Lecture Notes: Understanding File Permissions in Windows

Importance of File Permissions

• File permissions are crucial for computer security.
• Restrict access to files and directories to specific users.
• Analogies:
  • Social media privacy settings.
  • House key given to a relative for emergencies.

File Permissions in Windows

• Assigned using Access Control Lists (ACLs).
• Focus on Discretionary Access Control Lists (DACLs).
• System Access Control Lists (SACLs) are used for logging access events.

Discretionary Access Control Lists (DACLs)

• DACLs specify who can use a file and what actions they can perform.
• Each file/folder has an owner and one or more DACLs.

Viewing and Understanding Permissions

• Example using Windows Explorer:
  • Right-click on a directory (e.g., Desktop) and select properties.
  • Security tab shows permission details.
  • Users and groups listed with their respective permissions.

Types of Permissions

• Read: View file existence and content.
• Read and Execute: Includes Read; allows running executable files.
• List Folder Contents: Alias for Read and Execute on directories.
• Write: Modify a file or create subdirectories/files.
• Modify: Encompasses Read, Execute, and Write.
• Full Control: Complete access, including changing ownership and ACLs.

Using iCACLs Utility

• iCACLs is used to view and change ACLs.
• Command example: iCACLs Desktop.
• Outputs user accounts with access and their permissions.
• Permissions represented by letters (e.g., F for Full Control).

Understanding NTFS Permissions and Inheritance

• Permissions can be inherited:
  • OI: Object Inherit.
  • CI: Container Inherit.
• New files/directories inherit DACL from the parent folder.

These notes summarize the key points about file permissions in Windows, focusing on how permissions are assigned and managed, as well as the utilities used to view and modify these permissions.