DPS Pxpay Fail Proof Result Notification (FPRN) failing

Hi guys,

I have a zencart site that's been running for ages, but it recent times there has been more occurrences of DPS payments showing up in the bank account without a corresponding order in Zen Cart.

After much investigation by Payment Express, myself and my web host, we're left scratching our heads a bit.

First off I've checked the permissions of dps_pxpay_result_handler.php and can confirm that they're 755

What happens on checkout is we're redirected to the DPS page, enter the card details and once the transaction is complete DPS sends the http GET (FPRN) to the web server, which then returns a 404 error.

If the user clicks the next button on the DPS page, the exact same http GET (although from the users IP address rather than the DPS server) is sent which returns a 302 and successfully completes the payment and checkout process.

Note: the problem here is we want the FPRN to work incase the user doesn't click next or has a problem with their browser.

This is the FPRN which gets a 404 response:

203.207.60.XXX - - [20/Sep/2012:16:53:09 +1200] "GET /dps_pxpay_result_handler.php?result=v51Hma1nTBEraTNJgxFD8M55mugVx0zFr8eJLA0IPwMw4oIaCuZdKWj2oVkvqV5iS9_FUZkXSn9rCq9TJLhhImeTwUPJ9Z3Dv0cvyMgwADHNd-1gzFxQTjFkGszSCCBw_B62RbLHemrYsOqhNQPbN_dPx-On0cbsw8R7Mom5yxxM8TrMcdfrxJNp2MF_QNCQGRx_z6_WBE0ner9xCMfZtsE6-1YfU_rmoz_fcJmXQP36kf7iiZnvBOQgQsca2rckfZBw6HXAUG0CN0L6vjMAybDibKQAv7F67Ggb2N9E3CWv_7sMF8N9OFNVvZwMLqfN3e2lWXZPVChufrFuBZDRQtVO7wE2y8EzuA-mnJtttbGxB7g6tl2Bz7m0nCnwH3rjRTGqw3ERsMkMJUqKMEVFnmk18PiGVbjI6SrS94IYzGtthIcEeWzXhIBOJ5DCdc217-TEWUniO3t1b9xlfivIGMsTxX7QYHVjDlAGxXsHH0q2Wn8wb0jfnWaSVxz8PrXJIQTY4l06QaQm5_CzcBM5HFfPRTGm3kmBdPa7kJt9_ng3Q=&userid=Fxxxxx HTTP/1.1" 404 465 "-" "PXL1"

and this is the successful GET that happens after the user clicks 'next' on the DPS payments page:

121.72.214.XXX - - [20/Sep/2012:16:53:39 +1200] "GET /dps_pxpay_result_handler.php?result=v51Hma1nTBEraTNJgxFD8M55mugVx0zFr8eJLA0IPwMw4oIaCuZdKWj2oVkvqV5iS9_FUZkXSn9rCq9TJLhhImeTwUPJ9Z3Dv0cvyMgwADHNd-1gzFxQTjFkGszSCCBw_B62RbLHemrYsOqhNQPbN_dPx-On0cbsw8R7Mom5yxxM8TrMcdfrxJNp2MF_QNCQGRx_z6_WBE0ner9xCMfZtsE6-1YfU_rmoz_fcJmXQP36kf7iiZnvBOQgQsca2rckfZBw6HXAUG0CN0L6vjMAybDibKQAv7F67Ggb2N9E3CWv_7sMF8N9OFNVvZwMLqfN3e2lWXZPVChufrFuBZDRQtVO7wE2y8EzuA-mnJtttbGxB7g6tl2Bz7m0nCnwH3rjRTGqw3ERsMkMJUqKMEVFnmk18PiGVbjI6SrS94IYzGtthIcEeWzXhIBOJ5DCdc217-TEWUniO3t1b9xlfivIGMsTxX7QYHVjDlAGxXsHH0q2Wn8wb0jfnWaSVxz8PrXJIQTY4l06QaQm5_CzcBM5HFfPRTGm3kmBdPa7kJt9_ng3Q=&userid=Fxxxxx HTTP/1.1" 302 542 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_2) AppleWebKit/536.26.14 (KHTML, like Gecko) Version/6.0.1 Safari/536.26.14"

According to my eyes, the only differences between the two GET's are the source IP address and the user agent / OS info.

in the dps_pxpay.php module the comments on line 72 suggest that FPRN is supported

// support for fail proof result notification
$this->_dpsResultRedirect = ('true' == ENABLE_SSL ? HTTPS_SERVER : HTTP_SERVER) . DIR_WS_HTTPS_CATALOG . 'dps_pxpay_result_handler.php';
// without
#$this->_dpsResultRedirect = zen_href_link(FILENAME_CHECKOUT_PROCESS, '', 'SSL', false);

Any ideas about how to resolve this issue?

Thank you,

Brendon

Why are the IP addresses different?

The first one (fprn) which fails is sent from the DPS server.

The second one which succeeds is initiated from the customers browser. In the case of this test it was my public IP address as I was the customer.

Is this something that happens EVERY time?

If not, what's unique to the times that it does happen vs the times when it does not?

A "404" response means "not found" ... which means that your webserver couldn't find the file when the visitor attempted to access that URL.

Yes this happens EVERY time the fprn is sent.

I did change the handler script to 777 for testing and that returned a 500 (internal server error) EVERY time. Weird.

I'm using the px pay module, and believe its something in the module code that is causing the error; just haven't been able to figure out what :-(

Has anyone else got the dps fprn working with Zencart?

bhscott:

Yes this happens EVERY time the fprn is sent.Okay, then the 404 errors should be recorded in the apache server errorlog, along with the reason for the 404.
Probably a result of some firewall or security rule or maybe an .htaccess rule blocking traffic from that source.
Your hosting company should be able to explain further. Or at the very least provide you with the errorlog entries for all those 404 reports.
bhscott:

I did change the handler script to 777 for testing and that returned a 500 (internal server error) EVERY time. Weird.Again, your hosting company should be able to tell you immediately that those 500 responses are a direct result of setting the file to 777 permissions, specifically because your hosting company has configured the server to do exactly that when 777 permissions are found. It's a security thing.

bhscott:

Has anyone else got the dps fprn working with Zencart?
I don't think that's an accurate or fair question, since your first post suggests that it did indeed work for you at one point, but has since stopped working. And that sort of thing would be a result of something changing on the server.