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Release 4.11 net/netfilter/nft_limit.c

Directory: net/netfilter
/*
 * 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		last;
	
u64		tokens;
	
u64		tokens_max;
	
u64		rate;
	
u64		nsecs;
	
u32		burst;
	
bool		invert;
};


static inline bool nft_limit_eval(struct nft_limit *limit, u64 cost) { u64 now, tokens; s64 delta; spin_lock_bh(&limit_lock); now = ktime_get_ns(); tokens = limit->tokens + now - limit->last; if (tokens > limit->tokens_max) tokens = limit->tokens_max; limit->last = now; delta = tokens - cost; if (delta >= 0) { limit->tokens = delta; spin_unlock_bh(&limit_lock); return limit->invert; } limit->tokens = tokens; spin_unlock_bh(&limit_lock); return !limit->invert; }

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PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso6960.00%375.00%
Patrick McHardy4640.00%125.00%
Total115100.00%4100.00%


static int nft_limit_init(struct nft_limit *limit, const struct nlattr * const tb[]) { u64 unit; if (tb[NFTA_LIMIT_RATE] == NULL || tb[NFTA_LIMIT_UNIT] == NULL) return -EINVAL; limit->rate = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_RATE])); unit = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_UNIT])); limit->nsecs = unit * NSEC_PER_SEC; 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; } if (tb[NFTA_LIMIT_FLAGS]) { u32 flags = ntohl(nla_get_be32(tb[NFTA_LIMIT_FLAGS])); if (flags & NFT_LIMIT_F_INV) limit->invert = true; } limit->last = ktime_get_ns(); return 0; }

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PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso13162.98%480.00%
Patrick McHardy7737.02%120.00%
Total208100.00%5100.00%


static int nft_limit_dump(struct sk_buff *skb, const struct nft_limit *limit, enum nft_limit_type type) { u32 flags = limit->invert ? NFT_LIMIT_F_INV : 0; 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(rate), NFTA_LIMIT_PAD) || nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(secs), NFTA_LIMIT_PAD) || nla_put_be32(skb, NFTA_LIMIT_BURST, htonl(limit->burst)) || nla_put_be32(skb, NFTA_LIMIT_TYPE, htonl(type)) || nla_put_be32(skb, NFTA_LIMIT_FLAGS, htonl(flags))) goto nla_put_failure; return 0; nla_put_failure: return -1; }

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PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso8059.26%571.43%
Patrick McHardy5137.78%114.29%
Nicolas Dichtel42.96%114.29%
Total135100.00%7100.00%

struct nft_limit_pkts { struct nft_limit limit; u64 cost; };
static void nft_limit_pkts_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) { struct nft_limit_pkts *priv = nft_expr_priv(expr); if (nft_limit_eval(&priv->limit, priv->cost)) regs->verdict.code = NFT_BREAK; }

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Pablo Neira Ayuso55100.00%2100.00%
Total55100.00%2100.00%

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 }, [NFTA_LIMIT_TYPE] = { .type = NLA_U32 }, [NFTA_LIMIT_FLAGS] = { .type = NLA_U32 }, };
static int nft_limit_pkts_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]) { struct nft_limit_pkts *priv = nft_expr_priv(expr); int err; err = nft_limit_init(&priv->limit, tb); if (err < 0) return err; priv->cost = div64_u64(priv->limit.nsecs, priv->limit.rate); return 0; }

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PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso8198.78%266.67%
Liping Zhang11.22%133.33%
Total82100.00%3100.00%


static int nft_limit_pkts_dump(struct sk_buff *skb, const struct nft_expr *expr) { const struct nft_limit_pkts *priv = nft_expr_priv(expr); return nft_limit_dump(skb, &priv->limit, NFT_LIMIT_PKTS); }

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Pablo Neira Ayuso41100.00%3100.00%
Total41100.00%3100.00%

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_pkts)), .eval = nft_limit_pkts_eval, .init = nft_limit_pkts_init, .dump = nft_limit_pkts_dump, };
static void nft_limit_pkt_bytes_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) { struct nft_limit *priv = nft_expr_priv(expr); u64 cost = div64_u64(priv->nsecs * pkt->skb->len, priv->rate); if (nft_limit_eval(priv, cost)) regs->verdict.code = NFT_BREAK; }

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Pablo Neira Ayuso6998.57%150.00%
Liping Zhang11.43%150.00%
Total70100.00%2100.00%


static int nft_limit_pkt_bytes_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]) { struct nft_limit *priv = nft_expr_priv(expr); return nft_limit_init(priv, tb); }

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Pablo Neira Ayuso44100.00%1100.00%
Total44100.00%1100.00%


static int nft_limit_pkt_bytes_dump(struct sk_buff *skb, const struct nft_expr *expr) { const struct nft_limit *priv = nft_expr_priv(expr); return nft_limit_dump(skb, priv, NFT_LIMIT_PKT_BYTES); }

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Pablo Neira Ayuso38100.00%1100.00%
Total38100.00%1100.00%

static const struct nft_expr_ops nft_limit_pkt_bytes_ops = { .type = &nft_limit_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_limit)), .eval = nft_limit_pkt_bytes_eval, .init = nft_limit_pkt_bytes_init, .dump = nft_limit_pkt_bytes_dump, };
static const struct nft_expr_ops * nft_limit_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[]) { if (tb[NFTA_LIMIT_TYPE] == NULL) return &nft_limit_pkts_ops; switch (ntohl(nla_get_be32(tb[NFTA_LIMIT_TYPE]))) { case NFT_LIMIT_PKTS: return &nft_limit_pkts_ops; case NFT_LIMIT_PKT_BYTES: return &nft_limit_pkt_bytes_ops; } return ERR_PTR(-EOPNOTSUPP); }

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Pablo Neira Ayuso72100.00%1100.00%
Total72100.00%1100.00%

static struct nft_expr_type nft_limit_type __read_mostly = { .name = "limit", .select_ops = nft_limit_select_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); }

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Patrick McHardy16100.00%2100.00%
Total16100.00%2100.00%


static void __exit nft_limit_module_exit(void) { nft_unregister_expr(&nft_limit_type); }

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Patrick McHardy15100.00%2100.00%
Total15100.00%2100.00%

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");

Overall Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso82169.69%758.33%
Patrick McHardy35129.80%325.00%
Nicolas Dichtel40.34%18.33%
Liping Zhang20.17%18.33%
Total1178100.00%12100.00%
Directory: net/netfilter
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