openssl_pkey_export and "cannot get key from parameter 1"

Question

I need to use openssl within my php project, so I created a test php page using openssl. However, I keep getting these errors and I am not sure why. openssl is enabled.

Warning: openssl_pkey_export() [function.openssl-pkey-export]: cannot get key from parameter 1 in C:\wamp\www\opensslsample\index.php on line 18

Warning: openssl_pkey_get_details() expects parameter 1 to be resource, boolean given in C:\wamp\www\opensslsample\index.php on line 21

<?php
 //echo phpinfo();

   $privateKey = openssl_pkey_new(array(
'private_key_bits' => 1024,
'private_key_type' => OPENSSL_KEYTYPE_RSA,
));

openssl_pkey_export($privateKey, $privkey,"123");

$pubkey=openssl_pkey_get_details($privateKey);
$pubkey=$pubkey["key"];
?>

Answer 1

This may help if you are on windows:

1. Click on the START button
2. Click on CONTROL PANEL
3. Click on SYSTEM AND SECURITY
4. Click on SYSTEM
5. Click on ADVANCED SYSTEM SETTINGS
6. Click on ENVIRONMENT VARIABLES
7. Under "System Variables" click on "NEW"
8. Enter the "Variable name" OPENSSL_CONF
9. Enter the "Variable value". My is - C:\wamp\bin\apache\Apache2.2.17\conf\openssl.cnf
10. Click "OK" and close all the windows and RESTART your computer.

The OPENSSL should be correctly working.

Answer 2

Check openssl_error_string. My guess is that your openssl.cnf file is missing or something.

Alternatively, you could use phpseclib, a pure PHP RSA implementation, to generate keys. eg.

<?php
include('Crypt/RSA.php');

$rsa = new Crypt_RSA();

extract($rsa->createKey());

echo "$privatekey<br />$publickey";
?>