linux.git/tools/bpf/bpftool/Documentation, branch v6.7

bpftool: Extend net dump with netkit progs

2023-10-24T23:07:32+00:00

Add support to dump BPF programs on netkit via bpftool. This includes both
the BPF link and attach ops programs. Dumped information contain the attach
location, function entry name, program ID and link ID when applicable.

Example with tc BPF link:

  # ./bpftool net
  xdp:

  tc:
  nk1(22) netkit/peer tc1 prog_id 43 link_id 12

  [...]

Example with json dump:

  # ./bpftool net --json | jq
  [
    {
      "xdp": [],
      "tc": [
        {
          "devname": "nk1",
          "ifindex": 18,
          "kind": "netkit/primary",
          "name": "tc1",
          "prog_id": 29,
          "prog_flags": [],
          "link_id": 8,
          "link_flags": []
        }
      ],
      "flow_dissector": [],
      "netfilter": []
    }
  ]

Signed-off-by: Daniel Borkmann 
Reviewed-by: Quentin Monnet 
Acked-by: Martin KaFai Lau 
Link: https://lore.kernel.org/r/20231024214904.29825-6-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau

bpftool: Add support for cgroup unix socket address hooks

2023-10-12T00:27:55+00:00

Add the necessary plumbing to hook up the new cgroup unix sockaddr
hooks into bpftool.

Signed-off-by: Daan De Meyer 
Acked-by: Quentin Monnet 
Link: https://lore.kernel.org/r/20231011185113.140426-7-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau

bpftool: Extend net dump with tcx progs

2023-07-19T17:07:28+00:00

Add support to dump fd-based attach types via bpftool. This includes both
the tc BPF link and attach ops programs. Dumped information contain the
attach location, function entry name, program ID and link ID when applicable.

Example with tc BPF link:

  # ./bpftool net
  xdp:

  tc:
  bond0(4) tcx/ingress cil_from_netdev prog_id 784 link_id 10
  bond0(4) tcx/egress cil_to_netdev prog_id 804 link_id 11

  flow_dissector:

  netfilter:

Example with tc BPF attach ops:

  # ./bpftool net
  xdp:

  tc:
  bond0(4) tcx/ingress cil_from_netdev prog_id 654
  bond0(4) tcx/egress cil_to_netdev prog_id 672

  flow_dissector:

  netfilter:

Currently, permanent flags are not yet supported, so 'unknown' ones are dumped
via NET_DUMP_UINT_ONLY() and once we do have permanent ones, we dump them as
human readable string.

Signed-off-by: Daniel Borkmann 
Reviewed-by: Quentin Monnet 
Link: https://lore.kernel.org/r/20230719140858.13224-7-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov

bpf: Replace deprecated -target with --target= for Clang

2023-06-29T13:46:17+00:00

The -target option has been deprecated since clang 3.4 in 2013. Therefore, use
the preferred --target=bpf form instead. This also matches how we use --target=
in scripts/Makefile.clang.

Signed-off-by: Fangrui Song 
Signed-off-by: Daniel Borkmann 
Acked-by: Yonghong Song 
Acked-by: Quentin Monnet 
Link: https://github.com/llvm/llvm-project/commit/274b6f0c87a6a1798de0a68135afc7f95def6277
Link: https://lore.kernel.org/bpf/20230624001856.1903733-1-maskray@google.com

bpftool: Specify XDP Hints ifname when loading program

2023-05-23T14:55:06+00:00

Add ability to specify a network interface used to resolve XDP hints
kfuncs when loading program through bpftool.

Usage:

  bpftool prog load [...] xdpmeta_dev 

Writing just 'dev ' instead of 'xdpmeta_dev' is a very probable
mistake that results in not very descriptive errors,
so 'bpftool prog load [...] dev ' syntax becomes deprecated,
followed by 'bpftool map create [...] dev ' for consistency.

Now, to offload program, execute:

  bpftool prog load [...] offload_dev 

To offload map:

  bpftool map create [...] offload_dev 

'dev ' still performs offloading in the commands above, but now
triggers a warning and is excluded from bash completion.

'xdpmeta_dev' and 'offload_dev' are mutually exclusive options, because
'xdpmeta_dev' basically makes a program device-bound without loading it
onto the said device. For now, offloaded programs cannot use XDP hints [0],
but if this changes, using 'offload_dev ' should cover this case.

  [0] https://lore.kernel.org/bpf/a5a636cc-5b03-686f-4be0-000383b05cfc@linux.dev

Signed-off-by: Larysa Zaremba 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Quentin Monnet 
Link: https://lore.kernel.org/bpf/20230517160103.1088185-1-larysa.zaremba@intel.com

bpftool: Update doc to explain struct_ops register subcommand.

2023-04-21T18:10:10+00:00

The "struct_ops register" subcommand now allows for an optional *LINK_DIR*
to be included. This specifies the directory path where bpftool will pin
struct_ops links with the same name as their corresponding map names.

Signed-off-by: Kui-Feng Lee 
Reviewed-by: Quentin Monnet 
Link: https://lore.kernel.org/r/20230420002822.345222-2-kuifeng@meta.com
Signed-off-by: Alexei Starovoitov

bpftool: Support "opcodes", "linum", "visual" simultaneously

2023-04-06T04:27:27+00:00

When dumping a program, the keywords "opcodes" (for printing the raw
opcodes), "linum" (for displaying the filename, line number, column
number along with the source code), and "visual" (for generating the
control flow graph for translated programs) are mutually exclusive. But
there's no reason why they should be. Let's make it possible to pass
several of them at once. The "file FILE" option, which makes bpftool
output a binary image to a file, remains incompatible with the others.

Signed-off-by: Quentin Monnet 
Link: https://lore.kernel.org/r/20230405132120.59886-6-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov

bpftool: Fix documentation about line info display for prog dumps

2023-04-06T04:27:27+00:00

The documentation states that when line_info is available when dumping a
program, the source line will be displayed "by default". There is no
notion of "default" here: the line is always displayed if available,
there is no way currently to turn it off.

In the next sentence, the documentation states that if "linum" is used
on the command line, the relevant filename, line, and column will be
displayed "on top of the source line". This is incorrect, as they are
currently displayed on the right side of the source line (or on top of
the eBPF instruction, not the source).

This commit fixes the documentation to address these points.

Signed-off-by: Quentin Monnet 
Link: https://lore.kernel.org/r/20230405132120.59886-2-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov

bpftool: remove support of --legacy option for bpftool

2022-11-21T00:17:46+00:00

Following:
  commit bd054102a8c7 ("libbpf: enforce strict libbpf 1.0 behaviors")
  commit 93b8952d223a ("libbpf: deprecate legacy BPF map definitions")

The --legacy option is no longer relevant as libbpf no longer supports
it. libbpf_set_strict_mode() is a no-op operation.

Signed-off-by: Sahid Orentino Ferdjaoui 
Acked-by: Yonghong Song 
Reviewed-by: Quentin Monnet 
Link: https://lore.kernel.org/r/20221120112515.38165-2-sahid.ferdjaoui@industrialdiscipline.com
Signed-off-by: Alexei Starovoitov

bpftool: Support new cgroup local storage

2022-10-26T06:19:19+00:00

Add support for new cgroup local storage

Acked-by: Quentin Monnet 
Signed-off-by: Yonghong Song 
Link: https://lore.kernel.org/r/20221026042901.674177-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov