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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2012-2016 Pablo Neira Ayuso <pablo@netfilter.org>
4 */
5
6#include <linux/init.h>
7#include <linux/module.h>
8#include <linux/skbuff.h>
9#include <linux/netlink.h>
10#include <linux/netfilter.h>
11#include <linux/netfilter/nf_tables.h>
12#include <net/netfilter/nf_tables_core.h>
13
14#define nft_objref_priv(expr) *((struct nft_object **)nft_expr_priv(expr))
15
16static void nft_objref_eval(const struct nft_expr *expr,
17 struct nft_regs *regs,
18 const struct nft_pktinfo *pkt)
19{
20 struct nft_object *obj = nft_objref_priv(expr);
21
22 obj->ops->eval(obj, regs, pkt);
23}
24
25static int nft_objref_init(const struct nft_ctx *ctx,
26 const struct nft_expr *expr,
27 const struct nlattr * const tb[])
28{
29 struct nft_object *obj = nft_objref_priv(expr);
30 u8 genmask = nft_genmask_next(ctx->net);
31 u32 objtype;
32
33 if (!tb[NFTA_OBJREF_IMM_NAME] ||
34 !tb[NFTA_OBJREF_IMM_TYPE])
35 return -EINVAL;
36
37 objtype = ntohl(nla_get_be32(tb[NFTA_OBJREF_IMM_TYPE]));
38 obj = nft_obj_lookup(ctx->net, ctx->table,
39 tb[NFTA_OBJREF_IMM_NAME], objtype,
40 genmask);
41 if (IS_ERR(obj))
42 return -ENOENT;
43
44 nft_objref_priv(expr) = obj;
45 obj->use++;
46
47 return 0;
48}
49
50static int nft_objref_dump(struct sk_buff *skb, const struct nft_expr *expr)
51{
52 const struct nft_object *obj = nft_objref_priv(expr);
53
54 if (nla_put_string(skb, NFTA_OBJREF_IMM_NAME, obj->key.name) ||
55 nla_put_be32(skb, NFTA_OBJREF_IMM_TYPE,
56 htonl(obj->ops->type->type)))
57 goto nla_put_failure;
58
59 return 0;
60
61nla_put_failure:
62 return -1;
63}
64
65static void nft_objref_deactivate(const struct nft_ctx *ctx,
66 const struct nft_expr *expr,
67 enum nft_trans_phase phase)
68{
69 struct nft_object *obj = nft_objref_priv(expr);
70
71 if (phase == NFT_TRANS_COMMIT)
72 return;
73
74 obj->use--;
75}
76
77static void nft_objref_activate(const struct nft_ctx *ctx,
78 const struct nft_expr *expr)
79{
80 struct nft_object *obj = nft_objref_priv(expr);
81
82 obj->use++;
83}
84
85static struct nft_expr_type nft_objref_type;
86static const struct nft_expr_ops nft_objref_ops = {
87 .type = &nft_objref_type,
88 .size = NFT_EXPR_SIZE(sizeof(struct nft_object *)),
89 .eval = nft_objref_eval,
90 .init = nft_objref_init,
91 .activate = nft_objref_activate,
92 .deactivate = nft_objref_deactivate,
93 .dump = nft_objref_dump,
94};
95
96struct nft_objref_map {
97 struct nft_set *set;
98 u8 sreg;
99 struct nft_set_binding binding;
100};
101
102static void nft_objref_map_eval(const struct nft_expr *expr,
103 struct nft_regs *regs,
104 const struct nft_pktinfo *pkt)
105{
106 struct nft_objref_map *priv = nft_expr_priv(expr);
107 const struct nft_set *set = priv->set;
108 struct net *net = nft_net(pkt);
109 const struct nft_set_ext *ext;
110 struct nft_object *obj;
111 bool found;
112
113 found = nft_set_do_lookup(net, set, ®s->data[priv->sreg], &ext);
114 if (!found) {
115 ext = nft_set_catchall_lookup(net, set);
116 if (!ext) {
117 regs->verdict.code = NFT_BREAK;
118 return;
119 }
120 }
121 obj = *nft_set_ext_obj(ext);
122 obj->ops->eval(obj, regs, pkt);
123}
124
125static int nft_objref_map_init(const struct nft_ctx *ctx,
126 const struct nft_expr *expr,
127 const struct nlattr * const tb[])
128{
129 struct nft_objref_map *priv = nft_expr_priv(expr);
130 u8 genmask = nft_genmask_next(ctx->net);
131 struct nft_set *set;
132 int err;
133
134 set = nft_set_lookup_global(ctx->net, ctx->table,
135 tb[NFTA_OBJREF_SET_NAME],
136 tb[NFTA_OBJREF_SET_ID], genmask);
137 if (IS_ERR(set))
138 return PTR_ERR(set);
139
140 if (!(set->flags & NFT_SET_OBJECT))
141 return -EINVAL;
142
143 err = nft_parse_register_load(tb[NFTA_OBJREF_SET_SREG], &priv->sreg,
144 set->klen);
145 if (err < 0)
146 return err;
147
148 priv->binding.flags = set->flags & NFT_SET_OBJECT;
149
150 err = nf_tables_bind_set(ctx, set, &priv->binding);
151 if (err < 0)
152 return err;
153
154 priv->set = set;
155 return 0;
156}
157
158static int nft_objref_map_dump(struct sk_buff *skb, const struct nft_expr *expr)
159{
160 const struct nft_objref_map *priv = nft_expr_priv(expr);
161
162 if (nft_dump_register(skb, NFTA_OBJREF_SET_SREG, priv->sreg) ||
163 nla_put_string(skb, NFTA_OBJREF_SET_NAME, priv->set->name))
164 goto nla_put_failure;
165
166 return 0;
167
168nla_put_failure:
169 return -1;
170}
171
172static void nft_objref_map_deactivate(const struct nft_ctx *ctx,
173 const struct nft_expr *expr,
174 enum nft_trans_phase phase)
175{
176 struct nft_objref_map *priv = nft_expr_priv(expr);
177
178 nf_tables_deactivate_set(ctx, priv->set, &priv->binding, phase);
179}
180
181static void nft_objref_map_activate(const struct nft_ctx *ctx,
182 const struct nft_expr *expr)
183{
184 struct nft_objref_map *priv = nft_expr_priv(expr);
185
186 priv->set->use++;
187}
188
189static void nft_objref_map_destroy(const struct nft_ctx *ctx,
190 const struct nft_expr *expr)
191{
192 struct nft_objref_map *priv = nft_expr_priv(expr);
193
194 nf_tables_destroy_set(ctx, priv->set);
195}
196
197static struct nft_expr_type nft_objref_type;
198static const struct nft_expr_ops nft_objref_map_ops = {
199 .type = &nft_objref_type,
200 .size = NFT_EXPR_SIZE(sizeof(struct nft_objref_map)),
201 .eval = nft_objref_map_eval,
202 .init = nft_objref_map_init,
203 .activate = nft_objref_map_activate,
204 .deactivate = nft_objref_map_deactivate,
205 .destroy = nft_objref_map_destroy,
206 .dump = nft_objref_map_dump,
207};
208
209static const struct nft_expr_ops *
210nft_objref_select_ops(const struct nft_ctx *ctx,
211 const struct nlattr * const tb[])
212{
213 if (tb[NFTA_OBJREF_SET_SREG] &&
214 (tb[NFTA_OBJREF_SET_NAME] ||
215 tb[NFTA_OBJREF_SET_ID]))
216 return &nft_objref_map_ops;
217 else if (tb[NFTA_OBJREF_IMM_NAME] &&
218 tb[NFTA_OBJREF_IMM_TYPE])
219 return &nft_objref_ops;
220
221 return ERR_PTR(-EOPNOTSUPP);
222}
223
224static const struct nla_policy nft_objref_policy[NFTA_OBJREF_MAX + 1] = {
225 [NFTA_OBJREF_IMM_NAME] = { .type = NLA_STRING,
226 .len = NFT_OBJ_MAXNAMELEN - 1 },
227 [NFTA_OBJREF_IMM_TYPE] = { .type = NLA_U32 },
228 [NFTA_OBJREF_SET_SREG] = { .type = NLA_U32 },
229 [NFTA_OBJREF_SET_NAME] = { .type = NLA_STRING,
230 .len = NFT_SET_MAXNAMELEN - 1 },
231 [NFTA_OBJREF_SET_ID] = { .type = NLA_U32 },
232};
233
234static struct nft_expr_type nft_objref_type __read_mostly = {
235 .name = "objref",
236 .select_ops = nft_objref_select_ops,
237 .policy = nft_objref_policy,
238 .maxattr = NFTA_OBJREF_MAX,
239 .owner = THIS_MODULE,
240};
241
242static int __init nft_objref_module_init(void)
243{
244 return nft_register_expr(&nft_objref_type);
245}
246
247static void __exit nft_objref_module_exit(void)
248{
249 nft_unregister_expr(&nft_objref_type);
250}
251
252module_init(nft_objref_module_init);
253module_exit(nft_objref_module_exit);
254
255MODULE_LICENSE("GPL");
256MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
257MODULE_ALIAS_NFT_EXPR("objref");
258MODULE_DESCRIPTION("nftables stateful object reference module");
1/*
2 * Copyright (c) 2012-2016 Pablo Neira Ayuso <pablo@netfilter.org>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 */
8
9#include <linux/init.h>
10#include <linux/module.h>
11#include <linux/skbuff.h>
12#include <linux/netlink.h>
13#include <linux/netfilter.h>
14#include <linux/netfilter/nf_tables.h>
15#include <net/netfilter/nf_tables.h>
16
17#define nft_objref_priv(expr) *((struct nft_object **)nft_expr_priv(expr))
18
19static void nft_objref_eval(const struct nft_expr *expr,
20 struct nft_regs *regs,
21 const struct nft_pktinfo *pkt)
22{
23 struct nft_object *obj = nft_objref_priv(expr);
24
25 obj->type->eval(obj, regs, pkt);
26}
27
28static int nft_objref_init(const struct nft_ctx *ctx,
29 const struct nft_expr *expr,
30 const struct nlattr * const tb[])
31{
32 struct nft_object *obj = nft_objref_priv(expr);
33 u8 genmask = nft_genmask_next(ctx->net);
34 u32 objtype;
35
36 if (!tb[NFTA_OBJREF_IMM_NAME] ||
37 !tb[NFTA_OBJREF_IMM_TYPE])
38 return -EINVAL;
39
40 objtype = ntohl(nla_get_be32(tb[NFTA_OBJREF_IMM_TYPE]));
41 obj = nf_tables_obj_lookup(ctx->table, tb[NFTA_OBJREF_IMM_NAME], objtype,
42 genmask);
43 if (IS_ERR(obj))
44 return -ENOENT;
45
46 nft_objref_priv(expr) = obj;
47 obj->use++;
48
49 return 0;
50}
51
52static int nft_objref_dump(struct sk_buff *skb, const struct nft_expr *expr)
53{
54 const struct nft_object *obj = nft_objref_priv(expr);
55
56 if (nla_put_string(skb, NFTA_OBJREF_IMM_NAME, obj->name) ||
57 nla_put_be32(skb, NFTA_OBJREF_IMM_TYPE, htonl(obj->type->type)))
58 goto nla_put_failure;
59
60 return 0;
61
62nla_put_failure:
63 return -1;
64}
65
66static void nft_objref_destroy(const struct nft_ctx *ctx,
67 const struct nft_expr *expr)
68{
69 struct nft_object *obj = nft_objref_priv(expr);
70
71 obj->use--;
72}
73
74static struct nft_expr_type nft_objref_type;
75static const struct nft_expr_ops nft_objref_ops = {
76 .type = &nft_objref_type,
77 .size = NFT_EXPR_SIZE(sizeof(struct nft_object *)),
78 .eval = nft_objref_eval,
79 .init = nft_objref_init,
80 .destroy = nft_objref_destroy,
81 .dump = nft_objref_dump,
82};
83
84struct nft_objref_map {
85 struct nft_set *set;
86 enum nft_registers sreg:8;
87 struct nft_set_binding binding;
88};
89
90static void nft_objref_map_eval(const struct nft_expr *expr,
91 struct nft_regs *regs,
92 const struct nft_pktinfo *pkt)
93{
94 struct nft_objref_map *priv = nft_expr_priv(expr);
95 const struct nft_set *set = priv->set;
96 const struct nft_set_ext *ext;
97 struct nft_object *obj;
98 bool found;
99
100 found = set->ops->lookup(nft_net(pkt), set, ®s->data[priv->sreg],
101 &ext);
102 if (!found) {
103 regs->verdict.code = NFT_BREAK;
104 return;
105 }
106 obj = *nft_set_ext_obj(ext);
107 obj->type->eval(obj, regs, pkt);
108}
109
110static int nft_objref_map_init(const struct nft_ctx *ctx,
111 const struct nft_expr *expr,
112 const struct nlattr * const tb[])
113{
114 struct nft_objref_map *priv = nft_expr_priv(expr);
115 u8 genmask = nft_genmask_next(ctx->net);
116 struct nft_set *set;
117 int err;
118
119 set = nf_tables_set_lookup(ctx->table, tb[NFTA_OBJREF_SET_NAME], genmask);
120 if (IS_ERR(set)) {
121 if (tb[NFTA_OBJREF_SET_ID]) {
122 set = nf_tables_set_lookup_byid(ctx->net,
123 tb[NFTA_OBJREF_SET_ID],
124 genmask);
125 }
126 if (IS_ERR(set))
127 return PTR_ERR(set);
128 }
129
130 if (!(set->flags & NFT_SET_OBJECT))
131 return -EINVAL;
132
133 priv->sreg = nft_parse_register(tb[NFTA_OBJREF_SET_SREG]);
134 err = nft_validate_register_load(priv->sreg, set->klen);
135 if (err < 0)
136 return err;
137
138 priv->binding.flags = set->flags & NFT_SET_OBJECT;
139
140 err = nf_tables_bind_set(ctx, set, &priv->binding);
141 if (err < 0)
142 return err;
143
144 priv->set = set;
145 return 0;
146}
147
148static int nft_objref_map_dump(struct sk_buff *skb, const struct nft_expr *expr)
149{
150 const struct nft_objref_map *priv = nft_expr_priv(expr);
151
152 if (nft_dump_register(skb, NFTA_OBJREF_SET_SREG, priv->sreg) ||
153 nla_put_string(skb, NFTA_OBJREF_SET_NAME, priv->set->name))
154 goto nla_put_failure;
155
156 return 0;
157
158nla_put_failure:
159 return -1;
160}
161
162static void nft_objref_map_destroy(const struct nft_ctx *ctx,
163 const struct nft_expr *expr)
164{
165 struct nft_objref_map *priv = nft_expr_priv(expr);
166
167 nf_tables_unbind_set(ctx, priv->set, &priv->binding);
168}
169
170static struct nft_expr_type nft_objref_type;
171static const struct nft_expr_ops nft_objref_map_ops = {
172 .type = &nft_objref_type,
173 .size = NFT_EXPR_SIZE(sizeof(struct nft_objref_map)),
174 .eval = nft_objref_map_eval,
175 .init = nft_objref_map_init,
176 .destroy = nft_objref_map_destroy,
177 .dump = nft_objref_map_dump,
178};
179
180static const struct nft_expr_ops *
181nft_objref_select_ops(const struct nft_ctx *ctx,
182 const struct nlattr * const tb[])
183{
184 if (tb[NFTA_OBJREF_SET_SREG] &&
185 (tb[NFTA_OBJREF_SET_NAME] ||
186 tb[NFTA_OBJREF_SET_ID]))
187 return &nft_objref_map_ops;
188 else if (tb[NFTA_OBJREF_IMM_NAME] &&
189 tb[NFTA_OBJREF_IMM_TYPE])
190 return &nft_objref_ops;
191
192 return ERR_PTR(-EOPNOTSUPP);
193}
194
195static const struct nla_policy nft_objref_policy[NFTA_OBJREF_MAX + 1] = {
196 [NFTA_OBJREF_IMM_NAME] = { .type = NLA_STRING,
197 .len = NFT_OBJ_MAXNAMELEN - 1 },
198 [NFTA_OBJREF_IMM_TYPE] = { .type = NLA_U32 },
199 [NFTA_OBJREF_SET_SREG] = { .type = NLA_U32 },
200 [NFTA_OBJREF_SET_NAME] = { .type = NLA_STRING,
201 .len = NFT_SET_MAXNAMELEN - 1 },
202 [NFTA_OBJREF_SET_ID] = { .type = NLA_U32 },
203};
204
205static struct nft_expr_type nft_objref_type __read_mostly = {
206 .name = "objref",
207 .select_ops = nft_objref_select_ops,
208 .policy = nft_objref_policy,
209 .maxattr = NFTA_OBJREF_MAX,
210 .owner = THIS_MODULE,
211};
212
213static int __init nft_objref_module_init(void)
214{
215 return nft_register_expr(&nft_objref_type);
216}
217
218static void __exit nft_objref_module_exit(void)
219{
220 nft_unregister_expr(&nft_objref_type);
221}
222
223module_init(nft_objref_module_init);
224module_exit(nft_objref_module_exit);
225
226MODULE_LICENSE("GPL");
227MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
228MODULE_ALIAS_NFT_EXPR("objref");