[linux-block.git] / net / netfilter / nf_log.c

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/skbuff.h>
#include <linux/netfilter.h>
#include <linux/seq_file.h>
#include <net/protocol.h>
#include <net/netfilter/nf_log.h>

#include "nf_internals.h"

/* Internal logging interface, which relies on the real
   LOG target modules */

#define NF_LOG_PREFIXLEN		128
#define NFLOGGER_NAME_LEN		64

static struct nf_logger __rcu *loggers[NFPROTO_NUMPROTO][NF_LOG_TYPE_MAX] __read_mostly;
static DEFINE_MUTEX(nf_log_mutex);

#define nft_log_dereference(logger) \
	rcu_dereference_protected(logger, lockdep_is_held(&nf_log_mutex))

static struct nf_logger *__find_logger(int pf, const char *str_logger)
{
	struct nf_logger *log;
	int i;

	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
		if (loggers[pf][i] == NULL)
			continue;

		log = nft_log_dereference(loggers[pf][i]);
		if (!strncasecmp(str_logger, log->name, strlen(log->name)))
			return log;
	}

	return NULL;
}

void nf_log_set(struct net *net, u_int8_t pf, const struct nf_logger *logger)
{
	const struct nf_logger *log;

	if (pf == NFPROTO_UNSPEC)
		return;

	mutex_lock(&nf_log_mutex);
	log = nft_log_dereference(net->nf.nf_loggers[pf]);
	if (log == NULL)
		rcu_assign_pointer(net->nf.nf_loggers[pf], logger);

	mutex_unlock(&nf_log_mutex);
}
EXPORT_SYMBOL(nf_log_set);

void nf_log_unset(struct net *net, const struct nf_logger *logger)
{
	int i;
	const struct nf_logger *log;

	mutex_lock(&nf_log_mutex);
	for (i = 0; i < NFPROTO_NUMPROTO; i++) {
		log = nft_log_dereference(net->nf.nf_loggers[i]);
		if (log == logger)
			RCU_INIT_POINTER(net->nf.nf_loggers[i], NULL);
	}
	mutex_unlock(&nf_log_mutex);
	synchronize_rcu();
}
EXPORT_SYMBOL(nf_log_unset);

/* return EEXIST if the same logger is registered, 0 on success. */
int nf_log_register(u_int8_t pf, struct nf_logger *logger)
{
	int i;
	int ret = 0;

	if (pf >= ARRAY_SIZE(init_net.nf.nf_loggers))
		return -EINVAL;

	mutex_lock(&nf_log_mutex);

	if (pf == NFPROTO_UNSPEC) {
		for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
			if (rcu_access_pointer(loggers[i][logger->type])) {
				ret = -EEXIST;
				goto unlock;
			}
		}
		for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
			rcu_assign_pointer(loggers[i][logger->type], logger);
	} else {
		if (rcu_access_pointer(loggers[pf][logger->type])) {
			ret = -EEXIST;
			goto unlock;
		}
		rcu_assign_pointer(loggers[pf][logger->type], logger);
	}

unlock:
	mutex_unlock(&nf_log_mutex);
	return ret;
}
EXPORT_SYMBOL(nf_log_register);

void nf_log_unregister(struct nf_logger *logger)
{
	const struct nf_logger *log;
	int i;

	mutex_lock(&nf_log_mutex);
	for (i = 0; i < NFPROTO_NUMPROTO; i++) {
		log = nft_log_dereference(loggers[i][logger->type]);
		if (log == logger)
			RCU_INIT_POINTER(loggers[i][logger->type], NULL);
	}
	mutex_unlock(&nf_log_mutex);
	synchronize_rcu();
}
EXPORT_SYMBOL(nf_log_unregister);

int nf_log_bind_pf(struct net *net, u_int8_t pf,
		   const struct nf_logger *logger)
{
	if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
		return -EINVAL;
	mutex_lock(&nf_log_mutex);
	if (__find_logger(pf, logger->name) == NULL) {
		mutex_unlock(&nf_log_mutex);
		return -ENOENT;
	}
	rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
	mutex_unlock(&nf_log_mutex);
	return 0;
}
EXPORT_SYMBOL(nf_log_bind_pf);

void nf_log_unbind_pf(struct net *net, u_int8_t pf)
{
	if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
		return;
	mutex_lock(&nf_log_mutex);
	RCU_INIT_POINTER(net->nf.nf_loggers[pf], NULL);
	mutex_unlock(&nf_log_mutex);
}
EXPORT_SYMBOL(nf_log_unbind_pf);

void nf_logger_request_module(int pf, enum nf_log_type type)
{
	if (loggers[pf][type] == NULL)
		request_module("nf-logger-%u-%u", pf, type);
}
EXPORT_SYMBOL_GPL(nf_logger_request_module);

int nf_logger_find_get(int pf, enum nf_log_type type)
{
	struct nf_logger *logger;
	int ret = -ENOENT;

	if (pf == NFPROTO_INET) {
		ret = nf_logger_find_get(NFPROTO_IPV4, type);
		if (ret < 0)
			return ret;

		ret = nf_logger_find_get(NFPROTO_IPV6, type);
		if (ret < 0) {
			nf_logger_put(NFPROTO_IPV4, type);
			return ret;
		}

		return 0;
	}

	if (rcu_access_pointer(loggers[pf][type]) == NULL)
		request_module("nf-logger-%u-%u", pf, type);

	rcu_read_lock();
	logger = rcu_dereference(loggers[pf][type]);
	if (logger == NULL)
		goto out;

	if (try_module_get(logger->me))
		ret = 0;
out:
	rcu_read_unlock();
	return ret;
}
EXPORT_SYMBOL_GPL(nf_logger_find_get);

void nf_logger_put(int pf, enum nf_log_type type)
{
	struct nf_logger *logger;

	if (pf == NFPROTO_INET) {
		nf_logger_put(NFPROTO_IPV4, type);
		nf_logger_put(NFPROTO_IPV6, type);
		return;
	}

	BUG_ON(loggers[pf][type] == NULL);

	rcu_read_lock();
	logger = rcu_dereference(loggers[pf][type]);
	module_put(logger->me);
	rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(nf_logger_put);

void nf_log_packet(struct net *net,
		   u_int8_t pf,
		   unsigned int hooknum,
		   const struct sk_buff *skb,
		   const struct net_device *in,
		   const struct net_device *out,
		   const struct nf_loginfo *loginfo,
		   const char *fmt, ...)
{
	va_list args;
	char prefix[NF_LOG_PREFIXLEN];
	const struct nf_logger *logger;

	rcu_read_lock();
	if (loginfo != NULL)
		logger = rcu_dereference(loggers[pf][loginfo->type]);
	else
		logger = rcu_dereference(net->nf.nf_loggers[pf]);

	if (logger) {
		va_start(args, fmt);
		vsnprintf(prefix, sizeof(prefix), fmt, args);
		va_end(args);
		logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
	}
	rcu_read_unlock();
}
EXPORT_SYMBOL(nf_log_packet);

void nf_log_trace(struct net *net,
		  u_int8_t pf,
		  unsigned int hooknum,
		  const struct sk_buff *skb,
		  const struct net_device *in,
		  const struct net_device *out,
		  const struct nf_loginfo *loginfo, const char *fmt, ...)
{
	va_list args;
	char prefix[NF_LOG_PREFIXLEN];
	const struct nf_logger *logger;

	rcu_read_lock();
	logger = rcu_dereference(net->nf.nf_loggers[pf]);
	if (logger) {
		va_start(args, fmt);
		vsnprintf(prefix, sizeof(prefix), fmt, args);
		va_end(args);
		logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
	}
	rcu_read_unlock();
}
EXPORT_SYMBOL(nf_log_trace);

#define S_SIZE (1024 - (sizeof(unsigned int) + 1))

struct nf_log_buf {
	unsigned int	count;
	char		buf[S_SIZE + 1];
};
static struct nf_log_buf emergency, *emergency_ptr = &emergency;

__printf(2, 3) int nf_log_buf_add(struct nf_log_buf *m, const char *f, ...)
{
	va_list args;
	int len;

	if (likely(m->count < S_SIZE)) {
		va_start(args, f);
		len = vsnprintf(m->buf + m->count, S_SIZE - m->count, f, args);
		va_end(args);
		if (likely(m->count + len < S_SIZE)) {
			m->count += len;
			return 0;
		}
	}
	m->count = S_SIZE;
	printk_once(KERN_ERR KBUILD_MODNAME " please increase S_SIZE\n");
	return -1;
}
EXPORT_SYMBOL_GPL(nf_log_buf_add);

struct nf_log_buf *nf_log_buf_open(void)
{
	struct nf_log_buf *m = kmalloc(sizeof(*m), GFP_ATOMIC);

	if (unlikely(!m)) {
		local_bh_disable();
		do {
			m = xchg(&emergency_ptr, NULL);
		} while (!m);
	}
	m->count = 0;
	return m;
}
EXPORT_SYMBOL_GPL(nf_log_buf_open);

void nf_log_buf_close(struct nf_log_buf *m)
{
	m->buf[m->count] = 0;
	printk("%s\n", m->buf);

	if (likely(m != &emergency))
		kfree(m);
	else {
		emergency_ptr = m;
		local_bh_enable();
	}
}
EXPORT_SYMBOL_GPL(nf_log_buf_close);

#ifdef CONFIG_PROC_FS
static void *seq_start(struct seq_file *seq, loff_t *pos)
{
	struct net *net = seq_file_net(seq);

	mutex_lock(&nf_log_mutex);

	if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
		return NULL;

	return pos;
}

static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
{
	struct net *net = seq_file_net(s);

	(*pos)++;

	if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
		return NULL;

	return pos;
}

static void seq_stop(struct seq_file *s, void *v)
{
	mutex_unlock(&nf_log_mutex);
}

static int seq_show(struct seq_file *s, void *v)
{
	loff_t *pos = v;
	const struct nf_logger *logger;
	int i;
	struct net *net = seq_file_net(s);

	logger = nft_log_dereference(net->nf.nf_loggers[*pos]);

	if (!logger)
		seq_printf(s, "%2lld NONE (", *pos);
	else
		seq_printf(s, "%2lld %s (", *pos, logger->name);

	if (seq_has_overflowed(s))
		return -ENOSPC;

	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
		if (loggers[*pos][i] == NULL)
			continue;

		logger = nft_log_dereference(loggers[*pos][i]);
		seq_printf(s, "%s", logger->name);
		if (i == 0 && loggers[*pos][i + 1] != NULL)
			seq_printf(s, ",");

		if (seq_has_overflowed(s))
			return -ENOSPC;
	}

	seq_printf(s, ")\n");

	if (seq_has_overflowed(s))
		return -ENOSPC;
	return 0;
}

static const struct seq_operations nflog_seq_ops = {
	.start	= seq_start,
	.next	= seq_next,
	.stop	= seq_stop,
	.show	= seq_show,
};

static int nflog_open(struct inode *inode, struct file *file)
{
	return seq_open_net(inode, file, &nflog_seq_ops,
			    sizeof(struct seq_net_private));
}

static const struct file_operations nflog_file_ops = {
	.owner	 = THIS_MODULE,
	.open	 = nflog_open,
	.read	 = seq_read,
	.llseek	 = seq_lseek,
	.release = seq_release_net,
};


#endif /* PROC_FS */

#ifdef CONFIG_SYSCTL
static char nf_log_sysctl_fnames[NFPROTO_NUMPROTO-NFPROTO_UNSPEC][3];
static struct ctl_table nf_log_sysctl_table[NFPROTO_NUMPROTO+1];

static int nf_log_proc_dostring(struct ctl_table *table, int write,
			 void __user *buffer, size_t *lenp, loff_t *ppos)
{
	const struct nf_logger *logger;
	char buf[NFLOGGER_NAME_LEN];
	int r = 0;
	int tindex = (unsigned long)table->extra1;
	struct net *net = current->nsproxy->net_ns;

	if (write) {
		struct ctl_table tmp = *table;

		tmp.data = buf;
		r = proc_dostring(&tmp, write, buffer, lenp, ppos);
		if (r)
			return r;

		if (!strcmp(buf, "NONE")) {
			nf_log_unbind_pf(net, tindex);
			return 0;
		}
		mutex_lock(&nf_log_mutex);
		logger = __find_logger(tindex, buf);
		if (logger == NULL) {
			mutex_unlock(&nf_log_mutex);
			return -ENOENT;
		}
		rcu_assign_pointer(net->nf.nf_loggers[tindex], logger);
		mutex_unlock(&nf_log_mutex);
	} else {
		mutex_lock(&nf_log_mutex);
		logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
		if (!logger)
			table->data = "NONE";
		else
			table->data = logger->name;
		r = proc_dostring(table, write, buffer, lenp, ppos);
		mutex_unlock(&nf_log_mutex);
	}

	return r;
}

static int netfilter_log_sysctl_init(struct net *net)
{
	int i;
	struct ctl_table *table;

	table = nf_log_sysctl_table;
	if (!net_eq(net, &init_net)) {
		table = kmemdup(nf_log_sysctl_table,
				 sizeof(nf_log_sysctl_table),
				 GFP_KERNEL);
		if (!table)
			goto err_alloc;
	} else {
		for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
			snprintf(nf_log_sysctl_fnames[i],
				 3, "%d", i);
			nf_log_sysctl_table[i].procname	=
				nf_log_sysctl_fnames[i];
			nf_log_sysctl_table[i].data = NULL;
			nf_log_sysctl_table[i].maxlen = NFLOGGER_NAME_LEN;
			nf_log_sysctl_table[i].mode = 0644;
			nf_log_sysctl_table[i].proc_handler =
				nf_log_proc_dostring;
			nf_log_sysctl_table[i].extra1 =
				(void *)(unsigned long) i;
		}
	}

	net->nf.nf_log_dir_header = register_net_sysctl(net,
						"net/netfilter/nf_log",
						table);
	if (!net->nf.nf_log_dir_header)
		goto err_reg;

	return 0;

err_reg:
	if (!net_eq(net, &init_net))
		kfree(table);
err_alloc:
	return -ENOMEM;
}

static void netfilter_log_sysctl_exit(struct net *net)
{
	struct ctl_table *table;

	table = net->nf.nf_log_dir_header->ctl_table_arg;
	unregister_net_sysctl_table(net->nf.nf_log_dir_header);
	if (!net_eq(net, &init_net))
		kfree(table);
}
#else
static int netfilter_log_sysctl_init(struct net *net)
{
	return 0;
}

static void netfilter_log_sysctl_exit(struct net *net)
{
}
#endif /* CONFIG_SYSCTL */

static int __net_init nf_log_net_init(struct net *net)
{
	int ret = -ENOMEM;

#ifdef CONFIG_PROC_FS
	if (!proc_create("nf_log", S_IRUGO,
			 net->nf.proc_netfilter, &nflog_file_ops))
		return ret;
#endif
	ret = netfilter_log_sysctl_init(net);
	if (ret < 0)
		goto out_sysctl;

	return 0;

out_sysctl:
#ifdef CONFIG_PROC_FS
	remove_proc_entry("nf_log", net->nf.proc_netfilter);
#endif
	return ret;
}

static void __net_exit nf_log_net_exit(struct net *net)
{
	netfilter_log_sysctl_exit(net);
#ifdef CONFIG_PROC_FS
	remove_proc_entry("nf_log", net->nf.proc_netfilter);
#endif
}

static struct pernet_operations nf_log_net_ops = {
	.init = nf_log_net_init,
	.exit = nf_log_net_exit,
};

int __init netfilter_log_init(void)
{
	return register_pernet_subsys(&nf_log_net_ops);
}
Commit	Line	Data
f6ebe77f HW	1	#include <linux/kernel.h>
	2	#include <linux/init.h>
	3	#include <linux/module.h>
	4	#include <linux/proc_fs.h>
	5	#include <linux/skbuff.h>
	6	#include <linux/netfilter.h>
bbd86b9f	7	#include <linux/seq_file.h>
f6ebe77f	8	#include <net/protocol.h>
f01ffbd6	9	#include <net/netfilter/nf_log.h>
f6ebe77f HW	10
	11	#include "nf_internals.h"
	12
a5d29264	13	/* Internal logging interface, which relies on the real
f6ebe77f HW	14	LOG target modules */
	15
	16	#define NF_LOG_PREFIXLEN 128
17625274	17	#define NFLOGGER_NAME_LEN 64
f6ebe77f	18
5962815a	19	static struct nf_logger __rcu *loggers[NFPROTO_NUMPROTO][NF_LOG_TYPE_MAX] __read_mostly;
9b73534d	20	static DEFINE_MUTEX(nf_log_mutex);
f6ebe77f	21
0c26ed1c ML	22	#define nft_log_dereference(logger) \
	23	rcu_dereference_protected(logger, lockdep_is_held(&nf_log_mutex))
	24
ca735b3a	25	static struct nf_logger __find_logger(int pf, const char str_logger)
f6ebe77f	26	{
5962815a PNA	27	struct nf_logger *log;
	28	int i;
	29
	30	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
	31	if (loggers[pf][i] == NULL)
	32	continue;
f6ebe77f	33
0c26ed1c	34	log = nft_log_dereference(loggers[pf][i]);
18082746	35	if (!strncasecmp(str_logger, log->name, strlen(log->name)))
5962815a	36	return log;
ca735b3a	37	}
d72367b6	38
ca735b3a	39	return NULL;
601e68e1	40	}
f6ebe77f	41
30e0c6a6 G	42	void nf_log_set(struct net net, u_int8_t pf, const struct nf_logger logger)
	43	{
	44	const struct nf_logger *log;
	45
30e0c6a6 G	46	if (pf == NFPROTO_UNSPEC)
	47	return;
	48
	49	mutex_lock(&nf_log_mutex);
0c26ed1c	50	log = nft_log_dereference(net->nf.nf_loggers[pf]);
30e0c6a6 G	51	if (log == NULL)
	52	rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
	53
	54	mutex_unlock(&nf_log_mutex);
	55	}
	56	EXPORT_SYMBOL(nf_log_set);
	57
	58	void nf_log_unset(struct net net, const struct nf_logger logger)
	59	{
	60	int i;
	61	const struct nf_logger *log;
	62
30e0c6a6 G	63	mutex_lock(&nf_log_mutex);
30e0c6a6 G	64	for (i = 0; i < NFPROTO_NUMPROTO; i++) {
0c26ed1c	65	log = nft_log_dereference(net->nf.nf_loggers[i]);
30e0c6a6 G	66	if (log == logger)
	67	RCU_INIT_POINTER(net->nf.nf_loggers[i], NULL);
	68	}
	69	mutex_unlock(&nf_log_mutex);
	70	synchronize_rcu();
	71	}
	72	EXPORT_SYMBOL(nf_log_unset);
	73
d93cf068	74	/* return EEXIST if the same logger is registered, 0 on success. */
ca735b3a	75	int nf_log_register(u_int8_t pf, struct nf_logger *logger)
f6ebe77f	76	{
b6f0a365	77	int i;
8ac2bde2	78	int ret = 0;
ca735b3a	79
30e0c6a6	80	if (pf >= ARRAY_SIZE(init_net.nf.nf_loggers))
ca735b3a EL	81	return -EINVAL;
ca735b3a EL	82
9b73534d	83	mutex_lock(&nf_log_mutex);
ca735b3a EL	84
ca735b3a EL	85	if (pf == NFPROTO_UNSPEC) {
8ac2bde2 ML	86	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
	87	if (rcu_access_pointer(loggers[i][logger->type])) {
	88	ret = -EEXIST;
	89	goto unlock;
	90	}
	91	}
ca735b3a	92	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
5962815a	93	rcu_assign_pointer(loggers[i][logger->type], logger);
ca735b3a	94	} else {
8ac2bde2 ML	95	if (rcu_access_pointer(loggers[pf][logger->type])) {
	96	ret = -EEXIST;
	97	goto unlock;
	98	}
5962815a	99	rcu_assign_pointer(loggers[pf][logger->type], logger);
ca735b3a EL	100	}
ca735b3a EL	101
8ac2bde2	102	unlock:
9b73534d	103	mutex_unlock(&nf_log_mutex);
8ac2bde2	104	return ret;
f6ebe77f	105	}
ca735b3a	106	EXPORT_SYMBOL(nf_log_register);
f6ebe77f	107
ca735b3a	108	void nf_log_unregister(struct nf_logger *logger)
f6ebe77f	109	{
205ee117	110	const struct nf_logger *log;
f6ebe77f HW	111	int i;
f6ebe77f HW	112
9b73534d	113	mutex_lock(&nf_log_mutex);
205ee117 FW	114	for (i = 0; i < NFPROTO_NUMPROTO; i++) {
	115	log = nft_log_dereference(loggers[i][logger->type]);
	116	if (log == logger)
	117	RCU_INIT_POINTER(loggers[i][logger->type], NULL);
	118	}
9b73534d	119	mutex_unlock(&nf_log_mutex);
ad5001cc	120	synchronize_rcu();
f6ebe77f	121	}
e92ad99c	122	EXPORT_SYMBOL(nf_log_unregister);
f6ebe77f	123
30e0c6a6 G	124	int nf_log_bind_pf(struct net *net, u_int8_t pf,
30e0c6a6 G	125	const struct nf_logger *logger)
ca735b3a	126	{
30e0c6a6	127	if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
9ef0298a	128	return -EINVAL;
ca735b3a EL	129	mutex_lock(&nf_log_mutex);
	130	if (__find_logger(pf, logger->name) == NULL) {
	131	mutex_unlock(&nf_log_mutex);
	132	return -ENOENT;
	133	}
30e0c6a6	134	rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
ca735b3a EL	135	mutex_unlock(&nf_log_mutex);
	136	return 0;
	137	}
	138	EXPORT_SYMBOL(nf_log_bind_pf);
	139
30e0c6a6	140	void nf_log_unbind_pf(struct net *net, u_int8_t pf)
ca735b3a	141	{
30e0c6a6	142	if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
9ef0298a	143	return;
ca735b3a	144	mutex_lock(&nf_log_mutex);
30e0c6a6	145	RCU_INIT_POINTER(net->nf.nf_loggers[pf], NULL);
ca735b3a EL	146	mutex_unlock(&nf_log_mutex);
	147	}
	148	EXPORT_SYMBOL(nf_log_unbind_pf);
	149
960649d1 PNA	150	void nf_logger_request_module(int pf, enum nf_log_type type)
	151	{
	152	if (loggers[pf][type] == NULL)
	153	request_module("nf-logger-%u-%u", pf, type);
	154	}
	155	EXPORT_SYMBOL_GPL(nf_logger_request_module);
	156
fab4085f PNA	157	int nf_logger_find_get(int pf, enum nf_log_type type)
	158	{
	159	struct nf_logger *logger;
	160	int ret = -ENOENT;
	161
f3bb5333 LZ	162	if (pf == NFPROTO_INET) {
	163	ret = nf_logger_find_get(NFPROTO_IPV4, type);
	164	if (ret < 0)
	165	return ret;
	166
	167	ret = nf_logger_find_get(NFPROTO_IPV6, type);
	168	if (ret < 0) {
	169	nf_logger_put(NFPROTO_IPV4, type);
	170	return ret;
	171	}
	172
	173	return 0;
	174	}
	175
c5a589cc	176	if (rcu_access_pointer(loggers[pf][type]) == NULL)
fab4085f PNA	177	request_module("nf-logger-%u-%u", pf, type);
	178
	179	rcu_read_lock();
	180	logger = rcu_dereference(loggers[pf][type]);
	181	if (logger == NULL)
	182	goto out;
	183
7e53e7f8	184	if (try_module_get(logger->me))
fab4085f PNA	185	ret = 0;
	186	out:
	187	rcu_read_unlock();
	188	return ret;
	189	}
	190	EXPORT_SYMBOL_GPL(nf_logger_find_get);
	191
	192	void nf_logger_put(int pf, enum nf_log_type type)
	193	{
	194	struct nf_logger *logger;
	195
f3bb5333 LZ	196	if (pf == NFPROTO_INET) {
	197	nf_logger_put(NFPROTO_IPV4, type);
	198	nf_logger_put(NFPROTO_IPV6, type);
	199	return;
	200	}
	201
fab4085f PNA	202	BUG_ON(loggers[pf][type] == NULL);
	203
	204	rcu_read_lock();
	205	logger = rcu_dereference(loggers[pf][type]);
	206	module_put(logger->me);
	207	rcu_read_unlock();
	208	}
	209	EXPORT_SYMBOL_GPL(nf_logger_put);
	210
30e0c6a6 G	211	void nf_log_packet(struct net *net,
30e0c6a6 G	212	u_int8_t pf,
f6ebe77f HW	213	unsigned int hooknum,
	214	const struct sk_buff *skb,
	215	const struct net_device *in,
	216	const struct net_device *out,
7b2f9631	217	const struct nf_loginfo *loginfo,
f6ebe77f HW	218	const char *fmt, ...)
	219	{
	220	va_list args;
	221	char prefix[NF_LOG_PREFIXLEN];
7b2f9631	222	const struct nf_logger *logger;
601e68e1	223
f6ebe77f	224	rcu_read_lock();
fab4085f PNA	225	if (loginfo != NULL)
	226	logger = rcu_dereference(loggers[pf][loginfo->type]);
	227	else
	228	logger = rcu_dereference(net->nf.nf_loggers[pf]);
	229
f6ebe77f HW	230	if (logger) {
	231	va_start(args, fmt);
	232	vsnprintf(prefix, sizeof(prefix), fmt, args);
	233	va_end(args);
8cdb46da	234	logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
f6ebe77f HW	235	}
	236	rcu_read_unlock();
	237	}
	238	EXPORT_SYMBOL(nf_log_packet);
	239
4017a7ee PNA	240	void nf_log_trace(struct net *net,
	241	u_int8_t pf,
	242	unsigned int hooknum,
	243	const struct sk_buff *skb,
	244	const struct net_device *in,
	245	const struct net_device *out,
	246	const struct nf_loginfo loginfo, const char fmt, ...)
	247	{
	248	va_list args;
	249	char prefix[NF_LOG_PREFIXLEN];
	250	const struct nf_logger *logger;
	251
	252	rcu_read_lock();
	253	logger = rcu_dereference(net->nf.nf_loggers[pf]);
	254	if (logger) {
	255	va_start(args, fmt);
	256	vsnprintf(prefix, sizeof(prefix), fmt, args);
	257	va_end(args);
	258	logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
	259	}
	260	rcu_read_unlock();
	261	}
	262	EXPORT_SYMBOL(nf_log_trace);
	263
27fd8d90 PNA	264	#define S_SIZE (1024 - (sizeof(unsigned int) + 1))
	265
	266	struct nf_log_buf {
	267	unsigned int count;
	268	char buf[S_SIZE + 1];
	269	};
	270	static struct nf_log_buf emergency, *emergency_ptr = &emergency;
	271
	272	__printf(2, 3) int nf_log_buf_add(struct nf_log_buf m, const char f, ...)
	273	{
	274	va_list args;
	275	int len;
	276
	277	if (likely(m->count < S_SIZE)) {
	278	va_start(args, f);
	279	len = vsnprintf(m->buf + m->count, S_SIZE - m->count, f, args);
	280	va_end(args);
	281	if (likely(m->count + len < S_SIZE)) {
	282	m->count += len;
	283	return 0;
	284	}
	285	}
	286	m->count = S_SIZE;
	287	printk_once(KERN_ERR KBUILD_MODNAME " please increase S_SIZE\n");
	288	return -1;
	289	}
	290	EXPORT_SYMBOL_GPL(nf_log_buf_add);
	291
	292	struct nf_log_buf *nf_log_buf_open(void)
	293	{
	294	struct nf_log_buf m = kmalloc(sizeof(m), GFP_ATOMIC);
	295
	296	if (unlikely(!m)) {
	297	local_bh_disable();
	298	do {
	299	m = xchg(&emergency_ptr, NULL);
	300	} while (!m);
	301	}
	302	m->count = 0;
	303	return m;
	304	}
	305	EXPORT_SYMBOL_GPL(nf_log_buf_open);
	306
	307	void nf_log_buf_close(struct nf_log_buf *m)
	308	{
	309	m->buf[m->count] = 0;
	310	printk("%s\n", m->buf);
	311
	312	if (likely(m != &emergency))
	313	kfree(m);
	314	else {
	315	emergency_ptr = m;
	316	local_bh_enable();
	317	}
	318	}
	319	EXPORT_SYMBOL_GPL(nf_log_buf_close);
	320
f6ebe77f HW	321	#ifdef CONFIG_PROC_FS
	322	static void seq_start(struct seq_file seq, loff_t *pos)
	323	{
30e0c6a6 G	324	struct net *net = seq_file_net(seq);
30e0c6a6 G	325
6440fe05	326	mutex_lock(&nf_log_mutex);
f6ebe77f	327
30e0c6a6	328	if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
f6ebe77f HW	329	return NULL;
	330
	331	return pos;
	332	}
	333
	334	static void seq_next(struct seq_file s, void v, loff_t pos)
	335	{
30e0c6a6 G	336	struct net *net = seq_file_net(s);
30e0c6a6 G	337
f6ebe77f HW	338	(*pos)++;
f6ebe77f HW	339
30e0c6a6	340	if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
f6ebe77f HW	341	return NULL;
	342
	343	return pos;
	344	}
	345
	346	static void seq_stop(struct seq_file s, void v)
	347	{
6440fe05	348	mutex_unlock(&nf_log_mutex);
f6ebe77f HW	349	}
	350
	351	static int seq_show(struct seq_file s, void v)
	352	{
	353	loff_t *pos = v;
	354	const struct nf_logger *logger;
e71456ae	355	int i;
30e0c6a6	356	struct net *net = seq_file_net(s);
f6ebe77f	357
0c26ed1c	358	logger = nft_log_dereference(net->nf.nf_loggers[*pos]);
f6ebe77f HW	359
f6ebe77f HW	360	if (!logger)
e71456ae	361	seq_printf(s, "%2lld NONE (", *pos);
c7a913cd	362	else
e71456ae	363	seq_printf(s, "%2lld %s (", *pos, logger->name);
c7a913cd	364
e71456ae SRRH	365	if (seq_has_overflowed(s))
e71456ae SRRH	366	return -ENOSPC;
c7a913cd	367
5962815a PNA	368	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
	369	if (loggers[*pos][i] == NULL)
	370	continue;
	371
0c26ed1c	372	logger = nft_log_dereference(loggers[*pos][i]);
e71456ae SRRH	373	seq_printf(s, "%s", logger->name);
	374	if (i == 0 && loggers[*pos][i + 1] != NULL)
	375	seq_printf(s, ",");
	376
	377	if (seq_has_overflowed(s))
	378	return -ENOSPC;
c7a913cd	379	}
601e68e1	380
e71456ae SRRH	381	seq_printf(s, ")\n");
	382
	383	if (seq_has_overflowed(s))
	384	return -ENOSPC;
	385	return 0;
f6ebe77f HW	386	}
f6ebe77f HW	387
56b3d975	388	static const struct seq_operations nflog_seq_ops = {
f6ebe77f HW	389	.start = seq_start,
	390	.next = seq_next,
	391	.stop = seq_stop,
	392	.show = seq_show,
	393	};
	394
	395	static int nflog_open(struct inode inode, struct file file)
	396	{
30e0c6a6 G	397	return seq_open_net(inode, file, &nflog_seq_ops,
30e0c6a6 G	398	sizeof(struct seq_net_private));
f6ebe77f HW	399	}
f6ebe77f HW	400
da7071d7	401	static const struct file_operations nflog_file_ops = {
f6ebe77f HW	402	.owner = THIS_MODULE,
	403	.open = nflog_open,
	404	.read = seq_read,
	405	.llseek = seq_lseek,
30e0c6a6	406	.release = seq_release_net,
f6ebe77f HW	407	};
f6ebe77f HW	408
17625274	409
f6ebe77f HW	410	#endif /* PROC_FS */
f6ebe77f HW	411
17625274	412	#ifdef CONFIG_SYSCTL
17625274 EL	413	static char nf_log_sysctl_fnames[NFPROTO_NUMPROTO-NFPROTO_UNSPEC][3];
17625274 EL	414	static struct ctl_table nf_log_sysctl_table[NFPROTO_NUMPROTO+1];
f6ebe77f	415
fe2c6338	416	static int nf_log_proc_dostring(struct ctl_table *table, int write,
24955619	417	void __user buffer, size_t lenp, loff_t *ppos)
17625274 EL	418	{
17625274 EL	419	const struct nf_logger *logger;
24955619	420	char buf[NFLOGGER_NAME_LEN];
17625274 EL	421	int r = 0;
17625274 EL	422	int tindex = (unsigned long)table->extra1;
30e0c6a6	423	struct net *net = current->nsproxy->net_ns;
17625274 EL	424
17625274 EL	425	if (write) {
c6ac37d8 PT	426	struct ctl_table tmp = *table;
	427
	428	tmp.data = buf;
	429	r = proc_dostring(&tmp, write, buffer, lenp, ppos);
	430	if (r)
	431	return r;
24955619 PM	432
24955619 PM	433	if (!strcmp(buf, "NONE")) {
30e0c6a6	434	nf_log_unbind_pf(net, tindex);
17625274 EL	435	return 0;
	436	}
	437	mutex_lock(&nf_log_mutex);
24955619	438	logger = __find_logger(tindex, buf);
17625274 EL	439	if (logger == NULL) {
	440	mutex_unlock(&nf_log_mutex);
	441	return -ENOENT;
	442	}
30e0c6a6	443	rcu_assign_pointer(net->nf.nf_loggers[tindex], logger);
17625274 EL	444	mutex_unlock(&nf_log_mutex);
17625274 EL	445	} else {
266d07cb	446	mutex_lock(&nf_log_mutex);
0c26ed1c	447	logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
17625274 EL	448	if (!logger)
	449	table->data = "NONE";
	450	else
	451	table->data = logger->name;
8d65af78	452	r = proc_dostring(table, write, buffer, lenp, ppos);
266d07cb	453	mutex_unlock(&nf_log_mutex);
17625274 EL	454	}
	455
	456	return r;
	457	}
	458
30e0c6a6	459	static int netfilter_log_sysctl_init(struct net *net)
f6ebe77f	460	{
ca735b3a	461	int i;
30e0c6a6 G	462	struct ctl_table *table;
	463
	464	table = nf_log_sysctl_table;
	465	if (!net_eq(net, &init_net)) {
	466	table = kmemdup(nf_log_sysctl_table,
	467	sizeof(nf_log_sysctl_table),
	468	GFP_KERNEL);
	469	if (!table)
	470	goto err_alloc;
	471	} else {
	472	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
	473	snprintf(nf_log_sysctl_fnames[i],
	474	3, "%d", i);
	475	nf_log_sysctl_table[i].procname =
	476	nf_log_sysctl_fnames[i];
	477	nf_log_sysctl_table[i].data = NULL;
8aefc4d1	478	nf_log_sysctl_table[i].maxlen = NFLOGGER_NAME_LEN;
30e0c6a6 G	479	nf_log_sysctl_table[i].mode = 0644;
	480	nf_log_sysctl_table[i].proc_handler =
	481	nf_log_proc_dostring;
	482	nf_log_sysctl_table[i].extra1 =
	483	(void *)(unsigned long) i;
	484	}
17625274 EL	485	}
17625274 EL	486
30e0c6a6 G	487	net->nf.nf_log_dir_header = register_net_sysctl(net,
	488	"net/netfilter/nf_log",
	489	table);
	490	if (!net->nf.nf_log_dir_header)
	491	goto err_reg;
17625274 EL	492
17625274 EL	493	return 0;
30e0c6a6 G	494
	495	err_reg:
	496	if (!net_eq(net, &init_net))
	497	kfree(table);
	498	err_alloc:
	499	return -ENOMEM;
	500	}
	501
	502	static void netfilter_log_sysctl_exit(struct net *net)
	503	{
	504	struct ctl_table *table;
	505
	506	table = net->nf.nf_log_dir_header->ctl_table_arg;
	507	unregister_net_sysctl_table(net->nf.nf_log_dir_header);
	508	if (!net_eq(net, &init_net))
	509	kfree(table);
17625274 EL	510	}
17625274 EL	511	#else
30e0c6a6	512	static int netfilter_log_sysctl_init(struct net *net)
17625274 EL	513	{
	514	return 0;
	515	}
30e0c6a6 G	516
	517	static void netfilter_log_sysctl_exit(struct net *net)
	518	{
	519	}
17625274 EL	520	#endif /* CONFIG_SYSCTL */
17625274 EL	521
30e0c6a6	522	static int __net_init nf_log_net_init(struct net *net)
17625274	523	{
30e0c6a6 G	524	int ret = -ENOMEM;
30e0c6a6 G	525
f6ebe77f	526	#ifdef CONFIG_PROC_FS
8eeee8b1	527	if (!proc_create("nf_log", S_IRUGO,
30e0c6a6 G	528	net->nf.proc_netfilter, &nflog_file_ops))
30e0c6a6 G	529	return ret;
62243927	530	#endif
30e0c6a6 G	531	ret = netfilter_log_sysctl_init(net);
	532	if (ret < 0)
	533	goto out_sysctl;
ca735b3a	534
30e0c6a6 G	535	return 0;
	536
	537	out_sysctl:
e778f56e	538	#ifdef CONFIG_PROC_FS
6d11cfdb	539	remove_proc_entry("nf_log", net->nf.proc_netfilter);
e778f56e	540	#endif
30e0c6a6 G	541	return ret;
	542	}
	543
	544	static void __net_exit nf_log_net_exit(struct net *net)
	545	{
	546	netfilter_log_sysctl_exit(net);
e778f56e	547	#ifdef CONFIG_PROC_FS
30e0c6a6	548	remove_proc_entry("nf_log", net->nf.proc_netfilter);
e778f56e	549	#endif
30e0c6a6 G	550	}
	551
	552	static struct pernet_operations nf_log_net_ops = {
	553	.init = nf_log_net_init,
	554	.exit = nf_log_net_exit,
	555	};
	556
	557	int __init netfilter_log_init(void)
	558	{
5962815a	559	return register_pernet_subsys(&nf_log_net_ops);
f6ebe77f	560	}