LXR linux/net/ipv6/netfilter/nft_dup

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org>
   4 */
   5
   6#include <linux/kernel.h>
   7#include <linux/init.h>
   8#include <linux/module.h>
   9#include <linux/netlink.h>
  10#include <linux/netfilter.h>
  11#include <linux/netfilter/nf_tables.h>
  12#include <net/netfilter/nf_tables.h>
  13#include <net/netfilter/ipv6/nf_dup_ipv6.h>
  14
  15struct nft_dup_ipv6 {
  16        enum nft_registers      sreg_addr:8;
  17        enum nft_registers      sreg_dev:8;
  18};
  19
  20static void nft_dup_ipv6_eval(const struct nft_expr *expr,
  21                              struct nft_regs *regs,
  22                              const struct nft_pktinfo *pkt)
  23{
  24        struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
  25        struct in6_addr *gw = (struct in6_addr *)&regs->data[priv->sreg_addr];
  26        int oif = priv->sreg_dev ? regs->data[priv->sreg_dev] : -1;
  27
  28        nf_dup_ipv6(nft_net(pkt), pkt->skb, nft_hook(pkt), gw, oif);
  29}
  30
  31static int nft_dup_ipv6_init(const struct nft_ctx *ctx,
  32                             const struct nft_expr *expr,
  33                             const struct nlattr * const tb[])
  34{
  35        struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
  36        int err;
  37
  38        if (tb[NFTA_DUP_SREG_ADDR] == NULL)
  39                return -EINVAL;
  40
  41        priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]);
  42        err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in6_addr));
  43        if (err < 0)
  44                return err;
  45
  46        if (tb[NFTA_DUP_SREG_DEV] != NULL) {
  47                priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]);
  48                return nft_validate_register_load(priv->sreg_dev, sizeof(int));
  49        }
  50        return 0;
  51}
  52
  53static int nft_dup_ipv6_dump(struct sk_buff *skb, const struct nft_expr *expr)
  54{
  55        struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
  56
  57        if (nft_dump_register(skb, NFTA_DUP_SREG_ADDR, priv->sreg_addr))
  58                goto nla_put_failure;
  59        if (priv->sreg_dev &&
  60            nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev))
  61                goto nla_put_failure;
  62
  63        return 0;
  64
  65nla_put_failure:
  66        return -1;
  67}
  68
  69static struct nft_expr_type nft_dup_ipv6_type;
  70static const struct nft_expr_ops nft_dup_ipv6_ops = {
  71        .type           = &nft_dup_ipv6_type,
  72        .size           = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv6)),
  73        .eval           = nft_dup_ipv6_eval,
  74        .init           = nft_dup_ipv6_init,
  75        .dump           = nft_dup_ipv6_dump,
  76};
  77
  78static const struct nla_policy nft_dup_ipv6_policy[NFTA_DUP_MAX + 1] = {
  79        [NFTA_DUP_SREG_ADDR]    = { .type = NLA_U32 },
  80        [NFTA_DUP_SREG_DEV]     = { .type = NLA_U32 },
  81};
  82
  83static struct nft_expr_type nft_dup_ipv6_type __read_mostly = {
  84        .family         = NFPROTO_IPV6,
  85        .name           = "dup",
  86        .ops            = &nft_dup_ipv6_ops,
  87        .policy         = nft_dup_ipv6_policy,
  88        .maxattr        = NFTA_DUP_MAX,
  89        .owner          = THIS_MODULE,
  90};
  91
  92static int __init nft_dup_ipv6_module_init(void)
  93{
  94        return nft_register_expr(&nft_dup_ipv6_type);
  95}
  96
  97static void __exit nft_dup_ipv6_module_exit(void)
  98{
  99        nft_unregister_expr(&nft_dup_ipv6_type);
 100}
 101
 102module_init(nft_dup_ipv6_module_init);
 103module_exit(nft_dup_ipv6_module_exit);
 104
 105MODULE_LICENSE("GPL");
 106MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 107MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "dup");
 108MODULE_DESCRIPTION("IPv6 nftables packet duplication support");
 109