// Returns a fake asm_program_t for use when disassembling bits out of memory
asm_program_t* fake_prog_for_arch(enum bfd_architecture arch)
{
int machine = 0; // TODO: pick based on arch
asm_program_t *prog = new asm_program_t;
prog->abfd = bfd_openw("/dev/null", NULL);
assert(prog->abfd);
bfd_set_arch_info(prog->abfd, bfd_lookup_arch(arch, machine));
//not in .h bfd_default_set_arch_mach(prog->abfd, arch, machine);
bfd_set_arch_info(prog->abfd, bfd_lookup_arch(arch, machine));
init_disasm_info(prog);
return prog;
}
static void
initialize_sections(asm_program_t *prog, bfd_vma base)
{
bfd_vma offset = 0;
struct disassemble_info *disasm_info = &prog->disasm_info;
assert(prog);
bfd *abfd = prog->abfd;
unsigned int opb = bfd_octets_per_byte(abfd);
disasm_info->octets_per_byte = opb;
init_disasm_info(prog);
section_t **nextseg = &prog->segs;
asection *section;
/* Set to NULL in case there are zero segments. */
*nextseg = NULL;
/* Look for the section loaded into the lowest memory address */
if (base != -1) {
offset = base - asmir_get_base_address(prog);
//fprintf(stderr, "Adjusting by %Lx\n", offset);
}
for(section = abfd->sections; section; section = section->next) {
section_t *seg;
bfd_byte *data;
bfd_vma datasize = bfd_get_section_size_before_reloc(section);
if(datasize == 0) continue;
section->vma += offset;
data = bfd_alloc2(abfd, datasize, sizeof(bfd_byte));
bfd_get_section_contents(abfd, section, data, 0, datasize);
seg = bfd_alloc(abfd, sizeof(section_t));
seg->data = data;
seg->datasize = datasize;
seg->start_addr = section->vma;
seg->end_addr = section->vma + datasize/opb;
seg->section = section;
seg->is_code = !!(section->flags & SEC_CODE);
seg->next = NULL;
*nextseg = seg;
nextseg = &seg->next;
}
}
/* initialize bincode */
bincode_t *initialize_bincode(const char *file)
{
bfd *abfd;
bincode_t *bin;
//char *target = "x86_64-unknown-linux-gnu";
char *target = "i686-pc-linux-gnu";
bfd_init();
if (!bfd_set_default_target(target)) {
bs_dbgmsg(" (!) bfd_set_default_target()\n");
return NULL;
}
if ((abfd = bfd_openr(file, target)) == NULL) {
bs_dbgmsg(" (!) bfd_openr(): %s\n", file);
return NULL;
}
if (!bfd_check_format(abfd, bfd_object)) {
bs_dbgmsg(" (!) bfd_check_format()\n");
bfd_close(abfd);
return NULL;
}
if((bin = malloc(sizeof(bincode_t))) == NULL) {
bs_errmsg(" (!) malloc(): bin\n");
exit(EXIT_FAILURE);
}
bin->filename = strdup(abfd->filename);
bin->abfd = abfd;
bin->filesize = bfd_get_size(abfd);
bin->start_addr = bfd_get_start_address(abfd);
init_disasm_info(bin->abfd, &bin->disasm_info);
bin->disasm_info.application_data = bin;
initialize_section(bin);
return bin;
}
/* Uses trace_read_memory, which assumes set_trace_bytes is used to update for each instruction. */
asm_program_t* asmir_trace_asmp_for_arch(enum bfd_architecture arch)
{
int machine = 0; // TODO: pick based on arch
asm_program_t *prog = malloc(sizeof(asm_program_t));
assert(prog);
prog->abfd = bfd_openw("/dev/null", NULL);
if (!prog->abfd) {
bfd_perror("Unable to open fake bfd");
}
assert(prog->abfd);
bfd_set_arch_info(prog->abfd, bfd_lookup_arch(arch, machine));
//not in .h bfd_default_set_arch_mach(prog->abfd, arch, machine);
bfd_set_arch_info(prog->abfd, bfd_lookup_arch(arch, machine));
init_disasm_info(prog);
// Use a special read memory function
prog->disasm_info.read_memory_func = trace_read_memory;
return prog;
}
// FIXME: the memory that gets allocated here is never freed.
void
initialize_sections(bfd *abfd, asm_program_t *prog)
{
struct disassemble_info *disasm_info = &prog->disasm_info;
unsigned int opb = bfd_octets_per_byte(abfd);
disasm_info->octets_per_byte = opb;
init_disasm_info(prog);
Segment *segs = NULL;
for(asection *section = abfd->sections;
section != (asection *) NULL; section = section->next){
Segment *seg, *ts;
int is_code = 0;
bfd_byte *data = NULL;
bfd_vma datasize = bfd_get_section_size_before_reloc(section);
if(datasize == 0) continue;
data = (bfd_byte *) xalloc((size_t) datasize, (size_t)
sizeof(bfd_byte));
bfd_get_section_contents(abfd, section, data, 0, datasize);
seg = (Segment *) xalloc(1, sizeof(Segment));
seg->data = data;
seg->datasize = datasize;
seg->start_addr = section->vma;
seg->end_addr = section->vma + datasize/opb;
seg->section = section;
if(section->flags & SEC_CODE == 0)
is_code = 0;
else
is_code = 1;
seg->is_code = is_code;
if(is_code){
/*seg->status = (unsigned char *)
xalloc((seg->end_addr - seg->start_addr), sizeof(char)); */
/*
seg->insts = (Instruction **) xalloc((seg->end_addr -
seg->start_addr),
sizeof(Instruction *));
//init_disasm_info(&disasm_info, seg);
for(bfd_vma pc = seg->start_addr; pc < seg->end_addr; ++pc){
Instruction *inst = get_inst_of(prog, pc, seg);
// DJB: Hack for stmxcsr and ldmxcsr instrs as found
// in atphttpd instr 806a36e
//if(inst->opcode[0] == 0xae && inst->opcode[1] == 0xf)
// inst->length++;
seg->insts[pc - seg->start_addr] = inst;
}
*/
seg->next = NULL;
if(segs == NULL)
segs = seg;
else{
ts = segs;
while(ts->next != NULL)
ts = ts->next;
ts->next = seg;
}
}
prog->sections[seg->start_addr] = seg;
}
prog->segs = segs;
}
void init_disasm_info(asm_program_t *prog)
{
init_disasm_info(prog->abfd, &prog->disasm_info);
prog->disasm_info.application_data = prog;
}
