diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 22043ce95ae6..731288a039f6 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -983,6 +983,18 @@ enum nft_dup_attributes { }; #define NFTA_DUP_MAX (__NFTA_DUP_MAX - 1) +/** + * enum nft_fwd_attributes - nf_tables fwd expression netlink attributes + * + * @NFTA_FWD_SREG_DEV: source register of output interface (NLA_U32: nft_register) + */ +enum nft_fwd_attributes { + NFTA_FWD_UNSPEC, + NFTA_FWD_SREG_DEV, + __NFTA_FWD_MAX +}; +#define NFTA_FWD_MAX (__NFTA_FWD_MAX - 1) + /** * enum nft_gen_attributes - nf_tables ruleset generation attributes * diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index 8514cc4b22a8..8c067e6663a1 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -577,6 +577,12 @@ config NFT_DUP_NETDEV help This option enables packet duplication for the "netdev" family. +config NFT_FWD_NETDEV + tristate "Netfilter nf_tables netdev packet forwarding support" + select NF_DUP_NETDEV + help + This option enables packet forwarding for the "netdev" family. + endif # NF_TABLES_NETDEV endif # NF_TABLES diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 5c9913359537..69134541d65b 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -95,6 +95,7 @@ obj-$(CONFIG_NFT_REDIR) += nft_redir.o # nf_tables netdev obj-$(CONFIG_NFT_DUP_NETDEV) += nft_dup_netdev.o +obj-$(CONFIG_NFT_FWD_NETDEV) += nft_fwd_netdev.o # generic X tables obj-$(CONFIG_NETFILTER_XTABLES) += x_tables.o xt_tcpudp.o diff --git a/net/netfilter/nft_fwd_netdev.c b/net/netfilter/nft_fwd_netdev.c new file mode 100644 index 000000000000..763ebc3e0b2b --- /dev/null +++ b/net/netfilter/nft_fwd_netdev.c @@ -0,0 +1,98 @@ +/* + * Copyright (c) 2015 Pablo Neira Ayuso + * + * 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 + +struct nft_fwd_netdev { + enum nft_registers sreg_dev:8; +}; + +static void nft_fwd_netdev_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + struct nft_fwd_netdev *priv = nft_expr_priv(expr); + int oif = regs->data[priv->sreg_dev]; + + nf_dup_netdev_egress(pkt, oif); + regs->verdict.code = NF_DROP; +} + +static const struct nla_policy nft_fwd_netdev_policy[NFTA_FWD_MAX + 1] = { + [NFTA_FWD_SREG_DEV] = { .type = NLA_U32 }, +}; + +static int nft_fwd_netdev_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_fwd_netdev *priv = nft_expr_priv(expr); + + if (tb[NFTA_FWD_SREG_DEV] == NULL) + return -EINVAL; + + priv->sreg_dev = nft_parse_register(tb[NFTA_FWD_SREG_DEV]); + return nft_validate_register_load(priv->sreg_dev, sizeof(int)); +} + +static const struct nft_expr_ops nft_fwd_netdev_ingress_ops; + +static int nft_fwd_netdev_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + struct nft_fwd_netdev *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_FWD_SREG_DEV, priv->sreg_dev)) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_fwd_netdev_type; +static const struct nft_expr_ops nft_fwd_netdev_ops = { + .type = &nft_fwd_netdev_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_fwd_netdev)), + .eval = nft_fwd_netdev_eval, + .init = nft_fwd_netdev_init, + .dump = nft_fwd_netdev_dump, +}; + +static struct nft_expr_type nft_fwd_netdev_type __read_mostly = { + .family = NFPROTO_NETDEV, + .name = "fwd", + .ops = &nft_fwd_netdev_ops, + .policy = nft_fwd_netdev_policy, + .maxattr = NFTA_FWD_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_fwd_netdev_module_init(void) +{ + return nft_register_expr(&nft_fwd_netdev_type); +} + +static void __exit nft_fwd_netdev_module_exit(void) +{ + nft_unregister_expr(&nft_fwd_netdev_type); +} + +module_init(nft_fwd_netdev_module_init); +module_exit(nft_fwd_netdev_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Pablo Neira Ayuso "); +MODULE_ALIAS_NFT_AF_EXPR(5, "fwd");