From eb31628e37a0a4e01fffd79dcc7f815d2357f53a Mon Sep 17 00:00:00 2001 From: Tomasz Bursztyka Date: Thu, 10 Oct 2013 13:39:19 +0200 Subject: [PATCH] netfilter: nf_tables: Add support for IPv6 NAT This patch generalizes the NAT expression to support both IPv4 and IPv6 using the existing IPv4/IPv6 NAT infrastructure. This also adds the NAT chain type for IPv6. This patch collapses the following patches that were posted to the netfilter-devel mailing list, from Tomasz: * nf_tables: Change NFTA_NAT_ attributes to better semantic significance * nf_tables: Split IPv4 NAT into NAT expression and IPv4 NAT chain * nf_tables: Add support for IPv6 NAT expression * nf_tables: Add support for IPv6 NAT chain * nf_tables: Fix up build issue on IPv6 NAT support And, from Pablo Neira Ayuso: * fix missing dependencies in nft_chain_nat Signed-off-by: Tomasz Bursztyka Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_tables.h | 18 +- net/ipv4/netfilter/Kconfig | 1 + net/ipv4/netfilter/nft_chain_nat_ipv4.c | 156 +--------------- net/ipv6/netfilter/Kconfig | 5 + net/ipv6/netfilter/Makefile | 1 + net/ipv6/netfilter/nft_chain_nat_ipv6.c | 211 ++++++++++++++++++++++ net/netfilter/Kconfig | 6 + net/netfilter/Makefile | 1 + net/netfilter/nft_nat.c | 220 +++++++++++++++++++++++ 9 files changed, 457 insertions(+), 162 deletions(-) create mode 100644 net/ipv6/netfilter/nft_chain_nat_ipv6.c create mode 100644 net/netfilter/nft_nat.c diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index a9c4bce1988f..7d4a1992f89c 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -695,18 +695,20 @@ enum nft_nat_types { * enum nft_nat_attributes - nf_tables nat expression netlink attributes * * @NFTA_NAT_TYPE: NAT type (NLA_U32: nft_nat_types) - * @NFTA_NAT_ADDR_MIN: source register of address range start (NLA_U32: nft_registers) - * @NFTA_NAT_ADDR_MAX: source register of address range end (NLA_U32: nft_registers) - * @NFTA_NAT_PROTO_MIN: source register of proto range start (NLA_U32: nft_registers) - * @NFTA_NAT_PROTO_MAX: source register of proto range end (NLA_U32: nft_registers) + * @NFTA_NAT_FAMILY: NAT family (NLA_U32) + * @NFTA_NAT_REG_ADDR_MIN: source register of address range start (NLA_U32: nft_registers) + * @NFTA_NAT_REG_ADDR_MAX: source register of address range end (NLA_U32: nft_registers) + * @NFTA_NAT_REG_PROTO_MIN: source register of proto range start (NLA_U32: nft_registers) + * @NFTA_NAT_REG_PROTO_MAX: source register of proto range end (NLA_U32: nft_registers) */ enum nft_nat_attributes { NFTA_NAT_UNSPEC, NFTA_NAT_TYPE, - NFTA_NAT_ADDR_MIN, - NFTA_NAT_ADDR_MAX, - NFTA_NAT_PROTO_MIN, - NFTA_NAT_PROTO_MAX, + NFTA_NAT_FAMILY, + NFTA_NAT_REG_ADDR_MIN, + NFTA_NAT_REG_ADDR_MAX, + NFTA_NAT_REG_PROTO_MIN, + NFTA_NAT_REG_PROTO_MAX, __NFTA_NAT_MAX }; #define NFTA_NAT_MAX (__NFTA_NAT_MAX - 1) diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig index ae65fe98bfbe..1f37ef67f1ac 100644 --- a/net/ipv4/netfilter/Kconfig +++ b/net/ipv4/netfilter/Kconfig @@ -50,6 +50,7 @@ config NFT_CHAIN_ROUTE_IPV4 config NFT_CHAIN_NAT_IPV4 depends on NF_TABLES_IPV4 + depends on NF_NAT_IPV4 && NFT_NAT tristate "IPv4 nf_tables nat chain support" config IP_NF_IPTABLES diff --git a/net/ipv4/netfilter/nft_chain_nat_ipv4.c b/net/ipv4/netfilter/nft_chain_nat_ipv4.c index e09c201adf84..cf2c792cd971 100644 --- a/net/ipv4/netfilter/nft_chain_nat_ipv4.c +++ b/net/ipv4/netfilter/nft_chain_nat_ipv4.c @@ -1,6 +1,7 @@ /* * Copyright (c) 2008-2009 Patrick McHardy * Copyright (c) 2012 Pablo Neira Ayuso + * Copyright (c) 2012 Intel Corporation * * 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 @@ -14,10 +15,8 @@ #include #include #include -#include #include #include -#include #include #include #include @@ -27,147 +26,6 @@ #include #include -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; - 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) { - range.min_addr.ip = data[priv->sreg_addr_min].data[0]; - range.max_addr.ip = data[priv->sreg_addr_max].data[0]; - range.flags |= NF_NAT_RANGE_MAP_IPS; - } - - if (priv->sreg_proto_min) { - range.min_proto.all = data[priv->sreg_proto_min].data[0]; - range.max_proto.all = 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_ADDR_MIN] = { .type = NLA_U32 }, - [NFTA_NAT_ADDR_MAX] = { .type = NLA_U32 }, - [NFTA_NAT_PROTO_MIN] = { .type = NLA_U32 }, - [NFTA_NAT_PROTO_MAX] = { .type = NLA_U32 }, - [NFTA_NAT_TYPE] = { .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_ADDR_MIN]) { - priv->sreg_addr_min = ntohl(nla_get_be32(tb[NFTA_NAT_ADDR_MIN])); - err = nft_validate_input_register(priv->sreg_addr_min); - if (err < 0) - return err; - } - - if (tb[NFTA_NAT_ADDR_MAX]) { - priv->sreg_addr_max = ntohl(nla_get_be32(tb[NFTA_NAT_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_PROTO_MIN]) { - priv->sreg_proto_min = ntohl(nla_get_be32(tb[NFTA_NAT_PROTO_MIN])); - err = nft_validate_input_register(priv->sreg_proto_min); - if (err < 0) - return err; - } - - if (tb[NFTA_NAT_PROTO_MAX]) { - priv->sreg_proto_max = ntohl(nla_get_be32(tb[NFTA_NAT_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_ADDR_MIN, htonl(priv->sreg_addr_min))) - goto nla_put_failure; - if (nla_put_be32(skb, NFTA_NAT_ADDR_MAX, htonl(priv->sreg_addr_max))) - goto nla_put_failure; - if (nla_put_be32(skb, NFTA_NAT_PROTO_MIN, htonl(priv->sreg_proto_min))) - goto nla_put_failure; - if (nla_put_be32(skb, NFTA_NAT_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, -}; - /* * NAT chains */ @@ -306,7 +164,7 @@ static unsigned int nf_nat_output(const struct nf_hook_ops *ops, return ret; } -struct nf_chain_type nft_chain_nat_ipv4 = { +static struct nf_chain_type nft_chain_nat_ipv4 = { .family = NFPROTO_IPV4, .name = "nat", .type = NFT_CHAIN_T_NAT, @@ -331,20 +189,11 @@ static int __init nft_chain_nat_init(void) if (err < 0) return err; - err = nft_register_expr(&nft_nat_type); - if (err < 0) - goto err; - return 0; - -err: - nft_unregister_chain_type(&nft_chain_nat_ipv4); - return err; } static void __exit nft_chain_nat_exit(void) { - nft_unregister_expr(&nft_nat_type); nft_unregister_chain_type(&nft_chain_nat_ipv4); } @@ -354,4 +203,3 @@ module_exit(nft_chain_nat_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Patrick McHardy "); MODULE_ALIAS_NFT_CHAIN(AF_INET, "nat"); -MODULE_ALIAS_NFT_EXPR("nat"); diff --git a/net/ipv6/netfilter/Kconfig b/net/ipv6/netfilter/Kconfig index 23833064b7b5..7702f9e90a04 100644 --- a/net/ipv6/netfilter/Kconfig +++ b/net/ipv6/netfilter/Kconfig @@ -33,6 +33,11 @@ config NFT_CHAIN_ROUTE_IPV6 depends on NF_TABLES_IPV6 tristate "IPv6 nf_tables route chain support" +config NFT_CHAIN_NAT_IPV6 + depends on NF_TABLES_IPV6 + depends on NF_NAT_IPV6 && NFT_NAT + tristate "IPv6 nf_tables nat chain support" + config IP6_NF_IPTABLES tristate "IP6 tables support (required for filtering)" depends on INET && IPV6 diff --git a/net/ipv6/netfilter/Makefile b/net/ipv6/netfilter/Makefile index be4913aa524d..d1b4928f34f7 100644 --- a/net/ipv6/netfilter/Makefile +++ b/net/ipv6/netfilter/Makefile @@ -26,6 +26,7 @@ obj-$(CONFIG_NF_DEFRAG_IPV6) += nf_defrag_ipv6.o # nf_tables obj-$(CONFIG_NF_TABLES_IPV6) += nf_tables_ipv6.o obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV6) += nft_chain_route_ipv6.o +obj-$(CONFIG_NFT_CHAIN_NAT_IPV6) += nft_chain_nat_ipv6.o # matches obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o diff --git a/net/ipv6/netfilter/nft_chain_nat_ipv6.c b/net/ipv6/netfilter/nft_chain_nat_ipv6.c new file mode 100644 index 000000000000..e86dcd70dc76 --- /dev/null +++ b/net/ipv6/netfilter/nft_chain_nat_ipv6.c @@ -0,0 +1,211 @@ +/* + * Copyright (c) 2011 Patrick McHardy + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * IPv6 NAT chains + */ + +static unsigned int nf_nat_ipv6_fn(const struct nf_hook_ops *ops, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + enum ip_conntrack_info ctinfo; + struct nf_conn *ct = nf_ct_get(skb, &ctinfo); + struct nf_conn_nat *nat; + enum nf_nat_manip_type maniptype = HOOK2MANIP(ops->hooknum); + __be16 frag_off; + int hdrlen; + u8 nexthdr; + struct nft_pktinfo pkt; + unsigned int ret; + + if (ct == NULL || nf_ct_is_untracked(ct)) + return NF_ACCEPT; + + nat = nfct_nat(ct); + if (nat == NULL) { + /* Conntrack module was loaded late, can't add extension. */ + if (nf_ct_is_confirmed(ct)) + return NF_ACCEPT; + nat = nf_ct_ext_add(ct, NF_CT_EXT_NAT, GFP_ATOMIC); + if (nat == NULL) + return NF_ACCEPT; + } + + switch (ctinfo) { + case IP_CT_RELATED: + case IP_CT_RELATED + IP_CT_IS_REPLY: + nexthdr = ipv6_hdr(skb)->nexthdr; + hdrlen = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), + &nexthdr, &frag_off); + + if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { + if (!nf_nat_icmpv6_reply_translation(skb, ct, ctinfo, + ops->hooknum, + hdrlen)) + return NF_DROP; + else + return NF_ACCEPT; + } + /* Fall through */ + case IP_CT_NEW: + if (nf_nat_initialized(ct, maniptype)) + break; + + nft_set_pktinfo_ipv6(&pkt, ops, skb, in, out); + + ret = nft_do_chain_pktinfo(&pkt, ops); + if (ret != NF_ACCEPT) + return ret; + if (!nf_nat_initialized(ct, maniptype)) { + ret = nf_nat_alloc_null_binding(ct, ops->hooknum); + if (ret != NF_ACCEPT) + return ret; + } + default: + break; + } + + return nf_nat_packet(ct, ctinfo, ops->hooknum, skb); +} + +static unsigned int nf_nat_ipv6_prerouting(const struct nf_hook_ops *ops, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + struct in6_addr daddr = ipv6_hdr(skb)->daddr; + unsigned int ret; + + ret = nf_nat_ipv6_fn(ops, skb, in, out, okfn); + if (ret != NF_DROP && ret != NF_STOLEN && + ipv6_addr_cmp(&daddr, &ipv6_hdr(skb)->daddr)) + skb_dst_drop(skb); + + return ret; +} + +static unsigned int nf_nat_ipv6_postrouting(const struct nf_hook_ops *ops, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + enum ip_conntrack_info ctinfo __maybe_unused; + const struct nf_conn *ct __maybe_unused; + unsigned int ret; + + ret = nf_nat_ipv6_fn(ops, skb, in, out, okfn); +#ifdef CONFIG_XFRM + if (ret != NF_DROP && ret != NF_STOLEN && + !(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && + (ct = nf_ct_get(skb, &ctinfo)) != NULL) { + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + + if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3) || + (ct->tuplehash[dir].tuple.src.u.all != + ct->tuplehash[!dir].tuple.dst.u.all)) + if (nf_xfrm_me_harder(skb, AF_INET6) < 0) + ret = NF_DROP; + } +#endif + return ret; +} + +static unsigned int nf_nat_ipv6_output(const struct nf_hook_ops *ops, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + enum ip_conntrack_info ctinfo; + const struct nf_conn *ct; + unsigned int ret; + + ret = nf_nat_ipv6_fn(ops, skb, in, out, okfn); + if (ret != NF_DROP && ret != NF_STOLEN && + (ct = nf_ct_get(skb, &ctinfo)) != NULL) { + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + + if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3, + &ct->tuplehash[!dir].tuple.src.u3)) { + if (ip6_route_me_harder(skb)) + ret = NF_DROP; + } +#ifdef CONFIG_XFRM + else if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && + ct->tuplehash[dir].tuple.dst.u.all != + ct->tuplehash[!dir].tuple.src.u.all) + if (nf_xfrm_me_harder(skb, AF_INET6)) + ret = NF_DROP; +#endif + } + return ret; +} + +static struct nf_chain_type nft_chain_nat_ipv6 = { + .family = NFPROTO_IPV6, + .name = "nat", + .type = NFT_CHAIN_T_NAT, + .hook_mask = (1 << NF_INET_PRE_ROUTING) | + (1 << NF_INET_POST_ROUTING) | + (1 << NF_INET_LOCAL_OUT) | + (1 << NF_INET_LOCAL_IN), + .fn = { + [NF_INET_PRE_ROUTING] = nf_nat_ipv6_prerouting, + [NF_INET_POST_ROUTING] = nf_nat_ipv6_postrouting, + [NF_INET_LOCAL_OUT] = nf_nat_ipv6_output, + [NF_INET_LOCAL_IN] = nf_nat_ipv6_fn, + }, + .me = THIS_MODULE, +}; + +static int __init nft_chain_nat_ipv6_init(void) +{ + int err; + + err = nft_register_chain_type(&nft_chain_nat_ipv6); + if (err < 0) + return err; + + return 0; +} + +static void __exit nft_chain_nat_ipv6_exit(void) +{ + nft_unregister_chain_type(&nft_chain_nat_ipv6); +} + +module_init(nft_chain_nat_ipv6_init); +module_exit(nft_chain_nat_ipv6_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Tomasz Bursztyka "); +MODULE_ALIAS_NFT_CHAIN(AF_INET6, "nat"); diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index 49e362707379..48acec17e27a 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -450,6 +450,12 @@ config NFT_LIMIT depends on NF_TABLES tristate "Netfilter nf_tables limit module" +config NFT_NAT + depends on NF_TABLES + depends on NF_CONNTRACK + depends on NF_NAT + tristate "Netfilter nf_tables nat module" + config NFT_COMPAT depends on NF_TABLES depends on NETFILTER_XTABLES diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index a6781450b6fb..394483b2c193 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -75,6 +75,7 @@ obj-$(CONFIG_NFT_EXTHDR) += nft_exthdr.o obj-$(CONFIG_NFT_META) += nft_meta.o obj-$(CONFIG_NFT_CT) += nft_ct.o obj-$(CONFIG_NFT_LIMIT) += nft_limit.o +obj-$(CONFIG_NFT_NAT) += nft_nat.o #nf_tables-objs += nft_meta_target.o obj-$(CONFIG_NFT_RBTREE) += nft_rbtree.o obj-$(CONFIG_NFT_HASH) += nft_hash.o diff --git a/net/netfilter/nft_nat.c b/net/netfilter/nft_nat.c new file mode 100644 index 000000000000..b0b87b2d2411 --- /dev/null +++ b/net/netfilter/nft_nat.c @@ -0,0 +1,220 @@ +/* + * Copyright (c) 2008-2009 Patrick McHardy + * Copyright (c) 2012 Pablo Neira Ayuso + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +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 = data[priv->sreg_addr_min].data[0]; + range.max_addr.ip = 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 = data[priv->sreg_proto_min].data[0]; + range.max_proto.all = 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 "); +MODULE_ALIAS_NFT_EXPR("nat");