| /* |
| * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org> |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 as published by |
| * the Free Software Foundation. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/netlink.h> |
| #include <linux/netfilter.h> |
| #include <linux/netfilter/nf_tables.h> |
| #include <net/netfilter/nf_tables.h> |
| #include <net/netfilter/ipv4/nf_dup_ipv4.h> |
| |
| struct nft_dup_ipv4 { |
| enum nft_registers sreg_addr:8; |
| enum nft_registers sreg_dev:8; |
| }; |
| |
| static void nft_dup_ipv4_eval(const struct nft_expr *expr, |
| struct nft_regs *regs, |
| const struct nft_pktinfo *pkt) |
| { |
| struct nft_dup_ipv4 *priv = nft_expr_priv(expr); |
| struct in_addr gw = { |
| .s_addr = (__force __be32)regs->data[priv->sreg_addr], |
| }; |
| int oif = priv->sreg_dev ? regs->data[priv->sreg_dev] : -1; |
| |
| nf_dup_ipv4(nft_net(pkt), pkt->skb, nft_hook(pkt), &gw, oif); |
| } |
| |
| static int nft_dup_ipv4_init(const struct nft_ctx *ctx, |
| const struct nft_expr *expr, |
| const struct nlattr * const tb[]) |
| { |
| struct nft_dup_ipv4 *priv = nft_expr_priv(expr); |
| int err; |
| |
| if (tb[NFTA_DUP_SREG_ADDR] == NULL) |
| return -EINVAL; |
| |
| priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]); |
| err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in_addr)); |
| if (err < 0) |
| return err; |
| |
| if (tb[NFTA_DUP_SREG_DEV] != NULL) { |
| priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]); |
| return nft_validate_register_load(priv->sreg_dev, sizeof(int)); |
| } |
| return 0; |
| } |
| |
| static int nft_dup_ipv4_dump(struct sk_buff *skb, const struct nft_expr *expr) |
| { |
| struct nft_dup_ipv4 *priv = nft_expr_priv(expr); |
| |
| if (nft_dump_register(skb, NFTA_DUP_SREG_ADDR, priv->sreg_addr)) |
| goto nla_put_failure; |
| if (priv->sreg_dev && |
| nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev)) |
| goto nla_put_failure; |
| |
| return 0; |
| |
| nla_put_failure: |
| return -1; |
| } |
| |
| static struct nft_expr_type nft_dup_ipv4_type; |
| static const struct nft_expr_ops nft_dup_ipv4_ops = { |
| .type = &nft_dup_ipv4_type, |
| .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv4)), |
| .eval = nft_dup_ipv4_eval, |
| .init = nft_dup_ipv4_init, |
| .dump = nft_dup_ipv4_dump, |
| }; |
| |
| static const struct nla_policy nft_dup_ipv4_policy[NFTA_DUP_MAX + 1] = { |
| [NFTA_DUP_SREG_ADDR] = { .type = NLA_U32 }, |
| [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 }, |
| }; |
| |
| static struct nft_expr_type nft_dup_ipv4_type __read_mostly = { |
| .family = NFPROTO_IPV4, |
| .name = "dup", |
| .ops = &nft_dup_ipv4_ops, |
| .policy = nft_dup_ipv4_policy, |
| .maxattr = NFTA_DUP_MAX, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int __init nft_dup_ipv4_module_init(void) |
| { |
| return nft_register_expr(&nft_dup_ipv4_type); |
| } |
| |
| static void __exit nft_dup_ipv4_module_exit(void) |
| { |
| nft_unregister_expr(&nft_dup_ipv4_type); |
| } |
| |
| module_init(nft_dup_ipv4_module_init); |
| module_exit(nft_dup_ipv4_module_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>"); |
| MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "dup"); |