by shigemk2

当面は技術的なことしか書かない

メモ MCRYPT_RIJNDAEL

こんらんするな

$ php -a
php > $td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, '');
php > print_r(mcrypt_enc_get_key_size($td));
32
php > print_r(mcrypt_enc_get_block_size($td));
16
php > $td = mcrypt_module_open(MCRYPT_RIJNDAEL_192, '', MCRYPT_MODE_CBC, '');
php > print_r(mcrypt_enc_get_key_size($td));
32
php > print_r(mcrypt_enc_get_block_size($td));
24
php > $td = mcrypt_module_open(MCRYPT_RIJNDAEL_256, '', MCRYPT_MODE_CBC, '');
php > print_r(mcrypt_enc_get_key_size($td));
32
php > print_r(mcrypt_enc_get_block_size($td));
32

すこしわかりやすく

php > $td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, '');
php > print_r(mcrypt_enc_get_key_size($td) * 8);
256
php > print_r(mcrypt_enc_get_block_size($td) * 8);
128
php >
php > $td = mcrypt_module_open(MCRYPT_RIJNDAEL_192, '', MCRYPT_MODE_CBC, '');
php > print_r(mcrypt_enc_get_key_size($td) * 8);
256
php > print_r(mcrypt_enc_get_block_size($td) * 8);
192
php >
php > $td = mcrypt_module_open(MCRYPT_RIJNDAEL_256, '', MCRYPT_MODE_CBC, '');
php > print_r(mcrypt_enc_get_key_size($td) * 8);
256
php > print_r(mcrypt_enc_get_block_size($td) * 8);
256

MCRYPT_RIJNDAELについて、ブロックの長さは選べるけど、鍵の長さは256bit固定なのね