From patchwork Sat Mar 2 18:34:34 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 1050672 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=netfilter.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44BZjD2S1Dz9sBr for ; Sun, 3 Mar 2019 05:35:28 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727248AbfCBSf0 (ORCPT ); Sat, 2 Mar 2019 13:35:26 -0500 Received: from mail.us.es ([193.147.175.20]:35768 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727106AbfCBSfU (ORCPT ); Sat, 2 Mar 2019 13:35:20 -0500 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 6B7221361B5 for ; Sat, 2 Mar 2019 19:35:14 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 3C477DA878 for ; Sat, 2 Mar 2019 19:35:14 +0100 (CET) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 31968DA84C; Sat, 2 Mar 2019 19:35:14 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on antivirus1-rhel7.int X-Spam-Level: X-Spam-Status: No, score=-108.2 required=7.5 tests=ALL_TRUSTED,BAYES_50, SMTPAUTH_US2,USER_IN_WHITELIST autolearn=disabled version=3.4.1 Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 74DA1DA86A; Sat, 2 Mar 2019 19:35:10 +0100 (CET) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Sat, 02 Mar 2019 19:35:10 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from salvia.here (unknown [31.4.223.53]) (Authenticated sender: pneira@us.es) by entrada.int (Postfix) with ESMTPA id D790C4265A2F; Sat, 2 Mar 2019 19:35:09 +0100 (CET) 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 06/29] netfilter: nat: merge nf_nat_ipv4,6 into nat core Date: Sat, 2 Mar 2019 19:34:34 +0100 Message-Id: <20190302183457.3079-7-pablo@netfilter.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190302183457.3079-1-pablo@netfilter.org> References: <20190302183457.3079-1-pablo@netfilter.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Florian Westphal before: text data bss dec hex filename 16566 1576 4136 22278 5706 nf_nat.ko 3598 844 0 4442 115a nf_nat_ipv6.ko 3187 844 0 4031 fbf nf_nat_ipv4.ko after: text data bss dec hex filename 22948 1612 4136 28696 7018 nf_nat.ko ... with ipv4/v6 nat now provided directly via nf_nat.ko. Also changes: ret = nf_nat_ipv4_fn(priv, skb, state); if (ret != NF_DROP && ret != NF_STOLEN && into if (ret != NF_ACCEPT) return ret; everywhere. The nat hooks never should return anything other than ACCEPT or DROP (and the latter only in rare error cases). The original code uses multi-line ANDing including assignment-in-if: if (ret != NF_DROP && ret != NF_STOLEN && !(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) && (ct = nf_ct_get(skb, &ctinfo)) != NULL) { I removed this while moving, breaking those in separate conditionals and moving the assignments into extra lines. checkpatch still generates some warnings: 1. Overly long lines (of moved code). Breaking them is even more ugly. so I kept this as-is. 2. use of extern function declarations in a .c file. This is necessary evil, we must call nf_nat_l3proto_register() from the nat core now. All l3proto related functions are removed later in this series, those prototypes are then removed as well. v2: keep empty nf_nat_ipv6_csum_update stub for CONFIG_IPV6=n case. v3: remove IS_ENABLED(NF_NAT_IPV4/6) tests, NF_NAT_IPVx toggles are removed here. v4: also get rid of the assignments in conditionals. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/ipv4/netfilter/Kconfig | 15 +- net/ipv4/netfilter/Makefile | 3 - net/ipv4/netfilter/nf_nat_l3proto_ipv4.c | 330 --------------- net/ipv6/netfilter/Kconfig | 15 +- net/ipv6/netfilter/Makefile | 3 - net/ipv6/netfilter/nf_nat_l3proto_ipv6.c | 367 ----------------- net/netfilter/Kconfig | 8 +- net/netfilter/nf_nat_core.c | 17 + net/netfilter/nf_nat_proto.c | 678 +++++++++++++++++++++++++++++++ net/openvswitch/Kconfig | 2 - net/openvswitch/conntrack.c | 8 +- tools/testing/selftests/net/config | 3 +- 12 files changed, 711 insertions(+), 738 deletions(-) delete mode 100644 net/ipv4/netfilter/nf_nat_l3proto_ipv4.c delete mode 100644 net/ipv6/netfilter/nf_nat_l3proto_ipv6.c diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig index db05a835748a..8688461ed077 100644 --- a/net/ipv4/netfilter/Kconfig +++ b/net/ipv4/netfilter/Kconfig @@ -94,17 +94,7 @@ config NF_REJECT_IPV4 tristate "IPv4 packet rejection" default m if NETFILTER_ADVANCED=n -config NF_NAT_IPV4 - tristate "IPv4 NAT" - depends on NF_CONNTRACK - default m if NETFILTER_ADVANCED=n - select NF_NAT - help - The IPv4 NAT option allows masquerading, port forwarding and other - forms of full Network Address Port Translation. This can be - controlled by iptables or nft. - -if NF_NAT_IPV4 +if NF_NAT if NF_TABLES config NFT_CHAIN_NAT_IPV4 @@ -163,7 +153,7 @@ config NF_NAT_H323 depends on NF_CONNTRACK default NF_CONNTRACK_H323 -endif # NF_NAT_IPV4 +endif # NF_NAT config IP_NF_IPTABLES tristate "IP tables support (required for filtering/masq/NAT)" @@ -260,7 +250,6 @@ config IP_NF_NAT depends on NF_CONNTRACK default m if NETFILTER_ADVANCED=n select NF_NAT - select NF_NAT_IPV4 select NETFILTER_XT_NAT help This enables the `nat' table in iptables. This allows masquerading, diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile index ddeb35ab8bdb..b2cdf705fdf1 100644 --- a/net/ipv4/netfilter/Makefile +++ b/net/ipv4/netfilter/Makefile @@ -3,9 +3,6 @@ # Makefile for the netfilter modules on top of IPv4. # -nf_nat_ipv4-y := nf_nat_l3proto_ipv4.o -obj-$(CONFIG_NF_NAT_IPV4) += nf_nat_ipv4.o - # defrag obj-$(CONFIG_NF_DEFRAG_IPV4) += nf_defrag_ipv4.o diff --git a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c deleted file mode 100644 index 36b4f9659ffa..000000000000 --- a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c +++ /dev/null @@ -1,330 +0,0 @@ -/* - * (C) 1999-2001 Paul `Rusty' Russell - * (C) 2002-2006 Netfilter Core Team - * (C) 2011 Patrick McHardy - * - * 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 -#include - -#include -#include -#include -#include -#include - -static const struct nf_nat_l3proto nf_nat_l3proto_ipv4; - -static bool nf_nat_ipv4_manip_pkt(struct sk_buff *skb, - unsigned int iphdroff, - const struct nf_conntrack_tuple *target, - enum nf_nat_manip_type maniptype) -{ - struct iphdr *iph; - unsigned int hdroff; - - if (!skb_make_writable(skb, iphdroff + sizeof(*iph))) - return false; - - iph = (void *)skb->data + iphdroff; - hdroff = iphdroff + iph->ihl * 4; - - if (!nf_nat_l4proto_manip_pkt(skb, &nf_nat_l3proto_ipv4, iphdroff, - hdroff, target, maniptype)) - return false; - iph = (void *)skb->data + iphdroff; - - if (maniptype == NF_NAT_MANIP_SRC) { - csum_replace4(&iph->check, iph->saddr, target->src.u3.ip); - iph->saddr = target->src.u3.ip; - } else { - csum_replace4(&iph->check, iph->daddr, target->dst.u3.ip); - iph->daddr = target->dst.u3.ip; - } - return true; -} - -static void nf_nat_ipv4_csum_update(struct sk_buff *skb, - unsigned int iphdroff, __sum16 *check, - const struct nf_conntrack_tuple *t, - enum nf_nat_manip_type maniptype) -{ - struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff); - __be32 oldip, newip; - - if (maniptype == NF_NAT_MANIP_SRC) { - oldip = iph->saddr; - newip = t->src.u3.ip; - } else { - oldip = iph->daddr; - newip = t->dst.u3.ip; - } - inet_proto_csum_replace4(check, skb, oldip, newip, true); -} - -static void nf_nat_ipv4_csum_recalc(struct sk_buff *skb, - u8 proto, void *data, __sum16 *check, - int datalen, int oldlen) -{ - if (skb->ip_summed != CHECKSUM_PARTIAL) { - const struct iphdr *iph = ip_hdr(skb); - - skb->ip_summed = CHECKSUM_PARTIAL; - skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) + - ip_hdrlen(skb); - skb->csum_offset = (void *)check - data; - *check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, datalen, - proto, 0); - } else - inet_proto_csum_replace2(check, skb, - htons(oldlen), htons(datalen), true); -} - -static const struct nf_nat_l3proto nf_nat_l3proto_ipv4 = { - .l3proto = NFPROTO_IPV4, - .manip_pkt = nf_nat_ipv4_manip_pkt, - .csum_update = nf_nat_ipv4_csum_update, - .csum_recalc = nf_nat_ipv4_csum_recalc, -}; - -int nf_nat_icmp_reply_translation(struct sk_buff *skb, - struct nf_conn *ct, - enum ip_conntrack_info ctinfo, - unsigned int hooknum) -{ - struct { - struct icmphdr icmp; - struct iphdr ip; - } *inside; - enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); - enum nf_nat_manip_type manip = HOOK2MANIP(hooknum); - unsigned int hdrlen = ip_hdrlen(skb); - struct nf_conntrack_tuple target; - unsigned long statusbit; - - WARN_ON(ctinfo != IP_CT_RELATED && ctinfo != IP_CT_RELATED_REPLY); - - if (!skb_make_writable(skb, hdrlen + sizeof(*inside))) - return 0; - if (nf_ip_checksum(skb, hooknum, hdrlen, 0)) - return 0; - - inside = (void *)skb->data + hdrlen; - if (inside->icmp.type == ICMP_REDIRECT) { - if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK) - return 0; - if (ct->status & IPS_NAT_MASK) - return 0; - } - - if (manip == NF_NAT_MANIP_SRC) - statusbit = IPS_SRC_NAT; - else - statusbit = IPS_DST_NAT; - - /* Invert if this is reply direction */ - if (dir == IP_CT_DIR_REPLY) - statusbit ^= IPS_NAT_MASK; - - if (!(ct->status & statusbit)) - return 1; - - if (!nf_nat_ipv4_manip_pkt(skb, hdrlen + sizeof(inside->icmp), - &ct->tuplehash[!dir].tuple, !manip)) - return 0; - - if (skb->ip_summed != CHECKSUM_PARTIAL) { - /* Reloading "inside" here since manip_pkt may reallocate */ - inside = (void *)skb->data + hdrlen; - inside->icmp.checksum = 0; - inside->icmp.checksum = - csum_fold(skb_checksum(skb, hdrlen, - skb->len - hdrlen, 0)); - } - - /* Change outer to look like the reply to an incoming packet */ - nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); - target.dst.protonum = IPPROTO_ICMP; - if (!nf_nat_ipv4_manip_pkt(skb, 0, &target, manip)) - return 0; - - return 1; -} -EXPORT_SYMBOL_GPL(nf_nat_icmp_reply_translation); - -static unsigned int -nf_nat_ipv4_fn(void *priv, struct sk_buff *skb, - const struct nf_hook_state *state) -{ - struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - - ct = nf_ct_get(skb, &ctinfo); - if (!ct) - return NF_ACCEPT; - - if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_REPLY) { - if (ip_hdr(skb)->protocol == IPPROTO_ICMP) { - if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, - state->hook)) - return NF_DROP; - else - return NF_ACCEPT; - } - } - - return nf_nat_inet_fn(priv, skb, state); -} - -static unsigned int -nf_nat_ipv4_in(void *priv, struct sk_buff *skb, - const struct nf_hook_state *state) -{ - unsigned int ret; - __be32 daddr = ip_hdr(skb)->daddr; - - ret = nf_nat_ipv4_fn(priv, skb, state); - if (ret != NF_DROP && ret != NF_STOLEN && - daddr != ip_hdr(skb)->daddr) - skb_dst_drop(skb); - - return ret; -} - -static unsigned int -nf_nat_ipv4_out(void *priv, struct sk_buff *skb, - const struct nf_hook_state *state) -{ -#ifdef CONFIG_XFRM - const struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - int err; -#endif - unsigned int ret; - - ret = nf_nat_ipv4_fn(priv, skb, state); -#ifdef CONFIG_XFRM - if (ret != NF_DROP && ret != NF_STOLEN && - !(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) && - (ct = nf_ct_get(skb, &ctinfo)) != NULL) { - enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); - - if ((ct->tuplehash[dir].tuple.src.u3.ip != - ct->tuplehash[!dir].tuple.dst.u3.ip) || - (ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP && - ct->tuplehash[dir].tuple.src.u.all != - ct->tuplehash[!dir].tuple.dst.u.all)) { - err = nf_xfrm_me_harder(state->net, skb, AF_INET); - if (err < 0) - ret = NF_DROP_ERR(err); - } - } -#endif - return ret; -} - -static unsigned int -nf_nat_ipv4_local_fn(void *priv, struct sk_buff *skb, - const struct nf_hook_state *state) -{ - const struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - unsigned int ret; - int err; - - ret = nf_nat_ipv4_fn(priv, skb, state); - if (ret != NF_DROP && ret != NF_STOLEN && - (ct = nf_ct_get(skb, &ctinfo)) != NULL) { - enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); - - if (ct->tuplehash[dir].tuple.dst.u3.ip != - ct->tuplehash[!dir].tuple.src.u3.ip) { - err = ip_route_me_harder(state->net, skb, RTN_UNSPEC); - if (err < 0) - ret = NF_DROP_ERR(err); - } -#ifdef CONFIG_XFRM - else if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) && - ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP && - ct->tuplehash[dir].tuple.dst.u.all != - ct->tuplehash[!dir].tuple.src.u.all) { - err = nf_xfrm_me_harder(state->net, skb, AF_INET); - if (err < 0) - ret = NF_DROP_ERR(err); - } -#endif - } - return ret; -} - -static const struct nf_hook_ops nf_nat_ipv4_ops[] = { - /* Before packet filtering, change destination */ - { - .hook = nf_nat_ipv4_in, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_PRE_ROUTING, - .priority = NF_IP_PRI_NAT_DST, - }, - /* After packet filtering, change source */ - { - .hook = nf_nat_ipv4_out, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_POST_ROUTING, - .priority = NF_IP_PRI_NAT_SRC, - }, - /* Before packet filtering, change destination */ - { - .hook = nf_nat_ipv4_local_fn, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_LOCAL_OUT, - .priority = NF_IP_PRI_NAT_DST, - }, - /* After packet filtering, change source */ - { - .hook = nf_nat_ipv4_fn, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_LOCAL_IN, - .priority = NF_IP_PRI_NAT_SRC, - }, -}; - -int nf_nat_l3proto_ipv4_register_fn(struct net *net, const struct nf_hook_ops *ops) -{ - return nf_nat_register_fn(net, ops, nf_nat_ipv4_ops, ARRAY_SIZE(nf_nat_ipv4_ops)); -} -EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_register_fn); - -void nf_nat_l3proto_ipv4_unregister_fn(struct net *net, const struct nf_hook_ops *ops) -{ - nf_nat_unregister_fn(net, ops, ARRAY_SIZE(nf_nat_ipv4_ops)); -} -EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_unregister_fn); - -static int __init nf_nat_l3proto_ipv4_init(void) -{ - return nf_nat_l3proto_register(&nf_nat_l3proto_ipv4); -} - -static void __exit nf_nat_l3proto_ipv4_exit(void) -{ - nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv4); -} - -MODULE_LICENSE("GPL"); -MODULE_ALIAS("nf-nat-" __stringify(AF_INET)); - -module_init(nf_nat_l3proto_ipv4_init); -module_exit(nf_nat_l3proto_ipv4_exit); diff --git a/net/ipv6/netfilter/Kconfig b/net/ipv6/netfilter/Kconfig index f57fc99e9a04..a04a38166d8c 100644 --- a/net/ipv6/netfilter/Kconfig +++ b/net/ipv6/netfilter/Kconfig @@ -31,7 +31,7 @@ config NFT_CHAIN_ROUTE_IPV6 fields such as the source, destination, flowlabel, hop-limit and the packet mark. -if NF_NAT_IPV6 +if NF_NAT config NFT_CHAIN_NAT_IPV6 tristate "IPv6 nf_tables nat chain support" @@ -57,7 +57,7 @@ config NFT_REDIR_IPV6 This is the expression that provides IPv4 redirect support for nf_tables. -endif # NF_NAT_IPV6 +endif # NF_NAT config NFT_REJECT_IPV6 select NF_REJECT_IPV6 @@ -106,16 +106,6 @@ config NF_LOG_IPV6 default m if NETFILTER_ADVANCED=n select NF_LOG_COMMON -config NF_NAT_IPV6 - tristate "IPv6 NAT" - depends on NF_CONNTRACK - depends on NETFILTER_ADVANCED - select NF_NAT - help - The IPv6 NAT option allows masquerading, port forwarding and other - forms of full Network Address Port Translation. This can be - controlled by iptables or nft. - config IP6_NF_IPTABLES tristate "IP6 tables support (required for filtering)" depends on INET && IPV6 @@ -304,7 +294,6 @@ config IP6_NF_NAT depends on NF_CONNTRACK depends on NETFILTER_ADVANCED select NF_NAT - select NF_NAT_IPV6 select NETFILTER_XT_NAT help This enables the `nat' table in ip6tables. This allows masquerading, diff --git a/net/ipv6/netfilter/Makefile b/net/ipv6/netfilter/Makefile index a7b18d13e056..afb880427133 100644 --- a/net/ipv6/netfilter/Makefile +++ b/net/ipv6/netfilter/Makefile @@ -11,9 +11,6 @@ obj-$(CONFIG_IP6_NF_RAW) += ip6table_raw.o obj-$(CONFIG_IP6_NF_SECURITY) += ip6table_security.o obj-$(CONFIG_IP6_NF_NAT) += ip6table_nat.o -nf_nat_ipv6-y := nf_nat_l3proto_ipv6.o -obj-$(CONFIG_NF_NAT_IPV6) += nf_nat_ipv6.o - # defrag nf_defrag_ipv6-y := nf_defrag_ipv6_hooks.o nf_conntrack_reasm.o obj-$(CONFIG_NF_DEFRAG_IPV6) += nf_defrag_ipv6.o diff --git a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c deleted file mode 100644 index 5d667cf9bab8..000000000000 --- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c +++ /dev/null @@ -1,367 +0,0 @@ -/* - * Copyright (c) 2011 Patrick McHardy - * - * 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. - * - * Development of IPv6 NAT funded by Astaro. - */ -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include -#include -#include -#include -#include - -static const struct nf_nat_l3proto nf_nat_l3proto_ipv6; - -static bool nf_nat_ipv6_manip_pkt(struct sk_buff *skb, - unsigned int iphdroff, - const struct nf_conntrack_tuple *target, - enum nf_nat_manip_type maniptype) -{ - struct ipv6hdr *ipv6h; - __be16 frag_off; - int hdroff; - u8 nexthdr; - - if (!skb_make_writable(skb, iphdroff + sizeof(*ipv6h))) - return false; - - ipv6h = (void *)skb->data + iphdroff; - nexthdr = ipv6h->nexthdr; - hdroff = ipv6_skip_exthdr(skb, iphdroff + sizeof(*ipv6h), - &nexthdr, &frag_off); - if (hdroff < 0) - goto manip_addr; - - if ((frag_off & htons(~0x7)) == 0 && - !nf_nat_l4proto_manip_pkt(skb, &nf_nat_l3proto_ipv6, iphdroff, hdroff, - target, maniptype)) - return false; - - /* must reload, offset might have changed */ - ipv6h = (void *)skb->data + iphdroff; - -manip_addr: - if (maniptype == NF_NAT_MANIP_SRC) - ipv6h->saddr = target->src.u3.in6; - else - ipv6h->daddr = target->dst.u3.in6; - - return true; -} - -static void nf_nat_ipv6_csum_update(struct sk_buff *skb, - unsigned int iphdroff, __sum16 *check, - const struct nf_conntrack_tuple *t, - enum nf_nat_manip_type maniptype) -{ - const struct ipv6hdr *ipv6h = (struct ipv6hdr *)(skb->data + iphdroff); - const struct in6_addr *oldip, *newip; - - if (maniptype == NF_NAT_MANIP_SRC) { - oldip = &ipv6h->saddr; - newip = &t->src.u3.in6; - } else { - oldip = &ipv6h->daddr; - newip = &t->dst.u3.in6; - } - inet_proto_csum_replace16(check, skb, oldip->s6_addr32, - newip->s6_addr32, true); -} - -static void nf_nat_ipv6_csum_recalc(struct sk_buff *skb, - u8 proto, void *data, __sum16 *check, - int datalen, int oldlen) -{ - if (skb->ip_summed != CHECKSUM_PARTIAL) { - const struct ipv6hdr *ipv6h = ipv6_hdr(skb); - - skb->ip_summed = CHECKSUM_PARTIAL; - skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) + - (data - (void *)skb->data); - skb->csum_offset = (void *)check - data; - *check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, - datalen, proto, 0); - } else - inet_proto_csum_replace2(check, skb, - htons(oldlen), htons(datalen), true); -} - -static const struct nf_nat_l3proto nf_nat_l3proto_ipv6 = { - .l3proto = NFPROTO_IPV6, - .manip_pkt = nf_nat_ipv6_manip_pkt, - .csum_update = nf_nat_ipv6_csum_update, - .csum_recalc = nf_nat_ipv6_csum_recalc, -}; - -int nf_nat_icmpv6_reply_translation(struct sk_buff *skb, - struct nf_conn *ct, - enum ip_conntrack_info ctinfo, - unsigned int hooknum, - unsigned int hdrlen) -{ - struct { - struct icmp6hdr icmp6; - struct ipv6hdr ip6; - } *inside; - enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); - enum nf_nat_manip_type manip = HOOK2MANIP(hooknum); - struct nf_conntrack_tuple target; - unsigned long statusbit; - - WARN_ON(ctinfo != IP_CT_RELATED && ctinfo != IP_CT_RELATED_REPLY); - - if (!skb_make_writable(skb, hdrlen + sizeof(*inside))) - return 0; - if (nf_ip6_checksum(skb, hooknum, hdrlen, IPPROTO_ICMPV6)) - return 0; - - inside = (void *)skb->data + hdrlen; - if (inside->icmp6.icmp6_type == NDISC_REDIRECT) { - if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK) - return 0; - if (ct->status & IPS_NAT_MASK) - return 0; - } - - if (manip == NF_NAT_MANIP_SRC) - statusbit = IPS_SRC_NAT; - else - statusbit = IPS_DST_NAT; - - /* Invert if this is reply direction */ - if (dir == IP_CT_DIR_REPLY) - statusbit ^= IPS_NAT_MASK; - - if (!(ct->status & statusbit)) - return 1; - - if (!nf_nat_ipv6_manip_pkt(skb, hdrlen + sizeof(inside->icmp6), - &ct->tuplehash[!dir].tuple, !manip)) - return 0; - - if (skb->ip_summed != CHECKSUM_PARTIAL) { - struct ipv6hdr *ipv6h = ipv6_hdr(skb); - inside = (void *)skb->data + hdrlen; - inside->icmp6.icmp6_cksum = 0; - inside->icmp6.icmp6_cksum = - csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, - skb->len - hdrlen, IPPROTO_ICMPV6, - skb_checksum(skb, hdrlen, - skb->len - hdrlen, 0)); - } - - nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); - target.dst.protonum = IPPROTO_ICMPV6; - if (!nf_nat_ipv6_manip_pkt(skb, 0, &target, manip)) - return 0; - - return 1; -} -EXPORT_SYMBOL_GPL(nf_nat_icmpv6_reply_translation); - -static unsigned int -nf_nat_ipv6_fn(void *priv, struct sk_buff *skb, - const struct nf_hook_state *state) -{ - struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - __be16 frag_off; - int hdrlen; - u8 nexthdr; - - ct = nf_ct_get(skb, &ctinfo); - /* Can't track? It's not due to stress, or conntrack would - * have dropped it. Hence it's the user's responsibilty to - * packet filter it out, or implement conntrack/NAT for that - * protocol. 8) --RR - */ - if (!ct) - return NF_ACCEPT; - - if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_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, - state->hook, - hdrlen)) - return NF_DROP; - else - return NF_ACCEPT; - } - } - - return nf_nat_inet_fn(priv, skb, state); -} - -static unsigned int -nf_nat_ipv6_in(void *priv, struct sk_buff *skb, - const struct nf_hook_state *state) -{ - unsigned int ret; - struct in6_addr daddr = ipv6_hdr(skb)->daddr; - - ret = nf_nat_ipv6_fn(priv, skb, state); - 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_out(void *priv, struct sk_buff *skb, - const struct nf_hook_state *state) -{ -#ifdef CONFIG_XFRM - const struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - int err; -#endif - unsigned int ret; - - ret = nf_nat_ipv6_fn(priv, skb, state); -#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.dst.protonum != IPPROTO_ICMPV6 && - ct->tuplehash[dir].tuple.src.u.all != - ct->tuplehash[!dir].tuple.dst.u.all)) { - err = nf_xfrm_me_harder(state->net, skb, AF_INET6); - if (err < 0) - ret = NF_DROP_ERR(err); - } - } -#endif - return ret; -} - -static int nat_route_me_harder(struct net *net, struct sk_buff *skb) -{ -#ifdef CONFIG_IPV6_MODULE - const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops(); - - if (!v6_ops) - return -EHOSTUNREACH; - - return v6_ops->route_me_harder(net, skb); -#else - return ip6_route_me_harder(net, skb); -#endif -} - -static unsigned int -nf_nat_ipv6_local_fn(void *priv, struct sk_buff *skb, - const struct nf_hook_state *state) -{ - const struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - unsigned int ret; - int err; - - ret = nf_nat_ipv6_fn(priv, skb, state); - 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)) { - err = nat_route_me_harder(state->net, skb); - if (err < 0) - ret = NF_DROP_ERR(err); - } -#ifdef CONFIG_XFRM - else if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && - ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMPV6 && - ct->tuplehash[dir].tuple.dst.u.all != - ct->tuplehash[!dir].tuple.src.u.all) { - err = nf_xfrm_me_harder(state->net, skb, AF_INET6); - if (err < 0) - ret = NF_DROP_ERR(err); - } -#endif - } - return ret; -} - -static const struct nf_hook_ops nf_nat_ipv6_ops[] = { - /* Before packet filtering, change destination */ - { - .hook = nf_nat_ipv6_in, - .pf = NFPROTO_IPV6, - .hooknum = NF_INET_PRE_ROUTING, - .priority = NF_IP6_PRI_NAT_DST, - }, - /* After packet filtering, change source */ - { - .hook = nf_nat_ipv6_out, - .pf = NFPROTO_IPV6, - .hooknum = NF_INET_POST_ROUTING, - .priority = NF_IP6_PRI_NAT_SRC, - }, - /* Before packet filtering, change destination */ - { - .hook = nf_nat_ipv6_local_fn, - .pf = NFPROTO_IPV6, - .hooknum = NF_INET_LOCAL_OUT, - .priority = NF_IP6_PRI_NAT_DST, - }, - /* After packet filtering, change source */ - { - .hook = nf_nat_ipv6_fn, - .pf = NFPROTO_IPV6, - .hooknum = NF_INET_LOCAL_IN, - .priority = NF_IP6_PRI_NAT_SRC, - }, -}; - -int nf_nat_l3proto_ipv6_register_fn(struct net *net, const struct nf_hook_ops *ops) -{ - return nf_nat_register_fn(net, ops, nf_nat_ipv6_ops, ARRAY_SIZE(nf_nat_ipv6_ops)); -} -EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv6_register_fn); - -void nf_nat_l3proto_ipv6_unregister_fn(struct net *net, const struct nf_hook_ops *ops) -{ - nf_nat_unregister_fn(net, ops, ARRAY_SIZE(nf_nat_ipv6_ops)); -} -EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv6_unregister_fn); - -static int __init nf_nat_l3proto_ipv6_init(void) -{ - return nf_nat_l3proto_register(&nf_nat_l3proto_ipv6); -} - -static void __exit nf_nat_l3proto_ipv6_exit(void) -{ - nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv6); -} - -MODULE_LICENSE("GPL"); -MODULE_ALIAS("nf-nat-" __stringify(AF_INET6)); - -module_init(nf_nat_l3proto_ipv6_init); -module_exit(nf_nat_l3proto_ipv6_exit); diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index 5a753cec005b..5beb51d39dc2 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -396,7 +396,13 @@ config NETFILTER_NETLINK_GLUE_CT the enqueued via NFNETLINK. config NF_NAT - tristate + tristate "Network Address Translation support" + depends on NF_CONNTRACK + default m if NETFILTER_ADVANCED=n + help + The NAT option allows masquerading, port forwarding and other + forms of full Network Address Port Translation. This can be + controlled by iptables, ip6tables or nft. config NF_NAT_NEEDED bool diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index 0f39ae7a9f34..0c548ff215b2 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -1203,6 +1203,8 @@ static struct nf_nat_hook nat_hook = { .manip_pkt = nf_nat_manip_pkt, }; +int nf_nat_l3proto_init(void); +void nf_nat_l3proto_exit(void); static int __init nf_nat_init(void) { int ret, i; @@ -1237,6 +1239,19 @@ static int __init nf_nat_init(void) WARN_ON(nf_nat_hook != NULL); RCU_INIT_POINTER(nf_nat_hook, &nat_hook); + ret = nf_nat_l3proto_init(); + if (ret) { + nf_ct_extend_unregister(&nat_extend); + nf_ct_helper_expectfn_unregister(&follow_master_nat); + RCU_INIT_POINTER(nf_nat_hook, NULL); + + synchronize_net(); + kvfree(nf_nat_bysource); + unregister_pernet_subsys(&nat_net_ops); + + return ret; + } + return 0; } @@ -1246,6 +1261,8 @@ static void __exit nf_nat_cleanup(void) nf_ct_iterate_destroy(nf_nat_proto_clean, &clean); + nf_nat_l3proto_exit(); + nf_ct_extend_unregister(&nat_extend); nf_ct_helper_expectfn_unregister(&follow_master_nat); RCU_INIT_POINTER(nf_nat_hook, NULL); diff --git a/net/netfilter/nf_nat_proto.c b/net/netfilter/nf_nat_proto.c index f83bf9d8c9f5..9c4db18741ef 100644 --- a/net/netfilter/nf_nat_proto.c +++ b/net/netfilter/nf_nat_proto.c @@ -24,6 +24,22 @@ #include #include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +static const struct nf_nat_l3proto nf_nat_l3proto_ipv4; +#if IS_ENABLED(CONFIG_IPV6) +static const struct nf_nat_l3proto nf_nat_l3proto_ipv6; +#endif + static void __udp_manip_pkt(struct sk_buff *skb, const struct nf_nat_l3proto *l3proto, @@ -341,3 +357,665 @@ bool nf_nat_l4proto_manip_pkt(struct sk_buff *skb, return true; } EXPORT_SYMBOL_GPL(nf_nat_l4proto_manip_pkt); + +static bool nf_nat_ipv4_manip_pkt(struct sk_buff *skb, + unsigned int iphdroff, + const struct nf_conntrack_tuple *target, + enum nf_nat_manip_type maniptype) +{ + struct iphdr *iph; + unsigned int hdroff; + + if (!skb_make_writable(skb, iphdroff + sizeof(*iph))) + return false; + + iph = (void *)skb->data + iphdroff; + hdroff = iphdroff + iph->ihl * 4; + + if (!nf_nat_l4proto_manip_pkt(skb, &nf_nat_l3proto_ipv4, iphdroff, + hdroff, target, maniptype)) + return false; + iph = (void *)skb->data + iphdroff; + + if (maniptype == NF_NAT_MANIP_SRC) { + csum_replace4(&iph->check, iph->saddr, target->src.u3.ip); + iph->saddr = target->src.u3.ip; + } else { + csum_replace4(&iph->check, iph->daddr, target->dst.u3.ip); + iph->daddr = target->dst.u3.ip; + } + return true; +} + +static bool nf_nat_ipv6_manip_pkt(struct sk_buff *skb, + unsigned int iphdroff, + const struct nf_conntrack_tuple *target, + enum nf_nat_manip_type maniptype) +{ +#if IS_ENABLED(CONFIG_IPV6) + struct ipv6hdr *ipv6h; + __be16 frag_off; + int hdroff; + u8 nexthdr; + + if (!skb_make_writable(skb, iphdroff + sizeof(*ipv6h))) + return false; + + ipv6h = (void *)skb->data + iphdroff; + nexthdr = ipv6h->nexthdr; + hdroff = ipv6_skip_exthdr(skb, iphdroff + sizeof(*ipv6h), + &nexthdr, &frag_off); + if (hdroff < 0) + goto manip_addr; + + if ((frag_off & htons(~0x7)) == 0 && + !nf_nat_l4proto_manip_pkt(skb, &nf_nat_l3proto_ipv6, iphdroff, hdroff, + target, maniptype)) + return false; + + /* must reload, offset might have changed */ + ipv6h = (void *)skb->data + iphdroff; + +manip_addr: + if (maniptype == NF_NAT_MANIP_SRC) + ipv6h->saddr = target->src.u3.in6; + else + ipv6h->daddr = target->dst.u3.in6; + +#endif + return true; +} + +static void nf_nat_ipv4_csum_update(struct sk_buff *skb, + unsigned int iphdroff, __sum16 *check, + const struct nf_conntrack_tuple *t, + enum nf_nat_manip_type maniptype) +{ + struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff); + __be32 oldip, newip; + + if (maniptype == NF_NAT_MANIP_SRC) { + oldip = iph->saddr; + newip = t->src.u3.ip; + } else { + oldip = iph->daddr; + newip = t->dst.u3.ip; + } + inet_proto_csum_replace4(check, skb, oldip, newip, true); +} + +static void nf_nat_ipv6_csum_update(struct sk_buff *skb, + unsigned int iphdroff, __sum16 *check, + const struct nf_conntrack_tuple *t, + enum nf_nat_manip_type maniptype) +{ +#if IS_ENABLED(CONFIG_IPV6) + const struct ipv6hdr *ipv6h = (struct ipv6hdr *)(skb->data + iphdroff); + const struct in6_addr *oldip, *newip; + + if (maniptype == NF_NAT_MANIP_SRC) { + oldip = &ipv6h->saddr; + newip = &t->src.u3.in6; + } else { + oldip = &ipv6h->daddr; + newip = &t->dst.u3.in6; + } + inet_proto_csum_replace16(check, skb, oldip->s6_addr32, + newip->s6_addr32, true); +#endif +} + +static void nf_nat_ipv4_csum_recalc(struct sk_buff *skb, + u8 proto, void *data, __sum16 *check, + int datalen, int oldlen) +{ + if (skb->ip_summed != CHECKSUM_PARTIAL) { + const struct iphdr *iph = ip_hdr(skb); + + skb->ip_summed = CHECKSUM_PARTIAL; + skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) + + ip_hdrlen(skb); + skb->csum_offset = (void *)check - data; + *check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, datalen, + proto, 0); + } else { + inet_proto_csum_replace2(check, skb, + htons(oldlen), htons(datalen), true); + } +} + +#if IS_ENABLED(CONFIG_IPV6) +static void nf_nat_ipv6_csum_recalc(struct sk_buff *skb, + u8 proto, void *data, __sum16 *check, + int datalen, int oldlen) +{ + if (skb->ip_summed != CHECKSUM_PARTIAL) { + const struct ipv6hdr *ipv6h = ipv6_hdr(skb); + + skb->ip_summed = CHECKSUM_PARTIAL; + skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) + + (data - (void *)skb->data); + skb->csum_offset = (void *)check - data; + *check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, + datalen, proto, 0); + } else { + inet_proto_csum_replace2(check, skb, + htons(oldlen), htons(datalen), true); + } +} +#endif + +static const struct nf_nat_l3proto nf_nat_l3proto_ipv4 = { + .l3proto = NFPROTO_IPV4, + .manip_pkt = nf_nat_ipv4_manip_pkt, + .csum_update = nf_nat_ipv4_csum_update, + .csum_recalc = nf_nat_ipv4_csum_recalc, +}; + +int nf_nat_icmp_reply_translation(struct sk_buff *skb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned int hooknum) +{ + struct { + struct icmphdr icmp; + struct iphdr ip; + } *inside; + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + enum nf_nat_manip_type manip = HOOK2MANIP(hooknum); + unsigned int hdrlen = ip_hdrlen(skb); + struct nf_conntrack_tuple target; + unsigned long statusbit; + + WARN_ON(ctinfo != IP_CT_RELATED && ctinfo != IP_CT_RELATED_REPLY); + + if (!skb_make_writable(skb, hdrlen + sizeof(*inside))) + return 0; + if (nf_ip_checksum(skb, hooknum, hdrlen, 0)) + return 0; + + inside = (void *)skb->data + hdrlen; + if (inside->icmp.type == ICMP_REDIRECT) { + if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK) + return 0; + if (ct->status & IPS_NAT_MASK) + return 0; + } + + if (manip == NF_NAT_MANIP_SRC) + statusbit = IPS_SRC_NAT; + else + statusbit = IPS_DST_NAT; + + /* Invert if this is reply direction */ + if (dir == IP_CT_DIR_REPLY) + statusbit ^= IPS_NAT_MASK; + + if (!(ct->status & statusbit)) + return 1; + + if (!nf_nat_ipv4_manip_pkt(skb, hdrlen + sizeof(inside->icmp), + &ct->tuplehash[!dir].tuple, !manip)) + return 0; + + if (skb->ip_summed != CHECKSUM_PARTIAL) { + /* Reloading "inside" here since manip_pkt may reallocate */ + inside = (void *)skb->data + hdrlen; + inside->icmp.checksum = 0; + inside->icmp.checksum = + csum_fold(skb_checksum(skb, hdrlen, + skb->len - hdrlen, 0)); + } + + /* Change outer to look like the reply to an incoming packet */ + nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); + target.dst.protonum = IPPROTO_ICMP; + if (!nf_nat_ipv4_manip_pkt(skb, 0, &target, manip)) + return 0; + + return 1; +} +EXPORT_SYMBOL_GPL(nf_nat_icmp_reply_translation); + +static unsigned int +nf_nat_ipv4_fn(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + struct nf_conn *ct; + enum ip_conntrack_info ctinfo; + + ct = nf_ct_get(skb, &ctinfo); + if (!ct) + return NF_ACCEPT; + + if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_REPLY) { + if (ip_hdr(skb)->protocol == IPPROTO_ICMP) { + if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, + state->hook)) + return NF_DROP; + else + return NF_ACCEPT; + } + } + + return nf_nat_inet_fn(priv, skb, state); +} + +static unsigned int +nf_nat_ipv4_in(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + unsigned int ret; + __be32 daddr = ip_hdr(skb)->daddr; + + ret = nf_nat_ipv4_fn(priv, skb, state); + if (ret == NF_ACCEPT && daddr != ip_hdr(skb)->daddr) + skb_dst_drop(skb); + + return ret; +} + +static unsigned int +nf_nat_ipv4_out(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ +#ifdef CONFIG_XFRM + const struct nf_conn *ct; + enum ip_conntrack_info ctinfo; + int err; +#endif + unsigned int ret; + + ret = nf_nat_ipv4_fn(priv, skb, state); +#ifdef CONFIG_XFRM + if (ret != NF_ACCEPT) + return ret; + + if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) + return ret; + + ct = nf_ct_get(skb, &ctinfo); + if (ct) { + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + + if (ct->tuplehash[dir].tuple.src.u3.ip != + ct->tuplehash[!dir].tuple.dst.u3.ip || + (ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP && + ct->tuplehash[dir].tuple.src.u.all != + ct->tuplehash[!dir].tuple.dst.u.all)) { + err = nf_xfrm_me_harder(state->net, skb, AF_INET); + if (err < 0) + ret = NF_DROP_ERR(err); + } + } +#endif + return ret; +} + +static unsigned int +nf_nat_ipv4_local_fn(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + const struct nf_conn *ct; + enum ip_conntrack_info ctinfo; + unsigned int ret; + int err; + + ret = nf_nat_ipv4_fn(priv, skb, state); + if (ret != NF_ACCEPT) + return ret; + + ct = nf_ct_get(skb, &ctinfo); + if (ct) { + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + + if (ct->tuplehash[dir].tuple.dst.u3.ip != + ct->tuplehash[!dir].tuple.src.u3.ip) { + err = ip_route_me_harder(state->net, skb, RTN_UNSPEC); + if (err < 0) + ret = NF_DROP_ERR(err); + } +#ifdef CONFIG_XFRM + else if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) && + ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP && + ct->tuplehash[dir].tuple.dst.u.all != + ct->tuplehash[!dir].tuple.src.u.all) { + err = nf_xfrm_me_harder(state->net, skb, AF_INET); + if (err < 0) + ret = NF_DROP_ERR(err); + } +#endif + } + return ret; +} + +static const struct nf_hook_ops nf_nat_ipv4_ops[] = { + /* Before packet filtering, change destination */ + { + .hook = nf_nat_ipv4_in, + .pf = NFPROTO_IPV4, + .hooknum = NF_INET_PRE_ROUTING, + .priority = NF_IP_PRI_NAT_DST, + }, + /* After packet filtering, change source */ + { + .hook = nf_nat_ipv4_out, + .pf = NFPROTO_IPV4, + .hooknum = NF_INET_POST_ROUTING, + .priority = NF_IP_PRI_NAT_SRC, + }, + /* Before packet filtering, change destination */ + { + .hook = nf_nat_ipv4_local_fn, + .pf = NFPROTO_IPV4, + .hooknum = NF_INET_LOCAL_OUT, + .priority = NF_IP_PRI_NAT_DST, + }, + /* After packet filtering, change source */ + { + .hook = nf_nat_ipv4_fn, + .pf = NFPROTO_IPV4, + .hooknum = NF_INET_LOCAL_IN, + .priority = NF_IP_PRI_NAT_SRC, + }, +}; + +int nf_nat_l3proto_ipv4_register_fn(struct net *net, const struct nf_hook_ops *ops) +{ + return nf_nat_register_fn(net, ops, nf_nat_ipv4_ops, ARRAY_SIZE(nf_nat_ipv4_ops)); +} +EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_register_fn); + +void nf_nat_l3proto_ipv4_unregister_fn(struct net *net, const struct nf_hook_ops *ops) +{ + nf_nat_unregister_fn(net, ops, ARRAY_SIZE(nf_nat_ipv4_ops)); +} +EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_unregister_fn); + +int nf_nat_l3proto_init(void) +{ + int ret = nf_nat_l3proto_register(&nf_nat_l3proto_ipv4); + +#if IS_ENABLED(CONFIG_IPV6) + if (ret) + return ret; + + ret = nf_nat_l3proto_register(&nf_nat_l3proto_ipv6); + if (ret == 0) + return ret; + + nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv4); +#endif + return ret; +} + +void nf_nat_l3proto_exit(void) +{ +#if IS_ENABLED(CONFIG_IPV6) + nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv6); +#endif + nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv4); +} + +#if IS_ENABLED(CONFIG_IPV6) +static const struct nf_nat_l3proto nf_nat_l3proto_ipv6; + +static const struct nf_nat_l3proto nf_nat_l3proto_ipv6 = { + .l3proto = NFPROTO_IPV6, + .manip_pkt = nf_nat_ipv6_manip_pkt, + .csum_update = nf_nat_ipv6_csum_update, + .csum_recalc = nf_nat_ipv6_csum_recalc, +}; + +int nf_nat_icmpv6_reply_translation(struct sk_buff *skb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned int hooknum, + unsigned int hdrlen) +{ + struct { + struct icmp6hdr icmp6; + struct ipv6hdr ip6; + } *inside; + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + enum nf_nat_manip_type manip = HOOK2MANIP(hooknum); + struct nf_conntrack_tuple target; + unsigned long statusbit; + + WARN_ON(ctinfo != IP_CT_RELATED && ctinfo != IP_CT_RELATED_REPLY); + + if (!skb_make_writable(skb, hdrlen + sizeof(*inside))) + return 0; + if (nf_ip6_checksum(skb, hooknum, hdrlen, IPPROTO_ICMPV6)) + return 0; + + inside = (void *)skb->data + hdrlen; + if (inside->icmp6.icmp6_type == NDISC_REDIRECT) { + if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK) + return 0; + if (ct->status & IPS_NAT_MASK) + return 0; + } + + if (manip == NF_NAT_MANIP_SRC) + statusbit = IPS_SRC_NAT; + else + statusbit = IPS_DST_NAT; + + /* Invert if this is reply direction */ + if (dir == IP_CT_DIR_REPLY) + statusbit ^= IPS_NAT_MASK; + + if (!(ct->status & statusbit)) + return 1; + + if (!nf_nat_ipv6_manip_pkt(skb, hdrlen + sizeof(inside->icmp6), + &ct->tuplehash[!dir].tuple, !manip)) + return 0; + + if (skb->ip_summed != CHECKSUM_PARTIAL) { + struct ipv6hdr *ipv6h = ipv6_hdr(skb); + + inside = (void *)skb->data + hdrlen; + inside->icmp6.icmp6_cksum = 0; + inside->icmp6.icmp6_cksum = + csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, + skb->len - hdrlen, IPPROTO_ICMPV6, + skb_checksum(skb, hdrlen, + skb->len - hdrlen, 0)); + } + + nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); + target.dst.protonum = IPPROTO_ICMPV6; + if (!nf_nat_ipv6_manip_pkt(skb, 0, &target, manip)) + return 0; + + return 1; +} +EXPORT_SYMBOL_GPL(nf_nat_icmpv6_reply_translation); + +static unsigned int +nf_nat_ipv6_fn(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + struct nf_conn *ct; + enum ip_conntrack_info ctinfo; + __be16 frag_off; + int hdrlen; + u8 nexthdr; + + ct = nf_ct_get(skb, &ctinfo); + /* Can't track? It's not due to stress, or conntrack would + * have dropped it. Hence it's the user's responsibilty to + * packet filter it out, or implement conntrack/NAT for that + * protocol. 8) --RR + */ + if (!ct) + return NF_ACCEPT; + + if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_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, + state->hook, + hdrlen)) + return NF_DROP; + else + return NF_ACCEPT; + } + } + + return nf_nat_inet_fn(priv, skb, state); +} + +static unsigned int +nf_nat_ipv6_in(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + unsigned int ret; + struct in6_addr daddr = ipv6_hdr(skb)->daddr; + + ret = nf_nat_ipv6_fn(priv, skb, state); + 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_out(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ +#ifdef CONFIG_XFRM + const struct nf_conn *ct; + enum ip_conntrack_info ctinfo; + int err; +#endif + unsigned int ret; + + ret = nf_nat_ipv6_fn(priv, skb, state); +#ifdef CONFIG_XFRM + if (ret != NF_ACCEPT) + return ret; + + if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) + return ret; + ct = nf_ct_get(skb, &ctinfo); + if (ct) { + 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.dst.protonum != IPPROTO_ICMPV6 && + ct->tuplehash[dir].tuple.src.u.all != + ct->tuplehash[!dir].tuple.dst.u.all)) { + err = nf_xfrm_me_harder(state->net, skb, AF_INET6); + if (err < 0) + ret = NF_DROP_ERR(err); + } + } +#endif + + return ret; +} + +static int nat_route_me_harder(struct net *net, struct sk_buff *skb) +{ +#ifdef CONFIG_IPV6_MODULE + const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops(); + + if (!v6_ops) + return -EHOSTUNREACH; + + return v6_ops->route_me_harder(net, skb); +#else + return ip6_route_me_harder(net, skb); +#endif +} + +static unsigned int +nf_nat_ipv6_local_fn(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + const struct nf_conn *ct; + enum ip_conntrack_info ctinfo; + unsigned int ret; + int err; + + ret = nf_nat_ipv6_fn(priv, skb, state); + if (ret != NF_ACCEPT) + return ret; + + ct = nf_ct_get(skb, &ctinfo); + if (ct) { + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + + if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3, + &ct->tuplehash[!dir].tuple.src.u3)) { + err = nat_route_me_harder(state->net, skb); + if (err < 0) + ret = NF_DROP_ERR(err); + } +#ifdef CONFIG_XFRM + else if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && + ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMPV6 && + ct->tuplehash[dir].tuple.dst.u.all != + ct->tuplehash[!dir].tuple.src.u.all) { + err = nf_xfrm_me_harder(state->net, skb, AF_INET6); + if (err < 0) + ret = NF_DROP_ERR(err); + } +#endif + } + + return ret; +} + +static const struct nf_hook_ops nf_nat_ipv6_ops[] = { + /* Before packet filtering, change destination */ + { + .hook = nf_nat_ipv6_in, + .pf = NFPROTO_IPV6, + .hooknum = NF_INET_PRE_ROUTING, + .priority = NF_IP6_PRI_NAT_DST, + }, + /* After packet filtering, change source */ + { + .hook = nf_nat_ipv6_out, + .pf = NFPROTO_IPV6, + .hooknum = NF_INET_POST_ROUTING, + .priority = NF_IP6_PRI_NAT_SRC, + }, + /* Before packet filtering, change destination */ + { + .hook = nf_nat_ipv6_local_fn, + .pf = NFPROTO_IPV6, + .hooknum = NF_INET_LOCAL_OUT, + .priority = NF_IP6_PRI_NAT_DST, + }, + /* After packet filtering, change source */ + { + .hook = nf_nat_ipv6_fn, + .pf = NFPROTO_IPV6, + .hooknum = NF_INET_LOCAL_IN, + .priority = NF_IP6_PRI_NAT_SRC, + }, +}; + +int nf_nat_l3proto_ipv6_register_fn(struct net *net, const struct nf_hook_ops *ops) +{ + return nf_nat_register_fn(net, ops, nf_nat_ipv6_ops, + ARRAY_SIZE(nf_nat_ipv6_ops)); +} +EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv6_register_fn); + +void nf_nat_l3proto_ipv6_unregister_fn(struct net *net, const struct nf_hook_ops *ops) +{ + nf_nat_unregister_fn(net, ops, ARRAY_SIZE(nf_nat_ipv6_ops)); +} +EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv6_unregister_fn); +#endif /* CONFIG_IPV6 */ diff --git a/net/openvswitch/Kconfig b/net/openvswitch/Kconfig index 89da9512ec1e..ac1cc6e38170 100644 --- a/net/openvswitch/Kconfig +++ b/net/openvswitch/Kconfig @@ -8,8 +8,6 @@ config OPENVSWITCH depends on !NF_CONNTRACK || \ (NF_CONNTRACK && ((!NF_DEFRAG_IPV6 || NF_DEFRAG_IPV6) && \ (!NF_NAT || NF_NAT) && \ - (!NF_NAT_IPV4 || NF_NAT_IPV4) && \ - (!NF_NAT_IPV6 || NF_NAT_IPV6) && \ (!NETFILTER_CONNCOUNT || NETFILTER_CONNCOUNT))) select LIBCRC32C select MPLS diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c index 35884f836260..def4d28fcbc3 100644 --- a/net/openvswitch/conntrack.c +++ b/net/openvswitch/conntrack.c @@ -745,14 +745,14 @@ static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, switch (ctinfo) { case IP_CT_RELATED: case IP_CT_RELATED_REPLY: - if (IS_ENABLED(CONFIG_NF_NAT_IPV4) && + if (IS_ENABLED(CONFIG_NF_NAT) && skb->protocol == htons(ETH_P_IP) && ip_hdr(skb)->protocol == IPPROTO_ICMP) { if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, hooknum)) err = NF_DROP; goto push; - } else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) && + } else if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) { __be16 frag_off; u8 nexthdr = ipv6_hdr(skb)->nexthdr; @@ -1673,7 +1673,7 @@ static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, } if (info->range.flags & NF_NAT_RANGE_MAP_IPS) { - if (IS_ENABLED(CONFIG_NF_NAT_IPV4) && + if (IS_ENABLED(CONFIG_NF_NAT) && info->family == NFPROTO_IPV4) { if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN, info->range.min_addr.ip) || @@ -1682,7 +1682,7 @@ static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX, info->range.max_addr.ip)))) return false; - } else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) && + } else if (IS_ENABLED(CONFIG_IPV6) && info->family == NFPROTO_IPV6) { if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN, &info->range.min_addr.in6) || diff --git a/tools/testing/selftests/net/config b/tools/testing/selftests/net/config index 5821bdd98d20..e9c860d00416 100644 --- a/tools/testing/selftests/net/config +++ b/tools/testing/selftests/net/config @@ -17,8 +17,7 @@ CONFIG_VLAN_8021Q=y CONFIG_NETFILTER=y CONFIG_NETFILTER_ADVANCED=y CONFIG_NF_CONNTRACK=m -CONFIG_NF_NAT_IPV6=m -CONFIG_NF_NAT_IPV4=m +CONFIG_NF_NAT=m CONFIG_IP6_NF_IPTABLES=m CONFIG_IP_NF_IPTABLES=m CONFIG_IP6_NF_NAT=m