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8#include <linux/kernel.h>
9#include <linux/init.h>
10#include <linux/module.h>
11#include <linux/netlink.h>
12#include <linux/netfilter.h>
13#include <linux/netfilter/nf_tables.h>
14#include <net/netfilter/nf_tables_core.h>
15#include <net/netfilter/nf_tables.h>
16#include <net/netfilter/nf_tables_offload.h>
17
18void nft_immediate_eval(const struct nft_expr *expr,
19 struct nft_regs *regs,
20 const struct nft_pktinfo *pkt)
21{
22 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
23
24 nft_data_copy(®s->data[priv->dreg], &priv->data, priv->dlen);
25}
26
27static const struct nla_policy nft_immediate_policy[NFTA_IMMEDIATE_MAX + 1] = {
28 [NFTA_IMMEDIATE_DREG] = { .type = NLA_U32 },
29 [NFTA_IMMEDIATE_DATA] = { .type = NLA_NESTED },
30};
31
32static int nft_immediate_init(const struct nft_ctx *ctx,
33 const struct nft_expr *expr,
34 const struct nlattr * const tb[])
35{
36 struct nft_immediate_expr *priv = nft_expr_priv(expr);
37 struct nft_data_desc desc;
38 int err;
39
40 if (tb[NFTA_IMMEDIATE_DREG] == NULL ||
41 tb[NFTA_IMMEDIATE_DATA] == NULL)
42 return -EINVAL;
43
44 err = nft_data_init(ctx, &priv->data, sizeof(priv->data), &desc,
45 tb[NFTA_IMMEDIATE_DATA]);
46 if (err < 0)
47 return err;
48
49 priv->dlen = desc.len;
50
51 err = nft_parse_register_store(ctx, tb[NFTA_IMMEDIATE_DREG],
52 &priv->dreg, &priv->data, desc.type,
53 desc.len);
54 if (err < 0)
55 goto err1;
56
57 if (priv->dreg == NFT_REG_VERDICT) {
58 struct nft_chain *chain = priv->data.verdict.chain;
59
60 switch (priv->data.verdict.code) {
61 case NFT_JUMP:
62 case NFT_GOTO:
63 if (nft_chain_is_bound(chain)) {
64 err = -EBUSY;
65 goto err1;
66 }
67 chain->bound = true;
68 break;
69 default:
70 break;
71 }
72 }
73
74 return 0;
75
76err1:
77 nft_data_release(&priv->data, desc.type);
78 return err;
79}
80
81static void nft_immediate_activate(const struct nft_ctx *ctx,
82 const struct nft_expr *expr)
83{
84 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
85
86 return nft_data_hold(&priv->data, nft_dreg_to_type(priv->dreg));
87}
88
89static void nft_immediate_deactivate(const struct nft_ctx *ctx,
90 const struct nft_expr *expr,
91 enum nft_trans_phase phase)
92{
93 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
94
95 if (phase == NFT_TRANS_COMMIT)
96 return;
97
98 return nft_data_release(&priv->data, nft_dreg_to_type(priv->dreg));
99}
100
101static void nft_immediate_destroy(const struct nft_ctx *ctx,
102 const struct nft_expr *expr)
103{
104 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
105 const struct nft_data *data = &priv->data;
106 struct nft_rule *rule, *n;
107 struct nft_ctx chain_ctx;
108 struct nft_chain *chain;
109
110 if (priv->dreg != NFT_REG_VERDICT)
111 return;
112
113 switch (data->verdict.code) {
114 case NFT_JUMP:
115 case NFT_GOTO:
116 chain = data->verdict.chain;
117
118 if (!nft_chain_is_bound(chain))
119 break;
120
121 chain_ctx = *ctx;
122 chain_ctx.chain = chain;
123
124 list_for_each_entry_safe(rule, n, &chain->rules, list)
125 nf_tables_rule_release(&chain_ctx, rule);
126
127 nf_tables_chain_destroy(&chain_ctx);
128 break;
129 default:
130 break;
131 }
132}
133
134static int nft_immediate_dump(struct sk_buff *skb, const struct nft_expr *expr)
135{
136 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
137
138 if (nft_dump_register(skb, NFTA_IMMEDIATE_DREG, priv->dreg))
139 goto nla_put_failure;
140
141 return nft_data_dump(skb, NFTA_IMMEDIATE_DATA, &priv->data,
142 nft_dreg_to_type(priv->dreg), priv->dlen);
143
144nla_put_failure:
145 return -1;
146}
147
148static int nft_immediate_validate(const struct nft_ctx *ctx,
149 const struct nft_expr *expr,
150 const struct nft_data **d)
151{
152 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
153 struct nft_ctx *pctx = (struct nft_ctx *)ctx;
154 const struct nft_data *data;
155 int err;
156
157 if (priv->dreg != NFT_REG_VERDICT)
158 return 0;
159
160 data = &priv->data;
161
162 switch (data->verdict.code) {
163 case NFT_JUMP:
164 case NFT_GOTO:
165 pctx->level++;
166 err = nft_chain_validate(ctx, data->verdict.chain);
167 if (err < 0)
168 return err;
169 pctx->level--;
170 break;
171 default:
172 break;
173 }
174
175 return 0;
176}
177
178static int nft_immediate_offload_verdict(struct nft_offload_ctx *ctx,
179 struct nft_flow_rule *flow,
180 const struct nft_immediate_expr *priv)
181{
182 struct flow_action_entry *entry;
183 const struct nft_data *data;
184
185 entry = &flow->rule->action.entries[ctx->num_actions++];
186
187 data = &priv->data;
188 switch (data->verdict.code) {
189 case NF_ACCEPT:
190 entry->id = FLOW_ACTION_ACCEPT;
191 break;
192 case NF_DROP:
193 entry->id = FLOW_ACTION_DROP;
194 break;
195 default:
196 return -EOPNOTSUPP;
197 }
198
199 return 0;
200}
201
202static int nft_immediate_offload(struct nft_offload_ctx *ctx,
203 struct nft_flow_rule *flow,
204 const struct nft_expr *expr)
205{
206 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
207
208 if (priv->dreg == NFT_REG_VERDICT)
209 return nft_immediate_offload_verdict(ctx, flow, priv);
210
211 memcpy(&ctx->regs[priv->dreg].data, &priv->data, sizeof(priv->data));
212
213 return 0;
214}
215
216static const struct nft_expr_ops nft_imm_ops = {
217 .type = &nft_imm_type,
218 .size = NFT_EXPR_SIZE(sizeof(struct nft_immediate_expr)),
219 .eval = nft_immediate_eval,
220 .init = nft_immediate_init,
221 .activate = nft_immediate_activate,
222 .deactivate = nft_immediate_deactivate,
223 .destroy = nft_immediate_destroy,
224 .dump = nft_immediate_dump,
225 .validate = nft_immediate_validate,
226 .offload = nft_immediate_offload,
227 .offload_flags = NFT_OFFLOAD_F_ACTION,
228};
229
230struct nft_expr_type nft_imm_type __read_mostly = {
231 .name = "immediate",
232 .ops = &nft_imm_ops,
233 .policy = nft_immediate_policy,
234 .maxattr = NFTA_IMMEDIATE_MAX,
235 .owner = THIS_MODULE,
236};
237
