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>
7 #include <linux/seq_file.h>
8 #include <net/protocol.h>
9 #include <net/netfilter/nf_log.h>
11 #include "nf_internals.h"
13 /* Internal logging interface, which relies on the real
16 #define NF_LOG_PREFIXLEN 128
17 #define NFLOGGER_NAME_LEN 64
19 static struct nf_logger __rcu *loggers[NFPROTO_NUMPROTO][NF_LOG_TYPE_MAX] __read_mostly;
20 static DEFINE_MUTEX(nf_log_mutex);
22 #define nft_log_dereference(logger) \
23 rcu_dereference_protected(logger, lockdep_is_held(&nf_log_mutex))
25 static struct nf_logger *__find_logger(int pf, const char *str_logger)
27 struct nf_logger *log;
30 for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
31 if (loggers[pf][i] == NULL)
34 log = nft_log_dereference(loggers[pf][i]);
35 if (!strncasecmp(str_logger, log->name, strlen(log->name)))
42 void nf_log_set(struct net *net, u_int8_t pf, const struct nf_logger *logger)
44 const struct nf_logger *log;
46 if (pf == NFPROTO_UNSPEC)
49 mutex_lock(&nf_log_mutex);
50 log = nft_log_dereference(net->nf.nf_loggers[pf]);
52 rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
54 mutex_unlock(&nf_log_mutex);
56 EXPORT_SYMBOL(nf_log_set);
58 void nf_log_unset(struct net *net, const struct nf_logger *logger)
61 const struct nf_logger *log;
63 mutex_lock(&nf_log_mutex);
64 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
65 log = nft_log_dereference(net->nf.nf_loggers[i]);
67 RCU_INIT_POINTER(net->nf.nf_loggers[i], NULL);
69 mutex_unlock(&nf_log_mutex);
72 EXPORT_SYMBOL(nf_log_unset);
74 /* return EEXIST if the same logger is registered, 0 on success. */
75 int nf_log_register(u_int8_t pf, struct nf_logger *logger)
80 if (pf >= ARRAY_SIZE(init_net.nf.nf_loggers))
83 mutex_lock(&nf_log_mutex);
85 if (pf == NFPROTO_UNSPEC) {
86 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
87 if (rcu_access_pointer(loggers[i][logger->type])) {
92 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
93 rcu_assign_pointer(loggers[i][logger->type], logger);
95 if (rcu_access_pointer(loggers[pf][logger->type])) {
99 rcu_assign_pointer(loggers[pf][logger->type], logger);
103 mutex_unlock(&nf_log_mutex);
106 EXPORT_SYMBOL(nf_log_register);
108 void nf_log_unregister(struct nf_logger *logger)
112 mutex_lock(&nf_log_mutex);
113 for (i = 0; i < NFPROTO_NUMPROTO; i++)
114 RCU_INIT_POINTER(loggers[i][logger->type], NULL);
115 mutex_unlock(&nf_log_mutex);
117 EXPORT_SYMBOL(nf_log_unregister);
119 int nf_log_bind_pf(struct net *net, u_int8_t pf,
120 const struct nf_logger *logger)
122 if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
124 mutex_lock(&nf_log_mutex);
125 if (__find_logger(pf, logger->name) == NULL) {
126 mutex_unlock(&nf_log_mutex);
129 rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
130 mutex_unlock(&nf_log_mutex);
133 EXPORT_SYMBOL(nf_log_bind_pf);
135 void nf_log_unbind_pf(struct net *net, u_int8_t pf)
137 if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
139 mutex_lock(&nf_log_mutex);
140 RCU_INIT_POINTER(net->nf.nf_loggers[pf], NULL);
141 mutex_unlock(&nf_log_mutex);
143 EXPORT_SYMBOL(nf_log_unbind_pf);
145 void nf_logger_request_module(int pf, enum nf_log_type type)
147 if (loggers[pf][type] == NULL)
148 request_module("nf-logger-%u-%u", pf, type);
150 EXPORT_SYMBOL_GPL(nf_logger_request_module);
152 int nf_logger_find_get(int pf, enum nf_log_type type)
154 struct nf_logger *logger;
157 if (rcu_access_pointer(loggers[pf][type]) == NULL)
158 request_module("nf-logger-%u-%u", pf, type);
161 logger = rcu_dereference(loggers[pf][type]);
165 if (logger && try_module_get(logger->me))
171 EXPORT_SYMBOL_GPL(nf_logger_find_get);
173 void nf_logger_put(int pf, enum nf_log_type type)
175 struct nf_logger *logger;
177 BUG_ON(loggers[pf][type] == NULL);
180 logger = rcu_dereference(loggers[pf][type]);
181 module_put(logger->me);
184 EXPORT_SYMBOL_GPL(nf_logger_put);
186 void nf_log_packet(struct net *net,
188 unsigned int hooknum,
189 const struct sk_buff *skb,
190 const struct net_device *in,
191 const struct net_device *out,
192 const struct nf_loginfo *loginfo,
193 const char *fmt, ...)
196 char prefix[NF_LOG_PREFIXLEN];
197 const struct nf_logger *logger;
201 logger = rcu_dereference(loggers[pf][loginfo->type]);
203 logger = rcu_dereference(net->nf.nf_loggers[pf]);
207 vsnprintf(prefix, sizeof(prefix), fmt, args);
209 logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
213 EXPORT_SYMBOL(nf_log_packet);
215 void nf_log_trace(struct net *net,
217 unsigned int hooknum,
218 const struct sk_buff *skb,
219 const struct net_device *in,
220 const struct net_device *out,
221 const struct nf_loginfo *loginfo, const char *fmt, ...)
224 char prefix[NF_LOG_PREFIXLEN];
225 const struct nf_logger *logger;
228 logger = rcu_dereference(net->nf.nf_loggers[pf]);
231 vsnprintf(prefix, sizeof(prefix), fmt, args);
233 logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
237 EXPORT_SYMBOL(nf_log_trace);
239 #define S_SIZE (1024 - (sizeof(unsigned int) + 1))
243 char buf[S_SIZE + 1];
245 static struct nf_log_buf emergency, *emergency_ptr = &emergency;
247 __printf(2, 3) int nf_log_buf_add(struct nf_log_buf *m, const char *f, ...)
252 if (likely(m->count < S_SIZE)) {
254 len = vsnprintf(m->buf + m->count, S_SIZE - m->count, f, args);
256 if (likely(m->count + len < S_SIZE)) {
262 printk_once(KERN_ERR KBUILD_MODNAME " please increase S_SIZE\n");
265 EXPORT_SYMBOL_GPL(nf_log_buf_add);
267 struct nf_log_buf *nf_log_buf_open(void)
269 struct nf_log_buf *m = kmalloc(sizeof(*m), GFP_ATOMIC);
274 m = xchg(&emergency_ptr, NULL);
280 EXPORT_SYMBOL_GPL(nf_log_buf_open);
282 void nf_log_buf_close(struct nf_log_buf *m)
284 m->buf[m->count] = 0;
285 printk("%s\n", m->buf);
287 if (likely(m != &emergency))
294 EXPORT_SYMBOL_GPL(nf_log_buf_close);
296 #ifdef CONFIG_PROC_FS
297 static void *seq_start(struct seq_file *seq, loff_t *pos)
299 struct net *net = seq_file_net(seq);
301 mutex_lock(&nf_log_mutex);
303 if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
309 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
311 struct net *net = seq_file_net(s);
315 if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
321 static void seq_stop(struct seq_file *s, void *v)
323 mutex_unlock(&nf_log_mutex);
326 static int seq_show(struct seq_file *s, void *v)
329 const struct nf_logger *logger;
331 struct net *net = seq_file_net(s);
333 logger = nft_log_dereference(net->nf.nf_loggers[*pos]);
336 seq_printf(s, "%2lld NONE (", *pos);
338 seq_printf(s, "%2lld %s (", *pos, logger->name);
340 if (seq_has_overflowed(s))
343 for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
344 if (loggers[*pos][i] == NULL)
347 logger = nft_log_dereference(loggers[*pos][i]);
348 seq_printf(s, "%s", logger->name);
349 if (i == 0 && loggers[*pos][i + 1] != NULL)
352 if (seq_has_overflowed(s))
356 seq_printf(s, ")\n");
358 if (seq_has_overflowed(s))
363 static const struct seq_operations nflog_seq_ops = {
370 static int nflog_open(struct inode *inode, struct file *file)
372 return seq_open_net(inode, file, &nflog_seq_ops,
373 sizeof(struct seq_net_private));
376 static const struct file_operations nflog_file_ops = {
377 .owner = THIS_MODULE,
381 .release = seq_release_net,
388 static char nf_log_sysctl_fnames[NFPROTO_NUMPROTO-NFPROTO_UNSPEC][3];
389 static struct ctl_table nf_log_sysctl_table[NFPROTO_NUMPROTO+1];
391 static int nf_log_proc_dostring(struct ctl_table *table, int write,
392 void __user *buffer, size_t *lenp, loff_t *ppos)
394 const struct nf_logger *logger;
395 char buf[NFLOGGER_NAME_LEN];
398 int tindex = (unsigned long)table->extra1;
399 struct net *net = current->nsproxy->net_ns;
402 if (size > sizeof(buf))
404 if (copy_from_user(buf, buffer, size))
407 if (!strcmp(buf, "NONE")) {
408 nf_log_unbind_pf(net, tindex);
411 mutex_lock(&nf_log_mutex);
412 logger = __find_logger(tindex, buf);
413 if (logger == NULL) {
414 mutex_unlock(&nf_log_mutex);
417 rcu_assign_pointer(net->nf.nf_loggers[tindex], logger);
418 mutex_unlock(&nf_log_mutex);
420 mutex_lock(&nf_log_mutex);
421 logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
423 table->data = "NONE";
425 table->data = logger->name;
426 r = proc_dostring(table, write, buffer, lenp, ppos);
427 mutex_unlock(&nf_log_mutex);
433 static int netfilter_log_sysctl_init(struct net *net)
436 struct ctl_table *table;
438 table = nf_log_sysctl_table;
439 if (!net_eq(net, &init_net)) {
440 table = kmemdup(nf_log_sysctl_table,
441 sizeof(nf_log_sysctl_table),
446 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
447 snprintf(nf_log_sysctl_fnames[i],
449 nf_log_sysctl_table[i].procname =
450 nf_log_sysctl_fnames[i];
451 nf_log_sysctl_table[i].data = NULL;
452 nf_log_sysctl_table[i].maxlen = NFLOGGER_NAME_LEN;
453 nf_log_sysctl_table[i].mode = 0644;
454 nf_log_sysctl_table[i].proc_handler =
455 nf_log_proc_dostring;
456 nf_log_sysctl_table[i].extra1 =
457 (void *)(unsigned long) i;
461 net->nf.nf_log_dir_header = register_net_sysctl(net,
462 "net/netfilter/nf_log",
464 if (!net->nf.nf_log_dir_header)
470 if (!net_eq(net, &init_net))
476 static void netfilter_log_sysctl_exit(struct net *net)
478 struct ctl_table *table;
480 table = net->nf.nf_log_dir_header->ctl_table_arg;
481 unregister_net_sysctl_table(net->nf.nf_log_dir_header);
482 if (!net_eq(net, &init_net))
486 static int netfilter_log_sysctl_init(struct net *net)
491 static void netfilter_log_sysctl_exit(struct net *net)
494 #endif /* CONFIG_SYSCTL */
496 static int __net_init nf_log_net_init(struct net *net)
500 #ifdef CONFIG_PROC_FS
501 if (!proc_create("nf_log", S_IRUGO,
502 net->nf.proc_netfilter, &nflog_file_ops))
505 ret = netfilter_log_sysctl_init(net);
512 #ifdef CONFIG_PROC_FS
513 remove_proc_entry("nf_log", net->nf.proc_netfilter);
518 static void __net_exit nf_log_net_exit(struct net *net)
520 netfilter_log_sysctl_exit(net);
521 #ifdef CONFIG_PROC_FS
522 remove_proc_entry("nf_log", net->nf.proc_netfilter);
526 static struct pernet_operations nf_log_net_ops = {
527 .init = nf_log_net_init,
528 .exit = nf_log_net_exit,
531 int __init netfilter_log_init(void)
533 return register_pernet_subsys(&nf_log_net_ops);