Symmetric hardware algorithms GSII64 and AES128 are implemented in Guardant dongles. They perform hardware encryption of small volumes of data*. See Section Hardware Algorithms for more information on symmetric algorithms.
Previously encrypted data can be stored in a protected application or separate files and decrypted right before use.
GrdCrypt function is used for calling a symmetric algorithm from within the application. See Guardant API help system (GrdAPI.chm) for more information on Guardant API operations.
GrdUtil.exe provides an easy-to-use service for preparing the encryption data in advance. You can encrypt and decrypt information using this utility. The prepared data is further used for application protection.
Preparation of data for encryption
Performing encryption
Clicking [Execute] button located in the top part of the dialog box initiates the encryption.
Writing mask data into dongle memory
Saving report
After that the encryption report saving dialog box will appear on the screen where filename (report.rep by default) and path should be specified.
The encryption report is a text file generated according to the syntax rules of the selected programming language. The report contains statistical information on encryption parameters & sets password in the form of array:
PICTURE
Process of encryption
After saving the report a progress bar will appear on the screen.
The encrypted data are saved in the specified file in the form of array or sequence of bytes.
Decryption
The process of decryption is similar to the process of encryption (see above). The input data here is a file with encrypted data. The direction of encryption is changed to decryption (Command list).
Important information
For correct decryption of data you need to use the same algorithm, an initialization vector and method of encryption that were used for encryption.