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Problem with PHP mcrypt function

I use the following function to decrypt data on my server:

function decrypt($key, $text) {
    return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key, base64_decode($text), MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND)));
}

I read a lot about NOT using ECB (and I know that it is deprecated, so you need to switch to CBC. Just switch the mode to:

function decrypt($key, $text) {
    return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key, base64_decode($text), MCRYPT_MODE_CBC, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CBC), MCRYPT_RAND)));
}

does not work. Errors are not generated, but the returned data is still encrypted.

What am I missing?

Updated code - still with errors:

$key = "hello"; 

$iv = mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC), MCRYPT_DEV_RANDOM);

function encrypt($key, $text) {
    return trim(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key, $text, MCRYPT_MODE_CBC, $iv)));
}


function decrypt($key, $text) { 
    return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $key, base64_decode($text), MCRYPT_MODE_CBC, $iv));
}


$text = 12345;

echo "Plain Number : " . $text . "<br><br>";

$encrypted = encrypt($key, $text);
echo "AES Number : " . $encrypted . "<br><br>";

echo "Plain Number : ". decrypt($key, $encrypted) . "<br><br>";

this should work, but it returns an error:

block in

blockize in> Warning: mcrypt_encrypt ()

[function.mcrypt-encrypt]: IV parameter should be until block inblocksize in

block in

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3 answers

$iv, , en-/decoding:

$key = "hello"; 

$iv = mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC), MCRYPT_DEV_RANDOM);

function encrypt($key, $text, $iv) {
    return trim(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key, $text, MCRYPT_MODE_CBC, $iv)));
}

function decrypt($key, $text, $iv) { 
    return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $key, base64_decode($text), MCRYPT_MODE_CBC, $iv));
}

$text = 12345;

echo "Plain Number : " . $text . "<br><br>";

$encrypted = encrypt($key, $text, $iv);
echo "AES Number : " . $encrypted . "<br><br>";

echo "Plain Number : ". decrypt($key, $encrypted, $iv) . "<br><br>";

$iv, :

function encrypt($key, $text) {
    global $iv; // or use $GLOBALS['iv] instead of $iv in the call below
    return trim(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key, $text, MCRYPT_MODE_CBC, $iv)));
}

function decrypt($key, $text) { 
    global $iv; // or use $GLOBALS['iv] instead of $iv in the call below
    return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $key, base64_decode($text), MCRYPT_MODE_CBC, $iv));
}

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+5

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+7

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+3

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