delta/linux.git/include/uapi/linux/if_tun.h, branch proc-cmdline

tun: allow to attach ebpf socket filter

2018-01-17T20:32:10+00:00

This patch allows userspace to attach eBPF filter to tun. This will
allow to implement VM dataplane filtering in a more efficient way
compared to cBPF filter by allowing either qemu or libvirt to
attach eBPF filter to tun.

Signed-off-by: Jason Wang 
Signed-off-by: David S. Miller

tun: add eBPF based queue selection method

2017-12-05T17:01:49+00:00

This patch introduces an eBPF based queue selection method. With this,
the policy could be offloaded to userspace completely through a new
ioctl TUNSETSTEERINGEBPF.

Signed-off-by: Jason Wang 
Acked-by: Willem de Bruijn 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-11-04T00:26:51+00:00

Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller

License cleanup: add SPDX license identifier to uapi header files with a license

2017-11-02T10:20:11+00:00

Many user space API headers have licensing information, which is either
incomplete, badly formatted or just a shorthand for referring to the
license under which the file is supposed to be.  This makes it hard for
compliance tools to determine the correct license.

Update these files with an SPDX license identifier.  The identifier was
chosen based on the license information in the file.

GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license
identifier with the added 'WITH Linux-syscall-note' exception, which is
the officially assigned exception identifier for the kernel syscall
exception:

   NOTE! This copyright does *not* cover user programs that use kernel
   services by normal system calls - this is merely considered normal use
   of the kernel, and does *not* fall under the heading of "derived work".

This exception makes it possible to include GPL headers into non GPL
code, without confusing license compliance tools.

Headers which have either explicit dual licensing or are just licensed
under a non GPL license are updated with the corresponding SPDX
identifier and the GPLv2 with syscall exception identifier.  The format
is:
        ((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE)

SPDX license identifiers are a legally binding shorthand, which can be
used instead of the full boiler plate text.  The update does not remove
existing license information as this has to be done on a case by case
basis and the copyright holders might have to be consulted. This will
happen in a separate step.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.  See the previous patch in this series for the
methodology of how this patch was researched.

Reviewed-by: Kate Stewart 
Reviewed-by: Philippe Ombredanne 
Reviewed-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

tun: enable napi_gro_frags() for TUN/TAP driver

2017-09-26T03:16:13+00:00

Add a TUN/TAP receive mode that exercises the napi_gro_frags()
interface. This mode is available only in TAP mode, as the interface
expects packets with Ethernet headers.

Furthermore, packets follow the layout of the iovec_iter that was
received. The first iovec is the linear data, and every one after the
first is a fragment. If there are more fragments than the max number,
drop the packet. Additionally, invoke eth_get_headlen() to exercise flow
dissector code and to verify that the header resides in the linear data.

The napi_gro_frags() mode requires setting the IFF_NAPI_FRAGS option.
This is imposed because this mode is intended for testing via tools like
syzkaller and packetdrill, and the increased flexibility it provides can
introduce security vulnerabilities. This flag is accepted only if the
device is in TAP mode and has the IFF_NAPI flag set as well. This is
done because both of these are explicit requirements for correct
operation in this mode.

Signed-off-by: Petar Penkov 
Cc: Eric Dumazet 
Cc: Mahesh Bandewar 
Cc: Willem de Bruijn 
Cc: davem@davemloft.net
Cc: ppenkov@stanford.edu
Acked-by: Mahesh Bandewar 
Signed-off-by: David S. Miller

tun: enable NAPI for TUN/TAP driver

2017-09-26T03:16:13+00:00

Changes TUN driver to use napi_gro_receive() upon receiving packets
rather than netif_rx_ni(). Adds flag IFF_NAPI that enables these
changes and operation is not affected if the flag is disabled.  SKBs
are constructed upon packet arrival and are queued to be processed
later.

The new path was evaluated with a benchmark with the following setup:
Open two tap devices and a receiver thread that reads in a loop for
each device. Start one sender thread and pin all threads to different
CPUs. Send 1M minimum UDP packets to each device and measure sending
time for each of the sending methods:
	napi_gro_receive():	4.90s
	netif_rx_ni():		4.90s
	netif_receive_skb():	7.20s

Signed-off-by: Petar Penkov 
Cc: Eric Dumazet 
Cc: Mahesh Bandewar 
Cc: Willem de Bruijn 
Cc: davem@davemloft.net
Cc: ppenkov@stanford.edu
Acked-by: Mahesh Bandewar 
Signed-off-by: David S. Miller

macvtap/tun: cross-endian support for little-endian hosts

2015-06-01T13:48:56+00:00

The VNET_LE flag was introduced to fix accesses to virtio 1.0 headers
that are always little-endian. It can also be used to handle the special
case of a legacy little-endian device implemented by a big-endian host.

Let's add a flag and ioctls for big-endian devices as well. If both flags
are set, little-endian wins.

Since this is isn't a common usecase, the feature is controlled by a kernel
config option (not set by default).

Both macvtap and tun are covered by this patch since they share the same
API with userland.

Signed-off-by: Greg Kurz 

Signed-off-by: Michael S. Tsirkin 
Reviewed-by: David Gibson

if_tun: drop broken IFF_VNET_LE

2014-12-16T16:19:42+00:00

Everyone should use TUNSETVNETLE/TUNGETVNETLE instead.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller

if_tun: add TUNSETVNETLE/TUNGETVNETLE

2014-12-16T16:19:41+00:00

ifreq flags field is only 16 bit wide, so setting IFF_VNET_LE there has
no effect:
doesn't fit in two bytes.

The tests passed apparently because they have an even number of bugs,
all cancelling out.

Luckily we didn't release a kernel with this flag, so it's
not too late to fix this.

Add TUNSETVNETLE/TUNGETVNETLE to really achieve the purpose
of IFF_VNET_LE.

This has an added benefit that if we ever want a BE flag,
we won't have to deal with weird configurations like
setting both LE and BE at the same time.

IFF_VNET_LE will be dropped in a follow-up patch.

Reported-by: Dan Carpenter 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller

tun: add VNET_LE flag

2014-12-09T10:05:30+00:00

virtio 1.0 modified virtio net header format,
making all fields little endian.

Users can tweak header format before submitting it to tun,
but this means more data copies where none were necessary.
And if the iovec is in RO memory, this means we might
need to split iovec also means we might in theory overflow
iovec max size.

This patch adds a simpler way for applications to handle this,
using new "little endian" flag in tun.
As a result, tun simply byte-swaps header fields as appropriate.
This is a NOP on LE architectures.

Signed-off-by: Michael S. Tsirkin