diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -12,5 +12,8 @@ Cryptographie - Outils et algorithmes
- cm : [Chiffrements par bloc, algorithmes à clefs publiques](cours/crypto.pdf).
- tp : [Substitution-Permutation-Network](td_tp/tp2)
+#### Semaine 3
+- cm : [Algorithmes à clefs publiques](cours/crypto.pdf).
+- tp : [Diffie-Hellman](td_tp/tp3)
diff --git a/cours/crypto.pdf b/cours/crypto.pdf
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diff --git a/td_tp/tp3/README.md b/td_tp/tp3/README.md
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+## TP3
+
+> Le but du tp est de mettre en oeuvre une communication sécurisée entre
+> un client et un serveur, en deux phases :
+> - Echange d'une clé.
+> - Cryptage de la communication par un algorithme de chiffrement
+> symétrique à l'aide de la clé echangée. (XTEA pour ce tp)
+
+[Rappel de cours](../cours/crypto.pdf)
+
+### Diffie-Hellman
+<div align="center">
+<img src="./dh.png">
+</div>
+
+
+
+Le système (et sa sécurité) de Diffie-Hellman repose sur la difficulté
+pratique, pour des grands nombres, de calculer le logarithme discret
+dans un groupe multiplicatif $\mathbb{Z}_{p}^{*}$ avec $p$
+premier.
+
+On rappelle que lorsque $p$ est premier, $\mathbb{Z}_{p}^{*}$ est cyclique. Si $g$ est un générateur,
+tout élément $x\in \mathbb{Z}_{p}^{*}$ s'écrit (de manière
+unique) sous la forme
+\[
+x=g^a,\ \ 1\leq a \leq p-1
+\]
+
+<!--\\((\\mathbb{Z}_{p}^{\*},.)\\) est ismorphe au groupe additif
+\\((\\mathbb{Z}_{p-1},+)\\)-->
+
+Par définition, $a$ est le logarithme (discret) de $x$ dans la
+base $g$ noté
+\[
+a=\log_{g}(x)
+\]
+
+Le schéma en haut de la page illustre comment deux entités peuvent
+échangés une clef. Alice génére $p$, un générateur $g$. Il
+choisit un nombre aléatoire $a$ ($2\leq a\leq p-2$), et envoie
+à Bob le triplet $((p,g,g^a)$. Bob recoit le triplet, et choisit un
+nombre $b$. Il envoie à Alice $g^b$. La clé calculée par Alice,
+et Bob est
+
+\|
+(g^a)^b = (g^b)^a= g^{ab}
+\]
+
+Pour calculer la clé, il faut connaître $ab$. Or seuls $g^a$ et
+$g^b$ ont été échangés. Ce qui nous ramène au problème du
+logarithme discret qui est difficile en pratique pour des grands
+nombres.
+
+##### Votre travail
+
+Le but du tp est d'écrire un client/serveur TCP :
+
+- Le client et le serveur utilise Diffie-Hellman pour échanger une clé
+ sur 16 octets. On utilisera des nombres premiers de Sophie Germain.
+- Le client saisit un message de l'utilisateur, le chiffre avec XTEA,
+ et envoit le message chiffré.
+- Le serveur reçoit le message chiffré, le déchiffre, et l'affiche.
+
+1. Trouver un générateur peut-être long. En effet, tout ce qu'on l'on
+ sait sur l'ordre d'un élément de $\mathbb{Z}_p^{*}$, c'est
+ qu'il divise l'ordre du groupe, i.e $p-1$. Pour que la
+ vérification soit plus rapide, on s'interesse aux nombres premiers
+ dit de Sophie Germain. Ils ont la particularité d'être sous la
+ forme $2q+1$, avec $q$ premier. Ainsi, l'odre de
+ $\mathbb{Z}_{p}^{*}$ est $2q$. L'odre possible d'un
+ élément ne peut être que $2$, $q$ ou $2q$. Ce qui fait peu (combien) de
+ test à effectuer quand on cherche un générateur.
+
+ Ecrire un script à l'aide de la commande `primesieve` qui donne
+ tous les nombres premiers de Sophie Germain dans
+ $[2^{62},2^{62}+20000]$. (il faut quelques minutes. Assurez-vous
+ que votre shell permet de représenter de tels nombres. Comment ?)
+
+2. Ecrire les [fonctions](src/df.c) suivantes :
+ ```c
+ 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
+ ```
+ Testez ([test_df.c](src/test_df.c)) avec $p = 4611686018427402023$ pour trouver un
+ générateur.
+
+
+
+Remarque : pour la génération d'un grand nombre
+premier, utilisez le programme `primesieve` qsui se trouve dans
+
+```
+/export/documents/is1+2/asr
+```
+.
diff --git a/td_tp/tp3/dh.png b/td_tp/tp3/dh.png
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diff --git a/td_tp/tp3/src/Makefile b/td_tp/tp3/src/Makefile
new file mode 100644
index 0000000..306953a
--- /dev/null
+++ b/td_tp/tp3/src/Makefile
@@ -0,0 +1,13 @@
+all : test_df
+
+./lib_tea/tea.o : ./lib_tea/tea.c
+ gcc -c ./lib_tea/tea.c -o ./lib_tea/tea.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/tea.o
+ gcc -o test_df df.o test_df.o ./lib_tea/tea.o
diff --git a/td_tp/tp3/src/df.c b/td_tp/tp3/src/df.c
new file mode 100644
index 0000000..1e2ffa5
--- /dev/null
+++ b/td_tp/tp3/src/df.c
@@ -0,0 +1,23 @@
+#include "df.h"
+
+uint64 expm(uint64 m, uint64 e, uint64 mod)
+{
+ uint128 _r=1;
+ uint128 _m=(uint128)m;
+ uint128 _mod = (uint128)mod;
+
+
+ // TODO
+
+ return (uint64)_r;
+}
+
+uint64 generateur(uint64 p)
+{
+ uint64 g=2;
+ uint64 r=1;
+
+ // TODO
+}
+
+
diff --git a/td_tp/tp3/src/df.h b/td_tp/tp3/src/df.h
new file mode 100644
index 0000000..0aba99a
--- /dev/null
+++ b/td_tp/tp3/src/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/td_tp/tp3/src/lib_tea/tea.c b/td_tp/tp3/src/lib_tea/tea.c
new file mode 100644
index 0000000..f541848
--- /dev/null
+++ b/td_tp/tp3/src/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/td_tp/tp3/src/lib_tea/tea.h b/td_tp/tp3/src/lib_tea/tea.h
new file mode 100644
index 0000000..ba07355
--- /dev/null
+++ b/td_tp/tp3/src/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/td_tp/tp3/src/lib_tea/xtea.c b/td_tp/tp3/src/lib_tea/xtea.c
new file mode 100644
index 0000000..769af64
--- /dev/null
+++ b/td_tp/tp3/src/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/td_tp/tp3/src/lib_tea/xtea.h b/td_tp/tp3/src/lib_tea/xtea.h
new file mode 100644
index 0000000..8007875
--- /dev/null
+++ b/td_tp/tp3/src/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/td_tp/tp3/src/reseau/Makefile b/td_tp/tp3/src/reseau/Makefile
new file mode 100644
index 0000000..41ec6bf
--- /dev/null
+++ b/td_tp/tp3/src/reseau/Makefile
@@ -0,0 +1,13 @@
+all : clt srv
+
+clt.o:clt.c
+ gcc -c clt.c
+clt: clt.o
+ gcc -o clt clt.o
+srv.o : srv.c
+ gcc -c srv.c
+srv : srv.o
+ gcc -o srv srv.c
+
+
+
diff --git a/td_tp/tp3/src/reseau/clt.c b/td_tp/tp3/src/reseau/clt.c
new file mode 100644
index 0000000..048dbce
--- /dev/null
+++ b/td_tp/tp3/src/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/td_tp/tp3/src/reseau/clt_echo.c b/td_tp/tp3/src/reseau/clt_echo.c
new file mode 100644
index 0000000..75d9d96
--- /dev/null
+++ b/td_tp/tp3/src/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 != 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(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/td_tp/tp3/src/reseau/srv.c b/td_tp/tp3/src/reseau/srv.c
new file mode 100644
index 0000000..37c0bab
--- /dev/null
+++ b/td_tp/tp3/src/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/td_tp/tp3/src/reseau/srv_echo.c b/td_tp/tp3/src/reseau/srv_echo.c
new file mode 100644
index 0000000..4085576
--- /dev/null
+++ b/td_tp/tp3/src/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/td_tp/tp3/src/test_df.c b/td_tp/tp3/src/test_df.c
new file mode 100644
index 0000000..7567950
--- /dev/null
+++ b/td_tp/tp3/src/test_df.c
@@ -0,0 +1,59 @@
+#include "df.h"
+#include "./lib_tea/tea.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_tea(v,k);
+ decrypt_tea(v,k);
+ write(1,v,sizeof(v));
+ }
+ return 0;
+}