When opening an existing LUKS volume, if the iv generator is
essiv, then the iv hash algorithm is mandatory to provide. We
must report an error if it is omitted in the cipher mode spec,
not silently default to hash 0 (md5). If the iv generator is
not essiv, then we explicitly ignore any iv hash algorithm,
rather than report an error, for compatibility with dm-crypt.
When creating a new LUKS volume, if the iv generator is essiv
and no iv hsah algorithm is provided, we should default to
using the sha256 hash.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It is important that the QEMU luks implementation retains 100%
compatibility with the reference implementation provided by
the combination of the linux kernel dm-crypt module and cryptsetup
userspace tools.
There is a matrix of tests to be performed with different sets
of encryption settings. For each matrix entry, two tests will
be performed. One will create a LUKS image with the cryptsetup
tool and then do I/O with both cryptsetup & qemu-io. The other
will create the image with qemu-img and then again do I/O with
both cryptsetup and qemu-io.
The new I/O test 149 performs interoperability testing between
QEMU and the reference implementation. Such testing inherantly
requires elevated privileges, so to this this the user must have
configured passwordless sudo access. The test will automatically
skip if sudo is not available.
The test has to be run explicitly thus:
cd tests/qemu-iotests
./check -luks 149
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>