LXR linux/net/ipv4/netfilter/nft_redir

   1/*
   2 * Copyright (c) 2014 Arturo Borrero Gonzalez <arturo@debian.org>
   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/nf_nat.h>
  17#include <net/netfilter/nf_nat_redirect.h>
  18#include <net/netfilter/nft_redir.h>
  19
  20static void nft_redir_ipv4_eval(const struct nft_expr *expr,
  21                                struct nft_regs *regs,
  22                                const struct nft_pktinfo *pkt)
  23{
  24        struct nft_redir *priv = nft_expr_priv(expr);
  25        struct nf_nat_ipv4_multi_range_compat mr;
  26
  27        memset(&mr, 0, sizeof(mr));
  28        if (priv->sreg_proto_min) {
  29                mr.range[0].min.all = (__force __be16)nft_reg_load16(
  30                        &regs->data[priv->sreg_proto_min]);
  31                mr.range[0].max.all = (__force __be16)nft_reg_load16(
  32                        &regs->data[priv->sreg_proto_max]);
  33                mr.range[0].flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
  34        }
  35
  36        mr.range[0].flags |= priv->flags;
  37
  38        regs->verdict.code = nf_nat_redirect_ipv4(pkt->skb, &mr, nft_hook(pkt));
  39}
  40
  41static void
  42nft_redir_ipv4_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
  43{
  44        nf_ct_netns_put(ctx->net, NFPROTO_IPV4);
  45}
  46
  47static struct nft_expr_type nft_redir_ipv4_type;
  48static const struct nft_expr_ops nft_redir_ipv4_ops = {
  49        .type           = &nft_redir_ipv4_type,
  50        .size           = NFT_EXPR_SIZE(sizeof(struct nft_redir)),
  51        .eval           = nft_redir_ipv4_eval,
  52        .init           = nft_redir_init,
  53        .destroy        = nft_redir_ipv4_destroy,
  54        .dump           = nft_redir_dump,
  55        .validate       = nft_redir_validate,
  56};
  57
  58static struct nft_expr_type nft_redir_ipv4_type __read_mostly = {
  59        .family         = NFPROTO_IPV4,
  60        .name           = "redir",
  61        .ops            = &nft_redir_ipv4_ops,
  62        .policy         = nft_redir_policy,
  63        .maxattr        = NFTA_REDIR_MAX,
  64        .owner          = THIS_MODULE,
  65};
  66
  67static int __init nft_redir_ipv4_module_init(void)
  68{
  69        return nft_register_expr(&nft_redir_ipv4_type);
  70}
  71
  72static void __exit nft_redir_ipv4_module_exit(void)
  73{
  74        nft_unregister_expr(&nft_redir_ipv4_type);
  75}
  76
  77module_init(nft_redir_ipv4_module_init);
  78module_exit(nft_redir_ipv4_module_exit);
  79
  80MODULE_LICENSE("GPL");
  81MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");
  82MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "redir");
  83