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 int 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 || pf >= ARRAY_SIZE(net->nf.nf_loggers))
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);
58 EXPORT_SYMBOL(nf_log_set);
60 void nf_log_unset(struct net *net, const struct nf_logger *logger)
63 const struct nf_logger *log;
65 mutex_lock(&nf_log_mutex);
66 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
67 log = nft_log_dereference(net->nf.nf_loggers[i]);
69 RCU_INIT_POINTER(net->nf.nf_loggers[i], NULL);
71 mutex_unlock(&nf_log_mutex);
74 EXPORT_SYMBOL(nf_log_unset);
76 /* return EEXIST if the same logger is registered, 0 on success. */
77 int nf_log_register(u_int8_t pf, struct nf_logger *logger)
82 if (pf >= ARRAY_SIZE(init_net.nf.nf_loggers))
85 mutex_lock(&nf_log_mutex);
87 if (pf == NFPROTO_UNSPEC) {
88 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
89 if (rcu_access_pointer(loggers[i][logger->type])) {
94 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
95 rcu_assign_pointer(loggers[i][logger->type], logger);
97 if (rcu_access_pointer(loggers[pf][logger->type])) {
101 rcu_assign_pointer(loggers[pf][logger->type], logger);
105 mutex_unlock(&nf_log_mutex);
108 EXPORT_SYMBOL(nf_log_register);
110 void nf_log_unregister(struct nf_logger *logger)
112 const struct nf_logger *log;
115 mutex_lock(&nf_log_mutex);
116 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
117 log = nft_log_dereference(loggers[i][logger->type]);
119 RCU_INIT_POINTER(loggers[i][logger->type], NULL);
121 mutex_unlock(&nf_log_mutex);
124 EXPORT_SYMBOL(nf_log_unregister);
126 int nf_log_bind_pf(struct net *net, u_int8_t pf,
127 const struct nf_logger *logger)
129 if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
131 mutex_lock(&nf_log_mutex);
132 if (__find_logger(pf, logger->name) == NULL) {
133 mutex_unlock(&nf_log_mutex);
136 rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
137 mutex_unlock(&nf_log_mutex);
140 EXPORT_SYMBOL(nf_log_bind_pf);
142 void nf_log_unbind_pf(struct net *net, u_int8_t pf)
144 if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
146 mutex_lock(&nf_log_mutex);
147 RCU_INIT_POINTER(net->nf.nf_loggers[pf], NULL);
148 mutex_unlock(&nf_log_mutex);
150 EXPORT_SYMBOL(nf_log_unbind_pf);
152 void nf_logger_request_module(int pf, enum nf_log_type type)
154 if (loggers[pf][type] == NULL)
155 request_module("nf-logger-%u-%u", pf, type);
157 EXPORT_SYMBOL_GPL(nf_logger_request_module);
159 int nf_logger_find_get(int pf, enum nf_log_type type)
161 struct nf_logger *logger;
164 if (pf == NFPROTO_INET) {
165 ret = nf_logger_find_get(NFPROTO_IPV4, type);
169 ret = nf_logger_find_get(NFPROTO_IPV6, type);
171 nf_logger_put(NFPROTO_IPV4, type);
178 if (rcu_access_pointer(loggers[pf][type]) == NULL)
179 request_module("nf-logger-%u-%u", pf, type);
182 logger = rcu_dereference(loggers[pf][type]);
186 if (try_module_get(logger->me))
192 EXPORT_SYMBOL_GPL(nf_logger_find_get);
194 void nf_logger_put(int pf, enum nf_log_type type)
196 struct nf_logger *logger;
198 if (pf == NFPROTO_INET) {
199 nf_logger_put(NFPROTO_IPV4, type);
200 nf_logger_put(NFPROTO_IPV6, type);
204 BUG_ON(loggers[pf][type] == NULL);
207 logger = rcu_dereference(loggers[pf][type]);
208 module_put(logger->me);
211 EXPORT_SYMBOL_GPL(nf_logger_put);
213 void nf_log_packet(struct net *net,
215 unsigned int hooknum,
216 const struct sk_buff *skb,
217 const struct net_device *in,
218 const struct net_device *out,
219 const struct nf_loginfo *loginfo,
220 const char *fmt, ...)
223 char prefix[NF_LOG_PREFIXLEN];
224 const struct nf_logger *logger;
228 logger = rcu_dereference(loggers[pf][loginfo->type]);
230 logger = rcu_dereference(net->nf.nf_loggers[pf]);
234 vsnprintf(prefix, sizeof(prefix), fmt, args);
236 logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
240 EXPORT_SYMBOL(nf_log_packet);
242 void nf_log_trace(struct net *net,
244 unsigned int hooknum,
245 const struct sk_buff *skb,
246 const struct net_device *in,
247 const struct net_device *out,
248 const struct nf_loginfo *loginfo, const char *fmt, ...)
251 char prefix[NF_LOG_PREFIXLEN];
252 const struct nf_logger *logger;
255 logger = rcu_dereference(net->nf.nf_loggers[pf]);
258 vsnprintf(prefix, sizeof(prefix), fmt, args);
260 logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
264 EXPORT_SYMBOL(nf_log_trace);
266 #define S_SIZE (1024 - (sizeof(unsigned int) + 1))
270 char buf[S_SIZE + 1];
272 static struct nf_log_buf emergency, *emergency_ptr = &emergency;
274 __printf(2, 3) int nf_log_buf_add(struct nf_log_buf *m, const char *f, ...)
279 if (likely(m->count < S_SIZE)) {
281 len = vsnprintf(m->buf + m->count, S_SIZE - m->count, f, args);
283 if (likely(m->count + len < S_SIZE)) {
289 printk_once(KERN_ERR KBUILD_MODNAME " please increase S_SIZE\n");
292 EXPORT_SYMBOL_GPL(nf_log_buf_add);
294 struct nf_log_buf *nf_log_buf_open(void)
296 struct nf_log_buf *m = kmalloc(sizeof(*m), GFP_ATOMIC);
301 m = xchg(&emergency_ptr, NULL);
307 EXPORT_SYMBOL_GPL(nf_log_buf_open);
309 void nf_log_buf_close(struct nf_log_buf *m)
311 m->buf[m->count] = 0;
312 printk("%s\n", m->buf);
314 if (likely(m != &emergency))
321 EXPORT_SYMBOL_GPL(nf_log_buf_close);
323 #ifdef CONFIG_PROC_FS
324 static void *seq_start(struct seq_file *seq, loff_t *pos)
326 struct net *net = seq_file_net(seq);
328 mutex_lock(&nf_log_mutex);
330 if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
336 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
338 struct net *net = seq_file_net(s);
342 if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
348 static void seq_stop(struct seq_file *s, void *v)
350 mutex_unlock(&nf_log_mutex);
353 static int seq_show(struct seq_file *s, void *v)
356 const struct nf_logger *logger;
358 struct net *net = seq_file_net(s);
360 logger = nft_log_dereference(net->nf.nf_loggers[*pos]);
363 seq_printf(s, "%2lld NONE (", *pos);
365 seq_printf(s, "%2lld %s (", *pos, logger->name);
367 if (seq_has_overflowed(s))
370 for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
371 if (loggers[*pos][i] == NULL)
374 logger = nft_log_dereference(loggers[*pos][i]);
375 seq_printf(s, "%s", logger->name);
376 if (i == 0 && loggers[*pos][i + 1] != NULL)
379 if (seq_has_overflowed(s))
383 seq_printf(s, ")\n");
385 if (seq_has_overflowed(s))
390 static const struct seq_operations nflog_seq_ops = {
397 static int nflog_open(struct inode *inode, struct file *file)
399 return seq_open_net(inode, file, &nflog_seq_ops,
400 sizeof(struct seq_net_private));
403 static const struct file_operations nflog_file_ops = {
404 .owner = THIS_MODULE,
408 .release = seq_release_net,
415 static char nf_log_sysctl_fnames[NFPROTO_NUMPROTO-NFPROTO_UNSPEC][3];
416 static struct ctl_table nf_log_sysctl_table[NFPROTO_NUMPROTO+1];
418 static int nf_log_proc_dostring(struct ctl_table *table, int write,
419 void __user *buffer, size_t *lenp, loff_t *ppos)
421 const struct nf_logger *logger;
422 char buf[NFLOGGER_NAME_LEN];
424 int tindex = (unsigned long)table->extra1;
425 struct net *net = table->extra2;
428 struct ctl_table tmp = *table;
431 r = proc_dostring(&tmp, write, buffer, lenp, ppos);
435 if (!strcmp(buf, "NONE")) {
436 nf_log_unbind_pf(net, tindex);
439 mutex_lock(&nf_log_mutex);
440 logger = __find_logger(tindex, buf);
441 if (logger == NULL) {
442 mutex_unlock(&nf_log_mutex);
445 rcu_assign_pointer(net->nf.nf_loggers[tindex], logger);
446 mutex_unlock(&nf_log_mutex);
448 mutex_lock(&nf_log_mutex);
449 logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
451 table->data = "NONE";
453 table->data = logger->name;
454 r = proc_dostring(table, write, buffer, lenp, ppos);
455 mutex_unlock(&nf_log_mutex);
461 static int netfilter_log_sysctl_init(struct net *net)
464 struct ctl_table *table;
466 table = nf_log_sysctl_table;
467 if (!net_eq(net, &init_net)) {
468 table = kmemdup(nf_log_sysctl_table,
469 sizeof(nf_log_sysctl_table),
474 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
475 snprintf(nf_log_sysctl_fnames[i],
477 nf_log_sysctl_table[i].procname =
478 nf_log_sysctl_fnames[i];
479 nf_log_sysctl_table[i].maxlen = NFLOGGER_NAME_LEN;
480 nf_log_sysctl_table[i].mode = 0644;
481 nf_log_sysctl_table[i].proc_handler =
482 nf_log_proc_dostring;
483 nf_log_sysctl_table[i].extra1 =
484 (void *)(unsigned long) i;
488 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
489 table[i].extra2 = net;
491 net->nf.nf_log_dir_header = register_net_sysctl(net,
492 "net/netfilter/nf_log",
494 if (!net->nf.nf_log_dir_header)
500 if (!net_eq(net, &init_net))
506 static void netfilter_log_sysctl_exit(struct net *net)
508 struct ctl_table *table;
510 table = net->nf.nf_log_dir_header->ctl_table_arg;
511 unregister_net_sysctl_table(net->nf.nf_log_dir_header);
512 if (!net_eq(net, &init_net))
516 static int netfilter_log_sysctl_init(struct net *net)
521 static void netfilter_log_sysctl_exit(struct net *net)
524 #endif /* CONFIG_SYSCTL */
526 static int __net_init nf_log_net_init(struct net *net)
530 #ifdef CONFIG_PROC_FS
531 if (!proc_create("nf_log", S_IRUGO,
532 net->nf.proc_netfilter, &nflog_file_ops))
535 ret = netfilter_log_sysctl_init(net);
542 #ifdef CONFIG_PROC_FS
543 remove_proc_entry("nf_log", net->nf.proc_netfilter);
548 static void __net_exit nf_log_net_exit(struct net *net)
550 netfilter_log_sysctl_exit(net);
551 #ifdef CONFIG_PROC_FS
552 remove_proc_entry("nf_log", net->nf.proc_netfilter);
556 static struct pernet_operations nf_log_net_ops = {
557 .init = nf_log_net_init,
558 .exit = nf_log_net_exit,
561 int __init netfilter_log_init(void)
563 return register_pernet_subsys(&nf_log_net_ops);