CyCrypto.ps1
|
<#
Calculates a SHA256 HMAC for the given message and secret. Returns a string with the Base64 URL encoded result. #> function Get-HMACSHA256 { Param( [parameter(Mandatory=$true)] [String]$message, [parameter(Mandatory=$true)] [String]$secret ) $hmacsha = New-Object System.Security.Cryptography.HMACSHA256 $hmacsha.key = [Text.Encoding]::UTF8.GetBytes($secret) $messageBytes = [Text.Encoding]::UTF8.GetBytes($message) $signatureBytes = $hmacsha.ComputeHash($messageBytes) ConvertTo-Base64UrlEncoding $signatureBytes } <# Creates a JWT Token to authenticate to the Cylance console API. Can accept additional claims to include in request. #> function Get-CyJWTToken { Param ( [parameter(Mandatory=$True)] [Hashtable]$claims = @{}, [parameter(Mandatory=$true)] [String]$secret, [parameter(Mandatory=$true)] [String]$iss, [parameter(Mandatory=$true)] [String]$APIid, [parameter(Mandatory=$true)] [String]$tid, [parameter(Mandatory=$true)] [int]$expirationSeconds ) # calculate token mandatory fields $now = [int32](((Get-Date -Date ((Get-Date).ToUniversalTime()) -UFormat %s -Millisecond 0)) -Replace("[,\.]\d*", "")) $exp = $now + $expirationSeconds $guid = [guid]::newguid() $sub = $APIId $jti = $guid [pscustomobject]$registeredClaims = @{ sub = $sub iss = $iss jti = $jti exp = $exp tid = $tid iat = $now } $payload = $registeredClaims # merge additional private claims into payload $claims.Keys | ForEach-Object { Add-Member -InputObject $payload -Name $_ -Value $claims[$_] # $payload.Add($_ , $claims[$_]) } # header specifies algorithm + token typen [pscustomobject]$h = @{ alg = "HS256" typ = "JWT" } # get compact JSON representation of header + payload $h_json = $h | ConvertTo-Json -Compress $p_json = $payload | ConvertTo-Json -Compress $h = ConvertTo-Base64UrlEncoding $h_json $p = ConvertTo-Base64UrlEncoding $p_json $s = Get-HMACSHA256 -Message "${h}.${p}" -secret $secret "${h}.${p}.${s}" } function Get-CyClaimsFromJwtToken { Param ( [parameter(Mandatory=$true)] [String]$token ) $elems = $token.Split(".") $null = ConvertFrom-Base64UrlEncoding($elems[0]) | ConvertFrom-Json $o = ConvertFrom-Base64UrlEncoding($elems[1]) | ConvertFrom-Json $null = $elems[2] $o } |