Apparatus and Method for Detecting Integrity Violation

An apparatus, comprising:

• a feedback shift register in a Fibonacci-configuration or in a Galois-configuration, the feedback shift register comprising:
• a plurality of registers connected in series, and
• a feedback function unit connected between an output of a number of the registers and an input of at least one of the registers;
• and
• an integrity violation detector adapted to:
• determine as to whether a sequence of values at an input or output of at least one of the registers, or a logic combination thereof, is a non-constant sequence or a constant sequence;
• and
• output an indication that the feedback shift register is in an integral state if the sequence of values is a non-constant sequence;
• or
• output an indication that the feedback shift register is subjected to an integrity violation if the sequence of values is a constant sequence;
• wherein the integrity violation detector comprises an online tester adapted to:
• count a length of runs of 0-Bits and 1-Bits in an inbound sequence of values;
• and
• output the indication that the feedback shift register is subjected to the integrity violation if the length of runs exceeds a predetermined value;
• wherein the feedback function unit is connected to the input of one of the plurality of registers via an XOR-gate, which is connected between the register and a preceding register, and an online tester is connected to the output of the preceding register;
• and/or
• a seed injection input is connected to the input of one of the plurality of registers via an XOR-gate, which is connected between the register and a preceding register, a logic circuit is connected in parallel between the output of the register and the output of the preceding register, and an online tester is connected to the output of the logic circuit;
• and/or
• the logic circuit comprises a series connection of a register and an XOR-gate, wherein the output of the XOR-gate is connected to the online tester;
• and/or
• the output of the preceding register is connected to the online tester in-line;
• and/or
• the online tester is connected to the input of a first register of the feedback shift register in-line.

An integrity violation detector adapted to detect an integrity violation exerted on an associated feedback shift register configured by a plurality of registers, the integrity violation detector being further adapted to:

• determine as to whether a sequence of values at an input or output of at least one of the registers, or a logic combination thereof, is a non-constant sequence or a constant sequence;
• and
• output an indication that the feedback shift register is in an integral state if the sequence of values is a non-constant sequence;
• or
• output an indication that the feedback shift register is subjected to an integrity violation if the sequence of values is a constant sequence.

A method for detecting an integrity violation exerted on a feedback shift register, the feedback shift register comprising:

• a plurality of registers connected in series, and
• a feedback function unit connected between an output of a number of the registers and an input of at least one of the registers;
• the method comprising:
• determining as to whether a sequence of values at an input or output of at least one of the plurality of registers comprised by the feedback shift register, or a logic combination thereof, is a non-constant sequence or a constant sequence;
• and
• putting out an indication that the feedback shift register is in an integral state if the sequence of values is a non-constant sequence;
• or
• putting out an indication that the feedback shift register is subjected to an integrity violation if the sequence of values is a constant sequence.

A non-transitory storage medium having stored thereon a computer program having a program code for performing, when running on a computer, a method for detecting an integrity violation exerted on a feedback shift register, the method comprising:

• determining as to whether a sequence of values at an input or output of at least one of a plurality of registers comprised by the feedback shift register, or a logic combination thereof, is a non-constant sequence or a constant sequence;
• and
• putting out an indication that the feedback shift register is in an integral state if the sequence of values is a non-constant sequence;
• or
• putting out an indication that the feedback shift register is subjected to an integrity violation if the sequence of values is a constant sequence.

An embedded system comprising a memory and a controller, wherein the controller is adapted to detect an integrity violation exerted on an feedback shift register implemented in software by a method comprising:

• determining as to whether a sequence of values at an input or output of at least one of the plurality of registers comprised by the feedback shift register, or a logic combination thereof, is a non-constant sequence or a constant sequence;
• and
• putting out an indication that the feedback shift register is in an integral state if the sequence of values is a non-constant sequence;
• or
• putting out an indication that the feedback shift register is subjected to an integrity violation if the sequence of values is a constant sequence.