Cannot verify IAP receipt from Windows Store

[bugant]

I am trying to verify receipt from Windows Store using Ruby. I'am using the xmldsig gem as follows:

certificate = OpenSSL::X509::Certificate.new(cert)
signed_document = Xmldsig::SignedDocument.new(xml)
signed_document.validate(certificate)

but it fails using the data taken from MS example (which is working in C#).

I've also asked for help on SO, if you would like to contribute to the discussion there.

[Chelo]

Hi! I have this problem too!, did you find some answer? I have been searching but I don't find nothing :(

[bugant]

@Chelo still nothing here! I haven't been able to validate a Windows Store receipt using Ruby.

[benoist]

http://stackoverflow.com/questions/18823837/verify-iap-receipt-from-windows-store-using-php
Looking at this URL it could indicate that you need to strip the whitespace completely

ops, i missed out that you need a $dom->preserveWhiteSpace = false; before $dom->loadXML to make the DigestValue match – Elf Yang Oct 9 '13 at 10:10

[bugant]

@benoist I've tried to add

xml = xml.gsub("\n", "")
xml = xml.gsub(" ", "")

but still I got that the receipt is not valid.

[bugant]

@benoist the following worked:

xml = xml.gsub(/^\s+/, '').gsub(/\s+$/, '').gsub(/\n/, '')

Many thanks to @potomak that helped solving the issue. \CC @Chelo

[benoist]

Great, I'll put a link to this issue in the Readme :)

[bugant]

@benoist I was thinking about crafting a little gem to verify Windows in-app receipts usign xmldsig.

[Chelo]

@bugant @benoist this works!!! thanks for your help guys 👍