Adobe ADEPT DRM for PDF circumvented

[joblack]

Originally Posted by JohnTheRipper

This is the encrypted key:

<encryptedKey>PDN/JFFoDC6XKdI1SOeOA3uLtgbaRmvGPf9gSwQOVOMvq3YQS/yDnTnx+oQoXR9lZF+V/pbGZ
g6UktG8iGSKG/6HrgyHIfnDo+6G4jqeX/0EEUunPS6O+h3SP56cvThtyaxVv0ayXhserM9cFY89KTTxcK0U bso0H4cqirlWR1c=</encryptedKey>

taken from the base64-decoded rights of the uncompressed ADEPT_LICENSE's xml. Then it applies an rsa decrypt, but it seems not to be correct. The ebx_V and ebx_type seems to be get ok (3 and 6). Actually, ineptpdf v2 decrypts but streams seems to be corrupted (i.e. not correctly decrypted) so I can see pages like in ADE.

Sure ILC has made a extremely good job, but part of the script is based on PDFParser from pdfminer..

I have no time now to reverse-engineer what ADE does when opens a DRM, it uses CRYPT32.DLL and CryptUnprotectData...

----------------

PDFMiner v20090824.
dumppdf said:

raise PDFEncryptionError('Unknown filter: param=%r' % param)
pdfminer.pdfparser.PDFEncryptionError: Unknown filter: param={'EBX_SELLER_URL': '', ...
... , 'Filter': /EBX_HANDLER, 'Length': 128, 'EBX_PUBLISHER_URL': '', 'V': 3}

RSA isn't used to decrypt the whole pdf it's only to decrypt the symmetric key (the former would be too slow). I know it comes from pdf miner but pdf miner has no dump method and almost no cryptological methods.

[JohnTheRipper]

I mean that RSA is applied to the key; the whole pdf is supposed to be rc4 encrypted.

I think the problem is in initialize_ebx, not in dump. I don't understand when :

if ebx_V < 4 or ebx_type < 6:
V = ord(bookkey[0])
bookkey = bookkey[1:]

this produces (shorten bookkey length from 16 to 15) the error because the length doesn't match (not equal to 16)..

[caterpillar]

Hi all! I'm new to this forum. I applied ineptpdf for my McGraw-Hill ebook and I got:

· ineptpdf v2 => said "successfully decrypted" but it contained only blank-pages
· ineptpdf v3 => said "error decrypting book session key"
· ineptpdf v4 => said "error decrypting book session key"

Any help would be appreciated!

[JohnTheRipper]

We are discussing right now about the problem. What pdf version and EBX_HANDLER version do you have in your PDF?

I have the same problem and no solution yet

[caterpillar]

Hi Johntheripper, thank you for your response! My pdf file uses 128 bit EBX_HANDLER and PDF-1.3.

[userman]

Hi,

for decrypt a ebook I need decrypt it from the pc/buy? because when i buy a ebook i can decryp it with inetpdf but when i get a ebook buyed from another computer i can not decrypt.

(sorry for my bad english)

[wallcraft]

Originally Posted by userman

for decrypt a ebook I need decrypt it from the pc/buy? because when i buy a ebook i can decryp it with inetpdf but when i get a ebook buyed from another computer i can not decrypt.

The way it is supposed to work is that you can decrypt any PDF bought for the same AdobeID as your PC. A single AdobeID can be associated with 6 devices (Windows PCs or Macs or EInk Readers). If the other computer was registered to another AdobeID, then your key won't work to decrypt it.

[userman]

wallcraft sure, I know it now.

Thanks.

[roger64]

So you can only decrypt your own DRMed files for interoperability purposes.
Sounds fair. And it works nicely.

[JohnTheRipper]

Originally Posted by roger64

So you can only decrypt your own DRMed files for interoperability purposes.
Sounds fair. And it works nicely.

Not all DRMed PDFs are currently possible to decrypt... the book session key error remains

Some of us are waiting for a new version of the ineptpdf that solves this problem

[roger64]

OK. I did not do extensive trials.

On the epubfront, I got an excellent result with the v.2 version of the script and I failed with v.3. I don't know why.

[JohnAppleseed0]

I don't think any update is forthcoming. The author has disappeared, and no one here seems really capable of solving the situation

[elfwood]

Since I'm a total tech idiot, here's the dumb question of the day.
There are times that I'd like to switch an epub or adobe pdf ebook from one computer to another. Is there any way to do that?

Sometimes I could just return the book to the library, then check it out on the other laptop. But that won't work if there is a waiting list.

Still crabby about the epub font mess. I'd really like to have more control over the font choices--the way it is with adobe pdf--especially since the e-library I use seems only to be buying epub now.

elle

[conant]

As I noticed that the scripts were no longer existed. Anyone can pm me an address? Much appreciation!~

[krischik]

Originally Posted by conant

As I noticed that the scripts were no longer existed. Anyone can pm me an address? Much appreciation!~

Well there is a very interesting thread at Mobipocket which might enlighten you.

Yes, still there, still not censored.

Martin