Managing a security policy for a device

A non-transitory computer-readable storage medium storing program instructions that when executed by a computing platform operating on a device cause the computing platform to perform operations comprising:

• establishing a secure channel between a secure execution environment (SEE) operating on the device and a security entity external to the device;
• configuring, by a security manager executing on the SEE, access to sensitive operations of an environment interactor coupled to the device based on a security policy provided from the security entity;
• and
• resetting, by the security manager, a secure watchdog timer executing on the SEE in response to a reset authorization token provided from the secure entity;
• whereby, if the secure watchdog timer expires a given predetermined number of times since a last reset authorization token is received, the security manager executes a given prescriptive operation of a plurality of prescriptive operations dictated by the security policy and based on the given predetermined number of times the secure watchdog timer expires and if the secure watchdog timer expires another predetermined number of times since the last reset authorization token is received, the security manager executes another prescriptive operation of the plurality of prescriptive operations dictated by the security policy and based on the other predetermined number of times the secure watchdog timer expires, wherein the other predetermined number of times the secure watchdog timer expires is greater than the given predetermined number of times the secure watchdog timer expires.

A device comprising a computing platform, the computing platform comprising:

• a rich execution environment (REE) for controlling operations of an environment interactor coupled to the device;
• a secure execution environment (SEE) operating on the device that communicates with a security entity external to the device via a secure channel, the SEE comprising:
• a security manager that configures access to sensitive operations of the environment interactor coupled to the device based on a security policy provided from the security entity;
• and
• a secure watchdog timer that is reset in response to a reset authorization token provided from the secure entity;
• whereby, if the secure watchdog timer expires a given predetermined number of times since a last reset authorization token is received, the security manager executes a given prescriptive operation of a plurality of prescriptive operations dictated by the security policy and based on the given predetermined number of times the secure watchdog timer expires and if the secure watchdog timer expires another predetermined number of times since the last reset authorization token is received, the security manager executes another prescriptive operation of the plurality of prescriptive operations dictated by the security policy and based on the other predetermined number of times the secure watchdog timer expires, wherein the other predetermined number of times the secure watchdog timer expires is greater than the given predetermined number of times the secure watchdog timer expires.