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

// SPDX-License-Identifier: GPL-2.0-only
#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 NFLOGGER_NAME_LEN		64

int sysctl_nf_log_all_netns __read_mostly;
EXPORT_SYMBOL(sysctl_nf_log_all_netns);

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;
}

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

	if (pf == NFPROTO_UNSPEC || pf >= ARRAY_SIZE(net->nf.nf_loggers))
		return -EOPNOTSUPP;

	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);

	return 0;
}
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);
}
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);

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;
	}

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

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

	seq_puts(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,
};
#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 struct ctl_table_header *nf_log_sysctl_fhdr;

static struct ctl_table nf_log_sysctl_ftable[] = {
	{
		.procname	= "nf_log_all_netns",
		.data		= &sysctl_nf_log_all_netns,
		.maxlen		= sizeof(sysctl_nf_log_all_netns),
		.mode		= 0644,
		.proc_handler	= proc_dointvec,
	},
	{ }
};

static int nf_log_proc_dostring(struct ctl_table *table, int write,
			 void *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 = table->extra2;

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

		/* proc_dostring() can append to existing strings, so we need to
		 * initialize it as an empty string.
		 */
		buf[0] = '\0';
		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 {
		struct ctl_table tmp = *table;

		tmp.data = buf;
		mutex_lock(&nf_log_mutex);
		logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
		if (!logger)
			strlcpy(buf, "NONE", sizeof(buf));
		else
			strlcpy(buf, logger->name, sizeof(buf));
		mutex_unlock(&nf_log_mutex);
		r = proc_dostring(&tmp, write, buffer, lenp, ppos);
	}

	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].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;
		}
		nf_log_sysctl_fhdr = register_net_sysctl(net, "net/netfilter",
							 nf_log_sysctl_ftable);
		if (!nf_log_sysctl_fhdr)
			goto err_freg;
	}

	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
		table[i].extra2 = net;

	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);
	else
		unregister_net_sysctl_table(nf_log_sysctl_fhdr);
err_freg:
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
		unregister_net_sysctl_table(nf_log_sysctl_fhdr);
}
#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_net("nf_log", 0444, net->nf.proc_netfilter,
			&nflog_seq_ops, sizeof(struct seq_net_private)))
		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
457c8996	1	// SPDX-License-Identifier: GPL-2.0-only
f6ebe77f HW	2	#include <linux/kernel.h>
	3	#include <linux/init.h>
	4	#include <linux/module.h>
	5	#include <linux/proc_fs.h>
	6	#include <linux/skbuff.h>
	7	#include <linux/netfilter.h>
bbd86b9f	8	#include <linux/seq_file.h>
f6ebe77f	9	#include <net/protocol.h>
f01ffbd6	10	#include <net/netfilter/nf_log.h>
f6ebe77f HW	11
	12	#include "nf_internals.h"
	13
a5d29264	14	/* Internal logging interface, which relies on the real
f6ebe77f HW	15	LOG target modules */
f6ebe77f HW	16
17625274	17	#define NFLOGGER_NAME_LEN 64
f6ebe77f	18
2851940f MK	19	int sysctl_nf_log_all_netns __read_mostly;
	20	EXPORT_SYMBOL(sysctl_nf_log_all_netns);
	21
5962815a	22	static struct nf_logger __rcu *loggers[NFPROTO_NUMPROTO][NF_LOG_TYPE_MAX] __read_mostly;
9b73534d	23	static DEFINE_MUTEX(nf_log_mutex);
f6ebe77f	24
0c26ed1c ML	25	#define nft_log_dereference(logger) \
	26	rcu_dereference_protected(logger, lockdep_is_held(&nf_log_mutex))
	27
ca735b3a	28	static struct nf_logger __find_logger(int pf, const char str_logger)
f6ebe77f	29	{
5962815a PNA	30	struct nf_logger *log;
	31	int i;
	32
	33	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
	34	if (loggers[pf][i] == NULL)
	35	continue;
f6ebe77f	36
0c26ed1c	37	log = nft_log_dereference(loggers[pf][i]);
18082746	38	if (!strncasecmp(str_logger, log->name, strlen(log->name)))
5962815a	39	return log;
ca735b3a	40	}
d72367b6	41
ca735b3a	42	return NULL;
601e68e1	43	}
f6ebe77f	44
779994fa	45	int nf_log_set(struct net net, u_int8_t pf, const struct nf_logger logger)
30e0c6a6 G	46	{
	47	const struct nf_logger *log;
	48
779994fa GF	49	if (pf == NFPROTO_UNSPEC \|\| pf >= ARRAY_SIZE(net->nf.nf_loggers))
779994fa GF	50	return -EOPNOTSUPP;
30e0c6a6 G	51
30e0c6a6 G	52	mutex_lock(&nf_log_mutex);
0c26ed1c	53	log = nft_log_dereference(net->nf.nf_loggers[pf]);
30e0c6a6 G	54	if (log == NULL)
	55	rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
	56
	57	mutex_unlock(&nf_log_mutex);
779994fa GF	58
779994fa GF	59	return 0;
30e0c6a6 G	60	}
	61	EXPORT_SYMBOL(nf_log_set);
	62
	63	void nf_log_unset(struct net net, const struct nf_logger logger)
	64	{
	65	int i;
	66	const struct nf_logger *log;
	67
30e0c6a6 G	68	mutex_lock(&nf_log_mutex);
30e0c6a6 G	69	for (i = 0; i < NFPROTO_NUMPROTO; i++) {
0c26ed1c	70	log = nft_log_dereference(net->nf.nf_loggers[i]);
30e0c6a6 G	71	if (log == logger)
	72	RCU_INIT_POINTER(net->nf.nf_loggers[i], NULL);
	73	}
	74	mutex_unlock(&nf_log_mutex);
30e0c6a6 G	75	}
	76	EXPORT_SYMBOL(nf_log_unset);
	77
d93cf068	78	/* return EEXIST if the same logger is registered, 0 on success. */
ca735b3a	79	int nf_log_register(u_int8_t pf, struct nf_logger *logger)
f6ebe77f	80	{
b6f0a365	81	int i;
8ac2bde2	82	int ret = 0;
ca735b3a	83
30e0c6a6	84	if (pf >= ARRAY_SIZE(init_net.nf.nf_loggers))
ca735b3a EL	85	return -EINVAL;
ca735b3a EL	86
9b73534d	87	mutex_lock(&nf_log_mutex);
ca735b3a EL	88
ca735b3a EL	89	if (pf == NFPROTO_UNSPEC) {
8ac2bde2 ML	90	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
	91	if (rcu_access_pointer(loggers[i][logger->type])) {
	92	ret = -EEXIST;
	93	goto unlock;
	94	}
	95	}
ca735b3a	96	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
5962815a	97	rcu_assign_pointer(loggers[i][logger->type], logger);
ca735b3a	98	} else {
8ac2bde2 ML	99	if (rcu_access_pointer(loggers[pf][logger->type])) {
	100	ret = -EEXIST;
	101	goto unlock;
	102	}
5962815a	103	rcu_assign_pointer(loggers[pf][logger->type], logger);
ca735b3a EL	104	}
ca735b3a EL	105
8ac2bde2	106	unlock:
9b73534d	107	mutex_unlock(&nf_log_mutex);
8ac2bde2	108	return ret;
f6ebe77f	109	}
ca735b3a	110	EXPORT_SYMBOL(nf_log_register);
f6ebe77f	111
ca735b3a	112	void nf_log_unregister(struct nf_logger *logger)
f6ebe77f	113	{
205ee117	114	const struct nf_logger *log;
f6ebe77f HW	115	int i;
f6ebe77f HW	116
9b73534d	117	mutex_lock(&nf_log_mutex);
205ee117 FW	118	for (i = 0; i < NFPROTO_NUMPROTO; i++) {
	119	log = nft_log_dereference(loggers[i][logger->type]);
	120	if (log == logger)
	121	RCU_INIT_POINTER(loggers[i][logger->type], NULL);
	122	}
9b73534d	123	mutex_unlock(&nf_log_mutex);
ad5001cc	124	synchronize_rcu();
f6ebe77f	125	}
e92ad99c	126	EXPORT_SYMBOL(nf_log_unregister);
f6ebe77f	127
30e0c6a6 G	128	int nf_log_bind_pf(struct net *net, u_int8_t pf,
30e0c6a6 G	129	const struct nf_logger *logger)
ca735b3a	130	{
30e0c6a6	131	if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
9ef0298a	132	return -EINVAL;
ca735b3a EL	133	mutex_lock(&nf_log_mutex);
	134	if (__find_logger(pf, logger->name) == NULL) {
	135	mutex_unlock(&nf_log_mutex);
	136	return -ENOENT;
	137	}
30e0c6a6	138	rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
ca735b3a EL	139	mutex_unlock(&nf_log_mutex);
	140	return 0;
	141	}
	142	EXPORT_SYMBOL(nf_log_bind_pf);
	143
30e0c6a6	144	void nf_log_unbind_pf(struct net *net, u_int8_t pf)
ca735b3a	145	{
30e0c6a6	146	if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
9ef0298a	147	return;
ca735b3a	148	mutex_lock(&nf_log_mutex);
30e0c6a6	149	RCU_INIT_POINTER(net->nf.nf_loggers[pf], NULL);
ca735b3a EL	150	mutex_unlock(&nf_log_mutex);
	151	}
	152	EXPORT_SYMBOL(nf_log_unbind_pf);
	153
fab4085f PNA	154	int nf_logger_find_get(int pf, enum nf_log_type type)
	155	{
	156	struct nf_logger *logger;
	157	int ret = -ENOENT;
	158
f3bb5333 LZ	159	if (pf == NFPROTO_INET) {
	160	ret = nf_logger_find_get(NFPROTO_IPV4, type);
	161	if (ret < 0)
	162	return ret;
	163
	164	ret = nf_logger_find_get(NFPROTO_IPV6, type);
	165	if (ret < 0) {
	166	nf_logger_put(NFPROTO_IPV4, type);
	167	return ret;
	168	}
	169
	170	return 0;
	171	}
	172
fab4085f PNA	173	rcu_read_lock();
	174	logger = rcu_dereference(loggers[pf][type]);
	175	if (logger == NULL)
	176	goto out;
	177
7e53e7f8	178	if (try_module_get(logger->me))
fab4085f PNA	179	ret = 0;
	180	out:
	181	rcu_read_unlock();
	182	return ret;
	183	}
	184	EXPORT_SYMBOL_GPL(nf_logger_find_get);
	185
	186	void nf_logger_put(int pf, enum nf_log_type type)
	187	{
	188	struct nf_logger *logger;
	189
f3bb5333 LZ	190	if (pf == NFPROTO_INET) {
	191	nf_logger_put(NFPROTO_IPV4, type);
	192	nf_logger_put(NFPROTO_IPV6, type);
	193	return;
	194	}
	195
fab4085f PNA	196	BUG_ON(loggers[pf][type] == NULL);
	197
	198	rcu_read_lock();
	199	logger = rcu_dereference(loggers[pf][type]);
	200	module_put(logger->me);
	201	rcu_read_unlock();
	202	}
	203	EXPORT_SYMBOL_GPL(nf_logger_put);
	204
30e0c6a6 G	205	void nf_log_packet(struct net *net,
30e0c6a6 G	206	u_int8_t pf,
f6ebe77f HW	207	unsigned int hooknum,
	208	const struct sk_buff *skb,
	209	const struct net_device *in,
	210	const struct net_device *out,
7b2f9631	211	const struct nf_loginfo *loginfo,
f6ebe77f HW	212	const char *fmt, ...)
	213	{
	214	va_list args;
	215	char prefix[NF_LOG_PREFIXLEN];
7b2f9631	216	const struct nf_logger *logger;
601e68e1	217
f6ebe77f	218	rcu_read_lock();
fab4085f PNA	219	if (loginfo != NULL)
	220	logger = rcu_dereference(loggers[pf][loginfo->type]);
	221	else
	222	logger = rcu_dereference(net->nf.nf_loggers[pf]);
	223
f6ebe77f HW	224	if (logger) {
	225	va_start(args, fmt);
	226	vsnprintf(prefix, sizeof(prefix), fmt, args);
	227	va_end(args);
8cdb46da	228	logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
f6ebe77f HW	229	}
	230	rcu_read_unlock();
	231	}
	232	EXPORT_SYMBOL(nf_log_packet);
	233
4017a7ee PNA	234	void nf_log_trace(struct net *net,
	235	u_int8_t pf,
	236	unsigned int hooknum,
	237	const struct sk_buff *skb,
	238	const struct net_device *in,
	239	const struct net_device *out,
	240	const struct nf_loginfo loginfo, const char fmt, ...)
	241	{
	242	va_list args;
	243	char prefix[NF_LOG_PREFIXLEN];
	244	const struct nf_logger *logger;
	245
	246	rcu_read_lock();
	247	logger = rcu_dereference(net->nf.nf_loggers[pf]);
	248	if (logger) {
	249	va_start(args, fmt);
	250	vsnprintf(prefix, sizeof(prefix), fmt, args);
	251	va_end(args);
	252	logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
	253	}
	254	rcu_read_unlock();
	255	}
	256	EXPORT_SYMBOL(nf_log_trace);
	257
27fd8d90 PNA	258	#define S_SIZE (1024 - (sizeof(unsigned int) + 1))
	259
	260	struct nf_log_buf {
	261	unsigned int count;
	262	char buf[S_SIZE + 1];
	263	};
	264	static struct nf_log_buf emergency, *emergency_ptr = &emergency;
	265
	266	__printf(2, 3) int nf_log_buf_add(struct nf_log_buf m, const char f, ...)
	267	{
	268	va_list args;
	269	int len;
	270
	271	if (likely(m->count < S_SIZE)) {
	272	va_start(args, f);
	273	len = vsnprintf(m->buf + m->count, S_SIZE - m->count, f, args);
	274	va_end(args);
	275	if (likely(m->count + len < S_SIZE)) {
	276	m->count += len;
	277	return 0;
	278	}
	279	}
	280	m->count = S_SIZE;
	281	printk_once(KERN_ERR KBUILD_MODNAME " please increase S_SIZE\n");
	282	return -1;
	283	}
	284	EXPORT_SYMBOL_GPL(nf_log_buf_add);
	285
	286	struct nf_log_buf *nf_log_buf_open(void)
	287	{
	288	struct nf_log_buf m = kmalloc(sizeof(m), GFP_ATOMIC);
	289
	290	if (unlikely(!m)) {
	291	local_bh_disable();
	292	do {
	293	m = xchg(&emergency_ptr, NULL);
	294	} while (!m);
	295	}
	296	m->count = 0;
	297	return m;
	298	}
	299	EXPORT_SYMBOL_GPL(nf_log_buf_open);
	300
	301	void nf_log_buf_close(struct nf_log_buf *m)
	302	{
	303	m->buf[m->count] = 0;
	304	printk("%s\n", m->buf);
	305
	306	if (likely(m != &emergency))
	307	kfree(m);
	308	else {
	309	emergency_ptr = m;
	310	local_bh_enable();
	311	}
	312	}
	313	EXPORT_SYMBOL_GPL(nf_log_buf_close);
	314
f6ebe77f HW	315	#ifdef CONFIG_PROC_FS
	316	static void seq_start(struct seq_file seq, loff_t *pos)
	317	{
30e0c6a6 G	318	struct net *net = seq_file_net(seq);
30e0c6a6 G	319
6440fe05	320	mutex_lock(&nf_log_mutex);
f6ebe77f	321
30e0c6a6	322	if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
f6ebe77f HW	323	return NULL;
	324
	325	return pos;
	326	}
	327
	328	static void seq_next(struct seq_file s, void v, loff_t pos)
	329	{
30e0c6a6 G	330	struct net *net = seq_file_net(s);
30e0c6a6 G	331
f6ebe77f HW	332	(*pos)++;
f6ebe77f HW	333
30e0c6a6	334	if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
f6ebe77f HW	335	return NULL;
	336
	337	return pos;
	338	}
	339
	340	static void seq_stop(struct seq_file s, void v)
	341	{
6440fe05	342	mutex_unlock(&nf_log_mutex);
f6ebe77f HW	343	}
	344
	345	static int seq_show(struct seq_file s, void v)
	346	{
	347	loff_t *pos = v;
	348	const struct nf_logger *logger;
e71456ae	349	int i;
30e0c6a6	350	struct net *net = seq_file_net(s);
f6ebe77f	351
0c26ed1c	352	logger = nft_log_dereference(net->nf.nf_loggers[*pos]);
f6ebe77f HW	353
f6ebe77f HW	354	if (!logger)
e71456ae	355	seq_printf(s, "%2lld NONE (", *pos);
c7a913cd	356	else
e71456ae	357	seq_printf(s, "%2lld %s (", *pos, logger->name);
c7a913cd	358
e71456ae SRRH	359	if (seq_has_overflowed(s))
e71456ae SRRH	360	return -ENOSPC;
c7a913cd	361
5962815a PNA	362	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
	363	if (loggers[*pos][i] == NULL)
	364	continue;
	365
0c26ed1c	366	logger = nft_log_dereference(loggers[*pos][i]);
eca27f14	367	seq_puts(s, logger->name);
e71456ae	368	if (i == 0 && loggers[*pos][i + 1] != NULL)
cdec2685	369	seq_puts(s, ",");
e71456ae SRRH	370
	371	if (seq_has_overflowed(s))
	372	return -ENOSPC;
c7a913cd	373	}
601e68e1	374
cdec2685	375	seq_puts(s, ")\n");
e71456ae SRRH	376
	377	if (seq_has_overflowed(s))
	378	return -ENOSPC;
	379	return 0;
f6ebe77f HW	380	}
f6ebe77f HW	381
56b3d975	382	static const struct seq_operations nflog_seq_ops = {
f6ebe77f HW	383	.start = seq_start,
	384	.next = seq_next,
	385	.stop = seq_stop,
	386	.show = seq_show,
	387	};
f6ebe77f HW	388	#endif /* PROC_FS */
f6ebe77f HW	389
17625274	390	#ifdef CONFIG_SYSCTL
17625274 EL	391	static char nf_log_sysctl_fnames[NFPROTO_NUMPROTO-NFPROTO_UNSPEC][3];
17625274 EL	392	static struct ctl_table nf_log_sysctl_table[NFPROTO_NUMPROTO+1];
2851940f MK	393	static struct ctl_table_header *nf_log_sysctl_fhdr;
	394
	395	static struct ctl_table nf_log_sysctl_ftable[] = {
	396	{
	397	.procname = "nf_log_all_netns",
	398	.data = &sysctl_nf_log_all_netns,
	399	.maxlen = sizeof(sysctl_nf_log_all_netns),
	400	.mode = 0644,
	401	.proc_handler = proc_dointvec,
	402	},
	403	{ }
	404	};
f6ebe77f	405
fe2c6338	406	static int nf_log_proc_dostring(struct ctl_table *table, int write,
32927393	407	void buffer, size_t lenp, loff_t *ppos)
17625274 EL	408	{
17625274 EL	409	const struct nf_logger *logger;
24955619	410	char buf[NFLOGGER_NAME_LEN];
17625274 EL	411	int r = 0;
17625274 EL	412	int tindex = (unsigned long)table->extra1;
dbb5918c	413	struct net *net = table->extra2;
17625274 EL	414
17625274 EL	415	if (write) {
c6ac37d8 PT	416	struct ctl_table tmp = *table;
c6ac37d8 PT	417
dffd22ae JH	418	/* proc_dostring() can append to existing strings, so we need to
	419	* initialize it as an empty string.
	420	*/
	421	buf[0] = '\0';
c6ac37d8 PT	422	tmp.data = buf;
	423	r = proc_dostring(&tmp, write, buffer, lenp, ppos);
	424	if (r)
	425	return r;
24955619 PM	426
24955619 PM	427	if (!strcmp(buf, "NONE")) {
30e0c6a6	428	nf_log_unbind_pf(net, tindex);
17625274 EL	429	return 0;
	430	}
	431	mutex_lock(&nf_log_mutex);
24955619	432	logger = __find_logger(tindex, buf);
17625274 EL	433	if (logger == NULL) {
	434	mutex_unlock(&nf_log_mutex);
	435	return -ENOENT;
	436	}
30e0c6a6	437	rcu_assign_pointer(net->nf.nf_loggers[tindex], logger);
17625274 EL	438	mutex_unlock(&nf_log_mutex);
17625274 EL	439	} else {
ce00bf07 JH	440	struct ctl_table tmp = *table;
	441
	442	tmp.data = buf;
266d07cb	443	mutex_lock(&nf_log_mutex);
0c26ed1c	444	logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
17625274	445	if (!logger)
ce00bf07	446	strlcpy(buf, "NONE", sizeof(buf));
17625274	447	else
ce00bf07	448	strlcpy(buf, logger->name, sizeof(buf));
266d07cb	449	mutex_unlock(&nf_log_mutex);
ce00bf07	450	r = proc_dostring(&tmp, write, buffer, lenp, ppos);
17625274 EL	451	}
	452
	453	return r;
	454	}
	455
30e0c6a6	456	static int netfilter_log_sysctl_init(struct net *net)
f6ebe77f	457	{
ca735b3a	458	int i;
30e0c6a6 G	459	struct ctl_table *table;
	460
	461	table = nf_log_sysctl_table;
	462	if (!net_eq(net, &init_net)) {
	463	table = kmemdup(nf_log_sysctl_table,
	464	sizeof(nf_log_sysctl_table),
	465	GFP_KERNEL);
	466	if (!table)
	467	goto err_alloc;
	468	} else {
	469	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
	470	snprintf(nf_log_sysctl_fnames[i],
	471	3, "%d", i);
	472	nf_log_sysctl_table[i].procname =
	473	nf_log_sysctl_fnames[i];
8aefc4d1	474	nf_log_sysctl_table[i].maxlen = NFLOGGER_NAME_LEN;
30e0c6a6 G	475	nf_log_sysctl_table[i].mode = 0644;
	476	nf_log_sysctl_table[i].proc_handler =
	477	nf_log_proc_dostring;
	478	nf_log_sysctl_table[i].extra1 =
	479	(void *)(unsigned long) i;
	480	}
2851940f MK	481	nf_log_sysctl_fhdr = register_net_sysctl(net, "net/netfilter",
	482	nf_log_sysctl_ftable);
	483	if (!nf_log_sysctl_fhdr)
	484	goto err_freg;
17625274 EL	485	}
17625274 EL	486
dbb5918c JH	487	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
	488	table[i].extra2 = net;
	489
30e0c6a6 G	490	net->nf.nf_log_dir_header = register_net_sysctl(net,
	491	"net/netfilter/nf_log",
	492	table);
	493	if (!net->nf.nf_log_dir_header)
	494	goto err_reg;
17625274 EL	495
17625274 EL	496	return 0;
30e0c6a6 G	497
	498	err_reg:
	499	if (!net_eq(net, &init_net))
	500	kfree(table);
2851940f MK	501	else
	502	unregister_net_sysctl_table(nf_log_sysctl_fhdr);
	503	err_freg:
30e0c6a6 G	504	err_alloc:
	505	return -ENOMEM;
	506	}
	507
	508	static void netfilter_log_sysctl_exit(struct net *net)
	509	{
	510	struct ctl_table *table;
	511
	512	table = net->nf.nf_log_dir_header->ctl_table_arg;
	513	unregister_net_sysctl_table(net->nf.nf_log_dir_header);
	514	if (!net_eq(net, &init_net))
	515	kfree(table);
2851940f MK	516	else
2851940f MK	517	unregister_net_sysctl_table(nf_log_sysctl_fhdr);
17625274 EL	518	}
17625274 EL	519	#else
30e0c6a6	520	static int netfilter_log_sysctl_init(struct net *net)
17625274 EL	521	{
	522	return 0;
	523	}
30e0c6a6 G	524
	525	static void netfilter_log_sysctl_exit(struct net *net)
	526	{
	527	}
17625274 EL	528	#endif /* CONFIG_SYSCTL */
17625274 EL	529
30e0c6a6	530	static int __net_init nf_log_net_init(struct net *net)
17625274	531	{
30e0c6a6 G	532	int ret = -ENOMEM;
30e0c6a6 G	533
f6ebe77f	534	#ifdef CONFIG_PROC_FS
c3506372 CH	535	if (!proc_create_net("nf_log", 0444, net->nf.proc_netfilter,
c3506372 CH	536	&nflog_seq_ops, sizeof(struct seq_net_private)))
30e0c6a6	537	return ret;
62243927	538	#endif
30e0c6a6 G	539	ret = netfilter_log_sysctl_init(net);
	540	if (ret < 0)
	541	goto out_sysctl;
ca735b3a	542
30e0c6a6 G	543	return 0;
	544
	545	out_sysctl:
e778f56e	546	#ifdef CONFIG_PROC_FS
6d11cfdb	547	remove_proc_entry("nf_log", net->nf.proc_netfilter);
e778f56e	548	#endif
30e0c6a6 G	549	return ret;
	550	}
	551
	552	static void __net_exit nf_log_net_exit(struct net *net)
	553	{
	554	netfilter_log_sysctl_exit(net);
e778f56e	555	#ifdef CONFIG_PROC_FS
30e0c6a6	556	remove_proc_entry("nf_log", net->nf.proc_netfilter);
e778f56e	557	#endif
30e0c6a6 G	558	}
	559
	560	static struct pernet_operations nf_log_net_ops = {
	561	.init = nf_log_net_init,
	562	.exit = nf_log_net_exit,
	563	};
	564
	565	int __init netfilter_log_init(void)
	566	{
5962815a	567	return register_pernet_subsys(&nf_log_net_ops);
f6ebe77f	568	}