From 2248bcfcd8fb622ec88b8587d0c1f139635ffd2e Mon Sep 17 00:00:00 2001
From: Patrick McHardy <kaber@trash.net>
Date: Tue, 6 Sep 2005 15:06:42 -0700
Subject: [PATCH] [NETFILTER]: Add support for permanent expectations
A permanent expectation exists until timeing out and can expect
multiple related connections.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/linux/netfilter_ipv4/ip_conntrack.h | 5 +++++
net/ipv4/netfilter/ip_conntrack_amanda.c | 1 +
net/ipv4/netfilter/ip_conntrack_core.c | 12 ++++++++----
net/ipv4/netfilter/ip_conntrack_ftp.c | 1 +
net/ipv4/netfilter/ip_conntrack_irc.c | 1 +
net/ipv4/netfilter/ip_conntrack_netlink.c | 1 +
net/ipv4/netfilter/ip_conntrack_tftp.c | 1 +
7 files changed, 18 insertions(+), 4 deletions(-)
diff --git a/include/linux/netfilter_ipv4/ip_conntrack.h b/include/linux/netfilter_ipv4/ip_conntrack.h
index 088742befe49..7e033e9271a8 100644
--- a/include/linux/netfilter_ipv4/ip_conntrack.h
+++ b/include/linux/netfilter_ipv4/ip_conntrack.h
@@ -263,6 +263,9 @@ struct ip_conntrack_expect
/* Unique ID */
unsigned int id;
+ /* Flags */
+ unsigned int flags;
+
#ifdef CONFIG_IP_NF_NAT_NEEDED
/* This is the original per-proto part, used to map the
* expected connection the way the recipient expects. */
@@ -272,6 +275,8 @@ struct ip_conntrack_expect
#endif
};
+#define IP_CT_EXPECT_PERMANENT 0x1
+
static inline struct ip_conntrack *
tuplehash_to_ctrack(const struct ip_conntrack_tuple_hash *hash)
{
diff --git a/net/ipv4/netfilter/ip_conntrack_amanda.c b/net/ipv4/netfilter/ip_conntrack_amanda.c
index be4c9eb3243f..dc20881004bc 100644
--- a/net/ipv4/netfilter/ip_conntrack_amanda.c
+++ b/net/ipv4/netfilter/ip_conntrack_amanda.c
@@ -108,6 +108,7 @@ static int help(struct sk_buff **pskb,
}
exp->expectfn = NULL;
+ exp->flags = 0;
exp->tuple.src.ip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
exp->tuple.src.u.tcp.port = 0;
diff --git a/net/ipv4/netfilter/ip_conntrack_core.c b/net/ipv4/netfilter/ip_conntrack_core.c
index a0648600190e..e23e8ca476c0 100644
--- a/net/ipv4/netfilter/ip_conntrack_core.c
+++ b/net/ipv4/netfilter/ip_conntrack_core.c
@@ -264,10 +264,14 @@ find_expectation(const struct ip_conntrack_tuple *tuple)
master ct never got confirmed, we'd hold a reference to it
and weird things would happen to future packets). */
if (ip_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask)
- && is_confirmed(i->master)
- && del_timer(&i->timeout)) {
- unlink_expect(i);
- return i;
+ && is_confirmed(i->master)) {
+ if (i->flags & IP_CT_EXPECT_PERMANENT) {
+ atomic_inc(&i->use);
+ return i;
+ } else if (del_timer(&i->timeout)) {
+ unlink_expect(i);
+ return i;
+ }
}
}
return NULL;
diff --git a/net/ipv4/netfilter/ip_conntrack_ftp.c b/net/ipv4/netfilter/ip_conntrack_ftp.c
index 3a2627db1729..1b79ec36085f 100644
--- a/net/ipv4/netfilter/ip_conntrack_ftp.c
+++ b/net/ipv4/netfilter/ip_conntrack_ftp.c
@@ -421,6 +421,7 @@ static int help(struct sk_buff **pskb,
{ 0xFFFFFFFF, { .tcp = { 0xFFFF } }, 0xFF }});
exp->expectfn = NULL;
+ exp->flags = 0;
/* Now, NAT might want to mangle the packet, and register the
* (possibly changed) expectation itself. */
diff --git a/net/ipv4/netfilter/ip_conntrack_irc.c b/net/ipv4/netfilter/ip_conntrack_irc.c
index 25438eec21a1..d7a8a98c05e1 100644
--- a/net/ipv4/netfilter/ip_conntrack_irc.c
+++ b/net/ipv4/netfilter/ip_conntrack_irc.c
@@ -221,6 +221,7 @@ static int help(struct sk_buff **pskb,
{ { 0, { 0 } },
{ 0xFFFFFFFF, { .tcp = { 0xFFFF } }, 0xFF }});
exp->expectfn = NULL;
+ exp->flags = 0;
if (ip_nat_irc_hook)
ret = ip_nat_irc_hook(pskb, ctinfo,
addr_beg_p - ib_ptr,
diff --git a/net/ipv4/netfilter/ip_conntrack_netlink.c b/net/ipv4/netfilter/ip_conntrack_netlink.c
index a4e9278db4ed..3dc3a7bab3b4 100644
--- a/net/ipv4/netfilter/ip_conntrack_netlink.c
+++ b/net/ipv4/netfilter/ip_conntrack_netlink.c
@@ -1413,6 +1413,7 @@ ctnetlink_create_expect(struct nfattr *cda[])
}
exp->expectfn = NULL;
+ exp->flags = 0;
exp->master = ct;
memcpy(&exp->tuple, &tuple, sizeof(struct ip_conntrack_tuple));
memcpy(&exp->mask, &mask, sizeof(struct ip_conntrack_tuple));
diff --git a/net/ipv4/netfilter/ip_conntrack_tftp.c b/net/ipv4/netfilter/ip_conntrack_tftp.c
index f8ff170f390a..d2b590533452 100644
--- a/net/ipv4/netfilter/ip_conntrack_tftp.c
+++ b/net/ipv4/netfilter/ip_conntrack_tftp.c
@@ -75,6 +75,7 @@ static int tftp_help(struct sk_buff **pskb,
exp->mask.dst.u.udp.port = 0xffff;
exp->mask.dst.protonum = 0xff;
exp->expectfn = NULL;
+ exp->flags = 0;
DEBUGP("expect: ");
DUMP_TUPLE(&exp->tuple);
--
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