A method for securely booting a target processor in a target system from a secure root of trust includes computing a message authentication code from boot code to be provided to the target processor, including an obfuscated algorithm for recreating the message authentication code in the target processor, serving the boot code to the target processor, executing the boot code to recreate the message authentication code in the target processor, serving the message authentication code back to the root of trust, comparing the returned message authentication code with the message authentication code generated in the root of trust, continuing execution of the boot code data if the returned message authentication code matches the message authentication code, and applying at least one penalty to the target system if the returned message authentication code does not match the message authentication code generated in the root of trust.