summaryrefslogtreecommitdiff
path: root/net/netfilter/nft_immediate.c
blob: d0f67d325bdfd384cd70a95d527d9ce7bc690b2d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
 *
 * Development of this code funded by Astaro AG (http://www.astaro.com/)
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_core.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_offload.h>

void nft_immediate_eval(const struct nft_expr *expr,
			struct nft_regs *regs,
			const struct nft_pktinfo *pkt)
{
	const struct nft_immediate_expr *priv = nft_expr_priv(expr);

	nft_data_copy(&regs->data[priv->dreg], &priv->data, priv->dlen);
}

static const struct nla_policy nft_immediate_policy[NFTA_IMMEDIATE_MAX + 1] = {
	[NFTA_IMMEDIATE_DREG]	= { .type = NLA_U32 },
	[NFTA_IMMEDIATE_DATA]	= { .type = NLA_NESTED },
};

static int nft_immediate_init(const struct nft_ctx *ctx,
			      const struct nft_expr *expr,
			      const struct nlattr * const tb[])
{
	struct nft_immediate_expr *priv = nft_expr_priv(expr);
	struct nft_data_desc desc;
	int err;

	if (tb[NFTA_IMMEDIATE_DREG] == NULL ||
	    tb[NFTA_IMMEDIATE_DATA] == NULL)
		return -EINVAL;

	err = nft_data_init(ctx, &priv->data, sizeof(priv->data), &desc,
			    tb[NFTA_IMMEDIATE_DATA]);
	if (err < 0)
		return err;

	priv->dlen = desc.len;

	err = nft_parse_register_store(ctx, tb[NFTA_IMMEDIATE_DREG],
				       &priv->dreg, &priv->data, desc.type,
				       desc.len);
	if (err < 0)
		goto err1;

	if (priv->dreg == NFT_REG_VERDICT) {
		struct nft_chain *chain = priv->data.verdict.chain;

		switch (priv->data.verdict.code) {
		case NFT_JUMP:
		case NFT_GOTO:
			if (nft_chain_is_bound(chain)) {
				err = -EBUSY;
				goto err1;
			}
			chain->bound = true;
			break;
		default:
			break;
		}
	}

	return 0;

err1:
	nft_data_release(&priv->data, desc.type);
	return err;
}

static void nft_immediate_activate(const struct nft_ctx *ctx,
				   const struct nft_expr *expr)
{
	const struct nft_immediate_expr *priv = nft_expr_priv(expr);

	return nft_data_hold(&priv->data, nft_dreg_to_type(priv->dreg));
}

static void nft_immediate_deactivate(const struct nft_ctx *ctx,
				     const struct nft_expr *expr,
				     enum nft_trans_phase phase)
{
	const struct nft_immediate_expr *priv = nft_expr_priv(expr);

	if (phase == NFT_TRANS_COMMIT)
		return;

	return nft_data_release(&priv->data, nft_dreg_to_type(priv->dreg));
}

static void nft_immediate_destroy(const struct nft_ctx *ctx,
				  const struct nft_expr *expr)
{
	const struct nft_immediate_expr *priv = nft_expr_priv(expr);
	const struct nft_data *data = &priv->data;
	struct nft_rule *rule, *n;
	struct nft_ctx chain_ctx;
	struct nft_chain *chain;

	if (priv->dreg != NFT_REG_VERDICT)
		return;

	switch (data->verdict.code) {
	case NFT_JUMP:
	case NFT_GOTO:
		chain = data->verdict.chain;

		if (!nft_chain_is_bound(chain))
			break;

		chain_ctx = *ctx;
		chain_ctx.chain = chain;

		list_for_each_entry_safe(rule, n, &chain->rules, list)
			nf_tables_rule_release(&chain_ctx, rule);

		nf_tables_chain_destroy(&chain_ctx);
		break;
	default:
		break;
	}
}

static int nft_immediate_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
	const struct nft_immediate_expr *priv = nft_expr_priv(expr);

	if (nft_dump_register(skb, NFTA_IMMEDIATE_DREG, priv->dreg))
		goto nla_put_failure;

	return nft_data_dump(skb, NFTA_IMMEDIATE_DATA, &priv->data,
			     nft_dreg_to_type(priv->dreg), priv->dlen);

nla_put_failure:
	return -1;
}

static int nft_immediate_validate(const struct nft_ctx *ctx,
				  const struct nft_expr *expr,
				  const struct nft_data **d)
{
	const struct nft_immediate_expr *priv = nft_expr_priv(expr);
	struct nft_ctx *pctx = (struct nft_ctx *)ctx;
	const struct nft_data *data;
	int err;

	if (priv->dreg != NFT_REG_VERDICT)
		return 0;

	data = &priv->data;

	switch (data->verdict.code) {
	case NFT_JUMP:
	case NFT_GOTO:
		pctx->level++;
		err = nft_chain_validate(ctx, data->verdict.chain);
		if (err < 0)
			return err;
		pctx->level--;
		break;
	default:
		break;
	}

	return 0;
}

static int nft_immediate_offload_verdict(struct nft_offload_ctx *ctx,
					 struct nft_flow_rule *flow,
					 const struct nft_immediate_expr *priv)
{
	struct flow_action_entry *entry;
	const struct nft_data *data;

	entry = &flow->rule->action.entries[ctx->num_actions++];

	data = &priv->data;
	switch (data->verdict.code) {
	case NF_ACCEPT:
		entry->id = FLOW_ACTION_ACCEPT;
		break;
	case NF_DROP:
		entry->id = FLOW_ACTION_DROP;
		break;
	default:
		return -EOPNOTSUPP;
	}

	return 0;
}

static int nft_immediate_offload(struct nft_offload_ctx *ctx,
				 struct nft_flow_rule *flow,
				 const struct nft_expr *expr)
{
	const struct nft_immediate_expr *priv = nft_expr_priv(expr);

	if (priv->dreg == NFT_REG_VERDICT)
		return nft_immediate_offload_verdict(ctx, flow, priv);

	memcpy(&ctx->regs[priv->dreg].data, &priv->data, sizeof(priv->data));

	return 0;
}

static bool nft_immediate_offload_action(const struct nft_expr *expr)
{
	const struct nft_immediate_expr *priv = nft_expr_priv(expr);

	if (priv->dreg == NFT_REG_VERDICT)
		return true;

	return false;
}

static const struct nft_expr_ops nft_imm_ops = {
	.type		= &nft_imm_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_immediate_expr)),
	.eval		= nft_immediate_eval,
	.init		= nft_immediate_init,
	.activate	= nft_immediate_activate,
	.deactivate	= nft_immediate_deactivate,
	.destroy	= nft_immediate_destroy,
	.dump		= nft_immediate_dump,
	.validate	= nft_immediate_validate,
	.offload	= nft_immediate_offload,
	.offload_action	= nft_immediate_offload_action,
};

struct nft_expr_type nft_imm_type __read_mostly = {
	.name		= "immediate",
	.ops		= &nft_imm_ops,
	.policy		= nft_immediate_policy,
	.maxattr	= NFTA_IMMEDIATE_MAX,
	.owner		= THIS_MODULE,
};