wireguard: selftests: set fake real time in init

Not all platforms have an RTC, and rather than trying to force one into
each, it's much easier to just set a fixed time. This is necessary
because WireGuard's latest handshakes parameter is returned in wallclock
time, and if the system time isn't set, and the system is really fast,
then this returns 0, which trips the test.

Turning this on requires setting CONFIG_COMPAT_32BIT_TIME=y, as musl
doesn't support settimeofday without it.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

wireguard: selftests: use maximum cpu features and allow rng seeding

By forcing the maximum CPU that QEMU has available, we expose additional
capabilities, such as the RNDR instruction, which increases test
coverage. This then allows the CI to skip the fake seeding step in some
cases. Also enable STRICT_KERNEL_RWX to catch issues related to early
jump labels when the RNG is initialized at boot.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

wireguard: selftests: set panic_on_warn=1 from cmdline

Rather than setting this once init is running, set panic_on_warn from
the kernel command line, so that it catches splats from WireGuard
initialization code and the various crypto selftests.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

wireguard: selftests: simplify RNG seeding

The seed_rng() function was written to work across lots of old kernels,
back when WireGuard used a big compatibility layer. Now that things have
evolved, we can vastly simplify this, by just marking the RNG as seeded.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

wireguard: selftests: remove duplicated include <sys/types.h>

This commit removes a duplicated include.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

wireguard: selftests: remove ancient kernel compatibility code

Quite a bit of the test suite was designed to work with ancient kernels.
Thankfully we no longer have to deal with this. This commit updates
things that we can finally update and removes things that we can finally
remove, to avoid the build-up of the last several years as a result of
having to support ancient kernels. We can finally rely on suppress_
prefixlength being available. On the build side of things, the no-PIE
hack is no longer required, and we can bump some of the tools, repair
our m68k and i686-kvm support, and get better coverage of the static
branches used in the crypto lib and in udp_tunnel.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

wireguard: selftests: import harness makefile for test suite

WireGuard has been using this on build.wireguard.com for the last
several years with considerable success. It allows for very quick and
iterative development cycles, and supports several platforms.

To run the test suite on your current platform in QEMU:

$ make -C tools/testing/selftests/wireguard/qemu -j$(nproc)

To run it with KASAN and such turned on:

$ DEBUG_KERNEL=yes make -C tools/testing/selftests/wireguard/qemu -j$(nproc)

To run it emulated for another platform in QEMU:

$ ARCH=arm make -C tools/testing/selftests/wireguard/qemu -j$(nproc)

At the moment, we support aarch64_be, aarch64, arm, armeb, i686, m68k,
mips64, mips64el, mips, mipsel, powerpc64le, powerpc, and x86_64.

The system supports incremental rebuilding, so it should be very fast to
change a single file and then test it out and have immediate feedback.

This requires for the right toolchain and qemu to be installed prior.
I've had success with those from musl.cc.

This is tailored for WireGuard at the moment, though later projects
might generalize it for other network testing.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>