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Introduction

There are many kinds of cracks, but most of them involve a change to part of the code of the app. This is indicated by the cracker explaining the part of the code that has to be modified and the required modifications to the original hexadecimal chain to crack the app.

This is usually indicated by the cracker in this way:

    /nameoftheapp.app/Contents/MacOS/nameoftheapp
    md5: <A 32 characters (letters and numbers) block>

    •••• •••• •••• ••••              <-- original chain of hex values
    -->                              <-- change to
    •••• •••• •••• ••••              <-- new chain of hex values

    md5: <A different 32 characters (letters and numbers) block>

Or the cracker can write the chains of hex values in this way (pairs instead of groups of 4 characters):

    •• •• •• •• •• •• •• ••          <-- original chain of hex values
    -->                              <-- change to
    •• •• •• •• •• •• •• ••          <-- new chain of hex values

Or in this way (without blank spaces):

    ••••••••••••••••                <-- original chain of hex values
    -->                             <-- change to
    ••••••••••••••••                <-- new chain of hex values

To crack the app you should follow the next three steps:

1. Find the file to modify

/nameoftheapp.app/Contents/MacOS/nameoftheapp
indicates the path to the file that you have to modify (usually the main executable).
2. Check the MD5

md5
is the resulting "number" of a checksum of the file.

You can check the MD5 of your apps using Terminal or some drag and drop utilities, like:

- md5app (free): http://www.enigmarelle.com/sw/md5app/
- md5drop (free): http://www.h4-engineering.de/e_TECHNIK.html
- MD5shot (free): http://www.softyards.com/md5shot.html

Usually you'll have to check the MD5 of the main executable, which you can find in: Control-click the app/show package contents -> Contents/MacOS/nameoftheapp

If you want to use Terminal to check the MD5:

1. Launch Terminal and write:
md5
<blank space>
2. Drop the file over the Terminal window
3. Hit Enter
4. Terminal will output the MD5 sum

If you want to use any of the available MD5 checking utilities, just drag and drop the file on the utility icon, or launch the app and drag and drop the file on the window's app.

If the MD5 of the file that you are trying to crack is identical to the first MD5 indicated by the cracker proceed to Step 3. If the MD5 is not identical, the developer has modified the application. If the application has been modified the crack will most likely not work because the chains of hex values to modify would be different to the ones stated by the cracker.

The purpose of last MD5, indicated by the cracker, is for you to check if the crack was applied correctly. If you did it correctly, the resulting MD5 of the cracked app will be identical to the one stated by the cracker.

3. Apply the crack
To apply a crack you have to change all the
original chains of hex values
to the
new chains of hex values
stated by the cracker. To accomplish this, you can choose between several different hex-editing applications shown below:

- HexEdit (free): http://hexedit.sourceforge.net
- PeekIt (free): http://ravenware.com/sware/index.html#development
- HexEditor (free): http://www.ex-cinder.com/hexeditor.html)
- Resorcerer: http://www.mathemaesthetics.com/Res24Info.html

All of the hex-editing applications work in a similar way so choose that application that fits you the best. While in the hex-editing application, (1) open the app you are going to crack, (2) search for the
original chain of hex values
and then (3) change it to the
new chain of hex values
. Repeat this process until you have found and changed all the hex values indicated by the cracker in his/her guidelines. Once the changes are saved the app is cracked.