![Johannes Berg](/assets/img/avatar_default.png)
We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1210 lines
32 KiB
C
1210 lines
32 KiB
C
/*
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* (C) 1999-2001 Paul `Rusty' Russell
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* (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
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* (C) 2011 Patrick McHardy <kaber@trash.net>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/timer.h>
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#include <linux/skbuff.h>
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#include <linux/gfp.h>
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#include <net/xfrm.h>
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#include <linux/jhash.h>
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#include <linux/rtnetlink.h>
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_conntrack_core.h>
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#include <net/netfilter/nf_nat.h>
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#include <net/netfilter/nf_nat_helper.h>
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#include <net/netfilter/nf_conntrack_helper.h>
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#include <net/netfilter/nf_conntrack_seqadj.h>
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#include <net/netfilter/nf_conntrack_zones.h>
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#include <linux/netfilter/nf_nat.h>
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#include "nf_internals.h"
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static spinlock_t nf_nat_locks[CONNTRACK_LOCKS];
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static DEFINE_MUTEX(nf_nat_proto_mutex);
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static unsigned int nat_net_id __read_mostly;
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static struct hlist_head *nf_nat_bysource __read_mostly;
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static unsigned int nf_nat_htable_size __read_mostly;
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static unsigned int nf_nat_hash_rnd __read_mostly;
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struct nf_nat_lookup_hook_priv {
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struct nf_hook_entries __rcu *entries;
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struct rcu_head rcu_head;
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};
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struct nf_nat_hooks_net {
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struct nf_hook_ops *nat_hook_ops;
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unsigned int users;
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};
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struct nat_net {
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struct nf_nat_hooks_net nat_proto_net[NFPROTO_NUMPROTO];
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};
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#ifdef CONFIG_XFRM
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static void nf_nat_ipv4_decode_session(struct sk_buff *skb,
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const struct nf_conn *ct,
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enum ip_conntrack_dir dir,
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unsigned long statusbit,
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struct flowi *fl)
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{
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const struct nf_conntrack_tuple *t = &ct->tuplehash[dir].tuple;
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struct flowi4 *fl4 = &fl->u.ip4;
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if (ct->status & statusbit) {
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fl4->daddr = t->dst.u3.ip;
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if (t->dst.protonum == IPPROTO_TCP ||
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t->dst.protonum == IPPROTO_UDP ||
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t->dst.protonum == IPPROTO_UDPLITE ||
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t->dst.protonum == IPPROTO_DCCP ||
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t->dst.protonum == IPPROTO_SCTP)
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fl4->fl4_dport = t->dst.u.all;
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}
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statusbit ^= IPS_NAT_MASK;
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if (ct->status & statusbit) {
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fl4->saddr = t->src.u3.ip;
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if (t->dst.protonum == IPPROTO_TCP ||
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t->dst.protonum == IPPROTO_UDP ||
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t->dst.protonum == IPPROTO_UDPLITE ||
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t->dst.protonum == IPPROTO_DCCP ||
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t->dst.protonum == IPPROTO_SCTP)
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fl4->fl4_sport = t->src.u.all;
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}
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}
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static void nf_nat_ipv6_decode_session(struct sk_buff *skb,
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const struct nf_conn *ct,
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enum ip_conntrack_dir dir,
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unsigned long statusbit,
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struct flowi *fl)
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{
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#if IS_ENABLED(CONFIG_IPV6)
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const struct nf_conntrack_tuple *t = &ct->tuplehash[dir].tuple;
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struct flowi6 *fl6 = &fl->u.ip6;
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if (ct->status & statusbit) {
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fl6->daddr = t->dst.u3.in6;
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if (t->dst.protonum == IPPROTO_TCP ||
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t->dst.protonum == IPPROTO_UDP ||
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t->dst.protonum == IPPROTO_UDPLITE ||
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t->dst.protonum == IPPROTO_DCCP ||
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t->dst.protonum == IPPROTO_SCTP)
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fl6->fl6_dport = t->dst.u.all;
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}
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statusbit ^= IPS_NAT_MASK;
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if (ct->status & statusbit) {
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fl6->saddr = t->src.u3.in6;
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if (t->dst.protonum == IPPROTO_TCP ||
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t->dst.protonum == IPPROTO_UDP ||
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t->dst.protonum == IPPROTO_UDPLITE ||
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t->dst.protonum == IPPROTO_DCCP ||
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t->dst.protonum == IPPROTO_SCTP)
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fl6->fl6_sport = t->src.u.all;
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}
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#endif
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}
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static void __nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl)
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{
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const struct nf_conn *ct;
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enum ip_conntrack_info ctinfo;
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enum ip_conntrack_dir dir;
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unsigned long statusbit;
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u8 family;
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ct = nf_ct_get(skb, &ctinfo);
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if (ct == NULL)
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return;
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family = nf_ct_l3num(ct);
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dir = CTINFO2DIR(ctinfo);
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if (dir == IP_CT_DIR_ORIGINAL)
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statusbit = IPS_DST_NAT;
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else
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statusbit = IPS_SRC_NAT;
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switch (family) {
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case NFPROTO_IPV4:
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nf_nat_ipv4_decode_session(skb, ct, dir, statusbit, fl);
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return;
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case NFPROTO_IPV6:
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nf_nat_ipv6_decode_session(skb, ct, dir, statusbit, fl);
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return;
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}
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}
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int nf_xfrm_me_harder(struct net *net, struct sk_buff *skb, unsigned int family)
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{
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struct flowi fl;
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unsigned int hh_len;
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struct dst_entry *dst;
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struct sock *sk = skb->sk;
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int err;
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err = xfrm_decode_session(skb, &fl, family);
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if (err < 0)
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return err;
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dst = skb_dst(skb);
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if (dst->xfrm)
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dst = ((struct xfrm_dst *)dst)->route;
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if (!dst_hold_safe(dst))
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return -EHOSTUNREACH;
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if (sk && !net_eq(net, sock_net(sk)))
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sk = NULL;
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dst = xfrm_lookup(net, dst, &fl, sk, 0);
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if (IS_ERR(dst))
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return PTR_ERR(dst);
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skb_dst_drop(skb);
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skb_dst_set(skb, dst);
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/* Change in oif may mean change in hh_len. */
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hh_len = skb_dst(skb)->dev->hard_header_len;
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if (skb_headroom(skb) < hh_len &&
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pskb_expand_head(skb, hh_len - skb_headroom(skb), 0, GFP_ATOMIC))
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return -ENOMEM;
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return 0;
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}
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EXPORT_SYMBOL(nf_xfrm_me_harder);
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#endif /* CONFIG_XFRM */
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/* We keep an extra hash for each conntrack, for fast searching. */
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static unsigned int
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hash_by_src(const struct net *n, const struct nf_conntrack_tuple *tuple)
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{
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unsigned int hash;
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get_random_once(&nf_nat_hash_rnd, sizeof(nf_nat_hash_rnd));
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/* Original src, to ensure we map it consistently if poss. */
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hash = jhash2((u32 *)&tuple->src, sizeof(tuple->src) / sizeof(u32),
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tuple->dst.protonum ^ nf_nat_hash_rnd ^ net_hash_mix(n));
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return reciprocal_scale(hash, nf_nat_htable_size);
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}
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/* Is this tuple already taken? (not by us) */
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static int
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nf_nat_used_tuple(const struct nf_conntrack_tuple *tuple,
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const struct nf_conn *ignored_conntrack)
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{
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/* Conntrack tracking doesn't keep track of outgoing tuples; only
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* incoming ones. NAT means they don't have a fixed mapping,
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* so we invert the tuple and look for the incoming reply.
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*
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* We could keep a separate hash if this proves too slow.
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*/
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struct nf_conntrack_tuple reply;
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nf_ct_invert_tuple(&reply, tuple);
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return nf_conntrack_tuple_taken(&reply, ignored_conntrack);
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}
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static bool nf_nat_inet_in_range(const struct nf_conntrack_tuple *t,
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const struct nf_nat_range2 *range)
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{
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if (t->src.l3num == NFPROTO_IPV4)
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return ntohl(t->src.u3.ip) >= ntohl(range->min_addr.ip) &&
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ntohl(t->src.u3.ip) <= ntohl(range->max_addr.ip);
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return ipv6_addr_cmp(&t->src.u3.in6, &range->min_addr.in6) >= 0 &&
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ipv6_addr_cmp(&t->src.u3.in6, &range->max_addr.in6) <= 0;
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}
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/* Is the manipable part of the tuple between min and max incl? */
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static bool l4proto_in_range(const struct nf_conntrack_tuple *tuple,
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enum nf_nat_manip_type maniptype,
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const union nf_conntrack_man_proto *min,
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const union nf_conntrack_man_proto *max)
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{
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__be16 port;
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switch (tuple->dst.protonum) {
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case IPPROTO_ICMP:
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case IPPROTO_ICMPV6:
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return ntohs(tuple->src.u.icmp.id) >= ntohs(min->icmp.id) &&
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ntohs(tuple->src.u.icmp.id) <= ntohs(max->icmp.id);
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case IPPROTO_GRE: /* all fall though */
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case IPPROTO_TCP:
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case IPPROTO_UDP:
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case IPPROTO_UDPLITE:
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case IPPROTO_DCCP:
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case IPPROTO_SCTP:
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if (maniptype == NF_NAT_MANIP_SRC)
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port = tuple->src.u.all;
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else
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port = tuple->dst.u.all;
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return ntohs(port) >= ntohs(min->all) &&
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ntohs(port) <= ntohs(max->all);
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default:
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return true;
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}
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}
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/* If we source map this tuple so reply looks like reply_tuple, will
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* that meet the constraints of range.
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*/
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static int in_range(const struct nf_conntrack_tuple *tuple,
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const struct nf_nat_range2 *range)
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{
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/* If we are supposed to map IPs, then we must be in the
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* range specified, otherwise let this drag us onto a new src IP.
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*/
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if (range->flags & NF_NAT_RANGE_MAP_IPS &&
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!nf_nat_inet_in_range(tuple, range))
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return 0;
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if (!(range->flags & NF_NAT_RANGE_PROTO_SPECIFIED))
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return 1;
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return l4proto_in_range(tuple, NF_NAT_MANIP_SRC,
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&range->min_proto, &range->max_proto);
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}
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static inline int
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same_src(const struct nf_conn *ct,
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const struct nf_conntrack_tuple *tuple)
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{
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const struct nf_conntrack_tuple *t;
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t = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
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return (t->dst.protonum == tuple->dst.protonum &&
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nf_inet_addr_cmp(&t->src.u3, &tuple->src.u3) &&
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t->src.u.all == tuple->src.u.all);
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}
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/* Only called for SRC manip */
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static int
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find_appropriate_src(struct net *net,
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const struct nf_conntrack_zone *zone,
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const struct nf_conntrack_tuple *tuple,
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struct nf_conntrack_tuple *result,
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const struct nf_nat_range2 *range)
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{
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unsigned int h = hash_by_src(net, tuple);
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const struct nf_conn *ct;
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hlist_for_each_entry_rcu(ct, &nf_nat_bysource[h], nat_bysource) {
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if (same_src(ct, tuple) &&
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net_eq(net, nf_ct_net(ct)) &&
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nf_ct_zone_equal(ct, zone, IP_CT_DIR_ORIGINAL)) {
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/* Copy source part from reply tuple. */
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nf_ct_invert_tuple(result,
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&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
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result->dst = tuple->dst;
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if (in_range(result, range))
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return 1;
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}
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}
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return 0;
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}
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/* For [FUTURE] fragmentation handling, we want the least-used
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* src-ip/dst-ip/proto triple. Fairness doesn't come into it. Thus
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* if the range specifies 1.2.3.4 ports 10000-10005 and 1.2.3.5 ports
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* 1-65535, we don't do pro-rata allocation based on ports; we choose
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* the ip with the lowest src-ip/dst-ip/proto usage.
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*/
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static void
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find_best_ips_proto(const struct nf_conntrack_zone *zone,
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struct nf_conntrack_tuple *tuple,
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const struct nf_nat_range2 *range,
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const struct nf_conn *ct,
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enum nf_nat_manip_type maniptype)
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{
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union nf_inet_addr *var_ipp;
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unsigned int i, max;
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/* Host order */
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u32 minip, maxip, j, dist;
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bool full_range;
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/* No IP mapping? Do nothing. */
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if (!(range->flags & NF_NAT_RANGE_MAP_IPS))
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return;
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if (maniptype == NF_NAT_MANIP_SRC)
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var_ipp = &tuple->src.u3;
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else
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var_ipp = &tuple->dst.u3;
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/* Fast path: only one choice. */
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if (nf_inet_addr_cmp(&range->min_addr, &range->max_addr)) {
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*var_ipp = range->min_addr;
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return;
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}
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if (nf_ct_l3num(ct) == NFPROTO_IPV4)
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max = sizeof(var_ipp->ip) / sizeof(u32) - 1;
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else
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max = sizeof(var_ipp->ip6) / sizeof(u32) - 1;
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/* Hashing source and destination IPs gives a fairly even
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* spread in practice (if there are a small number of IPs
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* involved, there usually aren't that many connections
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* anyway). The consistency means that servers see the same
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* client coming from the same IP (some Internet Banking sites
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* like this), even across reboots.
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*/
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j = jhash2((u32 *)&tuple->src.u3, sizeof(tuple->src.u3) / sizeof(u32),
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range->flags & NF_NAT_RANGE_PERSISTENT ?
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0 : (__force u32)tuple->dst.u3.all[max] ^ zone->id);
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full_range = false;
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for (i = 0; i <= max; i++) {
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/* If first bytes of the address are at the maximum, use the
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* distance. Otherwise use the full range.
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*/
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if (!full_range) {
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minip = ntohl((__force __be32)range->min_addr.all[i]);
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maxip = ntohl((__force __be32)range->max_addr.all[i]);
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dist = maxip - minip + 1;
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} else {
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minip = 0;
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dist = ~0;
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}
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var_ipp->all[i] = (__force __u32)
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htonl(minip + reciprocal_scale(j, dist));
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if (var_ipp->all[i] != range->max_addr.all[i])
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full_range = true;
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if (!(range->flags & NF_NAT_RANGE_PERSISTENT))
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j ^= (__force u32)tuple->dst.u3.all[i];
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}
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}
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/* Alter the per-proto part of the tuple (depending on maniptype), to
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* give a unique tuple in the given range if possible.
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*
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* Per-protocol part of tuple is initialized to the incoming packet.
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*/
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static void nf_nat_l4proto_unique_tuple(struct nf_conntrack_tuple *tuple,
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const struct nf_nat_range2 *range,
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enum nf_nat_manip_type maniptype,
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const struct nf_conn *ct)
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{
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unsigned int range_size, min, max, i, attempts;
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__be16 *keyptr;
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u16 off;
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static const unsigned int max_attempts = 128;
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switch (tuple->dst.protonum) {
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case IPPROTO_ICMP: /* fallthrough */
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case IPPROTO_ICMPV6:
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/* id is same for either direction... */
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keyptr = &tuple->src.u.icmp.id;
|
|
if (!(range->flags & NF_NAT_RANGE_PROTO_SPECIFIED)) {
|
|
min = 0;
|
|
range_size = 65536;
|
|
} else {
|
|
min = ntohs(range->min_proto.icmp.id);
|
|
range_size = ntohs(range->max_proto.icmp.id) -
|
|
ntohs(range->min_proto.icmp.id) + 1;
|
|
}
|
|
goto find_free_id;
|
|
#if IS_ENABLED(CONFIG_NF_CT_PROTO_GRE)
|
|
case IPPROTO_GRE:
|
|
/* If there is no master conntrack we are not PPTP,
|
|
do not change tuples */
|
|
if (!ct->master)
|
|
return;
|
|
|
|
if (maniptype == NF_NAT_MANIP_SRC)
|
|
keyptr = &tuple->src.u.gre.key;
|
|
else
|
|
keyptr = &tuple->dst.u.gre.key;
|
|
|
|
if (!(range->flags & NF_NAT_RANGE_PROTO_SPECIFIED)) {
|
|
min = 1;
|
|
range_size = 65535;
|
|
} else {
|
|
min = ntohs(range->min_proto.gre.key);
|
|
range_size = ntohs(range->max_proto.gre.key) - min + 1;
|
|
}
|
|
goto find_free_id;
|
|
#endif
|
|
case IPPROTO_UDP: /* fallthrough */
|
|
case IPPROTO_UDPLITE: /* fallthrough */
|
|
case IPPROTO_TCP: /* fallthrough */
|
|
case IPPROTO_SCTP: /* fallthrough */
|
|
case IPPROTO_DCCP: /* fallthrough */
|
|
if (maniptype == NF_NAT_MANIP_SRC)
|
|
keyptr = &tuple->src.u.all;
|
|
else
|
|
keyptr = &tuple->dst.u.all;
|
|
|
|
break;
|
|
default:
|
|
return;
|
|
}
|
|
|
|
/* If no range specified... */
|
|
if (!(range->flags & NF_NAT_RANGE_PROTO_SPECIFIED)) {
|
|
/* If it's dst rewrite, can't change port */
|
|
if (maniptype == NF_NAT_MANIP_DST)
|
|
return;
|
|
|
|
if (ntohs(*keyptr) < 1024) {
|
|
/* Loose convention: >> 512 is credential passing */
|
|
if (ntohs(*keyptr) < 512) {
|
|
min = 1;
|
|
range_size = 511 - min + 1;
|
|
} else {
|
|
min = 600;
|
|
range_size = 1023 - min + 1;
|
|
}
|
|
} else {
|
|
min = 1024;
|
|
range_size = 65535 - 1024 + 1;
|
|
}
|
|
} else {
|
|
min = ntohs(range->min_proto.all);
|
|
max = ntohs(range->max_proto.all);
|
|
if (unlikely(max < min))
|
|
swap(max, min);
|
|
range_size = max - min + 1;
|
|
}
|
|
|
|
find_free_id:
|
|
if (range->flags & NF_NAT_RANGE_PROTO_OFFSET)
|
|
off = (ntohs(*keyptr) - ntohs(range->base_proto.all));
|
|
else
|
|
off = prandom_u32();
|
|
|
|
attempts = range_size;
|
|
if (attempts > max_attempts)
|
|
attempts = max_attempts;
|
|
|
|
/* We are in softirq; doing a search of the entire range risks
|
|
* soft lockup when all tuples are already used.
|
|
*
|
|
* If we can't find any free port from first offset, pick a new
|
|
* one and try again, with ever smaller search window.
|
|
*/
|
|
another_round:
|
|
for (i = 0; i < attempts; i++, off++) {
|
|
*keyptr = htons(min + off % range_size);
|
|
if (!nf_nat_used_tuple(tuple, ct))
|
|
return;
|
|
}
|
|
|
|
if (attempts >= range_size || attempts < 16)
|
|
return;
|
|
attempts /= 2;
|
|
off = prandom_u32();
|
|
goto another_round;
|
|
}
|
|
|
|
/* Manipulate the tuple into the range given. For NF_INET_POST_ROUTING,
|
|
* we change the source to map into the range. For NF_INET_PRE_ROUTING
|
|
* and NF_INET_LOCAL_OUT, we change the destination to map into the
|
|
* range. It might not be possible to get a unique tuple, but we try.
|
|
* At worst (or if we race), we will end up with a final duplicate in
|
|
* __ip_conntrack_confirm and drop the packet. */
|
|
static void
|
|
get_unique_tuple(struct nf_conntrack_tuple *tuple,
|
|
const struct nf_conntrack_tuple *orig_tuple,
|
|
const struct nf_nat_range2 *range,
|
|
struct nf_conn *ct,
|
|
enum nf_nat_manip_type maniptype)
|
|
{
|
|
const struct nf_conntrack_zone *zone;
|
|
struct net *net = nf_ct_net(ct);
|
|
|
|
zone = nf_ct_zone(ct);
|
|
|
|
/* 1) If this srcip/proto/src-proto-part is currently mapped,
|
|
* and that same mapping gives a unique tuple within the given
|
|
* range, use that.
|
|
*
|
|
* This is only required for source (ie. NAT/masq) mappings.
|
|
* So far, we don't do local source mappings, so multiple
|
|
* manips not an issue.
|
|
*/
|
|
if (maniptype == NF_NAT_MANIP_SRC &&
|
|
!(range->flags & NF_NAT_RANGE_PROTO_RANDOM_ALL)) {
|
|
/* try the original tuple first */
|
|
if (in_range(orig_tuple, range)) {
|
|
if (!nf_nat_used_tuple(orig_tuple, ct)) {
|
|
*tuple = *orig_tuple;
|
|
return;
|
|
}
|
|
} else if (find_appropriate_src(net, zone,
|
|
orig_tuple, tuple, range)) {
|
|
pr_debug("get_unique_tuple: Found current src map\n");
|
|
if (!nf_nat_used_tuple(tuple, ct))
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* 2) Select the least-used IP/proto combination in the given range */
|
|
*tuple = *orig_tuple;
|
|
find_best_ips_proto(zone, tuple, range, ct, maniptype);
|
|
|
|
/* 3) The per-protocol part of the manip is made to map into
|
|
* the range to make a unique tuple.
|
|
*/
|
|
|
|
/* Only bother mapping if it's not already in range and unique */
|
|
if (!(range->flags & NF_NAT_RANGE_PROTO_RANDOM_ALL)) {
|
|
if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
|
|
if (!(range->flags & NF_NAT_RANGE_PROTO_OFFSET) &&
|
|
l4proto_in_range(tuple, maniptype,
|
|
&range->min_proto,
|
|
&range->max_proto) &&
|
|
(range->min_proto.all == range->max_proto.all ||
|
|
!nf_nat_used_tuple(tuple, ct)))
|
|
return;
|
|
} else if (!nf_nat_used_tuple(tuple, ct)) {
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* Last chance: get protocol to try to obtain unique tuple. */
|
|
nf_nat_l4proto_unique_tuple(tuple, range, maniptype, ct);
|
|
}
|
|
|
|
struct nf_conn_nat *nf_ct_nat_ext_add(struct nf_conn *ct)
|
|
{
|
|
struct nf_conn_nat *nat = nfct_nat(ct);
|
|
if (nat)
|
|
return nat;
|
|
|
|
if (!nf_ct_is_confirmed(ct))
|
|
nat = nf_ct_ext_add(ct, NF_CT_EXT_NAT, GFP_ATOMIC);
|
|
|
|
return nat;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_nat_ext_add);
|
|
|
|
unsigned int
|
|
nf_nat_setup_info(struct nf_conn *ct,
|
|
const struct nf_nat_range2 *range,
|
|
enum nf_nat_manip_type maniptype)
|
|
{
|
|
struct net *net = nf_ct_net(ct);
|
|
struct nf_conntrack_tuple curr_tuple, new_tuple;
|
|
|
|
/* Can't setup nat info for confirmed ct. */
|
|
if (nf_ct_is_confirmed(ct))
|
|
return NF_ACCEPT;
|
|
|
|
WARN_ON(maniptype != NF_NAT_MANIP_SRC &&
|
|
maniptype != NF_NAT_MANIP_DST);
|
|
|
|
if (WARN_ON(nf_nat_initialized(ct, maniptype)))
|
|
return NF_DROP;
|
|
|
|
/* What we've got will look like inverse of reply. Normally
|
|
* this is what is in the conntrack, except for prior
|
|
* manipulations (future optimization: if num_manips == 0,
|
|
* orig_tp = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
|
|
*/
|
|
nf_ct_invert_tuple(&curr_tuple,
|
|
&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
|
|
|
|
get_unique_tuple(&new_tuple, &curr_tuple, range, ct, maniptype);
|
|
|
|
if (!nf_ct_tuple_equal(&new_tuple, &curr_tuple)) {
|
|
struct nf_conntrack_tuple reply;
|
|
|
|
/* Alter conntrack table so will recognize replies. */
|
|
nf_ct_invert_tuple(&reply, &new_tuple);
|
|
nf_conntrack_alter_reply(ct, &reply);
|
|
|
|
/* Non-atomic: we own this at the moment. */
|
|
if (maniptype == NF_NAT_MANIP_SRC)
|
|
ct->status |= IPS_SRC_NAT;
|
|
else
|
|
ct->status |= IPS_DST_NAT;
|
|
|
|
if (nfct_help(ct) && !nfct_seqadj(ct))
|
|
if (!nfct_seqadj_ext_add(ct))
|
|
return NF_DROP;
|
|
}
|
|
|
|
if (maniptype == NF_NAT_MANIP_SRC) {
|
|
unsigned int srchash;
|
|
spinlock_t *lock;
|
|
|
|
srchash = hash_by_src(net,
|
|
&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
|
|
lock = &nf_nat_locks[srchash % CONNTRACK_LOCKS];
|
|
spin_lock_bh(lock);
|
|
hlist_add_head_rcu(&ct->nat_bysource,
|
|
&nf_nat_bysource[srchash]);
|
|
spin_unlock_bh(lock);
|
|
}
|
|
|
|
/* It's done. */
|
|
if (maniptype == NF_NAT_MANIP_DST)
|
|
ct->status |= IPS_DST_NAT_DONE;
|
|
else
|
|
ct->status |= IPS_SRC_NAT_DONE;
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
EXPORT_SYMBOL(nf_nat_setup_info);
|
|
|
|
static unsigned int
|
|
__nf_nat_alloc_null_binding(struct nf_conn *ct, enum nf_nat_manip_type manip)
|
|
{
|
|
/* Force range to this IP; let proto decide mapping for
|
|
* per-proto parts (hence not IP_NAT_RANGE_PROTO_SPECIFIED).
|
|
* Use reply in case it's already been mangled (eg local packet).
|
|
*/
|
|
union nf_inet_addr ip =
|
|
(manip == NF_NAT_MANIP_SRC ?
|
|
ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3 :
|
|
ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3);
|
|
struct nf_nat_range2 range = {
|
|
.flags = NF_NAT_RANGE_MAP_IPS,
|
|
.min_addr = ip,
|
|
.max_addr = ip,
|
|
};
|
|
return nf_nat_setup_info(ct, &range, manip);
|
|
}
|
|
|
|
unsigned int
|
|
nf_nat_alloc_null_binding(struct nf_conn *ct, unsigned int hooknum)
|
|
{
|
|
return __nf_nat_alloc_null_binding(ct, HOOK2MANIP(hooknum));
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_nat_alloc_null_binding);
|
|
|
|
/* Do packet manipulations according to nf_nat_setup_info. */
|
|
unsigned int nf_nat_packet(struct nf_conn *ct,
|
|
enum ip_conntrack_info ctinfo,
|
|
unsigned int hooknum,
|
|
struct sk_buff *skb)
|
|
{
|
|
enum nf_nat_manip_type mtype = HOOK2MANIP(hooknum);
|
|
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
|
|
unsigned int verdict = NF_ACCEPT;
|
|
unsigned long statusbit;
|
|
|
|
if (mtype == NF_NAT_MANIP_SRC)
|
|
statusbit = IPS_SRC_NAT;
|
|
else
|
|
statusbit = IPS_DST_NAT;
|
|
|
|
/* Invert if this is reply dir. */
|
|
if (dir == IP_CT_DIR_REPLY)
|
|
statusbit ^= IPS_NAT_MASK;
|
|
|
|
/* Non-atomic: these bits don't change. */
|
|
if (ct->status & statusbit)
|
|
verdict = nf_nat_manip_pkt(skb, ct, mtype, dir);
|
|
|
|
return verdict;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_nat_packet);
|
|
|
|
unsigned int
|
|
nf_nat_inet_fn(void *priv, struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
struct nf_conn *ct;
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn_nat *nat;
|
|
/* maniptype == SRC for postrouting. */
|
|
enum nf_nat_manip_type maniptype = HOOK2MANIP(state->hook);
|
|
|
|
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;
|
|
|
|
nat = nfct_nat(ct);
|
|
|
|
switch (ctinfo) {
|
|
case IP_CT_RELATED:
|
|
case IP_CT_RELATED_REPLY:
|
|
/* Only ICMPs can be IP_CT_IS_REPLY. Fallthrough */
|
|
case IP_CT_NEW:
|
|
/* Seen it before? This can happen for loopback, retrans,
|
|
* or local packets.
|
|
*/
|
|
if (!nf_nat_initialized(ct, maniptype)) {
|
|
struct nf_nat_lookup_hook_priv *lpriv = priv;
|
|
struct nf_hook_entries *e = rcu_dereference(lpriv->entries);
|
|
unsigned int ret;
|
|
int i;
|
|
|
|
if (!e)
|
|
goto null_bind;
|
|
|
|
for (i = 0; i < e->num_hook_entries; i++) {
|
|
ret = e->hooks[i].hook(e->hooks[i].priv, skb,
|
|
state);
|
|
if (ret != NF_ACCEPT)
|
|
return ret;
|
|
if (nf_nat_initialized(ct, maniptype))
|
|
goto do_nat;
|
|
}
|
|
null_bind:
|
|
ret = nf_nat_alloc_null_binding(ct, state->hook);
|
|
if (ret != NF_ACCEPT)
|
|
return ret;
|
|
} else {
|
|
pr_debug("Already setup manip %s for ct %p (status bits 0x%lx)\n",
|
|
maniptype == NF_NAT_MANIP_SRC ? "SRC" : "DST",
|
|
ct, ct->status);
|
|
if (nf_nat_oif_changed(state->hook, ctinfo, nat,
|
|
state->out))
|
|
goto oif_changed;
|
|
}
|
|
break;
|
|
default:
|
|
/* ESTABLISHED */
|
|
WARN_ON(ctinfo != IP_CT_ESTABLISHED &&
|
|
ctinfo != IP_CT_ESTABLISHED_REPLY);
|
|
if (nf_nat_oif_changed(state->hook, ctinfo, nat, state->out))
|
|
goto oif_changed;
|
|
}
|
|
do_nat:
|
|
return nf_nat_packet(ct, ctinfo, state->hook, skb);
|
|
|
|
oif_changed:
|
|
nf_ct_kill_acct(ct, ctinfo, skb);
|
|
return NF_DROP;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_nat_inet_fn);
|
|
|
|
struct nf_nat_proto_clean {
|
|
u8 l3proto;
|
|
u8 l4proto;
|
|
};
|
|
|
|
/* kill conntracks with affected NAT section */
|
|
static int nf_nat_proto_remove(struct nf_conn *i, void *data)
|
|
{
|
|
const struct nf_nat_proto_clean *clean = data;
|
|
|
|
if ((clean->l3proto && nf_ct_l3num(i) != clean->l3proto) ||
|
|
(clean->l4proto && nf_ct_protonum(i) != clean->l4proto))
|
|
return 0;
|
|
|
|
return i->status & IPS_NAT_MASK ? 1 : 0;
|
|
}
|
|
|
|
static void __nf_nat_cleanup_conntrack(struct nf_conn *ct)
|
|
{
|
|
unsigned int h;
|
|
|
|
h = hash_by_src(nf_ct_net(ct), &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
|
|
spin_lock_bh(&nf_nat_locks[h % CONNTRACK_LOCKS]);
|
|
hlist_del_rcu(&ct->nat_bysource);
|
|
spin_unlock_bh(&nf_nat_locks[h % CONNTRACK_LOCKS]);
|
|
}
|
|
|
|
static int nf_nat_proto_clean(struct nf_conn *ct, void *data)
|
|
{
|
|
if (nf_nat_proto_remove(ct, data))
|
|
return 1;
|
|
|
|
/* This module is being removed and conntrack has nat null binding.
|
|
* Remove it from bysource hash, as the table will be freed soon.
|
|
*
|
|
* Else, when the conntrack is destoyed, nf_nat_cleanup_conntrack()
|
|
* will delete entry from already-freed table.
|
|
*/
|
|
if (test_and_clear_bit(IPS_SRC_NAT_DONE_BIT, &ct->status))
|
|
__nf_nat_cleanup_conntrack(ct);
|
|
|
|
/* don't delete conntrack. Although that would make things a lot
|
|
* simpler, we'd end up flushing all conntracks on nat rmmod.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
/* No one using conntrack by the time this called. */
|
|
static void nf_nat_cleanup_conntrack(struct nf_conn *ct)
|
|
{
|
|
if (ct->status & IPS_SRC_NAT_DONE)
|
|
__nf_nat_cleanup_conntrack(ct);
|
|
}
|
|
|
|
static struct nf_ct_ext_type nat_extend __read_mostly = {
|
|
.len = sizeof(struct nf_conn_nat),
|
|
.align = __alignof__(struct nf_conn_nat),
|
|
.destroy = nf_nat_cleanup_conntrack,
|
|
.id = NF_CT_EXT_NAT,
|
|
};
|
|
|
|
#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
|
|
|
|
#include <linux/netfilter/nfnetlink.h>
|
|
#include <linux/netfilter/nfnetlink_conntrack.h>
|
|
|
|
static const struct nla_policy protonat_nla_policy[CTA_PROTONAT_MAX+1] = {
|
|
[CTA_PROTONAT_PORT_MIN] = { .type = NLA_U16 },
|
|
[CTA_PROTONAT_PORT_MAX] = { .type = NLA_U16 },
|
|
};
|
|
|
|
static int nf_nat_l4proto_nlattr_to_range(struct nlattr *tb[],
|
|
struct nf_nat_range2 *range)
|
|
{
|
|
if (tb[CTA_PROTONAT_PORT_MIN]) {
|
|
range->min_proto.all = nla_get_be16(tb[CTA_PROTONAT_PORT_MIN]);
|
|
range->max_proto.all = range->min_proto.all;
|
|
range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
|
|
}
|
|
if (tb[CTA_PROTONAT_PORT_MAX]) {
|
|
range->max_proto.all = nla_get_be16(tb[CTA_PROTONAT_PORT_MAX]);
|
|
range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int nfnetlink_parse_nat_proto(struct nlattr *attr,
|
|
const struct nf_conn *ct,
|
|
struct nf_nat_range2 *range)
|
|
{
|
|
struct nlattr *tb[CTA_PROTONAT_MAX+1];
|
|
int err;
|
|
|
|
err = nla_parse_nested_deprecated(tb, CTA_PROTONAT_MAX, attr,
|
|
protonat_nla_policy, NULL);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
return nf_nat_l4proto_nlattr_to_range(tb, range);
|
|
}
|
|
|
|
static const struct nla_policy nat_nla_policy[CTA_NAT_MAX+1] = {
|
|
[CTA_NAT_V4_MINIP] = { .type = NLA_U32 },
|
|
[CTA_NAT_V4_MAXIP] = { .type = NLA_U32 },
|
|
[CTA_NAT_V6_MINIP] = { .len = sizeof(struct in6_addr) },
|
|
[CTA_NAT_V6_MAXIP] = { .len = sizeof(struct in6_addr) },
|
|
[CTA_NAT_PROTO] = { .type = NLA_NESTED },
|
|
};
|
|
|
|
static int nf_nat_ipv4_nlattr_to_range(struct nlattr *tb[],
|
|
struct nf_nat_range2 *range)
|
|
{
|
|
if (tb[CTA_NAT_V4_MINIP]) {
|
|
range->min_addr.ip = nla_get_be32(tb[CTA_NAT_V4_MINIP]);
|
|
range->flags |= NF_NAT_RANGE_MAP_IPS;
|
|
}
|
|
|
|
if (tb[CTA_NAT_V4_MAXIP])
|
|
range->max_addr.ip = nla_get_be32(tb[CTA_NAT_V4_MAXIP]);
|
|
else
|
|
range->max_addr.ip = range->min_addr.ip;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int nf_nat_ipv6_nlattr_to_range(struct nlattr *tb[],
|
|
struct nf_nat_range2 *range)
|
|
{
|
|
if (tb[CTA_NAT_V6_MINIP]) {
|
|
nla_memcpy(&range->min_addr.ip6, tb[CTA_NAT_V6_MINIP],
|
|
sizeof(struct in6_addr));
|
|
range->flags |= NF_NAT_RANGE_MAP_IPS;
|
|
}
|
|
|
|
if (tb[CTA_NAT_V6_MAXIP])
|
|
nla_memcpy(&range->max_addr.ip6, tb[CTA_NAT_V6_MAXIP],
|
|
sizeof(struct in6_addr));
|
|
else
|
|
range->max_addr = range->min_addr;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
nfnetlink_parse_nat(const struct nlattr *nat,
|
|
const struct nf_conn *ct, struct nf_nat_range2 *range)
|
|
{
|
|
struct nlattr *tb[CTA_NAT_MAX+1];
|
|
int err;
|
|
|
|
memset(range, 0, sizeof(*range));
|
|
|
|
err = nla_parse_nested_deprecated(tb, CTA_NAT_MAX, nat,
|
|
nat_nla_policy, NULL);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
switch (nf_ct_l3num(ct)) {
|
|
case NFPROTO_IPV4:
|
|
err = nf_nat_ipv4_nlattr_to_range(tb, range);
|
|
break;
|
|
case NFPROTO_IPV6:
|
|
err = nf_nat_ipv6_nlattr_to_range(tb, range);
|
|
break;
|
|
default:
|
|
err = -EPROTONOSUPPORT;
|
|
break;
|
|
}
|
|
|
|
if (err)
|
|
return err;
|
|
|
|
if (!tb[CTA_NAT_PROTO])
|
|
return 0;
|
|
|
|
return nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO], ct, range);
|
|
}
|
|
|
|
/* This function is called under rcu_read_lock() */
|
|
static int
|
|
nfnetlink_parse_nat_setup(struct nf_conn *ct,
|
|
enum nf_nat_manip_type manip,
|
|
const struct nlattr *attr)
|
|
{
|
|
struct nf_nat_range2 range;
|
|
int err;
|
|
|
|
/* Should not happen, restricted to creating new conntracks
|
|
* via ctnetlink.
|
|
*/
|
|
if (WARN_ON_ONCE(nf_nat_initialized(ct, manip)))
|
|
return -EEXIST;
|
|
|
|
/* No NAT information has been passed, allocate the null-binding */
|
|
if (attr == NULL)
|
|
return __nf_nat_alloc_null_binding(ct, manip) == NF_DROP ? -ENOMEM : 0;
|
|
|
|
err = nfnetlink_parse_nat(attr, ct, &range);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
return nf_nat_setup_info(ct, &range, manip) == NF_DROP ? -ENOMEM : 0;
|
|
}
|
|
#else
|
|
static int
|
|
nfnetlink_parse_nat_setup(struct nf_conn *ct,
|
|
enum nf_nat_manip_type manip,
|
|
const struct nlattr *attr)
|
|
{
|
|
return -EOPNOTSUPP;
|
|
}
|
|
#endif
|
|
|
|
static struct nf_ct_helper_expectfn follow_master_nat = {
|
|
.name = "nat-follow-master",
|
|
.expectfn = nf_nat_follow_master,
|
|
};
|
|
|
|
int nf_nat_register_fn(struct net *net, u8 pf, const struct nf_hook_ops *ops,
|
|
const struct nf_hook_ops *orig_nat_ops, unsigned int ops_count)
|
|
{
|
|
struct nat_net *nat_net = net_generic(net, nat_net_id);
|
|
struct nf_nat_hooks_net *nat_proto_net;
|
|
struct nf_nat_lookup_hook_priv *priv;
|
|
unsigned int hooknum = ops->hooknum;
|
|
struct nf_hook_ops *nat_ops;
|
|
int i, ret;
|
|
|
|
if (WARN_ON_ONCE(pf >= ARRAY_SIZE(nat_net->nat_proto_net)))
|
|
return -EINVAL;
|
|
|
|
nat_proto_net = &nat_net->nat_proto_net[pf];
|
|
|
|
for (i = 0; i < ops_count; i++) {
|
|
if (orig_nat_ops[i].hooknum == hooknum) {
|
|
hooknum = i;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (WARN_ON_ONCE(i == ops_count))
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&nf_nat_proto_mutex);
|
|
if (!nat_proto_net->nat_hook_ops) {
|
|
WARN_ON(nat_proto_net->users != 0);
|
|
|
|
nat_ops = kmemdup(orig_nat_ops, sizeof(*orig_nat_ops) * ops_count, GFP_KERNEL);
|
|
if (!nat_ops) {
|
|
mutex_unlock(&nf_nat_proto_mutex);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
for (i = 0; i < ops_count; i++) {
|
|
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
|
|
if (priv) {
|
|
nat_ops[i].priv = priv;
|
|
continue;
|
|
}
|
|
mutex_unlock(&nf_nat_proto_mutex);
|
|
while (i)
|
|
kfree(nat_ops[--i].priv);
|
|
kfree(nat_ops);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
ret = nf_register_net_hooks(net, nat_ops, ops_count);
|
|
if (ret < 0) {
|
|
mutex_unlock(&nf_nat_proto_mutex);
|
|
for (i = 0; i < ops_count; i++)
|
|
kfree(nat_ops[i].priv);
|
|
kfree(nat_ops);
|
|
return ret;
|
|
}
|
|
|
|
nat_proto_net->nat_hook_ops = nat_ops;
|
|
}
|
|
|
|
nat_ops = nat_proto_net->nat_hook_ops;
|
|
priv = nat_ops[hooknum].priv;
|
|
if (WARN_ON_ONCE(!priv)) {
|
|
mutex_unlock(&nf_nat_proto_mutex);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
ret = nf_hook_entries_insert_raw(&priv->entries, ops);
|
|
if (ret == 0)
|
|
nat_proto_net->users++;
|
|
|
|
mutex_unlock(&nf_nat_proto_mutex);
|
|
return ret;
|
|
}
|
|
|
|
void nf_nat_unregister_fn(struct net *net, u8 pf, const struct nf_hook_ops *ops,
|
|
unsigned int ops_count)
|
|
{
|
|
struct nat_net *nat_net = net_generic(net, nat_net_id);
|
|
struct nf_nat_hooks_net *nat_proto_net;
|
|
struct nf_nat_lookup_hook_priv *priv;
|
|
struct nf_hook_ops *nat_ops;
|
|
int hooknum = ops->hooknum;
|
|
int i;
|
|
|
|
if (pf >= ARRAY_SIZE(nat_net->nat_proto_net))
|
|
return;
|
|
|
|
nat_proto_net = &nat_net->nat_proto_net[pf];
|
|
|
|
mutex_lock(&nf_nat_proto_mutex);
|
|
if (WARN_ON(nat_proto_net->users == 0))
|
|
goto unlock;
|
|
|
|
nat_proto_net->users--;
|
|
|
|
nat_ops = nat_proto_net->nat_hook_ops;
|
|
for (i = 0; i < ops_count; i++) {
|
|
if (nat_ops[i].hooknum == hooknum) {
|
|
hooknum = i;
|
|
break;
|
|
}
|
|
}
|
|
if (WARN_ON_ONCE(i == ops_count))
|
|
goto unlock;
|
|
priv = nat_ops[hooknum].priv;
|
|
nf_hook_entries_delete_raw(&priv->entries, ops);
|
|
|
|
if (nat_proto_net->users == 0) {
|
|
nf_unregister_net_hooks(net, nat_ops, ops_count);
|
|
|
|
for (i = 0; i < ops_count; i++) {
|
|
priv = nat_ops[i].priv;
|
|
kfree_rcu(priv, rcu_head);
|
|
}
|
|
|
|
nat_proto_net->nat_hook_ops = NULL;
|
|
kfree(nat_ops);
|
|
}
|
|
unlock:
|
|
mutex_unlock(&nf_nat_proto_mutex);
|
|
}
|
|
|
|
static struct pernet_operations nat_net_ops = {
|
|
.id = &nat_net_id,
|
|
.size = sizeof(struct nat_net),
|
|
};
|
|
|
|
static struct nf_nat_hook nat_hook = {
|
|
.parse_nat_setup = nfnetlink_parse_nat_setup,
|
|
#ifdef CONFIG_XFRM
|
|
.decode_session = __nf_nat_decode_session,
|
|
#endif
|
|
.manip_pkt = nf_nat_manip_pkt,
|
|
};
|
|
|
|
static int __init nf_nat_init(void)
|
|
{
|
|
int ret, i;
|
|
|
|
/* Leave them the same for the moment. */
|
|
nf_nat_htable_size = nf_conntrack_htable_size;
|
|
if (nf_nat_htable_size < CONNTRACK_LOCKS)
|
|
nf_nat_htable_size = CONNTRACK_LOCKS;
|
|
|
|
nf_nat_bysource = nf_ct_alloc_hashtable(&nf_nat_htable_size, 0);
|
|
if (!nf_nat_bysource)
|
|
return -ENOMEM;
|
|
|
|
ret = nf_ct_extend_register(&nat_extend);
|
|
if (ret < 0) {
|
|
kvfree(nf_nat_bysource);
|
|
pr_err("Unable to register extension\n");
|
|
return ret;
|
|
}
|
|
|
|
for (i = 0; i < CONNTRACK_LOCKS; i++)
|
|
spin_lock_init(&nf_nat_locks[i]);
|
|
|
|
ret = register_pernet_subsys(&nat_net_ops);
|
|
if (ret < 0) {
|
|
nf_ct_extend_unregister(&nat_extend);
|
|
return ret;
|
|
}
|
|
|
|
nf_ct_helper_expectfn_register(&follow_master_nat);
|
|
|
|
WARN_ON(nf_nat_hook != NULL);
|
|
RCU_INIT_POINTER(nf_nat_hook, &nat_hook);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit nf_nat_cleanup(void)
|
|
{
|
|
struct nf_nat_proto_clean clean = {};
|
|
|
|
nf_ct_iterate_destroy(nf_nat_proto_clean, &clean);
|
|
|
|
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);
|
|
}
|
|
|
|
MODULE_LICENSE("GPL");
|
|
|
|
module_init(nf_nat_init);
|
|
module_exit(nf_nat_cleanup);
|