dissect.hypervisor.backup.vma

Module Contents

Classes

VMA

Proxmox VMA.

Device

Extent

DeviceDataStream

Basic buffered stream that provides easy aligned reads.
class dissect.hypervisor.backup.vma.VMA(fh)

Proxmox VMA.

Parse and provide a readable object for devices in a Proxmox VMA backup file. VMA is designed to be streamed for extraction, so we need to do some funny stuff to create a readable object from it. Performance is not optimal, so it’s generally advised to extract a VMA instead. The vma-extract utility can be used for that.

property creation_time
blob_data(offset)
blob_string(offset)
config(name)
configs()
device(dev_id)
devices()
extents()
class dissect.hypervisor.backup.vma.Device(vma, dev_id, name, size)
__repr__()

Return repr(self).

open()
class dissect.hypervisor.backup.vma.Extent(fh, offset)
__repr__()

Return repr(self).

class dissect.hypervisor.backup.vma.DeviceDataStream(device)

Bases: dissect.util.stream.AlignedStream

Basic buffered stream that provides easy aligned reads.

Must be subclassed for various stream implementations. Subclasses can implement:

  • _read(offset, length)

  • _seek(pos, whence=io.SEEK_SET)

The offset and length for _read are guaranteed to be aligned. The only time that overriding _seek would make sense is if there’s no known size of your stream, but still want to provide SEEK_END functionality.

Most subclasses of AlignedStream take one or more file-like objects as source. Operations on these subclasses, like reading, will modify the source file-like object as a side effect.

Parameters:

  • size – The size of the stream. This is used in read and seek operations. None if unknown.

  • align – The alignment size. Read operations are aligned on this boundary. Also determines buffer size.