Dynamic link library integrity checking for handheld medical devices

摘要

A method of checking the integrity of a dynamic link library (DLL) file called by an application being executed on a handheld medical device is described. The method includes loading a DLL from a read only memory (ROM) to a random access memory (RAM) beginning at a fixed location in the RAM. The DLL includes a first routine for performing a safety critical function of the handheld medical device and a second routine for performing a cyclical redundancy check (CRC) once the DLL is loaded to the RAM. The method includes selectively executing the first routine from the RAM. The method includes selectively executing the second routine from the RAM including: calculating a check value based on the DLL; comparing the check value with a predetermined check value; and indicating that an error is present when the check value is different than the predetermined check value.

主权项

1. A method of checking the integrity of a dynamic link library (DLL) file called by an application being executed on a handheld medical device, the method comprising:
loading a DLL from nonvolatile memory to volatile memory beginning at a fixed location in the volatile memory, the DLL including a first routine for performing a safety critical function of the handheld medical device and including a second routine for performing a cyclical redundancy check (CRC) for the DLL once the DLL is loaded to the volatile memory; selectively executing the first routine from the volatile memory to perform the safety critical function; selectively executing the second routine from the volatile memory to perform the CRC including:
calculating a check value based on the DLL loaded to the volatile memory;comparing the check value with a predetermined check value set for the CRC; andgenerating an output indicating that an error is present when the check value is different than the predetermined check value.