diff options
Diffstat (limited to 'grub-core/kern/arm64/dl.c')
| -rw-r--r-- | grub-core/kern/arm64/dl.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/grub-core/kern/arm64/dl.c b/grub-core/kern/arm64/dl.c new file mode 100644 index 0000000..512e5a8 --- /dev/null +++ b/grub-core/kern/arm64/dl.c @@ -0,0 +1,198 @@ +/* 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: + { + char rel_info[17]; /* log16(2^64) = 16, plus NUL. */ + + grub_snprintf (rel_info, sizeof (rel_info) - 1, "%" PRIxGRUB_UINT64_T, + ELF_R_TYPE (rel->r_info)); + return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, + N_("relocation 0x%s is not implemented yet"), rel_info); + } + } + } + + return GRUB_ERR_NONE; +} |