Brute-force attack algorithm

[BSODMASTER]

So basically I want to test all combinations of characters in fixed size string passing them into Hashing function and testing the result with the target hash. Is there any algorithm for that?

[MiiNiPaa]

Main idea:

bool next(std::string& x)
{
    size_t len = x.size();
    bool overflow = true;
    while(overflow) {
        overflow = false;
        if(--len == 0) 
            return false;
        (x[len] == 'z')?(overflow = true, x[len] = 'a'):x[len] += 1;
    }
    return true;
}

std::pair<bool, std::string> brute5()
{
    std::string brute('a', 5);
    do
        if (hash(brute) == desired_hash)
           return std::make_pair(true, brute);
    while(next(brute));
    return std::make_pair(false, std::string());
}