x86 Integrity check

x86/example.vcxproj

@@ -169,6 +169,7 @@
     <ClInclude Include="lib\curl\urlapi.h" />
     <ClInclude Include="lib\hmac_sha256.h" />
     <ClInclude Include="lib\includes.hpp" />
+    <ClInclude Include="lib\integrity.h" />
     <ClInclude Include="lib\nlohmann\adl_serializer.hpp" />
     <ClInclude Include="lib\nlohmann\byte_container_with_subtype.hpp" />
     <ClInclude Include="lib\nlohmann\detail\conversions\from_json.hpp" />

x86/example.vcxproj.filters

@@ -200,6 +200,9 @@
     <ClInclude Include="lib\xorstr.hpp">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="lib\integrity.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <Library Include="lib\curl\libcurl.lib" />

x86/lib/auth.cpp

@@ -55,6 +55,7 @@
 #include <algorithm>
 
 #include "Security.hpp"
+#include "integrity.h"
 
 #define SHA256_HASH_SIZE 32
 
@@ -71,9 +72,7 @@ bool initalized;
 
 void KeyAuth::api::init()
 {
-    #if defined(__x86_64__) || defined(_M_X64)
-        CreateThread(0, 0, (LPTHREAD_START_ROUTINE)modify, 0, 0, 0);
-    #endif
+    CreateThread(0, 0, (LPTHREAD_START_ROUTINE)modify, 0, 0, 0);
 
     if (ownerid.length() != 10 || secret.length() != 64)
     {
@@ -1454,7 +1453,11 @@ void error(std::string message) {
         return patched;
     }
 #elif defined(__i386) || defined(_M_IX86)
-
+    // code submitted in pull request from https://github.com/autumnlikescode authored by https://github.com/Vasie1337/integrity-check
+    auto check_section_integrity() {
+        _integrity_check check;
+        return check.check_integrity();
+    }
 #endif
 
 std::string checksum()
@@ -1691,5 +1694,12 @@ DWORD64 FindPattern(BYTE* bMask, const char* szMask)
         }
     }
 #elif defined(__i386) || defined(_M_IX86)
-
+// code submitted in pull request from https://github.com/autumnlikescode authored by https://github.com/Vasie1337/integrity-check
+    void modify() {
+        while (true) {
+            if (check_section_integrity()) {
+                error(XorStr("check_section_integrity() failed, don't tamper with the program."));
+            }
+        }
+    }
 #endif

x86/lib/integrity.h

@@ -0,0 +1,63 @@
+#pragma once
+#include <iostream>
+#include <Windows.h>
+#include <nmmintrin.h>
+
+typedef struct _integrity_check
+{
+    struct section {
+        std::uint8_t* name = {};
+        void* address = {};
+        std::uint32_t checksum = {};
+
+        bool operator==(section& other)
+        {
+            return checksum == other.checksum;
+        }
+    }; section _cached;
+
+    _integrity_check()
+    {
+        _cached = get_text_section(reinterpret_cast<std::uintptr_t>(GetModuleHandle(nullptr)));
+    }
+
+    std::uint32_t crc32(void* data, std::size_t size)
+    {
+        std::uint32_t result = {};
+
+        for (std::size_t index = {}; index < size; ++index)
+            result = _mm_crc32_u32(result, reinterpret_cast<std::uint8_t*>(data)[index]);
+
+        return result;
+    }
+
+    section get_text_section(std::uintptr_t module)
+    {
+        section text_section = {};
+
+        PIMAGE_DOS_HEADER dosheader = reinterpret_cast<PIMAGE_DOS_HEADER>(module);
+        PIMAGE_NT_HEADERS nt_headers = reinterpret_cast<PIMAGE_NT_HEADERS>(module + dosheader->e_lfanew);
+
+        PIMAGE_SECTION_HEADER section = IMAGE_FIRST_SECTION(nt_headers);
+
+        for (int i = 0; i < nt_headers->FileHeader.NumberOfSections; i++, section++)
+        {
+            std::string name(reinterpret_cast<char const*>(section->Name));
+            if (name != ".text")
+                continue;
+
+            void* address = reinterpret_cast<void*>(module + section->VirtualAddress);
+            text_section = { section->Name, address, crc32(address, section->Misc.VirtualSize) };
+        }
+        return text_section;
+    }
+    /// <summary>
+    /// Checks .text integrity.
+    /// </summary>
+    /// <returns>Returns true if it has been changed.</returns>
+    bool check_integrity()
+    {
+        section section2 = get_text_section(reinterpret_cast<std::uintptr_t>(GetModuleHandle(nullptr)));
+        return (!(_cached == section2));
+    }
+};