Function toHex

lib/cipher.cpp:55–60

}

std::string toHex(const std::string& s) {
    std::ostringstream oss;
    for (unsigned char c : s)
        oss << std::hex << std::setw(2) << std::setfill('0') << (int)c;
    return oss.str();
}

std::string fromHex(const std::string& hex) {
    if (hex.size() % 2 != 0) throw std::runtime_error("Invalid hex length");