This is the git repository for LibTomMath, a free open source portable number theoretic multiple-precision integer (MPI) library written entirely in C.

master:

develop:

master:

develop:

API/ABI changes: check here

We sometimes upload deb packages of the latest state from the develop branch to packagecloud.io.

Use those packages with caution and at your own discretion.

The develop branch contains the in-development version. Stable releases are tagged.

Documentation is built from the LaTeX file doc/bn.tex and available as PDF for each release. This PDF is also created as build artifact on each CI run.

There is also limited documentation in tommath.h.

Originally the library contained a document, tommath.pdf, which describes the goals of the project and many of the algorithms used at the time. This document has been removed since it can't be built anymore and nobody spent the time to fix and update it. The latest valid update to that document was done in version 0.39 of the library and it is contained within that tarball.

The project can be build by using make. Along with the usual make, make clean and make install, there are several other build targets, see the makefile for details. There are also makefiles for certain specific platforms.

Tests are located in demo/ and can be built in two flavors.

• make test creates a stand-alone test binary that executes several test routines.
• make mtest_opponent creates a test binary that is intended to be run against mtest. mtest can be built with make mtest and test execution is done like ./mtest/mtest | ./mtest_opponent. mtest is creating test vectors using an alternative MPI library and test is consuming these vectors to verify correct behavior of ltm

Building is straightforward for GNU Linux only, the section "Building LibTomMath" in the documentation in doc/bn.pdf has the details.

The project provides support for the CMake build system.

git clone https://github.com/libtom/libtommath.git
mkdir -p libtommath/build
cd libtommath/build
cmake ..
make -j$(nproc)

A shared library build can be done by setting -DBUILD_SHARED_LIBS=On when invoking the cmake command.