How To Create Alias Files

Developing Applications Using The SoftwareShield System > Creating Licensing Solutions > Creating A License Project > How To Create Alias Files

## How To Create Alias Files

Creating great alias files is a simple matter of understanding the principles of alias files. You should already have read the section explaining: What Are Alias Files?

#### Creating Great Hidden Alias Files

To create great hidden alias files there are few simple points:

1. Use a file name that looks inconspicuous to most users. Dlls, OCXs, etc. are particularly good choices because generally only software developers will be able to actually determine if the binary contents of these files are not actually executable code. The hidden alias file contents are encrypted and compressed, so the contents is just as illegible as binary program code. An example hidden alias file name is "ctrlsyst.ocx".

2. Use a file name that you are reasonably sure will not clash with an existing file name on any system. For example if you invent the hidden alias file name "ctrlsyst.ocx", you should do a search on the Internet to see if by chance this is actually a real ocx, and if so - change it.

3. If your target user will typically have permission to write to the system directory, put the file location there. That is where most innocuous files like dlls and ocx are placed and it will blend in well. NOTE: if your user does not have write permissions for your location folder, the license will fail. It is always safer to use your Main License File Folder as you will have already determined that you can write there. See the section on Windows Permissions and Security Considerations for more information.

#### Creating Great Registry Alias Files

An important consideration here is that you do not cause a clash in GUID that you enter. To be sure that you do not cause this clash, always generate the GUIDs using the generate button on the Alias License File Tab. Generated GUIDs are guaranteed to be unique across space and time. (Space means generated in part based on unique attributes of different machines and time means generated in part based on the exact time and date). You should also carefully consider which root key you use based on your target user and Windows Permissions and Security Considerations.

#### Creating Great Steganographic Alias Files

To create great steganographic alias files there are few simple points:

1. Use a 24 bit per pixel image that is full color, windows format.

2. Be sure the image contains a reasonable level of detail and contrast. For example an image that is simply a single red dot on a white background does not have sufficient detail. However, a red and blue circular logo with some text on a white background will be sufficient.

3. Use an image that is between 64 x 64 and 128 x 128 pixels in size. Any smaller and it may not be able to hold the information, larger and it will take a long time to process.

4. Be sure that the name you enter in the Alias License File Tab is the exact name of the image (without the path information).