Quote:
Originally Posted by JohnTheRipper
Hi joblack,
I was debugging the script, and found that the error was because of the lenght of the book session key in line 1196 (v3 of the script). Maybe there's something wrong in RSA decrypting so that the decryption of the streams does not work.
The RSA decryption is based in the AES key generated by ineptkey script. Maybe is not an AES CBC_MODE key for PDF older versions. i♥cabbages said that uses AES in CBC mode with a random IV... or maybe is not RSA with PKCS#1 v1.5 padding, who knows?
All of these questions influence the dump method, because my "decrypted" PDF has the correct structure.
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The book session key problem is (most probably) solved. The Bookkey error could be still a problem.
IMHO this error only occures if you have registered and activated your ADE on a website where they gave you a RC4, DES, Tripple DES or RC2 instead of an AES with CBC.
see at:
The algorithms that shall be used to encrypt the enveloped data in the PKCS#7 object are: RC4 with key lengths up to 256-bits, DES, Triple DES, RC2 with key lengths up to 128 bits, 128-bit AES in Cipher Block Chaining (CBC) mode, 192-bit AES in CBC mode, 256-bit AES in CBC mode. The PKCS#7 specification is in Internet RFC 2315, PKCS #7: Cryptographic Message Syntax, Version 1.5 (see the Bibliography).
Anyway, only time will show if the bookkey error will be resistant (I never had one in my bought ebooks - if you still have one after trying out the new version drop me a line).