void
load_strtab(Elf_Ehdr * pehdr, char *pexe)
{
Elf_Shdr *pshdr;
char *shname;
int i;
strtab = NULL;
for (i = 0; i < pehdr->e_shnum; i++) {
pshdr = (Elf_Shdr *) (pexe + pehdr->e_shoff +
(i * pehdr->e_shentsize));
shname = get_shstr(pshdr->sh_name);
if (strcmp(".strtab", shname) == 0)
break;
}
#ifdef DEBUG
fprint_shstr(stdout, pshdr->sh_name);
printf("\n");
#endif
strtab = (char *) (pexe + pshdr->sh_offset);
strtabsize = pshdr->sh_size;
#ifdef DEBUG
dump_strtab();
#endif
}
Elf32_Half find_section_index(char *name, Elf32_Ehdr *elf_h)
{
int i;
Elf32_Shdr *sect_hdr = (Elf32_Shdr *)((u_int32_t)elf_h + elf_h->e_shoff);
Elf32_Shdr *shstr_hdr = §_hdr[elf_h->e_shstrndx];
for (i = 0; i < elf_h->e_shnum; i++) {
char *a = get_shstr(elf_h, shstr_hdr, sect_hdr[i].sh_name);
if (strcmp(a, name) == 0)
return i;
}
return 0;
}
int find_symbol_in_elfhs(Elf32_Sym *in_symbol, Elf32_Sym **out_symbol, task_register_cons **out_symbol_trc,
task_register_cons *app_trc, Elf32_Ehdr *sys_elfh, task_register_tree *other_trcs)
{
Elf32_Sym *final_symbol = NULL;
task_register_cons *final_symbol_trc = NULL;
Elf32_Shdr *strtab_sect = find_section(".dynstr", app_trc->elfh);
char *symbol_name = get_shstr(app_trc->elfh, strtab_sect, in_symbol->st_name);
INFO_MSG("Relocating symbol %s\n", symbol_name);
if (in_symbol->st_shndx == SHN_UNDEF) {
/*
* Find the symbol elsewhere.
*/
if (other_trcs) {
task_register_cons *trcp;
TASK_ACQUIRE_TR_LOCK();
RB_FOREACH(trcp, task_register_tree_t, other_trcs) {
if (trcp == app_trc)
continue;
DEBUG_MSG("looking for symbol \"%s\" in \"%s\"\n", symbol_name, trcp->name);
final_symbol = find_symbol(symbol_name, trcp->elfh);
if (final_symbol == NULL)
continue;
if (final_symbol->st_shndx == SHN_UNDEF)
final_symbol = NULL;
if (final_symbol != NULL) {
final_symbol_trc = trcp;
break;
}
}
TASK_RELEASE_TR_LOCK();
}
if (final_symbol == NULL) {
final_symbol = find_symbol(symbol_name, sys_elfh);
/*
* If the symbol is found in the system elfh,
* let the symbol trc be NULL.
*/
final_symbol_trc = NULL;
}
} else {
Elf32_Sym *find_symbol(char *name, Elf32_Ehdr *elf_h)
{
int i;
char *tname;
Elf32_Shdr *symtab_sect = find_section(".symtab", elf_h);
Elf32_Shdr *strtab_sect = find_section(".strtab", elf_h);
DEBUG_MSG("Searching for symbol %s in elf @ 0x%x\n", name, (npi_t)elf_h);
if (symtab_sect == NULL) {
ERROR_MSG("Found no .symtab section\n");
return NULL;
}
if (strtab_sect == NULL) {
ERROR_MSG("Found no .strtab section\n");
return NULL;
}
if (symtab_sect->sh_entsize != sizeof(Elf32_Sym)) {
ERROR_MSG("Wrong .symtab entry size\n");
return NULL;
}
Elf32_Sym *syms = (Elf32_Sym *)((u_int32_t)elf_h + symtab_sect->sh_offset);
u_int32_t n = symtab_sect->sh_size / symtab_sect->sh_entsize;
INFO_MSG("Found %i entries in .symtab (sect at address 0x%x)\n", n, (unsigned int)syms);
for (i = 0; i < n; i++) {
tname = get_shstr(elf_h, strtab_sect, syms[i].st_name);
if (strcmp(tname, name) == 0) {
return &syms[i];
}
}
return NULL;
}
void
elf_hide(int pfile, char *p)
{
int i;
Elf_Ehdr *pehdr;
Elf_Shdr *pshdr;
Elf_Phdr *pphdr;
struct stat sb;
pexe = p;
pehdr = (Elf_Ehdr *) pexe;
#ifdef DEBUG
printf("elf header\n");
printf("e_type %x\n", pehdr->e_type);
printf("e_machine %x\n", pehdr->e_machine);
printf("e_version %x\n", pehdr->e_version);
printf("e_entry %x\n", pehdr->e_entry);
printf("e_phoff %x\n", pehdr->e_phoff);
printf("e_shoff %x\n", pehdr->e_shoff);
printf("e_flags %x\n", pehdr->e_flags);
printf("e_ehsize %x\n", pehdr->e_ehsize);
printf("e_phentsize %x\n", pehdr->e_phentsize);
printf("e_phnum %x\n", pehdr->e_phnum);
printf("e_shentsize %x\n", pehdr->e_shentsize);
printf("e_shnum %x\n", pehdr->e_shnum);
printf("e_shstrndx %x\n", pehdr->e_shstrndx);
#endif
load_shstr_tab(pehdr, pexe);
#ifdef DEBUG
for (i = 0; i < pehdr->e_shnum; i++) {
pshdr = (Elf_Phdr *) (pexe + pehdr->e_shoff +
(i * pehdr->e_shentsize));
printf("section header %d\n", i);
printf("sh_name %x ", pshdr->sh_name);
fprint_shstr(stdout, pshdr->sh_name);
printf("\n");
printf("sh_type %x\n", pshdr->sh_type);
printf("sh_flags %x\n", pshdr->sh_flags);
printf("sh_addr %x\n", pshdr->sh_addr);
printf("sh_offset %x\n", pshdr->sh_offset);
printf("sh_size %x\n", pshdr->sh_size);
printf("sh_link %x\n", pshdr->sh_link);
printf("sh_info %x\n", pshdr->sh_info);
printf("sh_addralign %x\n", pshdr->sh_addralign);
printf("sh_entsize %x\n", pshdr->sh_entsize);
}
#endif /* DEBUG */
#ifdef DEBUG
for (i = 0; i < pehdr->e_phnum; i++) {
pshdr = (Elf_Phdr *) (pexe + pehdr->e_phoff +
(i * pehdr->e_phentsize));
printf("program header %d\n", i);
printf("p_type %x\n", pphdr->p_type);
printf("p_offset %x\n", pphdr->p_offset);
printf("p_vaddr %x\n", pphdr->p_vaddr);
printf("p_paddr %x\n", pphdr->p_paddr);
printf("p_filesz %x\n", pphdr->p_filesz);
printf("p_memsz %x\n", pphdr->p_memsz);
printf("p_flags %x\n", pphdr->p_flags);
printf("p_align %x\n", pphdr->p_align);
}
#endif /* DEBUG */
#if 0
for (i = 0; i < pehdr->e_shnum; i++) {
pshdr = (Elf_Phdr *) (pexe + pehdr->e_shoff +
(i * pehdr->e_shentsize));
if (strcmp(".strtab", get_shstr(pshdr->sh_name)) == 0)
break;
}
fprint_shstr(stdout, pshdr->sh_name);
printf("\n");
#endif
load_strtab(pehdr, pexe);
load_symtab(pehdr, pexe);
munmap(pexe, sb.st_size);
close(pfile);
}
