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
}
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];
}
