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9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/netlink.h>
13#include <linux/netfilter.h>
14#include <linux/netfilter/nf_tables.h>
15#include <net/netfilter/nf_tables_core.h>
16#include <net/netfilter/nf_tables.h>
17#include <net/netfilter/nft_fib.h>
18
19const struct nla_policy nft_fib_policy[NFTA_FIB_MAX + 1] = {
20 [NFTA_FIB_DREG] = { .type = NLA_U32 },
21 [NFTA_FIB_RESULT] = { .type = NLA_U32 },
22 [NFTA_FIB_FLAGS] = { .type = NLA_U32 },
23};
24EXPORT_SYMBOL(nft_fib_policy);
25
26#define NFTA_FIB_F_ALL (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR | \
27 NFTA_FIB_F_MARK | NFTA_FIB_F_IIF | NFTA_FIB_F_OIF | \
28 NFTA_FIB_F_PRESENT)
29
30int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr,
31 const struct nft_data **data)
32{
33 const struct nft_fib *priv = nft_expr_priv(expr);
34 unsigned int hooks;
35
36 switch (priv->result) {
37 case NFT_FIB_RESULT_OIF:
38 case NFT_FIB_RESULT_OIFNAME:
39 hooks = (1 << NF_INET_PRE_ROUTING);
40 break;
41 case NFT_FIB_RESULT_ADDRTYPE:
42 if (priv->flags & NFTA_FIB_F_IIF)
43 hooks = (1 << NF_INET_PRE_ROUTING) |
44 (1 << NF_INET_LOCAL_IN) |
45 (1 << NF_INET_FORWARD);
46 else if (priv->flags & NFTA_FIB_F_OIF)
47 hooks = (1 << NF_INET_LOCAL_OUT) |
48 (1 << NF_INET_POST_ROUTING) |
49 (1 << NF_INET_FORWARD);
50 else
51 hooks = (1 << NF_INET_LOCAL_IN) |
52 (1 << NF_INET_LOCAL_OUT) |
53 (1 << NF_INET_FORWARD) |
54 (1 << NF_INET_PRE_ROUTING) |
55 (1 << NF_INET_POST_ROUTING);
56
57 break;
58 default:
59 return -EINVAL;
60 }
61
62 return nft_chain_validate_hooks(ctx->chain, hooks);
63}
64EXPORT_SYMBOL_GPL(nft_fib_validate);
65
66int nft_fib_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
67 const struct nlattr * const tb[])
68{
69 struct nft_fib *priv = nft_expr_priv(expr);
70 unsigned int len;
71 int err;
72
73 if (!tb[NFTA_FIB_DREG] || !tb[NFTA_FIB_RESULT] || !tb[NFTA_FIB_FLAGS])
74 return -EINVAL;
75
76 priv->flags = ntohl(nla_get_be32(tb[NFTA_FIB_FLAGS]));
77
78 if (priv->flags == 0 || (priv->flags & ~NFTA_FIB_F_ALL))
79 return -EINVAL;
80
81 if ((priv->flags & (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR)) ==
82 (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR))
83 return -EINVAL;
84 if ((priv->flags & (NFTA_FIB_F_IIF | NFTA_FIB_F_OIF)) ==
85 (NFTA_FIB_F_IIF | NFTA_FIB_F_OIF))
86 return -EINVAL;
87 if ((priv->flags & (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR)) == 0)
88 return -EINVAL;
89
90 priv->result = ntohl(nla_get_be32(tb[NFTA_FIB_RESULT]));
91 priv->dreg = nft_parse_register(tb[NFTA_FIB_DREG]);
92
93 switch (priv->result) {
94 case NFT_FIB_RESULT_OIF:
95 if (priv->flags & NFTA_FIB_F_OIF)
96 return -EINVAL;
97 len = sizeof(int);
98 break;
99 case NFT_FIB_RESULT_OIFNAME:
100 if (priv->flags & NFTA_FIB_F_OIF)
101 return -EINVAL;
102 len = IFNAMSIZ;
103 break;
104 case NFT_FIB_RESULT_ADDRTYPE:
105 len = sizeof(u32);
106 break;
107 default:
108 return -EINVAL;
109 }
110
111 err = nft_validate_register_store(ctx, priv->dreg, NULL,
112 NFT_DATA_VALUE, len);
113 if (err < 0)
114 return err;
115
116 return 0;
117}
118EXPORT_SYMBOL_GPL(nft_fib_init);
119
120int nft_fib_dump(struct sk_buff *skb, const struct nft_expr *expr)
121{
122 const struct nft_fib *priv = nft_expr_priv(expr);
123
124 if (nft_dump_register(skb, NFTA_FIB_DREG, priv->dreg))
125 return -1;
126
127 if (nla_put_be32(skb, NFTA_FIB_RESULT, htonl(priv->result)))
128 return -1;
129
130 if (nla_put_be32(skb, NFTA_FIB_FLAGS, htonl(priv->flags)))
131 return -1;
132
133 return 0;
134}
135EXPORT_SYMBOL_GPL(nft_fib_dump);
136
137void nft_fib_store_result(void *reg, const struct nft_fib *priv,
138 const struct nft_pktinfo *pkt, int index)
139{
140 struct net_device *dev;
141 u32 *dreg = reg;
142
143 switch (priv->result) {
144 case NFT_FIB_RESULT_OIF:
145 *dreg = (priv->flags & NFTA_FIB_F_PRESENT) ? !!index : index;
146 break;
147 case NFT_FIB_RESULT_OIFNAME:
148 dev = dev_get_by_index_rcu(nft_net(pkt), index);
149 if (priv->flags & NFTA_FIB_F_PRESENT)
150 *dreg = !!dev;
151 else
152 strncpy(reg, dev ? dev->name : "", IFNAMSIZ);
153 break;
154 default:
155 WARN_ON_ONCE(1);
156 *dreg = 0;
157 break;
158 }
159}
160EXPORT_SYMBOL_GPL(nft_fib_store_result);
161
162MODULE_LICENSE("GPL");
163MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
164
