11.4. Permanently blocking and authorizing a USB device

Procedure

1. Configure SELinux to allow the usbguard daemon to write rules.

   1. Display the semanage Booleans relevant to usbguard.

      # semanage boolean -l | grep usbguard
      usbguard_daemon_write_conf     (off  ,  off)  Allow usbguard to daemon write conf
      usbguard_daemon_write_rules    (on   ,   on)  Allow usbguard to daemon write rules

   2. If the usbguard_daemon_write_rules Boolean is turned off, turn it on.

      # semanage boolean -m --on usbguard_daemon_write_rules

2. Determine the ID of the USB device by listing the devices recognized by USBGuard:

   # usbguard list-devices
   1: allow id 1d6b:0002 serial "0000:00:06.7" name "EHCI Host Controller" hash "JDOb0BiktYs2ct3mSQKopnOOV2h9MGYADwhT+oUtF2s=" parent-hash "4PHGcaDKWtPjKDwYpIRG722cB9SlGz9l9Iea93+Gt9c=" via-port "usb1" with-interface 09:00:00
   ...
   6: block id 1b1c:1ab1 serial "000024937962" name "Voyager" hash "CrXgiaWIf2bZAU+5WkzOE7y0rdSO82XMzubn7HDb95Q=" parent-hash "JDOb0BiktYs2ct3mSQKopnOOV2h9MGYADwhT+oUtF2s=" via-port "1-3" with-interface 08:06:50

3. Permanently authorize a device to interact with the system:

   # usbguard allow-device <ID> -p

4. Permanently deauthorize and remove a device:

   # usbguard reject-device <ID> -p

5. Permanently deauthorize and retain a device:

   # usbguard block-device <ID> -p

Verification

1. Check that the USBGuard rules include the changes you made.

   # usbguard list-rules