floodberry/ed25519-donna under Botan

main.cpp

#include "ed25519.h"
  
ed25519_secret_key sk;
Botan::AutoSeeded_RNG rng;
rng.randomize(sk, sizeof(ed25519_secret_key));

ed25519_public_key pk;
ed25519_publickey(sk, pk);

std::string msg("hello world");
const uint8_t* msgData = reinterpret_cast<const uint8_t*>(msg.c_str());

ed25519_signature sig;
ed25519_sign(msgData, msg.size(), sk, pk, sig);

int check = ed25519_sign_open(msgData, msg.size(), pk, sig);
if (check == 0)
  std::cout << "Signature is valid." << std::endl;
else if (check == 1)
  std::cout << "Signature failed." << std::endl;
else if (check == -1)
  std::cerr << "Ed25519 failure!" << std::endl;