[libvirt] [PATCH 2/2] storage: Check qemu-img encryption type capability

[John Ferlan]

On 04/17/2018 04:47 PM, Ján Tomko wrote:
> On Tue, Apr 17, 2018 at 03:23:33PM -0400, John Ferlan wrote:
>> https://bugzilla.redhat.com/show_bug.cgi?id=1526382
>>
>> As of QEMU 2.9, qemu-img has enforced using the "key-secret" for
>> creation of encrypted volumes. That is, LUKS encryption is now
>> required and the old (awful) qcow[2] encryption methodolgy is
>> no longer supported.
>>
>> In order to check for this, we scan the qemu-img -o help options
>> looking for "key-secret" and if set, we enforce during the create
>> volume processing that the about to be encrypted volume doesn't
>> attempt to use the old crufty encryption mechanism.
>>
>> Signed-off-by: John Ferlan <jferlan at redhat.com>
>> ---
>> src/storage/storage_util.c | 32 ++++++++++++++++++++++++++++++--
>> 1 file changed, 30 insertions(+), 2 deletions(-)
>>
>> diff --git a/src/storage/storage_util.c b/src/storage/storage_util.c
>> index 7df52239c2..d2e02a57ca 100644
>> --- a/src/storage/storage_util.c
>> +++ b/src/storage/storage_util.c
>> @@ -797,6 +797,7 @@ storagePloopResize(virStorageVolDefPtr vol,
>> enum {
>>     QEMU_IMG_BACKING_FORMAT_OPTIONS = 0,
>>     QEMU_IMG_BACKING_FORMAT_OPTIONS_COMPAT,
>> +    QEMU_IMG_BACKING_FORMAT_OPTIONS_KEY_SECRET,
>> };
>>
>> static char *
>> @@ -824,6 +825,14 @@ virStorageBackendQemuImgSupportsCompat(const char
>> *output)
>>     return strstr(output, "\ncompat ");
>> }
>>
>> +
>> +static bool
>> +virStorageBackendQemuImgRequiresKeySecret(const char *output)
>> +{
>> +    return strstr(output, "key-secret");
>> +}
>> +
>> +
> 
> NACK
> 
> adding more -help output scraping just for a nicer error message for a
> feature noone should be using in the first place is not worth it.
> 
> Jano


Fair enough - considering your other series...

As a consumer would you expect an error message for any create using
qcow[2] then?

Or should we just rip out the qcow[2] encryption stuff too?

IDC, either way.  It's the delta then between qemu 1.5 and 2.9 to
consider...

John