Implementation of PHP encryption algorithm reversible encryption algorithm and decryption sharing _php tutorial

The encryption algorithm is as follows:
Copy CodeThe code is as follows:
function Encrypt ($data, $key)
{
$key = MD5 ($key);
$x = 0;
$len = strlen ($data);
$l = strlen ($key);
for ($i = 0; $i < $len; $i + +)
{
if ($x = = $l)
{
$x = 0;
}
$char. = $key {$x};
$x + +;
}
for ($i = 0; $i < $len; $i + +)
{
$str. = Chr (Ord ($data {$i}) + (Ord ($char {$i}))% 256);
}
Return Base64_encode ($STR);
}

The decryption algorithm is as follows:
Copy the Code code as follows:
function Decrypt ($data, $key)
{
$key = MD5 ($key);
$x = 0;
$data = Base64_decode ($data);
$len = strlen ($data);
$l = strlen ($key);
for ($i = 0; $i < $len; $i + +)
{
if ($x = = $l)
{
$x = 0;
}
$char. = substr ($key, $x, 1);
$x + +;
}
for ($i = 0; $i < $len; $i + +)
{
if (Ord (substr ($data, $i, 1)) < Ord (substr ($char, $i, 1))
{
$str. = Chr ((Ord ($data, $i, 1) + substr)-Ord (substr ($char, $i, 1)));
}
Else
{
$str. = Chr (Ord (substr ($data, $i, 1))-Ord (substr ($char, $i, 1)));
}
}
return $str;
}

The process of encrypting and decrypting above requires the use of an encryption key (i.e., parameter $key).

Copy the Code code as follows:
$data = ' PHP encryption and decryption algorithm '; Information that is encrypted
$key = ' 123 '; Secret key
$encrypt = Encrypt ($data, $key);
$decrypt = Decrypt ($encrypt, $key);
echo $encrypt, "\ n", $decrypt;

The above output will look similar to the following results:
Copy the Code code as follows:
Gnicsozzg+hns9zcfea7sefnghxf
PHP Encryption and decryption algorithm

As can be seen from the above results, this is a set of reversible encryption and decryption algorithms that can be used to encrypt some data that needs to be restored.

http://www.bkjia.com/PHPjc/726031.html www.bkjia.com true http://www.bkjia.com/PHPjc/726031.html techarticle The encryption algorithm is as follows: The copy code code is as follows: function Encrypt ($data, $key) {$key =md5 ($key); $x =0; $len =strlen ($data); $l =strlen ($key); for ($i = 0; $i $len; $i + +) {if ($x = = ...

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