Created
January 31, 2011 02:49
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A toy cypher written in PHP. (I have no idea why I wrote this...)
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<?php | |
function xor_cipher($data, $key) { | |
$data = bitify($data); | |
$key = bitify($key); | |
$cipher = array(); | |
$k_i = 0; | |
for($d_i=0; $d_i<count($data); $d_i++) { | |
$d = $data[$d_i]; | |
$k = $key[$k_i]; | |
$c = $d ^ $k; | |
$cipher[] = $c; | |
$k_i<(count($key)-1)?$k_i++:$k_i=0; | |
} | |
return unbitify($cipher); | |
} | |
function bitify($data) { | |
$final = array(); | |
for($i = 0; $i < strlen($data); $i++) { | |
$char = $data[$i]; | |
$ord = ord($char); | |
$byte = sprintf('%08b', $ord); | |
for($j = 0; $j < 8; $j++) { | |
$bit = $byte[$j]; | |
$final[] = intval($bit); | |
} | |
} | |
return $final; | |
} | |
function unbitify($data) { | |
$final = ''; | |
for($i = 0; $i < count($data); $i+=8) { | |
$byte = implode(array($data[$i], $data[$i+1], $data[$i+2], $data[$i+3], $data[$i+4], $data[$i+5], $data[$i+6], $data[$i+7])); | |
$ord = bindec($byte); | |
$char = chr($ord); | |
$final .= $char; | |
} | |
return $final; | |
} | |
function swizz_cipher($data, $key) { | |
$data = bitify($data); | |
$key = bitify($key); | |
$cipher = array(); | |
$k_i = 0; | |
for($d_i=0; $d_i<count($data); $d_i++) { | |
$d = $data[$d_i]; | |
$k = $key[$k_i]; | |
$p = $d_i>0?$cipher[$d_i-1]:0; | |
$t = $k ^ $p; | |
$c = $d ^ $t; | |
$cipher[] = $c; | |
$k_i<(count($key)-1)?$k_i++:$k_i=0; | |
} | |
return unbitify($cipher); | |
} | |
function swizz_decipher($cipher, $key) { | |
$cipher = bitify($cipher); | |
$key = bitify($key); | |
$f_key = array(); | |
$k_i = 0; | |
foreach($cipher as $bit) { | |
$f_key[] = $key[$k_i]; | |
$k_i<(count($key)-1)?$k_i++:$k_i=0; | |
} | |
$r_cipher = array_reverse($cipher); | |
$r_key = array_reverse($f_key); | |
$data = array(); | |
$k_i = 0; | |
for($d_i=0; $d_i<count($r_cipher); $d_i++) { | |
$t = $d_i<(count($r_cipher)-1)?$r_cipher[$d_i+1]:0; | |
$c = $r_cipher[$d_i]; | |
$k = $r_key[$d_i]; | |
$p = $t ^ $k; | |
$d = $p ^ $c; | |
$data[] = $d; | |
} | |
$r_data = array_reverse($data); | |
return unbitify($r_data); | |
} | |
$data = "Hello, world!"; | |
$key = "ola"; | |
$cipher = swizz_cipher($data, $key); | |
$decipher = swizz_decipher($cipher, $key); | |
var_dump($decipher); |
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