LXR linux/net/netfilter/nft

   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
  20const 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};
  24EXPORT_SYMBOL_GPL(nft_reject_policy);
  25
  26int 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}
  36EXPORT_SYMBOL_GPL(nft_reject_validate);
  37
  38int 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        int icmp_code;
  44
  45        if (tb[NFTA_REJECT_TYPE] == NULL)
  46                return -EINVAL;
  47
  48        priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE]));
  49        switch (priv->type) {
  50        case NFT_REJECT_ICMP_UNREACH:
  51        case NFT_REJECT_ICMPX_UNREACH:
  52                if (tb[NFTA_REJECT_ICMP_CODE] == NULL)
  53                        return -EINVAL;
  54
  55                icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]);
  56                if (priv->type == NFT_REJECT_ICMPX_UNREACH &&
  57                    icmp_code > NFT_REJECT_ICMPX_MAX)
  58                        return -EINVAL;
  59
  60                priv->icmp_code = icmp_code;
  61                break;
  62        case NFT_REJECT_TCP_RST:
  63                break;
  64        default:
  65                return -EINVAL;
  66        }
  67
  68        return 0;
  69}
  70EXPORT_SYMBOL_GPL(nft_reject_init);
  71
  72int nft_reject_dump(struct sk_buff *skb, const struct nft_expr *expr)
  73{
  74        const struct nft_reject *priv = nft_expr_priv(expr);
  75
  76        if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type)))
  77                goto nla_put_failure;
  78
  79        switch (priv->type) {
  80        case NFT_REJECT_ICMP_UNREACH:
  81        case NFT_REJECT_ICMPX_UNREACH:
  82                if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code))
  83                        goto nla_put_failure;
  84                break;
  85        default:
  86                break;
  87        }
  88
  89        return 0;
  90
  91nla_put_failure:
  92        return -1;
  93}
  94EXPORT_SYMBOL_GPL(nft_reject_dump);
  95
  96static u8 icmp_code_v4[NFT_REJECT_ICMPX_MAX + 1] = {
  97        [NFT_REJECT_ICMPX_NO_ROUTE]             = ICMP_NET_UNREACH,
  98        [NFT_REJECT_ICMPX_PORT_UNREACH]         = ICMP_PORT_UNREACH,
  99        [NFT_REJECT_ICMPX_HOST_UNREACH]         = ICMP_HOST_UNREACH,
 100        [NFT_REJECT_ICMPX_ADMIN_PROHIBITED]     = ICMP_PKT_FILTERED,
 101};
 102
 103int nft_reject_icmp_code(u8 code)
 104{
 105        if (WARN_ON_ONCE(code > NFT_REJECT_ICMPX_MAX))
 106                return ICMP_NET_UNREACH;
 107
 108        return icmp_code_v4[code];
 109}
 110
 111EXPORT_SYMBOL_GPL(nft_reject_icmp_code);
 112
 113
 114static u8 icmp_code_v6[NFT_REJECT_ICMPX_MAX + 1] = {
 115        [NFT_REJECT_ICMPX_NO_ROUTE]             = ICMPV6_NOROUTE,
 116        [NFT_REJECT_ICMPX_PORT_UNREACH]         = ICMPV6_PORT_UNREACH,
 117        [NFT_REJECT_ICMPX_HOST_UNREACH]         = ICMPV6_ADDR_UNREACH,
 118        [NFT_REJECT_ICMPX_ADMIN_PROHIBITED]     = ICMPV6_ADM_PROHIBITED,
 119};
 120
 121int nft_reject_icmpv6_code(u8 code)
 122{
 123        if (WARN_ON_ONCE(code > NFT_REJECT_ICMPX_MAX))
 124                return ICMPV6_NOROUTE;
 125
 126        return icmp_code_v6[code];
 127}
 128
 129EXPORT_SYMBOL_GPL(nft_reject_icmpv6_code);
 130
 131MODULE_LICENSE("GPL");
 132MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 133MODULE_DESCRIPTION("Netfilter x_tables over nftables module");
 134