netfilter: Enhance the codes used to get random once

There are some codes which are used to get one random once in netfilter.
We could use net_get_random_once to simplify these codes.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Gao Feng 2016-09-18 10:52:25 +08:00 committed by Pablo Neira Ayuso
parent a20877b5ed
commit 7bdc66242d
3 changed files with 4 additions and 17 deletions

View file

@ -24,7 +24,6 @@ static DEFINE_MUTEX(xt_rateest_mutex);
#define RATEEST_HSIZE 16
static struct hlist_head rateest_hash[RATEEST_HSIZE] __read_mostly;
static unsigned int jhash_rnd __read_mostly;
static bool rnd_inited __read_mostly;
static unsigned int xt_rateest_hash(const char *name)
{
@ -99,10 +98,7 @@ static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
} cfg;
int ret;
if (unlikely(!rnd_inited)) {
get_random_bytes(&jhash_rnd, sizeof(jhash_rnd));
rnd_inited = true;
}
net_get_random_once(&jhash_rnd, sizeof(jhash_rnd));
est = xt_rateest_lookup(info->name);
if (est) {

View file

@ -366,14 +366,8 @@ static int connlimit_mt_check(const struct xt_mtchk_param *par)
unsigned int i;
int ret;
if (unlikely(!connlimit_rnd)) {
u_int32_t rand;
net_get_random_once(&connlimit_rnd, sizeof(connlimit_rnd));
do {
get_random_bytes(&rand, sizeof(rand));
} while (!rand);
cmpxchg(&connlimit_rnd, 0, rand);
}
ret = nf_ct_l3proto_try_module_get(par->family);
if (ret < 0) {
pr_info("cannot load conntrack support for "

View file

@ -110,7 +110,6 @@ static const struct file_operations recent_old_fops, recent_mt_fops;
#endif
static u_int32_t hash_rnd __read_mostly;
static bool hash_rnd_inited __read_mostly;
static inline unsigned int recent_entry_hash4(const union nf_inet_addr *addr)
{
@ -340,10 +339,8 @@ static int recent_mt_check(const struct xt_mtchk_param *par,
int ret = -EINVAL;
size_t sz;
if (unlikely(!hash_rnd_inited)) {
get_random_bytes(&hash_rnd, sizeof(hash_rnd));
hash_rnd_inited = true;
}
net_get_random_once(&hash_rnd, sizeof(hash_rnd));
if (info->check_set & ~XT_RECENT_VALID_FLAGS) {
pr_info("Unsupported user space flags (%08x)\n",
info->check_set);