1BPFTOOL-NET(8)                                                  BPFTOOL-NET(8)
2
3
4

NAME

6       bpftool-net - tool for inspection of netdev/tc related bpf prog attach‐
7       ments
8

SYNOPSIS

10          bpftool [OPTIONS] net COMMAND
11
12          OPTIONS := { { -j | --json } [{ -p | --pretty }] | { -d | --debug  }
13          | { -l | --legacy } }
14
15          COMMANDS := { show | list | attach | detach | help }
16

NET COMMANDS

18       bpftool net { show | list } [ dev NAME ]
19       bpftool net attach ATTACH_TYPE PROG dev NAME [ overwrite ]
20       bpftool net detach ATTACH_TYPE dev NAME
21       bpftool net help
22
23       PROG := { id PROG_ID | pinned FILE | tag PROG_TAG }
24       ATTACH_TYPE := { xdp | xdpgeneric | xdpdrv | xdpoffload }
25
26

DESCRIPTION

28          bpftool net { show | list } [ dev NAME ]
29                 List bpf program attachments in the kernel networking subsys‐
30                 tem.
31
32                 Currently, only device driver xdp attachments and  tc  filter
33                 classification/action  attachments are implemented, i.e., for
34                 program            types             BPF_PROG_TYPE_SCHED_CLS,
35                 BPF_PROG_TYPE_SCHED_ACT  and BPF_PROG_TYPE_XDP.  For programs
36                 attached     to     a      particular      cgroup,      e.g.,
37                 BPF_PROG_TYPE_CGROUP_SKB,          BPF_PROG_TYPE_CGROUP_SOCK,
38                 BPF_PROG_TYPE_SOCK_OPS  and   BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
39                 users can use bpftool cgroup to dump cgroup attachments.  For
40                 sk_{filter, skb, msg, reuseport} and lwt/seg6  bpf  programs,
41                 users should consult other tools, e.g., iproute2.
42
43                 The  current  output  will start with all xdp program attach‐
44                 ments, followed by all tc  class/qdisc  bpf  program  attach‐
45                 ments. Both xdp programs and tc programs are ordered based on
46                 ifindex number. If multiple bpf programs attached to the same
47                 networking  device through tc filter, the order will be first
48                 all bpf programs attached to tc classes, then  all  bpf  pro‐
49                 grams attached to non clsact qdiscs, and finally all bpf pro‐
50                 grams attached to root and clsact qdisc.
51
52          bpftool net attach ATTACH_TYPE PROG dev NAME [ overwrite ]
53                 Attach bpf program PROG to network interface NAME  with  type
54                 specified by ATTACH_TYPE. Previously attached bpf program can
55                 be replaced by the command used with overwrite option.   Cur‐
56                 rently, only XDP-related modes are supported for ATTACH_TYPE.
57
58                 ATTACH_TYPE  can  be of: xdp - try native XDP and fallback to
59                 generic XDP if NIC driver does not support it;  xdpgeneric  -
60                 Generic XDP. runs at generic XDP hook when packet already en‐
61                 ters receive path as skb; xdpdrv - Native XDP. runs  earliest
62                 point  in  driver's  receive  path; xdpoffload - Offload XDP.
63                 runs directly on NIC on each packet reception;
64
65          bpftool net detach ATTACH_TYPE dev NAME
66                 Detach bpf program attached to network  interface  NAME  with
67                 type  specified  by  ATTACH_TYPE. To detach bpf program, same
68                 ATTACH_TYPE previously used for  attach  must  be  specified.
69                 Currently,  only  XDP-related  modes  are  supported  for AT‐
70                 TACH_TYPE.
71
72          bpftool net help
73                 Print short help message.
74

OPTIONS

76          -h, --help
77                 Print short help message (similar to bpftool help).
78
79          -V, --version
80                 Print bpftool's version number (similar to bpftool  version),
81                 the  number  of  the libbpf version in use, and optional fea‐
82                 tures that were included when bpftool was compiled.  Optional
83                 features include linking against libbfd to provide the disas‐
84                 sembler for JIT-ted programs (bpftool prog  dump  jited)  and
85                 usage  of BPF skeletons (some features like bpftool prog pro‐
86                 file or showing pids associated to BPF objects  may  rely  on
87                 it).
88
89          -j, --json
90                 Generate  JSON output. For commands that cannot produce JSON,
91                 this option has no effect.
92
93          -p, --pretty
94                 Generate human-readable JSON output. Implies -j.
95
96          -d, --debug
97                 Print all logs available, even debug-level information.  This
98                 includes  logs from libbpf as well as from the verifier, when
99                 attempting to load programs.
100
101          -l, --legacy
102                 Use legacy libbpf mode which has more relaxed BPF program re‐
103                 quirements.  By default, bpftool has more strict requirements
104                 about section names, changes pinning logic and  doesn't  sup‐
105                 port some of the older non-BTF map declarations.
106
107                 See
108                 https://github.com/libbpf/libbpf/wiki/Libbpf:-the-road-to-v1.0
109                 for details.
110

EXAMPLES

112       # bpftool net
113
114
115          xdp:
116          eth0(2) driver id 198
117
118          tc:
119          eth0(2) htb name prefix_matcher.o:[cls_prefix_matcher_htb] id 111727 act []
120          eth0(2) clsact/ingress fbflow_icmp id 130246 act []
121          eth0(2) clsact/egress prefix_matcher.o:[cls_prefix_matcher_clsact] id 111726
122          eth0(2) clsact/egress cls_fg_dscp id 108619 act []
123          eth0(2) clsact/egress fbflow_egress id 130245
124
125       # bpftool -jp net
126
127
128          [{
129                  "xdp": [{
130                          "devname": "eth0",
131                          "ifindex": 2,
132                          "mode": "driver",
133                          "id": 198
134                      }
135                  ],
136                  "tc": [{
137                          "devname": "eth0",
138                          "ifindex": 2,
139                          "kind": "htb",
140                          "name": "prefix_matcher.o:[cls_prefix_matcher_htb]",
141                          "id": 111727,
142                          "act": []
143                      },{
144                          "devname": "eth0",
145                          "ifindex": 2,
146                          "kind": "clsact/ingress",
147                          "name": "fbflow_icmp",
148                          "id": 130246,
149                          "act": []
150                      },{
151                          "devname": "eth0",
152                          "ifindex": 2,
153                          "kind": "clsact/egress",
154                          "name": "prefix_matcher.o:[cls_prefix_matcher_clsact]",
155                          "id": 111726,
156                      },{
157                          "devname": "eth0",
158                          "ifindex": 2,
159                          "kind": "clsact/egress",
160                          "name": "cls_fg_dscp",
161                          "id": 108619,
162                          "act": []
163                      },{
164                          "devname": "eth0",
165                          "ifindex": 2,
166                          "kind": "clsact/egress",
167                          "name": "fbflow_egress",
168                          "id": 130245,
169                      }
170                  ]
171              }
172          ]
173
174       # bpftool net attach xdpdrv id 16 dev enp6s0np0
175       # bpftool net
176
177
178          xdp:
179          enp6s0np0(4) driver id 16
180
181       # bpftool net attach xdpdrv id 16 dev enp6s0np0
182       # bpftool net attach xdpdrv id 20 dev enp6s0np0 overwrite
183       # bpftool net
184
185
186          xdp:
187          enp6s0np0(4) driver id 20
188
189       # bpftool net attach xdpdrv id 16 dev enp6s0np0
190       # bpftool net detach xdpdrv dev enp6s0np0
191       # bpftool net
192
193
194          xdp:
195

SEE ALSO

197          bpf(2),       bpf-helpers(7),       bpftool(8),      bpftool-btf(8),
198          bpftool-cgroup(8),        bpftool-feature(8),        bpftool-gen(8),
199          bpftool-iter(8),  bpftool-link(8),  bpftool-map(8), bpftool-perf(8),
200          bpftool-prog(8), bpftool-struct_ops(8)
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205                                                                BPFTOOL-NET(8)
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