Or maybe not? It was easy to verify their claims. I created an account, purchased one magazine and downloaded their Windows desktop app from Microsoft Store.
Using Everything , I quickly found the folder containing the issue I just downloaded:. I tried to open one of the files, but I got the result I expected: encrypted PDF files, we meet again!
I usually start with reversing the network API, but this time I changed the process and started with decompiling the app first, because trying to decrypt the files is way more fun. Zinio app targets both Windows 8. NET Native and can be trivially decompiled. This time I used dnSpy , which is my new favorite tool for decompiling. The search returned only a few results, and one of them was this function in the ZinioReaderWin8. CryptoUtils class:. This looked like it would be a very quick game over for Zinio.
This function tells us that the PDF password is encrypted with AES-CBC using the bit key derived from parameters called deviceId and uuid initialization vector is passed via cipher parameter.
But where are all these parameters coming from? Here are the most important lines of the ParsePackingList function:. But what about the remaining parameters, deviceId and uuid? It turns out they are static values initialized in ZinioReaderWin8. InitDefaultSettings function:. That was all I needed from the decompiled application.
This part of the process was straightforward. Each request and response are self-contained XML documents, without custom HTTP status codes and headers; that made my job even simpler.
The client calls the libraryService to download the list of all purchased issues, and then issueData is called for each of them in order to retrieve all the data necessary to download it. However, they should reappear when you sign back in, without downloading. It may be by design, to keep you from cheating, if they dump everything into one big file, it's done to handle multiple Zinio accounts on the same computer so it only displays those items that belong to whichever user is signed in.
The tech at Zinio sent me a second email, with more non-answers. This morning, with a clear head and a cup of Joe, I attack it again, and it was all so clear. First, the reason all my magazines were gone after I signed out of Zinio and then signed back in is that a couple days before I had updated i.
So, when I signed out, I had been signed in for months under the old email address, and when I signed in using the new email, naturally there were no mags downloaded in that account. This is actually done intentionally by Zinio so that if you subscribe to multiple magazines, you have the option of having different IDs for each perhaps multiple users on a single device.
I am assuming the reason all this happened when I signed out was NOT because I was signing out of the Zinio service on line but rather signing out of the reader. But it is not obvious WHAT you are signing out of when you sign out. In that folder there are a bunch of folders with numbered names. It appears there is one folder per mag. In each mag folder, there are two files for each page of the magazine.
Why is this important? It isn't really, unless you are a bit obsessive about backing data up. I am, and I wanted to be sure these magazines were backed up. Granted you can always download them again from Zinio, but that assumes there is a Zinio. What if the decide they don't want to provide the service anymore for any of a bunch of reasons? Exactly right. As I posted a moment ago, the reason the mags "disappeared" is I had change my email address thus in effect creating a new account.
Now I have the mags on my system under both account names. Actually, it did download all 40 or mags again. All the files for all mags are now in two places on my computer I have a 20Mbps connection both up and down.
I agree with your logic, however the tech obviously either mislead me intentionally to prevent me from cheating as you say or doesn't know how his product works. Because each page of each mag has an swf file and a jpg file. They are not are "stored in the Zinio reader System files" as the tech told me. And that's cool - if they are concerned about security, I get it.
I wasn't trying to get something for nothing, I was just curious and wanted to be sure I was backing the files up. Plus, I didn't understand why I "lost" all my mags. Big Giveaway — Win prizes worth R3, For a better experience, please enable JavaScript in your browser before proceeding.
Does anyone know how I can print Zinio magazines that are protected from printing? I want to make them into pdf so I can read anywhere. Joined Feb 23, Messages 70, Why not just buy the dead tree paper version instead? But I would like to have an electronic archive of the magazines. How do I do that? In the xml file? Use at your own risk.
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