Commit Graph

25634 Commits

Author SHA1 Message Date
Andrii Nakryiko
7d8a819dd3 libbpf: Install skel_internal.h header used from light skeletons
Light skeleton code assumes skel_internal.h header to be installed system-wide
by libbpf package. Make sure it is actually installed.

Fixes: 6723474373 ("libbpf: Generate loader program out of BPF ELF file.")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210603004026.2698513-4-andrii@kernel.org
2021-06-03 15:50:11 +02:00
Andrii Nakryiko
232c9e8bd5 libbpf: Refactor header installation portions of Makefile
As we gradually get more headers that have to be installed, it's quite
annoying to copy/paste long $(call) commands. So extract that logic and do
a simple $(foreach) over the list of headers.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210603004026.2698513-3-andrii@kernel.org
2021-06-03 15:50:11 +02:00
Andrii Nakryiko
16cac00606 libbpf: Move few APIs from 0.4 to 0.5 version
Official libbpf 0.4 release doesn't include three APIs that were tentatively
put into 0.4 section. Fix libbpf.map and move these three APIs:

  - bpf_map__initial_value;
  - bpf_map_lookup_and_delete_elem_flags;
  - bpf_object__gen_loader.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210603004026.2698513-2-andrii@kernel.org
2021-06-03 15:50:05 +02:00
Yonghong Song
fc8c262e0e bpf, docs: Add llvm_reloc.rst to explain llvm bpf relocations
LLVM upstream commit https://reviews.llvm.org/D102712 made some changes
to bpf relocations to make them llvm linker lld friendly. The scope of
existing relocations R_BPF_64_{64,32} is narrowed and new relocations
R_BPF_64_{ABS32,ABS64,NODYLD32} are introduced.

Let us add some documentation about llvm bpf relocations so people can
understand how to resolve them properly in their respective tools.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210526152457.335210-1-yhs@fb.com
2021-05-28 22:12:04 +02:00
Florent Revest
d6a6a55518 libbpf: Move BPF_SEQ_PRINTF and BPF_SNPRINTF to bpf_helpers.h
These macros are convenient wrappers around the bpf_seq_printf and
bpf_snprintf helpers. They are currently provided by bpf_tracing.h which
targets low level tracing primitives. bpf_helpers.h is a better fit.

The __bpf_narg and __bpf_apply are needed in both files and provided
twice. __bpf_empty isn't used anywhere and is removed from bpf_tracing.h

Reported-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210526164643.2881368-1-revest@chromium.org
2021-05-26 10:45:41 -07:00
Hangbin Liu
d232924762 selftests/bpf: Add xdp_redirect_multi test
Add a bpf selftest for new helper xdp_redirect_map_multi(). In this
test there are 3 forward groups and 1 exclude group. The test will
redirect each interface's packets to all the interfaces in the forward
group, and exclude the interface in exclude map.

Two maps (DEVMAP, DEVMAP_HASH) and two xdp modes (generic, drive) will
be tested. XDP egress program will also be tested by setting pkt src MAC
to egress interface's MAC address.

For more test details, you can find it in the test script. Here is
the test result.
]# time ./test_xdp_redirect_multi.sh
Pass: xdpgeneric arp(F_BROADCAST) ns1-1
Pass: xdpgeneric arp(F_BROADCAST) ns1-2
Pass: xdpgeneric arp(F_BROADCAST) ns1-3
Pass: xdpgeneric IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-1
Pass: xdpgeneric IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-2
Pass: xdpgeneric IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-3
Pass: xdpgeneric IPv6 (no flags) ns1-1
Pass: xdpgeneric IPv6 (no flags) ns1-2
Pass: xdpdrv arp(F_BROADCAST) ns1-1
Pass: xdpdrv arp(F_BROADCAST) ns1-2
Pass: xdpdrv arp(F_BROADCAST) ns1-3
Pass: xdpdrv IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-1
Pass: xdpdrv IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-2
Pass: xdpdrv IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-3
Pass: xdpdrv IPv6 (no flags) ns1-1
Pass: xdpdrv IPv6 (no flags) ns1-2
Pass: xdpegress mac ns1-2
Pass: xdpegress mac ns1-3
Summary: PASS 18, FAIL 0

real    1m18.321s
user    0m0.123s
sys     0m0.350s

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210519090747.1655268-5-liuhangbin@gmail.com
2021-05-26 09:46:16 +02:00
Hangbin Liu
e624d4ed4a xdp: Extend xdp_redirect_map with broadcast support
This patch adds two flags BPF_F_BROADCAST and BPF_F_EXCLUDE_INGRESS to
extend xdp_redirect_map for broadcast support.

With BPF_F_BROADCAST the packet will be broadcasted to all the interfaces
in the map. with BPF_F_EXCLUDE_INGRESS the ingress interface will be
excluded when do broadcasting.

When getting the devices in dev hash map via dev_map_hash_get_next_key(),
there is a possibility that we fall back to the first key when a device
was removed. This will duplicate packets on some interfaces. So just walk
the whole buckets to avoid this issue. For dev array map, we also walk the
whole map to find valid interfaces.

Function bpf_clear_redirect_map() was removed in
commit ee75aef23a ("bpf, xdp: Restructure redirect actions").
Add it back as we need to use ri->map again.

With test topology:
  +-------------------+             +-------------------+
  | Host A (i40e 10G) |  ---------- | eno1(i40e 10G)    |
  +-------------------+             |                   |
                                    |   Host B          |
  +-------------------+             |                   |
  | Host C (i40e 10G) |  ---------- | eno2(i40e 10G)    |
  +-------------------+             |                   |
                                    |          +------+ |
                                    | veth0 -- | Peer | |
                                    | veth1 -- |      | |
                                    | veth2 -- |  NS  | |
                                    |          +------+ |
                                    +-------------------+

On Host A:
 # pktgen/pktgen_sample03_burst_single_flow.sh -i eno1 -d $dst_ip -m $dst_mac -s 64

On Host B(Intel(R) Xeon(R) CPU E5-2690 v3 @ 2.60GHz, 128G Memory):
Use xdp_redirect_map and xdp_redirect_map_multi in samples/bpf for testing.
All the veth peers in the NS have a XDP_DROP program loaded. The
forward_map max_entries in xdp_redirect_map_multi is modify to 4.

Testing the performance impact on the regular xdp_redirect path with and
without patch (to check impact of additional check for broadcast mode):

5.12 rc4         | redirect_map        i40e->i40e      |    2.0M |  9.7M
5.12 rc4         | redirect_map        i40e->veth      |    1.7M | 11.8M
5.12 rc4 + patch | redirect_map        i40e->i40e      |    2.0M |  9.6M
5.12 rc4 + patch | redirect_map        i40e->veth      |    1.7M | 11.7M

Testing the performance when cloning packets with the redirect_map_multi
test, using a redirect map size of 4, filled with 1-3 devices:

5.12 rc4 + patch | redirect_map multi  i40e->veth (x1) |    1.7M | 11.4M
5.12 rc4 + patch | redirect_map multi  i40e->veth (x2) |    1.1M |  4.3M
5.12 rc4 + patch | redirect_map multi  i40e->veth (x3) |    0.8M |  2.6M

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20210519090747.1655268-3-liuhangbin@gmail.com
2021-05-26 09:46:16 +02:00
Andrii Nakryiko
9c6c0449de bpftool: Set errno on skeleton failures and propagate errors
Follow libbpf's error handling conventions and pass through errors and errno
properly. Skeleton code always returned NULL on errors (not ERR_PTR(err)), so
there are no backwards compatibility concerns. But now we also set errno
properly, so it's possible to distinguish different reasons for failure, if
necessary.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210525035935.1461796-6-andrii@kernel.org
2021-05-25 17:32:35 -07:00
Andrii Nakryiko
e9fc3ce99b libbpf: Streamline error reporting for high-level APIs
Implement changes to error reporting for high-level libbpf APIs to make them
less surprising and less error-prone to users:
  - in all the cases when error happens, errno is set to an appropriate error
    value;
  - in libbpf 1.0 mode, all pointer-returning APIs return NULL on error and
    error code is communicated through errno; this applies both to APIs that
    already returned NULL before (so now they communicate more detailed error
    codes), as well as for many APIs that used ERR_PTR() macro and encoded
    error numbers as fake pointers.
  - in legacy (default) mode, those APIs that were returning ERR_PTR(err),
    continue doing so, but still set errno.

With these changes, errno can be always used to extract actual error,
regardless of legacy or libbpf 1.0 modes. This is utilized internally in
libbpf in places where libbpf uses it's own high-level APIs.
libbpf_get_error() is adapted to handle both cases completely transparently to
end-users (and is used by libbpf consistently as well).

More context, justification, and discussion can be found in "Libbpf: the road
to v1.0" document ([0]).

  [0] https://docs.google.com/document/d/1UyjTZuPFWiPFyKk1tV5an11_iaRuec6U-ZESZ54nNTY

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210525035935.1461796-5-andrii@kernel.org
2021-05-25 17:32:35 -07:00
Andrii Nakryiko
f12b654327 libbpf: Streamline error reporting for low-level APIs
Ensure that low-level APIs behave uniformly across the libbpf as follows:
  - in case of an error, errno is always set to the correct error code;
  - when libbpf 1.0 mode is enabled with LIBBPF_STRICT_DIRECT_ERRS option to
    libbpf_set_strict_mode(), return -Exxx error value directly, instead of -1;
  - by default, until libbpf 1.0 is released, keep returning -1 directly.

More context, justification, and discussion can be found in "Libbpf: the road
to v1.0" document ([0]).

  [0] https://docs.google.com/document/d/1UyjTZuPFWiPFyKk1tV5an11_iaRuec6U-ZESZ54nNTY

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210525035935.1461796-4-andrii@kernel.org
2021-05-25 17:32:35 -07:00
Andrii Nakryiko
bad2e478af selftests/bpf: Turn on libbpf 1.0 mode and fix all IS_ERR checks
Turn ony libbpf 1.0 mode. Fix all the explicit IS_ERR checks that now will be
broken because libbpf returns NULL on error (and sets errno). Fix
ASSERT_OK_PTR and ASSERT_ERR_PTR to work for both old mode and new modes and
use them throughout selftests. This is trivial to do by using
libbpf_get_error() API that all libbpf users are supposed to use, instead of
IS_ERR checks.

A bunch of checks also did explicit -1 comparison for various fd-returning
APIs. Such checks are replaced with >= 0 or < 0 cases.

There were also few misuses of bpf_object__find_map_by_name() in test_maps.
Those are fixed in this patch as well.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210525035935.1461796-3-andrii@kernel.org
2021-05-25 17:32:35 -07:00
Andrii Nakryiko
5981881d21 libbpf: Add libbpf_set_strict_mode() API to turn on libbpf 1.0 behaviors
Add libbpf_set_strict_mode() API that allows application to simulate libbpf
1.0 breaking changes before libbpf 1.0 is released. This will help users
migrate gradually and with confidence.

For now only ALL or NONE options are available, subsequent patches will add
more flags. This patch is preliminary for selftests/bpf changes.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210525035935.1461796-2-andrii@kernel.org
2021-05-25 17:32:34 -07:00
Yonghong Song
9f0c317f6a libbpf: Add support for new llvm bpf relocations
LLVM patch https://reviews.llvm.org/D102712
narrowed the scope of existing R_BPF_64_64
and R_BPF_64_32 relocations, and added three
new relocations, R_BPF_64_ABS64, R_BPF_64_ABS32
and R_BPF_64_NODYLD32. The main motivation is
to make relocations linker friendly.

This change, unfortunately, breaks libbpf build,
and we will see errors like below:
  libbpf: ELF relo #0 in section #6 has unexpected type 2 in
     /home/yhs/work/bpf-next/tools/testing/selftests/bpf/bpf_tcp_nogpl.o
  Error: failed to link
     '/home/yhs/work/bpf-next/tools/testing/selftests/bpf/bpf_tcp_nogpl.o':
     Unknown error -22 (-22)
The new relocation R_BPF_64_ABS64 is generated
and libbpf linker sanity check doesn't understand it.
Relocation section '.rel.struct_ops' at offset 0x1410 contains 1 entries:
    Offset             Info             Type               Symbol's Value  Symbol's Name
0000000000000018  0000000700000002 R_BPF_64_ABS64         0000000000000000 nogpltcp_init

Look at the selftests/bpf/bpf_tcp_nogpl.c,
  void BPF_STRUCT_OPS(nogpltcp_init, struct sock *sk)
  {
  }

  SEC(".struct_ops")
  struct tcp_congestion_ops bpf_nogpltcp = {
          .init           = (void *)nogpltcp_init,
          .name           = "bpf_nogpltcp",
  };
The new llvm relocation scheme categorizes 'nogpltcp_init' reference
as R_BPF_64_ABS64 instead of R_BPF_64_64 which is used to specify
ld_imm64 relocation in the new scheme.

Let us fix the linker sanity checking by including
R_BPF_64_ABS64 and R_BPF_64_ABS32. There is no need to
check R_BPF_64_NODYLD32 which is used for .BTF and .BTF.ext.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210522162341.3687617-1-yhs@fb.com
2021-05-24 21:03:05 -07:00
Denis Salopek
49c299b694 selftests/bpf: Add bpf_lookup_and_delete_elem tests
Add bpf selftests and extend existing ones for a new function
bpf_lookup_and_delete_elem() for (percpu) hash and (percpu) LRU hash map
types.
In test_lru_map and test_maps we add an element, lookup_and_delete it,
then check whether it's deleted.
The newly added lookup_and_delete prog tests practically do the same
thing but additionally use a BPF program to change the value of the
element for LRU maps.

Signed-off-by: Denis Salopek <denis.salopek@sartura.hr>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/d30d3e0060c1f750e133579623cf1c60ff58f3d9.1620763117.git.denis.salopek@sartura.hr
2021-05-24 13:30:52 -07:00
Denis Salopek
d59b9f2d1b bpf: Extend libbpf with bpf_map_lookup_and_delete_elem_flags
Add bpf_map_lookup_and_delete_elem_flags() libbpf API in order to use
the BPF_F_LOCK flag with the map_lookup_and_delete_elem() function.

Signed-off-by: Denis Salopek <denis.salopek@sartura.hr>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/15b05dafe46c7e0750d110f233977372029d1f62.1620763117.git.denis.salopek@sartura.hr
2021-05-24 13:30:51 -07:00
Denis Salopek
3e87f192b4 bpf: Add lookup_and_delete_elem support to hashtab
Extend the existing bpf_map_lookup_and_delete_elem() functionality to
hashtab map types, in addition to stacks and queues.
Create a new hashtab bpf_map_ops function that does lookup and deletion
of the element under the same bucket lock and add the created map_ops to
bpf.h.

Signed-off-by: Denis Salopek <denis.salopek@sartura.hr>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/4d18480a3e990ffbf14751ddef0325eed3be2966.1620763117.git.denis.salopek@sartura.hr
2021-05-24 13:30:26 -07:00
Stanislav Fomichev
f9bceaa59c libbpf: Skip bpf_object__probe_loading for light skeleton
I'm getting the following error when running 'gen skeleton -L' as
regular user:

libbpf: Error in bpf_object__probe_loading():Operation not permitted(1).
Couldn't load trivial BPF program. Make sure your kernel supports BPF
(CONFIG_BPF_SYSCALL=y) and/or that RLIMIT_MEMLOCK is set to big enough
value.

Fixes: 6723474373 ("libbpf: Generate loader program out of BPF ELF file.")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210521030653.2626513-1-sdf@google.com
2021-05-24 12:22:09 -07:00
Po-Hsu Lin
25173dd409 selftests: net: devlink_port_split.py: skip the test if no devlink device
When there is no devlink device, the following command will return:
  $ devlink -j dev show
  {dev:{}}

This will cause IndexError when trying to access the first element
in dev of this json dataset. Use the kselftest framework skip code
to skip this test in this case.

Example output with this change:
  # selftests: net: devlink_port_split.py
  # no devlink device was found, test skipped
  ok 7 selftests: net: devlink_port_split.py # SKIP

Link: https://bugs.launchpad.net/bugs/1928889
Signed-off-by: Po-Hsu Lin <po-hsu.lin@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-20 15:46:57 -07:00
David S. Miller
7b16509b29 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-05-19

The following pull-request contains BPF updates for your *net-next* tree.

We've added 43 non-merge commits during the last 11 day(s) which contain
a total of 74 files changed, 3717 insertions(+), 578 deletions(-).

The main changes are:

1) syscall program type, fd array, and light skeleton, from Alexei.

2) Stop emitting static variables in skeleton, from Andrii.

3) Low level tc-bpf api, from Kumar.

4) Reduce verifier kmalloc/kfree churn, from Lorenz.
====================
2021-05-19 12:58:29 -07:00
Alexei Starovoitov
5d67f34959 bpf: Add cmd alias BPF_PROG_RUN
Add BPF_PROG_RUN command as an alias to BPF_RPOG_TEST_RUN to better
indicate the full range of use cases done by the command.

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210519014032.20908-1-alexei.starovoitov@gmail.com
2021-05-19 15:35:12 +02:00
Alexei Starovoitov
1a532eb28d selftests/bpf: Convert test trace_printk to lskel.
Convert test trace_printk to light skeleton to check
rodata support in lskel.

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/20210514003623.28033-22-alexei.starovoitov@gmail.com
2021-05-19 00:42:20 +02:00
Alexei Starovoitov
eb0f1e0c7f selftests/bpf: Convert test printk to use rodata.
Convert test trace_printk to more aggressively validate and use rodata.

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/20210514003623.28033-21-alexei.starovoitov@gmail.com
2021-05-19 00:42:08 +02:00
Alexei Starovoitov
0a93066299 selftests/bpf: Convert atomics test to light skeleton.
Convert prog_tests/atomics.c to lskel.h

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/20210514003623.28033-20-alexei.starovoitov@gmail.com
2021-05-19 00:41:56 +02:00
Alexei Starovoitov
4d1b629861 selftests/bpf: Convert few tests to light skeleton.
Convert few tests that don't use CO-RE to light skeleton.

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/20210514003623.28033-19-alexei.starovoitov@gmail.com
2021-05-19 00:41:44 +02:00
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
Alexei Starovoitov
7723256bf2 libbpf: Introduce bpf_map__initial_value().
Introduce bpf_map__initial_value() to read initial contents
of mmaped data/rodata/bss maps.
Note that bpf_map__set_initial_value() doesn't allow modifying
kconfig map while bpf_map__initial_value() allows reading
its values.

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/20210514003623.28033-17-alexei.starovoitov@gmail.com
2021-05-19 00:40:56 +02:00
Alexei Starovoitov
30f51aedab libbpf: Cleanup temp FDs when intermediate sys_bpf fails.
Fix loader program to close temporary FDs when intermediate
sys_bpf command fails.

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/20210514003623.28033-16-alexei.starovoitov@gmail.com
2021-05-19 00:40:44 +02:00
Alexei Starovoitov
6723474373 libbpf: Generate loader program out of BPF ELF file.
The BPF program loading process performed by libbpf is quite complex
and consists of the following steps:
"open" phase:
- parse elf file and remember relocations, sections
- collect externs and ksyms including their btf_ids in prog's BTF
- patch BTF datasec (since llvm couldn't do it)
- init maps (old style map_def, BTF based, global data map, kconfig map)
- collect relocations against progs and maps
"load" phase:
- probe kernel features
- load vmlinux BTF
- resolve externs (kconfig and ksym)
- load program BTF
- init struct_ops
- create maps
- apply CO-RE relocations
- patch ld_imm64 insns with src_reg=PSEUDO_MAP, PSEUDO_MAP_VALUE, PSEUDO_BTF_ID
- reposition subprograms and adjust call insns
- sanitize and load progs

During this process libbpf does sys_bpf() calls to load BTF, create maps,
populate maps and finally load programs.
Instead of actually doing the syscalls generate a trace of what libbpf
would have done and represent it as the "loader program".
The "loader program" consists of single map with:
- union bpf_attr(s)
- BTF bytes
- map value bytes
- insns bytes
and single bpf program that passes bpf_attr(s) and data into bpf_sys_bpf() helper.
Executing such "loader program" via bpf_prog_test_run() command will
replay the sequence of syscalls that libbpf would have done which will result
the same maps created and programs loaded as specified in the elf file.
The "loader program" removes libelf and majority of libbpf dependency from
program loading process.

kconfig, typeless ksym, struct_ops and CO-RE are not supported yet.

The order of relocate_data and relocate_calls had to change, so that
bpf_gen__prog_load() can see all relocations for a given program with
correct insn_idx-es.

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/20210514003623.28033-15-alexei.starovoitov@gmail.com
2021-05-19 00:39:40 +02:00
Alexei Starovoitov
e2fa0156a4 libbpf: Preliminary support for fd_idx
Prep libbpf to use FD_IDX kernel feature when generating loader program.

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/20210514003623.28033-14-alexei.starovoitov@gmail.com
2021-05-19 00:33:41 +02:00
Alexei Starovoitov
9ca1f56aba libbpf: Add bpf_object pointer to kernel_supports().
Add a pointer to 'struct bpf_object' to kernel_supports() helper.
It will be used in the next patch.
No functional changes.

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/20210514003623.28033-13-alexei.starovoitov@gmail.com
2021-05-19 00:33:40 +02:00
Alexei Starovoitov
b126882672 libbpf: Change the order of data and text relocations.
In order to be able to generate loader program in the later
patches change the order of data and text relocations.
Also improve the test to include data relos.

If the kernel supports "FD array" the map_fd relocations can be processed
before text relos since generated loader program won't need to manually
patch ld_imm64 insns with map_fd.
But ksym and kfunc relocations can only be processed after all calls
are relocated, since loader program will consist of a sequence
of calls to bpf_btf_find_by_name_kind() followed by patching of btf_id
and btf_obj_fd into corresponding ld_imm64 insns. The locations of those
ld_imm64 insns are specified in relocations.
Hence process all data relocations (maps, ksym, kfunc) together after call relos.

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/20210514003623.28033-12-alexei.starovoitov@gmail.com
2021-05-19 00:33:40 +02:00
Alexei Starovoitov
3abea08924 bpf: Add bpf_sys_close() helper.
Add bpf_sys_close() helper to be used by the syscall/loader program to close
intermediate FDs and other cleanup.
Note this helper must never be allowed inside fdget/fdput bracketing.

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/20210514003623.28033-11-alexei.starovoitov@gmail.com
2021-05-19 00:33:40 +02:00
Alexei Starovoitov
3d78417b60 bpf: Add bpf_btf_find_by_name_kind() helper.
Add new helper:
long bpf_btf_find_by_name_kind(char *name, int name_sz, u32 kind, int flags)
Description
	Find BTF type with given name and kind in vmlinux BTF or in module's BTFs.
Return
	Returns btf_id and btf_obj_fd in lower and upper 32 bits.

It will be used by loader program to find btf_id to attach the program to
and to find btf_ids of ksyms.

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/20210514003623.28033-10-alexei.starovoitov@gmail.com
2021-05-19 00:33:40 +02:00
Alexei Starovoitov
387544bfa2 bpf: Introduce fd_idx
Typical program loading sequence involves creating bpf maps and applying
map FDs into bpf instructions in various places in the bpf program.
This job is done by libbpf that is using compiler generated ELF relocations
to patch certain instruction after maps are created and BTFs are loaded.
The goal of fd_idx is to allow bpf instructions to stay immutable
after compilation. At load time the libbpf would still create maps as usual,
but it wouldn't need to patch instructions. It would store map_fds into
__u32 fd_array[] and would pass that pointer to sys_bpf(BPF_PROG_LOAD).

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/20210514003623.28033-9-alexei.starovoitov@gmail.com
2021-05-19 00:33:40 +02:00
Alexei Starovoitov
2341d6bb13 selftests/bpf: Test for btf_load command.
Improve selftest to check that btf_load is working from bpf program.

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/20210514003623.28033-8-alexei.starovoitov@gmail.com
2021-05-19 00:33:40 +02:00
Alexei Starovoitov
00899e7e8d selftests/bpf: Test for syscall program type
bpf_prog_type_syscall is a program that creates a bpf map,
updates it, and loads another bpf program using bpf_sys_bpf() helper.

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/20210514003623.28033-6-alexei.starovoitov@gmail.com
2021-05-19 00:33:40 +02:00
Alexei Starovoitov
5452fc9a17 libbpf: Support for syscall program type
Trivial support for syscall program type.

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/20210514003623.28033-5-alexei.starovoitov@gmail.com
2021-05-19 00:33:40 +02:00
Alexei Starovoitov
79a7f8bdb1 bpf: Introduce bpf_sys_bpf() helper and program type.
Add placeholders for bpf_sys_bpf() helper and new program type.
Make sure to check that expected_attach_type is zero for future extensibility.
Allow tracing helper functions to be used in this program type, since they will
only execute from user context via bpf_prog_test_run.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210514003623.28033-2-alexei.starovoitov@gmail.com
2021-05-19 00:33:39 +02:00
Ido Schimmel
b7715acba4 selftests: forwarding: Add test for custom multipath hash with IPv6 GRE
Test that when the hash policy is set to custom, traffic is distributed
only according to the inner fields set in the fib_multipath_hash_fields
sysctl.

Each time set a different field and make sure traffic is only
distributed when the field is changed in the packet stream.

The test only verifies the behavior of IPv4/IPv6 overlays on top of an
IPv6 underlay network. The previous patch verified the same with an IPv4
underlay network.

Example output:

 # ./ip6gre_custom_multipath_hash.sh
 TEST: ping                                                          [ OK ]
 TEST: ping6                                                         [ OK ]
 INFO: Running IPv4 overlay custom multipath hash tests
 TEST: Multipath hash field: Inner source IP (balanced)              [ OK ]
 INFO: Packets sent on path1 / path2: 6602 / 6002
 TEST: Multipath hash field: Inner source IP (unbalanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 1 / 12601
 TEST: Multipath hash field: Inner destination IP (balanced)         [ OK ]
 INFO: Packets sent on path1 / path2: 6802 / 5801
 TEST: Multipath hash field: Inner destination IP (unbalanced)       [ OK ]
 INFO: Packets sent on path1 / path2: 12602 / 3
 TEST: Multipath hash field: Inner source port (balanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 16431 / 16344
 TEST: Multipath hash field: Inner source port (unbalanced)          [ OK ]
 INFO: Packets sent on path1 / path2: 0 / 32773
 TEST: Multipath hash field: Inner destination port (balanced)       [ OK ]
 INFO: Packets sent on path1 / path2: 16431 / 16344
 TEST: Multipath hash field: Inner destination port (unbalanced)     [ OK ]
 INFO: Packets sent on path1 / path2: 2 / 32772
 INFO: Running IPv6 overlay custom multipath hash tests
 TEST: Multipath hash field: Inner source IP (balanced)              [ OK ]
 INFO: Packets sent on path1 / path2: 6704 / 5902
 TEST: Multipath hash field: Inner source IP (unbalanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 1 / 12600
 TEST: Multipath hash field: Inner destination IP (balanced)         [ OK ]
 INFO: Packets sent on path1 / path2: 5751 / 6852
 TEST: Multipath hash field: Inner destination IP (unbalanced)       [ OK ]
 INFO: Packets sent on path1 / path2: 12602 / 0
 TEST: Multipath hash field: Inner flowlabel (balanced)              [ OK ]
 INFO: Packets sent on path1 / path2: 8272 / 8181
 TEST: Multipath hash field: Inner flowlabel (unbalanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 3 / 12602
 TEST: Multipath hash field: Inner source port (balanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 16424 / 16351
 TEST: Multipath hash field: Inner source port (unbalanced)          [ OK ]
 INFO: Packets sent on path1 / path2: 3 / 32774
 TEST: Multipath hash field: Inner destination port (balanced)       [ OK ]
 INFO: Packets sent on path1 / path2: 16425 / 16350
 TEST: Multipath hash field: Inner destination port (unbalanced)     [ OK ]
 INFO: Packets sent on path1 / path2: 2 / 32773

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18 13:27:32 -07:00
Ido Schimmel
185b0c190b selftests: forwarding: Add test for custom multipath hash with IPv4 GRE
Test that when the hash policy is set to custom, traffic is distributed
only according to the inner fields set in the fib_multipath_hash_fields
sysctl.

Each time set a different field and make sure traffic is only
distributed when the field is changed in the packet stream.

The test only verifies the behavior of IPv4/IPv6 overlays on top of an
IPv4 underlay network. A subsequent patch will do the same with an IPv6
underlay network.

Example output:

 # ./gre_custom_multipath_hash.sh
 TEST: ping                                                          [ OK ]
 TEST: ping6                                                         [ OK ]
 INFO: Running IPv4 overlay custom multipath hash tests
 TEST: Multipath hash field: Inner source IP (balanced)              [ OK ]
 INFO: Packets sent on path1 / path2: 6601 / 6001
 TEST: Multipath hash field: Inner source IP (unbalanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 0 / 12600
 TEST: Multipath hash field: Inner destination IP (balanced)         [ OK ]
 INFO: Packets sent on path1 / path2: 6802 / 5802
 TEST: Multipath hash field: Inner destination IP (unbalanced)       [ OK ]
 INFO: Packets sent on path1 / path2: 12601 / 1
 TEST: Multipath hash field: Inner source port (balanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 16430 / 16344
 TEST: Multipath hash field: Inner source port (unbalanced)          [ OK ]
 INFO: Packets sent on path1 / path2: 0 / 32772
 TEST: Multipath hash field: Inner destination port (balanced)       [ OK ]
 INFO: Packets sent on path1 / path2: 16430 / 16343
 TEST: Multipath hash field: Inner destination port (unbalanced)     [ OK ]
 INFO: Packets sent on path1 / path2: 0 / 32772
 INFO: Running IPv6 overlay custom multipath hash tests
 TEST: Multipath hash field: Inner source IP (balanced)              [ OK ]
 INFO: Packets sent on path1 / path2: 6702 / 5900
 TEST: Multipath hash field: Inner source IP (unbalanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 0 / 12601
 TEST: Multipath hash field: Inner destination IP (balanced)         [ OK ]
 INFO: Packets sent on path1 / path2: 5751 / 6851
 TEST: Multipath hash field: Inner destination IP (unbalanced)       [ OK ]
 INFO: Packets sent on path1 / path2: 12602 / 1
 TEST: Multipath hash field: Inner flowlabel (balanced)              [ OK ]
 INFO: Packets sent on path1 / path2: 8364 / 8065
 TEST: Multipath hash field: Inner flowlabel (unbalanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 12601 / 0
 TEST: Multipath hash field: Inner source port (balanced)            [ OK ]
 INFO: Packets sent on path1 / path2: 16425 / 16349
 TEST: Multipath hash field: Inner source port (unbalanced)          [ OK ]
 INFO: Packets sent on path1 / path2: 1 / 32770
 TEST: Multipath hash field: Inner destination port (balanced)       [ OK ]
 INFO: Packets sent on path1 / path2: 16425 / 16349
 TEST: Multipath hash field: Inner destination port (unbalanced)     [ OK ]
 INFO: Packets sent on path1 / path2: 2 / 32770

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18 13:27:32 -07:00
Ido Schimmel
511e8db540 selftests: forwarding: Add test for custom multipath hash
Test that when the hash policy is set to custom, traffic is distributed
only according to the outer fields set in the fib_multipath_hash_fields
sysctl.

Each time set a different field and make sure traffic is only
distributed when the field is changed in the packet stream.

The test only verifies the behavior with non-encapsulated IPv4 and IPv6
packets. Subsequent patches will add tests for IPv4/IPv6 overlays on top
of IPv4/IPv6 underlay networks.

Example output:

 # ./custom_multipath_hash.sh
 TEST: ping                                                          [ OK ]
 TEST: ping6                                                         [ OK ]
 INFO: Running IPv4 custom multipath hash tests
 TEST: Multipath hash field: Source IP (balanced)                    [ OK ]
 INFO: Packets sent on path1 / path2: 6353 / 6254
 TEST: Multipath hash field: Source IP (unbalanced)                  [ OK ]
 INFO: Packets sent on path1 / path2: 0 / 12600
 TEST: Multipath hash field: Destination IP (balanced)               [ OK ]
 INFO: Packets sent on path1 / path2: 6102 / 6502
 TEST: Multipath hash field: Destination IP (unbalanced)             [ OK ]
 INFO: Packets sent on path1 / path2: 1 / 12601
 TEST: Multipath hash field: Source port (balanced)                  [ OK ]
 INFO: Packets sent on path1 / path2: 16428 / 16345
 TEST: Multipath hash field: Source port (unbalanced)                [ OK ]
 INFO: Packets sent on path1 / path2: 32770 / 2
 TEST: Multipath hash field: Destination port (balanced)             [ OK ]
 INFO: Packets sent on path1 / path2: 16428 / 16345
 TEST: Multipath hash field: Destination port (unbalanced)           [ OK ]
 INFO: Packets sent on path1 / path2: 32770 / 2
 INFO: Running IPv6 custom multipath hash tests
 TEST: Multipath hash field: Source IP (balanced)                    [ OK ]
 INFO: Packets sent on path1 / path2: 6704 / 5903
 TEST: Multipath hash field: Source IP (unbalanced)                  [ OK ]
 INFO: Packets sent on path1 / path2: 12600 / 0
 TEST: Multipath hash field: Destination IP (balanced)               [ OK ]
 INFO: Packets sent on path1 / path2: 5551 / 7052
 TEST: Multipath hash field: Destination IP (unbalanced)             [ OK ]
 INFO: Packets sent on path1 / path2: 12603 / 0
 TEST: Multipath hash field: Flowlabel (balanced)                    [ OK ]
 INFO: Packets sent on path1 / path2: 8378 / 8080
 TEST: Multipath hash field: Flowlabel (unbalanced)                  [ OK ]
 INFO: Packets sent on path1 / path2: 2 / 12603
 TEST: Multipath hash field: Source port (balanced)                  [ OK ]
 INFO: Packets sent on path1 / path2: 16385 / 16388
 TEST: Multipath hash field: Source port (unbalanced)                [ OK ]
 INFO: Packets sent on path1 / path2: 0 / 32774
 TEST: Multipath hash field: Destination port (balanced)             [ OK ]
 INFO: Packets sent on path1 / path2: 16386 / 16390
 TEST: Multipath hash field: Destination port (unbalanced)           [ OK ]
 INFO: Packets sent on path1 / path2: 32771 / 2

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18 13:27:32 -07:00
Petr Machata
b4d786941b selftests: mlxsw: qos_lib: Drop __mlnx_qos
Now that the two users of this helper have been converted to iproute2 dcb,
it is not necessary anymore. Drop it.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-17 15:15:46 -07:00
Petr Machata
b0bab2298e selftests: mlxsw: qos_pfc: Convert to iproute2 dcb
There is a dedicated tool for configuration of DCB in iproute2 now. Use it
in the selftest instead of mlnx_qos.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-17 15:15:46 -07:00
Petr Machata
9a1cac062d selftests: mlxsw: qos_headroom: Convert to iproute2 dcb
There is a dedicated tool for configuration of DCB in iproute2 now. Use it
in the selftest instead of mlnx_qos.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-17 15:15:46 -07:00
Ido Schimmel
16355c0b10 selftests: mlxsw: Make sampling test more robust
The test sometimes fails with an error message such as:

TEST: tc sample (w/ flower) rate (egress)                           [FAIL]
	Expected 100 packets, got 70 packets, which is -30% off. Required accuracy is +-25%

Make the test more robust by generating more packets, therefore
increasing the number of expected samples. Decrease the transmission
delay in order not to needlessly prolong the test.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-17 15:15:46 -07:00
Danielle Ratson
5d01071e64 selftests: mlxsw: Make the unsplit array global in port_scale test
Currently, the array of the ports that were split in the port_scale test
is local, so the port_cleanup() unsplits an empty array.

Make the array global so the cleanup will be preformed properly.

Suggested-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-17 15:15:46 -07:00
Seth David Schoen
6101ca0384 selftests: Lowest IPv4 address in a subnet is valid
Expect the lowest IPv4 address in a subnet to be assignable
and addressable as a unicast (non-broadcast) address on a
local network segment.

Signed-off-by: Seth David Schoen <schoen@loyalty.org>
Suggested-by: John Gilmore <gnu@toad.com>
Acked-by: Dave Taht <dave.taht@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-17 13:47:58 -07:00
Kumar Kartikeya Dwivedi
f18ba26da8 libbpf: Add selftests for TC-BPF management API
This adds some basic tests for the low level bpf_tc_* API.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210512103451.989420-4-memxor@gmail.com
2021-05-17 17:52:20 +02:00
Kumar Kartikeya Dwivedi
715c5ce454 libbpf: Add low level TC-BPF management API
This adds functions that wrap the netlink API used for adding, manipulating,
and removing traffic control filters.

The API summary:

A bpf_tc_hook represents a location where a TC-BPF filter can be attached.
This means that creating a hook leads to creation of the backing qdisc,
while destruction either removes all filters attached to a hook, or destroys
qdisc if requested explicitly (as discussed below).

The TC-BPF API functions operate on this bpf_tc_hook to attach, replace,
query, and detach tc filters. All functions return 0 on success, and a
negative error code on failure.

bpf_tc_hook_create - Create a hook
Parameters:
	@hook - Cannot be NULL, ifindex > 0, attach_point must be set to
		proper enum constant. Note that parent must be unset when
		attach_point is one of BPF_TC_INGRESS or BPF_TC_EGRESS. Note
		that as an exception BPF_TC_INGRESS|BPF_TC_EGRESS is also a
		valid value for attach_point.

		Returns -EOPNOTSUPP when hook has attach_point as BPF_TC_CUSTOM.

bpf_tc_hook_destroy - Destroy a hook
Parameters:
	@hook - Cannot be NULL. The behaviour depends on value of
		attach_point. If BPF_TC_INGRESS, all filters attached to
		the ingress hook will be detached. If BPF_TC_EGRESS, all
		filters attached to the egress hook will be detached. If
		BPF_TC_INGRESS|BPF_TC_EGRESS, the clsact qdisc will be
		deleted, also detaching all filters. As before, parent must
		be unset for these attach_points, and set for BPF_TC_CUSTOM.

		It is advised that if the qdisc is operated on by many programs,
		then the program at least check that there are no other existing
		filters before deleting the clsact qdisc. An example is shown
		below:

		DECLARE_LIBBPF_OPTS(bpf_tc_hook, .ifindex = if_nametoindex("lo"),
				    .attach_point = BPF_TC_INGRESS);
		/* set opts as NULL, as we're not really interested in
		 * getting any info for a particular filter, but just
	 	 * detecting its presence.
		 */
		r = bpf_tc_query(&hook, NULL);
		if (r == -ENOENT) {
			/* no filters */
			hook.attach_point = BPF_TC_INGRESS|BPF_TC_EGREESS;
			return bpf_tc_hook_destroy(&hook);
		} else {
			/* failed or r == 0, the latter means filters do exist */
			return r;
		}

		Note that there is a small race between checking for no
		filters and deleting the qdisc. This is currently unavoidable.

		Returns -EOPNOTSUPP when hook has attach_point as BPF_TC_CUSTOM.

bpf_tc_attach - Attach a filter to a hook
Parameters:
	@hook - Cannot be NULL. Represents the hook the filter will be
		attached to. Requirements for ifindex and attach_point are
		same as described in bpf_tc_hook_create, but BPF_TC_CUSTOM
		is also supported.  In that case, parent must be set to the
		handle where the filter will be attached (using BPF_TC_PARENT).
		E.g. to set parent to 1:16 like in tc command line, the
		equivalent would be BPF_TC_PARENT(1, 16).

	@opts - Cannot be NULL. The following opts are optional:
		* handle   - The handle of the filter
		* priority - The priority of the filter
			     Must be >= 0 and <= UINT16_MAX
		Note that when left unset, they will be auto-allocated by
		the kernel. The following opts must be set:
		* prog_fd - The fd of the loaded SCHED_CLS prog
		The following opts must be unset:
		* prog_id - The ID of the BPF prog
		The following opts are optional:
		* flags - Currently only BPF_TC_F_REPLACE is allowed. It
			  allows replacing an existing filter instead of
			  failing with -EEXIST.
		The following opts will be filled by bpf_tc_attach on a
		successful attach operation if they are unset:
		* handle   - The handle of the attached filter
		* priority - The priority of the attached filter
		* prog_id  - The ID of the attached SCHED_CLS prog
		This way, the user can know what the auto allocated values
		for optional opts like handle and priority are for the newly
		attached filter, if they were unset.

		Note that some other attributes are set to fixed default
		values listed below (this holds for all bpf_tc_* APIs):
		protocol as ETH_P_ALL, direct action mode, chain index of 0,
		and class ID of 0 (this can be set by writing to the
		skb->tc_classid field from the BPF program).

bpf_tc_detach
Parameters:
	@hook - Cannot be NULL. Represents the hook the filter will be
		detached from. Requirements are same as described above
		in bpf_tc_attach.

	@opts - Cannot be NULL. The following opts must be set:
		* handle, priority
		The following opts must be unset:
		* prog_fd, prog_id, flags

bpf_tc_query
Parameters:
	@hook - Cannot be NULL. Represents the hook where the filter lookup will
		be performed. Requirements are same as described above in
		bpf_tc_attach().

	@opts - Cannot be NULL. The following opts must be set:
		* handle, priority
		The following opts must be unset:
		* prog_fd, prog_id, flags
		The following fields will be filled by bpf_tc_query upon a
		successful lookup:
		* prog_id

Some usage examples (using BPF skeleton infrastructure):

BPF program (test_tc_bpf.c):

	#include <linux/bpf.h>
	#include <bpf/bpf_helpers.h>

	SEC("classifier")
	int cls(struct __sk_buff *skb)
	{
		return 0;
	}

Userspace loader:

	struct test_tc_bpf *skel = NULL;
	int fd, r;

	skel = test_tc_bpf__open_and_load();
	if (!skel)
		return -ENOMEM;

	fd = bpf_program__fd(skel->progs.cls);

	DECLARE_LIBBPF_OPTS(bpf_tc_hook, hook, .ifindex =
			    if_nametoindex("lo"), .attach_point =
			    BPF_TC_INGRESS);
	/* Create clsact qdisc */
	r = bpf_tc_hook_create(&hook);
	if (r < 0)
		goto end;

	DECLARE_LIBBPF_OPTS(bpf_tc_opts, opts, .prog_fd = fd);
	r = bpf_tc_attach(&hook, &opts);
	if (r < 0)
		goto end;
	/* Print the auto allocated handle and priority */
	printf("Handle=%u", opts.handle);
	printf("Priority=%u", opts.priority);

	opts.prog_fd = opts.prog_id = 0;
	bpf_tc_detach(&hook, &opts);
end:
	test_tc_bpf__destroy(skel);

This is equivalent to doing the following using tc command line:
  # tc qdisc add dev lo clsact
  # tc filter add dev lo ingress bpf obj foo.o sec classifier da
  # tc filter del dev lo ingress handle <h> prio <p> bpf
... where the handle and priority can be found using:
  # tc filter show dev lo ingress

Another example replacing a filter (extending prior example):

	/* We can also choose both (or one), let's try replacing an
	 * existing filter.
	 */
	DECLARE_LIBBPF_OPTS(bpf_tc_opts, replace_opts, .handle =
			    opts.handle, .priority = opts.priority,
			    .prog_fd = fd);
	r = bpf_tc_attach(&hook, &replace_opts);
	if (r == -EEXIST) {
		/* Expected, now use BPF_TC_F_REPLACE to replace it */
		replace_opts.flags = BPF_TC_F_REPLACE;
		return bpf_tc_attach(&hook, &replace_opts);
	} else if (r < 0) {
		return r;
	}
	/* There must be no existing filter with these
	 * attributes, so cleanup and return an error.
	 */
	replace_opts.prog_fd = replace_opts.prog_id = 0;
	bpf_tc_detach(&hook, &replace_opts);
	return -1;

To obtain info of a particular filter:

	/* Find info for filter with handle 1 and priority 50 */
	DECLARE_LIBBPF_OPTS(bpf_tc_opts, info_opts, .handle = 1,
			    .priority = 50);
	r = bpf_tc_query(&hook, &info_opts);
	if (r == -ENOENT)
		printf("Filter not found");
	else if (r < 0)
		return r;
	printf("Prog ID: %u", info_opts.prog_id);
	return 0;

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net> # libbpf API design
[ Daniel: also did major patch cleanup ]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210512103451.989420-3-memxor@gmail.com
2021-05-17 17:48:45 +02:00
Kumar Kartikeya Dwivedi
8bbb77b7c7 libbpf: Add various netlink helpers
This change introduces a few helpers to wrap open coded attribute
preparation in netlink.c. It also adds a libbpf_netlink_send_recv() that
is useful to wrap send + recv handling in a generic way. Subsequent patch
will also use this function for sending and receiving a netlink response.
The libbpf_nl_get_link() helper has been removed instead, moving socket
creation into the newly named libbpf_netlink_send_recv().

Every nested attribute's closure must happen using the helper
nlattr_end_nested(), which sets its length properly. NLA_F_NESTED is
enforced using nlattr_begin_nested() helper. Other simple attributes
can be added directly.

The maxsz parameter corresponds to the size of the request structure
which is being filled in, so for instance with req being:

  struct {
	struct nlmsghdr nh;
	struct tcmsg t;
	char buf[4096];
  } req;

Then, maxsz should be sizeof(req).

This change also converts the open coded attribute preparation with these
helpers. Note that the only failure the internal call to nlattr_add()
could result in the nested helper would be -EMSGSIZE, hence that is what
we return to our caller.

The libbpf_netlink_send_recv() call takes care of opening the socket,
sending the netlink message, receiving the response, potentially invoking
callbacks, and return errors if any, and then finally close the socket.
This allows users to avoid identical socket setup code in different places.
The only user of libbpf_nl_get_link() has been converted to make use of it.
__bpf_set_link_xdp_fd_replace() has also been refactored to use it.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
[ Daniel: major patch cleanup ]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210512103451.989420-2-memxor@gmail.com
2021-05-17 17:48:36 +02:00