/* * Apply relocations to the values we got from the file. `relbase' is the * target relocation address of the section, and `dataoff' is the target * relocation address of the data in `dest'. */ int ef_reloc(struct elf_file *ef, const void *reldata, int reltype, Elf_Off relbase, Elf_Off dataoff, size_t len, void *_dest) { Elf_Addr *where, addr, addend; Elf_Size rtype, symidx; const Elf_Rel *rel; const Elf_Rela *rela; char *dest = _dest; switch (reltype) { case EF_RELOC_REL: rel = (const Elf_Rel *)reldata; where = (Elf_Addr *)(dest + relbase + rel->r_offset - dataoff); addend = 0; rtype = ELF_R_TYPE(rel->r_info); symidx = ELF_R_SYM(rel->r_info); break; case EF_RELOC_RELA: rela = (const Elf_Rela *)reldata; where = (Elf_Addr *)(dest + relbase + rela->r_offset - dataoff); addend = rela->r_addend; rtype = ELF_R_TYPE(rela->r_info); symidx = ELF_R_SYM(rela->r_info); break; default: return (EINVAL); } if ((char *)where < (char *)dest || (char *)where >= (char *)dest + len) return (0); if (reltype == EF_RELOC_REL) addend = *where; switch (rtype) { case R_386_RELATIVE: /* A + B */ addr = (Elf_Addr)addend + relbase; *where = addr; break; case R_386_32: /* S + A - P */ addr = EF_SYMADDR(ef, symidx); addr += addend; *where = addr; break; case R_386_GLOB_DAT: /* S */ addr = EF_SYMADDR(ef, symidx); *where = addr; break; default: warnx("unhandled relocation type %d", (int)rtype); } return (0); }
/* * Apply relocations to the values we got from the file. `relbase' is the * target relocation address of the section, and `dataoff' is the target * relocation address of the data in `dest'. */ int ef_reloc(struct elf_file *ef, const void *reldata, int reltype, Elf_Off relbase, Elf_Off dataoff, size_t len, void *dest) { Elf64_Addr *where, val; Elf32_Addr *where32, val32; Elf_Addr addend, addr; Elf_Size rtype, symidx; const Elf_Rel *rel; const Elf_Rela *rela; switch (reltype) { case EF_RELOC_REL: rel = (const Elf_Rel *)reldata; where = (Elf_Addr *)(dest + relbase + rel->r_offset - dataoff); addend = 0; rtype = ELF_R_TYPE(rel->r_info); symidx = ELF_R_SYM(rel->r_info); break; case EF_RELOC_RELA: rela = (const Elf_Rela *)reldata; where = (Elf_Addr *)(dest + relbase + rela->r_offset - dataoff); addend = rela->r_addend; rtype = ELF_R_TYPE(rela->r_info); symidx = ELF_R_SYM(rela->r_info); break; default: return (EINVAL); } if ((char *)where < (char *)dest || (char *)where >= (char *)dest + len) return (0); if (reltype == EF_RELOC_REL) { /* Addend is 32 bit on 32 bit relocs */ switch (rtype) { case R_X86_64_PC32: case R_X86_64_32S: addend = *(Elf32_Addr *)where; break; default: addend = *where; break; } } switch (rtype) { case R_X86_64_NONE: /* none */ break; case R_X86_64_64: /* S + A */ addr = EF_SYMADDR(ef, symidx); val = addr + addend; *where = val; break; case R_X86_64_32S: /* S + A sign extend */ addr = EF_SYMADDR(ef, symidx); val32 = (Elf32_Addr)(addr + addend); where32 = (Elf32_Addr *)where; *where32 = val32; break; case R_X86_64_GLOB_DAT: /* S */ addr = EF_SYMADDR(ef, symidx); *where = addr; break; case R_X86_64_RELATIVE: /* B + A */ addr = (Elf_Addr)addend + relbase; val = addr; *where = val; break; default: warnx("unhandled relocation type %d", (int)rtype); } return (0); }