nf_ct_frag6_gather is part of nf_defrag_ipv6.ko, not ipv6 core.
The current use of the netfilter ipv6 stub indirections causes a module
dependency between ipv6 and nf_defrag_ipv6.
This prevents nf_defrag_ipv6 module from being removed because ipv6 can't
be unloaded.
Remove the indirection and always use a direct call. This creates a
depency from nf_conntrack_bridge to nf_defrag_ipv6 instead:
modinfo nf_conntrack
depends: nf_conntrack,nf_defrag_ipv6,bridge
.. and nf_conntrack already depends on nf_defrag_ipv6 anyway.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch removes the iph field from the state structure, which is not
properly initialized. Instead, add a new field to make the "do we want
to set DF" be the state bit and move the code to set the DF flag from
ip_frag_next().
Joint work with Pablo and Linus.
Fixes: 19c3401a91 ("net: ipv4: place control buffer handling away from fragmentation iterators")
Reported-by: Patrick Schönthaler <patrick@notvads.ovh>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Thomas found that some forwarded packets would be stuck
in FQ packet scheduler because their skb->tstamp contained
timestamps far in the future.
We thought we addressed this point in commit 8203e2d844
("net: clear skb->tstamp in forwarding paths") but there
is still an issue when/if a packet needs to be fragmented.
In order to meet EDT requirements, we have to make sure all
fragments get the original skb->tstamp.
Note that this original skb->tstamp should be zero in
forwarding path, but might have a non zero value in
output path if user decided so.
Fixes: fb420d5d91 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Thomas Bartschies <Thomas.Bartschies@cvk.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a struct definition function in nf_conntrack_bridge.h which is
not specific to conntrack and is used elswhere in netfilter. Move it
into netfilter_bridge.h.
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Include some headers in files which require them, and remove others
which are not required.
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
ip netns exec ns1 ip a a dev eth0 10.0.0.7/24
ip netns exec ns2 ip link a link eth0 name vlan type vlan id 200
ip netns exec ns2 ip a a dev vlan 10.0.0.8/24
ip l add dev br0 type bridge vlan_filtering 1
brctl addif br0 veth1
brctl addif br0 veth2
bridge vlan add dev veth1 vid 200 pvid untagged
bridge vlan add dev veth2 vid 200
A two fragment packet sent from ns2 contains the vlan tag 200. In the
bridge conntrack, this packet will defrag to one skb with fraglist.
When the packet is forwarded to ns1 through veth1, the first skb vlan
tag will be cleared by the "untagged" flags. But the vlan tag in the
second skb is still tagged, so the second fragment ends up with tag 200
to ns1. So if the first fragment packet doesn't contain the vlan tag,
all of the remain should not contain vlan tag.
Fixes: 3c171f496e ("netfilter: bridge: add connection tracking system")
Signed-off-by: wenxu <wenxu@ucloud.cn>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
br_defrag() and br_fragment() indirections are added in case that IPv6
support comes as a module, to avoid pulling innecessary dependencies in.
The new fraglist iterator and fragment transformer APIs are used to
implement the refragmentation code.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds basic connection tracking support for the bridge,
including initial IPv4 support.
This patch register two hooks to deal with the bridge forwarding path,
one from the bridge prerouting hook to call nf_conntrack_in(); and
another from the bridge postrouting hook to confirm the entry.
The conntrack bridge prerouting hook defragments packets before passing
them to nf_conntrack_in() to look up for an existing entry, otherwise a
new entry is allocated and it is attached to the skbuff. The conntrack
bridge postrouting hook confirms new conntrack entries, ie. if this is
the first packet seen, then it adds the entry to the hashtable and (if
needed) it refragments the skbuff into the original fragments, leaving
the geometry as is if possible. Exceptions are linearized skbuffs, eg.
skbuffs that are passed up to nfqueue and conntrack helpers, as well as
cloned skbuff for the local delivery (eg. tcpdump), also in case of
bridge port flooding (cloned skbuff too).
The packet defragmentation is done through the ip_defrag() call. This
forces us to save the bridge control buffer, reset the IP control buffer
area and then restore it after call. This function also bumps the IP
fragmentation statistics, it would be probably desiderable to have
independent statistics for the bridge defragmentation/refragmentation.
The maximum fragment length is stored in the control buffer and it is
used to refragment the skbuff from the postrouting path.
The new fraglist splitter and fragment transformer APIs are used to
implement the bridge refragmentation code. The br_ip_fragment() function
drops the packet in case the maximum fragment size seen is larger than
the output port MTU.
This patchset follows the principle that conntrack should not drop
packets, so users can do it through policy via invalid state matching.
Like br_netfilter, there is no refragmentation for packets that are
passed up for local delivery, ie. prerouting -> input path. There are
calls to nf_reset() already in several spots in the stack since time ago
already, eg. af_packet, that show that skbuff fraglist handling from the
netif_rx path is supported already.
The helpers are called from the postrouting hook, before confirmation,
from there we may see packet floods to bridge ports. Then, although
unlikely, this may result in exercising the helpers many times for each
clone. It would be good to explore how to pass all the packets in a list
to the conntrack hook to do this handle only once for this case.
Thanks to Florian Westphal for handing me over an initial patchset
version to add support for conntrack bridge.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
