The G2HEC (Genus 2 HyperElliptic Curve) library is a free portable C++ library providing divisor group operations in the Jacobian of genus 2 (imaginary) hyperelliptic curve. Such curves can be used for discrete-logarithm-based cryptosystems with advantages over elliptic curves (genus 1 curves). Divisor group operations are essential to using genus 2 curves for cryptography.
It is built on top of V. Shoup's NTL
library, "a high performance, portable C++
library providing data structures and algorithms for arbitrary length
integers; for vectors, matrices, and polynomials over the integers and
over finite fields; and for arbitrary precision floating point
arithmetic." G2HEC has been tested with NTL 5.5 on an x86_64 Ubuntu.
You may refer to build scripts
scripts/install-ntl-5.5.sh and
scripts/build.sh for sample commands building the
library.
It is recommended to build NTL using GMP (the GNU Multi-Precision package) for best performance. However, the G2HEC library can be built and used with and without the existence of GMP. The GMP library homepage: http://www.swox.com/gmp/.
This library does not assume users' familiarity with any non-trivial math background except basic concepts of finite fields and polynomials. No prior knowledge of genus 2 curve is needed to used the library.
The G2HEC library is released under the GNU Lesser General Public License Version 2.1. See the file COPYING for details.
On Ubuntu,
$ cd libg2hec/
# Install dependencies
$ sudo apt install autotools-dev autoconf texinfo build-essential bear
# Bootstrap
$ autoreconf -vi
# Build NTL and libg2hec
$ ./scripts/build.sh
# Install libg2hec
$ make install This installs NTL and libg2hec (including documentation) in a temporary
directory by default (useful for CI testing). You may override the
installation location using the INSTALL_DIR_PREFIX environment
variable when calling ./script/build.sh, e.g.,
INSTALL_DIR_PREFIX=/tmp/nssw ./script/build.sh