Quote:
Originally Posted by sirbruce
The PID is not "part" of the DRM scheme. It's a public identification number used as a reference key. The fact that it's somewhat obscured on the Kindle is irrelevant. [...].
|
Quote:
Originally Posted by Nate the great
@Thomas
Also, you seem to have conflated the kindlepid and kindlefix scripts. These are 2 separate pieces of code.
Just so you know, [...] The DRM is not touched; it will continue to function as designed.
|
Bruce your point is partly right, and the wrong part is likely based on a wrong assumption. Nate - you are also correct (except I don't exactly know what conflate means). In my orginal post, I had the detail wrong.
I think the "key" is to decide what you mean by "DRM" - the whole scheme, or just the last parts pertaining to actual book content.
Let me try again, and for those of you being dragged through the weeds - I am wondering (not concluding) if you should reconsider some your assumptions about kindlefix in light of what it really does and what the DMCA says. Of course, if you don't care about DRM issues, never mind. On the other hand, if you are taking some high moral ground to respect DRM, and also loving kindlefix, you may have a logic problem in your head. Or, maybe not. I don't decide for you.
Based on a recollection of kindlefix.py, here is how I understand mobi DRM to work.
The "DRM" is indeed based on PIDs. PIDs are not private; yes, they have become more obscure over time. (users once entered PIDs into the mobipocket web-site before downloading content)
Mobi files contain key-records in addition to encrypted content. The key-records are also encrypted.
A key-record holds a PID (representing a device), a set of DRM rights for that PID, and the key to decrypt the content.
To "adjust" the DRM for a book on a device, one of the book's key-records must contain the device PID.
Step 1: kindlepid helps you determine a device's PID.
Step 2: kindlefix decrypts key-records in a book until it finds one matching the PID whose DRM rights need adjustment.
It adds "Kindle read" permission (dw4|0x800)(?) to the key-record for that PID, re-encrypts the key-record, and replaces the key-record in the mobi file.
It is correct that kindlefix does not access the book content.
So my question is whether kindlefix as used in step two is prohibited "circumvention" in the context of DMCA cited earlier. It is decrypting part of the book file.