void CELF2ELF<ELFSTRUCTURES>::MakeSymbolTable() { uint32 SectionNumber; // Section number char * SectionName; // Section name uint32 SecNamei; // Section name index uint32 OldSymi; // Old symbol index uint32 NewSymi; // New symbol index int isymt; // 0 = symtab, 1 = dynsym const char * name1; // Old name of symbol const char * name2; // Changed name of symbol int SymbolType; // Symbol type for cmd.SymbolChange int action; // Symbol change action int binding; // Symbol binding TELF_Symbol sym; // Symbol table entry TELF_Symbol AliasEntry; // Symbol table alias entry uint32 symnamei; // New symbol name index CMemoryBuffer TempGlobalSymbolTable; // Temporary storage of public and external symbols // Find symbol table and string tables for (SectionNumber = 0; SectionNumber < this->NSections; SectionNumber++) { // Get copy of 32-bit header or converted 64-bit header TELF_SectionHeader sheader = this->SectionHeaders[SectionNumber]; switch (sheader.sh_type) { case SHT_SYMTAB: isymtab[0] = SectionNumber; // Symbol table found istrtab[0] = this->SectionHeaders[SectionNumber].sh_link; // Associated string table break; case SHT_DYNSYM: isymtab[1] = SectionNumber; // Dynamic symbol table found istrtab[1] = this->SectionHeaders[SectionNumber].sh_link; // Associated string table break; case SHT_STRTAB: SecNamei = sheader.sh_name; if (SecNamei >= this->SecStringTableLen) err.submit(2112); SectionName = this->SecStringTable + SecNamei; if (SectionNumber == this->FileHeader.e_shstrndx || !strcmp(SectionName,".shstrtab")) { istrtab[2] = SectionNumber; // Section header string table found } else if (!strcmp(SectionName,".strtab") && !istrtab[0]) { istrtab[0] = SectionNumber; // Symbol string table found } else if (!strcmp(SectionName,".stabstr")) { istrtab[3] = SectionNumber; // Debug string table found } break; } } // Make new symbol tables and string tables // Loop through possibly two symbol tables for (isymt = 0; isymt < 2; isymt++) { if (isymtab[isymt] && isymtab[isymt] < this->NSections && istrtab[isymt] && istrtab[isymt] < this->NSections) { // Symbol table header uint32 SymTabHeaderOffset = uint32(this->FileHeader.e_shoff + isymtab[isymt] * this->SectionHeaderSize); //TELF_SectionHeader SymTabHeader = this->Get<TELF_SectionHeader>(SymTabHeaderOffset); // Some compilers fail with the double template here. Avoid the template: TELF_SectionHeader SymTabHeader = *(TELF_SectionHeader*)(this->Buf() + SymTabHeaderOffset); // Find symbol table uint32 symtabsize = (uint32)(SymTabHeader.sh_size); int8 * symtab = this->Buf() + SymTabHeader.sh_offset; int8 * symtabend = symtab + symtabsize; int entrysize = (int)(SymTabHeader.sh_entsize); if (entrysize <= 0) entrysize = sizeof(TELF_Symbol); // Find string table char * StringTable = this->Buf() + this->SectionHeaders[istrtab[isymt]].sh_offset; uint32 StringTableLen = uint32(this->SectionHeaders[istrtab[isymt]].sh_size); NewStringTable[isymt].Push(0, 1); // Initialize new string table, first entry 0 if (isymt == 0) { // Allocate NewSymbolIndex NumOldSymbols = (symtabsize + entrysize - 1) / entrysize; // round up to nearest integer to be safe NewSymbolIndex.SetNum(NumOldSymbols); // Allocate array NewSymbolIndex.SetZero(); // Initialize } // Loop through old symbol table for (OldSymi = 0; symtab < symtabend; symtab += entrysize, OldSymi++) { // Symbol table entry sym = *(TELF_Symbol*)symtab; // Symbol name if (sym.st_name < StringTableLen) { name1 = StringTable + sym.st_name;} else { err.submit(2035); name1 = 0; } name2 = 0; // Symbol type int type = sym.st_type; binding = sym.st_bind; if (binding == STB_LOCAL) { SymbolType = SYMT_LOCAL; // Symbol is local } else if (type == STT_OBJECT || type == STT_FUNC || type == STT_NOTYPE) { if (int16(sym.st_shndx) > 0) { // Check section number SymbolType = SYMT_PUBLIC; // Symbol is public } else { SymbolType = SYMT_EXTERNAL; // Symbol is external } } else { SymbolType = SYMT_OTHER; // Symbol is section or filename or debug } // Check if any change required for this symbol action = cmd.SymbolChange(name1, &name2, SymbolType); switch (action) { case SYMA_NOCHANGE: // No change break; case SYMA_MAKE_WEAK: // Make symbol weak if (cmd.OutputType == FILETYPE_COFF) { // PE/COFF format does not support weak publics. Use this only when converting to ELF err.submit(2200); } // Make weak binding = STB_WEAK; sym.st_bind = binding; sym.st_type = type ; break; case SYMA_MAKE_LOCAL: // Make public symbol local, make external symbol ignored binding = STB_LOCAL; SymbolType = SYMT_LOCAL; sym.st_bind = binding; sym.st_type = type ; break; case SYMA_CHANGE_NAME: // Change name of symbol name1 = name2; name2 = 0; break; case SYMA_CHANGE_ALIAS: // Make alias and keep old name if (isymt != 0) err.submit(1033, name1); // alias in dynsym not supported yet AliasEntry = sym; break; default: err.submit(9000); // unknown error } // Add entry to new string table if (name1 && *name1) { symnamei = NewStringTable[isymt].PushString(name1); } else { symnamei = 0; } sym.st_name = symnamei; if (isymt == 0) { // The symtab symbol table must be ordered with local symbols first. // Therefore the public and external symbols are temporarily stored // in TempGlobalSymbolTable and the high bit of NewSymi is set. // The two tables are joined together when the number of local symbols // is known and the indexes into TempGlobalSymbolTable are adjusted // to indexes into the joined table. if (SymbolType == SYMT_LOCAL) { NewSymbolTable[isymt].Push(&sym, entrysize); NewSymi = NewSymbolTable[isymt].GetLastIndex(); } else { TempGlobalSymbolTable.Push(&sym, entrysize); NewSymi = TempGlobalSymbolTable.GetLastIndex() | 0x80000000; } // Insert into symbol index translation table NewSymbolIndex[OldSymi] = NewSymi; if (action == SYMA_CHANGE_ALIAS && name2 && *name2) { // Make one more entry for new alias symnamei = NewStringTable[isymt].PushString(name2); AliasEntry.st_name = symnamei; TempGlobalSymbolTable.Push(&AliasEntry, entrysize); } } else { // dynsym table has no local symbols // no index translation table is currently needed NewSymbolTable[isymt].Push(&sym, entrysize); } } // End of loop through old symbol table if (isymt == 0) { // The symbol table has been temporarily split into local and non-local // Save index to first nonlocal symbol FirstGlobalSymbol = NewSymbolTable[isymt].GetNumEntries(); // Adjust symbol index translation table for (OldSymi = 0; OldSymi < NumOldSymbols; OldSymi++) { if (NewSymbolIndex[OldSymi] & 0x80000000) { // Translate index into TempGlobalSymbolTable to index into joined table NewSymbolIndex[OldSymi] = (NewSymbolIndex[OldSymi] & ~0x80000000) + FirstGlobalSymbol; } } // Join the two tables NewSymbolTable[isymt].Push(TempGlobalSymbolTable.Buf(), TempGlobalSymbolTable.GetDataSize()); } } } // End of isymt loop through possibly two symbol tables }
// MakeSegmentList void COMF2ASM::MakeSegmentList() { // Make Sections list in Disasm int32 SegNum; // Segment number int32 Segment; // Segment number in OMF record uint32 RecNum; // OMF record number uint32 LastDataRecord; // OMF record number of last LEDATA record uint32 RecOffset; // Segment offset of LEDATA, LIDATA record uint32 RecSize; // Data size of LEDATA, LIDATA record uint32 LastDataRecordSize; // Last RecSize uint32 LastOffset; // Last RecOffset int8 * LastDataRecordPointer; // Point to last raw data uint32 BufOffset; // Offset of segment into SegmentData buffer CMemoryBuffer TempBuf; // Temporary buffer for building raw data // Loop through segments for (SegNum = 1; SegNum <= NumSegments; SegNum++) { // Get size uint32 SegmentSize = Segments[SegNum].Size; if (SegmentSize == 0) continue; // Empty segment // Allocate temporary data buffer and reset it TempBuf.SetSize(SegmentSize + 16); int FillByte = 0; // Byte to fill memory with if (Segments[SegNum].Type == 1) { // Code segment. Fill any unused bytes with NOP opcode = 0x90 FillByte = 0x90; } memset(TempBuf.Buf(), FillByte, SegmentSize + 16);// Reset to all 0 or NOP LastDataRecord = 0; LastDataRecordSize = 0; LastDataRecordPointer = 0; LastOffset = 0; int comdatsSoFar = 0; // Search for LEDATA, LIDATA and FIXUPP records for this segment for (RecNum = 0; RecNum < NumRecords; RecNum++) { if (Records[RecNum].Type2 == OMF_LEDATA) { // LEDATA record Records[RecNum].Index = 3; // Initialize record reading Segment = Records[RecNum].GetIndex();// Read segment number if ((Segment & 0xC000) == 0x4000) { // Refers to Borland communal section Segment = (Segment & ~0x4000) + FirstComDatSection - 1; } if (Segment != SegNum) continue; // Does not refer to this segment RecOffset = Records[RecNum].GetNumeric();// Read offset of this record RecSize = Records[RecNum].End - Records[RecNum].Index; // Calculate size of data LastDataRecord = RecNum; // Save for later FIXUPP that refers to this record if (RecOffset < LastOffset + LastDataRecordSize && LastOffset < RecOffset + RecSize) { // Overlapping data records if (RecOffset + 8 < LastOffset + LastDataRecordSize || Segments[SegNum].Type != 1) { // Overlapping data by more than 7 bytes or not executable code err.submit(1207); } else { // Possibly backpatched code err.submit(1208); // Warning err.ClearError(1208); // Report only once } } LastDataRecordSize = RecSize; LastDataRecordPointer = Records[RecNum].buffer + Records[RecNum].FileOffset + Records[RecNum].Index; LastOffset = RecOffset; // Save offset for subsequent FIXUPP records // Check if data within segment if (RecOffset + RecSize > SegmentSize) { err.submit(2309, GetSegmentName(Segment)); continue; } // Put raw data into temporary buffer memcpy(TempBuf.Buf() + RecOffset, LastDataRecordPointer, RecSize); } // Finished with LEDATA record if (Records[RecNum].Type2 == OMF_LIDATA) { // LIDATA record Records[RecNum].Index = 3; // Initialize record reading Segment = Records[RecNum].GetIndex(); if (Segment != SegNum) continue; // Does not refer to this segment LastDataRecord = RecNum; // Save for later FIXUPP that refers to this record RecOffset = Records[RecNum].GetNumeric();// Read offset if (RecOffset > SegmentSize) { err.submit(2310); continue; // Error: outside bounds } // Unpack LIDATA blocks recursively RecSize = Records[RecNum].UnpackLIDATABlock(TempBuf.Buf() + RecOffset, SegmentSize - RecOffset); if (RecOffset < LastOffset + LastDataRecordSize && LastOffset < RecOffset + RecSize) { // Overlapping data records err.submit(1207); // Warning } LastDataRecordSize = RecSize; // Save data size LastOffset = RecOffset; // Save offset for subsequent FIXUPP records } // Finished with LIDATA record if (Records[RecNum].Type2 == OMF_COMDAT) { // COMDAT record. Records[RecNum].Index = 3; // Initialize record reading uint16 flags = Records[RecNum].GetByte(); if ((flags&1)==0) { // not a continuation ++comdatsSoFar; LastDataRecord = RecNum; // Save for later FIXUPP that refers to this record } Segment = FirstComDatSection + comdatsSoFar-1; if (SegNum != Segment) continue; uint16 attribs = Records[RecNum].GetByte(); Records[RecNum].GetByte(); // align (ignore) RecOffset = Records[RecNum].GetNumeric(); Records[RecNum].GetIndex(); // type (ignore) if ((attribs&0xF)==0) { Records[RecNum].GetIndex(); // public base uint16 publicSegment = Records[RecNum].GetIndex(); if (publicSegment==0) Records[RecNum].GetIndex(); // public frame (ignore) } Records[RecNum].GetIndex(); // public name (ignore) RecSize = Records[RecNum].End - Records[RecNum].Index; // Calculate size of data LastDataRecord = RecNum; // Save for later FIXUPP that refers to this record LastDataRecordSize = RecSize; LastDataRecordPointer = Records[RecNum].buffer + Records[RecNum].Index+Records[RecNum].FileOffset; LastOffset = RecOffset; // Put raw data into temporary buffer memcpy(TempBuf.Buf() + RecOffset, LastDataRecordPointer, RecSize); } // Finished with COMDAT record if (Records[RecNum].Type2 == OMF_FIXUPP) { // FIXUPP record if (Segment != SegNum) continue; // Does not refer to this segment Records[RecNum].Index = 3; if (Records[LastDataRecord].Type2 == OMF_LEDATA) { // FIXUPP for last LEDATA record // Make relocation records MakeRelocations(Segment, RecNum, LastOffset, LastDataRecordSize, (uint8*)TempBuf.Buf()); } else if (Records[RecNum].Index < Records[RecNum].End) { // Non-empty FIXUPP record does not refer to LEDATA record if (Records[LastDataRecord].Type2 == OMF_COMDAT) { // FIXUPP for last COMDAT record // Make relocation records MakeRelocations(Segment, RecNum, LastOffset, LastDataRecordSize, (uint8*)TempBuf.Buf()); } else if (Records[LastDataRecord].Type2 == OMF_LIDATA) { err.submit(2311); // Error: Relocation of iterated data not supported } else { err.submit(2312); // Does not refer to data record } } } } // End of loop to search for LEDATA, LIDATA and FIXUPP records for this segment // Transfer raw data from TempBuf to SegmentData buffer BufOffset = SegmentData.Push(TempBuf.Buf(), SegmentSize); // Remember offset into SegmentData Segments[SegNum].BufOffset = BufOffset; } // End of first loop through segments // We must put all segments into SegmentData buffer before we assign pointers to // the raw data because otherwise the SegmentData buffer might me reallocated // when it grows and the pointers become invalid. This is the reasons why we // have two loops through the segments here. // Second loop through segments int totalcodesize=0; for (SegNum = 1; SegNum <= NumSegments; SegNum++) { // Pointer to merged raw data uint8 * RawDatap = (uint8*)SegmentData.Buf() + Segments[SegNum].BufOffset; // Size of raw data uint32 InitSize = (Segments[SegNum].Type == 3) ? 0 : Segments[SegNum].Size; // Define segment const char * SegmentName = NameBuffer.Buf() + Segments[SegNum].NameO; Disasm.AddSection(RawDatap, InitSize, Segments[SegNum].Size, Segments[SegNum].Offset, Segments[SegNum].Type, Segments[SegNum].Align, Segments[SegNum].WordSize, SegmentName); if (Segments[SegNum].Type == 1 || Segments[SegNum].Type == 0x1001) { totalcodesize += Segments[SegNum].Size; } } }
void CELF2ELF<ELFSTRUCTURES>::MakeBinaryFile() { uint32 SectionNumber; // Section number CMemoryBuffer NewSectionHeaders; // Temporary storage of section headers // Copy file header ToFile.Push(this->Buf(), sizeof(TELF_Header)); // Copy program header if any if (this->FileHeader.e_phnum) { ToFile.Push(this->Buf() + this->FileHeader.e_phoff, this->FileHeader.e_phentsize * this->FileHeader.e_phnum); ((TELF_Header*)ToFile.Buf())->e_phoff = sizeof(TELF_Header); } // Copy section data uint32 SectionHeaderOffset = uint32(this->FileHeader.e_shoff); TELF_SectionHeader sheader; // Section header // Loop through sections for (SectionNumber = 0; SectionNumber < this->NSections; SectionNumber++, SectionHeaderOffset += this->FileHeader.e_shentsize) { // Get section header //sheader = this->Get<TELF_SectionHeader>(SectionHeaderOffset); // Some compilers fail with the double template here. Avoid the template: sheader = *(TELF_SectionHeader*)(this->Buf() + SectionHeaderOffset); // Check for null section if (SectionNumber == 0 && sheader.sh_type != 0) { // First section must be null err.submit(2036, 0); } // Align ToFile.Align(16); // Check for sections that have been modified if (SectionNumber == isymtab[0]) { // Static symbol table .symtab sheader.sh_offset = ToFile.Push(NewSymbolTable[0].Buf(), NewSymbolTable[0].GetDataSize()); sheader.sh_size = NewSymbolTable[0].GetDataSize(); sheader.sh_info = FirstGlobalSymbol; } else if (SectionNumber == isymtab[1]) { // Dynamic symbol table .dynsym sheader.sh_offset = ToFile.Push(NewSymbolTable[1].Buf(), NewSymbolTable[1].GetDataSize()); sheader.sh_size = NewSymbolTable[1].GetDataSize(); } else if (SectionNumber == istrtab[0]) { // Symbol string table .strtab sheader.sh_offset = ToFile.Push(NewStringTable[0].Buf(), NewStringTable[0].GetDataSize()); sheader.sh_size = NewStringTable[0].GetDataSize(); } else if (SectionNumber == istrtab[1] && SectionNumber != istrtab[0]) { // Dynamic symbol string table if different from .strtab sheader.sh_offset = ToFile.Push(NewStringTable[1].Buf(), NewStringTable[1].GetDataSize()); sheader.sh_size = NewStringTable[1].GetDataSize(); } else if (SectionNumber == istrtab[2]) { // Section name string table .shstrtab sheader.sh_offset = ToFile.Push(NewStringTable[2].Buf(), NewStringTable[2].GetDataSize()); sheader.sh_size = NewStringTable[2].GetDataSize(); } else { // Any other section (including istrtab[3] = .stabstr) sheader.sh_offset = ToFile.Push(this->Buf() + (uint32)sheader.sh_offset, (uint32)sheader.sh_size); } // Store section header NewSectionHeaders.Push(&sheader, sizeof(sheader)); } // End of section loop // Align ToFile.Align(16); // Store section headers uint32 SectionHeadersOffset = ToFile.Push(NewSectionHeaders.Buf(), NewSectionHeaders.GetDataSize()); // Update file header ((TELF_Header*)ToFile.Buf())->e_shoff = SectionHeadersOffset; ((TELF_Header*)ToFile.Buf())->e_shentsize = sizeof(TELF_SectionHeader); ((TELF_Header*)ToFile.Buf())->e_shnum = NewSectionHeaders.GetNumEntries(); ((TELF_Header*)ToFile.Buf())->e_shstrndx = istrtab[2]; }