selftests/bpf: fix lots of silly mistakes pointed out by compiler

Once we enable -Wall for BPF sources, compiler will complain about lots
of unused variables, variables that are set but never read, etc.

Fix all these issues first before enabling -Wall in Makefile.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230309054015.4068562-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Fix build errors if CONFIG_NF_CONNTRACK=m

If CONFIG_NF_CONNTRACK=m, there are no definitions of NF_NAT_MANIP_SRC
and NF_NAT_MANIP_DST in vmlinux.h, build test_bpf_nf.c failed.

$ make -C tools/testing/selftests/bpf/

CLNG-BPF [test_maps] test_bpf_nf.bpf.o
progs/test_bpf_nf.c:160:42: error: use of undeclared identifier 'NF_NAT_MANIP_SRC'
bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
^
progs/test_bpf_nf.c:163:42: error: use of undeclared identifier 'NF_NAT_MANIP_DST'
bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
^
2 errors generated.

Copy the definitions in include/net/netfilter/nf_nat.h to test_bpf_nf.c,
in order to avoid redefinitions if CONFIG_NF_CONNTRACK=y, rename them with
___local suffix. This is similar with commit 1058b6a78db2 ("selftests/bpf:
Do not fail build if CONFIG_NF_CONNTRACK=m/n").

Fixes: b06b45e82b59 ("selftests/bpf: add tests for bpf_ct_set_nat_info kfunc")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/1674028604-7113-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

selftests/bpf: add tests for bpf_ct_set_nat_info kfunc

Introduce self-tests for bpf_ct_set_nat_info kfunc used to set the
source or destination nat addresses/ports.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/803e33294e247744d466943105879414344d3235.1663778601.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: fix ct status check in bpf_nf selftests

Check properly the connection tracking entry status configured running
bpf_ct_change_status kfunc.
Remove unnecessary IPS_CONFIRMED status configuration since it is
already done during entry allocation.

Fixes: 6eb7fba007a7 ("selftests/bpf: Add tests for new nf_conntrack kfuncs")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/813a5161a71911378dfac8770ec890428e4998aa.1662623574.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Add tests for writing to nf_conn:mark

Add a simple extension to the existing selftest to write to
nf_conn:mark. Also add a failure test for writing to unsupported field.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Link: https://lore.kernel.org/r/f78966b81b9349d2b8ebb4cee2caf15cb6b38ee2.1662568410.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Add connmark read test

Test that the prog can read from the connection mark. This test is nice
because it ensures progs can interact with netfilter subsystem
correctly.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/bpf/d3bc620a491e4c626c20d80631063922cbe13e2b.1660254747.git.dxu@dxuuu.xyz

selftests/bpf: Add existing connection bpf_*_ct_lookup() test

Add a test where we do a conntrack lookup on an existing connection.
This is nice because it's a more realistic test than artifically
creating a ct entry and looking it up afterwards.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/bpf/de5a617832f38f8b5631cc87e2a836da7c94d497.1660254747.git.dxu@dxuuu.xyz

selftests/bpf: Add tests for new nf_conntrack kfuncs

Introduce selftests for the following kfunc helpers:
- bpf_xdp_ct_alloc
- bpf_skb_ct_alloc
- bpf_ct_insert_entry
- bpf_ct_set_timeout
- bpf_ct_change_timeout
- bpf_ct_set_status
- bpf_ct_change_status

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220721134245.2450-12-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Do not fail build if CONFIG_NF_CONNTRACK=m/n

Some users have complained that selftests fail to build when
CONFIG_NF_CONNTRACK=m. It would be useful to allow building as long as
it is set to module or built-in, even though in case of building as
module, user would need to load it before running the selftest. Note
that this also allows building selftest when CONFIG_NF_CONNTRACK is
disabled.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220120164932.2798544-1-memxor@gmail.com

selftests/bpf: Add test for unstable CT lookup API

This tests that we return errors as documented, and also that the kfunc
calls work from both XDP and TC hooks.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-8-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>