Booting device for a computer element and method for booting a computer element

A computer element comprising:

• a booting device for booting the computer element, the booting device comprising:
• a memory unit comprising an eFuse, the memory unit being configured to store a protection code outside of the eFuse;
• and
• a protection unit configured to check integrity of a software component of the computer element by reference to the protection code, the protection code being a program configured to be run by the protection unit, wherein the booting device is configured for executing the software component to boot the computer element,
• wherein the protection code is at least partially changeable from outside the booting device, on a one-time basis, via burn-in of a protection value of the protection code in the eFuse after the protection code is stored in the memory unit, outside of the eFuse, such that the protection code, after the burn-in in the eFuse, includes a first portion stored in the memory unit outside of the eFuse and a second portion stored in the eFuse,
• wherein the protection unit being configured to check the integrity of the software component of the computer element by reference to the protection code comprises the protection unit being configured, after the burn-in in the eFuse, to run the protection code including the first portion stored in the memory unit outside of the eFuse and the second portion stored in the eFuse,
• wherein the protection value comprises a comparative hash value, a cryptographic key, or the comparative hash value and the cryptographic key,
• wherein the booting device is configured to permit an alteration of the protection code from outside the booting device only in the event that:
• the booting device detects that the alteration of the protection code is executed via an interface of the protection unit that is provided by a manufacturer of the booting device for this purpose;
• the booting device detects that the alteration of the protection code is executed in accordance with a predefined standard, by reference to a predefined amendment file that is stipulated by the manufacturer of the booting device, or a combination thereof;
• the booting device detects that the alteration of the protection code is executed using a predefined configuration device of the manufacturer;
• the booting device only permits a one-time alteration of a respective region of the protection code, and the booting device detects that the alteration is a first alteration of the protection code in the respective region thereof, or
• any combination thereof, and
• wherein the protection unit being configured to check the integrity of the software component comprises the protection unit being configured to:
• hash a signature verification code with a hash code of the booting device, such that a first hash result is obtained;
• compare the first hash result with a signature verification code hash value of the memory unit;
• in the event that the comparison of the first hash result with the signature verification code hash value confirms that the first hash result and the signature verification code hash value are identical:
• acquire the software component, including a signature of the software component and a public key for the software component;
• hash the public key of the software component with the hash code of the booting device, such that a second hash result is obtained;
• compare the second hash result with a public key hash value of the memory unit;
• in the event that the comparison of the second hash result with the public key hash value confirms that the second hash result and the public key hash value are identical, check the signature of the software component by reference to the signature verification code;
• and
• in the event that the check of the signature of the software component confirms that the signature is correct, execute the software component.

A method for booting a computer element having a booting device the method comprising:

• saving, by a memory unit comprising an eFuse, a protection code outside of the eFuse;
• executing an integrity check on a software component of the computer element that is run upon the booting of the computer element, by reference to the protection code, the protection code being a program configured to be run by the protection unit;
• and
• at least partially altering the protection code from outside the booting device, on a one-time basis, the at least partially altering the protection code from outside the booting device comprising burning-in of a protection value of the protection code in the eFuse after the saving of the protection code in the memory unit, outside of the eFuse, such that the protection code, after the burn-in in the eFuse, includes a first portion stored in the memory unit outside of the eFuse and a second portion stored in the eFuse,
• wherein executing the integrity check on the software component of the computer element by reference to the protection code comprises, after the burning-in of the protection value in the eFuse, running the protection code including the first portion stored in the memory unit outside of the eFuse and the second portion stored in the eFuse,
• wherein the protection value comprises a comparative hash value, a cryptographic key, or the comparative hash value and the cryptographic key, wherein the booting device is configured to permit the at least partially altering the protection code from outside the booting device only in the event that:
• the booting device detects that the alteration of the protection code is executed via an interface of the protection unit that is provided by a manufacturer of the booting device for this purpose;
• the booting device detects that the alteration of the protection code is executed in accordance with a predefined standard, by reference to a predefined amendment file that is stipulated by the manufacturer of the booting device, or a combination thereof;
• the booting device detects that the alteration of the protection code is executed using a predefined configuration device of the manufacturer;
• the booting device only permits a one-time alteration of a respective region of the protection code, and the booting device detects that the alteration is a first alteration of the protection code in the respective region thereof, or
• any combination thereof, and
• wherein executing the integrity check on the software component of the computer element comprises:
• hashing a signature verification code with a hash code of the booting device, such that a first hash result is obtained;
• comparing the first hash result with a signature verification code hash value of the memory unit;
• in the event that the comparing of the first hash result with the signature verification code hash value confirms that the first hash result and the signature verification code hash value are identical:
• acquiring the software component, including a signature of the software component and a public key for the software component;
• hashing the public key of the software component with the hash code of the booting device, such that a second hash result is obtained;
• comparing the second hash result with a public key hash value of the memory unit;
• in the event that the comparing of the second hash result with the public key hash value confirms that the second hash result and the public key hash value are identical, checking the signature of the software component by reference to the signature verification code;
• and
• in the event that the checking of the signature of the software component confirms that the signature is correct, executing the software component.

In a non-transitory computer-readable storage medium that stores instructions executable by one or more processors for booting a computer element, the instructions comprising:

• saving, by a memory unit of a booting device, a protection code;
• executing, by a protection unit of the booting device, an integrity check on a software component of the computer element that is run upon the booting of the computer element, by reference to the protection code, the executing of the integrity check comprising:
• hashing a signature verification code with a hash code of the booting device, such that a first hash result is obtained;
• comparing the first hash result with a signature verification code hash value of the memory unit;
• and
• in the event that the comparing of the first hash result with the signature verification code hash value confirms that the first hash result and the signature verification code hash value are identical:
• acquiring the software component, including a signature of the software component and a public key for the software component;
• hashing the public key of the software component with the hash code of the booting device, such that a second hash result is obtained;
• comparing the second hash result with a public key hash value of the memory unit;
• in the event that the comparing of the second hash result with the public key hash value confirms that the second hash result and the public key hash value are identical, checking the signature of the software component by reference to the signature verification code;
• and
• in the event that the checking of the signature of the software component confirms that the signature is correct, executing the software component;
• and
• at least partially altering the protection code from outside the booting device.