rose_addr_t
SgAsmElfSection::calculate_sizes(size_t r32size, size_t r64size, /*size of required parts*/
const std::vector<size_t> &optsizes, /*size of optional parts and number of parts parsed*/
size_t *entsize, size_t *required, size_t *optional, size_t *entcount) const
{
size_t struct_size = 0;
size_t extra_size = 0;
size_t entry_size = 0;
size_t nentries = 0;
SgAsmElfFileHeader *fhdr = get_elf_header();
/* Assume ELF Section Table Entry is correct for now for the size of each entry in the table. */
ROSE_ASSERT(get_section_entry()!=NULL);
entry_size = get_section_entry()->get_sh_entsize();
/* Size of required part of each entry */
if (0==r32size && 0==r64size) {
/* Probably called by four-argument SgAsmElfSection::calculate_sizes and we don't know the sizes of the required parts
* because there isn't a parser for this type of section, or the section doesn't contain a table. In the latter case
* the ELF Section Table has a zero sh_entsize and we'll treat the section as if it were a table with one huge entry.
* Otherwise we'll assume that the struct size is the same as the sh_entsize and there's no optional data. */
struct_size = entry_size>0 ? entry_size : get_size();
} else if (4==fhdr->get_word_size()) {
struct_size = r32size;
} else if (8==fhdr->get_word_size()) {
struct_size = r64size;
} else {
throw FormatError("bad ELF word size");
}
/* Entire entry should be at least large enough for the required part. This also takes care of the case when the ELF
* Section Table Entry has a zero-valued sh_entsize */
entry_size = std::max(entry_size, struct_size);
/* Size of optional parts. If we've parsed the table then use the largest optional part, otherwise assume the entry from
* the ELF Section Table is correct. */
nentries = optsizes.size();
if (nentries>0) {
for (size_t i=0; i<nentries; i++) {
extra_size = std::max(extra_size, optsizes[i]);
}
entry_size = std::min(entry_size, struct_size+extra_size);
} else {
extra_size = entry_size - struct_size;
nentries = entry_size>0 ? get_size() / entry_size : 0;
}
/* Return values */
if (entsize)
*entsize = entry_size;
if (required)
*required = struct_size;
if (optional)
*optional = extra_size;
if (entcount)
*entcount = nentries;
return entry_size * nentries;
}
/** Returns info about the size of the entries based on information already available. Any or all arguments may be null
* pointers if the caller is not interested in the value. */
rose_addr_t
SgAsmElfSectionTable::calculate_sizes(size_t *entsize, size_t *required, size_t *optional, size_t *entcount) const
{
SgAsmElfFileHeader *fhdr = dynamic_cast<SgAsmElfFileHeader*>(get_header());
ROSE_ASSERT(fhdr!=NULL);
size_t struct_size = 0;
size_t extra_size = fhdr->get_shextrasz();
size_t entry_size = 0;
size_t nentries = 0;
/* Size of required part of each entry */
if (4==fhdr->get_word_size()) {
struct_size = sizeof(SgAsmElfSectionTableEntry::Elf32SectionTableEntry_disk);
} else if (8==fhdr->get_word_size()) {
struct_size = sizeof(SgAsmElfSectionTableEntry::Elf64SectionTableEntry_disk);
} else {
throw FormatError("bad ELF word size");
}
/* Entire entry should be at least large enough for the required part. */
entry_size = struct_size;
/* Size of optional parts. If we've parsed the table then use the largest optional part, otherwise assume the entry from
* the ELF File Header is correct. */
SgAsmGenericSectionPtrList sections = fhdr->get_sections()->get_sections();
for (size_t i=0; i<sections.size(); i++) {
SgAsmElfSection *elfsec = dynamic_cast<SgAsmElfSection*>(sections[i]);
if (elfsec && elfsec->get_section_entry()) {
ROSE_ASSERT(elfsec->get_id()>=0);
nentries = std::max(nentries, (size_t)elfsec->get_id()+1);
extra_size = std::max(extra_size, elfsec->get_section_entry()->get_extra().size());
}
}
/* Total number of entries. Either we haven't parsed the section table yet (nor created the sections it defines) or we
* have. In the former case we use the setting from the ELF File Header. Otherwise the table has to be large enough to
* store the section with the largest ID (ID also serves as the index into the ELF Section Table). */
if (0==nentries)
nentries = fhdr->get_e_shnum();
/* Return values */
if (entsize)
*entsize = entry_size;
if (required)
*required = struct_size;
if (optional)
*optional = extra_size;
if (entcount)
*entcount = nentries;
return entry_size * nentries;
}
void
SgAsmElfRelocSection::unparse(std::ostream &f) const
{
SgAsmElfFileHeader *fhdr = get_elf_header();
ROSE_ASSERT(fhdr);
ByteOrder::Endianness sex = fhdr->get_sex();
size_t entry_size, struct_size, extra_size, nentries;
calculate_sizes(&entry_size, &struct_size, &extra_size, &nentries);
/* Adjust the entry size stored in the ELF Section Table */
get_section_entry()->set_sh_entsize(entry_size);
/* Write each entry's required part followed by the optional part */
for (size_t i=0; i<nentries; i++) {
SgAsmElfRelocEntry::Elf32RelaEntry_disk diska32;
SgAsmElfRelocEntry::Elf64RelaEntry_disk diska64;
SgAsmElfRelocEntry::Elf32RelEntry_disk disk32;
SgAsmElfRelocEntry::Elf64RelEntry_disk disk64;
void *disk = NULL;
SgAsmElfRelocEntry *entry = p_entries->get_entries()[i];
if (4==fhdr->get_word_size()) {
if (p_uses_addend) {
disk = entry->encode(sex, &diska32);
} else {
disk = entry->encode(sex, &disk32);
}
} else if (8==fhdr->get_word_size()) {
if (p_uses_addend) {
disk = entry->encode(sex, &diska64);
} else {
disk = entry->encode(sex, &disk64);
}
} else {
ROSE_ASSERT(!"unsupported word size");
}
rose_addr_t spos = i * entry_size;
spos = write(f, spos, struct_size, disk);
#if 0 /*FIXME: padding not supported here yet (RPM 2008-10-13)*/
if (entry->get_extra().size()>0) {
ROSE_ASSERT(entry->get_extra().size()<=extra_size);
write(f, spos, entry->get_extra());
}
#endif
}
unparse_holes(f);
}
/** Write the section table section back to disk */
void
SgAsmElfSectionTable::unparse(std::ostream &f) const
{
SgAsmElfFileHeader *fhdr = dynamic_cast<SgAsmElfFileHeader*>(get_header());
ROSE_ASSERT(fhdr!=NULL);
ByteOrder::Endianness sex = fhdr->get_sex();
SgAsmGenericSectionPtrList sections = fhdr->get_sectab_sections();
/* Write the sections first */
for (size_t i=0; i<sections.size(); i++)
sections[i]->unparse(f);
unparse_holes(f);
/* Calculate sizes. The ELF File Header should have been updated in reallocate() prior to unparsing. */
size_t ent_size, struct_size, opt_size, nentries;
calculate_sizes(&ent_size, &struct_size, &opt_size, &nentries);
ROSE_ASSERT(fhdr->get_shextrasz()==opt_size);
ROSE_ASSERT(fhdr->get_e_shnum()==nentries);
/* Write the section table entries */
for (size_t i=0; i<sections.size(); ++i) {
SgAsmElfSection *section = dynamic_cast<SgAsmElfSection*>(sections[i]);
ROSE_ASSERT(section!=NULL);
SgAsmElfSectionTableEntry *shdr = section->get_section_entry();
ROSE_ASSERT(shdr!=NULL);
ROSE_ASSERT(shdr->get_sh_offset()==section->get_offset());/*section table entry should have been updated in reallocate()*/
int id = section->get_id();
ROSE_ASSERT(id>=0 && (size_t)id<nentries);
SgAsmElfSectionTableEntry::Elf32SectionTableEntry_disk disk32;
SgAsmElfSectionTableEntry::Elf64SectionTableEntry_disk disk64;
void *disk = NULL;
if (4==fhdr->get_word_size()) {
disk = shdr->encode(sex, &disk32);
} else if (8==fhdr->get_word_size()) {
disk = shdr->encode(sex, &disk64);
} else {
ROSE_ASSERT(!"invalid word size");
}
/* The disk struct */
rose_addr_t spos = write(f, id*ent_size, struct_size, disk);
if (shdr->get_extra().size() > 0) {
ROSE_ASSERT(shdr->get_extra().size()<=opt_size);
write(f, spos, shdr->get_extra());
}
}
}
SgAsmElfRelocSection *
SgAsmElfRelocSection::parse()
{
SgAsmElfSection::parse();
SgAsmElfFileHeader *fhdr = get_elf_header();
ROSE_ASSERT(fhdr);
size_t entry_size, struct_size, extra_size, nentries;
calculate_sizes(&entry_size, &struct_size, &extra_size, &nentries);
ROSE_ASSERT(extra_size==0);
/* Parse each entry */
for (size_t i=0; i<nentries; i++) {
SgAsmElfRelocEntry *entry = 0;
if (4==fhdr->get_word_size()) {
if (p_uses_addend) {
SgAsmElfRelocEntry::Elf32RelaEntry_disk disk;
read_content_local(i*entry_size, &disk, struct_size);
entry = new SgAsmElfRelocEntry(this);
entry->parse(fhdr->get_sex(), &disk);
} else {
SgAsmElfRelocEntry::Elf32RelEntry_disk disk;
read_content_local(i*entry_size, &disk, struct_size);
entry = new SgAsmElfRelocEntry(this);
entry->parse(fhdr->get_sex(), &disk);
}
} else if (8==fhdr->get_word_size()) {
if (p_uses_addend) {
SgAsmElfRelocEntry::Elf64RelaEntry_disk disk;
read_content_local(i*entry_size, &disk, struct_size);
entry = new SgAsmElfRelocEntry(this);
entry->parse(fhdr->get_sex(), &disk);
} else {
SgAsmElfRelocEntry::Elf64RelEntry_disk disk;
read_content_local(i*entry_size, &disk, struct_size);
entry = new SgAsmElfRelocEntry(this);
entry->parse(fhdr->get_sex(), &disk);
}
} else {
throw FormatError("unsupported ELF word size");
}
if (extra_size>0)
entry->get_extra() = read_content_local_ucl(i*entry_size+struct_size, extra_size);
}
return this;
}
/** Write symbol table sections back to disk */
void
SgAsmElfSymbolSection::unparse(std::ostream &f) const
{
SgAsmElfFileHeader *fhdr = get_elf_header();
ROSE_ASSERT(fhdr);
ByteOrder sex = fhdr->get_sex();
size_t entry_size, struct_size, extra_size, nentries;
calculate_sizes(&entry_size, &struct_size, &extra_size, &nentries);
/* Adjust the entry size stored in the ELF Section Table */
get_section_entry()->set_sh_entsize(entry_size);
/* Write each entry's required part followed by the optional part */
for (size_t i=0; i<nentries; i++) {
SgAsmElfSymbol::Elf32SymbolEntry_disk disk32;
SgAsmElfSymbol::Elf64SymbolEntry_disk disk64;
void *disk=NULL;
SgAsmElfSymbol *entry = p_symbols->get_symbols()[i];
if (4==fhdr->get_word_size()) {
disk = entry->encode(sex, &disk32);
} else if (8==fhdr->get_word_size()) {
disk = entry->encode(sex, &disk64);
} else {
ROSE_ASSERT(!"unsupported word size");
}
rose_addr_t spos = i * entry_size;
spos = write(f, spos, struct_size, disk);
if (entry->get_extra().size()>0) {
ROSE_ASSERT(entry->get_extra().size()<=extra_size);
write(f, spos, entry->get_extra());
}
}
unparse_holes(f);
}
/** Initializes this ELF Symbol Section by parsing a file. */
SgAsmElfSymbolSection *
SgAsmElfSymbolSection::parse()
{
SgAsmElfSection::parse();
SgAsmElfFileHeader *fhdr = get_elf_header();
ROSE_ASSERT(fhdr!=NULL);
SgAsmElfSectionTableEntry *shdr = get_section_entry();
ROSE_ASSERT(shdr!=NULL);
SgAsmElfStringSection *strsec = dynamic_cast<SgAsmElfStringSection*>(get_linked_section());
ROSE_ASSERT(strsec!=NULL);
size_t entry_size, struct_size, extra_size, nentries;
calculate_sizes(&entry_size, &struct_size, &extra_size, &nentries);
ROSE_ASSERT(entry_size==shdr->get_sh_entsize());
/* Parse each entry */
for (size_t i=0; i<nentries; i++) {
SgAsmElfSymbol *entry=0;
if (4==fhdr->get_word_size()) {
entry = new SgAsmElfSymbol(this); /*adds symbol to this symbol table*/
SgAsmElfSymbol::Elf32SymbolEntry_disk disk;
read_content_local(i*entry_size, &disk, struct_size);
entry->parse(fhdr->get_sex(), &disk);
} else if (8==fhdr->get_word_size()) {
entry = new SgAsmElfSymbol(this); /*adds symbol to this symbol table*/
SgAsmElfSymbol::Elf64SymbolEntry_disk disk;
read_content_local(i*entry_size, &disk, struct_size);
entry->parse(fhdr->get_sex(), &disk);
} else {
throw FormatError("unsupported ELF word size");
}
if (extra_size>0)
entry->get_extra() = read_content_local_ucl(i*entry_size+struct_size, extra_size);
}
return this;
}
void
MyTraversal::visit(SgNode* astNode)
{
SgAsmElfFileHeader *fhdr = isSgAsmElfFileHeader(astNode);
if (fhdr) {
size_t oldsize = fhdr->get_word_size();
if (8==oldsize) {
size_t newsize = 4;
printf("*** Changing ELF word size from %zu bits to %zu bits\n", 8*oldsize, 8*newsize);
fhdr->get_exec_format()->set_word_size(newsize);
} else if (4==oldsize) {
size_t newsize = 8;
printf("*** Changing ELF word size from %zu bits to %zu bits\n", 8*oldsize, 8*newsize);
fhdr->get_exec_format()->set_word_size(newsize);
}
}
}
/** Parses an ELF Segment (Program Header) Table and constructs and parses all segments reachable from the table. The section
* is extended as necessary based on the number of entries and teh size of each entry. */
SgAsmElfSegmentTable *
SgAsmElfSegmentTable::parse()
{
SgAsmGenericSection::parse();
SgAsmElfFileHeader *fhdr = dynamic_cast<SgAsmElfFileHeader*>(get_header());
ROSE_ASSERT(fhdr!=NULL);
ByteOrder sex = fhdr->get_sex();
size_t ent_size, struct_size, opt_size, nentries;
calculate_sizes(&ent_size, &struct_size, &opt_size, &nentries);
ROSE_ASSERT(opt_size==fhdr->get_phextrasz() && nentries==fhdr->get_e_phnum());
/* If the current size is very small (0 or 1 byte) then we're coming straight from the constructor and the parsing should
* also extend this section to hold all the entries. Otherwise the caller must have assigned a specific size for a good
* reason and we should leave that alone, reading zeros if the entries extend beyond the defined size. */
if (get_size()<=1 && get_size()<nentries*ent_size)
extend(nentries*ent_size - get_size());
rose_addr_t offset=0; /* w.r.t. the beginning of this section */
for (size_t i=0; i<nentries; i++, offset+=ent_size) {
/* Read/decode the segment header */
SgAsmElfSegmentTableEntry *shdr = NULL;
if (4==fhdr->get_word_size()) {
SgAsmElfSegmentTableEntry::Elf32SegmentTableEntry_disk disk;
read_content_local(offset, &disk, struct_size);
shdr = new SgAsmElfSegmentTableEntry(sex, &disk);
} else {
SgAsmElfSegmentTableEntry::Elf64SegmentTableEntry_disk disk;
read_content_local(offset, &disk, struct_size);
shdr = new SgAsmElfSegmentTableEntry(sex, &disk);
}
shdr->set_index(i);
if (opt_size>0)
shdr->get_extra() = read_content_local_ucl(offset+struct_size, opt_size);
/* Null segments are just unused slots in the table; no real section to create */
if (SgAsmElfSegmentTableEntry::PT_NULL == shdr->get_type())
continue;
/* Create SgAsmElfSection objects for each ELF Segment. However, if the ELF Segment Table describes a segment
* that's the same offset and size as a section from the Elf Section Table (and the memory mappings are
* consistent) then use the preexisting section instead of creating a new one. */
SgAsmElfSection *s = NULL;
SgAsmGenericSectionPtrList possible = fhdr->get_file()->get_sections_by_offset(shdr->get_offset(), shdr->get_filesz());
for (size_t j=0; !s && j<possible.size(); j++) {
if (possible[j]->get_offset()!=shdr->get_offset() || possible[j]->get_size()!=shdr->get_filesz())
continue; /*different file extent*/
if (possible[j]->is_mapped()) {
if (possible[j]->get_mapped_preferred_rva()!=shdr->get_vaddr() ||
possible[j]->get_mapped_size()!=shdr->get_memsz())
continue; /*different mapped address or size*/
unsigned section_perms = (possible[j]->get_mapped_rperm() ? 0x01 : 0x00) |
(possible[j]->get_mapped_wperm() ? 0x02 : 0x00) |
(possible[j]->get_mapped_xperm() ? 0x04 : 0x00);
unsigned segment_perms = (shdr->get_flags() & SgAsmElfSegmentTableEntry::PF_RPERM ? 0x01 : 0x00) |
(shdr->get_flags() & SgAsmElfSegmentTableEntry::PF_WPERM ? 0x02 : 0x00) |
(shdr->get_flags() & SgAsmElfSegmentTableEntry::PF_XPERM ? 0x04 : 0x00);
if (section_perms != segment_perms)
continue; /*different mapped permissions*/
}
/* Found a match. Set memory mapping params only. */
s = dynamic_cast<SgAsmElfSection*>(possible[j]);
if (!s) continue; /*potential match was not from the ELF Section or Segment table*/
if (s->get_segment_entry()) continue; /*potential match is assigned to some other segment table entry*/
s->init_from_segment_table(shdr, true); /*true=>set memory mapping params only*/
}
/* Create a new segment if no matching section was found. */
if (!s) {
if (SgAsmElfSegmentTableEntry::PT_NOTE == shdr->get_type()) {
s = new SgAsmElfNoteSection(fhdr);
} else {
s = new SgAsmElfSection(fhdr);
}
s->init_from_segment_table(shdr);
s->parse();
}
}
return this;
}
/** Parses an ELF Section Table and constructs and parses all sections reachable from the table. The section is extended as
* necessary based on the number of entries and the size of each entry. */
SgAsmElfSectionTable *
SgAsmElfSectionTable::parse()
{
SgAsmGenericSection::parse();
SgAsmElfFileHeader *fhdr = dynamic_cast<SgAsmElfFileHeader*>(get_header());
ROSE_ASSERT(fhdr!=NULL);
ByteOrder::Endianness sex = fhdr->get_sex();
size_t ent_size, struct_size, opt_size, nentries;
calculate_sizes(&ent_size, &struct_size, &opt_size, &nentries);
ROSE_ASSERT(opt_size==fhdr->get_shextrasz() && nentries==fhdr->get_e_shnum());
/* If the current size is very small (0 or 1 byte) then we're coming straight from the constructor and the parsing should
* also extend this section to hold all the entries. Otherwise the caller must have assigned a specific size for a good
* reason and we should leave that alone, reading zeros if the entries extend beyond the defined size. */
if (get_size()<=1 && get_size()<nentries*ent_size)
extend(nentries*ent_size - get_size());
// Read all the section headers. Section headers are not essential to the Unix loader, which uses only segments. Therefore
// we should be prepared to handle bad entries.
std::vector<SgAsmElfSectionTableEntry*> entries;
rose_addr_t offset = 0;
try {
for (size_t i=0; i<nentries; i++, offset+=ent_size) {
SgAsmElfSectionTableEntry *shdr = NULL;
if (4 == fhdr->get_word_size()) {
SgAsmElfSectionTableEntry::Elf32SectionTableEntry_disk disk;
read_content_local(offset, &disk, struct_size);
shdr = new SgAsmElfSectionTableEntry(sex, &disk);
} else {
SgAsmElfSectionTableEntry::Elf64SectionTableEntry_disk disk;
read_content_local(offset, &disk, struct_size);
shdr = new SgAsmElfSectionTableEntry(sex, &disk);
}
if (opt_size>0)
shdr->get_extra() = read_content_local_ucl(offset+struct_size, opt_size);
entries.push_back(shdr);
}
} catch (const ShortRead &error) {
mlog[ERROR] <<"short read for elf section header #" <<entries.size()
<<" at file offset " <<StringUtility::addrToString(error.offset)
<<" when reading " <<StringUtility::plural(error.size, "bytes") <<"\n";
mlog[ERROR] <<"expected " <<StringUtility::plural(nentries, "sections") <<", but bailing out early\n";
nentries = entries.size();
}
/* This vector keeps track of which sections have already been parsed. We could get the same information by calling
* fhdr->get_section_by_id() and passing the entry number since entry numbers and IDs are one and the same in ELF. However,
* this is a bit easier. */
std::vector<SgAsmElfSection*> is_parsed;
is_parsed.resize(entries.size(), NULL);
/* All sections implicitly depend on the section string table for their names. */
SgAsmElfStringSection *section_name_strings=NULL;
if (fhdr->get_e_shstrndx() > 0 && fhdr->get_e_shstrndx() < entries.size()) {
SgAsmElfSectionTableEntry *entry = entries[fhdr->get_e_shstrndx()];
ASSERT_not_null(entry);
section_name_strings = new SgAsmElfStringSection(fhdr);
section_name_strings->init_from_section_table(entry, section_name_strings, fhdr->get_e_shstrndx());
section_name_strings->parse();
is_parsed[fhdr->get_e_shstrndx()] = section_name_strings;
}
/* Read all the sections. Some sections depend on other sections, so we read them in such an order that all dependencies
* are satisfied first. */
while (1) {
bool try_again=false;
for (size_t i=0; i<entries.size(); i++) {
SgAsmElfSectionTableEntry *entry = entries[i];
ROSE_ASSERT(entry->get_sh_link()<entries.size());
/* Some sections might reference another section through the sh_link member. */
bool need_linked = entry->get_sh_link() > 0;
ROSE_ASSERT(!need_linked || entry->get_sh_link()<entries.size());
SgAsmElfSection *linked = need_linked ? is_parsed[entry->get_sh_link()] : NULL;
/* Relocation sections might have a second linked section stored in sh_info. */
bool need_info_linked = (entry->get_sh_type() == SgAsmElfSectionTableEntry::SHT_REL ||
entry->get_sh_type() == SgAsmElfSectionTableEntry::SHT_RELA) &&
entry->get_sh_info() > 0;
ROSE_ASSERT(!need_info_linked || entry->get_sh_info()<entries.size());
SgAsmElfSection *info_linked = need_info_linked ? is_parsed[entry->get_sh_info()] : NULL;
if (is_parsed[i]) {
/* This section has already been parsed. */
} else if ((need_linked && !linked) || (need_info_linked && !info_linked)) {
/* Don't parse this section yet because it depends on something that's not parsed yet. */
try_again = true;
} else {
switch (entry->get_sh_type()) {
case SgAsmElfSectionTableEntry::SHT_NULL:
/* Null entry. We still create the section just to hold the section header. */
is_parsed[i] = new SgAsmElfSection(fhdr);
break;
case SgAsmElfSectionTableEntry::SHT_NOBITS:
/* These types of sections don't occupy any file space (e.g., BSS) */
is_parsed[i] = new SgAsmElfSection(fhdr);
break;
case SgAsmElfSectionTableEntry::SHT_DYNAMIC: {
SgAsmElfStringSection *strsec = dynamic_cast<SgAsmElfStringSection*>(linked);
ROSE_ASSERT(strsec);
is_parsed[i] = new SgAsmElfDynamicSection(fhdr, strsec);
break;
}
case SgAsmElfSectionTableEntry::SHT_DYNSYM: {
SgAsmElfStringSection *strsec = dynamic_cast<SgAsmElfStringSection*>(linked);
ROSE_ASSERT(strsec);
SgAsmElfSymbolSection *symsec = new SgAsmElfSymbolSection(fhdr, strsec);
symsec->set_is_dynamic(true);
is_parsed[i] = symsec;
break;
}
case SgAsmElfSectionTableEntry::SHT_SYMTAB: {
SgAsmElfStringSection *strsec = dynamic_cast<SgAsmElfStringSection*>(linked);
ROSE_ASSERT(strsec);
SgAsmElfSymbolSection *symsec = new SgAsmElfSymbolSection(fhdr, strsec);
symsec->set_is_dynamic(false);
is_parsed[i] = symsec;
break;
}
case SgAsmElfSectionTableEntry::SHT_STRTAB:
is_parsed[i] = new SgAsmElfStringSection(fhdr);
break;
case SgAsmElfSectionTableEntry::SHT_REL: {
SgAsmElfSymbolSection *symbols = dynamic_cast<SgAsmElfSymbolSection*>(linked);
SgAsmElfRelocSection *relocsec = new SgAsmElfRelocSection(fhdr, symbols, info_linked);
relocsec->set_uses_addend(false);
is_parsed[i] = relocsec;
break;
}
case SgAsmElfSectionTableEntry::SHT_RELA: {
SgAsmElfSymbolSection *symbols = dynamic_cast<SgAsmElfSymbolSection*>(linked);
SgAsmElfRelocSection *relocsec = new SgAsmElfRelocSection(fhdr, symbols, info_linked);
relocsec->set_uses_addend(true);
is_parsed[i] = relocsec;
break;
}
case SgAsmElfSectionTableEntry::SHT_PROGBITS: {
if (!section_name_strings) {
fprintf(stderr, "SgAsmElfSectionTable::parse(): no string table for section table\n");
is_parsed[i] = new SgAsmElfSection(fhdr);
} else {
std::string section_name = section_name_strings->read_content_local_str(entry->get_sh_name());
if (section_name == ".eh_frame") {
is_parsed[i] = new SgAsmElfEHFrameSection(fhdr);
} else {
is_parsed[i] = new SgAsmElfSection(fhdr);
}
}
break;
}
case SgAsmElfSectionTableEntry::SHT_GNU_versym: {
is_parsed[i] = new SgAsmElfSymverSection(fhdr);
break;
}
case SgAsmElfSectionTableEntry::SHT_GNU_verdef: {
SgAsmElfStringSection *strsec = dynamic_cast<SgAsmElfStringSection*>(linked);
ROSE_ASSERT(strsec);
is_parsed[i] = new SgAsmElfSymverDefinedSection(fhdr,strsec);
break;
}
case SgAsmElfSectionTableEntry::SHT_GNU_verneed: {
SgAsmElfStringSection *strsec = dynamic_cast<SgAsmElfStringSection*>(linked);
ROSE_ASSERT(strsec);
is_parsed[i] = new SgAsmElfSymverNeededSection(fhdr,strsec);
break;
}
default:
is_parsed[i] = new SgAsmElfSection(fhdr);
break;
}
is_parsed[i]->init_from_section_table(entry, section_name_strings, i);
is_parsed[i]->parse();
}
}
if (!try_again)
break;
}
/* Initialize links between sections */
for (size_t i = 0; i < entries.size(); i++) {
SgAsmElfSectionTableEntry *shdr = entries[i];
if (shdr->get_sh_link() > 0) {
SgAsmElfSection *source = isSgAsmElfSection(fhdr->get_file()->get_section_by_id(i));
SgAsmElfSection *target = isSgAsmElfSection(fhdr->get_file()->get_section_by_id(shdr->get_sh_link()));
assert(source); /* because we created it above */
source->set_linked_section(target);
}
}
/* Finish parsing sections now that we have basic info for all the sections. */
for (size_t i=0; i<is_parsed.size(); i++)
is_parsed[i]->finish_parsing();
return this;
}
/** Unparse one Common Information Entry (CIE) without unparsing the Frame Description Entries (FDE) to which it points. The
* initial length fields are not included in the result string. */
std::string
SgAsmElfEHFrameEntryCI::unparse(const SgAsmElfEHFrameSection *ehframe) const
{
SgAsmElfFileHeader *fhdr = ehframe->get_elf_header();
ROSE_ASSERT(fhdr!=NULL);
/* Allocate worst-case size for results */
size_t worst_size = (4+
1+
get_augmentation_string().size()+1+
10+
10+
10+
get_augmentation_data_length()+
get_instructions().size()+
fhdr->get_word_size());
unsigned char *buf = new unsigned char[worst_size];
rose_addr_t at = 0;
uint32_t u32_disk;
unsigned char u8_disk;
/* CIE back offset (always zero) */
u32_disk=0;
memcpy(buf+at, &u32_disk, 4); at+=4;
/* Version */
u8_disk = get_version();
memcpy(buf+at, &u8_disk, 1); at+=1;
/* NUL-terminated Augmentation String */
size_t sz = get_augmentation_string().size()+1;
memcpy(buf+at, get_augmentation_string().c_str(), sz); at+=sz;
/* Alignment factors */
at = ehframe->write_uleb128(buf, at, get_code_alignment_factor());
at = ehframe->write_sleb128(buf, at, get_data_alignment_factor());
/* Augmentation data */
at = ehframe->write_uleb128(buf, at, get_augmentation_data_length());
std::string astr = get_augmentation_string();
if (!astr.empty() && astr[0]=='z') {
for (size_t i=1; i<astr.size(); i++) {
if ('L'==astr[i]) {
u8_disk = get_lsda_encoding();
buf[at++] = u8_disk;
} else if ('P'==astr[i]) {
u8_disk = get_prh_encoding();
buf[at++] = u8_disk;
switch (get_prh_encoding()) {
case 0x05:
case 0x06:
case 0x07:
buf[at++] = get_prh_arg();
ByteOrder::host_to_le(get_prh_addr(), &u32_disk);
memcpy(buf+at, &u32_disk, 4); at+=4;
break;
default:
/* See parser */
if (++nwarnings<=WARNING_LIMIT) {
fprintf(stderr, "%s:%u: warning: unknown PRH encoding (0x%02x)\n",
__FILE__, __LINE__, get_prh_encoding());
if (WARNING_LIMIT==nwarnings)
fprintf(stderr, " (additional frame warnings will be suppressed)\n");
}
break;
}
} else if ('R'==astr[i]) {
u8_disk = get_addr_encoding();
buf[at++] = u8_disk;
} else if ('S'==astr[i]) {
/* Signal frame; no auxilliary data */
} else {
ROSE_ASSERT(!"invalid .eh_frame augmentation string");
abort();
}
}
}
/* Initial instructions */
sz = get_instructions().size();
if (sz>0) {
memcpy(buf+at, &(get_instructions()[0]), sz);
at += sz;
}
std::string retval((char*)buf, at);
delete[] buf;
return retval;
}
/** Unparse the Frame Description Entry (FDE) into a string but do not include the leading length field(s) or the CIE back
* pointer. */
std::string
SgAsmElfEHFrameEntryFD::unparse(const SgAsmElfEHFrameSection *ehframe, SgAsmElfEHFrameEntryCI *cie) const
{
SgAsmElfFileHeader *fhdr = ehframe->get_elf_header();
ROSE_ASSERT(fhdr!=NULL);
/* Allocate worst-case size for results */
size_t worst_size = 8 + get_augmentation_data().size() + get_instructions().size() + fhdr->get_word_size();
unsigned char *buf = new unsigned char[worst_size];
size_t sz;
rose_addr_t at = 0;
uint32_t u32_disk;
/* PC Begin (begin_rva) and size */
switch (cie->get_addr_encoding()) {
case -1: /* No address encoding specified */
case 0x01:
case 0x03:
case 0x1b: {
ByteOrder::host_to_le(get_begin_rva().get_rva(), &u32_disk);
memcpy(buf+at, &u32_disk, 4); at+=4;
ByteOrder::host_to_le(get_size(), &u32_disk);
memcpy(buf+at, &u32_disk, 4); at+=4;
break;
}
default:
/* See parser */
if (++nwarnings<=WARNING_LIMIT) {
fprintf(stderr, "%s:%u: warning: unknown FDE address encoding (0x%02x)\n",
__FILE__, __LINE__, cie->get_addr_encoding());
if (WARNING_LIMIT==nwarnings)
fprintf(stderr, " (additional frame warnings will be suppressed)\n");
}
break;
}
/* Augmentation Data */
std::string astr = cie->get_augmentation_string();
if (astr.size()>0 && astr[0]=='z') {
at = ehframe->write_uleb128(buf, at, get_augmentation_data().size());
sz = get_augmentation_data().size();
if (sz>0) {
memcpy(buf+at, &(get_augmentation_data()[0]), sz);
at += sz;
}
}
/* Call frame instructions */
sz = get_instructions().size();
if (sz>0) {
memcpy(buf+at, &(get_instructions()[0]), sz);
at += sz;
}
std::string retval((char*)buf, at);
delete[] buf;
return retval;
}
