Protection against attacks by generation of errors on jump instructions

A device for making a program secure against fault attacks wherein the device comprises:

• means for identifying in the program being made secure at least one jump instruction including a relative address chosen from a plurality of possible relative addresses for reaching a target address of the program being made secure in a memory area extending before and after the jump instruction and grouping the plurality of possible relative addresses;
• means for identifying, in the program being made secure, an instruction to be protected in the memory area;
• and
• means for inserting in the program be made secure at least one non-operative batch including at least one instruction for making at least the identified instruction secure, the insertion being carried out so that:
• the insertion is compatible with keeping the target address of the jump instruction inside the memory area after the insertion,
• the insertion is compatible with a normal execution of the program being made secure, after the insertion,
• wherein the non-operative batch is inserted into the program being made secure so that a circumvention instruction normally prevents execution of the at least one instruction of the non-operative batch, and an ejection instruction to an action program at the end of the non-operative batch prevents execution of instructions downstream of the non-operative batch, and
• wherein the non-operative batch is inserted after a first of said at least one jump instruction or the instruction to be protected.

A method of making a program secure against fault attacks, comprising:

• providing a program to be made secure, including at least one jump instruction including a relative address chosen from a plurality of possible relative addresses for reaching a target instruction of the program being made secure at a target address in a memory area extending before and after that jump instruction and grouping said plurality of possible relative addresses and an instruction to be protected within the memory area;
• a step of inserting, in the program to be made secure, at least one non-operative batch including at least one instruction so that:
• the insertion is compatible with keeping the target address of the jump instruction inside the memory area after the insertion, and
• the insertion is compatible with a normal execution of the program being made secure, after the insertion,
• wherein the non-operative batch is inserted into the program to be made secure so that a circumvention instruction normally prevents execution of the at least one instruction of the non-operative batch, and an ejection instruction to an action program at the end of the non-operative batch prevents execution of instructions downstream of the non-operative batch, and
• wherein the non-operative batch is inserted after a first of said at least one jump instruction or the instruction to be protected.

A method of making a program secure against fault attacks, comprising:

• providing a program to be made secure, including at least one jump instruction including a relative address chosen from a plurality of possible relative addresses for reaching a target instruction of the program being made secure at a target address in a memory area extending before and after that jump instruction and grouping said plurality of possible relative addresses and an instruction to be protected preceding the jump instruction within the memory area;
• a step of inserting in the program to be made secure at least one non-operative batch including at least one instruction between the instruction to be protected and the jump instruction so that:
• insertion is compatible with keeping the target address of the jump instruction inside the memory area after the insertion,
• the insertion is compatible with a normal execution of the program being made secure, after the insertion,
• wherein the non-operative batch is inserted into the program being made secure so that a circumvention instruction normally prevents execution of the at least one instruction of the non-operative batch, and an ejection instruction to an action program at the end of the non-operative batch prevents execution of instructions downstream of the non-operative batch, and
• wherein the non-operative batch is inserted after a first of said at least one jump instruction or the instruction to be protected.

A method of making a program secure against fault attacks, comprising:

• providing a program to be made secure, including at least one jump instruction including a relative address chosen from a plurality of possible relative addresses for reaching a target instruction of the program being made secure at a target address in a memory area extending before and after that jump instruction and grouping said plurality of possible relative addresses and an instruction to be protected following the jump instruction within the memory area;
• a step of inserting, in the program to be made secure, at least one non-operative batch including at least one instruction between the jump instruction and the instruction to be protected, the non-operative batch being configured so as to be executed only in case of disruption of the jump instruction and including at its end an ejection instruction preventing execution of instructions downstream of that non-operative batch, so that:
• the insertion is compatible with keeping the target address of the jump instruction inside the memory area after the insertion, and
• the insertion is compatible with a normal execution of the program being made secure after the insertion,
• wherein the non-operative batch is inserted into the program being made secure so that a circumvention instruction normally prevents execution of the at least one instruction of the non-operative batch, and an ejection instruction to an action program at the end of the non-operative batch prevents execution of instructions downstream of the non-operative batch, and
• wherein the non-operative batch is inserted after a first of said at least one jump instruction or the instruction to be protected.