1 /*
2 * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 as published by
6 * the Free Software Foundation.
7 */
8
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.h>
16 #include <net/netfilter/ipv6/nf_dup_ipv6.h>
17
18 struct nft_dup_ipv6 {
19 enum nft_registers sreg_addr:8;
20 enum nft_registers sreg_dev:8;
21 };
22
nft_dup_ipv6_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)23 static void nft_dup_ipv6_eval(const struct nft_expr *expr,
24 struct nft_regs *regs,
25 const struct nft_pktinfo *pkt)
26 {
27 struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
28 struct in6_addr *gw = (struct in6_addr *)®s->data[priv->sreg_addr];
29 int oif = priv->sreg_dev ? regs->data[priv->sreg_dev] : -1;
30
31 nf_dup_ipv6(pkt->net, pkt->skb, pkt->hook, gw, oif);
32 }
33
nft_dup_ipv6_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])34 static int nft_dup_ipv6_init(const struct nft_ctx *ctx,
35 const struct nft_expr *expr,
36 const struct nlattr * const tb[])
37 {
38 struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
39 int err;
40
41 if (tb[NFTA_DUP_SREG_ADDR] == NULL)
42 return -EINVAL;
43
44 priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]);
45 err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in6_addr));
46 if (err < 0)
47 return err;
48
49 if (tb[NFTA_DUP_SREG_DEV] != NULL) {
50 priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]);
51 return nft_validate_register_load(priv->sreg_dev, sizeof(int));
52 }
53 return 0;
54 }
55
nft_dup_ipv6_dump(struct sk_buff * skb,const struct nft_expr * expr)56 static int nft_dup_ipv6_dump(struct sk_buff *skb, const struct nft_expr *expr)
57 {
58 struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
59
60 if (nft_dump_register(skb, NFTA_DUP_SREG_ADDR, priv->sreg_addr))
61 goto nla_put_failure;
62 if (priv->sreg_dev &&
63 nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev))
64 goto nla_put_failure;
65
66 return 0;
67
68 nla_put_failure:
69 return -1;
70 }
71
72 static struct nft_expr_type nft_dup_ipv6_type;
73 static const struct nft_expr_ops nft_dup_ipv6_ops = {
74 .type = &nft_dup_ipv6_type,
75 .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv6)),
76 .eval = nft_dup_ipv6_eval,
77 .init = nft_dup_ipv6_init,
78 .dump = nft_dup_ipv6_dump,
79 };
80
81 static const struct nla_policy nft_dup_ipv6_policy[NFTA_DUP_MAX + 1] = {
82 [NFTA_DUP_SREG_ADDR] = { .type = NLA_U32 },
83 [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 },
84 };
85
86 static struct nft_expr_type nft_dup_ipv6_type __read_mostly = {
87 .family = NFPROTO_IPV6,
88 .name = "dup",
89 .ops = &nft_dup_ipv6_ops,
90 .policy = nft_dup_ipv6_policy,
91 .maxattr = NFTA_DUP_MAX,
92 .owner = THIS_MODULE,
93 };
94
nft_dup_ipv6_module_init(void)95 static int __init nft_dup_ipv6_module_init(void)
96 {
97 return nft_register_expr(&nft_dup_ipv6_type);
98 }
99
nft_dup_ipv6_module_exit(void)100 static void __exit nft_dup_ipv6_module_exit(void)
101 {
102 nft_unregister_expr(&nft_dup_ipv6_type);
103 }
104
105 module_init(nft_dup_ipv6_module_init);
106 module_exit(nft_dup_ipv6_module_exit);
107
108 MODULE_LICENSE("GPL");
109 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
110 MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "dup");
111