lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Fri, 18 Jul 2014 13:00:59 +0200
From:	Pablo Neira Ayuso <pablo@...filter.org>
To:	netfilter-devel@...r.kernel.org
Cc:	davem@...emloft.net, netdev@...r.kernel.org
Subject: [PATCH 05/18] netfilter: nf_log: use an array of loggers instead of list

Now that legacy ulog targets are not available anymore in the tree, we
can have up to two possible loggers:

1) The plain text logging via kernel logging ring.
2) The nfnetlink_log infrastructure which delivers log messages
   to userspace.

This patch replaces the list of loggers by an array of two pointers
per family for each possible logger and it also introduces a new field
to the nf_logger structure which indicates the position in the logger
array (based on the logger type).

This prepares a follow up patch that consolidates the nf_log_packet()
interface by allowing to specify the logger as parameter.

Signed-off-by: Pablo Neira Ayuso <pablo@...filter.org>
---
 include/net/netfilter/nf_log.h |   15 +++++++-----
 net/bridge/netfilter/ebt_log.c |    1 +
 net/netfilter/nf_log.c         |   50 +++++++++++++++++++---------------------
 net/netfilter/nfnetlink_log.c  |    1 +
 net/netfilter/xt_LOG.c         |    2 ++
 5 files changed, 37 insertions(+), 32 deletions(-)

diff --git a/include/net/netfilter/nf_log.h b/include/net/netfilter/nf_log.h
index 99eac12..06b4c6b 100644
--- a/include/net/netfilter/nf_log.h
+++ b/include/net/netfilter/nf_log.h
@@ -12,8 +12,11 @@
 #define NF_LOG_UID		0x08	/* Log UID owning local socket */
 #define NF_LOG_MASK		0x0f
 
-#define NF_LOG_TYPE_LOG		0x01
-#define NF_LOG_TYPE_ULOG	0x02
+enum nf_log_type {
+	NF_LOG_TYPE_LOG		= 0,
+	NF_LOG_TYPE_ULOG,
+	NF_LOG_TYPE_MAX
+};
 
 struct nf_loginfo {
 	u_int8_t type;
@@ -40,10 +43,10 @@ typedef void nf_logfn(struct net *net,
 		      const char *prefix);
 
 struct nf_logger {
-	struct module	*me;
-	nf_logfn 	*logfn;
-	char		*name;
-	struct list_head	list[NFPROTO_NUMPROTO];
+	char			*name;
+	enum nf_log_type	type;
+	nf_logfn 		*logfn;
+	struct module		*me;
 };
 
 /* Function to register/unregister log function. */
diff --git a/net/bridge/netfilter/ebt_log.c b/net/bridge/netfilter/ebt_log.c
index 5322a36..0577477 100644
--- a/net/bridge/netfilter/ebt_log.c
+++ b/net/bridge/netfilter/ebt_log.c
@@ -207,6 +207,7 @@ static struct xt_target ebt_log_tg_reg __read_mostly = {
 
 static struct nf_logger ebt_log_logger __read_mostly = {
 	.name 		= "ebt_log",
+	.type		= NF_LOG_TYPE_LOG,
 	.logfn		= &ebt_log_packet,
 	.me		= THIS_MODULE,
 };
diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index 85296d4..7a29a3a 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -16,16 +16,22 @@
 #define NF_LOG_PREFIXLEN		128
 #define NFLOGGER_NAME_LEN		64
 
-static struct list_head nf_loggers_l[NFPROTO_NUMPROTO] __read_mostly;
+static struct nf_logger __rcu *loggers[NFPROTO_NUMPROTO][NF_LOG_TYPE_MAX] __read_mostly;
 static DEFINE_MUTEX(nf_log_mutex);
 
 static struct nf_logger *__find_logger(int pf, const char *str_logger)
 {
-	struct nf_logger *t;
+	struct nf_logger *log;
+	int i;
+
+	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
+		if (loggers[pf][i] == NULL)
+			continue;
 
-	list_for_each_entry(t, &nf_loggers_l[pf], list[pf]) {
-		if (!strnicmp(str_logger, t->name, strlen(t->name)))
-			return t;
+		log = rcu_dereference_protected(loggers[pf][i],
+						lockdep_is_held(&nf_log_mutex));
+		if (!strnicmp(str_logger, log->name, strlen(log->name)))
+			return log;
 	}
 
 	return NULL;
@@ -73,17 +79,14 @@ int nf_log_register(u_int8_t pf, struct nf_logger *logger)
 	if (pf >= ARRAY_SIZE(init_net.nf.nf_loggers))
 		return -EINVAL;
 
-	for (i = 0; i < ARRAY_SIZE(logger->list); i++)
-		INIT_LIST_HEAD(&logger->list[i]);
-
 	mutex_lock(&nf_log_mutex);
 
 	if (pf == NFPROTO_UNSPEC) {
 		for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
-			list_add_tail(&(logger->list[i]), &(nf_loggers_l[i]));
+			rcu_assign_pointer(loggers[i][logger->type], logger);
 	} else {
 		/* register at end of list to honor first register win */
-		list_add_tail(&logger->list[pf], &nf_loggers_l[pf]);
+		rcu_assign_pointer(loggers[pf][logger->type], logger);
 	}
 
 	mutex_unlock(&nf_log_mutex);
@@ -98,7 +101,7 @@ void nf_log_unregister(struct nf_logger *logger)
 
 	mutex_lock(&nf_log_mutex);
 	for (i = 0; i < NFPROTO_NUMPROTO; i++)
-		list_del(&logger->list[i]);
+		RCU_INIT_POINTER(loggers[i][logger->type], NULL);
 	mutex_unlock(&nf_log_mutex);
 }
 EXPORT_SYMBOL(nf_log_unregister);
@@ -188,8 +191,7 @@ 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;
+	int i, ret;
 	struct net *net = seq_file_net(s);
 
 	logger = rcu_dereference_protected(net->nf.nf_loggers[*pos],
@@ -203,11 +205,16 @@ static int seq_show(struct seq_file *s, void *v)
 	if (ret < 0)
 		return ret;
 
-	list_for_each_entry(t, &nf_loggers_l[*pos], list[*pos]) {
-		ret = seq_printf(s, "%s", t->name);
+	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
+		if (loggers[*pos][i] == NULL)
+			continue;
+
+		logger = rcu_dereference_protected(loggers[*pos][i],
+					   lockdep_is_held(&nf_log_mutex));
+		ret = seq_printf(s, "%s", logger->name);
 		if (ret < 0)
 			return ret;
-		if (&t->list[*pos] != nf_loggers_l[*pos].prev) {
+		if (i == 0 && loggers[*pos][i + 1] != NULL) {
 			ret = seq_printf(s, ",");
 			if (ret < 0)
 				return ret;
@@ -389,14 +396,5 @@ static struct pernet_operations nf_log_net_ops = {
 
 int __init netfilter_log_init(void)
 {
-	int i, ret;
-
-	ret = register_pernet_subsys(&nf_log_net_ops);
-	if (ret < 0)
-		return ret;
-
-	for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
-		INIT_LIST_HEAD(&(nf_loggers_l[i]));
-
-	return 0;
+	return register_pernet_subsys(&nf_log_net_ops);
 }
diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c
index d292c8d..160bb8e 100644
--- a/net/netfilter/nfnetlink_log.c
+++ b/net/netfilter/nfnetlink_log.c
@@ -773,6 +773,7 @@ nfulnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
 
 static struct nf_logger nfulnl_logger __read_mostly = {
 	.name	= "nfnetlink_log",
+	.type	= NF_LOG_TYPE_ULOG,
 	.logfn	= &nfulnl_log_packet,
 	.me	= THIS_MODULE,
 };
diff --git a/net/netfilter/xt_LOG.c b/net/netfilter/xt_LOG.c
index 5ab2484..e668d97 100644
--- a/net/netfilter/xt_LOG.c
+++ b/net/netfilter/xt_LOG.c
@@ -896,6 +896,7 @@ static struct xt_target log_tg_regs[] __read_mostly = {
 
 static struct nf_logger ipt_log_logger __read_mostly = {
 	.name		= "ipt_LOG",
+	.type		= NF_LOG_TYPE_LOG,
 	.logfn		= &ipt_log_packet,
 	.me		= THIS_MODULE,
 };
@@ -903,6 +904,7 @@ static struct nf_logger ipt_log_logger __read_mostly = {
 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
 static struct nf_logger ip6t_log_logger __read_mostly = {
 	.name		= "ip6t_LOG",
+	.type		= NF_LOG_TYPE_LOG,
 	.logfn		= &ip6t_log_packet,
 	.me		= THIS_MODULE,
 };
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ