diff options
Diffstat (limited to 'net/netfilter/nft_nat.c')
| -rw-r--r-- | net/netfilter/nft_nat.c | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/net/netfilter/nft_nat.c b/net/netfilter/nft_nat.c new file mode 100644 index 000000000000..d3b1ffe26181 --- /dev/null +++ b/net/netfilter/nft_nat.c @@ -0,0 +1,224 @@ +/* + * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> + * Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org> + * Copyright (c) 2012 Intel Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/skbuff.h> +#include <linux/ip.h> +#include <linux/string.h> +#include <linux/netlink.h> +#include <linux/netfilter.h> +#include <linux/netfilter_ipv4.h> +#include <linux/netfilter/nfnetlink.h> +#include <linux/netfilter/nf_tables.h> +#include <net/netfilter/nf_conntrack.h> +#include <net/netfilter/nf_nat.h> +#include <net/netfilter/nf_nat_core.h> +#include <net/netfilter/nf_tables.h> +#include <net/netfilter/nf_nat_l3proto.h> +#include <net/ip.h> + +struct nft_nat { + enum nft_registers sreg_addr_min:8; + enum nft_registers sreg_addr_max:8; + enum nft_registers sreg_proto_min:8; + enum nft_registers sreg_proto_max:8; + int family; + enum nf_nat_manip_type type; +}; + +static void nft_nat_eval(const struct nft_expr *expr, + struct nft_data data[NFT_REG_MAX + 1], + const struct nft_pktinfo *pkt) +{ + const struct nft_nat *priv = nft_expr_priv(expr); + enum ip_conntrack_info ctinfo; + struct nf_conn *ct = nf_ct_get(pkt->skb, &ctinfo); + struct nf_nat_range range; + + memset(&range, 0, sizeof(range)); + if (priv->sreg_addr_min) { + if (priv->family == AF_INET) { + range.min_addr.ip = (__force __be32) + data[priv->sreg_addr_min].data[0]; + range.max_addr.ip = (__force __be32) + data[priv->sreg_addr_max].data[0]; + + } else { + memcpy(range.min_addr.ip6, + data[priv->sreg_addr_min].data, + sizeof(struct nft_data)); + memcpy(range.max_addr.ip6, + data[priv->sreg_addr_max].data, + sizeof(struct nft_data)); + } + range.flags |= NF_NAT_RANGE_MAP_IPS; + } + + if (priv->sreg_proto_min) { + range.min_proto.all = (__force __be16) + data[priv->sreg_proto_min].data[0]; + range.max_proto.all = (__force __be16) + data[priv->sreg_proto_max].data[0]; + range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; + } + + data[NFT_REG_VERDICT].verdict = + nf_nat_setup_info(ct, &range, priv->type); +} + +static const struct nla_policy nft_nat_policy[NFTA_NAT_MAX + 1] = { + [NFTA_NAT_TYPE] = { .type = NLA_U32 }, + [NFTA_NAT_FAMILY] = { .type = NLA_U32 }, + [NFTA_NAT_REG_ADDR_MIN] = { .type = NLA_U32 }, + [NFTA_NAT_REG_ADDR_MAX] = { .type = NLA_U32 }, + [NFTA_NAT_REG_PROTO_MIN] = { .type = NLA_U32 }, + [NFTA_NAT_REG_PROTO_MAX] = { .type = NLA_U32 }, +}; + +static int nft_nat_init(const struct nft_ctx *ctx, const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_nat *priv = nft_expr_priv(expr); + int err; + + if (tb[NFTA_NAT_TYPE] == NULL) + return -EINVAL; + + switch (ntohl(nla_get_be32(tb[NFTA_NAT_TYPE]))) { + case NFT_NAT_SNAT: + priv->type = NF_NAT_MANIP_SRC; + break; + case NFT_NAT_DNAT: + priv->type = NF_NAT_MANIP_DST; + break; + default: + return -EINVAL; + } + + if (tb[NFTA_NAT_FAMILY] == NULL) + return -EINVAL; + + priv->family = ntohl(nla_get_be32(tb[NFTA_NAT_FAMILY])); + if (priv->family != AF_INET && priv->family != AF_INET6) + return -EINVAL; + + if (tb[NFTA_NAT_REG_ADDR_MIN]) { + priv->sreg_addr_min = ntohl(nla_get_be32( + tb[NFTA_NAT_REG_ADDR_MIN])); + err = nft_validate_input_register(priv->sreg_addr_min); + if (err < 0) + return err; + } + + if (tb[NFTA_NAT_REG_ADDR_MAX]) { + priv->sreg_addr_max = ntohl(nla_get_be32( + tb[NFTA_NAT_REG_ADDR_MAX])); + err = nft_validate_input_register(priv->sreg_addr_max); + if (err < 0) + return err; + } else + priv->sreg_addr_max = priv->sreg_addr_min; + + if (tb[NFTA_NAT_REG_PROTO_MIN]) { + priv->sreg_proto_min = ntohl(nla_get_be32( + tb[NFTA_NAT_REG_PROTO_MIN])); + err = nft_validate_input_register(priv->sreg_proto_min); + if (err < 0) + return err; + } + + if (tb[NFTA_NAT_REG_PROTO_MAX]) { + priv->sreg_proto_max = ntohl(nla_get_be32( + tb[NFTA_NAT_REG_PROTO_MAX])); + err = nft_validate_input_register(priv->sreg_proto_max); + if (err < 0) + return err; + } else + priv->sreg_proto_max = priv->sreg_proto_min; + + return 0; +} + +static int nft_nat_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_nat *priv = nft_expr_priv(expr); + + switch (priv->type) { + case NF_NAT_MANIP_SRC: + if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_SNAT))) + goto nla_put_failure; + break; + case NF_NAT_MANIP_DST: + if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_DNAT))) + goto nla_put_failure; + break; + } + + if (nla_put_be32(skb, NFTA_NAT_FAMILY, htonl(priv->family))) + goto nla_put_failure; + if (nla_put_be32(skb, + NFTA_NAT_REG_ADDR_MIN, htonl(priv->sreg_addr_min))) + goto nla_put_failure; + if (nla_put_be32(skb, + NFTA_NAT_REG_ADDR_MAX, htonl(priv->sreg_addr_max))) + goto nla_put_failure; + if (nla_put_be32(skb, + NFTA_NAT_REG_PROTO_MIN, htonl(priv->sreg_proto_min))) + goto nla_put_failure; + if (nla_put_be32(skb, + NFTA_NAT_REG_PROTO_MAX, htonl(priv->sreg_proto_max))) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_nat_type; +static const struct nft_expr_ops nft_nat_ops = { + .type = &nft_nat_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_nat)), + .eval = nft_nat_eval, + .init = nft_nat_init, + .dump = nft_nat_dump, +}; + +static struct nft_expr_type nft_nat_type __read_mostly = { + .name = "nat", + .ops = &nft_nat_ops, + .policy = nft_nat_policy, + .maxattr = NFTA_NAT_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_nat_module_init(void) +{ + int err; + + err = nft_register_expr(&nft_nat_type); + if (err < 0) + return err; + + return 0; +} + +static void __exit nft_nat_module_exit(void) +{ + nft_unregister_expr(&nft_nat_type); +} + +module_init(nft_nat_module_init); +module_exit(nft_nat_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>"); +MODULE_ALIAS_NFT_EXPR("nat"); |