void test(void)
{
gadget_t gadgets;
gadget_init(&gadgets);
gadget_add(&gadgets, (unsigned char*)TEST_INSTRS, TEST_INSTRS_LEN, 0);
gadget_print(&gadgets);
gadget_destroy(&gadgets);
}
void gadget_destroy(gadget_t *gadgets)
{
/* Destroy all child nodes (if any). */
if (gadgets->previous.head != NULL) {
gadget_list_item_t *cursor = gadgets->previous.head;
while (cursor != NULL) {
gadget_destroy(cursor->gadget);
free(cursor->gadget);
cursor = cursor->next;
}
}
/* Destroy the linked-list of children. */
gadget_list_destroy(&gadgets->previous);
}
// allocate new gadget and copy old
struct gadget_t *gadget_new_copy(struct gadget_t *gadget) {
struct gadget_t *copy;
//
if (!gadget) {
debug_printf (MESSAGE_ERROR, stderr, "error: gadget_new_copy(): gadget was null\n");
return NULL;
}
// allocs
copy = gadget_new();
if (!copy) {
debug_printf (MESSAGE_ERROR, stderr, "error: gadget_new_copy(): copy was not allocated\n");
return NULL;
}
copy->repr = calloc(gadget->sz_repr, sizeof(*copy->repr));
copy->bytes = calloc(gadget->sz_bytes, sizeof(*copy->bytes));
// if one of the alloc failed
// then copied object failed
if (copy->repr == NULL || copy->bytes == NULL) {
debug_printf (MESSAGE_ERROR, stderr, "error: gadget_new_copy(): failed bytes or repr allocation\n");
free(copy->repr);
free(copy->bytes);
return NULL;
}
// if copy failed
// then bye
if (gadget_copy(copy, gadget) == NULL) {
debug_printf (MESSAGE_ERROR, stderr, "error: gadget_new_copy(): failed copy\n");
gadget_destroy(©);
return NULL;
}
return copy;
}
int main(int argc, char **argv)
{
if (argc != 2) {
print_usage();
return 1;
}
if (strcmp(argv[1], "demo") == 0) {
test();
return 0;
}
/* Code below adapted from 'libelf by Example' */
Elf *e;
GElf_Phdr phdr;
int fd;
size_t n, i;
if (elf_version(EV_CURRENT) == EV_NONE) {
printf("Error with elf library [%s]\n", elf_errmsg(-1));
exit(1);
}
if ((fd = open(argv[1], O_RDONLY, 0)) < 0) {
printf("Error reading file.\n");
exit(1);
}
if ((e = elf_begin(fd, ELF_C_READ, NULL)) == NULL) {
printf("elf_begin() failed [%s]\n", elf_errmsg(-1));
exit(1);
}
if (elf_kind(e) != ELF_K_ELF) {
printf("File is not an ELF object.\n");
exit(1);
}
if (elf_getphdrnum(e, &n) != 0) {
printf("elf_getphdrnum() failed [%s]\n", elf_errmsg(-1));
exit(1);
}
/* Initialize libdis */
x86_init(opt_none, NULL, NULL);
gadget_t gadgets;
gadget_init(&gadgets);
/* Loop over each program header (segment) */
for (i = 0; i < n; i++) {
if (gelf_getphdr(e, i, &phdr) != &phdr) {
printf("gelf_getphdr() failed [%s]\n", elf_errmsg(-1));
exit(1);
}
/* If the segment is loaded into memory AND is executable */
if (phdr.p_type == PT_LOAD && phdr.p_flags & PF_X) {
/* Load the segment from the ELF file */
unsigned char *buffer = malloc(phdr.p_filesz);
lseek(fd, phdr.p_offset, SEEK_SET);
ssize_t count = read(fd, buffer, phdr.p_filesz);
if (count != phdr.p_filesz) {
printf("read sucks.\n"); // FIXME: EINTR etc.
exit(1);
}
/* Add all gadgets in the segment to our gadget tree */
gadget_add(&gadgets, buffer, phdr.p_filesz, phdr.p_vaddr);
free(buffer);
}
}
elf_end(e);
close(fd);
gadget_print(&gadgets);
gadget_destroy(&gadgets);
return 0;
}
