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  #1  
Old 09-09-2004, 08:14
thewhiz
 
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A vague question will only garner a vague response -- anything is possible, it all depends on your will and ultimate ability. Further, it depends on the capabilities of the "demo" if it is full featured or is it crippled further.
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  #2  
Old 09-09-2004, 08:34
JMI JMI is offline
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As thewhiz has stated, you have not provided enough information for anyone to give you an informative response, except to suggest basic principles. You state the program will run for 30 days and is a "demo" version. This creates a number of possibilities from a reversing prospect.

1. The program is complete and has some form of protection which keeps track of the passage of time to know when the 30 days have passed and then disables itself in some way. This would be your "best case" version of the software. Then you would need to learn how programs keep track of the fact that they have been installed, where such information might be hidden, and then how to locate such information and remove it and disable the programs attempts to call this "time keeping" routine, so that you can use it as long as you want, without this limitation. If you succeed at this quest, you will have a fully functional program without limitation.

2. The program is not complete because some of the functions of the code are not included and it has a method of keeping track of the passage of time or operation of the program and disables itself when the "limit" is reached. If this is the case, then even if you figure out how to disable the checks that the program makes to determine that it has been installed and run for the "limit" time, you still don't have a fully functioning program. In this case, you can still figure out how the program keeps track of its checks of time or operation and disable them, but you will never have a fully functioning program.

Many programs use software made by others, generally called "protection software" to provide their efforts to prevent 'crackers" from getting the full program without the limitations. Others write their own. Some rely only on software protection for this prupose, and some rely on mechanical devices, such as dongles which have to be installed on your machine to make the program operate properly.

There are some pre-existing software which attempts to defeat certain protection programs. They work with more or less effectiveness. There are tools, both software and mechanical, which are used to attempt to defeat these protection measures.

Barring the use of "ready made" solutions, one needs to know substantial information about the disassembly of software programs, how to use the tools which accomplish this task, what the code they view with these tools is doing and how the code might be altered to, instead, do what one wants, rather than what the original programmer wanted it to do.

In short, no matter what your program does and/or how it does it, if YOU are intending to accomplish the task of "reversing" the protection system, YOU have a long journey ahead of you and it is one where, just like life, you have to learn how walk before you can run and you have to study before you can comfortably believe you know what the heck you are doing.

So. Where do you want to begin?

Regards,
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JMI
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  #3  
Old 09-09-2004, 09:30
ur next
 
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In fact, I think I'm getting a little ahead of myself and I definately agree with you on the fact that
Quote:
just like life, you have to learn how walk before you can run and you have to study before you can comfortably believe you know what the heck you are doing
It's just that I'm so excited about learning all this, that I want to get everything lined-up and ready to start learning! I do appreciate you taking the time to explain some of these important points. I have been reading a lot of info on some outdated tutorials that I found on the web (1999,2000) but I'm sure if I keep at it, I'll find what I need and eventually will get started.
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  #4  
Old 09-09-2004, 15:08
shn0r
 
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There are many apps which are download able from www, and they are protected by dongles so beware
Look into help of this app, topic registration or etc if author says that they will give u a link or send by emaill full installation of this app after u buy it must be demo but if this demo have only 30 days trial it can be cracked
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  #5  
Old 09-10-2004, 10:51
ur next
 
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As a matter of fact I did some exploring on this target, and found out that in fact, that you have to call them and then they will give you a password to upgrade thru their website. so I guess I'll try another one.

Also, I'm trying to see If I can find some good targets I can reverse with Ollydbg instead of SoftIce, being that it sounds more complicated. I'll Keep you guys in touch.
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  #6  
Old 09-11-2004, 06:11
Michel Michel is offline
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Hi ur next,

Maybe it would be easier for you to begin working with IDA on "dead listing" :
If your file isn't packed, you have a good chance to see some messages like " Enter serial number", "Invalid serial number, please try again ", " days left"... and so you can go up, find the calls, the conditional jumps etc.

Trying to determine what the prog is doing "on the paper" will be a very good exercise for your intuition and asm knowledje...

"Dead listing" methode go naturally to patching the prog : you can for sample bypass the test verifying a date or a serial, but if you want to find THE working serial, this methode is often very hard : it is more usefull to work with a debugger like Ollydbg.
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