ed25519cpp - Ed25519 C++17 implementation

This is a portable implementation of Ed25519 based on the SUPERCOP "ref10" implementation. The ed25519cpp wraps c-based implementing modern c++17 dialect. Additionally there is some extension which make easier the work with base58-encoded strings and pair of keys based on ed25519.

Home pages explains ed25519

1. https://ed25519.cr.yp.to/
2. https://en.wikipedia.org/wiki/EdDSA

Requirements

1. c++17
2. cmake
3. boost unitest installed includes (>=1.66, exclude 1.68!)

Build

git clone https://github.com/dnevera/ed25519cpp/
cd ./ed25519cpp; mkdir build; cd ./build
git clone https://github.com/dnevera/base64cpp
cd ./base64cpp; mkdir build; cd ./build

# mac os M1 universal bin
cmake -DCMAKE_OSX_ARCHITECTURES=arm64;x86_64 ..
cmake --build . && cmake --build . --target=install 

# or mac os Intel
cmake -DCMAKE_OSX_ARCHITECTURES=x86_64 ..
cmake --build . && cmake --build . --target=install 
ctest -C Debug -V

Build ios

# https://blog.tomtasche.at/2019/05/how-to-include-cmake-project-in-xcode.html

git clone https://github.com/dehancer/ios-cmake
cmake -G Xcode \
-DCMAKE_TOOLCHAIN_FILE=~/Develop/Dehancer/Dehancer-Plugins/ios-cmake/ios.toolchain.cmake\
-DENABLE_BITCODE=ON
-DPLATFORM=OS64COMBINED -DBUILD_TESTING=OFF \
-DCMAKE_INSTALL_PREFIX=~/Develop/local/ios/dehancer
cmake --build . --config Release && cmake --install . --config Release

Tested

1. Centos7 (gcc v7.0)
2. Ubuntu 18.04
3. OSX 10.13, XCode10

API

Examples

Random seed generator

#include "ed25519.hpp"


ed25519::Seed seed;
std::cout << "Seed base58 string: "<< seed.encode() << std::endl;

Create random keys pair

#include "ed25519.hpp"

if (auto pair = ed25519::keys::Pair::Random()){
    std::cout << "ed25519 random keys pair: "<< pair->get_public_key.encode() << "/" <<  pair->get_private_key().encode() << std::endl;
}

Create keys pair from private key

#include "ed25519.hpp"

auto error_handler = [](const std::error_code code){
    BOOST_TEST_MESSAGE("Test error: " + ed25519::StringFormat("code: %i, message: %s", code.value(), + code.message().c_str()));
};

if (auto pair = ed25519::keys::Pair::FromPrivateKey(secret_pair->get_private_key().encode(), error_handler)){
    std::cout << "ed25519 random keys pair: "<< pair->get_public_key.encode() << "/" <<  pair->get_private_key().encode() << std::endl;
}
else{
    // handling error
}

Create keys pair with secret phrase

#include "ed25519.hpp"


if (auto pair = ed25519::keys::Pair::WithSecret("some secret phrase", error_handler)){
    std::cout << "ed25519 random keys pair: "<< pair->get_public_key.encode() << "/" <<  pair->get_private_key().encode() << std::endl;
}
else{
    // handling error
}

Sign message

#include "ed25519.hpp"

// create pair
auto pair           = ed25519::keys::Pair::WithSecret("some secret phrase");

// some message 
std::string message = "some message or token string";

// sign message return uniq_ptr siganture
auto signature      = pair->sign(message);

if (signature->verify(message, pair->get_public_key())) {
   // handle verified
}

//
// It is not available to create empty signature:
// auto signature = ed25519::keys::Pair::Siganture()
// only copy operations or restore from base58-encoded string 
//
auto another_signature = ed25519::Signature::Decode(signature->encode());

//
// Handle errors when restoration
//

if (auto signature = ed25519::Signature::Decode("...some wrong encoded string ...", error_handler)){
    // handle verified
}
else {
    // handle error
}

Create digest hash from variant types

auto digest = Digest([pair](auto &calculator) {

        //
        // set big endian 
        // little endian is default
        //
        
        calculator.set_endian(Digest::Calculator::endian::big);
        
        std::cout << "Calculator endian: " << calculator.get_endian() << std::endl;

        calculator.append(true);

        calculator.append(1);

        calculator.append((int)(1.12f * 100));

        std::string title = "123";

        calculator.append(title);

        std::vector<unsigned char> v(title.begin(), title.end());

        calculator.append(v);

    });

//
// Encode to base58
//
auto base58 = digest.encode();

//
// Sign digest
//
auto siganture = pair->sign(digest);

if (siganture->verify(digest, pair->get_public_key())) {
    //
    // handle verified digest
    //
}

//
// Restore from base58-encded string
//
auto digest_restored = Digest::Decode(digest.encode(), error_handler);

if (digest_restored && siganture->verify(*digest_restored, pair->get_public_key())) {
    //
    // handle restored and verified
    //     
}

Windows

# Requrements: 
# Visual Studio, English Language Pack!
# https://vcpkg.info/
# GitBash

cd C:
git clone https://github.com/microsoft/vcpkg
cd /c/vcpkg/
./bootstrap-vcpkg.sh
/c/vcpkg/vcpkg integrate install
/c/vcpkg/vcpkg install gtest

# cmake integration
-DCMAKE_TOOLCHAIN_FILE=C:/vcpkg/scripts/buildsystems/vcpkg.cmake