Device and Method for Validation of Virtual Function Pointers

A method comprising:

• compiling a source code file, the source code file comprising one or more classes whereby each of the classes has a virtual table containing at least one virtual function pointer that is pointing to a virtual function;
• a virtual function invocation site associating with a virtual function in one of the classes;
• the compiling comprises:
• associating a security check function with the virtual function invocation site such that the associated security check function is executed prior to an invocation of the virtual function;
• generating a Class Hierarchy Hash Table (CHHT) whereby the generating comprises:
• hashing, for each class, an address of the virtual table with each virtual function pointer contained in the virtual table to produce a hash result for each of the virtual function pointers and associating each of the hash results with an indicator, and
• populating the CHHT with the hash results and their associated indicators;
• the security check function is configured to determine whether a virtual function pointer of a virtual function associated with the security check function is valid by looking up a indicator in the CHHT according to a hash result of the virtual function pointer of the virtual function and an address of a virtual table containing the virtual function pointer.

A device comprising:

• at least one processor;
• and
• a non-transitory media readable by the at least one processor, the non-transitory media storing instructions having one or more classes, whereby each of the classes has a virtual table containing at least one virtual function pointer that is pointing to a virtual function;
• the at least one processor executed the instructions to:
• detect a virtual function invocation site associating with a virtual function in one of the classes;
• execute a security check function to determine whether a virtual function pointer of the virtual function is valid by looking up a indicator in a Class Hierarchy Hash Table (CHHT) according to a hash result of the virtual function pointer of the virtual function and an address of a virtual table containing the virtual function pointer,
• the Class Hierarchy Hash Table (CHHT) comprising hash results and their associated indicators, the hash results being generated for each classe by:
• hashing an address of a virtual table with each virtual function pointer contained in the virtual table to produce a hash result for each of the virtual function pointers and associating each of the hash results with their indicator.

A method comprising:

• detecting, at an execution time, a virtual function invocation site associating with a virtual function in a compiled file;
• the compiled file has one or more classes whereby each of the classes has a virtual table containing at least one virtual function pointer that is pointing to a virtual function;
• executing a security check function to determine whether an virtual function pointer of the virtual function is valid by looking up an indicator in a Class Hierarchy Hash Table (CHHT) according to a hash result of the virtual function pointer of the virtual function and an address of a virtual table containing the virtual function pointer,
• the Class Hierarchy Hash Table (CHHT) comprising hash results and their associated indicators, the hash results being generated for each classe by:
• hashing an address of a virtual table with each virtual function pointer contained in the virtual table to produce a hash result for each of the virtual function pointers and associating each of the hash results with their indicator.