This patch adds the basic infrastructure to support user-space
expectation helpers via ctnetlink and the netfilter queuing
infrastructure NFQUEUE. Basically, this patch:
* adds NF_CT_EXPECT_USERSPACE flag to identify user-space
created expectations. I have also added a sanity check in
__nf_ct_expect_check() to avoid that kernel-space helpers
may create an expectation if the master conntrack has no
helper assigned.
* adds some branches to check if the master conntrack helper
exists, otherwise we skip the code that refers to kernel-space
helper such as the local expectation list and the expectation
policy.
* allows to set the timeout for user-space expectations with
no helper assigned.
* a list of expectations created from user-space that depends
on ctnetlink (if this module is removed, they are deleted).
* includes USERSPACE in the /proc output for expectations
that have been created by a user-space helper.
This patch also modifies ctnetlink to skip including the helper
name in the Netlink messages if no kernel-space helper is set
(since no user-space expectation has not kernel-space kernel
assigned).
You can access an example user-space FTP conntrack helper at:
http://people.netfilter.org/pablo/userspace-conntrack-helpers/nf-ftp-helper-userspace-POC.tar.bz
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
With this patch, you can specify the expectation flags for user-space
created expectations.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch adds the missing validation of the CTA_EXPECT_ZONE
attribute in the ctnetlink code.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Change the usage of svc usecnt during command execution:
- we check if svc is registered but we do not need to hold usecnt
reference while under __ip_vs_mutex, only the packet handling needs
it during scheduling
- change __ip_vs_service_get to __ip_vs_service_find and
__ip_vs_svc_fwm_get to __ip_vs_svc_fwm_find because now caller
will increase svc->usecnt
- put common code that calls update_service in __ip_vs_update_dest
- put common code in ip_vs_unlink_service() and use it to unregister
the service
- add comment that svc should not be accessed after ip_vs_del_service
anymore
- all IP_VS_WAIT_WHILE calls are now unified: usecnt > 0
- Properly log the app ports
As result, some problems are fixed:
- possible use-after-free of svc in ip_vs_genl_set_cmd after
ip_vs_del_service because our usecnt reference does not guarantee that
svc is not freed on refcnt==0, eg. when no dests are moved to trash
- possible usecnt leak in do_ip_vs_set_ctl after ip_vs_del_service
when the service is not freed now, for example, when some
destionations are moved into trash and svc->refcnt remains above 0.
It is harmless because svc is not in hash anymore.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Since we don't change the tuple in the original direction, we can save it
in ct->tuplehash[IP_CT_DIR_REPLY].hnode.pprev for __nf_conntrack_confirm()
use.
__hash_conntrack() is split into two steps: hash_conntrack_raw() is used
to get the raw hash, and __hash_bucket() is used to get the bucket id.
In SYN-flood case, early_drop() doesn't need to recompute the hash again.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Add new sysctl flag "snat_reroute". Recent kernels use
ip_route_me_harder() to route LVS-NAT responses properly by
VIP when there are multiple paths to client. But setups
that do not have alternative default routes can skip this
routing lookup by using snat_reroute=0.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Add more code to IPVS to work with Netfilter connection
tracking and fix some problems.
- Allow IPVS to be compiled without connection tracking as in
2.6.35 and before. This can avoid keeping conntracks for all
IPVS connections because this costs memory. ip_vs_ftp still
depends on connection tracking and NAT as implemented for 2.6.36.
- Add sysctl var "conntrack" to enable connection tracking for
all IPVS connections. For loaded IPVS directors it needs
tuning of nf_conntrack_max limit.
- Add IP_VS_CONN_F_NFCT connection flag to request the connection
to use connection tracking. This allows user space to provide this
flag, for example, in dest->conn_flags. This can be useful to
request connection tracking per real server instead of forcing it
for all connections with the "conntrack" sysctl. This flag is
set currently only by ip_vs_ftp and of course by "conntrack" sysctl.
- Add ip_vs_nfct.c file to hold all connection tracking code,
by this way main code should not depend of netfilter conntrack
support.
- Return back the ip_vs_post_routing handler as in 2.6.35 and use
skb->ipvs_property=1 to allow IPVS to work without connection
tracking
Connection tracking:
- most of the code is already in 2.6.36-rc
- alter conntrack reply tuple for LVS-NAT connections when first packet
from client is forwarded and conntrack state is NEW or RELATED.
Additionally, alter reply for RELATED connections from real server,
again for packet in original direction.
- add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering
reply) for LVS-TUN early because we want to call nf_reset. It is
needed because we add IPIP header and the original conntrack
should be preserved, not destroyed. The transmitted IPIP packets
can reuse same conntrack, so we do not set skb->ipvs_property.
- try to destroy conntrack when the IPVS connection is destroyed.
It is not fatal if conntrack disappears before that, it depends
on the used timers.
Fix problems from long time:
- add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Patrick McHardy <kaber@trash.net>
- the sync protocol supports 16 bits only, so bits 0..15 should be
used only for flags that should go to backup server, bits 16 and
above should be allocated for flags not sent to backup.
- use IP_VS_CONN_F_DEST_MASK as mask of connection flags in
destination that can be changed by user space
- allow IP_VS_CONN_F_ONE_PACKET to be set in destination
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Patrick McHardy <kaber@trash.net>
nf_conntrack_alloc() isn't called with nf_conntrack_lock locked, so hash
random initializing code maybe executed more than once on different
CPUs.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
The field family of xt_target should be NFPROTO_IPV4, though
NFPROTO_IPV4 and AF_INET are the same.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
- Do not create expectation when forwarding the PORT
command to avoid blocking the connection. The problem is that
nf_conntrack_ftp.c:help() tries to create the same expectation later in
POST_ROUTING and drops the packet with "dropping packet" message after
failure in nf_ct_expect_related.
- Change ip_vs_update_conntrack to alter the conntrack
for related connections from real server. If we do not alter the reply in
this direction the next packet from client sent to vport 20 comes as NEW
connection. We alter it but may be some collision happens for both
conntracks and the second conntrack gets destroyed immediately. The
connection stucks too.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix Passive FTP problem in ip_vs_ftp:
- Do not oops in nf_nat_set_seq_adjust (adjust_tcp_sequence) when
iptable_nat module is not loaded
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use correctly the in_pkts packet counter also for SCTP
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes this build error:
net/netfilter/ipvs/ip_vs_core.c: In function 'ip_vs_nat_icmp_v6':
net/netfilter/ipvs/ip_vs_core.c:640: error: implicit declaration of function 'csum_ipv6_magic'
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Switch from GFP_ATOMIC allocations to GFP_KERNEL ones in
ip_vs_add_service() and ip_vs_new_dest(), as we hold a mutex and are
allowed to sleep in this context.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also rename __ip_vs_securetcp_lock to ip_vs_securetcp_lock.
Spinlock conversion was suggested by Eric Dumazet.
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also rename __ip_vs_sched_lock to ip_vs_sched_lock.
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Xiaoyu Du <tingsrain@gmail.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
__ip_vs_service_get and __ip_vs_svc_fwm_get increment a reference count, so
that reference count should be decremented before leaving the function in an
error case.
A simplified version of the semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)
// <smpl>
@r exists@
local idexpression x;
expression E;
identifier f1;
iterator I;
@@
x = __ip_vs_service_get(...);
<... when != x
when != true (x == NULL || ...)
when != if (...) { <+...x...+> }
when != I (...) { <+...x...+> }
(
x == NULL
|
x == E
|
x->f1
)
...>
* return ...;
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
use skb->len for accounting as xt_quota does. Since nf_conntrack works
at the network layer, skb_network_offset should always returns ZERO.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This removes duplicate code by providing a default implementation
which is used by 3 of the 4 modules that provide these call.
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
IPVS was merged into the kernel quite a long time ago and
has been seeing wide-spread production use for even longer.
It seems appropriate for it to be no longer tagged as EXPERIMENTAL
Signed-off-as: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
some users of nf_ct_ext_exist() know ct->ext isn't NULL. For these users, the
check for ct->ext isn't necessary, the function __nf_ct_ext_exist() can be
used instead.
the type of the return value of nf_ct_ext_exist() is changed to bool.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
We should copy the initial value to userspace for iptables-save and
to allow removal of specific quota rules.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
In some situations a CPU match permits a better spreading of
connections, or select targets only for a given cpu.
With Remote Packet Steering or multiqueue NIC and appropriate IRQ
affinities, we can distribute trafic on available cpus, per session.
(all RX packets for a given flow is handled by a given cpu)
Some legacy applications being not SMP friendly, one way to scale a
server is to run multiple copies of them.
Instead of randomly choosing an instance, we can use the cpu number as a
key so that softirq handler for a whole instance is running on a single
cpu, maximizing cache effects in TCP/UDP stacks.
Using NAT for example, a four ways machine might run four copies of
server application, using a separate listening port for each instance,
but still presenting an unique external port :
iptables -t nat -A PREROUTING -p tcp --dport 80 -m cpu --cpu 0 \
-j REDIRECT --to-port 8080
iptables -t nat -A PREROUTING -p tcp --dport 80 -m cpu --cpu 1 \
-j REDIRECT --to-port 8081
iptables -t nat -A PREROUTING -p tcp --dport 80 -m cpu --cpu 2 \
-j REDIRECT --to-port 8082
iptables -t nat -A PREROUTING -p tcp --dport 80 -m cpu --cpu 3 \
-j REDIRECT --to-port 8083
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Use nf_conntrack/nf_nat code to do the packet mangling and the TCP
sequence adjusting. The function 'ip_vs_skb_replace' is now dead
code, so it is removed.
To SNAT FTP, use something like:
% iptables -t nat -A POSTROUTING -m ipvs --vaddr 192.168.100.30/32 \
--vport 21 -j SNAT --to-source 192.168.10.10
and for the data connections in passive mode:
% iptables -t nat -A POSTROUTING -m ipvs --vaddr 192.168.100.30/32 \
--vportctl 21 -j SNAT --to-source 192.168.10.10
using '-m state --state RELATED' would also works.
Make sure the kernel modules ip_vs_ftp, nf_conntrack_ftp, and
nf_nat_ftp are loaded.
[ up-port and minor fixes by Simon Horman <horms@verge.net.au> ]
Signed-off-by: Hannes Eder <heder@google.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Update the nf_conntrack tuple in reply direction, as we will see
traffic from the real server (RIP) to the client (CIP). Once this is
done we can use netfilters SNAT in POSTROUTING, especially with
xt_ipvs, to do source NAT, e.g.:
% iptables -t nat -A POSTROUTING -m ipvs --vaddr 192.168.100.30/32 --vport 80 \
-j SNAT --to-source 192.168.10.10
[ minor fixes by Simon Horman <horms@verge.net.au> ]
Signed-off-by: Hannes Eder <heder@google.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This implements the kernel-space side of the netfilter matcher xt_ipvs.
[ minor fixes by Simon Horman <horms@verge.net.au> ]
Signed-off-by: Hannes Eder <heder@google.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
[ Patrick: added xt_ipvs.h to Kbuild ]
Signed-off-by: Patrick McHardy <kaber@trash.net>
This adds a `CHECKSUM' target, which can be used in the iptables mangle
table.
You can use this target to compute and fill in the checksum in
a packet that lacks a checksum. This is particularly useful,
if you need to work around old applications such as dhcp clients,
that do not work well with checksum offloads, but don't want to
disable checksum offload in your device.
The problem happens in the field with virtualized applications.
For reference, see Red Hat bz 605555, as well as
http://www.spinics.net/lists/kvm/msg37660.html
Typical expected use (helps old dhclient binary running in a VM):
iptables -A POSTROUTING -t mangle -p udp --dport bootpc \
-j CHECKSUM --checksum-fill
Includes fixes by Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch adds the missing bits to support the recovery of TCP flows
without disabling window tracking (aka be_liberal). To ensure a
successful recovery, we have to inject the window scale factor via
ctnetlink.
This patch has been tested with a development snapshot of conntrackd
and the new clause `TCPWindowTracking' that allows to perform strict
TCP window tracking recovery across fail-overs.
With this patch, we don't update the receiver's window until it's not
initiated. We require this to perform a successful recovery. Jozsef
confirmed in a private email that this spotted a real issue since that
should not happen.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
According to the Documentation/CodingStyle, the length of lines should
be within 80.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
lvs sctp protocol handler is incorrectly invoked ip_vs_app_pkt_out
Since there's no sctp helpers at present, it does the same thing as
ip_vs_app_pkt_in.
Signed-off-by: Xiaoyu Du <tingsrain@gmail.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
IP_VS_PROTO_AH_ESP should be set iff either of IP_VS_PROTO_{AH,ESP} is
selected. Express this with standard kconfig syntax.
Signed-off-by: Michal Marek <mmarek@suse.cz>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
CONFIG_NF_CT_ACCT has been deprecated for awhile and
was originally scheduled for removal by 2.6.29.
Removing support for this config option also stops
this deprecation warning message in the kernel log.
[ 61.669627] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
[ 61.669850] CONFIG_NF_CT_ACCT is deprecated and will be removed soon. Please use
[ 61.669852] nf_conntrack.acct=1 kernel parameter, acct=1 nf_conntrack module option or
[ 61.669853] sysctl net.netfilter.nf_conntrack_acct=1 to enable it.
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
[Patrick: changed default value to 0]
Signed-off-by: Patrick McHardy <kaber@trash.net>
Check at rule install time that CT accounting is enabled. Force it
to be enabled if not while also emitting a warning since this is not
the default state.
This is in preparation for deprecating CONFIG_NF_CT_ACCT upon which
CONFIG_NETFILTER_XT_MATCH_CONNBYTES depended being set.
Added 2 CT accounting support functions:
nf_ct_acct_enabled() - Get CT accounting state.
nf_ct_set_acct() - Enable/disable CT accountuing.
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Destination was spelled wrong in KConfig.
Signed-off-by: Arnd Hannemann <hannemann@nets.rwth-aachen.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Add header file to fix build error:
net/netfilter/xt_IDLETIMER.c:276: error: implicit declaration of function 'MKDEV'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Allow one-packet scheduling for UDP connections. When the fwmark-based or
normal virtual service is marked with '-o' or '--ops' options all
connections are created only to schedule one packet. Useful to schedule UDP
packets from same client port to different real servers. Recommended with
RR or WRR schedulers (the connections are not visible with ipvsadm -L).
Signed-off-by: Nick Chalk <nick@loadbalancer.org>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Register net_bridge_port pointer as rx_handler data pointer. As br_port is
removed from struct net_device, another netdev priv_flag is added to indicate
the device serves as a bridge port. Also rcuized pointers are now correctly
dereferenced in br_fdb.c and in netfilter parts.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>