[net-next-2.6.git] / net / bridge / netfilter / ebt_ulog.c

/*
 * netfilter module for userspace bridged Ethernet frames logging daemons
 *
 *	Authors:
 *	Bart De Schuymer <bdschuym@pandora.be>
 *	Harald Welte <laforge@netfilter.org>
 *
 *  November, 2004
 *
 * Based on ipt_ULOG.c, which is
 * (C) 2000-2002 by Harald Welte <laforge@netfilter.org>
 *
 * This module accepts two parameters: 
 * 
 * nlbufsiz:
 *   The parameter specifies how big the buffer for each netlink multicast
 * group is. e.g. If you say nlbufsiz=8192, up to eight kb of packets will
 * get accumulated in the kernel until they are sent to userspace. It is
 * NOT possible to allocate more than 128kB, and it is strongly discouraged,
 * because atomically allocating 128kB inside the network rx softirq is not
 * reliable. Please also keep in mind that this buffer size is allocated for
 * each nlgroup you are using, so the total kernel memory usage increases
 * by that factor.
 *
 * flushtimeout:
 *   Specify, after how many hundredths of a second the queue should be
 *   flushed even if it is not full yet.
 *
 */

#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/socket.h>
#include <linux/skbuff.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/netlink.h>
#include <linux/netdevice.h>
#include <linux/module.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_ulog.h>
#include <net/sock.h>
#include "../br_private.h"

#define PRINTR(format, args...) do { if (net_ratelimit()) \
                                printk(format , ## args); } while (0)

static unsigned int nlbufsiz = NLMSG_GOODSIZE;
module_param(nlbufsiz, uint, 0600);
MODULE_PARM_DESC(nlbufsiz, "netlink buffer size (number of bytes) "
                           "(defaults to 4096)");

static unsigned int flushtimeout = 10;
module_param(flushtimeout, uint, 0600);
MODULE_PARM_DESC(flushtimeout, "buffer flush timeout (hundredths ofa second) "
                               "(defaults to 10)");

typedef struct {
	unsigned int qlen;		/* number of nlmsgs' in the skb */
	struct nlmsghdr *lastnlh;	/* netlink header of last msg in skb */
	struct sk_buff *skb;		/* the pre-allocated skb */
	struct timer_list timer;	/* the timer function */
	spinlock_t lock;		/* the per-queue lock */
} ebt_ulog_buff_t;

static ebt_ulog_buff_t ulog_buffers[EBT_ULOG_MAXNLGROUPS];
static struct sock *ebtulognl;

/* send one ulog_buff_t to userspace */
static void ulog_send(unsigned int nlgroup)
{
	ebt_ulog_buff_t *ub = &ulog_buffers[nlgroup];

	if (timer_pending(&ub->timer))
		del_timer(&ub->timer);

	if (!ub->skb)
		return;

	/* last nlmsg needs NLMSG_DONE */
	if (ub->qlen > 1)
		ub->lastnlh->nlmsg_type = NLMSG_DONE;

	NETLINK_CB(ub->skb).dst_group = nlgroup + 1;
	netlink_broadcast(ebtulognl, ub->skb, 0, nlgroup + 1, GFP_ATOMIC);

	ub->qlen = 0;
	ub->skb = NULL;
}

/* timer function to flush queue in flushtimeout time */
static void ulog_timer(unsigned long data)
{
	spin_lock_bh(&ulog_buffers[data].lock);
	if (ulog_buffers[data].skb)
		ulog_send(data);
	spin_unlock_bh(&ulog_buffers[data].lock);
}

static struct sk_buff *ulog_alloc_skb(unsigned int size)
{
	struct sk_buff *skb;
	unsigned int n;

	n = max(size, nlbufsiz);
	skb = alloc_skb(n, GFP_ATOMIC);
	if (!skb) {
		PRINTR(KERN_ERR "ebt_ulog: can't alloc whole buffer "
		       "of size %ub!\n", n);
		if (n > size) {
			/* try to allocate only as much as we need for
			 * current packet */
			skb = alloc_skb(size, GFP_ATOMIC);
			if (!skb)
				PRINTR(KERN_ERR "ebt_ulog: can't even allocate "
				       "buffer of size %ub\n", size);
		}
	}

	return skb;
}

static void ebt_ulog_packet(unsigned int hooknr, const struct sk_buff *skb,
   const struct net_device *in, const struct net_device *out,
   const struct ebt_ulog_info *uloginfo, const char *prefix)
{
	ebt_ulog_packet_msg_t *pm;
	size_t size, copy_len;
	struct nlmsghdr *nlh;
	unsigned int group = uloginfo->nlgroup;
	ebt_ulog_buff_t *ub = &ulog_buffers[group];
	spinlock_t *lock = &ub->lock;

	if ((uloginfo->cprange == 0) ||
	    (uloginfo->cprange > skb->len + ETH_HLEN))
		copy_len = skb->len + ETH_HLEN;
	else
		copy_len = uloginfo->cprange;

	size = NLMSG_SPACE(sizeof(*pm) + copy_len);
	if (size > nlbufsiz) {
		PRINTR("ebt_ulog: Size %Zd needed, but nlbufsiz=%d\n",
		       size, nlbufsiz);
		return;
	}

	spin_lock_bh(lock);

	if (!ub->skb) {
		if (!(ub->skb = ulog_alloc_skb(size)))
			goto alloc_failure;
	} else if (size > skb_tailroom(ub->skb)) {
		ulog_send(group);

		if (!(ub->skb = ulog_alloc_skb(size)))
			goto alloc_failure;
	}

	nlh = NLMSG_PUT(ub->skb, 0, ub->qlen, 0,
	                size - NLMSG_ALIGN(sizeof(*nlh)));
	ub->qlen++;

	pm = NLMSG_DATA(nlh);

	/* Fill in the ulog data */
	pm->version = EBT_ULOG_VERSION;
	do_gettimeofday(&pm->stamp);
	if (ub->qlen == 1)
		skb_set_timestamp(ub->skb, &pm->stamp);
	pm->data_len = copy_len;
	pm->mark = skb->nfmark;
	pm->hook = hooknr;
	if (uloginfo->prefix != NULL)
		strcpy(pm->prefix, uloginfo->prefix);
	else
		*(pm->prefix) = '\0';

	if (in) {
		strcpy(pm->physindev, in->name);
		/* If in isn't a bridge, then physindev==indev */
		if (in->br_port)
			strcpy(pm->indev, in->br_port->br->dev->name);
		else
			strcpy(pm->indev, in->name);
	} else
		pm->indev[0] = pm->physindev[0] = '\0';

	if (out) {
		/* If out exists, then out is a bridge port */
		strcpy(pm->physoutdev, out->name);
		strcpy(pm->outdev, out->br_port->br->dev->name);
	} else
		pm->outdev[0] = pm->physoutdev[0] = '\0';

	if (skb_copy_bits(skb, -ETH_HLEN, pm->data, copy_len) < 0)
		BUG();

	if (ub->qlen > 1)
		ub->lastnlh->nlmsg_flags |= NLM_F_MULTI;

	ub->lastnlh = nlh;

	if (ub->qlen >= uloginfo->qthreshold)
		ulog_send(group);
	else if (!timer_pending(&ub->timer)) {
		ub->timer.expires = jiffies + flushtimeout * HZ / 100;
		add_timer(&ub->timer);
	}

unlock:
	spin_unlock_bh(lock);

	return;

nlmsg_failure:
	printk(KERN_CRIT "ebt_ulog: error during NLMSG_PUT. This should "
	       "not happen, please report to author.\n");
	goto unlock;
alloc_failure:
	goto unlock;
}

/* this function is registered with the netfilter core */
static void ebt_log_packet(unsigned int pf, unsigned int hooknum,
   const struct sk_buff *skb, const struct net_device *in,
   const struct net_device *out, const struct nf_loginfo *li,
   const char *prefix)
{
	struct ebt_ulog_info loginfo;

	if (!li || li->type != NF_LOG_TYPE_ULOG) {
		loginfo.nlgroup = EBT_ULOG_DEFAULT_NLGROUP;
		loginfo.cprange = 0;
		loginfo.qthreshold = EBT_ULOG_DEFAULT_QTHRESHOLD;
		loginfo.prefix[0] = '\0';
	} else {
		loginfo.nlgroup = li->u.ulog.group;
		loginfo.cprange = li->u.ulog.copy_len;
		loginfo.qthreshold = li->u.ulog.qthreshold;
		strlcpy(loginfo.prefix, prefix, sizeof(loginfo.prefix));
	}

	ebt_ulog_packet(hooknum, skb, in, out, &loginfo, prefix);
}

static void ebt_ulog(const struct sk_buff *skb, unsigned int hooknr,
   const struct net_device *in, const struct net_device *out,
   const void *data, unsigned int datalen)
{
	struct ebt_ulog_info *uloginfo = (struct ebt_ulog_info *)data;

	ebt_ulog_packet(hooknr, skb, in, out, uloginfo, NULL);
}


static int ebt_ulog_check(const char *tablename, unsigned int hookmask,
   const struct ebt_entry *e, void *data, unsigned int datalen)
{
	struct ebt_ulog_info *uloginfo = (struct ebt_ulog_info *)data;

	if (datalen != EBT_ALIGN(sizeof(struct ebt_ulog_info)) ||
	    uloginfo->nlgroup > 31)
		return -EINVAL;

	uloginfo->prefix[EBT_ULOG_PREFIX_LEN - 1] = '\0';

	if (uloginfo->qthreshold > EBT_ULOG_MAX_QLEN)
		uloginfo->qthreshold = EBT_ULOG_MAX_QLEN;

	return 0;
}

static struct ebt_watcher ulog = {
	.name		= EBT_ULOG_WATCHER,
	.watcher	= ebt_ulog,
	.check		= ebt_ulog_check,
	.me		= THIS_MODULE,
};

static struct nf_logger ebt_ulog_logger = {
	.name		= EBT_ULOG_WATCHER,
	.logfn		= &ebt_log_packet,
	.me		= THIS_MODULE,
};

static int __init ebt_ulog_init(void)
{
	int i, ret = 0;

	if (nlbufsiz >= 128*1024) {
		printk(KERN_NOTICE "ebt_ulog: Netlink buffer has to be <= 128kB,"
		       " please try a smaller nlbufsiz parameter.\n");
		return -EINVAL;
	}

	/* initialize ulog_buffers */
	for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) {
		init_timer(&ulog_buffers[i].timer);
		ulog_buffers[i].timer.function = ulog_timer;
		ulog_buffers[i].timer.data = i;
		spin_lock_init(&ulog_buffers[i].lock);
	}

	ebtulognl = netlink_kernel_create(NETLINK_NFLOG, EBT_ULOG_MAXNLGROUPS,
	                                  NULL, THIS_MODULE);
	if (!ebtulognl)
		ret = -ENOMEM;
	else if ((ret = ebt_register_watcher(&ulog)))
		sock_release(ebtulognl->sk_socket);

	if (nf_log_register(PF_BRIDGE, &ebt_ulog_logger) < 0) {
		printk(KERN_WARNING "ebt_ulog: not logging via ulog "
		       "since somebody else already registered for PF_BRIDGE\n");
		/* we cannot make module load fail here, since otherwise
		 * ebtables userspace would abort */
	}

	return ret;
}

static void __exit ebt_ulog_fini(void)
{
	ebt_ulog_buff_t *ub;
	int i;

	nf_log_unregister_logger(&ebt_ulog_logger);
	ebt_unregister_watcher(&ulog);
	for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) {
		ub = &ulog_buffers[i];
		if (timer_pending(&ub->timer))
			del_timer(&ub->timer);
		spin_lock_bh(&ub->lock);
		if (ub->skb) {
			kfree_skb(ub->skb);
			ub->skb = NULL;
		}
		spin_unlock_bh(&ub->lock);
	}
	sock_release(ebtulognl->sk_socket);
}

module_init(ebt_ulog_init);
module_exit(ebt_ulog_fini);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Bart De Schuymer <bdschuym@pandora.be>");
MODULE_DESCRIPTION("ebtables userspace logging module for bridged Ethernet"
                   " frames");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* netfilter module for userspace bridged Ethernet frames logging daemons
	3	*
	4	* Authors:
	5	* Bart De Schuymer <bdschuym@pandora.be>
d5228a4f	6	* Harald Welte <laforge@netfilter.org>
1da177e4 LT	7	*
	8	* November, 2004
	9	*
	10	* Based on ipt_ULOG.c, which is
	11	* (C) 2000-2002 by Harald Welte <laforge@netfilter.org>
	12	*
	13	* This module accepts two parameters:
	14	*
	15	* nlbufsiz:
	16	* The parameter specifies how big the buffer for each netlink multicast
	17	* group is. e.g. If you say nlbufsiz=8192, up to eight kb of packets will
	18	* get accumulated in the kernel until they are sent to userspace. It is
	19	* NOT possible to allocate more than 128kB, and it is strongly discouraged,
	20	* because atomically allocating 128kB inside the network rx softirq is not
	21	* reliable. Please also keep in mind that this buffer size is allocated for
	22	* each nlgroup you are using, so the total kernel memory usage increases
	23	* by that factor.
	24	*
	25	* flushtimeout:
	26	* Specify, after how many hundredths of a second the queue should be
	27	* flushed even if it is not full yet.
	28	*
	29	*/
	30
	31	#include <linux/module.h>
1da177e4 LT	32	#include <linux/spinlock.h>
	33	#include <linux/socket.h>
	34	#include <linux/skbuff.h>
	35	#include <linux/kernel.h>
	36	#include <linux/timer.h>
	37	#include <linux/netlink.h>
	38	#include <linux/netdevice.h>
	39	#include <linux/module.h>
	40	#include <linux/netfilter_bridge/ebtables.h>
	41	#include <linux/netfilter_bridge/ebt_ulog.h>
	42	#include <net/sock.h>
	43	#include "../br_private.h"
	44
	45	#define PRINTR(format, args...) do { if (net_ratelimit()) \
	46	printk(format , ## args); } while (0)
	47
c2db2924	48	static unsigned int nlbufsiz = NLMSG_GOODSIZE;
1da177e4 LT	49	module_param(nlbufsiz, uint, 0600);
	50	MODULE_PARM_DESC(nlbufsiz, "netlink buffer size (number of bytes) "
	51	"(defaults to 4096)");
	52
	53	static unsigned int flushtimeout = 10;
	54	module_param(flushtimeout, uint, 0600);
	55	MODULE_PARM_DESC(flushtimeout, "buffer flush timeout (hundredths ofa second) "
	56	"(defaults to 10)");
	57
	58	typedef struct {
	59	unsigned int qlen; /* number of nlmsgs' in the skb */
	60	struct nlmsghdr lastnlh; / netlink header of last msg in skb */
	61	struct sk_buff skb; / the pre-allocated skb */
	62	struct timer_list timer; /* the timer function */
	63	spinlock_t lock; /* the per-queue lock */
	64	} ebt_ulog_buff_t;
	65
	66	static ebt_ulog_buff_t ulog_buffers[EBT_ULOG_MAXNLGROUPS];
	67	static struct sock *ebtulognl;
	68
	69	/* send one ulog_buff_t to userspace */
	70	static void ulog_send(unsigned int nlgroup)
	71	{
	72	ebt_ulog_buff_t *ub = &ulog_buffers[nlgroup];
	73
	74	if (timer_pending(&ub->timer))
	75	del_timer(&ub->timer);
	76
dcb7cd97 MH	77	if (!ub->skb)
	78	return;
	79
1da177e4 LT	80	/* last nlmsg needs NLMSG_DONE */
	81	if (ub->qlen > 1)
	82	ub->lastnlh->nlmsg_type = NLMSG_DONE;
	83
ac6d439d PM	84	NETLINK_CB(ub->skb).dst_group = nlgroup + 1;
ac6d439d PM	85	netlink_broadcast(ebtulognl, ub->skb, 0, nlgroup + 1, GFP_ATOMIC);
1da177e4 LT	86
	87	ub->qlen = 0;
	88	ub->skb = NULL;
	89	}
	90
	91	/* timer function to flush queue in flushtimeout time */
	92	static void ulog_timer(unsigned long data)
	93	{
	94	spin_lock_bh(&ulog_buffers[data].lock);
	95	if (ulog_buffers[data].skb)
	96	ulog_send(data);
	97	spin_unlock_bh(&ulog_buffers[data].lock);
	98	}
	99
	100	static struct sk_buff *ulog_alloc_skb(unsigned int size)
	101	{
	102	struct sk_buff *skb;
ad2ad0f9	103	unsigned int n;
1da177e4	104
ad2ad0f9 PM	105	n = max(size, nlbufsiz);
ad2ad0f9 PM	106	skb = alloc_skb(n, GFP_ATOMIC);
1da177e4 LT	107	if (!skb) {
1da177e4 LT	108	PRINTR(KERN_ERR "ebt_ulog: can't alloc whole buffer "
ad2ad0f9 PM	109	"of size %ub!\n", n);
ad2ad0f9 PM	110	if (n > size) {
1da177e4 LT	111	/* try to allocate only as much as we need for
	112	* current packet */
	113	skb = alloc_skb(size, GFP_ATOMIC);
	114	if (!skb)
	115	PRINTR(KERN_ERR "ebt_ulog: can't even allocate "
	116	"buffer of size %ub\n", size);
	117	}
	118	}
	119
	120	return skb;
	121	}
	122
d5228a4f	123	static void ebt_ulog_packet(unsigned int hooknr, const struct sk_buff *skb,
1da177e4	124	const struct net_device in, const struct net_device out,
d5228a4f	125	const struct ebt_ulog_info uloginfo, const char prefix)
1da177e4 LT	126	{
	127	ebt_ulog_packet_msg_t *pm;
	128	size_t size, copy_len;
	129	struct nlmsghdr *nlh;
1da177e4 LT	130	unsigned int group = uloginfo->nlgroup;
	131	ebt_ulog_buff_t *ub = &ulog_buffers[group];
	132	spinlock_t *lock = &ub->lock;
	133
	134	if ((uloginfo->cprange == 0) \|\|
	135	(uloginfo->cprange > skb->len + ETH_HLEN))
	136	copy_len = skb->len + ETH_HLEN;
	137	else
	138	copy_len = uloginfo->cprange;
	139
	140	size = NLMSG_SPACE(sizeof(*pm) + copy_len);
	141	if (size > nlbufsiz) {
	142	PRINTR("ebt_ulog: Size %Zd needed, but nlbufsiz=%d\n",
	143	size, nlbufsiz);
	144	return;
	145	}
	146
	147	spin_lock_bh(lock);
	148
	149	if (!ub->skb) {
	150	if (!(ub->skb = ulog_alloc_skb(size)))
	151	goto alloc_failure;
	152	} else if (size > skb_tailroom(ub->skb)) {
	153	ulog_send(group);
	154
	155	if (!(ub->skb = ulog_alloc_skb(size)))
	156	goto alloc_failure;
	157	}
	158
	159	nlh = NLMSG_PUT(ub->skb, 0, ub->qlen, 0,
	160	size - NLMSG_ALIGN(sizeof(*nlh)));
	161	ub->qlen++;
	162
	163	pm = NLMSG_DATA(nlh);
	164
	165	/* Fill in the ulog data */
	166	pm->version = EBT_ULOG_VERSION;
	167	do_gettimeofday(&pm->stamp);
	168	if (ub->qlen == 1)
a61bbcf2	169	skb_set_timestamp(ub->skb, &pm->stamp);
1da177e4 LT	170	pm->data_len = copy_len;
	171	pm->mark = skb->nfmark;
	172	pm->hook = hooknr;
	173	if (uloginfo->prefix != NULL)
	174	strcpy(pm->prefix, uloginfo->prefix);
	175	else
	176	*(pm->prefix) = '\0';
	177
	178	if (in) {
	179	strcpy(pm->physindev, in->name);
	180	/* If in isn't a bridge, then physindev==indev */
	181	if (in->br_port)
	182	strcpy(pm->indev, in->br_port->br->dev->name);
	183	else
	184	strcpy(pm->indev, in->name);
	185	} else
	186	pm->indev[0] = pm->physindev[0] = '\0';
	187
	188	if (out) {
	189	/* If out exists, then out is a bridge port */
	190	strcpy(pm->physoutdev, out->name);
	191	strcpy(pm->outdev, out->br_port->br->dev->name);
	192	} else
	193	pm->outdev[0] = pm->physoutdev[0] = '\0';
	194
	195	if (skb_copy_bits(skb, -ETH_HLEN, pm->data, copy_len) < 0)
	196	BUG();
	197
	198	if (ub->qlen > 1)
	199	ub->lastnlh->nlmsg_flags \|= NLM_F_MULTI;
	200
	201	ub->lastnlh = nlh;
	202
	203	if (ub->qlen >= uloginfo->qthreshold)
	204	ulog_send(group);
	205	else if (!timer_pending(&ub->timer)) {
	206	ub->timer.expires = jiffies + flushtimeout * HZ / 100;
	207	add_timer(&ub->timer);
	208	}
	209
	210	unlock:
	211	spin_unlock_bh(lock);
	212
	213	return;
	214
	215	nlmsg_failure:
	216	printk(KERN_CRIT "ebt_ulog: error during NLMSG_PUT. This should "
	217	"not happen, please report to author.\n");
	218	goto unlock;
	219	alloc_failure:
	220	goto unlock;
	221	}
	222
d5228a4f BDS	223	/* this function is registered with the netfilter core */
	224	static void ebt_log_packet(unsigned int pf, unsigned int hooknum,
	225	const struct sk_buff skb, const struct net_device in,
	226	const struct net_device out, const struct nf_loginfo li,
	227	const char *prefix)
	228	{
	229	struct ebt_ulog_info loginfo;
	230
	231	if (!li \|\| li->type != NF_LOG_TYPE_ULOG) {
	232	loginfo.nlgroup = EBT_ULOG_DEFAULT_NLGROUP;
	233	loginfo.cprange = 0;
	234	loginfo.qthreshold = EBT_ULOG_DEFAULT_QTHRESHOLD;
	235	loginfo.prefix[0] = '\0';
	236	} else {
	237	loginfo.nlgroup = li->u.ulog.group;
	238	loginfo.cprange = li->u.ulog.copy_len;
	239	loginfo.qthreshold = li->u.ulog.qthreshold;
	240	strlcpy(loginfo.prefix, prefix, sizeof(loginfo.prefix));
	241	}
	242
	243	ebt_ulog_packet(hooknum, skb, in, out, &loginfo, prefix);
	244	}
	245
	246	static void ebt_ulog(const struct sk_buff *skb, unsigned int hooknr,
	247	const struct net_device in, const struct net_device out,
	248	const void *data, unsigned int datalen)
	249	{
	250	struct ebt_ulog_info uloginfo = (struct ebt_ulog_info )data;
	251
	252	ebt_ulog_packet(hooknr, skb, in, out, uloginfo, NULL);
	253	}
	254
	255
1da177e4 LT	256	static int ebt_ulog_check(const char *tablename, unsigned int hookmask,
	257	const struct ebt_entry e, void data, unsigned int datalen)
	258	{
	259	struct ebt_ulog_info uloginfo = (struct ebt_ulog_info )data;
	260
	261	if (datalen != EBT_ALIGN(sizeof(struct ebt_ulog_info)) \|\|
	262	uloginfo->nlgroup > 31)
	263	return -EINVAL;
	264
	265	uloginfo->prefix[EBT_ULOG_PREFIX_LEN - 1] = '\0';
	266
	267	if (uloginfo->qthreshold > EBT_ULOG_MAX_QLEN)
	268	uloginfo->qthreshold = EBT_ULOG_MAX_QLEN;
	269
	270	return 0;
	271	}
	272
	273	static struct ebt_watcher ulog = {
	274	.name = EBT_ULOG_WATCHER,
	275	.watcher = ebt_ulog,
	276	.check = ebt_ulog_check,
	277	.me = THIS_MODULE,
	278	};
	279
d5228a4f BDS	280	static struct nf_logger ebt_ulog_logger = {
	281	.name = EBT_ULOG_WATCHER,
	282	.logfn = &ebt_log_packet,
	283	.me = THIS_MODULE,
	284	};
	285
65b4b4e8	286	static int __init ebt_ulog_init(void)
1da177e4 LT	287	{
	288	int i, ret = 0;
	289
	290	if (nlbufsiz >= 128*1024) {
	291	printk(KERN_NOTICE "ebt_ulog: Netlink buffer has to be <= 128kB,"
	292	" please try a smaller nlbufsiz parameter.\n");
	293	return -EINVAL;
	294	}
	295
	296	/* initialize ulog_buffers */
	297	for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) {
	298	init_timer(&ulog_buffers[i].timer);
	299	ulog_buffers[i].timer.function = ulog_timer;
	300	ulog_buffers[i].timer.data = i;
	301	spin_lock_init(&ulog_buffers[i].lock);
	302	}
	303
06628607 PM	304	ebtulognl = netlink_kernel_create(NETLINK_NFLOG, EBT_ULOG_MAXNLGROUPS,
06628607 PM	305	NULL, THIS_MODULE);
1da177e4 LT	306	if (!ebtulognl)
	307	ret = -ENOMEM;
	308	else if ((ret = ebt_register_watcher(&ulog)))
	309	sock_release(ebtulognl->sk_socket);
	310
d5228a4f BDS	311	if (nf_log_register(PF_BRIDGE, &ebt_ulog_logger) < 0) {
	312	printk(KERN_WARNING "ebt_ulog: not logging via ulog "
	313	"since somebody else already registered for PF_BRIDGE\n");
	314	/* we cannot make module load fail here, since otherwise
	315	* ebtables userspace would abort */
	316	}
	317
1da177e4 LT	318	return ret;
	319	}
	320
65b4b4e8	321	static void __exit ebt_ulog_fini(void)
1da177e4 LT	322	{
	323	ebt_ulog_buff_t *ub;
	324	int i;
	325
d5228a4f	326	nf_log_unregister_logger(&ebt_ulog_logger);
1da177e4 LT	327	ebt_unregister_watcher(&ulog);
	328	for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) {
	329	ub = &ulog_buffers[i];
	330	if (timer_pending(&ub->timer))
	331	del_timer(&ub->timer);
	332	spin_lock_bh(&ub->lock);
	333	if (ub->skb) {
	334	kfree_skb(ub->skb);
	335	ub->skb = NULL;
	336	}
	337	spin_unlock_bh(&ub->lock);
	338	}
	339	sock_release(ebtulognl->sk_socket);
	340	}
	341
65b4b4e8 AM	342	module_init(ebt_ulog_init);
65b4b4e8 AM	343	module_exit(ebt_ulog_fini);
1da177e4 LT	344	MODULE_LICENSE("GPL");
	345	MODULE_AUTHOR("Bart De Schuymer <bdschuym@pandora.be>");
	346	MODULE_DESCRIPTION("ebtables userspace logging module for bridged Ethernet"
	347	" frames");