Aescu

1) Keygen
2) Usefull breackpoints


KeyGens ... 

Useful tips: 

 1. The best tool to analyze a key file is an Hex Editor. Text editor are not suitable for this task. 
 2. A key file is nothing more than a continuous array of bytes inside a small file. These bytes reflect the personal user
information (encrypted), checksums of the key file integrity, encrypted dates, 
names, addresses, encrypted flags (for instance: a flag for multi-user license), etc. 
 3. To defeat a Key File Based protection scheme, you should create a little program to code a small bogus key file. This
generic program should be able to create files under different names a sizes. The content of this bogus file (against most
believes) must be readable information. In my 
case, the bogus key file generator, cuts a large chapter from my favorite literature novel and paste it in the bogus file, adjusting
the file size and name according to my necessities. Why readable information inside the bogus file? because the target program
will read strategic offset locations of the key file. A readable text inside it will warn about the precise location being read at any
time. It will also mark the locations where certain checksums must be added to the final key file. 
 4. The key file name is in most cases, the target program main executable file name with the extension '*.key'. A very old
stupidity flag still available these days. Other strategies to figure out the key file name, are the use of a string searching utility,
reading the user's manual (sometimes the author will include instructions on the key file installation, revealing its name), at
debugging level, bpint 21 if ah==3d (DOS), when the break occurs, execute: d (e)dx at SoftICE command screen, in windows
environment, bpx CreatFile, ReadFile, GetFileAttributesA, etc., will perform the same task. 
Once you have figured out the key file name, create the bogus file and copy it to the same path as the main target executable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     