Apple Inc.

Corey T Kallenberg

Xeno S Kovah

Joshua P De Cesare

Timothy R Paaske

Jeffrey R Wilcox

Hardik K Doshi

Kevin H Alderfer

Nikolaj Schlej

Andrew J Fish

Rafal Wojtczuk

Ezekiel T Runyon

A method and apparatus for performing a secure boot of a computer system is disclosed. A computer system according to the disclosure includes an auxiliary processor and a main processor. The boot process includes initially booting the auxiliary processor. The auxiliary processor includes a non-volatile memory storing boot code for the main processor. The auxiliary processor may perform a verification of the boot code. Subsequent to verifying the boot code, the main processor may be released from a reset state. Once the main processor is no longer in the reset state, the boot code may be provided thereto. Thereafter, the boot procedure may continue with the main processor executing the boot code.

Method and apparatus for secure system boot

Techniques are disclosed relating to securely booting a computer system. In some embodiments, a bootloader initiates a boot sequence to load an operating system of the computing device and detects firmware of a peripheral device to be executed during the boot process to initialize the peripheral device for use by the computing device. In response to the detecting, the bootloader instantiates a sandbox that isolates the firmware from the bootloader. In various embodiments, the firmware is loaded from an option read-only memory (OROM) included the peripheral device and executed during the boot sequence to initialize the peripheral device. In some embodiments, the bootloader assigns one or more memory address ranges to the firmware, and the sandbox restricts the firmware from accessing memory addresses that are not included in the assigned one or more address ranges.

Boot firmware sandboxing

A method and apparatus for protecting boot variables is disclosed. A computer system includes a main processor and an auxiliary processor. The auxiliary processor includes a non-volatile memory that stores variables associated with boot code that is also stored thereon. The main processor may send a request to the auxiliary processor to alter one of the variables stored in the non-volatile memory. Responsive to receiving the request, the auxiliary processor may execute a security policy to determine if the main processor meets the criteria for altering the variable. If the auxiliary processor determines that the main processor meets the criteria, it may grant permission to alter the variable.

Method and apparatus for boot variable protection

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Los Gatos, CA, United States of America

Corey T Kallenberg