netfilter: nft_limit: move stateful fields out of expression data

In preparation for the rule blob representation.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nft_limit.c b/net/netfilter/nft_limit.c
index d6e0226..f04be5b 100644 (file)
--- a/net/netfilter/nft_limit.c
+++ b/net/netfilter/nft_limit.c
@@ -14,10 +14,14 @@
 #include <linux/netfilter/nf_tables.h>
 #include <net/netfilter/nf_tables.h>
 
-struct nft_limit_priv {
+struct nft_limit {
        spinlock_t      lock;
        u64             last;
        u64             tokens;
+};
+
+struct nft_limit_priv {
+       struct nft_limit *limit;
        u64             tokens_max;
        u64             rate;
        u64             nsecs;
@@ -30,21 +34,21 @@ static inline bool nft_limit_eval(struct nft_limit_priv *priv, u64 cost)
        u64 now, tokens;
        s64 delta;
 
-       spin_lock_bh(&priv->lock);
+       spin_lock_bh(&priv->limit->lock);
        now = ktime_get_ns();
-       tokens = priv->tokens + now - priv->last;
+       tokens = priv->limit->tokens + now - priv->limit->last;
        if (tokens > priv->tokens_max)
                tokens = priv->tokens_max;
 
-       priv->last = now;
+       priv->limit->last = now;
        delta = tokens - cost;
        if (delta >= 0) {
-               priv->tokens = delta;
-               spin_unlock_bh(&priv->lock);
+               priv->limit->tokens = delta;
+               spin_unlock_bh(&priv->limit->lock);
                return priv->invert;
        }
-       priv->tokens = tokens;
-       spin_unlock_bh(&priv->lock);
+       priv->limit->tokens = tokens;
+       spin_unlock_bh(&priv->limit->lock);
        return !priv->invert;
 }
 
@@ -86,8 +90,12 @@ static int nft_limit_init(struct nft_limit_priv *priv,
                                 priv->rate);
        }
 
-       priv->tokens = tokens;
-       priv->tokens_max = priv->tokens;
+       priv->limit = kmalloc(sizeof(*priv->limit), GFP_KERNEL);
+       if (!priv->limit)
+               return -ENOMEM;
+
+       priv->limit->tokens = tokens;
+       priv->tokens_max = priv->limit->tokens;
 
        if (tb[NFTA_LIMIT_FLAGS]) {
                u32 flags = ntohl(nla_get_be32(tb[NFTA_LIMIT_FLAGS]));
@@ -95,8 +103,8 @@ static int nft_limit_init(struct nft_limit_priv *priv,
                if (flags & NFT_LIMIT_F_INV)
                        priv->invert = true;
        }
-       priv->last = ktime_get_ns();
-       spin_lock_init(&priv->lock);
+       priv->limit->last = ktime_get_ns();
+       spin_lock_init(&priv->limit->lock);
 
        return 0;
 }
@@ -121,6 +129,32 @@ nla_put_failure:
        return -1;
 }
 
+static void nft_limit_destroy(const struct nft_ctx *ctx,
+                             const struct nft_limit_priv *priv)
+{
+       kfree(priv->limit);
+}
+
+static int nft_limit_clone(struct nft_limit_priv *priv_dst,
+                          const struct nft_limit_priv *priv_src)
+{
+       priv_dst->tokens_max = priv_src->tokens_max;
+       priv_dst->rate = priv_src->rate;
+       priv_dst->nsecs = priv_src->nsecs;
+       priv_dst->burst = priv_src->burst;
+       priv_dst->invert = priv_src->invert;
+
+       priv_dst->limit = kmalloc(sizeof(*priv_dst->limit), GFP_ATOMIC);
+       if (priv_dst->limit)
+               return -ENOMEM;
+
+       spin_lock_init(&priv_dst->limit->lock);
+       priv_dst->limit->tokens = priv_src->tokens_max;
+       priv_dst->limit->last = ktime_get_ns();
+
+       return 0;
+}
+
 struct nft_limit_priv_pkts {
        struct nft_limit_priv   limit;
        u64                     cost;
@@ -166,12 +200,30 @@ static int nft_limit_pkts_dump(struct sk_buff *skb, const struct nft_expr *expr)
        return nft_limit_dump(skb, &priv->limit, NFT_LIMIT_PKTS);
 }
 
+static void nft_limit_pkts_destroy(const struct nft_ctx *ctx,
+                                  const struct nft_expr *expr)
+{
+       const struct nft_limit_priv_pkts *priv = nft_expr_priv(expr);
+
+       nft_limit_destroy(ctx, &priv->limit);
+}
+
+static int nft_limit_pkts_clone(struct nft_expr *dst, const struct nft_expr *src)
+{
+       struct nft_limit_priv_pkts *priv_dst = nft_expr_priv(dst);
+       struct nft_limit_priv_pkts *priv_src = nft_expr_priv(src);
+
+       return nft_limit_clone(&priv_dst->limit, &priv_src->limit);
+}
+
 static struct nft_expr_type nft_limit_type;
 static const struct nft_expr_ops nft_limit_pkts_ops = {
        .type           = &nft_limit_type,
        .size           = NFT_EXPR_SIZE(sizeof(struct nft_limit_priv_pkts)),
        .eval           = nft_limit_pkts_eval,
        .init           = nft_limit_pkts_init,
+       .destroy        = nft_limit_pkts_destroy,
+       .clone          = nft_limit_pkts_clone,
        .dump           = nft_limit_pkts_dump,
 };
 
@@ -203,12 +255,30 @@ static int nft_limit_bytes_dump(struct sk_buff *skb,
        return nft_limit_dump(skb, priv, NFT_LIMIT_PKT_BYTES);
 }
 
+static void nft_limit_bytes_destroy(const struct nft_ctx *ctx,
+                                   const struct nft_expr *expr)
+{
+       const struct nft_limit_priv *priv = nft_expr_priv(expr);
+
+       nft_limit_destroy(ctx, priv);
+}
+
+static int nft_limit_bytes_clone(struct nft_expr *dst, const struct nft_expr *src)
+{
+       struct nft_limit_priv *priv_dst = nft_expr_priv(dst);
+       struct nft_limit_priv *priv_src = nft_expr_priv(src);
+
+       return nft_limit_clone(priv_dst, priv_src);
+}
+
 static const struct nft_expr_ops nft_limit_bytes_ops = {
        .type           = &nft_limit_type,
        .size           = NFT_EXPR_SIZE(sizeof(struct nft_limit_priv)),
        .eval           = nft_limit_bytes_eval,
        .init           = nft_limit_bytes_init,
        .dump           = nft_limit_bytes_dump,
+       .clone          = nft_limit_bytes_clone,
+       .destroy        = nft_limit_bytes_destroy,
 };
 
 static const struct nft_expr_ops *