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+# Users
+
+The user policy can group users by function within the car. For example, we can
+consider a driver and his passengers. Each user is assigned to a single group to
+simplify the management of space security.
+
+## Root Access
+
+The main applications, those that provide the principal functionality of the
+embedded device, should not execute with root identity or any capability.
+
+If the main application is allowed to execute at any capability, then the entire
+system is at the mercy of the said application's good behaviour. Problems arise
+when an application is compromised and able to execute commands which could
+consistently and persistently compromise the system by implanting rogue
+applications.
+
+It is suggested that the middleware and the UI should run in a context on a user
+with no capability and all persistent resources should be maintained without any
+capability.
+
+One way to ensure this is by implementing a server-client paradigm. Services
+provided by the system's drivers can be shared this way. The other advantage of
+this approach is that multiple applications can share the same resources at the
+same time.
+
+<!-- config -->
+
+Domain                | Object           | Recommendations
+--------------------- | ---------------- | -----------------------------------------------------
+Platform-Users-root-1 | Main application | Should not execute as root.
+Platform-Users-root-2 | UI               | Should run in a context on a user with no capability.
+
+<!-- endconfig -->
+
+Root access should not be allowed for the following utilities:
+
+<!-- config -->
+
+Domain                | `Utility` name | _State_
+--------------------- | -------------- | -------------
+Platform-Users-root-3 | `login`        | _Not allowed_
+Platform-Users-root-4 | `su`           | _Not allowed_
+Platform-Users-root-5 | `ssh`          | _Not allowed_
+Platform-Users-root-6 | `scp`          | _Not allowed_
+Platform-Users-root-7 | `sftp`         | _Not allowed_
+
+<!-- endconfig -->
+
+Root access should not be allowed for the console device. The development
+environment should allow users to login with pre-created user accounts.
+
+Switching to elevated privileges shall be allowed in the development environment
+via `sudo`.
+
+--------------------------------------------------------------------------------
+
+<!-- pagebreak -->
+
+## Capabilities
+
+<!-- todo -->
+
+Domain                        | Improvement
+----------------------------- | ------------------------
+Platform-Users-Capabilities-1 | Kernel or Platform-user?
+Platform-Users-Capabilities-2 | Add config note.
+
+<!-- endtodo -->
+
+The goal is to restrict functionality that will not be useful in **AGL**. They
+are integrated into the **LSM**. Each privileged transaction is associated with
+a capability. These capabilities are divided into three groups:
+
+- e: Effective: This means the capability is “activated”.
+- p: Permitted: This means the capability can be used/is allowed.
+- i: Inherited: The capability is kept by child/subprocesses upon execve() for example.