This patch fixes handling in case of link-local address compression. A
IPv6 link-local address is defined as fe80::/10 prefix which is also
what ipv6_addr_type checks for link-local addresses.

But IPHC compression for link-local addresses are for fe80::/64 types
only. This patch adds additional checks for zero padded bits in case of
link-local address compression to match on a fe80::/64 address only.
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch fixes the comments for SAM/DAM value.
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch solves the sparse warning:

net/6lowpan/debugfs.c:164:30: warning: symbol 'lowpan_ctx_pfx_fops' was
not declared. Should it be static?
net/6lowpan/debugfs.c:241:30: warning: symbol 'lowpan_context_fops' was
not declared. Should it be static?
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch fixes the return value in a case which should never occur.
Instead returning "-EINVAL" we return LOWPAN_IPHC_DAM_00 which is
invalid on context based addresses. Also change the WARN_ON_ONCE to
WARN_ONCE which was suggested by Dan Carpenter.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Bool variable 'fail' is always non-negative, it indicates an error if it
is true.

The problem has been detected using coccinelle script
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci
Signed-off-by: NAndrzej Hajda <a.hajda@samsung.com>
Acked-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

In case of multicast address we need to set always the LOWPAN_IPHC_M bit
and if a destination context identifier was found for a multicast
address then we need to set the LOWPAN_IPHC_DAC as well.
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch introduce support for IPHC stateful address compression. It
will offer the context table via one debugfs entry.
This debugfs has and directory for each cid entry for the context table.
Inside each cid directory there exists the following files:

 - "active": If the entry is added or deleted. The context table is
   original a list implementation, this flag will indicate if the
   context is part of list or not.
 - "prefix": The ipv6 prefix.
 - "prefix_length": The prefix length for the prefix.
 - "compression": The compression flag according RFC6775.

This part should be moved into sysfs after some testing time.

Also the debugfs entry contains a "show" file which is a pretty-printout
for the current context table information.
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patches moves the debugfs interface related register after
netdevice register. The function lowpan_dev_debugfs_init will use
"dev->name" which can be before register_netdevice a format string.
The function register_netdevice will evaluate the format string if
necessary and replace "dev->name" to the real interface name.
Reported-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch will introduce a 6lowpan entry into the debugfs if enabled.
Inside this 6lowpan directory we create a subdirectories of all 6lowpan
interfaces to offer a per interface debugfs support.
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch introduces register and unregister functionality for lowpan
interfaces. While register a lowpan interface there are several things
which need to be initialize by the 6lowpan subsystem. Upcoming
functionality need to register/unregister per interface components e.g.
debugfs entry.
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch moves the mcast compression algorithmn to an own function
like all other compression/decompression methods in iphc.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch reworks the handling of compression/decompression of traffic
class and flow label handling. The current method is hard to understand,
also doesn't checks if we can read the buffer from skb length.

I tried to put the shifting operations into static inline functions and
comment each steps which I did there to make it hopefully somewhat more
readable. The big mess to deal with that is the that the ipv6 header
bring the order "DSCP + ECN" but iphc uses "ECN + DSCP". Additional the
DCSP + ECN bits are splitted in ipv6_hdr inside the priority and
flow_lbl[0] fields.

I tested these compressions by using fakelb 802.15.4 driver and
manipulate the tc and flow label fields manually in function
"__ip6_local_out" before the skb will be send to lower layers. Then I
looked up the tc and flow label fields in wireshark on a wpan and lowpan
interface.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch has the main goal to delete shift operations. Instead we
doing masks and equals afterwards. E.g. for the SAM evaluation we
masking only the SAM value which fits in iphc1 byte, then comparing with
all possible SAM values over a switch case statement. We will not
shifting the SAM value to somewhat readable anymore.
Additional this patch slighty change the naming style like RFC 6282,
e.g. TTL to HLIM and we will drop an errno now if CID flag is set,
because we don't support it.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch removes the IPHC related defines for doing bit manipulation
from global 6lowpan header to the iphc file which should the only one
implementation which use these defines.

Also move next header compression defines to their nhc implementation.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch moves the iphc setting of next header commpression bit inside
iphc functionality. Setting of IPHC bits should be happen at iphc.c file
only.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch removes the lowpan_fetch_skb_u8 function for getting the iphc
bytes. Instead we using the generic which has a len parameter to tell
the amount of bytes to fetch.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch changes the lowpan_header_decompress function by removing
inklayer related information from parameters. This is currently for
supporting short and extended address for iphc handling in 802154.
We don't support short address handling anyway right now, but there
exists already code for handling short addresses in
lowpan_header_decompress.

The address parameters are also changed to a void pointer, so 6LoWPAN
linklayer specific code can put complex structures as these parameters
and cast it again inside the generic code by evaluating linklayer type
before. The order is also changed by destination address at first and
then source address, which is the same like all others functions where
destination is always the first, memcpy, dev_hard_header,
lowpan_header_compress, etc.

This patch also moves the fetching of iphc values from 6LoWPAN linklayer
specific code into the generic branch.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch changes the lowpan_header_compress function by removing
unused parameters like "len" and drop static value parameters of
protocol type. Instead we really check the protocol type inside inside
the skb structure. Also we drop the use of IEEE802154_ADDR_LEN which is
link-layer specific. Instead we using EUI64_ADDR_LEN which should always
the default case for now.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch introduces the LOWPAN_IPHC_MAX_HC_BUF_LEN define which
represent the worst-case supported IPHC buffer length. It's used to
allocate the stack buffer space for creating the IPHC header.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch moves values for all lowpan interface to the shared
implementation of 6lowpan. This patch also quietly fixes the forgotten
IFF_NO_QUEUE flag for the bluetooth 6LoWPAN interface. An identically
commit is 4afbc0db ("net: 6lowpan: convert to using IFF_NO_QUEUE") which
wasn't changed for bluetooth 6lowpan.

All 6lowpan interfaces should be virtual with IFF_NO_QUEUE, using EUI64
address length, the mtu size is 1280 (IPV6_MIN_MTU) and the netdev type
is ARPHRD_6LOWPAN.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch cleanups needed_headroom, needed_tailroom and hard_header_len
fields for wpan and lowpan interfaces.

For wpan interfaces the worst case mac header len should be part of
needed_headroom, currently this is set as hard_header_len, but
hard_header_len should be set to the minimum header length which xmit
call assumes and this is the minimum frame length of 802.15.4.
The hard_header_len value will check inside send callbacl of AF_PACKET
raw sockets.

For lowpan interfaces, if fragmentation isn't needed the skb will
call dev_hard_header for 802154 layer and queue it afterwards. This
happens without new skb allocation, so we need the same headroom and
tailroom lengths like 802154 inside 802154 6lowpan layer. At least we
assume as minimum header length an ipv6 header size.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch complete reworks the evaluation of 6lowpan dispatch value by
introducing a receive handler mechanism for each dispatch value.

A list of changes:

 - Doing uncompression on-the-fly when FRAG1 is received, this require
   some special handling for 802.15.4 lltype in generic 6lowpan branch
   for setting the payload length correct.
 - Fix dispatch mask for fragmentation.
 - Add IPv6 dispatch evaluation for FRAG1.
 - Add skb_unshare for dispatch which might manipulate the skb data
   buffer.

Cc: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch moves module_init of 6lowpan module into core functionality
of 6lowpan module. To load the ipv6 module at probing of the 6lowpan
module should be core functionality. Loading next header compression
modules is iphc specific. Nevertheless we only support IPHC for the
generic 6LoWPAN branch right now so we can put it into the core
functionality. If possible new compression formats are introduced nhc
should load only when iphc is build.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch introduced the 6lowpan netdev private data struct. We name it
lowpan_priv and it's placed at the beginning of netdev private data. All
lowpan interfaces should allocate this room at first of netdev private
data. 6LoWPAN LL private data can be allocate by additional netdev private
data, e.g. dev->priv_size should be "sizeof(struct lowpan_priv) +
sizeof(LL_LOWPAN_PRIVATE_DATA)".
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The lowpan_fetch_skb function is used to fetch the first byte,
which also increments the data pointer in skb structure,
making subsequent array lookup of byte 0 actually being byte 1.

To decompress the first byte of the Flow Label when the TF flag is
set to 0x01, the second half of the first byte is needed.

The patch fixes the extraction of the Flow Label field.
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The iphc module depends on CONFIG_IPV6, because it's not very useful to
build the module without IPv6 support. Recently an user reported about
issues for setting an IPv6 address to a 6LoWPAN interface. The issues
was solved by modprobe the ipv6 module before. To avoid such user issues
we try to request the ipv6 module when the 6LoWPAN module is loaded.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch adds other known rfc6282 compression formats to the nhc
framework. These compression formats are known but not implemented yet.
For now this is useful to printout a warning which compression format
isn't supported.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Cc: Martin Townsend <mtownsend1973@gmail.com>
Reviewed-by: NStefan Schmidt <s.schmidt@samsung.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch move UDP header compression and uncompression into the
generic 6LoWPAN nhc header compression layer. Moreover this patch
activates the nhc layer compression in iphc compression and
uncompression functions.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Cc: Martin Townsend <mtownsend1973@gmail.com>
Reviewed-by: NStefan Schmidt <s.schmidt@samsung.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch adds a generic next header compression layer interface. There
exists various methods to do a header compression after 6LoWPAN header
to save payload. This introduce a generic nhc header which allow a
simple adding of a new header compression format instead of a static
implementation inside the 6LoWPAN header compression and uncompression
function.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Cc: Martin Townsend <mtownsend1973@gmail.com>
Reviewed-by: NStefan Schmidt <s.schmidt@samsung.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This might change and we already deliver a copy of the license with
the kernel. This was already removed form the ieee802154 code but
missed here.
Signed-off-by: NStefan Schmidt <s.schmidt@samsung.com>
Acked-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Currently we ensure that the skb is freed on every error path in IPHC
decompression which makes it easy to introduce skb leaks.  By centralising
the skb_free into the receive function it makes future decompression routines
easier to maintain.  It does come at the expense of ensuring that the skb
passed into the decompression routine must not be copied.
Signed-off-by: NMartin Townsend <mtownsend1973@gmail.com>
Acked-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 you use RAW sockets the transport header offset is not set by the
ipv6 stack so when we get to the udp header compression it does not
compress the right part of the packet.

This patch adds a check for this scenario and sets the transport
header offset.
Signed-off-by: NSimon Vincent <simon.vincent@xsilon.com>
Acked-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

As we have decouple decompression from data delivery we can now rename all
occurences of process_data in receive path.
Signed-off-by: NMartin Townsend <mtownsend1973@gmail.com>
Acked-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>