1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
4 * Copyright (c) 2013 Eric Leblond <eric@regit.org>
5 *
6 * Development of this code funded by Astaro AG (http://www.astaro.com/)
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/nft_reject.h>
17 #include <linux/icmp.h>
18 #include <linux/icmpv6.h>
19
20 const struct nla_policy nft_reject_policy[NFTA_REJECT_MAX + 1] = {
21 [NFTA_REJECT_TYPE] = { .type = NLA_U32 },
22 [NFTA_REJECT_ICMP_CODE] = { .type = NLA_U8 },
23 };
24 EXPORT_SYMBOL_GPL(nft_reject_policy);
25
nft_reject_validate(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nft_data ** data)26 int nft_reject_validate(const struct nft_ctx *ctx,
27 const struct nft_expr *expr,
28 const struct nft_data **data)
29 {
30 return nft_chain_validate_hooks(ctx->chain,
31 (1 << NF_INET_LOCAL_IN) |
32 (1 << NF_INET_FORWARD) |
33 (1 << NF_INET_LOCAL_OUT) |
34 (1 << NF_INET_PRE_ROUTING));
35 }
36 EXPORT_SYMBOL_GPL(nft_reject_validate);
37
nft_reject_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])38 int nft_reject_init(const struct nft_ctx *ctx,
39 const struct nft_expr *expr,
40 const struct nlattr * const tb[])
41 {
42 struct nft_reject *priv = nft_expr_priv(expr);
43
44 if (tb[NFTA_REJECT_TYPE] == NULL)
45 return -EINVAL;
46
47 priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE]));
48 switch (priv->type) {
49 case NFT_REJECT_ICMP_UNREACH:
50 if (tb[NFTA_REJECT_ICMP_CODE] == NULL)
51 return -EINVAL;
52 priv->icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]);
53 case NFT_REJECT_TCP_RST:
54 break;
55 default:
56 return -EINVAL;
57 }
58
59 return 0;
60 }
61 EXPORT_SYMBOL_GPL(nft_reject_init);
62
nft_reject_dump(struct sk_buff * skb,const struct nft_expr * expr)63 int nft_reject_dump(struct sk_buff *skb, const struct nft_expr *expr)
64 {
65 const struct nft_reject *priv = nft_expr_priv(expr);
66
67 if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type)))
68 goto nla_put_failure;
69
70 switch (priv->type) {
71 case NFT_REJECT_ICMP_UNREACH:
72 if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code))
73 goto nla_put_failure;
74 break;
75 default:
76 break;
77 }
78
79 return 0;
80
81 nla_put_failure:
82 return -1;
83 }
84 EXPORT_SYMBOL_GPL(nft_reject_dump);
85
86 static u8 icmp_code_v4[NFT_REJECT_ICMPX_MAX + 1] = {
87 [NFT_REJECT_ICMPX_NO_ROUTE] = ICMP_NET_UNREACH,
88 [NFT_REJECT_ICMPX_PORT_UNREACH] = ICMP_PORT_UNREACH,
89 [NFT_REJECT_ICMPX_HOST_UNREACH] = ICMP_HOST_UNREACH,
90 [NFT_REJECT_ICMPX_ADMIN_PROHIBITED] = ICMP_PKT_FILTERED,
91 };
92
nft_reject_icmp_code(u8 code)93 int nft_reject_icmp_code(u8 code)
94 {
95 if (WARN_ON_ONCE(code > NFT_REJECT_ICMPX_MAX))
96 return ICMP_NET_UNREACH;
97
98 return icmp_code_v4[code];
99 }
100
101 EXPORT_SYMBOL_GPL(nft_reject_icmp_code);
102
103
104 static u8 icmp_code_v6[NFT_REJECT_ICMPX_MAX + 1] = {
105 [NFT_REJECT_ICMPX_NO_ROUTE] = ICMPV6_NOROUTE,
106 [NFT_REJECT_ICMPX_PORT_UNREACH] = ICMPV6_PORT_UNREACH,
107 [NFT_REJECT_ICMPX_HOST_UNREACH] = ICMPV6_ADDR_UNREACH,
108 [NFT_REJECT_ICMPX_ADMIN_PROHIBITED] = ICMPV6_ADM_PROHIBITED,
109 };
110
nft_reject_icmpv6_code(u8 code)111 int nft_reject_icmpv6_code(u8 code)
112 {
113 if (WARN_ON_ONCE(code > NFT_REJECT_ICMPX_MAX))
114 return ICMPV6_NOROUTE;
115
116 return icmp_code_v6[code];
117 }
118
119 EXPORT_SYMBOL_GPL(nft_reject_icmpv6_code);
120
121 MODULE_LICENSE("GPL");
122 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
123 MODULE_DESCRIPTION("Netfilter x_tables over nftables module");
124