![Sasha Levin](/assets/img/avatar_default.png)
When we need to lock all buckets in the connection hashtable we'd attempt to lock 1024 spinlocks, which is way more preemption levels than supported by the kernel. Furthermore, this behavior was hidden by checking if lockdep is enabled, and if it was - use only 8 buckets(!). Fix this by using a global lock and synchronize all buckets on it when we need to lock them all. This is pretty heavyweight, but is only done when we need to resize the hashtable, and that doesn't happen often enough (or at all). Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
1861 lines
49 KiB
C
1861 lines
49 KiB
C
/* Connection state tracking for netfilter. This is separated from,
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but required by, the NAT layer; it can also be used by an iptables
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extension. */
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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) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org>
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* (C) 2005-2012 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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#include <linux/types.h>
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#include <linux/netfilter.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/skbuff.h>
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#include <linux/proc_fs.h>
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#include <linux/vmalloc.h>
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#include <linux/stddef.h>
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#include <linux/slab.h>
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#include <linux/random.h>
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#include <linux/jhash.h>
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#include <linux/err.h>
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#include <linux/percpu.h>
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#include <linux/moduleparam.h>
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#include <linux/notifier.h>
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#include <linux/kernel.h>
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#include <linux/netdevice.h>
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#include <linux/socket.h>
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#include <linux/mm.h>
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#include <linux/nsproxy.h>
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#include <linux/rculist_nulls.h>
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_conntrack_l3proto.h>
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#include <net/netfilter/nf_conntrack_l4proto.h>
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#include <net/netfilter/nf_conntrack_expect.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_core.h>
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#include <net/netfilter/nf_conntrack_extend.h>
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#include <net/netfilter/nf_conntrack_acct.h>
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#include <net/netfilter/nf_conntrack_ecache.h>
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#include <net/netfilter/nf_conntrack_zones.h>
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#include <net/netfilter/nf_conntrack_timestamp.h>
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#include <net/netfilter/nf_conntrack_timeout.h>
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#include <net/netfilter/nf_conntrack_labels.h>
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#include <net/netfilter/nf_conntrack_synproxy.h>
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#include <net/netfilter/nf_nat.h>
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#include <net/netfilter/nf_nat_core.h>
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#include <net/netfilter/nf_nat_helper.h>
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#define NF_CONNTRACK_VERSION "0.5.0"
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int (*nfnetlink_parse_nat_setup_hook)(struct nf_conn *ct,
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enum nf_nat_manip_type manip,
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const struct nlattr *attr) __read_mostly;
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EXPORT_SYMBOL_GPL(nfnetlink_parse_nat_setup_hook);
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__cacheline_aligned_in_smp spinlock_t nf_conntrack_locks[CONNTRACK_LOCKS];
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EXPORT_SYMBOL_GPL(nf_conntrack_locks);
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__cacheline_aligned_in_smp DEFINE_SPINLOCK(nf_conntrack_expect_lock);
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EXPORT_SYMBOL_GPL(nf_conntrack_expect_lock);
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static __read_mostly spinlock_t nf_conntrack_locks_all_lock;
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static __read_mostly bool nf_conntrack_locks_all;
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void nf_conntrack_lock(spinlock_t *lock) __acquires(lock)
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{
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spin_lock(lock);
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while (unlikely(nf_conntrack_locks_all)) {
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spin_unlock(lock);
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spin_lock(&nf_conntrack_locks_all_lock);
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spin_unlock(&nf_conntrack_locks_all_lock);
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spin_lock(lock);
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}
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}
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EXPORT_SYMBOL_GPL(nf_conntrack_lock);
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static void nf_conntrack_double_unlock(unsigned int h1, unsigned int h2)
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{
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h1 %= CONNTRACK_LOCKS;
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h2 %= CONNTRACK_LOCKS;
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spin_unlock(&nf_conntrack_locks[h1]);
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if (h1 != h2)
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spin_unlock(&nf_conntrack_locks[h2]);
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}
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/* return true if we need to recompute hashes (in case hash table was resized) */
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static bool nf_conntrack_double_lock(struct net *net, unsigned int h1,
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unsigned int h2, unsigned int sequence)
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{
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h1 %= CONNTRACK_LOCKS;
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h2 %= CONNTRACK_LOCKS;
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if (h1 <= h2) {
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nf_conntrack_lock(&nf_conntrack_locks[h1]);
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if (h1 != h2)
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spin_lock_nested(&nf_conntrack_locks[h2],
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SINGLE_DEPTH_NESTING);
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} else {
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nf_conntrack_lock(&nf_conntrack_locks[h2]);
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spin_lock_nested(&nf_conntrack_locks[h1],
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SINGLE_DEPTH_NESTING);
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}
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if (read_seqcount_retry(&net->ct.generation, sequence)) {
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nf_conntrack_double_unlock(h1, h2);
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return true;
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}
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return false;
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}
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static void nf_conntrack_all_lock(void)
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{
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int i;
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spin_lock(&nf_conntrack_locks_all_lock);
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nf_conntrack_locks_all = true;
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for (i = 0; i < CONNTRACK_LOCKS; i++) {
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spin_lock(&nf_conntrack_locks[i]);
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spin_unlock(&nf_conntrack_locks[i]);
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}
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}
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static void nf_conntrack_all_unlock(void)
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{
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nf_conntrack_locks_all = false;
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spin_unlock(&nf_conntrack_locks_all_lock);
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}
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unsigned int nf_conntrack_htable_size __read_mostly;
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EXPORT_SYMBOL_GPL(nf_conntrack_htable_size);
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unsigned int nf_conntrack_max __read_mostly;
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EXPORT_SYMBOL_GPL(nf_conntrack_max);
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DEFINE_PER_CPU(struct nf_conn, nf_conntrack_untracked);
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EXPORT_PER_CPU_SYMBOL(nf_conntrack_untracked);
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unsigned int nf_conntrack_hash_rnd __read_mostly;
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EXPORT_SYMBOL_GPL(nf_conntrack_hash_rnd);
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static u32 hash_conntrack_raw(const struct nf_conntrack_tuple *tuple)
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{
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unsigned int n;
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/* The direction must be ignored, so we hash everything up to the
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* destination ports (which is a multiple of 4) and treat the last
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* three bytes manually.
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*/
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n = (sizeof(tuple->src) + sizeof(tuple->dst.u3)) / sizeof(u32);
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return jhash2((u32 *)tuple, n, nf_conntrack_hash_rnd ^
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(((__force __u16)tuple->dst.u.all << 16) |
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tuple->dst.protonum));
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}
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static u32 __hash_bucket(u32 hash, unsigned int size)
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{
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return reciprocal_scale(hash, size);
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}
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static u32 hash_bucket(u32 hash, const struct net *net)
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{
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return __hash_bucket(hash, net->ct.htable_size);
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}
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static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple,
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unsigned int size)
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{
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return __hash_bucket(hash_conntrack_raw(tuple), size);
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}
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static inline u_int32_t hash_conntrack(const struct net *net,
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const struct nf_conntrack_tuple *tuple)
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{
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return __hash_conntrack(tuple, net->ct.htable_size);
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}
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bool
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nf_ct_get_tuple(const struct sk_buff *skb,
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unsigned int nhoff,
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unsigned int dataoff,
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u_int16_t l3num,
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u_int8_t protonum,
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struct net *net,
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struct nf_conntrack_tuple *tuple,
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const struct nf_conntrack_l3proto *l3proto,
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const struct nf_conntrack_l4proto *l4proto)
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{
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memset(tuple, 0, sizeof(*tuple));
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tuple->src.l3num = l3num;
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if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0)
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return false;
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tuple->dst.protonum = protonum;
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tuple->dst.dir = IP_CT_DIR_ORIGINAL;
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return l4proto->pkt_to_tuple(skb, dataoff, net, tuple);
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}
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EXPORT_SYMBOL_GPL(nf_ct_get_tuple);
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bool nf_ct_get_tuplepr(const struct sk_buff *skb, unsigned int nhoff,
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u_int16_t l3num,
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struct net *net, struct nf_conntrack_tuple *tuple)
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{
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struct nf_conntrack_l3proto *l3proto;
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struct nf_conntrack_l4proto *l4proto;
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unsigned int protoff;
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u_int8_t protonum;
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int ret;
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rcu_read_lock();
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l3proto = __nf_ct_l3proto_find(l3num);
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ret = l3proto->get_l4proto(skb, nhoff, &protoff, &protonum);
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if (ret != NF_ACCEPT) {
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rcu_read_unlock();
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return false;
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}
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l4proto = __nf_ct_l4proto_find(l3num, protonum);
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ret = nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, net, tuple,
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l3proto, l4proto);
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rcu_read_unlock();
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return ret;
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}
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EXPORT_SYMBOL_GPL(nf_ct_get_tuplepr);
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bool
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nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse,
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const struct nf_conntrack_tuple *orig,
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const struct nf_conntrack_l3proto *l3proto,
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const struct nf_conntrack_l4proto *l4proto)
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{
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memset(inverse, 0, sizeof(*inverse));
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inverse->src.l3num = orig->src.l3num;
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if (l3proto->invert_tuple(inverse, orig) == 0)
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return false;
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inverse->dst.dir = !orig->dst.dir;
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inverse->dst.protonum = orig->dst.protonum;
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return l4proto->invert_tuple(inverse, orig);
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}
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EXPORT_SYMBOL_GPL(nf_ct_invert_tuple);
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static void
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clean_from_lists(struct nf_conn *ct)
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{
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pr_debug("clean_from_lists(%p)\n", ct);
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hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode);
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hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode);
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/* Destroy all pending expectations */
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nf_ct_remove_expectations(ct);
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}
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/* must be called with local_bh_disable */
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static void nf_ct_add_to_dying_list(struct nf_conn *ct)
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{
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struct ct_pcpu *pcpu;
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/* add this conntrack to the (per cpu) dying list */
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ct->cpu = smp_processor_id();
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pcpu = per_cpu_ptr(nf_ct_net(ct)->ct.pcpu_lists, ct->cpu);
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spin_lock(&pcpu->lock);
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hlist_nulls_add_head(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode,
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&pcpu->dying);
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spin_unlock(&pcpu->lock);
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}
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/* must be called with local_bh_disable */
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static void nf_ct_add_to_unconfirmed_list(struct nf_conn *ct)
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{
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struct ct_pcpu *pcpu;
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/* add this conntrack to the (per cpu) unconfirmed list */
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ct->cpu = smp_processor_id();
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pcpu = per_cpu_ptr(nf_ct_net(ct)->ct.pcpu_lists, ct->cpu);
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spin_lock(&pcpu->lock);
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hlist_nulls_add_head(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode,
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&pcpu->unconfirmed);
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spin_unlock(&pcpu->lock);
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}
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/* must be called with local_bh_disable */
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static void nf_ct_del_from_dying_or_unconfirmed_list(struct nf_conn *ct)
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{
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struct ct_pcpu *pcpu;
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/* We overload first tuple to link into unconfirmed or dying list.*/
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pcpu = per_cpu_ptr(nf_ct_net(ct)->ct.pcpu_lists, ct->cpu);
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spin_lock(&pcpu->lock);
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BUG_ON(hlist_nulls_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode));
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hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode);
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spin_unlock(&pcpu->lock);
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}
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/* Released via destroy_conntrack() */
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struct nf_conn *nf_ct_tmpl_alloc(struct net *net,
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const struct nf_conntrack_zone *zone,
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gfp_t flags)
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{
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struct nf_conn *tmpl;
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tmpl = kzalloc(sizeof(*tmpl), flags);
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if (tmpl == NULL)
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return NULL;
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tmpl->status = IPS_TEMPLATE;
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write_pnet(&tmpl->ct_net, net);
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if (nf_ct_zone_add(tmpl, flags, zone) < 0)
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goto out_free;
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atomic_set(&tmpl->ct_general.use, 0);
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return tmpl;
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out_free:
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kfree(tmpl);
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return NULL;
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}
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EXPORT_SYMBOL_GPL(nf_ct_tmpl_alloc);
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void nf_ct_tmpl_free(struct nf_conn *tmpl)
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{
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nf_ct_ext_destroy(tmpl);
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nf_ct_ext_free(tmpl);
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kfree(tmpl);
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}
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EXPORT_SYMBOL_GPL(nf_ct_tmpl_free);
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static void
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destroy_conntrack(struct nf_conntrack *nfct)
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{
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struct nf_conn *ct = (struct nf_conn *)nfct;
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struct net *net = nf_ct_net(ct);
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struct nf_conntrack_l4proto *l4proto;
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pr_debug("destroy_conntrack(%p)\n", ct);
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NF_CT_ASSERT(atomic_read(&nfct->use) == 0);
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NF_CT_ASSERT(!timer_pending(&ct->timeout));
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if (unlikely(nf_ct_is_template(ct))) {
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nf_ct_tmpl_free(ct);
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return;
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}
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rcu_read_lock();
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l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
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if (l4proto && l4proto->destroy)
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l4proto->destroy(ct);
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rcu_read_unlock();
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local_bh_disable();
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/* Expectations will have been removed in clean_from_lists,
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* except TFTP can create an expectation on the first packet,
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* before connection is in the list, so we need to clean here,
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* too.
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*/
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nf_ct_remove_expectations(ct);
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nf_ct_del_from_dying_or_unconfirmed_list(ct);
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NF_CT_STAT_INC(net, delete);
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local_bh_enable();
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if (ct->master)
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nf_ct_put(ct->master);
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pr_debug("destroy_conntrack: returning ct=%p to slab\n", ct);
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nf_conntrack_free(ct);
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}
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static void nf_ct_delete_from_lists(struct nf_conn *ct)
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{
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struct net *net = nf_ct_net(ct);
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unsigned int hash, reply_hash;
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unsigned int sequence;
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nf_ct_helper_destroy(ct);
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local_bh_disable();
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do {
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sequence = read_seqcount_begin(&net->ct.generation);
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hash = hash_conntrack(net,
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&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
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reply_hash = hash_conntrack(net,
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&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
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} while (nf_conntrack_double_lock(net, hash, reply_hash, sequence));
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clean_from_lists(ct);
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nf_conntrack_double_unlock(hash, reply_hash);
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nf_ct_add_to_dying_list(ct);
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NF_CT_STAT_INC(net, delete_list);
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local_bh_enable();
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}
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bool nf_ct_delete(struct nf_conn *ct, u32 portid, int report)
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{
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struct nf_conn_tstamp *tstamp;
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tstamp = nf_conn_tstamp_find(ct);
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if (tstamp && tstamp->stop == 0)
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tstamp->stop = ktime_get_real_ns();
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if (nf_ct_is_dying(ct))
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goto delete;
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if (nf_conntrack_event_report(IPCT_DESTROY, ct,
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portid, report) < 0) {
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/* destroy event was not delivered */
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nf_ct_delete_from_lists(ct);
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nf_conntrack_ecache_delayed_work(nf_ct_net(ct));
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return false;
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}
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nf_conntrack_ecache_work(nf_ct_net(ct));
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set_bit(IPS_DYING_BIT, &ct->status);
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delete:
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nf_ct_delete_from_lists(ct);
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nf_ct_put(ct);
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return true;
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}
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EXPORT_SYMBOL_GPL(nf_ct_delete);
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static void death_by_timeout(unsigned long ul_conntrack)
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{
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nf_ct_delete((struct nf_conn *)ul_conntrack, 0, 0);
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}
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static inline bool
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nf_ct_key_equal(struct nf_conntrack_tuple_hash *h,
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const struct nf_conntrack_tuple *tuple,
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const struct nf_conntrack_zone *zone)
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{
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struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
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/* A conntrack can be recreated with the equal tuple,
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* so we need to check that the conntrack is confirmed
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*/
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return nf_ct_tuple_equal(tuple, &h->tuple) &&
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nf_ct_zone_equal(ct, zone, NF_CT_DIRECTION(h)) &&
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nf_ct_is_confirmed(ct);
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}
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|
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/*
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* Warning :
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* - Caller must take a reference on returned object
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|
* and recheck nf_ct_tuple_equal(tuple, &h->tuple)
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*/
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static struct nf_conntrack_tuple_hash *
|
|
____nf_conntrack_find(struct net *net, const struct nf_conntrack_zone *zone,
|
|
const struct nf_conntrack_tuple *tuple, u32 hash)
|
|
{
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct hlist_nulls_node *n;
|
|
unsigned int bucket = hash_bucket(hash, net);
|
|
|
|
/* Disable BHs the entire time since we normally need to disable them
|
|
* at least once for the stats anyway.
|
|
*/
|
|
local_bh_disable();
|
|
begin:
|
|
hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[bucket], hnnode) {
|
|
if (nf_ct_key_equal(h, tuple, zone)) {
|
|
NF_CT_STAT_INC(net, found);
|
|
local_bh_enable();
|
|
return h;
|
|
}
|
|
NF_CT_STAT_INC(net, searched);
|
|
}
|
|
/*
|
|
* if the nulls value we got at the end of this lookup is
|
|
* not the expected one, we must restart lookup.
|
|
* We probably met an item that was moved to another chain.
|
|
*/
|
|
if (get_nulls_value(n) != bucket) {
|
|
NF_CT_STAT_INC(net, search_restart);
|
|
goto begin;
|
|
}
|
|
local_bh_enable();
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/* Find a connection corresponding to a tuple. */
|
|
static struct nf_conntrack_tuple_hash *
|
|
__nf_conntrack_find_get(struct net *net, const struct nf_conntrack_zone *zone,
|
|
const struct nf_conntrack_tuple *tuple, u32 hash)
|
|
{
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct;
|
|
|
|
rcu_read_lock();
|
|
begin:
|
|
h = ____nf_conntrack_find(net, zone, tuple, hash);
|
|
if (h) {
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
if (unlikely(nf_ct_is_dying(ct) ||
|
|
!atomic_inc_not_zero(&ct->ct_general.use)))
|
|
h = NULL;
|
|
else {
|
|
if (unlikely(!nf_ct_key_equal(h, tuple, zone))) {
|
|
nf_ct_put(ct);
|
|
goto begin;
|
|
}
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return h;
|
|
}
|
|
|
|
struct nf_conntrack_tuple_hash *
|
|
nf_conntrack_find_get(struct net *net, const struct nf_conntrack_zone *zone,
|
|
const struct nf_conntrack_tuple *tuple)
|
|
{
|
|
return __nf_conntrack_find_get(net, zone, tuple,
|
|
hash_conntrack_raw(tuple));
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_find_get);
|
|
|
|
static void __nf_conntrack_hash_insert(struct nf_conn *ct,
|
|
unsigned int hash,
|
|
unsigned int reply_hash)
|
|
{
|
|
struct net *net = nf_ct_net(ct);
|
|
|
|
hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode,
|
|
&net->ct.hash[hash]);
|
|
hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode,
|
|
&net->ct.hash[reply_hash]);
|
|
}
|
|
|
|
int
|
|
nf_conntrack_hash_check_insert(struct nf_conn *ct)
|
|
{
|
|
const struct nf_conntrack_zone *zone;
|
|
struct net *net = nf_ct_net(ct);
|
|
unsigned int hash, reply_hash;
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct hlist_nulls_node *n;
|
|
unsigned int sequence;
|
|
|
|
zone = nf_ct_zone(ct);
|
|
|
|
local_bh_disable();
|
|
do {
|
|
sequence = read_seqcount_begin(&net->ct.generation);
|
|
hash = hash_conntrack(net,
|
|
&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
|
|
reply_hash = hash_conntrack(net,
|
|
&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
|
|
} while (nf_conntrack_double_lock(net, hash, reply_hash, sequence));
|
|
|
|
/* See if there's one in the list already, including reverse */
|
|
hlist_nulls_for_each_entry(h, n, &net->ct.hash[hash], hnnode)
|
|
if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
|
|
&h->tuple) &&
|
|
nf_ct_zone_equal(nf_ct_tuplehash_to_ctrack(h), zone,
|
|
NF_CT_DIRECTION(h)))
|
|
goto out;
|
|
hlist_nulls_for_each_entry(h, n, &net->ct.hash[reply_hash], hnnode)
|
|
if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple,
|
|
&h->tuple) &&
|
|
nf_ct_zone_equal(nf_ct_tuplehash_to_ctrack(h), zone,
|
|
NF_CT_DIRECTION(h)))
|
|
goto out;
|
|
|
|
add_timer(&ct->timeout);
|
|
smp_wmb();
|
|
/* The caller holds a reference to this object */
|
|
atomic_set(&ct->ct_general.use, 2);
|
|
__nf_conntrack_hash_insert(ct, hash, reply_hash);
|
|
nf_conntrack_double_unlock(hash, reply_hash);
|
|
NF_CT_STAT_INC(net, insert);
|
|
local_bh_enable();
|
|
return 0;
|
|
|
|
out:
|
|
nf_conntrack_double_unlock(hash, reply_hash);
|
|
NF_CT_STAT_INC(net, insert_failed);
|
|
local_bh_enable();
|
|
return -EEXIST;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_hash_check_insert);
|
|
|
|
/* Confirm a connection given skb; places it in hash table */
|
|
int
|
|
__nf_conntrack_confirm(struct sk_buff *skb)
|
|
{
|
|
const struct nf_conntrack_zone *zone;
|
|
unsigned int hash, reply_hash;
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct;
|
|
struct nf_conn_help *help;
|
|
struct nf_conn_tstamp *tstamp;
|
|
struct hlist_nulls_node *n;
|
|
enum ip_conntrack_info ctinfo;
|
|
struct net *net;
|
|
unsigned int sequence;
|
|
|
|
ct = nf_ct_get(skb, &ctinfo);
|
|
net = nf_ct_net(ct);
|
|
|
|
/* ipt_REJECT uses nf_conntrack_attach to attach related
|
|
ICMP/TCP RST packets in other direction. Actual packet
|
|
which created connection will be IP_CT_NEW or for an
|
|
expected connection, IP_CT_RELATED. */
|
|
if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL)
|
|
return NF_ACCEPT;
|
|
|
|
zone = nf_ct_zone(ct);
|
|
local_bh_disable();
|
|
|
|
do {
|
|
sequence = read_seqcount_begin(&net->ct.generation);
|
|
/* reuse the hash saved before */
|
|
hash = *(unsigned long *)&ct->tuplehash[IP_CT_DIR_REPLY].hnnode.pprev;
|
|
hash = hash_bucket(hash, net);
|
|
reply_hash = hash_conntrack(net,
|
|
&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
|
|
|
|
} while (nf_conntrack_double_lock(net, hash, reply_hash, sequence));
|
|
|
|
/* We're not in hash table, and we refuse to set up related
|
|
* connections for unconfirmed conns. But packet copies and
|
|
* REJECT will give spurious warnings here.
|
|
*/
|
|
/* NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 1); */
|
|
|
|
/* No external references means no one else could have
|
|
* confirmed us.
|
|
*/
|
|
NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
|
|
pr_debug("Confirming conntrack %p\n", ct);
|
|
/* We have to check the DYING flag after unlink to prevent
|
|
* a race against nf_ct_get_next_corpse() possibly called from
|
|
* user context, else we insert an already 'dead' hash, blocking
|
|
* further use of that particular connection -JM.
|
|
*/
|
|
nf_ct_del_from_dying_or_unconfirmed_list(ct);
|
|
|
|
if (unlikely(nf_ct_is_dying(ct)))
|
|
goto out;
|
|
|
|
/* See if there's one in the list already, including reverse:
|
|
NAT could have grabbed it without realizing, since we're
|
|
not in the hash. If there is, we lost race. */
|
|
hlist_nulls_for_each_entry(h, n, &net->ct.hash[hash], hnnode)
|
|
if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
|
|
&h->tuple) &&
|
|
nf_ct_zone_equal(nf_ct_tuplehash_to_ctrack(h), zone,
|
|
NF_CT_DIRECTION(h)))
|
|
goto out;
|
|
hlist_nulls_for_each_entry(h, n, &net->ct.hash[reply_hash], hnnode)
|
|
if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple,
|
|
&h->tuple) &&
|
|
nf_ct_zone_equal(nf_ct_tuplehash_to_ctrack(h), zone,
|
|
NF_CT_DIRECTION(h)))
|
|
goto out;
|
|
|
|
/* Timer relative to confirmation time, not original
|
|
setting time, otherwise we'd get timer wrap in
|
|
weird delay cases. */
|
|
ct->timeout.expires += jiffies;
|
|
add_timer(&ct->timeout);
|
|
atomic_inc(&ct->ct_general.use);
|
|
ct->status |= IPS_CONFIRMED;
|
|
|
|
/* set conntrack timestamp, if enabled. */
|
|
tstamp = nf_conn_tstamp_find(ct);
|
|
if (tstamp) {
|
|
if (skb->tstamp.tv64 == 0)
|
|
__net_timestamp(skb);
|
|
|
|
tstamp->start = ktime_to_ns(skb->tstamp);
|
|
}
|
|
/* Since the lookup is lockless, hash insertion must be done after
|
|
* starting the timer and setting the CONFIRMED bit. The RCU barriers
|
|
* guarantee that no other CPU can find the conntrack before the above
|
|
* stores are visible.
|
|
*/
|
|
__nf_conntrack_hash_insert(ct, hash, reply_hash);
|
|
nf_conntrack_double_unlock(hash, reply_hash);
|
|
NF_CT_STAT_INC(net, insert);
|
|
local_bh_enable();
|
|
|
|
help = nfct_help(ct);
|
|
if (help && help->helper)
|
|
nf_conntrack_event_cache(IPCT_HELPER, ct);
|
|
|
|
nf_conntrack_event_cache(master_ct(ct) ?
|
|
IPCT_RELATED : IPCT_NEW, ct);
|
|
return NF_ACCEPT;
|
|
|
|
out:
|
|
nf_ct_add_to_dying_list(ct);
|
|
nf_conntrack_double_unlock(hash, reply_hash);
|
|
NF_CT_STAT_INC(net, insert_failed);
|
|
local_bh_enable();
|
|
return NF_DROP;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__nf_conntrack_confirm);
|
|
|
|
/* Returns true if a connection correspondings to the tuple (required
|
|
for NAT). */
|
|
int
|
|
nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple,
|
|
const struct nf_conn *ignored_conntrack)
|
|
{
|
|
struct net *net = nf_ct_net(ignored_conntrack);
|
|
const struct nf_conntrack_zone *zone;
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct hlist_nulls_node *n;
|
|
struct nf_conn *ct;
|
|
unsigned int hash;
|
|
|
|
zone = nf_ct_zone(ignored_conntrack);
|
|
hash = hash_conntrack(net, tuple);
|
|
|
|
/* Disable BHs the entire time since we need to disable them at
|
|
* least once for the stats anyway.
|
|
*/
|
|
rcu_read_lock_bh();
|
|
hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash], hnnode) {
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
if (ct != ignored_conntrack &&
|
|
nf_ct_tuple_equal(tuple, &h->tuple) &&
|
|
nf_ct_zone_equal(ct, zone, NF_CT_DIRECTION(h))) {
|
|
NF_CT_STAT_INC(net, found);
|
|
rcu_read_unlock_bh();
|
|
return 1;
|
|
}
|
|
NF_CT_STAT_INC(net, searched);
|
|
}
|
|
rcu_read_unlock_bh();
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_tuple_taken);
|
|
|
|
#define NF_CT_EVICTION_RANGE 8
|
|
|
|
/* There's a small race here where we may free a just-assured
|
|
connection. Too bad: we're in trouble anyway. */
|
|
static noinline int early_drop(struct net *net, unsigned int _hash)
|
|
{
|
|
/* Use oldest entry, which is roughly LRU */
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct = NULL, *tmp;
|
|
struct hlist_nulls_node *n;
|
|
unsigned int i = 0, cnt = 0;
|
|
int dropped = 0;
|
|
unsigned int hash, sequence;
|
|
spinlock_t *lockp;
|
|
|
|
local_bh_disable();
|
|
restart:
|
|
sequence = read_seqcount_begin(&net->ct.generation);
|
|
hash = hash_bucket(_hash, net);
|
|
for (; i < net->ct.htable_size; i++) {
|
|
lockp = &nf_conntrack_locks[hash % CONNTRACK_LOCKS];
|
|
nf_conntrack_lock(lockp);
|
|
if (read_seqcount_retry(&net->ct.generation, sequence)) {
|
|
spin_unlock(lockp);
|
|
goto restart;
|
|
}
|
|
hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash],
|
|
hnnode) {
|
|
tmp = nf_ct_tuplehash_to_ctrack(h);
|
|
if (!test_bit(IPS_ASSURED_BIT, &tmp->status) &&
|
|
!nf_ct_is_dying(tmp) &&
|
|
atomic_inc_not_zero(&tmp->ct_general.use)) {
|
|
ct = tmp;
|
|
break;
|
|
}
|
|
cnt++;
|
|
}
|
|
|
|
hash = (hash + 1) % net->ct.htable_size;
|
|
spin_unlock(lockp);
|
|
|
|
if (ct || cnt >= NF_CT_EVICTION_RANGE)
|
|
break;
|
|
|
|
}
|
|
local_bh_enable();
|
|
|
|
if (!ct)
|
|
return dropped;
|
|
|
|
if (del_timer(&ct->timeout)) {
|
|
if (nf_ct_delete(ct, 0, 0)) {
|
|
dropped = 1;
|
|
NF_CT_STAT_INC_ATOMIC(net, early_drop);
|
|
}
|
|
}
|
|
nf_ct_put(ct);
|
|
return dropped;
|
|
}
|
|
|
|
void init_nf_conntrack_hash_rnd(void)
|
|
{
|
|
unsigned int rand;
|
|
|
|
/*
|
|
* Why not initialize nf_conntrack_rnd in a "init()" function ?
|
|
* Because there isn't enough entropy when system initializing,
|
|
* and we initialize it as late as possible.
|
|
*/
|
|
do {
|
|
get_random_bytes(&rand, sizeof(rand));
|
|
} while (!rand);
|
|
cmpxchg(&nf_conntrack_hash_rnd, 0, rand);
|
|
}
|
|
|
|
static struct nf_conn *
|
|
__nf_conntrack_alloc(struct net *net,
|
|
const struct nf_conntrack_zone *zone,
|
|
const struct nf_conntrack_tuple *orig,
|
|
const struct nf_conntrack_tuple *repl,
|
|
gfp_t gfp, u32 hash)
|
|
{
|
|
struct nf_conn *ct;
|
|
|
|
if (unlikely(!nf_conntrack_hash_rnd)) {
|
|
init_nf_conntrack_hash_rnd();
|
|
/* recompute the hash as nf_conntrack_hash_rnd is initialized */
|
|
hash = hash_conntrack_raw(orig);
|
|
}
|
|
|
|
/* We don't want any race condition at early drop stage */
|
|
atomic_inc(&net->ct.count);
|
|
|
|
if (nf_conntrack_max &&
|
|
unlikely(atomic_read(&net->ct.count) > nf_conntrack_max)) {
|
|
if (!early_drop(net, hash)) {
|
|
atomic_dec(&net->ct.count);
|
|
net_warn_ratelimited("nf_conntrack: table full, dropping packet\n");
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Do not use kmem_cache_zalloc(), as this cache uses
|
|
* SLAB_DESTROY_BY_RCU.
|
|
*/
|
|
ct = kmem_cache_alloc(net->ct.nf_conntrack_cachep, gfp);
|
|
if (ct == NULL)
|
|
goto out;
|
|
|
|
spin_lock_init(&ct->lock);
|
|
ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
|
|
ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode.pprev = NULL;
|
|
ct->tuplehash[IP_CT_DIR_REPLY].tuple = *repl;
|
|
/* save hash for reusing when confirming */
|
|
*(unsigned long *)(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode.pprev) = hash;
|
|
ct->status = 0;
|
|
/* Don't set timer yet: wait for confirmation */
|
|
setup_timer(&ct->timeout, death_by_timeout, (unsigned long)ct);
|
|
write_pnet(&ct->ct_net, net);
|
|
memset(&ct->__nfct_init_offset[0], 0,
|
|
offsetof(struct nf_conn, proto) -
|
|
offsetof(struct nf_conn, __nfct_init_offset[0]));
|
|
|
|
if (zone && nf_ct_zone_add(ct, GFP_ATOMIC, zone) < 0)
|
|
goto out_free;
|
|
|
|
/* Because we use RCU lookups, we set ct_general.use to zero before
|
|
* this is inserted in any list.
|
|
*/
|
|
atomic_set(&ct->ct_general.use, 0);
|
|
return ct;
|
|
out_free:
|
|
kmem_cache_free(net->ct.nf_conntrack_cachep, ct);
|
|
out:
|
|
atomic_dec(&net->ct.count);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
struct nf_conn *nf_conntrack_alloc(struct net *net,
|
|
const struct nf_conntrack_zone *zone,
|
|
const struct nf_conntrack_tuple *orig,
|
|
const struct nf_conntrack_tuple *repl,
|
|
gfp_t gfp)
|
|
{
|
|
return __nf_conntrack_alloc(net, zone, orig, repl, gfp, 0);
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_alloc);
|
|
|
|
void nf_conntrack_free(struct nf_conn *ct)
|
|
{
|
|
struct net *net = nf_ct_net(ct);
|
|
|
|
/* A freed object has refcnt == 0, that's
|
|
* the golden rule for SLAB_DESTROY_BY_RCU
|
|
*/
|
|
NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 0);
|
|
|
|
nf_ct_ext_destroy(ct);
|
|
nf_ct_ext_free(ct);
|
|
kmem_cache_free(net->ct.nf_conntrack_cachep, ct);
|
|
smp_mb__before_atomic();
|
|
atomic_dec(&net->ct.count);
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_free);
|
|
|
|
|
|
/* Allocate a new conntrack: we return -ENOMEM if classification
|
|
failed due to stress. Otherwise it really is unclassifiable. */
|
|
static struct nf_conntrack_tuple_hash *
|
|
init_conntrack(struct net *net, struct nf_conn *tmpl,
|
|
const struct nf_conntrack_tuple *tuple,
|
|
struct nf_conntrack_l3proto *l3proto,
|
|
struct nf_conntrack_l4proto *l4proto,
|
|
struct sk_buff *skb,
|
|
unsigned int dataoff, u32 hash)
|
|
{
|
|
struct nf_conn *ct;
|
|
struct nf_conn_help *help;
|
|
struct nf_conntrack_tuple repl_tuple;
|
|
struct nf_conntrack_ecache *ecache;
|
|
struct nf_conntrack_expect *exp = NULL;
|
|
const struct nf_conntrack_zone *zone;
|
|
struct nf_conn_timeout *timeout_ext;
|
|
struct nf_conntrack_zone tmp;
|
|
unsigned int *timeouts;
|
|
|
|
if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) {
|
|
pr_debug("Can't invert tuple.\n");
|
|
return NULL;
|
|
}
|
|
|
|
zone = nf_ct_zone_tmpl(tmpl, skb, &tmp);
|
|
ct = __nf_conntrack_alloc(net, zone, tuple, &repl_tuple, GFP_ATOMIC,
|
|
hash);
|
|
if (IS_ERR(ct))
|
|
return (struct nf_conntrack_tuple_hash *)ct;
|
|
|
|
if (tmpl && nfct_synproxy(tmpl)) {
|
|
nfct_seqadj_ext_add(ct);
|
|
nfct_synproxy_ext_add(ct);
|
|
}
|
|
|
|
timeout_ext = tmpl ? nf_ct_timeout_find(tmpl) : NULL;
|
|
if (timeout_ext) {
|
|
timeouts = nf_ct_timeout_data(timeout_ext);
|
|
if (unlikely(!timeouts))
|
|
timeouts = l4proto->get_timeouts(net);
|
|
} else {
|
|
timeouts = l4proto->get_timeouts(net);
|
|
}
|
|
|
|
if (!l4proto->new(ct, skb, dataoff, timeouts)) {
|
|
nf_conntrack_free(ct);
|
|
pr_debug("init conntrack: can't track with proto module\n");
|
|
return NULL;
|
|
}
|
|
|
|
if (timeout_ext)
|
|
nf_ct_timeout_ext_add(ct, rcu_dereference(timeout_ext->timeout),
|
|
GFP_ATOMIC);
|
|
|
|
nf_ct_acct_ext_add(ct, GFP_ATOMIC);
|
|
nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
|
|
nf_ct_labels_ext_add(ct);
|
|
|
|
ecache = tmpl ? nf_ct_ecache_find(tmpl) : NULL;
|
|
nf_ct_ecache_ext_add(ct, ecache ? ecache->ctmask : 0,
|
|
ecache ? ecache->expmask : 0,
|
|
GFP_ATOMIC);
|
|
|
|
local_bh_disable();
|
|
if (net->ct.expect_count) {
|
|
spin_lock(&nf_conntrack_expect_lock);
|
|
exp = nf_ct_find_expectation(net, zone, tuple);
|
|
if (exp) {
|
|
pr_debug("conntrack: expectation arrives ct=%p exp=%p\n",
|
|
ct, exp);
|
|
/* Welcome, Mr. Bond. We've been expecting you... */
|
|
__set_bit(IPS_EXPECTED_BIT, &ct->status);
|
|
/* exp->master safe, refcnt bumped in nf_ct_find_expectation */
|
|
ct->master = exp->master;
|
|
if (exp->helper) {
|
|
help = nf_ct_helper_ext_add(ct, exp->helper,
|
|
GFP_ATOMIC);
|
|
if (help)
|
|
rcu_assign_pointer(help->helper, exp->helper);
|
|
}
|
|
|
|
#ifdef CONFIG_NF_CONNTRACK_MARK
|
|
ct->mark = exp->master->mark;
|
|
#endif
|
|
#ifdef CONFIG_NF_CONNTRACK_SECMARK
|
|
ct->secmark = exp->master->secmark;
|
|
#endif
|
|
NF_CT_STAT_INC(net, expect_new);
|
|
}
|
|
spin_unlock(&nf_conntrack_expect_lock);
|
|
}
|
|
if (!exp) {
|
|
__nf_ct_try_assign_helper(ct, tmpl, GFP_ATOMIC);
|
|
NF_CT_STAT_INC(net, new);
|
|
}
|
|
|
|
/* Now it is inserted into the unconfirmed list, bump refcount */
|
|
nf_conntrack_get(&ct->ct_general);
|
|
nf_ct_add_to_unconfirmed_list(ct);
|
|
|
|
local_bh_enable();
|
|
|
|
if (exp) {
|
|
if (exp->expectfn)
|
|
exp->expectfn(ct, exp);
|
|
nf_ct_expect_put(exp);
|
|
}
|
|
|
|
return &ct->tuplehash[IP_CT_DIR_ORIGINAL];
|
|
}
|
|
|
|
/* On success, returns conntrack ptr, sets skb->nfct and ctinfo */
|
|
static inline struct nf_conn *
|
|
resolve_normal_ct(struct net *net, struct nf_conn *tmpl,
|
|
struct sk_buff *skb,
|
|
unsigned int dataoff,
|
|
u_int16_t l3num,
|
|
u_int8_t protonum,
|
|
struct nf_conntrack_l3proto *l3proto,
|
|
struct nf_conntrack_l4proto *l4proto,
|
|
int *set_reply,
|
|
enum ip_conntrack_info *ctinfo)
|
|
{
|
|
const struct nf_conntrack_zone *zone;
|
|
struct nf_conntrack_tuple tuple;
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conntrack_zone tmp;
|
|
struct nf_conn *ct;
|
|
u32 hash;
|
|
|
|
if (!nf_ct_get_tuple(skb, skb_network_offset(skb),
|
|
dataoff, l3num, protonum, net, &tuple, l3proto,
|
|
l4proto)) {
|
|
pr_debug("resolve_normal_ct: Can't get tuple\n");
|
|
return NULL;
|
|
}
|
|
|
|
/* look for tuple match */
|
|
zone = nf_ct_zone_tmpl(tmpl, skb, &tmp);
|
|
hash = hash_conntrack_raw(&tuple);
|
|
h = __nf_conntrack_find_get(net, zone, &tuple, hash);
|
|
if (!h) {
|
|
h = init_conntrack(net, tmpl, &tuple, l3proto, l4proto,
|
|
skb, dataoff, hash);
|
|
if (!h)
|
|
return NULL;
|
|
if (IS_ERR(h))
|
|
return (void *)h;
|
|
}
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
|
|
/* It exists; we have (non-exclusive) reference. */
|
|
if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) {
|
|
*ctinfo = IP_CT_ESTABLISHED_REPLY;
|
|
/* Please set reply bit if this packet OK */
|
|
*set_reply = 1;
|
|
} else {
|
|
/* Once we've had two way comms, always ESTABLISHED. */
|
|
if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
|
|
pr_debug("nf_conntrack_in: normal packet for %p\n", ct);
|
|
*ctinfo = IP_CT_ESTABLISHED;
|
|
} else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) {
|
|
pr_debug("nf_conntrack_in: related packet for %p\n",
|
|
ct);
|
|
*ctinfo = IP_CT_RELATED;
|
|
} else {
|
|
pr_debug("nf_conntrack_in: new packet for %p\n", ct);
|
|
*ctinfo = IP_CT_NEW;
|
|
}
|
|
*set_reply = 0;
|
|
}
|
|
skb->nfct = &ct->ct_general;
|
|
skb->nfctinfo = *ctinfo;
|
|
return ct;
|
|
}
|
|
|
|
unsigned int
|
|
nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum,
|
|
struct sk_buff *skb)
|
|
{
|
|
struct nf_conn *ct, *tmpl = NULL;
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conntrack_l3proto *l3proto;
|
|
struct nf_conntrack_l4proto *l4proto;
|
|
unsigned int *timeouts;
|
|
unsigned int dataoff;
|
|
u_int8_t protonum;
|
|
int set_reply = 0;
|
|
int ret;
|
|
|
|
if (skb->nfct) {
|
|
/* Previously seen (loopback or untracked)? Ignore. */
|
|
tmpl = (struct nf_conn *)skb->nfct;
|
|
if (!nf_ct_is_template(tmpl)) {
|
|
NF_CT_STAT_INC_ATOMIC(net, ignore);
|
|
return NF_ACCEPT;
|
|
}
|
|
skb->nfct = NULL;
|
|
}
|
|
|
|
/* rcu_read_lock()ed by nf_hook_slow */
|
|
l3proto = __nf_ct_l3proto_find(pf);
|
|
ret = l3proto->get_l4proto(skb, skb_network_offset(skb),
|
|
&dataoff, &protonum);
|
|
if (ret <= 0) {
|
|
pr_debug("not prepared to track yet or error occurred\n");
|
|
NF_CT_STAT_INC_ATOMIC(net, error);
|
|
NF_CT_STAT_INC_ATOMIC(net, invalid);
|
|
ret = -ret;
|
|
goto out;
|
|
}
|
|
|
|
l4proto = __nf_ct_l4proto_find(pf, protonum);
|
|
|
|
/* It may be an special packet, error, unclean...
|
|
* inverse of the return code tells to the netfilter
|
|
* core what to do with the packet. */
|
|
if (l4proto->error != NULL) {
|
|
ret = l4proto->error(net, tmpl, skb, dataoff, &ctinfo,
|
|
pf, hooknum);
|
|
if (ret <= 0) {
|
|
NF_CT_STAT_INC_ATOMIC(net, error);
|
|
NF_CT_STAT_INC_ATOMIC(net, invalid);
|
|
ret = -ret;
|
|
goto out;
|
|
}
|
|
/* ICMP[v6] protocol trackers may assign one conntrack. */
|
|
if (skb->nfct)
|
|
goto out;
|
|
}
|
|
|
|
ct = resolve_normal_ct(net, tmpl, skb, dataoff, pf, protonum,
|
|
l3proto, l4proto, &set_reply, &ctinfo);
|
|
if (!ct) {
|
|
/* Not valid part of a connection */
|
|
NF_CT_STAT_INC_ATOMIC(net, invalid);
|
|
ret = NF_ACCEPT;
|
|
goto out;
|
|
}
|
|
|
|
if (IS_ERR(ct)) {
|
|
/* Too stressed to deal. */
|
|
NF_CT_STAT_INC_ATOMIC(net, drop);
|
|
ret = NF_DROP;
|
|
goto out;
|
|
}
|
|
|
|
NF_CT_ASSERT(skb->nfct);
|
|
|
|
/* Decide what timeout policy we want to apply to this flow. */
|
|
timeouts = nf_ct_timeout_lookup(net, ct, l4proto);
|
|
|
|
ret = l4proto->packet(ct, skb, dataoff, ctinfo, pf, hooknum, timeouts);
|
|
if (ret <= 0) {
|
|
/* Invalid: inverse of the return code tells
|
|
* the netfilter core what to do */
|
|
pr_debug("nf_conntrack_in: Can't track with proto module\n");
|
|
nf_conntrack_put(skb->nfct);
|
|
skb->nfct = NULL;
|
|
NF_CT_STAT_INC_ATOMIC(net, invalid);
|
|
if (ret == -NF_DROP)
|
|
NF_CT_STAT_INC_ATOMIC(net, drop);
|
|
ret = -ret;
|
|
goto out;
|
|
}
|
|
|
|
if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status))
|
|
nf_conntrack_event_cache(IPCT_REPLY, ct);
|
|
out:
|
|
if (tmpl) {
|
|
/* Special case: we have to repeat this hook, assign the
|
|
* template again to this packet. We assume that this packet
|
|
* has no conntrack assigned. This is used by nf_ct_tcp. */
|
|
if (ret == NF_REPEAT)
|
|
skb->nfct = (struct nf_conntrack *)tmpl;
|
|
else
|
|
nf_ct_put(tmpl);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_in);
|
|
|
|
bool nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
|
|
const struct nf_conntrack_tuple *orig)
|
|
{
|
|
bool ret;
|
|
|
|
rcu_read_lock();
|
|
ret = nf_ct_invert_tuple(inverse, orig,
|
|
__nf_ct_l3proto_find(orig->src.l3num),
|
|
__nf_ct_l4proto_find(orig->src.l3num,
|
|
orig->dst.protonum));
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_invert_tuplepr);
|
|
|
|
/* Alter reply tuple (maybe alter helper). This is for NAT, and is
|
|
implicitly racy: see __nf_conntrack_confirm */
|
|
void nf_conntrack_alter_reply(struct nf_conn *ct,
|
|
const struct nf_conntrack_tuple *newreply)
|
|
{
|
|
struct nf_conn_help *help = nfct_help(ct);
|
|
|
|
/* Should be unconfirmed, so not in hash table yet */
|
|
NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
|
|
|
|
pr_debug("Altering reply tuple of %p to ", ct);
|
|
nf_ct_dump_tuple(newreply);
|
|
|
|
ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;
|
|
if (ct->master || (help && !hlist_empty(&help->expectations)))
|
|
return;
|
|
|
|
rcu_read_lock();
|
|
__nf_ct_try_assign_helper(ct, NULL, GFP_ATOMIC);
|
|
rcu_read_unlock();
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply);
|
|
|
|
/* Refresh conntrack for this many jiffies and do accounting if do_acct is 1 */
|
|
void __nf_ct_refresh_acct(struct nf_conn *ct,
|
|
enum ip_conntrack_info ctinfo,
|
|
const struct sk_buff *skb,
|
|
unsigned long extra_jiffies,
|
|
int do_acct)
|
|
{
|
|
NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct);
|
|
NF_CT_ASSERT(skb);
|
|
|
|
/* Only update if this is not a fixed timeout */
|
|
if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status))
|
|
goto acct;
|
|
|
|
/* If not in hash table, timer will not be active yet */
|
|
if (!nf_ct_is_confirmed(ct)) {
|
|
ct->timeout.expires = extra_jiffies;
|
|
} else {
|
|
unsigned long newtime = jiffies + extra_jiffies;
|
|
|
|
/* Only update the timeout if the new timeout is at least
|
|
HZ jiffies from the old timeout. Need del_timer for race
|
|
avoidance (may already be dying). */
|
|
if (newtime - ct->timeout.expires >= HZ)
|
|
mod_timer_pending(&ct->timeout, newtime);
|
|
}
|
|
|
|
acct:
|
|
if (do_acct) {
|
|
struct nf_conn_acct *acct;
|
|
|
|
acct = nf_conn_acct_find(ct);
|
|
if (acct) {
|
|
struct nf_conn_counter *counter = acct->counter;
|
|
|
|
atomic64_inc(&counter[CTINFO2DIR(ctinfo)].packets);
|
|
atomic64_add(skb->len, &counter[CTINFO2DIR(ctinfo)].bytes);
|
|
}
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(__nf_ct_refresh_acct);
|
|
|
|
bool __nf_ct_kill_acct(struct nf_conn *ct,
|
|
enum ip_conntrack_info ctinfo,
|
|
const struct sk_buff *skb,
|
|
int do_acct)
|
|
{
|
|
if (do_acct) {
|
|
struct nf_conn_acct *acct;
|
|
|
|
acct = nf_conn_acct_find(ct);
|
|
if (acct) {
|
|
struct nf_conn_counter *counter = acct->counter;
|
|
|
|
atomic64_inc(&counter[CTINFO2DIR(ctinfo)].packets);
|
|
atomic64_add(skb->len - skb_network_offset(skb),
|
|
&counter[CTINFO2DIR(ctinfo)].bytes);
|
|
}
|
|
}
|
|
|
|
if (del_timer(&ct->timeout)) {
|
|
ct->timeout.function((unsigned long)ct);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__nf_ct_kill_acct);
|
|
|
|
#ifdef CONFIG_NF_CONNTRACK_ZONES
|
|
static struct nf_ct_ext_type nf_ct_zone_extend __read_mostly = {
|
|
.len = sizeof(struct nf_conntrack_zone),
|
|
.align = __alignof__(struct nf_conntrack_zone),
|
|
.id = NF_CT_EXT_ZONE,
|
|
};
|
|
#endif
|
|
|
|
#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
|
|
|
|
#include <linux/netfilter/nfnetlink.h>
|
|
#include <linux/netfilter/nfnetlink_conntrack.h>
|
|
#include <linux/mutex.h>
|
|
|
|
/* Generic function for tcp/udp/sctp/dccp and alike. This needs to be
|
|
* in ip_conntrack_core, since we don't want the protocols to autoload
|
|
* or depend on ctnetlink */
|
|
int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
|
|
const struct nf_conntrack_tuple *tuple)
|
|
{
|
|
if (nla_put_be16(skb, CTA_PROTO_SRC_PORT, tuple->src.u.tcp.port) ||
|
|
nla_put_be16(skb, CTA_PROTO_DST_PORT, tuple->dst.u.tcp.port))
|
|
goto nla_put_failure;
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
return -1;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_port_tuple_to_nlattr);
|
|
|
|
const struct nla_policy nf_ct_port_nla_policy[CTA_PROTO_MAX+1] = {
|
|
[CTA_PROTO_SRC_PORT] = { .type = NLA_U16 },
|
|
[CTA_PROTO_DST_PORT] = { .type = NLA_U16 },
|
|
};
|
|
EXPORT_SYMBOL_GPL(nf_ct_port_nla_policy);
|
|
|
|
int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
|
|
struct nf_conntrack_tuple *t)
|
|
{
|
|
if (!tb[CTA_PROTO_SRC_PORT] || !tb[CTA_PROTO_DST_PORT])
|
|
return -EINVAL;
|
|
|
|
t->src.u.tcp.port = nla_get_be16(tb[CTA_PROTO_SRC_PORT]);
|
|
t->dst.u.tcp.port = nla_get_be16(tb[CTA_PROTO_DST_PORT]);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_to_tuple);
|
|
|
|
int nf_ct_port_nlattr_tuple_size(void)
|
|
{
|
|
return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_tuple_size);
|
|
#endif
|
|
|
|
/* Used by ipt_REJECT and ip6t_REJECT. */
|
|
static void nf_conntrack_attach(struct sk_buff *nskb, const struct sk_buff *skb)
|
|
{
|
|
struct nf_conn *ct;
|
|
enum ip_conntrack_info ctinfo;
|
|
|
|
/* This ICMP is in reverse direction to the packet which caused it */
|
|
ct = nf_ct_get(skb, &ctinfo);
|
|
if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL)
|
|
ctinfo = IP_CT_RELATED_REPLY;
|
|
else
|
|
ctinfo = IP_CT_RELATED;
|
|
|
|
/* Attach to new skbuff, and increment count */
|
|
nskb->nfct = &ct->ct_general;
|
|
nskb->nfctinfo = ctinfo;
|
|
nf_conntrack_get(nskb->nfct);
|
|
}
|
|
|
|
/* Bring out ya dead! */
|
|
static struct nf_conn *
|
|
get_next_corpse(struct net *net, int (*iter)(struct nf_conn *i, void *data),
|
|
void *data, unsigned int *bucket)
|
|
{
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct;
|
|
struct hlist_nulls_node *n;
|
|
int cpu;
|
|
spinlock_t *lockp;
|
|
|
|
for (; *bucket < net->ct.htable_size; (*bucket)++) {
|
|
lockp = &nf_conntrack_locks[*bucket % CONNTRACK_LOCKS];
|
|
local_bh_disable();
|
|
nf_conntrack_lock(lockp);
|
|
if (*bucket < net->ct.htable_size) {
|
|
hlist_nulls_for_each_entry(h, n, &net->ct.hash[*bucket], hnnode) {
|
|
if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
|
|
continue;
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
if (iter(ct, data))
|
|
goto found;
|
|
}
|
|
}
|
|
spin_unlock(lockp);
|
|
local_bh_enable();
|
|
}
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct ct_pcpu *pcpu = per_cpu_ptr(net->ct.pcpu_lists, cpu);
|
|
|
|
spin_lock_bh(&pcpu->lock);
|
|
hlist_nulls_for_each_entry(h, n, &pcpu->unconfirmed, hnnode) {
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
if (iter(ct, data))
|
|
set_bit(IPS_DYING_BIT, &ct->status);
|
|
}
|
|
spin_unlock_bh(&pcpu->lock);
|
|
}
|
|
return NULL;
|
|
found:
|
|
atomic_inc(&ct->ct_general.use);
|
|
spin_unlock(lockp);
|
|
local_bh_enable();
|
|
return ct;
|
|
}
|
|
|
|
void nf_ct_iterate_cleanup(struct net *net,
|
|
int (*iter)(struct nf_conn *i, void *data),
|
|
void *data, u32 portid, int report)
|
|
{
|
|
struct nf_conn *ct;
|
|
unsigned int bucket = 0;
|
|
|
|
while ((ct = get_next_corpse(net, iter, data, &bucket)) != NULL) {
|
|
/* Time to push up daises... */
|
|
if (del_timer(&ct->timeout))
|
|
nf_ct_delete(ct, portid, report);
|
|
|
|
/* ... else the timer will get him soon. */
|
|
|
|
nf_ct_put(ct);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_iterate_cleanup);
|
|
|
|
static int kill_all(struct nf_conn *i, void *data)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
void nf_ct_free_hashtable(void *hash, unsigned int size)
|
|
{
|
|
if (is_vmalloc_addr(hash))
|
|
vfree(hash);
|
|
else
|
|
free_pages((unsigned long)hash,
|
|
get_order(sizeof(struct hlist_head) * size));
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_free_hashtable);
|
|
|
|
static int untrack_refs(void)
|
|
{
|
|
int cnt = 0, cpu;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu);
|
|
|
|
cnt += atomic_read(&ct->ct_general.use) - 1;
|
|
}
|
|
return cnt;
|
|
}
|
|
|
|
void nf_conntrack_cleanup_start(void)
|
|
{
|
|
RCU_INIT_POINTER(ip_ct_attach, NULL);
|
|
}
|
|
|
|
void nf_conntrack_cleanup_end(void)
|
|
{
|
|
RCU_INIT_POINTER(nf_ct_destroy, NULL);
|
|
while (untrack_refs() > 0)
|
|
schedule();
|
|
|
|
#ifdef CONFIG_NF_CONNTRACK_ZONES
|
|
nf_ct_extend_unregister(&nf_ct_zone_extend);
|
|
#endif
|
|
nf_conntrack_proto_fini();
|
|
nf_conntrack_seqadj_fini();
|
|
nf_conntrack_labels_fini();
|
|
nf_conntrack_helper_fini();
|
|
nf_conntrack_timeout_fini();
|
|
nf_conntrack_ecache_fini();
|
|
nf_conntrack_tstamp_fini();
|
|
nf_conntrack_acct_fini();
|
|
nf_conntrack_expect_fini();
|
|
}
|
|
|
|
/*
|
|
* Mishearing the voices in his head, our hero wonders how he's
|
|
* supposed to kill the mall.
|
|
*/
|
|
void nf_conntrack_cleanup_net(struct net *net)
|
|
{
|
|
LIST_HEAD(single);
|
|
|
|
list_add(&net->exit_list, &single);
|
|
nf_conntrack_cleanup_net_list(&single);
|
|
}
|
|
|
|
void nf_conntrack_cleanup_net_list(struct list_head *net_exit_list)
|
|
{
|
|
int busy;
|
|
struct net *net;
|
|
|
|
/*
|
|
* This makes sure all current packets have passed through
|
|
* netfilter framework. Roll on, two-stage module
|
|
* delete...
|
|
*/
|
|
synchronize_net();
|
|
i_see_dead_people:
|
|
busy = 0;
|
|
list_for_each_entry(net, net_exit_list, exit_list) {
|
|
nf_ct_iterate_cleanup(net, kill_all, NULL, 0, 0);
|
|
if (atomic_read(&net->ct.count) != 0)
|
|
busy = 1;
|
|
}
|
|
if (busy) {
|
|
schedule();
|
|
goto i_see_dead_people;
|
|
}
|
|
|
|
list_for_each_entry(net, net_exit_list, exit_list) {
|
|
nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size);
|
|
nf_conntrack_proto_pernet_fini(net);
|
|
nf_conntrack_helper_pernet_fini(net);
|
|
nf_conntrack_ecache_pernet_fini(net);
|
|
nf_conntrack_tstamp_pernet_fini(net);
|
|
nf_conntrack_acct_pernet_fini(net);
|
|
nf_conntrack_expect_pernet_fini(net);
|
|
kmem_cache_destroy(net->ct.nf_conntrack_cachep);
|
|
kfree(net->ct.slabname);
|
|
free_percpu(net->ct.stat);
|
|
free_percpu(net->ct.pcpu_lists);
|
|
}
|
|
}
|
|
|
|
void *nf_ct_alloc_hashtable(unsigned int *sizep, int nulls)
|
|
{
|
|
struct hlist_nulls_head *hash;
|
|
unsigned int nr_slots, i;
|
|
size_t sz;
|
|
|
|
BUILD_BUG_ON(sizeof(struct hlist_nulls_head) != sizeof(struct hlist_head));
|
|
nr_slots = *sizep = roundup(*sizep, PAGE_SIZE / sizeof(struct hlist_nulls_head));
|
|
sz = nr_slots * sizeof(struct hlist_nulls_head);
|
|
hash = (void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO,
|
|
get_order(sz));
|
|
if (!hash)
|
|
hash = vzalloc(sz);
|
|
|
|
if (hash && nulls)
|
|
for (i = 0; i < nr_slots; i++)
|
|
INIT_HLIST_NULLS_HEAD(&hash[i], i);
|
|
|
|
return hash;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_alloc_hashtable);
|
|
|
|
int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp)
|
|
{
|
|
int i, bucket, rc;
|
|
unsigned int hashsize, old_size;
|
|
struct hlist_nulls_head *hash, *old_hash;
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct;
|
|
|
|
if (current->nsproxy->net_ns != &init_net)
|
|
return -EOPNOTSUPP;
|
|
|
|
/* On boot, we can set this without any fancy locking. */
|
|
if (!nf_conntrack_htable_size)
|
|
return param_set_uint(val, kp);
|
|
|
|
rc = kstrtouint(val, 0, &hashsize);
|
|
if (rc)
|
|
return rc;
|
|
if (!hashsize)
|
|
return -EINVAL;
|
|
|
|
hash = nf_ct_alloc_hashtable(&hashsize, 1);
|
|
if (!hash)
|
|
return -ENOMEM;
|
|
|
|
local_bh_disable();
|
|
nf_conntrack_all_lock();
|
|
write_seqcount_begin(&init_net.ct.generation);
|
|
|
|
/* Lookups in the old hash might happen in parallel, which means we
|
|
* might get false negatives during connection lookup. New connections
|
|
* created because of a false negative won't make it into the hash
|
|
* though since that required taking the locks.
|
|
*/
|
|
|
|
for (i = 0; i < init_net.ct.htable_size; i++) {
|
|
while (!hlist_nulls_empty(&init_net.ct.hash[i])) {
|
|
h = hlist_nulls_entry(init_net.ct.hash[i].first,
|
|
struct nf_conntrack_tuple_hash, hnnode);
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
hlist_nulls_del_rcu(&h->hnnode);
|
|
bucket = __hash_conntrack(&h->tuple, hashsize);
|
|
hlist_nulls_add_head_rcu(&h->hnnode, &hash[bucket]);
|
|
}
|
|
}
|
|
old_size = init_net.ct.htable_size;
|
|
old_hash = init_net.ct.hash;
|
|
|
|
init_net.ct.htable_size = nf_conntrack_htable_size = hashsize;
|
|
init_net.ct.hash = hash;
|
|
|
|
write_seqcount_end(&init_net.ct.generation);
|
|
nf_conntrack_all_unlock();
|
|
local_bh_enable();
|
|
|
|
nf_ct_free_hashtable(old_hash, old_size);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize);
|
|
|
|
module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
|
|
&nf_conntrack_htable_size, 0600);
|
|
|
|
void nf_ct_untracked_status_or(unsigned long bits)
|
|
{
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu)
|
|
per_cpu(nf_conntrack_untracked, cpu).status |= bits;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_untracked_status_or);
|
|
|
|
int nf_conntrack_init_start(void)
|
|
{
|
|
int max_factor = 8;
|
|
int i, ret, cpu;
|
|
|
|
for (i = 0; i < CONNTRACK_LOCKS; i++)
|
|
spin_lock_init(&nf_conntrack_locks[i]);
|
|
|
|
if (!nf_conntrack_htable_size) {
|
|
/* Idea from tcp.c: use 1/16384 of memory.
|
|
* On i386: 32MB machine has 512 buckets.
|
|
* >= 1GB machines have 16384 buckets.
|
|
* >= 4GB machines have 65536 buckets.
|
|
*/
|
|
nf_conntrack_htable_size
|
|
= (((totalram_pages << PAGE_SHIFT) / 16384)
|
|
/ sizeof(struct hlist_head));
|
|
if (totalram_pages > (4 * (1024 * 1024 * 1024 / PAGE_SIZE)))
|
|
nf_conntrack_htable_size = 65536;
|
|
else if (totalram_pages > (1024 * 1024 * 1024 / PAGE_SIZE))
|
|
nf_conntrack_htable_size = 16384;
|
|
if (nf_conntrack_htable_size < 32)
|
|
nf_conntrack_htable_size = 32;
|
|
|
|
/* Use a max. factor of four by default to get the same max as
|
|
* with the old struct list_heads. When a table size is given
|
|
* we use the old value of 8 to avoid reducing the max.
|
|
* entries. */
|
|
max_factor = 4;
|
|
}
|
|
nf_conntrack_max = max_factor * nf_conntrack_htable_size;
|
|
|
|
printk(KERN_INFO "nf_conntrack version %s (%u buckets, %d max)\n",
|
|
NF_CONNTRACK_VERSION, nf_conntrack_htable_size,
|
|
nf_conntrack_max);
|
|
|
|
ret = nf_conntrack_expect_init();
|
|
if (ret < 0)
|
|
goto err_expect;
|
|
|
|
ret = nf_conntrack_acct_init();
|
|
if (ret < 0)
|
|
goto err_acct;
|
|
|
|
ret = nf_conntrack_tstamp_init();
|
|
if (ret < 0)
|
|
goto err_tstamp;
|
|
|
|
ret = nf_conntrack_ecache_init();
|
|
if (ret < 0)
|
|
goto err_ecache;
|
|
|
|
ret = nf_conntrack_timeout_init();
|
|
if (ret < 0)
|
|
goto err_timeout;
|
|
|
|
ret = nf_conntrack_helper_init();
|
|
if (ret < 0)
|
|
goto err_helper;
|
|
|
|
ret = nf_conntrack_labels_init();
|
|
if (ret < 0)
|
|
goto err_labels;
|
|
|
|
ret = nf_conntrack_seqadj_init();
|
|
if (ret < 0)
|
|
goto err_seqadj;
|
|
|
|
#ifdef CONFIG_NF_CONNTRACK_ZONES
|
|
ret = nf_ct_extend_register(&nf_ct_zone_extend);
|
|
if (ret < 0)
|
|
goto err_extend;
|
|
#endif
|
|
ret = nf_conntrack_proto_init();
|
|
if (ret < 0)
|
|
goto err_proto;
|
|
|
|
/* Set up fake conntrack: to never be deleted, not in any hashes */
|
|
for_each_possible_cpu(cpu) {
|
|
struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu);
|
|
write_pnet(&ct->ct_net, &init_net);
|
|
atomic_set(&ct->ct_general.use, 1);
|
|
}
|
|
/* - and look it like as a confirmed connection */
|
|
nf_ct_untracked_status_or(IPS_CONFIRMED | IPS_UNTRACKED);
|
|
return 0;
|
|
|
|
err_proto:
|
|
#ifdef CONFIG_NF_CONNTRACK_ZONES
|
|
nf_ct_extend_unregister(&nf_ct_zone_extend);
|
|
err_extend:
|
|
#endif
|
|
nf_conntrack_seqadj_fini();
|
|
err_seqadj:
|
|
nf_conntrack_labels_fini();
|
|
err_labels:
|
|
nf_conntrack_helper_fini();
|
|
err_helper:
|
|
nf_conntrack_timeout_fini();
|
|
err_timeout:
|
|
nf_conntrack_ecache_fini();
|
|
err_ecache:
|
|
nf_conntrack_tstamp_fini();
|
|
err_tstamp:
|
|
nf_conntrack_acct_fini();
|
|
err_acct:
|
|
nf_conntrack_expect_fini();
|
|
err_expect:
|
|
return ret;
|
|
}
|
|
|
|
void nf_conntrack_init_end(void)
|
|
{
|
|
/* For use by REJECT target */
|
|
RCU_INIT_POINTER(ip_ct_attach, nf_conntrack_attach);
|
|
RCU_INIT_POINTER(nf_ct_destroy, destroy_conntrack);
|
|
}
|
|
|
|
/*
|
|
* We need to use special "null" values, not used in hash table
|
|
*/
|
|
#define UNCONFIRMED_NULLS_VAL ((1<<30)+0)
|
|
#define DYING_NULLS_VAL ((1<<30)+1)
|
|
#define TEMPLATE_NULLS_VAL ((1<<30)+2)
|
|
|
|
int nf_conntrack_init_net(struct net *net)
|
|
{
|
|
int ret = -ENOMEM;
|
|
int cpu;
|
|
|
|
atomic_set(&net->ct.count, 0);
|
|
seqcount_init(&net->ct.generation);
|
|
|
|
net->ct.pcpu_lists = alloc_percpu(struct ct_pcpu);
|
|
if (!net->ct.pcpu_lists)
|
|
goto err_stat;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct ct_pcpu *pcpu = per_cpu_ptr(net->ct.pcpu_lists, cpu);
|
|
|
|
spin_lock_init(&pcpu->lock);
|
|
INIT_HLIST_NULLS_HEAD(&pcpu->unconfirmed, UNCONFIRMED_NULLS_VAL);
|
|
INIT_HLIST_NULLS_HEAD(&pcpu->dying, DYING_NULLS_VAL);
|
|
}
|
|
|
|
net->ct.stat = alloc_percpu(struct ip_conntrack_stat);
|
|
if (!net->ct.stat)
|
|
goto err_pcpu_lists;
|
|
|
|
net->ct.slabname = kasprintf(GFP_KERNEL, "nf_conntrack_%p", net);
|
|
if (!net->ct.slabname)
|
|
goto err_slabname;
|
|
|
|
net->ct.nf_conntrack_cachep = kmem_cache_create(net->ct.slabname,
|
|
sizeof(struct nf_conn), 0,
|
|
SLAB_DESTROY_BY_RCU, NULL);
|
|
if (!net->ct.nf_conntrack_cachep) {
|
|
printk(KERN_ERR "Unable to create nf_conn slab cache\n");
|
|
goto err_cache;
|
|
}
|
|
|
|
net->ct.htable_size = nf_conntrack_htable_size;
|
|
net->ct.hash = nf_ct_alloc_hashtable(&net->ct.htable_size, 1);
|
|
if (!net->ct.hash) {
|
|
printk(KERN_ERR "Unable to create nf_conntrack_hash\n");
|
|
goto err_hash;
|
|
}
|
|
ret = nf_conntrack_expect_pernet_init(net);
|
|
if (ret < 0)
|
|
goto err_expect;
|
|
ret = nf_conntrack_acct_pernet_init(net);
|
|
if (ret < 0)
|
|
goto err_acct;
|
|
ret = nf_conntrack_tstamp_pernet_init(net);
|
|
if (ret < 0)
|
|
goto err_tstamp;
|
|
ret = nf_conntrack_ecache_pernet_init(net);
|
|
if (ret < 0)
|
|
goto err_ecache;
|
|
ret = nf_conntrack_helper_pernet_init(net);
|
|
if (ret < 0)
|
|
goto err_helper;
|
|
ret = nf_conntrack_proto_pernet_init(net);
|
|
if (ret < 0)
|
|
goto err_proto;
|
|
return 0;
|
|
|
|
err_proto:
|
|
nf_conntrack_helper_pernet_fini(net);
|
|
err_helper:
|
|
nf_conntrack_ecache_pernet_fini(net);
|
|
err_ecache:
|
|
nf_conntrack_tstamp_pernet_fini(net);
|
|
err_tstamp:
|
|
nf_conntrack_acct_pernet_fini(net);
|
|
err_acct:
|
|
nf_conntrack_expect_pernet_fini(net);
|
|
err_expect:
|
|
nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size);
|
|
err_hash:
|
|
kmem_cache_destroy(net->ct.nf_conntrack_cachep);
|
|
err_cache:
|
|
kfree(net->ct.slabname);
|
|
err_slabname:
|
|
free_percpu(net->ct.stat);
|
|
err_pcpu_lists:
|
|
free_percpu(net->ct.pcpu_lists);
|
|
err_stat:
|
|
return ret;
|
|
}
|