selftest: tcp: Add bind() tests for SO_REUSEADDR/SO_REUSEPORT.

This patch adds two tests using SO_REUSEADDR and SO_REUSEPORT and
defines errno for each test case.

SO_REUSEADDR/SO_REUSEPORT is set for the per-fixture two bind()
calls.

The notable pattern is the pair of v6only [::] and plain [::].
The two sockets are put into the same tb2, where per-bucket v6only
flag would be useless to detect bind() conflict.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240326204251.51301-9-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftest: tcp: Add bind() tests for IPV6_V6ONLY.

bhash2 was not well tested for IPv6-only sockets.

This patch adds test cases where we set IPV6_V6ONLY for per-fixture
bind() calls if variant->ipv6_only[i] is true.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240326204251.51301-8-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftest: tcp: Add more bind() calls.

In addtition to the two addresses defined in the fixtures, this patch
add 6 more bind calls():

* 0.0.0.0
* 127.0.0.1
* ::
* ::1
* ::ffff:0.0.0.0
* ::ffff:127.0.0.1

The first two per-fixture bind() calls control how inet_bind2_bucket
is created, and the rest 6 bind() calls cover as many conflicting
patterns as possible.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240326204251.51301-7-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftest: tcp: Add v4-v4 and v6-v6 bind() conflict tests.

We don't have bind() conflict tests for the same protocol pairs.

Let's add them except for the same address pair, which will be
covered by the following patch adding 6 more bind() calls for
each test case.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240326204251.51301-6-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftest: tcp: Define the reverse order bind() tests explicitly.

Currently, bind_wildcard.c calls bind() twice for two addresses and
checks the pre-defined errno against the 2nd call. Also, the two
bind() calls are swapped to cover various patterns how bind buckets
are created.

However, only testing two addresses is insufficient to detect regression.
So, we will add more bind() calls, and then, we need to define different
errno for each bind() per test case.

As a prepartion, let's define the reverse order bind() test cases as
fixtures.

No functional changes are intended.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240326204251.51301-5-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftest: tcp: Make bind() selftest flexible.

Currently, bind_wildcard.c tests only (IPv4, IPv6) pairs, but we will
add more tests for the same protocol pairs.

This patch makes it possible by changing the address pointer to void.

No functional changes are intended.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240326204251.51301-4-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftest: tcp: Add v4-mapped-v6 cases in bind_wildcard.c.

We add these 8 test cases in bind_wildcard.c to check bind() conflicts.

1st bind() 2nd bind()
--------- ---------
0.0.0.0 ::FFFF:0.0.0.0
::FFFF:0.0.0.0 0.0.0.0
0.0.0.0 ::FFFF:127.0.0.1
::FFFF:127.0.0.1 0.0.0.0
127.0.0.1 ::FFFF:0.0.0.0
::FFFF:0.0.0.0 127.0.0.1
127.0.0.1 ::FFFF:127.0.0.1
::FFFF:127.0.0.1 127.0.0.1

All test passed without bhash2 and with bhash2 and this series.

Before bhash2:
$ uname -r
6.0.0-rc1-00393-g0bf73255d3a3
$ ./bind_wildcard
...
# PASSED: 16 / 16 tests passed.

Just after bhash2:
$ uname -r
6.0.0-rc1-00394-g28044fc1d495
$ ./bind_wildcard
...
ok 15 bind_wildcard.v4_local_v6_v4mapped_local.v4_v6
not ok 16 bind_wildcard.v4_local_v6_v4mapped_local.v6_v4
# FAILED: 15 / 16 tests passed.

On net.git:
$ ./bind_wildcard
...
not ok 14 bind_wildcard.v4_local_v6_v4mapped_any.v6_v4
not ok 16 bind_wildcard.v4_local_v6_v4mapped_local.v6_v4
# FAILED: 13 / 16 tests passed.

With this series:
$ ./bind_wildcard
...
# PASSED: 16 / 16 tests passed.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftest: tcp: Move expected_errno into each test case in bind_wildcard.c.

This is a preparation patch for the following patch.

Let's define expected_errno in each test case so that we can add other test
cases easily.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftest: tcp: Fix address length in bind_wildcard.c.

The selftest passes the IPv6 address length for an IPv4 address.
We should pass the correct length.

Note inet_bind_sk() does not check if the size is larger than
sizeof(struct sockaddr_in), so there is no real bug in this
selftest.

Fixes: 13715acf8ab5 ("selftest: Add test for bind() conflicts.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftest: Add test for bind() conflicts.

The test checks if (IPv4, IPv6) address pair properly conflict or not.

* IPv4
* 0.0.0.0
* 127.0.0.1

* IPv6
* ::
* ::1

If the IPv6 address is [::], the second bind() always fails.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>