Patrick McHardy | 50c164a | 2007-12-04 13:02:19 +0100 | [diff] [blame] | 1 | /* |
| 2 | * (C) 2007 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 | #include <linux/module.h> |
| 9 | #include <linux/skbuff.h> |
| 10 | #include <linux/gen_stats.h> |
| 11 | |
| 12 | #include <linux/netfilter/x_tables.h> |
| 13 | #include <linux/netfilter/xt_rateest.h> |
| 14 | #include <net/netfilter/xt_rateest.h> |
| 15 | |
| 16 | |
| 17 | static bool xt_rateest_mt(const struct sk_buff *skb, |
| 18 | const struct net_device *in, |
| 19 | const struct net_device *out, |
| 20 | const struct xt_match *match, |
| 21 | const void *matchinfo, |
| 22 | int offset, |
| 23 | unsigned int protoff, |
| 24 | bool *hotdrop) |
| 25 | { |
| 26 | const struct xt_rateest_match_info *info = matchinfo; |
| 27 | struct gnet_stats_rate_est *r; |
| 28 | u_int32_t bps1, bps2, pps1, pps2; |
| 29 | bool ret = true; |
| 30 | |
| 31 | spin_lock_bh(&info->est1->lock); |
| 32 | r = &info->est1->rstats; |
| 33 | if (info->flags & XT_RATEEST_MATCH_DELTA) { |
| 34 | bps1 = info->bps1 >= r->bps ? info->bps1 - r->bps : 0; |
| 35 | pps1 = info->pps1 >= r->pps ? info->pps1 - r->pps : 0; |
| 36 | } else { |
| 37 | bps1 = r->bps; |
| 38 | pps1 = r->pps; |
| 39 | } |
| 40 | spin_unlock_bh(&info->est1->lock); |
| 41 | |
| 42 | if (info->flags & XT_RATEEST_MATCH_ABS) { |
| 43 | bps2 = info->bps2; |
| 44 | pps2 = info->pps2; |
| 45 | } else { |
| 46 | spin_lock_bh(&info->est2->lock); |
| 47 | r = &info->est2->rstats; |
| 48 | if (info->flags & XT_RATEEST_MATCH_DELTA) { |
| 49 | bps2 = info->bps2 >= r->bps ? info->bps2 - r->bps : 0; |
| 50 | pps2 = info->pps2 >= r->pps ? info->pps2 - r->pps : 0; |
| 51 | } else { |
| 52 | bps2 = r->bps; |
| 53 | pps2 = r->pps; |
| 54 | } |
| 55 | spin_unlock_bh(&info->est2->lock); |
| 56 | } |
| 57 | |
| 58 | switch (info->mode) { |
| 59 | case XT_RATEEST_MATCH_LT: |
| 60 | if (info->flags & XT_RATEEST_MATCH_BPS) |
| 61 | ret &= bps1 < bps2; |
| 62 | if (info->flags & XT_RATEEST_MATCH_PPS) |
| 63 | ret &= pps1 < pps2; |
| 64 | break; |
| 65 | case XT_RATEEST_MATCH_GT: |
| 66 | if (info->flags & XT_RATEEST_MATCH_BPS) |
| 67 | ret &= bps1 > bps2; |
| 68 | if (info->flags & XT_RATEEST_MATCH_PPS) |
| 69 | ret &= pps1 > pps2; |
| 70 | break; |
| 71 | case XT_RATEEST_MATCH_EQ: |
| 72 | if (info->flags & XT_RATEEST_MATCH_BPS) |
| 73 | ret &= bps1 == bps2; |
| 74 | if (info->flags & XT_RATEEST_MATCH_PPS) |
| 75 | ret &= pps2 == pps2; |
| 76 | break; |
| 77 | } |
| 78 | |
| 79 | ret ^= info->flags & XT_RATEEST_MATCH_INVERT ? true : false; |
| 80 | return ret; |
| 81 | } |
| 82 | |
| 83 | static bool xt_rateest_mt_checkentry(const char *tablename, |
| 84 | const void *ip, |
| 85 | const struct xt_match *match, |
| 86 | void *matchinfo, |
| 87 | unsigned int hook_mask) |
| 88 | { |
Jan Engelhardt | 3cf93c9 | 2008-04-14 09:56:05 +0200 | [diff] [blame] | 89 | struct xt_rateest_match_info *info = matchinfo; |
Patrick McHardy | 50c164a | 2007-12-04 13:02:19 +0100 | [diff] [blame] | 90 | struct xt_rateest *est1, *est2; |
| 91 | |
| 92 | if (hweight32(info->flags & (XT_RATEEST_MATCH_ABS | |
| 93 | XT_RATEEST_MATCH_REL)) != 1) |
| 94 | goto err1; |
| 95 | |
| 96 | if (!(info->flags & (XT_RATEEST_MATCH_BPS | XT_RATEEST_MATCH_PPS))) |
| 97 | goto err1; |
| 98 | |
| 99 | switch (info->mode) { |
| 100 | case XT_RATEEST_MATCH_EQ: |
| 101 | case XT_RATEEST_MATCH_LT: |
| 102 | case XT_RATEEST_MATCH_GT: |
| 103 | break; |
| 104 | default: |
| 105 | goto err1; |
| 106 | } |
| 107 | |
| 108 | est1 = xt_rateest_lookup(info->name1); |
| 109 | if (!est1) |
| 110 | goto err1; |
| 111 | |
| 112 | if (info->flags & XT_RATEEST_MATCH_REL) { |
| 113 | est2 = xt_rateest_lookup(info->name2); |
| 114 | if (!est2) |
| 115 | goto err2; |
| 116 | } else |
| 117 | est2 = NULL; |
| 118 | |
| 119 | |
| 120 | info->est1 = est1; |
| 121 | info->est2 = est2; |
| 122 | return true; |
| 123 | |
| 124 | err2: |
| 125 | xt_rateest_put(est1); |
| 126 | err1: |
| 127 | return false; |
| 128 | } |
| 129 | |
| 130 | static void xt_rateest_mt_destroy(const struct xt_match *match, |
| 131 | void *matchinfo) |
| 132 | { |
Jan Engelhardt | 3cf93c9 | 2008-04-14 09:56:05 +0200 | [diff] [blame] | 133 | struct xt_rateest_match_info *info = matchinfo; |
Patrick McHardy | 50c164a | 2007-12-04 13:02:19 +0100 | [diff] [blame] | 134 | |
| 135 | xt_rateest_put(info->est1); |
| 136 | if (info->est2) |
| 137 | xt_rateest_put(info->est2); |
| 138 | } |
| 139 | |
| 140 | static struct xt_match xt_rateest_match[] __read_mostly = { |
| 141 | { |
| 142 | .family = AF_INET, |
| 143 | .name = "rateest", |
| 144 | .match = xt_rateest_mt, |
| 145 | .checkentry = xt_rateest_mt_checkentry, |
| 146 | .destroy = xt_rateest_mt_destroy, |
| 147 | .matchsize = sizeof(struct xt_rateest_match_info), |
| 148 | .me = THIS_MODULE, |
| 149 | }, |
| 150 | { |
| 151 | .family = AF_INET6, |
| 152 | .name = "rateest", |
| 153 | .match = xt_rateest_mt, |
| 154 | .checkentry = xt_rateest_mt_checkentry, |
| 155 | .destroy = xt_rateest_mt_destroy, |
| 156 | .matchsize = sizeof(struct xt_rateest_match_info), |
| 157 | .me = THIS_MODULE, |
| 158 | }, |
| 159 | }; |
| 160 | |
| 161 | static int __init xt_rateest_mt_init(void) |
| 162 | { |
| 163 | return xt_register_matches(xt_rateest_match, |
| 164 | ARRAY_SIZE(xt_rateest_match)); |
| 165 | } |
| 166 | |
| 167 | static void __exit xt_rateest_mt_fini(void) |
| 168 | { |
| 169 | xt_unregister_matches(xt_rateest_match, ARRAY_SIZE(xt_rateest_match)); |
| 170 | } |
| 171 | |
| 172 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); |
| 173 | MODULE_LICENSE("GPL"); |
| 174 | MODULE_DESCRIPTION("xtables rate estimator match"); |
| 175 | MODULE_ALIAS("ipt_rateest"); |
| 176 | MODULE_ALIAS("ip6t_rateest"); |
| 177 | module_init(xt_rateest_mt_init); |
| 178 | module_exit(xt_rateest_mt_fini); |