From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14D45C83004 for ; Wed, 29 Apr 2020 19:48:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EF0B921D79 for ; Wed, 29 Apr 2020 19:48:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727918AbgD2Ts0 (ORCPT ); Wed, 29 Apr 2020 15:48:26 -0400 Received: from correo.us.es ([193.147.175.20]:50014 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726775AbgD2TsJ (ORCPT ); Wed, 29 Apr 2020 15:48:09 -0400 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 65C68E1717 for ; Wed, 29 Apr 2020 21:42:53 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 5A738BAAB5 for ; Wed, 29 Apr 2020 21:42:53 +0200 (CEST) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 50094BAAB1; Wed, 29 Apr 2020 21:42:53 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 5A6FDDA736; Wed, 29 Apr 2020 21:42:51 +0200 (CEST) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Wed, 29 Apr 2020 21:42:51 +0200 (CEST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from localhost.localdomain (unknown [90.77.255.23]) (Authenticated sender: pneira@us.es) by entrada.int (Postfix) with ESMTPA id 36B2B42EF9E0; Wed, 29 Apr 2020 21:42:51 +0200 (CEST) X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org Subject: [PATCH 6/6] netfilter: nft_nat: add netmap support Date: Wed, 29 Apr 2020 21:42:43 +0200 Message-Id: <20200429194243.22228-7-pablo@netfilter.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200429194243.22228-1-pablo@netfilter.org> References: <20200429194243.22228-1-pablo@netfilter.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Virus-Scanned: ClamAV using ClamSMTP Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org This patch allows you to NAT the network address prefix onto another network address prefix, a.k.a. netmapping. Userspace must specify the NF_NAT_RANGE_NETMAP flag and the prefix address through the NFTA_NAT_REG_ADDR_MIN and NFTA_NAT_REG_ADDR_MAX netlink attributes. Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_nat.h | 4 ++- net/netfilter/nft_nat.c | 46 ++++++++++++++++++++++++++- 2 files changed, 48 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/netfilter/nf_nat.h b/include/uapi/linux/netfilter/nf_nat.h index 4a95c0db14d4..a64586e77b24 100644 --- a/include/uapi/linux/netfilter/nf_nat.h +++ b/include/uapi/linux/netfilter/nf_nat.h @@ -11,6 +11,7 @@ #define NF_NAT_RANGE_PERSISTENT (1 << 3) #define NF_NAT_RANGE_PROTO_RANDOM_FULLY (1 << 4) #define NF_NAT_RANGE_PROTO_OFFSET (1 << 5) +#define NF_NAT_RANGE_NETMAP (1 << 6) #define NF_NAT_RANGE_PROTO_RANDOM_ALL \ (NF_NAT_RANGE_PROTO_RANDOM | NF_NAT_RANGE_PROTO_RANDOM_FULLY) @@ -18,7 +19,8 @@ #define NF_NAT_RANGE_MASK \ (NF_NAT_RANGE_MAP_IPS | NF_NAT_RANGE_PROTO_SPECIFIED | \ NF_NAT_RANGE_PROTO_RANDOM | NF_NAT_RANGE_PERSISTENT | \ - NF_NAT_RANGE_PROTO_RANDOM_FULLY | NF_NAT_RANGE_PROTO_OFFSET) + NF_NAT_RANGE_PROTO_RANDOM_FULLY | NF_NAT_RANGE_PROTO_OFFSET | \ + NF_NAT_RANGE_NETMAP) struct nf_nat_ipv4_range { unsigned int flags; diff --git a/net/netfilter/nft_nat.c b/net/netfilter/nft_nat.c index 7442aa8b1555..23a7bfd10521 100644 --- a/net/netfilter/nft_nat.c +++ b/net/netfilter/nft_nat.c @@ -60,6 +60,46 @@ static void nft_nat_setup_proto(struct nf_nat_range2 *range, nft_reg_load16(®s->data[priv->sreg_proto_max]); } +static void nft_nat_setup_netmap(struct nf_nat_range2 *range, + const struct nft_pktinfo *pkt, + const struct nft_nat *priv) +{ + struct sk_buff *skb = pkt->skb; + union nf_inet_addr new_addr; + __be32 netmask; + int i, len = 0; + + switch (priv->type) { + case NFT_NAT_SNAT: + if (nft_pf(pkt) == NFPROTO_IPV4) { + new_addr.ip = ip_hdr(skb)->saddr; + len = sizeof(struct in_addr); + } else { + new_addr.in6 = ipv6_hdr(skb)->saddr; + len = sizeof(struct in6_addr); + } + break; + case NFT_NAT_DNAT: + if (nft_pf(pkt) == NFPROTO_IPV4) { + new_addr.ip = ip_hdr(skb)->daddr; + len = sizeof(struct in_addr); + } else { + new_addr.in6 = ipv6_hdr(skb)->daddr; + len = sizeof(struct in6_addr); + } + break; + } + + for (i = 0; i < len / sizeof(__be32); i++) { + netmask = ~(range->min_addr.ip6[i] ^ range->max_addr.ip6[i]); + new_addr.ip6[i] &= ~netmask; + new_addr.ip6[i] |= range->min_addr.ip6[i] & netmask; + } + + range->min_addr = new_addr; + range->max_addr = new_addr; +} + static void nft_nat_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) @@ -70,8 +110,12 @@ static void nft_nat_eval(const struct nft_expr *expr, struct nf_nat_range2 range; memset(&range, 0, sizeof(range)); - if (priv->sreg_addr_min) + + if (priv->sreg_addr_min) { nft_nat_setup_addr(&range, regs, priv); + if (priv->flags & NF_NAT_RANGE_NETMAP) + nft_nat_setup_netmap(&range, pkt, priv); + } if (priv->sreg_proto_min) nft_nat_setup_proto(&range, regs, priv); -- 2.20.1