[PATCH nf-next-2.6] conntrack: IPS_UNTRACKED bit
From: Eric Dumazet <hidden>
Date: 2010-06-04 16:25:37
Also in:
netfilter-devel
Subsystem:
netfilter, networking [general], the rest · Maintainers:
Pablo Neira Ayuso, Florian Westphal, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Le vendredi 04 juin 2010 à 14:36 +0200, Eric Dumazet a écrit :
Le vendredi 04 juin 2010 à 14:29 +0200, Patrick McHardy a écrit :quoted
Changli Gao wrote:quoted
On Fri, Jun 4, 2010 at 7:40 PM, Patrick McHardy [off-list ref] wrote:quoted
Eric Dumazet wrote:quoted
Obviously, an IPS_UNTRACKED bit would be much easier to implement. Would it be acceptable ?That also would be fine. However the main idea behind using a nfctinfo bit was that we wouldn't need the untracked conntrack anymore at all. But I guess a per-cpu untrack conntrack would already be an improvement over the current situation.I think Eric didn't mean ip_conntrack_info but ip_conntrack_status bit. Since we have had a IPS_TEMPLATE bit, I think another IPS_UNTRACKED bit is also acceptable.Yes, of course. But using one of these bits implies that we'd still have the untracked conntrack.Yes, it was my idea, with a per_cpu untracked conntrack. I'll submit a patch, thanks.
Here is first part, introducing IPS_UNTRACKED bit and various helpers to abstract nf_conntrack_untracked access. I'll cook second patch in a couple of hours for per_cpu conversion. Thanks ! [PATCH nf-next-2.6] conntrack: IPS_UNTRACKED bit NOTRACK makes all cpus share a cache line on nf_conntrack_untracked twice per packet. This is bad for performance. __read_mostly annotation is also a bad choice. This patch introduces IPS_UNTRACKED bit so that we can use later a per_cpu untrack structure more easily. A new helper, nf_ct_untracked_get() returns a pointer to nf_conntrack_untracked. Another one, nf_ct_untracked_status_or() is used by nf_nat_init() to add IPS_NAT_DONE_MASK bits to untracked status. nf_ct_is_untracked() prototype is changed to work on a nf_conn pointer. Signed-off-by: Eric Dumazet <redacted> --- include/linux/netfilter/nf_conntrack_common.h | 4 ++++ include/net/netfilter/nf_conntrack.h | 12 +++++++++--- include/net/netfilter/nf_conntrack_core.h | 2 +- net/ipv4/netfilter/nf_nat_core.c | 2 +- net/ipv4/netfilter/nf_nat_standalone.c | 2 +- net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c | 2 +- net/netfilter/nf_conntrack_core.c | 11 ++++++++--- net/netfilter/nf_conntrack_netlink.c | 2 +- net/netfilter/xt_CT.c | 4 ++-- net/netfilter/xt_NOTRACK.c | 2 +- net/netfilter/xt_TEE.c | 4 ++-- net/netfilter/xt_cluster.c | 2 +- net/netfilter/xt_conntrack.c | 11 ++++++----- net/netfilter/xt_socket.c | 2 +- net/netfilter/xt_state.c | 14 ++++++++------ 15 files changed, 47 insertions(+), 29 deletions(-)
diff --git a/include/linux/netfilter/nf_conntrack_common.h b/include/linux/netfilter/nf_conntrack_common.h
index 14e6d32..1afd18c 100644
--- a/include/linux/netfilter/nf_conntrack_common.h
+++ b/include/linux/netfilter/nf_conntrack_common.h@@ -76,6 +76,10 @@ enum ip_conntrack_status { /* Conntrack is a template */ IPS_TEMPLATE_BIT = 11, IPS_TEMPLATE = (1 << IPS_TEMPLATE_BIT), + + /* Conntrack is a fake untracked entry */ + IPS_UNTRACKED_BIT = 12, + IPS_UNTRACKED = (1 << IPS_UNTRACKED_BIT), }; /* Connection tracking event types */
diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index bde095f..3bc38c7 100644
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h@@ -261,7 +261,13 @@ extern s16 (*nf_ct_nat_offset)(const struct nf_conn *ct, u32 seq); /* Fake conntrack entry for untracked connections */ -extern struct nf_conn nf_conntrack_untracked; +static inline struct nf_conn *nf_ct_untracked_get(void) +{ + extern struct nf_conn nf_conntrack_untracked; + + return &nf_conntrack_untracked; +} +extern void nf_ct_untracked_status_or(unsigned long bits); /* Iterate over all conntracks: if iter returns true, it's deleted. */ extern void
@@ -289,9 +295,9 @@ static inline int nf_ct_is_dying(struct nf_conn *ct) return test_bit(IPS_DYING_BIT, &ct->status); } -static inline int nf_ct_is_untracked(const struct sk_buff *skb) +static inline int nf_ct_is_untracked(const struct nf_conn *ct) { - return (skb->nfct == &nf_conntrack_untracked.ct_general); + return test_bit(IPS_UNTRACKED_BIT, &ct->status); } extern int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp);
diff --git a/include/net/netfilter/nf_conntrack_core.h b/include/net/netfilter/nf_conntrack_core.h
index 3d7524f..aced085 100644
--- a/include/net/netfilter/nf_conntrack_core.h
+++ b/include/net/netfilter/nf_conntrack_core.h@@ -60,7 +60,7 @@ static inline int nf_conntrack_confirm(struct sk_buff *skb) struct nf_conn *ct = (struct nf_conn *)skb->nfct; int ret = NF_ACCEPT; - if (ct && ct != &nf_conntrack_untracked) { + if (ct && !nf_ct_is_untracked(ct)) { if (!nf_ct_is_confirmed(ct)) ret = __nf_conntrack_confirm(skb); if (likely(ret == NF_ACCEPT))
diff --git a/net/ipv4/netfilter/nf_nat_core.c b/net/ipv4/netfilter/nf_nat_core.c
index 4f8bddb..c7719b2 100644
--- a/net/ipv4/netfilter/nf_nat_core.c
+++ b/net/ipv4/netfilter/nf_nat_core.c@@ -742,7 +742,7 @@ static int __init nf_nat_init(void) spin_unlock_bh(&nf_nat_lock); /* Initialize fake conntrack so that NAT will skip it */ - nf_conntrack_untracked.status |= IPS_NAT_DONE_MASK; + nf_ct_untracked_status_or(IPS_NAT_DONE_MASK); l3proto = nf_ct_l3proto_find_get((u_int16_t)AF_INET);
diff --git a/net/ipv4/netfilter/nf_nat_standalone.c b/net/ipv4/netfilter/nf_nat_standalone.c
index beb2581..6723c68 100644
--- a/net/ipv4/netfilter/nf_nat_standalone.c
+++ b/net/ipv4/netfilter/nf_nat_standalone.c@@ -98,7 +98,7 @@ nf_nat_fn(unsigned int hooknum, return NF_ACCEPT; /* Don't try to NAT if this packet is not conntracked */ - if (ct == &nf_conntrack_untracked) + if (nf_ct_is_untracked(ct)) return NF_ACCEPT; nat = nfct_nat(ct);
diff --git a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
index 9be8177..1df3c8b 100644
--- a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c@@ -208,7 +208,7 @@ icmpv6_error(struct net *net, struct nf_conn *tmpl, type = icmp6h->icmp6_type - 130; if (type >= 0 && type < sizeof(noct_valid_new) && noct_valid_new[type]) { - skb->nfct = &nf_conntrack_untracked.ct_general; + skb->nfct = &nf_ct_untracked_get()->ct_general; skb->nfctinfo = IP_CT_NEW; nf_conntrack_get(skb->nfct); return NF_ACCEPT;
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index eeeb8bc..6c1da21 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c@@ -62,7 +62,7 @@ EXPORT_SYMBOL_GPL(nf_conntrack_htable_size); unsigned int nf_conntrack_max __read_mostly; EXPORT_SYMBOL_GPL(nf_conntrack_max); -struct nf_conn nf_conntrack_untracked __read_mostly; +struct nf_conn nf_conntrack_untracked; EXPORT_SYMBOL_GPL(nf_conntrack_untracked); static int nf_conntrack_hash_rnd_initted;
@@ -1321,6 +1321,12 @@ 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) +{ + nf_conntrack_untracked.status |= bits; +} +EXPORT_SYMBOL_GPL(nf_ct_untracked_status_or); + static int nf_conntrack_init_init_net(void) { int max_factor = 8;
@@ -1368,8 +1374,7 @@ static int nf_conntrack_init_init_net(void) #endif atomic_set(&nf_conntrack_untracked.ct_general.use, 1); /* - and look it like as a confirmed connection */ - set_bit(IPS_CONFIRMED_BIT, &nf_conntrack_untracked.status); - + nf_ct_untracked_status_or(IPS_CONFIRMED | IPS_UNTRACKED); return 0; #ifdef CONFIG_NF_CONNTRACK_ZONES
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index c42ff6a..5bae1cd 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c@@ -480,7 +480,7 @@ ctnetlink_conntrack_event(unsigned int events, struct nf_ct_event *item) int err; /* ignore our fake conntrack entry */ - if (ct == &nf_conntrack_untracked) + if (nf_ct_is_untracked(ct)) return 0; if (events & (1 << IPCT_DESTROY)) {
diff --git a/net/netfilter/xt_CT.c b/net/netfilter/xt_CT.c
index 562bf32..0cb6053 100644
--- a/net/netfilter/xt_CT.c
+++ b/net/netfilter/xt_CT.c@@ -67,7 +67,7 @@ static int xt_ct_tg_check(const struct xt_tgchk_param *par) return -EINVAL; if (info->flags & XT_CT_NOTRACK) { - ct = &nf_conntrack_untracked; + ct = nf_ct_untracked_get(); atomic_inc(&ct->ct_general.use); goto out; }
@@ -132,7 +132,7 @@ static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par) struct nf_conn *ct = info->ct; struct nf_conn_help *help; - if (ct != &nf_conntrack_untracked) { + if (!nf_ct_is_untracked(ct)) { help = nfct_help(ct); if (help) module_put(help->helper->me);
diff --git a/net/netfilter/xt_NOTRACK.c b/net/netfilter/xt_NOTRACK.c
index 512b912..9d78218 100644
--- a/net/netfilter/xt_NOTRACK.c
+++ b/net/netfilter/xt_NOTRACK.c@@ -23,7 +23,7 @@ notrack_tg(struct sk_buff *skb, const struct xt_action_param *par) If there is a real ct entry correspondig to this packet, it'll hang aroun till timing out. We don't deal with it for performance reasons. JK */ - skb->nfct = &nf_conntrack_untracked.ct_general; + skb->nfct = &nf_ct_untracked_get()->ct_general; skb->nfctinfo = IP_CT_NEW; nf_conntrack_get(skb->nfct);
diff --git a/net/netfilter/xt_TEE.c b/net/netfilter/xt_TEE.c
index 859d9fd..7a11826 100644
--- a/net/netfilter/xt_TEE.c
+++ b/net/netfilter/xt_TEE.c@@ -104,7 +104,7 @@ tee_tg4(struct sk_buff *skb, const struct xt_action_param *par) #ifdef WITH_CONNTRACK /* Avoid counting cloned packets towards the original connection. */ nf_conntrack_put(skb->nfct); - skb->nfct = &nf_conntrack_untracked.ct_general; + skb->nfct = &nf_ct_untracked_get()->ct_general; skb->nfctinfo = IP_CT_NEW; nf_conntrack_get(skb->nfct); #endif
@@ -177,7 +177,7 @@ tee_tg6(struct sk_buff *skb, const struct xt_action_param *par) #ifdef WITH_CONNTRACK nf_conntrack_put(skb->nfct); - skb->nfct = &nf_conntrack_untracked.ct_general; + skb->nfct = &nf_ct_untracked_get()->ct_general; skb->nfctinfo = IP_CT_NEW; nf_conntrack_get(skb->nfct); #endif
diff --git a/net/netfilter/xt_cluster.c b/net/netfilter/xt_cluster.c
index 30b95a1..f4af1bf 100644
--- a/net/netfilter/xt_cluster.c
+++ b/net/netfilter/xt_cluster.c@@ -120,7 +120,7 @@ xt_cluster_mt(const struct sk_buff *skb, struct xt_action_param *par) if (ct == NULL) return false; - if (ct == &nf_conntrack_untracked) + if (nf_ct_is_untracked(ct)) return false; if (ct->master)
diff --git a/net/netfilter/xt_conntrack.c b/net/netfilter/xt_conntrack.c
index 39681f1..e536710 100644
--- a/net/netfilter/xt_conntrack.c
+++ b/net/netfilter/xt_conntrack.c@@ -123,11 +123,12 @@ conntrack_mt(const struct sk_buff *skb, struct xt_action_param *par, ct = nf_ct_get(skb, &ctinfo); - if (ct == &nf_conntrack_untracked) - statebit = XT_CONNTRACK_STATE_UNTRACKED; - else if (ct != NULL) - statebit = XT_CONNTRACK_STATE_BIT(ctinfo); - else + if (ct) { + if (nf_ct_is_untracked(ct)) + statebit = XT_CONNTRACK_STATE_UNTRACKED; + else + statebit = XT_CONNTRACK_STATE_BIT(ctinfo); + } else statebit = XT_CONNTRACK_STATE_INVALID; if (info->match_flags & XT_CONNTRACK_STATE) {
diff --git a/net/netfilter/xt_socket.c b/net/netfilter/xt_socket.c
index 3d54c23..1ca8990 100644
--- a/net/netfilter/xt_socket.c
+++ b/net/netfilter/xt_socket.c@@ -127,7 +127,7 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par, * reply packet of an established SNAT-ted connection. */ ct = nf_ct_get(skb, &ctinfo); - if (ct && (ct != &nf_conntrack_untracked) && + if (ct && !nf_ct_is_untracked(ct) && ((iph->protocol != IPPROTO_ICMP && ctinfo == IP_CT_IS_REPLY + IP_CT_ESTABLISHED) || (iph->protocol == IPPROTO_ICMP &&
diff --git a/net/netfilter/xt_state.c b/net/netfilter/xt_state.c
index e12e053..a507922 100644
--- a/net/netfilter/xt_state.c
+++ b/net/netfilter/xt_state.c@@ -26,14 +26,16 @@ state_mt(const struct sk_buff *skb, struct xt_action_param *par) const struct xt_state_info *sinfo = par->matchinfo; enum ip_conntrack_info ctinfo; unsigned int statebit; + struct nf_conn *ct = nf_ct_get(skb, &ctinfo); - if (nf_ct_is_untracked(skb)) - statebit = XT_STATE_UNTRACKED; - else if (!nf_ct_get(skb, &ctinfo)) + if (!ct) statebit = XT_STATE_INVALID; - else - statebit = XT_STATE_BIT(ctinfo); - + else { + if (nf_ct_is_untracked(ct)) + statebit = XT_STATE_UNTRACKED; + else + statebit = XT_STATE_BIT(ctinfo); + } return (sinfo->statemask & statebit); }