From 2248bcfcd8fb622ec88b8587d0c1f139635ffd2e Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Tue, 6 Sep 2005 15:06:42 -0700 Subject: [NETFILTER]: Add support for permanent expectations A permanent expectation exists until timeing out and can expect multiple related connections. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- 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 088742b..7e033e9 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 be4c9eb..dc20881 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 a064860..e23e8ca 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 3a2627d..1b79ec3 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 25438ee..d7a8a98 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 a4e9278..3dc3a7b 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 f8ff170..d2b5905 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); -- cgit v1.1