1 /*
2 * Copyright (c) 2014 Intel Corporation
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 */
9
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/netlink.h>
14 #include <linux/netfilter.h>
15 #include <linux/netfilter/nf_tables.h>
16 #include <net/netfilter/nf_tables.h>
17 #include <net/netfilter/nft_meta.h>
18
19 #include "../br_private.h"
20
nft_meta_bridge_get_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)21 static void nft_meta_bridge_get_eval(const struct nft_expr *expr,
22 struct nft_regs *regs,
23 const struct nft_pktinfo *pkt)
24 {
25 const struct nft_meta *priv = nft_expr_priv(expr);
26 const struct net_device *in = pkt->in, *out = pkt->out;
27 u32 *dest = ®s->data[priv->dreg];
28 const struct net_bridge_port *p;
29
30 switch (priv->key) {
31 case NFT_META_BRI_IIFNAME:
32 if (in == NULL || (p = br_port_get_rcu(in)) == NULL)
33 goto err;
34 break;
35 case NFT_META_BRI_OIFNAME:
36 if (out == NULL || (p = br_port_get_rcu(out)) == NULL)
37 goto err;
38 break;
39 default:
40 goto out;
41 }
42
43 strncpy((char *)dest, p->br->dev->name, IFNAMSIZ);
44 return;
45 out:
46 return nft_meta_get_eval(expr, regs, pkt);
47 err:
48 regs->verdict.code = NFT_BREAK;
49 }
50
nft_meta_bridge_get_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])51 static int nft_meta_bridge_get_init(const struct nft_ctx *ctx,
52 const struct nft_expr *expr,
53 const struct nlattr * const tb[])
54 {
55 struct nft_meta *priv = nft_expr_priv(expr);
56 unsigned int len;
57
58 priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
59 switch (priv->key) {
60 case NFT_META_BRI_IIFNAME:
61 case NFT_META_BRI_OIFNAME:
62 len = IFNAMSIZ;
63 break;
64 default:
65 return nft_meta_get_init(ctx, expr, tb);
66 }
67
68 priv->dreg = nft_parse_register(tb[NFTA_META_DREG]);
69 return nft_validate_register_store(ctx, priv->dreg, NULL,
70 NFT_DATA_VALUE, len);
71 }
72
73 static struct nft_expr_type nft_meta_bridge_type;
74 static const struct nft_expr_ops nft_meta_bridge_get_ops = {
75 .type = &nft_meta_bridge_type,
76 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
77 .eval = nft_meta_bridge_get_eval,
78 .init = nft_meta_bridge_get_init,
79 .dump = nft_meta_get_dump,
80 };
81
82 static const struct nft_expr_ops nft_meta_bridge_set_ops = {
83 .type = &nft_meta_bridge_type,
84 .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
85 .eval = nft_meta_set_eval,
86 .init = nft_meta_set_init,
87 .destroy = nft_meta_set_destroy,
88 .dump = nft_meta_set_dump,
89 .validate = nft_meta_set_validate,
90 };
91
92 static const struct nft_expr_ops *
nft_meta_bridge_select_ops(const struct nft_ctx * ctx,const struct nlattr * const tb[])93 nft_meta_bridge_select_ops(const struct nft_ctx *ctx,
94 const struct nlattr * const tb[])
95 {
96 if (tb[NFTA_META_KEY] == NULL)
97 return ERR_PTR(-EINVAL);
98
99 if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
100 return ERR_PTR(-EINVAL);
101
102 if (tb[NFTA_META_DREG])
103 return &nft_meta_bridge_get_ops;
104
105 if (tb[NFTA_META_SREG])
106 return &nft_meta_bridge_set_ops;
107
108 return ERR_PTR(-EINVAL);
109 }
110
111 static struct nft_expr_type nft_meta_bridge_type __read_mostly = {
112 .family = NFPROTO_BRIDGE,
113 .name = "meta",
114 .select_ops = &nft_meta_bridge_select_ops,
115 .policy = nft_meta_policy,
116 .maxattr = NFTA_META_MAX,
117 .owner = THIS_MODULE,
118 };
119
nft_meta_bridge_module_init(void)120 static int __init nft_meta_bridge_module_init(void)
121 {
122 return nft_register_expr(&nft_meta_bridge_type);
123 }
124
nft_meta_bridge_module_exit(void)125 static void __exit nft_meta_bridge_module_exit(void)
126 {
127 nft_unregister_expr(&nft_meta_bridge_type);
128 }
129
130 module_init(nft_meta_bridge_module_init);
131 module_exit(nft_meta_bridge_module_exit);
132
133 MODULE_LICENSE("GPL");
134 MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
135 MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "meta");
136