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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-23 12:43:55 +08:00
linux-next/include
Daniel Borkmann 7d672345ed bpf: add generic bpf_csum_diff helper
For L4 checksums, we currently have bpf_l4_csum_replace() helper. It's
currently limited to handle 2 and 4 byte changes in a header and feeds the
from/to into inet_proto_csum_replace{2,4}() helpers of the kernel. When
working with IPv6, for example, this makes it rather cumbersome to deal
with, similarly when editing larger parts of a header.

Instead, extend the API in a more generic way: For bpf_l4_csum_replace(),
add a case for header field mask of 0 to change the checksum at a given
offset through inet_proto_csum_replace_by_diff(), and provide a helper
bpf_csum_diff() that can generically calculate a from/to diff for arbitrary
amounts of data.

This can be used in multiple ways: for the bpf_l4_csum_replace() only
part, this even provides us with the option to insert precalculated diffs
from user space f.e. from a map, or from bpf_csum_diff() during runtime.

bpf_csum_diff() has a optional from/to stack buffer input, so we can
calculate a diff by using a scratchbuffer for scenarios where we're
inserting (from is NULL), removing (to is NULL) or diffing (from/to buffers
don't need to be of equal size) data. Also, bpf_csum_diff() allows to
feed a previous csum into csum_partial(), so the function can also be
cascaded.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-21 22:07:09 -05:00
..
acpi Merge branches 'acpica', 'acpi-video' and 'acpi-fan' 2016-01-21 00:41:59 +01:00
asm-generic Merge branch 'akpm' (patches from Andrew) 2016-01-21 12:32:08 -08:00
clocksource
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2016-01-22 11:58:43 -08:00
drm drm/atomic-helper: Export framebuffer_changed() 2016-01-20 08:55:43 +08:00
dt-bindings ARM: SoC driver updates for v4.5 2016-01-20 18:42:30 -08:00
keys
kvm
linux bpf: add new arg_type that allows for 0 sized stack buffer 2016-02-21 22:07:09 -05:00
math-emu
media [media] media-entitiy: add a function to create multiple links 2016-01-11 12:19:26 -02:00
memory
misc
net VXLAN: Support outer IPv4 Tx checksums by default 2016-02-21 22:05:50 -05:00
pcmcia
ras
rdma IB/mlx4: Enable send of RoCE QP1 packets with IP/UDP headers 2016-01-19 15:35:01 -05:00
rxrpc
scsi Initial roundup of 4.5 merge window patches 2016-01-23 18:45:06 -08:00
soc ARM: SoC driver updates for v4.5 2016-01-20 18:42:30 -08:00
sound ALSA: timer: Introduce disconnect op to snd_timer_instance 2016-01-21 17:51:42 +01:00
target Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2016-01-20 17:20:53 -08:00
trace sunvnet: Add support for perf LDC event tracing 2016-02-07 14:13:05 -05:00
uapi bpf: add generic bpf_csum_diff helper 2016-02-21 22:07:09 -05:00
video
xen Merge branch 'for-4.5/drivers' of git://git.kernel.dk/linux-block 2016-01-21 18:19:38 -08:00
Kbuild