protected void ApplyRelocations( BinaryReader reader, IMemory memory, ElfSection section, uint baseAddress )
{
List<HiReloc> hiRelocs = new List<HiReloc>();
ElfSection linked = section.Reference;
if( ( linked.Flags & ElfSectionFlags.Alloc ) != ElfSectionFlags.Alloc )
return;
Debug.WriteLine( string.Format( "Relocating section {0} using {1}, {2} relocations total", linked.Name, section.Name, section.Length / 8 ) );
ElfSection textSection = _sectionLookup[ ".text" ];
ElfSection dataSection = _sectionLookup[ ".data" ];
Debug.Assert( textSection != null );
Debug.Assert( dataSection != null );
for( int n = 0; n < section.Length / 8; n++ )
{
reader.BaseStream.Seek( section.ElfOffset + ( 8 * n ), SeekOrigin.Begin );
NativeElfRel rel = new NativeElfRel( reader );
ElfRelocation relocation = new ElfRelocation();
//relocation.Section = section;
relocation.Offset = rel.Offset;
relocation.BaseAddress = ( rel.Info >> 16 ) & 0xFF;
relocation.Symbol = ( rel.Info >> 8 ) & 0xFF;
relocation.RelocationType = ( ElfRelocationType )( byte )( rel.Info & 0xFF );
uint pointer = relocation.Offset;
//ElfSection offsetBase = null;
//ElfSection addressBase = null;
if( ( relocation.Symbol & ( uint )RelocationOffset.Data ) == ( uint )RelocationOffset.Data )
{
//offsetBase = dataSection;
pointer += dataSection.Address;
}
//else if( relocation.BaseAddress == 0x1 )
//{
// offsetBase = textSection;
// pointer += textSection.Address;
//}
else
{
//offsetBase = textSection;
pointer += baseAddress;
}
//ElfSection offsetBase = _sections[ ( int )relocation.Symbol ];
//ElfSection addressBase = _sections[ ( int )relocation.BaseAddress ];
// Happens sometime
if( _symbols.Count == 0 )
{
Debug.WriteLine( "Unable to relocate symbol; symbol table is empty - possibly no .symtab section?" );
return;
}
ElfSymbol symbol = _symbols[ ( int )relocation.Symbol ];
uint symbolValue = symbol.Value;
// !!! This could be bogus
if( ( ( rel.Info >> 8 ) & RelocationRelativeData ) == RelocationRelativeData )
symbolValue += dataSection.Address;
else
symbolValue += baseAddress;
//if( addressBase.Address == 0 )
// symbolValue += baseAddress;
//else
// symbolValue += addressBase.Address;
uint value = ( uint )memory.ReadWord( ( int )pointer );
//Debug.WriteLine( string.Format( " Relocation pointer 0x{0:X8} (elf {1:X8}), value {2:X8}, type {3}, existing memory value {4:X8}",
// pointer, relocation.Offset, symbolValue, relocation.RelocationType, value ) );
bool writeMemory = false;
switch( relocation.RelocationType )
{
case ElfRelocationType.None:
break;
case ElfRelocationType.Mips32:
value += symbolValue;
writeMemory = true;
break;
case ElfRelocationType.Mips26:
Debug.Assert( symbolValue % 4 == 0 );
value = ( uint )( ( value & ~0x03FFFFFF ) | ( ( value + ( symbolValue >> 2 ) ) & 0x03FFFFFF ) );
writeMemory = true;
break;
case ElfRelocationType.Hi16:
{
HiReloc hiReloc = new HiReloc();
hiReloc.Address = pointer;
hiReloc.Value = symbolValue;
hiRelocs.Add( hiReloc );
}
break;
case ElfRelocationType.Lo16:
{
uint vallo = ( ( value & 0x0000FFFF ) ^ 0x00008000 ) - 0x00008000;
while( hiRelocs.Count > 0 )
{
HiReloc hiReloc = hiRelocs[ hiRelocs.Count - 1 ];
hiRelocs.RemoveAt( hiRelocs.Count - 1 );
Debug.Assert( hiReloc.Value == symbolValue );
uint value2 = ( uint )memory.ReadWord( ( int )hiReloc.Address );
uint temp = ( ( value2 & 0x0000FFFF ) << 16 ) + vallo;
temp += symbolValue;
temp = ( ( temp >> 16 ) + ( ( ( temp & 0x00008000 ) != 0 ) ? ( uint )1 : ( uint )0 ) ) & 0x0000FFFF;
value2 = ( uint )( ( value2 & ~0x0000FFFF ) | temp );
//Debug.WriteLine( string.Format( " Updating memory at 0x{0:X8} to {1:X8} (from previous HI16)", hiReloc.Address, value2 ) );
memory.WriteWord( ( int )hiReloc.Address, 4, ( int )value2 );
}
value = ( uint )( ( value & ~0x0000FFFF ) | ( ( symbolValue + vallo ) & 0x0000FFFF ) );
}
writeMemory = true;
break;
default:
// Unsupported type
Debugger.Break();
break;
}
if( writeMemory == true )
{
//Debug.WriteLine( string.Format( " Updating memory at 0x{0:X8} to {1:X8}", pointer, value ) );
memory.WriteWord( ( int )pointer, 4, ( int )value );
}
}
}
protected void ApplyRelocations(BinaryReader reader, IMemory memory, ElfSection section, uint baseAddress)
{
List <HiReloc> hiRelocs = new List <HiReloc>();
ElfSection linked = section.Reference;
if ((linked.Flags & ElfSectionFlags.Alloc) != ElfSectionFlags.Alloc)
{
return;
}
Debug.WriteLine(string.Format("Relocating section {0} using {1}, {2} relocations total", linked.Name, section.Name, section.Length / 8));
ElfSection textSection = _sectionLookup[".text"];
ElfSection dataSection = _sectionLookup[".data"];
Debug.Assert(textSection != null);
Debug.Assert(dataSection != null);
for (int n = 0; n < section.Length / 8; n++)
{
reader.BaseStream.Seek(section.ElfOffset + (8 * n), SeekOrigin.Begin);
NativeElfRel rel = new NativeElfRel(reader);
ElfRelocation relocation = new ElfRelocation();
//relocation.Section = section;
relocation.Offset = rel.Offset;
relocation.BaseAddress = (rel.Info >> 16) & 0xFF;
relocation.Symbol = (rel.Info >> 8) & 0xFF;
relocation.RelocationType = ( ElfRelocationType )( byte )(rel.Info & 0xFF);
uint pointer = relocation.Offset;
//ElfSection offsetBase = null;
//ElfSection addressBase = null;
if ((relocation.Symbol & ( uint )RelocationOffset.Data) == ( uint )RelocationOffset.Data)
{
//offsetBase = dataSection;
pointer += dataSection.Address;
}
//else if( relocation.BaseAddress == 0x1 )
//{
// offsetBase = textSection;
// pointer += textSection.Address;
//}
else
{
//offsetBase = textSection;
pointer += baseAddress;
}
//ElfSection offsetBase = _sections[ ( int )relocation.Symbol ];
//ElfSection addressBase = _sections[ ( int )relocation.BaseAddress ];
// Happens sometime
if (_symbols.Count == 0)
{
Debug.WriteLine("Unable to relocate symbol; symbol table is empty - possibly no .symtab section?");
return;
}
ElfSymbol symbol = _symbols[( int )relocation.Symbol];
uint symbolValue = symbol.Value;
// !!! This could be bogus
if (((rel.Info >> 8) & RelocationRelativeData) == RelocationRelativeData)
{
symbolValue += dataSection.Address;
}
else
{
symbolValue += baseAddress;
}
//if( addressBase.Address == 0 )
// symbolValue += baseAddress;
//else
// symbolValue += addressBase.Address;
uint value = ( uint )memory.ReadWord(( int )pointer);
//Debug.WriteLine( string.Format( " Relocation pointer 0x{0:X8} (elf {1:X8}), value {2:X8}, type {3}, existing memory value {4:X8}",
// pointer, relocation.Offset, symbolValue, relocation.RelocationType, value ) );
bool writeMemory = false;
switch (relocation.RelocationType)
{
case ElfRelocationType.None:
break;
case ElfRelocationType.Mips32:
value += symbolValue;
writeMemory = true;
break;
case ElfRelocationType.Mips26:
Debug.Assert(symbolValue % 4 == 0);
value = ( uint )((value & ~0x03FFFFFF) | ((value + (symbolValue >> 2)) & 0x03FFFFFF));
writeMemory = true;
break;
case ElfRelocationType.Hi16:
{
HiReloc hiReloc = new HiReloc();
hiReloc.Address = pointer;
hiReloc.Value = symbolValue;
hiRelocs.Add(hiReloc);
}
break;
case ElfRelocationType.Lo16:
{
uint vallo = ((value & 0x0000FFFF) ^ 0x00008000) - 0x00008000;
while (hiRelocs.Count > 0)
{
HiReloc hiReloc = hiRelocs[hiRelocs.Count - 1];
hiRelocs.RemoveAt(hiRelocs.Count - 1);
Debug.Assert(hiReloc.Value == symbolValue);
uint value2 = ( uint )memory.ReadWord(( int )hiReloc.Address);
uint temp = ((value2 & 0x0000FFFF) << 16) + vallo;
temp += symbolValue;
temp = ((temp >> 16) + (((temp & 0x00008000) != 0) ? ( uint )1 : ( uint )0)) & 0x0000FFFF;
value2 = ( uint )((value2 & ~0x0000FFFF) | temp);
//Debug.WriteLine( string.Format( " Updating memory at 0x{0:X8} to {1:X8} (from previous HI16)", hiReloc.Address, value2 ) );
memory.WriteWord(( int )hiReloc.Address, 4, ( int )value2);
}
value = ( uint )((value & ~0x0000FFFF) | ((symbolValue + vallo) & 0x0000FFFF));
}
writeMemory = true;
break;
default:
// Unsupported type
Debugger.Break();
break;
}
if (writeMemory == true)
{
//Debug.WriteLine( string.Format( " Updating memory at 0x{0:X8} to {1:X8}", pointer, value ) );
memory.WriteWord(( int )pointer, 4, ( int )value);
}
}
}