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Diffstat (limited to 'net/netfilter/nft_numgen.c')
-rw-r--r--net/netfilter/nft_numgen.c80
1 files changed, 58 insertions, 22 deletions
diff --git a/net/netfilter/nft_numgen.c b/net/netfilter/nft_numgen.c
index 48edb9d5f012..45d3dc9e96f2 100644
--- a/net/netfilter/nft_numgen.c
+++ b/net/netfilter/nft_numgen.c
@@ -9,16 +9,15 @@
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
+#include <linux/random.h>
#include <linux/static_key.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_core.h>
-static DEFINE_PER_CPU(struct rnd_state, nft_numgen_prandom_state);
-
struct nft_ng_inc {
- enum nft_registers dreg:8;
+ u8 dreg;
u32 modulus;
- atomic_t counter;
+ atomic_t *counter;
u32 offset;
};
@@ -27,9 +26,9 @@ static u32 nft_ng_inc_gen(struct nft_ng_inc *priv)
u32 nval, oval;
do {
- oval = atomic_read(&priv->counter);
+ oval = atomic_read(priv->counter);
nval = (oval + 1 < priv->modulus) ? oval + 1 : 0;
- } while (atomic_cmpxchg(&priv->counter, oval, nval) != oval);
+ } while (atomic_cmpxchg(priv->counter, oval, nval) != oval);
return nval + priv->offset;
}
@@ -55,6 +54,7 @@ static int nft_ng_inc_init(const struct nft_ctx *ctx,
const struct nlattr * const tb[])
{
struct nft_ng_inc *priv = nft_expr_priv(expr);
+ int err;
if (tb[NFTA_NG_OFFSET])
priv->offset = ntohl(nla_get_be32(tb[NFTA_NG_OFFSET]));
@@ -66,11 +66,32 @@ static int nft_ng_inc_init(const struct nft_ctx *ctx,
if (priv->offset + priv->modulus - 1 < priv->offset)
return -EOVERFLOW;
- priv->dreg = nft_parse_register(tb[NFTA_NG_DREG]);
- atomic_set(&priv->counter, priv->modulus - 1);
+ priv->counter = kmalloc(sizeof(*priv->counter), GFP_KERNEL);
+ if (!priv->counter)
+ return -ENOMEM;
+
+ atomic_set(priv->counter, priv->modulus - 1);
- return nft_validate_register_store(ctx, priv->dreg, NULL,
- NFT_DATA_VALUE, sizeof(u32));
+ err = nft_parse_register_store(ctx, tb[NFTA_NG_DREG], &priv->dreg,
+ NULL, NFT_DATA_VALUE, sizeof(u32));
+ if (err < 0)
+ goto err;
+
+ return 0;
+err:
+ kfree(priv->counter);
+
+ return err;
+}
+
+static bool nft_ng_inc_reduce(struct nft_regs_track *track,
+ const struct nft_expr *expr)
+{
+ const struct nft_ng_inc *priv = nft_expr_priv(expr);
+
+ nft_reg_track_cancel(track, priv->dreg, NFT_REG32_SIZE);
+
+ return false;
}
static int nft_ng_dump(struct sk_buff *skb, enum nft_registers dreg,
@@ -99,18 +120,23 @@ static int nft_ng_inc_dump(struct sk_buff *skb, const struct nft_expr *expr)
priv->offset);
}
+static void nft_ng_inc_destroy(const struct nft_ctx *ctx,
+ const struct nft_expr *expr)
+{
+ const struct nft_ng_inc *priv = nft_expr_priv(expr);
+
+ kfree(priv->counter);
+}
+
struct nft_ng_random {
- enum nft_registers dreg:8;
+ u8 dreg;
u32 modulus;
u32 offset;
};
-static u32 nft_ng_random_gen(struct nft_ng_random *priv)
+static u32 nft_ng_random_gen(const struct nft_ng_random *priv)
{
- struct rnd_state *state = this_cpu_ptr(&nft_numgen_prandom_state);
-
- return reciprocal_scale(prandom_u32_state(state), priv->modulus) +
- priv->offset;
+ return reciprocal_scale(get_random_u32(), priv->modulus) + priv->offset;
}
static void nft_ng_random_eval(const struct nft_expr *expr,
@@ -138,12 +164,8 @@ static int nft_ng_random_init(const struct nft_ctx *ctx,
if (priv->offset + priv->modulus - 1 < priv->offset)
return -EOVERFLOW;
- prandom_init_once(&nft_numgen_prandom_state);
-
- priv->dreg = nft_parse_register(tb[NFTA_NG_DREG]);
-
- return nft_validate_register_store(ctx, priv->dreg, NULL,
- NFT_DATA_VALUE, sizeof(u32));
+ return nft_parse_register_store(ctx, tb[NFTA_NG_DREG], &priv->dreg,
+ NULL, NFT_DATA_VALUE, sizeof(u32));
}
static int nft_ng_random_dump(struct sk_buff *skb, const struct nft_expr *expr)
@@ -154,13 +176,25 @@ static int nft_ng_random_dump(struct sk_buff *skb, const struct nft_expr *expr)
priv->offset);
}
+static bool nft_ng_random_reduce(struct nft_regs_track *track,
+ const struct nft_expr *expr)
+{
+ const struct nft_ng_random *priv = nft_expr_priv(expr);
+
+ nft_reg_track_cancel(track, priv->dreg, NFT_REG32_SIZE);
+
+ return false;
+}
+
static struct nft_expr_type nft_ng_type;
static const struct nft_expr_ops nft_ng_inc_ops = {
.type = &nft_ng_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_ng_inc)),
.eval = nft_ng_inc_eval,
.init = nft_ng_inc_init,
+ .destroy = nft_ng_inc_destroy,
.dump = nft_ng_inc_dump,
+ .reduce = nft_ng_inc_reduce,
};
static const struct nft_expr_ops nft_ng_random_ops = {
@@ -169,6 +203,7 @@ static const struct nft_expr_ops nft_ng_random_ops = {
.eval = nft_ng_random_eval,
.init = nft_ng_random_init,
.dump = nft_ng_random_dump,
+ .reduce = nft_ng_random_reduce,
};
static const struct nft_expr_ops *
@@ -217,3 +252,4 @@ module_exit(nft_ng_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Laura Garcia <nevola@gmail.com>");
MODULE_ALIAS_NFT_EXPR("numgen");
+MODULE_DESCRIPTION("nftables number generator module");