linux-stable/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
Daniel Müller 1ba5ad36e0 bpftool: Use libbpf_bpf_attach_type_str
This change switches bpftool over to using the recently introduced
libbpf_bpf_attach_type_str function instead of maintaining its own
string representation for the bpf_attach_type enum.

Note that contrary to other enum types, the variant names that bpftool
maps bpf_attach_type to do not adhere a simple to follow rule. With
bpf_prog_type, for example, the textual representation can easily be
inferred by stripping the BPF_PROG_TYPE_ prefix and lowercasing the
remaining string. bpf_attach_type violates this rule for various
variants.
We decided to fix up this deficiency with this change, meaning that
bpftool uses the same textual representations as libbpf. Supporting
tests, completion scripts, and man pages have been adjusted accordingly.
However, we did add support for accepting (the now undocumented)
original attach type names when they are provided by users.

For the test (test_bpftool_synctypes.py), I have removed the enum
representation checks, because we no longer mirror the various enum
variant names in bpftool source code. For the man page, help text, and
completion script checks we are now using enum definitions from
uapi/linux/bpf.h as the source of truth directly.

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220523230428.3077108-10-deso@posteo.net
2022-06-02 16:26:30 -07:00

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.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
================
bpftool-cgroup
================
-------------------------------------------------------------------------------
tool for inspection and simple manipulation of eBPF progs
-------------------------------------------------------------------------------
:Manual section: 8
.. include:: substitutions.rst
SYNOPSIS
========
**bpftool** [*OPTIONS*] **cgroup** *COMMAND*
*OPTIONS* := { |COMMON_OPTIONS| | { **-f** | **--bpffs** } }
*COMMANDS* :=
{ **show** | **list** | **tree** | **attach** | **detach** | **help** }
CGROUP COMMANDS
===============
| **bpftool** **cgroup** { **show** | **list** } *CGROUP* [**effective**]
| **bpftool** **cgroup tree** [*CGROUP_ROOT*] [**effective**]
| **bpftool** **cgroup attach** *CGROUP* *ATTACH_TYPE* *PROG* [*ATTACH_FLAGS*]
| **bpftool** **cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG*
| **bpftool** **cgroup help**
|
| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }
| *ATTACH_TYPE* := { **cgroup_inet_ingress** | **cgroup_inet_egress** |
| **cgroup_inet_sock_create** | **cgroup_sock_ops** |
| **cgroup_device** | **cgroup_inet4_bind** | **cgroup_inet6_bind** |
| **cgroup_inet4_post_bind** | **cgroup_inet6_post_bind** |
| **cgroup_inet4_connect** | **cgroup_inet6_connect** |
| **cgroup_inet4_getpeername** | **cgroup_inet6_getpeername** |
| **cgroup_inet4_getsockname** | **cgroup_inet6_getsockname** |
| **cgroup_udp4_sendmsg** | **cgroup_udp6_sendmsg** |
| **cgroup_udp4_recvmsg** | **cgroup_udp6_recvmsg** |
| **cgroup_sysctl** | **cgroup_getsockopt** | **cgroup_setsockopt** |
| **cgroup_inet_sock_release** }
| *ATTACH_FLAGS* := { **multi** | **override** }
DESCRIPTION
===========
**bpftool cgroup { show | list }** *CGROUP* [**effective**]
List all programs attached to the cgroup *CGROUP*.
Output will start with program ID followed by attach type,
attach flags and program name.
If **effective** is specified retrieve effective programs that
will execute for events within a cgroup. This includes
inherited along with attached ones.
**bpftool cgroup tree** [*CGROUP_ROOT*] [**effective**]
Iterate over all cgroups in *CGROUP_ROOT* and list all
attached programs. If *CGROUP_ROOT* is not specified,
bpftool uses cgroup v2 mountpoint.
The output is similar to the output of cgroup show/list
commands: it starts with absolute cgroup path, followed by
program ID, attach type, attach flags and program name.
If **effective** is specified retrieve effective programs that
will execute for events within a cgroup. This includes
inherited along with attached ones.
**bpftool cgroup attach** *CGROUP* *ATTACH_TYPE* *PROG* [*ATTACH_FLAGS*]
Attach program *PROG* to the cgroup *CGROUP* with attach type
*ATTACH_TYPE* and optional *ATTACH_FLAGS*.
*ATTACH_FLAGS* can be one of: **override** if a sub-cgroup installs
some bpf program, the program in this cgroup yields to sub-cgroup
program; **multi** if a sub-cgroup installs some bpf program,
that cgroup program gets run in addition to the program in this
cgroup.
Only one program is allowed to be attached to a cgroup with
no attach flags or the **override** flag. Attaching another
program will release old program and attach the new one.
Multiple programs are allowed to be attached to a cgroup with
**multi**. They are executed in FIFO order (those that were
attached first, run first).
Non-default *ATTACH_FLAGS* are supported by kernel version 4.14
and later.
*ATTACH_TYPE* can be on of:
**ingress** ingress path of the inet socket (since 4.10);
**egress** egress path of the inet socket (since 4.10);
**sock_create** opening of an inet socket (since 4.10);
**sock_ops** various socket operations (since 4.12);
**device** device access (since 4.15);
**bind4** call to bind(2) for an inet4 socket (since 4.17);
**bind6** call to bind(2) for an inet6 socket (since 4.17);
**post_bind4** return from bind(2) for an inet4 socket (since 4.17);
**post_bind6** return from bind(2) for an inet6 socket (since 4.17);
**connect4** call to connect(2) for an inet4 socket (since 4.17);
**connect6** call to connect(2) for an inet6 socket (since 4.17);
**sendmsg4** call to sendto(2), sendmsg(2), sendmmsg(2) for an
unconnected udp4 socket (since 4.18);
**sendmsg6** call to sendto(2), sendmsg(2), sendmmsg(2) for an
unconnected udp6 socket (since 4.18);
**recvmsg4** call to recvfrom(2), recvmsg(2), recvmmsg(2) for
an unconnected udp4 socket (since 5.2);
**recvmsg6** call to recvfrom(2), recvmsg(2), recvmmsg(2) for
an unconnected udp6 socket (since 5.2);
**sysctl** sysctl access (since 5.2);
**getsockopt** call to getsockopt (since 5.3);
**setsockopt** call to setsockopt (since 5.3);
**getpeername4** call to getpeername(2) for an inet4 socket (since 5.8);
**getpeername6** call to getpeername(2) for an inet6 socket (since 5.8);
**getsockname4** call to getsockname(2) for an inet4 socket (since 5.8);
**getsockname6** call to getsockname(2) for an inet6 socket (since 5.8).
**sock_release** closing an userspace inet socket (since 5.9).
**bpftool cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG*
Detach *PROG* from the cgroup *CGROUP* and attach type
*ATTACH_TYPE*.
**bpftool prog help**
Print short help message.
OPTIONS
=======
.. include:: common_options.rst
-f, --bpffs
Show file names of pinned programs.
EXAMPLES
========
|
| **# mount -t bpf none /sys/fs/bpf/**
| **# mkdir /sys/fs/cgroup/test.slice**
| **# bpftool prog load ./device_cgroup.o /sys/fs/bpf/prog**
| **# bpftool cgroup attach /sys/fs/cgroup/test.slice/ device id 1 allow_multi**
**# bpftool cgroup list /sys/fs/cgroup/test.slice/**
::
ID AttachType AttachFlags Name
1 device allow_multi bpf_prog1
|
| **# bpftool cgroup detach /sys/fs/cgroup/test.slice/ device id 1**
| **# bpftool cgroup list /sys/fs/cgroup/test.slice/**
::
ID AttachType AttachFlags Name