Re: [PATCH testsuite 3/3] travis: test building the test policy package

[Ondrej Mosnacek <omosnace@redhat.com>]

On Mon, Sep 30, 2019 at 3:44 PM Stephen Smalley <sds@tycho.nsa.gov> wrote:
> On 9/30/19 6:48 AM, Ondrej Mosnacek wrote:
> > Download, build, and install Fedora policy & refpolicy and try building
> > the test policy package against both of them.
>
> I guess this is a necessary first step to actually getting the testsuite
> to run on travis, which would be the more important goal.  That
> obviously requires actually enabling SELinux on bionic, unless we could
> get travis-ci to offer fedora or centos images.
>
> >
> > Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> > ---
> >   .travis.yml                         | 24 ++++++++++++++++++--
> >   travis-ci/enable-policy.sh          | 10 +++++++++
> >   travis-ci/setup-policy-fedora.sh    | 35 +++++++++++++++++++++++++++++
> >   travis-ci/setup-policy-refpolicy.sh | 22 ++++++++++++++++++
> >   4 files changed, 89 insertions(+), 2 deletions(-)
> >   create mode 100644 travis-ci/enable-policy.sh
> >   create mode 100644 travis-ci/setup-policy-fedora.sh
> >   create mode 100644 travis-ci/setup-policy-refpolicy.sh
> >
> > diff --git a/.travis.yml b/.travis.yml
> > index fbbe98d..c8cd44e 100644
> > --- a/.travis.yml
> > +++ b/.travis.yml
> > @@ -1,6 +1,6 @@
> >   language: c
> >
> > -dist: xenial
> > +dist: bionic
> >
> >   addons:
> >     apt:
> > @@ -8,6 +8,14 @@ addons:
> >         - astyle
> >         - libselinux1-dev
> >         - libsctp-dev
> > +      - checkpolicy
> > +      - semodule-utils
> > +
> > +cache:
> > +  directories:
> > +    - selinux-policy
> > +    - container-selinux
> > +    - refpolicy
> >
> >   before_install:
> >     # FYI: known good with HEAD at 8551fc60fc515cd290ba38ee8c758c1f4df52b56
> > @@ -17,7 +25,19 @@ before_install:
> >        perl Makefile.PL &&
> >        make &&
> >        sudo make install)
> > +  # install libbpf from sources
> > +  - git clone https://github.com/libbpf/libbpf
> > +  - (cd libbpf/src && make PREFIX=/usr/local)
> > +  - (cd libbpf/src && sudo make install PREFIX=/usr/local)
>
> Not packaged on bionic or not recent enough?

Not packaged, AFAICT.

>
> > +  # install Fedora policy and refpolicy
> > +  - bash travis-ci/setup-policy-fedora.sh
> > +  - bash travis-ci/setup-policy-refpolicy.sh
> > +  # establish a fake "selinuxfs" mount (policy/Makefile just greps for selinuxfs)
> > +  - sudo mkdir -p /tmp/fake-selinuxfs
> > +  - sudo mount -t tmpfs tmpfs /tmp/fake-selinuxfs
> > +  - echo 31 >/tmp/fake-selinuxfs/policyvers
>
> Fragile; maybe use checkpolicy -V | awk '{print $1}' or equivalent?

This will get the policy version that checkpolicy supports, but the
policy Makefile also checks the version supported by the running
kernel. Since the policy won't actually be loaded in this case, it
makes sense to just report the highest known version so that the
Makefile tries to build as much as it can with the checkpolicy it has.
On second thought, we might even put in just some "infinity" number
(e.g. 999), since it should be just an additional upper bound to the
checkpolicy upper bound.

>
> >
> >   script:
> >     - tools/check-syntax -f && git diff --exit-code
> > -  - make
> > +  - bash travis-ci/enable-policy.sh targeted  && make POLDEV=/usr/share/selinux/targeted
> > +  - bash travis-ci/enable-policy.sh refpolicy && make POLDEV=/usr/share/selinux/refpolicy
> > diff --git a/travis-ci/enable-policy.sh b/travis-ci/enable-policy.sh
> > new file mode 100644
> > index 0000000..ae53fbe
> > --- /dev/null
> > +++ b/travis-ci/enable-policy.sh
> > @@ -0,0 +1,10 @@
> > +#!/bin/bash
> > +
> > +set -e
> > +
> > +# create a dummy /etc/selinux/config
> > +sudo mkdir -p /etc/selinux
> > +sudo tee /etc/selinux/config >/dev/null <<EOF
> > +SELINUX=disabled
> > +SELINUXTYPE=$1
> > +EOF
> > diff --git a/travis-ci/setup-policy-fedora.sh b/travis-ci/setup-policy-fedora.sh
> > new file mode 100644
> > index 0000000..192e234
> > --- /dev/null
> > +++ b/travis-ci/setup-policy-fedora.sh
> > @@ -0,0 +1,35 @@
> > +#!/bin/bash
> > +
> > +set -ex
> > +
> > +if ! [ -d selinux-policy/.git ]; then
> > +     git clone --recursive https://github.com/fedora-selinux/selinux-policy
> > +     (cd selinux-policy/policy/modules/contrib && git checkout rawhide)
> > +else
> > +     (cd selinux-policy && git pull || { git checkout '*' && git pull; })
> > +     (cd selinux-policy/policy/modules/contrib && git pull)
> > +fi
> > +
> > +if ! [ -d container-selinux/.git ]; then
> > +     git clone https://github.com/containers/container-selinux.git
> > +     for f in container.if container.te; do
> > +             ln -s ../../../../container-selinux/$f \
> > +                     selinux-policy/policy/modules/contrib/$f
> > +     done
> > +else
> > +     (cd container-selinux && git pull)
> > +fi
>
> Seem brittle / tightly tied to fedora policy internals - is there some
> more general facility or perhaps they even provide a script for doing
> this that we could just reuse?

No, this is simply how the Fedora policy repos are structured. I
mostly mirrored the logic of .travis.yml from the main repo [1] I
don't think there's a better way to do this.

[1] https://github.com/fedora-selinux/selinux-policy/

>
> > +
> > +cd selinux-policy
> > +
> > +grep -q refpolicy build.conf && sed -i 's/refpolicy/targeted/' build.conf
> > +grep -q '^portcon sctp' policy/modules/kernel/corenetwork.te.in && \
> > +     sed -i '/^portcon sctp/d' policy/modules/kernel/corenetwork.te.in
>
> Is this a limitation of the checkpolicy packaged in bionic?  If so,

Yes, I think it is due to checkpolicy/-module being too old. Maybe it
should actually be handled in policy/Makefile with a [MOD_]POL_VERS
check... I'll need to look more carefully into this.

> should we just grab the upstream selinux userspace and build it ourselves?

I tried to keep the number of dynamic dependencies on the minimum, but
perhaps that's indeed the better way to go here...

>
> > +
> > +[ -f policy/modules.conf ] || make conf
> > +
> > +make -j`nproc --all`
> > +sudo make install install-headers
> > +
> > +# workaround for different Makefile location in Fedora RPMs
> > +sudo ln -s include/Makefile /usr/share/selinux/targeted/Makefile
> > diff --git a/travis-ci/setup-policy-refpolicy.sh b/travis-ci/setup-policy-refpolicy.sh
> > new file mode 100644
> > index 0000000..d89b041
> > --- /dev/null
> > +++ b/travis-ci/setup-policy-refpolicy.sh
> > @@ -0,0 +1,22 @@
> > +#!/bin/bash
> > +
> > +set -ex
> > +
> > +if ! [ -d refpolicy/.git ]; then
> > +     git clone https://github.com/SELinuxProject/refpolicy
> > +else
> > +     git pull || { git checkout '*' && git pull; }
> > +fi
> > +
> > +cd refpolicy
> > +
> > +[ -f policy/modules.conf ] || make conf
> > +
> > +grep -q '^portcon sctp' policy/modules/kernel/corenetwork.te.in && \
> > +     sed -i '/^portcon sctp/d' policy/modules/kernel/corenetwork.te.in
> > +
> > +make -j`nproc --all`
> > +sudo make install install-headers
> > +
> > +# workaround for different Makefile location in Fedora RPMs
> > +sudo ln -s include/Makefile /usr/share/selinux/refpolicy/Makefile
> >
>

-- 
Ondrej Mosnacek <omosnace at redhat dot com>
Software Engineer, Security Technologies
Red Hat, Inc.