MobileRead Forums - View Single Post - DRM: The bigger they are, the harder they fall

doctorow · 01-24-2006, 11:34 AM

Alex posted a flowchart how the eReader DRM might look like:
https://www.mobileread.com/forums/showthread.php?t=2367

I'm sure this is not the right place to discuss in detail how to crack DRM - MR guys would probably mind - but it should be obvious even to the layman how vulnerable eReader DRM is. Having disassembed and reverse-engineered eReader, one could write a tool that:

a) takes your credit card number and the filename of the protected book as inputs
b) prints the book in plaintext (or to be more precise: in Palm Markup Language (PML)) as output.

Sure, one could argue that the protection isn't fully cracked as it still requires a legit credit card number the book was originally encoded for. But that's how it is with public-private-key encryptions (such as RSA or El-Gamal) - if properly (!) implemented, there's no way how you can get around this problem then by using the original key (here: the cc number, or at least its hash code) to decrypt the file.

01-24-2006, 11:34 AM	#10
doctorow Guru Posts: 914 Karma: 3410461 Join Date: May 2004 Device: Kindle Touch	Alex posted a flowchart how the eReader DRM might look like: https://www.mobileread.com/forums/showthread.php?t=2367 I'm sure this is not the right place to discuss in detail how to crack DRM - MR guys would probably mind - but it should be obvious even to the layman how vulnerable eReader DRM is. Having disassembed and reverse-engineered eReader, one could write a tool that: a) takes your credit card number and the filename of the protected book as inputs b) prints the book in plaintext (or to be more precise: in Palm Markup Language (PML)) as output. Sure, one could argue that the protection isn't fully cracked as it still requires a legit credit card number the book was originally encoded for. But that's how it is with public-private-key encryptions (such as RSA or El-Gamal) - if properly (!) implemented, there's no way how you can get around this problem then by using the original key (here: the cc number, or at least its hash code) to decrypt the file.