PHP加密解密实例分析
本文实例讲述了PHP加密解密方法。分享给大家供大家参考，具体如下：
//加密
function string2secret($str)
{
$key = "123";
$td = mcrypt_module_open(MCRYPT_DES,'','ecb','');
$iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
$ks = mcrypt_enc_get_key_size($td);
$key = substr(md5($key), 0, $ks);
mcrypt_generic_init($td, $key, $iv);
$secret = mcrypt_generic($td, $str);
mcrypt_generic_deinit($td);
mcrypt_module_close($td);
return $secret;
}
//解密
function secret2string($sec)
{
$key = "123";
$td = mcrypt_module_open(MCRYPT_DES,'','ecb','');
$iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
$ks = mcrypt_enc_get_key_size($td);
$key = substr(md5($key), 0, $ks);
mcrypt_generic_init($td, $key, $iv);
$string = mdecrypt_generic($td, $sec);
mcrypt_generic_deinit($td);
mcrypt_module_close($td);
return trim($string);
}
echo secret2string(string2secret("11111111111111111"));
//显示结果是11111111111111111
echo '<br>'.string2secret("11111111111111111");
//显示乱码
echo '<br>';
//$string:要加密的字符串 $isEncrypt=true:加密 $isEncrypt=false:解密
function dencrypt($string, $isEncrypt = true, $key = "KEY_SPACE") {
if (!isset($string{0}) || !isset($key{0})) {
return false;
}
$dynKey = $isEncrypt ? hash('sha1', microtime(true)) : substr($string, 0, 40);
$fixedKey = hash('sha1', $key);
$dynKeyPart1 = substr($dynKey, 0, 20);
$dynKeyPart2 = substr($dynKey, 20);
$fixedKeyPart1 = substr($fixedKey, 0, 20);
$fixedKeyPart2 = substr($fixedKey, 20);
$key = hash('sha1', $dynKeyPart1 . $fixedKeyPart1 . $dynKeyPart2 . $fixedKeyPart2);
$string = $isEncrypt ? $fixedKeyPart1 . $string . $dynKeyPart2 : (isset($string{339}) ? gzuncompress(base64_decode(substr($string, 40))) : base64_decode(substr($string, 40)));
$n = 0;
$result = '';
$len = strlen($string);
for ($n = 0; $n < $len; $n++) {
$result .= chr(ord($string{$n}) ^ ord($key{$n % 40}));
}
return $isEncrypt ? $dynKey . str_replace('=', '', base64_encode($n > 299 ? gzcompress($result) : $result)) : substr($result, 20, -20);
}
echo strlen(dencrypt("12345678912345"));
希望本文所述对大家PHP程序设计有所帮助。