Chilkat HOME .NET Core C# Android™ AutoIt C C# C++ Chilkat2-Python CkPython Classic ASP DataFlex Delphi ActiveX Delphi DLL Go Java Lianja Mono C# Node.js Objective-C PHP ActiveX PHP Extension Perl PowerBuilder PowerShell PureBasic Ruby SQL Server Swift 2 Swift 3,4,5... Tcl Unicode C Unicode C++ VB.NET VBScript Visual Basic 6.0 Visual FoxPro Xojo Plugin
(Chilkat2-Python) Exporting and Importing Accumulated EntropyWhen a system starts, a good established source of entropy may be lacking. The Fortuna algorithm keeps 32 internal entropy pools. When AddEntropy is called, it is added to these internal pools. (The details of the Fortuna algorithm can be read elsewhere.) This example demonstrates how the entropy that has accumulated within the internal pools can be exported (such as when an application exits) and then imported when an application starts. (It is the application's job to persist the exported entropy to a database, file, etc.) Importing entropy helps ensure an application is beginning with an adequate source of entropy for random number generation.
import sys import chilkat2 # All Chilkat classes can be unlocked at once at the beginning of a program # by calling UnlockBundle. It requires a Bundle unlock code. chilkatGlob = chilkat2.Global() success = chilkatGlob.UnlockBundle("Anything for 30-day trial.") if (success != True): print(chilkatGlob.LastErrorText) sys.exit() fortuna = chilkat2.Prng() # Generate random data and periodically add entropy... success = fortuna.AddEntropy(fortuna.GetEntropy(32,"hex"),"hex") print(fortuna.GenRandom(16,"hex")) print(fortuna.GenRandom(16,"hex")) print(fortuna.GenRandom(16,"hex")) success = fortuna.AddEntropy(fortuna.GetEntropy(16,"hex"),"hex") print(fortuna.GenRandom(16,"hex")) print(fortuna.GenRandom(16,"hex")) print(fortuna.GenRandom(16,"hex")) success = fortuna.AddEntropy(fortuna.GetEntropy(16,"hex"),"hex") print(fortuna.GenRandom(16,"hex")) print(fortuna.GenRandom(16,"hex")) print(fortuna.GenRandom(16,"hex")) success = fortuna.AddEntropy(fortuna.GetEntropy(16,"hex"),"hex") print(fortuna.GenRandom(16,"hex")) print(fortuna.GenRandom(16,"hex")) print(fortuna.GenRandom(16,"hex")) exportedEntropy = fortuna.ExportEntropy() # The application would persist the exported entropy in some way, # such as to a file, or to a database, etc. # Create a new PRNG object and initialize the internal entropy pools # with the previously exported entropy: fortuna2 = chilkat2.Prng() success = fortuna2.ImportEntropy(exportedEntropy) # Generate more random data, continuing to add entropy as we go along.. print(fortuna2.GenRandom(16,"hex")) print(fortuna2.GenRandom(16,"hex")) print(fortuna2.GenRandom(16,"hex")) success = fortuna2.AddEntropy(fortuna2.GetEntropy(16,"hex"),"hex") print(fortuna2.GenRandom(16,"hex")) print(fortuna2.GenRandom(16,"hex")) print(fortuna2.GenRandom(16,"hex")) success = fortuna2.AddEntropy(fortuna2.GetEntropy(16,"hex"),"hex") # .. |
© 2000-2024 Chilkat Software, Inc. All Rights Reserved.