since commit d6b915e29f
("ip_fragment: don't forward defragmented DF packet") the largest
fragment size is available in the IPCB.
Therefore we no longer need to care about 'encapsulation'
overhead of stripped PPPOE/VLAN headers since ip_do_fragment
doesn't use device mtu in such cases.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Might not have an outdev yet. We'll oops when iface goes down while skbs
are still nfqueue'd:
RIP: 0010:[<ffffffff81422a2f>] [<ffffffff81422a2f>] dev_cmp+0x4f/0x80
nfqnl_rcv_dev_event+0xe2/0x150
notifier_call_chain+0x53/0xa0
Fixes: c737b7c451 ("netfilter: bridge: add helpers for fetching physin/outdev")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_bridge_info->mask is used for several things, for example to
remember if skb->pkt_type was set to OTHER_HOST.
For a bridge, OTHER_HOST is expected case. For ip forward its a non-starter
though -- routing expects PACKET_HOST.
Bridge netfilter thus changes OTHER_HOST to PACKET_HOST before hook
invocation and then un-does it after hook traversal.
This information is irrelevant outside of br_netfilter.
After this change, ->mask now only contains flags that need to be
known outside of br_netfilter in fast-path.
Future patch changes mask into a 2bit state field in sk_buff, so that
we can remove skb->nf_bridge pointer for good and consider all remaining
places that access nf_bridge info content a not-so fastpath.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
->mask is a bit info field that mixes various use cases.
In particular, we have flags that are mutually exlusive, and flags that
are only used within br_netfilter while others need to be exposed to
other parts of the kernel.
Remove BRNF_8021Q/PPPoE flags. They're mutually exclusive and only
needed within br_netfilter context.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
right now we store this in the nf_bridge_info struct, accessible
via skb->nf_bridge. This patch prepares removal of this pointer from skb:
Instead of using skb->nf_bridge->x, we use helpers to obtain the in/out
device (or ifindexes).
Followup patches to netfilter will then allow nf_bridge_info to be
obtained by a call into the br_netfilter core, rather than keeping a
pointer to it in sk_buff.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
On the output paths in particular, we have to sometimes deal with two
socket contexts. First, and usually skb->sk, is the local socket that
generated the frame.
And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.
We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.
The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device. We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.
Signed-off-by: David S. Miller <davem@davemloft.net>
The br_netfilter frag output function calls skb_cow_head() so in
case it needs a larger headroom to e.g. re-add a previously stripped PPPOE
or VLAN header things will still work (at cost of reallocation).
We can then move nf_bridge_encap_header_len to br_netfilter.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Its not needed anymore since 2bf540b73e
([NETFILTER]: bridge-netfilter: remove deferred hooks).
Before this it was possible to have physoutdev set for locally generated
packets -- this isn't the case anymore:
BRNF_STATE_BRIDGED flag is set when we assign nf_bridge->physoutdev,
so physoutdev != NULL means BRNF_STATE_BRIDGED is set.
If physoutdev is NULL, then we are looking at locally-delivered and
routed packet.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
ask conntrack instead of storing ipv4 address in nf_bridge_info->data.
Ths avoids the need to use ->data during NF_PRE_ROUTING.
Only two functions that need ->data remain.
These will be addressed in followup patches.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Only one caller, there is no need to keep this in a header.
Move it to br_netfilter.c where this belongs to.
Based on patch from Florian Westphal.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The mac header only has to be copied back into the skb for
fragments generated by ip_fragment(), which only happens
for bridge forwarded packets with nf-call-iptables=1 && active nf_defrag.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Jesper reported that br_netfilter always registers the hooks since
this is part of the bridge core. This harms performance for people that
don't need this.
This patch modularizes br_netfilter so it can be rmmod'ed, thus,
the hooks can be unregistered. I think the bridge netfilter should have
been a separated module since the beginning, Patrick agreed on that.
Note that this is breaking compatibility for users that expect that
bridge netfilter is going to be available after explicitly 'modprobe
bridge' or via automatic load through brctl.
However, the damage can be easily undone by modprobing br_netfilter.
The bridge core also spots a message to provide a clue to people that
didn't notice that this has been deprecated.
On top of that, the plan is that nftables will not rely on this software
layer, but integrate the connection tracking into the bridge layer to
enable stateful filtering and NAT, which is was bridge netfilter users
seem to require.
This patch still keeps the fake_dst_ops in the bridge core, since this
is required by when the bridge port is initialized. So we can safely
modprobe/rmmod br_netfilter anytime.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Florian Westphal <fw@strlen.de>
Move nf_bridge_copy_header() as static inline in netfilter_bridge.h
header file. This patch prepares the modularization of the br_netfilter
code.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are a mix of function prototypes with and without extern
in the kernel sources. Standardize on not using extern for
function prototypes.
Function prototypes don't need to be written with extern.
extern is assumed by the compiler. Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
bridge: set fake_rtable's dst to NULL to avoid kernel Oops
when bridge is deleted before tap/vif device's delete, kernel may
encounter an oops because of NULL reference to fake_rtable's dst.
Set fake_rtable's dst to NULL before sending packets out can solve
this problem.
v4 reformat, change br_drop_fake_rtable(skb) to {}
v3 enrich commit header
v2 introducing new flag DST_FAKE_RTABLE to dst_entry struct.
[ Use "do { } while (0)" for nop br_drop_fake_rtable()
implementation -DaveM ]
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Peter Huang <peter.huangpeng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The MTU for IP traffic encapsulated inside PPPoE traffic is smaller
than the MTU of the Ethernet device (1500). Connection tracking
gathers all IP packets and sometimes will refragment them in
ip_fragment(). We then need to subtract the length of the
encapsulating header from the mtu used in ip_fragment(). The check in
br_nf_dev_queue_xmit() which determines if ip_fragment() has to be
called is also updated for the PPPoE-encapsulated packets.
nf_bridge_copy_header() is also updated to make sure the PPPoE data
length field has the correct value.
Signed-off-by: Bart De Schuymer <bdschuym@pandora.be>
Signed-off-by: Patrick McHardy <kaber@trash.net>
- fix IP DNAT on vlan- or pppoe-encapsulated traffic: The functions
neigh_hh_output() or dst->neighbour->output() overwrite the complete
Ethernet header, although we only need the destination MAC address.
For encapsulated packets, they ended up overwriting the encapsulating
header. The new code copies the Ethernet source MAC address and
protocol number before calling dst->neighbour->output(). The Ethernet
source MAC and protocol number are copied back in place in
br_nf_pre_routing_finish_bridge_slow(). This also makes the IP DNAT
more transparent because in the old scheme the source MAC of the
bridge was copied into the source address in the Ethernet header. We
also let skb->protocol equal ETH_P_IP resp. ETH_P_IPV6 during the
execution of the PF_INET resp. PF_INET6 hooks.
- Speed up IP DNAT by calling neigh_hh_bridge() instead of
neigh_hh_output(): if dst->hh is available, we already know the MAC
address so we can just copy it.
Signed-off-by: Bart De Schuymer <bdschuym@pandora.be>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Remove br_netfilter.c::br_nf_local_out(). The function
br_nf_local_out() was needed because the PF_BRIDGE::LOCAL_OUT hook
could be called when IP DNAT happens on to-be-bridged traffic. The
new scheme eliminates this mess.
Signed-off-by: Bart De Schuymer <bdschuym@pandora.be>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Base versions handle constant folding now. For headers exposed to
userspace, we must only expose the __ prefixed versions.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Damien Thebault, the double POSTROUTING hook invocation
fix caused outgoing packets routed between two bridges to appear without
a link-layer header. The reason for this is that we're skipping the
br_nf_post_routing hook for routed packets now and don't save the
original link layer header, but nevertheless tries to restore it on
output, causing corruption.
The root cause for this is that skb->nf_bridge has no clearly defined
lifetime and is used to indicate all kind of things, but that is
quite complicated to fix. For now simply don't touch these packets
and handle them like packets from any other device.
Tested-by: Damien Thebault <damien.thebault@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Consolidate the common push/pull sequences into a few helper functions.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The attached patch by Michael Milner adds support for using iptables and
ip6tables on bridged traffic encapsulated in ppoe frames, similar to
what's already supported for vlan.
Signed-off-by: Michael Milner <milner@blissisland.ca>
Signed-off-by: Bart De Schuymer <bdschuym@pandora.be>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the deferred hooks and all related code as scheduled in
feature-removal-schedule.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do some simple optimization on the nf_bridge_pad() function
and don't use magic constants. Eliminate a double call and
the #ifdef'd code for CONFIG_BRIDGE_NETFILTER.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cleanup and rearrangement for better style and clarity:
Split the function nf_bridge_maybe_copy_header into two pieces
Move copy portion out of line.
Use Ethernet header size macros.
Use header file to handle CONFIG_NETFILTER_BRIDGE differences
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bridge-netfilter code will overwrite memory if there is not
headroom in the skb to save the header. This first showed up when
using Xen with sky2 driver that doesn't allocate the extra space.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Header doesn't use anything from atomic.h.
It fixes headers_check warning:
include/linux/netfilter_bridge.h requires asm/atomic.h, which does not exist
Compile tested on
alpha arm i386-up sparc sparc64-up x86_64
alpha-up i386 sparc64 sparc-up x86_64-up
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add bridge netfilter deferred output hooks to feature-removal-schedule
and disable them by default. Until their removal they will be
activated by the physdev match when needed.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move nf_bridge_alloc from header file to the one place it is
used and optimize it.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Florian Westphal