Read part of NCA header

hactoolnet/Program.cs

@@ -1,8 +1,9 @@
 using System.IO;
+using libhac;
 
-namespace libhac
+namespace hactoolnet
 {
-    class Program
+    public static class Program
     {
         static void Main(string[] args)
         {
@@ -10,11 +11,14 @@ namespace libhac
             keyset.SetSdSeed(args[1].ToBytes());
 
             var nax0 = new Nax0(keyset, args[2], args[3]);
+            var nca = new Nca(keyset, nax0.Stream);
+
             using (var output = new FileStream(args[4], FileMode.Create))
             using (var progress = new ProgressBar())
             {
+                progress.LogMessage($"Title ID: {nca.TitleId:X8}");
                 progress.LogMessage($"Writing {args[4]}");
-                Util.CopyStream(nax0.Stream, output, nax0.Stream.Length, progress);
+                nax0.Stream.CopyStream(output, nax0.Stream.Length, progress);
             }
         }
     }

hactoolnet/hactoolnet.csproj

@@ -0,0 +1,12 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp2.1</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\libhac\libhac.csproj" />
+  </ItemGroup>
+
+</Project>

libhac.sln

@@ -3,7 +3,9 @@ Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 15
 VisualStudioVersion = 15.0.27703.2026
 MinimumVisualStudioVersion = 10.0.40219.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "libhac", "libhac\libhac.csproj", "{FFCA6C31-D9D4-4ED8-A06D-0CC6B94422B8}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "libhac", "libhac\libhac.csproj", "{FFCA6C31-D9D4-4ED8-A06D-0CC6B94422B8}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "hactoolnet", "hactoolnet\hactoolnet.csproj", "{B1633A64-125F-40A3-9E15-654B4DE5FD98}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -15,6 +17,10 @@ Global
 		{FFCA6C31-D9D4-4ED8-A06D-0CC6B94422B8}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{FFCA6C31-D9D4-4ED8-A06D-0CC6B94422B8}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{FFCA6C31-D9D4-4ED8-A06D-0CC6B94422B8}.Release|Any CPU.Build.0 = Release|Any CPU
+		{B1633A64-125F-40A3-9E15-654B4DE5FD98}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{B1633A64-125F-40A3-9E15-654B4DE5FD98}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{B1633A64-125F-40A3-9E15-654B4DE5FD98}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{B1633A64-125F-40A3-9E15-654B4DE5FD98}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

libhac/Nca.cs

@@ -0,0 +1,53 @@
+using System.IO;
+using libhac.XTSSharp;
+
+namespace libhac
+{
+    public class Nca
+    {
+        public byte[] Signature1 { get; set; } // RSA-PSS signature over header with fixed key.
+        public byte[] Signature2 { get; set; } // RSA-PSS signature over header with key in NPDM.
+        public string Magic { get; set; }
+        public byte Distribution { get; set; } // System vs gamecard.
+        public byte ContentType { get; set; }
+        public byte CryptoType { get; set; } // Which keyblob (field 1)
+        public byte KaekInd { get; set; } // Which kaek index?
+        public ulong NcaSize { get; set; } // Entire archive size.
+        public ulong TitleId { get; set; }
+        public uint SdkVersion { get; set; } // What SDK was this built with?
+        public byte CryptoType2 { get; set; } // Which keyblob (field 2)
+        public byte[] RightsId { get; set; }
+
+        public Nca(Keyset keyset, Stream stream)
+        {
+            ReadHeader(keyset, stream);
+        }
+
+        private void ReadHeader(Keyset keyset, Stream stream)
+        {
+            stream.Position = 0;
+            var xts = XtsAes128.Create(keyset.header_key);
+            var header = new RandomAccessSectorStream(new XtsSectorStream(stream, xts, 0x200));
+            var reader = new BinaryReader(header);
+
+            Signature1 = reader.ReadBytes(0x100);
+            Signature2 = reader.ReadBytes(0x100);
+            Magic = reader.ReadAscii(4);
+            if (Magic != "NCA3") throw new InvalidDataException("Not an NCA3 file");
+            Distribution = reader.ReadByte();
+            ContentType = reader.ReadByte();
+            CryptoType = reader.ReadByte();
+            KaekInd = reader.ReadByte();
+            NcaSize = reader.ReadUInt64();
+            TitleId = reader.ReadUInt64();
+            header.Position += 4;
+
+            SdkVersion = reader.ReadUInt32();
+            CryptoType2 = reader.ReadByte();
+            header.Position += 0xF;
+
+            RightsId = reader.ReadBytes(0x10);
+            header.Close();
+        }
+    }
+}

libhac/Util.cs

@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using System.Text;
 
 namespace libhac
 {
@@ -73,6 +74,12 @@ namespace libhac
             }
         }
 
+        public static string ReadAscii(this BinaryReader reader, int size)
+        {
+            return Encoding.ASCII.GetString(reader.ReadBytes(size), 0, size);
+        }
+
+
         private static int HexToInt(char c)
         {
             switch (c)

libhac/libhac.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <OutputType>Exe</OutputType>
+    <OutputType>Library</OutputType>
     <TargetFramework>netcoreapp2.1</TargetFramework>
     <LangVersion>7.3</LangVersion>
   </PropertyGroup>