Currently, 6lowpan creates one 802.15.4 MAC header for the original
packet the device was given by upper layers and reuses this header for
all fragments, if fragmentation is required. This also reuses frame
sequence numbers, which must not happen. 6lowpan also has issues with
fragmentation in the presence of security headers, since those may imply
the presence of trailing fields that are not accounted for by the
fragmentation code right now.

Fix both of these issues by properly allocating fragment skbs with
headromm and tailroom as specified by the underlying device, create one
header for each skb instead of reusing the original header, let the
underlying device do the rest.
Signed-off-by: NPhoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current mac_cb handling of ieee802154 is rather awkward and limited.
Decompose the single flags field into multiple fields with the meanings
of each subfield of the flags field to make future extensions (for
example, link-layer security) easier. Also don't set the frame sequence
number in upper layers, since that's a thing the MAC is supposed to set
on frame transmit - we set it on header creation, but assuming that
upper layers do not blindly duplicate our headers, this is fine.
Signed-off-by: NPhoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ieee802154 sockets do not properly unshare received skbs, which leads to
panics (at least) when they are used in conjunction with 6lowpan, so
run skb_share_check on received skbs.
6lowpan also contains a use-after-free, which is trivially fixed by
replacing the inlined skb_share_check with the explicit call.
Signed-off-by: NPhoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Tested-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Have mac802154 header_ops.create fail with -EMSGSIZE if the length
passed will be too large to fit a frame. Since 6lowpan will ensure that
no packet payload will be too large, pass a length of 0 there. 802.15.4
dgram sockets will also return -EMSGSIZE on payloads larger than the
device MTU instead of -EINVAL.
Signed-off-by: NPhoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change all internal uses of ieee802154_addr_sa to ieee802154_addr,
except for those instances that communicate directly with userspace.
Signed-off-by: NPhoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the operations on 802.15.4 header structs introduced in a previous
patch to create and parse all headers in the mac802154 stack. This patch
reduces code duplication between different parts of the mac802154 stack
that needed information from headers, and also fixes a few bugs that
seem to have gone unnoticed until now:

 * 802.15.4 dgram sockets would return a slightly incorrect value for
   the SIOCINQ ioctl
 * mac802154 would not drop frames with the "security enabled" bit set,
   even though it does not support security, in violation of the
   standard
Signed-off-by: NPhoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enable sparse warnings about endianness, replace the remaining fields
regarding network operations without explicit endianness annotations
with such that are annotated, and propagate this through the entire
stack.

Uses of ieee802154_addr_sa are not changed yet, this patch is only
concerned with all other fields (such as address filters, operation
parameters and the likes).
Signed-off-by: NPhoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The struct as currently defined uses host byte order for some fields,
and most big endian/EUI display byte order for other fields. Inside the
stack, endianness should ideally match network byte order where possible
to minimize the number of byteswaps done in critical paths, but this
patch does not address this; it is only preparatory.
Signed-off-by: NPhoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The use of __constant_<foo> has been unnecessary for quite awhile now.

Make these uses consistent with the rest of the kernel.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This header is used by bluetooth and ieee802154 branch. This patch
move this header to the include/net directory to avoid a use of a
relative path in include.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The initialization of the tag value doesn't matter at begin of
fragmentation. This patch removes the initialization to zero.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch drops the current way of 6lowpan fragmentation on receiving
side and replace it with a implementation which use the inet_frag api.
The old fragmentation handling has some race conditions and isn't
rfc4944 compatible. Also adding support to match fragments on
destination address, source address, tag value and datagram_size
which is missing in the current implementation.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Detected with:

./scripts/checkpatch.pl --strict -f net/ieee802154/6lowpan_rtnl.c
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have a 6lowpan.c file and 6lowpan.ko file. To avoid confusing we
should move 6lowpan.c to 6lowpan_rtnl.c. Then we can support multiple
source files for 6lowpan module.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fix the fragmentation on sending side according to rfc4944.

Also add improvement to use the full payload of a PDU which calculate
the nearest divided to 8 payload length for the fragmentation datagram
size attribute.

The main issue is that the datagram size of fragmentation header use the
ipv6 payload length, but rfc4944 says it's the ipv6 payload length inclusive
network header size (and transport header size if compressed).
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a device ndo_start_xmit() calls again dev_queue_xmit(),
lockdep can complain because dev_queue_xmit() is re-entered and the
spinlocks protecting tx queues share a common lockdep class.

Same issue was fixed for bonding/l2tp/ppp in commits

0daa2303 ("[PATCH] bonding: lockdep annotation")
49ee4920 ("bonding: set qdisc_tx_busylock to avoid LOCKDEP splat")
23d3b8bf ("net: qdisc busylock needs lockdep annotations ")
303c07db ("ppp: set qdisc_tx_busylock to avoid LOCKDEP splat ")
Reported-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Tested-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 8df8c56a (6lowpan: Moving generic compression code into 6lowpan_iphc.c)
left pointer 'hdr' unused - remove it.

Detected by Coverity: CID 1164868.
Signed-off-by: NChristian Engelmayer <cengelma@gmx.at>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In function lowpan_header_create(), we invoke the following code
construct:

  struct ipv6hdr *hdr;
  ...
  hdr = ipv6_hdr(skb);
  ...
  if (...)
    memcpy(hc06_ptr + 1, &hdr->flow_lbl[1], 2);
  else
    memcpy(hc06_ptr, &hdr, 4);

Where the else path of the condition, that is, non-compression
path, calls memcpy() with a pointer to struct ipv6hdr *hdr as
source, thus two levels of indirection. This cannot be correct,
and likely only one level of pointer was intended as source
buffer for memcpy() here.

Fixes: 44331fe2 ("IEEE802.15.4: 6LoWPAN basic support")
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Werner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are several issues on current debug behaviour.
This patch fix the following issues:

- Fix debug printout only if DEBUG is defined.
- Move debug functions of 6LoWPAN code into 6lowpan header.
- Cleanup codestyle of debug functions.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Because the IEEE 802154 and Bluetooth share the IP header compression
and uncompression code, the common code is moved to 6lowpan_iphc.c
file.
Signed-off-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Acked-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

If priority/traffic class field in IPv6 header is set (seen when
using ssh), the uncompression sets the TC and Flow fields incorrectly.

Example:

This is IPv6 header of a sent packet. Note the priority/TC (=1) in
the first byte.

00000000: 61 00 00 00 00 2c 06 40 fe 80 00 00 00 00 00 00
00000010: 02 02 72 ff fe c6 42 10 fe 80 00 00 00 00 00 00
00000020: 02 1e ab ff fe 4c 52 57

This gets compressed like this in the sending side

00000000: 72 31 04 06 02 1e ab ff fe 4c 52 57 ec c2 00 16
00000010: aa 2d fe 92 86 4e be c6 ....

In the receiving end, the packet gets uncompressed to this
IPv6 header

00000000: 60 06 06 02 00 2a 1e 40 fe 80 00 00 00 00 00 00
00000010: 02 02 72 ff fe c6 42 10 fe 80 00 00 00 00 00 00
00000020: ab ff fe 4c 52 57 ec c2

First four bytes are set incorrectly and we have also lost
two bytes from destination address.

The fix is to switch the case values in switch statement
when checking the TC field.
Signed-off-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We recently added a new error path and it needs a dev_put().

Fixes: 7adac1ec ('6lowpan: Only make 6lowpan links to IEEE802154 devices')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch drops the direct memcpy on skb and uses the right skb
memcpy functions. Also remove an unnecessary check if plen is non zero.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is necessary to access network header with the skb_network_header
function instead of calculate the position with mac_len, etc.
Do the same for the transport header, when we replace the IPv6 header
with the 6LoWPAN header.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Set the mac header length while creating the 802.15.4 mac header.

Drop the function for recalculate mac header length in upper layers
which was static and works for intra pan communication only.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On receiving side we don't need to set any headers in skb because the
6LoWPAN layer do not access it. Currently these values will set twice
after calling netif_rx.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes the assignment of skb->dev. We don't need it here because
we use the netdev_alloc_skb_ip_align function which already sets the
skb->dev.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch uses the netdev_alloc_skb instead dev_alloc_skb function and
drops the seperate assignment to skb->dev.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The err variable can only be zero in this case.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a lowpan link to a wpan device is created, set the hardware address
of the lowpan link to that of the wpan device.
Signed-off-by: NAlan Ott <alan@signal11.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Refuse to create 6lowpan links if the actual hardware interface is
of any type other than ARPHRD_IEEE802154.
Signed-off-by: NAlan Ott <alan@signal11.us>
Suggested-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Handle context based address when an unspecified address is given.
For other context based address we print a warning and drop the packet
because we don't support it right now.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch drops the pre and postcount calculation from the
lowpan_uncompress_addr function.We use instead a switch/case
over address_mode value. The original implementation has several
bugs in this function and it was hard to decrypt how it works.
To make it maintainable and fix these bugs this patch basically
reimplements lowpan_uncompress_addr from scratch.

A list of bugs we found in the current implementation:

1) Properly support uncompression of short-address based IPv6 addresses
   (instead of basically copying garbage)

2) Fix use and uncompression of long-addresses based IPv6 addresses

3) Add missing ff:fe00 in the case of SAM/DAM = 2 and M = 0
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add function to uncompress multicast address.
This function split the uncompress function for a multicast address
in a seperate function.

To uncompress a multicast address is different than a other
non-multicasts addresses according to rfc6282.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a new 6lowpan fragment is received, a skbuff is allocated for
the reassembled packet. However when a 6lowpan packet compresses
link-local addresses based on link-layer addresses, the processing
function relies on the skb mac control block to find the related
link-layer address.

This patch copies the control block from the first fragment into
the newly allocated skb to keep a trace of the link-layer addresses
in case of a link-local compressed address.

Edit: small changes on comment issue
Signed-off-by: NDavid Hauweele <david@hauweele.net>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch simplify the handling to set fields inside of struct ipv6hdr
to zero. Instead of setting some memory regions with memset to zero we
initialize the whole ipv6hdr to zero.

This is a simplification for parsing the 6lowpan header for the upcomming
patches.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Reviewed-by: NWerner Almesberger <werner@almesberger.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>