1 files changed, 169 insertions, 32 deletions

diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index fa8ae5d2659..8bb998fe098 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -14,58 +14,63 @@
    LOG target modules */
 
 #define NF_LOG_PREFIXLEN		128
+#define NFLOGGER_NAME_LEN		64
 
 static const struct nf_logger *nf_loggers[NFPROTO_NUMPROTO] __read_mostly;
+static struct list_head nf_loggers_l[NFPROTO_NUMPROTO] __read_mostly;
 static DEFINE_MUTEX(nf_log_mutex);
 
-/* return EBUSY if somebody else is registered, EEXIST if the same logger
- * is registred, 0 on success. */
-int nf_log_register(u_int8_t pf, const struct nf_logger *logger)
+static struct nf_logger *__find_logger(int pf, const char *str_logger)
 {
-	int ret;
+	struct nf_logger *t;
 
-	if (pf >= ARRAY_SIZE(nf_loggers))
-		return -EINVAL;
-
-	/* Any setup of logging members must be done before
-	 * substituting pointer. */
-	ret = mutex_lock_interruptible(&nf_log_mutex);
-	if (ret < 0)
-		return ret;
-
-	if (!nf_loggers[pf])
-		rcu_assign_pointer(nf_loggers[pf], logger);
-	else if (nf_loggers[pf] == logger)
-		ret = -EEXIST;
-	else
-		ret = -EBUSY;
+	list_for_each_entry(t, &nf_loggers_l[pf], list[pf]) {
+		if (!strnicmp(str_logger, t->name, strlen(t->name)))
+			return t;
+	}
 
-	mutex_unlock(&nf_log_mutex);
-	return ret;
+	return NULL;
 }
-EXPORT_SYMBOL(nf_log_register);
 
-void nf_log_unregister_pf(u_int8_t pf)
+/* return EEXIST if the same logger is registred, 0 on success. */
+int nf_log_register(u_int8_t pf, struct nf_logger *logger)
 {
+	const struct nf_logger *llog;
+
 	if (pf >= ARRAY_SIZE(nf_loggers))
-		return;
+		return -EINVAL;
+
 	mutex_lock(&nf_log_mutex);
-	rcu_assign_pointer(nf_loggers[pf], NULL);
+
+	if (pf == NFPROTO_UNSPEC) {
+		int i;
+		for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
+			list_add_tail(&(logger->list[i]), &(nf_loggers_l[i]));
+	} else {
+		/* register at end of list to honor first register win */
+		list_add_tail(&logger->list[pf], &nf_loggers_l[pf]);
+		llog = rcu_dereference(nf_loggers[pf]);
+		if (llog == NULL)
+			rcu_assign_pointer(nf_loggers[pf], logger);
+	}
+
 	mutex_unlock(&nf_log_mutex);
 
-	/* Give time to concurrent readers. */
-	synchronize_rcu();
+	return 0;
 }
-EXPORT_SYMBOL(nf_log_unregister_pf);
+EXPORT_SYMBOL(nf_log_register);
 
-void nf_log_unregister(const struct nf_logger *logger)
+void nf_log_unregister(struct nf_logger *logger)
 {
+	const struct nf_logger *c_logger;
 	int i;
 
 	mutex_lock(&nf_log_mutex);
 	for (i = 0; i < ARRAY_SIZE(nf_loggers); i++) {
-		if (nf_loggers[i] == logger)
+		c_logger = rcu_dereference(nf_loggers[i]);
+		if (c_logger == logger)
 			rcu_assign_pointer(nf_loggers[i], NULL);
+		list_del(&logger->list[i]);
 	}
 	mutex_unlock(&nf_log_mutex);
 
@@ -73,6 +78,27 @@ void nf_log_unregister(const struct nf_logger *logger)
 }
 EXPORT_SYMBOL(nf_log_unregister);
 
+int nf_log_bind_pf(u_int8_t pf, const struct nf_logger *logger)
+{
+	mutex_lock(&nf_log_mutex);
+	if (__find_logger(pf, logger->name) == NULL) {
+		mutex_unlock(&nf_log_mutex);
+		return -ENOENT;
+	}
+	rcu_assign_pointer(nf_loggers[pf], logger);
+	mutex_unlock(&nf_log_mutex);
+	return 0;
+}
+EXPORT_SYMBOL(nf_log_bind_pf);
+
+void nf_log_unbind_pf(u_int8_t pf)
+{
+	mutex_lock(&nf_log_mutex);
+	rcu_assign_pointer(nf_loggers[pf], NULL);
+	mutex_unlock(&nf_log_mutex);
+}
+EXPORT_SYMBOL(nf_log_unbind_pf);
+
 void nf_log_packet(u_int8_t pf,
 		   unsigned int hooknum,
 		   const struct sk_buff *skb,
@@ -129,13 +155,37 @@ static int seq_show(struct seq_file *s, void *v)
 {
 	loff_t *pos = v;
 	const struct nf_logger *logger;
+	struct nf_logger *t;
+	int ret;
 
 	logger = rcu_dereference(nf_loggers[*pos]);
 
 	if (!logger)
-		return seq_printf(s, "%2lld NONE\n", *pos);
+		ret = seq_printf(s, "%2lld NONE (", *pos);
+	else
+		ret = seq_printf(s, "%2lld %s (", *pos, logger->name);
+
+	if (ret < 0)
+		return ret;
+
+	mutex_lock(&nf_log_mutex);
+	list_for_each_entry(t, &nf_loggers_l[*pos], list[*pos]) {
+		ret = seq_printf(s, "%s", t->name);
+		if (ret < 0) {
+			mutex_unlock(&nf_log_mutex);
+			return ret;
+		}
+		if (&t->list[*pos] != nf_loggers_l[*pos].prev) {
+			ret = seq_printf(s, ",");
+			if (ret < 0) {
+				mutex_unlock(&nf_log_mutex);
+				return ret;
+			}
+		}
+	}
+	mutex_unlock(&nf_log_mutex);
 
-	return seq_printf(s, "%2lld %s\n", *pos, logger->name);
+	return seq_printf(s, ")\n");
 }
 
 static const struct seq_operations nflog_seq_ops = {
@@ -158,15 +208,102 @@ static const struct file_operations nflog_file_ops = {
 	.release = seq_release,
 };
 
+
 #endif /* PROC_FS */
 
+#ifdef CONFIG_SYSCTL
+struct ctl_path nf_log_sysctl_path[] = {
+	{ .procname = "net", .ctl_name = CTL_NET, },
+	{ .procname = "netfilter", .ctl_name = NET_NETFILTER, },
+	{ .procname = "nf_log", .ctl_name = CTL_UNNUMBERED, },
+	{ }
+};
+
+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_dir_header;
+
+static int nf_log_proc_dostring(ctl_table *table, int write, struct file *filp,
+			 void *buffer, size_t *lenp, loff_t *ppos)
+{
+	const struct nf_logger *logger;
+	int r = 0;
+	int tindex = (unsigned long)table->extra1;
+
+	if (write) {
+		if (!strcmp(buffer, "NONE")) {
+			nf_log_unbind_pf(tindex);
+			return 0;
+		}
+		mutex_lock(&nf_log_mutex);
+		logger = __find_logger(tindex, buffer);
+		if (logger == NULL) {
+			mutex_unlock(&nf_log_mutex);
+			return -ENOENT;
+		}
+		rcu_assign_pointer(nf_loggers[tindex], logger);
+		mutex_unlock(&nf_log_mutex);
+	} else {
+		rcu_read_lock();
+		logger = rcu_dereference(nf_loggers[tindex]);
+		if (!logger)
+			table->data = "NONE";
+		else
+			table->data = logger->name;
+		r = proc_dostring(table, write, filp, buffer, lenp, ppos);
+		rcu_read_unlock();
+	}
+
+	return r;
+}
+
+static __init int netfilter_log_sysctl_init(void)
+{
+	int i;
+
+	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
+		snprintf(nf_log_sysctl_fnames[i-NFPROTO_UNSPEC], 3, "%d", i);
+		nf_log_sysctl_table[i].ctl_name	= CTL_UNNUMBERED;
+		nf_log_sysctl_table[i].procname	=
+			nf_log_sysctl_fnames[i-NFPROTO_UNSPEC];
+		nf_log_sysctl_table[i].data = NULL;
+		nf_log_sysctl_table[i].maxlen =
+			NFLOGGER_NAME_LEN * sizeof(char);
+		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_dir_header = register_sysctl_paths(nf_log_sysctl_path,
+				       nf_log_sysctl_table);
+	if (!nf_log_dir_header)
+		return -ENOMEM;
+
+	return 0;
+}
+#else
+static __init int netfilter_log_sysctl_init(void)
+{
+	return 0;
+}
+#endif /* CONFIG_SYSCTL */
 
 int __init netfilter_log_init(void)
 {
+	int i, r;
 #ifdef CONFIG_PROC_FS
 	if (!proc_create("nf_log", S_IRUGO,
 			 proc_net_netfilter, &nflog_file_ops))
 		return -1;
 #endif
+
+	/* Errors will trigger panic, unroll on error is unnecessary. */
+	r = netfilter_log_sysctl_init();
+	if (r < 0)
+		return r;
+
+	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
+		INIT_LIST_HEAD(&(nf_loggers_l[i]));
+
 	return 0;
 }