Method of securing execution of a program
View Patent ↗A method of securing execution of a main program that implements nested functions, the method comprising the steps of executing a security management program arranged to update a list of current functions, informing the security management program of the beginning of execution of each function of the main program and updating the list of current functions, informing the security management program of the end of execution of each function, and, after being informed of each end of execution of a function, verifying that the function is indeed the function that was begun the most recently.
1. A method of securing execution of a main program that implements nested functions, the method comprising the steps of:
executing a security management program arranged to update a list of current functions;
informing the security management program of a beginning of execution of each function of the main program and updating a list of current functions identifiers;
informing the security management program of an end of execution of each function;
after being informed of each end of execution of a function, verifying that the function is indeed the function that was begun the most recently; and
in the event of the verification failing, performing a protection action that is selected as a function of a security level associated with each function,
wherein the list of functions identifiers is a table comprising a sequence of fields for receiving respective function identifiers, the method comprising the steps of:
initializing the fields; and
on being informed of the beginning of the execution of a function, writing the identifier of the function in the first available field, and
wherein the identifier of each function contains a security level associated with the function and the security management program has access to a table associating protection actions that are to be performed according to security levels.
2. The method according to claim 1 , wherein the protection action consists of issuing a warning.
3. The method according to claim 1 , wherein the protection action consists of interrupting the main program.
4. The method according to claim 1 , wherein the security management program has access to a table of possible function calls from each function of the main program.
5. The method according to claim 1 , wherein, on being informed of the end of execution of a function called by a calling function, the method consists of storing the identifier of the function that is called in memory and causing the function calling the security manager to verify that the most-recently executed function is the called function.
6. The method according to claim 1 , wherein, at the beginning of execution of a function, the security management program activates at least one security countermeasure.