An attempt to implement memory translation for sections

serge1 · Sep 19, 2021 · b527ea9 · b527ea9
1 parent 0a15ec0
commit b527ea9
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Showing 4 changed files with 17 additions and 10 deletions.
diff --git a/.vscode/launch.json b/.vscode/launch.json
@@ -58,6 +58,7 @@
                 "2919",
                 "/usr/bin/bash"
             ],
+            "sudo" : true,
             "stopAtEntry": false,
             "cwd": "${workspaceFolder}",
             "environment": [],
@@ -70,7 +71,7 @@
                     "ignoreFailures": true
                 }
             ],
-            "miDebuggerPath": "/usr/bin/gdb"
+            "miDebuggerPath": "/home/user/ELFIO/mygdb.sh"
         }
     ]
 }
diff --git a/elfio/elfio.hpp b/elfio/elfio.hpp
@@ -421,10 +421,12 @@ class elfio
         unsigned char file_class  = get_class();
 
         if ( file_class == ELFCLASS64 ) {
-            new_section = new section_impl<Elf64_Shdr>( &convertor );
+            new_section =
+                new section_impl<Elf64_Shdr>( &convertor, &addr_translator );
         }
         else if ( file_class == ELFCLASS32 ) {
-            new_section = new section_impl<Elf32_Shdr>( &convertor );
+            new_section =
+                new section_impl<Elf32_Shdr>( &convertor, &addr_translator );
         }
         else {
             return nullptr;

diff --git a/elfio/elfio_section.hpp b/elfio/elfio_section.hpp
@@ -72,8 +72,9 @@ template <class T> class section_impl : public section
 {
   public:
     //------------------------------------------------------------------------------
-    section_impl( const endianess_convertor* convertor )
-        : convertor( convertor )
+    section_impl( const endianess_convertor* convertor,
+                  const address_translator*  translator )
+        : convertor( convertor ), translator( translator )
     {
         std::fill_n( reinterpret_cast<char*>( &header ), sizeof( header ),
                      '\0' );
@@ -192,10 +193,10 @@ template <class T> class section_impl : public section
         std::fill_n( reinterpret_cast<char*>( &header ), sizeof( header ),
                      '\0' );
 
-        stream.seekg( 0, stream.end );
-        set_stream_size( stream.tellg() );
+        // stream.seekg( 0, stream.end );
+        set_stream_size( 0xFFFFFFFF /*stream.tellg()*/ );
 
-        stream.seekg( header_offset );
+        stream.seekg( ( *translator )( header_offset ) );
         stream.read( reinterpret_cast<char*>( &header ), sizeof( header ) );
 
         Elf_Xword size = get_size();
@@ -204,7 +205,8 @@ template <class T> class section_impl : public section
             data = new ( std::nothrow ) char[size + 1];
 
             if ( ( 0 != size ) && ( nullptr != data ) ) {
-                stream.seekg( ( *convertor )( header.sh_offset ) );
+                stream.seekg(
+                    ( *translator )( ( *convertor )( header.sh_offset ) ) );
                 stream.read( data, size );
                 data[size] = 0; // Ensure data is ended with 0 to avoid oob read
                 data_size  = size;
@@ -263,6 +265,7 @@ template <class T> class section_impl : public section
     char*                      data;
     Elf_Word                   data_size;
     const endianess_convertor* convertor;
+    const address_translator*  translator;
     bool                       is_address_set;
     size_t                     stream_size;
 };

diff --git a/elfio/elfio_utils.hpp b/elfio/elfio_utils.hpp
@@ -190,7 +190,8 @@ class address_translator
         for ( auto& t : translation ) {
             if ( t.map_to <= value &&
                  ( ( value - t.map_to ) < ( t.end - t.start ) ) ) {
-                std::cout << std::hex << t.start - t.map_to + value << std::endl;
+                std::cout << std::hex << t.start - t.map_to + value << " "
+                          << value << std::endl;
                 return t.start - t.map_to + value;
             }
         }