mcs/class/Mono.Security.Win32/Mono.Security.Cryptography/CapiContext.cs

   1 //
   2 // Mono.Security.Cryptography.CapiContext
   3 //
   4 // Authors:
   5 //      Sebastien Pouliot (sebastien@ximian.com)
   6 //
   7 // Copyright (C) 2003 Motus Technologies Inc. (http://www.motus.com)
   8 // Copyright (C) 2004 Novell (http://www.novell.com)
   9 //
  10
  11 using System;
  12 using System.Security.Cryptography;
  13
  14 namespace Mono.Security.Cryptography {
  15
  16 // we deal with unmanaged resources - they MUST be released after use!
  17 public class CapiContext : IDisposable {
  18
  19         // handles to CryptoAPI - they are
  20         private IntPtr providerHandle;
  21
  22         private CspParameters cspParams;
  23
  24         // has the last call succeded ?
  25         private bool lastResult;
  26
  27         // Create an instance using the default CSP
  28         public CapiContext () : this (null)
  29         {
  30         }
  31
  32         // Create an instance using the specified CSP
  33         public CapiContext (CspParameters csp)
  34         {
  35                 providerHandle = IntPtr.Zero;
  36                 if (csp == null) {
  37                         // default parameters
  38                         cspParams = new CspParameters ();
  39                 }
  40                 else {
  41                         // keep of copy of the parameters
  42                         cspParams = new CspParameters (csp.ProviderType, csp.ProviderName, csp.KeyContainerName);
  43                         cspParams.KeyNumber = csp.KeyNumber;
  44                         cspParams.Flags = csp.Flags;
  45                 }
  46
  47                 // do not show user interface (CRYPT_SILENT) -  if UI is required then the function fails.
  48                 uint flags = CryptoAPI.CRYPT_SILENT;
  49                 if ((cspParams.Flags & CspProviderFlags.UseMachineKeyStore) == CspProviderFlags.UseMachineKeyStore) {
  50                         flags |= CryptoAPI.CRYPT_MACHINE_KEYSET;
  51                 }
  52
  53                 lastResult = CryptoAPI.CryptAcquireContextA (ref providerHandle, cspParams.KeyContainerName,
  54                         cspParams.ProviderName, cspParams.ProviderType, flags);
  55                 if (!lastResult) {
  56                         // key container may not exist
  57                         flags |= CryptoAPI.CRYPT_NEWKEYSET;
  58                         lastResult = CryptoAPI.CryptAcquireContextA (ref providerHandle, cspParams.KeyContainerName,
  59                                 cspParams.ProviderName, cspParams.ProviderType, flags);
  60                 }
  61         }
  62
  63         ~CapiContext ()
  64         {
  65                 Dispose ();
  66         }
  67
  68         public int Error {
  69                 get { return CryptoAPI.GetLastError (); }
  70         }
  71
  72         public IntPtr Handle {
  73                 get { return providerHandle; }
  74         }
  75
  76         public bool Result {
  77                 get { return lastResult; }
  78         }
  79
  80         internal bool InternalResult {
  81                 set { lastResult = value; }
  82         }
  83
  84         // release unmanaged resources
  85         public void Dispose ()
  86         {
  87                 if (providerHandle != IntPtr.Zero) {
  88                         lastResult = CryptoAPI.CryptReleaseContext (providerHandle, 0);
  89                         GC.KeepAlive (this);
  90                         providerHandle = IntPtr.Zero;
  91                         GC.SuppressFinalize (this);
  92                 }
  93         }
  94 }
  95
  96 }