How to modify a method/field of Dalvik bytecode? about androguard HOT 9 CLOSED

Hi,

it's possible to modify a class file with androguard, but not yet a dex file 
(it's in my todo list, but not at the top :))

So if you would like to contribute to this feature, it will be cool :)

Thanks for the reply! I've cloned your project and tried to add the .dex 
modification support to .dvm. But as I do not have experience in reversing 
.dex, one problem is that I am kind of lost in the code :(. I've found the doc, 
which shows me a nice hierarchy of the code, and the inline comments are pretty 
helpful. And it will be very great if there is some other documents, such as 
notes about the basic functionality of each class, and the basic workflow. :)

The code follow the dex documentation, so I think you must read the 
documentation of the format :)

Sure. I was reading the code together with one document about dex file format. 
Hopefully I'll get into it quickly. :) Other than the body of the method 
itself, there is also index field as well as metadata, such as method index, 
local variable size, etc. So I guess I need to modify both the method body and 
these metadata at the same time to make it a valid .dex, right? 

Yes I think you must modify all variables which depends of the size of the 
method. And also you must modify the CFG.

Hi,

news ?:)

So sorry to say that there is little progress. I am now trying to modify the 
Dalvik interpreter to do the instrumentation. :)