Граф коммитов

99 Коммитов

Автор SHA1 Сообщение Дата
Ilya Leoshkevich 38f0408ef7 bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd()
Use the new type-safe wrappers around bpf_obj_get_info_by_fd().

Split the bpf_obj_get_info_by_fd() call in build_btf_type_table() in
two, since knowing the type helps with the Memory Sanitizer.

Improve map_parse_fd_and_info() type safety by using
struct bpf_map_info * instead of void * for info.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20230214231221.249277-4-iii@linux.ibm.com
2023-02-16 15:32:45 -08:00
Sahid Orentino Ferdjaoui 9b81075534 bpftool: remove support of --legacy option for bpftool
Following:
  commit bd054102a8 ("libbpf: enforce strict libbpf 1.0 behaviors")
  commit 93b8952d22 ("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 <sahid.ferdjaoui@industrialdiscipline.com>
Acked-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20221120112515.38165-2-sahid.ferdjaoui@industrialdiscipline.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20 16:17:46 -08:00
Eduard Zingerman c302378bc1 libbpf: Hashmap interface update to allow both long and void* keys/values
An update for libbpf's hashmap interface from void* -> void* to a
polymorphic one, allowing both long and void* keys and values.

This simplifies many use cases in libbpf as hashmaps there are mostly
integer to integer.

Perf copies hashmap implementation from libbpf and has to be
updated as well.

Changes to libbpf, selftests/bpf and perf are packed as a single
commit to avoid compilation issues with any future bisect.

Polymorphic interface is acheived by hiding hashmap interface
functions behind auxiliary macros that take care of necessary
type casts, for example:

    #define hashmap_cast_ptr(p)						\
	({								\
		_Static_assert((p) == NULL || sizeof(*(p)) == sizeof(long),\
			       #p " pointee should be a long-sized integer or a pointer"); \
		(long *)(p);						\
	})

    bool hashmap_find(const struct hashmap *map, long key, long *value);

    #define hashmap__find(map, key, value) \
		hashmap_find((map), (long)(key), hashmap_cast_ptr(value))

- hashmap__find macro casts key and value parameters to long
  and long* respectively
- hashmap_cast_ptr ensures that value pointer points to a memory
  of appropriate size.

This hack was suggested by Andrii Nakryiko in [1].
This is a follow up for [2].

[1] https://lore.kernel.org/bpf/CAEf4BzZ8KFneEJxFAaNCCFPGqp20hSpS2aCj76uRk3-qZUH5xg@mail.gmail.com/
[2] https://lore.kernel.org/bpf/af1facf9-7bc8-8a3d-0db4-7b3f333589a2@meta.com/T/#m65b28f1d6d969fcd318b556db6a3ad499a42607d

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221109142611.879983-2-eddyz87@gmail.com
2022-11-09 20:45:14 -08:00
Quentin Monnet ce4f660862 bpftool: Support setting alternative arch for JIT disasm with LLVM
For offloaded BPF programs, instead of failing to create the
LLVM disassembler without even looking for a triple at all, do run the
function that attempts to retrieve a valid architecture name for the
device.

It will still fail for the LLVM disassembler, because currently we have
no valid triple to return (NFP disassembly is not supported by LLVM).
But failing in that function is more logical than to assume in
jit_disasm.c that passing an "arch" name is simply not supported.

Suggested-by: Song Liu <song@kernel.org>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20221025150329.97371-8-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-25 10:11:56 -07:00
Quentin Monnet eb9d1acf63 bpftool: Add LLVM as default library for disassembling JIT-ed programs
To disassemble instructions for JIT-ed programs, bpftool has relied on
the libbfd library. This has been problematic in the past: libbfd's
interface is not meant to be stable and has changed several times. For
building bpftool, we have to detect how the libbfd version on the system
behaves, which is why we have to handle features disassembler-four-args
and disassembler-init-styled in the Makefile. When it comes to shipping
bpftool, this has also caused issues with several distribution
maintainers unwilling to support the feature (see for example Debian's
page for binutils-dev, which ships libbfd: "Note that building Debian
packages which depend on the shared libbfd is Not Allowed." [0]).

For these reasons, we add support for LLVM as an alternative to libbfd
for disassembling instructions of JIT-ed programs. Thanks to the
preparation work in the previous commits, it's easy to add the library
by passing the relevant compilation options in the Makefile, and by
adding the functions for setting up the LLVM disassembler in file
jit_disasm.c.

The LLVM disassembler requires the LLVM development package (usually
llvm-dev or llvm-devel).

The expectation is that the interface for this disassembler will be more
stable. There is a note in LLVM's Developer Policy [1] stating that the
stability for the C API is "best effort" and not guaranteed, but at
least there is some effort to keep compatibility when possible (which
hasn't really been the case for libbfd so far). Furthermore, the Debian
page for the related LLVM package does not caution against linking to
the lib, as binutils-dev page does.

Naturally, the display of disassembled instructions comes with a few
minor differences. Here is a sample output with libbfd (already
supported before this patch):

    # bpftool prog dump jited id 56
    bpf_prog_6deef7357e7b4530:
       0:   nopl   0x0(%rax,%rax,1)
       5:   xchg   %ax,%ax
       7:   push   %rbp
       8:   mov    %rsp,%rbp
       b:   push   %rbx
       c:   push   %r13
       e:   push   %r14
      10:   mov    %rdi,%rbx
      13:   movzwq 0xb4(%rbx),%r13
      1b:   xor    %r14d,%r14d
      1e:   or     $0x2,%r14d
      22:   mov    $0x1,%eax
      27:   cmp    $0x2,%r14
      2b:   jne    0x000000000000002f
      2d:   xor    %eax,%eax
      2f:   pop    %r14
      31:   pop    %r13
      33:   pop    %rbx
      34:   leave
      35:   ret

LLVM supports several variants that we could set when initialising the
disassembler, for example with:

    LLVMSetDisasmOptions(*ctx,
                         LLVMDisassembler_Option_AsmPrinterVariant);

but the default printer is used for now. Here is the output with LLVM:

    # bpftool prog dump jited id 56
    bpf_prog_6deef7357e7b4530:
       0:   nopl    (%rax,%rax)
       5:   nop
       7:   pushq   %rbp
       8:   movq    %rsp, %rbp
       b:   pushq   %rbx
       c:   pushq   %r13
       e:   pushq   %r14
      10:   movq    %rdi, %rbx
      13:   movzwq  180(%rbx), %r13
      1b:   xorl    %r14d, %r14d
      1e:   orl     $2, %r14d
      22:   movl    $1, %eax
      27:   cmpq    $2, %r14
      2b:   jne     0x2f
      2d:   xorl    %eax, %eax
      2f:   popq    %r14
      31:   popq    %r13
      33:   popq    %rbx
      34:   leave
      35:   retq

The LLVM disassembler comes as the default choice, with libbfd as a
fall-back.

Of course, we could replace libbfd entirely and avoid supporting two
different libraries. One reason for keeping libbfd is that, right now,
it works well, we have all we need in terms of features detection in the
Makefile, so it provides a fallback for disassembling JIT-ed programs if
libbfd is installed but LLVM is not. The other motivation is that libbfd
supports nfp instruction for Netronome's SmartNICs and can be used to
disassemble offloaded programs, something that LLVM cannot do. If
libbfd's interface breaks again in the future, we might reconsider
keeping support for it.

[0] https://packages.debian.org/buster/binutils-dev
[1] https://llvm.org/docs/DeveloperPolicy.html#c-api-changes

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221025150329.97371-7-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-25 10:11:56 -07:00
Quentin Monnet 55b4de58d0 bpftool: Remove asserts from JIT disassembler
The JIT disassembler in bpftool is the only components (with the JSON
writer) using asserts to check the return values of functions. But it
does not do so in a consistent way, and diasm_print_insn() returns no
value, although sometimes the operation failed.

Remove the asserts, and instead check the return values, print messages
on errors, and propagate the error to the caller from prog.c.

Remove the inclusion of assert.h from jit_disasm.c, and also from map.c
where it is unused.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20221025150329.97371-3-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-25 10:11:56 -07:00
Tobias Klauser b0cbd6154a bpftool: Remove attach_type_name forward declaration
The attach_type_name definition was removed in commit 1ba5ad36e0
("bpftool: Use libbpf_bpf_attach_type_str"). Remove its forward
declaration in main.h as well.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220630093638.25916-1-tklauser@distanz.ch
2022-06-30 16:11:20 +02:00
Quentin Monnet 6b4384ff10 Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"
This reverts commit a777e18f1b.

In commit a777e18f1b ("bpftool: Use libbpf 1.0 API mode instead of
RLIMIT_MEMLOCK"), we removed the rlimit bump in bpftool, because the
kernel has switched to memcg-based memory accounting. Thanks to the
LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK, we attempted to keep compatibility
with other systems and ask libbpf to raise the limit for us if
necessary.

How do we know if memcg-based accounting is supported? There is a probe
in libbpf to check this. But this probe currently relies on the
availability of a given BPF helper, bpf_ktime_get_coarse_ns(), which
landed in the same kernel version as the memory accounting change. This
works in the generic case, but it may fail, for example, if the helper
function has been backported to an older kernel. This has been observed
for Google Cloud's Container-Optimized OS (COS), where the helper is
available but rlimit is still in use. The probe succeeds, the rlimit is
not raised, and probing features with bpftool, for example, fails.

A patch was submitted [0] to update this probe in libbpf, based on what
the cilium/ebpf Go library does [1]. It would lower the soft rlimit to
0, attempt to load a BPF object, and reset the rlimit. But it may induce
some hard-to-debug flakiness if another process starts, or the current
application is killed, while the rlimit is reduced, and the approach was
discarded.

As a workaround to ensure that the rlimit bump does not depend on the
availability of a given helper, we restore the unconditional rlimit bump
in bpftool for now.

  [0] https://lore.kernel.org/bpf/20220609143614.97837-1-quentin@isovalent.com/
  [1] https://github.com/cilium/ebpf/blob/v0.9.0/rlimit/rlimit.go#L39

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Yafang Shao <laoar.shao@gmail.com>
Cc: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20220610112648.29695-2-quentin@isovalent.com
2022-06-14 22:18:06 +02:00
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
Daniel Müller 2e98964bd6 bpftool: Use libbpf_bpf_map_type_str
This change switches bpftool over to using the recently introduced
libbpf_bpf_map_type_str function instead of maintaining its own string
representation for the bpf_map_type enum.

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/20220523230428.3077108-7-deso@posteo.net
2022-06-02 16:26:24 -07:00
Daniel Müller b700eeb406 bpftool: Use libbpf_bpf_prog_type_str
This change switches bpftool over to using the recently introduced
libbpf_bpf_prog_type_str function instead of maintaining its own string
representation for the bpf_prog_type enum.

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220523230428.3077108-4-deso@posteo.net
2022-06-02 16:26:18 -07:00
Yafang Shao a777e18f1b bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK
We have switched to memcg-based memory accouting and thus the rlimit is
not needed any more. LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK was introduced in
libbpf for backward compatibility, so we can use it instead now.

libbpf_set_strict_mode always return 0, so we don't need to check whether
the return value is 0 or not.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220409125958.92629-4-laoar.shao@gmail.com
2022-04-10 20:17:16 -07:00
Dmitrii Dolgov cbdaf71f7e bpftool: Add bpf_cookie to link output
Commit 82e6b1eee6 ("bpf: Allow to specify user-provided bpf_cookie for
BPF perf links") introduced the concept of user specified bpf_cookie,
which could be accessed by BPF programs using bpf_get_attach_cookie().
For troubleshooting purposes it is convenient to expose bpf_cookie via
bpftool as well, so there is no need to meddle with the target BPF
program itself.

Implemented using the pid iterator BPF program to actually fetch
bpf_cookies, which allows constraining code changes only to bpftool.

$ bpftool link
1: type 7  prog 5
        bpf_cookie 123
        pids bootstrap(81)

Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220309163112.24141-1-9erthalion6@gmail.com
2022-03-15 15:07:27 -07:00
Mauricio Vásquez a19df71394 bpftool: Remove usage of reallocarray()
This commit fixes a compilation error on systems with glibc < 2.26 [0]:

```
In file included from main.h:14:0,
                 from gen.c:24:
linux/tools/include/tools/libc_compat.h:11:21: error: attempt to use poisoned "reallocarray"
 static inline void *reallocarray(void *ptr, size_t nmemb, size_t size)
```

This happens because gen.c pulls <bpf/libbpf_internal.h>, and then
<tools/libc_compat.h> (through main.h). When
COMPAT_NEED_REALLOCARRAY is set, libc_compat.h defines reallocarray()
which libbpf_internal.h poisons with a GCC pragma.

This commit reuses libbpf_reallocarray() implemented in commit
029258d7b2 ("libbpf: Remove any use of reallocarray() in libbpf").

v1 -> v2:
- reuse libbpf_reallocarray() instead of reimplementing it

Fixes: a9caaba399 ("bpftool: Implement "gen min_core_btf" logic")
Reported-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Mauricio Vásquez <mauricio@kinvolk.io>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220221125617.39610-1-mauricio@kinvolk.io

[0]: https://lore.kernel.org/bpf/3bf2bd49-9f2d-a2df-5536-bc0dde70a83b@isovalent.com/
2022-02-23 13:55:01 -08:00
Raman Shukhau b662000aff bpftool: Adding support for BTF program names
`bpftool prog list` and other bpftool subcommands that show
BPF program names currently get them from bpf_prog_info.name.
That field is limited to 16 (BPF_OBJ_NAME_LEN) chars which leads
to truncated names since many progs have much longer names.

The idea of this change is to improve all bpftool commands that
output prog name so that bpftool uses info from BTF to print
program names if available.

It tries bpf_prog_info.name first and fall back to btf only if
the name is suspected to be truncated (has 15 chars length).

Right now `bpftool p show id <id>` returns capped prog name

<id>: kprobe  name example_cap_cap  tag 712e...
...

With this change it would return

<id>: kprobe  name example_cap_capable  tag 712e...
...

Note, other commands that print prog names (e.g. "bpftool
cgroup tree") are also addressed in this change.

Signed-off-by: Raman Shukhau <ramasha@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220119100255.1068997-1-ramasha@fb.com
2022-01-19 10:04:41 -08:00
Stanislav Fomichev 314f14abde bpftool: Enable libbpf's strict mode by default
Otherwise, attaching with bpftool doesn't work with strict section names.

Also:

  - Add --legacy option to switch back to pre-1.0 behavior
  - Print a warning when program fails to load in strict mode to
    point to --legacy flag
  - By default, don't append / to the section name; in strict
    mode it's relevant only for a small subset of prog types

+ bpftool --legacy prog loadall tools/testing/selftests/bpf/test_cgroup_link.o /sys/fs/bpf/kprobe type kprobe
libbpf: failed to pin program: File exists
Error: failed to pin all programs
+ bpftool prog loadall tools/testing/selftests/bpf/test_cgroup_link.o /sys/fs/bpf/kprobe type kprobe

v1 -> v2:
  - strict by default (Quentin Monnet)
  - add more info to --legacy description (Quentin Monnet)
  - add bash completion (Quentin Monnet)

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20211110192324.920934-1-sdf@google.com
2021-11-12 16:54:58 +01:00
Quentin Monnet d6699f8e0f bpftool: Switch to libbpf's hashmap for PIDs/names references
In order to show PIDs and names for processes holding references to BPF
programs, maps, links, or BTF objects, bpftool creates hash maps to
store all relevant information. This commit is part of a set that
transitions from the kernel's hash map implementation to the one coming
with libbpf.

The motivation is to make bpftool less dependent of kernel headers, to
ease the path to a potential out-of-tree mirror, like libbpf has.

This is the third and final step of the transition, in which we convert
the hash maps used for storing the information about the processes
holding references to BPF objects (programs, maps, links, BTF), and at
last we drop the inclusion of tools/include/linux/hashtable.h.

Note: Checkpatch complains about the use of __weak declarations, and the
missing empty lines after the bunch of empty function declarations when
compiling without the BPF skeletons (none of these were introduced in
this patch). We want to keep things as they are, and the reports should
be safe to ignore.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211023205154.6710-6-quentin@isovalent.com
2021-10-25 17:31:39 -07:00
Quentin Monnet 2828d0d75b bpftool: Switch to libbpf's hashmap for programs/maps in BTF listing
In order to show BPF programs and maps using BTF objects when the latter
are being listed, bpftool creates hash maps to store all relevant items.
This commit is part of a set that transitions from the kernel's hash map
implementation to the one coming with libbpf.

The motivation is to make bpftool less dependent of kernel headers, to
ease the path to a potential out-of-tree mirror, like libbpf has.

This commit focuses on the two hash maps used by bpftool when listing
BTF objects to store references to programs and maps, and convert them
to the libbpf's implementation.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211023205154.6710-5-quentin@isovalent.com
2021-10-25 17:31:39 -07:00
Quentin Monnet 8f184732b6 bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects
In order to show pinned paths for BPF programs, maps, or links when
listing them with the "-f" option, bpftool creates hash maps to store
all relevant paths under the bpffs. So far, it would rely on the
kernel implementation (from tools/include/linux/hashtable.h).

We can make bpftool rely on libbpf's implementation instead. The
motivation is to make bpftool less dependent of kernel headers, to ease
the path to a potential out-of-tree mirror, like libbpf has.

This commit is the first step of the conversion: the hash maps for
pinned paths for programs, maps, and links are converted to libbpf's
hashmap.{c,h}. Other hash maps used for the PIDs of process holding
references to BPF objects are left unchanged for now. On the build side,
this requires adding a dependency to a second header internal to libbpf,
and making it a dependency for the bootstrap bpftool version as well.
The rest of the changes are a rather straightforward conversion.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211023205154.6710-4-quentin@isovalent.com
2021-10-25 17:31:38 -07:00
Quentin Monnet 46241271d1 bpftool: Do not expose and init hash maps for pinned path in main.c
BPF programs, maps, and links, can all be listed with their pinned paths
by bpftool, when the "-f" option is provided. To do so, bpftool builds
hash maps containing all pinned paths for each kind of objects.

These three hash maps are always initialised in main.c, and exposed
through main.h. There appear to be no particular reason to do so: we can
just as well make them static to the files that need them (prog.c,
map.c, and link.c respectively), and initialise them only when we want
to show objects and the "-f" switch is provided.

This may prevent unnecessary memory allocations if the implementation of
the hash maps was to change in the future.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211023205154.6710-3-quentin@isovalent.com
2021-10-25 17:31:38 -07:00
Quentin Monnet c07ba629df tools: bpftool: Update and synchronise option list in doc and help msg
All bpftool commands support the options for JSON output and debug from
libbpf. In addition, some commands support additional options
corresponding to specific use cases.

The list of options described in the man pages for the different
commands are not always accurate. The messages for interactive help are
mostly limited to HELP_SPEC_OPTIONS, and are even less representative of
the actual set of options supported for the commands.

Let's update the lists:

- HELP_SPEC_OPTIONS is modified to contain the "default" options (JSON
  and debug), and to be extensible (no ending curly bracket).
- All commands use HELP_SPEC_OPTIONS in their help message, and then
  complete the list with their specific options.
- The lists of options in the man pages are updated.
- The formatting of the list for bpftool.rst is adjusted to match
  formatting for the other man pages. This is for consistency, and also
  because it will be helpful in a future patch to automatically check
  that the files are synchronised.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210730215435.7095-5-quentin@isovalent.com
2021-07-30 15:40:27 -07:00
Alexei Starovoitov d510296d33 bpftool: Use syscall/loader program in "prog load" and "gen skeleton" command.
Add -L flag to bpftool to use libbpf gen_trace facility and syscall/loader program
for skeleton generation and program loading.

"bpftool gen skeleton -L" command will generate a "light skeleton" or "loader skeleton"
that is similar to existing skeleton, but has one major difference:
$ bpftool gen skeleton lsm.o > lsm.skel.h
$ bpftool gen skeleton -L lsm.o > lsm.lskel.h
$ diff lsm.skel.h lsm.lskel.h
@@ -5,34 +4,34 @@
 #define __LSM_SKEL_H__

 #include <stdlib.h>
-#include <bpf/libbpf.h>
+#include <bpf/bpf.h>

The light skeleton does not use majority of libbpf infrastructure.
It doesn't need libelf. It doesn't parse .o file.
It only needs few sys_bpf wrappers. All of them are in bpf/bpf.h file.
In future libbpf/bpf.c can be inlined into bpf.h, so not even libbpf.a would be
needed to work with light skeleton.

"bpftool prog load -L file.o" command is introduced for debugging of syscall/loader
program generation. Just like the same command without -L it will try to load
the programs from file.o into the kernel. It won't even try to pin them.

"bpftool prog load -L -d file.o" command will provide additional debug messages
on how syscall/loader program was generated.
Also the execution of syscall/loader program will use bpf_trace_printk() for
each step of loading BTF, creating maps, and loading programs.
The user can do "cat /.../trace_pipe" for further debug.

An example of fexit_sleep.lskel.h generated from progs/fexit_sleep.c:
struct fexit_sleep {
	struct bpf_loader_ctx ctx;
	struct {
		struct bpf_map_desc bss;
	} maps;
	struct {
		struct bpf_prog_desc nanosleep_fentry;
		struct bpf_prog_desc nanosleep_fexit;
	} progs;
	struct {
		int nanosleep_fentry_fd;
		int nanosleep_fexit_fd;
	} links;
	struct fexit_sleep__bss {
		int pid;
		int fentry_cnt;
		int fexit_cnt;
	} *bss;
};

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210514003623.28033-18-alexei.starovoitov@gmail.com
2021-05-19 00:41:31 +02:00
Andrii Nakryiko 75fa177769 tools/bpftool: Add bpftool support for split BTF
Add ability to work with split BTF by providing extra -B flag, which allows to
specify the path to the base BTF file.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-12-andrii@kernel.org
2020-11-05 18:37:31 -08:00
Andrii Nakryiko 09f44b753a tools/bpftool: Fix compilation warnings in 32-bit mode
Fix few compilation warnings in bpftool when compiling in 32-bit mode.
Abstract away u64 to pointer conversion into a helper function.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-2-andriin@fb.com
2020-08-13 16:45:41 -07:00
Tony Ambardar 9165e1d70f bpftool: Use only nftw for file tree parsing
The bpftool sources include code to walk file trees, but use multiple
frameworks to do so: nftw and fts. While nftw conforms to POSIX/SUSv3 and
is widely available, fts is not conformant and less common, especially on
non-glibc systems. The inconsistent framework usage hampers maintenance
and portability of bpftool, in particular for embedded systems.

Standardize code usage by rewriting one fts-based function to use nftw and
clean up some related function warnings by extending use of "const char *"
arguments. This change helps in building bpftool against musl for OpenWrt.

Also fix an unsafe call to dirname() by duplicating the string to pass,
since some implementations may directly alter it. The same approach is
used in libbpf.c.

Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200721024817.13701-1-Tony.Ambardar@gmail.com
2020-07-21 23:42:56 +02:00
Tobias Klauser 16d37ee3d2 tools, bpftool: Define attach_type_name array only once
Define attach_type_name in common.c instead of main.h so it is only
defined once. This leads to a slight decrease in the binary size of
bpftool.

Before:

   text	   data	    bss	    dec	    hex	filename
 399024	  11168	1573160	1983352	 1e4378	bpftool

After:

   text	   data	    bss	    dec	    hex	filename
 398256	  10880	1573160	1982296	 1e3f58	bpftool

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200624143154.13145-1-tklauser@distanz.ch
2020-06-25 16:06:01 +02:00
Tobias Klauser 9023497d87 tools, bpftool: Define prog_type_name array only once
Define prog_type_name in prog.c instead of main.h so it is only defined
once. This leads to a slight decrease in the binary size of bpftool.

Before:

   text	   data	    bss	    dec	    hex	filename
 401032	  11936	1573160	1986128	 1e4e50	bpftool

After:

   text	   data	    bss	    dec	    hex	filename
 399024	  11168	1573160	1983352	 1e4378	bpftool

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200624143124.12914-1-tklauser@distanz.ch
2020-06-25 16:06:01 +02:00
Andrii Nakryiko d53dee3fe0 tools/bpftool: Show info for processes holding BPF map/prog/link/btf FDs
Add bpf_iter-based way to find all the processes that hold open FDs against
BPF object (map, prog, link, btf). bpftool always attempts to discover this,
but will silently give up if kernel doesn't yet support bpf_iter BPF programs.
Process name and PID are emitted for each process (task group).

Sample output for each of 4 BPF objects:

$ sudo ./bpftool prog show
2694: cgroup_device  tag 8c42dee26e8cd4c2  gpl
        loaded_at 2020-06-16T15:34:32-0700  uid 0
        xlated 648B  jited 409B  memlock 4096B
        pids systemd(1)
2907: cgroup_skb  name egress  tag 9ad187367cf2b9e8  gpl
        loaded_at 2020-06-16T18:06:54-0700  uid 0
        xlated 48B  jited 59B  memlock 4096B  map_ids 2436
        btf_id 1202
        pids test_progs(2238417), test_progs(2238445)

$ sudo ./bpftool map show
2436: array  name test_cgr.bss  flags 0x400
        key 4B  value 8B  max_entries 1  memlock 8192B
        btf_id 1202
        pids test_progs(2238417), test_progs(2238445)
2445: array  name pid_iter.rodata  flags 0x480
        key 4B  value 4B  max_entries 1  memlock 8192B
        btf_id 1214  frozen
        pids bpftool(2239612)

$ sudo ./bpftool link show
61: cgroup  prog 2908
        cgroup_id 375301  attach_type egress
        pids test_progs(2238417), test_progs(2238445)
62: cgroup  prog 2908
        cgroup_id 375344  attach_type egress
        pids test_progs(2238417), test_progs(2238445)

$ sudo ./bpftool btf show
1202: size 1527B  prog_ids 2908,2907  map_ids 2436
        pids test_progs(2238417), test_progs(2238445)
1242: size 34684B
        pids bpftool(2258892)

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-9-andriin@fb.com
2020-06-22 17:01:49 -07:00
Andrii Nakryiko 16e9b187ab tools/bpftool: Minimize bootstrap bpftool
Build minimal "bootstrap mode" bpftool to enable skeleton (and, later,
vmlinux.h generation), instead of building almost complete, but slightly
different (w/o skeletons, etc) bpftool to bootstrap complete bpftool build.

Current approach doesn't scale well (engineering-wise) when adding more BPF
programs to bpftool and other complicated functionality, as it requires
constant adjusting of the code to work in both bootstrapped mode and normal
mode.

So it's better to build only minimal bpftool version that supports only BPF
skeleton code generation and BTF-to-C conversion. Thankfully, this is quite
easy to accomplish due to internal modularity of bpftool commands. This will
also allow to keep adding new functionality to bpftool in general, without the
need to care about bootstrap mode for those new parts of bpftool.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-6-andriin@fb.com
2020-06-22 17:01:48 -07:00
Andrii Nakryiko a479b8ce4e tools/bpftool: Move map/prog parsing logic into common
Move functions that parse map and prog by id/tag/name/etc outside of
map.c/prog.c, respectively. These functions are used outside of those files
and are generic enough to be in common. This also makes heavy-weight map.c and
prog.c more decoupled from the rest of bpftool files and facilitates more
lightweight bootstrap bpftool variant.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-5-andriin@fb.com
2020-06-22 17:01:48 -07:00
Daniel Borkmann 05ee19c18c bpf, bpftool: Enable get{peer, sock}name attach types
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
2020-05-19 11:32:04 -07:00
Quentin Monnet 6e7e034e88 tools, bpftool: Poison and replace kernel integer typedefs
Replace the use of kernel-only integer typedefs (u8, u32, etc.) by their
user space counterpart (__u8, __u32, etc.).

Similarly to what libbpf does, poison the typedefs to avoid introducing
them again in the future.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200511161536.29853-2-quentin@isovalent.com
2020-05-11 21:20:46 +02:00
Yonghong Song 9406b485de tools/bpftool: Add bpf_iter support for bptool
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
2020-05-09 17:05:27 -07:00
Andrii Nakryiko c5481f9a95 bpftool: Add bpf_link show and pin support
Add `bpftool link show` and `bpftool link pin` commands.

Example plain output for `link show` (with showing pinned paths):

[vmuser@archvm bpf]$ sudo ~/local/linux/tools/bpf/bpftool/bpftool -f link
1: tracing  prog 12
        prog_type tracing  attach_type fentry
        pinned /sys/fs/bpf/my_test_link
        pinned /sys/fs/bpf/my_test_link2
2: tracing  prog 13
        prog_type tracing  attach_type fentry
3: tracing  prog 14
        prog_type tracing  attach_type fentry
4: tracing  prog 15
        prog_type tracing  attach_type fentry
5: tracing  prog 16
        prog_type tracing  attach_type fentry
6: tracing  prog 17
        prog_type tracing  attach_type fentry
7: raw_tracepoint  prog 21
        tp 'sys_enter'
8: cgroup  prog 25
        cgroup_id 584  attach_type egress
9: cgroup  prog 25
        cgroup_id 599  attach_type egress
10: cgroup  prog 25
        cgroup_id 614  attach_type egress
11: cgroup  prog 25
        cgroup_id 629  attach_type egress

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200429001614.1544-9-andriin@fb.com
2020-04-28 17:27:08 -07:00
Andrii Nakryiko 50325b1761 bpftool: Expose attach_type-to-string array to non-cgroup code
Move attach_type_strings into main.h for access in non-cgroup code.
bpf_attach_type is used for non-cgroup attach types quite widely now. So also
complete missing string translations for non-cgroup attach types.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200429001614.1544-8-andriin@fb.com
2020-04-28 17:27:08 -07:00
Martin KaFai Lau 65c9362859 bpftool: Add struct_ops support
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
2020-03-20 15:51:35 +01:00
Martin KaFai Lau d5ae04da34 bpftool: Translate prog_id to its bpf prog_name
The kernel struct_ops obj has kernel's func ptrs implemented by bpf_progs.
The bpf prog_id is stored as the value of the func ptr for introspection
purpose.  In the latter patch, a struct_ops dump subcmd will be added
to introspect these func ptrs.  It is desired to print the actual bpf
prog_name instead of only printing the prog_id.

Since struct_ops is the only usecase storing prog_id in the func ptr,
this patch adds a prog_id_as_func_ptr bool (default is false) to
"struct btf_dumper" in order not to mis-interpret the ptr value
for the other existing use-cases.

While printing a func_ptr as a bpf prog_name,
this patch also prefix the bpf prog_name with the ptr's func_proto.
[ Note that it is the ptr's func_proto instead of the bpf prog's
  func_proto ]
It reuses the current btf_dump_func() to obtain the ptr's func_proto
string.

Here is an example from the bpf_cubic.c:
"void (struct sock *, u32, u32) bictcp_cong_avoid/prog_id:140"

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/20200318171650.129252-1-kafai@fb.com
2020-03-20 15:51:35 +01:00
Quentin Monnet 6ae32b29c0 tools: bpftool: Restore message on failure to guess program type
In commit 4a3d6c6a6e ("libbpf: Reduce log level for custom section
names"), log level for messages for libbpf_attach_type_by_name() and
libbpf_prog_type_by_name() was downgraded from "info" to "debug". The
latter function, in particular, is used by bpftool when attempting to
load programs, and this change caused bpftool to exit with no hint or
error message when it fails to detect the type of the program to load
(unless "-d" option was provided).

To help users understand why bpftool fails to load the program, let's do
a second run of the function with log level in "debug" mode in case of
failure.

Before:

    # bpftool prog load sample_ret0.o /sys/fs/bpf/sample_ret0
    # echo $?
    255

Or really verbose with -d flag:

    # bpftool -d prog load sample_ret0.o /sys/fs/bpf/sample_ret0
    libbpf: loading sample_ret0.o
    libbpf: section(1) .strtab, size 134, link 0, flags 0, type=3
    libbpf: skip section(1) .strtab
    libbpf: section(2) .text, size 16, link 0, flags 6, type=1
    libbpf: found program .text
    libbpf: section(3) .debug_abbrev, size 55, link 0, flags 0, type=1
    libbpf: skip section(3) .debug_abbrev
    libbpf: section(4) .debug_info, size 75, link 0, flags 0, type=1
    libbpf: skip section(4) .debug_info
    libbpf: section(5) .rel.debug_info, size 32, link 14, flags 0, type=9
    libbpf: skip relo .rel.debug_info(5) for section(4)
    libbpf: section(6) .debug_str, size 150, link 0, flags 30, type=1
    libbpf: skip section(6) .debug_str
    libbpf: section(7) .BTF, size 155, link 0, flags 0, type=1
    libbpf: section(8) .BTF.ext, size 80, link 0, flags 0, type=1
    libbpf: section(9) .rel.BTF.ext, size 32, link 14, flags 0, type=9
    libbpf: skip relo .rel.BTF.ext(9) for section(8)
    libbpf: section(10) .debug_frame, size 40, link 0, flags 0, type=1
    libbpf: skip section(10) .debug_frame
    libbpf: section(11) .rel.debug_frame, size 16, link 14, flags 0, type=9
    libbpf: skip relo .rel.debug_frame(11) for section(10)
    libbpf: section(12) .debug_line, size 74, link 0, flags 0, type=1
    libbpf: skip section(12) .debug_line
    libbpf: section(13) .rel.debug_line, size 16, link 14, flags 0, type=9
    libbpf: skip relo .rel.debug_line(13) for section(12)
    libbpf: section(14) .symtab, size 96, link 1, flags 0, type=2
    libbpf: looking for externs among 4 symbols...
    libbpf: collected 0 externs total
    libbpf: failed to guess program type from ELF section '.text'
    libbpf: supported section(type) names are: socket sk_reuseport kprobe/ [...]

After:

    # bpftool prog load sample_ret0.o /sys/fs/bpf/sample_ret0
    libbpf: failed to guess program type from ELF section '.text'
    libbpf: supported section(type) names are: socket sk_reuseport kprobe/ [...]

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200311021205.9755-1-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-03-13 12:49:51 -07:00
Quentin Monnet 75a1e792c3 tools: bpftool: Allow all prog/map handles for pinning objects
Documentation and interactive help for bpftool have always explained
that the regular handles for programs (id|name|tag|pinned) and maps
(id|name|pinned) can be passed to the utility when attempting to pin
objects (bpftool prog pin PROG / bpftool map pin MAP).

THIS IS A LIE!! The tool actually accepts only ids, as the parsing is
done in do_pin_any() in common.c instead of reusing the parsing
functions that have long been generic for program and map handles.

Instead of fixing the doc, fix the code. It is trivial to reuse the
generic parsing, and to simplify do_pin_any() in the process.

Do not accept to pin multiple objects at the same time with
prog_parse_fds() or map_parse_fds() (this would require a more complex
syntax for passing multiple sysfs paths and validating that they
correspond to the number of e.g. programs we find for a given name or
tag).

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200312184608.12050-2-quentin@isovalent.com
2020-03-13 00:24:08 +01:00
Andrey Ignatov 3494bec0f6 bpftool: Support struct_ops, tracing, ext prog types
Add support for prog types that were added to kernel but not present in
bpftool yet: struct_ops, tracing, ext prog types and corresponding
section names.

Before:
  # bpftool p l
  ...
  184: type 26  name test_subprog3  tag dda135a7dc0daf54  gpl
          loaded_at 2020-02-25T13:28:33-0800  uid 0
          xlated 112B  jited 103B  memlock 4096B  map_ids 136
          btf_id 85
  185: type 28  name new_get_skb_len  tag d2de5b87d8e5dc49  gpl
          loaded_at 2020-02-25T13:28:33-0800  uid 0
          xlated 72B  jited 69B  memlock 4096B  map_ids 136
          btf_id 85

After:
  # bpftool p l
  ...
  184: tracing  name test_subprog3  tag dda135a7dc0daf54  gpl
          loaded_at 2020-02-25T13:28:33-0800  uid 0
          xlated 112B  jited 103B  memlock 4096B  map_ids 136
          btf_id 85
  185: ext  name new_get_skb_len  tag d2de5b87d8e5dc49  gpl
          loaded_at 2020-02-25T13:28:33-0800  uid 0
          xlated 72B  jited 69B  memlock 4096B  map_ids 136
          btf_id 85

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200225223441.689109-1-rdna@fb.com
2020-02-26 16:40:53 +01:00
Andrii Nakryiko 985ead416d bpftool: Add skeleton codegen command
Add `bpftool gen skeleton` command, which takes in compiled BPF .o object file
and dumps a BPF skeleton struct and related code to work with that skeleton.
Skeleton itself is tailored to a specific structure of provided BPF object
file, containing accessors (just plain struct fields) for every map and
program, as well as dedicated space for bpf_links. If BPF program is using
global variables, corresponding structure definitions of compatible memory
layout are emitted as well, making it possible to initialize and subsequently
read/update global variables values using simple and clear C syntax for
accessing fields. This skeleton majorly improves usability of
opening/loading/attaching of BPF object, as well as interacting with it
throughout the lifetime of loaded BPF object.

Generated skeleton struct has the following structure:

struct <object-name> {
	/* used by libbpf's skeleton API */
	struct bpf_object_skeleton *skeleton;
	/* bpf_object for libbpf APIs */
	struct bpf_object *obj;
	struct {
		/* for every defined map in BPF object: */
		struct bpf_map *<map-name>;
	} maps;
	struct {
		/* for every program in BPF object: */
		struct bpf_program *<program-name>;
	} progs;
	struct {
		/* for every program in BPF object: */
		struct bpf_link *<program-name>;
	} links;
	/* for every present global data section: */
	struct <object-name>__<one of bss, data, or rodata> {
		/* memory layout of corresponding data section,
		 * with every defined variable represented as a struct field
		 * with exactly the same type, but without const/volatile
		 * modifiers, e.g.:
		 */
		 int *my_var_1;
		 ...
	} *<one of bss, data, or rodata>;
};

This provides great usability improvements:
- no need to look up maps and programs by name, instead just
  my_obj->maps.my_map or my_obj->progs.my_prog would give necessary
  bpf_map/bpf_program pointers, which user can pass to existing libbpf APIs;
- pre-defined places for bpf_links, which will be automatically populated for
  program types that libbpf knows how to attach automatically (currently
  tracepoints, kprobe/kretprobe, raw tracepoint and tracing programs). On
  tearing down skeleton, all active bpf_links will be destroyed (meaning BPF
  programs will be detached, if they are attached). For cases in which libbpf
  doesn't know how to auto-attach BPF program, user can manually create link
  after loading skeleton and they will be auto-detached on skeleton
  destruction:

	my_obj->links.my_fancy_prog = bpf_program__attach_cgroup_whatever(
		my_obj->progs.my_fancy_prog, <whatever extra param);

- it's extremely easy and convenient to work with global data from userspace
  now. Both for read-only and read/write variables, it's possible to
  pre-initialize them before skeleton is loaded:

	skel = my_obj__open(raw_embed_data);
	my_obj->rodata->my_var = 123;
	my_obj__load(skel); /* 123 will be initialization value for my_var */

  After load, if kernel supports mmap() for BPF arrays, user can still read
  (and write for .bss and .data) variables values, but at that point it will
  be directly mmap()-ed to BPF array, backing global variables. This allows to
  seamlessly exchange data with BPF side. From userspace program's POV, all
  the pointers and memory contents stay the same, but mapped kernel memory
  changes to point to created map.
  If kernel doesn't yet support mmap() for BPF arrays, it's still possible to
  use those data section structs to pre-initialize .bss, .data, and .rodata,
  but after load their pointers will be reset to NULL, allowing user code to
  gracefully handle this condition, if necessary.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191214014341.3442258-14-andriin@fb.com
2019-12-15 15:58:05 -08:00
Paul Chaignon 99f9863a0c bpftool: Match maps by name
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
2019-12-15 09:03:18 -08:00
Paul Chaignon a7d22ca2a4 bpftool: Match programs by name
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
2019-12-15 09:03:18 -08:00
Andrii Nakryiko 32e3e58e4c bpftool: Fix bpftool build by switching to bpf_object__open_file()
As part of libbpf in 5e61f27070 ("libbpf: stop enforcing kern_version,
populate it for users") non-LIBBPF_API __bpf_object__open_xattr() API
was removed from libbpf.h header. This broke bpftool, which relied on
that function. This patch fixes the build by switching to newly added
bpf_object__open_file() which provides the same capabilities, but is
official and future-proof API.

v1->v2:
- fix prog_type shadowing (Stanislav).

Fixes: 5e61f27070 ("libbpf: stop enforcing kern_version, populate it for users")
Reported-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20191007225604.2006146-1-andriin@fb.com
2019-10-07 18:44:28 -07:00
Quentin Monnet 8918dc42dc tools: bpftool: move "__printf()" attributes to header file
Some functions in bpftool have a "__printf()" format attributes to tell
the compiler they should expect printf()-like arguments. But because
these attributes are not used for the function prototypes in the header
files, the compiler does not run the checks everywhere the functions are
used, and some mistakes on format string and corresponding arguments
slipped in over time.

Let's move the __printf() attributes to the correct places.

Note: We add guards around the definition of GCC_VERSION in
tools/include/linux/compiler-gcc.h to prevent a conflict in jit_disasm.c
on GCC_VERSION from headers pulled via libbfd.

Fixes: c101189bc9 ("tools: bpftool: fix -Wmissing declaration warnings")
Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com>
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>
2019-08-15 22:06:46 -07:00
Daniel T. Lee 216b65fb70 tools: bpftool: add raw_tracepoint_writable prog type to header
From commit 9df1c28bb7 ("bpf: add writable context for raw tracepoints"),
a new type of BPF_PROG, RAW_TRACEPOINT_WRITABLE has been added.

Since this BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE is not listed at
bpftool's header, it causes a segfault when executing 'bpftool feature'.

This commit adds BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE entry to
prog_type_name enum, and will eventually fixes the segfault issue.

Fixes: 9df1c28bb7 ("bpf: add writable context for raw tracepoints")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-12 15:14:42 +02:00
Quentin Monnet ba95c74524 tools: bpftool: add "prog run" subcommand to test-run programs
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>
2019-07-05 23:48:07 +02:00
Stanislav Fomichev f6d08d9d85 bpftool: support cgroup sockopt
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>
2019-06-27 15:25:17 -07:00
Quentin Monnet 55d778076b tools: bpftool: make -d option print debug output from verifier
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>
2019-05-28 11:03:26 +02:00
Andrii Nakryiko c93cc69004 bpftool: add ability to dump BTF types
Add new `btf dump` sub-command to bpftool. It allows to dump
human-readable low-level BTF types representation of BTF types. BTF can
be retrieved from few different sources:
  - from BTF object by ID;
  - from PROG, if it has associated BTF;
  - from MAP, if it has associated BTF data; it's possible to narrow
    down types to either key type, value type, both, or all BTF types;
  - from ELF file (.BTF section).

Output format mostly follows BPF verifier log format with few notable
exceptions:
  - all the type/field/param/etc names are enclosed in single quotes to
    allow easier grepping and to stand out a little bit more;
  - FUNC_PROTO output follows STRUCT/UNION/ENUM format of having one
    line per each argument; this is more uniform and allows easy
    grepping, as opposed to succinct, but inconvenient format that BPF
    verifier log is using.

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>
2019-04-25 21:45:14 -07:00