1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
4 *
5 * Development of this code funded by Astaro AG (http://www.astaro.com/)
6 */
7
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
nft_immediate_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)18 void 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
27 static 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
nft_reg_to_type(const struct nlattr * nla)32 static enum nft_data_types nft_reg_to_type(const struct nlattr *nla)
33 {
34 enum nft_data_types type;
35 u8 reg;
36
37 reg = ntohl(nla_get_be32(nla));
38 if (reg == NFT_REG_VERDICT)
39 type = NFT_DATA_VERDICT;
40 else
41 type = NFT_DATA_VALUE;
42
43 return type;
44 }
45
nft_immediate_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])46 static int nft_immediate_init(const struct nft_ctx *ctx,
47 const struct nft_expr *expr,
48 const struct nlattr * const tb[])
49 {
50 struct nft_immediate_expr *priv = nft_expr_priv(expr);
51 struct nft_data_desc desc = {
52 .size = sizeof(priv->data),
53 };
54 int err;
55
56 if (tb[NFTA_IMMEDIATE_DREG] == NULL ||
57 tb[NFTA_IMMEDIATE_DATA] == NULL)
58 return -EINVAL;
59
60 desc.type = nft_reg_to_type(tb[NFTA_IMMEDIATE_DREG]);
61 err = nft_data_init(ctx, &priv->data, &desc, tb[NFTA_IMMEDIATE_DATA]);
62 if (err < 0)
63 return err;
64
65 priv->dlen = desc.len;
66
67 err = nft_parse_register_store(ctx, tb[NFTA_IMMEDIATE_DREG],
68 &priv->dreg, &priv->data, desc.type,
69 desc.len);
70 if (err < 0)
71 goto err1;
72
73 if (priv->dreg == NFT_REG_VERDICT) {
74 struct nft_chain *chain = priv->data.verdict.chain;
75
76 switch (priv->data.verdict.code) {
77 case NFT_JUMP:
78 case NFT_GOTO:
79 if (nft_chain_is_bound(chain)) {
80 err = -EBUSY;
81 goto err1;
82 }
83 chain->bound = true;
84 break;
85 default:
86 break;
87 }
88 }
89
90 return 0;
91
92 err1:
93 nft_data_release(&priv->data, desc.type);
94 return err;
95 }
96
nft_immediate_activate(const struct nft_ctx * ctx,const struct nft_expr * expr)97 static void nft_immediate_activate(const struct nft_ctx *ctx,
98 const struct nft_expr *expr)
99 {
100 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
101
102 return nft_data_hold(&priv->data, nft_dreg_to_type(priv->dreg));
103 }
104
nft_immediate_deactivate(const struct nft_ctx * ctx,const struct nft_expr * expr,enum nft_trans_phase phase)105 static void nft_immediate_deactivate(const struct nft_ctx *ctx,
106 const struct nft_expr *expr,
107 enum nft_trans_phase phase)
108 {
109 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
110
111 if (phase == NFT_TRANS_COMMIT)
112 return;
113
114 return nft_data_release(&priv->data, nft_dreg_to_type(priv->dreg));
115 }
116
nft_immediate_destroy(const struct nft_ctx * ctx,const struct nft_expr * expr)117 static void nft_immediate_destroy(const struct nft_ctx *ctx,
118 const struct nft_expr *expr)
119 {
120 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
121 const struct nft_data *data = &priv->data;
122 struct nft_rule *rule, *n;
123 struct nft_ctx chain_ctx;
124 struct nft_chain *chain;
125
126 if (priv->dreg != NFT_REG_VERDICT)
127 return;
128
129 switch (data->verdict.code) {
130 case NFT_JUMP:
131 case NFT_GOTO:
132 chain = data->verdict.chain;
133
134 if (!nft_chain_is_bound(chain))
135 break;
136
137 chain_ctx = *ctx;
138 chain_ctx.chain = chain;
139
140 list_for_each_entry_safe(rule, n, &chain->rules, list)
141 nf_tables_rule_release(&chain_ctx, rule);
142
143 nf_tables_chain_destroy(&chain_ctx);
144 break;
145 default:
146 break;
147 }
148 }
149
nft_immediate_dump(struct sk_buff * skb,const struct nft_expr * expr,bool reset)150 static int nft_immediate_dump(struct sk_buff *skb,
151 const struct nft_expr *expr, bool reset)
152 {
153 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
154
155 if (nft_dump_register(skb, NFTA_IMMEDIATE_DREG, priv->dreg))
156 goto nla_put_failure;
157
158 return nft_data_dump(skb, NFTA_IMMEDIATE_DATA, &priv->data,
159 nft_dreg_to_type(priv->dreg), priv->dlen);
160
161 nla_put_failure:
162 return -1;
163 }
164
nft_immediate_validate(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nft_data ** d)165 static int nft_immediate_validate(const struct nft_ctx *ctx,
166 const struct nft_expr *expr,
167 const struct nft_data **d)
168 {
169 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
170 struct nft_ctx *pctx = (struct nft_ctx *)ctx;
171 const struct nft_data *data;
172 int err;
173
174 if (priv->dreg != NFT_REG_VERDICT)
175 return 0;
176
177 data = &priv->data;
178
179 switch (data->verdict.code) {
180 case NFT_JUMP:
181 case NFT_GOTO:
182 pctx->level++;
183 err = nft_chain_validate(ctx, data->verdict.chain);
184 if (err < 0)
185 return err;
186 pctx->level--;
187 break;
188 default:
189 break;
190 }
191
192 return 0;
193 }
194
nft_immediate_offload_verdict(struct nft_offload_ctx * ctx,struct nft_flow_rule * flow,const struct nft_immediate_expr * priv)195 static int nft_immediate_offload_verdict(struct nft_offload_ctx *ctx,
196 struct nft_flow_rule *flow,
197 const struct nft_immediate_expr *priv)
198 {
199 struct flow_action_entry *entry;
200 const struct nft_data *data;
201
202 entry = &flow->rule->action.entries[ctx->num_actions++];
203
204 data = &priv->data;
205 switch (data->verdict.code) {
206 case NF_ACCEPT:
207 entry->id = FLOW_ACTION_ACCEPT;
208 break;
209 case NF_DROP:
210 entry->id = FLOW_ACTION_DROP;
211 break;
212 default:
213 return -EOPNOTSUPP;
214 }
215
216 return 0;
217 }
218
nft_immediate_offload(struct nft_offload_ctx * ctx,struct nft_flow_rule * flow,const struct nft_expr * expr)219 static int nft_immediate_offload(struct nft_offload_ctx *ctx,
220 struct nft_flow_rule *flow,
221 const struct nft_expr *expr)
222 {
223 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
224
225 if (priv->dreg == NFT_REG_VERDICT)
226 return nft_immediate_offload_verdict(ctx, flow, priv);
227
228 memcpy(&ctx->regs[priv->dreg].data, &priv->data, sizeof(priv->data));
229
230 return 0;
231 }
232
nft_immediate_offload_action(const struct nft_expr * expr)233 static bool nft_immediate_offload_action(const struct nft_expr *expr)
234 {
235 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
236
237 if (priv->dreg == NFT_REG_VERDICT)
238 return true;
239
240 return false;
241 }
242
nft_immediate_reduce(struct nft_regs_track * track,const struct nft_expr * expr)243 static bool nft_immediate_reduce(struct nft_regs_track *track,
244 const struct nft_expr *expr)
245 {
246 const struct nft_immediate_expr *priv = nft_expr_priv(expr);
247
248 if (priv->dreg != NFT_REG_VERDICT)
249 nft_reg_track_cancel(track, priv->dreg, priv->dlen);
250
251 return false;
252 }
253
254 static const struct nft_expr_ops nft_imm_ops = {
255 .type = &nft_imm_type,
256 .size = NFT_EXPR_SIZE(sizeof(struct nft_immediate_expr)),
257 .eval = nft_immediate_eval,
258 .init = nft_immediate_init,
259 .activate = nft_immediate_activate,
260 .deactivate = nft_immediate_deactivate,
261 .destroy = nft_immediate_destroy,
262 .dump = nft_immediate_dump,
263 .validate = nft_immediate_validate,
264 .reduce = nft_immediate_reduce,
265 .offload = nft_immediate_offload,
266 .offload_action = nft_immediate_offload_action,
267 };
268
269 struct nft_expr_type nft_imm_type __read_mostly = {
270 .name = "immediate",
271 .ops = &nft_imm_ops,
272 .policy = nft_immediate_policy,
273 .maxattr = NFTA_IMMEDIATE_MAX,
274 .owner = THIS_MODULE,
275 };
276