Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / net / netfilter / nft_limit.c

diff --git a/kernel/net/netfilter/nft_limit.c b/kernel/net/netfilter/nft_limit.c
new file mode 100644 (file)
index 0000000..435c1cc
--- /dev/null
+++ b/kernel/net/netfilter/nft_limit.c
@@ -0,0 +1,120 @@
+/*
+ * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Development of this code funded by Astaro AG (http://www.astaro.com/)
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/netlink.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/nf_tables.h>
+#include <net/netfilter/nf_tables.h>
+
+static DEFINE_SPINLOCK(limit_lock);
+
+struct nft_limit {
+       u64             tokens;
+       u64             rate;
+       u64             unit;
+       unsigned long   stamp;
+};
+
+static void nft_limit_eval(const struct nft_expr *expr,
+                          struct nft_regs *regs,
+                          const struct nft_pktinfo *pkt)
+{
+       struct nft_limit *priv = nft_expr_priv(expr);
+
+       spin_lock_bh(&limit_lock);
+       if (time_after_eq(jiffies, priv->stamp)) {
+               priv->tokens = priv->rate;
+               priv->stamp = jiffies + priv->unit * HZ;
+       }
+
+       if (priv->tokens >= 1) {
+               priv->tokens--;
+               spin_unlock_bh(&limit_lock);
+               return;
+       }
+       spin_unlock_bh(&limit_lock);
+
+       regs->verdict.code = NFT_BREAK;
+}
+
+static const struct nla_policy nft_limit_policy[NFTA_LIMIT_MAX + 1] = {
+       [NFTA_LIMIT_RATE]       = { .type = NLA_U64 },
+       [NFTA_LIMIT_UNIT]       = { .type = NLA_U64 },
+};
+
+static int nft_limit_init(const struct nft_ctx *ctx,
+                         const struct nft_expr *expr,
+                         const struct nlattr * const tb[])
+{
+       struct nft_limit *priv = nft_expr_priv(expr);
+
+       if (tb[NFTA_LIMIT_RATE] == NULL ||
+           tb[NFTA_LIMIT_UNIT] == NULL)
+               return -EINVAL;
+
+       priv->rate   = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_RATE]));
+       priv->unit   = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_UNIT]));
+       priv->stamp  = jiffies + priv->unit * HZ;
+       priv->tokens = priv->rate;
+       return 0;
+}
+
+static int nft_limit_dump(struct sk_buff *skb, const struct nft_expr *expr)
+{
+       const struct nft_limit *priv = nft_expr_priv(expr);
+
+       if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(priv->rate)))
+               goto nla_put_failure;
+       if (nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(priv->unit)))
+               goto nla_put_failure;
+       return 0;
+
+nla_put_failure:
+       return -1;
+}
+
+static struct nft_expr_type nft_limit_type;
+static const struct nft_expr_ops nft_limit_ops = {
+       .type           = &nft_limit_type,
+       .size           = NFT_EXPR_SIZE(sizeof(struct nft_limit)),
+       .eval           = nft_limit_eval,
+       .init           = nft_limit_init,
+       .dump           = nft_limit_dump,
+};
+
+static struct nft_expr_type nft_limit_type __read_mostly = {
+       .name           = "limit",
+       .ops            = &nft_limit_ops,
+       .policy         = nft_limit_policy,
+       .maxattr        = NFTA_LIMIT_MAX,
+       .flags          = NFT_EXPR_STATEFUL,
+       .owner          = THIS_MODULE,
+};
+
+static int __init nft_limit_module_init(void)
+{
+       return nft_register_expr(&nft_limit_type);
+}
+
+static void __exit nft_limit_module_exit(void)
+{
+       nft_unregister_expr(&nft_limit_type);
+}
+
+module_init(nft_limit_module_init);
+module_exit(nft_limit_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_ALIAS_NFT_EXPR("limit");