cryptographie

الموضوع في 'أرشيف المنتدى التعليمي' بواسطة zobairfr, بتاريخ ‏2 ديسمبر 2008.

  1. zobairfr

    zobairfr عضو فعال

    إنضم إلينا في:
    ‏21 فيفري 2008
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    59
      02-12-2008 19:32
    je cherche un algorithme de cryptage DES écrit en JAVA !!
    merci bien
     
  2. marouene

    marouene عضو نشيط

    إنضم إلينا في:
    ‏2 ديسمبر 2005
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      16-12-2008 19:27
    :besmellah1:

    mon ami vous pouvez utiliser les packages java.security et javax.crypto qui offrent la possibilité d'utiliser les algorithmes de cryptage et d'authentification les plus répandus telque DES(Data Encryption Standard) .

    voici un exple de code qui permet de crypter et decrypter un String en utilisant
    كود (text):
    DES :
        public class DesEncrypter {
            Cipher ecipher;
            Cipher dcipher;
       
            DesEncrypter(SecretKey key) {
                try {
                    ecipher = Cipher.getInstance("DES");
                    dcipher = Cipher.getInstance("DES");
                    ecipher.init(Cipher.ENCRYPT_MODE, key);
                    dcipher.init(Cipher.DECRYPT_MODE, key);
       
                ** catch (javax.crypto.NoSuchPaddingException e) {
                ** catch (java.security.NoSuchAlgorithmException e) {
                ** catch (java.security.InvalidKeyException e) {
                **
            **
       
            public String encrypt(String str) {
                try {
                    // Encode the string into bytes using utf-8
                    byte[] utf8 = str.getBytes("UTF8");
       
                    // Encrypt
                    byte[] enc = ecipher.doFinal(utf8);
       
                    // Encode bytes to base64 to get a string
                    return new sun.misc.BASE64Encoder().encode(enc);
                ** catch (javax.crypto.BadPaddingException e) {
                ** catch (IllegalBlockSizeException e) {
                ** catch (UnsupportedEncodingException e) {
                ** catch (java.io.IOException e) {
                **
                return null;
            **
       
            public String decrypt(String str) {
                try {
                    // Decode base64 to get bytes
                    byte[] dec = new sun.misc.BASE64Decoder().decodeBuffer(str);
       
                    // Decrypt
                    byte[] utf8 = dcipher.doFinal(dec);
       
                    // Decode using utf-8
                    return new String(utf8, "UTF8");
                ** catch (javax.crypto.BadPaddingException e) {
                ** catch (IllegalBlockSizeException e) {
                ** catch (UnsupportedEncodingException e) {
                ** catch (java.io.IOException e) {
                **
                return null;
            **
        **

    Here's an example that uses the class:

        try {
            // Generate a temporary key. In practice, you would save this key.
            // See also e464 Encrypting with DES Using a Pass Phrase.
            SecretKey key = KeyGenerator.getInstance("DES").generateKey();
       
            // Create encrypter/decrypter class
            DesEncrypter encrypter = new DesEncrypter(key);
       
            // Encrypt
            String encrypted = encrypter.encrypt("Don't tell anybody!");
       
            // Decrypt
            String decrypted = encrypter.decrypt(encrypted);
        ** catch (Exception e) {
        **
     


    voici l'algorithme en JAVA

    كود (text):
    import gnu.crypto.Registry;
    import gnu.crypto.Properties;
    import gnu.crypto.util.Util;

    import java.security.InvalidKeyException;
    import java.util.Arrays;
    import java.util.Collections;
    import java.util.Iterator;

    /**
     * <p>The Data Encryption Standard. DES is a 64-bit block cipher with a 56-bit
     * key, developed by IBM in the 1970's for the standardization process begun by
     * the National Bureau of Standards (now NIST).</p>
     *
     * <p>New applications should not use DES except for compatibility.</p>
     *
     * <p>This version is based upon the description and sample implementation in
     * [1].</p>
     *
     * <p>References:</p>
     * <ol>
     *    <li>Bruce Schneier, <i>Applied Cryptography: Protocols, Algorithms, and
     *    Source Code in C, Second Edition</i>. (1996 John Wiley and Sons) ISBN
     *    0-471-11709-9. Pages 265--301, 623--632.</li>
     * </ol>
     *
     * @version $Revision: 1.4 $
     */
    public class DES extends BaseCipher {

       // Constants and variables
       // -------------------------------------------------------------------------

       /** DES operates on 64 bit blocks. */
       public static final int BLOCK_SIZE = 8;

       /** DES uses 56 bits of a 64 bit parity-adjusted key. */
       public static final int KEY_SIZE = 8;

       // S-Boxes 1 through 8.
       private static final int[] SP1 = new int[] {
          0x01010400, 0x00000000, 0x00010000, 0x01010404,
          0x01010004, 0x00010404, 0x00000004, 0x00010000,
          0x00000400, 0x01010400, 0x01010404, 0x00000400,
          0x01000404, 0x01010004, 0x01000000, 0x00000004,
          0x00000404, 0x01000400, 0x01000400, 0x00010400,
          0x00010400, 0x01010000, 0x01010000, 0x01000404,
          0x00010004, 0x01000004, 0x01000004, 0x00010004,
          0x00000000, 0x00000404, 0x00010404, 0x01000000,
          0x00010000, 0x01010404, 0x00000004, 0x01010000,
          0x01010400, 0x01000000, 0x01000000, 0x00000400,
          0x01010004, 0x00010000, 0x00010400, 0x01000004,
          0x00000400, 0x00000004, 0x01000404, 0x00010404,
          0x01010404, 0x00010004, 0x01010000, 0x01000404,
          0x01000004, 0x00000404, 0x00010404, 0x01010400,
          0x00000404, 0x01000400, 0x01000400, 0x00000000,
          0x00010004, 0x00010400, 0x00000000, 0x01010004
       **;

       private static final int[] SP2 = new int[] {
          0x80108020, 0x80008000, 0x00008000, 0x00108020,
          0x00100000, 0x00000020, 0x80100020, 0x80008020,
          0x80000020, 0x80108020, 0x80108000, 0x80000000,
          0x80008000, 0x00100000, 0x00000020, 0x80100020,
          0x00108000, 0x00100020, 0x80008020, 0x00000000,
          0x80000000, 0x00008000, 0x00108020, 0x80100000,
          0x00100020, 0x80000020, 0x00000000, 0x00108000,
          0x00008020, 0x80108000, 0x80100000, 0x00008020,
          0x00000000, 0x00108020, 0x80100020, 0x00100000,
          0x80008020, 0x80100000, 0x80108000, 0x00008000,
          0x80100000, 0x80008000, 0x00000020, 0x80108020,
          0x00108020, 0x00000020, 0x00008000, 0x80000000,
          0x00008020, 0x80108000, 0x00100000, 0x80000020,
          0x00100020, 0x80008020, 0x80000020, 0x00100020,
          0x00108000, 0x00000000, 0x80008000, 0x00008020,
          0x80000000, 0x80100020, 0x80108020, 0x00108000
       **;

       private static final int[] SP3 = new int[] {
          0x00000208, 0x08020200, 0x00000000, 0x08020008,
          0x08000200, 0x00000000, 0x00020208, 0x08000200,
          0x00020008, 0x08000008, 0x08000008, 0x00020000,
          0x08020208, 0x00020008, 0x08020000, 0x00000208,
          0x08000000, 0x00000008, 0x08020200, 0x00000200,
          0x00020200, 0x08020000, 0x08020008, 0x00020208,
          0x08000208, 0x00020200, 0x00020000, 0x08000208,
          0x00000008, 0x08020208, 0x00000200, 0x08000000,
          0x08020200, 0x08000000, 0x00020008, 0x00000208,
          0x00020000, 0x08020200, 0x08000200, 0x00000000,
          0x00000200, 0x00020008, 0x08020208, 0x08000200,
          0x08000008, 0x00000200, 0x00000000, 0x08020008,
          0x08000208, 0x00020000, 0x08000000, 0x08020208,
          0x00000008, 0x00020208, 0x00020200, 0x08000008,
          0x08020000, 0x08000208, 0x00000208, 0x08020000,
          0x00020208, 0x00000008, 0x08020008, 0x00020200
       **;

       private static final int[] SP4 = new int[] {
          0x00802001, 0x00002081, 0x00002081, 0x00000080,
          0x00802080, 0x00800081, 0x00800001, 0x00002001,
          0x00000000, 0x00802000, 0x00802000, 0x00802081,
          0x00000081, 0x00000000, 0x00800080, 0x00800001,
          0x00000001, 0x00002000, 0x00800000, 0x00802001,
          0x00000080, 0x00800000, 0x00002001, 0x00002080,
          0x00800081, 0x00000001, 0x00002080, 0x00800080,
          0x00002000, 0x00802080, 0x00802081, 0x00000081,
          0x00800080, 0x00800001, 0x00802000, 0x00802081,
          0x00000081, 0x00000000, 0x00000000, 0x00802000,
          0x00002080, 0x00800080, 0x00800081, 0x00000001,
          0x00802001, 0x00002081, 0x00002081, 0x00000080,
          0x00802081, 0x00000081, 0x00000001, 0x00002000,
          0x00800001, 0x00002001, 0x00802080, 0x00800081,
          0x00002001, 0x00002080, 0x00800000, 0x00802001,
          0x00000080, 0x00800000, 0x00002000, 0x00802080
       **;

       private static final int[] SP5 = new int[] {
          0x00000100, 0x02080100, 0x02080000, 0x42000100,
          0x00080000, 0x00000100, 0x40000000, 0x02080000,
          0x40080100, 0x00080000, 0x02000100, 0x40080100,
          0x42000100, 0x42080000, 0x00080100, 0x40000000,
          0x02000000, 0x40080000, 0x40080000, 0x00000000,
          0x40000100, 0x42080100, 0x42080100, 0x02000100,
          0x42080000, 0x40000100, 0x00000000, 0x42000000,
          0x02080100, 0x02000000, 0x42000000, 0x00080100,
          0x00080000, 0x42000100, 0x00000100, 0x02000000,
          0x40000000, 0x02080000, 0x42000100, 0x40080100,
          0x02000100, 0x40000000, 0x42080000, 0x02080100,
          0x40080100, 0x00000100, 0x02000000, 0x42080000,
          0x42080100, 0x00080100, 0x42000000, 0x42080100,
          0x02080000, 0x00000000, 0x40080000, 0x42000000,
          0x00080100, 0x02000100, 0x40000100, 0x00080000,
          0x00000000, 0x40080000, 0x02080100, 0x40000100
       **;

       private static final int[] SP6 = new int[] {
          0x20000010, 0x20400000, 0x00004000, 0x20404010,
          0x20400000, 0x00000010, 0x20404010, 0x00400000,
          0x20004000, 0x00404010, 0x00400000, 0x20000010,
          0x00400010, 0x20004000, 0x20000000, 0x00004010,
          0x00000000, 0x00400010, 0x20004010, 0x00004000,
          0x00404000, 0x20004010, 0x00000010, 0x20400010,
          0x20400010, 0x00000000, 0x00404010, 0x20404000,
          0x00004010, 0x00404000, 0x20404000, 0x20000000,
          0x20004000, 0x00000010, 0x20400010, 0x00404000,
          0x20404010, 0x00400000, 0x00004010, 0x20000010,
          0x00400000, 0x20004000, 0x20000000, 0x00004010,
          0x20000010, 0x20404010, 0x00404000, 0x20400000,
          0x00404010, 0x20404000, 0x00000000, 0x20400010,
          0x00000010, 0x00004000, 0x20400000, 0x00404010,
          0x00004000, 0x00400010, 0x20004010, 0x00000000,
          0x20404000, 0x20000000, 0x00400010, 0x20004010
       **;

       private static final int[] SP7 = new int[] {
          0x00200000, 0x04200002, 0x04000802, 0x00000000,
          0x00000800, 0x04000802, 0x00200802, 0x04200800,
          0x04200802, 0x00200000, 0x00000000, 0x04000002,
          0x00000002, 0x04000000, 0x04200002, 0x00000802,
          0x04000800, 0x00200802, 0x00200002, 0x04000800,
          0x04000002, 0x04200000, 0x04200800, 0x00200002,
          0x04200000, 0x00000800, 0x00000802, 0x04200802,
          0x00200800, 0x00000002, 0x04000000, 0x00200800,
          0x04000000, 0x00200800, 0x00200000, 0x04000802,
          0x04000802, 0x04200002, 0x04200002, 0x00000002,
          0x00200002, 0x04000000, 0x04000800, 0x00200000,
          0x04200800, 0x00000802, 0x00200802, 0x04200800,
          0x00000802, 0x04000002, 0x04200802, 0x04200000,
          0x00200800, 0x00000000, 0x00000002, 0x04200802,
          0x00000000, 0x00200802, 0x04200000, 0x00000800,
          0x04000002, 0x04000800, 0x00000800, 0x00200002
       **;

       private static final int[] SP8 = new int[] {
          0x10001040, 0x00001000, 0x00040000, 0x10041040,
          0x10000000, 0x10001040, 0x00000040, 0x10000000,
          0x00040040, 0x10040000, 0x10041040, 0x00041000,
          0x10041000, 0x00041040, 0x00001000, 0x00000040,
          0x10040000, 0x10000040, 0x10001000, 0x00001040,
          0x00041000, 0x00040040, 0x10040040, 0x10041000,
          0x00001040, 0x00000000, 0x00000000, 0x10040040,
          0x10000040, 0x10001000, 0x00041040, 0x00040000,
          0x00041040, 0x00040000, 0x10041000, 0x00001000,
          0x00000040, 0x10040040, 0x00001000, 0x00041040,
          0x10001000, 0x00000040, 0x10000040, 0x10040000,
          0x10040040, 0x10000000, 0x00040000, 0x10001040,
          0x00000000, 0x10041040, 0x00040040, 0x10000040,
          0x10040000, 0x10001000, 0x10001040, 0x00000000,
          0x10041040, 0x00041000, 0x00041000, 0x00001040,
          0x00001040, 0x00040040, 0x10000000, 0x10041000
       **;

       /**
        * Constants that help in determining whether or not a byte array is parity
        * adjusted.
        */
       private static final byte[] PARITY = {
          8,1,0,8,0,8,8,0,0,8,8,0,8,0,2,8,0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,3,
          0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,
          0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,
          8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,
          0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,
          8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,
          8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,
          4,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,8,5,0,8,0,8,8,0,0,8,8,0,8,0,6,8
       **;

       // Key schedule constants.

       private static final byte[] ROTARS = {
          1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21, 23, 25, 27, 28
       **;

       private static final byte[] PC1 = {
          56, 48, 40, 32, 24, 16,  8,  0, 57, 49, 41, 33, 25, 17,
           9,  1, 58, 50, 42, 34, 26, 18, 10,  2, 59, 51, 43, 35,
          62, 54, 46, 38, 30, 22, 14,  6, 61, 53, 45, 37, 29, 21,
          13,  5, 60, 52, 44, 36, 28, 20, 12,  4, 27, 19, 11,  3
       **;

       private static final byte[] PC2 = {
          13, 16, 10, 23,  0,  4,  2, 27, 14,  5, 20,  9,
          22, 18, 11,  3, 25,  7, 15,  6, 26, 19, 12,  1,
          40, 51, 30, 36, 46, 54, 29, 39, 50, 44, 32, 47,
          43, 48, 38, 55, 33, 52, 45, 41, 49, 35, 28, 31
       **;

       /**
        * Weak keys (parity adjusted): If all the bits in each half are either 0
        * or 1, then the key used for any cycle of the algorithm is the same as
        * all other cycles.
        */
       public static final byte[][] WEAK_KEYS = {
          Util.toBytesFromString("0101010101010101"),
          Util.toBytesFromString("01010101FEFEFEFE"),
          Util.toBytesFromString("FEFEFEFE01010101"),
          Util.toBytesFromString("FEFEFEFEFEFEFEFE")
       **;

       /**
        * Semi-weak keys (parity adjusted):  Some pairs of keys encrypt plain text
        * to identical cipher text. In other words, one key in the pair can decrypt
        * messages that were encrypted with the other key. These keys are called
        * semi-weak keys. This occurs because instead of 16 different sub-keys being
        * generated, these semi-weak keys produce only two different sub-keys.
        */
       public static final byte[][] SEMIWEAK_KEYS = {
          Util.toBytesFromString("01FE01FE01FE01FE"), Util.toBytesFromString("FE01FE01FE01FE01"),
          Util.toBytesFromString("1FE01FE00EF10EF1"), Util.toBytesFromString("E01FE01FF10EF10E"),
          Util.toBytesFromString("01E001E001F101F1"), Util.toBytesFromString("E001E001F101F101"),
          Util.toBytesFromString("1FFE1FFE0EFE0EFE"), Util.toBytesFromString("FE1FFE1FFE0EFE0E"),
          Util.toBytesFromString("011F011F010E010E"), Util.toBytesFromString("1F011F010E010E01"),
          Util.toBytesFromString("E0FEE0FEF1FEF1FE"), Util.toBytesFromString("FEE0FEE0FEF1FEF1")
       **;

       /** Possible weak keys (parity adjusted) --produce 4 instead of 16 subkeys. */
       public static final byte[][] POSSIBLE_WEAK_KEYS = {
          Util.toBytesFromString("1F1F01010E0E0101"),
          Util.toBytesFromString("011F1F01010E0E01"),
          Util.toBytesFromString("1F01011F0E01010E"),
          Util.toBytesFromString("01011F1F01010E0E"),
          Util.toBytesFromString("E0E00101F1F10101"),
          Util.toBytesFromString("FEFE0101FEFE0101"),
          Util.toBytesFromString("FEE01F01FEF10E01"),
          Util.toBytesFromString("E0FE1F01F1FE0E01"),
          Util.toBytesFromString("FEE0011FFEF1010E"),
          Util.toBytesFromString("E0FE011FF1FE010E"),
          Util.toBytesFromString("E0E01F1FF1F10E0E"),
          Util.toBytesFromString("FEFE1F1FFEFE0E0E"),
          Util.toBytesFromString("1F1F01010E0E0101"),
          Util.toBytesFromString("011F1F01010E0E01"),
          Util.toBytesFromString("1F01011F0E01010E"),
          Util.toBytesFromString("01011F1F01010E0E"),
          Util.toBytesFromString("01E0E00101F1F101"),
          Util.toBytesFromString("1FFEE0010EFEF001"),
          Util.toBytesFromString("1FE0FE010EF1FE01"),
          Util.toBytesFromString("01FEFE0101FEFE01"),
          Util.toBytesFromString("1FE0E01F0EF1F10E"),
          Util.toBytesFromString("01FEE01F01FEF10E"),
          Util.toBytesFromString("01E0FE1F01F1FE0E"),
          Util.toBytesFromString("1FFEFE1F0EFEFE0E"),

          Util.toBytesFromString("E00101E0F10101F1"),
          Util.toBytesFromString("FE1F01E0FE0E0EF1"),
          Util.toBytesFromString("FE011FE0FE010EF1"),
          Util.toBytesFromString("E01F1FE0F10E0EF1"),
          Util.toBytesFromString("FE0101FEFE0101FE"),
          Util.toBytesFromString("E01F01FEF10E01FE"),
          Util.toBytesFromString("E0011FFEF1010EFE"),
          Util.toBytesFromString("FE1F1FFEFE0E0EFE"),
          Util.toBytesFromString("1FFE01E00EFE01F1"),
          Util.toBytesFromString("01FE1FE001FE0EF1"),
          Util.toBytesFromString("1FE001FE0EF101FE"),
          Util.toBytesFromString("01E01FFE01F10EFE"),
          Util.toBytesFromString("0101E0E00101F1F1"),
          Util.toBytesFromString("1F1FE0E00E0EF1F1"),
          Util.toBytesFromString("1F01FEE00E01FEF1"),
          Util.toBytesFromString("011FFEE0010EFEF1"),
          Util.toBytesFromString("1F01E0FE0E01F1FE"),
          Util.toBytesFromString("011FE0FE010EF1FE"),
          Util.toBytesFromString("0101FEFE0001FEFE"),
          Util.toBytesFromString("1F1FFEFE0E0EFEFE"),
          Util.toBytesFromString("FEFEE0E0FEFEF1F1"),
          Util.toBytesFromString("E0FEFEE0F1FEFEF1"),
          Util.toBytesFromString("FEE0E0FEFEF1F1FE"),
          Util.toBytesFromString("E0E0FEFEF1F1FEFE")
       **;

       // Constructor(s)
       // -------------------------------------------------------------------------

       /** Default 0-argument constructor. */
       public DES() {
          super(Registry.DES_CIPHER, BLOCK_SIZE, KEY_SIZE);
       **

       // Class methods
       // -------------------------------------------------------------------------

       /**
        * <p>Adjust the parity for a raw key array. This essentially means that each
        * byte in the array will have an odd number of '1' bits (the last bit in
        * each byte is unused.</p>
        *
        * @param kb The key array, to be parity-adjusted.
        * @param offset The starting index into the key bytes.
        */
       public static void adjustParity(byte[] kb, int offset) {
          for (int i = offset; i < KEY_SIZE; i++) {
             kb[i] ^= (PARITY[kb[i] & 0xff] == 8) ? 1 : 0;
          **
       **

       /**
        * <p>Test if a byte array, which must be at least 8 bytes long, is parity
        * adjusted.</p>
        *
        * @param kb The key bytes.
        * @param offset The starting index into the key bytes.
        * @return <code>true</code> if the first 8 bytes of <i>kb</i> have been
        * parity adjusted. <code>false</code> otherwise.
        */
       public static boolean isParityAdjusted(byte[] kb, int offset) {
          int w = 0x88888888;
          int n = PARITY[kb[offset+0] & 0xff]; n <<= 4;
          n |= PARITY[kb[offset+1] & 0xff]; n <<= 4;
          n |= PARITY[kb[offset+2] & 0xff]; n <<= 4;
          n |= PARITY[kb[offset+3] & 0xff]; n <<= 4;
          n |= PARITY[kb[offset+4] & 0xff]; n <<= 4;
          n |= PARITY[kb[offset+5] & 0xff]; n <<= 4;
          n |= PARITY[kb[offset+6] & 0xff]; n <<= 4;
          n |= PARITY[kb[offset+7] & 0xff];
          return (n & w) == 0;
       **

       /**
        * <p>Test if a key is a weak key.</p>
        *
        * @param kb The key to test.
        * @return <code>true</code> if the key is weak.
        */
       public static boolean isWeak(byte[] kb) {
    //      return Arrays.equals(kb, WEAK_KEYS[0]) || Arrays.equals(kb, WEAK_KEYS[1])
    //          || Arrays.equals(kb, WEAK_KEYS[2]) || Arrays.equals(kb, WEAK_KEYS[3])
    //          || Arrays.equals(kb, WEAK_KEYS[4]) || Arrays.equals(kb, WEAK_KEYS[5])
    //          || Arrays.equals(kb, WEAK_KEYS[6]) || Arrays.equals(kb, WEAK_KEYS[7]);
          for (int i = 0; i < WEAK_KEYS.length; i++) {
             if (Arrays.equals(WEAK_KEYS[i], kb)) {
                return true;
             **
          **
          return false;
       **

       /**
        * <p>Test if a key is a semi-weak key.</p>
        *
        * @param kb The key to test.
        * @return <code>true</code> if this key is semi-weak.
        */
       public static boolean isSemiWeak(byte[] kb) {
    //      return Arrays.equals(kb, SEMIWEAK_KEYS[0])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[1])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[2])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[3])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[4])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[5])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[6])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[7])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[8])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[9])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[10])
    //          || Arrays.equals(kb, SEMIWEAK_KEYS[11]);
          for (int i = 0; i < SEMIWEAK_KEYS.length; i++) {
             if (Arrays.equals(SEMIWEAK_KEYS[i], kb)) {
                return true;
             **
          **
          return false;
       **

       /**
        * <p>Test if the designated byte array represents a possibly weak key.</p>
        *
        * @param kb the byte array to test.
        * @return <code>true</code> if <code>kb</code>represents a possibly weak key.
        * Returns <code>false</code> otherwise.
        */
       public static boolean isPossibleWeak(byte[] kb) {
          for (int i = 0; i < POSSIBLE_WEAK_KEYS.length; i++) {
             if (Arrays.equals(POSSIBLE_WEAK_KEYS[i], kb)) {
                return true;
             **
          **
          return false;
       **

       /**
        * <p>The core DES function. This is used for both encryption and decryption,
        * the only difference being the key.</p>
        *
        * @param in The input bytes.
        * @param i The starting offset into the input bytes.
        * @param out The output bytes.
        * @param o The starting offset into the output bytes.
        * @param key The working key.
        */
       private static void desFunc(byte[] in, int i, byte[] out, int o, int[] key) {
          int right, left, work;

          // Load.
          left  = (in[i++] & 0xff) << 24 | (in[i++] & 0xff) << 16
                | (in[i++] & 0xff) <<  8 |  in[i++] & 0xff;
          right = (in[i++] & 0xff) << 24 | (in[i++] & 0xff) << 16
                | (in[i++] & 0xff) <<  8 |  in[i  ] & 0xff;

          // Initial permutation.
          work  = ((left >>>  4) ^ right) & 0x0F0F0F0F;
          left  ^= work << 4;
          right ^= work;

          work  = ((left >>> 16) ^ right) & 0x0000FFFF;
          left  ^= work << 16;
          right ^= work;

          work  = ((right >>>  2) ^ left) & 0x33333333;
          right ^= work << 2;
          left  ^= work;

          work  = ((right >>>  8) ^ left) & 0x00FF00FF;
          right ^= work << 8;
          left  ^= work;

          right = ((right << 1) | ((right >>> 31) & 1)) & 0xFFFFFFFF;
          work = (left ^ right) & 0xAAAAAAAA;
          left  ^= work;
          right ^= work;
          left = ((left << 1) | ((left >>> 31) & 1)) & 0xFFFFFFFF;

          int k = 0, t;
          for (int round = 0; round < 8; round++) {
             work = right >>> 4 | right << 28;
             work ^= key[k++];
             t  = SP7[work & 0x3F]; work >>>= 8;
             t |= SP5[work & 0x3F]; work >>>= 8;
             t |= SP3[work & 0x3F]; work >>>= 8;
             t |= SP1[work & 0x3F];
             work = right ^ key[k++];
             t |= SP8[work & 0x3F]; work >>>= 8;
             t |= SP6[work & 0x3F]; work >>>= 8;
             t |= SP4[work & 0x3F]; work >>>= 8;
             t |= SP2[work & 0x3F];
             left ^= t;

             work = left >>> 4 | left << 28;
             work ^= key[k++];
             t  = SP7[work & 0x3F]; work >>>= 8;
             t |= SP5[work & 0x3F]; work >>>= 8;
             t |= SP3[work & 0x3F]; work >>>= 8;
             t |= SP1[work & 0x3F];
             work = left ^ key[k++];
             t |= SP8[work & 0x3F]; work >>>= 8;
             t |= SP6[work & 0x3F]; work >>>= 8;
             t |= SP4[work & 0x3F]; work >>>= 8;
             t |= SP2[work & 0x3F];
             right ^= t;
          **

          // The final permutation.
          right = (right << 31) | (right >>> 1);
          work = (left ^ right) & 0xAAAAAAAA;
          left  ^= work;
          right ^= work;
          left = (left << 31) | (left >>> 1);

          work = ((left >>> 8) ^ right) & 0x00FF00FF;
          left ^= work << 8;
          right ^= work;

          work = ((left >>> 2) ^ right) & 0x33333333;
          left  ^= work << 2;
          right ^= work;

          work = ((right >>> 16) ^ left) & 0x0000FFFF;
          right ^= work << 16;
          left  ^= work;

          work = ((right >>> 4) ^ left) & 0x0F0F0F0F;
          right ^= work << 4;
          left  ^= work;

          out[o++] = (byte)(right >>> 24);
          out[o++] = (byte)(right >>> 16);
          out[o++] = (byte)(right >>>  8);
          out[o++] = (byte) right;
          out[o++] = (byte)(left >>> 24);
          out[o++] = (byte)(left >>> 16);
          out[o++] = (byte)(left >>>  8);
          out[o  ] = (byte) left;
       **

       // Instance methods implementing BaseCipher
       // -------------------------------------------------------------------------

       public Object clone() {
          return new DES();
       **

       public Iterator blockSizes() {
          return Collections.singleton(new Integer(BLOCK_SIZE)).iterator();
       **

       public Iterator keySizes() {
          return Collections.singleton(new Integer(KEY_SIZE)).iterator();
       **

       public Object makeKey(byte[] kb, int bs) throws InvalidKeyException {
          if (kb == null || kb.length != KEY_SIZE)
             throw new InvalidKeyException("DES keys must be 8 bytes long");

          if (Properties.checkForWeakKeys()
                && (isWeak(kb) || isSemiWeak(kb) || isPossibleWeak(kb))) {
             throw new WeakKeyException();
          **

          int i, j, l, m, n;
          long pc1m = 0, pcr = 0;

          for (i = 0; i < 56; i++) {
             l = PC1[i];
             pc1m |= ((kb[l >>> 3] & (0x80 >>> (l & 7))) != 0)
                   ? (1L << (55 - i)) : 0;
          **

          Context ctx = new Context();

          // Encryption key first.
          for (i = 0; i < 16; i++) {
             pcr = 0;
             m = i << 1;
             n = m + 1;
             for (j = 0; j < 28; j++) {
                l = j + ROTARS[i];
                if (l < 28) pcr |= ((pc1m & 1L << (55 - l)) != 0)
                                 ? (1L << (55 - j)) : 0;
                else pcr |= ((pc1m & 1L << (55 - (l - 28))) != 0)
                          ? (1L << (55 - j)) : 0;
             **
             for (j = 28; j < 56; j++) {
                l = j + ROTARS[i];
                if (l < 56) pcr |= ((pc1m & 1L << (55 - l)) != 0)
                                 ? (1L << (55 - j)) : 0;
                else pcr |= ((pc1m & 1L << (55 - (l - 28))) != 0)
                          ? (1L << (55 - j)) : 0;
             **
             for (j = 0; j < 24; j++) {
                if ((pcr & 1L << (55 - PC2[j   ])) != 0) ctx.ek[m] |= 1 << (23 - j);
                if ((pcr & 1L << (55 - PC2[j+24])) != 0) ctx.ek[n] |= 1 << (23 - j);
             **
          **

          // The decryption key is the same, but in reversed order.
          for (i = 0; i < Context.EXPANDED_KEY_SIZE; i += 2) {
             ctx.dk[30 - i] = ctx.ek[i];
             ctx.dk[31 - i] = ctx.ek[i+1];
          **

          // "****" the keys.
          for (i = 0; i < 32; i += 2) {
             int x, y;

             x = ctx.ek[i  ];
             y = ctx.ek[i+1];

             ctx.ek[i  ] = ((x & 0x00FC0000)  <<  6) | ((x & 0x00000FC0)  << 10)
                         | ((y & 0x00FC0000) >>> 10) | ((y & 0x00000FC0) >>>  6);
             ctx.ek[i+1] = ((x & 0x0003F000)  << 12) | ((x & 0x0000003F)  << 16)
                         | ((y & 0x0003F000) >>>  4) |  (y & 0x0000003F);

             x = ctx.dk[i  ];
             y = ctx.dk[i+1];

             ctx.dk[i  ] = ((x & 0x00FC0000)  <<  6) | ((x & 0x00000FC0)  << 10)
                         | ((y & 0x00FC0000) >>> 10) | ((y & 0x00000FC0) >>>  6);
             ctx.dk[i+1] = ((x & 0x0003F000)  << 12) | ((x & 0x0000003F)  << 16)
                         | ((y & 0x0003F000) >>>  4) |  (y & 0x0000003F);
          **

          return ctx;
       **

       public void encrypt(byte[] in, int i, byte[] out, int o, Object K, int bs) {
          desFunc(in, i, out, o, ((Context) K).ek);
       **

       public void decrypt(byte[] in, int i, byte[] out, int o, Object K, int bs) {
          desFunc(in, i, out, o, ((Context) K).dk);
       **

       // Inner classe(s)
       // =========================================================================

       /**
        * Simple wrapper class around the session keys. Package-private so TripleDES
        * can see it.
        */
       final class Context {

          // Constants and variables
          // ----------------------------------------------------------------------

          private static final int EXPANDED_KEY_SIZE = 32;

          /** The encryption key. */
          int[] ek;

          /** The decryption key. */
          int[] dk;

          // Constructor(s)
          // ----------------------------------------------------------------------

          /** Default 0-arguments constructor. */
          Context() {
             ek = new int[EXPANDED_KEY_SIZE];
             dk = new int[EXPANDED_KEY_SIZE];
          **

          // Class methods
          // ----------------------------------------------------------------------

          // Instance methods
          // ----------------------------------------------------------------------

          byte[] getEncryptionKeyBytes() {
             return toByteArray(ek);
          **

          byte[] getDecryptionKeyBytes() {
             return toByteArray(dk);
          **

          byte[] toByteArray(int[] k) {
             byte[] result = new byte[4 * k.length];
             for (int i = 0, j = 0; i < k.length; i++) {
                result[j++] = (byte)(k[i] >>> 24);
                result[j++] = (byte)(k[i] >>> 16);
                result[j++] = (byte)(k[i] >>>  8);
                result[j++] = (byte) k[i];
             **
             return result;
          **
       **
    **
     
    pour plus de détails sur le source code il faut télécharger la biblio gnu.crypto et son code source
    :kiss:
     
    2 شخص معجب بهذا.
  3. hamzaelmekki

    hamzaelmekki عضو نشيط

    إنضم إلينا في:
    ‏28 فيفري 2008
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    292
      18-11-2009 05:15
    SVP je demande d'écrire un programme Java pour :

    Générer une clé privée RSA de 1024 bits.
    Générer un certi cat numérique de clé publique a partir d'une clé privée.
    merci mes amis.
     
  4. sa85

    sa85 عضو فعال

    إنضم إلينا في:
    ‏16 أوت 2009
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    809
      18-11-2009 22:55
    :besmellah2:
    Slt j'aimerais avoir ce même code mais en C/C++ Logiciel utilisé le Qt Creator
    Merci d'avance
    :tunis:
    [​IMG]
     
  5. hamzaelmekki

    hamzaelmekki عضو نشيط

    إنضم إلينا في:
    ‏28 فيفري 2008
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    235
    الإعجابات المتلقاة:
    292
      20-11-2009 16:19
    aucune réponse les amis?
     

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