CODEWITHSUNDEEP
javasql-server
WhiteB1
WhiteB1

Reputation: 51

Storing a byte array in MS-SQL

I have problem with restoring byte array from ms sql database, can someone help me?

I have database with table called sec, that has two attributes 'ID_uzivatele' - varchar(20) and 'salt' - varbinary(50). I would like to store a byte[] salt in this table and then restore it back to byte[] receivedSalt, but if I compare both byte arrays, it doesn´t equal:

import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class test {
    public static void main(String[] args) {
        try {
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            Connection conn = DriverManager.getConnection("jdbc:odbc:JavaProject");

            byte[] salt = generateSalt();

            PreparedStatement insert = conn.prepareStatement("INSERT INTO sec VALUES ('id001', ?)");
            insert.setBytes(1, salt);
            insert.executeUpdate();
            insert.close();
            System.out.println("values are succesfully inserted to database");

            Statement select = conn.createStatement();
            ResultSet rs = select.executeQuery("SELECT salt FROM sec WHERE ID_uzivatele = 'id001'");
            rs = select.getResultSet();

            try {
                while (rs.next()) {
                    byte[] receivedSalt = rs.getBytes("salt");
                    if (salt.equals(receivedSalt)) System.out.println("match");
                    else System.out.println("no match");
                }
            }
            finally {
                rs.close();
                select.close();
            }

        } catch (ClassNotFoundException | SQLException | NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
    }

    public static byte[] generateSalt() throws NoSuchAlgorithmException {
        // VERY important to use SecureRandom instead of just Random
        SecureRandom random = SecureRandom.getInstance("SHA1PRNG");

        // Generate a 8 byte (64 bit) salt as recommended by RSA PKCS5
        byte[] salt = new byte[8];
        random.nextBytes(salt);

        return salt;
    }
}

Upvotes: 2

Views: 6321

Answers (1)

WhiteB1
WhiteB1

Reputation: 51

ok, I got it, I used wrong comparison method:

if (salt.equals(receivedSalt)) System.out.println("match");

so it works with this one:

if (Arrays.equals(salt, receivedSalt)) System.out.println("match");

Upvotes: 1

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