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authorLaura Garcia Liebana <nevola@gmail.com>2018-05-11 00:14:17 +0200
committerPablo Neira Ayuso <pablo@netfilter.org>2018-05-17 14:00:41 +0200
commit978d8f9055c3a7c35db2ac99cd2580b993396e33 (patch)
tree30450476639cacdc078c6923be317135dd0808b1 /net/netfilter/nft_numgen.c
parente65eebec9c67dfd973d8b79844b992ff828d00df (diff)
netfilter: nft_numgen: add map lookups for numgen random operations
This patch uses the map lookup already included to be applied for random number generation. Signed-off-by: Laura Garcia Liebana <nevola@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nft_numgen.c')
-rw-r--r--net/netfilter/nft_numgen.c76
1 files changed, 72 insertions, 4 deletions
diff --git a/net/netfilter/nft_numgen.c b/net/netfilter/nft_numgen.c
index 8a64db8f2e69..cdbc62a53933 100644
--- a/net/netfilter/nft_numgen.c
+++ b/net/netfilter/nft_numgen.c
@@ -166,18 +166,43 @@ struct nft_ng_random {
enum nft_registers dreg:8;
u32 modulus;
u32 offset;
+ struct nft_set *map;
};
+static u32 nft_ng_random_gen(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;
+}
+
static void nft_ng_random_eval(const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
struct nft_ng_random *priv = nft_expr_priv(expr);
- struct rnd_state *state = this_cpu_ptr(&nft_numgen_prandom_state);
- u32 val;
- val = reciprocal_scale(prandom_u32_state(state), priv->modulus);
- regs->data[priv->dreg] = val + priv->offset;
+ regs->data[priv->dreg] = nft_ng_random_gen(priv);
+}
+
+static void nft_ng_random_map_eval(const struct nft_expr *expr,
+ struct nft_regs *regs,
+ const struct nft_pktinfo *pkt)
+{
+ struct nft_ng_random *priv = nft_expr_priv(expr);
+ const struct nft_set *map = priv->map;
+ const struct nft_set_ext *ext;
+ u32 result;
+ bool found;
+
+ result = nft_ng_random_gen(priv);
+ found = map->ops->lookup(nft_net(pkt), map, &result, &ext);
+ if (!found)
+ return;
+
+ nft_data_copy(&regs->data[priv->dreg],
+ nft_set_ext_data(ext), map->dlen);
}
static int nft_ng_random_init(const struct nft_ctx *ctx,
@@ -204,6 +229,23 @@ static int nft_ng_random_init(const struct nft_ctx *ctx,
NFT_DATA_VALUE, sizeof(u32));
}
+static int nft_ng_random_map_init(const struct nft_ctx *ctx,
+ const struct nft_expr *expr,
+ const struct nlattr * const tb[])
+{
+ struct nft_ng_random *priv = nft_expr_priv(expr);
+ u8 genmask = nft_genmask_next(ctx->net);
+
+ nft_ng_random_init(ctx, expr, tb);
+ priv->map = nft_set_lookup_global(ctx->net, ctx->table,
+ tb[NFTA_NG_SET_NAME],
+ tb[NFTA_NG_SET_ID], genmask);
+ if (IS_ERR(priv->map))
+ return PTR_ERR(priv->map);
+
+ return 0;
+}
+
static int nft_ng_random_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
const struct nft_ng_random *priv = nft_expr_priv(expr);
@@ -212,6 +254,22 @@ static int nft_ng_random_dump(struct sk_buff *skb, const struct nft_expr *expr)
priv->offset);
}
+static int nft_ng_random_map_dump(struct sk_buff *skb,
+ const struct nft_expr *expr)
+{
+ const struct nft_ng_random *priv = nft_expr_priv(expr);
+
+ if (nft_ng_dump(skb, priv->dreg, priv->modulus,
+ NFT_NG_RANDOM, priv->offset) ||
+ nla_put_string(skb, NFTA_NG_SET_NAME, priv->map->name))
+ goto nla_put_failure;
+
+ return 0;
+
+nla_put_failure:
+ return -1;
+}
+
static struct nft_expr_type nft_ng_type;
static const struct nft_expr_ops nft_ng_inc_ops = {
.type = &nft_ng_type,
@@ -237,6 +295,14 @@ static const struct nft_expr_ops nft_ng_random_ops = {
.dump = nft_ng_random_dump,
};
+static const struct nft_expr_ops nft_ng_random_map_ops = {
+ .type = &nft_ng_type,
+ .size = NFT_EXPR_SIZE(sizeof(struct nft_ng_random)),
+ .eval = nft_ng_random_map_eval,
+ .init = nft_ng_random_map_init,
+ .dump = nft_ng_random_map_dump,
+};
+
static const struct nft_expr_ops *
nft_ng_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[])
{
@@ -255,6 +321,8 @@ nft_ng_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[])
return &nft_ng_inc_map_ops;
return &nft_ng_inc_ops;
case NFT_NG_RANDOM:
+ if (tb[NFTA_NG_SET_NAME])
+ return &nft_ng_random_map_ops;
return &nft_ng_random_ops;
}