├── .gitignore ├── FileTypeChecker.Tests ├── FileTypeChecker.Tests.csproj ├── FileTypeCheckerTests.cs ├── Properties │ ├── AssemblyInfo.cs │ ├── Resources.Designer.cs │ └── Resources.resx ├── Resources │ ├── LAND.BMP │ └── advancedquantumthermodynamics.pdf └── packages.config ├── FileTypeChecker.sln ├── FileTypeChecker ├── App.config ├── ExactFileTypeMatcher.cs ├── FileType.cs ├── FileTypeChecker.cs ├── FileTypeChecker.csproj ├── FileTypeChecker.nuspec ├── FileTypeMatcher.cs ├── FuzzyFileTypeMatcher.cs ├── IFileTypeChecker.cs ├── Properties │ └── AssemblyInfo.cs └── RangeFileTypeMatcher.cs ├── LICENSE.md └── README.md /.gitignore: -------------------------------------------------------------------------------- 1 | ## Ignore Visual Studio temporary files, build results, and 2 | ## files generated by popular Visual Studio add-ons. 3 | 4 | # User-specific files 5 | *.suo 6 | *.user 7 | *.userosscache 8 | *.sln.docstates 9 | 10 | # User-specific files (MonoDevelop/Xamarin Studio) 11 | *.userprefs 12 | 13 | # Build results 14 | [Dd]ebug/ 15 | [Dd]ebugPublic/ 16 | [Rr]elease/ 17 | [Rr]eleases/ 18 | x64/ 19 | x86/ 20 | build/ 21 | bld/ 22 | [Bb]in/ 23 | [Oo]bj/ 24 | 25 | # Visual Studo 2015 cache/options directory 26 | .vs/ 27 | 28 | # MSTest test Results 29 | [Tt]est[Rr]esult*/ 30 | [Bb]uild[Ll]og.* 31 | 32 | # NUNIT 33 | *.VisualState.xml 34 | TestResult.xml 35 | 36 | # Build Results of an ATL Project 37 | [Dd]ebugPS/ 38 | [Rr]eleasePS/ 39 | dlldata.c 40 | 41 | *_i.c 42 | *_p.c 43 | *_i.h 44 | *.ilk 45 | *.meta 46 | *.obj 47 | *.pch 48 | *.pdb 49 | *.pgc 50 | *.pgd 51 | *.rsp 52 | *.sbr 53 | *.tlb 54 | *.tli 55 | *.tlh 56 | *.tmp 57 | *.tmp_proj 58 | *.log 59 | *.vspscc 60 | *.vssscc 61 | .builds 62 | *.pidb 63 | *.svclog 64 | *.scc 65 | 66 | # Chutzpah Test files 67 | _Chutzpah* 68 | 69 | # Visual C++ cache files 70 | ipch/ 71 | *.aps 72 | *.ncb 73 | *.opensdf 74 | *.sdf 75 | *.cachefile 76 | 77 | # Visual Studio profiler 78 | *.psess 79 | *.vsp 80 | *.vspx 81 | 82 | # TFS 2012 Local Workspace 83 | $tf/ 84 | 85 | # Guidance Automation Toolkit 86 | *.gpState 87 | 88 | # ReSharper is a .NET coding add-in 89 | _ReSharper*/ 90 | *.[Rr]e[Ss]harper 91 | *.DotSettings.user 92 | 93 | # JustCode is a .NET coding addin-in 94 | .JustCode 95 | 96 | # TeamCity is a build add-in 97 | _TeamCity* 98 | 99 | # DotCover is a Code Coverage Tool 100 | *.dotCover 101 | 102 | # NCrunch 103 | _NCrunch_* 104 | .*crunch*.local.xml 105 | 106 | # MightyMoose 107 | *.mm.* 108 | AutoTest.Net/ 109 | 110 | # Web workbench (sass) 111 | .sass-cache/ 112 | 113 | # Installshield output folder 114 | [Ee]xpress/ 115 | 116 | # DocProject is a documentation generator add-in 117 | DocProject/buildhelp/ 118 | DocProject/Help/*.HxT 119 | DocProject/Help/*.HxC 120 | DocProject/Help/*.hhc 121 | DocProject/Help/*.hhk 122 | DocProject/Help/*.hhp 123 | DocProject/Help/Html2 124 | DocProject/Help/html 125 | 126 | # Click-Once directory 127 | publish/ 128 | 129 | # Publish Web Output 130 | *.[Pp]ublish.xml 131 | *.azurePubxml 132 | # TODO: Comment the next line if you want to checkin your web deploy settings 133 | # but database connection strings (with potential passwords) will be unencrypted 134 | *.pubxml 135 | *.publishproj 136 | 137 | # NuGet Packages 138 | *.nupkg 139 | # The packages folder can be ignored because of Package Restore 140 | **/packages/* 141 | # except build/, which is used as an MSBuild target. 142 | !**/packages/build/ 143 | # Uncomment if necessary however generally it will be regenerated when needed 144 | #!**/packages/repositories.config 145 | 146 | # Windows Azure Build Output 147 | csx/ 148 | *.build.csdef 149 | 150 | # Windows Store app package directory 151 | AppPackages/ 152 | 153 | # Others 154 | *.[Cc]ache 155 | ClientBin/ 156 | [Ss]tyle[Cc]op.* 157 | ~$* 158 | *~ 159 | *.dbmdl 160 | *.dbproj.schemaview 161 | *.pfx 162 | *.publishsettings 163 | node_modules/ 164 | bower_components/ 165 | 166 | # RIA/Silverlight projects 167 | Generated_Code/ 168 | 169 | # Backup & report files from converting an old project file 170 | # to a newer Visual Studio version. Backup files are not needed, 171 | # because we have git ;-) 172 | _UpgradeReport_Files/ 173 | Backup*/ 174 | UpgradeLog*.XML 175 | UpgradeLog*.htm 176 | 177 | # SQL Server files 178 | *.mdf 179 | *.ldf 180 | 181 | # Business Intelligence projects 182 | *.rdl.data 183 | *.bim.layout 184 | *.bim_*.settings 185 | 186 | # Microsoft Fakes 187 | FakesAssemblies/ 188 | 189 | # Node.js Tools for Visual Studio 190 | .ntvs_analysis.dat 191 | 192 | # Visual Studio 6 build log 193 | *.plg 194 | 195 | # Visual Studio 6 workspace options file 196 | *.opt 197 | -------------------------------------------------------------------------------- /FileTypeChecker.Tests/FileTypeChecker.Tests.csproj: -------------------------------------------------------------------------------- 1 |  2 | 3 | 4 | 5 | Debug 6 | AnyCPU 7 | {716D0AB2-5088-4A22-A6E8-24B8D2F2039B} 8 | Library 9 | Properties 10 | FileTypeChecker.Tests 11 | FileTypeChecker.Tests 12 | v4.5 13 | 512 14 | 15 | 16 | true 17 | full 18 | false 19 | bin\Debug\ 20 | DEBUG;TRACE 21 | prompt 22 | 4 23 | 24 | 25 | pdbonly 26 | true 27 | bin\Release\ 28 | TRACE 29 | prompt 30 | 4 31 | 32 | 33 | 34 | ..\packages\NUnit.2.6.4\lib\nunit.framework.dll 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | True 50 | True 51 | Resources.resx 52 | 53 | 54 | 55 | 56 | {0ae201d3-ce5b-404f-8c25-36bd929e1d19} 57 | FileTypeChecker 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 | ResXFileCodeGenerator 67 | Resources.Designer.cs 68 | 69 | 70 | 71 | 72 | 73 | 74 | 81 | -------------------------------------------------------------------------------- /FileTypeChecker.Tests/FileTypeCheckerTests.cs: -------------------------------------------------------------------------------- 1 | namespace FileTypeChecker.Tests 2 | { 3 | using System.Drawing.Imaging; 4 | using System.IO; 5 | using System.Linq; 6 | using System.Collections.Generic; 7 | using NUnit.Framework; 8 | 9 | using Properties; 10 | 11 | [TestFixture] 12 | public class FileTypeCheckerTests 13 | { 14 | [TestFixture] 15 | public class WhenTheFileIsKnown 16 | { 17 | private MemoryStream bitmap; 18 | 19 | private MemoryStream pdf; 20 | 21 | private FileTypeChecker checker; 22 | 23 | [TestFixtureSetUp] 24 | public void SetUp() 25 | { 26 | bitmap = new MemoryStream(); 27 | // LAND.bmp is from http://www.fileformat.info/format/bmp/sample/ 28 | Resources.LAND.Save(bitmap, ImageFormat.Bmp); 29 | // http://boingboing.net/2015/03/23/free-pdf-advanced-quantum-the.html 30 | pdf = new MemoryStream(Resources.advancedquantumthermodynamics); 31 | checker = new FileTypeChecker(); 32 | } 33 | 34 | [Test] 35 | public void ItDetectsPDFs() 36 | { 37 | var fileTypes = checker.GetFileTypes(pdf); 38 | CollectionAssert.AreEquivalent( 39 | new[] { "Portable Document Format" }, 40 | fileTypes.Select(fileType => fileType.Name)); 41 | } 42 | 43 | [Test] 44 | public void ItDetectsBMPs() 45 | { 46 | var fileTypes = checker.GetFileTypes(bitmap); 47 | CollectionAssert.AreEquivalent( 48 | new[] { "Bitmap" }, 49 | fileTypes.Select(fileType => fileType.Name)); 50 | } 51 | } 52 | 53 | [TestFixture] 54 | public class WhenTheFileIsUnknown 55 | { 56 | private MemoryStream bitmap; 57 | 58 | private MemoryStream pdf; 59 | 60 | private FileTypeChecker checker; 61 | 62 | [TestFixtureSetUp] 63 | public void SetUp() 64 | { 65 | bitmap = new MemoryStream(); 66 | // LAND.bmp is from http://www.fileformat.info/format/bmp/sample/ 67 | Resources.LAND.Save(bitmap, ImageFormat.Bmp); 68 | // http://boingboing.net/2015/03/23/free-pdf-advanced-quantum-the.html 69 | pdf = new MemoryStream(Resources.advancedquantumthermodynamics); 70 | } 71 | 72 | [Test] 73 | public void ItDoesntDetectPDFs() 74 | { 75 | checker = new FileTypeChecker(new List 76 | { 77 | new FileType("Bitmap", ".bmp", new ExactFileTypeMatcher(new byte[] {0x42, 0x4d})), 78 | new FileType("Portable Network Graphic", ".png", 79 | new ExactFileTypeMatcher(new byte[] {0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A})), 80 | new FileType("JPEG", ".jpg", 81 | new FuzzyFileTypeMatcher(new byte?[] {0xFF, 0xD, 0xFF, 0xE0, null, null, 0x4A, 0x46, 0x49, 0x46, 0x00})), 82 | new FileType("Graphics Interchange Format 87a", ".gif", 83 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x37, 0x61})), 84 | new FileType("Graphics Interchange Format 89a", ".gif", 85 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x39, 0x61})) 86 | // ... Potentially more in future 87 | }); 88 | var fileType = checker.GetFileType(pdf); 89 | Assert.AreEqual( 90 | "unknown", 91 | fileType.Name); 92 | } 93 | 94 | [Test] 95 | public void ItDoesntDetectBMPs() 96 | { 97 | checker = new FileTypeChecker(new List 98 | { 99 | new FileType("Portable Network Graphic", ".png", 100 | new ExactFileTypeMatcher(new byte[] {0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A})), 101 | new FileType("JPEG", ".jpg", 102 | new FuzzyFileTypeMatcher(new byte?[] {0xFF, 0xD, 0xFF, 0xE0, null, null, 0x4A, 0x46, 0x49, 0x46, 0x00})), 103 | new FileType("Graphics Interchange Format 87a", ".gif", 104 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x37, 0x61})), 105 | new FileType("Graphics Interchange Format 89a", ".gif", 106 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x39, 0x61})), 107 | new FileType("Portable Document Format", ".pdf", new RangeFileTypeMatcher(new ExactFileTypeMatcher(new byte[] { 0x25, 0x50, 0x44, 0x46 }), 1019)) 108 | // ... Potentially more in future 109 | }); 110 | var fileType = checker.GetFileType(bitmap); 111 | Assert.AreEqual( 112 | "unknown", 113 | fileType.Name); 114 | } 115 | 116 | } 117 | 118 | [TestFixture] 119 | public class WhenTheFileIsUnknownList 120 | { 121 | private MemoryStream bitmap; 122 | 123 | private MemoryStream pdf; 124 | 125 | private FileTypeChecker checker; 126 | 127 | [TestFixtureSetUp] 128 | public void SetUp() 129 | { 130 | bitmap = new MemoryStream(); 131 | // LAND.bmp is from http://www.fileformat.info/format/bmp/sample/ 132 | Resources.LAND.Save(bitmap, ImageFormat.Bmp); 133 | // http://boingboing.net/2015/03/23/free-pdf-advanced-quantum-the.html 134 | pdf = new MemoryStream(Resources.advancedquantumthermodynamics); 135 | } 136 | 137 | [Test] 138 | public void ItDoesntDetectPDFs() 139 | { 140 | checker = new FileTypeChecker(new List 141 | { 142 | new FileType("Bitmap", ".bmp", new ExactFileTypeMatcher(new byte[] {0x42, 0x4d})), 143 | new FileType("Portable Network Graphic", ".png", 144 | new ExactFileTypeMatcher(new byte[] {0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A})), 145 | new FileType("JPEG", ".jpg", 146 | new FuzzyFileTypeMatcher(new byte?[] {0xFF, 0xD, 0xFF, 0xE0, null, null, 0x4A, 0x46, 0x49, 0x46, 0x00})), 147 | new FileType("Graphics Interchange Format 87a", ".gif", 148 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x37, 0x61})), 149 | new FileType("Graphics Interchange Format 89a", ".gif", 150 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x39, 0x61})) 151 | // ... Potentially more in future 152 | }); 153 | var fileTypes = checker.GetFileTypes(pdf); 154 | Assert.AreEqual(0, fileTypes.Count()); 155 | } 156 | 157 | [Test] 158 | public void ItDoesntDetectBMPs() 159 | { 160 | checker = new FileTypeChecker(new List 161 | { 162 | new FileType("Portable Network Graphic", ".png", 163 | new ExactFileTypeMatcher(new byte[] {0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A})), 164 | new FileType("JPEG", ".jpg", 165 | new FuzzyFileTypeMatcher(new byte?[] {0xFF, 0xD, 0xFF, 0xE0, null, null, 0x4A, 0x46, 0x49, 0x46, 0x00})), 166 | new FileType("Graphics Interchange Format 87a", ".gif", 167 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x37, 0x61})), 168 | new FileType("Graphics Interchange Format 89a", ".gif", 169 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x39, 0x61})), 170 | new FileType("Portable Document Format", ".pdf", new RangeFileTypeMatcher(new ExactFileTypeMatcher(new byte[] { 0x25, 0x50, 0x44, 0x46 }), 1019)) 171 | // ... Potentially more in future 172 | }); 173 | var fileTypes = checker.GetFileTypes(bitmap); 174 | Assert.AreEqual(0, fileTypes.Count()); 175 | } 176 | } 177 | } 178 | } 179 | -------------------------------------------------------------------------------- /FileTypeChecker.Tests/Properties/AssemblyInfo.cs: -------------------------------------------------------------------------------- 1 | using System.Reflection; 2 | using System.Runtime.CompilerServices; 3 | using System.Runtime.InteropServices; 4 | 5 | // General Information about an assembly is controlled through the following 6 | // set of attributes. Change these attribute values to modify the information 7 | // associated with an assembly. 8 | [assembly: AssemblyTitle("FileTypeChecker.Tests")] 9 | [assembly: AssemblyDescription("")] 10 | [assembly: AssemblyConfiguration("")] 11 | [assembly: AssemblyCompany("HP")] 12 | [assembly: AssemblyProduct("FileTypeChecker.Tests")] 13 | [assembly: AssemblyCopyright("Copyright © HP 2015")] 14 | [assembly: AssemblyTrademark("")] 15 | [assembly: AssemblyCulture("")] 16 | 17 | // Setting ComVisible to false makes the types in this assembly not visible 18 | // to COM components. If you need to access a type in this assembly from 19 | // COM, set the ComVisible attribute to true on that type. 20 | [assembly: ComVisible(false)] 21 | 22 | // The following GUID is for the ID of the typelib if this project is exposed to COM 23 | [assembly: Guid("da4da584-b4a8-4766-a0fc-81ba5b7ea1b6")] 24 | 25 | // Version information for an assembly consists of the following four values: 26 | // 27 | // Major Version 28 | // Minor Version 29 | // Build Number 30 | // Revision 31 | // 32 | // You can specify all the values or you can default the Build and Revision Numbers 33 | // by using the '*' as shown below: 34 | // [assembly: AssemblyVersion("1.0.*")] 35 | [assembly: AssemblyVersion("1.0.0.0")] 36 | [assembly: AssemblyFileVersion("1.0.0.0")] 37 | -------------------------------------------------------------------------------- /FileTypeChecker.Tests/Properties/Resources.Designer.cs: -------------------------------------------------------------------------------- 1 | //------------------------------------------------------------------------------ 2 | // 3 | // This code was generated by a tool. 4 | // Runtime Version:4.0.30319.42000 5 | // 6 | // Changes to this file may cause incorrect behavior and will be lost if 7 | // the code is regenerated. 8 | // 9 | //------------------------------------------------------------------------------ 10 | 11 | namespace FileTypeChecker.Tests.Properties { 12 | using System; 13 | 14 | 15 | /// 16 | /// A strongly-typed resource class, for looking up localized strings, etc. 17 | /// 18 | // This class was auto-generated by the StronglyTypedResourceBuilder 19 | // class via a tool like ResGen or Visual Studio. 20 | // To add or remove a member, edit your .ResX file then rerun ResGen 21 | // with the /str option, or rebuild your VS project. 22 | [global::System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "15.0.0.0")] 23 | [global::System.Diagnostics.DebuggerNonUserCodeAttribute()] 24 | [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()] 25 | internal class Resources { 26 | 27 | private static global::System.Resources.ResourceManager resourceMan; 28 | 29 | private static global::System.Globalization.CultureInfo resourceCulture; 30 | 31 | [global::System.Diagnostics.CodeAnalysis.SuppressMessageAttribute("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")] 32 | internal Resources() { 33 | } 34 | 35 | /// 36 | /// Returns the cached ResourceManager instance used by this class. 37 | /// 38 | [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)] 39 | internal static global::System.Resources.ResourceManager ResourceManager { 40 | get { 41 | if (object.ReferenceEquals(resourceMan, null)) { 42 | global::System.Resources.ResourceManager temp = new global::System.Resources.ResourceManager("FileTypeChecker.Tests.Properties.Resources", typeof(Resources).Assembly); 43 | resourceMan = temp; 44 | } 45 | return resourceMan; 46 | } 47 | } 48 | 49 | /// 50 | /// Overrides the current thread's CurrentUICulture property for all 51 | /// resource lookups using this strongly typed resource class. 52 | /// 53 | [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)] 54 | internal static global::System.Globalization.CultureInfo Culture { 55 | get { 56 | return resourceCulture; 57 | } 58 | set { 59 | resourceCulture = value; 60 | } 61 | } 62 | 63 | /// 64 | /// Looks up a localized resource of type System.Byte[]. 65 | /// 66 | internal static byte[] advancedquantumthermodynamics { 67 | get { 68 | object obj = ResourceManager.GetObject("advancedquantumthermodynamics", resourceCulture); 69 | return ((byte[])(obj)); 70 | } 71 | } 72 | 73 | /// 74 | /// Looks up a localized resource of type System.Drawing.Bitmap. 75 | /// 76 | internal static System.Drawing.Bitmap LAND { 77 | get { 78 | object obj = ResourceManager.GetObject("LAND", resourceCulture); 79 | return ((System.Drawing.Bitmap)(obj)); 80 | } 81 | } 82 | } 83 | } 84 | -------------------------------------------------------------------------------- /FileTypeChecker.Tests/Properties/Resources.resx: -------------------------------------------------------------------------------- 1 |  2 | 3 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 | 73 | 74 | 75 | 76 | 77 | 78 | 79 | 80 | 81 | 82 | 83 | 84 | 85 | 86 | 87 | 88 | 89 | 90 | 91 | 92 | 93 | 94 | 95 | 96 | 97 | 98 | 99 | 100 | 101 | 102 | 103 | 104 | 105 | 106 | 107 | 108 | 109 | text/microsoft-resx 110 | 111 | 112 | 2.0 113 | 114 | 115 | System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 116 | 117 | 118 | System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 119 | 120 | 121 | 122 | ..\Resources\advancedquantumthermodynamics.pdf;System.Byte[], mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 123 | 124 | 125 | ..\Resources\LAND.BMP;System.Drawing.Bitmap, System.Drawing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a 126 | 127 | -------------------------------------------------------------------------------- /FileTypeChecker.Tests/Resources/LAND.BMP: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/0xbrock/FileTypeChecker/65be0d72a4b388795f0fd31776d3747757918c56/FileTypeChecker.Tests/Resources/LAND.BMP -------------------------------------------------------------------------------- /FileTypeChecker.Tests/Resources/advancedquantumthermodynamics.pdf: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/0xbrock/FileTypeChecker/65be0d72a4b388795f0fd31776d3747757918c56/FileTypeChecker.Tests/Resources/advancedquantumthermodynamics.pdf -------------------------------------------------------------------------------- /FileTypeChecker.Tests/packages.config: -------------------------------------------------------------------------------- 1 |  2 | 3 | 4 | -------------------------------------------------------------------------------- /FileTypeChecker.sln: -------------------------------------------------------------------------------- 1 |  2 | Microsoft Visual Studio Solution File, Format Version 12.00 3 | # Visual Studio 15 4 | VisualStudioVersion = 15.0.27004.2005 5 | MinimumVisualStudioVersion = 10.0.40219.1 6 | Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FileTypeChecker", "FileTypeChecker\FileTypeChecker.csproj", "{0AE201D3-CE5B-404F-8C25-36BD929E1D19}" 7 | EndProject 8 | Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FileTypeChecker.Tests", "FileTypeChecker.Tests\FileTypeChecker.Tests.csproj", "{716D0AB2-5088-4A22-A6E8-24B8D2F2039B}" 9 | EndProject 10 | Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{1019EF17-64B8-4C70-BB39-A12DBFB30A16}" 11 | ProjectSection(SolutionItems) = preProject 12 | .gitignore = .gitignore 13 | README.md = README.md 14 | EndProjectSection 15 | EndProject 16 | Global 17 | GlobalSection(SolutionConfigurationPlatforms) = preSolution 18 | Debug|Any CPU = Debug|Any CPU 19 | Release|Any CPU = Release|Any CPU 20 | EndGlobalSection 21 | GlobalSection(ProjectConfigurationPlatforms) = postSolution 22 | {0AE201D3-CE5B-404F-8C25-36BD929E1D19}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 23 | {0AE201D3-CE5B-404F-8C25-36BD929E1D19}.Debug|Any CPU.Build.0 = Debug|Any CPU 24 | {0AE201D3-CE5B-404F-8C25-36BD929E1D19}.Release|Any CPU.ActiveCfg = Release|Any CPU 25 | {0AE201D3-CE5B-404F-8C25-36BD929E1D19}.Release|Any CPU.Build.0 = Release|Any CPU 26 | {716D0AB2-5088-4A22-A6E8-24B8D2F2039B}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 27 | {716D0AB2-5088-4A22-A6E8-24B8D2F2039B}.Debug|Any CPU.Build.0 = Debug|Any CPU 28 | {716D0AB2-5088-4A22-A6E8-24B8D2F2039B}.Release|Any CPU.ActiveCfg = Release|Any CPU 29 | {716D0AB2-5088-4A22-A6E8-24B8D2F2039B}.Release|Any CPU.Build.0 = Release|Any CPU 30 | EndGlobalSection 31 | GlobalSection(SolutionProperties) = preSolution 32 | HideSolutionNode = FALSE 33 | EndGlobalSection 34 | GlobalSection(ExtensibilityGlobals) = postSolution 35 | SolutionGuid = {113B3F98-0519-459D-91A6-EE74FABE92E6} 36 | EndGlobalSection 37 | EndGlobal 38 | -------------------------------------------------------------------------------- /FileTypeChecker/App.config: -------------------------------------------------------------------------------- 1 |  2 | 3 | 4 | 5 | 6 | -------------------------------------------------------------------------------- /FileTypeChecker/ExactFileTypeMatcher.cs: -------------------------------------------------------------------------------- 1 | namespace FileTypeChecker 2 | { 3 | using System.Collections.Generic; 4 | using System.IO; 5 | using System.Linq; 6 | 7 | public class ExactFileTypeMatcher : FileTypeMatcher 8 | { 9 | private readonly byte[] bytes; 10 | 11 | public ExactFileTypeMatcher(IEnumerable bytes) 12 | { 13 | this.bytes = bytes.ToArray(); 14 | } 15 | 16 | protected override bool MatchesPrivate(Stream stream) 17 | { 18 | foreach (var b in bytes) 19 | { 20 | if (stream.ReadByte() != b) 21 | { 22 | return false; 23 | } 24 | } 25 | 26 | return true; 27 | } 28 | } 29 | } 30 | -------------------------------------------------------------------------------- /FileTypeChecker/FileType.cs: -------------------------------------------------------------------------------- 1 | namespace FileTypeChecker 2 | { 3 | using System.IO; 4 | 5 | public class FileType 6 | { 7 | private static readonly FileType unknown = new FileType("unknown", string.Empty, null); 8 | 9 | private readonly string name; 10 | 11 | private readonly string extension; 12 | 13 | private readonly FileTypeMatcher fileTypeMatcher; 14 | 15 | public string Name { get { return name; } } 16 | 17 | public string Extension { get { return extension; } } 18 | 19 | public static FileType Unknown { get { return unknown; } } 20 | 21 | public FileType(string name, string extension, FileTypeMatcher matcher) 22 | { 23 | this.name = name; 24 | this.extension = extension; 25 | this.fileTypeMatcher = matcher; 26 | } 27 | 28 | public bool Matches(Stream stream) 29 | { 30 | return this.fileTypeMatcher == null || this.fileTypeMatcher.Matches(stream); 31 | } 32 | } 33 | } 34 | -------------------------------------------------------------------------------- /FileTypeChecker/FileTypeChecker.cs: -------------------------------------------------------------------------------- 1 | namespace FileTypeChecker 2 | { 3 | using System.Collections.Generic; 4 | using System.IO; 5 | using System.Linq; 6 | 7 | public class FileTypeChecker : IFileTypeChecker 8 | { 9 | private IList knownFileTypes; 10 | 11 | public FileTypeChecker() 12 | { 13 | this.knownFileTypes = new List 14 | { 15 | new FileType("Bitmap", ".bmp", new ExactFileTypeMatcher(new byte[] {0x42, 0x4d})), 16 | new FileType("Portable Network Graphic", ".png", 17 | new ExactFileTypeMatcher(new byte[] {0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A})), 18 | new FileType("JPEG", ".jpg", 19 | new FuzzyFileTypeMatcher(new byte?[] {0xFF, 0xD, 0xFF, 0xE0, null, null, 0x4A, 0x46, 0x49, 0x46, 0x00})), 20 | new FileType("Graphics Interchange Format 87a", ".gif", 21 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x37, 0x61})), 22 | new FileType("Graphics Interchange Format 89a", ".gif", 23 | new ExactFileTypeMatcher(new byte[] {0x47, 0x49, 0x46, 0x38, 0x39, 0x61})), 24 | new FileType("Portable Document Format", ".pdf", new RangeFileTypeMatcher(new ExactFileTypeMatcher(new byte[] { 0x25, 0x50, 0x44, 0x46 }), 1019)) 25 | // ... Potentially more in future 26 | }; 27 | } 28 | 29 | public FileTypeChecker(IList knownFileTypes) 30 | { 31 | this.knownFileTypes = knownFileTypes; 32 | } 33 | 34 | public FileType GetFileType(Stream fileContent) 35 | { 36 | return GetFileTypes(fileContent).FirstOrDefault() ?? FileType.Unknown; 37 | } 38 | 39 | public IEnumerable GetFileTypes(Stream stream) 40 | { 41 | return knownFileTypes.Where(fileType => fileType.Matches(stream)); 42 | } 43 | } 44 | } 45 | -------------------------------------------------------------------------------- /FileTypeChecker/FileTypeChecker.csproj: -------------------------------------------------------------------------------- 1 |  2 | 3 | 4 | 5 | Debug 6 | AnyCPU 7 | {0AE201D3-CE5B-404F-8C25-36BD929E1D19} 8 | Library 9 | Properties 10 | FileTypeChecker 11 | FileTypeChecker 12 | v4.5 13 | 512 14 | 15 | 16 | AnyCPU 17 | true 18 | full 19 | false 20 | bin\Debug\ 21 | DEBUG;TRACE 22 | prompt 23 | 4 24 | 25 | 26 | AnyCPU 27 | pdbonly 28 | true 29 | bin\Release\ 30 | TRACE 31 | prompt 32 | 4 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 66 | -------------------------------------------------------------------------------- /FileTypeChecker/FileTypeChecker.nuspec: -------------------------------------------------------------------------------- 1 |  2 | 3 | 4 | FileTypeChecker 5 | 1.0.0 6 | File Type Checker 7 | 0xbrock 8 | https://github.com/0xbrock/FileTypeChecker 9 | false 10 | File type checker that checks the file's magic numbers/Identifying bytes. Useful for verifying uploaded files in web applications. 11 | NuGet package of code originally written by https://github.com/mjolka and extended to allow for dependency injecting the known file types. 12 | 2017 13 | File Type, Validator, Checker, Magic Numbers, Identifying Bytes 14 | 15 | 16 | 17 | 18 | -------------------------------------------------------------------------------- /FileTypeChecker/FileTypeMatcher.cs: -------------------------------------------------------------------------------- 1 | namespace FileTypeChecker 2 | { 3 | using System; 4 | using System.IO; 5 | 6 | public abstract class FileTypeMatcher 7 | { 8 | public bool Matches(Stream stream, bool resetPosition = true) 9 | { 10 | if (stream == null) 11 | { 12 | throw new ArgumentNullException("stream"); 13 | } 14 | if (!stream.CanRead || (stream.Position != 0 && !stream.CanSeek)) 15 | { 16 | throw new ArgumentException("File contents must be a readable stream", "stream"); 17 | } 18 | if (stream.Position != 0 && resetPosition) 19 | { 20 | stream.Seek(0, SeekOrigin.Begin); 21 | } 22 | 23 | return MatchesPrivate(stream); 24 | } 25 | 26 | protected abstract bool MatchesPrivate(Stream stream); 27 | } 28 | } 29 | -------------------------------------------------------------------------------- /FileTypeChecker/FuzzyFileTypeMatcher.cs: -------------------------------------------------------------------------------- 1 | namespace FileTypeChecker 2 | { 3 | using System.Collections.Generic; 4 | using System.IO; 5 | using System.Linq; 6 | 7 | public class FuzzyFileTypeMatcher : FileTypeMatcher 8 | { 9 | private readonly byte?[] bytes; 10 | 11 | public FuzzyFileTypeMatcher(IEnumerable bytes) 12 | { 13 | this.bytes = bytes.ToArray(); 14 | } 15 | 16 | protected override bool MatchesPrivate(Stream stream) 17 | { 18 | foreach (var b in this.bytes) 19 | { 20 | var c = stream.ReadByte(); 21 | if (c == -1 || (b.HasValue && c != b.Value)) 22 | { 23 | return false; 24 | } 25 | } 26 | 27 | return true; 28 | } 29 | } 30 | } 31 | -------------------------------------------------------------------------------- /FileTypeChecker/IFileTypeChecker.cs: -------------------------------------------------------------------------------- 1 | using System.Collections.Generic; 2 | using System.IO; 3 | 4 | namespace FileTypeChecker 5 | { 6 | public interface IFileTypeChecker 7 | { 8 | FileType GetFileType(Stream fileContent); 9 | IEnumerable GetFileTypes(Stream stream); 10 | } 11 | } -------------------------------------------------------------------------------- /FileTypeChecker/Properties/AssemblyInfo.cs: -------------------------------------------------------------------------------- 1 | using System.Reflection; 2 | using System.Runtime.CompilerServices; 3 | using System.Runtime.InteropServices; 4 | 5 | // General Information about an assembly is controlled through the following 6 | // set of attributes. Change these attribute values to modify the information 7 | // associated with an assembly. 8 | [assembly: AssemblyTitle("FileTypeChecker")] 9 | [assembly: AssemblyDescription("")] 10 | [assembly: AssemblyConfiguration("")] 11 | [assembly: AssemblyCompany("HP")] 12 | [assembly: AssemblyProduct("FileTypeChecker")] 13 | [assembly: AssemblyCopyright("Copyright © HP 2015")] 14 | [assembly: AssemblyTrademark("")] 15 | [assembly: AssemblyCulture("")] 16 | 17 | // Setting ComVisible to false makes the types in this assembly not visible 18 | // to COM components. If you need to access a type in this assembly from 19 | // COM, set the ComVisible attribute to true on that type. 20 | [assembly: ComVisible(false)] 21 | 22 | // The following GUID is for the ID of the typelib if this project is exposed to COM 23 | [assembly: Guid("8f5ab3ff-cefb-4575-bbda-58ca0dc9b369")] 24 | 25 | // Version information for an assembly consists of the following four values: 26 | // 27 | // Major Version 28 | // Minor Version 29 | // Build Number 30 | // Revision 31 | // 32 | // You can specify all the values or you can default the Build and Revision Numbers 33 | // by using the '*' as shown below: 34 | // [assembly: AssemblyVersion("1.0.*")] 35 | [assembly: AssemblyVersion("1.0.0.0")] 36 | [assembly: AssemblyFileVersion("1.0.0.0")] 37 | -------------------------------------------------------------------------------- /FileTypeChecker/RangeFileTypeMatcher.cs: -------------------------------------------------------------------------------- 1 | namespace FileTypeChecker 2 | { 3 | using System.IO; 4 | 5 | public class RangeFileTypeMatcher : FileTypeMatcher 6 | { 7 | private readonly FileTypeMatcher matcher; 8 | 9 | private readonly int maximumStartLocation; 10 | 11 | public RangeFileTypeMatcher(FileTypeMatcher matcher, int maximumStartLocation) 12 | { 13 | this.matcher = matcher; 14 | this.maximumStartLocation = maximumStartLocation; 15 | } 16 | 17 | protected override bool MatchesPrivate(Stream stream) 18 | { 19 | for (var i = 0; i < this.maximumStartLocation; i++) 20 | { 21 | stream.Position = i; 22 | if (matcher.Matches(stream, resetPosition: false)) 23 | { 24 | return true; 25 | } 26 | } 27 | 28 | return false; 29 | } 30 | } 31 | } 32 | -------------------------------------------------------------------------------- /LICENSE.md: -------------------------------------------------------------------------------- 1 | The MIT License (MIT) 2 | 3 | Copyright (c) 2015-present Dan Abramov 4 | 5 | Permission is hereby granted, free of charge, to any person obtaining a copy 6 | of this software and associated documentation files (the "Software"), to deal 7 | in the Software without restriction, including without limitation the rights 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 9 | copies of the Software, and to permit persons to whom the Software is 10 | furnished to do so, subject to the following conditions: 11 | 12 | The above copyright notice and this permission notice shall be included in all 13 | copies or substantial portions of the Software. 14 | 15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 | SOFTWARE. 22 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # File Type Checker 2 | 3 | File Type Checker is a .Net file identification library allowing developers to verify the file's magic numbers/identifying bytes against a whitelist. 4 | 5 | The purpose of this code is to make it easier for people to add better file security functionality to their projects via a NuGet package. 6 | 7 | ## Installation 8 | 9 | Nuget package: [FileTypeChecker](https://www.nuget.org/packages/FileTypeChecker/) 10 | 11 | Via Package Manager: 12 | 13 | `Install-Package FileTypeChecker` 14 | 15 | ## Usage 16 | 17 | Using an IoC container, register the instance in the container 18 | 19 | ```C# 20 | new List 21 | { 22 | new FileType("Portable Network Graphic", ".png", 23 | new ExactFileTypeMatcher(new byte[] {0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A})), 24 | new FileType("JPEG", ".jpg", 25 | new FuzzyFileTypeMatcher(new byte?[] {0xFF, 0xD, 0xFF, 0xE0, null, null, 0x4A, 0x46, 0x49, 0x46, 0x00})), 26 | new FileType("Portable Document Format", ".pdf", new RangeFileTypeMatcher(new ExactFileTypeMatcher(new byte[] { 0x25, 0x50, 0x44, 0x46 }), 1019)) 27 | } 28 | ``` 29 | 30 | Register the `FileTypeChecker` concrete implementation to the `IFileTypeChecker` interface. Wherever you need the checker, dependency inject it and use it like below. 31 | ```C# 32 | // pdf is a stream containing a PDF 33 | var fileType = checker.GetFileType(pdf); 34 | ``` 35 | 36 | 37 | ## Background 38 | 39 | I have seen too many projects allow file uploads any the only validation that occurs is the filename extension. This project exists because there needs to be a plug and play library that facilites mitigating this security issue. 40 | 41 | 42 | ## File Magic Number Resources 43 | 44 | For a list of file magic numbers, I have found these sites to be useful. 45 | 46 | * [https://www.garykessler.net/library/file_sigs.html](https://www.garykessler.net/library/file_sigs.html) 47 | * [http://filext.com/](http://filext.com/) 48 | * [https://en.wikipedia.org/wiki/List_of_file_signatures](https://en.wikipedia.org/wiki/List_of_file_signatures) 49 | * [https://asecuritysite.com/forensics/magic](https://asecuritysite.com/forensics/magic) 50 | 51 | 52 | ## Credits 53 | 54 | Based on [mjolka](https://github.com/mjolka)'s answer to the Stack Overflow question [Guessing a file type based on its content](http://codereview.stackexchange.com/questions/85054/guessing-a-file-type-based-on-its-content). 55 | 56 | This repo is forked from [https://github.com/mjolka/filetypes](https://github.com/mjolka/filetypes) and the original code can be found in the "original" branch (preserving for posterity). I have changed the namespaces/project name to better describe the purpose. 57 | --------------------------------------------------------------------------------