diff --git a/tp3/Makefile b/tp3/Makefile
new file mode 100644
index 0000000..a98ae59
--- /dev/null
+++ b/tp3/Makefile
@@ -0,0 +1,13 @@
+all : test_df 
+
+./lib_tea/xtea.o : ./lib_tea/xtea.c
+	gcc -c ./lib_tea/xtea.c -o ./lib_tea/xtea.o
+
+df.o : df.c
+	gcc -c df.c
+
+test_df.o : test_df.c
+	gcc -c test_df.c
+
+test_df : test_df.o df.o ./lib_tea/xtea.o
+	gcc -o test_df df.o test_df.o ./lib_tea/xtea.o
diff --git a/tp3/df.c b/tp3/df.c
new file mode 100644
index 0000000..ab01a3e
--- /dev/null
+++ b/tp3/df.c
@@ -0,0 +1,31 @@
+#include "df.h"
+
+uint64 expm(uint64 m, uint64 e, uint64 mod)
+{
+    uint128 _r = 1;
+    uint128 _m = (uint128)m;
+    uint128 _mod = (uint128)mod;
+
+    while (e > 0) {
+        if (e % 2 == 1) {
+            _r = (_r * _m) % _mod;
+        }
+        _m = (_m * _m) % _mod;
+        e = e / 2;
+    }
+
+    return (uint64)_r;
+}
+
+uint64 generateur(uint64 p)
+{
+    uint64 q = (p - 1) / 2;
+    uint64 g = 2;
+    
+    while (1) {
+        if (expm(g, 2, p) != 1 && expm(g, q, p) != 1) {
+            return g;
+        }
+        g++;
+    }
+}
\ No newline at end of file
diff --git a/tp3/df.h b/tp3/df.h
new file mode 100644
index 0000000..0aba99a
--- /dev/null
+++ b/tp3/df.h
@@ -0,0 +1,15 @@
+#ifndef _DF_H
+#define _DF_H
+
+typedef unsigned __int128 uint128;
+typedef unsigned long long int uint64;
+
+uint64 expm(uint64 m, uint64 e, uint64 n);
+// calcule m^e modulo n
+
+uint64 generateur(uint64 p);
+// calcule un generateur de (Zp)*
+// en supposant que p est un nombre premier 
+// de Sophie Germain
+
+#endif
diff --git a/tp3/lib_tea/tea.c b/tp3/lib_tea/tea.c
new file mode 100644
index 0000000..f541848
--- /dev/null
+++ b/tp3/lib_tea/tea.c
@@ -0,0 +1,39 @@
+#include "tea.h"
+#include<string.h>
+#define TOUR 32
+
+void encrypt_tea (uint32_t * v, uint32_t* k) 
+{
+	uint32_t v0=v[0], v1=v[1], sum=0, i;           /* initialisation */
+	uint32_t delta=0x9e3779b9;                     /* constantes de clef */
+	uint32_t k0=k[0], k1=k[1], k2=k[2], k3=k[3];   /* mise en cache de la clef */
+	for (i=0; i < TOUR; i++) {                       /* boucle principale */
+		sum += delta;
+		v0 += ((v1<<4) + k0) ^ (v1 + sum) ^ ((v1>>5) + k1);
+		v1 += ((v0<<4) + k2) ^ (v0 + sum) ^ ((v0>>5) + k3);
+	}
+	v[0]=v0; v[1]=v1;
+}
+
+void decrypt_tea (uint32_t* v, uint32_t* k) 
+{
+	uint32_t v0=v[0], v1=v[1], sum=0xC6EF3720, i;  /* initialisation */
+	uint32_t delta=0x9e3779b9;                     /* constantes de clefs */
+	uint32_t k0=k[0], k1=k[1], k2=k[2], k3=k[3];   /* mise en cache de la clef */
+	for (i=0; i<TOUR; i++) {                         /* boucle principale */
+		v1 -= ((v0<<4) + k2) ^ (v0 + sum) ^ ((v0>>5) + k3);
+		v0 -= ((v1<<4) + k0) ^ (v1 + sum) ^ ((v1>>5) + k1);
+		sum -= delta;
+	}
+	v[0]=v0; v[1]=v1;
+}
+
+uint64_t hash_block_tea(char b[24])
+{
+	uint32_t v[2];
+	uint32_t k[4];
+	memcpy(v,b,2*sizeof(uint32_t));
+	memcpy(k,b+2*sizeof(uint32_t),4*sizeof(uint32_t));
+	encrypt_tea(v,k);
+	return ((uint64_t)v[0])<<32 | v[1];
+}
diff --git a/tp3/lib_tea/tea.h b/tp3/lib_tea/tea.h
new file mode 100644
index 0000000..ba07355
--- /dev/null
+++ b/tp3/lib_tea/tea.h
@@ -0,0 +1,8 @@
+#ifndef _TEA_H
+#define _TEA_H
+#include <stdint.h>
+void  encrypt_tea (uint32_t* v, uint32_t* k);
+void  decrypt_tea (uint32_t* v, uint32_t* k);
+uint64_t hash_block_tea(char b[24]);
+#endif
+
diff --git a/tp3/lib_tea/xtea.c b/tp3/lib_tea/xtea.c
new file mode 100644
index 0000000..769af64
--- /dev/null
+++ b/tp3/lib_tea/xtea.c
@@ -0,0 +1,34 @@
+#include "xtea.h"
+#include<string.h>
+#define TOUR 32
+
+void encrypt_xtea(uint32_t v[2], uint32_t const key[4]) {
+    unsigned int i;
+    uint32_t v0=v[0], v1=v[1], sum=0, delta=0x9E3779B9;
+    for (i=0; i < TOUR; i++) {
+        v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + key[sum & 3]);
+        sum += delta;
+        v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + key[(sum>>11) & 3]);
+    }
+    v[0]=v0; v[1]=v1;
+}
+void decrypt_xtea(uint32_t v[2], uint32_t const key[4]) {
+    unsigned int i;
+    uint32_t v0=v[0], v1=v[1], delta=0x9E3779B9, sum=delta*TOUR;
+    for (i=0; i < TOUR; i++) {
+        v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + key[(sum>>11) & 3]);
+        sum -= delta;
+        v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + key[sum & 3]);
+    }
+    v[0]=v0; v[1]=v1;
+}
+uint64_t hash_block_xtea(char b[24])
+{
+	uint32_t v[2];
+	uint32_t k[4];
+	memcpy(v,b,2*sizeof(uint32_t));
+	memcpy(k,b+2*sizeof(uint32_t),4*sizeof(uint32_t));
+	encrypt_xtea(v,k);
+	return ((uint64_t)v[0])<<32 | v[1];
+
+}
diff --git a/tp3/lib_tea/xtea.h b/tp3/lib_tea/xtea.h
new file mode 100644
index 0000000..8007875
--- /dev/null
+++ b/tp3/lib_tea/xtea.h
@@ -0,0 +1,8 @@
+#ifndef _TEA_H
+#define _TEA_H
+#include <stdint.h>
+void  encrypt_xtea (uint32_t* v, uint32_t const  k[]);
+void  decrypt_xtea (uint32_t* v, uint32_t const  k[]);
+uint64_t hash_block_xtea(char b[24]);
+#endif
+
diff --git a/tp3/reseau/Makefile b/tp3/reseau/Makefile
new file mode 100644
index 0000000..d0a3c3a
--- /dev/null
+++ b/tp3/reseau/Makefile
@@ -0,0 +1,32 @@
+all : clt srv clt_echo srv_echo
+
+clt.o:clt.c
+	gcc -c clt.c
+
+clt_echo.o:clt_echo.c
+	gcc -c clt_echo.c
+
+
+clt: clt.o
+	gcc -o clt clt.o
+
+clt_echo: clt_echo.o
+	gcc -o clt_echo clt_echo.o
+
+
+srv.o : srv.c
+	gcc -c srv.c
+
+srv_echo.o : srv_echo.c
+	gcc -c srv.c
+
+
+srv : srv.o
+	gcc -o srv srv.c
+
+srv_echo : srv_echo.o
+	gcc -o srv_echo srv_echo.c
+
+
+
+
diff --git a/tp3/reseau/clt.c b/tp3/reseau/clt.c
new file mode 100644
index 0000000..048dbce
--- /dev/null
+++ b/tp3/reseau/clt.c
@@ -0,0 +1,70 @@
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <netinet/tcp.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <resolv.h>
+#include <fcntl.h>
+#include <sys/time.h>
+#include <assert.h>
+#define MAXBUFF 4096 
+
+int main(int argc, char * argv[]) {
+	int sock,  z=0, fd;
+	char buff[MAXBUFF];
+	struct sockaddr_in server_addr;
+	int addrlen; 
+
+	if (argc != 4) {
+		printf("Usage: %s <IP-address> <port number> <file to send>\n",argv[0]);
+		exit(1);
+	}
+
+	sock = socket(AF_INET, SOCK_STREAM, 0);
+	assert(sock != -1);
+
+	bzero(&server_addr, sizeof(server_addr));
+	server_addr.sin_family = AF_INET;
+	server_addr.sin_port = htons(atoi(argv[2]));
+
+	assert( inet_aton(argv[1], (struct in_addr*)&server_addr.sin_addr.s_addr) != 0 );
+
+	addrlen = sizeof(server_addr);
+
+	fd = open(argv[3],O_RDONLY,0666); 
+	assert(fd != -1);
+
+	assert(connect(sock,(struct sockaddr *)&server_addr, addrlen) != -1);
+
+	while(1) {
+		
+		ssize_t mbytes, nbytes;
+
+		nbytes=read(fd,buff,MAXBUFF);
+
+		if (nbytes==-1) {
+			perror("read");
+			exit(1);
+		}
+		if (nbytes==0) {
+			break;
+		}
+
+		mbytes = write(sock,buff,nbytes);
+		if (mbytes == -1) {
+			perror("write");
+			exit(1);
+		}
+		z=z+mbytes;
+	}
+
+	printf("file %s sent (%d bytes)",argv[3],z);
+
+	close(sock);
+	exit(0);
+}
diff --git a/tp3/reseau/clt_echo.c b/tp3/reseau/clt_echo.c
new file mode 100644
index 0000000..e922963
--- /dev/null
+++ b/tp3/reseau/clt_echo.c
@@ -0,0 +1,73 @@
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <netinet/tcp.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <resolv.h>
+#include <fcntl.h>
+#include <sys/time.h>
+#include <assert.h>
+#define MAXBUFF 4096 
+
+int main(int argc, char * argv[]) {
+	int sock,  z=0, fd;
+	char buff[MAXBUFF];
+	struct sockaddr_in server_addr;
+	int addrlen; 
+
+	if (argc != 3) {
+		printf("Usage: %s <IP-address> <port number>\n",argv[0]);
+		exit(1);
+	}
+
+	sock = socket(AF_INET, SOCK_STREAM, 0);
+	assert(sock != -1);
+
+	bzero(&server_addr, sizeof(server_addr));
+	server_addr.sin_family = AF_INET;
+	server_addr.sin_port = htons(atoi(argv[2]));
+
+	assert( inet_aton(argv[1], (struct in_addr*)&server_addr.sin_addr.s_addr) != 0 );
+
+	addrlen = sizeof(server_addr);
+
+	//fd = open(argv[3],O_RDONLY,0666); 
+	//assert(fd != -1);
+
+	assert(connect(sock,(struct sockaddr *)&server_addr, addrlen) != -1);
+
+	while(1) {
+		
+		ssize_t mbytes, nbytes;
+
+		nbytes=read(0,buff,MAXBUFF);
+
+		if (nbytes==-1) {
+			perror("read");
+			exit(1);
+		}
+		if (nbytes==0) {
+			break;
+		}
+
+		mbytes = write(sock,buff,nbytes);
+		if (mbytes == -1) {
+			perror("write");
+			exit(1);
+		}
+nbytes=read(sock,buff,MAXBUFF);
+write(1,buff,nbytes);
+
+		z=z+mbytes;
+	}
+
+	printf("file %s sent (%d bytes)",argv[3],z);
+
+	close(sock);
+	exit(0);
+}
diff --git a/tp3/reseau/srv.c b/tp3/reseau/srv.c
new file mode 100644
index 0000000..37c0bab
--- /dev/null
+++ b/tp3/reseau/srv.c
@@ -0,0 +1,113 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <resolv.h>
+#include <arpa/inet.h>
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <assert.h>
+#define MAXBUFF 4096
+
+int handle_transferred_file(int sock,struct sockaddr_in * client_addr)
+{
+	char bufname[256];
+
+	char buff[MAXBUFF];
+	int fd;
+	ssize_t nbytes,z;
+
+	char addr[INET_ADDRSTRLEN];
+	snprintf(bufname,256,"%s.%d",inet_ntoa(client_addr->sin_addr),ntohs(client_addr->sin_port));
+	fd = open(bufname,O_WRONLY|O_CREAT|O_TRUNC,0666); 
+	if (fd == -1) {
+		perror("open");
+		exit(1);
+	}
+
+	while (1) {
+		//bzero(buff,MAXBUFF);
+		nbytes = read(sock,buff,MAXBUFF);
+		if (nbytes == -1) {
+			perror("read");
+			exit(1);
+		}
+		if (nbytes==0) break;
+
+		write(fd,buff,nbytes);
+		z=z+nbytes;
+	}
+
+	inet_ntop(AF_INET,&(client_addr->sin_addr.s_addr),addr,INET_ADDRSTRLEN);
+	printf("%d bytes recieved from %s\n", z, addr);
+	shutdown(sock,SHUT_RDWR);
+	close(sock);
+
+	exit(0);
+
+}
+
+int main(int argc, char * argv[]) 
+{
+	int 				/* file descriptor for the tranferred file */ 
+		listen_sock,    /* socket for listenning connection */
+		service_sock,   /* socket for a connected client */
+		nbytes, z=0;
+	int yes=1;
+
+	struct sockaddr_in server_addr, 
+					   client_addr;
+
+	int addr_len; 
+
+	struct sigaction sa;
+
+	if (argc != 2) {
+		printf("Usage: %s <port number>\n",argv[0]);
+		exit(1);
+	}
+
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_NOCLDWAIT;
+	sa.sa_handler = SIG_DFL;
+	assert (sigaction(SIGCHLD, &sa, NULL) != -1);
+
+
+
+	listen_sock = socket(AF_INET, SOCK_STREAM, 0);
+	assert( listen_sock > 0);
+
+	assert (setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) != -1);
+
+
+
+	bzero(&server_addr, sizeof(server_addr));
+	server_addr.sin_family = AF_INET;
+	server_addr.sin_port = htons(atoi(argv[1]));
+	server_addr.sin_addr.s_addr = INADDR_ANY;
+	addr_len = sizeof(server_addr);
+
+	assert(bind(listen_sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr)) != -1);
+
+	assert(listen(listen_sock,10) == 0);
+
+
+
+	while(1){
+
+		service_sock = accept(listen_sock,
+				(struct sockaddr *)&client_addr , 
+				&addr_len);
+
+		assert(service_sock >= 0);
+
+		pid_t p = fork();
+		if (p==0){
+			close(listen_sock);
+			handle_transferred_file(service_sock,&client_addr);
+		}
+	}
+}
diff --git a/tp3/reseau/srv_echo.c b/tp3/reseau/srv_echo.c
new file mode 100644
index 0000000..4085576
--- /dev/null
+++ b/tp3/reseau/srv_echo.c
@@ -0,0 +1,113 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <resolv.h>
+#include <arpa/inet.h>
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <assert.h>
+#define MAXBUFF 4096
+
+int handle_transferred_file(int sock,struct sockaddr_in * client_addr)
+{
+	char bufname[256];
+
+	char buff[MAXBUFF];
+	int fd;
+	ssize_t nbytes,z;
+
+	char addr[INET_ADDRSTRLEN];
+	snprintf(bufname,256,"%s.%d",inet_ntoa(client_addr->sin_addr),ntohs(client_addr->sin_port));
+	//fd = open(bufname,O_WRONLY|O_CREAT|O_TRUNC,0666); 
+	//if (fd == -1) {
+	//	perror("open");
+	//	exit(1);
+	//}
+
+	while (1) {
+		//bzero(buff,MAXBUFF);
+		nbytes = read(sock,buff,MAXBUFF);
+		if (nbytes == -1) {
+			perror("read");
+			exit(1);
+		}
+		if (nbytes==0) break;
+
+		write(sock,buff,nbytes);
+		z=z+nbytes;
+	}
+
+	inet_ntop(AF_INET,&(client_addr->sin_addr.s_addr),addr,INET_ADDRSTRLEN);
+	printf("%d bytes recieved from %s\n", z, addr);
+	shutdown(sock,SHUT_RDWR);
+	close(sock);
+
+	exit(0);
+
+}
+
+int main(int argc, char * argv[]) 
+{
+	int 				/* file descriptor for the tranferred file */ 
+		listen_sock,    /* socket for listenning connection */
+		service_sock,   /* socket for a connected client */
+		nbytes, z=0;
+	int yes=1;
+
+	struct sockaddr_in server_addr, 
+					   client_addr;
+
+	int addr_len; 
+
+	struct sigaction sa;
+
+	if (argc != 2) {
+		printf("Usage: %s <port number>\n",argv[0]);
+		exit(1);
+	}
+
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_NOCLDWAIT;
+	sa.sa_handler = SIG_DFL;
+	assert (sigaction(SIGCHLD, &sa, NULL) != -1);
+
+
+
+	listen_sock = socket(AF_INET, SOCK_STREAM, 0);
+	assert( listen_sock > 0);
+
+	assert (setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) != -1);
+
+
+
+	bzero(&server_addr, sizeof(server_addr));
+	server_addr.sin_family = AF_INET;
+	server_addr.sin_port = htons(atoi(argv[1]));
+	server_addr.sin_addr.s_addr = INADDR_ANY;
+	addr_len = sizeof(server_addr);
+
+	assert(bind(listen_sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr)) != -1);
+
+	assert(listen(listen_sock,10) == 0);
+
+
+
+	while(1){
+
+		service_sock = accept(listen_sock,
+				(struct sockaddr *)&client_addr , 
+				&addr_len);
+
+		assert(service_sock >= 0);
+
+		pid_t p = fork();
+		if (p==0){
+			close(listen_sock);
+			handle_transferred_file(service_sock,&client_addr);
+		}
+	}
+}
diff --git a/tp3/sophie-germain.sh b/tp3/sophie-germain.sh
new file mode 100755
index 0000000..1c9a233
--- /dev/null
+++ b/tp3/sophie-germain.sh
@@ -0,0 +1,14 @@
+#!/bin/bash
+min=4611686018427387904
+max=$((min + 20000))
+PRIMESIEVE="/export/documents/info/is1+2/asr/primesieve"
+
+$PRIMESIEVE $min -n 20000 > primes.txt
+
+while read q; do
+    echo "chargement"
+    p=$((2*q + 1))
+    if $PRIMESIEVE $p -n 1 | grep -q "^$p$"; then
+        echo "$p"  
+    fi
+done < primes.txt
diff --git a/tp3/test_df.c b/tp3/test_df.c
new file mode 100644
index 0000000..953181b
--- /dev/null
+++ b/tp3/test_df.c
@@ -0,0 +1,59 @@
+#include "df.h"
+#include "./lib_tea/xtea.h"
+
+#include <stdio.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdint.h>
+
+int main(int argc, char *argv[])
+{
+	uint64 p = 4611686018427402023,
+		   a,b,
+		   A,B,AB,BA,
+		   g;
+
+	uint32_t k[4]; // for tea
+				   //
+
+
+
+	g=generateur(p);
+	srand(getpid()^time(NULL));
+
+	for (int i = 0;i < 2; i++){
+
+		a = 2 + rand()%(p-3);
+		A=expm(g,a,p);
+
+		b = 2 + rand()%(p-3);
+		B = expm(g,b,p);
+
+
+		AB = expm(A,b,p);
+
+		BA = expm(B,a,p);
+		//printf("%lx %lx %lx %lx %lx %lx\n",a,b,A,B,AB,BA);
+		assert(AB == BA);
+
+		memcpy((void*)(k+2*i),(void*)&AB,sizeof(uint32_t)*2);
+	}
+
+	printf("key for tea = (%x,%x,%x,%x)\n",k[0],k[1],k[2],k[3]);
+
+
+
+	while(1){
+		uint32_t  v[2]={0};
+		ssize_t nb_read = read(0,v,sizeof(v));
+		if (nb_read <= 0)
+			break;
+		encrypt_xtea(v,k);
+		decrypt_xtea(v,k);
+		write(1,v,sizeof(v));
+	}
+	return 0;
+}