3 Commits

Author SHA1 Message Date
Stanislav Fomichev
13e56ec2cc selftests/bpf: use thoff instead of nhoff in BPF flow dissector
We are returning thoff from the flow dissector, not the nhoff. Pass
thoff along with nhoff to the bpf program (initially thoff == nhoff)
and expect flow dissector amend/return thoff, not nhoff.

This avoids confusion, when by the time bpf flow dissector exits,
nhoff == thoff, which doesn't make much sense.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-12-07 13:38:12 -08:00
Alexei Starovoitov
70e88c758a selftests/bpf: fix bpf_flow.c build
fix the following build error:
clang -I. -I./include/uapi -I../../../include/uapi -idirafter /usr/local/include -idirafter /data/users/ast/llvm/bld/lib/clang/7.0.0/include -idirafter /usr/include -Wno-compare-distinct-pointer-types \
	 -O2 -target bpf -emit-llvm -c bpf_flow.c -o - |      \
llc -march=bpf -mcpu=generic  -filetype=obj -o /data/users/ast/bpf-next/tools/testing/selftests/bpf/bpf_flow.o
LLVM ERROR: 'dissect' label emitted multiple times to assembly file
make: *** [/data/users/ast/bpf-next/tools/testing/selftests/bpf/bpf_flow.o] Error 1

Fixes: 9c98b13cc3bb ("flow_dissector: implements eBPF parser")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-09-14 12:09:05 -07:00
Petar Penkov
9c98b13cc3 flow_dissector: implements eBPF parser
This eBPF program extracts basic/control/ip address/ports keys from
incoming packets. It supports recursive parsing for IP encapsulation,
and VLAN, along with IPv4/IPv6 and extension headers.  This program is
meant to show how flow dissection and key extraction can be done in
eBPF.

Link: http://vger.kernel.org/netconf2017_files/rx_hardening_and_udp_gso.pdf
Signed-off-by: Petar Penkov <ppenkov@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-09-14 12:04:33 -07:00