I noticed some of the same issues you did with the Wiki article, but didn't find a better general one. You? Cody Brocious had a blog post on the iTunes 6 process a while back but it doesn't seem to be available anymore...
Both the private assymetric key, used to communicate with the server (to obtain the symmetric keys) and all of the symmetric keys, used to decrypt the actual media files, are hidden inside iTunes. Try looking for them on your harddrive, I promise you that you won't find them (unless you are an expert pirate with a few months of your time where you have nothing better to do....)
My point was exactly that. All the keys for decryption have to be on your PC/Mac/iPod.
It's the keys used to encrypt the actual media files, which are more closely guarded at Apple. It's much easier to pick the locks on the local system you have under your control than a remote server somewhere... The decryption keys are definitely stored locally since you can play protected files while offline. The one chink in the armor that I see that Jon may be using is that the personalization of the files is done locally, so this step may be exploitable.
Finding where the keys are on your HDD is the easy part, accessing and using them is the task that takes months... [Simple way to find the location of the keys. Image your HDD. Purchase file from iTunes. Image your HDD compare the two images. The new key(s) (and the file itself) must be in the bits that changed.]
As someone who does this for a living, can you comment on my read of the hacks that have been released in the later post http://forums.macrumors.com/showpost.php?p=2917258&postcount=96. It still seems to me that where DRM has been hacked has relied on key retrieval or finding the weak spot in the chain.
Both the private assymetric key, used to communicate with the server (to obtain the symmetric keys) and all of the symmetric keys, used to decrypt the actual media files, are hidden inside iTunes. Try looking for them on your harddrive, I promise you that you won't find them (unless you are an expert pirate with a few months of your time where you have nothing better to do....)
My point was exactly that. All the keys for decryption have to be on your PC/Mac/iPod.
It's the keys used to encrypt the actual media files, which are more closely guarded at Apple. It's much easier to pick the locks on the local system you have under your control than a remote server somewhere... The decryption keys are definitely stored locally since you can play protected files while offline. The one chink in the armor that I see that Jon may be using is that the personalization of the files is done locally, so this step may be exploitable.
Finding where the keys are on your HDD is the easy part, accessing and using them is the task that takes months... [Simple way to find the location of the keys. Image your HDD. Purchase file from iTunes. Image your HDD compare the two images. The new key(s) (and the file itself) must be in the bits that changed.]
As someone who does this for a living, can you comment on my read of the hacks that have been released in the later post http://forums.macrumors.com/showpost.php?p=2917258&postcount=96. It still seems to me that where DRM has been hacked has relied on key retrieval or finding the weak spot in the chain.
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