1/*
   2 * This is a module which is used for queueing packets and communicating with
   3 * userspace via nfnetlink.
   4 *
   5 * (C) 2005 by Harald Welte <laforge@netfilter.org>
   6 * (C) 2007 by Patrick McHardy <kaber@trash.net>
   7 *
   8 * Based on the old ipv4-only ip_queue.c:
   9 * (C) 2000-2002 James Morris <jmorris@intercode.com.au>
  10 * (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License version 2 as
  14 * published by the Free Software Foundation.
  15 *
  16 */
 
 
 
  17#include <linux/module.h>
  18#include <linux/skbuff.h>
  19#include <linux/init.h>
  20#include <linux/spinlock.h>
  21#include <linux/slab.h>
  22#include <linux/notifier.h>
  23#include <linux/netdevice.h>
  24#include <linux/netfilter.h>
  25#include <linux/proc_fs.h>
  26#include <linux/netfilter_ipv4.h>
  27#include <linux/netfilter_ipv6.h>
 
  28#include <linux/netfilter/nfnetlink.h>
  29#include <linux/netfilter/nfnetlink_queue.h>
 
  30#include <linux/list.h>
  31#include <net/sock.h>
 
  32#include <net/netfilter/nf_queue.h>
 
  33
  34#include <linux/atomic.h>
  35
  36#ifdef CONFIG_BRIDGE_NETFILTER
  37#include "../bridge/br_private.h"
  38#endif
  39
 
 
 
 
  40#define NFQNL_QMAX_DEFAULT 1024
  41
 
 
 
 
 
 
 
 
  42struct nfqnl_instance {
  43	struct hlist_node hlist;		/* global list of queues */
  44	struct rcu_head rcu;
  45
  46	int peer_pid;
  47	unsigned int queue_maxlen;
  48	unsigned int copy_range;
  49	unsigned int queue_dropped;
  50	unsigned int queue_user_dropped;
  51
  52
  53	u_int16_t queue_num;			/* number of this queue */
  54	u_int8_t copy_mode;
 
  55/*
  56 * Following fields are dirtied for each queued packet,
  57 * keep them in same cache line if possible.
  58 */
  59	spinlock_t	lock;
  60	unsigned int	queue_total;
  61	unsigned int	id_sequence;		/* 'sequence' of pkt ids */
  62	struct list_head queue_list;		/* packets in queue */
  63};
  64
  65typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
  66
  67static DEFINE_SPINLOCK(instances_lock);
  68
  69#define INSTANCE_BUCKETS	16
  70static struct hlist_head instance_table[INSTANCE_BUCKETS] __read_mostly;
 
 
 
 
 
 
 
 
  71
  72static inline u_int8_t instance_hashfn(u_int16_t queue_num)
  73{
  74	return ((queue_num >> 8) | queue_num) % INSTANCE_BUCKETS;
  75}
  76
  77static struct nfqnl_instance *
  78instance_lookup(u_int16_t queue_num)
  79{
  80	struct hlist_head *head;
  81	struct hlist_node *pos;
  82	struct nfqnl_instance *inst;
  83
  84	head = &instance_table[instance_hashfn(queue_num)];
  85	hlist_for_each_entry_rcu(inst, pos, head, hlist) {
  86		if (inst->queue_num == queue_num)
  87			return inst;
  88	}
  89	return NULL;
  90}
  91
  92static struct nfqnl_instance *
  93instance_create(u_int16_t queue_num, int pid)
  94{
  95	struct nfqnl_instance *inst;
  96	unsigned int h;
  97	int err;
  98
  99	spin_lock(&instances_lock);
 100	if (instance_lookup(queue_num)) {
 101		err = -EEXIST;
 102		goto out_unlock;
 103	}
 104
 105	inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
 106	if (!inst) {
 107		err = -ENOMEM;
 108		goto out_unlock;
 109	}
 110
 111	inst->queue_num = queue_num;
 112	inst->peer_pid = pid;
 113	inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
 114	inst->copy_range = 0xfffff;
 115	inst->copy_mode = NFQNL_COPY_NONE;
 116	spin_lock_init(&inst->lock);
 117	INIT_LIST_HEAD(&inst->queue_list);
 118
 119	if (!try_module_get(THIS_MODULE)) {
 120		err = -EAGAIN;
 121		goto out_free;
 122	}
 123
 124	h = instance_hashfn(queue_num);
 125	hlist_add_head_rcu(&inst->hlist, &instance_table[h]);
 126
 127	spin_unlock(&instances_lock);
 128
 129	return inst;
 130
 131out_free:
 132	kfree(inst);
 133out_unlock:
 134	spin_unlock(&instances_lock);
 135	return ERR_PTR(err);
 136}
 137
 138static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
 139			unsigned long data);
 140
 141static void
 142instance_destroy_rcu(struct rcu_head *head)
 143{
 144	struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
 145						   rcu);
 146
 147	nfqnl_flush(inst, NULL, 0);
 148	kfree(inst);
 149	module_put(THIS_MODULE);
 150}
 151
 152static void
 153__instance_destroy(struct nfqnl_instance *inst)
 154{
 155	hlist_del_rcu(&inst->hlist);
 156	call_rcu(&inst->rcu, instance_destroy_rcu);
 157}
 158
 159static void
 160instance_destroy(struct nfqnl_instance *inst)
 161{
 162	spin_lock(&instances_lock);
 163	__instance_destroy(inst);
 164	spin_unlock(&instances_lock);
 165}
 166
 167static inline void
 168__enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 169{
 170       list_add_tail(&entry->list, &queue->queue_list);
 171       queue->queue_total++;
 172}
 173
 174static void
 175__dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 176{
 177	list_del(&entry->list);
 178	queue->queue_total--;
 179}
 180
 181static struct nf_queue_entry *
 182find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
 183{
 184	struct nf_queue_entry *entry = NULL, *i;
 185
 186	spin_lock_bh(&queue->lock);
 187
 188	list_for_each_entry(i, &queue->queue_list, list) {
 189		if (i->id == id) {
 190			entry = i;
 191			break;
 192		}
 193	}
 194
 195	if (entry)
 196		__dequeue_entry(queue, entry);
 197
 198	spin_unlock_bh(&queue->lock);
 199
 200	return entry;
 201}
 202
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 203static void
 204nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
 205{
 206	struct nf_queue_entry *entry, *next;
 207
 208	spin_lock_bh(&queue->lock);
 209	list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
 210		if (!cmpfn || cmpfn(entry, data)) {
 211			list_del(&entry->list);
 212			queue->queue_total--;
 213			nf_reinject(entry, NF_DROP);
 214		}
 215	}
 216	spin_unlock_bh(&queue->lock);
 217}
 218
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 219static struct sk_buff *
 220nfqnl_build_packet_message(struct nfqnl_instance *queue,
 221			   struct nf_queue_entry *entry,
 222			   __be32 **packet_id_ptr)
 223{
 224	sk_buff_data_t old_tail;
 225	size_t size;
 226	size_t data_len = 0;
 
 227	struct sk_buff *skb;
 228	struct nlattr *nla;
 229	struct nfqnl_msg_packet_hdr *pmsg;
 230	struct nlmsghdr *nlh;
 231	struct nfgenmsg *nfmsg;
 232	struct sk_buff *entskb = entry->skb;
 233	struct net_device *indev;
 234	struct net_device *outdev;
 
 
 
 
 
 
 235
 236	size =    NLMSG_SPACE(sizeof(struct nfgenmsg))
 237		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
 238		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 239		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 240#ifdef CONFIG_BRIDGE_NETFILTER
 241		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 242		+ nla_total_size(sizeof(u_int32_t))	/* ifindex */
 243#endif
 244		+ nla_total_size(sizeof(u_int32_t))	/* mark */
 245		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
 246		+ nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
 
 
 
 
 
 
 247
 248	outdev = entry->outdev;
 
 
 
 
 249
 250	switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) {
 
 
 251	case NFQNL_COPY_META:
 252	case NFQNL_COPY_NONE:
 253		break;
 254
 255	case NFQNL_COPY_PACKET:
 256		if (entskb->ip_summed == CHECKSUM_PARTIAL &&
 
 257		    skb_checksum_help(entskb))
 258			return NULL;
 259
 260		data_len = ACCESS_ONCE(queue->copy_range);
 261		if (data_len == 0 || data_len > entskb->len)
 262			data_len = entskb->len;
 263
 264		size += nla_total_size(data_len);
 
 
 
 265		break;
 266	}
 267
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 268
 269	skb = alloc_skb(size, GFP_ATOMIC);
 270	if (!skb)
 
 271		goto nlmsg_failure;
 
 272
 273	old_tail = skb->tail;
 274	nlh = NLMSG_PUT(skb, 0, 0,
 275			NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
 276			sizeof(struct nfgenmsg));
 277	nfmsg = NLMSG_DATA(nlh);
 278	nfmsg->nfgen_family = entry->pf;
 
 
 
 
 279	nfmsg->version = NFNETLINK_V0;
 280	nfmsg->res_id = htons(queue->queue_num);
 281
 282	nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
 283	pmsg = nla_data(nla);
 284	pmsg->hw_protocol	= entskb->protocol;
 285	pmsg->hook		= entry->hook;
 286	*packet_id_ptr		= &pmsg->packet_id;
 287
 288	indev = entry->indev;
 289	if (indev) {
 290#ifndef CONFIG_BRIDGE_NETFILTER
 291		if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
 292			goto nla_put_failure;
 293#else
 294		if (entry->pf == PF_BRIDGE) {
 295			/* Case 1: indev is physical input device, we need to
 296			 * look for bridge group (when called from
 297			 * netfilter_bridge) */
 298			if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 299					 htonl(indev->ifindex)) ||
 300			/* this is the bridge group "brX" */
 301			/* rcu_read_lock()ed by __nf_queue */
 302			    nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 303					 htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
 304				goto nla_put_failure;
 305		} else {
 
 
 306			/* Case 2: indev is bridge group, we need to look for
 307			 * physical device (when called from ipv4) */
 308			if (nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 309					 htonl(indev->ifindex)))
 310				goto nla_put_failure;
 311			if (entskb->nf_bridge && entskb->nf_bridge->physindev &&
 
 
 312			    nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 313					 htonl(entskb->nf_bridge->physindev->ifindex)))
 314				goto nla_put_failure;
 315		}
 316#endif
 317	}
 318
 319	if (outdev) {
 320#ifndef CONFIG_BRIDGE_NETFILTER
 321		if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
 322			goto nla_put_failure;
 323#else
 324		if (entry->pf == PF_BRIDGE) {
 325			/* Case 1: outdev is physical output device, we need to
 326			 * look for bridge group (when called from
 327			 * netfilter_bridge) */
 328			if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 329					 htonl(outdev->ifindex)) ||
 330			/* this is the bridge group "brX" */
 331			/* rcu_read_lock()ed by __nf_queue */
 332			    nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 333					 htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
 334				goto nla_put_failure;
 335		} else {
 
 
 336			/* Case 2: outdev is bridge group, we need to look for
 337			 * physical output device (when called from ipv4) */
 338			if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 339					 htonl(outdev->ifindex)))
 340				goto nla_put_failure;
 341			if (entskb->nf_bridge && entskb->nf_bridge->physoutdev &&
 
 
 342			    nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 343					 htonl(entskb->nf_bridge->physoutdev->ifindex)))
 344				goto nla_put_failure;
 345		}
 346#endif
 347	}
 348
 349	if (entskb->mark &&
 350	    nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark)))
 351		goto nla_put_failure;
 352
 353	if (indev && entskb->dev &&
 354	    entskb->mac_header != entskb->network_header) {
 355		struct nfqnl_msg_packet_hw phw;
 356		int len = dev_parse_header(entskb, phw.hw_addr);
 
 
 
 357		if (len) {
 358			phw.hw_addrlen = htons(len);
 359			if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw))
 360				goto nla_put_failure;
 361		}
 362	}
 363
 364	if (entskb->tstamp.tv64) {
 
 
 
 365		struct nfqnl_msg_packet_timestamp ts;
 366		struct timeval tv = ktime_to_timeval(entskb->tstamp);
 367		ts.sec = cpu_to_be64(tv.tv_sec);
 368		ts.usec = cpu_to_be64(tv.tv_usec);
 
 369
 370		if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
 371			goto nla_put_failure;
 372	}
 373
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 374	if (data_len) {
 375		struct nlattr *nla;
 376		int sz = nla_attr_size(data_len);
 377
 378		if (skb_tailroom(skb) < nla_total_size(data_len)) {
 379			printk(KERN_WARNING "nf_queue: no tailroom!\n");
 380			goto nlmsg_failure;
 381		}
 382
 383		nla = (struct nlattr *)skb_put(skb, nla_total_size(data_len));
 384		nla->nla_type = NFQA_PAYLOAD;
 385		nla->nla_len = sz;
 386
 387		if (skb_copy_bits(entskb, 0, nla_data(nla), data_len))
 388			BUG();
 389	}
 390
 391	nlh->nlmsg_len = skb->tail - old_tail;
 
 
 392	return skb;
 393
 394nlmsg_failure:
 395nla_put_failure:
 396	if (skb)
 397		kfree_skb(skb);
 398	net_err_ratelimited("nf_queue: error creating packet message\n");
 
 
 
 399	return NULL;
 400}
 401
 
 
 
 
 
 
 
 
 
 
 
 
 402static int
 403nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 
 404{
 405	struct sk_buff *nskb;
 406	struct nfqnl_instance *queue;
 407	int err = -ENOBUFS;
 408	__be32 *packet_id_ptr;
 
 409
 410	/* rcu_read_lock()ed by nf_hook_slow() */
 411	queue = instance_lookup(queuenum);
 412	if (!queue) {
 413		err = -ESRCH;
 414		goto err_out;
 415	}
 416
 417	if (queue->copy_mode == NFQNL_COPY_NONE) {
 418		err = -EINVAL;
 419		goto err_out;
 420	}
 421
 422	nskb = nfqnl_build_packet_message(queue, entry, &packet_id_ptr);
 423	if (nskb == NULL) {
 424		err = -ENOMEM;
 425		goto err_out;
 426	}
 427	spin_lock_bh(&queue->lock);
 428
 429	if (!queue->peer_pid) {
 430		err = -EINVAL;
 431		goto err_out_free_nskb;
 432	}
 433	if (queue->queue_total >= queue->queue_maxlen) {
 434		queue->queue_dropped++;
 435		net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
 436				     queue->queue_total);
 
 
 
 
 
 437		goto err_out_free_nskb;
 438	}
 439	entry->id = ++queue->id_sequence;
 440	*packet_id_ptr = htonl(entry->id);
 441
 442	/* nfnetlink_unicast will either free the nskb or add it to a socket */
 443	err = nfnetlink_unicast(nskb, &init_net, queue->peer_pid, MSG_DONTWAIT);
 444	if (err < 0) {
 445		queue->queue_user_dropped++;
 
 
 
 
 
 446		goto err_out_unlock;
 447	}
 448
 449	__enqueue_entry(queue, entry);
 450
 451	spin_unlock_bh(&queue->lock);
 452	return 0;
 453
 454err_out_free_nskb:
 455	kfree_skb(nskb);
 456err_out_unlock:
 457	spin_unlock_bh(&queue->lock);
 
 
 458err_out:
 459	return err;
 460}
 461
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 462static int
 463nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e)
 464{
 465	struct sk_buff *nskb;
 466	int diff;
 467
 468	diff = data_len - e->skb->len;
 469	if (diff < 0) {
 470		if (pskb_trim(e->skb, data_len))
 471			return -ENOMEM;
 472	} else if (diff > 0) {
 473		if (data_len > 0xFFFF)
 474			return -EINVAL;
 475		if (diff > skb_tailroom(e->skb)) {
 476			nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
 477					       diff, GFP_ATOMIC);
 478			if (!nskb) {
 479				printk(KERN_WARNING "nf_queue: OOM "
 480				      "in mangle, dropping packet\n");
 481				return -ENOMEM;
 482			}
 483			kfree_skb(e->skb);
 484			e->skb = nskb;
 485		}
 486		skb_put(e->skb, diff);
 487	}
 488	if (!skb_make_writable(e->skb, data_len))
 489		return -ENOMEM;
 490	skb_copy_to_linear_data(e->skb, data, data_len);
 491	e->skb->ip_summed = CHECKSUM_NONE;
 492	return 0;
 493}
 494
 495static int
 496nfqnl_set_mode(struct nfqnl_instance *queue,
 497	       unsigned char mode, unsigned int range)
 498{
 499	int status = 0;
 500
 501	spin_lock_bh(&queue->lock);
 502	switch (mode) {
 503	case NFQNL_COPY_NONE:
 504	case NFQNL_COPY_META:
 505		queue->copy_mode = mode;
 506		queue->copy_range = 0;
 507		break;
 508
 509	case NFQNL_COPY_PACKET:
 510		queue->copy_mode = mode;
 511		/* we're using struct nlattr which has 16bit nla_len */
 512		if (range > 0xffff)
 513			queue->copy_range = 0xffff;
 514		else
 515			queue->copy_range = range;
 516		break;
 517
 518	default:
 519		status = -EINVAL;
 520
 521	}
 522	spin_unlock_bh(&queue->lock);
 523
 524	return status;
 525}
 526
 527static int
 528dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
 529{
 530	if (entry->indev)
 531		if (entry->indev->ifindex == ifindex)
 532			return 1;
 533	if (entry->outdev)
 534		if (entry->outdev->ifindex == ifindex)
 535			return 1;
 536#ifdef CONFIG_BRIDGE_NETFILTER
 537	if (entry->skb->nf_bridge) {
 538		if (entry->skb->nf_bridge->physindev &&
 539		    entry->skb->nf_bridge->physindev->ifindex == ifindex)
 
 540			return 1;
 541		if (entry->skb->nf_bridge->physoutdev &&
 542		    entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
 543			return 1;
 544	}
 545#endif
 546	return 0;
 547}
 548
 549/* drop all packets with either indev or outdev == ifindex from all queue
 550 * instances */
 551static void
 552nfqnl_dev_drop(int ifindex)
 553{
 554	int i;
 
 555
 556	rcu_read_lock();
 557
 558	for (i = 0; i < INSTANCE_BUCKETS; i++) {
 559		struct hlist_node *tmp;
 560		struct nfqnl_instance *inst;
 561		struct hlist_head *head = &instance_table[i];
 562
 563		hlist_for_each_entry_rcu(inst, tmp, head, hlist)
 564			nfqnl_flush(inst, dev_cmp, ifindex);
 565	}
 566
 567	rcu_read_unlock();
 568}
 569
 570#define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
 571
 572static int
 573nfqnl_rcv_dev_event(struct notifier_block *this,
 574		    unsigned long event, void *ptr)
 575{
 576	struct net_device *dev = ptr;
 577
 578	if (!net_eq(dev_net(dev), &init_net))
 579		return NOTIFY_DONE;
 580
 581	/* Drop any packets associated with the downed device */
 582	if (event == NETDEV_DOWN)
 583		nfqnl_dev_drop(dev->ifindex);
 584	return NOTIFY_DONE;
 585}
 586
 587static struct notifier_block nfqnl_dev_notifier = {
 588	.notifier_call	= nfqnl_rcv_dev_event,
 589};
 590
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 591static int
 592nfqnl_rcv_nl_event(struct notifier_block *this,
 593		   unsigned long event, void *ptr)
 594{
 595	struct netlink_notify *n = ptr;
 
 596
 597	if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
 598		int i;
 599
 600		/* destroy all instances for this pid */
 601		spin_lock(&instances_lock);
 602		for (i = 0; i < INSTANCE_BUCKETS; i++) {
 603			struct hlist_node *tmp, *t2;
 604			struct nfqnl_instance *inst;
 605			struct hlist_head *head = &instance_table[i];
 606
 607			hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) {
 608				if ((n->net == &init_net) &&
 609				    (n->pid == inst->peer_pid))
 610					__instance_destroy(inst);
 611			}
 612		}
 613		spin_unlock(&instances_lock);
 614	}
 615	return NOTIFY_DONE;
 616}
 617
 618static struct notifier_block nfqnl_rtnl_notifier = {
 619	.notifier_call	= nfqnl_rcv_nl_event,
 620};
 621
 
 
 
 
 
 622static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
 623	[NFQA_VERDICT_HDR]	= { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
 624	[NFQA_MARK]		= { .type = NLA_U32 },
 625	[NFQA_PAYLOAD]		= { .type = NLA_UNSPEC },
 
 
 
 626};
 627
 628static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
 629	[NFQA_VERDICT_HDR]	= { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
 630	[NFQA_MARK]		= { .type = NLA_U32 },
 631};
 632
 633static struct nfqnl_instance *verdict_instance_lookup(u16 queue_num, int nlpid)
 
 634{
 635	struct nfqnl_instance *queue;
 636
 637	queue = instance_lookup(queue_num);
 638	if (!queue)
 639		return ERR_PTR(-ENODEV);
 640
 641	if (queue->peer_pid != nlpid)
 642		return ERR_PTR(-EPERM);
 643
 644	return queue;
 645}
 646
 647static struct nfqnl_msg_verdict_hdr*
 648verdicthdr_get(const struct nlattr * const nfqa[])
 649{
 650	struct nfqnl_msg_verdict_hdr *vhdr;
 651	unsigned int verdict;
 652
 653	if (!nfqa[NFQA_VERDICT_HDR])
 654		return NULL;
 655
 656	vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
 657	verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
 658	if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
 659		return NULL;
 660	return vhdr;
 661}
 662
 663static int nfq_id_after(unsigned int id, unsigned int max)
 664{
 665	return (int)(id - max) > 0;
 666}
 667
 668static int
 669nfqnl_recv_verdict_batch(struct sock *ctnl, struct sk_buff *skb,
 670		   const struct nlmsghdr *nlh,
 671		   const struct nlattr * const nfqa[])
 
 672{
 673	struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 674	struct nf_queue_entry *entry, *tmp;
 675	unsigned int verdict, maxid;
 676	struct nfqnl_msg_verdict_hdr *vhdr;
 677	struct nfqnl_instance *queue;
 678	LIST_HEAD(batch_list);
 679	u16 queue_num = ntohs(nfmsg->res_id);
 
 680
 681	queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).pid);
 
 682	if (IS_ERR(queue))
 683		return PTR_ERR(queue);
 684
 685	vhdr = verdicthdr_get(nfqa);
 686	if (!vhdr)
 687		return -EINVAL;
 688
 689	verdict = ntohl(vhdr->verdict);
 690	maxid = ntohl(vhdr->id);
 691
 692	spin_lock_bh(&queue->lock);
 693
 694	list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
 695		if (nfq_id_after(entry->id, maxid))
 696			break;
 697		__dequeue_entry(queue, entry);
 698		list_add_tail(&entry->list, &batch_list);
 699	}
 700
 701	spin_unlock_bh(&queue->lock);
 702
 703	if (list_empty(&batch_list))
 704		return -ENOENT;
 705
 706	list_for_each_entry_safe(entry, tmp, &batch_list, list) {
 707		if (nfqa[NFQA_MARK])
 708			entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
 709		nf_reinject(entry, verdict);
 
 710	}
 711	return 0;
 712}
 713
 714static int
 715nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
 716		   const struct nlmsghdr *nlh,
 717		   const struct nlattr * const nfqa[])
 
 718{
 719	struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 720	u_int16_t queue_num = ntohs(nfmsg->res_id);
 721
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 722	struct nfqnl_msg_verdict_hdr *vhdr;
 723	struct nfqnl_instance *queue;
 724	unsigned int verdict;
 725	struct nf_queue_entry *entry;
 
 
 
 
 
 726
 727	queue = instance_lookup(queue_num);
 728	if (!queue)
 729
 730	queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).pid);
 731	if (IS_ERR(queue))
 732		return PTR_ERR(queue);
 733
 734	vhdr = verdicthdr_get(nfqa);
 735	if (!vhdr)
 736		return -EINVAL;
 737
 738	verdict = ntohl(vhdr->verdict);
 739
 740	entry = find_dequeue_entry(queue, ntohl(vhdr->id));
 741	if (entry == NULL)
 742		return -ENOENT;
 743
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 744	if (nfqa[NFQA_PAYLOAD]) {
 
 
 
 745		if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
 746				 nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0)
 747			verdict = NF_DROP;
 
 
 
 748	}
 749
 750	if (nfqa[NFQA_MARK])
 751		entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
 752
 753	nf_reinject(entry, verdict);
 754	return 0;
 755}
 756
 757static int
 758nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
 759		  const struct nlmsghdr *nlh,
 760		  const struct nlattr * const nfqa[])
 761{
 762	return -ENOTSUPP;
 763}
 764
 765static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
 766	[NFQA_CFG_CMD]		= { .len = sizeof(struct nfqnl_msg_config_cmd) },
 767	[NFQA_CFG_PARAMS]	= { .len = sizeof(struct nfqnl_msg_config_params) },
 
 
 
 768};
 769
 770static const struct nf_queue_handler nfqh = {
 771	.name 	= "nf_queue",
 772	.outfn	= &nfqnl_enqueue_packet,
 773};
 774
 775static int
 776nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
 777		  const struct nlmsghdr *nlh,
 778		  const struct nlattr * const nfqa[])
 779{
 780	struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 781	u_int16_t queue_num = ntohs(nfmsg->res_id);
 782	struct nfqnl_instance *queue;
 783	struct nfqnl_msg_config_cmd *cmd = NULL;
 
 
 784	int ret = 0;
 785
 786	if (nfqa[NFQA_CFG_CMD]) {
 787		cmd = nla_data(nfqa[NFQA_CFG_CMD]);
 788
 789		/* Commands without queue context - might sleep */
 790		switch (cmd->command) {
 791		case NFQNL_CFG_CMD_PF_BIND:
 792			return nf_register_queue_handler(ntohs(cmd->pf),
 793							 &nfqh);
 794		case NFQNL_CFG_CMD_PF_UNBIND:
 795			return nf_unregister_queue_handler(ntohs(cmd->pf),
 796							   &nfqh);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 797		}
 798	}
 799
 800	rcu_read_lock();
 801	queue = instance_lookup(queue_num);
 802	if (queue && queue->peer_pid != NETLINK_CB(skb).pid) {
 803		ret = -EPERM;
 804		goto err_out_unlock;
 805	}
 806
 807	if (cmd != NULL) {
 808		switch (cmd->command) {
 809		case NFQNL_CFG_CMD_BIND:
 810			if (queue) {
 811				ret = -EBUSY;
 812				goto err_out_unlock;
 813			}
 814			queue = instance_create(queue_num, NETLINK_CB(skb).pid);
 
 815			if (IS_ERR(queue)) {
 816				ret = PTR_ERR(queue);
 817				goto err_out_unlock;
 818			}
 819			break;
 820		case NFQNL_CFG_CMD_UNBIND:
 821			if (!queue) {
 822				ret = -ENODEV;
 823				goto err_out_unlock;
 824			}
 825			instance_destroy(queue);
 826			break;
 827		case NFQNL_CFG_CMD_PF_BIND:
 828		case NFQNL_CFG_CMD_PF_UNBIND:
 829			break;
 830		default:
 831			ret = -ENOTSUPP;
 832			break;
 833		}
 834	}
 835
 
 
 
 
 
 836	if (nfqa[NFQA_CFG_PARAMS]) {
 837		struct nfqnl_msg_config_params *params;
 
 838
 839		if (!queue) {
 840			ret = -ENODEV;
 841			goto err_out_unlock;
 842		}
 843		params = nla_data(nfqa[NFQA_CFG_PARAMS]);
 844		nfqnl_set_mode(queue, params->copy_mode,
 845				ntohl(params->copy_range));
 846	}
 847
 848	if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
 849		__be32 *queue_maxlen;
 850
 851		if (!queue) {
 852			ret = -ENODEV;
 853			goto err_out_unlock;
 854		}
 855		queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
 856		spin_lock_bh(&queue->lock);
 857		queue->queue_maxlen = ntohl(*queue_maxlen);
 858		spin_unlock_bh(&queue->lock);
 859	}
 860
 
 
 
 
 
 
 
 861err_out_unlock:
 862	rcu_read_unlock();
 863	return ret;
 864}
 865
 866static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
 867	[NFQNL_MSG_PACKET]	= { .call_rcu = nfqnl_recv_unsupp,
 868				    .attr_count = NFQA_MAX, },
 869	[NFQNL_MSG_VERDICT]	= { .call_rcu = nfqnl_recv_verdict,
 870				    .attr_count = NFQA_MAX,
 871				    .policy = nfqa_verdict_policy },
 872	[NFQNL_MSG_CONFIG]	= { .call = nfqnl_recv_config,
 873				    .attr_count = NFQA_CFG_MAX,
 874				    .policy = nfqa_cfg_policy },
 875	[NFQNL_MSG_VERDICT_BATCH]={ .call_rcu = nfqnl_recv_verdict_batch,
 876				    .attr_count = NFQA_MAX,
 877				    .policy = nfqa_verdict_batch_policy },
 878};
 879
 880static const struct nfnetlink_subsystem nfqnl_subsys = {
 881	.name		= "nf_queue",
 882	.subsys_id	= NFNL_SUBSYS_QUEUE,
 883	.cb_count	= NFQNL_MSG_MAX,
 884	.cb		= nfqnl_cb,
 885};
 886
 887#ifdef CONFIG_PROC_FS
 888struct iter_state {
 
 889	unsigned int bucket;
 890};
 891
 892static struct hlist_node *get_first(struct seq_file *seq)
 893{
 894	struct iter_state *st = seq->private;
 
 
 895
 896	if (!st)
 897		return NULL;
 898
 
 
 899	for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
 900		if (!hlist_empty(&instance_table[st->bucket]))
 901			return instance_table[st->bucket].first;
 902	}
 903	return NULL;
 904}
 905
 906static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
 907{
 908	struct iter_state *st = seq->private;
 
 909
 910	h = h->next;
 911	while (!h) {
 
 
 912		if (++st->bucket >= INSTANCE_BUCKETS)
 913			return NULL;
 914
 915		h = instance_table[st->bucket].first;
 
 916	}
 917	return h;
 918}
 919
 920static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
 921{
 922	struct hlist_node *head;
 923	head = get_first(seq);
 924
 925	if (head)
 926		while (pos && (head = get_next(seq, head)))
 927			pos--;
 928	return pos ? NULL : head;
 929}
 930
 931static void *seq_start(struct seq_file *seq, loff_t *pos)
 932	__acquires(instances_lock)
 933{
 934	spin_lock(&instances_lock);
 935	return get_idx(seq, *pos);
 936}
 937
 938static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
 939{
 940	(*pos)++;
 941	return get_next(s, v);
 942}
 943
 944static void seq_stop(struct seq_file *s, void *v)
 945	__releases(instances_lock)
 946{
 947	spin_unlock(&instances_lock);
 948}
 949
 950static int seq_show(struct seq_file *s, void *v)
 951{
 952	const struct nfqnl_instance *inst = v;
 953
 954	return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
 955			  inst->queue_num,
 956			  inst->peer_pid, inst->queue_total,
 957			  inst->copy_mode, inst->copy_range,
 958			  inst->queue_dropped, inst->queue_user_dropped,
 959			  inst->id_sequence, 1);
 
 960}
 961
 962static const struct seq_operations nfqnl_seq_ops = {
 963	.start	= seq_start,
 964	.next	= seq_next,
 965	.stop	= seq_stop,
 966	.show	= seq_show,
 967};
 
 968
 969static int nfqnl_open(struct inode *inode, struct file *file)
 970{
 971	return seq_open_private(file, &nfqnl_seq_ops,
 972			sizeof(struct iter_state));
 
 
 
 
 
 
 
 
 
 
 
 
 
 973}
 974
 975static const struct file_operations nfqnl_file_ops = {
 976	.owner	 = THIS_MODULE,
 977	.open	 = nfqnl_open,
 978	.read	 = seq_read,
 979	.llseek	 = seq_lseek,
 980	.release = seq_release_private,
 981};
 982
 983#endif /* PROC_FS */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 984
 985static int __init nfnetlink_queue_init(void)
 986{
 987	int i, status = -ENOMEM;
 988
 989	for (i = 0; i < INSTANCE_BUCKETS; i++)
 990		INIT_HLIST_HEAD(&instance_table[i]);
 
 
 
 991
 992	netlink_register_notifier(&nfqnl_rtnl_notifier);
 993	status = nfnetlink_subsys_register(&nfqnl_subsys);
 994	if (status < 0) {
 995		printk(KERN_ERR "nf_queue: failed to create netlink socket\n");
 996		goto cleanup_netlink_notifier;
 997	}
 998
 999#ifdef CONFIG_PROC_FS
1000	if (!proc_create("nfnetlink_queue", 0440,
1001			 proc_net_netfilter, &nfqnl_file_ops))
1002		goto cleanup_subsys;
1003#endif
1004
1005	register_netdevice_notifier(&nfqnl_dev_notifier);
1006	return status;
1007
1008#ifdef CONFIG_PROC_FS
1009cleanup_subsys:
1010	nfnetlink_subsys_unregister(&nfqnl_subsys);
1011#endif
1012cleanup_netlink_notifier:
1013	netlink_unregister_notifier(&nfqnl_rtnl_notifier);
 
 
1014	return status;
1015}
1016
1017static void __exit nfnetlink_queue_fini(void)
1018{
1019	nf_unregister_queue_handlers(&nfqh);
1020	unregister_netdevice_notifier(&nfqnl_dev_notifier);
1021#ifdef CONFIG_PROC_FS
1022	remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
1023#endif
1024	nfnetlink_subsys_unregister(&nfqnl_subsys);
1025	netlink_unregister_notifier(&nfqnl_rtnl_notifier);
 
1026
1027	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1028}
1029
1030MODULE_DESCRIPTION("netfilter packet queue handler");
1031MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1032MODULE_LICENSE("GPL");
1033MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1034
1035module_init(nfnetlink_queue_init);
1036module_exit(nfnetlink_queue_fini);