From 618fa1f6e06c8697ea698509e77b22d3aefa9166 Mon Sep 17 00:00:00 2001
From: McSpazzy <andy@ssmvc.org>
Date: Fri, 2 Oct 2020 17:01:25 +1000
Subject: [PATCH 1/2] Add murmerhash3 support

---
 .../Security/Cryptography/mmh3.cs             | 89 +++++++++++++++++++
 Switch_Toolbox_Library/Toolbox_Library.csproj |  1 +
 Toolbox/GUI/HashCalculatorForm.cs             |  4 +
 3 files changed, 94 insertions(+)
 create mode 100644 Switch_Toolbox_Library/Security/Cryptography/mmh3.cs

diff --git a/Switch_Toolbox_Library/Security/Cryptography/mmh3.cs b/Switch_Toolbox_Library/Security/Cryptography/mmh3.cs
new file mode 100644
index 00000000..8fdfa522
--- /dev/null
+++ b/Switch_Toolbox_Library/Security/Cryptography/mmh3.cs
@@ -0,0 +1,89 @@
+using System.IO;
+using System.Text;
+
+namespace Toolbox.Library.Security.Cryptography
+{
+    public static class MurMurHash3
+    {
+        private const uint Seed = 0;
+
+        public static uint Hash(string s)
+        {
+            var ss = new MemoryStream(Encoding.UTF8.GetBytes(s));
+            return Hash(ss);
+        }
+
+        public static uint Hash(Stream stream)
+        {
+            const uint c1 = 0xcc9e2d51;
+            const uint c2 = 0x1b873593;
+
+            var h1 = Seed;
+            uint streamLength = 0;
+
+            using (var reader = new BinaryReader(stream))
+            {
+                var chunk = reader.ReadBytes(4);
+                while (chunk.Length > 0)
+                {
+                    streamLength += (uint)chunk.Length;
+                    uint k1;
+                    switch (chunk.Length)
+                    {
+                        case 4:
+                            k1 = (uint)(chunk[0] | chunk[1] << 8 | chunk[2] << 16 | chunk[3] << 24);
+                            k1 *= c1;
+                            k1 = Rot(k1, 15);
+                            k1 *= c2;
+                            h1 ^= k1;
+                            h1 = Rot(h1, 13);
+                            h1 = h1 * 5 + 0xe6546b64;
+                            break;
+                        case 3:
+                            k1 = (uint) (chunk[0] | chunk[1] << 8 | chunk[2] << 16);
+                            k1 *= c1;
+                            k1 = Rot(k1, 15);
+                            k1 *= c2;
+                            h1 ^= k1;
+                            break;
+                        case 2:
+                            k1 = (uint) (chunk[0] | chunk[1] << 8);
+                            k1 *= c1;
+                            k1 = Rot(k1, 15);
+                            k1 *= c2;
+                            h1 ^= k1;
+                            break;
+                        case 1:
+                            k1 = (chunk[0]);
+                            k1 *= c1;
+                            k1 = Rot(k1, 15);
+                            k1 *= c2;
+                            h1 ^= k1;
+                            break;
+                    }
+                    chunk = reader.ReadBytes(4);
+                }
+            }
+
+            h1 ^= streamLength;
+            h1 = Mix(h1);
+
+            return h1;
+        }
+
+        private static uint Rot(uint x, byte r)
+        {
+            return (x << r) | (x >> (32 - r));
+        }
+
+        private static uint Mix(uint h)
+        {
+            h ^= h >> 16;
+            h *= 0x85ebca6b;
+            h ^= h >> 13;
+            h *= 0xc2b2ae35;
+            h ^= h >> 16;
+            return h;
+        }
+    }
+}
diff --git a/Switch_Toolbox_Library/Toolbox_Library.csproj b/Switch_Toolbox_Library/Toolbox_Library.csproj
index 67abc8be..f3c6d3d8 100644
--- a/Switch_Toolbox_Library/Toolbox_Library.csproj
+++ b/Switch_Toolbox_Library/Toolbox_Library.csproj
@@ -450,6 +450,7 @@
     <Compile Include="Rendering\GenericModelRenderer\GenericRenderedObject.cs" />
     <Compile Include="Security\Cryptography\crc32.cs" />
     <Compile Include="DrawableContainer.cs" />
+    <Compile Include="Security\Cryptography\mmh3.cs" />
     <Compile Include="StaticDynamic.cs" />
     <Compile Include="Texture Decoding\3DS\ETC1.cs" />
     <Compile Include="FileFormats\Animation\SMD.cs" />
diff --git a/Toolbox/GUI/HashCalculatorForm.cs b/Toolbox/GUI/HashCalculatorForm.cs
index 18de22b5..67ff12b1 100644
--- a/Toolbox/GUI/HashCalculatorForm.cs
+++ b/Toolbox/GUI/HashCalculatorForm.cs
@@ -9,6 +9,7 @@ using System.Threading;
 using System.Windows.Forms;
 using Toolbox.Library.Forms;
 using Toolbox.Library;
+using Toolbox.Library.Security.Cryptography;
 
 namespace Toolbox
 {
@@ -27,6 +28,7 @@ namespace Toolbox
             hashTypeCB.Items.Add("CRC32");
             hashTypeCB.Items.Add("BCSV");
             hashTypeCB.Items.Add("SARC");
+            hashTypeCB.Items.Add("MMH3");
 
             hashTypeCB.SelectedIndex = 0;
 
@@ -71,6 +73,8 @@ namespace Toolbox
                 return stringToHash(text);
             else if (type == "SARC")
                 return NameHash(text);
+            else if (type == "MMH3")
+                return MurMurHash3.Hash(text);
             return 0;
         }
 

From 67eb77dcb62d58cd486a70e093c5ddf5d26fd8c9 Mon Sep 17 00:00:00 2001
From: McSpazzy <andy@ssmvc.org>
Date: Fri, 2 Oct 2020 17:15:24 +1000
Subject: [PATCH 2/2] Use full name instead of import

---
 Toolbox/GUI/HashCalculatorForm.cs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/Toolbox/GUI/HashCalculatorForm.cs b/Toolbox/GUI/HashCalculatorForm.cs
index 67ff12b1..2e215bba 100644
--- a/Toolbox/GUI/HashCalculatorForm.cs
+++ b/Toolbox/GUI/HashCalculatorForm.cs
@@ -9,7 +9,6 @@ using System.Threading;
 using System.Windows.Forms;
 using Toolbox.Library.Forms;
 using Toolbox.Library;
-using Toolbox.Library.Security.Cryptography;
 
 namespace Toolbox
 {
@@ -74,7 +73,7 @@ namespace Toolbox
             else if (type == "SARC")
                 return NameHash(text);
             else if (type == "MMH3")
-                return MurMurHash3.Hash(text);
+                return Toolbox.Library.Security.Cryptography.MurMurHash3.Hash(text);
             return 0;
         }