PHP encryption/decryption from text file

Question

this really has me stumped....

I'm messing around with encryption using PHP.

Using memory, everything is fine....

//encrypt the sensitive data
$encryptedData = encrypt($senstiveData, $theKey);

//decrypt the data
$decryptedData = decrypt($encryptedData, $theKey);

//print decrypted string
echo "<br>Decrypted String:" . $decryptedData;

i.e. the decrypted string: contains the correct value.

However, if I write the information out to file.. it breaks.

$orderFile = "orders.dat";
$fh = fopen($orderFile, 'a') or die("can't open file");
fwrite($fh, $keyCode . "\n");
$serializedArray = serialize($encryptedData); 
fwrite($fh, $serializedArray . "\n");
fclose($fh);

$file = fopen("orders.dat","r");

//key is first line in 'orders.dat'
$theKey = fgets($file);

//serialised array is second line...
$unserializedArray = unserialize(fgets($file));

$decryptedData2 = decrypt($unserializedArray, $theKey);

//print decrypted string
echo "<br>Decrypted String:" . $decryptedData2 . "<br>";

And... the answer is incorrect.

I've verified that the key and array used in both versions are identical (i.e. the reconstructed unserialized array contains the same values as before it was serialized), could something be getting lost in translation when I write to file?

Any ideas where I should start looking to debug this?

Any advice would be appreciated, Mitch.

I use encryption as well but I was't aware that there are PHP functions decrypt/encrypt. The functions I know and use are part of the mcrypt module and starts with mcrypt_ (e.g. mcrypt_decrypt). — Jens Bradler
– Jens Bradler, Commented Apr 29, 2012 at 4:37
Why are you using a \n in your fwrite function? Hard returns are extra bytes, which might throw off your encryption functions. — Marc
– Marc, Commented Apr 29, 2012 at 4:38

Marc · Accepted Answer · 2012-04-29 04:55:12Z

3

Remove the new-line character(s) from your fwrite(). I.e., don't do this:

fwrite($fh, $keyCode . "\n");

The \n can screw up the encryption/decryption routines.

This should be adequate:

fwrite($fh, $keyCode);

answered Apr 29, 2012 at 4:55

Marc

11.6k2 gold badges40 silver badges48 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

mitch_au Over a year ago

Thanks for your help Marc, I wasted 5 hours trying to figure that out!

Collectives™ on Stack Overflow

PHP encryption/decryption from text file

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related