selftests/bpf: detect testing prog flags support

Various tests specify extra testing prog_flags when loading BPF
programs, like BPF_F_TEST_RND_HI32, and more recently also
BPF_F_TEST_REG_INVARIANTS. While BPF_F_TEST_RND_HI32 is old enough to
not cause much problem on older kernels, BPF_F_TEST_REG_INVARIANTS is
very fresh and unconditionally specifying it causes selftests to fail on
even slightly outdated kernels.

This breaks libbpf CI test against 4.9 and 5.15 kernels, it can break
some local development (done outside of VM), etc.

To prevent this, and guard against similar problems in the future, do
runtime detection of supported "testing flags", and only provide those
that host kernel recognizes.

Acked-by: Song Liu <song@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240109231738.575844-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

bpf: rename BPF_F_TEST_SANITY_STRICT to BPF_F_TEST_REG_INVARIANTS

Rename verifier internal flag BPF_F_TEST_SANITY_STRICT to more neutral
BPF_F_TEST_REG_INVARIANTS. This is a follow up to [0].

A few selftests and veristat need to be adjusted in the same patch as
well.

[0] https://patchwork.kernel.org/project/netdevbpf/patch/20231112010609.848406-5-andrii@kernel.org/

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231117171404.225508-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: set BPF_F_TEST_SANITY_SCRIPT by default

Make sure to set BPF_F_TEST_SANITY_STRICT program flag by default across
most verifier tests (and a bunch of others that set custom prog flags).

There are currently two tests that do fail validation, if enforced
strictly: verifier_bounds/crossing_64_bit_signed_boundary_2 and
verifier_bounds/crossing_32_bit_signed_boundary_2. To accommodate them,
we teach test_loader a flag negation:

__flag(!<flagname>) will *clear* specified flag, allowing easy opt-out.

We apply __flag(!BPF_F_TEST_SANITY_STRICT) to these to tests.

Also sprinkle BPF_F_TEST_SANITY_STRICT everywhere where we already set
test-only BPF_F_TEST_RND_HI32 flag, for completeness.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231112010609.848406-12-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Store BPF object files with .bpf.o extension

BPF object files are, in a way, the final artifact produced as part of
the ahead-of-time compilation process. That makes them somewhat special
compared to "regular" object files, which are a intermediate build
artifacts that can typically be removed safely. As such, it can make
sense to name them differently to make it easier to spot this difference
at a glance.

Among others, libbpf-bootstrap [0] has established the extension .bpf.o
for BPF object files. It seems reasonable to follow this example and
establish the same denomination for selftest build artifacts. To that
end, this change adjusts the corresponding part of the build system and
the test programs loading BPF object files to work with .bpf.o files.

[0] https://github.com/libbpf/libbpf-bootstrap

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220901222253.1199242-1-deso@posteo.net

selftests/bpf: 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. After
this change, the header tools/testing/selftests/bpf/bpf_rlimit.h can be
removed.

This patch also removes the useless header sys/resource.h from many files
in tools/testing/selftests/bpf/.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220409125958.92629-3-laoar.shao@gmail.com

selftests/bpf: Clean up array_size.cocci warnings

Clean up the array_size.cocci warnings under tools/testing/selftests/bpf/:

Use `ARRAY_SIZE(arr)` instead of forms like `sizeof(arr)/sizeof(arr[0])`.

tools/testing/selftests/bpf/test_cgroup_storage.c uses ARRAY_SIZE() defined
in tools/include/linux/kernel.h (sys/sysinfo.h -> linux/kernel.h), while
others use ARRAY_SIZE() in bpf_util.h.

Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220315130143.2403-1-guozhengkui@vivo.com

selftests/bpf: Remove all the uses of deprecated bpf_prog_load_xattr()

Migrate all the selftests that were still using bpf_prog_load_xattr().
Few are converted to skeleton, others will use bpf_object__open_file()
API.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211201232824.3166325-7-andrii@kernel.org

selftests/bpf: Convert legacy prog load APIs to bpf_prog_load()

Convert all the uses of legacy low-level BPF program loading APIs
(mostly bpf_load_program_xattr(), but also some bpf_verify_program()) to
bpf_prog_load() uses.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211103220845.2676888-10-andrii@kernel.org

selftests/bpf: Rewrite recvmsg{4,6} asm progs to c in test_sock_addr

I'll extend them in the next patch. It's easier to work with C
than with asm.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210127232853.3753823-4-sdf@google.com

selftests/bpf: Rewrite test_sock_addr bind bpf into C

I'm planning to extend it in the next patches. It's much easier to
work with C than BPF assembly.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201202172516.3483656-2-sdf@google.com

bpf, selftests: Use single cgroup helpers for both test_sockmap/progs

Nearly every user of cgroup helpers does the same sequence of API calls. So
push these into a single helper cgroup_setup_and_join. The cases that do
a bit of extra logic are test_progs which currently uses an env variable
to decide if it needs to setup the cgroup environment or can use an
existingi environment. And then tests that are doing cgroup tests
themselves. We skip these cases for now.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/159623335418.30208.15807461815525100199.stgit@john-XPS-13-9370

selftests/bpf: Test narrow loads for bpf_sock_addr.user_port

Test 1,2,4-byte loads from bpf_sock_addr.user_port in sock_addr
programs.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/e5c734a58cca4041ab30cb5471e644246f8cdb5a.1589420814.git.rdna@fb.com

bpf: more msg_name rewrite tests to test_sock_addr

Extend test_sock_addr for recvmsg test cases, bigger parts of the
sendmsg code can be reused for this. Below are the strace view of
the recvmsg rewrites; the sendmsg side does not have a BPF prog
connected to it for the context of this test:

IPv4 test case:

[pid 4846] bpf(BPF_PROG_ATTACH, {target_fd=3, attach_bpf_fd=4, attach_type=0x13 /* BPF_??? */, attach_flags=BPF_F_ALLOW_OVERRIDE}, 112) = 0
[pid 4846] socket(AF_INET, SOCK_DGRAM, IPPROTO_IP) = 5
[pid 4846] bind(5, {sa_family=AF_INET, sin_port=htons(4444), sin_addr=inet_addr("127.0.0.1")}, 128) = 0
[pid 4846] socket(AF_INET, SOCK_DGRAM, IPPROTO_IP) = 6
[pid 4846] sendmsg(6, {msg_name={sa_family=AF_INET, sin_port=htons(4444), sin_addr=inet_addr("127.0.0.1")}, msg_namelen=128, msg_iov=[{iov_base="a", iov_len=1}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 1
[pid 4846] select(6, [5], NULL, NULL, {tv_sec=2, tv_usec=0}) = 1 (in [5], left {tv_sec=1, tv_usec=999995})
[pid 4846] recvmsg(5, {msg_name={sa_family=AF_INET, sin_port=htons(4040), sin_addr=inet_addr("192.168.1.254")}, msg_namelen=128->16, msg_iov=[{iov_base="a", iov_len=64}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 1
[pid 4846] close(6) = 0
[pid 4846] close(5) = 0
[pid 4846] bpf(BPF_PROG_DETACH, {target_fd=3, attach_type=0x13 /* BPF_??? */}, 112) = 0

IPv6 test case:

[pid 4846] bpf(BPF_PROG_ATTACH, {target_fd=3, attach_bpf_fd=4, attach_type=0x14 /* BPF_??? */, attach_flags=BPF_F_ALLOW_OVERRIDE}, 112) = 0
[pid 4846] socket(AF_INET6, SOCK_DGRAM, IPPROTO_IP) = 5
[pid 4846] bind(5, {sa_family=AF_INET6, sin6_port=htons(6666), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, 128) = 0
[pid 4846] socket(AF_INET6, SOCK_DGRAM, IPPROTO_IP) = 6
[pid 4846] sendmsg(6, {msg_name={sa_family=AF_INET6, sin6_port=htons(6666), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, msg_namelen=128, msg_iov=[{iov_base="a", iov_len=1}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 1
[pid 4846] select(6, [5], NULL, NULL, {tv_sec=2, tv_usec=0}) = 1 (in [5], left {tv_sec=1, tv_usec=999996})
[pid 4846] recvmsg(5, {msg_name={sa_family=AF_INET6, sin6_port=htons(6060), inet_pton(AF_INET6, "face:b00c:1234:5678::abcd", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, msg_namelen=128->28, msg_iov=[{iov_base="a", iov_len=64}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 1
[pid 4846] close(6) = 0
[pid 4846] close(5) = 0
[pid 4846] bpf(BPF_PROG_DETACH, {target_fd=3, attach_type=0x14 /* BPF_??? */}, 112) = 0

test_sock_addr run w/o strace view:

# ./test_sock_addr.sh
[...]
Test case: recvmsg4: return code ok .. [PASS]
Test case: recvmsg4: return code !ok .. [PASS]
Test case: recvmsg6: return code ok .. [PASS]
Test case: recvmsg6: return code !ok .. [PASS]
Test case: recvmsg4: rewrite IP & port (asm) .. [PASS]
Test case: recvmsg6: rewrite IP & port (asm) .. [PASS]
[...]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests: bpf: enable hi32 randomization for all tests

The previous libbpf patch allows user to specify "prog_flags" to bpf
program load APIs. To enable high 32-bit randomization for a test, we need
to set BPF_F_TEST_RND_HI32 in "prog_flags".

To enable such randomization for all tests, we need to make sure all places
are passing BPF_F_TEST_RND_HI32. Changing them one by one is not
convenient, also, it would be better if a test could be switched to
"normal" running mode without code change.

Given the program load APIs used across bpf selftests are mostly:
bpf_prog_load: load from file
bpf_load_program: load from raw insns

A test_stub.c is implemented for bpf seltests, it offers two functions for
testing purpose:

bpf_prog_test_load
bpf_test_load_program

The are the same as "bpf_prog_load" and "bpf_load_program", except they
also set BPF_F_TEST_RND_HI32. Given *_xattr functions are the APIs to
customize any "prog_flags", it makes little sense to put these two
functions into libbpf.

Then, the following CFLAGS are passed to compilations for host programs:
-Dbpf_prog_load=bpf_prog_test_load
-Dbpf_load_program=bpf_test_load_program

They migrate the used load APIs to the test version, hence enable high
32-bit randomization for these tests without changing source code.

Besides all these, there are several testcases are using
"bpf_prog_load_attr" directly, their call sites are updated to pass
BPF_F_TEST_RND_HI32.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: fix incorrect users of create_and_get_cgroup

We have some tests that assume create_and_get_cgroup returns -1 on error
which is incorrect (it returns 0 on error). Since fd might be zero in
general case, change create_and_get_cgroup to return -1 on error
and fix the users that assume 0 on error.

Fixes: f269099a7e7a ("tools/bpf: add a selftest for bpf_get_current_cgroup_id() helper")
Fixes: 7d2c6cfc5411 ("bpf: use --cgroup in test_suite if supplied")

v2:
- instead of fixing the uses that assume -1 on error, convert the users
that assume 0 on error (fd might be zero in general case)

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Test [::] -> [::1] rewrite in sys_sendmsg in test_sock_addr

Test that sys_sendmsg BPF hook doesn't break sys_sendmsg behaviour to
rewrite destination IPv6 = [::] with [::1] (BSD'ism).

Two test cases are added:

1) User passes dst IPv6 = [::] and BPF_CGROUP_UDP6_SENDMSG program
doesn't touch it.

2) User passes dst IPv6 != [::], but BPF_CGROUP_UDP6_SENDMSG program
rewrites it with [::].

In both cases [::1] is used by sys_sendmsg code eventually and datagram
is sent successfully for unconnected UDP socket.

Example of relevant output:
Test case: sendmsg6: set dst IP = [::] (BSD'ism) .. [PASS]
Test case: sendmsg6: preserve dst IP = [::] (BSD'ism) .. [PASS]

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Test narrow loads with off > 0 for bpf_sock_addr

Add more test cases for context bpf_sock_addr to test narrow loads with
offset > 0 for ctx->user_ip4 field (__u32):
* off=1, size=1;
* off=2, size=1;
* off=3, size=1;
* off=2, size=2.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

bpf: Refactor ARRAY_SIZE macro to bpf_util.h

This patch refactors the ARRAY_SIZE macro to bpf_util.h.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

selftests/bpf: Test sys_connect BPF hooks with TFO

TCP Fast Open is triggered by sys_sendmsg with MSG_FASTOPEN flag for
SOCK_STREAM socket.

Even though it's sys_sendmsg, it eventually calls __inet_stream_connect
the same way sys_connect does for TCP. __inet_stream_connect, in turn,
already has BPF hooks for sys_connect.

That means TFO is already covered by BPF_CGROUP_INET{4,6}_CONNECT and
the only missing piece is selftest. The patch adds selftest for TFO.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

selftests/bpf: Selftest for sys_sendmsg hooks

Add selftest for BPF_CGROUP_UDP4_SENDMSG and BPF_CGROUP_UDP6_SENDMSG
attach types.

Try to sendmsg(2) to specific IP:port and test that:
* source IP is overridden as expected.
* remote IP:port pair is overridden as expected;

Both UDPv4 and UDPv6 are tested.

Output:
# test_sock_addr.sh 2>/dev/null
Wait for testing IPv4/IPv6 to become available ... OK
... pre-existing test-cases skipped ...
Test case: sendmsg4: load prog with wrong expected attach type .. [PASS]
Test case: sendmsg4: attach prog with wrong attach type .. [PASS]
Test case: sendmsg4: rewrite IP & port (asm) .. [PASS]
Test case: sendmsg4: rewrite IP & port (C) .. [PASS]
Test case: sendmsg4: deny call .. [PASS]
Test case: sendmsg6: load prog with wrong expected attach type .. [PASS]
Test case: sendmsg6: attach prog with wrong attach type .. [PASS]
Test case: sendmsg6: rewrite IP & port (asm) .. [PASS]
Test case: sendmsg6: rewrite IP & port (C) .. [PASS]
Test case: sendmsg6: IPv4-mapped IPv6 .. [PASS]
Test case: sendmsg6: deny call .. [PASS]
Summary: 27 PASSED, 0 FAILED

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

selftests/bpf: Prepare test_sock_addr for extension

test_sock_addr was not easy to extend since it was focused on sys_bind
and sys_connect quite a bit.

Reorganized it so that it'll be easier to cover new test-cases for
`BPF_PROG_TYPE_CGROUP_SOCK_ADDR`:

- decouple test-cases so that only one BPF prog is tested at a time;

- check programmatically that local IP:port for sys_bind, source IP and
destination IP:port for sys_connect are rewritten property by tested
BPF programs.

The output of new version:
# test_sock_addr.sh 2>/dev/null
Wait for testing IPv4/IPv6 to become available ... OK
Test case: bind4: load prog with wrong expected attach type .. [PASS]
Test case: bind4: attach prog with wrong attach type .. [PASS]
Test case: bind4: rewrite IP & TCP port in .. [PASS]
Test case: bind4: rewrite IP & UDP port in .. [PASS]
Test case: bind6: load prog with wrong expected attach type .. [PASS]
Test case: bind6: attach prog with wrong attach type .. [PASS]
Test case: bind6: rewrite IP & TCP port in .. [PASS]
Test case: bind6: rewrite IP & UDP port in .. [PASS]
Test case: connect4: load prog with wrong expected attach type .. [PASS]
Test case: connect4: attach prog with wrong attach type .. [PASS]
Test case: connect4: rewrite IP & TCP port .. [PASS]
Test case: connect4: rewrite IP & UDP port .. [PASS]
Test case: connect6: load prog with wrong expected attach type .. [PASS]
Test case: connect6: attach prog with wrong attach type .. [PASS]
Test case: connect6: rewrite IP & TCP port .. [PASS]
Test case: connect6: rewrite IP & UDP port .. [PASS]
Summary: 16 PASSED, 0 FAILED

(stderr contains errors from libbpf when testing load/attach with
invalid arguments)

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/bpf: fix test_sock and test_sock_addr.sh failure

The bpf selftests test_sock and test_sock_addr.sh failed
in my test machine. The failure looks like:
$ ./test_sock
Test case: bind4 load with invalid access: src_ip6 .. [PASS]
Test case: bind4 load with invalid access: mark .. [PASS]
Test case: bind6 load with invalid access: src_ip4 .. [PASS]
Test case: sock_create load with invalid access: src_port .. [PASS]
Test case: sock_create load w/o expected_attach_type (compat mode) .. [FAIL]
Test case: sock_create load w/ expected_attach_type .. [FAIL]
Test case: attach type mismatch bind4 vs bind6 .. [FAIL]
...
Summary: 4 PASSED, 12 FAILED
$ ./test_sock_addr.sh
Wait for testing IPv4/IPv6 to become available .....
ERROR: Timeout waiting for test IP to become available.

In test_sock, bpf program loads failed due to hitting memlock limits.
In test_sock_addr.sh, my test machine is a ipv6 only test box and using
"ping" without specifying address family for an ipv6 address does not work.

This patch fixed the issue by including header bpf_rlimit.h in test_sock.c
and test_sock_addr.c, and specifying address family for ping command.

Cc: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

selftests/bpf: Selftest for sys_connect hooks

Add selftest for BPF_CGROUP_INET4_CONNECT and BPF_CGROUP_INET6_CONNECT
attach types.

Try to connect(2) to specified IP:port and test that:
* remote IP:port pair is overridden;
* local end of connection is bound to specified IP.

All combinations of IPv4/IPv6 and TCP/UDP are tested.

Example:
# tcpdump -pn -i lo -w connect.pcap 2>/dev/null &
[1] 478
# strace -qqf -e connect -o connect.trace ./test_sock_addr.sh
Wait for testing IPv4/IPv6 to become available ... OK
Load bind4 with invalid type (can pollute stderr) ... REJECTED
Load bind4 with valid type ... OK
Attach bind4 with invalid type ... REJECTED
Attach bind4 with valid type ... OK
Load connect4 with invalid type (can pollute stderr) libbpf: load bpf \
program failed: Permission denied
libbpf: -- BEGIN DUMP LOG ---
libbpf:
0: (b7) r2 = 23569
1: (63) *(u32 *)(r1 +24) = r2
2: (b7) r2 = 16777343
3: (63) *(u32 *)(r1 +4) = r2
invalid bpf_context access off=4 size=4
[ 1518.404609] random: crng init done

libbpf: -- END LOG --
libbpf: failed to load program 'cgroup/connect4'
libbpf: failed to load object './connect4_prog.o'
... REJECTED
Load connect4 with valid type ... OK
Attach connect4 with invalid type ... REJECTED
Attach connect4 with valid type ... OK
Test case #1 (IPv4/TCP):
Requested: bind(192.168.1.254, 4040) ..
Actual: bind(127.0.0.1, 4444)
Requested: connect(192.168.1.254, 4040) from (*, *) ..
Actual: connect(127.0.0.1, 4444) from (127.0.0.4, 56068)
Test case #2 (IPv4/UDP):
Requested: bind(192.168.1.254, 4040) ..
Actual: bind(127.0.0.1, 4444)
Requested: connect(192.168.1.254, 4040) from (*, *) ..
Actual: connect(127.0.0.1, 4444) from (127.0.0.4, 56447)
Load bind6 with invalid type (can pollute stderr) ... REJECTED
Load bind6 with valid type ... OK
Attach bind6 with invalid type ... REJECTED
Attach bind6 with valid type ... OK
Load connect6 with invalid type (can pollute stderr) libbpf: load bpf \
program failed: Permission denied
libbpf: -- BEGIN DUMP LOG ---
libbpf:
0: (b7) r6 = 0
1: (63) *(u32 *)(r1 +12) = r6
invalid bpf_context access off=12 size=4

libbpf: -- END LOG --
libbpf: failed to load program 'cgroup/connect6'
libbpf: failed to load object './connect6_prog.o'
... REJECTED
Load connect6 with valid type ... OK
Attach connect6 with invalid type ... REJECTED
Attach connect6 with valid type ... OK
Test case #3 (IPv6/TCP):
Requested: bind(face:b00c:1234:5678::abcd, 6060) ..
Actual: bind(::1, 6666)
Requested: connect(face:b00c:1234:5678::abcd, 6060) from (*, *)
Actual: connect(::1, 6666) from (::6, 37458)
Test case #4 (IPv6/UDP):
Requested: bind(face:b00c:1234:5678::abcd, 6060) ..
Actual: bind(::1, 6666)
Requested: connect(face:b00c:1234:5678::abcd, 6060) from (*, *)
Actual: connect(::1, 6666) from (::6, 39315)
### SUCCESS
# egrep 'connect\(.*AF_INET' connect.trace | \
> egrep -vw 'htons\(1025\)' | fold -b -s -w 72
502 connect(7, {sa_family=AF_INET, sin_port=htons(4040),
sin_addr=inet_addr("192.168.1.254")}, 128) = 0
502 connect(8, {sa_family=AF_INET, sin_port=htons(4040),
sin_addr=inet_addr("192.168.1.254")}, 128) = 0
502 connect(9, {sa_family=AF_INET6, sin6_port=htons(6060),
inet_pton(AF_INET6, "face:b00c:1234:5678::abcd", &sin6_addr),
sin6_flowinfo=0, sin6_scope_id=0}, 128) = 0
502 connect(10, {sa_family=AF_INET6, sin6_port=htons(6060),
inet_pton(AF_INET6, "face:b00c:1234:5678::abcd", &sin6_addr),
sin6_flowinfo=0, sin6_scope_id=0}, 128) = 0
# fg
tcpdump -pn -i lo -w connect.pcap 2> /dev/null
# tcpdump -r connect.pcap -n tcp | cut -c 1-72
reading from file connect.pcap, link-type EN10MB (Ethernet)
17:57:40.383533 IP 127.0.0.4.56068 > 127.0.0.1.4444: Flags [S], seq 1333
17:57:40.383566 IP 127.0.0.1.4444 > 127.0.0.4.56068: Flags [S.], seq 112
17:57:40.383589 IP 127.0.0.4.56068 > 127.0.0.1.4444: Flags [.], ack 1, w
17:57:40.384578 IP 127.0.0.1.4444 > 127.0.0.4.56068: Flags [R.], seq 1,
17:57:40.403327 IP6 ::6.37458 > ::1.6666: Flags [S], seq 406513443, win
17:57:40.403357 IP6 ::1.6666 > ::6.37458: Flags [S.], seq 2448389240, ac
17:57:40.403376 IP6 ::6.37458 > ::1.6666: Flags [.], ack 1, win 342, opt
17:57:40.404263 IP6 ::1.6666 > ::6.37458: Flags [R.], seq 1, ack 1, win

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

selftests/bpf: Selftest for sys_bind hooks

Add selftest to work with bpf_sock_addr context from
`BPF_PROG_TYPE_CGROUP_SOCK_ADDR` programs.

Try to bind(2) on IP:port and apply:
* loads to make sure context can be read correctly, including narrow
loads (byte, half) for IP and full-size loads (word) for all fields;
* stores to those fields allowed by verifier.

All combination from IPv4/IPv6 and TCP/UDP are tested.

Both scenarios are tested:
* valid programs can be loaded and attached;
* invalid programs can be neither loaded nor attached.

Test passes when expected data can be read from context in the
BPF-program, and after the call to bind(2) socket is bound to IP:port
pair that was written by BPF-program to the context.

Example:
# ./test_sock_addr
Attached bind4 program.
Test case #1 (IPv4/TCP):
Requested: bind(192.168.1.254, 4040) ..
Actual: bind(127.0.0.1, 4444)
Test case #2 (IPv4/UDP):
Requested: bind(192.168.1.254, 4040) ..
Actual: bind(127.0.0.1, 4444)
Attached bind6 program.
Test case #3 (IPv6/TCP):
Requested: bind(face:b00c:1234:5678::abcd, 6060) ..
Actual: bind(::1, 6666)
Test case #4 (IPv6/UDP):
Requested: bind(face:b00c:1234:5678::abcd, 6060) ..
Actual: bind(::1, 6666)
### SUCCESS

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>