Implementing efficient 384-bit NIST elliptic curve over prime fields on an ARM946E.

摘要

This thesis presents a performance evaluation of a 384-bit NIST elliptic curve over prime fields on a 32-bit ARM946E microprocessor running at 100-MHz. While adhering to the constraints of an embedded system, the following items were investigated to decrease computation time: the importance of the underlying finite arithmetic, the use of hardware accelerators, the use of memory options, and the use of available processor features.; The elliptic curve implementation utilized existing finite arithmetic C code to interface to an AiMEC Montgomery Exponentiator Core. The exponentiator core supports modular addition, modular multiplication, and exponentiation. The finite arithmetic C code also contained functions to perform operations which are not performed by the exponentiator such as non-modular multiplication, non-modular addition, and modular subtraction.; Multiple enhancements were made to the finite field arithmetic. These provided a 22% time reduction in execution time of the 384-bit elliptic curve multiplication. Enhancements included writing assembly functions, adding checks prior to performing a modular reduction, utilizing the exponentiator core only when modulus reduction was necessary, using multiplication if more than two additions are required and placing the finite arithmetic into its own library and using ARM mode. Other optimizations investigated including: cache usage, compiler options (speed vs. size), and Thumb instruction set vs. ARM instruction set provided minimal reduction, 3.6%, in the execution time.