netfilter: xt_mangle: only check verdict part of return value

These checks assume that the caller only returns NF_DROP without
any errno embedded in the upper bits.

This is fine right now, but followup patches will start to propagate
such errors to allow kfree_skb_drop_reason() in the called functions,
those would then indicate 'errno << 8 | NF_STOLEN'.

To not break things we have to mask those parts out.

Signed-off-by: Florian Westphal <fw@strlen.de>

netfilter: iptables: allow use of ipt_do_table as hookfn

This is possible now that the xt_table structure is passed in via *priv.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: x_tables: handle xt_register_template() returning an error value

Commit fdacd57c79b7 ("netfilter: x_tables: never register tables by
default") introduces the function xt_register_template(), and in one case,
a call to that function was missing the error-case handling.

Handle when xt_register_template() returns an error value.

This was identified with the clang-analyzer's Dead-Store analysis.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: x_tables: never register tables by default

For historical reasons x_tables still register tables by default in the
initial namespace.
Only newly created net namespaces add the hook on demand.

This means that the init_net always pays hook cost, even if no filtering
rules are added (e.g. only used inside a single netns).

Note that the hooks are added even when 'iptables -L' is called.
This is because there is no way to tell 'iptables -A' and 'iptables -L'
apart at kernel level.

The only solution would be to register the table, but delay hook
registration until the first rule gets added (or policy gets changed).

That however means that counters are not hooked either, so 'iptables -L'
would always show 0-counters even when traffic is flowing which might be
unexpected.

This keeps table and hook registration consistent with what is already done
in non-init netns: first iptables(-save) invocation registers both table
and hooks.

This applies the same solution adopted for ebtables.
All tables register a template that contains the l3 family, the name
and a constructor function that is called when the initial table has to
be added.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: ip_tables: pass table pointer via nf_hook_ops

iptable_x modules rely on 'struct net' to contain a pointer to the
table that should be evaluated.

In order to remove these pointers from struct net, pass them via
the 'priv' pointer in a similar fashion as nf_tables passes the
rule data.

To do that, duplicate the nf_hook_info array passed in from the
iptable_x modules, update the ops->priv pointers of the copy to
refer to the table and then change the hookfn implementations to
just pass the 'priv' argument to the traverser.

After this patch, the xt_table pointers can already be removed
from struct net.

However, changes to struct net result in re-compile of the entire
network stack, so do the removal after arptables and ip6tables
have been converted as well.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: x_tables: remove paranoia tests

No need for these.
There is only one caller, the xtables core, when the table is registered
for the first time with a particular network namespace.

After ->table_init() call, the table is linked into the tables[af] list,
so next call to that function will skip the ->table_init().

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: iptables: unregister the tables by name

xtables stores the xt_table structs in the struct net. This isn't
needed anymore, the structures could be passed via the netfilter hook
'private' pointer to the hook functions, which would allow us to remove
those pointers from struct net.

As a first step, reduce the number of accesses to the
net->ipv4.ip6table_{raw,filter,...} pointers.
This allows the tables to get unregistered by name instead of having to
pass the raw address.

The xt_table structure cane looked up by name+address family instead.

This patch is useless as-is (the backends still have the raw pointer
address), but it lowers the bar to remove those.

It also allows to put the 'was table registered in the first place' check
into ip_tables.c rather than have it in each table sub module.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: use actual socket sk rather than skb sk when routing harder

If netfilter changes the packet mark when mangling, the packet is
rerouted using the route_me_harder set of functions. Prior to this
commit, there's one big difference between route_me_harder and the
ordinary initial routing functions, described in the comment above
__ip_queue_xmit():

/* Note: skb->sk can be different from sk, in case of tunnels */
int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,

That function goes on to correctly make use of sk->sk_bound_dev_if,
rather than skb->sk->sk_bound_dev_if. And indeed the comment is true: a
tunnel will receive a packet in ndo_start_xmit with an initial skb->sk.
It will make some transformations to that packet, and then it will send
the encapsulated packet out of a *new* socket. That new socket will
basically always have a different sk_bound_dev_if (otherwise there'd be
a routing loop). So for the purposes of routing the encapsulated packet,
the routing information as it pertains to the socket should come from
that socket's sk, rather than the packet's original skb->sk. For that
reason __ip_queue_xmit() and related functions all do the right thing.

One might argue that all tunnels should just call skb_orphan(skb) before
transmitting the encapsulated packet into the new socket. But tunnels do
*not* do this -- and this is wisely avoided in skb_scrub_packet() too --
because features like TSQ rely on skb->destructor() being called when
that buffer space is truely available again. Calling skb_orphan(skb) too
early would result in buffers filling up unnecessarily and accounting
info being all wrong. Instead, additional routing must take into account
the new sk, just as __ip_queue_xmit() notes.

So, this commit addresses the problem by fishing the correct sk out of
state->sk -- it's already set properly in the call to nf_hook() in
__ip_local_out(), which receives the sk as part of its normal
functionality. So we make sure to plumb state->sk through the various
route_me_harder functions, and then make correct use of it following the
example of __ip_queue_xmit().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: iptables: Add a .pre_exit hook in all iptable_foo.c.

Using new helpers ipt_unregister_table_pre_exit() and
ipt_unregister_table_exit().

Fixes: b9e69e127397 ("netfilter: xtables: don't hook tables by default")
Signed-off-by: David Wilder <dwilder@us.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: Drop pernet_operations::async

Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Convert iptable_mangle_net_ops

These pernet_operations unregister net::ipv4::iptable_mangle table.
Another net/pernet_operations do not send ipv4 packets to foreign
net namespaces. So, we mark them async.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: remove defensive check on malformed packets from raw sockets

Users cannot forge malformed IPv4/IPv6 headers via raw sockets that they
can inject into the stack. Specifically, not for IPv4 since 55888dfb6ba7
("AF_RAW: Augment raw_send_hdrinc to expand skb to fit iphdr->ihl
(v2)"). IPv6 raw sockets also ensure that packets have a well-formed
IPv6 header available in the skbuff.

At quick glance, br_netfilter also validates layer 3 headers and it
drops malformed both IPv4 and IPv6 packets.

Therefore, let's remove this defensive check all over the place.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: x_tables: simplify ip{6}table_mangle_hook()

No need for a special case to handle NF_INET_POST_ROUTING, this is
basically the same handling as for prerouting, input, forward.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: xtables: don't hook tables by default

delay hook registration until the table is being requested inside a
namespace.

Historically, a particular table (iptables mangle, ip6tables filter, etc)
was registered on module load.

When netns support was added to iptables only the ip/ip6tables ruleset was
made namespace aware, not the actual hook points.

This means f.e. that when ipt_filter table/module is loaded on a system,
then each namespace on that system has an (empty) iptables filter ruleset.

In other words, if a namespace sends a packet, such skb is 'caught' by
netfilter machinery and fed to hooking points for that table (i.e. INPUT,
FORWARD, etc).

Thanks to Eric Biederman, hooks are no longer global, but per namespace.

This means that we can avoid allocation of empty ruleset in a namespace and
defer hook registration until we need the functionality.

We register a tables hook entry points ONLY in the initial namespace.
When an iptables get/setockopt is issued inside a given namespace, we check
if the table is found in the per-namespace list.

If not, we attempt to find it in the initial namespace, and, if found,
create an empty default table in the requesting namespace and register the
needed hooks.

Hook points are destroyed only once namespace is deleted, there is no
'usage count' (it makes no sense since there is no 'remove table' operation
in xtables api).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: xtables: prepare for on-demand hook register

This change prepares for upcoming on-demand xtables hook registration.

We change the protoypes of the register/unregister functions.
A followup patch will then add nf_hook_register/unregister calls
to the iptables one.

Once a hook is registered packets will be picked up, so all assignments
of the form

net->ipv4.iptable_$table = new_table

have to be moved to ip(6)t_register_table, else we can see NULL
net->ipv4.iptable_$table later.

This patch doesn't change functionality; without this the actual change
simply gets too big.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

ipv4: Pass struct net into ip_route_me_harder

Don't make ip_route_me_harder guess which network namespace
it is routing in, pass the network namespace in.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: Pass priv instead of nf_hook_ops to netfilter hooks

Only pass the void *priv parameter out of the nf_hook_ops. That is
all any of the functions are interested now, and by limiting what is
passed it becomes simpler to change implementation details.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

inet netfilter: Remove hook from ip6t_do_table, arp_do_table, ipt_do_table

The values of ops->hooknum and state->hook are guaraneted to be equal
making the hook argument to ip6t_do_table, arp_do_table, and
ipt_do_table is unnecessary. Remove the unnecessary hook argument.

In the callers use state->hook instead of ops->hooknum for clarity and
to reduce the number of cachelines the callers touch.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: Use nf_hook_state.net

Instead of saying "net = dev_net(state->in?state->in:state->out)"
just say "state->net". As that information is now availabe,
much less confusing and much less error prone.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: Pass nf_hook_state through ipt_do_table().

Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: Make nf_hookfn use nf_hook_state.

Pass the nf_hook_state all the way down into the hook
functions themselves.

Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: pass hook ops to hookfn

Pass the hook ops to the hookfn to allow for generic hook
functions. This change is required by nf_tables.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

PTR_RET is now PTR_ERR_OR_ZERO(): Replace most.

Sweep of the simple cases.

Cc: netdev@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

netfilter: ipv4: propagate routing errors from ip_route_me_harder()

Propagate routing errors from ip_route_me_harder() when dropping a packet
using NF_DROP_ERR(). This makes userspace get the proper error instead of
EPERM for everything.

Example:

# ip r a unreachable default table 100
# ip ru add fwmark 0x1 lookup 100
# iptables -t mangle -A OUTPUT -d 8.8.8.8 -j MARK --set-mark 0x1

Current behaviour:

PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted

New behaviour:

PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
ping: sendmsg: Network is unreachable
ping: sendmsg: Network is unreachable
ping: sendmsg: Network is unreachable
ping: sendmsg: Network is unreachable

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: remove unnecessary goto statement for error recovery

Usually it's a good practice to use goto statement for error recovery
when initializing the module. This approach could be an overkill if:

1) there is only one fail case;
2) success and failure use the same return statement.

For a cleaner approach, remove the unnecessary goto statement and
directly implement error recovery.

Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: PTR_RET can be used

This quiets the coccinelle warnings:

net/bridge/netfilter/ebtable_filter.c:107:1-3: WARNING: PTR_RET can be used
net/bridge/netfilter/ebtable_nat.c:107:1-3: WARNING: PTR_RET can be used
net/ipv6/netfilter/ip6table_filter.c:65:1-3: WARNING: PTR_RET can be used
net/ipv6/netfilter/ip6table_mangle.c:100:1-3: WARNING: PTR_RET can be used
net/ipv6/netfilter/ip6table_raw.c:44:1-3: WARNING: PTR_RET can be used
net/ipv6/netfilter/ip6table_security.c:62:1-3: WARNING: PTR_RET can be used
net/ipv4/netfilter/iptable_filter.c:72:1-3: WARNING: PTR_RET can be used
net/ipv4/netfilter/iptable_mangle.c:107:1-3: WARNING: PTR_RET can be used
net/ipv4/netfilter/iptable_raw.c:51:1-3: WARNING: PTR_RET can be used
net/ipv4/netfilter/iptable_security.c:70:1-3: WARNING: PTR_RET can be used

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: do not omit re-route check on NF_QUEUE verdict

ret != NF_QUEUE only works in the "--queue-num 0" case; for
queues > 0 the test should be '(ret & NF_VERDICT_MASK) != NF_QUEUE'.

However, NF_QUEUE no longer DROPs the skb unconditionally if queueing
fails (due to NF_VERDICT_FLAG_QUEUE_BYPASS verdict flag), so the
re-route test should also be performed if this flag is set in the
verdict.

The full test would then look something like

&& ((ret & NF_VERDICT_MASK) == NF_QUEUE && (ret & NF_VERDICT_FLAG_QUEUE_BYPASS))

This is rather ugly, so just remove the NF_QUEUE test altogether.

The only effect is that we might perform an unnecessary route lookup
in the NF_QUEUE case.

ip6table_mangle did not have such a check.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

netfilter: iptables: remove unused function arguments

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

netfilter: xtables: fix mangle tables

In POST_ROUTING hook, calling dev_net(in) is going to oops.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: xtables: generate initial table on-demand

The static initial tables are pretty large, and after the net
namespace has been instantiated, they just hang around for nothing.
This commit removes them and creates tables on-demand at runtime when
needed.

Size shrinks by 7735 bytes (x86_64).

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

netfilter: xtables: use xt_table for hook instantiation

The respective xt_table structures already have most of the metadata
needed for hook setup. Add a 'priority' field to struct xt_table so
that xt_hook_link() can be called with a reduced number of arguments.

So should we be having more tables in the future, it comes at no
static cost (only runtime, as before) - space saved:
6807373->6806555.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

netfilter: xtables: compact table hook functions (1/2)

This patch combines all the per-hook functions in a given table into
a single function. Together with the 2nd patch, further
simplifications are possible up to the point of output code reduction.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

netfilter: xtables: add struct xt_mtdtor_param::net

Add ->net to match destructor list like ->net in constructor list.

Make sure it's set in ebtables/iptables/ip6tables, this requires to
propagate netns up to *_unregister_table().

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: net/ipv[46]/netfilter: Move && and || to end of previous line

Compile tested only.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: xtables: mark initial tables constant

The inputted table is never modified, so should be considered const.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: xtables: switch table AFs to nfproto

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

netfilter: xtables: switch hook PFs to nfproto

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

netfilter: x_tables: remove unneeded initializations

Later patches change the locking on xt_table and the initialization of
the lock element is not needed since the lock is always initialized in
xt_table_register anyway.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter 01/09: remove "happy cracking" message

Don't spam logs for locally generated short packets. these can only
be generated by root.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: netns: remove nf_*_net() wrappers

Now that dev_net() exists, the usefullness of them is even less. Also they're
a big problem in resolving circular header dependencies necessary for
NOTRACK-in-netns patch. See below.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

[NETFILTER]: Use non-deprecated __RW_LOCK_UNLOCKED macro

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Patrick McHardy <kaber@trash.net>

[NETFILTER]: ip_tables: per-netns FILTER/MANGLE/RAW tables for real

Commit 9335f047fe61587ec82ff12fbb1220bcfdd32006 aka
"[NETFILTER]: ip_tables: per-netns FILTER, MANGLE, RAW"
added per-netns _view_ of iptables rules. They were shown to user, but
ignored by filtering code. Now that it's possible to at least ping loopback,
per-netns tables can affect filtering decisions.

netns is taken in case of
PRE_ROUTING, LOCAL_IN -- from in device,
POST_ROUTING, LOCAL_OUT -- from out device,
FORWARD -- from in device which should be equal to out device's netns.
This code is relatively new, so BUG_ON was plugged.

Wrappers were added to a) keep code the same from CONFIG_NET_NS=n users
(overwhelming majority), b) consolidate code in one place -- similar
changes will be done in ipv6 and arp netfilter code.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>

[NETFILTER]: ip_tables: per-netns FILTER, MANGLE, RAW

Now, iptables show and configure different set of rules in different
netnss'. Filtering decisions are still made by consulting only
init_net's set.

Changes are identical except naming so no splitting.

P.S.: one need to remove init_net checks in nf_sockopt.c and inet_create()
to see the effect.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: x_tables: return new table from {arp,ip,ip6}t_register_table()

Typical table module registers xt_table structure (i.e. packet_filter)
and link it to list during it. We can't use one template for it because
corresponding list_head will become corrupted. We also can't unregister
with template because it wasn't changed at all and thus doesn't know in
which list it is.

So, we duplicate template at the very first step of table registration.
Table modules will save it for use during unregistration time and actual
filtering.

Do it at once to not screw bisection.

P.S.: renaming i.e. packet_filter => __packet_filter is temporary until
full netnsization of table modules is done.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Mark hooks __read_mostly

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Introduce NF_INET_ hook values

The IPv4 and IPv6 hook values are identical, yet some code tries to figure
out the "correct" value by looking at the address family. Introduce NF_INET_*
values for both IPv4 and IPv6. The old values are kept in a #ifndef __KERNEL__
section for userspace compatibility.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Replace sk_buff ** with sk_buff *

With all the users of the double pointers removed, this patch mops up by
finally replacing all occurances of sk_buff ** in the netfilter API by
sk_buff *.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: iptable_{filter,mangle}: more descriptive "happy cracking" message

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Clean up table initialization

- move arp_tables initial table structure definitions to arp_tables.h
similar to ip_tables and ip6_tables

- use C99 initializers

- use initializer macros where possible

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Remove changelogs and CVS IDs

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IP]: Introduce ip_hdrlen()

For the common sequence "skb->nh.iph->ihl * 4", removing a good number of open
coded skb->nh.iph uses, now to go after the rest...

Just out of curiosity, here are the idioms found to get the same result:

skb->nh.iph->ihl << 2
skb->nh.iph->ihl<<2
skb->nh.iph->ihl * 4
skb->nh.iph->ihl*4
(skb->nh.iph)->ihl * sizeof(u32)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET] IPV4: Fix whitespace errors.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: {ip,ip6}_tables: use struct xt_table instead of redefined structure names

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Rethink mark field in struct flowi

Now that all protocols have been made aware of the mark
field it can be moved out of the union thus simplyfing
its usage.

The config options in the IPv4/IPv6/DECnet subsystems
to enable respectively disable mark based routing only
obfuscate the code with ifdefs, the cost for the
additional comparison in the flow key is insignificant,
and most distributions have all these options enabled
by default anyway. Therefore it makes sense to remove
the config options and enable mark based routing by
default.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Turn nfmark into generic mark

nfmark is being used in various subsystems and has become
the defacto mark field for all kinds of packets. Therefore
it makes sense to rename it to `mark' and remove the
dependency on CONFIG_NETFILTER.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: add type parameter to ip_route_me_harder

By adding a type parameter to ip_route_me_harder() the
expensive call to inet_addr_type() can be avoided in some cases.
A followup patch where ip_route_me_harder() is called from within
ip_vs_out() is one such example.

Signed-off-By: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: ipt annotations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: x_tables: remove unused argument to target functions

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[NETFILTER]: Clean up hook registration

Clean up hook registration by makeing use of the new mass registration and
unregistration helpers.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Rename init functions.

Every netfilter module uses `init' for its module_init() function and
`fini' or `cleanup' for its module_exit() function.

Problem is, this creates uninformative initcall_debug output and makes
ctags rather useless.

So go through and rename them all to $(filename)_init and
$(filename)_fini.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER] x_tables: Abstraction layer for {ip,ip6,arp}_tables

This monster-patch tries to do the best job for unifying the data
structures and backend interfaces for the three evil clones ip_tables,
ip6_tables and arp_tables. In an ideal world we would never have
allowed this kind of copy+paste programming... but well, our world
isn't (yet?) ideal.

o introduce a new x_tables module
o {ip,arp,ip6}_tables depend on this x_tables module
o registration functions for tables, matches and targets are only
wrappers around x_tables provided functions
o all matches/targets that are used from ip_tables and ip6_tables
are now implemented as xt_FOOBAR.c files and provide module aliases
to ipt_FOOBAR and ip6t_FOOBAR
o header files for xt_matches are in include/linux/netfilter/,
include/linux/netfilter_{ipv4,ipv6} contains compatibility wrappers
around the xt_FOOBAR.h headers

Based on this patchset we're going to further unify the code,
gradually getting rid of all the layer 3 specific assumptions.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Linux-2.6.12-rc2

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!