I'm actually surprised at how much was involved.  At first glance it
appears that the neighbour table data structures are already split by
network device so all that should be needed is to modify the user
interface commands to filter the set of neighbours by the network
namespace of their devices.

However a couple things turned up while I was reading through the
code.  The proxy neighbour table allows entries with no network
device, and the neighbour parms are per network device (except for the
defaults) so they now need a per network namespace default.

So I updated the two structures (which surprised me) with their very
own network namespace parameter.  Updated the relevant lookup and
destroy routines with a network namespace parameter and modified the
code that interacts with users to filter out neighbour table entries
for devices of other namespaces.

I'm a little concerned that we can modify and display the global table
configuration and from all network namespaces.  But this appears good
enough for now.

I keep thinking modifying the neighbour table to have per network
namespace instances of each table type would should be cleaner.  The
hash table is already dynamically sized so there are it is not a
limiter.  The default parameter would be straight forward to take care
of.  However when I look at the how the network table is built and
used I still find some assumptions that there is only a single
neighbour table for each type of table in the kernel.  The netlink
operations, neigh_seq_start, the non-core network users that call
neigh_lookup.  So while it might be doable it would require more
refactoring than my current approach of just doing a little extra
filtering in the code.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NDaniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IPv6 specific thing is wrongly removed from transformation at net-2.6.25.
This patch recovers it with current design.

o Update "path" of xfrm_dst since IPv6 transformation should
  care about routing changes. It is required by MIPv6 and
  off-link destined IPsec.
o Rename nfheader_len which is for non-fragment transformation used by
  MIPv6 to rt6i_nfheader_len as IPv6 name space.
Signed-off-by: NMasahide NAKAMURA <nakam@linux-ipv6.org>
Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

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

This patch creates a new function called ip6_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.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The dst member nfheader_len is only used by IPv6.  It's also currently
creating a rather ugly alignment hole in struct dst.  Therefore this patch
moves it from there into struct rt6_info.

It also reorders the fields in rt6_info to minimize holes.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We only need to set nfheader_len in the top xfrm dst.  This is because
we only ever read the nfheader_len from the top xfrm dst.

It is also easier to count nfheader_len as part of header_len which
then lets us remove the ugly wrapper functions for incrementing and
decrementing header lengths in xfrm6_policy.c.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As it is ip_append_data only counts page fragments to the skb that
allocated it.  As such it means that the first skb gets hit with a
4K charge even though it might have only used a fraction of it while
all subsequent skb's that use the same page gets away with no charge
at all.

This bug was exposed by the UDP accounting patch.

[ The wmem_alloc bumping needs to be moved with the truesize,
  noticed by Takahiro Yasui.  -DaveM ]
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IPv6 stack doesn't increment OutNoRoutes counter when IP datagrams
is being discarded because no route could be found to transmit them
to their destination. IPv6 stack should increment the counter.
Incidentally, IPv4 stack increments that counter in such situation.
Signed-off-by: NMitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ip6_push_pending_frames and ip6_flush_pending_frames do the
same things to flush the sock's cork. Move this into a separate
function and save ~100 bytes from the .text
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In some places, the result of skb_headroom() is compared to an unsigned
integer, and in others, the result is compared to a signed integer.  Make
the comparisons consistent and correct.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Uninline netfilter okfns for those cases where gcc can generate tail-calls.

Before:
   text    data     bss     dec     hex filename
8994153 1016524  524652 10535329         a0c1a1 vmlinux

After:
   text    data     bss     dec     hex filename
8992761 1016524  524652 10533937         a0bc31 vmlinux
-------------------------------------------------------
  -1392

All cases have been verified to generate tail-calls with and without netfilter.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Background: RFC 4293 deprecates existing individual, named ICMP
type counters to be replaced with the ICMPMsgStatsTable. This table
includes entries for both IPv4 and IPv6, and requires counting of all
ICMP types, whether or not the machine implements the type.

These patches "remove" (but not really) the existing counters, and
replace them with the ICMPMsgStats tables for v4 and v6.
It includes the named counters in the /proc places they were, but gets the
values for them from the new tables. It also counts packets generated
from raw socket output (e.g., OutEchoes, MLD queries, RA's from
radvd, etc).

Changes:
1) create icmpmsg_statistics mib
2) create icmpv6msg_statistics mib
3) modify existing counters to use these
4) modify /proc/net/snmp to add "IcmpMsg" with all ICMP types
        listed by number for easy SNMP parsing
5) modify /proc/net/snmp printing for "Icmp" to get the named data
        from new counters.
[new to 2nd revision]
6) support per-interface ICMP stats
7) use common macro for per-device stat macros
Signed-off-by: NDavid L Stevens <dlstevens@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IPv6 IPsec tunnel gateway incorrectly sends redirect to
router or sender when network device the IPsec tunnelled packet
is arrived is the same as the one the decapsulated packet
is sent.

With this patch, it omits to send the redirect when the forwarding
skbuff carries secpath, since such skbuff should be assumed as
a decapsulated packet from IPsec tunnel by own.

It may be a rare case for an IPsec security gateway, however
it is not rare when the gateway is MIPv6 Home Agent since
the another tunnel end-point is Mobile Node and it changes
the attached network.
Signed-off-by: NMasahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some of skbs in sk->write_queue do not have skb->dst because
we do not fill skb->dst when we allocate new skb in append_data().

BTW, I think we may not need to (or we should not) increment some stats
when using corking; if 100 sendmsg() (with MSG_MORE) result in 2 packets,
how many should we increment?

If 100, we should set skb->dst for every queued skbs.

If 1 (or 2 (*)), we increment the stats for the first queued skb and
we should just skip incrementing OutDiscards for the rest of queued skbs,
adn we should also impelement this semantics in other places;
e.g., we should increment other stats just once, not 100 times.

*: depends on the place we are discarding the datagram.

I guess should just increment by 1 (or 2).
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If ICMP6 message with "Packet Too Big" is received after send SCTP DATA,
kernel panic will occur when SCTP DATA is send again.

This is because of a bad dest address when call to skb_copy_bits().

The messages sequence is like this:

Endpoint A                             Endpoint B
                               <-------  SCTP DATA (size=1432)
ICMP6 message ------->
(Packet Too Big pmtu=1280)
                               <-------  Resend SCTP DATA (size=1432)
------------kernel panic---------------

 printing eip:
c05be62a
*pde = 00000000
Oops: 0002 [#1]
SMP
Modules linked in: scomm l2cap bluetooth ipv6 dm_mirror dm_mod video output sbs battery lp floppy sg i2c_piix4 i2c_core pcnet32 mii button ac parport_pc parport ide_cd cdrom serio_raw mptspi mptscsih mptbase scsi_transport_spi sd_mod scsi_mod ext3 jbd ehci_hcd ohci_hcd uhci_hcd
CPU:    0
EIP:    0060:[<c05be62a>]    Not tainted VLI
EFLAGS: 00010282   (2.6.23-rc2 #1)
EIP is at skb_copy_bits+0x4f/0x1ef
eax: 000004d0   ebx: ce12a980   ecx: 00000134   edx: cfd5a880
esi: c8246858   edi: 00000000   ebp: c0759b14   esp: c0759adc
ds: 007b   es: 007b   fs: 00d8  gs: 0000  ss: 0068
Process swapper (pid: 0, ti=c0759000 task=c06d0340 task.ti=c0713000)
Stack: c0759b88 c0405867 ce12a980 c8bff838 c789c084 00000000 00000028 cfd5a880
       d09f1890 000005dc 0000007b ce12a980 cfd5a880 c8bff838 c0759b88 d09bc521
       000004d0 fffff96c 00000200 00000100 c0759b50 cfd5a880 00000246 c0759bd4
Call Trace:
 [<c0405e1d>] show_trace_log_lvl+0x1a/0x2f
 [<c0405ecd>] show_stack_log_lvl+0x9b/0xa3
 [<c040608d>] show_registers+0x1b8/0x289
 [<c0406271>] die+0x113/0x246
 [<c0625dbc>] do_page_fault+0x4ad/0x57e
 [<c0624642>] error_code+0x72/0x78
 [<d09bc521>] ip6_output+0x8e5/0xab2 [ipv6]
 [<d09bcec1>] ip6_xmit+0x2ea/0x3a3 [ipv6]
 [<d0a3f2ca>] sctp_v6_xmit+0x248/0x253 [sctp]
 [<d0a3c934>] sctp_packet_transmit+0x53f/0x5ae [sctp]
 [<d0a34bf8>] sctp_outq_flush+0x555/0x587 [sctp]
 [<d0a34d3c>] sctp_retransmit+0xf8/0x10f [sctp]
 [<d0a3d183>] sctp_icmp_frag_needed+0x57/0x5b [sctp]
 [<d0a3ece2>] sctp_v6_err+0xcd/0x148 [sctp]
 [<d09cf1ce>] icmpv6_notify+0xe6/0x167 [ipv6]
 [<d09d009a>] icmpv6_rcv+0x7d7/0x849 [ipv6]
 [<d09be240>] ip6_input+0x1dc/0x310 [ipv6]
 [<d09be965>] ipv6_rcv+0x294/0x2df [ipv6]
 [<c05c3789>] netif_receive_skb+0x2d2/0x335
 [<c05c5733>] process_backlog+0x7f/0xd0
 [<c05c58f6>] net_rx_action+0x96/0x17e
 [<c042e722>] __do_softirq+0x64/0xcd
 [<c0406f37>] do_softirq+0x5c/0xac
 =======================
Code: 00 00 29 ca 89 d0 2b 45 e0 89 55 ec 85 c0 7e 35 39 45 08 8b 55 e4 0f 4e 45 08 8b 75 e0 8b 7d dc 89 c1 c1 e9 02 03 b2 a0 00 00 00 <f3> a5 89 c1 83 e1 03 74 02 f3 a4 29 45 08 0f 84 7b 01 00 00 01
EIP: [<c05be62a>] skb_copy_bits+0x4f/0x1ef SS:ESP 0068:c0759adc
Kernel panic - not syncing: Fatal exception in interrupt

Arnaldo says:
====================
Thanks! I'm to blame for this one, problem was introduced in:

b0e380b1

@@ -761,7 +762,7 @@ slow_path:
                /*
                 *      Copy a block of the IP datagram.
                 */
-               if (skb_copy_bits(skb, ptr, frag->h.raw, len))
+               if (skb_copy_bits(skb, ptr, skb_transport_header(skb),
len))
                        BUG();
                left -= len;
====================
Signed-off-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The TRACE target can be used to follow IP and IPv6 packets through
the ruleset.
Signed-off-by: NJozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: NPatrick NcHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes MIPv6 loadable module named "mip6".

Here is a modprobe.conf(5) example to load it automatically
when user application uses XFRM state for MIPv6:

alias xfrm-type-10-43 mip6
alias xfrm-type-10-60 mip6

Some MIPv6 feature is not included by this modular, however,
it should not be affected to other features like either IPsec
or IPv6 with and without the patch.
We may discuss XFRM, MH (RAW socket) and ancillary data/sockopt
separately for future work.

Loadable features:
* MH receiving check (to send ICMP error back)
* RO header parsing and building (i.e. RH2 and HAO in DSTOPTS)
* XFRM policy/state database handling for RO

These are NOT covered as loadable:
* Home Address flags and its rule on source address selection
* XFRM sub policy (depends on its own kernel option)
* XFRM functions to receive RO as IPv6 extension header
* MH sending/receiving through raw socket if user application
  opens it (since raw socket allows to do so)
* RH2 sending as ancillary data
* RH2 operation with setsockopt(2)
Signed-off-by: NMasahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When an IPv6 router is forwarding a packet with a link-local scope source
address off-link, RFC 4007 requires it to send an ICMPv6 destination
unreachable with code 2 ("not neighbor"), but Linux doesn't. Fix below.
Signed-off-by: NDavid L Stevens <dlstevens@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add IP(V6)_PMTUDISC_PROBE value for IP(V6)_MTU_DISCOVER.  This option forces
us not to fragment, but does not make use of the kernel path MTU discovery.
That is, it allows for user-mode MTU probing (or, packetization-layer path
MTU discovery).  This is particularly useful for diagnostic utilities, like
traceroute/tracepath.
Signed-off-by: NJohn Heffner <jheffner@psc.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adds a check in ip6_fragment() mirroring ip_fragment() for packets
that we can't fragment, and sends an ICMP Packet Too Big message
in response.
Signed-off-by: NJohn Heffner <jheffner@psc.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To clearly state the intent of copying from linear sk_buffs, _offset being a
overly long variant but interesting for the sake of saving some bytes.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Right now Xen has a horrible hack that lets it forward packets with
partial checksums.  One of the reasons that CHECKSUM_PARTIAL and
CHECKSUM_COMPLETE were added is so that we can get rid of this hack
(where it creates two extra bits in the skbuff to essentially mirror
ip_summed without being destroyed by the forwarding code).

I had forgotten that I've already gone through all the deivce drivers
last time around to make sure that they're looking at ip_summed ==
CHECKSUM_PARTIAL rather than ip_summed != 0 on transmit.  In any case,
I've now done that again so it should definitely be safe.

Unfortunately nobody has yet added any code to update CHECKSUM_COMPLETE
values on forward so we I'm setting that to CHECKSUM_NONE.  This should
be safe to remove for bridging but I'd like to check that code path
first.

So here is the patch that lets us get rid of the hack by preserving
ip_summed (mostly) on forwarded packets.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)

Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Renaming skb->h to skb->transport_header, skb->nh to skb->network_header and
skb->mac to skb->mac_header, to match the names of the associated helpers
(skb[_[re]set]_{transport,network,mac}_header).
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For the common sequence "skb->h.raw - skb->nh.raw", similar to skb->mac_len,
that is precalculated tho, don't think we need to bloat skb with one more
member, so just use this new helper, reducing the number of non-skbuff.h
references to the layer headers even more.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ip6_nd_hdr is always called immediately after a alloc_skb + skb_reserve
sequence, i.e. when skb->tail is equal to skb->data, making it correct to use
skb_reset_network_header().
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This unifies the codes to copy netfilter related datas. Before copying,
nf_copy() puts original members in destination skb.
Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For the common, open coded 'skb->h.raw = skb->data' operation, so that we can
later turn skb->h.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple cases:

skb->h.raw = skb->data;
skb->h.raw = {skb_push|[__]skb_pull}()

The next ones will handle the slightly more "complex" cases.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now the skb->nh union has just one member, .raw, i.e. it is just like the
skb->mac union, strange, no? I'm just leaving it like that till the transport
layer is done with, when we'll rename skb->mac.raw to skb->mac_header (or
->mac_header_offset?), ditto for ->{h,nh}.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For the cases where the network header is being set to a offset from skb->data.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For the places where we need a pointer to the network header, it is still legal
to touch skb->nh.raw directly if just adding to, subtracting from or setting it
to another layer header.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For the quite common 'skb->nh.raw - skb->data' sequence.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb_push updates and returns skb->data, so we can just call
skb_reset_network_header after the call to skb_push.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For the common, open coded 'skb->nh.raw = skb->data' operation, so that we can
later turn skb->nh.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For the common, open coded 'skb->mac.raw = skb->data' operation, so that we can
later turn skb->mac.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Nominally an autoconfigured IPv6 address is added to an interface in the
Tentative state (as per RFC 2462).  Addresses in this state remain in this
state while the Duplicate Address Detection process operates on them to
determine their uniqueness on the network.  During this period, these
tentative addresses may not be used for communication, increasing the time
before a node may be able to communicate on a network.  Using Optimistic
Duplicate Address Detection, autoconfigured addresses may be used
immediately for communication on the network, as long as certain rules are
followed to avoid conflicts with other nodes during the Duplicate Address
Detection process.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

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

The hard header cache is in the main output path, so using
seqlock instead of reader/writer lock should reduce overhead.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The commit "[IPV6]: Use kmemdup" (commit-id:
af879cc7) broke IPv6 fragments.

Bug was spotted by Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>