• Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other Pie Elite all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Liutauras Vilda
  • Tim Cooke
  • Paul Clapham
  • Jeanne Boyarsky
Sheriffs:
  • Ron McLeod
  • Frank Carver
  • Junilu Lacar
Saloon Keepers:
  • Stephan van Hulst
  • Tim Moores
  • Tim Holloway
  • Al Hobbs
  • Carey Brown
Bartenders:
  • Piet Souris
  • Frits Walraven
  • fred rosenberger

Tools required for changing byte-code

 
Ranch Hand
Posts: 120
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi...

I really don�t know if this advance java question

I happen to support an application written long back...1999 I suppose, basically the developers have left the company
There is no source code avaliable in company CVS and the class files are scrambled using some file name scrambler tool.

My Requirement is

1.) I have particular module of code in the application that does a authentication based on a hash value embedded into the code itself, I don't know what hashing algorithms is being used nor the exact password to match that hash value.

2.) I have decompiled the code using JAD but as the JAD was unable to create a full class file it generated some byte code also.

3.) I need modify the particular class file at byte-code level to change the flow that particular authentication call is alone skipped.

How can I change the byte-code? The nice thing is that I need to change in only one class file

May be even skip that particular authentication routine itself or set the default return value as true for any input irrespective of the hash being matched

I just in a spur of a moment promised my manager that I will resolve this issue, but I find it tough to proceed further.

I will be gratefully for any help or directions to any byte code editor tools
 
Rancher
Posts: 43028
76
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
For starters, you might try a different decompiler. JODE (on SourceForge) does a better job than JAD, so that may solve your problem. Try that first, before you delve into examining or modifying class files.
 
It means our mission is in jeapordy! Quick, read this tiny ad!
the value of filler advertising in 2021
https://coderanch.com/t/730886/filler-advertising
reply
    Bookmark Topic Watch Topic
  • New Topic