note 21479 added to function.mcrypt-encrypt

From: Date: Tue, 14 May 2002 18:01:15 +0000
Subject: note 21479 added to function.mcrypt-encrypt
Groups: php.notes 
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here is an example of using this function in cfb mode: function encrypt_normal($key, $plain_text) { // returns encrypted text // incoming: should be the $key that was encrypt // with and the $plain_text that wants to be encrypted $plain_text = trim($plain_text); /* We need a way to generate a _unique_ initialization vector but at the same time, be able to know how to gather our IV at both encrypt/decrypt stage. My personal recommendation would be (if you are working with files) is to get the md5() of the file. In this example, however, I want more of a broader scope, so I chose to md5() the key, which should be the same both times. Note that the IV needs to be the size of our algorithm, hence us using substr. */ /* generate an initialization vector */ $iv = substr(md5($key), 0,mcrypt_get_iv_size (MCRYPT_CAST_256,MCRYPT_MODE_CFB)); /* now we do our normal encrypting */ $c_t = mcrypt_encrypt (MCRYPT_CAST_256, $key, $plain_text, "cfb", $iv); return trim(chop(base64_encode($c_t))); } -- http://www.php.net/manual/en/function.mcrypt-encrypt.php http://master.php.net/manage/user-notes.php?action=edit+21479 http://master.php.net/manage/user-notes.php?action=delete+21479 http://master.php.net/manage/user-notes.php?action=reject+21479

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