I'm fine with you making any of the changes you suggested.
So the only change I need to make is "specify what's happening in the storage driver"?
Can you elaborate what do you mean by that?
I can add something like:
For librbd engine, the encryption happens inside the librbd storage driver, so block read/write requests coming in from the hypervisor (qemu) are plaintext,
but encrypted by the storage driver before being persisted.
Is this the kind of thing you were thinking about?
-----"Peter Krempa" <pkrempa@xxxxxxxxxx> wrote: -----
>To: "Or Ozeri" <oro@xxxxxxxxxx>
>From: "Peter Krempa" <pkrempa@xxxxxxxxxx>
>Date: 10/21/2021 02:16PM
>Cc: libvir-list@xxxxxxxxxx, idryomov@xxxxxxxxx,
>to.my.trociny@xxxxxxxxx, dannyh@xxxxxxxxxx
>Subject: [EXTERNAL] Re: [PATCH v4 4/5] qemu: add librbd encryption
>engine
>
>On Thu, Oct 07, 2021 at 14:21:20 -0500, Or Ozeri wrote:
>> rbd encryption is new in qemu 6.1.0.
>> This commit adds a new encryption engine property which
>> allows the user to use this new encryption engine.
>>
>> Signed-off-by: Or Ozeri <oro@xxxxxxxxxx>
>> ---
>> docs/formatstorageencryption.html.in | 7 +-
>> docs/schemas/storagecommon.rng | 1 +
>> src/conf/storage_encryption_conf.c | 2 +-
>> src/conf/storage_encryption_conf.h | 1 +
>> src/qemu/qemu_block.c | 26 +++++++
>> src/qemu/qemu_domain.c | 34 +++++++++
>> ...sk-network-rbd-encryption.x86_64-6.0.0.err | 1 +
>> ...-network-rbd-encryption.x86_64-latest.args | 45 ++++++++++++
>> .../disk-network-rbd-encryption.xml | 63
>+++++++++++++++++
>> tests/qemuxml2argvtest.c | 2 +
>> ...k-network-rbd-encryption.x86_64-latest.xml | 70
>+++++++++++++++++++
>> tests/qemuxml2xmltest.c | 1 +
>> 12 files changed, 251 insertions(+), 2 deletions(-)
>> create mode 100644
>tests/qemuxml2argvdata/disk-network-rbd-encryption.x86_64-6.0.0.err
>> create mode 100644
>tests/qemuxml2argvdata/disk-network-rbd-encryption.x86_64-latest.args
>> create mode 100644
>tests/qemuxml2argvdata/disk-network-rbd-encryption.xml
>> create mode 100644
>tests/qemuxml2xmloutdata/disk-network-rbd-encryption.x86_64-latest.xm
>l
>>
>> diff --git a/docs/formatstorageencryption.html.in
>b/docs/formatstorageencryption.html.in
>> index 178fcd0d7c..02ee8f8ca3 100644
>> --- a/docs/formatstorageencryption.html.in
>> +++ b/docs/formatstorageencryption.html.in
>> @@ -27,7 +27,12 @@
>> The <code>encryption</code> tag supports an optional
><code>engine</code>
>> tag, which allows selecting which component actually handles
>> the encryption. Currently defined values of
><code>engine</code> are
>> - <code>qemu</code>.
>> + <code>qemu</code> and <code>librbd</code>.
>> + Both <code>qemu</code> and <code>librbd</code> require using
>the qemu driver.
>> + The <code>librbd</code> engine requires qemu version >=
>6.1.0,
>> + and is only applicable for RBD network disks.
>> + If the engine tag is not specified, the <code>qemu</code>
>engine will be
>> + used by default (assuming the qemu driver is used).
>
>Okay, this is slightly better but it doesn't specify what's happening
>in
>the storage driver.
>
>> </p>
>> <p>
>> The <code>encryption</code> tag can currently contain a
>sequence of
>
>[...]
>
>
>> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
>> index 354f65c6d5..13869dd79b 100644
>> --- a/src/qemu/qemu_domain.c
>> +++ b/src/qemu/qemu_domain.c
>> @@ -4814,6 +4814,40 @@
>qemuDomainValidateStorageSource(virStorageSource *src,
>> if (src->encryption) {
>> switch (src->encryption->engine) {
>> case VIR_STORAGE_ENCRYPTION_ENGINE_QEMU:
>> + switch ((virStorageEncryptionFormatType)
>src->encryption->format) {
>> + case VIR_STORAGE_ENCRYPTION_FORMAT_LUKS:
>> + case VIR_STORAGE_ENCRYPTION_FORMAT_QCOW:
>> + break;
>> +
>> + case VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT:
>> + case VIR_STORAGE_ENCRYPTION_FORMAT_LAST:
>> + default:
>> +
>virReportEnumRangeError(virStorageEncryptionFormatType,
>> +
>src->encryption->format);
>> + return -1;
>
>This here is okay, because both are basically impossible.
>
>> + }
>> +
>> + break;
>> + case VIR_STORAGE_ENCRYPTION_ENGINE_LIBRBD:
>> + if (!virQEMUCapsGet(qemuCaps,
>QEMU_CAPS_RBD_ENCRYPTION)) {
>> + virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
>"%s",
>> + _("librbd encryption is not
>supported by this QEMU binary"));
>> + return -1;
>> + }
>> +
>> + switch ((virStorageEncryptionFormatType)
>src->encryption->format) {
>> + case VIR_STORAGE_ENCRYPTION_FORMAT_LUKS:
>> + break;
>> +
>> + case VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT:
>> + case VIR_STORAGE_ENCRYPTION_FORMAT_QCOW:
>> + case VIR_STORAGE_ENCRYPTION_FORMAT_LAST:
>> + default:
>> +
>virReportEnumRangeError(virStorageEncryptionFormatType,
>> +
>src->encryption->format);
>
>This creates an error message which is not very informative.
>Specifically for VIR_STORAGE_ENCRYPTION_FORMAT_QCOW which is a
>legitimate configuration we need a proper error message.
>
>> + return -1;
>> + }
>> +
>> break;
>> case VIR_STORAGE_ENCRYPTION_ENGINE_DEFAULT:
>> case VIR_STORAGE_ENCRYPTION_ENGINE_LAST:
>
>[...]
>
>The test input files are okay. The output files will need some
>tweaking
>after recent changes. I think adding the error message is trivial
>enough
>so that I'll do it before pushing if you are okay with it.
>
>Reviewed-by: Peter Krempa <pkrempa@xxxxxxxxxx>
>
>
