Add python implementation of the legacy ogWindowsRegisterPartition
function.
This function configures the system partition to be considered the
new C drive after a Windows image restore.
The drive letter configuration is stored in the SYSTEM hive of
the windows registry. The node MountedDevices contains all the
configuration as key-value pairs.
The C drive key \DosDevices\C: contains a different value based on
the partitioning type.
GPT
the value is DMIO:ID: followed by the 16 byte GUID of the
partition.
Example: DMIO:ID:\xc9\xfc\x1c\x86\x13\x11O\t\xa2\x9c{/\xf1\xdf\xe4)
MBR
The value is a little endian byte sequence with 2 parts.
The first 4 bytes correspond to the disk id. The second part is
the byte offset start of the partition in that disk.
Example: \xe1\\\x9cP\x00\x00\x10j\x18\x00\x00\x00
If we format the MBR value in a more readable way we get
e1 5c 9c 50 00 00 10 6a 18 00 00 00
In this case the disk ID is 509c5ce1.
The partition offset is 186a100000.
This patch adds the following helper functions to:
- get_disk_id_bytes(): to obtain the disk identifier.
- get_part_id_bytes(): to obtain a partition identifier as UUID
for MBR or DMIO:ID format for GPT.
- get_sector_size(): to query the sector size of a specific disk.
Read /sys/class/block/{device_name}/queue/hw_sector_size to obtain the value.
This is MBR specific.
- get_partition_start_offset(): to query the start sector of a specific
partition and disk. Use sfdisk with the -J argument to get fdisk data in
json format. This is MBR specific.
Implement configure_fstab() as a replacement of ogConfigureFstab.
Create src/utils/fstab.py to implement the main fstab
configuration functions. Define two fstab helper classes,
FstabBuilder and FstabEntry.
FstabEntry
Represents each line in the fstab file.
Has the values: device, mountpoint, fstype, options, dump_code
and pass_code.
FstabBuilder
Contains a list of FstabEntry. Handles loading of a
preexisting fstab file and the serialization of multiple
FstabEntry into a file.
The fstab configuration has 3 main steps:
Root partition:
- Update the device field with the device where
the new system is installed.
Swap partition:
- Preserve all the swapfile entries in every case.
- If the filesystem has a swap partition: update the device field
in the first fstab swap entry and remove the rest swap entries
pointing to a swap partition. Only one swap partition is supported.
Create a new fstab entry if no preexisting swap entry exists.
- If the system has no swap partition remove every swap partition
entry.
EFI partition:
- Update the device field of the EFI fstab entry if it exists.
Create a new fstab entry if no preexisting EFI entry exists.
Add get_filesystem_id to disk.py to obtain the UUID.
Define every device field as a UUID. That method is more robust
than a plain device path as it works after disks being added or
removed.
Add function to redefine the hostname of a Windows install.
Windows hostnames can't be larger than 15 characters due to
legacy heritage.
Hostname modification is done by modifying 3 registry values in
the ControlSetXXX entry of the SYSTEM hive. ControlSet001 is
generally the entry to be edited but one must query the value
of the 'Current' key in the 'Select' entry of the SYSTEM hive
to retrieve the active ControlSet.
The hostname has to be introduced in the following entries:
path = 'ControlSetXX/Control/ComputerName/ComputerName'
key = 'ComputerName'
path = 'ControlSetXXX/Services/Tcpip/Parameters'
key = 'HostName'
key = 'NV Hostname'
The value to store in those keys is of tipe SZ and has to be
encoded in UCS-2 Little Endian (utf-16-le).
Replace ConfigureOs script by native calls to:
- update BCD via hivex using bcd.py and winreg.py infrastructure.
- restore efi bootloader restore_windows_efi_bootloader().
Call legacy scripts for remaining postinstall procedures to
replace them incrementally.
Define variable CONFIGUREOS_LEGACY_ENABLED as False by default.
Run legacy configureOs when CONFIGUREOS_LEGACY_ENABLED = True.
This serves as a auxiliar method to keep the restoration functional
in case of problems with the new configure_os logic.
Alejandro Sirgo Rica
OpenGnSys Support Team