1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * (C) 2007 Patrick McHardy <kaber@trash.net> |
4 | */ |
5 | #include <linux/module.h> |
6 | #include <linux/skbuff.h> |
7 | #include <linux/gen_stats.h> |
8 | |
9 | #include <linux/netfilter/x_tables.h> |
10 | #include <linux/netfilter/xt_rateest.h> |
11 | #include <net/netfilter/xt_rateest.h> |
12 | |
13 | |
14 | static bool |
15 | xt_rateest_mt(const struct sk_buff *skb, struct xt_action_param *par) |
16 | { |
17 | const struct xt_rateest_match_info *info = par->matchinfo; |
18 | struct gnet_stats_rate_est64 sample = {0}; |
19 | u_int32_t bps1, bps2, pps1, pps2; |
20 | bool ret = true; |
21 | |
22 | gen_estimator_read(ptr: &info->est1->rate_est, sample: &sample); |
23 | |
24 | if (info->flags & XT_RATEEST_MATCH_DELTA) { |
25 | bps1 = info->bps1 >= sample.bps ? info->bps1 - sample.bps : 0; |
26 | pps1 = info->pps1 >= sample.pps ? info->pps1 - sample.pps : 0; |
27 | } else { |
28 | bps1 = sample.bps; |
29 | pps1 = sample.pps; |
30 | } |
31 | |
32 | if (info->flags & XT_RATEEST_MATCH_ABS) { |
33 | bps2 = info->bps2; |
34 | pps2 = info->pps2; |
35 | } else { |
36 | gen_estimator_read(ptr: &info->est2->rate_est, sample: &sample); |
37 | |
38 | if (info->flags & XT_RATEEST_MATCH_DELTA) { |
39 | bps2 = info->bps2 >= sample.bps ? info->bps2 - sample.bps : 0; |
40 | pps2 = info->pps2 >= sample.pps ? info->pps2 - sample.pps : 0; |
41 | } else { |
42 | bps2 = sample.bps; |
43 | pps2 = sample.pps; |
44 | } |
45 | } |
46 | |
47 | switch (info->mode) { |
48 | case XT_RATEEST_MATCH_LT: |
49 | if (info->flags & XT_RATEEST_MATCH_BPS) |
50 | ret &= bps1 < bps2; |
51 | if (info->flags & XT_RATEEST_MATCH_PPS) |
52 | ret &= pps1 < pps2; |
53 | break; |
54 | case XT_RATEEST_MATCH_GT: |
55 | if (info->flags & XT_RATEEST_MATCH_BPS) |
56 | ret &= bps1 > bps2; |
57 | if (info->flags & XT_RATEEST_MATCH_PPS) |
58 | ret &= pps1 > pps2; |
59 | break; |
60 | case XT_RATEEST_MATCH_EQ: |
61 | if (info->flags & XT_RATEEST_MATCH_BPS) |
62 | ret &= bps1 == bps2; |
63 | if (info->flags & XT_RATEEST_MATCH_PPS) |
64 | ret &= pps1 == pps2; |
65 | break; |
66 | } |
67 | |
68 | ret ^= info->flags & XT_RATEEST_MATCH_INVERT ? true : false; |
69 | return ret; |
70 | } |
71 | |
72 | static int xt_rateest_mt_checkentry(const struct xt_mtchk_param *par) |
73 | { |
74 | struct xt_rateest_match_info *info = par->matchinfo; |
75 | struct xt_rateest *est1, *est2; |
76 | int ret = -EINVAL; |
77 | |
78 | if (hweight32(info->flags & (XT_RATEEST_MATCH_ABS | |
79 | XT_RATEEST_MATCH_REL)) != 1) |
80 | goto err1; |
81 | |
82 | if (!(info->flags & (XT_RATEEST_MATCH_BPS | XT_RATEEST_MATCH_PPS))) |
83 | goto err1; |
84 | |
85 | switch (info->mode) { |
86 | case XT_RATEEST_MATCH_EQ: |
87 | case XT_RATEEST_MATCH_LT: |
88 | case XT_RATEEST_MATCH_GT: |
89 | break; |
90 | default: |
91 | goto err1; |
92 | } |
93 | |
94 | ret = -ENOENT; |
95 | est1 = xt_rateest_lookup(net: par->net, name: info->name1); |
96 | if (!est1) |
97 | goto err1; |
98 | |
99 | est2 = NULL; |
100 | if (info->flags & XT_RATEEST_MATCH_REL) { |
101 | est2 = xt_rateest_lookup(net: par->net, name: info->name2); |
102 | if (!est2) |
103 | goto err2; |
104 | } |
105 | |
106 | info->est1 = est1; |
107 | info->est2 = est2; |
108 | return 0; |
109 | |
110 | err2: |
111 | xt_rateest_put(net: par->net, est: est1); |
112 | err1: |
113 | return ret; |
114 | } |
115 | |
116 | static void xt_rateest_mt_destroy(const struct xt_mtdtor_param *par) |
117 | { |
118 | struct xt_rateest_match_info *info = par->matchinfo; |
119 | |
120 | xt_rateest_put(net: par->net, est: info->est1); |
121 | if (info->est2) |
122 | xt_rateest_put(net: par->net, est: info->est2); |
123 | } |
124 | |
125 | static struct xt_match xt_rateest_mt_reg __read_mostly = { |
126 | .name = "rateest" , |
127 | .revision = 0, |
128 | .family = NFPROTO_UNSPEC, |
129 | .match = xt_rateest_mt, |
130 | .checkentry = xt_rateest_mt_checkentry, |
131 | .destroy = xt_rateest_mt_destroy, |
132 | .matchsize = sizeof(struct xt_rateest_match_info), |
133 | .usersize = offsetof(struct xt_rateest_match_info, est1), |
134 | .me = THIS_MODULE, |
135 | }; |
136 | |
137 | static int __init xt_rateest_mt_init(void) |
138 | { |
139 | return xt_register_match(target: &xt_rateest_mt_reg); |
140 | } |
141 | |
142 | static void __exit xt_rateest_mt_fini(void) |
143 | { |
144 | xt_unregister_match(target: &xt_rateest_mt_reg); |
145 | } |
146 | |
147 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>" ); |
148 | MODULE_LICENSE("GPL" ); |
149 | MODULE_DESCRIPTION("xtables rate estimator match" ); |
150 | MODULE_ALIAS("ipt_rateest" ); |
151 | MODULE_ALIAS("ip6t_rateest" ); |
152 | module_init(xt_rateest_mt_init); |
153 | module_exit(xt_rateest_mt_fini); |
154 | |