When applying labels inside the container that are unknown to the
host, the process needs to have the CAP_MAC_ADMIN capability in order
to do so, otherwise the kernel will prevent setting those unknown
labels. See the previous commit for more details.
Drop the `kwargs` forwarding from buildroot.run() to subprocess.run().
We do not use it other than for `stdin=subprocess.DEVNULL`. Set that
option directly instead.
Doing the kwargs forwarding mixes the argument namespaces and is very
hard to read. It is not clear from the call-site which argument goes to
buildroot.run() and which to subprocess.run().
Lastly, it requires us to manually fetch `check` just to make pylint
happy. Lets just drop this dance and make the API explicit.
This reverts commit 33844711cd.
There are systems were our runners have no standard python3 location
available. They will fix the environment before invoking any further
utilities. Therefore, we cannot rely on `python3 foo.py` to work in our
ad-hoc containers.
This simply reverts the behavior back to using the shebang.
Prepare the PYTHONPATH of the build-root container to include the path
to the osbuild library. This way, we no longer need any symlinks or
bind-mounts for the individual modules.
Use the python-interpreter explicitly to invoke the runners. This works
around inconsistencies between scripts imported from the host, and the
interpreter taken from a build-root.
With `--keep-unit` we now run with the privileges and resources of the
caller. We no longer require external services to extend our privileges.
This also means we no longer have to configure our unit sandbox
manually, but simply rely on kernel sandboxing to do the right thing.
This adds one more flags to `systemd-nspawn`:
--keep-unit
This prevents nspawn from creating its own scope unit and
instead uses the scope of the caller. Since we want nspawn to
run with the privileges of the caller, this is fitting for our
use case.
Furthermore, this makes nspawn work without a running system
bus, since it no longer needs to talk to systemd pid1.
(introduced with systemd-v209)
With this in place, osbuild can be run from within docker containers (or
other containers without systemd as pid1). This still requires some
extra setup, but this can all be done in the container manager.
Two cleanups for the context-managers we use:
* Use `contextlib.AbstractContextManager` if possible. This class
simply provides a default `__enter__` implementation which just
returns `self`. So use it where applicable.
Additionally, it provides an abstract `__exit__` method and thus
allows static checks for an existance of `__exit__` in the dependent
class. We might use that everywhere, but this is a separate
decision, so not included here.
* Explicitly return `None` from `__exit__`. The python docs state:
If an exception is supplied, and the method wishes to suppress
the exception (i.e., prevent it from being propagated), it
should return a true value. Otherwise, the exception will be
processed normally upon exit from this method.
That is, unless we want exceptions to be suppressed, we should
never return a `truthy` value. The python contextlib suggest using
`None` as a default return value, so lets just do that.
In particular, the explicit `return exc_type is None` that we use
has no effect at all, since it only returns `True` if no exception
was raised.
This commit cleans this up and just follows what the `contextlib`
module does and returns None everywhere (well, it returns nothing
which apparently is the same as returning `None` in python). It is
unlikely that we ever want to suppress any exceptions, anyway.
We want to run stages and other scripts inside of the nspawn containers
we use to build pipelines. Since our pipelines are meant to be
self-contained, this should imply that the build-root must have osbuild
installed. However, this has not been the case so far for several
reasons including:
1. OSBuild is not packaged for all the build-roots we want to support
and thus we have the chicken-and-egg problem.
2. During testing and development, we want to support using a local
`libdir`.
3. We already provide an API to the container. Importing scripts from
the outside just makes this API bigger, but does not change the
fact that build-roots are not self-contained. Same is true for the
running kernel, and probably much more..
With all this in mind, our strategy probably still is to eventually
package osbuild for the build-root. This would significantly reduce our
API exposure, points-of-failure, and host-reliance. However, this switch
might still be some weeks out.
With this in mind, though, we can expect the ideal setup to have a full
osbuild available in the build-root. Hence, any script we import so far
should be able to access the entire `libdir`. This commit unifies the
libdir handling by installing the symlinks into `libdir` and providing
a single bind-mount of the module-path into `libdir`.
We can always decide to scratch that in the future when we scratch the
libdir-import from the host-root. Until then, I believe this commit
nicely unifies the way we import the module both in a local checkout as
well as in the container.
Add /boot to be mounted from the build tree into the build root,
because the EFI binaries for grub are stored in there and for
ostree grub2 support those need to be copied too.
Currently /var was always backed by /var/tmp, but we may want to
control exactly what it is backed by. The default is the same, so
this is not a behavioral change.
The z Initial Program Loader (zipl) when creating the bootmap in
bootmap_creat (src/zipl/bootmap.c) wants to create a device node
via misc_temp_dev (bootmap_create:1141) for the device that it
is installing the bootloader to[1]. Currently access to loopback
devices is allowed from within the container (it is used to mount
the image), but only read/write access. On s390x also allow the
creation of device nodes, so zipl can do its work and install
the bootloader stages on the "disk".
[1] zipl source at commit dcce14923c3e9615df53773d1d8a3a22cbb23b96
This might (hopefully) fix a race in destructing the asyncio.EventLoop
that's used in all API classes, which leads to warnings about unhandled
exceptions on CI.
This also puts their creation closer to where the client-side sockets
are created.
The workaround of manually linking /lib64 -> /usr/lib64 inside the
container that is needed on s390 is also required on ppc64 because
here the dynamic linker is set to /lib64/ld64.so.2 and the /lib64
link is not created.
Work around a combination of systemd not creating the link from
/lib64 -> /usr/lib64 (see systemd issue #14311) and the dynamic
linker is being set to (/lib/ld64.so.1 -> /lib64/ld64.so.1)
Therefore we manually create the link before calling nspawn
We've been using a generic `osbuild-run`, which sets up the build
environment (and works around bugs) for all build roots. It is already
getting unwieldy, because it tries to detect the OS for some things it
configures. It's also about to cause problems for RHEL, which doesn't
currently support a python3 shebang without having /etc around.
This patch changes the `build` key in a pipeline to not be a pipeline
itself, but an object with `runner` and `pipeline` keys. `pipeline` is
the build pipeline, as before. `runner` is the name of the runner to
use. Runners are programs in the `runners` subdirectory.
Three runners are included in this patch. They're copies of osbuild-run
for now (except some additions for rhel82). The idea is that each of
them only contains the minimal setup code necessary for an OS, and that
we can review what's needed when updating a build root.
Also modify the `--build-pipeline` command line switch to accept such a
build object (instead of a pipeline) and rename it accordingly, to
`--build-env`.
Correspondingly, `OSBUILD_TEST_BUILD_PIPELINE` → `OSBUILD_TEST_BUILD_ENV`.
`osbuild-run` sets up the build root so that programs can be run
correctly in it. It should be run for all programs, not just stages and
assemblers (even though they're the only consumers right now).
Also, conceptually, `osbuild-run` belongs to the build root. We'll
change its implementation based on the build root in a future commit.
The buildroot already sets up `/run/osbuild/api`. It makes sense to have
it manage libdir as well.
A nice side benefit of this is a simplification of the Stage and
Assembler classes, which grew quite complex and contained duplicate
code.
In BuildRoot a new mount /var pointing to temporary directory in host's
/var/tmp is created. This enables us to have temporary storage inside
the container which is not hosted on tmpfs. Thanks to that we can move
larger files out of the part of filesystem which is hosted on tmpfs to
save up memory on machines with low memory capacity.
Import modules between files using the syntax `from . import foobar`,
renaming what used to be `FooBar` to `foobar.FooBar` when moved to a
separate file.
In __init__.py only import what is meant to be public API.
Signed-off-by: Tom Gundersen <teg@jklm.no>
