mcs/class/referencesource/mscorlib/system/security/cryptography/rngcryptoserviceprovider.cs

   1 // ==++==
   2 //
   3 //   Copyright (c) Microsoft Corporation.  All rights reserved.
   4 //
   5 // ==--==
   6 // <OWNER>Microsoft</OWNER>
   7 //
   8
   9 //
  10 // RNGCryptoServiceProvider.cs
  11 //
  12
  13 namespace System.Security.Cryptography {
  14     using Microsoft.Win32;
  15     using System.Runtime.CompilerServices;
  16     using System.Runtime.InteropServices;
  17     using System.Security;
  18     using System.Runtime.Versioning;
  19     using System.Diagnostics.Contracts;
  20
  21 #if !FEATURE_CORECLR
  22 [System.Runtime.InteropServices.ComVisible(true)]
  23 #endif // !FEATURE_CORECLR
  24     public sealed class RNGCryptoServiceProvider : RandomNumberGenerator {
  25 #if !FEATURE_CORECLR
  26         [System.Security.SecurityCritical] // auto-generated
  27         SafeProvHandle m_safeProvHandle;
  28         bool m_ownsHandle;
  29 #else // !FEATURE_CORECLR
  30         #if FEATURE_CORECLR
  31         [System.Security.SecurityCritical] // auto-generated
  32         #endif
  33         SafeCspHandle m_cspHandle;
  34 #endif // !FEATURE_CORECLR
  35
  36         //
  37         // public constructors
  38         //
  39
  40 #if !FEATURE_CORECLR
  41
  42 #if !FEATURE_PAL
  43         public RNGCryptoServiceProvider() : this((CspParameters) null) {}
  44 #else // !FEATURE_PAL
  45         public RNGCryptoServiceProvider() { }
  46 #endif // !FEATURE_PAL
  47
  48 #if !FEATURE_PAL
  49         public RNGCryptoServiceProvider(string str) : this((CspParameters) null) {}
  50
  51         public RNGCryptoServiceProvider(byte[] rgb) : this((CspParameters) null) {}
  52
  53         [System.Security.SecuritySafeCritical]  // auto-generated
  54         public RNGCryptoServiceProvider(CspParameters cspParams) {
  55             if (cspParams != null) {
  56                 m_safeProvHandle = Utils.AcquireProvHandle(cspParams);
  57                 m_ownsHandle = true;
  58             }
  59             else {
  60                 m_safeProvHandle = Utils.StaticProvHandle;
  61                 m_ownsHandle = false;
  62             }
  63         }
  64
  65         [System.Security.SecuritySafeCritical]  // auto-generated
  66         protected override void Dispose(bool disposing) {
  67             base.Dispose(disposing);
  68
  69             if (disposing && m_ownsHandle) {
  70                 m_safeProvHandle.Dispose();
  71             }
  72         }
  73 #endif // !FEATURE_PAL
  74
  75 #else // !FEATURE_CORECLR
  76
  77         #if FEATURE_CORECLR
  78         [System.Security.SecuritySafeCritical] // auto-generated
  79         #endif
  80         public RNGCryptoServiceProvider() {
  81             m_cspHandle = CapiNative.AcquireCsp(null,
  82                                                 CapiNative.ProviderNames.MicrosoftEnhanced,
  83                                                 CapiNative.ProviderType.RsaFull,
  84                                                 CapiNative.CryptAcquireContextFlags.VerifyContext);
  85         }
  86 #endif // !FEATURE_CORECLR
  87
  88         //
  89         // public methods
  90         //
  91 #if !FEATURE_CORECLR
  92         [System.Security.SecuritySafeCritical]  // auto-generated
  93         public override void GetBytes(byte[] data) {
  94             if (data == null) throw new ArgumentNullException("data");
  95             Contract.EndContractBlock();
  96 #if !FEATURE_PAL
  97             GetBytes(m_safeProvHandle, data, data.Length);
  98 #else
  99             if (!Win32Native.Random(true, data, data.Length))
 100                 throw new CryptographicException(Marshal.GetLastWin32Error());
 101 #endif // !FEATURE_PAL
 102         }
 103
 104         [System.Security.SecuritySafeCritical]  // auto-generated
 105         public override void GetNonZeroBytes(byte[] data) {
 106             if (data == null)
 107                 throw new ArgumentNullException("data");
 108             Contract.EndContractBlock();
 109
 110 #if !FEATURE_PAL
 111             GetNonZeroBytes(m_safeProvHandle, data, data.Length);
 112 #else
 113             GetBytes(data);
 114
 115             int indexOfFirst0Byte = data.Length;
 116             for (int i = 0; i < data.Length; i++) {
 117                 if (data[i] == 0) {
 118                     indexOfFirst0Byte = i;
 119                     break;
 120                 }
 121             }
 122             for (int i = indexOfFirst0Byte; i < data.Length; i++) {
 123                 if (data[i] != 0) {
 124                     data[indexOfFirst0Byte++] = data[i];
 125                 }
 126             }
 127
 128             while (indexOfFirst0Byte < data.Length) {
 129                 // this should be more than enough to fill the rest in one iteration
 130                 byte[] tmp = new byte[2 * (data.Length - indexOfFirst0Byte)];
 131                 GetBytes(tmp);
 132
 133                 for (int i = 0; i < tmp.Length; i++) {
 134                     if (tmp[i] != 0) {
 135                         data[indexOfFirst0Byte++] = tmp[i];
 136                         if (indexOfFirst0Byte >= data.Length) break;
 137                     }
 138                 }
 139             }
 140 #endif // !FEATURE_PAL
 141         }
 142
 143 #else // !FEATURE_CORECLR
 144
 145         #if FEATURE_CORECLR
 146         [System.Security.SecuritySafeCritical] // auto-generated
 147         #endif
 148         protected override void Dispose(bool disposing) {
 149             try {
 150                 if (disposing) {
 151                     if (m_cspHandle != null) {
 152                         m_cspHandle.Dispose();
 153                     }
 154                 }
 155             }
 156             finally {
 157                 base.Dispose(disposing);
 158             }
 159         }
 160
 161         #if FEATURE_CORECLR
 162         [System.Security.SecuritySafeCritical] // auto-generated
 163         #endif
 164         public override void GetBytes(byte[] data) {
 165             if (data == null) {
 166                 throw new ArgumentNullException("data");
 167             }
 168             Contract.EndContractBlock();
 169
 170             if (data.Length > 0) {
 171                 CapiNative.GenerateRandomBytes(m_cspHandle, data);
 172             }
 173         }
 174
 175         #if FEATURE_CORECLR
 176         [System.Security.SecuritySafeCritical] // auto-generated
 177         #endif
 178         public override void GetBytes(byte[] data, int offset, int count) {
 179             if (data == null) throw new ArgumentNullException("data");
 180             if (offset < 0) throw new ArgumentOutOfRangeException("offset", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
 181             if (count < 0) throw new ArgumentOutOfRangeException("count", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
 182             if (offset + count > data.Length) throw new ArgumentException(Environment.GetResourceString("Argument_InvalidOffLen"));
 183
 184             if (count > 0) {
 185                 CapiNative.GenerateRandomBytes(m_cspHandle, data, offset, count);
 186             }
 187         }
 188 #endif // !FEATURE_CORECLR
 189
 190 #if !FEATURE_PAL
 191         [System.Security.SecurityCritical]  // auto-generated
 192         [DllImport(JitHelpers.QCall, CharSet = CharSet.Unicode), SuppressUnmanagedCodeSecurity]
 193         [ResourceExposure(ResourceScope.None)]
 194         private static extern void GetBytes(SafeProvHandle hProv, byte[] randomBytes, int count);
 195
 196         [System.Security.SecurityCritical]  // auto-generated
 197         [DllImport(JitHelpers.QCall, CharSet = CharSet.Unicode), SuppressUnmanagedCodeSecurity]
 198         [ResourceExposure(ResourceScope.None)]
 199         private static extern void GetNonZeroBytes(SafeProvHandle hProv, byte[] randomBytes, int count);
 200 #endif
 201     }
 202 }