Public/Functions/New-RandomNumber.ps1
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function New-RandomNumber { <# .SYNOPSIS Generate a cryptographically secure number .DESCRIPTION Generate a cryptographically secure number based on System.Security.Cryptography.RNGCryptoServiceProvider .INPUTS [int]Minimum [int]Maximum .OUTPUTS [int] : Cryptographically secure random number .EXAMPLE # Will generate a random number between 0 and 2147483647 New-RandomNumber .EXAMPLE # Will generate a random number between 10 and 50 New-RandomNumber -Minimum 10 -Maximum 50 #> [CmdletBinding()] param ( <# Sets the minimum number that should be returned within a possible range #> [Parameter(Mandatory = $false, ValueFromPipelineByPropertyName = $true)] [ValidateRange(0, [int]::MaxValue)] [int]$Minimum = 0, <# Sets the maximum number that should be returned within a possible range #> [Parameter(Mandatory = $false, ValueFromPipelineByPropertyName = $true)] [ValidateRange(1, [int]::MaxValue)] [int]$Maximum = [int]::MaxValue ) begin { try { ################################# # Opening Message Write-Verbose -Message "Function Start: ""$($MyInvocation.MyCommand.Name)""" -Verbose:$VerbosePreference } catch { throw $PSItem } } process { ################################# # Variables try { $DebugAllEnabled = $null $DebugAllEnabled = $Global:DebugPreference -eq 'Continue' Write-Debug -Message "DebugAllEnabled: ""$($DebugAllEnabled)""" -Debug:$DebugPreference $VerboseAllEnabled = $null $VerboseAllEnabled = $Global:VerbosePreference -eq 'Continue' Write-Debug -Message "VerboseAllEnabled: ""$($VerboseAllEnabled)""" -Debug:$DebugPreference $DebugInternalEnabled = $null $DebugInternalEnabled = $PSBoundParameters.Debug.IsPresent -eq $true -or $DebugAllEnabled -eq $true Write-Debug -Message "DebugInternalEnabled: ""$($DebugInternalEnabled)""" -Debug:$DebugPreference $VerboseInternalEnabled = $null $VerboseInternalEnabled = $PSBoundParameters.Verbose.IsPresent -eq $true -or $VerboseAllEnabled -eq $true Write-Debug -Message "VerboseInternalEnabled: ""$($VerboseInternalEnabled)""" -Debug:$DebugPreference $ExternalCommandSplat = $null $ExternalCommandSplat = @{ Debug = $DebugAllEnabled ErrorAction = "Stop" Verbose = $VerboseAllEnabled } If ($DebugInternalEnabled -eq $true) { Write-Debug -Message "ExternalCommandSplat: $(ConvertTo-Json @ExternalCommandSplat -InputObject $ExternalCommandSplat)" -Debug:$DebugPreference } $InternalCommandSplat = $null $InternalCommandSplat = @{ Debug = $DebugInternalEnabled ErrorAction = "Stop" Verbose = $VerboseInternalEnabled } If ($DebugInternalEnabled -eq $true) { Write-Debug -Message "InternalCommandSplat: $(ConvertTo-Json @ExternalCommandSplat -InputObject $InternalCommandSplat)" -Debug:$DebugPreference } $BufferSize = $null $BufferSize = 4 Write-Debug @InternalCommandSplat -Message "BufferSize: ""$($BufferSize)""" } catch { Throw $PSItem } ################################# # Validate range try { if ($Minimum -ge $Maximum) { Throw "Invalid range: Minimum ""$($Minimum)"" must be less than Maximum ""$($Maximum)""." } } catch { Throw $PSItem } ################################# # Generate the random number try { Write-Verbose @InternalCommandSplat -Message "Creating the RNGCryptoServiceProvider object" $RNGCryptoServiceProvider = $null $RNGCryptoServiceProvider = New-Object @ExternalCommandSplat -TypeName "System.Security.Cryptography.RNGCryptoServiceProvider" Write-Verbose @InternalCommandSplat -Message "Creating a buffer of bytes" $Buffer = $null $Buffer = New-Object @ExternalCommandSplat -TypeName "byte[]" -ArgumentList $BufferSize Write-Verbose @InternalCommandSplat -Message "Getting bytes" $RNGCryptoServiceProvider.GetBytes($Buffer) Write-Verbose @InternalCommandSplat -Message "Getting random value" $RandomValue = $null $RandomValue = [BitConverter]::ToUInt32($Buffer, 0) Write-Verbose @InternalCommandSplat -Message "Setting the range" $Range = $null $Range = $Maximum - $Minimum Write-Verbose @InternalCommandSplat -Message "Generating the random number" $RandomNumber = $null $RandomNumber = $Minimum + $RandomValue % ($Range + 1) Write-Verbose @InternalCommandSplat -Message "Returning the random number" Write-Output @ExternalCommandSplat -InputObject $RandomNumber } catch { Throw $PSItem } } end { ################################# # Closing Message try { Write-Verbose -Message "Function End: ""$($MyInvocation.MyCommand.Name)""" -Verbose:$VerbosePreference } catch { Throw $PSItem } } } |