Merge pull request #1073 from Ottermandias/SigScanner

Dalamud/Game/SigScanner.cs

@@ -9,6 +9,7 @@ using System.Runtime.InteropServices;
 
 using Dalamud.IoC;
 using Dalamud.IoC.Internal;
+using Iced.Intel;
 using Newtonsoft.Json;
 using Serilog;
 
@@ -173,26 +174,36 @@ public class SigScanner : IDisposable, IServiceType
     /// Scan for a .data address using a .text function.
     /// This is intended to be used with IDA sigs.
     /// Place your cursor on the line calling a static address, and create and IDA sig.
+    /// The signature and offset should not break through instruction boundaries.
     /// </summary>
     /// <param name="signature">The signature of the function using the data.</param>
     /// <param name="offset">The offset from function start of the instruction using the data.</param>
     /// <returns>An IntPtr to the static memory location.</returns>
-    public IntPtr GetStaticAddressFromSig(string signature, int offset = 0)
+    public unsafe IntPtr GetStaticAddressFromSig(string signature, int offset = 0)
     {
-        var instrAddr = this.ScanText(signature);
+        var instructionAddress = (byte*)this.ScanText(signature);
-        instrAddr = IntPtr.Add(instrAddr, offset);
+        instructionAddress += offset;
-        var bAddr = (long)this.Module.BaseAddress;
-        long num;
 
-        do
+        try
         {
-            instrAddr = IntPtr.Add(instrAddr, 1);
+            var reader = new UnsafeCodeReader(instructionAddress, signature.Length + 8);
-            num = Marshal.ReadInt32(instrAddr) + (long)instrAddr + 4 - bAddr;
+            var decoder = Decoder.Create(64, reader, (ulong)instructionAddress, DecoderOptions.AMD);
+            while (reader.CanReadByte)
+            {
+                var instruction = decoder.Decode();
+                if (instruction.IsInvalid) continue;
+                if (instruction.Op0Kind is OpKind.Memory || instruction.Op1Kind is OpKind.Memory)
+                {
+                    return (IntPtr)instruction.MemoryDisplacement64;
+                }
+            }
+        }
+        catch
+        {
+            // ignored
         }
-        while (!(num >= this.DataSectionOffset && num <= this.DataSectionOffset + this.DataSectionSize)
-               && !(num >= this.RDataSectionOffset && num <= this.RDataSectionOffset + this.RDataSectionSize));
 
-        return IntPtr.Add(instrAddr, Marshal.ReadInt32(instrAddr) + 4);
+        throw new KeyNotFoundException($"Can't find any referenced address in the given signature {signature}.");
     }
 
     /// <summary>
@@ -384,6 +395,26 @@ public class SigScanner : IDisposable, IServiceType
         }
     }
 
+    private unsafe class UnsafeCodeReader : CodeReader
+    {
+        private readonly int length;
+        private readonly byte* address;
+        private int pos;
+        public UnsafeCodeReader(byte* address, int length)
+        {
+            this.length  = length;
+            this.address = address;
+        }
+
+        public bool CanReadByte => this.pos < this.length;
+
+        public override int ReadByte()
+        {
+            if (this.pos >= this.length) return -1;
+            return *(this.address + this.pos++);
+        }
+    }
+
     /// <summary>
     /// Helper for ScanText to get the correct address for IDA sigs that mark the first JMP or CALL location.
     /// </summary>