User's Manual

44
DATA[16] AES Key to use. The first key has index 0. The last key has index 19.
Output DATA[0-15] Protocol result.
Table 36
AES SCRAMBLE MODE command parameters
9.20 Errors
After a command, in the status entry in the communication may assume one of the following values:
Nome Valore Descrizione
ST_OK
0 Operation completed with success.
ST_NONE_KEY
-1 Device not found. This error is due by:
• SmartKey not correctly inserted in the Parallel or USB
port.
• Drivers not correctly installed.
• Wrong LABEL used.
ST_SYNT_ERR
-2 Syntax error in the command. This error is due by:
• One of the arguments of the command is invalid.
•
The command is not support by the specific model of
SmartKey used. For example you are trying to read the
memory of a SmartKey without memory.
• The command is prohibited in the current SmartKey
state. For example you are trying to write the memory
in a SmartKey with the memory Fixing flag set.
ST_LABEL_FAILED
-3 Wrong LABEL used. Depending on the command or on the
SmartKey model it may be returned this error or the
ST_NONE_KEY
error.
ST_PW_DATA_FAILED
-4 Wrong PASSWORD used.
ST_HW_FAILURE
-20 An integrity check on the hardware device is failed.
9.21 Some suggestions on using SmartKey's functions
Combined use of the listed functions enables you to set up protection criteria providing high security and flexibility.
However, we should make some minimum suggestions to ensure secure implementation of the protection.
•
Always use the LOCATING Mode to detect dongle presence. This will help you make the program
independent of the parallel port where the SmartKey dongle is installed
•
Use the SCRAMBLING mode, in different points of the program, with values different from those of the
Original Data: if the result of subsequent comparisons with the Scrambled Data is positive, you will be sure
that a dongle with your Id-Code is installed on the PC.
• If you are using programmable dongles, run a READING operation in different points of the program: you will
be able to compare the read values with the expected values, and ensure that the software being run is really
authorized thanks to the special programming of the installed SmartKey dongle.
•
Always remember that a security system has the same degree of vulnerability as its weakest component.
The chapter 10 introduces some further suggestions for secure implementation of the protection.