doumie6223 2014-07-01 13:48
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I'm just trying some benchmark on hash functions and their speed and in one case I encoutred strange issue. Code is easy, i create hash from random number, then another hash from random and the i put this together with few serverand local values and take how much execution take.

I know that it's crazy code, nut it's just for benchmark and question is out of my curiosity:


$salt1 = hash( 'sha1', uniqid( mt_rand( 1, mt_getrandmax() ), true ) );
$token1 = hash( 'sha1', uniqid( mt_rand( 1, mt_getrandmax() ), true ) );
$token2 = hash( 'sha1', $_SERVER['HTTP_ACCEPT_ENCODING'] . $salt1 . $_SERVER['HTTP_ACCEPT_LANGUAGE'] . $token1 . $_SERVER['REMOTE_ADDR'] , true  );

After this code is finished I end up with time and values salt1, token1 and token2. I was not looking at values, but just from luck i encoutred this values:

$salt1 = e93edda7d1810efb661fe0b4eb85c92256516302
$token1 = ca43d77821ddc90b6b0bfebe1a20f1985547dbeb
$token2 = >)c³‡Ìq£Vé‘Æä¯ËÊü*

As you cen see, in token2 there is no hexa value. How is it possible if this function should return hexa values?

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  • douqiu9529 2014-07-01 13:55

    You have to remove the true at the end. Having this boolean parameter set to true as you can see from the documentation means that the output value is in raw binary format

    本回答被题主选为最佳回答 , 对您是否有帮助呢?



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