While the v2 pull operation is writing the body of the layer blob to disk
it now computes the tarsum checksum of the archive before extracting it to
the backend storage driver. If the checksum does not match that from the
image manifest an error is raised.
Also adds more debug logging to the pull operation and fixes existing test
cases which were failing. Adds a reverse lookup constructor to the tarsum
package so that you can get a tarsum object using a checksum label.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
The current Dev version of TarSum includes hashing of extended
file attributes and omits inclusion of modified time headers.
I refactored the logic around the version differences to make it
more clear that the difference between versions is in how tar
headers are selected and ordered.
TarSum Version 1 is now declared with the new Dev version continuing
to track it.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
This introduces Versions for TarSum checksums.
Fixes: https://github.com/docker/docker/issues/7526
It preserves current functionality and abstracts the interface for
future flexibility of hashing algorithms. As a POC, the VersionDev
Tarsum does not include the mtime in the checksum calculation, and would
solve https://github.com/docker/docker/issues/7387 though this is not a
settled Version is subject to change until a version number is assigned.
Signed-off-by: Vincent Batts <vbatts@redhat.com>
