Fixed IPv4 detection of TCP

Author: Noah Potash

Diff for: src/LibPacketGremlin/LibPacketGremlin.csproj

@@ -14,9 +14,9 @@
     <PackageProjectUrl>https://github.com/SapientGuardian/LibPacketGremlin</PackageProjectUrl>
     <PackageLicenseUrl>http://opensource.org/licenses/MIT</PackageLicenseUrl>
     <PackageTargetFallback>$(PackageTargetFallback);dnxcore50</PackageTargetFallback>
-    <Version>1.0.1</Version>
-    <AssemblyVersion>0.1.0.1</AssemblyVersion>
-    <FileVersion>0.1.0.1</FileVersion>
+    <Version>1.0.2</Version>
+    <AssemblyVersion>0.1.0.2</AssemblyVersion>
+    <FileVersion>0.1.0.2</FileVersion>
   </PropertyGroup>
 
   <ItemGroup>

Diff for: src/LibPacketGremlin/Packets/IPv4.cs

@@ -235,7 +235,7 @@ public void CorrectFields()
             this.HeaderLength = 5 + this.OptionsAndPadding.Length / 4;
             this.TotalLength = (ushort)(this.HeaderLength * 4 + this.Payload.Length());
 
-            // TODO: Add TCP when ported over
+            
             if (this.Payload is IPv4)
             {
                 this.Protocol = (byte)Protocols.IP;
@@ -248,6 +248,10 @@ public void CorrectFields()
             {
                 this.Protocol = (byte)Protocols.ICMP;
             }
+            else if (this.Payload is TCP)
+            {
+                this.Protocol = (byte)Protocols.TCP;
+            }
 
             this.HeaderChecksum = 0;
             this.HeaderChecksum = ComputeChecksum(this.ToArray(), 0, this.HeaderLength * 4);
@@ -382,7 +386,19 @@ internal static bool TryParse(byte[] buffer, int index, int count, out IPv4 pack
                                 }
 
                                 break;
-                            // TODO: Add TCP when ported over
+                            case (byte)Protocols.TCP:
+                                {
+                                    TCP payload;
+                                    if (TCP.TryParse(
+                                        buffer,
+                                        index + (int)br.BaseStream.Position,
+                                        payloadLength,
+                                        out payload))
+                                    {
+                                        packet = new IPv4<TCP> { Payload = payload };
+                                    }
+                                }
+                                break;
                         }
 
                         if (packet == null)

Diff for: test/LibPacketGremlinTests/LibPacketGremlinTests.csproj

@@ -31,6 +31,9 @@
   </ItemGroup>
 
   <ItemGroup>
+    <None Update="Resources\msmon80211tcp.bin">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
     <None Update="Resources\radiotap.bin">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </None>

Diff for: test/LibPacketGremlinTests/Packets/IPv4Tests.cs

@@ -11,6 +11,9 @@
     using Xunit;
     using OutbreakLabs.LibPacketGremlin.PacketFactories;
     using OutbreakLabs.LibPacketGremlin.Extensions;
+    using OutbreakLabs.LibPacketGremlin.Abstractions;
+    using OutbreakLabs.LibPacketGremlin.Utilities;
+
     public class IPv4Tests
     {
         [Fact]
@@ -43,7 +46,7 @@ public void ParsesBasicFields()
             packet.HeaderChecksum.Should().Be(46798);
             packet.SourceAddress.Should().Be(IPv4Address.Parse("192.168.1.3"));
             packet.DestAddress.Should().Be(IPv4Address.Parse("192.168.1.123"));
-            
+
         }
 
         [Fact]
@@ -58,7 +61,7 @@ public void SerializesCorrectly()
             0x9f, 0xd8, 0xb7, 0xc4, 0xc5, 0xa6, 0x07, 0x36, 0xca, 0xce, 0x11, 0x3b,
             0x32, 0xcd, 0x87, 0x1c, 0x24, 0x2d, 0xad, 0x15, 0xc4, 0x0f}, out packet).Should().BeTrue();
 
-            
+
             using (var ms = new MemoryStream())
             {
                 packet.WriteToStream(ms);
@@ -118,5 +121,16 @@ public void CalculatesLength()
             packet.Length().Should().Be(packet.ToArray().Length);
 
         }
+
+        [Fact]
+        public void ChainsToTCP()
+        {
+            byte[] rawBytes = System.IO.File.ReadAllBytes(Path.Combine("Resources", "msmon80211tcp.bin"));
+            IPacket encryptedPacket;
+            var parsed = MSMon802_11Factory.Instance.TryParse(rawBytes, out encryptedPacket);
+            IPacket decrypted;
+            IEEE802_11Crypto.TryDecryptWEP(encryptedPacket.Layer<IEEE802_11>(), new byte[] { 0xC5, 0x8D, 0xB1, 0x5E, 0x2B }, out decrypted);
+            decrypted.Layer<TCP>().Should().NotBeNull();
+        }
     }
 }