v3: - Rebase on master - Add a test case for detached LUKS header - Adjust the design to honour preallocation of the payload device - Adjust the design to honour the payload offset from the header, even when detached - Support detached LUKS header creation using qemu-img - Support detached LUKS header querying - Do some code clean
Thanks for commenting on this series, please review. Best regared, Yong v2: - Simplify the design by reusing the LUKS driver to implement the generic Luks encryption, thank Daniel for the insightful advice. - rebase on master. This functionality was motivated by the following to-do list seen in crypto documents: https://wiki.qemu.org/Features/Block/Crypto The last chapter says we should "separate header volume": The LUKS format has ability to store the header in a separate volume from the payload. We should extend the LUKS driver in QEMU to support this use case. By enhancing the LUKS driver, it is possible to enable the detachable LUKS header and, as a result, achieve general encryption for any disk format that QEMU has supported. Take the qcow2 as an example, the usage of the generic LUKS encryption as follows: 1. add a protocol blockdev node of data disk $ virsh qemu-monitor-command vm '{"execute":"blockdev-add", > "arguments":{"node-name":"libvirt-1-storage", "driver":"file", > "filename":"/path/to/test_disk.qcow2"}}' 2. add a protocol blockdev node of LUKS header as above. $ virsh qemu-monitor-command vm '{"execute":"blockdev-add", > "arguments":{"node-name":"libvirt-2-storage", "driver":"file", > "filename": "/path/to/cipher.gluks" }}' 3. add the secret for decrypting the cipher stored in LUKS header above $ virsh qemu-monitor-command vm '{"execute":"object-add", > "arguments":{"qom-type":"secret", "id": > "libvirt-2-storage-secret0", "data":"abc123"}}' 4. add the qcow2-drived blockdev format node $ virsh qemu-monitor-command vm '{"execute":"blockdev-add", > "arguments":{"node-name":"libvirt-1-format", "driver":"qcow2", > "file":"libvirt-1-storage"}}' 5. add the luks-drived blockdev to link the qcow2 disk with LUKS header by specifying the field "header" $ virsh qemu-monitor-command vm '{"execute":"blockdev-add", > "arguments":{"node-name":"libvirt-2-format", "driver":"luks", > "file":"libvirt-1-format", "header":"libvirt-2-storage", > "key-secret":"libvirt-2-format-secret0"}}' 6. add the virtio-blk device finally $ virsh qemu-monitor-command vm '{"execute":"device_add", > "arguments": {"num-queues":"1", "driver":"virtio-blk-pci", > "drive": "libvirt-2-format", "id":"virtio-disk2"}}' The generic LUKS encryption method of starting a virtual machine (VM) is somewhat similar to hot-plug in that both maintaining the same json command while the starting VM changes the "blockdev-add/device_add" parameters to "blockdev/device". Hyman Huang (10): crypto: Introduce option and structure for detached LUKS header crypto: Support generic LUKS encryption qapi: Make parameter 'file' optional for BlockdevCreateOptionsLUKS crypto: Introduce creation option and structure for detached LUKS header crypto: Mark the payload_offset_sector invalid for detached LUKS header block: Support detached LUKS header creation using blockdev-create block: Support detached LUKS header creation using qemu-img crypto: Introduce 'detached-header' field in QCryptoBlockInfoLUKS tests: Add detached LUKS header case MAINTAINERS: Add section "Detached LUKS header" MAINTAINERS | 5 + block.c | 5 +- block/crypto.c | 146 ++++++++++-- block/crypto.h | 8 + crypto/block-luks.c | 49 +++- crypto/block.c | 1 + crypto/blockpriv.h | 3 + qapi/block-core.json | 14 +- qapi/crypto.json | 13 +- tests/qemu-iotests/210.out | 4 + tests/qemu-iotests/tests/luks-detached-header | 214 ++++++++++++++++++ .../tests/luks-detached-header.out | 5 + 12 files changed, 436 insertions(+), 31 deletions(-) create mode 100755 tests/qemu-iotests/tests/luks-detached-header create mode 100644 tests/qemu-iotests/tests/luks-detached-header.out -- 2.39.1
