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_masq.h>
 18
 19const struct nla_policy nft_masq_policy[NFTA_MASQ_MAX + 1] = {
 20	[NFTA_MASQ_FLAGS]		= { .type = NLA_U32 },
 21	[NFTA_MASQ_REG_PROTO_MIN]	= { .type = NLA_U32 },
 22	[NFTA_MASQ_REG_PROTO_MAX]	= { .type = NLA_U32 },
 23};
 24EXPORT_SYMBOL_GPL(nft_masq_policy);
 25
 26int nft_masq_validate(const struct nft_ctx *ctx,
 27		      const struct nft_expr *expr,
 28		      const struct nft_data **data)
 29{
 30	int err;
 31
 32	err = nft_chain_validate_dependency(ctx->chain, NFT_CHAIN_T_NAT);
 33	if (err < 0)
 34		return err;
 35
 36	return nft_chain_validate_hooks(ctx->chain,
 37				        (1 << NF_INET_POST_ROUTING));
 38}
 39EXPORT_SYMBOL_GPL(nft_masq_validate);
 40
 41int nft_masq_init(const struct nft_ctx *ctx,
 42		  const struct nft_expr *expr,
 43		  const struct nlattr * const tb[])
 44{
 45	u32 plen = FIELD_SIZEOF(struct nf_nat_range, min_addr.all);
 46	struct nft_masq *priv = nft_expr_priv(expr);
 47	int err;
 48
 49	err = nft_masq_validate(ctx, expr, NULL);
 50	if (err)
 51		return err;
 52
 53	if (tb[NFTA_MASQ_FLAGS]) {
 54		priv->flags = ntohl(nla_get_be32(tb[NFTA_MASQ_FLAGS]));
 55		if (priv->flags & ~NF_NAT_RANGE_MASK)
 56			return -EINVAL;
 57	}
 58
 59	if (tb[NFTA_MASQ_REG_PROTO_MIN]) {
 60		priv->sreg_proto_min =
 61			nft_parse_register(tb[NFTA_MASQ_REG_PROTO_MIN]);
 62
 63		err = nft_validate_register_load(priv->sreg_proto_min, plen);
 64		if (err < 0)
 65			return err;
 66
 67		if (tb[NFTA_MASQ_REG_PROTO_MAX]) {
 68			priv->sreg_proto_max =
 69				nft_parse_register(tb[NFTA_MASQ_REG_PROTO_MAX]);
 70
 71			err = nft_validate_register_load(priv->sreg_proto_max,
 72							 plen);
 73			if (err < 0)
 74				return err;
 75		} else {
 76			priv->sreg_proto_max = priv->sreg_proto_min;
 77		}
 78	}
 79
 80	return nf_ct_netns_get(ctx->net, ctx->afi->family);
 81}
 82EXPORT_SYMBOL_GPL(nft_masq_init);
 83
 84int nft_masq_dump(struct sk_buff *skb, const struct nft_expr *expr)
 85{
 86	const struct nft_masq *priv = nft_expr_priv(expr);
 87
 88	if (priv->flags != 0 &&
 89	    nla_put_be32(skb, NFTA_MASQ_FLAGS, htonl(priv->flags)))
 90		goto nla_put_failure;
 91
 92	if (priv->sreg_proto_min) {
 93		if (nft_dump_register(skb, NFTA_MASQ_REG_PROTO_MIN,
 94				      priv->sreg_proto_min) ||
 95		    nft_dump_register(skb, NFTA_MASQ_REG_PROTO_MAX,
 96				      priv->sreg_proto_max))
 97			goto nla_put_failure;
 98	}
 99
100	return 0;
101
102nla_put_failure:
103	return -1;
104}
105EXPORT_SYMBOL_GPL(nft_masq_dump);
106
107MODULE_LICENSE("GPL");
108MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");