Current tar implementation requires begin to be run as root about build HOT 6 CLOSED

ah, thanks for reminding me about this, I was intending to file an issue. I
think we should be able to just split this out and use ExtractTarChroot iff
euid == 0, and ExtractTar otherwise?

On Wed, Oct 14, 2015 at 11:12 AM, Derek Gonyeo [email protected]
wrote:

The ExpandTar function untars the ACI in a chroot, which requires root
permissions to set up.

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#35.

from build.

If a regular non-root user bob wants to build an ACI that contains files belonging to someone else than bob, the tar create/extract functions must be able to ignore the file ownership in the .acbuild directory, and instead acbuild must have a separate database of files' ownerships.

Basically this is what FakeRoot does but since we control the tar library from go, we don't need this kind of LD_PRELOAD trick.

The tar writer BuildWalker used by End already has a callback that can be used to change the files ownership in the tarball (added by appc/spec#498). But for the tar reader part (extract), I don't know if rkt/pkg/tar (rkt/rkt#1616) should grow this kind of feature or if it should be implemented directly in acbuild?

from build.

Also, ExpandTar can only extract to /: see how it is hardcoded: filepath.Join("/", hdr.Name). This is ok for rkt but does not really fit acbuild's requirements.

from build.

@alban my proposal here

from build.

@dgonyeo is this done now?

from build.

Nope, I still need to make a PR to make use of the new ExtractTarInsecure function. I'll get around to it in the near future.

from build.