The G2HEC (Genus 2 HyperElliptic Curve) is a free portable C++ library providing
divisor group operations in the Jacobian of a genus 2 (imaginary) hyperelliptic
curve over finite fields. It is useful for programmers and researchers in
mathematics and cryptography.
Get G2HEC on Github
https://github.com/syncom/libg2hec
G2HEC documentation: G2HEC Manual