Adds Get-RandomPassword comdlet

Author: alexpilotti

Get-RandomPassword.ps1

@@ -0,0 +1,90 @@
+<#
+Copyright 2014 Cloudbase Solutions Srl
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+#>
+
+$Source = @"
+using System;
+using System.Text;
+using System.Runtime.InteropServices;
+
+namespace PSCloudbase
+{
+    public sealed class Win32CryptApi
+    {
+        public static long CRYPT_SILENT                     = 0x00000040;
+        public static long CRYPT_VERIFYCONTEXT              = 0xF0000000;
+        public static int PROV_RSA_FULL                     = 1;
+
+        [DllImport("advapi32.dll", CharSet=CharSet.Auto, SetLastError=true)]
+        [return : MarshalAs(UnmanagedType.Bool)]
+        public static extern bool CryptAcquireContext(ref IntPtr hProv,
+                                                      StringBuilder pszContainer, // Don't use string, as Powershell replaces $null with an empty string
+                                                      StringBuilder pszProvider, // Don't use string, as Powershell replaces $null with an empty string
+                                                      uint dwProvType,
+                                                      uint dwFlags);
+
+        [DllImport("Advapi32.dll", EntryPoint = "CryptReleaseContext", CharSet = CharSet.Unicode, SetLastError = true)]
+        public static extern bool CryptReleaseContext(IntPtr hProv, Int32 dwFlags);
+
+        [DllImport("advapi32.dll", SetLastError=true)]
+        public static extern bool CryptGenRandom(IntPtr hProv, uint dwLen, byte[] pbBuffer);
+
+        [DllImport("Kernel32.dll")]
+        public static extern uint GetLastError();
+    }
+}
+"@
+
+Add-Type -TypeDefinition $Source -Language CSharp
+
+function Get-RandomPassword
+{
+    [CmdletBinding()]
+    param
+    (
+        [parameter(Mandatory=$true)]
+        [int]$Length
+    )
+    process
+    {
+        $hProvider = 0
+        try
+        {
+            if(![PSCloudbase.Win32CryptApi]::CryptAcquireContext([ref]$hProvider, $null, $null,
+                                                                 [PSCloudbase.Win32CryptApi]::PROV_RSA_FULL,
+                                                                 ([PSCloudbase.Win32CryptApi]::CRYPT_VERIFYCONTEXT -bor
+                                                                  [PSCloudbase.Win32CryptApi]::CRYPT_SILENT)))
+            {
+                throw "CryptAcquireContext failed with error: 0x" + "{0:X0}" -f [PSCloudbase.Win32CryptApi]::GetLastError()
+            }
+
+            $buffer = New-Object byte[] $Length
+            if(![PSCloudbase.Win32CryptApi]::CryptGenRandom($hProvider, $Length, $buffer))
+            {
+                throw "CryptGenRandom failed with error: 0x" + "{0:X0}" -f [PSCloudbase.Win32CryptApi]::GetLastError()
+            }
+
+            $buffer | ForEach-Object { $password += "{0:X0}" -f $_ }
+            return $password
+        }
+        finally
+        {
+            if($hProvider)
+            {
+                $retVal = [PSCloudbase.Win32CryptApi]::CryptReleaseContext($hProvider, 0)
+            }
+        }
+    }
+}