Hashes won't match - mysql

Question

I took a few code snippets from that repo https://github.com/DanialK/PassportJS-Authentication , and adapted it so instead of using MongoDB I'm using MySQL. This is my code to check the password:
User.checkPassword = function(username, password, done) {
pool.getConnection(function(err,connection){
connection.query("SELECT * FROM " + userTable + " WHERE username=? LIMIT 1;",[username], function(err, user){
// if(err) throw err;
if(err) return done(err);
if(!user[0]){
console.log("Incorrect User")
return done(null, false, { message : 'Incorrect Username.' });
}
user = user[0];
hash(password, user.salt, function(err, hash){
hash = hash.toString("hex");
if(err) return done(err);
if(hash == user.hash){
console.log("SUCCESS!");
return done(null, user);
}
done(null, false, {
message : 'Incorrect password'
});
});
});
});
};
The MySQL field to store the hash is varchar(128), and before adding the hash to the table I use toString('hex') in the buffer to store it. The hash is made with https://github.com/visionmedia/node-pwd . My code look a lot like the tutorial's code but for MySQL. But when I try to compare the passwords, the hashes aren't equal. Why's that?
Here's the code that I use to register an user:
User.cadastrar = function(username,password,done){
var User = this;
hash(password, function(err, salt, hash){
hash = hash.toString('hex');
if(err) throw err;
// if (err) return done(err);
pool.getConnection(function(err,connection){
connection.query("INSERT INTO " + userTable + " (username,salt,hash) VALUES (?,?,?);", [username,salt,hash], function(err, user){
if(err) throw err;
// if (err) return done(err);
connection.query("SELECT * FROM " + userTable + " WHERE username=? LIMIT 1;",[username], function(err,user){
done(null, user[0]);
});
});
connection.release();
});
});
}