Patrick McHardy | 05513e9 | 2014-02-05 15:03:39 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2014 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 | |
| 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> |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 17 | #include <net/netfilter/ipv4/nf_reject.h> |
| 18 | #include <net/netfilter/ipv6/nf_reject.h> |
Patrick McHardy | 05513e9 | 2014-02-05 15:03:39 +0000 | [diff] [blame] | 19 | |
| 20 | static void nft_reject_inet_eval(const struct nft_expr *expr, |
Patrick McHardy | a55e22e | 2015-04-11 02:27:31 +0100 | [diff] [blame] | 21 | struct nft_regs *regs, |
Patrick McHardy | 05513e9 | 2014-02-05 15:03:39 +0000 | [diff] [blame] | 22 | const struct nft_pktinfo *pkt) |
| 23 | { |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 24 | struct nft_reject *priv = nft_expr_priv(expr); |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 25 | |
Eric W. Biederman | 6aa187f | 2015-09-18 14:32:57 -0500 | [diff] [blame] | 26 | switch (pkt->pf) { |
Patrick McHardy | 05513e9 | 2014-02-05 15:03:39 +0000 | [diff] [blame] | 27 | case NFPROTO_IPV4: |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 28 | switch (priv->type) { |
| 29 | case NFT_REJECT_ICMP_UNREACH: |
Florian Westphal | ee586bb | 2015-02-16 18:54:04 +0100 | [diff] [blame] | 30 | nf_send_unreach(pkt->skb, priv->icmp_code, |
Eric W. Biederman | 6aa187f | 2015-09-18 14:32:57 -0500 | [diff] [blame] | 31 | pkt->hook); |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 32 | break; |
| 33 | case NFT_REJECT_TCP_RST: |
Eric W. Biederman | 372892e | 2015-09-25 15:07:27 -0500 | [diff] [blame] | 34 | nf_send_reset(pkt->net, pkt->skb, pkt->hook); |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 35 | break; |
| 36 | case NFT_REJECT_ICMPX_UNREACH: |
| 37 | nf_send_unreach(pkt->skb, |
Florian Westphal | ee586bb | 2015-02-16 18:54:04 +0100 | [diff] [blame] | 38 | nft_reject_icmp_code(priv->icmp_code), |
Eric W. Biederman | 6aa187f | 2015-09-18 14:32:57 -0500 | [diff] [blame] | 39 | pkt->hook); |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 40 | break; |
| 41 | } |
| 42 | break; |
Patrick McHardy | 05513e9 | 2014-02-05 15:03:39 +0000 | [diff] [blame] | 43 | case NFPROTO_IPV6: |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 44 | switch (priv->type) { |
| 45 | case NFT_REJECT_ICMP_UNREACH: |
Eric W. Biederman | 88182a0 | 2015-09-18 14:33:01 -0500 | [diff] [blame] | 46 | nf_send_unreach6(pkt->net, pkt->skb, priv->icmp_code, |
Eric W. Biederman | 6aa187f | 2015-09-18 14:32:57 -0500 | [diff] [blame] | 47 | pkt->hook); |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 48 | break; |
| 49 | case NFT_REJECT_TCP_RST: |
Eric W. Biederman | 88182a0 | 2015-09-18 14:33:01 -0500 | [diff] [blame] | 50 | nf_send_reset6(pkt->net, pkt->skb, pkt->hook); |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 51 | break; |
| 52 | case NFT_REJECT_ICMPX_UNREACH: |
Eric W. Biederman | 88182a0 | 2015-09-18 14:33:01 -0500 | [diff] [blame] | 53 | nf_send_unreach6(pkt->net, pkt->skb, |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 54 | nft_reject_icmpv6_code(priv->icmp_code), |
Eric W. Biederman | 6aa187f | 2015-09-18 14:32:57 -0500 | [diff] [blame] | 55 | pkt->hook); |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 56 | break; |
| 57 | } |
| 58 | break; |
Patrick McHardy | 05513e9 | 2014-02-05 15:03:39 +0000 | [diff] [blame] | 59 | } |
Patrick McHardy | a55e22e | 2015-04-11 02:27:31 +0100 | [diff] [blame] | 60 | |
| 61 | regs->verdict.code = NF_DROP; |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 62 | } |
| 63 | |
| 64 | static int nft_reject_inet_init(const struct nft_ctx *ctx, |
| 65 | const struct nft_expr *expr, |
| 66 | const struct nlattr * const tb[]) |
| 67 | { |
| 68 | struct nft_reject *priv = nft_expr_priv(expr); |
| 69 | int icmp_code; |
| 70 | |
| 71 | if (tb[NFTA_REJECT_TYPE] == NULL) |
| 72 | return -EINVAL; |
| 73 | |
| 74 | priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE])); |
| 75 | switch (priv->type) { |
| 76 | case NFT_REJECT_ICMP_UNREACH: |
| 77 | case NFT_REJECT_ICMPX_UNREACH: |
| 78 | if (tb[NFTA_REJECT_ICMP_CODE] == NULL) |
| 79 | return -EINVAL; |
| 80 | |
| 81 | icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]); |
| 82 | if (priv->type == NFT_REJECT_ICMPX_UNREACH && |
| 83 | icmp_code > NFT_REJECT_ICMPX_MAX) |
| 84 | return -EINVAL; |
| 85 | |
| 86 | priv->icmp_code = icmp_code; |
| 87 | break; |
| 88 | case NFT_REJECT_TCP_RST: |
| 89 | break; |
| 90 | default: |
| 91 | return -EINVAL; |
| 92 | } |
| 93 | return 0; |
| 94 | } |
| 95 | |
| 96 | static int nft_reject_inet_dump(struct sk_buff *skb, |
| 97 | const struct nft_expr *expr) |
| 98 | { |
| 99 | const struct nft_reject *priv = nft_expr_priv(expr); |
| 100 | |
| 101 | if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type))) |
| 102 | goto nla_put_failure; |
| 103 | |
| 104 | switch (priv->type) { |
| 105 | case NFT_REJECT_ICMP_UNREACH: |
| 106 | case NFT_REJECT_ICMPX_UNREACH: |
| 107 | if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code)) |
| 108 | goto nla_put_failure; |
| 109 | break; |
David S. Miller | 129d23a | 2015-04-27 13:20:34 -0400 | [diff] [blame] | 110 | default: |
| 111 | break; |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 112 | } |
| 113 | |
| 114 | return 0; |
| 115 | |
| 116 | nla_put_failure: |
| 117 | return -1; |
Patrick McHardy | 05513e9 | 2014-02-05 15:03:39 +0000 | [diff] [blame] | 118 | } |
| 119 | |
| 120 | static struct nft_expr_type nft_reject_inet_type; |
| 121 | static const struct nft_expr_ops nft_reject_inet_ops = { |
| 122 | .type = &nft_reject_inet_type, |
| 123 | .size = NFT_EXPR_SIZE(sizeof(struct nft_reject)), |
| 124 | .eval = nft_reject_inet_eval, |
Pablo Neira Ayuso | 51b0a5d | 2014-09-26 14:35:14 +0200 | [diff] [blame] | 125 | .init = nft_reject_inet_init, |
| 126 | .dump = nft_reject_inet_dump, |
Patrick McHardy | 05513e9 | 2014-02-05 15:03:39 +0000 | [diff] [blame] | 127 | }; |
| 128 | |
| 129 | static struct nft_expr_type nft_reject_inet_type __read_mostly = { |
| 130 | .family = NFPROTO_INET, |
| 131 | .name = "reject", |
| 132 | .ops = &nft_reject_inet_ops, |
| 133 | .policy = nft_reject_policy, |
| 134 | .maxattr = NFTA_REJECT_MAX, |
| 135 | .owner = THIS_MODULE, |
| 136 | }; |
| 137 | |
| 138 | static int __init nft_reject_inet_module_init(void) |
| 139 | { |
| 140 | return nft_register_expr(&nft_reject_inet_type); |
| 141 | } |
| 142 | |
| 143 | static void __exit nft_reject_inet_module_exit(void) |
| 144 | { |
| 145 | nft_unregister_expr(&nft_reject_inet_type); |
| 146 | } |
| 147 | |
| 148 | module_init(nft_reject_inet_module_init); |
| 149 | module_exit(nft_reject_inet_module_exit); |
| 150 | |
| 151 | MODULE_LICENSE("GPL"); |
| 152 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); |
| 153 | MODULE_ALIAS_NFT_AF_EXPR(1, "reject"); |