convert exec openssl to php openssl commands - php

Question

Attempting to use dynamic encryption for Paypal on my local WAMP 2.4 server. Openssl is installed in Apache and enabled in PHP. Using exec Openssl fails. Can anyone provide some suggestions or if you feel real generous the code for converting the following PHP code to PHP Openssl requests (preferred method)? BTW I've tried both OPENSSL file pointers, both are found but neither works.
function paypal_encrypt($hash)
{
//Sample PayPal Button Encryption: Copyright 2006-2010 StellarWebSolutions.com
//Not for resale - license agreement at
//http://www.stellarwebsolutions.com/en/eula.php
$MY_KEY_FILE='paypal/encrypt/myprivate_key.pem';
$MY_CERT_FILE='paypal/encrypt/mypublic_cert.pem';
$PAYPAL_CERT_FILE='paypal/encrypt/paypal_cert.pem';
$OPENSSL='../../bin/apache/Apache2.4.4/bin/openssl.exe';
$OPENSSL='../../bin/apache/Apache2.4.4/conf/openssl.cnf';
if (!file_exists($MY_KEY_FILE)) {
echo "ERROR: MY_KEY_FILE $MY_KEY_FILE not found\n";
}
if (!file_exists($MY_CERT_FILE)) {
echo "ERROR: MY_CERT_FILE $MY_CERT_FILE not found\n";
}
if (!file_exists($PAYPAL_CERT_FILE)) {
echo "ERROR: PAYPAL_CERT_FILE $PAYPAL_CERT_FILE not found\n";
}
if (!file_exists($OPENSSL)) {
echo "ERROR: Openssl $OPENSSL not found\n";
}
//Assign Build Notation for PayPal Support
$hash['bn']= 'StellarWebSolutions.PHP_EWP2';
$data = "";
foreach ($hash as $key => $value) {
if ($value != "") {
//echo "Adding to blob: $key=$value\n";
$data .= "$key=$value\n";
}
}
echo $data;
$openssl_cmd = "($OPENSSL smime -sign -signer $MY_CERT_FILE -inkey $MY_KEY_FILE " .
"-outform der -nodetach -binary <<_EOF_\n$data\n_EOF_\n) | " .
"$OPENSSL smime -encrypt -des3 -binary -outform pem $PAYPAL_CERT_FILE";
exec($openssl_cmd, $output, $error);
if (!$error) {
return implode("\n",$output);
} else {
return $error."ERROR: encryption failed";
}
}

Answer 1

I have successfully done it with couple of hours of trying and searching. Finally found this very helpful article
Simplified Code Below
function paypal_ewp_encrypt_data( $hash, $certs ){
$temp_files_dir_path = ''; // a directory php have write access where we will write temporary files and delete afterwards.
$data = 'cert_id=' . $certs->paypal_cert_id;
foreach ($hash as $key => $value) {
if ($value != "") {
$data .= "\n$key=$value";
}
}
$unique_id = uniqid(time());
$data_file_in = $temp_files_dir_path . DIRECTORY_SEPARATOR . $unique_id . "-data-in.txt"; // raw data fie
$data_file_out = $temp_files_dir_path . DIRECTORY_SEPARATOR . $unique_id . "-data-out.txt";// signed data file
$enc_file_out = $temp_files_dir_path . DIRECTORY_SEPARATOR . $unique_id . "-enc-out.txt"; // encrypted data file
$fp = fopen( $data_in, "w" );
fwrite($fp, $data);
fclose($fp);
if( ! openssl_pkcs7_sign(
$data_file_in, $data_file_out, 'file://' . $certs->public_key,
array( 'file://' . $certs->private_key, ''),
array(),
PKCS7_BINARY)
){
return false;
}
$data_out_data = explode("\n\n", file_get_contents($data_out));
$out = fopen($data_out, 'wb');
fwrite($out, base64_decode($data_out_data[1]));
fclose($out);
if( ! openssl_pkcs7_encrypt(
$data_file_out, $enc_file_out,
'file://' . $certs->paypal_public_key, array(),
PKCS7_BINARY, OPENSSL_CIPHER_3DES )
){
return false;
}
$en_data = explode("\n\n", file_get_contents($enc_file_out) );
$en_data = $en_data[1];
$en_data = "-----BEGIN PKCS7-----" . str_replace("\n", "", $en_data ) . "-----END PKCS7-----";
// delete files
#unlink($data_file_in);
#unlink($data_file_out);
#unlink($enc_file_out);
$paypal_array = array(
'cmd' => '_s-' . $hash['cmd'], // use _s- before the cmd
'encrypted' => $en_data
);
}
function certs(){
$certs = new stdClass();
$certs->public_key = '' // absolute path to your public key file
$certs->private_key = '' // absolute path to your private key file
$certs->paypal_public_key = '' // absolute path to paypal public key file
$certs->paypal_cert_id = '' // given cert id after you upload the public key to paypal website.
}
Implementation
$hash = array(
// key value pair of paypal form variables
);
$certs = certs();
$data = paypal_ewp_encrypt_data($hash, $certs);
Data is a php array of key value pair require to create the form fields. Use key as name and value as field value.