Make bpftool aware and add the new get{peer,sock}name attach types to its
cli, documentation and bash completion to allow attachment/detachment of
sock_addr programs there.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/9765b3d03e4c29210c4df56a9cc7e52f5f7bb5ef.1589841594.git.daniel@iogearbox.net
Bring minor improvements to bpftool documentation. Fix or harmonise
formatting, update map types (including in interactive help), improve
description for "map create", fix a build warning due to a missing line
after the double-colon for the "bpftool prog profile" example,
complete/harmonise/sort the list of related bpftool man pages in
footers.
v2:
- Remove (instead of changing) mark-up on "value" in bpftool-map.rst,
when it does not refer to something passed on the command line.
- Fix an additional typo ("hexadeximal") in the same file.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200511161536.29853-3-quentin@isovalent.com
Currently, only one command is supported
bpftool iter pin <bpf_prog.o> <path>
It will pin the trace/iter bpf program in
the object file <bpf_prog.o> to the <path>
where <path> should be on a bpffs mount.
For example,
$ bpftool iter pin ./bpf_iter_ipv6_route.o \
/sys/fs/bpf/my_route
User can then do a `cat` to print out the results:
$ cat /sys/fs/bpf/my_route
fe800000000000000000000000000000 40 00000000000000000000000000000000 ...
00000000000000000000000000000000 00 00000000000000000000000000000000 ...
00000000000000000000000000000001 80 00000000000000000000000000000000 ...
fe800000000000008c0162fffebdfd57 80 00000000000000000000000000000000 ...
ff000000000000000000000000000000 08 00000000000000000000000000000000 ...
00000000000000000000000000000000 00 00000000000000000000000000000000 ...
The implementation for ipv6_route iterator is in one of subsequent
patches.
This patch also added BPF_LINK_TYPE_ITER to link query.
In the future, we may add additional parameters to pin command
by parameterizing the bpf iterator. For example, a map_id or pid
may be added to let bpf program only traverses a single map or task,
similar to kernel seq_file single_open().
We may also add introspection command for targets/iterators by
leveraging the bpf_iter itself.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200509175920.2477247-1-yhs@fb.com
The new libcap dependency is not used for an essential feature of
bpftool, and we could imagine building the tool without checks on
CAP_SYS_ADMIN by disabling probing features as an unprivileged users.
Make it so, in order to avoid a hard dependency on libcap, and to ease
packaging/embedding of bpftool.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200429144506.8999-4-quentin@isovalent.com
There is demand for a way to identify what BPF helper functions are
available to unprivileged users. To do so, allow unprivileged users to
run "bpftool feature probe" to list BPF-related features. This will only
show features accessible to those users, and may not reflect the full
list of features available (to administrators) on the system.
To avoid the case where bpftool is inadvertently run as non-root and
would list only a subset of the features supported by the system when it
would be expected to list all of them, running as unprivileged is gated
behind the "unprivileged" keyword passed to the command line. When used
by a privileged user, this keyword allows to drop the CAP_SYS_ADMIN and
to list the features available to unprivileged users. Note that this
addsd a dependency on libpcap for compiling bpftool.
Note that there is no particular reason why the probes were restricted
to root, other than the fact I did not need them for unprivileged and
did not bother with the additional checks at the time probes were added.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200429144506.8999-3-quentin@isovalent.com
This patch adds struct_ops support to the bpftool.
To recap a bit on the recent bpf_struct_ops feature on the kernel side:
It currently supports "struct tcp_congestion_ops" to be implemented
in bpf. At a high level, bpf_struct_ops is struct_ops map populated
with a number of bpf progs. bpf_struct_ops currently supports the
"struct tcp_congestion_ops". However, the bpf_struct_ops design is
generic enough that other kernel struct ops can be supported in
the future.
Although struct_ops is map+progs at a high lever, there are differences
in details. For example,
1) After registering a struct_ops, the struct_ops is held by the kernel
subsystem (e.g. tcp-cc). Thus, there is no need to pin a
struct_ops map or its progs in order to keep them around.
2) To iterate all struct_ops in a system, it iterates all maps
in type BPF_MAP_TYPE_STRUCT_OPS. BPF_MAP_TYPE_STRUCT_OPS is
the current usual filter. In the future, it may need to
filter by other struct_ops specific properties. e.g. filter by
tcp_congestion_ops or other kernel subsystem ops in the future.
3) struct_ops requires the running kernel having BTF info. That allows
more flexibility in handling other kernel structs. e.g. it can
always dump the latest bpf_map_info.
4) Also, "struct_ops" command is not intended to repeat all features
already provided by "map" or "prog". For example, if there really
is a need to pin the struct_ops map, the user can use the "map" cmd
to do that.
While the first attempt was to reuse parts from map/prog.c, it ended up
not a lot to share. The only obvious item is the map_parse_fds() but
that still requires modifications to accommodate struct_ops map specific
filtering (for the immediate and the future needs). Together with the
earlier mentioned differences, it is better to part away from map/prog.c.
The initial set of subcmds are, register, unregister, show, and dump.
For register, it registers all struct_ops maps that can be found in an
obj file. Option can be added in the future to specify a particular
struct_ops map. Also, the common bpf_tcp_cc is stateless (e.g.
bpf_cubic.c and bpf_dctcp.c). The "reuse map" feature is not
implemented in this patch and it can be considered later also.
For other subcmds, please see the man doc for details.
A sample output of dump:
[root@arch-fb-vm1 bpf]# bpftool struct_ops dump name cubic
[{
"bpf_map_info": {
"type": 26,
"id": 64,
"key_size": 4,
"value_size": 256,
"max_entries": 1,
"map_flags": 0,
"name": "cubic",
"ifindex": 0,
"btf_vmlinux_value_type_id": 18452,
"netns_dev": 0,
"netns_ino": 0,
"btf_id": 52,
"btf_key_type_id": 0,
"btf_value_type_id": 0
}
},{
"bpf_struct_ops_tcp_congestion_ops": {
"refcnt": {
"refs": {
"counter": 1
}
},
"state": "BPF_STRUCT_OPS_STATE_INUSE",
"data": {
"list": {
"next": 0,
"prev": 0
},
"key": 0,
"flags": 0,
"init": "void (struct sock *) bictcp_init/prog_id:138",
"release": "void (struct sock *) 0",
"ssthresh": "u32 (struct sock *) bictcp_recalc_ssthresh/prog_id:141",
"cong_avoid": "void (struct sock *, u32, u32) bictcp_cong_avoid/prog_id:140",
"set_state": "void (struct sock *, u8) bictcp_state/prog_id:142",
"cwnd_event": "void (struct sock *, enum tcp_ca_event) bictcp_cwnd_event/prog_id:139",
"in_ack_event": "void (struct sock *, u32) 0",
"undo_cwnd": "u32 (struct sock *) tcp_reno_undo_cwnd/prog_id:144",
"pkts_acked": "void (struct sock *, const struct ack_sample *) bictcp_acked/prog_id:143",
"min_tso_segs": "u32 (struct sock *) 0",
"sndbuf_expand": "u32 (struct sock *) 0",
"cong_control": "void (struct sock *, const struct rate_sample *) 0",
"get_info": "size_t (struct sock *, u32, int *, union tcp_cc_info *) 0",
"name": "bpf_cubic",
"owner": 0
}
}
}
]
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200318171656.129650-1-kafai@fb.com
Update documentation of "bpftool feature" command with information about
new arguments: "full".
Signed-off-by: Michal Rostecki <mrostecki@opensuse.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200226165941.6379-4-mrostecki@opensuse.org
Fix bpftool to include libbpf header files with the bpf/ prefix, to be
consistent with external users of the library. Also ensure that all
includes of exported libbpf header files (those that are exported on 'make
install' of the library) use bracketed includes instead of quoted.
To make sure no new files are introduced that doesn't include the bpf/
prefix in its include, remove tools/lib/bpf from the include path entirely,
and use tools/lib instead.
Fixes: 6910d7d386 ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157952560684.1683545.4765181397974997027.stgit@toke.dk
Work-around what appears to be a bug in rst2man convertion tool, used to
create man pages out of reStructureText-formatted documents. If text line
starts with dot, rst2man will put it in resulting man file verbatim. This
seems to cause man tool to interpret it as a directive/command (e.g., `.bs`), and
subsequently not render entire line because it's unrecognized one.
Enclose '.xxx' words in extra formatting to work around.
Fixes: cb21ac5885 ("bpftool: Add gen subcommand manpage")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com
Link: https://lore.kernel.org/bpf/20191218221707.2552199-1-andriin@fb.com
Add bpftool-gen.rst describing skeleton on the high level. Also include
a small, but complete, example BPF app (BPF side, userspace side, generated
skeleton) in example section to demonstrate skeleton API and its usage.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191218052552.2915188-4-andriin@fb.com
This patch implements lookup by name for maps and changes the behavior of
lookups by tag to be consistent with prog subcommands. Similarly to
program subcommands, the show and dump commands will return all maps with
the given name (or tag), whereas other commands will error out if several
maps have the same name (resp. tag).
When a map has BTF info, it is dumped in JSON with available BTF info.
This patch requires that all matched maps have BTF info before switching
the output format to JSON.
Signed-off-by: Paul Chaignon <paul.chaignon@orange.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/8de1c9f273860b3ea1680502928f4da2336b853e.1576263640.git.paul.chaignon@gmail.com
When working with frequently modified BPF programs, both the ID and the
tag may change. bpftool currently doesn't provide a "stable" way to match
such programs.
This patch implements lookup by name for programs. The show and dump
commands will return all programs with the given name, whereas other
commands will error out if several programs have the same name.
Signed-off-by: Paul Chaignon <paul.chaignon@orange.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Link: https://lore.kernel.org/bpf/b5fc1a5dcfaeb5f16fc80295cdaa606dd2d91534.1576263640.git.paul.chaignon@gmail.com
When several BPF programs have the same tag, bpftool matches only the
first (in ID order). This patch changes that behavior such that dump and
show commands return all matched programs. Commands that require a single
program (e.g., pin and attach) will error out if given a tag that matches
several. bpftool prog dump will also error out if file or visual are
given and several programs have the given tag.
In the case of the dump command, a program header is added before each
dump only if the tag matches several programs; this patch doesn't change
the output if a single program matches. The output when several
programs match thus looks as follows.
$ ./bpftool prog dump xlated tag 6deef7357e7b4530
3: cgroup_skb tag 6deef7357e7b4530 gpl
0: (bf) r6 = r1
[...]
7: (95) exit
4: cgroup_skb tag 6deef7357e7b4530 gpl
0: (bf) r6 = r1
[...]
7: (95) exit
Signed-off-by: Paul Chaignon <paul.chaignon@orange.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/fb1fe943202659a69cd21dd5b907c205af1e1e22.1576263640.git.paul.chaignon@gmail.com
Add a new subcommand to freeze maps from user space.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add a "btf list" (alias: "btf show") subcommand to bpftool in order to
dump all BTF objects loaded on a system.
When running the command, hash tables are built in bpftool to retrieve
all the associations between BTF objects and BPF maps and programs. This
allows for printing all such associations when listing the BTF objects.
The command is added at the top of the subcommands for "bpftool btf", so
that typing only "bpftool btf" also comes down to listing the programs.
We could not have this with the previous command ("dump"), which
required a BTF object id, so it should not break any previous behaviour.
This also makes the "btf" command behaviour consistent with "prog" or
"map".
Bash completion is updated to use "bpftool btf" instead of "bpftool
prog" to list the BTF ids, as it looks more consistent.
Example output (plain):
# bpftool btf show
9: size 2989B prog_ids 21 map_ids 15
17: size 2847B prog_ids 36 map_ids 30,29,28
26: size 2847B
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Since, new sub-command 'net attach/detach' has been added for
attaching XDP program on interface,
this commit documents usage and sample output of `net attach/detach`.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Takshak said in the original submission:
With different bpf attach_flags available to attach bpf programs specially
with BPF_F_ALLOW_OVERRIDE and BPF_F_ALLOW_MULTI, the list of effective
bpf-programs available to any sub-cgroups really needs to be available for
easy debugging.
Using BPF_F_QUERY_EFFECTIVE flag, one can get the list of not only attached
bpf-programs to a cgroup but also the inherited ones from parent cgroup.
So a new option is introduced to use BPF_F_QUERY_EFFECTIVE query flag here
to list all the effective bpf-programs available for execution at a specified
cgroup.
Reused modified test program test_cgroup_attach from tools/testing/selftests/bpf:
# ./test_cgroup_attach
With old bpftool:
# bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/
ID AttachType AttachFlags Name
271 egress multi pkt_cntr_1
272 egress multi pkt_cntr_2
Attached new program pkt_cntr_4 in cg2 gives following:
# bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/cg2
ID AttachType AttachFlags Name
273 egress override pkt_cntr_4
And with new "effective" option it shows all effective programs for cg2:
# bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/cg2 effective
ID AttachType AttachFlags Name
273 egress override pkt_cntr_4
271 egress override pkt_cntr_1
272 egress override pkt_cntr_2
Compared to original submission use a local flag instead of global
option.
We need to clear query_flags on every command, in case batch mode
wants to use varying settings.
v2: (Takshak)
- forbid duplicated flags;
- fix cgroup path freeing.
Signed-off-by: Takshak Chahande <ctakshak@fb.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Takshak Chahande <ctakshak@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a new "bpftool prog run" subcommand to run a loaded program on input
data (and possibly with input context) passed by the user.
Print output data (and output context if relevant) into a file or into
the console. Print return value and duration for the test run into the
console.
A "repeat" argument can be passed to run the program several times in a
row.
The command does not perform any kind of verification based on program
type (Is this program type allowed to use an input context?) or on data
consistency (Can I work with empty input data?), this is left to the
kernel.
Example invocation:
# perl -e 'print "\x0" x 14' | ./bpftool prog run \
pinned /sys/fs/bpf/sample_ret0 \
data_in - data_out - repeat 5
0000000 0000 0000 0000 0000 0000 0000 0000 | ........ ......
Return value: 0, duration (average): 260ns
When one of data_in or ctx_in is "-", bpftool reads from standard input,
in binary format. Other formats (JSON, hexdump) might be supported (via
an optional command line keyword like "data_fmt_in") in the future if
relevant, but this would require doing more parsing in bpftool.
v2:
- Fix argument names for function check_single_stdin(). (Yonghong)
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Support sockopt prog type and cgroup hooks in the bpftool.
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf 2019-06-07
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix several bugs in riscv64 JIT code emission which forgot to clear high
32-bits for alu32 ops, from Björn and Luke with selftests covering all
relevant BPF alu ops from Björn and Jiong.
2) Two fixes for UDP BPF reuseport that avoid calling the program in case of
__udp6_lib_err and UDP GRO which broke reuseport_select_sock() assumption
that skb->data is pointing to transport header, from Martin.
3) Two fixes for BPF sockmap: a use-after-free from sleep in psock's backlog
workqueue, and a missing restore of sk_write_space when psock gets dropped,
from Jakub and John.
4) Fix unconnected UDP sendmsg hook API which is insufficient as-is since it
breaks standard applications like DNS if reverse NAT is not performed upon
receive, from Daniel.
5) Fix an out-of-bounds read in __bpf_skc_lookup which in case of AF_INET6
fails to verify that the length of the tuple is long enough, from Lorenz.
6) Fix libbpf's libbpf__probe_raw_btf to return an fd instead of 0/1 (for
{un,}successful probe) as that is expected to be propagated as an fd to
load_sk_storage_btf() and thus closing the wrong descriptor otherwise,
from Michal.
7) Fix bpftool's JSON output for the case when a lookup fails, from Krzesimir.
8) Minor misc fixes in docs, samples and selftests, from various others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Trivial patch to bpftool in order to complete enabling attaching programs
to BPF_CGROUP_UDP{4,6}_RECVMSG.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The "-d" option is used to require all logs available for bpftool. So
far it meant telling libbpf to print even debug-level information. But
there is another source of info that can be made more verbose: when we
attemt to load programs with bpftool, we can pass a log_level parameter
to the verifier in order to control the amount of information that is
printed to the console.
Reuse the "-d" option to print all information the verifier can tell. At
this time, this means logs related to BPF_LOG_LEVEL1, BPF_LOG_LEVEL2 and
BPF_LOG_STATS. As mentioned in the discussion on the first version of
this set, these macros are internal to the kernel
(include/linux/bpf_verifier.h) and are not meant to be part of the
stable user API, therefore we simply use the related constants to print
whatever we can at this time, without trying to tell users what is
log_level1 or what is statistics.
Verifier logs are only used when loading programs for now (In the
future: for loading BTF objects with bpftool? Although libbpf does not
currently offer to print verifier info at debug level if no error
occurred when loading BTF objects), so bpftool.rst and bpftool-prog.rst
are the only man pages to get the update.
v3:
- Add details on log level and BTF loading at the end of commit log.
v2:
- Remove the possibility to select the log levels to use (v1 offered a
combination of "log_level1", "log_level2" and "stats").
- The macros from kernel header bpf_verifier.h are not used (and
therefore not moved to UAPI header).
- In v1 this was a distinct option, but is now merged in the only "-d"
switch to activate libbpf and verifier debug-level logs all at the
same time.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
libbpf has three levels of priority for output messages: warn, info,
debug. By default, debug output is not printed to the console.
Add a new "--debug" (short name: "-d") option to bpftool to print libbpf
logs for all three levels.
Internally, we simply use the function provided by libbpf to replace the
default printing function by one that prints logs regardless of their
level.
v2:
- Remove the possibility to select the log-levels to use (v1 offered a
combination of "warn", "info" and "debug").
- Rename option and offer a short name: -d|--debug.
- Add option description to all bpftool manual pages (instead of
bpftool-prog.rst only), as all commands use libbpf.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Document usage and sample output format for `btf dump` sub-command.
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add support for recently added BPF_PROG_TYPE_CGROUP_SYSCTL program type
and BPF_CGROUP_SYSCTL attach type.
Example of bpftool output with sysctl program from selftests:
# bpftool p load ./test_sysctl_prog.o /mnt/bpf/sysctl_prog type cgroup/sysctl
# bpftool p l
9: cgroup_sysctl name sysctl_tcp_mem tag 0dd05f81a8d0d52e gpl
loaded_at 2019-04-16T12:57:27-0700 uid 0
xlated 1008B jited 623B memlock 4096B
# bpftool c a /mnt/cgroup2/bla sysctl id 9
# bpftool c t
CgroupPath
ID AttachType AttachFlags Name
/mnt/cgroup2/bla
9 sysctl sysctl_tcp_mem
# bpftool c d /mnt/cgroup2/bla sysctl id 9
# bpftool c t
CgroupPath
ID AttachType AttachFlags Name
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Linux kernel now supports statistics for BPF programs, and bpftool is
able to dump them. However, these statistics are not enabled by default,
and administrators may not know how to access them.
Add a paragraph in bpftool documentation, under the description of the
"bpftool prog show" command, to explain that such statistics are
available and that their collection is controlled via a dedicated sysctl
knob.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Manual pages would tell that option "-v" (lower case) would print the
version number for bpftool. This is wrong: the short name of the option
is "-V" (upper case). Fix the documentation accordingly.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The "pinmaps" keyword is present in the man page, in the verbose
description of the "bpftool prog load" command. However, it is missing
from the summary of available commands at the beginning of the file. Add
it there as well.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
bpftool has support for attach types "stream_verdict" and
"stream_parser" but the documentation was referring to them as
"skb_verdict" and "skb_parse". The inconsistency comes from commit
b7d3826c2e ("bpf: bpftool, add support for attaching programs to
maps").
This patch changes the documentation to match the implementation:
- "bpftool prog help"
- man pages
- bash completion
Signed-off-by: Alban Crequy <alban@kinvolk.io>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch adds missing information about feature-subcommand in
bpftool.rst
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
bpftool gained support for probing the current system in order to see
what program and map types, and what helpers are available on that
system. This patch adds the possibility to pass an interface index to
libbpf (and hence to the kernel) when trying to load the programs or to
create the maps, in order to see what items a given network device can
support.
A new keyword "dev <ifname>" can be used as an alternative to "kernel"
to indicate that the given device should be tested. If no target ("dev"
or "kernel") is specified bpftool defaults to probing the kernel.
Sample output:
# bpftool -p feature probe dev lo
{
"syscall_config": {
"have_bpf_syscall": true
},
"program_types": {
"have_sched_cls_prog_type": false,
"have_xdp_prog_type": false
},
...
}
As the target is a network device, /proc/ parameters and kernel
configuration are NOT dumped. Availability of the bpf() syscall is
still probed, so we can return early if that syscall is not usable
(since there is no point in attempting the remaining probes in this
case).
Among the program types, only the ones that can be offloaded are probed.
All map types are probed, as there is no specific rule telling which one
could or could not be supported by a device in the future. All helpers
are probed (but only for offload-able program types).
Caveat: as bpftool does not attempt to attach programs to the device at
the moment, probes do not entirely reflect what the device accepts:
typically, for Netronome's nfp, results will announce that TC cls
offload is available even if support has been deactivated (with e.g.
ethtool -K eth1 hw-tc-offload off).
v2:
- All helpers are probed, whereas previous version would only probe the
ones compatible with an offload-able program type. This is because we
do not keep a default compatible program type for each helper anymore.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make bpftool able to dump a subset of the parameters collected by
probing the system as a listing of C-style #define macros, so that
external projects can reuse the result of this probing and build
BPF-based project in accordance with the features available on the
system.
The new "macros" keyword is used to select this output. An additional
"prefix" keyword is added so that users can select a custom prefix for
macro names, in order to avoid any namespace conflict.
Sample output:
# bpftool feature probe kernel macros prefix FOO_
/*** System call availability ***/
#define FOO_HAVE_BPF_SYSCALL
/*** eBPF program types ***/
#define FOO_HAVE_SOCKET_FILTER_PROG_TYPE
#define FOO_HAVE_KPROBE_PROG_TYPE
#define FOO_HAVE_SCHED_CLS_PROG_TYPE
...
/*** eBPF map types ***/
#define FOO_HAVE_HASH_MAP_TYPE
#define FOO_HAVE_ARRAY_MAP_TYPE
#define FOO_HAVE_PROG_ARRAY_MAP_TYPE
...
/*** eBPF helper functions ***/
/*
* Use FOO_HAVE_PROG_TYPE_HELPER(prog_type_name, helper_name)
* to determine if <helper_name> is available for <prog_type_name>,
* e.g.
* #if FOO_HAVE_PROG_TYPE_HELPER(xdp, bpf_redirect)
* // do stuff with this helper
* #elif
* // use a workaround
* #endif
*/
#define FOO_HAVE_PROG_TYPE_HELPER(prog_type, helper) \
FOO_BPF__PROG_TYPE_ ## prog_type ## __HELPER_ ## helper
...
#define FOO_BPF__PROG_TYPE_socket_filter__HELPER_bpf_probe_read 0
#define FOO_BPF__PROG_TYPE_socket_filter__HELPER_bpf_ktime_get_ns 1
#define FOO_BPF__PROG_TYPE_socket_filter__HELPER_bpf_trace_printk 1
...
v3:
- Change output for helpers again: add a
HAVE_PROG_TYPE_HELPER(type, helper) macro that can be used to tell
if <helper> is available for program <type>.
v2:
- #define-based output added as a distinct patch.
- "HAVE_" prefix appended to macro names.
- Output limited to bpf() syscall availability, BPF prog and map types,
helper functions. In this version kernel config options, procfs
parameter or kernel version are intentionally left aside.
- Following the change on helper probes, format for helper probes in
this output style has changed (now a list of compatible program
types).
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Similarly to what was done for program types and map types, add a set of
probes to test the availability of the different eBPF helper functions
on the current system.
For each known program type, all known helpers are tested, in order to
establish a compatibility matrix. Output is provided as a set of lists
of available helpers, one per program type.
Sample output:
# bpftool feature probe kernel
...
Scanning eBPF helper functions...
eBPF helpers supported for program type socket_filter:
- bpf_map_lookup_elem
- bpf_map_update_elem
- bpf_map_delete_elem
...
eBPF helpers supported for program type kprobe:
- bpf_map_lookup_elem
- bpf_map_update_elem
- bpf_map_delete_elem
...
# bpftool --json --pretty feature probe kernel
{
...
"helpers": {
"socket_filter_available_helpers": ["bpf_map_lookup_elem", \
"bpf_map_update_elem","bpf_map_delete_elem", ...
],
"kprobe_available_helpers": ["bpf_map_lookup_elem", \
"bpf_map_update_elem","bpf_map_delete_elem", ...
],
...
}
}
v5:
- In libbpf.map, move global symbol to the new LIBBPF_0.0.2 section.
v4:
- Use "enum bpf_func_id" instead of "__u32" in bpf_probe_helper()
declaration for the type of the argument used to pass the id of
the helper to probe.
- Undef BPF_HELPER_MAKE_ENTRY after using it.
v3:
- Do not pass kernel version from bpftool to libbpf probes (kernel
version for testing program with kprobes is retrieved directly from
libbpf).
- Dump one list of available helpers per program type (instead of one
list of compatible program types per helper).
v2:
- Move probes from bpftool to libbpf.
- Test all program types for each helper, print a list of working prog
types for each helper.
- Fall back on include/uapi/linux/bpf.h for names and ids of helpers.
- Remove C-style macros output from this patch.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a new component and command for bpftool, in order to probe the
system to dump a set of eBPF-related parameters so that users can know
what features are available on the system.
Parameters are dumped in plain or JSON output (with -j/-p options).
The current patch introduces probing of one simple parameter:
availability of the bpf() system call. Later commits
will add other probes.
Sample output:
# bpftool feature probe kernel
Scanning system call availability...
bpf() syscall is available
# bpftool --json --pretty feature probe kernel
{
"syscall_config": {
"have_bpf_syscall": true
}
}
The optional "kernel" keyword enforces probing of the current system,
which is the only possible behaviour at this stage. It can be safely
omitted.
The feature comes with the relevant man page, but bash completion will
come in a dedicated commit.
v3:
- Do not probe kernel version. Contrarily to what is written below for
v2, we can have the kernel version retrieved in libbpf instead of
bpftool (in the patch adding probing for program types).
v2:
- Remove C-style macros output from this patch.
- Even though kernel version is no longer needed for testing kprobes
availability, note that we still collect it in this patch so that
bpftool gets able to probe (in next patches) older kernels as well.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This is intended to be used with queues and stacks, it pops and prints
the last element via bpf_map_lookup_and_delete_elem.
Example:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map push pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map pop pinned /sys/fs/bpf/q
value: 00 01 02 03
bpftool map pop pinned /sys/fs/bpf/q
Error: empty map
bpftool map create /sys/fs/bpf/s type stack value 4 entries 10 name s
bpftool map enqueue pinned /sys/fs/bpf/s value 0 1 2 3
bpftool map dequeue pinned /sys/fs/bpf/s
value: 00 01 02 03
bpftool map dequeue pinned /sys/fs/bpf/s
Error: empty map
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This is intended to be used with queues and stacks and be more
user-friendly than 'update' without the key.
Example:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map push pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map peek pinned /sys/fs/bpf/q
value: 00 01 02 03
bpftool map create /sys/fs/bpf/s type stack value 4 entries 10 name s
bpftool map enqueue pinned /sys/fs/bpf/s value 0 1 2 3
bpftool map peek pinned /sys/fs/bpf/s
value: 00 01 02 03
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This is intended to be used with queues and stacks and be more
user-friendly than 'lookup' without key/value.
Example:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map peek pinned /sys/fs/bpf/q
value: 00 01 02 03
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Bpftool expects key for 'lookup' operations. For some map types, key should
not be specified. Support looking up those map types.
Before:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map lookup pinned /sys/fs/bpf/q
Error: did not find key
After:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map lookup pinned /sys/fs/bpf/q
key: value: 00 01 02 03
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Bpftool expects both key and value for 'update' operations. For some
map types, key should not be specified. Support updating those map types.
Before:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
Error: did not find key
After:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
In order to make life easier for users, bpftool automatically attempts
to mount the BPF virtual file system, if it is not mounted already,
before trying to pin objects in it. Similarly, it attempts to mount
tracefs if necessary before trying to dump the trace pipe to the
console.
While mounting file systems on-the-fly can improve user experience, some
administrators might prefer to avoid that. Let's add an option to block
these mount attempts. Note that it does not prevent automatic mounting
of tracefs by debugfs for the "bpftool prog tracelog" command.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add an example in map documentation to show how to use bpftool in order
to update the references to programs hold by prog array maps.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
