diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2018-04-18 23:34:17 +0200 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-04-18 23:34:18 +0200 |
| commit | 7f3249fb1231c38a005a9ccfc480c84ed4af1b71 (patch) | |
| tree | 89bf245d8d4d86f46b4bea11473d9441b1f53782 /include/uapi | |
| parent | 0c90f2243ec67eeacf9624ae52ab43c734fe0e93 (diff) | |
| parent | c6ffd1ff785675c4a572c79f0e55ba5735edbaa0 (diff) | |
Merge branch 'bpf-xdp-adjust-tail'
Nikita V. Shirokov says:
====================
In this patch series i'm add new bpf helper which allow to manupulate
xdp's data_end pointer. right now only "shrinking" (reduce packet's size
by moving pointer) is supported (and i see no use case for "growing").
Main use case for such helper is to be able to generate controll (ICMP)
messages from XDP context. such messages usually contains first N bytes
from original packets as a payload, and this is exactly what this helper
would allow us to do (see patch 3 for sample program, where we generate
ICMP "packet too big" message). This helper could be usefull for load
balancing applications where after additional encapsulation, resulting
packet could be bigger then interface MTU.
Aside from new helper this patch series contains minor changes in device
drivers (for ones which requires), so they would recal packet's length
not only when head pointer was adjusted, but if tail's one as well.
v2->v3:
* adding missed "signed off by" in v2
v1->v2:
* fixed kbuild warning
* made offset eq 0 invalid for xdp_bpf_adjust_tail
* splitted bpf_prog_test_run fix and selftests in sep commits
* added SPDX licence where applicable
* some reshuffling in patches order (tests now in the end)
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/linux/bpf.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index c5ec89732a8d..9a2d1a04eb24 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -755,6 +755,13 @@ union bpf_attr { * @addr: pointer to struct sockaddr to bind socket to * @addr_len: length of sockaddr structure * Return: 0 on success or negative error code + * + * int bpf_xdp_adjust_tail(xdp_md, delta) + * Adjust the xdp_md.data_end by delta. Only shrinking of packet's + * size is supported. + * @xdp_md: pointer to xdp_md + * @delta: A negative integer to be added to xdp_md.data_end + * Return: 0 on success or negative on error */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -821,7 +828,8 @@ union bpf_attr { FN(msg_apply_bytes), \ FN(msg_cork_bytes), \ FN(msg_pull_data), \ - FN(bind), + FN(bind), \ + FN(xdp_adjust_tail), /* integer value in 'imm' field of BPF_CALL instruction selects which helper * function eBPF program intends to call |