Backup and Restore Feature in RPI - Design

Introduction

Backup and Restore is the feature developed in regard to WebUI.

The user can Backup the current user settings to the local PC and Restore the same to device when required.

Backup Settings:

• Allows the user to save the current settings
• Settings from database files are backed up in an encrypted format
• Generates a tar file of the encrypted database files
• Saves the tar file to Local PC.

Restore Settings:

• Allows the user to select the backup file with required settings
• Extracts the tar file and Decrypts the containing database files
• Loads backed up settings to device
• Device will be rebooted automatically to apply the settings.

Design Considerations

Backup and Restore functionalities are supported by a set of script files. Following are the mentioned script files:

   →   ConfPhp

   →  download_user_settings.php

   →   upload_user_settings1.php

   →   upload_user_settings2.php

   →   backup_user_settings.php

These script files which are already present in the RDK build, will execute when the Backup and Restore buttons are clicked.

Backup Settings

Scripts backup_user_settings.php, download_user_settings.php performs Encryption and download of the encrypted file.

It encrypts the database files which contains the Current User settings. A tar file is generated with encrypted files together and stored in temporary folder /tmp/. The tar file from temporary folder is downloaded to the Local PC of User.

Restore Settings

Scripts upload_user_settings1.php, upload_user_settings2.php perform the Restore and Status update functions.

The files which are uploaded in WebUI are extracted to get the encrypted files. These encrypted files are decrypted and the database files are saved to temporary folder /var/tmp/. The files are retrieved and replaced with the existing database files in RPi image.

Other Considerations (DAR)

<Alternative designs considered and why one was chosen>

Architecture

Limitations

The downloaded file, backup.tar is the default name given to the backup file. Once downloaded to Local PC, this file has to be replaced with new backup.tar file. If the old file is not deleted, it may cause misbehavior in Restore feature execution. The old file can be either deleted or renamed to avoid duplicate file creation. Please Refer User manual for further details.

During Restore, the file to be uploaded has to be named to backup.tar by default.

Future Enhancements

Backup feature:

•      Naming convention for the backup.tar file with versions/time of file creation can be automated. Example: backup_2711191230.tar for files generated on 27/11/19 12:30PM.
•      Encryption of the database files before generating the tar file.

•         Restore feature:
  •      During file upload, selection of files with any name, can be made possible. Example: Wifi_settings.tar
  •      Decryption of the database files after extracting the files from tar file.