| /* dl.c - arch-dependent part of loadable module support */ |
| /* |
| * GRUB -- GRand Unified Bootloader |
| * Copyright (C) 2013 Free Software Foundation, Inc. |
| * |
| * GRUB is free software: you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation, either version 3 of the License, or |
| * (at your option) any later version. |
| * |
| * GRUB is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with GRUB. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <grub/dl.h> |
| #include <grub/elf.h> |
| #include <grub/misc.h> |
| #include <grub/err.h> |
| #include <grub/mm.h> |
| #include <grub/i18n.h> |
| #include <grub/cpu/reloc.h> |
| |
| #define LDR 0x58000050 |
| #define BR 0xd61f0200 |
| |
| |
| /* |
| * Check if EHDR is a valid ELF header. |
| */ |
| grub_err_t |
| grub_arch_dl_check_header (void *ehdr) |
| { |
| Elf_Ehdr *e = ehdr; |
| |
| /* Check the magic numbers. */ |
| if (e->e_ident[EI_CLASS] != ELFCLASS64 |
| || e->e_ident[EI_DATA] != ELFDATA2LSB || e->e_machine != EM_AARCH64) |
| return grub_error (GRUB_ERR_BAD_OS, |
| N_("invalid arch-dependent ELF magic")); |
| |
| return GRUB_ERR_NONE; |
| } |
| |
| #pragma GCC diagnostic ignored "-Wcast-align" |
| |
| /* |
| * Unified function for both REL and RELA |
| */ |
| grub_err_t |
| grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr, |
| Elf_Shdr *s, grub_dl_segment_t seg) |
| { |
| Elf_Rel *rel, *max; |
| unsigned unmatched_adr_got_page = 0; |
| |
| for (rel = (Elf_Rel *) ((char *) ehdr + s->sh_offset), |
| max = (Elf_Rel *) ((char *) rel + s->sh_size); |
| rel < max; |
| rel = (Elf_Rel *) ((char *) rel + s->sh_entsize)) |
| { |
| Elf_Sym *sym; |
| void *place; |
| grub_uint64_t sym_addr; |
| |
| if (rel->r_offset >= seg->size) |
| return grub_error (GRUB_ERR_BAD_MODULE, |
| "reloc offset is out of the segment"); |
| |
| sym = (Elf_Sym *) ((char *) mod->symtab |
| + mod->symsize * ELF_R_SYM (rel->r_info)); |
| |
| sym_addr = sym->st_value; |
| if (s->sh_type == SHT_RELA) |
| sym_addr += ((Elf_Rela *) rel)->r_addend; |
| |
| place = (void *) ((grub_addr_t) seg->addr + rel->r_offset); |
| |
| switch (ELF_R_TYPE (rel->r_info)) |
| { |
| case R_AARCH64_ABS64: |
| { |
| grub_uint64_t *abs_place = place; |
| |
| grub_dprintf ("dl", " reloc_abs64 %p => 0x%016llx\n", |
| place, (unsigned long long) sym_addr); |
| |
| *abs_place = (grub_uint64_t) sym_addr; |
| } |
| break; |
| case R_AARCH64_ADD_ABS_LO12_NC: |
| grub_arm64_set_abs_lo12 (place, sym_addr); |
| break; |
| case R_AARCH64_LDST64_ABS_LO12_NC: |
| grub_arm64_set_abs_lo12_ldst64 (place, sym_addr); |
| break; |
| case R_AARCH64_CALL26: |
| case R_AARCH64_JUMP26: |
| { |
| grub_int64_t offset = sym_addr - (grub_uint64_t) place; |
| |
| if (!grub_arm_64_check_xxxx26_offset (offset)) |
| { |
| struct grub_arm64_trampoline *tp = mod->trampptr; |
| mod->trampptr = tp + 1; |
| tp->ldr = LDR; |
| tp->br = BR; |
| tp->addr = sym_addr; |
| offset = (grub_uint8_t *) tp - (grub_uint8_t *) place; |
| } |
| |
| if (!grub_arm_64_check_xxxx26_offset (offset)) |
| return grub_error (GRUB_ERR_BAD_MODULE, |
| "trampoline out of range"); |
| |
| grub_arm64_set_xxxx26_offset (place, offset); |
| } |
| break; |
| case R_AARCH64_PREL32: |
| { |
| grub_int64_t value; |
| Elf64_Word *addr32 = place; |
| value = ((grub_int32_t) *addr32) + sym_addr - |
| (Elf64_Xword) (grub_addr_t) seg->addr - rel->r_offset; |
| if (value != (grub_int32_t) value) |
| return grub_error (GRUB_ERR_BAD_MODULE, "relocation out of range"); |
| grub_dprintf("dl", " reloc_prel32 %p => 0x%016llx\n", |
| place, (unsigned long long) sym_addr); |
| *addr32 = value; |
| } |
| break; |
| case R_AARCH64_ADR_GOT_PAGE: |
| { |
| grub_uint64_t *gp = mod->gotptr; |
| Elf_Rela *rel2; |
| grub_int64_t gpoffset = ((grub_uint64_t) gp & ~0xfffULL) - (((grub_uint64_t) place) & ~0xfffULL); |
| *gp = (grub_uint64_t) sym_addr; |
| mod->gotptr = gp + 1; |
| unmatched_adr_got_page++; |
| grub_dprintf("dl", " reloc_got %p => 0x%016llx (0x%016llx)\n", |
| place, (unsigned long long) sym_addr, (unsigned long long) gp); |
| if (!grub_arm64_check_hi21_signed (gpoffset)) |
| return grub_error (GRUB_ERR_BAD_MODULE, |
| "HI21 out of range"); |
| grub_arm64_set_hi21(place, gpoffset); |
| for (rel2 = (Elf_Rela *) ((char *) rel + s->sh_entsize); |
| rel2 < (Elf_Rela *) max; |
| rel2 = (Elf_Rela *) ((char *) rel2 + s->sh_entsize)) |
| if (ELF_R_SYM (rel2->r_info) |
| == ELF_R_SYM (rel->r_info) |
| && ((Elf_Rela *) rel)->r_addend == rel2->r_addend |
| && ELF_R_TYPE (rel2->r_info) == R_AARCH64_LD64_GOT_LO12_NC) |
| { |
| grub_arm64_set_abs_lo12_ldst64 ((void *) ((grub_addr_t) seg->addr + rel2->r_offset), |
| (grub_uint64_t)gp); |
| break; |
| } |
| if (rel2 >= (Elf_Rela *) max) |
| return grub_error (GRUB_ERR_BAD_MODULE, |
| "ADR_GOT_PAGE without matching LD64_GOT_LO12_NC"); |
| } |
| break; |
| case R_AARCH64_LD64_GOT_LO12_NC: |
| if (unmatched_adr_got_page == 0) |
| return grub_error (GRUB_ERR_BAD_MODULE, |
| "LD64_GOT_LO12_NC without matching ADR_GOT_PAGE"); |
| unmatched_adr_got_page--; |
| break; |
| case R_AARCH64_ADR_PREL_PG_HI21: |
| { |
| grub_int64_t offset = (sym_addr & ~0xfffULL) - (((grub_uint64_t) place) & ~0xfffULL); |
| |
| if (!grub_arm64_check_hi21_signed (offset)) |
| return grub_error (GRUB_ERR_BAD_MODULE, |
| "HI21 out of range"); |
| |
| grub_arm64_set_hi21 (place, offset); |
| } |
| break; |
| |
| default: |
| return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, |
| N_("relocation 0x%x is not implemented yet"), |
| ELF_R_TYPE (rel->r_info)); |
| } |
| } |
| |
| return GRUB_ERR_NONE; |
| } |