net/ipv6/netfilter/nft_redir_ipv6.c

   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/nft_redir.h>
  18 #include <net/netfilter/nf_nat_redirect.h>
  19
  20 static void nft_redir_ipv6_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_range range;
  26
  27         memset(&range, 0, sizeof(range));
  28         if (priv->sreg_proto_min) {
  29                 range.min_proto.all = (__force __be16)nft_reg_load16(
  30                         &regs->data[priv->sreg_proto_min]);
  31                 range.max_proto.all = (__force __be16)nft_reg_load16(
  32                         &regs->data[priv->sreg_proto_max]);
  33                 range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
  34         }
  35
  36         range.flags |= priv->flags;
  37
  38         regs->verdict.code =
  39                 nf_nat_redirect_ipv6(pkt->skb, &range, nft_hook(pkt));
  40 }
  41
  42 static void
  43 nft_redir_ipv6_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
  44 {
  45         nf_ct_netns_put(ctx->net, NFPROTO_IPV6);
  46 }
  47
  48 static struct nft_expr_type nft_redir_ipv6_type;
  49 static const struct nft_expr_ops nft_redir_ipv6_ops = {
  50         .type           = &nft_redir_ipv6_type,
  51         .size           = NFT_EXPR_SIZE(sizeof(struct nft_redir)),
  52         .eval           = nft_redir_ipv6_eval,
  53         .init           = nft_redir_init,
  54         .destroy        = nft_redir_ipv6_destroy,
  55         .dump           = nft_redir_dump,
  56         .validate       = nft_redir_validate,
  57 };
  58
  59 static struct nft_expr_type nft_redir_ipv6_type __read_mostly = {
  60         .family         = NFPROTO_IPV6,
  61         .name           = "redir",
  62         .ops            = &nft_redir_ipv6_ops,
  63         .policy         = nft_redir_policy,
  64         .maxattr        = NFTA_REDIR_MAX,
  65         .owner          = THIS_MODULE,
  66 };
  67
  68 static int __init nft_redir_ipv6_module_init(void)
  69 {
  70         return nft_register_expr(&nft_redir_ipv6_type);
  71 }
  72
  73 static void __exit nft_redir_ipv6_module_exit(void)
  74 {
  75         nft_unregister_expr(&nft_redir_ipv6_type);
  76 }
  77
  78 module_init(nft_redir_ipv6_module_init);
  79 module_exit(nft_redir_ipv6_module_exit);
  80
  81 MODULE_LICENSE("GPL");
  82 MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");
  83 MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "redir");