如何在PHP中加密/解密整数

Question

有没有办法对整数(或字符串)进行2路加密/解密--请注意，我不是在寻找编码

我需要这样的东西

密码(100) -> 24694 密码(101) -> 9564jh4或45216或gvhjdfT或其他. 解密(24694) -> 100

我不需要编码，因为它是双向的

base64_encode(100) ->MTAw base64_encode(101) ->MTAx

我希望我能在这里找到一种加密/解密纯数字的方法(计算机热爱数字，速度更快)

Answer 1

function decrypt($string, $key) {
$result = '';
$string = base64_decode($string);
for($i=0; $i<strlen($string); $i++) {
$char = substr($string, $i, 1);
$keychar = substr($key, ($i % strlen($key))-1, 1);
$char = chr(ord($char)-ord($keychar));
$result.=$char;
}
return $result;
}

function encrypt($string, $key) {
$result = '';
for($i=0; $i<strlen($string); $i++) {
$char = substr($string, $i, 1);
$keychar = substr($key, ($i % strlen($key))-1, 1);
$char = chr(ord($char)+ord($keychar));
$result.=$char;
}
return base64_encode($result);
}

Answer 2

你有没有试过调查腐-13

更严肃的答案:从这所以答案，您可以使用：

function numhash($n) {
    return (((0x0000FFFF & $n) << 16) + ((0xFFFF0000 & $n) >> 16));
}

numhash(42);           // 2752512
numhash(numhash(42));   // 42

Answer 3

64位支持负数支持。还有一点安全盐。

@Petr Cibulka

class NumHash {

  private static $SALT = 0xd0c0adbf;

  public static function encrypt($n) {
    return (PHP_INT_SIZE == 4 ? self::encrypt32($n) : self::encrypt64($n)) ^ self::$SALT;
  }

  public static function decrypt($n) {
    $n ^= self::$SALT;
    return PHP_INT_SIZE == 4 ? self::decrypt32($n) : self::decrypt64($n);
  }

  public static function encrypt32($n) {
    return ((0x000000FF & $n) << 24) + (((0xFFFFFF00 & $n) >> 8) & 0x00FFFFFF);
  }

  public static function decrypt32($n) {
    return ((0x00FFFFFF & $n) << 8) + (((0xFF000000 & $n) >> 24) & 0x000000FF);
  }

  public static function encrypt64($n) {
    /*
    echo PHP_EOL . $n . PHP_EOL;
    printf("n   :%20X\n", $n);
    printf("<<  :%20X\n", (0x000000000000FFFF & $n) << 48);
    printf(">>  :%20X\n", (0xFFFFFFFFFFFF0000 & $n) >> 16);
    printf(">>& :%20X\n", ((0xFFFFFFFFFFFF0000 & $n) >> 16) & 0x0000FFFFFFFFFFFF);
    printf("=   :%20X\n", ((0x000000000000FFFF & $n) << 48) + (((0xFFFFFFFFFFFF0000 & $n) >> 16) & 0x0000FFFFFFFFFFFF));
    /* */
    return ((0x000000000000FFFF & $n) << 48) + (((0xFFFFFFFFFFFF0000 & $n) >> 16) & 0x0000FFFFFFFFFFFF);
  }

  public static function decrypt64($n) {
    /*
    echo PHP_EOL;
    printf("n   :%20X\n", $n);
    printf("<<  :%20X\n", (0x0000FFFFFFFFFFFF & $n) << 16);
    printf(">>  :%20X\n", (0xFFFF000000000000 & $n) >> 48);
    printf(">>& :%20X\n", ((0xFFFF000000000000 & $n) >> 48) & 0x000000000000FFFF);
    printf("=   :%20X\n", ((0x0000FFFFFFFFFFFF & $n) << 16) + (((0xFFFF000000000000 & $n) >> 48) & 0x000000000000FFFF));
    /* */
    return ((0x0000FFFFFFFFFFFF & $n) << 16) + (((0xFFFF000000000000 & $n) >> 48) & 0x000000000000FFFF);
  }
}

var_dump(NumHash::encrypt(42));
var_dump(NumHash::encrypt(NumHash::encrypt(42)));
var_dump(NumHash::decrypt(NumHash::encrypt(42)));

echo PHP_EOL;


// stability test

var_dump(NumHash::decrypt(NumHash::encrypt(0)));
var_dump(NumHash::decrypt(NumHash::encrypt(-1)));
var_dump(NumHash::decrypt(NumHash::encrypt(210021200651)));
var_dump(NumHash::decrypt(NumHash::encrypt(210042420501)));

下面是一步一步的步骤(删除注释)：

210042420501
n   :          30E780FD15
<<  :    FD15000000000000
>>  :              30E780
>>& :              30E780
=   :    FD1500000030E780

n   :    FD1500000030E780
<<  :          30E7800000
>>  :    FFFFFFFFFFFFFD15
>>& :                FD15
=   :          30E780FD15
int(210042420501)