diff --git a/.gitignore b/.gitignore
index 295f9e6..03fdb9b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 serveur
 client
 attaque
+lib/test
\ No newline at end of file
diff --git a/lib/Makefile b/lib/Makefile
new file mode 100644
index 0000000..000d6f2
--- /dev/null
+++ b/lib/Makefile
@@ -0,0 +1,2 @@
+test: test_chiffrement.c rondoudouPatch.c rondoudouPatch.h
+	gcc -Wall -g test_chiffrement.c rondoudouPatch.c -o test
\ No newline at end of file
diff --git a/lib/rondoudouPatch.c b/lib/rondoudouPatch.c
new file mode 100644
index 0000000..d1ebb4d
--- /dev/null
+++ b/lib/rondoudouPatch.c
@@ -0,0 +1,107 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "rondoudouPatch.h"
+
+//WARNING SUR TOUT LES TYPES !!!
+
+struct t_pile_addrs {
+	int index;
+	void ** tab[TAB_SIZE];
+	struct t_pile_addrs * next;
+};
+
+uintptr_t rondoudou_patch_key;
+
+struct t_pile_addrs  * pile_addrs;
+
+void rondoudou_patch_init(void) {
+	pile_addrs = (struct t_pile_addrs *)malloc(sizeof(struct t_pile_addrs));
+	pile_addrs->index = -1;
+	pile_addrs->next = NULL;
+
+	rondoudou_patch_key = 12345;
+}
+
+int print_pile_aux(int profondeur, struct t_pile_addrs  * pile) {
+	if (pile != NULL) {
+		int prof_max = print_pile_aux(profondeur + 1, pile->next);
+		int i;
+		int max;
+		if (pile->index != TAB_SIZE) {
+			max = pile->index + 1;
+		} else { 
+			max = TAB_SIZE;
+		}
+		for (i = 0; i<max; i++) {
+			printf("%d -> %p\n", (prof_max - profondeur)*TAB_SIZE + i, pile->tab[i]);
+		}
+		return prof_max;
+	} else {
+		return profondeur - 1;
+	}
+}
+
+void print_pile(void) { 
+	print_pile_aux(0, pile_addrs);
+}	
+
+/*
+ *
+ *  ATTENTION !!!!! FONCTION ULTRA CHELOUE
+ *
+ */
+void ** find_address_in_stack(void * addr) {
+	void ** ret = 0;
+	int trouve = 0;
+	int i;
+	for (i=0; i<1000; i++) {
+		if ((*(&ret + i)) == addr) {
+			if (trouve) {
+				ret = (void **)(&ret + i);
+				break;
+			}
+			trouve = 1;
+		}
+	}
+
+	return ret;
+}
+
+void cipher(void * address) {
+	void ** addr = find_address_in_stack(address);
+	if (addr != 0) {
+		*addr = (void *)((uintptr_t)*addr ^ (uintptr_t)rondoudou_patch_key);
+		if ((pile_addrs->index) == (TAB_SIZE - 1)) {
+			struct t_pile_addrs  * aux = (struct t_pile_addrs *)malloc(sizeof(struct t_pile_addrs));
+			aux->index = 0;
+			aux->next = pile_addrs;
+			pile_addrs = aux;
+		} else {
+			pile_addrs->index++;
+		}
+		pile_addrs->tab[pile_addrs->index] = addr;
+		printf("APPEL A CIPHER\n");
+		print_pile();
+	}
+}
+
+void decipher(void) {
+	if (pile_addrs->index == -1) {
+		if (pile_addrs->next == NULL) {
+			printf("Ouille ouille ouille qu'est ce que j'ai mal aux nouilles ! \n");
+			exit(2);
+		} else {
+			struct t_pile_addrs  * aux = pile_addrs;
+			pile_addrs = pile_addrs->next;
+			free(aux);
+		}
+	}
+
+	*((pile_addrs->tab)[pile_addrs->index]) = (void *)((uintptr_t)(*((pile_addrs->tab)[pile_addrs->index])) ^ (uintptr_t)rondoudou_patch_key);
+	pile_addrs->index--;
+	printf("APPEL A DECIPHER\n");
+	print_pile();
+}
+
+void changekey(void);
diff --git a/lib/rondoudouPatch.h b/lib/rondoudouPatch.h
new file mode 100644
index 0000000..f9abbde
--- /dev/null
+++ b/lib/rondoudouPatch.h
@@ -0,0 +1,7 @@
+#define TAB_SIZE 3
+
+void cipher(void * addr);
+void decipher(void);
+void changekey(void);
+void rondoudou_patch_init(void);
+
diff --git a/lib/test_chiffrement.c b/lib/test_chiffrement.c
new file mode 100644
index 0000000..f6c49bf
--- /dev/null
+++ b/lib/test_chiffrement.c
@@ -0,0 +1,36 @@
+#include "rondoudouPatch.h"
+#include <stdio.h>
+
+void f() {
+	cipher(__builtin_return_address(0));
+	printf("Dans f()\n");
+	decipher();
+}
+
+void g() {
+	cipher(__builtin_return_address(0));
+	printf("Dans g()\n");
+	f();
+	decipher();
+}
+
+void h() {
+	cipher(__builtin_return_address(0));
+	printf("Dans h()\n");
+	g();
+	decipher();
+}
+
+void i() {
+	cipher(__builtin_return_address(0));
+	printf("Dans i()\n");
+	h();
+	decipher();
+}
+
+int main() {
+	rondoudou_patch_init();
+	cipher(__builtin_return_address(0));
+	i();
+	decipher();
+}