From 3e87baafa4f476017b2453e52a1ca7308b4e6ad5 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Sun, 2 Aug 2015 18:02:14 +0200 Subject: [PATCH] netfilter: nft_limit: add burst parameter This patch adds the burst parameter. This burst indicates the number of packets that can exceed the limit. Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_tables.h | 2 ++ net/netfilter/nft_limit.c | 20 ++++++++++++++++++-- 2 files changed, 20 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 2ef35f2c9bda..cafd78943c7d 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -761,11 +761,13 @@ enum nft_ct_attributes { * * @NFTA_LIMIT_RATE: refill rate (NLA_U64) * @NFTA_LIMIT_UNIT: refill unit (NLA_U64) + * @NFTA_LIMIT_BURST: burst (NLA_U32) */ enum nft_limit_attributes { NFTA_LIMIT_UNSPEC, NFTA_LIMIT_RATE, NFTA_LIMIT_UNIT, + NFTA_LIMIT_BURST, __NFTA_LIMIT_MAX }; #define NFTA_LIMIT_MAX (__NFTA_LIMIT_MAX - 1) diff --git a/net/netfilter/nft_limit.c b/net/netfilter/nft_limit.c index c4d1b1b75b8f..d8c5ff1bf7dd 100644 --- a/net/netfilter/nft_limit.c +++ b/net/netfilter/nft_limit.c @@ -25,6 +25,7 @@ struct nft_limit { u64 tokens_max; u64 rate; u64 nsecs; + u32 burst; }; static inline bool nft_limit_eval(struct nft_limit *limit, u64 cost) @@ -65,6 +66,18 @@ static int nft_limit_init(struct nft_limit *limit, if (limit->rate == 0 || limit->nsecs < unit) return -EOVERFLOW; limit->tokens = limit->tokens_max = limit->nsecs; + + if (tb[NFTA_LIMIT_BURST]) { + u64 rate; + + limit->burst = ntohl(nla_get_be32(tb[NFTA_LIMIT_BURST])); + + rate = limit->rate + limit->burst; + if (rate < limit->rate) + return -EOVERFLOW; + + limit->rate = rate; + } limit->last = ktime_get_ns(); return 0; @@ -73,9 +86,11 @@ static int nft_limit_init(struct nft_limit *limit, static int nft_limit_dump(struct sk_buff *skb, const struct nft_limit *limit) { u64 secs = div_u64(limit->nsecs, NSEC_PER_SEC); + u64 rate = limit->rate - limit->burst; - if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(limit->rate)) || - nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(secs))) + if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(rate)) || + nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(secs)) || + nla_put_be32(skb, NFTA_LIMIT_BURST, htonl(limit->burst))) goto nla_put_failure; return 0; @@ -96,6 +111,7 @@ static void nft_limit_pkts_eval(const struct nft_expr *expr, static const struct nla_policy nft_limit_policy[NFTA_LIMIT_MAX + 1] = { [NFTA_LIMIT_RATE] = { .type = NLA_U64 }, [NFTA_LIMIT_UNIT] = { .type = NLA_U64 }, + [NFTA_LIMIT_BURST] = { .type = NLA_U32 }, }; static int nft_limit_pkts_init(const struct nft_ctx *ctx, -- 2.34.1