tests: Add test of PR_GET_SECCOMP

Check that the seccomp mode is 0 before doing anything
and is 2 after setting filter mode.

Can't check on a seccomp mode of 1 because strict mode
doesn't allow the prctl(2) call.

Signed-off-by: David Drysdale <drysdale@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
tests: validate pre-existing threads get nnp and filter

Makes sure that nnp gets set on threads getting TSYNCed.

Signed-off-by: David Drysdale <drysdale@google.com>
[added test for framework detecting lack of nnp]
Signed-off-by: Kees Cook <keescook@chromium.org>
tests: add run_tests target and .gitignore

In preparation for putting into upstream kernel tree, add targets.

Signed-off-by: David Drysdale <drysdale@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>