BPFTOOL-NET(8) System Manager's Manual BPFTOOL-NET(8)
NAME
bpftool-net - tool for inspection of networking related bpf prog at-
tachments
SYNOPSIS
bpftool [OPTIONS] net COMMAND
OPTIONS := { { -j | --json } [{ -p | --pretty }] | { -d | --debug }
}
COMMANDS := { show | list | attach | detach | help }
NET COMMANDS
bpftool net { show | list } [ dev NAME ]
bpftool net attach ATTACH_TYPE PROG dev NAME [ overwrite ]
bpftool net detach ATTACH_TYPE dev NAME
bpftool net help
PROG := { id PROG_ID | pinned FILE | tag PROG_TAG }
ATTACH_TYPE := { xdp | xdpgeneric | xdpdrv | xdpoffload }
DESCRIPTION
bpftool net { show | list } [ dev NAME ]
List bpf program attachments in the kernel networking subsys-
tem.
Currently, device driver xdp attachments, tcx, netkit and
old-style tc classifier/action attachments, flow_dissector as
well as netfilter attachments are implemented, i.e., for pro-
gram types BPF_PROG_TYPE_XDP, BPF_PROG_TYPE_SCHED_CLS,
BPF_PROG_TYPE_SCHED_ACT, BPF_PROG_TYPE_FLOW_DISSECTOR,
BPF_PROG_TYPE_NETFILTER.
For programs attached to a particular cgroup, e.g.,
BPF_PROG_TYPE_CGROUP_SKB, BPF_PROG_TYPE_CGROUP_SOCK,
BPF_PROG_TYPE_SOCK_OPS and BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
users can use bpftool cgroup to dump cgroup attachments. For
sk_{filter, skb, msg, reuseport} and lwt/seg6 bpf programs,
users should consult other tools, e.g., iproute2.
The current output will start with all xdp program attach-
ments, followed by all tcx, netkit, then tc class/qdisc bpf
program attachments, then flow_dissector and finally netfil-
ter programs. Both xdp programs and tcx/netkit/tc programs
are ordered based on ifindex number. If multiple bpf programs
attached to the same networking device through tc, the order
will be first all bpf programs attached to tcx, netkit, then
tc classes, then all bpf programs attached to non clsact
qdiscs, and finally all bpf programs attached to root and
clsact qdisc.
bpftool net attach ATTACH_TYPE PROG dev NAME [ overwrite ]
Attach bpf program PROG to network interface NAME with type
specified by ATTACH_TYPE. Previously attached bpf program can
be replaced by the command used with overwrite option. Cur-
rently, only XDP-related modes are supported for ATTACH_TYPE.
ATTACH_TYPE can be of: xdp - try native XDP and fallback to
generic XDP if NIC driver does not support it; xdpgeneric -
Generic XDP. runs at generic XDP hook when packet already en-
ters receive path as skb; xdpdrv - Native XDP. runs earliest
point in driver's receive path; xdpoffload - Offload XDP.
runs directly on NIC on each packet reception;
bpftool net detach ATTACH_TYPE dev NAME
Detach bpf program attached to network interface NAME with
type specified by ATTACH_TYPE. To detach bpf program, same
ATTACH_TYPE previously used for attach must be specified.
Currently, only XDP-related modes are supported for AT-
TACH_TYPE.
bpftool net help
Print short help message.
OPTIONS
-h, --help
Print short help message (similar to bpftool help).
-V, --version
Print bpftool's version number (similar to bpftool version),
the number of the libbpf version in use, and optional fea-
tures that were included when bpftool was compiled. Optional
features include linking against LLVM or libbfd to provide
the disassembler for JIT-ted programs (bpftool prog dump
jited) and usage of BPF skeletons (some features like bpftool
prog profile or showing pids associated to BPF objects may
rely on it).
-j, --json
Generate JSON output. For commands that cannot produce JSON,
this option has no effect.
-p, --pretty
Generate human-readable JSON output. Implies -j.
-d, --debug
Print all logs available, even debug-level information. This
includes logs from libbpf as well as from the verifier, when
attempting to load programs.
EXAMPLES
# bpftool net
xdp:
eth0(2) driver id 198
tc:
eth0(2) htb name prefix_matcher.o:[cls_prefix_matcher_htb] id 111727 act []
eth0(2) clsact/ingress fbflow_icmp id 130246 act []
eth0(2) clsact/egress prefix_matcher.o:[cls_prefix_matcher_clsact] id 111726
eth0(2) clsact/egress cls_fg_dscp id 108619 act []
eth0(2) clsact/egress fbflow_egress id 130245
# bpftool -jp net
[{
"xdp": [{
"devname": "eth0",
"ifindex": 2,
"mode": "driver",
"id": 198
}
],
"tc": [{
"devname": "eth0",
"ifindex": 2,
"kind": "htb",
"name": "prefix_matcher.o:[cls_prefix_matcher_htb]",
"id": 111727,
"act": []
},{
"devname": "eth0",
"ifindex": 2,
"kind": "clsact/ingress",
"name": "fbflow_icmp",
"id": 130246,
"act": []
},{
"devname": "eth0",
"ifindex": 2,
"kind": "clsact/egress",
"name": "prefix_matcher.o:[cls_prefix_matcher_clsact]",
"id": 111726,
},{
"devname": "eth0",
"ifindex": 2,
"kind": "clsact/egress",
"name": "cls_fg_dscp",
"id": 108619,
"act": []
},{
"devname": "eth0",
"ifindex": 2,
"kind": "clsact/egress",
"name": "fbflow_egress",
"id": 130245,
}
]
}
]
# bpftool net attach xdpdrv id 16 dev enp6s0np0
# bpftool net
xdp:
enp6s0np0(4) driver id 16
# bpftool net attach xdpdrv id 16 dev enp6s0np0
# bpftool net attach xdpdrv id 20 dev enp6s0np0 overwrite
# bpftool net
xdp:
enp6s0np0(4) driver id 20
# bpftool net attach xdpdrv id 16 dev enp6s0np0
# bpftool net detach xdpdrv dev enp6s0np0
# bpftool net
xdp:
SEE ALSO
bpf(2), bpf-helpers(7), bpftool(8), bpftool-btf(8),
bpftool-cgroup(8), bpftool-feature(8), bpftool-gen(8),
bpftool-iter(8), bpftool-link(8), bpftool-map(8), bpftool-perf(8),
bpftool-prog(8), bpftool-struct_ops(8)
BPFTOOL-NET(8)
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