t3si_server.AES.java Source code

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Here is the source code for t3si_server.AES.java

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/*
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package t3si_server;

/*
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import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.util.Random;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.codec.binary.Base64;

/**
 *
 * @author Ervin
 */
public class AES {
    public static String generareCheieRandom(int lungime) {
        char[] caractere = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
        StringBuilder sb = new StringBuilder();
        Random random = new Random();
        for (int i = 0; i < lungime; i++) {
            char c = caractere[random.nextInt(caractere.length)];
            sb.append(c);
        }

        return sb.toString();
    }

    public static String generareK(int lungime) {
        char[] caractere = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
        StringBuilder sb = new StringBuilder();
        Random random = new Random();
        for (int i = 0; i < lungime - 2; i++) {
            char c = caractere[random.nextInt(caractere.length)];
            sb.append(c);
        }
        sb.append("==");
        return sb.toString();
    }

    public static String symmetricEncrypt(String text, String secretKey) {
        byte[] raw;
        String encryptedString;
        SecretKeySpec skeySpec;
        byte[] encryptText = text.getBytes();
        Cipher cipher;
        try {
            raw = Base64.decodeBase64(secretKey);
            skeySpec = new SecretKeySpec(raw, "AES");
            cipher = Cipher.getInstance("AES");
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
            encryptedString = Base64.encodeBase64String(cipher.doFinal(encryptText));
        } catch (Exception e) {
            e.printStackTrace();
            return "Error";
        }
        return encryptedString;
    }

    public static String symmetricDecrypt(String text, String secretKey) {
        Cipher cipher;
        String encryptedString;
        byte[] encryptText = null;
        byte[] raw;
        SecretKeySpec skeySpec;
        try {
            raw = Base64.decodeBase64(secretKey);
            skeySpec = new SecretKeySpec(raw, "AES");
            encryptText = Base64.decodeBase64(text);
            cipher = Cipher.getInstance("AES");
            cipher.init(Cipher.DECRYPT_MODE, skeySpec);
            encryptedString = new String(cipher.doFinal(encryptText));
        } catch (Exception e) {
            e.printStackTrace();
            return "Error";
        }
        return encryptedString;
    }

    public static void print() throws NoSuchAlgorithmException {
        int length = Cipher.getMaxAllowedKeyLength("AES");
        System.out.println(length);//prints the max key length
    }
}