I understand that you are never going to be able to stop the intended recipient keeping the image - that's trivial just with a screenshot, and anyone even capable / caring enough to run the linked code is going to defeat any further obfuscation you pile on.
What isn't clear to me from the link is: Is this same encryption the only protection applied to "snaps" that are in-flight? If I run my own wireless access point, can I use this code to decode all messages received by Snapchat users connected to my AP?
My understanding is, because they're kept on the disk, other apps can access them with no extra permissions - thus the reason they're "encrypted".
If you know the key, and because Snapchat will have to know where the files are, malware developers can write apps that scan the image directory, decrypt the files then send them to their own service.
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I don't fully understand this issue.
I understand that you are never going to be able to stop the intended recipient keeping the image - that's trivial just with a screenshot, and anyone even capable / caring enough to run the linked code is going to defeat any further obfuscation you pile on.
What isn't clear to me from the link is: Is this same encryption the only protection applied to "snaps" that are in-flight? If I run my own wireless access point, can I use this code to decode all messages received by Snapchat users connected to my AP?
My understanding is, because they're kept on the disk, other apps can access them with no extra permissions - thus the reason they're "encrypted".
If you know the key, and because Snapchat will have to know where the files are, malware developers can write apps that scan the image directory, decrypt the files then send them to their own service.
Yes the same encryption is on in-flight snaps. You could absolutely set up something like that.
Well that's just awful.