1 /* 2 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * Development of this code funded by Astaro AG (http://www.astaro.com/) 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/init.h> 13 #include <linux/module.h> 14 #include <linux/seqlock.h> 15 #include <linux/netlink.h> 16 #include <linux/netfilter.h> 17 #include <linux/netfilter/nf_tables.h> 18 #include <net/netfilter/nf_tables.h> 19 20 struct nft_counter { 21 seqlock_t lock; 22 u64 bytes; 23 u64 packets; 24 }; 25 26 static void nft_counter_eval(const struct nft_expr *expr, 27 struct nft_regs *regs, 28 const struct nft_pktinfo *pkt) 29 { 30 struct nft_counter *priv = nft_expr_priv(expr); 31 32 write_seqlock_bh(&priv->lock); 33 priv->bytes += pkt->skb->len; 34 priv->packets++; 35 write_sequnlock_bh(&priv->lock); 36 } 37 38 static int nft_counter_dump(struct sk_buff *skb, const struct nft_expr *expr) 39 { 40 struct nft_counter *priv = nft_expr_priv(expr); 41 unsigned int seq; 42 u64 bytes; 43 u64 packets; 44 45 do { 46 seq = read_seqbegin(&priv->lock); 47 bytes = priv->bytes; 48 packets = priv->packets; 49 } while (read_seqretry(&priv->lock, seq)); 50 51 if (nla_put_be64(skb, NFTA_COUNTER_BYTES, cpu_to_be64(bytes))) 52 goto nla_put_failure; 53 if (nla_put_be64(skb, NFTA_COUNTER_PACKETS, cpu_to_be64(packets))) 54 goto nla_put_failure; 55 return 0; 56 57 nla_put_failure: 58 return -1; 59 } 60 61 static const struct nla_policy nft_counter_policy[NFTA_COUNTER_MAX + 1] = { 62 [NFTA_COUNTER_PACKETS] = { .type = NLA_U64 }, 63 [NFTA_COUNTER_BYTES] = { .type = NLA_U64 }, 64 }; 65 66 static int nft_counter_init(const struct nft_ctx *ctx, 67 const struct nft_expr *expr, 68 const struct nlattr * const tb[]) 69 { 70 struct nft_counter *priv = nft_expr_priv(expr); 71 72 if (tb[NFTA_COUNTER_PACKETS]) 73 priv->packets = be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_PACKETS])); 74 if (tb[NFTA_COUNTER_BYTES]) 75 priv->bytes = be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_BYTES])); 76 77 seqlock_init(&priv->lock); 78 return 0; 79 } 80 81 static struct nft_expr_type nft_counter_type; 82 static const struct nft_expr_ops nft_counter_ops = { 83 .type = &nft_counter_type, 84 .size = NFT_EXPR_SIZE(sizeof(struct nft_counter)), 85 .eval = nft_counter_eval, 86 .init = nft_counter_init, 87 .dump = nft_counter_dump, 88 }; 89 90 static struct nft_expr_type nft_counter_type __read_mostly = { 91 .name = "counter", 92 .ops = &nft_counter_ops, 93 .policy = nft_counter_policy, 94 .maxattr = NFTA_COUNTER_MAX, 95 .flags = NFT_EXPR_STATEFUL, 96 .owner = THIS_MODULE, 97 }; 98 99 static int __init nft_counter_module_init(void) 100 { 101 return nft_register_expr(&nft_counter_type); 102 } 103 104 static void __exit nft_counter_module_exit(void) 105 { 106 nft_unregister_expr(&nft_counter_type); 107 } 108 109 module_init(nft_counter_module_init); 110 module_exit(nft_counter_module_exit); 111 112 MODULE_LICENSE("GPL"); 113 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); 114 MODULE_ALIAS_NFT_EXPR("counter"); 115