LXR linux/net/netfilter/nft_fwd

   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/nf_dup_netdev.h>
  17
  18struct nft_fwd_netdev {
  19        enum nft_registers      sreg_dev:8;
  20};
  21
  22static void nft_fwd_netdev_eval(const struct nft_expr *expr,
  23                                struct nft_regs *regs,
  24                                const struct nft_pktinfo *pkt)
  25{
  26        struct nft_fwd_netdev *priv = nft_expr_priv(expr);
  27        int oif = regs->data[priv->sreg_dev];
  28
  29        nf_fwd_netdev_egress(pkt, oif);
  30        regs->verdict.code = NF_STOLEN;
  31}
  32
  33static const struct nla_policy nft_fwd_netdev_policy[NFTA_FWD_MAX + 1] = {
  34        [NFTA_FWD_SREG_DEV]     = { .type = NLA_U32 },
  35};
  36
  37static int nft_fwd_netdev_init(const struct nft_ctx *ctx,
  38                               const struct nft_expr *expr,
  39                               const struct nlattr * const tb[])
  40{
  41        struct nft_fwd_netdev *priv = nft_expr_priv(expr);
  42
  43        if (tb[NFTA_FWD_SREG_DEV] == NULL)
  44                return -EINVAL;
  45
  46        priv->sreg_dev = nft_parse_register(tb[NFTA_FWD_SREG_DEV]);
  47        return nft_validate_register_load(priv->sreg_dev, sizeof(int));
  48}
  49
  50static const struct nft_expr_ops nft_fwd_netdev_ingress_ops;
  51
  52static int nft_fwd_netdev_dump(struct sk_buff *skb, const struct nft_expr *expr)
  53{
  54        struct nft_fwd_netdev *priv = nft_expr_priv(expr);
  55
  56        if (nft_dump_register(skb, NFTA_FWD_SREG_DEV, priv->sreg_dev))
  57                goto nla_put_failure;
  58
  59        return 0;
  60
  61nla_put_failure:
  62        return -1;
  63}
  64
  65static struct nft_expr_type nft_fwd_netdev_type;
  66static const struct nft_expr_ops nft_fwd_netdev_ops = {
  67        .type           = &nft_fwd_netdev_type,
  68        .size           = NFT_EXPR_SIZE(sizeof(struct nft_fwd_netdev)),
  69        .eval           = nft_fwd_netdev_eval,
  70        .init           = nft_fwd_netdev_init,
  71        .dump           = nft_fwd_netdev_dump,
  72};
  73
  74static struct nft_expr_type nft_fwd_netdev_type __read_mostly = {
  75        .family         = NFPROTO_NETDEV,
  76        .name           = "fwd",
  77        .ops            = &nft_fwd_netdev_ops,
  78        .policy         = nft_fwd_netdev_policy,
  79        .maxattr        = NFTA_FWD_MAX,
  80        .owner          = THIS_MODULE,
  81};
  82
  83static int __init nft_fwd_netdev_module_init(void)
  84{
  85        return nft_register_expr(&nft_fwd_netdev_type);
  86}
  87
  88static void __exit nft_fwd_netdev_module_exit(void)
  89{
  90        nft_unregister_expr(&nft_fwd_netdev_type);
  91}
  92
  93module_init(nft_fwd_netdev_module_init);
  94module_exit(nft_fwd_netdev_module_exit);
  95
  96MODULE_LICENSE("GPL");
  97MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
  98MODULE_ALIAS_NFT_AF_EXPR(5, "fwd");
  99