xfrm: fix unused variable warning if CONFIG_NETFILTER=n

After recent change 'x' is only used when CONFIG_NETFILTER is set:

net/ipv4/xfrm4_output.c: In function '__xfrm4_output':
net/ipv4/xfrm4_output.c:19:21: warning: unused variable 'x' [-Wunused-variable]
19 | struct xfrm_state *x = skb_dst(skb)->xfrm;

Expand the CONFIG_NETFILTER scope to avoid this.

Fixes: 2ab6096db2f1 ("xfrm: remove output_finish indirection from xfrm_state_afinfo")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: remove output_finish indirection from xfrm_state_afinfo

There are only two implementaions, one for ipv4 and one for ipv6.

Both are almost identical, they clear skb->cb[], set the TRANSFORMED flag
in IP(6)CB and then call the common xfrm_output() function.

By placing the IPCB handling into the common function, we avoid the need
for the output_finish indirection as the output functions can simply
use xfrm_output().

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: avoid extract_output indirection for ipv4

We can use a direct call for ipv4, so move the needed functions
to net/xfrm/xfrm_output.c and call them directly.

For ipv6 the indirection can be avoided as well but it will need
a bit more work -- to ease review it will be done in another patch.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: Always set XFRM_TRANSFORMED in xfrm{4,6}_output_finish

IPSKB_XFRM_TRANSFORMED and IP6SKB_XFRM_TRANSFORMED are skb flags set by
xfrm code to tell other skb handlers that the packet has been passed
through the xfrm output functions. Simplify the code and just always
set them rather than conditionally based on netfilter enabled thus
making the flag available for other users.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: Support iif matches in POSTROUTING

Instead of generally passing NULL to NF_HOOK_COND() for input device,
pass skb->dev which contains input device for routed skbs.

Note that iptables (both legacy and nft) reject rules with input
interface match from being added to POSTROUTING chains, but nftables
allows this.

Cc: Eric Garver <eric@garver.life>
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 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 as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

xfrm: store xfrm_mode directly, not its address

This structure is now only 4 bytes, so its more efficient
to cache a copy rather than its address.

No significant size difference in allmodconfig vmlinux.

With non-modular kernel that has all XFRM options enabled, this
series reduces vmlinux image size by ~11kb. All xfrm_mode
indirections are gone and all modes are built-in.

before (ipsec-next master):
text data bss dec filename
21071494 7233140 11104324 39408958 vmlinux.master

after this series:
21066448 7226772 11104324 39397544 vmlinux.patched

With allmodconfig kernel, the size increase is only 362 bytes,
even all the xfrm config options removed in this series are
modular.

before:
text data bss dec filename
15731286 6936912 4046908 26715106 vmlinux.master

after this series:
15731492 6937068 4046908 26715468 vmlinux

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: remove afinfo pointer from xfrm_mode

Adds an EXPORT_SYMBOL for afinfo_get_rcu, as it will now be called from
ipv6 in case of CONFIG_IPV6=m.

This change has virtually no effect on vmlinux size, but it reduces
afinfo size and allows followup patch to make xfrm modes const.

v2: mark if (afinfo) tests as likely (Sabrina)
re-fetch afinfo according to inner_mode in xfrm_prepare_input().

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: remove output indirection from xfrm_mode

Same is input indirection. Only exception: we need to export
xfrm_outer_mode_output for pktgen.

Increases size of vmlinux by about 163 byte:
Before:
text data bss dec filename
15730208 6936948 4046908 26714064 vmlinux

After:
15730311 6937008 4046908 26714227 vmlinux

xfrm_inner_extract_output has no more external callers, make it static.

v2: add IS_ENABLED(IPV6) guard in xfrm6_prepare_output
add two missing breaks in xfrm_outer_mode_output (Sabrina Dubroca)
add WARN_ON_ONCE for 'call AF_INET6 related output function, but
CONFIG_IPV6=n' case.
make xfrm_inner_extract_output static

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

net: xfrm: use skb_gso_validate_network_len() to check gso sizes

Replace skb_gso_network_seglen() with
skb_gso_validate_network_len(), as it considers the GSO_BY_FRAGS
case.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

xfrm: Add an IPsec hardware offloading API

This patch adds all the bits that are needed to do
IPsec hardware offload for IPsec states and ESP packets.
We add xfrmdev_ops to the net_device. xfrmdev_ops has
function pointers that are needed to manage the xfrm
states in the hardware and to do a per packet
offloading decision.

Joint work with:
Ilan Tayari <ilant@mellanox.com>
Guy Shapiro <guysh@mellanox.com>
Yossi Kuperman <yossiku@mellanox.com>

Signed-off-by: Guy Shapiro <guysh@mellanox.com>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: Fix pmtu discovery for local generated packets.

Commit 044a832a777 ("xfrm: Fix local error reporting crash
with interfamily tunnels") moved the setting of skb->protocol
behind the last access of the inner mode family to fix an
interfamily crash. Unfortunately now skb->protocol might not
be set at all, so we fail dispatch to the inner address family.
As a reault, the local error handler is not called and the
mtu value is not reported back to userspace.

We fix this by setting skb->protocol on message size errors
before we call xfrm_local_error.

Fixes: 044a832a7779c ("xfrm: Fix local error reporting crash with interfamily tunnels")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

dst: Pass net into dst->output

The network namespace is already passed into dst_output pass it into
dst->output lwt->output and friends.

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

net: Pass net into dst_output and remove dst_output_okfn

Replace dst_output_okfn with dst_output

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

netfilter: Add blank lines in callers of netfilter hooks

In code review it was noticed that I had failed to add some blank lines
in places where they are customarily used. Taking a second look at the
code I have to agree blank lines would be nice so I have added them
here.

Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: Pass net into okfn

This is immediately motivated by the bridge code that chains functions that
call into netfilter. Without passing net into the okfns the bridge code would
need to guess about the best expression for the network namespace to process
packets in.

As net is frequently one of the first things computed in continuation functions
after netfilter has done it's job passing in the desired network namespace is in
many cases a code simplification.

To support this change the function dst_output_okfn is introduced to
simplify passing dst_output as an okfn. For the moment dst_output_okfn
just silently drops the struct net.

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

netfilter: Pass struct net into the netfilter hooks

Pass a network namespace parameter into the netfilter hooks. At the
call site of the netfilter hooks the path a packet is taking through
the network stack is well known which allows the network namespace to
be easily and reliabily.

This allows the replacement of magic code like
"dev_net(state->in?:state->out)" that appears at the start of most
netfilter hooks with "state->net".

In almost all cases the network namespace passed in is derived
from the first network device passed in, guaranteeing those
paths will not see any changes in practice.

The exceptions are:
xfrm/xfrm_output.c:xfrm_output_resume() xs_net(skb_dst(skb)->xfrm)
ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont() ip_vs_conn_net(cp)
ipvs/ip_vs_xmit.c:ip_vs_send_or_cont() ip_vs_conn_net(cp)
ipv4/raw.c:raw_send_hdrinc() sock_net(sk)
ipv6/ip6_output.c:ip6_xmit() sock_net(sk)
ipv6/ndisc.c:ndisc_send_skb() dev_net(skb->dev) not dev_net(dst->dev)
ipv6/raw.c:raw6_send_hdrinc() sock_net(sk)
br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev

In all cases these exceptions seem to be a better expression for the
network namespace the packet is being processed in then the historic
"dev_net(in?in:out)". I am documenting them in case something odd
pops up and someone starts trying to track down what happened.

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

net: Merge dst_output and dst_output_sk

Add a sock paramter to dst_output making dst_output_sk superfluous.
Add a skb->sk parameter to all of the callers of dst_output
Have the callers of dst_output_sk call dst_output.

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

netfilter: Pass socket pointer down through okfn().

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>

xfrm: Fix local error reporting crash with interfamily tunnels

We set the outer mode protocol too early. As a result, the
local error handler might dispatch to the wrong address family
and report the error to a wrong socket type. We fix this by
setting the outer protocol to the skb after we accessed the
inner mode for the last time, right before we do the atcual
encapsulation where we switch finally to the outer mode.

Reported-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Tested-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

net: rename local_df to ignore_df

As suggested by several people, rename local_df to ignore_df,
since it means "ignore df bit if it is set".

Cc: Maciej Żenczykowski <maze@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ipv4: add a sock pointer to dst->output() path.

In the dst->output() path for ipv4, the code assumes the skb it has to
transmit is attached to an inet socket, specifically via
ip_mc_output() : The sk_mc_loop() test triggers a WARN_ON() when the
provider of the packet is an AF_PACKET socket.

The dst->output() method gets an additional 'struct sock *sk'
parameter. This needs a cascade of changes so that this parameter can
be propagated from vxlan to final consumer.

Fixes: 8f646c922d55 ("vxlan: keep original skb ownership")
Reported-by: lucien xin <lucien.xin@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

xfrm: Fix crash with ipv6 IPsec tunnel and NAT.

The ipv6 xfrm output path is not aware that packets can be
rerouted by NAT to not use IPsec. We crash in this case
because we expect to have a xfrm state at the dst_entry.
This crash happens if the ipv6 layer does IPsec and NAT
or if we have an interfamily IPsec tunnel with ipv4 NAT.

We fix this by checking for a NAT rerouted packet in each
address family and dst_output() to the new destination
in this case.

Reported-by: Martin Pelikan <martin.pelikan@gmail.com>
Tested-by: Martin Pelikan <martin.pelikan@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: revert ipv4 mtu determination to dst_mtu

In commit 0ea9d5e3e0e03a63b11392f5613378977dae7eca ("xfrm: introduce
helper for safe determination of mtu") I switched the determination of
ipv4 mtus from dst_mtu to ip_skb_dst_mtu. This was an error because in
case of IP_PMTUDISC_PROBE we fall back to the interface mtu, which is
never correct for ipv4 ipsec.

This patch partly reverts 0ea9d5e3e0e03a63b11392f5613378977dae7eca
("xfrm: introduce helper for safe determination of mtu").

Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: introduce helper for safe determination of mtu

skb->sk socket can be of AF_INET or AF_INET6 address family. Thus we
always have to make sure we a referring to the correct interpretation
of skb->sk.

We only depend on header defines to query the mtu, so we don't introduce
a new dependency to ipv6 by this change.

Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm: make local error reporting more robust

In xfrm4 and xfrm6 we need to take care about sockets of the other
address family. This could happen because a 6in4 or 4in6 tunnel could
get protected by ipsec.

Because we don't want to have a run-time dependency on ipv6 when only
using ipv4 xfrm we have to embed a pointer to the correct local_error
function in xfrm_state_afinet and look it up when returning an error
depending on the socket address family.

Thanks to vi0ss for the great bug report:
<https://bugzilla.kernel.org/show_bug.cgi?id=58691>

v2:
a) fix two more unsafe interpretations of skb->sk as ipv6 socket
(xfrm6_local_dontfrag and __xfrm6_output)
v3:
a) add an EXPORT_SYMBOL_GPL(xfrm_local_error) to fix a link error when
building ipv6 as a module (thanks to Steffen Klassert)

Reported-by: <vi0oss@gmail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

xfrm4: Don't call icmp_send on local error

Calling icmp_send() on a local message size error leads to
an incorrect update of the path mtu. So use ip_local_error()
instead to notify the socket about the error.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

xfrm: Assign the inner mode output function to the dst entry

As it is, we assign the outer modes output function to the dst entry
when we create the xfrm bundle. This leads to two problems on interfamily
scenarios. We might insert ipv4 packets into ip6_fragment when called
from xfrm6_output. The system crashes if we try to fragment an ipv4
packet with ip6_fragment. This issue was introduced with git commit
ad0081e4 (ipv6: Fragment locally generated tunnel-mode IPSec6 packets
as needed). The second issue is, that we might insert ipv4 packets in
netfilter6 and vice versa on interfamily scenarios.

With this patch we assign the inner mode output function to the dst entry
when we create the xfrm bundle. So xfrm4_output/xfrm6_output from the inner
mode is used and the right fragmentation and netfilter functions are called.
We switch then to outer mode with the output_finish functions.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: ipv4: use NFPROTO values for NF_HOOK invocation

The semantic patch that was used:
// <smpl>
@@
@@
(NF_HOOK
|NF_HOOK_COND
|nf_hook
)(
-PF_INET,
+NFPROTO_IPV4,
...)
// </smpl>

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

net: skb->dst accessors

Define three accessors to get/set dst attached to a skb

struct dst_entry *skb_dst(const struct sk_buff *skb)

void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)

void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;

Delete skb->dst field

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[IPSEC]: Fix inter address family IPsec tunnel handling.

Signed-off-by: Kazunori MIYAZAWA <kazunori@miyazawa.org>
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>

[IPSEC]: Remove nhoff from xfrm_input

The nhoff field isn't actually necessary in xfrm_input. For tunnel
mode transforms we now throw away the output IP header so it makes no
sense to fill in the nexthdr field. For transport mode we can now let
the function transport_finish do the setting and it knows where the
nexthdr field is.

The only other thing that needs the nexthdr field to be set is the
header extraction code. However, we can simply move the protocol
extraction out of the generic header extraction.

We want to minimise the amount of info we have to carry around between
transforms as this simplifies the resumption process for async crypto.

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

[IPSEC]: Merge most of the output path

As part of the work on asynchrnous cryptographic operations, we need
to be able to resume from the spot where they occur. As such, it
helps if we isolate them to one spot.

This patch moves most of the remaining family-specific processing into
the common output code.

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

[IPV4]: Add ip_local_out

Most callers of the LOCAL_OUT chain will set the IP packet length and
header checksum before doing so. They also share the same output
function dst_output.

This patch creates a new function called ip_local_out which does all
of that and converts the appropriate users over to it.

Apart from removing duplicate code, it will also help in merging the
IPsec output path once the same thing is done for IPv6.

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

[IPSEC]: Separate inner/outer mode processing on output

With inter-family transforms the inner mode differs from the outer
mode. Attempting to handle both sides from the same function means
that it needs to handle both IPv4 and IPv6 which creates duplication
and confusion.

This patch separates the two parts on the output path so that each
function deals with one family only.

In particular, the functions xfrm4_extract_output/xfrm6_extract_output
moves the pertinent fields from the IPv4/IPv6 IP headers into a
neutral format stored in skb->cb. This is then used by the outer mode
output functions to write the outer IP header. In this way the output
function no longer has to know about the inner address family.

Since the extract functions are only called by tunnel modes (the only
modes that can support inter-family transforms), I've also moved the
xfrm*_tunnel_check_size calls into them. This allows the correct ICMP
message to be sent as opposed to now where you might call icmp_send
with an IPv6 packet and vice versa.

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

[IPSEC]: Rename mode to outer_mode and add inner_mode

This patch adds a new field to xfrm states called inner_mode. The existing
mode object is renamed to outer_mode.

This is the first part of an attempt to fix inter-family transforms. As it
is we always use the outer family when determining which mode to use. As a
result we may end up shoving IPv4 packets into netfilter6 and vice versa.

What we really want is to use the inner family for the first part of outbound
processing and the outer family for the second part. For inbound processing
we'd use the opposite pairing.

I've also added a check to prevent silly combinations such as transport mode
with inter-family transforms.

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

[IPSEC]: Add missing BEET checks

Currently BEET mode does not reinject the packet back into the stack
like tunnel mode does. Since BEET should behave just like tunnel mode
this is incorrect.

This patch fixes this by introducing a flags field to xfrm_mode that
tells the IPsec code whether it should terminate and reinject the packet
back into the stack.

It then sets the flag for BEET and tunnel mode.

I've also added a number of missing BEET checks elsewhere where we check
whether a given mode is a tunnel or not.

Signed-off-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>

[IPSEC]: Move IP length/checksum setting out of transforms

This patch moves the setting of the IP length and checksum fields out of
the transforms and into the xfrmX_output functions. This would help future
efforts in merging the transforms themselves.

It also adds an optimisation to ipcomp due to the fact that the transport
offset is guaranteed to be zero.

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

[IPSEC]: Move common output code to xfrm_output

Most of the code in xfrm4_output_one and xfrm6_output_one are identical so
this patch moves them into a common xfrm_output function which will live
in net/xfrm.

In fact this would seem to fix a bug as on IPv4 we never reset the network
header after a transform which may upset netfilter later on.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>

[NET] IPV4: Fix whitespace errors.

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

[IPSEC]: output mode to take an xfrm state as input param

Expose IPSEC modes output path to take an xfrm state as input param.
This makes it consistent with the input mode processing (which already
takes the xfrm state as a param).

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

[XFRM]: Add XFRM_MODE_xxx for future use.

Transformation mode is used as either IPsec transport or tunnel.
It is required to add two more items, route optimization and inbound trigger
for Mobile IPv6.
Based on MIPL2 kernel patch.

This patch was also written by: Ville Nuorvala <vnuorval@tcs.hut.fi>

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

[NET]: Replace CHECKSUM_HW by CHECKSUM_PARTIAL/CHECKSUM_COMPLETE

Replace CHECKSUM_HW by CHECKSUM_PARTIAL (for outgoing packets, whose
checksum still needs to be completed) and CHECKSUM_COMPLETE (for
incoming packets, device supplied full checksum).

Patch originally from Herbert Xu, updated by myself for 2.6.18-rc3.

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

[NET] gso: Add skb_is_gso

This patch adds the wrapper function skb_is_gso which can be used instead
of directly testing skb_shinfo(skb)->gso_size. This makes things a little
nicer and allows us to change the primary key for indicating whether an skb
is GSO (if we ever want to do that).

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

[IPSEC]: Handle GSO packets

This patch segments GSO packets received by the IPsec stack. This can
happen when a NIC driver injects GSO packets into the stack which are
then forwarded to another host.

The primary application of this is going to be Xen where its backend
driver may inject GSO packets into dom0.

Of course this also can be used by other virtualisation schemes such as
VMWare or UML since the tap device could be modified to inject GSO packets
received through splice.

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

[IPSEC] xfrm: Abstract out encapsulation modes

This patch adds the structure xfrm_mode. It is meant to represent
the operations carried out by transport/tunnel modes.

By doing this we allow additional encapsulation modes to be added
without clogging up the xfrm_input/xfrm_output paths.

Candidate modes include 4-to-6 tunnel mode, 6-to-4 tunnel mode, and
BEET modes.

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

[IPSEC]: Fix IP ID selection

I was looking through the xfrm input/output code in order to abstract
out the address family specific encapsulation/decapsulation code. During
that process I found this bug in the IP ID selection code in xfrm4_output.c.

At that point dst is still the xfrm_dst for the current SA which
represents an internal flow as far as the IPsec tunnel is concerned.
Since the IP ID is going to sit on the outside of the encapsulated
packet, we obviously want the external flow which is just dst->child.

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

[XFRM]: Fix SNAT-related crash in xfrm4_output_finish

When a packet matching an IPsec policy is SNATed so it doesn't match any
policy anymore it looses its xfrm bundle, which makes xfrm4_output_finish
crash because of a NULL pointer dereference.

This patch directs these packets to the original output path instead. Since
the packets have already passed the POST_ROUTING hook, but need to start at
the beginning of the original output path which includes another
POST_ROUTING invocation, a flag is added to the IPCB to indicate that the
packet was rerouted and doesn't need to pass the POST_ROUTING hook again.

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

[NETFILTER]: Redo policy lookups after NAT when neccessary

When NAT changes the key used for the xfrm lookup it needs to be done
again. If a new policy is returned in POST_ROUTING the packet needs
to be passed to xfrm4_output_one manually after all hooks were called
because POST_ROUTING is called with fixed okfn (ip_finish_output).

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

[NETFILTER]: Fix xfrm lookup in ip_route_me_harder/ip6_route_me_harder

ip_route_me_harder doesn't use the port numbers of the xfrm lookup and
uses ip_route_input for non-local addresses which doesn't do a xfrm
lookup, ip6_route_me_harder doesn't do a xfrm lookup at all.

Use xfrm_decode_session and do the lookup manually, make sure both
only do the lookup if the packet hasn't been transformed already.

Makeing sure the lookup only happens once needs a new field in the
IP6CB, which exceeds the size of skb->cb. The size of skb->cb is
increased to 48b. Apparently the IPv6 mobile extensions need some
more room anyway.

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

[XFRM]: Netfilter IPsec output hooks

Call netfilter hooks before IPsec transforms. Packets visit the
FORWARD/LOCAL_OUT and POST_ROUTING hook before the first encapsulation
and the LOCAL_OUT and POST_ROUTING hook before each following tunnel mode
transform.

Patch from Herbert Xu <herbert@gondor.apana.org.au>:

Move the loop from dst_output into xfrm4_output/xfrm6_output since they're
the only ones who need to it. xfrm{4,6}_output_one() processes the first SA
all subsequent transport mode SAs and is called in a loop that calls the
netfilter hooks between each two calls.

In order to avoid the tail call issue, I've added the inline function
nf_hook which is nf_hook_slow plus the empty list check.

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

[IPSEC]: Add XFRM_STATE_NOPMTUDISC flag

This patch adds the flag XFRM_STATE_NOPMTUDISC for xfrm states. It is
similar to the nopmtudisc on IPIP/GRE tunnels. It only has an effect
on IPv4 tunnel mode states. For these states, it will ensure that the
DF flag is always cleared.

This is primarily useful to work around ICMP blackholes.

In future this flag could also allow a larger MTU to be set within the
tunnel just like IPIP/GRE tunnels. This could be useful for short haul
tunnels where temporary fragmentation outside the tunnel is desired over
smaller fragments inside the tunnel.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: James Morris <jmorris@redhat.com>
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!