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White Paper
Technical issues to consider when wrapping with Softwrap.
Brendon Humphreys (Softwrap Research & Development) © 2002
Overview
This document describes what requirements are placed on software titles that are to be wrapped. The following technical pointers should be adhered to by the publisher of software that is to be Softwrapped.
Possible technical issues:
The program executable file must be a Microsoft Windows 32bit executable file, adhering to the Microsoft PE file format.
The program executable file will not do any self integrity checking, this includes CRC checking.
- Most installation files / self extracting zip files do some form of self integrity check to ensure that the installation will work correctly, and thus this check would fail if these files are wrapped.
The program executable must be wrapped, not the setup or installation executable file. i.e. If setup.exe is run to install a application called Softwaretitle then the file that must be wrapped is softwaretitle.exe and NOT setup.exe.
- The reason for this is if the setup file is wrapped with a trial period then the software application is unprotected as the setup file is only run once.
The software application should contain no copy protection other than Softwrap.
- The application should not attempt to ensure that a certain cd-rom is in the users cd-rom drive.
- The application must not make any assumptions as to the location of certain files (either on the hard drive or cd-rom disk).
No runtime compacting or unpacking is supported of the wrapped program executable file.
Once wrapped (fig 1), the installation process must include two additional files (the .sw and .locked files).
- For example - if Softwaretitle.exe is wrapped, the result will be three files namely Softwaretitle.exe, Softwaretitle.sw, Softwrap.dll file - and all of these files should be included in the installation file.
- The Softwaretitle.exe file is the encrypted Softwaretitle.exe file (the original file).
- The Softwaretitle.sw file is the license file.
- The Softwrap.dll file is the Softwrap Program containing the purchase wizards.
- Older versions of Softwrap produce a Softwaretitle.locked. file instead of the Softwrap.dll file.
The three files that are created during wrapping (i.e. the application.exe, application.sw and softwrap.dll files) are very tightly integrated and should under no circumstances be distributed individually; these three files must at all time be in the same folder.
- If any of these three files are not found; the program will refuse to execute, or an error will be displayed. See fig. 2 below.
- If one of the files are changed or corrupt an error will occur. See fig. 2 below.
The three files mentioned above should remain totally unchanged. No encryption or packing should be performed on these files once they have been created. However including these files in a self extracting file, or within a installation program is acceptable.
Fig. 1: Wrapping Process
Fig. 2: File integrity error
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