Commit | Line | Data |
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96518518 | 1 | /* |
ef1f7df9 | 2 | * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> |
96518518 PM |
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/netlink.h> | |
15 | #include <linux/netfilter.h> | |
16 | #include <linux/netfilter/nf_tables.h> | |
17 | #include <net/netfilter/nf_tables.h> | |
18 | #include <net/netfilter/nf_conntrack.h> | |
19 | #include <net/netfilter/nf_conntrack_tuple.h> | |
20 | #include <net/netfilter/nf_conntrack_helper.h> | |
21 | ||
22 | struct nft_ct { | |
23 | enum nft_ct_keys key:8; | |
24 | enum ip_conntrack_dir dir:8; | |
25 | enum nft_registers dreg:8; | |
26 | uint8_t family; | |
27 | }; | |
28 | ||
29 | static void nft_ct_eval(const struct nft_expr *expr, | |
30 | struct nft_data data[NFT_REG_MAX + 1], | |
31 | const struct nft_pktinfo *pkt) | |
32 | { | |
33 | const struct nft_ct *priv = nft_expr_priv(expr); | |
34 | struct nft_data *dest = &data[priv->dreg]; | |
35 | enum ip_conntrack_info ctinfo; | |
36 | const struct nf_conn *ct; | |
37 | const struct nf_conn_help *help; | |
38 | const struct nf_conntrack_tuple *tuple; | |
39 | const struct nf_conntrack_helper *helper; | |
40 | long diff; | |
41 | unsigned int state; | |
42 | ||
43 | ct = nf_ct_get(pkt->skb, &ctinfo); | |
44 | ||
45 | switch (priv->key) { | |
46 | case NFT_CT_STATE: | |
47 | if (ct == NULL) | |
48 | state = NF_CT_STATE_INVALID_BIT; | |
49 | else if (nf_ct_is_untracked(ct)) | |
50 | state = NF_CT_STATE_UNTRACKED_BIT; | |
51 | else | |
52 | state = NF_CT_STATE_BIT(ctinfo); | |
53 | dest->data[0] = state; | |
54 | return; | |
55 | } | |
56 | ||
57 | if (ct == NULL) | |
58 | goto err; | |
59 | ||
60 | switch (priv->key) { | |
61 | case NFT_CT_DIRECTION: | |
62 | dest->data[0] = CTINFO2DIR(ctinfo); | |
63 | return; | |
64 | case NFT_CT_STATUS: | |
65 | dest->data[0] = ct->status; | |
66 | return; | |
67 | #ifdef CONFIG_NF_CONNTRACK_MARK | |
68 | case NFT_CT_MARK: | |
69 | dest->data[0] = ct->mark; | |
70 | return; | |
71 | #endif | |
72 | #ifdef CONFIG_NF_CONNTRACK_SECMARK | |
73 | case NFT_CT_SECMARK: | |
74 | dest->data[0] = ct->secmark; | |
75 | return; | |
76 | #endif | |
77 | case NFT_CT_EXPIRATION: | |
78 | diff = (long)jiffies - (long)ct->timeout.expires; | |
79 | if (diff < 0) | |
80 | diff = 0; | |
81 | dest->data[0] = jiffies_to_msecs(diff); | |
82 | return; | |
83 | case NFT_CT_HELPER: | |
84 | if (ct->master == NULL) | |
85 | goto err; | |
86 | help = nfct_help(ct->master); | |
87 | if (help == NULL) | |
88 | goto err; | |
89 | helper = rcu_dereference(help->helper); | |
90 | if (helper == NULL) | |
91 | goto err; | |
92 | if (strlen(helper->name) >= sizeof(dest->data)) | |
93 | goto err; | |
94 | strncpy((char *)dest->data, helper->name, sizeof(dest->data)); | |
95 | return; | |
96 | } | |
97 | ||
98 | tuple = &ct->tuplehash[priv->dir].tuple; | |
99 | switch (priv->key) { | |
100 | case NFT_CT_L3PROTOCOL: | |
101 | dest->data[0] = nf_ct_l3num(ct); | |
102 | return; | |
103 | case NFT_CT_SRC: | |
104 | memcpy(dest->data, tuple->src.u3.all, | |
105 | nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16); | |
106 | return; | |
107 | case NFT_CT_DST: | |
108 | memcpy(dest->data, tuple->dst.u3.all, | |
109 | nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16); | |
110 | return; | |
111 | case NFT_CT_PROTOCOL: | |
112 | dest->data[0] = nf_ct_protonum(ct); | |
113 | return; | |
114 | case NFT_CT_PROTO_SRC: | |
115 | dest->data[0] = (__force __u16)tuple->src.u.all; | |
116 | return; | |
117 | case NFT_CT_PROTO_DST: | |
118 | dest->data[0] = (__force __u16)tuple->dst.u.all; | |
119 | return; | |
120 | } | |
121 | return; | |
122 | err: | |
123 | data[NFT_REG_VERDICT].verdict = NFT_BREAK; | |
124 | } | |
125 | ||
126 | static const struct nla_policy nft_ct_policy[NFTA_CT_MAX + 1] = { | |
127 | [NFTA_CT_DREG] = { .type = NLA_U32 }, | |
128 | [NFTA_CT_KEY] = { .type = NLA_U32 }, | |
129 | [NFTA_CT_DIRECTION] = { .type = NLA_U8 }, | |
130 | }; | |
131 | ||
132 | static int nft_ct_init(const struct nft_ctx *ctx, | |
133 | const struct nft_expr *expr, | |
134 | const struct nlattr * const tb[]) | |
135 | { | |
136 | struct nft_ct *priv = nft_expr_priv(expr); | |
137 | int err; | |
138 | ||
139 | if (tb[NFTA_CT_DREG] == NULL || | |
140 | tb[NFTA_CT_KEY] == NULL) | |
141 | return -EINVAL; | |
142 | ||
143 | priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY])); | |
144 | if (tb[NFTA_CT_DIRECTION] != NULL) { | |
145 | priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]); | |
146 | switch (priv->dir) { | |
147 | case IP_CT_DIR_ORIGINAL: | |
148 | case IP_CT_DIR_REPLY: | |
149 | break; | |
150 | default: | |
151 | return -EINVAL; | |
152 | } | |
153 | } | |
154 | ||
155 | switch (priv->key) { | |
156 | case NFT_CT_STATE: | |
157 | case NFT_CT_DIRECTION: | |
158 | case NFT_CT_STATUS: | |
159 | #ifdef CONFIG_NF_CONNTRACK_MARK | |
160 | case NFT_CT_MARK: | |
161 | #endif | |
162 | #ifdef CONFIG_NF_CONNTRACK_SECMARK | |
163 | case NFT_CT_SECMARK: | |
164 | #endif | |
165 | case NFT_CT_EXPIRATION: | |
166 | case NFT_CT_HELPER: | |
167 | if (tb[NFTA_CT_DIRECTION] != NULL) | |
168 | return -EINVAL; | |
169 | break; | |
170 | case NFT_CT_PROTOCOL: | |
171 | case NFT_CT_SRC: | |
172 | case NFT_CT_DST: | |
173 | case NFT_CT_PROTO_SRC: | |
174 | case NFT_CT_PROTO_DST: | |
175 | if (tb[NFTA_CT_DIRECTION] == NULL) | |
176 | return -EINVAL; | |
177 | break; | |
178 | default: | |
179 | return -EOPNOTSUPP; | |
180 | } | |
181 | ||
182 | err = nf_ct_l3proto_try_module_get(ctx->afi->family); | |
183 | if (err < 0) | |
184 | return err; | |
185 | priv->family = ctx->afi->family; | |
186 | ||
187 | priv->dreg = ntohl(nla_get_be32(tb[NFTA_CT_DREG])); | |
188 | err = nft_validate_output_register(priv->dreg); | |
189 | if (err < 0) | |
190 | goto err1; | |
191 | ||
192 | err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE); | |
193 | if (err < 0) | |
194 | goto err1; | |
195 | return 0; | |
196 | ||
197 | err1: | |
198 | nf_ct_l3proto_module_put(ctx->afi->family); | |
199 | return err; | |
200 | } | |
201 | ||
202 | static void nft_ct_destroy(const struct nft_expr *expr) | |
203 | { | |
204 | struct nft_ct *priv = nft_expr_priv(expr); | |
205 | ||
206 | nf_ct_l3proto_module_put(priv->family); | |
207 | } | |
208 | ||
209 | static int nft_ct_dump(struct sk_buff *skb, const struct nft_expr *expr) | |
210 | { | |
211 | const struct nft_ct *priv = nft_expr_priv(expr); | |
212 | ||
213 | if (nla_put_be32(skb, NFTA_CT_DREG, htonl(priv->dreg))) | |
214 | goto nla_put_failure; | |
215 | if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key))) | |
216 | goto nla_put_failure; | |
217 | if (nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir)) | |
218 | goto nla_put_failure; | |
219 | return 0; | |
220 | ||
221 | nla_put_failure: | |
222 | return -1; | |
223 | } | |
224 | ||
ef1f7df9 PM |
225 | static struct nft_expr_type nft_ct_type; |
226 | static const struct nft_expr_ops nft_ct_ops = { | |
227 | .type = &nft_ct_type, | |
96518518 | 228 | .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)), |
96518518 PM |
229 | .eval = nft_ct_eval, |
230 | .init = nft_ct_init, | |
231 | .destroy = nft_ct_destroy, | |
232 | .dump = nft_ct_dump, | |
ef1f7df9 PM |
233 | }; |
234 | ||
235 | static struct nft_expr_type nft_ct_type __read_mostly = { | |
236 | .name = "ct", | |
237 | .ops = &nft_ct_ops, | |
96518518 PM |
238 | .policy = nft_ct_policy, |
239 | .maxattr = NFTA_CT_MAX, | |
ef1f7df9 | 240 | .owner = THIS_MODULE, |
96518518 PM |
241 | }; |
242 | ||
243 | static int __init nft_ct_module_init(void) | |
244 | { | |
ef1f7df9 | 245 | return nft_register_expr(&nft_ct_type); |
96518518 PM |
246 | } |
247 | ||
248 | static void __exit nft_ct_module_exit(void) | |
249 | { | |
ef1f7df9 | 250 | nft_unregister_expr(&nft_ct_type); |
96518518 PM |
251 | } |
252 | ||
253 | module_init(nft_ct_module_init); | |
254 | module_exit(nft_ct_module_exit); | |
255 | ||
256 | MODULE_LICENSE("GPL"); | |
257 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); | |
258 | MODULE_ALIAS_NFT_EXPR("ct"); |