mcs/class/corlib/Test/System.Security.Cryptography/RandomNumberGeneratorTest.cs

   1 //
   2 // RandomNumberGeneratorTest.cs - NUnit Test Cases for RNG
   3 //
   4 // Author:
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // (C) 2002 Motus Technologies Inc. (http://www.motus.com)
   8 // Copyright (C) 2006 Novell, Inc (http://www.novell.com)
   9 //
  10
  11 using NUnit.Framework;
  12 using System;
  13 using System.IO;
  14 using System.Security.Cryptography;
  15 using System.Text;
  16
  17 namespace MonoTests.System.Security.Cryptography {
  18
  19 // References:
  20 // a.   NIST FIPS PUB 140-2: Security requirements for Cryptographic Modules
  21 //      http://csrc.nist.gov/publications/fips/fips140-2/fips1402.pdf
  22 // b.   NIST SP 800-22: A Statistical Test Suite for Random and Pseudorandom Number Generators for Cryptographic Applications
  23 //      not implemented
  24 //      http://csrc.nist.gov/publications/nistpubs/800-22/sp-800-22-051501.pdf
  25 // c.   IETF RFC1750: Randomness Recommendations for Security
  26 //      not implemented
  27 //      http://www.ietf.org/rfc/rfc1750.txt
  28
  29 [TestFixture]
  30 public class RandomNumberGeneratorTest {
  31
  32         private string name;
  33         private byte[] sample;
  34
  35         [TestFixtureSetUp]
  36         public void SetUp ()
  37         {
  38                 // all tests should be done on the same random sample
  39                 RandomNumberGenerator rng = RandomNumberGenerator.Create ();
  40                 name = rng.ToString ();
  41                 // 20,000 bits
  42                 sample = new byte[2500];
  43                 rng.GetBytes (sample);
  44         }
  45
  46         // count the number of 1
  47         [Test]
  48         public void Monobit ()
  49         {
  50                 int x = 0;
  51                 for (int i=0; i < sample.Length; i++) {
  52                         byte b = sample[i];
  53                         for (int j = 0; j < 8; j++) {
  54                                 if ((b & 0x01) == 0x01)
  55                                         x++;
  56                                 // next bit
  57                                 b >>= 1;
  58                         }
  59                 }
  60                 Assert.IsTrue ((9725  < x), String.Format ("{0} Monobit x={1} > 9725",  name, x));
  61                 Assert.IsTrue ((x < 10275), String.Format ("{0} Monobit x={1} < 10275", name, x));
  62         }
  63
  64         // 16 patterns (nibbles)
  65         [Test]
  66         public void Poker ()
  67         {
  68                 int[] pattern = new int[16];
  69                 for (int i = 0; i < sample.Length; i++) {
  70                         byte b = sample[i];
  71                         int n = (b & 0x0F);
  72                         pattern[n]++;
  73                         b >>= 4;
  74                         n = b;
  75                         pattern[n]++;
  76                 }
  77                 double result = 0;
  78                 for (int i = 0; i < 16; i++)
  79                         result += (pattern[i] * pattern[i]);
  80                 result = ((16 * result) / 5000) - 5000;
  81
  82                 Assert.IsTrue (((result > 2.16) && (result < 46.17)), name + " Poker: " + result);
  83         }
  84
  85         // runs of 1 (or 0)
  86         [Test]
  87         public void Runs ()
  88         {
  89                 int[,] runs = new int[6,2];
  90                 int x = 0;
  91                 bool one = false;
  92                 bool zero = false;
  93                 for (int i = sample.Length - 1; i >= 0 ; i--) {
  94                         byte b = sample[i];
  95                         for (int j = 0; j < 8; j++) {
  96                                 if ((b & 0x01) == 0x01) {
  97                                         if (!one) {
  98                                                 one = true;
  99                                                 zero = false;
 100                                                 int p = Math.Min (x, 6) - 1;
 101                                                 if (p >= 0)
 102                                                         runs[p,0]++;
 103                                                 x = 0;
 104                                         }
 105                                 }
 106                                 else {
 107                                         if (!zero) {
 108                                                 one = false;
 109                                                 zero = true;
 110                                                 int p = Math.Min (x, 6) - 1;
 111                                                 if (p >= 0)
 112                                                         runs[p,1]++;
 113                                                 x = 0;
 114                                         }
 115                                 }
 116                                 x++;
 117                                 // next bit
 118                                 b >>= 1;
 119                         }
 120                 }
 121                 // don't forget the ast run
 122                 if (x > 0) {
 123                         int p = Math.Min (x, 6) - 1;
 124                         if (p >= 0)
 125                                 runs [p, zero ? 0 : 1]++;
 126                 }
 127                 // Updated ranges as per FIPS140-2 Change Notice #1
 128                 // check for runs of zeros
 129                 Assert.IsTrue (((runs[0,0] >= 2315) && (runs[0,0] <= 2685)), name + " 0-Runs length=1: " + runs[0,0]);
 130                 Assert.IsTrue (((runs[1,0] >= 1114) && (runs[1,0] <= 1386)), name + " 0-Runs length=2: " + runs[1,0]);
 131                 Assert.IsTrue (((runs[2,0] >=  527) && (runs[2,0] <=  723)), name + " 0-Runs length=3: " + runs[2,0]);
 132                 Assert.IsTrue (((runs[3,0] >=  240) && (runs[3,0] <=  384)), name + " 0-Runs length=4: " + runs[3,0]);
 133                 Assert.IsTrue (((runs[4,0] >=  103) && (runs[4,0] <=  209)), name + " 0-Runs length=5: " + runs[4,0]);
 134                 Assert.IsTrue (((runs[5,0] >=  103) && (runs[5,0] <=  209)), name + " 0-Runs length=6+ " + runs[5,0]);
 135                 // check for runs of ones
 136                 Assert.IsTrue (((runs[0,1] >= 2315) && (runs[0,1] <= 2685)), name + " 1-Runs length=1: " + runs[0,1]);
 137                 Assert.IsTrue (((runs[1,1] >= 1114) && (runs[1,1] <= 1386)), name + " 1-Runs length=2: " + runs[1,1]);
 138                 Assert.IsTrue (((runs[2,1] >=  527) && (runs[2,1] <=  723)), name + " 1-Runs length=3: " + runs[2,1]);
 139                 Assert.IsTrue (((runs[3,1] >=  240) && (runs[3,1] <=  384)), name + " 1-Runs length=4: " + runs[3,1]);
 140                 Assert.IsTrue (((runs[4,1] >=  103) && (runs[4,1] <=  209)), name + " 1-Runs length=5: " + runs[4,1]);
 141                 Assert.IsTrue (((runs[5,1] >=  103) && (runs[5,1] <=  209)), name + " 1-Runs length=6+ " + runs[5,1]);
 142         }
 143
 144         // no long runs of 26 or more (0 or 1)
 145         [Test]
 146         public void LongRuns ()
 147         {
 148                 int longestRun = 0;
 149                 int currentRun = 0;
 150                 bool one = false;
 151                 bool zero = false;
 152                 for (int i = sample.Length - 1; i >= 0 ; i--) {
 153                         byte b = sample[i];
 154                         for (int j = 0; j < 8; j++) {
 155                                 if ((b & 0x01) == 0x01) {
 156                                         if (!one) {
 157                                                 one = true;
 158                                                 zero = false;
 159                                                 longestRun = Math.Max (longestRun, currentRun);
 160                                                 currentRun = 0;
 161                                         }
 162                                         currentRun++;
 163                                 }
 164                                 else {
 165                                         if (!zero) {
 166                                                 one = false;
 167                                                 zero = true;
 168                                                 longestRun = Math.Max (longestRun, currentRun);
 169                                                 currentRun = 0;
 170                                         }
 171                                         currentRun++;
 172                                 }
 173                                 // next bit
 174                                 b >>= 1;
 175                         }
 176                 }
 177                 Assert.IsTrue ((longestRun < 26), name + " Long Runs max = " + longestRun);
 178         }
 179 }
 180
 181 }