From 9ba1f726bec090399eb9bb9157eb32dedc8e8c45 Mon Sep 17 00:00:00 2001 From: Arturo Borrero Date: Mon, 8 Sep 2014 13:45:00 +0200 Subject: [PATCH] netfilter: nf_tables: add new nft_masq expression The nft_masq expression is intended to perform NAT in the masquerade flavour. We decided to have the masquerade functionality in a separated expression other than nft_nat. Signed-off-by: Arturo Borrero Gonzalez Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nft_masq.h | 16 ++++++ include/uapi/linux/netfilter/nf_tables.h | 11 ++++ net/ipv4/netfilter/Kconfig | 6 +++ net/ipv4/netfilter/Makefile | 1 + net/ipv4/netfilter/nft_masq_ipv4.c | 89 ++++++++++++++++++++++++++++++++ net/ipv6/netfilter/Kconfig | 6 +++ net/ipv6/netfilter/Makefile | 1 + net/ipv6/netfilter/nft_masq_ipv6.c | 89 ++++++++++++++++++++++++++++++++ net/netfilter/Kconfig | 9 ++++ net/netfilter/Makefile | 1 + net/netfilter/nft_masq.c | 59 +++++++++++++++++++++ 11 files changed, 288 insertions(+) create mode 100644 include/net/netfilter/nft_masq.h create mode 100644 net/ipv4/netfilter/nft_masq_ipv4.c create mode 100644 net/ipv6/netfilter/nft_masq_ipv6.c create mode 100644 net/netfilter/nft_masq.c diff --git a/include/net/netfilter/nft_masq.h b/include/net/netfilter/nft_masq.h new file mode 100644 index 0000000..c72729f --- /dev/null +++ b/include/net/netfilter/nft_masq.h @@ -0,0 +1,16 @@ +#ifndef _NFT_MASQ_H_ +#define _NFT_MASQ_H_ + +struct nft_masq { + u32 flags; +}; + +extern const struct nla_policy nft_masq_policy[]; + +int nft_masq_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]); + +int nft_masq_dump(struct sk_buff *skb, const struct nft_expr *expr); + +#endif /* _NFT_MASQ_H_ */ diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 6022c6e..eeec0ae 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -800,4 +800,15 @@ enum nft_nat_attributes { }; #define NFTA_NAT_MAX (__NFTA_NAT_MAX - 1) +/** + * enum nft_masq_attributes - nf_tables masquerade expression attributes + * + * @NFTA_MASQ_FLAGS: NAT flags (see NF_NAT_RANGE_* in linux/netfilter/nf_nat.h) (NLA_U32) + */ +enum nft_masq_attributes { + NFTA_MASQ_FLAGS, + __NFTA_MASQ_MAX +}; +#define NFTA_MASQ_MAX (__NFTA_MASQ_MAX - 1) + #endif /* _LINUX_NF_TABLES_H */ diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig index 4be3e54..8dd3d9f 100644 --- a/net/ipv4/netfilter/Kconfig +++ b/net/ipv4/netfilter/Kconfig @@ -190,6 +190,12 @@ config NF_NAT_MASQUERADE_IPV4 This is the kernel functionality to provide NAT in the masquerade flavour (automatic source address selection). +config NFT_MASQ_IPV4 + tristate "IPv4 masquerading support for nf_tables" + depends on NF_TABLES_IPV4 + depends on NFT_MASQ + select NF_NAT_MASQUERADE_IPV4 + config IP_NF_TARGET_MASQUERADE tristate "MASQUERADE target support" select NF_NAT_MASQUERADE_IPV4 diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile index 42056b2..7d019ae 100644 --- a/net/ipv4/netfilter/Makefile +++ b/net/ipv4/netfilter/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_NF_TABLES_IPV4) += nf_tables_ipv4.o obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV4) += nft_chain_route_ipv4.o obj-$(CONFIG_NFT_CHAIN_NAT_IPV4) += nft_chain_nat_ipv4.o obj-$(CONFIG_NFT_REJECT_IPV4) += nft_reject_ipv4.o +obj-$(CONFIG_NFT_MASQ_IPV4) += nft_masq_ipv4.o obj-$(CONFIG_NF_TABLES_ARP) += nf_tables_arp.o # generic IP tables diff --git a/net/ipv4/netfilter/nft_masq_ipv4.c b/net/ipv4/netfilter/nft_masq_ipv4.c new file mode 100644 index 0000000..6ea1d20 --- /dev/null +++ b/net/ipv4/netfilter/nft_masq_ipv4.c @@ -0,0 +1,89 @@ +/* + * Copyright (c) 2014 Arturo Borrero Gonzalez + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +static void nft_masq_ipv4_eval(const struct nft_expr *expr, + struct nft_data data[NFT_REG_MAX + 1], + const struct nft_pktinfo *pkt) +{ + struct nft_masq *priv = nft_expr_priv(expr); + struct nf_nat_range range; + unsigned int verdict; + + range.flags = priv->flags; + + verdict = nf_nat_masquerade_ipv4(pkt->skb, pkt->ops->hooknum, + &range, pkt->out); + + data[NFT_REG_VERDICT].verdict = verdict; +} + +static int nft_masq_ipv4_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + int err; + + err = nft_masq_init(ctx, expr, tb); + if (err < 0) + return err; + + nf_nat_masquerade_ipv4_register_notifier(); + return 0; +} + +static void nft_masq_ipv4_destroy(const struct nft_ctx *ctx, + const struct nft_expr *expr) +{ + nf_nat_masquerade_ipv4_unregister_notifier(); +} + +static struct nft_expr_type nft_masq_ipv4_type; +static const struct nft_expr_ops nft_masq_ipv4_ops = { + .type = &nft_masq_ipv4_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_masq)), + .eval = nft_masq_ipv4_eval, + .init = nft_masq_ipv4_init, + .destroy = nft_masq_ipv4_destroy, + .dump = nft_masq_dump, +}; + +static struct nft_expr_type nft_masq_ipv4_type __read_mostly = { + .family = NFPROTO_IPV4, + .name = "masq", + .ops = &nft_masq_ipv4_ops, + .policy = nft_masq_policy, + .maxattr = NFTA_MASQ_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_masq_ipv4_module_init(void) +{ + return nft_register_expr(&nft_masq_ipv4_type); +} + +static void __exit nft_masq_ipv4_module_exit(void) +{ + nft_unregister_expr(&nft_masq_ipv4_type); +} + +module_init(nft_masq_ipv4_module_init); +module_exit(nft_masq_ipv4_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Arturo Borrero Gonzalez "); +MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "masq"); diff --git a/net/ipv6/netfilter/Kconfig b/net/ipv6/netfilter/Kconfig index 6c8cfec..24c535f 100644 --- a/net/ipv6/netfilter/Kconfig +++ b/net/ipv6/netfilter/Kconfig @@ -252,6 +252,12 @@ config NF_NAT_MASQUERADE_IPV6 This is the kernel functionality to provide NAT in the masquerade flavour (automatic source address selection) for IPv6. +config NFT_MASQ_IPV6 + tristate "IPv6 masquerade support for nf_tables" + depends on NF_TABLES_IPV6 + depends on NFT_MASQ + select NF_NAT_MASQUERADE_IPV6 + config IP6_NF_TARGET_MASQUERADE tristate "MASQUERADE target support" select NF_NAT_MASQUERADE_IPV6 diff --git a/net/ipv6/netfilter/Makefile b/net/ipv6/netfilter/Makefile index 89a0bd7..482c4df 100644 --- a/net/ipv6/netfilter/Makefile +++ b/net/ipv6/netfilter/Makefile @@ -32,6 +32,7 @@ obj-$(CONFIG_NF_TABLES_IPV6) += nf_tables_ipv6.o obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV6) += nft_chain_route_ipv6.o obj-$(CONFIG_NFT_CHAIN_NAT_IPV6) += nft_chain_nat_ipv6.o obj-$(CONFIG_NFT_REJECT_IPV6) += nft_reject_ipv6.o +obj-$(CONFIG_NFT_MASQ_IPV6) += nft_masq_ipv6.o # matches obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o diff --git a/net/ipv6/netfilter/nft_masq_ipv6.c b/net/ipv6/netfilter/nft_masq_ipv6.c new file mode 100644 index 0000000..4e51334 --- /dev/null +++ b/net/ipv6/netfilter/nft_masq_ipv6.c @@ -0,0 +1,89 @@ +/* + * Copyright (c) 2014 Arturo Borrero Gonzalez + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static void nft_masq_ipv6_eval(const struct nft_expr *expr, + struct nft_data data[NFT_REG_MAX + 1], + const struct nft_pktinfo *pkt) +{ + struct nft_masq *priv = nft_expr_priv(expr); + struct nf_nat_range range; + unsigned int verdict; + + range.flags = priv->flags; + + verdict = nf_nat_masquerade_ipv6(pkt->skb, &range, pkt->out); + + data[NFT_REG_VERDICT].verdict = verdict; +} + +static int nft_masq_ipv6_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + int err; + + err = nft_masq_init(ctx, expr, tb); + if (err < 0) + return err; + + nf_nat_masquerade_ipv6_register_notifier(); + return 0; +} + +static void nft_masq_ipv6_destroy(const struct nft_ctx *ctx, + const struct nft_expr *expr) +{ + nf_nat_masquerade_ipv6_unregister_notifier(); +} + +static struct nft_expr_type nft_masq_ipv6_type; +static const struct nft_expr_ops nft_masq_ipv6_ops = { + .type = &nft_masq_ipv6_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_masq)), + .eval = nft_masq_ipv6_eval, + .init = nft_masq_ipv6_init, + .destroy = nft_masq_ipv6_destroy, + .dump = nft_masq_dump, +}; + +static struct nft_expr_type nft_masq_ipv6_type __read_mostly = { + .family = NFPROTO_IPV6, + .name = "masq", + .ops = &nft_masq_ipv6_ops, + .policy = nft_masq_policy, + .maxattr = NFTA_MASQ_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_masq_ipv6_module_init(void) +{ + return nft_register_expr(&nft_masq_ipv6_type); +} + +static void __exit nft_masq_ipv6_module_exit(void) +{ + nft_unregister_expr(&nft_masq_ipv6_type); +} + +module_init(nft_masq_ipv6_module_init); +module_exit(nft_masq_ipv6_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Arturo Borrero Gonzalez "); +MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "masq"); diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index ad751fe..3742872 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -496,6 +496,15 @@ config NFT_LIMIT This option adds the "limit" expression that you can use to ratelimit rule matchings. +config NFT_MASQ + depends on NF_TABLES + depends on NF_CONNTRACK + depends on NF_NAT + tristate "Netfilter nf_tables masquerade support" + help + This option adds the "masquerade" expression that you can use + to perform NAT in the masquerade flavour. + config NFT_NAT depends on NF_TABLES depends on NF_CONNTRACK diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 8308624..0637792 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -87,6 +87,7 @@ obj-$(CONFIG_NFT_RBTREE) += nft_rbtree.o obj-$(CONFIG_NFT_HASH) += nft_hash.o obj-$(CONFIG_NFT_COUNTER) += nft_counter.o obj-$(CONFIG_NFT_LOG) += nft_log.o +obj-$(CONFIG_NFT_MASQ) += nft_masq.o # generic X tables obj-$(CONFIG_NETFILTER_XTABLES) += x_tables.o xt_tcpudp.o diff --git a/net/netfilter/nft_masq.c b/net/netfilter/nft_masq.c new file mode 100644 index 0000000..6637bab --- /dev/null +++ b/net/netfilter/nft_masq.c @@ -0,0 +1,59 @@ +/* + * Copyright (c) 2014 Arturo Borrero Gonzalez + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +const struct nla_policy nft_masq_policy[NFTA_MASQ_MAX + 1] = { + [NFTA_MASQ_FLAGS] = { .type = NLA_U32 }, +}; +EXPORT_SYMBOL_GPL(nft_masq_policy); + +int nft_masq_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_masq *priv = nft_expr_priv(expr); + + if (tb[NFTA_MASQ_FLAGS] == NULL) + return 0; + + priv->flags = ntohl(nla_get_be32(tb[NFTA_MASQ_FLAGS])); + if (priv->flags & ~NF_NAT_RANGE_MASK) + return -EINVAL; + + return 0; +} +EXPORT_SYMBOL_GPL(nft_masq_init); + +int nft_masq_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_masq *priv = nft_expr_priv(expr); + + if (priv->flags == 0) + return 0; + + if (nla_put_be32(skb, NFTA_MASQ_FLAGS, htonl(priv->flags))) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -1; +} +EXPORT_SYMBOL_GPL(nft_masq_dump); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Arturo Borrero Gonzalez "); -- 2.7.4