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| author | John Fastabend <john.fastabend@gmail.com> | 2018-11-26 23:16:17 +0100 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-11-28 22:07:57 +0100 |
| commit | 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 (patch) | |
| tree | 500458a8fb23f87db2411ad0849f06f05caedb48 /include/uapi | |
| parent | Merge branch 'libbpf-versioning-doc' (diff) | |
| download | linux-7246d8ed4dcce23f7509949a77be15fa9f0e3d28.tar.xz linux-7246d8ed4dcce23f7509949a77be15fa9f0e3d28.zip | |
bpf: helper to pop data from messages
This adds a BPF SK_MSG program helper so that we can pop data from a
msg. We use this to pop metadata from a previous push data call.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/linux/bpf.h | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 23e2031a43d4..597afdbc1ab9 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -2268,6 +2268,19 @@ union bpf_attr { * * Return * 0 on success, or a negative error in case of failure. + * + * int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 pop, u64 flags) + * Description + * Will remove *pop* bytes from a *msg* starting at byte *start*. + * This may result in **ENOMEM** errors under certain situations if + * an allocation and copy are required due to a full ring buffer. + * However, the helper will try to avoid doing the allocation + * if possible. Other errors can occur if input parameters are + * invalid either due to *start* byte not being valid part of msg + * payload and/or *pop* value being to large. + * + * Return + * 0 on success, or a negative erro in case of failure. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -2360,7 +2373,8 @@ union bpf_attr { FN(map_push_elem), \ FN(map_pop_elem), \ FN(map_peek_elem), \ - FN(msg_push_data), + FN(msg_push_data), \ + FN(msg_pop_data), /* integer value in 'imm' field of BPF_CALL instruction selects which helper * function eBPF program intends to call |