tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
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 <linux/in.h>
18#include <linux/ip.h>
19#include <linux/ipv6.h>
20#include <linux/smp.h>
21#include <net/dst.h>
22#include <net/sock.h>
23#include <net/tcp_states.h> /* for TCP_TIME_WAIT */
24#include <net/netfilter/nf_tables.h>
25#include <net/netfilter/nft_meta.h>
26
27void nft_meta_get_eval(const struct nft_expr *expr,
28 struct nft_regs *regs,
29 const struct nft_pktinfo *pkt)
30{
31 const struct nft_meta *priv = nft_expr_priv(expr);
32 const struct sk_buff *skb = pkt->skb;
33 const struct net_device *in = pkt->in, *out = pkt->out;
34 u32 *dest = ®s->data[priv->dreg];
35
36 switch (priv->key) {
37 case NFT_META_LEN:
38 *dest = skb->len;
39 break;
40 case NFT_META_PROTOCOL:
41 *dest = 0;
42 *(__be16 *)dest = skb->protocol;
43 break;
44 case NFT_META_NFPROTO:
45 *dest = pkt->ops->pf;
46 break;
47 case NFT_META_L4PROTO:
48 *dest = pkt->tprot;
49 break;
50 case NFT_META_PRIORITY:
51 *dest = skb->priority;
52 break;
53 case NFT_META_MARK:
54 *dest = skb->mark;
55 break;
56 case NFT_META_IIF:
57 if (in == NULL)
58 goto err;
59 *dest = in->ifindex;
60 break;
61 case NFT_META_OIF:
62 if (out == NULL)
63 goto err;
64 *dest = out->ifindex;
65 break;
66 case NFT_META_IIFNAME:
67 if (in == NULL)
68 goto err;
69 strncpy((char *)dest, in->name, IFNAMSIZ);
70 break;
71 case NFT_META_OIFNAME:
72 if (out == NULL)
73 goto err;
74 strncpy((char *)dest, out->name, IFNAMSIZ);
75 break;
76 case NFT_META_IIFTYPE:
77 if (in == NULL)
78 goto err;
79 *dest = 0;
80 *(u16 *)dest = in->type;
81 break;
82 case NFT_META_OIFTYPE:
83 if (out == NULL)
84 goto err;
85 *dest = 0;
86 *(u16 *)dest = out->type;
87 break;
88 case NFT_META_SKUID:
89 if (skb->sk == NULL || !sk_fullsock(skb->sk))
90 goto err;
91
92 read_lock_bh(&skb->sk->sk_callback_lock);
93 if (skb->sk->sk_socket == NULL ||
94 skb->sk->sk_socket->file == NULL) {
95 read_unlock_bh(&skb->sk->sk_callback_lock);
96 goto err;
97 }
98
99 *dest = from_kuid_munged(&init_user_ns,
100 skb->sk->sk_socket->file->f_cred->fsuid);
101 read_unlock_bh(&skb->sk->sk_callback_lock);
102 break;
103 case NFT_META_SKGID:
104 if (skb->sk == NULL || !sk_fullsock(skb->sk))
105 goto err;
106
107 read_lock_bh(&skb->sk->sk_callback_lock);
108 if (skb->sk->sk_socket == NULL ||
109 skb->sk->sk_socket->file == NULL) {
110 read_unlock_bh(&skb->sk->sk_callback_lock);
111 goto err;
112 }
113 *dest = from_kgid_munged(&init_user_ns,
114 skb->sk->sk_socket->file->f_cred->fsgid);
115 read_unlock_bh(&skb->sk->sk_callback_lock);
116 break;
117#ifdef CONFIG_IP_ROUTE_CLASSID
118 case NFT_META_RTCLASSID: {
119 const struct dst_entry *dst = skb_dst(skb);
120
121 if (dst == NULL)
122 goto err;
123 *dest = dst->tclassid;
124 break;
125 }
126#endif
127#ifdef CONFIG_NETWORK_SECMARK
128 case NFT_META_SECMARK:
129 *dest = skb->secmark;
130 break;
131#endif
132 case NFT_META_PKTTYPE:
133 if (skb->pkt_type != PACKET_LOOPBACK) {
134 *dest = skb->pkt_type;
135 break;
136 }
137
138 switch (pkt->ops->pf) {
139 case NFPROTO_IPV4:
140 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
141 *dest = PACKET_MULTICAST;
142 else
143 *dest = PACKET_BROADCAST;
144 break;
145 case NFPROTO_IPV6:
146 if (ipv6_hdr(skb)->daddr.s6_addr[0] == 0xFF)
147 *dest = PACKET_MULTICAST;
148 else
149 *dest = PACKET_BROADCAST;
150 break;
151 default:
152 WARN_ON(1);
153 goto err;
154 }
155 break;
156 case NFT_META_CPU:
157 *dest = raw_smp_processor_id();
158 break;
159 case NFT_META_IIFGROUP:
160 if (in == NULL)
161 goto err;
162 *dest = in->group;
163 break;
164 case NFT_META_OIFGROUP:
165 if (out == NULL)
166 goto err;
167 *dest = out->group;
168 break;
169 case NFT_META_CGROUP:
170 if (skb->sk == NULL || !sk_fullsock(skb->sk))
171 goto err;
172 *dest = skb->sk->sk_classid;
173 break;
174 default:
175 WARN_ON(1);
176 goto err;
177 }
178 return;
179
180err:
181 regs->verdict.code = NFT_BREAK;
182}
183EXPORT_SYMBOL_GPL(nft_meta_get_eval);
184
185void nft_meta_set_eval(const struct nft_expr *expr,
186 struct nft_regs *regs,
187 const struct nft_pktinfo *pkt)
188{
189 const struct nft_meta *meta = nft_expr_priv(expr);
190 struct sk_buff *skb = pkt->skb;
191 u32 value = regs->data[meta->sreg];
192
193 switch (meta->key) {
194 case NFT_META_MARK:
195 skb->mark = value;
196 break;
197 case NFT_META_PRIORITY:
198 skb->priority = value;
199 break;
200 case NFT_META_NFTRACE:
201 skb->nf_trace = 1;
202 break;
203 default:
204 WARN_ON(1);
205 }
206}
207EXPORT_SYMBOL_GPL(nft_meta_set_eval);
208
209const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = {
210 [NFTA_META_DREG] = { .type = NLA_U32 },
211 [NFTA_META_KEY] = { .type = NLA_U32 },
212 [NFTA_META_SREG] = { .type = NLA_U32 },
213};
214EXPORT_SYMBOL_GPL(nft_meta_policy);
215
216int nft_meta_get_init(const struct nft_ctx *ctx,
217 const struct nft_expr *expr,
218 const struct nlattr * const tb[])
219{
220 struct nft_meta *priv = nft_expr_priv(expr);
221 unsigned int len;
222
223 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
224 switch (priv->key) {
225 case NFT_META_PROTOCOL:
226 case NFT_META_IIFTYPE:
227 case NFT_META_OIFTYPE:
228 len = sizeof(u16);
229 break;
230 case NFT_META_NFPROTO:
231 case NFT_META_L4PROTO:
232 case NFT_META_LEN:
233 case NFT_META_PRIORITY:
234 case NFT_META_MARK:
235 case NFT_META_IIF:
236 case NFT_META_OIF:
237 case NFT_META_SKUID:
238 case NFT_META_SKGID:
239#ifdef CONFIG_IP_ROUTE_CLASSID
240 case NFT_META_RTCLASSID:
241#endif
242#ifdef CONFIG_NETWORK_SECMARK
243 case NFT_META_SECMARK:
244#endif
245 case NFT_META_PKTTYPE:
246 case NFT_META_CPU:
247 case NFT_META_IIFGROUP:
248 case NFT_META_OIFGROUP:
249 case NFT_META_CGROUP:
250 len = sizeof(u32);
251 break;
252 case NFT_META_IIFNAME:
253 case NFT_META_OIFNAME:
254 len = IFNAMSIZ;
255 break;
256 default:
257 return -EOPNOTSUPP;
258 }
259
260 priv->dreg = nft_parse_register(tb[NFTA_META_DREG]);
261 return nft_validate_register_store(ctx, priv->dreg, NULL,
262 NFT_DATA_VALUE, len);
263}
264EXPORT_SYMBOL_GPL(nft_meta_get_init);
265
266int nft_meta_set_init(const struct nft_ctx *ctx,
267 const struct nft_expr *expr,
268 const struct nlattr * const tb[])
269{
270 struct nft_meta *priv = nft_expr_priv(expr);
271 unsigned int len;
272 int err;
273
274 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
275 switch (priv->key) {
276 case NFT_META_MARK:
277 case NFT_META_PRIORITY:
278 len = sizeof(u32);
279 break;
280 case NFT_META_NFTRACE:
281 len = sizeof(u8);
282 break;
283 default:
284 return -EOPNOTSUPP;
285 }
286
287 priv->sreg = nft_parse_register(tb[NFTA_META_SREG]);
288 err = nft_validate_register_load(priv->sreg, len);
289 if (err < 0)
290 return err;
291
292 return 0;
293}
294EXPORT_SYMBOL_GPL(nft_meta_set_init);
295
296int nft_meta_get_dump(struct sk_buff *skb,
297 const struct nft_expr *expr)
298{
299 const struct nft_meta *priv = nft_expr_priv(expr);
300
301 if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
302 goto nla_put_failure;
303 if (nft_dump_register(skb, NFTA_META_DREG, priv->dreg))
304 goto nla_put_failure;
305 return 0;
306
307nla_put_failure:
308 return -1;
309}
310EXPORT_SYMBOL_GPL(nft_meta_get_dump);
311
312int nft_meta_set_dump(struct sk_buff *skb,
313 const struct nft_expr *expr)
314{
315 const struct nft_meta *priv = nft_expr_priv(expr);
316
317 if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
318 goto nla_put_failure;
319 if (nft_dump_register(skb, NFTA_META_SREG, priv->sreg))
320 goto nla_put_failure;
321
322 return 0;
323
324nla_put_failure:
325 return -1;
326}
327EXPORT_SYMBOL_GPL(nft_meta_set_dump);
328
329static struct nft_expr_type nft_meta_type;
330static const struct nft_expr_ops nft_meta_get_ops = {
331 .type = &nft_meta_type,
332 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
333 .eval = nft_meta_get_eval,
334 .init = nft_meta_get_init,
335 .dump = nft_meta_get_dump,
336};
337
338static const struct nft_expr_ops nft_meta_set_ops = {
339 .type = &nft_meta_type,
340 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
341 .eval = nft_meta_set_eval,
342 .init = nft_meta_set_init,
343 .dump = nft_meta_set_dump,
344};
345
346static const struct nft_expr_ops *
347nft_meta_select_ops(const struct nft_ctx *ctx,
348 const struct nlattr * const tb[])
349{
350 if (tb[NFTA_META_KEY] == NULL)
351 return ERR_PTR(-EINVAL);
352
353 if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
354 return ERR_PTR(-EINVAL);
355
356 if (tb[NFTA_META_DREG])
357 return &nft_meta_get_ops;
358
359 if (tb[NFTA_META_SREG])
360 return &nft_meta_set_ops;
361
362 return ERR_PTR(-EINVAL);
363}
364
365static struct nft_expr_type nft_meta_type __read_mostly = {
366 .name = "meta",
367 .select_ops = &nft_meta_select_ops,
368 .policy = nft_meta_policy,
369 .maxattr = NFTA_META_MAX,
370 .owner = THIS_MODULE,
371};
372
373static int __init nft_meta_module_init(void)
374{
375 return nft_register_expr(&nft_meta_type);
376}
377
378static void __exit nft_meta_module_exit(void)
379{
380 nft_unregister_expr(&nft_meta_type);
381}
382
383module_init(nft_meta_module_init);
384module_exit(nft_meta_module_exit);
385
386MODULE_LICENSE("GPL");
387MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
388MODULE_ALIAS_NFT_EXPR("meta");