From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: [PATCH nf-next 3/3] netfilter: nf_tables: add nft_dup expression Date: Tue, 4 Aug 2015 12:27:22 +0200 Message-ID: <1438684042-13709-3-git-send-email-pablo@netfilter.org> References: <1438684042-13709-1-git-send-email-pablo@netfilter.org> Cc: kaber@trash.net To: netfilter-devel@vger.kernel.org Return-path: Received: from mail.us.es ([193.147.175.20]:33627 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755405AbbHDKVf (ORCPT ); Tue, 4 Aug 2015 06:21:35 -0400 In-Reply-To: <1438684042-13709-1-git-send-email-pablo@netfilter.org> Sender: netfilter-devel-owner@vger.kernel.org List-ID: This new expression uses the nf_dup engine to clone packets to a given gateway. Unlike xt_TEE, we use an index to indicate output interface which should be fine at this stage. Moreover, change to the preemtion-safe this_cpu_read(nf_skb_duplicated) from nf_dup_ipv{4,6} to silence a lockdep splat. Based on the original tee expression from Arturo Borrero Gonzalez, although this patch has diverted quite a bit from this initial effort due to the change to support maps. Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nft_dup.h | 9 +++ include/uapi/linux/netfilter/nf_tables.h | 14 ++++ net/ipv4/netfilter/Kconfig | 6 ++ net/ipv4/netfilter/Makefile | 1 + net/ipv4/netfilter/nf_dup_ipv4.c | 2 +- net/ipv4/netfilter/nft_dup_ipv4.c | 110 ++++++++++++++++++++++++++++++ net/ipv6/netfilter/Kconfig | 6 ++ net/ipv6/netfilter/Makefile | 1 + net/ipv6/netfilter/nf_dup_ipv6.c | 2 +- net/ipv6/netfilter/nft_dup_ipv6.c | 108 +++++++++++++++++++++++++++++ 10 files changed, 257 insertions(+), 2 deletions(-) create mode 100644 include/net/netfilter/nft_dup.h create mode 100644 net/ipv4/netfilter/nft_dup_ipv4.c create mode 100644 net/ipv6/netfilter/nft_dup_ipv6.c diff --git a/include/net/netfilter/nft_dup.h b/include/net/netfilter/nft_dup.h new file mode 100644 index 0000000..6b84cf6 --- /dev/null +++ b/include/net/netfilter/nft_dup.h @@ -0,0 +1,9 @@ +#ifndef _NFT_DUP_H_ +#define _NFT_DUP_H_ + +struct nft_dup_inet { + enum nft_registers sreg_addr:8; + enum nft_registers sreg_dev:8; +}; + +#endif /* _NFT_DUP_H_ */ diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index a99e6a9..059ed29 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -936,6 +936,20 @@ enum nft_redir_attributes { #define NFTA_REDIR_MAX (__NFTA_REDIR_MAX - 1) /** + * enum nft_tee_attributes - nf_tables tee expression netlink attributes + * + * @NFTA_DUP_SREG_ADDR: source register of address (NLA_U32: nft_registers) + * @NFTA_DUP_SREG_DEV: source register of output interface (NLA_U32: nft_register) + */ +enum nft_tee_attributes { + NFTA_DUP_UNSPEC, + NFTA_DUP_SREG_ADDR, + NFTA_DUP_SREG_DEV, + __NFTA_DUP_MAX +}; +#define NFTA_DUP_MAX (__NFTA_DUP_MAX - 1) + +/** * enum nft_gen_attributes - nf_tables ruleset generation attributes * * @NFTA_GEN_ID: Ruleset generation ID (NLA_U32) diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig index 0142ea2..799fb2b 100644 --- a/net/ipv4/netfilter/Kconfig +++ b/net/ipv4/netfilter/Kconfig @@ -58,6 +58,12 @@ config NFT_REJECT_IPV4 default NFT_REJECT tristate +config NFT_DUP_IPV4 + tristate "IPv4 tee suport for nf_tables" + select NF_DUP_IPV4 + help + This is the module that provides IPv4 tee support for nf_tables. + endif # NF_TABLES_IPV4 config NF_TABLES_ARP diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile index 9136ffc..87b073d 100644 --- a/net/ipv4/netfilter/Makefile +++ b/net/ipv4/netfilter/Makefile @@ -41,6 +41,7 @@ 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_NFT_REDIR_IPV4) += nft_redir_ipv4.o +obj-$(CONFIG_NFT_DUP_IPV4) += nft_dup_ipv4.o obj-$(CONFIG_NF_TABLES_ARP) += nf_tables_arp.o # generic IP tables diff --git a/net/ipv4/netfilter/nf_dup_ipv4.c b/net/ipv4/netfilter/nf_dup_ipv4.c index feba24a..5a9cf5e 100644 --- a/net/ipv4/netfilter/nf_dup_ipv4.c +++ b/net/ipv4/netfilter/nf_dup_ipv4.c @@ -69,7 +69,7 @@ unsigned int nf_dup_ipv4(struct sk_buff *skb, unsigned int hooknum, { struct iphdr *iph; - if (__this_cpu_read(nf_skb_duplicated)) + if (this_cpu_read(nf_skb_duplicated)) return XT_CONTINUE; /* * Copy the skb, and route the copy. Will later return %XT_CONTINUE for diff --git a/net/ipv4/netfilter/nft_dup_ipv4.c b/net/ipv4/netfilter/nft_dup_ipv4.c new file mode 100644 index 0000000..25419fb --- /dev/null +++ b/net/ipv4/netfilter/nft_dup_ipv4.c @@ -0,0 +1,110 @@ +/* + * 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_dup_ipv4 { + enum nft_registers sreg_addr:8; + enum nft_registers sreg_dev:8; +}; + +static void nft_dup_ipv4_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + struct nft_dup_ipv4 *priv = nft_expr_priv(expr); + struct in_addr gw = { + .s_addr = regs->data[priv->sreg_addr], + }; + int oif = regs->data[priv->sreg_dev]; + + nf_dup_ipv4(pkt->skb, pkt->ops->hooknum, &gw, oif); +} + +static int nft_dup_ipv4_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_dup_ipv4 *priv = nft_expr_priv(expr); + int err; + + if (tb[NFTA_DUP_SREG_ADDR] == NULL) + return -EINVAL; + + priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]); + err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in_addr)); + if (err < 0) + return err; + + if (tb[NFTA_DUP_SREG_DEV] != NULL) { + priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]); + return nft_validate_register_load(priv->sreg_dev, sizeof(int)); + } + return 0; +} + +static int nft_dup_ipv4_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + struct nft_dup_ipv4 *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_DUP_SREG_ADDR, priv->sreg_addr) || + nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev)) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_dup_ipv4_type; +static const struct nft_expr_ops nft_dup_ipv4_ops = { + .type = &nft_dup_ipv4_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv4)), + .eval = nft_dup_ipv4_eval, + .init = nft_dup_ipv4_init, + .dump = nft_dup_ipv4_dump, +}; + +static const struct nla_policy nft_dup_ipv4_policy[NFTA_DUP_MAX + 1] = { + [NFTA_DUP_SREG_ADDR] = { .type = NLA_U32 }, + [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 }, +}; + +static struct nft_expr_type nft_dup_ipv4_type __read_mostly = { + .family = NFPROTO_IPV4, + .name = "dup", + .ops = &nft_dup_ipv4_ops, + .policy = nft_dup_ipv4_policy, + .maxattr = NFTA_DUP_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_dup_ipv4_module_init(void) +{ + return nft_register_expr(&nft_dup_ipv4_type); +} + +static void __exit nft_dup_ipv4_module_exit(void) +{ + nft_unregister_expr(&nft_dup_ipv4_type); +} + +module_init(nft_dup_ipv4_module_init); +module_exit(nft_dup_ipv4_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Pablo Neira Ayuso "); +MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "dup"); diff --git a/net/ipv6/netfilter/Kconfig b/net/ipv6/netfilter/Kconfig index 298daf3..496ad16 100644 --- a/net/ipv6/netfilter/Kconfig +++ b/net/ipv6/netfilter/Kconfig @@ -47,6 +47,12 @@ config NFT_REJECT_IPV6 default NFT_REJECT tristate +config NFT_DUP_IPV6 + tristate "IPv6 tee support for nf_tables" + select NF_DUP_IPV6 + help + This is the module that provides IPv6 tee support for nf_tables. + endif # NF_TABLES_IPV6 endif # NF_TABLES diff --git a/net/ipv6/netfilter/Makefile b/net/ipv6/netfilter/Makefile index dc6c732..b4f7d0b 100644 --- a/net/ipv6/netfilter/Makefile +++ b/net/ipv6/netfilter/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_NFT_CHAIN_NAT_IPV6) += nft_chain_nat_ipv6.o obj-$(CONFIG_NFT_REJECT_IPV6) += nft_reject_ipv6.o obj-$(CONFIG_NFT_MASQ_IPV6) += nft_masq_ipv6.o obj-$(CONFIG_NFT_REDIR_IPV6) += nft_redir_ipv6.o +obj-$(CONFIG_NFT_DUP_IPV6) += nft_dup_ipv6.o # matches obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o diff --git a/net/ipv6/netfilter/nf_dup_ipv6.c b/net/ipv6/netfilter/nf_dup_ipv6.c index ca7e867..a4b72ad 100644 --- a/net/ipv6/netfilter/nf_dup_ipv6.c +++ b/net/ipv6/netfilter/nf_dup_ipv6.c @@ -63,7 +63,7 @@ static bool nf_dup_ipv6_route(struct sk_buff *skb, const struct in6_addr *gw, unsigned int nf_dup_ipv6(struct sk_buff *skb, unsigned int hooknum, const struct in6_addr *gw, int oif) { - if (__this_cpu_read(nf_skb_duplicated)) + if (this_cpu_read(nf_skb_duplicated)) return XT_CONTINUE; skb = pskb_copy(skb, GFP_ATOMIC); if (skb == NULL) diff --git a/net/ipv6/netfilter/nft_dup_ipv6.c b/net/ipv6/netfilter/nft_dup_ipv6.c new file mode 100644 index 0000000..0eaa4f6 --- /dev/null +++ b/net/ipv6/netfilter/nft_dup_ipv6.c @@ -0,0 +1,108 @@ +/* + * 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_dup_ipv6 { + enum nft_registers sreg_addr:8; + enum nft_registers sreg_dev:8; +}; + +static void nft_dup_ipv6_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + struct nft_dup_ipv6 *priv = nft_expr_priv(expr); + struct in6_addr *gw = (struct in6_addr *)®s->data[priv->sreg_addr]; + int oif = regs->data[priv->sreg_dev]; + + nf_dup_ipv6(pkt->skb, pkt->ops->hooknum, gw, oif); +} + +static int nft_dup_ipv6_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_dup_ipv6 *priv = nft_expr_priv(expr); + int err; + + if (tb[NFTA_DUP_SREG_ADDR] == NULL) + return -EINVAL; + + priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]); + err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in6_addr)); + if (err < 0) + return err; + + if (tb[NFTA_DUP_SREG_DEV] != NULL) { + priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]); + return nft_validate_register_load(priv->sreg_dev, sizeof(int)); + } + return 0; +} + +static int nft_dup_ipv6_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + struct nft_dup_ipv6 *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_DUP_SREG_ADDR, priv->sreg_addr) || + nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev)) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_dup_ipv6_type; +static const struct nft_expr_ops nft_dup_ipv6_ops = { + .type = &nft_dup_ipv6_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv6)), + .eval = nft_dup_ipv6_eval, + .init = nft_dup_ipv6_init, + .dump = nft_dup_ipv6_dump, +}; + +static const struct nla_policy nft_dup_ipv6_policy[NFTA_DUP_MAX + 1] = { + [NFTA_DUP_SREG_ADDR] = { .type = NLA_U32 }, + [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 }, +}; + +static struct nft_expr_type nft_dup_ipv6_type __read_mostly = { + .family = NFPROTO_IPV6, + .name = "dup", + .ops = &nft_dup_ipv6_ops, + .policy = nft_dup_ipv6_policy, + .maxattr = NFTA_DUP_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_dup_ipv6_module_init(void) +{ + return nft_register_expr(&nft_dup_ipv6_type); +} + +static void __exit nft_dup_ipv6_module_exit(void) +{ + nft_unregister_expr(&nft_dup_ipv6_type); +} + +module_init(nft_dup_ipv6_module_init); +module_exit(nft_dup_ipv6_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Pablo Neira Ayuso "); +MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "dup"); -- 1.7.10.4