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|
int encrypt(
void* buffer,
int buffer_len, /* Because the plaintext could include null bytes*/
char* IV,
char* key,
int key_len
){
int i = 0;
MCRYPT td = mcrypt_module_open("rijndael-256", NULL, "cbc", NULL);
int blocksize = mcrypt_enc_get_block_size(td);
if( buffer_len % blocksize != 0 ){
return 1;
}
mcrypt_generic_init(td, key, key_len, IV);
mcrypt_generic(td, buffer, buffer_len);
mcrypt_generic_deinit (td);
mcrypt_module_close(td);
return 0;
}
int decrypt(
void* buffer,
int buffer_len,
char* IV,
char* key,
int key_len
){
MCRYPT td = mcrypt_module_open("rijndael-256", NULL, "cbc", NULL);
int blocksize = mcrypt_enc_get_block_size(td);
if( buffer_len % blocksize != 0 ){
return 1;
}
mcrypt_generic_init(td, key, key_len, IV);
mdecrypt_generic(td, buffer, buffer_len);
mcrypt_generic_deinit (td);
mcrypt_module_close(td);
return 0;
}
void display(char* ciphertext, int len){
int v;
for (v=0; v<len; v++){
printf("%d ", ciphertext[v]);
}
printf("-\n");
}
int main()
{
char plaintext[SIZE + 1] = {0};
char key[SIZE_PWD + 1] = {0};
int rtn = 0;
MCRYPT td, td2;
char* IV;
int keysize = 16; /* 128 bits */
char* buffer;
int buffer_len = 0;
int i = 0;
int choix = 0;
td = mcrypt_module_open("rijndael-256", NULL, "cbc", NULL);
IV = malloc(mcrypt_enc_get_iv_size(td));
for (i=0; i< mcrypt_enc_get_iv_size( td); i++) {
IV[i]=rand();
}
printf("Saisir le pwd :\n");
do
{
rtn = scanf(" %"XSTR(SIZE_PWD)"[^\n]", key);
clean_stdin();
}
while (rtn != 1);
keysize = strlen(key);
printf("Saisir le texte :\n");
rtn = 0;
do
{
rtn = scanf(" %"XSTR(SIZE)"[^\n]", plaintext);
clean_stdin();
}
while (rtn != 1);
buffer_len = strlen(plaintext);
buffer = calloc(1, buffer_len);
strncpy(buffer, plaintext, buffer_len);
do {
printf("\nSaisir le choix (0 crypter, 1 décrypter, 2 quitter) :\n");
scanf("%d", &choix);
if(choix == 0 ){
printf("plain: %s\n", plaintext);
encrypt(buffer, buffer_len, IV, key, keysize);
printf("cipher: ");
display(buffer , buffer_len);
printf("IV :%x-", IV);
}
else if( choix == 1 ){
printf("Saisir le pwd :\n");
do
{
rtn = scanf(" %"XSTR(SIZE_PWD)"[^\n]", key);
clean_stdin();
}
while (rtn != 1);
keysize = strlen(key);
printf("Saisir le texte :\n");
rtn = 0;
do
{
rtn = scanf(" %"XSTR(SIZE)"[^\n]", plaintext);
clean_stdin();
}
while (rtn != 1);
buffer_len = strlen(plaintext);
buffer = calloc(1, buffer_len);
strncpy(buffer, plaintext, buffer_len);
fflush(stdin);
printf("Saisir l'IV :\n");
rtn = 0;
do
{
rtn = scanf(" %"XSTR(SIZE)"[^\n]", IV);
clean_stdin();
}
while (rtn != 1);
display(buffer , buffer_len);
decrypt(buffer, buffer_len, IV, key, keysize);
printf("decrypt: %s\n", buffer);
}
} while( choix != 2);
free(IV);
free(buffer);
return 0;
} |
