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25/10/2022 Decrypte/Crypte ne marche pas

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Lucàs
2022-10-25 15:14:01 +02:00
parent 3cc49f6515
commit 55e3499579
2 changed files with 94 additions and 36 deletions
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src/cryptography/Des.java
+85 -34
View File
@@ -7,11 +7,12 @@ package cryptography;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Random;
/**
* @author Lucàs VABRE
* @author Lucàs VABRE et les 2 autres
*/
public class Des {
@@ -19,7 +20,16 @@ public class Des {
private static final int TAILLE_SOUS_BLOC = 32;
private static final int NB_ROUND = 1;
private static final int[] TAB_DECALAGE = {1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1};
private static final int[] PERM_INITIALE = {58, 50, 42, 34, 26, 18, 10, 2, 60, 52, 44, 36, 28, 20, 12, 4, 62, 54, 46, 38, 30, 22, 14, 6, 64, 56, 48, 40, 32, 24, 16, 8, 57, 49, 41, 33, 25, 17, 9, 1, 59, 51, 43, 35, 27, 19, 11, 3, 61, 53, 45, 37, 29, 21, 13, 5, 63, 55, 47, 39, 31, 23, 15, 7};
private static final int[] PERM_INITIALE = {
58, 50, 42, 34, 26, 18, 10, 2,
60, 52, 44, 36, 28, 20, 12, 4,
62, 54, 46, 38, 30, 22, 14, 6,
64, 56, 48, 40, 32, 24, 16, 8,
57, 49, 41, 33, 25, 17, 9, 1,
59, 51, 43, 35, 27, 19, 11, 3,
61, 53, 45, 37, 29, 21, 13, 5,
63, 55, 47, 39, 31, 23, 15, 7
};
private static final int[][] S = {
{14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7},
{0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8},
@@ -86,9 +96,8 @@ public class Des {
public static void permutation(int[] tab_permutation, int[] bloc) {
int[] newTab = new int[bloc.length];
for (int i = 0; i < bloc.length; i++) {
newTab[i] = bloc[tab_permutation[i]];
newTab[i] = bloc[tab_permutation[i] % tab_permutation.length];
}
System.arraycopy(newTab, 0, bloc, 0, newTab.length);
@@ -97,29 +106,36 @@ public class Des {
public static void invPermuation(int[] tab_permutation, int[] bloc) {
int[] newTab = new int[bloc.length];
//// System.out.println(bloc.length);
for (int i = 0; i < bloc.length; i++) {
newTab[tab_permutation[i]] = bloc[i];
//// System.out.println(tab_permutation[i] % tab_permutation.length);
newTab[tab_permutation[i] % tab_permutation.length] = bloc[i];
}
System.arraycopy(newTab, 0, bloc, 0, newTab.length);
}
public static int[][] decoupage(int[] bloc, int nbBlocs) {
if (bloc.length % nbBlocs == 0) {
int z = bloc.length / nbBlocs;
int[][] newTab = new int[nbBlocs][z];
int y = 0;
for (int i = 0; i < bloc.length; i++) {
if (i % z == 0 && i > 0) {
y++;
}
newTab[y][i - y * z] = bloc[i];
}
return newTab;
int surplu = bloc.length % nbBlocs;
int z = (bloc.length) / nbBlocs;
if (surplu != 0) {
z = (bloc.length + (nbBlocs - surplu)) / nbBlocs;
}
return null;
int[][] newTab = new int[nbBlocs][z];
// Remplis le tableau de 0
for (int[] b : newTab) Arrays.fill(b, 0);
int y = 0;
for (int i = 0; i < bloc.length; i++) {
if (i % z == 0 && i > 0) {
y++;
}
newTab[y][i - y * z] = bloc[i];
}
return newTab;
}
public static int[] recollageBloc(int[][] blocs) {
@@ -148,6 +164,7 @@ public class Des {
public static int[] xor(int[] tab1, int[] tab2) {
int[] resultat = new int[tab1.length];
// System.out.println(resultat.length);
for (int i = 0; i < resultat.length; i++) {
resultat[i] = (tab1[i] + tab2[i]) % 2;
@@ -196,13 +213,17 @@ public class Des {
return resultat;
}
public int[] fonction_F(int[] unCle) {
public int[] fonction_F(int indice_cle, int[] Dn) {
//xor entre this.E et la cle trouvé à cette ronde
// this.genereCle(this.table_cles.size());
int[] Dn = xor(E, unCle);
int[] cle = this.table_cles.get(indice_cle);
int[] newDn = new int[48];
for (int i = 0; i < this.E.length; i++) {
newDn[i] = Dn[this.E[i] % Dn.length];
}
int[] Dn_prime = xor(cle, newDn);
//découpage en 8 blocs de 6 bits
int[][] decoupe = decoupage(Dn, 8);
int[][] decoupe = decoupage(Dn_prime, 8);
int[][] bloc = new int[8][4];
for (int i = 0; i < decoupe.length; i++) {
@@ -216,32 +237,62 @@ public class Des {
public int[] crypte(String message_clair) {
int[] msg_bit = stringToBits(message_clair);
int[][] decoupe = decoupage(msg_bit, (int) msg_bit.length / 64);
int[][] msg_crypte_bit = new int[(int)msg_bit.length / 64][64];
// // System.out.println(Arrays.toString(msg_bit));
// // System.out.println(msg_bit.length);
int taille = (int) Math.ceil(msg_bit.length / (float) TAILLE_BLOC) * 64;
for (int n = 0; n < 16; n++) {
int[] msgBit = new int[taille];
Arrays.fill(msgBit, 0);
// boucle du XOR
for (int y = 0; y < msg_bit.length; y++) {
msgBit[y] = (msgBit[y] + msg_bit[y]) % 2;
}
int[][] decoupe = decoupage(msgBit, (int) Math.ceil(msg_bit.length / (float) TAILLE_BLOC));
int[][] msg_crypte_bit = new int[msg_bit.length / TAILLE_BLOC][TAILLE_BLOC];
//Boucle de génération 16 des clés
for (int n = 0; n < (TAILLE_BLOC / 4); n++) {
this.genereCle(n);
}
for (int i = 0; i < decoupe.length - 1; i++) {
permutation(PERM_INITIALE, decoupe[i]);
int[][] decoupe2 = decoupage(decoupe[i], 2);
for (int n = 0; n < 16; n++) {
// this.genereCle(n);
decoupe2[1] = fonction_F(this.table_cles.get(n));
decoupe2[0] = fonction_F(this.table_cles.get(n));
int[] Gn1 = decoupe2[1];
int[] F = fonction_F(i, decoupe2[1]);
decoupe2[1] = xor(decoupe2[0], F);
decoupe2[0] = Gn1;
}
msg_crypte_bit[i] = recollageBloc(decoupe2);
invPermuation(PERM_INITIALE, msg_crypte_bit[i]);
}
return recollageBloc(msg_crypte_bit);
}
public static String decrypte(int[] messageCode) {
return null;
public String decrypte(int[] messageCode) {
int[][] decoupe = decoupage(messageCode, (int) (messageCode.length / TAILLE_BLOC));
for (int i = 0; i < decoupe.length; i++) {
permutation(PERM_INITIALE, decoupe[i]);
int[][] bloc32 = decoupage(decoupe[i], 2);
for (int n = 15; n >= 0; n--) {
int[] dn1 = bloc32[0];
bloc32[0] = xor(bloc32[1], fonction_F(i, dn1));
bloc32[1] = dn1;
}
decoupe[i] = recollageBloc(bloc32);
invPermuation(PERM_INITIALE, decoupe[i]);
}
int[] message_decrypte = recollageBloc(decoupe);
return bitsToString(message_decrypte);
}
}
src/cryptography/test/testDes.java
+9 -2
View File
@@ -90,8 +90,15 @@ public class testDes {
private static void testCrypte() {
Des des = new Des();
int [] msg = des.crypte("Bonjour");
System.out.println(Arrays.toString(msg));
System.out.println(Des.bitsToString(msg));
}
System.out.println(Arrays.toString(des.crypte("Hello World!")));
private static void testDecrypte() {
Des des = new Des();
int[] msg = des.crypte("Bonjour");
System.out.println(des.decrypte(msg));;
}
public static void main(String[] args) {
@@ -107,7 +114,7 @@ public class testDes {
// testGenereCle();
// testFonctionS();
// testFonctionF();
testCrypte();
testCrypte();
// testDecrypte();
}