Guardant Time/ Net Time / Code Time are equipped with real-time clock which permit to limit the operating time of the protected application.
The logic of the time limiting technology resides in the fact that the algorithm’s workability depends on the dongle’s built-in timer (RTC).
You can implement various licensing policies affecting the operation of the protected application using the real-time clock:
| The application will be operational only upon activating the algorithm, which will occur at a specified date |
| The application will cease to operate upon deactivation of the algorithm, which will occur at a specified date |
| The period of application operation is limited by a time period set for the algorithm’s operation, aka the “lifetime”. The algorithm is activated at the first launch of the application and deactivated upon the expiration of the “lifetime” |
Setting the Time Dependency of the Algorithm
In the mask for a dongle with an RTC, select a hardware algorithm which will be further used for protection and execute the Edit | Field propertiesmenu command.
Important information
In autoprotection, the setting of time dependency makes sense only for the symmetric algorithm (GSII64 or AES type) and only the one that will be further used for protection.
Select the Time dependency tab in the Field properties dialog box that appears.
PICTURE
- Set the required time dependencies using the checkboxes (see detailed description in the table below). Write the mask into the dongle.
Time settings dialog box control elements:
| Interface elements | Description |
|---|---|
| Time of automatic activation checkbox | If the checkbox is set, the algorithm (and, consequently the protected application) will become operational only upon reaching the specified activation date |
| Combined entry field/calendar for setting the activation date | Setting the calendar date of hardware algorithm activation The date can be set directly in the entry field or using the calendar |
| Time of automatic deactivation checkbox | If the checkbox is set, the hardware algorithm (and, consequently the protected application) stops being operational right upon reaching the specified deactivation date |
| Combined entry field/calendar for setting the deactivation date | Setting the calendar date of the hardware algorithm deactivation |
| Algorithm lifetime checkbox | If the checkbox is set, the operating time of the hardware algorithm (and, consequently the protected application) will be limited to a specified period of time. The timer countdown will launch upon the first call of the algorithm (after the first application launch) |
| Algorithm operating period entry fields | Setting of the algorithm’s operating time frame in years:months:days:hours:minutes:seconds format |
| Algorithm changes every… checkbox | If this checkbox is set, the algorithm’s determinant will be constantly changing after a specified time frame, starting from the indicated date (see FlipTime) |
| Entry field, specifying the number of days when the algorithm will change | Setting the period of changing the algorithm’s determinant for FlipTime mechanism (in days) |
| Combined entry field/calendar for setting the first algorithm change date | Setting the calendar date of the activation of the FlipTime mechanism |
FlipTime. Changing the Algorithm’s Answers after a Set Time Frame
FlipTime technology is implemented in RTC dongles. It allows for automatically changing the values returned by the dongle’s algorithms once the set time arrives.
Important information
FlipTime technology is not applicable to Loadable code protected items in Guardant Code Time!
FlipTime is a mechanism modifying a part of the algorithm’s determinant once the date set during the programming session of the dongle is reached. When such a change does not occur only once, the determinant will continue changing after a set time frame (in days). Consequently, upon each change of the determinant, the algorithm will return other values in response to the same queries.
In order to use the FlipTime mechanism, the developer needs to know the answers that the algorithm will return in each case. In order to solve this task, the FlipTime.exe console utility was included in the developer’s kit. It generates arrays of questions and answers to the algorithm for each change of the determinant.
To activate FlipTime you need to:
- Select the required algorithm in the RTC dongle mask, execute the Edit | Field properties menu command and then select the Time dependencies tab in the dialog box that appears.
- Set the Algorithm changes every… checkbox and the period (in days) for changing the algorithm in the field that appears.
- Set the date when FlipTime will be triggered using the combination box/calendar.
- Save the mask and write it into the dongle (Dongle | Write into the dongle menu command).
Launch the FlipTime.exe utility and receive the arrays of questions and answers after each change of the determinant.
Important information
- FlipTime technology is designed for using with the Guardant API protection only. It cannot be used with autoprotection!
- You should use FlipTime with discretion. If an error occurs in the calculations when designing protection or in programming the dongle, it will be rather difficult to diagnose it and correct on the fly, when the dongle will be at the end user’s location.
FlipTime technology provides the developer with the opportunity to implement a very sophisticated protection strategy, when protection mechanisms will be transformed after a given time frame without any additional reprogramming of the dongle required.