
 269		flags = NFQA_SKB_CSUMNOTREADY;
 270	else if (csum_verify)
 271		flags = NFQA_SKB_CSUM_NOTVERIFIED;
 272
 273	if (skb_is_gso(packet))
 274		flags |= NFQA_SKB_GSO;
 275
 276	return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
 277}
 278
 279static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
 280{
 281	const struct cred *cred;
 282
 283	if (!sk_fullsock(sk))
 284		return 0;
 285
 286	read_lock_bh(&sk->sk_callback_lock);
 287	if (sk->sk_socket && sk->sk_socket->file) {
 288		cred = sk->sk_socket->file->f_cred;
 289		if (nla_put_be32(skb, NFQA_UID,
 290		    htonl(from_kuid_munged(&init_user_ns, cred->fsuid))))
 291			goto nla_put_failure;
 292		if (nla_put_be32(skb, NFQA_GID,
 293		    htonl(from_kgid_munged(&init_user_ns, cred->fsgid))))
 294			goto nla_put_failure;
 295	}
 296	read_unlock_bh(&sk->sk_callback_lock);
 297	return 0;
 298
 299nla_put_failure:
 300	read_unlock_bh(&sk->sk_callback_lock);
 301	return -1;
 302}
 303
 304static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
 305{
 306	u32 seclen = 0;
 307#if IS_ENABLED(CONFIG_NETWORK_SECMARK)
 308	if (!skb || !sk_fullsock(skb->sk))
 309		return 0;
 310
 311	read_lock_bh(&skb->sk->sk_callback_lock);
 312
 313	if (skb->secmark)
 314		security_secid_to_secctx(skb->secmark, secdata, &seclen);
 315
 316	read_unlock_bh(&skb->sk->sk_callback_lock);
 317#endif
 318	return seclen;
 319}
 320
 321static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
 322{
 323	struct sk_buff *entskb = entry->skb;
 324	u32 nlalen = 0;
 325
 326	if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
 327		return 0;
 328
 329	if (skb_vlan_tag_present(entskb))
 330		nlalen += nla_total_size(nla_total_size(sizeof(__be16)) +
 331					 nla_total_size(sizeof(__be16)));
 332
 333	if (entskb->network_header > entskb->mac_header)
 334		nlalen += nla_total_size((entskb->network_header -
 335					  entskb->mac_header));
 336
 337	return nlalen;
 338}
 339
 340static int nfqnl_put_bridge(struct nf_queue_entry *entry, struct sk_buff *skb)
 341{
 342	struct sk_buff *entskb = entry->skb;
 343
 344	if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
 345		return 0;
 346
 347	if (skb_vlan_tag_present(entskb)) {
 348		struct nlattr *nest;
 349
 350		nest = nla_nest_start(skb, NFQA_VLAN);
 351		if (!nest)
 352			goto nla_put_failure;
 353
 354		if (nla_put_be16(skb, NFQA_VLAN_TCI, htons(entskb->vlan_tci)) ||
 355		    nla_put_be16(skb, NFQA_VLAN_PROTO, entskb->vlan_proto))
 356			goto nla_put_failure;
 357
 358		nla_nest_end(skb, nest);
 359	}
 360
 361	if (entskb->mac_header < entskb->network_header) {
 362		int len = (int)(entskb->network_header - entskb->mac_header);
 363
 364		if (nla_put(skb, NFQA_L2HDR, len, skb_mac_header(entskb)))
 365			goto nla_put_failure;
 366	}
 367
 368	return 0;
 369
 370nla_put_failure:
 371	return -1;
 372}
 373
 374static struct sk_buff *
 375nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 376			   struct nf_queue_entry *entry,
 377			   __be32 **packet_id_ptr)
 378{
 379	size_t size;
 380	size_t data_len = 0, cap_len = 0;
 381	unsigned int hlen = 0;
 382	struct sk_buff *skb;
 383	struct nlattr *nla;
 384	struct nfqnl_msg_packet_hdr *pmsg;
 385	struct nlmsghdr *nlh;
 
 386	struct sk_buff *entskb = entry->skb;
 387	struct net_device *indev;
 388	struct net_device *outdev;
 389	struct nf_conn *ct = NULL;
 390	enum ip_conntrack_info ctinfo;
 391	struct nfnl_ct_hook *nfnl_ct;
 392	bool csum_verify;
 393	char *secdata = NULL;
 394	u32 seclen = 0;
 395
 396	size = nlmsg_total_size(sizeof(struct nfgenmsg))
 397		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
 398		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 399		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 400#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 401		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 402		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 403#endif
 404		+ nla_total_size(sizeof(u_int32_t))	/* mark */
 405		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
 406		+ nla_total_size(sizeof(u_int32_t))	/* skbinfo */
 407		+ nla_total_size(sizeof(u_int32_t));	/* cap_len */
 408
 409	if (entskb->tstamp)
 410		size += nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
 411
 412	size += nfqnl_get_bridge_size(entry);
 413
 414	if (entry->state.hook <= NF_INET_FORWARD ||
 415	   (entry->state.hook == NF_INET_POST_ROUTING && entskb->sk == NULL))
 416		csum_verify = !skb_csum_unnecessary(entskb);
 417	else
 418		csum_verify = false;
 419
 420	outdev = entry->state.out;
 421
 422	switch ((enum nfqnl_config_mode)READ_ONCE(queue->copy_mode)) {
 423	case NFQNL_COPY_META:
 424	case NFQNL_COPY_NONE:
 425		break;
 426
 427	case NFQNL_COPY_PACKET:
 428		if (!(queue->flags & NFQA_CFG_F_GSO) &&
 429		    entskb->ip_summed == CHECKSUM_PARTIAL &&
 430		    skb_checksum_help(entskb))
 431			return NULL;
 432
 433		data_len = READ_ONCE(queue->copy_range);
 434		if (data_len > entskb->len)
 435			data_len = entskb->len;
 436
 437		hlen = skb_zerocopy_headlen(entskb);
 438		hlen = min_t(unsigned int, hlen, data_len);
 439		size += sizeof(struct nlattr) + hlen;
 440		cap_len = entskb->len;
 441		break;
 442	}
 443
 444	nfnl_ct = rcu_dereference(nfnl_ct_hook);
 445
 446#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 447	if (queue->flags & NFQA_CFG_F_CONNTRACK) {
 448		if (nfnl_ct != NULL) {
 449			ct = nf_ct_get(entskb, &ctinfo);
 450			if (ct != NULL)
 451				size += nfnl_ct->build_size(ct);
 452		}
 453	}
 454#endif
 455
 456	if (queue->flags & NFQA_CFG_F_UID_GID) {
 457		size += (nla_total_size(sizeof(u_int32_t))	/* uid */
 458			+ nla_total_size(sizeof(u_int32_t)));	/* gid */
 459	}
 460
 461	if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
 462		seclen = nfqnl_get_sk_secctx(entskb, &secdata);
 463		if (seclen)
 464			size += nla_total_size(seclen);
 465	}
 466
 467	skb = alloc_skb(size, GFP_ATOMIC);
 468	if (!skb) {
 469		skb_tx_error(entskb);
 470		goto nlmsg_failure;
 471	}
 472
 473	nlh = nfnl_msg_put(skb, 0, 0,
 474			   nfnl_msg_type(NFNL_SUBSYS_QUEUE, NFQNL_MSG_PACKET),
 475			   0, entry->state.pf, NFNETLINK_V0,
 476			   htons(queue->queue_num));
 477	if (!nlh) {
 478		skb_tx_error(entskb);
 479		kfree_skb(skb);
 480		goto nlmsg_failure;
 481	}
 
 
 
 
 482
 483	nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
 484	pmsg = nla_data(nla);
 485	pmsg->hw_protocol	= entskb->protocol;
 486	pmsg->hook		= entry->state.hook;
 487	*packet_id_ptr		= &pmsg->packet_id;
 488
 489	indev = entry->state.in;
 490	if (indev) {
 491#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 492		if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
 493			goto nla_put_failure;
 494#else
 495		if (entry->state.pf == PF_BRIDGE) {
 496			/* Case 1: indev is physical input device, we need to
 497			 * look for bridge group (when called from
 498			 * netfilter_bridge) */
 499			if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 500					 htonl(indev->ifindex)) ||
 501			/* this is the bridge group "brX" */
 502			/* rcu_read_lock()ed by __nf_queue */
 503			    nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 504					 htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
 505				goto nla_put_failure;
 506		} else {
 507			int physinif;
 508
 509			/* Case 2: indev is bridge group, we need to look for
 510			 * physical device (when called from ipv4) */
 511			if (nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 512					 htonl(indev->ifindex)))
 513				goto nla_put_failure;
 514
 515			physinif = nf_bridge_get_physinif(entskb);
 516			if (physinif &&
 517			    nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 518					 htonl(physinif)))
 519				goto nla_put_failure;
 520		}
 521#endif
 522	}
 523
 524	if (outdev) {
 525#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 526		if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
 527			goto nla_put_failure;
 528#else
 529		if (entry->state.pf == PF_BRIDGE) {
 530			/* Case 1: outdev is physical output device, we need to
 531			 * look for bridge group (when called from
 532			 * netfilter_bridge) */
 533			if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 534					 htonl(outdev->ifindex)) ||
 535			/* this is the bridge group "brX" */
 536			/* rcu_read_lock()ed by __nf_queue */
 537			    nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 538					 htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
 539				goto nla_put_failure;
 540		} else {
 541			int physoutif;
 542
 543			/* Case 2: outdev is bridge group, we need to look for
 544			 * physical output device (when called from ipv4) */
 545			if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 546					 htonl(outdev->ifindex)))
 547				goto nla_put_failure;
 548
 549			physoutif = nf_bridge_get_physoutif(entskb);
 550			if (physoutif &&
 551			    nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 552					 htonl(physoutif)))
 553				goto nla_put_failure;
 554		}
 555#endif
 556	}
 557
 558	if (entskb->mark &&
 559	    nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark)))
 560		goto nla_put_failure;
 561
 562	if (indev && entskb->dev &&
 563	    entskb->mac_header != entskb->network_header) {
 564		struct nfqnl_msg_packet_hw phw;
 565		int len;
 566
 567		memset(&phw, 0, sizeof(phw));
 568		len = dev_parse_header(entskb, phw.hw_addr);
 569		if (len) {
 570			phw.hw_addrlen = htons(len);
 571			if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw))
 572				goto nla_put_failure;
 573		}
 574	}
 575
 576	if (nfqnl_put_bridge(entry, skb) < 0)
 577		goto nla_put_failure;
 578
 579	if (entry->state.hook <= NF_INET_FORWARD && entskb->tstamp) {
 580		struct nfqnl_msg_packet_timestamp ts;
 581		struct timespec64 kts = ktime_to_timespec64(entskb->tstamp);
 582
 583		ts.sec = cpu_to_be64(kts.tv_sec);
 584		ts.usec = cpu_to_be64(kts.tv_nsec / NSEC_PER_USEC);
 585
 586		if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
 587			goto nla_put_failure;
 588	}
 589
 590	if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk &&
 591	    nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)
 592		goto nla_put_failure;
 593
 594	if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
 595		goto nla_put_failure;
 596
 597	if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
 598		goto nla_put_failure;
 599
 600	if (cap_len > data_len &&
 601	    nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len)))
 602		goto nla_put_failure;
 603
 604	if (nfqnl_put_packet_info(skb, entskb, csum_verify))
 605		goto nla_put_failure;
 606
 607	if (data_len) {
 608		struct nlattr *nla;
 609
 610		if (skb_tailroom(skb) < sizeof(*nla) + hlen)
 611			goto nla_put_failure;
 612
 613		nla = skb_put(skb, sizeof(*nla));
 614		nla->nla_type = NFQA_PAYLOAD;
 615		nla->nla_len = nla_attr_size(data_len);
 616
 617		if (skb_zerocopy(skb, entskb, data_len, hlen))
 618			goto nla_put_failure;
 619	}
 620
 621	nlh->nlmsg_len = skb->len;
 622	if (seclen)
 623		security_release_secctx(secdata, seclen);
 624	return skb;
 625
 626nla_put_failure:
 627	skb_tx_error(entskb);
 628	kfree_skb(skb);
 629	net_err_ratelimited("nf_queue: error creating packet message\n");
 630nlmsg_failure:
 631	if (seclen)
 632		security_release_secctx(secdata, seclen);
 633	return NULL;
 634}
 635
 636static bool nf_ct_drop_unconfirmed(const struct nf_queue_entry *entry)
 637{
 638#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 639	static const unsigned long flags = IPS_CONFIRMED | IPS_DYING;
 640	const struct nf_conn *ct = (void *)skb_nfct(entry->skb);
 641
 642	if (ct && ((ct->status & flags) == IPS_DYING))
 643		return true;
 644#endif
 645	return false;
 646}
 647
 648static int
 649__nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue,
 650			struct nf_queue_entry *entry)
 651{
 652	struct sk_buff *nskb;
 653	int err = -ENOBUFS;
 654	__be32 *packet_id_ptr;
 655	int failopen = 0;
 656
 657	nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr);
 658	if (nskb == NULL) {
 659		err = -ENOMEM;
 660		goto err_out;
 661	}
 662	spin_lock_bh(&queue->lock);
 663
 664	if (nf_ct_drop_unconfirmed(entry))
 665		goto err_out_free_nskb;
 666
 667	if (queue->queue_total >= queue->queue_maxlen) {
 668		if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 669			failopen = 1;
 670			err = 0;
 671		} else {
 672			queue->queue_dropped++;
 673			net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
 674					     queue->queue_total);
 675		}
 676		goto err_out_free_nskb;
 677	}
 678	entry->id = ++queue->id_sequence;
 679	*packet_id_ptr = htonl(entry->id);
 680
 681	/* nfnetlink_unicast will either free the nskb or add it to a socket */
 682	err = nfnetlink_unicast(nskb, net, queue->peer_portid);
 683	if (err < 0) {
 684		if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 685			failopen = 1;
 686			err = 0;
 687		} else {
 688			queue->queue_user_dropped++;
 689		}
 690		goto err_out_unlock;
 691	}
 692
 693	__enqueue_entry(queue, entry);
 694
 695	spin_unlock_bh(&queue->lock);
 696	return 0;
 697
 698err_out_free_nskb:
 699	kfree_skb(nskb);
 700err_out_unlock:
 701	spin_unlock_bh(&queue->lock);
 702	if (failopen)
 703		nfqnl_reinject(entry, NF_ACCEPT);
 704err_out:
 705	return err;
 706}
 707
 708static struct nf_queue_entry *
 709nf_queue_entry_dup(struct nf_queue_entry *e)
 710{
 711	struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC);
 712	if (entry)
 713		nf_queue_entry_get_refs(entry);
 714	return entry;
 715}
 716
 717#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 718/* When called from bridge netfilter, skb->data must point to MAC header
 719 * before calling skb_gso_segment(). Else, original MAC header is lost
 720 * and segmented skbs will be sent to wrong destination.
 721 */
 722static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
 723{
 724	if (nf_bridge_info_get(skb))
 725		__skb_push(skb, skb->network_header - skb->mac_header);
 726}
 727
 728static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
 729{
 730	if (nf_bridge_info_get(skb))
 731		__skb_pull(skb, skb->network_header - skb->mac_header);
 732}
 733#else
 734#define nf_bridge_adjust_skb_data(s) do {} while (0)
 735#define nf_bridge_adjust_segmented_data(s) do {} while (0)
 736#endif
 737
 738static int
 739__nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue,
 740			   struct sk_buff *skb, struct nf_queue_entry *entry)
 741{
 742	int ret = -ENOMEM;
 743	struct nf_queue_entry *entry_seg;
 744
 745	nf_bridge_adjust_segmented_data(skb);
 746
 747	if (skb->next == NULL) { /* last packet, no need to copy entry */
 748		struct sk_buff *gso_skb = entry->skb;
 749		entry->skb = skb;
 750		ret = __nfqnl_enqueue_packet(net, queue, entry);
 751		if (ret)
 752			entry->skb = gso_skb;
 753		return ret;
 754	}
 755
 756	skb_mark_not_on_list(skb);
 757
 758	entry_seg = nf_queue_entry_dup(entry);
 759	if (entry_seg) {
 760		entry_seg->skb = skb;
 761		ret = __nfqnl_enqueue_packet(net, queue, entry_seg);
 762		if (ret)
 763			nf_queue_entry_free(entry_seg);
 764	}
 765	return ret;
 766}
 767
 768static int
 769nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 770{
 771	unsigned int queued;
 772	struct nfqnl_instance *queue;
 773	struct sk_buff *skb, *segs, *nskb;
 774	int err = -ENOBUFS;
 775	struct net *net = entry->state.net;
 776	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 777
 778	/* rcu_read_lock()ed by nf_hook_thresh */
 779	queue = instance_lookup(q, queuenum);
 780	if (!queue)
 781		return -ESRCH;
 782
 783	if (queue->copy_mode == NFQNL_COPY_NONE)
 784		return -EINVAL;
 785
 786	skb = entry->skb;
 787
 788	switch (entry->state.pf) {
 789	case NFPROTO_IPV4:
 790		skb->protocol = htons(ETH_P_IP);
 791		break;
 792	case NFPROTO_IPV6:
 793		skb->protocol = htons(ETH_P_IPV6);
 794		break;
 795	}
 796
 797	if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb))
 798		return __nfqnl_enqueue_packet(net, queue, entry);
 799
 800	nf_bridge_adjust_skb_data(skb);
 801	segs = skb_gso_segment(skb, 0);
 802	/* Does not use PTR_ERR to limit the number of error codes that can be
 803	 * returned by nf_queue.  For instance, callers rely on -ESRCH to
 804	 * mean 'ignore this hook'.
 805	 */
 806	if (IS_ERR_OR_NULL(segs))
 807		goto out_err;
 808	queued = 0;
 809	err = 0;
 810	skb_list_walk_safe(segs, segs, nskb) {
 811		if (err == 0)
 812			err = __nfqnl_enqueue_packet_gso(net, queue,
 813							segs, entry);
 814		if (err == 0)
 815			queued++;
 816		else
 817			kfree_skb(segs);
 818	}
 819
 820	if (queued) {
 821		if (err) /* some segments are already queued */
 822			nf_queue_entry_free(entry);
 823		kfree_skb(skb);
 824		return 0;
 825	}
 826 out_err:
 827	nf_bridge_adjust_segmented_data(skb);
 828	return err;
 829}
 830
 831static int
 832nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff)
 833{
 834	struct sk_buff *nskb;
 835
 836	if (diff < 0) {
 837		if (pskb_trim(e->skb, data_len))
 838			return -ENOMEM;
 839	} else if (diff > 0) {
 840		if (data_len > 0xFFFF)
 841			return -EINVAL;
 842		if (diff > skb_tailroom(e->skb)) {
 843			nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
 844					       diff, GFP_ATOMIC);
 845			if (!nskb)
 846				return -ENOMEM;
 847			kfree_skb(e->skb);
 848			e->skb = nskb;
 849		}
 850		skb_put(e->skb, diff);
 851	}
 852	if (skb_ensure_writable(e->skb, data_len))
 853		return -ENOMEM;
 854	skb_copy_to_linear_data(e->skb, data, data_len);
 855	e->skb->ip_summed = CHECKSUM_NONE;
 856	return 0;
 857}
 858
 859static int
 860nfqnl_set_mode(struct nfqnl_instance *queue,
 861	       unsigned char mode, unsigned int range)
 862{
 863	int status = 0;
 864
 865	spin_lock_bh(&queue->lock);
 866	switch (mode) {
 867	case NFQNL_COPY_NONE:
 868	case NFQNL_COPY_META:
 869		queue->copy_mode = mode;
 870		queue->copy_range = 0;
 871		break;
 872
 873	case NFQNL_COPY_PACKET:
 874		queue->copy_mode = mode;
 875		if (range == 0 || range > NFQNL_MAX_COPY_RANGE)
 876			queue->copy_range = NFQNL_MAX_COPY_RANGE;
 877		else
 878			queue->copy_range = range;
 879		break;
 880
 881	default:
 882		status = -EINVAL;
 883
 884	}
 885	spin_unlock_bh(&queue->lock);
 886
 887	return status;
 888}
 889
 890static int
 891dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
 892{
 893#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 894	int physinif, physoutif;
 895
 896	physinif = nf_bridge_get_physinif(entry->skb);
 897	physoutif = nf_bridge_get_physoutif(entry->skb);
 898
 899	if (physinif == ifindex || physoutif == ifindex)
 900		return 1;
 901#endif
 902	if (entry->state.in)
 903		if (entry->state.in->ifindex == ifindex)
 904			return 1;
 905	if (entry->state.out)
 906		if (entry->state.out->ifindex == ifindex)
 907			return 1;
 908
 909	return 0;
 910}
 911
 912/* drop all packets with either indev or outdev == ifindex from all queue
 913 * instances */
 914static void
 915nfqnl_dev_drop(struct net *net, int ifindex)
 916{
 917	int i;
 918	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 919
 920	rcu_read_lock();
 921
 922	for (i = 0; i < INSTANCE_BUCKETS; i++) {
 923		struct nfqnl_instance *inst;
 924		struct hlist_head *head = &q->instance_table[i];
 925
 926		hlist_for_each_entry_rcu(inst, head, hlist)
 927			nfqnl_flush(inst, dev_cmp, ifindex);
 928	}
 929
 930	rcu_read_unlock();
 931}
 932
 933static int
 934nfqnl_rcv_dev_event(struct notifier_block *this,
 935		    unsigned long event, void *ptr)
 936{
 937	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 938
 939	/* Drop any packets associated with the downed device */
 940	if (event == NETDEV_DOWN)
 941		nfqnl_dev_drop(dev_net(dev), dev->ifindex);
 942	return NOTIFY_DONE;
 943}
 944
 945static struct notifier_block nfqnl_dev_notifier = {
 946	.notifier_call	= nfqnl_rcv_dev_event,
 947};
 948
 949static void nfqnl_nf_hook_drop(struct net *net)
 950{
 951	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 952	int i;
 953
 954	for (i = 0; i < INSTANCE_BUCKETS; i++) {
 955		struct nfqnl_instance *inst;
 956		struct hlist_head *head = &q->instance_table[i];
 957
 958		hlist_for_each_entry_rcu(inst, head, hlist)
 959			nfqnl_flush(inst, NULL, 0);
 960	}
 961}
 962
 963static int
 964nfqnl_rcv_nl_event(struct notifier_block *this,
 965		   unsigned long event, void *ptr)
 966{
 967	struct netlink_notify *n = ptr;
 968	struct nfnl_queue_net *q = nfnl_queue_pernet(n->net);
 969
 970	if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
 971		int i;
 972
 973		/* destroy all instances for this portid */
 974		spin_lock(&q->instances_lock);
 975		for (i = 0; i < INSTANCE_BUCKETS; i++) {
 976			struct hlist_node *t2;
 977			struct nfqnl_instance *inst;
 978			struct hlist_head *head = &q->instance_table[i];
 979
 980			hlist_for_each_entry_safe(inst, t2, head, hlist) {
 981				if (n->portid == inst->peer_portid)
 982					__instance_destroy(inst);
 983			}
 984		}
 985		spin_unlock(&q->instances_lock);
 986	}
 987	return NOTIFY_DONE;
 988}
 989
 990static struct notifier_block nfqnl_rtnl_notifier = {
 991	.notifier_call	= nfqnl_rcv_nl_event,
 992};
 993
 994static const struct nla_policy nfqa_vlan_policy[NFQA_VLAN_MAX + 1] = {
 995	[NFQA_VLAN_TCI]		= { .type = NLA_U16},
 996	[NFQA_VLAN_PROTO]	= { .type = NLA_U16},
 997};
 998
 999static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
1000	[NFQA_VERDICT_HDR]	= { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
1001	[NFQA_MARK]		= { .type = NLA_U32 },
1002	[NFQA_PAYLOAD]		= { .type = NLA_UNSPEC },
1003	[NFQA_CT]		= { .type = NLA_UNSPEC },
1004	[NFQA_EXP]		= { .type = NLA_UNSPEC },
1005	[NFQA_VLAN]		= { .type = NLA_NESTED },
1006};
1007
1008static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
1009	[NFQA_VERDICT_HDR]	= { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
1010	[NFQA_MARK]		= { .type = NLA_U32 },
1011};
1012
1013static struct nfqnl_instance *
1014verdict_instance_lookup(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid)
1015{
1016	struct nfqnl_instance *queue;
1017
1018	queue = instance_lookup(q, queue_num);
1019	if (!queue)
1020		return ERR_PTR(-ENODEV);
1021
1022	if (queue->peer_portid != nlportid)
1023		return ERR_PTR(-EPERM);
1024
1025	return queue;
1026}
1027
1028static struct nfqnl_msg_verdict_hdr*
1029verdicthdr_get(const struct nlattr * const nfqa[])
1030{
1031	struct nfqnl_msg_verdict_hdr *vhdr;
1032	unsigned int verdict;
1033
1034	if (!nfqa[NFQA_VERDICT_HDR])
1035		return NULL;
1036
1037	vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
1038	verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
1039	if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
1040		return NULL;
1041	return vhdr;
1042}
1043
1044static int nfq_id_after(unsigned int id, unsigned int max)
1045{
1046	return (int)(id - max) > 0;
1047}
1048
1049static int nfqnl_recv_verdict_batch(struct sk_buff *skb,
1050				    const struct nfnl_info *info,
1051				    const struct nlattr * const nfqa[])
 
 
1052{
1053	struct nfnl_queue_net *q = nfnl_queue_pernet(info->net);
1054	u16 queue_num = ntohs(info->nfmsg->res_id);
1055	struct nf_queue_entry *entry, *tmp;
 
1056	struct nfqnl_msg_verdict_hdr *vhdr;
1057	struct nfqnl_instance *queue;
1058	unsigned int verdict, maxid;
1059	LIST_HEAD(batch_list);
 
 
1060
1061	queue = verdict_instance_lookup(q, queue_num,
1062					NETLINK_CB(skb).portid);
1063	if (IS_ERR(queue))
1064		return PTR_ERR(queue);
1065
1066	vhdr = verdicthdr_get(nfqa);
1067	if (!vhdr)
1068		return -EINVAL;
1069
1070	verdict = ntohl(vhdr->verdict);
1071	maxid = ntohl(vhdr->id);
1072
1073	spin_lock_bh(&queue->lock);
1074
1075	list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
1076		if (nfq_id_after(entry->id, maxid))
1077			break;
1078		__dequeue_entry(queue, entry);
1079		list_add_tail(&entry->list, &batch_list);
1080	}
1081
1082	spin_unlock_bh(&queue->lock);
1083
1084	if (list_empty(&batch_list))
1085		return -ENOENT;
1086
1087	list_for_each_entry_safe(entry, tmp, &batch_list, list) {
1088		if (nfqa[NFQA_MARK])
1089			entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1090
1091		nfqnl_reinject(entry, verdict);
1092	}
1093	return 0;
1094}
1095
1096static struct nf_conn *nfqnl_ct_parse(struct nfnl_ct_hook *nfnl_ct,
1097				      const struct nlmsghdr *nlh,
1098				      const struct nlattr * const nfqa[],
1099				      struct nf_queue_entry *entry,
1100				      enum ip_conntrack_info *ctinfo)
1101{
1102#if IS_ENABLED(CONFIG_NF_CONNTRACK)
1103	struct nf_conn *ct;
1104
1105	ct = nf_ct_get(entry->skb, ctinfo);
1106	if (ct == NULL)
1107		return NULL;
1108
1109	if (nfnl_ct->parse(nfqa[NFQA_CT], ct) < 0)
1110		return NULL;
1111
1112	if (nfqa[NFQA_EXP])
1113		nfnl_ct->attach_expect(nfqa[NFQA_EXP], ct,
1114				      NETLINK_CB(entry->skb).portid,
1115				      nlmsg_report(nlh));
1116	return ct;
1117#else
1118	return NULL;
1119#endif
1120}
1121
1122static int nfqa_parse_bridge(struct nf_queue_entry *entry,
1123			     const struct nlattr * const nfqa[])
1124{
1125	if (nfqa[NFQA_VLAN]) {
1126		struct nlattr *tb[NFQA_VLAN_MAX + 1];
1127		int err;
1128
1129		err = nla_parse_nested_deprecated(tb, NFQA_VLAN_MAX,
1130						  nfqa[NFQA_VLAN],
1131						  nfqa_vlan_policy, NULL);
1132		if (err < 0)
1133			return err;
1134
1135		if (!tb[NFQA_VLAN_TCI] || !tb[NFQA_VLAN_PROTO])
1136			return -EINVAL;
1137
1138		__vlan_hwaccel_put_tag(entry->skb,
1139			nla_get_be16(tb[NFQA_VLAN_PROTO]),
1140			ntohs(nla_get_be16(tb[NFQA_VLAN_TCI])));
1141	}
1142
1143	if (nfqa[NFQA_L2HDR]) {
1144		int mac_header_len = entry->skb->network_header -
1145			entry->skb->mac_header;
1146
1147		if (mac_header_len != nla_len(nfqa[NFQA_L2HDR]))
1148			return -EINVAL;
1149		else if (mac_header_len > 0)
1150			memcpy(skb_mac_header(entry->skb),
1151			       nla_data(nfqa[NFQA_L2HDR]),
1152			       mac_header_len);
1153	}
1154
1155	return 0;
1156}
1157
1158static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info,
1159			      const struct nlattr * const nfqa[])
 
 
 
1160{
1161	struct nfnl_queue_net *q = nfnl_queue_pernet(info->net);
1162	u_int16_t queue_num = ntohs(info->nfmsg->res_id);
1163	struct nfqnl_msg_verdict_hdr *vhdr;
1164	enum ip_conntrack_info ctinfo;
1165	struct nfqnl_instance *queue;
 
1166	struct nf_queue_entry *entry;
 
1167	struct nfnl_ct_hook *nfnl_ct;
1168	struct nf_conn *ct = NULL;
1169	unsigned int verdict;
1170	int err;
1171
1172	queue = verdict_instance_lookup(q, queue_num,
1173					NETLINK_CB(skb).portid);
1174	if (IS_ERR(queue))
1175		return PTR_ERR(queue);
1176
1177	vhdr = verdicthdr_get(nfqa);
1178	if (!vhdr)
1179		return -EINVAL;
1180
1181	verdict = ntohl(vhdr->verdict);
1182
1183	entry = find_dequeue_entry(queue, ntohl(vhdr->id));
1184	if (entry == NULL)
1185		return -ENOENT;
1186
1187	/* rcu lock already held from nfnl->call_rcu. */
1188	nfnl_ct = rcu_dereference(nfnl_ct_hook);
1189
1190	if (nfqa[NFQA_CT]) {
1191		if (nfnl_ct != NULL)
1192			ct = nfqnl_ct_parse(nfnl_ct, info->nlh, nfqa, entry,
1193					    &ctinfo);
1194	}
1195
1196	if (entry->state.pf == PF_BRIDGE) {
1197		err = nfqa_parse_bridge(entry, nfqa);
1198		if (err < 0)
1199			return err;
1200	}
1201
1202	if (nfqa[NFQA_PAYLOAD]) {
1203		u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]);
1204		int diff = payload_len - entry->skb->len;
1205
1206		if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
1207				 payload_len, entry, diff) < 0)
1208			verdict = NF_DROP;
1209
1210		if (ct && diff)
1211			nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff);
1212	}
1213
1214	if (nfqa[NFQA_MARK])
1215		entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1216
1217	nfqnl_reinject(entry, verdict);
1218	return 0;
1219}
1220
1221static int nfqnl_recv_unsupp(struct sk_buff *skb, const struct nfnl_info *info,
1222			     const struct nlattr * const cda[])
 
 
1223{
1224	return -ENOTSUPP;
1225}
1226
1227static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
1228	[NFQA_CFG_CMD]		= { .len = sizeof(struct nfqnl_msg_config_cmd) },
1229	[NFQA_CFG_PARAMS]	= { .len = sizeof(struct nfqnl_msg_config_params) },
1230	[NFQA_CFG_QUEUE_MAXLEN]	= { .type = NLA_U32 },
1231	[NFQA_CFG_MASK]		= { .type = NLA_U32 },
1232	[NFQA_CFG_FLAGS]	= { .type = NLA_U32 },
1233};
1234
1235static const struct nf_queue_handler nfqh = {
1236	.outfn		= nfqnl_enqueue_packet,
1237	.nf_hook_drop	= nfqnl_nf_hook_drop,
1238};
1239
1240static int nfqnl_recv_config(struct sk_buff *skb, const struct nfnl_info *info,
1241			     const struct nlattr * const nfqa[])
 
 
1242{
1243	struct nfnl_queue_net *q = nfnl_queue_pernet(info->net);
1244	u_int16_t queue_num = ntohs(info->nfmsg->res_id);
1245	struct nfqnl_msg_config_cmd *cmd = NULL;
1246	struct nfqnl_instance *queue;
 
 
1247	__u32 flags = 0, mask = 0;
1248	int ret = 0;
1249
1250	if (nfqa[NFQA_CFG_CMD]) {
1251		cmd = nla_data(nfqa[NFQA_CFG_CMD]);
1252
1253		/* Obsolete commands without queue context */
1254		switch (cmd->command) {
1255		case NFQNL_CFG_CMD_PF_BIND: return 0;
1256		case NFQNL_CFG_CMD_PF_UNBIND: return 0;
1257		}
1258	}
1259
1260	/* Check if we support these flags in first place, dependencies should
1261	 * be there too not to break atomicity.
1262	 */
1263	if (nfqa[NFQA_CFG_FLAGS]) {
1264		if (!nfqa[NFQA_CFG_MASK]) {
1265			/* A mask is needed to specify which flags are being
1266			 * changed.
1267			 */
1268			return -EINVAL;
1269		}
1270
1271		flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
1272		mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
1273
1274		if (flags >= NFQA_CFG_F_MAX)
1275			return -EOPNOTSUPP;
1276
1277#if !IS_ENABLED(CONFIG_NETWORK_SECMARK)
1278		if (flags & mask & NFQA_CFG_F_SECCTX)
1279			return -EOPNOTSUPP;
1280#endif
1281		if ((flags & mask & NFQA_CFG_F_CONNTRACK) &&
1282		    !rcu_access_pointer(nfnl_ct_hook)) {
1283#ifdef CONFIG_MODULES
1284			nfnl_unlock(NFNL_SUBSYS_QUEUE);
1285			request_module("ip_conntrack_netlink");
1286			nfnl_lock(NFNL_SUBSYS_QUEUE);
1287			if (rcu_access_pointer(nfnl_ct_hook))
1288				return -EAGAIN;
1289#endif
1290			return -EOPNOTSUPP;
1291		}
1292	}
1293
1294	rcu_read_lock();
1295	queue = instance_lookup(q, queue_num);
1296	if (queue && queue->peer_portid != NETLINK_CB(skb).portid) {
1297		ret = -EPERM;
1298		goto err_out_unlock;
1299	}
1300
1301	if (cmd != NULL) {
1302		switch (cmd->command) {
1303		case NFQNL_CFG_CMD_BIND:
1304			if (queue) {
1305				ret = -EBUSY;
1306				goto err_out_unlock;
1307			}
1308			queue = instance_create(q, queue_num,
1309						NETLINK_CB(skb).portid);
1310			if (IS_ERR(queue)) {
1311				ret = PTR_ERR(queue);
1312				goto err_out_unlock;
1313			}
1314			break;
1315		case NFQNL_CFG_CMD_UNBIND:
1316			if (!queue) {
1317				ret = -ENODEV;
1318				goto err_out_unlock;
1319			}
1320			instance_destroy(q, queue);
1321			goto err_out_unlock;
1322		case NFQNL_CFG_CMD_PF_BIND:
1323		case NFQNL_CFG_CMD_PF_UNBIND:
1324			break;
1325		default:
1326			ret = -ENOTSUPP;
1327			goto err_out_unlock;
1328		}
1329	}
1330
1331	if (!queue) {
1332		ret = -ENODEV;
1333		goto err_out_unlock;
1334	}
1335
1336	if (nfqa[NFQA_CFG_PARAMS]) {
1337		struct nfqnl_msg_config_params *params =
1338			nla_data(nfqa[NFQA_CFG_PARAMS]);
1339
1340		nfqnl_set_mode(queue, params->copy_mode,
1341				ntohl(params->copy_range));
1342	}
1343
1344	if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
1345		__be32 *queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
1346
1347		spin_lock_bh(&queue->lock);
1348		queue->queue_maxlen = ntohl(*queue_maxlen);
1349		spin_unlock_bh(&queue->lock);
1350	}
1351
1352	if (nfqa[NFQA_CFG_FLAGS]) {
1353		spin_lock_bh(&queue->lock);
1354		queue->flags &= ~mask;
1355		queue->flags |= flags & mask;
1356		spin_unlock_bh(&queue->lock);
1357	}
1358
1359err_out_unlock:
1360	rcu_read_unlock();
1361	return ret;
1362}
1363
1364static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
1365	[NFQNL_MSG_PACKET]	= {
1366		.call		= nfqnl_recv_unsupp,
1367		.type		= NFNL_CB_RCU,
1368		.attr_count	= NFQA_MAX,
1369	},
1370	[NFQNL_MSG_VERDICT]	= {
1371		.call		= nfqnl_recv_verdict,
1372		.type		= NFNL_CB_RCU,
1373		.attr_count	= NFQA_MAX,
1374		.policy		= nfqa_verdict_policy
1375	},
1376	[NFQNL_MSG_CONFIG]	= {
1377		.call		= nfqnl_recv_config,
1378		.type		= NFNL_CB_MUTEX,
1379		.attr_count	= NFQA_CFG_MAX,
1380		.policy		= nfqa_cfg_policy
1381	},
1382	[NFQNL_MSG_VERDICT_BATCH] = {
1383		.call		= nfqnl_recv_verdict_batch,
1384		.type		= NFNL_CB_RCU,
1385		.attr_count	= NFQA_MAX,
1386		.policy		= nfqa_verdict_batch_policy
1387	},
1388};
1389
1390static const struct nfnetlink_subsystem nfqnl_subsys = {
1391	.name		= "nf_queue",
1392	.subsys_id	= NFNL_SUBSYS_QUEUE,
1393	.cb_count	= NFQNL_MSG_MAX,
1394	.cb		= nfqnl_cb,
1395};
1396
1397#ifdef CONFIG_PROC_FS
1398struct iter_state {
1399	struct seq_net_private p;
1400	unsigned int bucket;
1401};
1402
1403static struct hlist_node *get_first(struct seq_file *seq)
1404{
1405	struct iter_state *st = seq->private;
1406	struct net *net;
1407	struct nfnl_queue_net *q;
1408
1409	if (!st)
1410		return NULL;
1411
1412	net = seq_file_net(seq);
1413	q = nfnl_queue_pernet(net);
1414	for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
1415		if (!hlist_empty(&q->instance_table[st->bucket]))
1416			return q->instance_table[st->bucket].first;
1417	}
1418	return NULL;
1419}
1420
1421static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
1422{
1423	struct iter_state *st = seq->private;
1424	struct net *net = seq_file_net(seq);
1425
1426	h = h->next;
1427	while (!h) {
1428		struct nfnl_queue_net *q;
1429
1430		if (++st->bucket >= INSTANCE_BUCKETS)
1431			return NULL;
1432
1433		q = nfnl_queue_pernet(net);
1434		h = q->instance_table[st->bucket].first;
1435	}
1436	return h;
1437}
1438
1439static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
1440{
1441	struct hlist_node *head;
1442	head = get_first(seq);
1443
1444	if (head)
1445		while (pos && (head = get_next(seq, head)))
1446			pos--;
1447	return pos ? NULL : head;
1448}
1449
1450static void *seq_start(struct seq_file *s, loff_t *pos)
1451	__acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1452{
1453	spin_lock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1454	return get_idx(s, *pos);
1455}
1456
1457static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
1458{
1459	(*pos)++;
1460	return get_next(s, v);
1461}
1462
1463static void seq_stop(struct seq_file *s, void *v)
1464	__releases(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1465{
1466	spin_unlock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1467}
1468
1469static int seq_show(struct seq_file *s, void *v)
1470{
1471	const struct nfqnl_instance *inst = v;
1472
1473	seq_printf(s, "%5u %6u %5u %1u %5u %5u %5u %8u %2d\n",
1474		   inst->queue_num,
1475		   inst->peer_portid, inst->queue_total,
1476		   inst->copy_mode, inst->copy_range,
1477		   inst->queue_dropped, inst->queue_user_dropped,
1478		   inst->id_sequence, 1);
1479	return 0;
1480}
1481
1482static const struct seq_operations nfqnl_seq_ops = {
1483	.start	= seq_start,
1484	.next	= seq_next,
1485	.stop	= seq_stop,
1486	.show	= seq_show,
1487};
1488#endif /* PROC_FS */
1489
1490static int __net_init nfnl_queue_net_init(struct net *net)
1491{
1492	unsigned int i;
1493	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1494
1495	for (i = 0; i < INSTANCE_BUCKETS; i++)
1496		INIT_HLIST_HEAD(&q->instance_table[i]);
1497
1498	spin_lock_init(&q->instances_lock);
1499
1500#ifdef CONFIG_PROC_FS
1501	if (!proc_create_net("nfnetlink_queue", 0440, net->nf.proc_netfilter,
1502			&nfqnl_seq_ops, sizeof(struct iter_state)))
1503		return -ENOMEM;
1504#endif
1505	nf_register_queue_handler(net, &nfqh);
1506	return 0;
1507}
1508
1509static void __net_exit nfnl_queue_net_exit(struct net *net)
1510{
1511	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1512	unsigned int i;
1513
1514	nf_unregister_queue_handler(net);
1515#ifdef CONFIG_PROC_FS
1516	remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter);
1517#endif
1518	for (i = 0; i < INSTANCE_BUCKETS; i++)
1519		WARN_ON_ONCE(!hlist_empty(&q->instance_table[i]));
1520}
1521
1522static void nfnl_queue_net_exit_batch(struct list_head *net_exit_list)
1523{
1524	synchronize_rcu();
1525}
1526
1527static struct pernet_operations nfnl_queue_net_ops = {
1528	.init		= nfnl_queue_net_init,
1529	.exit		= nfnl_queue_net_exit,
1530	.exit_batch	= nfnl_queue_net_exit_batch,
1531	.id		= &nfnl_queue_net_id,
1532	.size		= sizeof(struct nfnl_queue_net),
1533};
1534
1535static int __init nfnetlink_queue_init(void)
1536{
1537	int status;
1538
1539	status = register_pernet_subsys(&nfnl_queue_net_ops);
1540	if (status < 0) {
1541		pr_err("failed to register pernet ops\n");
1542		goto out;
1543	}
1544
1545	netlink_register_notifier(&nfqnl_rtnl_notifier);
1546	status = nfnetlink_subsys_register(&nfqnl_subsys);
1547	if (status < 0) {
1548		pr_err("failed to create netlink socket\n");
1549		goto cleanup_netlink_notifier;
1550	}
1551
1552	status = register_netdevice_notifier(&nfqnl_dev_notifier);
1553	if (status < 0) {
1554		pr_err("failed to register netdevice notifier\n");
1555		goto cleanup_netlink_subsys;
1556	}
1557
1558	return status;
1559
1560cleanup_netlink_subsys:
1561	nfnetlink_subsys_unregister(&nfqnl_subsys);
1562cleanup_netlink_notifier:
1563	netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1564	unregister_pernet_subsys(&nfnl_queue_net_ops);
1565out:
1566	return status;
1567}
1568
1569static void __exit nfnetlink_queue_fini(void)
1570{
1571	unregister_netdevice_notifier(&nfqnl_dev_notifier);
1572	nfnetlink_subsys_unregister(&nfqnl_subsys);
1573	netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1574	unregister_pernet_subsys(&nfnl_queue_net_ops);
1575
1576	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1577}
1578
1579MODULE_DESCRIPTION("netfilter packet queue handler");
1580MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1581MODULE_LICENSE("GPL");
1582MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1583
1584module_init(nfnetlink_queue_init);
1585module_exit(nfnetlink_queue_fini);
v5.9
   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 <net/sock.h>
  33#include <net/tcp_states.h>
  34#include <net/netfilter/nf_queue.h>
  35#include <net/netns/generic.h>
  36
  37#include <linux/atomic.h>
  38
  39#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
  40#include "../bridge/br_private.h"
  41#endif
  42
  43#if IS_ENABLED(CONFIG_NF_CONNTRACK)
  44#include <net/netfilter/nf_conntrack.h>
  45#endif
  46
  47#define NFQNL_QMAX_DEFAULT 1024
  48
  49/* We're using struct nlattr which has 16bit nla_len. Note that nla_len
  50 * includes the header length. Thus, the maximum packet length that we
  51 * support is 65531 bytes. We send truncated packets if the specified length
  52 * is larger than that.  Userspace can check for presence of NFQA_CAP_LEN
  53 * attribute to detect truncation.
  54 */
  55#define NFQNL_MAX_COPY_RANGE (0xffff - NLA_HDRLEN)
  56
  57struct nfqnl_instance {
  58	struct hlist_node hlist;		/* global list of queues */
  59	struct rcu_head rcu;
  60
  61	u32 peer_portid;
  62	unsigned int queue_maxlen;
  63	unsigned int copy_range;
  64	unsigned int queue_dropped;
  65	unsigned int queue_user_dropped;
  66
  67
  68	u_int16_t queue_num;			/* number of this queue */
  69	u_int8_t copy_mode;
  70	u_int32_t flags;			/* Set using NFQA_CFG_FLAGS */
  71/*
  72 * Following fields are dirtied for each queued packet,
  73 * keep them in same cache line if possible.
  74 */
  75	spinlock_t	lock	____cacheline_aligned_in_smp;
  76	unsigned int	queue_total;
  77	unsigned int	id_sequence;		/* 'sequence' of pkt ids */
  78	struct list_head queue_list;		/* packets in queue */
  79};
  80
  81typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
  82
  83static unsigned int nfnl_queue_net_id __read_mostly;
  84
  85#define INSTANCE_BUCKETS	16
  86struct nfnl_queue_net {
  87	spinlock_t instances_lock;
  88	struct hlist_head instance_table[INSTANCE_BUCKETS];
  89};
  90
  91static struct nfnl_queue_net *nfnl_queue_pernet(struct net *net)
  92{
  93	return net_generic(net, nfnl_queue_net_id);
  94}
  95
  96static inline u_int8_t instance_hashfn(u_int16_t queue_num)
  97{
  98	return ((queue_num >> 8) ^ queue_num) % INSTANCE_BUCKETS;
  99}
 100
 101static struct nfqnl_instance *
 102instance_lookup(struct nfnl_queue_net *q, u_int16_t queue_num)
 103{
 104	struct hlist_head *head;
 105	struct nfqnl_instance *inst;
 106
 107	head = &q->instance_table[instance_hashfn(queue_num)];
 108	hlist_for_each_entry_rcu(inst, head, hlist) {
 109		if (inst->queue_num == queue_num)
 110			return inst;
 111	}
 112	return NULL;
 113}
 114
 115static struct nfqnl_instance *
 116instance_create(struct nfnl_queue_net *q, u_int16_t queue_num, u32 portid)
 117{
 118	struct nfqnl_instance *inst;
 119	unsigned int h;
 120	int err;
 121
 122	spin_lock(&q->instances_lock);
 123	if (instance_lookup(q, queue_num)) {
 124		err = -EEXIST;
 125		goto out_unlock;
 126	}
 127
 128	inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
 129	if (!inst) {
 130		err = -ENOMEM;
 131		goto out_unlock;
 132	}
 133
 134	inst->queue_num = queue_num;
 135	inst->peer_portid = portid;
 136	inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
 137	inst->copy_range = NFQNL_MAX_COPY_RANGE;
 138	inst->copy_mode = NFQNL_COPY_NONE;
 139	spin_lock_init(&inst->lock);
 140	INIT_LIST_HEAD(&inst->queue_list);
 141
 142	if (!try_module_get(THIS_MODULE)) {
 143		err = -EAGAIN;
 144		goto out_free;
 145	}
 146
 147	h = instance_hashfn(queue_num);
 148	hlist_add_head_rcu(&inst->hlist, &q->instance_table[h]);
 149
 150	spin_unlock(&q->instances_lock);
 151
 152	return inst;
 153
 154out_free:
 155	kfree(inst);
 156out_unlock:
 157	spin_unlock(&q->instances_lock);
 158	return ERR_PTR(err);
 159}
 160
 161static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
 162			unsigned long data);
 163
 164static void
 165instance_destroy_rcu(struct rcu_head *head)
 166{
 167	struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
 168						   rcu);
 169
 170	nfqnl_flush(inst, NULL, 0);
 171	kfree(inst);
 172	module_put(THIS_MODULE);
 173}
 174
 175static void
 176__instance_destroy(struct nfqnl_instance *inst)
 177{
 178	hlist_del_rcu(&inst->hlist);
 179	call_rcu(&inst->rcu, instance_destroy_rcu);
 180}
 181
 182static void
 183instance_destroy(struct nfnl_queue_net *q, struct nfqnl_instance *inst)
 184{
 185	spin_lock(&q->instances_lock);
 186	__instance_destroy(inst);
 187	spin_unlock(&q->instances_lock);
 188}
 189
 190static inline void
 191__enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 192{
 193       list_add_tail(&entry->list, &queue->queue_list);
 194       queue->queue_total++;
 195}
 196
 197static void
 198__dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 199{
 200	list_del(&entry->list);
 201	queue->queue_total--;
 202}
 203
 204static struct nf_queue_entry *
 205find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
 206{
 207	struct nf_queue_entry *entry = NULL, *i;
 208
 209	spin_lock_bh(&queue->lock);
 210
 211	list_for_each_entry(i, &queue->queue_list, list) {
 212		if (i->id == id) {
 213			entry = i;
 214			break;
 215		}
 216	}
 217
 218	if (entry)
 219		__dequeue_entry(queue, entry);
 220
 221	spin_unlock_bh(&queue->lock);
 222
 223	return entry;
 224}
 225
 226static void nfqnl_reinject(struct nf_queue_entry *entry, unsigned int verdict)
 227{
 228	struct nf_ct_hook *ct_hook;
 229	int err;
 230
 231	if (verdict == NF_ACCEPT ||
 232	    verdict == NF_REPEAT ||
 233	    verdict == NF_STOP) {
 234		rcu_read_lock();
 235		ct_hook = rcu_dereference(nf_ct_hook);
 236		if (ct_hook) {
 237			err = ct_hook->update(entry->state.net, entry->skb);
 238			if (err < 0)
 239				verdict = NF_DROP;
 240		}
 241		rcu_read_unlock();
 242	}
 243	nf_reinject(entry, verdict);
 244}
 245
 246static void
 247nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
 248{
 249	struct nf_queue_entry *entry, *next;
 250
 251	spin_lock_bh(&queue->lock);
 252	list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
 253		if (!cmpfn || cmpfn(entry, data)) {
 254			list_del(&entry->list);
 255			queue->queue_total--;
 256			nfqnl_reinject(entry, NF_DROP);
 257		}
 258	}
 259	spin_unlock_bh(&queue->lock);
 260}
 261
 262static int
 263nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
 264		      bool csum_verify)
 265{
 266	__u32 flags = 0;
 267
 268	if (packet->ip_summed == CHECKSUM_PARTIAL)
 269		flags = NFQA_SKB_CSUMNOTREADY;
 270	else if (csum_verify)
 271		flags = NFQA_SKB_CSUM_NOTVERIFIED;
 272
 273	if (skb_is_gso(packet))
 274		flags |= NFQA_SKB_GSO;
 275
 276	return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
 277}
 278
 279static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
 280{
 281	const struct cred *cred;
 282
 283	if (!sk_fullsock(sk))
 284		return 0;
 285
 286	read_lock_bh(&sk->sk_callback_lock);
 287	if (sk->sk_socket && sk->sk_socket->file) {
 288		cred = sk->sk_socket->file->f_cred;
 289		if (nla_put_be32(skb, NFQA_UID,
 290		    htonl(from_kuid_munged(&init_user_ns, cred->fsuid))))
 291			goto nla_put_failure;
 292		if (nla_put_be32(skb, NFQA_GID,
 293		    htonl(from_kgid_munged(&init_user_ns, cred->fsgid))))
 294			goto nla_put_failure;
 295	}
 296	read_unlock_bh(&sk->sk_callback_lock);
 297	return 0;
 298
 299nla_put_failure:
 300	read_unlock_bh(&sk->sk_callback_lock);
 301	return -1;
 302}
 303
 304static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
 305{
 306	u32 seclen = 0;
 307#if IS_ENABLED(CONFIG_NETWORK_SECMARK)
 308	if (!skb || !sk_fullsock(skb->sk))
 309		return 0;
 310
 311	read_lock_bh(&skb->sk->sk_callback_lock);
 312
 313	if (skb->secmark)
 314		security_secid_to_secctx(skb->secmark, secdata, &seclen);
 315
 316	read_unlock_bh(&skb->sk->sk_callback_lock);
 317#endif
 318	return seclen;
 319}
 320
 321static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
 322{
 323	struct sk_buff *entskb = entry->skb;
 324	u32 nlalen = 0;
 325
 326	if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
 327		return 0;
 328
 329	if (skb_vlan_tag_present(entskb))
 330		nlalen += nla_total_size(nla_total_size(sizeof(__be16)) +
 331					 nla_total_size(sizeof(__be16)));
 332
 333	if (entskb->network_header > entskb->mac_header)
 334		nlalen += nla_total_size((entskb->network_header -
 335					  entskb->mac_header));
 336
 337	return nlalen;
 338}
 339
 340static int nfqnl_put_bridge(struct nf_queue_entry *entry, struct sk_buff *skb)
 341{
 342	struct sk_buff *entskb = entry->skb;
 343
 344	if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
 345		return 0;
 346
 347	if (skb_vlan_tag_present(entskb)) {
 348		struct nlattr *nest;
 349
 350		nest = nla_nest_start(skb, NFQA_VLAN);
 351		if (!nest)
 352			goto nla_put_failure;
 353
 354		if (nla_put_be16(skb, NFQA_VLAN_TCI, htons(entskb->vlan_tci)) ||
 355		    nla_put_be16(skb, NFQA_VLAN_PROTO, entskb->vlan_proto))
 356			goto nla_put_failure;
 357
 358		nla_nest_end(skb, nest);
 359	}
 360
 361	if (entskb->mac_header < entskb->network_header) {
 362		int len = (int)(entskb->network_header - entskb->mac_header);
 363
 364		if (nla_put(skb, NFQA_L2HDR, len, skb_mac_header(entskb)))
 365			goto nla_put_failure;
 366	}
 367
 368	return 0;
 369
 370nla_put_failure:
 371	return -1;
 372}
 373
 374static struct sk_buff *
 375nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 376			   struct nf_queue_entry *entry,
 377			   __be32 **packet_id_ptr)
 378{
 379	size_t size;
 380	size_t data_len = 0, cap_len = 0;
 381	unsigned int hlen = 0;
 382	struct sk_buff *skb;
 383	struct nlattr *nla;
 384	struct nfqnl_msg_packet_hdr *pmsg;
 385	struct nlmsghdr *nlh;
 386	struct nfgenmsg *nfmsg;
 387	struct sk_buff *entskb = entry->skb;
 388	struct net_device *indev;
 389	struct net_device *outdev;
 390	struct nf_conn *ct = NULL;
 391	enum ip_conntrack_info ctinfo;
 392	struct nfnl_ct_hook *nfnl_ct;
 393	bool csum_verify;
 394	char *secdata = NULL;
 395	u32 seclen = 0;
 396
 397	size = nlmsg_total_size(sizeof(struct nfgenmsg))
 398		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
 399		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 400		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 401#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 402		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 403		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 404#endif
 405		+ nla_total_size(sizeof(u_int32_t))	/* mark */
 406		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
 407		+ nla_total_size(sizeof(u_int32_t))	/* skbinfo */
 408		+ nla_total_size(sizeof(u_int32_t));	/* cap_len */
 409
 410	if (entskb->tstamp)
 411		size += nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
 412
 413	size += nfqnl_get_bridge_size(entry);
 414
 415	if (entry->state.hook <= NF_INET_FORWARD ||
 416	   (entry->state.hook == NF_INET_POST_ROUTING && entskb->sk == NULL))
 417		csum_verify = !skb_csum_unnecessary(entskb);
 418	else
 419		csum_verify = false;
 420
 421	outdev = entry->state.out;
 422
 423	switch ((enum nfqnl_config_mode)READ_ONCE(queue->copy_mode)) {
 424	case NFQNL_COPY_META:
 425	case NFQNL_COPY_NONE:
 426		break;
 427
 428	case NFQNL_COPY_PACKET:
 429		if (!(queue->flags & NFQA_CFG_F_GSO) &&
 430		    entskb->ip_summed == CHECKSUM_PARTIAL &&
 431		    skb_checksum_help(entskb))
 432			return NULL;
 433
 434		data_len = READ_ONCE(queue->copy_range);
 435		if (data_len > entskb->len)
 436			data_len = entskb->len;
 437
 438		hlen = skb_zerocopy_headlen(entskb);
 439		hlen = min_t(unsigned int, hlen, data_len);
 440		size += sizeof(struct nlattr) + hlen;
 441		cap_len = entskb->len;
 442		break;
 443	}
 444
 445	nfnl_ct = rcu_dereference(nfnl_ct_hook);
 446
 
 447	if (queue->flags & NFQA_CFG_F_CONNTRACK) {
 448		if (nfnl_ct != NULL) {
 449			ct = nfnl_ct->get_ct(entskb, &ctinfo);
 450			if (ct != NULL)
 451				size += nfnl_ct->build_size(ct);
 452		}
 453	}
 
 454
 455	if (queue->flags & NFQA_CFG_F_UID_GID) {
 456		size += (nla_total_size(sizeof(u_int32_t))	/* uid */
 457			+ nla_total_size(sizeof(u_int32_t)));	/* gid */
 458	}
 459
 460	if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
 461		seclen = nfqnl_get_sk_secctx(entskb, &secdata);
 462		if (seclen)
 463			size += nla_total_size(seclen);
 464	}
 465
 466	skb = alloc_skb(size, GFP_ATOMIC);
 467	if (!skb) {
 468		skb_tx_error(entskb);
 469		goto nlmsg_failure;
 470	}
 471
 472	nlh = nlmsg_put(skb, 0, 0,
 473			nfnl_msg_type(NFNL_SUBSYS_QUEUE, NFQNL_MSG_PACKET),
 474			sizeof(struct nfgenmsg), 0);
 
 475	if (!nlh) {
 476		skb_tx_error(entskb);
 477		kfree_skb(skb);
 478		goto nlmsg_failure;
 479	}
 480	nfmsg = nlmsg_data(nlh);
 481	nfmsg->nfgen_family = entry->state.pf;
 482	nfmsg->version = NFNETLINK_V0;
 483	nfmsg->res_id = htons(queue->queue_num);
 484
 485	nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
 486	pmsg = nla_data(nla);
 487	pmsg->hw_protocol	= entskb->protocol;
 488	pmsg->hook		= entry->state.hook;
 489	*packet_id_ptr		= &pmsg->packet_id;
 490
 491	indev = entry->state.in;
 492	if (indev) {
 493#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 494		if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
 495			goto nla_put_failure;
 496#else
 497		if (entry->state.pf == PF_BRIDGE) {
 498			/* Case 1: indev is physical input device, we need to
 499			 * look for bridge group (when called from
 500			 * netfilter_bridge) */
 501			if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 502					 htonl(indev->ifindex)) ||
 503			/* this is the bridge group "brX" */
 504			/* rcu_read_lock()ed by __nf_queue */
 505			    nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 506					 htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
 507				goto nla_put_failure;
 508		} else {
 509			int physinif;
 510
 511			/* Case 2: indev is bridge group, we need to look for
 512			 * physical device (when called from ipv4) */
 513			if (nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 514					 htonl(indev->ifindex)))
 515				goto nla_put_failure;
 516
 517			physinif = nf_bridge_get_physinif(entskb);
 518			if (physinif &&
 519			    nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 520					 htonl(physinif)))
 521				goto nla_put_failure;
 522		}
 523#endif
 524	}
 525
 526	if (outdev) {
 527#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 528		if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
 529			goto nla_put_failure;
 530#else
 531		if (entry->state.pf == PF_BRIDGE) {
 532			/* Case 1: outdev is physical output device, we need to
 533			 * look for bridge group (when called from
 534			 * netfilter_bridge) */
 535			if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 536					 htonl(outdev->ifindex)) ||
 537			/* this is the bridge group "brX" */
 538			/* rcu_read_lock()ed by __nf_queue */
 539			    nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 540					 htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
 541				goto nla_put_failure;
 542		} else {
 543			int physoutif;
 544
 545			/* Case 2: outdev is bridge group, we need to look for
 546			 * physical output device (when called from ipv4) */
 547			if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 548					 htonl(outdev->ifindex)))
 549				goto nla_put_failure;
 550
 551			physoutif = nf_bridge_get_physoutif(entskb);
 552			if (physoutif &&
 553			    nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 554					 htonl(physoutif)))
 555				goto nla_put_failure;
 556		}
 557#endif
 558	}
 559
 560	if (entskb->mark &&
 561	    nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark)))
 562		goto nla_put_failure;
 563
 564	if (indev && entskb->dev &&
 565	    entskb->mac_header != entskb->network_header) {
 566		struct nfqnl_msg_packet_hw phw;
 567		int len;
 568
 569		memset(&phw, 0, sizeof(phw));
 570		len = dev_parse_header(entskb, phw.hw_addr);
 571		if (len) {
 572			phw.hw_addrlen = htons(len);
 573			if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw))
 574				goto nla_put_failure;
 575		}
 576	}
 577
 578	if (nfqnl_put_bridge(entry, skb) < 0)
 579		goto nla_put_failure;
 580
 581	if (entry->state.hook <= NF_INET_FORWARD && entskb->tstamp) {
 582		struct nfqnl_msg_packet_timestamp ts;
 583		struct timespec64 kts = ktime_to_timespec64(entskb->tstamp);
 584
 585		ts.sec = cpu_to_be64(kts.tv_sec);
 586		ts.usec = cpu_to_be64(kts.tv_nsec / NSEC_PER_USEC);
 587
 588		if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
 589			goto nla_put_failure;
 590	}
 591
 592	if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk &&
 593	    nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)
 594		goto nla_put_failure;
 595
 596	if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
 597		goto nla_put_failure;
 598
 599	if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
 600		goto nla_put_failure;
 601
 602	if (cap_len > data_len &&
 603	    nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len)))
 604		goto nla_put_failure;
 605
 606	if (nfqnl_put_packet_info(skb, entskb, csum_verify))
 607		goto nla_put_failure;
 608
 609	if (data_len) {
 610		struct nlattr *nla;
 611
 612		if (skb_tailroom(skb) < sizeof(*nla) + hlen)
 613			goto nla_put_failure;
 614
 615		nla = skb_put(skb, sizeof(*nla));
 616		nla->nla_type = NFQA_PAYLOAD;
 617		nla->nla_len = nla_attr_size(data_len);
 618
 619		if (skb_zerocopy(skb, entskb, data_len, hlen))
 620			goto nla_put_failure;
 621	}
 622
 623	nlh->nlmsg_len = skb->len;
 624	if (seclen)
 625		security_release_secctx(secdata, seclen);
 626	return skb;
 627
 628nla_put_failure:
 629	skb_tx_error(entskb);
 630	kfree_skb(skb);
 631	net_err_ratelimited("nf_queue: error creating packet message\n");
 632nlmsg_failure:
 633	if (seclen)
 634		security_release_secctx(secdata, seclen);
 635	return NULL;
 636}
 637
 638static bool nf_ct_drop_unconfirmed(const struct nf_queue_entry *entry)
 639{
 640#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 641	static const unsigned long flags = IPS_CONFIRMED | IPS_DYING;
 642	const struct nf_conn *ct = (void *)skb_nfct(entry->skb);
 643
 644	if (ct && ((ct->status & flags) == IPS_DYING))
 645		return true;
 646#endif
 647	return false;
 648}
 649
 650static int
 651__nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue,
 652			struct nf_queue_entry *entry)
 653{
 654	struct sk_buff *nskb;
 655	int err = -ENOBUFS;
 656	__be32 *packet_id_ptr;
 657	int failopen = 0;
 658
 659	nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr);
 660	if (nskb == NULL) {
 661		err = -ENOMEM;
 662		goto err_out;
 663	}
 664	spin_lock_bh(&queue->lock);
 665
 666	if (nf_ct_drop_unconfirmed(entry))
 667		goto err_out_free_nskb;
 668
 669	if (queue->queue_total >= queue->queue_maxlen) {
 670		if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 671			failopen = 1;
 672			err = 0;
 673		} else {
 674			queue->queue_dropped++;
 675			net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
 676					     queue->queue_total);
 677		}
 678		goto err_out_free_nskb;
 679	}
 680	entry->id = ++queue->id_sequence;
 681	*packet_id_ptr = htonl(entry->id);
 682
 683	/* nfnetlink_unicast will either free the nskb or add it to a socket */
 684	err = nfnetlink_unicast(nskb, net, queue->peer_portid);
 685	if (err < 0) {
 686		if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 687			failopen = 1;
 688			err = 0;
 689		} else {
 690			queue->queue_user_dropped++;
 691		}
 692		goto err_out_unlock;
 693	}
 694
 695	__enqueue_entry(queue, entry);
 696
 697	spin_unlock_bh(&queue->lock);
 698	return 0;
 699
 700err_out_free_nskb:
 701	kfree_skb(nskb);
 702err_out_unlock:
 703	spin_unlock_bh(&queue->lock);
 704	if (failopen)
 705		nfqnl_reinject(entry, NF_ACCEPT);
 706err_out:
 707	return err;
 708}
 709
 710static struct nf_queue_entry *
 711nf_queue_entry_dup(struct nf_queue_entry *e)
 712{
 713	struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC);
 714	if (entry)
 715		nf_queue_entry_get_refs(entry);
 716	return entry;
 717}
 718
 719#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 720/* When called from bridge netfilter, skb->data must point to MAC header
 721 * before calling skb_gso_segment(). Else, original MAC header is lost
 722 * and segmented skbs will be sent to wrong destination.
 723 */
 724static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
 725{
 726	if (nf_bridge_info_get(skb))
 727		__skb_push(skb, skb->network_header - skb->mac_header);
 728}
 729
 730static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
 731{
 732	if (nf_bridge_info_get(skb))
 733		__skb_pull(skb, skb->network_header - skb->mac_header);
 734}
 735#else
 736#define nf_bridge_adjust_skb_data(s) do {} while (0)
 737#define nf_bridge_adjust_segmented_data(s) do {} while (0)
 738#endif
 739
 740static int
 741__nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue,
 742			   struct sk_buff *skb, struct nf_queue_entry *entry)
 743{
 744	int ret = -ENOMEM;
 745	struct nf_queue_entry *entry_seg;
 746
 747	nf_bridge_adjust_segmented_data(skb);
 748
 749	if (skb->next == NULL) { /* last packet, no need to copy entry */
 750		struct sk_buff *gso_skb = entry->skb;
 751		entry->skb = skb;
 752		ret = __nfqnl_enqueue_packet(net, queue, entry);
 753		if (ret)
 754			entry->skb = gso_skb;
 755		return ret;
 756	}
 757
 758	skb_mark_not_on_list(skb);
 759
 760	entry_seg = nf_queue_entry_dup(entry);
 761	if (entry_seg) {
 762		entry_seg->skb = skb;
 763		ret = __nfqnl_enqueue_packet(net, queue, entry_seg);
 764		if (ret)
 765			nf_queue_entry_free(entry_seg);
 766	}
 767	return ret;
 768}
 769
 770static int
 771nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 772{
 773	unsigned int queued;
 774	struct nfqnl_instance *queue;
 775	struct sk_buff *skb, *segs, *nskb;
 776	int err = -ENOBUFS;
 777	struct net *net = entry->state.net;
 778	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 779
 780	/* rcu_read_lock()ed by nf_hook_thresh */
 781	queue = instance_lookup(q, queuenum);
 782	if (!queue)
 783		return -ESRCH;
 784
 785	if (queue->copy_mode == NFQNL_COPY_NONE)
 786		return -EINVAL;
 787
 788	skb = entry->skb;
 789
 790	switch (entry->state.pf) {
 791	case NFPROTO_IPV4:
 792		skb->protocol = htons(ETH_P_IP);
 793		break;
 794	case NFPROTO_IPV6:
 795		skb->protocol = htons(ETH_P_IPV6);
 796		break;
 797	}
 798
 799	if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb))
 800		return __nfqnl_enqueue_packet(net, queue, entry);
 801
 802	nf_bridge_adjust_skb_data(skb);
 803	segs = skb_gso_segment(skb, 0);
 804	/* Does not use PTR_ERR to limit the number of error codes that can be
 805	 * returned by nf_queue.  For instance, callers rely on -ESRCH to
 806	 * mean 'ignore this hook'.
 807	 */
 808	if (IS_ERR_OR_NULL(segs))
 809		goto out_err;
 810	queued = 0;
 811	err = 0;
 812	skb_list_walk_safe(segs, segs, nskb) {
 813		if (err == 0)
 814			err = __nfqnl_enqueue_packet_gso(net, queue,
 815							segs, entry);
 816		if (err == 0)
 817			queued++;
 818		else
 819			kfree_skb(segs);
 820	}
 821
 822	if (queued) {
 823		if (err) /* some segments are already queued */
 824			nf_queue_entry_free(entry);
 825		kfree_skb(skb);
 826		return 0;
 827	}
 828 out_err:
 829	nf_bridge_adjust_segmented_data(skb);
 830	return err;
 831}
 832
 833static int
 834nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff)
 835{
 836	struct sk_buff *nskb;
 837
 838	if (diff < 0) {
 839		if (pskb_trim(e->skb, data_len))
 840			return -ENOMEM;
 841	} else if (diff > 0) {
 842		if (data_len > 0xFFFF)
 843			return -EINVAL;
 844		if (diff > skb_tailroom(e->skb)) {
 845			nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
 846					       diff, GFP_ATOMIC);
 847			if (!nskb)
 848				return -ENOMEM;
 849			kfree_skb(e->skb);
 850			e->skb = nskb;
 851		}
 852		skb_put(e->skb, diff);
 853	}
 854	if (skb_ensure_writable(e->skb, data_len))
 855		return -ENOMEM;
 856	skb_copy_to_linear_data(e->skb, data, data_len);
 857	e->skb->ip_summed = CHECKSUM_NONE;
 858	return 0;
 859}
 860
 861static int
 862nfqnl_set_mode(struct nfqnl_instance *queue,
 863	       unsigned char mode, unsigned int range)
 864{
 865	int status = 0;
 866
 867	spin_lock_bh(&queue->lock);
 868	switch (mode) {
 869	case NFQNL_COPY_NONE:
 870	case NFQNL_COPY_META:
 871		queue->copy_mode = mode;
 872		queue->copy_range = 0;
 873		break;
 874
 875	case NFQNL_COPY_PACKET:
 876		queue->copy_mode = mode;
 877		if (range == 0 || range > NFQNL_MAX_COPY_RANGE)
 878			queue->copy_range = NFQNL_MAX_COPY_RANGE;
 879		else
 880			queue->copy_range = range;
 881		break;
 882
 883	default:
 884		status = -EINVAL;
 885
 886	}
 887	spin_unlock_bh(&queue->lock);
 888
 889	return status;
 890}
 891
 892static int
 893dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
 894{
 895#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 896	int physinif, physoutif;
 897
 898	physinif = nf_bridge_get_physinif(entry->skb);
 899	physoutif = nf_bridge_get_physoutif(entry->skb);
 900
 901	if (physinif == ifindex || physoutif == ifindex)
 902		return 1;
 903#endif
 904	if (entry->state.in)
 905		if (entry->state.in->ifindex == ifindex)
 906			return 1;
 907	if (entry->state.out)
 908		if (entry->state.out->ifindex == ifindex)
 909			return 1;
 910
 911	return 0;
 912}
 913
 914/* drop all packets with either indev or outdev == ifindex from all queue
 915 * instances */
 916static void
 917nfqnl_dev_drop(struct net *net, int ifindex)
 918{
 919	int i;
 920	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 921
 922	rcu_read_lock();
 923
 924	for (i = 0; i < INSTANCE_BUCKETS; i++) {
 925		struct nfqnl_instance *inst;
 926		struct hlist_head *head = &q->instance_table[i];
 927
 928		hlist_for_each_entry_rcu(inst, head, hlist)
 929			nfqnl_flush(inst, dev_cmp, ifindex);
 930	}
 931
 932	rcu_read_unlock();
 933}
 934
 935static int
 936nfqnl_rcv_dev_event(struct notifier_block *this,
 937		    unsigned long event, void *ptr)
 938{
 939	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 940
 941	/* Drop any packets associated with the downed device */
 942	if (event == NETDEV_DOWN)
 943		nfqnl_dev_drop(dev_net(dev), dev->ifindex);
 944	return NOTIFY_DONE;
 945}
 946
 947static struct notifier_block nfqnl_dev_notifier = {
 948	.notifier_call	= nfqnl_rcv_dev_event,
 949};
 950
 951static void nfqnl_nf_hook_drop(struct net *net)
 952{
 953	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 954	int i;
 955
 956	for (i = 0; i < INSTANCE_BUCKETS; i++) {
 957		struct nfqnl_instance *inst;
 958		struct hlist_head *head = &q->instance_table[i];
 959
 960		hlist_for_each_entry_rcu(inst, head, hlist)
 961			nfqnl_flush(inst, NULL, 0);
 962	}
 963}
 964
 965static int
 966nfqnl_rcv_nl_event(struct notifier_block *this,
 967		   unsigned long event, void *ptr)
 968{
 969	struct netlink_notify *n = ptr;
 970	struct nfnl_queue_net *q = nfnl_queue_pernet(n->net);
 971
 972	if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
 973		int i;
 974
 975		/* destroy all instances for this portid */
 976		spin_lock(&q->instances_lock);
 977		for (i = 0; i < INSTANCE_BUCKETS; i++) {
 978			struct hlist_node *t2;
 979			struct nfqnl_instance *inst;
 980			struct hlist_head *head = &q->instance_table[i];
 981
 982			hlist_for_each_entry_safe(inst, t2, head, hlist) {
 983				if (n->portid == inst->peer_portid)
 984					__instance_destroy(inst);
 985			}
 986		}
 987		spin_unlock(&q->instances_lock);
 988	}
 989	return NOTIFY_DONE;
 990}
 991
 992static struct notifier_block nfqnl_rtnl_notifier = {
 993	.notifier_call	= nfqnl_rcv_nl_event,
 994};
 995
 996static const struct nla_policy nfqa_vlan_policy[NFQA_VLAN_MAX + 1] = {
 997	[NFQA_VLAN_TCI]		= { .type = NLA_U16},
 998	[NFQA_VLAN_PROTO]	= { .type = NLA_U16},
 999};
1000
1001static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
1002	[NFQA_VERDICT_HDR]	= { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
1003	[NFQA_MARK]		= { .type = NLA_U32 },
1004	[NFQA_PAYLOAD]		= { .type = NLA_UNSPEC },
1005	[NFQA_CT]		= { .type = NLA_UNSPEC },
1006	[NFQA_EXP]		= { .type = NLA_UNSPEC },
1007	[NFQA_VLAN]		= { .type = NLA_NESTED },
1008};
1009
1010static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
1011	[NFQA_VERDICT_HDR]	= { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
1012	[NFQA_MARK]		= { .type = NLA_U32 },
1013};
1014
1015static struct nfqnl_instance *
1016verdict_instance_lookup(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid)
1017{
1018	struct nfqnl_instance *queue;
1019
1020	queue = instance_lookup(q, queue_num);
1021	if (!queue)
1022		return ERR_PTR(-ENODEV);
1023
1024	if (queue->peer_portid != nlportid)
1025		return ERR_PTR(-EPERM);
1026
1027	return queue;
1028}
1029
1030static struct nfqnl_msg_verdict_hdr*
1031verdicthdr_get(const struct nlattr * const nfqa[])
1032{
1033	struct nfqnl_msg_verdict_hdr *vhdr;
1034	unsigned int verdict;
1035
1036	if (!nfqa[NFQA_VERDICT_HDR])
1037		return NULL;
1038
1039	vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
1040	verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
1041	if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
1042		return NULL;
1043	return vhdr;
1044}
1045
1046static int nfq_id_after(unsigned int id, unsigned int max)
1047{
1048	return (int)(id - max) > 0;
1049}
1050
1051static int nfqnl_recv_verdict_batch(struct net *net, struct sock *ctnl,
1052				    struct sk_buff *skb,
1053				    const struct nlmsghdr *nlh,
1054			            const struct nlattr * const nfqa[],
1055				    struct netlink_ext_ack *extack)
1056{
1057	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
 
1058	struct nf_queue_entry *entry, *tmp;
1059	unsigned int verdict, maxid;
1060	struct nfqnl_msg_verdict_hdr *vhdr;
1061	struct nfqnl_instance *queue;
 
1062	LIST_HEAD(batch_list);
1063	u16 queue_num = ntohs(nfmsg->res_id);
1064	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1065
1066	queue = verdict_instance_lookup(q, queue_num,
1067					NETLINK_CB(skb).portid);
1068	if (IS_ERR(queue))
1069		return PTR_ERR(queue);
1070
1071	vhdr = verdicthdr_get(nfqa);
1072	if (!vhdr)
1073		return -EINVAL;
1074
1075	verdict = ntohl(vhdr->verdict);
1076	maxid = ntohl(vhdr->id);
1077
1078	spin_lock_bh(&queue->lock);
1079
1080	list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
1081		if (nfq_id_after(entry->id, maxid))
1082			break;
1083		__dequeue_entry(queue, entry);
1084		list_add_tail(&entry->list, &batch_list);
1085	}
1086
1087	spin_unlock_bh(&queue->lock);
1088
1089	if (list_empty(&batch_list))
1090		return -ENOENT;
1091
1092	list_for_each_entry_safe(entry, tmp, &batch_list, list) {
1093		if (nfqa[NFQA_MARK])
1094			entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1095
1096		nfqnl_reinject(entry, verdict);
1097	}
1098	return 0;
1099}
1100
1101static struct nf_conn *nfqnl_ct_parse(struct nfnl_ct_hook *nfnl_ct,
1102				      const struct nlmsghdr *nlh,
1103				      const struct nlattr * const nfqa[],
1104				      struct nf_queue_entry *entry,
1105				      enum ip_conntrack_info *ctinfo)
1106{
 
1107	struct nf_conn *ct;
1108
1109	ct = nfnl_ct->get_ct(entry->skb, ctinfo);
1110	if (ct == NULL)
1111		return NULL;
1112
1113	if (nfnl_ct->parse(nfqa[NFQA_CT], ct) < 0)
1114		return NULL;
1115
1116	if (nfqa[NFQA_EXP])
1117		nfnl_ct->attach_expect(nfqa[NFQA_EXP], ct,
1118				      NETLINK_CB(entry->skb).portid,
1119				      nlmsg_report(nlh));
1120	return ct;
 
 
 
1121}
1122
1123static int nfqa_parse_bridge(struct nf_queue_entry *entry,
1124			     const struct nlattr * const nfqa[])
1125{
1126	if (nfqa[NFQA_VLAN]) {
1127		struct nlattr *tb[NFQA_VLAN_MAX + 1];
1128		int err;
1129
1130		err = nla_parse_nested_deprecated(tb, NFQA_VLAN_MAX,
1131						  nfqa[NFQA_VLAN],
1132						  nfqa_vlan_policy, NULL);
1133		if (err < 0)
1134			return err;
1135
1136		if (!tb[NFQA_VLAN_TCI] || !tb[NFQA_VLAN_PROTO])
1137			return -EINVAL;
1138
1139		__vlan_hwaccel_put_tag(entry->skb,
1140			nla_get_be16(tb[NFQA_VLAN_PROTO]),
1141			ntohs(nla_get_be16(tb[NFQA_VLAN_TCI])));
1142	}
1143
1144	if (nfqa[NFQA_L2HDR]) {
1145		int mac_header_len = entry->skb->network_header -
1146			entry->skb->mac_header;
1147
1148		if (mac_header_len != nla_len(nfqa[NFQA_L2HDR]))
1149			return -EINVAL;
1150		else if (mac_header_len > 0)
1151			memcpy(skb_mac_header(entry->skb),
1152			       nla_data(nfqa[NFQA_L2HDR]),
1153			       mac_header_len);
1154	}
1155
1156	return 0;
1157}
1158
1159static int nfqnl_recv_verdict(struct net *net, struct sock *ctnl,
1160			      struct sk_buff *skb,
1161			      const struct nlmsghdr *nlh,
1162			      const struct nlattr * const nfqa[],
1163			      struct netlink_ext_ack *extack)
1164{
1165	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1166	u_int16_t queue_num = ntohs(nfmsg->res_id);
1167	struct nfqnl_msg_verdict_hdr *vhdr;
 
1168	struct nfqnl_instance *queue;
1169	unsigned int verdict;
1170	struct nf_queue_entry *entry;
1171	enum ip_conntrack_info ctinfo;
1172	struct nfnl_ct_hook *nfnl_ct;
1173	struct nf_conn *ct = NULL;
1174	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1175	int err;
1176
1177	queue = verdict_instance_lookup(q, queue_num,
1178					NETLINK_CB(skb).portid);
1179	if (IS_ERR(queue))
1180		return PTR_ERR(queue);
1181
1182	vhdr = verdicthdr_get(nfqa);
1183	if (!vhdr)
1184		return -EINVAL;
1185
1186	verdict = ntohl(vhdr->verdict);
1187
1188	entry = find_dequeue_entry(queue, ntohl(vhdr->id));
1189	if (entry == NULL)
1190		return -ENOENT;
1191
1192	/* rcu lock already held from nfnl->call_rcu. */
1193	nfnl_ct = rcu_dereference(nfnl_ct_hook);
1194
1195	if (nfqa[NFQA_CT]) {
1196		if (nfnl_ct != NULL)
1197			ct = nfqnl_ct_parse(nfnl_ct, nlh, nfqa, entry, &ctinfo);
 
1198	}
1199
1200	if (entry->state.pf == PF_BRIDGE) {
1201		err = nfqa_parse_bridge(entry, nfqa);
1202		if (err < 0)
1203			return err;
1204	}
1205
1206	if (nfqa[NFQA_PAYLOAD]) {
1207		u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]);
1208		int diff = payload_len - entry->skb->len;
1209
1210		if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
1211				 payload_len, entry, diff) < 0)
1212			verdict = NF_DROP;
1213
1214		if (ct && diff)
1215			nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff);
1216	}
1217
1218	if (nfqa[NFQA_MARK])
1219		entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1220
1221	nfqnl_reinject(entry, verdict);
1222	return 0;
1223}
1224
1225static int nfqnl_recv_unsupp(struct net *net, struct sock *ctnl,
1226			     struct sk_buff *skb, const struct nlmsghdr *nlh,
1227			     const struct nlattr * const nfqa[],
1228			     struct netlink_ext_ack *extack)
1229{
1230	return -ENOTSUPP;
1231}
1232
1233static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
1234	[NFQA_CFG_CMD]		= { .len = sizeof(struct nfqnl_msg_config_cmd) },
1235	[NFQA_CFG_PARAMS]	= { .len = sizeof(struct nfqnl_msg_config_params) },
1236	[NFQA_CFG_QUEUE_MAXLEN]	= { .type = NLA_U32 },
1237	[NFQA_CFG_MASK]		= { .type = NLA_U32 },
1238	[NFQA_CFG_FLAGS]	= { .type = NLA_U32 },
1239};
1240
1241static const struct nf_queue_handler nfqh = {
1242	.outfn		= nfqnl_enqueue_packet,
1243	.nf_hook_drop	= nfqnl_nf_hook_drop,
1244};
1245
1246static int nfqnl_recv_config(struct net *net, struct sock *ctnl,
1247			     struct sk_buff *skb, const struct nlmsghdr *nlh,
1248			     const struct nlattr * const nfqa[],
1249			     struct netlink_ext_ack *extack)
1250{
1251	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1252	u_int16_t queue_num = ntohs(nfmsg->res_id);
 
1253	struct nfqnl_instance *queue;
1254	struct nfqnl_msg_config_cmd *cmd = NULL;
1255	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1256	__u32 flags = 0, mask = 0;
1257	int ret = 0;
1258
1259	if (nfqa[NFQA_CFG_CMD]) {
1260		cmd = nla_data(nfqa[NFQA_CFG_CMD]);
1261
1262		/* Obsolete commands without queue context */
1263		switch (cmd->command) {
1264		case NFQNL_CFG_CMD_PF_BIND: return 0;
1265		case NFQNL_CFG_CMD_PF_UNBIND: return 0;
1266		}
1267	}
1268
1269	/* Check if we support these flags in first place, dependencies should
1270	 * be there too not to break atomicity.
1271	 */
1272	if (nfqa[NFQA_CFG_FLAGS]) {
1273		if (!nfqa[NFQA_CFG_MASK]) {
1274			/* A mask is needed to specify which flags are being
1275			 * changed.
1276			 */
1277			return -EINVAL;
1278		}
1279
1280		flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
1281		mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
1282
1283		if (flags >= NFQA_CFG_F_MAX)
1284			return -EOPNOTSUPP;
1285
1286#if !IS_ENABLED(CONFIG_NETWORK_SECMARK)
1287		if (flags & mask & NFQA_CFG_F_SECCTX)
1288			return -EOPNOTSUPP;
1289#endif
1290		if ((flags & mask & NFQA_CFG_F_CONNTRACK) &&
1291		    !rcu_access_pointer(nfnl_ct_hook)) {
1292#ifdef CONFIG_MODULES
1293			nfnl_unlock(NFNL_SUBSYS_QUEUE);
1294			request_module("ip_conntrack_netlink");
1295			nfnl_lock(NFNL_SUBSYS_QUEUE);
1296			if (rcu_access_pointer(nfnl_ct_hook))
1297				return -EAGAIN;
1298#endif
1299			return -EOPNOTSUPP;
1300		}
1301	}
1302
1303	rcu_read_lock();
1304	queue = instance_lookup(q, queue_num);
1305	if (queue && queue->peer_portid != NETLINK_CB(skb).portid) {
1306		ret = -EPERM;
1307		goto err_out_unlock;
1308	}
1309
1310	if (cmd != NULL) {
1311		switch (cmd->command) {
1312		case NFQNL_CFG_CMD_BIND:
1313			if (queue) {
1314				ret = -EBUSY;
1315				goto err_out_unlock;
1316			}
1317			queue = instance_create(q, queue_num,
1318						NETLINK_CB(skb).portid);
1319			if (IS_ERR(queue)) {
1320				ret = PTR_ERR(queue);
1321				goto err_out_unlock;
1322			}
1323			break;
1324		case NFQNL_CFG_CMD_UNBIND:
1325			if (!queue) {
1326				ret = -ENODEV;
1327				goto err_out_unlock;
1328			}
1329			instance_destroy(q, queue);
1330			goto err_out_unlock;
1331		case NFQNL_CFG_CMD_PF_BIND:
1332		case NFQNL_CFG_CMD_PF_UNBIND:
1333			break;
1334		default:
1335			ret = -ENOTSUPP;
1336			goto err_out_unlock;
1337		}
1338	}
1339
1340	if (!queue) {
1341		ret = -ENODEV;
1342		goto err_out_unlock;
1343	}
1344
1345	if (nfqa[NFQA_CFG_PARAMS]) {
1346		struct nfqnl_msg_config_params *params =
1347			nla_data(nfqa[NFQA_CFG_PARAMS]);
1348
1349		nfqnl_set_mode(queue, params->copy_mode,
1350				ntohl(params->copy_range));
1351	}
1352
1353	if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
1354		__be32 *queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
1355
1356		spin_lock_bh(&queue->lock);
1357		queue->queue_maxlen = ntohl(*queue_maxlen);
1358		spin_unlock_bh(&queue->lock);
1359	}
1360
1361	if (nfqa[NFQA_CFG_FLAGS]) {
1362		spin_lock_bh(&queue->lock);
1363		queue->flags &= ~mask;
1364		queue->flags |= flags & mask;
1365		spin_unlock_bh(&queue->lock);
1366	}
1367
1368err_out_unlock:
1369	rcu_read_unlock();
1370	return ret;
1371}
1372
1373static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
1374	[NFQNL_MSG_PACKET]	= { .call_rcu = nfqnl_recv_unsupp,
1375				    .attr_count = NFQA_MAX, },
1376	[NFQNL_MSG_VERDICT]	= { .call_rcu = nfqnl_recv_verdict,
1377				    .attr_count = NFQA_MAX,
1378				    .policy = nfqa_verdict_policy },
1379	[NFQNL_MSG_CONFIG]	= { .call = nfqnl_recv_config,
1380				    .attr_count = NFQA_CFG_MAX,
1381				    .policy = nfqa_cfg_policy },
1382	[NFQNL_MSG_VERDICT_BATCH]={ .call_rcu = nfqnl_recv_verdict_batch,
1383				    .attr_count = NFQA_MAX,
1384				    .policy = nfqa_verdict_batch_policy },
 
 
 
 
 
 
 
 
 
 
 
 
1385};
1386
1387static const struct nfnetlink_subsystem nfqnl_subsys = {
1388	.name		= "nf_queue",
1389	.subsys_id	= NFNL_SUBSYS_QUEUE,
1390	.cb_count	= NFQNL_MSG_MAX,
1391	.cb		= nfqnl_cb,
1392};
1393
1394#ifdef CONFIG_PROC_FS
1395struct iter_state {
1396	struct seq_net_private p;
1397	unsigned int bucket;
1398};
1399
1400static struct hlist_node *get_first(struct seq_file *seq)
1401{
1402	struct iter_state *st = seq->private;
1403	struct net *net;
1404	struct nfnl_queue_net *q;
1405
1406	if (!st)
1407		return NULL;
1408
1409	net = seq_file_net(seq);
1410	q = nfnl_queue_pernet(net);
1411	for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
1412		if (!hlist_empty(&q->instance_table[st->bucket]))
1413			return q->instance_table[st->bucket].first;
1414	}
1415	return NULL;
1416}
1417
1418static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
1419{
1420	struct iter_state *st = seq->private;
1421	struct net *net = seq_file_net(seq);
1422
1423	h = h->next;
1424	while (!h) {
1425		struct nfnl_queue_net *q;
1426
1427		if (++st->bucket >= INSTANCE_BUCKETS)
1428			return NULL;
1429
1430		q = nfnl_queue_pernet(net);
1431		h = q->instance_table[st->bucket].first;
1432	}
1433	return h;
1434}
1435
1436static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
1437{
1438	struct hlist_node *head;
1439	head = get_first(seq);
1440
1441	if (head)
1442		while (pos && (head = get_next(seq, head)))
1443			pos--;
1444	return pos ? NULL : head;
1445}
1446
1447static void *seq_start(struct seq_file *s, loff_t *pos)
1448	__acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1449{
1450	spin_lock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1451	return get_idx(s, *pos);
1452}
1453
1454static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
1455{
1456	(*pos)++;
1457	return get_next(s, v);
1458}
1459
1460static void seq_stop(struct seq_file *s, void *v)
1461	__releases(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1462{
1463	spin_unlock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1464}
1465
1466static int seq_show(struct seq_file *s, void *v)
1467{
1468	const struct nfqnl_instance *inst = v;
1469
1470	seq_printf(s, "%5u %6u %5u %1u %5u %5u %5u %8u %2d\n",
1471		   inst->queue_num,
1472		   inst->peer_portid, inst->queue_total,
1473		   inst->copy_mode, inst->copy_range,
1474		   inst->queue_dropped, inst->queue_user_dropped,
1475		   inst->id_sequence, 1);
1476	return 0;
1477}
1478
1479static const struct seq_operations nfqnl_seq_ops = {
1480	.start	= seq_start,
1481	.next	= seq_next,
1482	.stop	= seq_stop,
1483	.show	= seq_show,
1484};
1485#endif /* PROC_FS */
1486
1487static int __net_init nfnl_queue_net_init(struct net *net)
1488{
1489	unsigned int i;
1490	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1491
1492	for (i = 0; i < INSTANCE_BUCKETS; i++)
1493		INIT_HLIST_HEAD(&q->instance_table[i]);
1494
1495	spin_lock_init(&q->instances_lock);
1496
1497#ifdef CONFIG_PROC_FS
1498	if (!proc_create_net("nfnetlink_queue", 0440, net->nf.proc_netfilter,
1499			&nfqnl_seq_ops, sizeof(struct iter_state)))
1500		return -ENOMEM;
1501#endif
1502	nf_register_queue_handler(net, &nfqh);
1503	return 0;
1504}
1505
1506static void __net_exit nfnl_queue_net_exit(struct net *net)
1507{
1508	struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1509	unsigned int i;
1510
1511	nf_unregister_queue_handler(net);
1512#ifdef CONFIG_PROC_FS
1513	remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter);
1514#endif
1515	for (i = 0; i < INSTANCE_BUCKETS; i++)
1516		WARN_ON_ONCE(!hlist_empty(&q->instance_table[i]));
1517}
1518
1519static void nfnl_queue_net_exit_batch(struct list_head *net_exit_list)
1520{
1521	synchronize_rcu();
1522}
1523
1524static struct pernet_operations nfnl_queue_net_ops = {
1525	.init		= nfnl_queue_net_init,
1526	.exit		= nfnl_queue_net_exit,
1527	.exit_batch	= nfnl_queue_net_exit_batch,
1528	.id		= &nfnl_queue_net_id,
1529	.size		= sizeof(struct nfnl_queue_net),
1530};
1531
1532static int __init nfnetlink_queue_init(void)
1533{
1534	int status;
1535
1536	status = register_pernet_subsys(&nfnl_queue_net_ops);
1537	if (status < 0) {
1538		pr_err("failed to register pernet ops\n");
1539		goto out;
1540	}
1541
1542	netlink_register_notifier(&nfqnl_rtnl_notifier);
1543	status = nfnetlink_subsys_register(&nfqnl_subsys);
1544	if (status < 0) {
1545		pr_err("failed to create netlink socket\n");
1546		goto cleanup_netlink_notifier;
1547	}
1548
1549	status = register_netdevice_notifier(&nfqnl_dev_notifier);
1550	if (status < 0) {
1551		pr_err("failed to register netdevice notifier\n");
1552		goto cleanup_netlink_subsys;
1553	}
1554
1555	return status;
1556
1557cleanup_netlink_subsys:
1558	nfnetlink_subsys_unregister(&nfqnl_subsys);
1559cleanup_netlink_notifier:
1560	netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1561	unregister_pernet_subsys(&nfnl_queue_net_ops);
1562out:
1563	return status;
1564}
1565
1566static void __exit nfnetlink_queue_fini(void)
1567{
1568	unregister_netdevice_notifier(&nfqnl_dev_notifier);
1569	nfnetlink_subsys_unregister(&nfqnl_subsys);
1570	netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1571	unregister_pernet_subsys(&nfnl_queue_net_ops);
1572
1573	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1574}
1575
1576MODULE_DESCRIPTION("netfilter packet queue handler");
1577MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1578MODULE_LICENSE("GPL");
1579MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1580
1581module_init(nfnetlink_queue_init);
1582module_exit(nfnetlink_queue_fini);