Computing device boot software authentication

An apparatus comprising:

• a main processor circuit;
• a main storage communicatively coupled to the main processor circuit and arranged to store an initial boot software component;
• a controller comprising a controller processor circuit communicatively coupled to the main storage, and a controller storage communicatively coupled to the controller processor circuit and arranged to store a boot routine comprising a sequence of instructions operative on the controller processor circuit to authenticate the initial boot software component;
• and
• the initial boot software component operative on the main processor circuit to:
• select a first set of boot software components of multiple sets of boot software components, each set of boot software components defines a pathway that branches from the initial boot software component and that rejoins at a latter boot software component, and the main storage stores at least one set of boot software components;
• and
• authenticate a first boot software component of the first set of boot software components to form a chain of authentication that extends from the boot routine and into a first pathway defined by the first set of boot software components.

A computer-implemented method comprising:

• executing a sequence of instructions of a boot routine on a first processor circuit to employ a first public key of the boot routine to authenticate an initial boot software component;
• executing a sequence of instructions of the initial boot software component on a second processor circuit to select a first set of boot software components of multiple sets of boot software components, each set of boot software components defining a pathway branching from the initial boot software component and rejoining at a latter boot software component;
• and
• executing a sequence of instructions of the initial boot software component on the second processor circuit to employ a second public key of the initial boot software component to authenticate a first boot software component of the first set of boot software components, forming a chain of authentication from the boot routine and into a first pathway defined by the first set of boot software components.

At least one machine-readable storage medium comprising instructions that when executed by a computing device, cause the computing device to:

• select a first set of boot software components of multiple sets of boot software components, each set of boot software components defining a pathway branching from an initial boot software component and rejoining at a latter boot software component;
• employ a first public key of the initial boot software component to authenticate a first boot software component of the first set of boot software components;
• and
• employ a second public key of the first boot software component to authenticate a second boot software component of the first set of boot software components, forming a chain of authentication from the initial boot software component through a first pathway defined by the first set of boot software components.