2014-03-07 22:11:53 +01:00
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/*
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;* Copyright (C) 2014 Google, Inc.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "elfparsing.h"
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#include "rmodule.h"
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#include "../../src/include/rmodule-defs.h"
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struct rmod_context;
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struct arch_ops {
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int arch;
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/* Determine if relocation is a valid type for the architecture. */
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int (*valid_type)(struct rmod_context *ctx, Elf64_Rela *rel);
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/* Determine if relocation should be emitted. */
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int (*should_emit)(struct rmod_context *ctx, Elf64_Rela *rel);
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};
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struct rmod_context {
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/* Ops to process relocations. */
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struct arch_ops *ops;
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/* endian conversion ops */
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struct xdr *xdr;
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/* Parsed ELF sturcture. */
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struct parsed_elf pelf;
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/* Program segment. */
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Elf64_Phdr *phdr;
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/* Collection of relocation addresses fixup in the module. */
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Elf64_Xword nrelocs;
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Elf64_Addr *emitted_relocs;
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/* The following fields are addresses within the linked program. */
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Elf64_Addr link_addr;
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Elf64_Addr entry;
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Elf64_Addr parameters_begin;
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Elf64_Addr parameters_end;
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Elf64_Addr bss_begin;
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Elf64_Addr bss_end;
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Elf64_Xword size;
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};
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/*
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* Architecture specific support operations.
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*/
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static int valid_reloc_386(struct rmod_context *ctx, Elf64_Rela *rel)
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{
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int type;
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type = ELF64_R_TYPE(rel->r_info);
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/* Only these 2 relocations are expected to be found. */
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return (type == R_386_32 || type == R_386_PC32);
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}
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static int should_emit_386(struct rmod_context *ctx, Elf64_Rela *rel)
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{
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int type;
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type = ELF64_R_TYPE(rel->r_info);
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/* R_386_32 relocations are absolute. Must emit these. */
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return (type == R_386_32);
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}
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2014-03-20 17:08:02 +01:00
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static int valid_reloc_arm(struct rmod_context *ctx, Elf64_Rela *rel)
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{
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int type;
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type = ELF64_R_TYPE(rel->r_info);
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2014-07-23 22:42:22 +02:00
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/* Only these 6 relocations are expected to be found. */
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2014-03-20 17:08:02 +01:00
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return (type == R_ARM_ABS32 || type == R_ARM_THM_PC22 ||
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2014-07-23 22:42:22 +02:00
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type == R_ARM_THM_JUMP24 || type == R_ARM_V4BX ||
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type == R_ARM_CALL || type == R_ARM_JUMP24);
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2014-03-20 17:08:02 +01:00
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}
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static int should_emit_arm(struct rmod_context *ctx, Elf64_Rela *rel)
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{
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int type;
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type = ELF64_R_TYPE(rel->r_info);
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/* R_ARM_ABS32 relocations are absolute. Must emit these. */
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return (type == R_ARM_ABS32);
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}
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2014-08-27 00:21:15 +02:00
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static int valid_reloc_aarch64(struct rmod_context *ctx, Elf64_Rela *rel)
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{
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int type;
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type = ELF64_R_TYPE(rel->r_info);
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return (type == R_AARCH64_ADR_PREL_PG_HI21 ||
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type == R_AARCH64_ADD_ABS_LO12_NC ||
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2014-11-22 00:41:10 +01:00
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type == R_AARCH64_LDST8_ABS_LO12_NC ||
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2014-08-27 00:21:15 +02:00
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type == R_AARCH64_JUMP26 ||
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type == R_AARCH64_LDST32_ABS_LO12_NC ||
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2014-09-18 20:39:16 +02:00
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type == R_AARCH64_LDST64_ABS_LO12_NC ||
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2014-08-27 00:21:15 +02:00
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type == R_AARCH64_CALL26 ||
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type == R_AARCH64_ABS64 ||
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type == R_AARCH64_LD_PREL_LO19 ||
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type == R_AARCH64_ADR_PREL_LO21);
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}
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static int should_emit_aarch64(struct rmod_context *ctx, Elf64_Rela *rel)
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{
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int type;
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type = ELF64_R_TYPE(rel->r_info);
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return (type == R_AARCH64_ABS64);
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}
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2014-03-07 22:11:53 +01:00
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static struct arch_ops reloc_ops[] = {
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{
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.arch = EM_386,
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.valid_type = valid_reloc_386,
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.should_emit = should_emit_386,
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},
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2014-03-20 17:08:02 +01:00
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{
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.arch = EM_ARM,
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.valid_type = valid_reloc_arm,
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.should_emit = should_emit_arm,
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},
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2014-08-27 00:21:15 +02:00
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{
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.arch = EM_AARCH64,
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.valid_type = valid_reloc_aarch64,
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.should_emit = should_emit_aarch64,
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},
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2014-03-07 22:11:53 +01:00
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};
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/*
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* Relocation processing loops.
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*/
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static int for_each_reloc(struct rmod_context *ctx, int do_emit)
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{
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Elf64_Half i;
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struct parsed_elf *pelf = &ctx->pelf;
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for (i = 0; i < pelf->ehdr.e_shnum; i++) {
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Elf64_Shdr *shdr;
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Elf64_Rela *relocs;
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Elf64_Xword nrelocs;
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Elf64_Xword j;
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relocs = pelf->relocs[i];
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/* No relocations in this section. */
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if (relocs == NULL)
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continue;
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shdr = &pelf->shdr[i];
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nrelocs = shdr->sh_size / shdr->sh_entsize;
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for (j = 0; j < nrelocs; j++) {
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Elf64_Rela *r = &relocs[j];
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if (!ctx->ops->valid_type(ctx, r)) {
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ERROR("Invalid reloc type: %u\n",
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(unsigned int)ELF64_R_TYPE(r->r_info));
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return -1;
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}
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if (ctx->ops->should_emit(ctx, r)) {
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int n = ctx->nrelocs;
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if (do_emit)
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ctx->emitted_relocs[n] = r->r_offset;
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ctx->nrelocs++;
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}
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}
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}
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return 0;
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}
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static int find_program_segment(struct rmod_context *ctx)
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{
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int i;
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int nsegments;
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struct parsed_elf *pelf;
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Elf64_Phdr *phdr;
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pelf = &ctx->pelf;
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/* There should only be a single loadable segment. */
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nsegments = 0;
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for (i = 0; i < pelf->ehdr.e_phnum; i++) {
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if (pelf->phdr[i].p_type != PT_LOAD)
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continue;
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phdr = &pelf->phdr[i];
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nsegments++;
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}
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if (nsegments != 1) {
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ERROR("Unexepcted number of loadable segments: %d.\n",
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nsegments);
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return -1;
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}
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INFO("Segment at 0x%0llx, file size 0x%0llx, mem size 0x%0llx.\n",
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(long long)phdr->p_vaddr, (long long)phdr->p_filesz,
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(long long)phdr->p_memsz);
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ctx->phdr = phdr;
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return 0;
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}
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static int
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filter_relocation_sections(struct rmod_context *ctx)
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{
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int i;
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const char *shstrtab;
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struct parsed_elf *pelf;
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const Elf64_Phdr *phdr;
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pelf = &ctx->pelf;
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phdr = ctx->phdr;
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shstrtab = buffer_get(pelf->strtabs[pelf->ehdr.e_shstrndx]);
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/*
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* Find all relocation sections that contain relocation entries
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* for sections that fall within the bounds of the segment. For
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* easier processing the pointer to the relocation array for the
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* sections that don't fall within the loadable program are NULL'd
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* out.
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*/
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for (i = 0; i < pelf->ehdr.e_shnum; i++) {
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Elf64_Shdr *shdr;
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Elf64_Word sh_info;
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const char *section_name;
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shdr = &pelf->shdr[i];
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/* Ignore non-relocation sections. */
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if (shdr->sh_type != SHT_RELA && shdr->sh_type != SHT_REL)
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continue;
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/* Obtain section which relocations apply. */
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sh_info = shdr->sh_info;
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shdr = &pelf->shdr[sh_info];
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section_name = &shstrtab[shdr->sh_name];
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DEBUG("Relocation section found for '%s' section.\n",
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section_name);
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/* Do not process relocations for debug sections. */
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if (strstr(section_name, ".debug") != NULL) {
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pelf->relocs[i] = NULL;
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continue;
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}
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/*
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* If relocations apply to a non program section ignore the
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* relocations for future processing.
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*/
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if (shdr->sh_type != SHT_PROGBITS) {
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pelf->relocs[i] = NULL;
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continue;
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}
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if (shdr->sh_addr < phdr->p_vaddr ||
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((shdr->sh_addr + shdr->sh_size) >
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(phdr->p_vaddr + phdr->p_memsz))) {
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ERROR("Relocations being applied to section %d not "
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"within segment region.\n", sh_info);
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return -1;
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}
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}
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return 0;
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}
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static int vaddr_cmp(const void *a, const void *b)
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{
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const Elf64_Addr *pa = a;
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const Elf64_Addr *pb = b;
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if (*pa < *pb)
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return -1;
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if (*pa > *pb)
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return 1;
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return 0;
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}
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static int collect_relocations(struct rmod_context *ctx)
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{
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int nrelocs;
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/*
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* The relocs array in the pelf should only contain relocations that
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* apply to the program. Count the number relocations. Then collect
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* them into the allocated buffer.
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*/
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if (for_each_reloc(ctx, 0))
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return -1;
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nrelocs = ctx->nrelocs;
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INFO("%d relocations to be emitted.\n", nrelocs);
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2014-08-26 23:59:36 +02:00
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if (!nrelocs)
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return 0;
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2014-03-07 22:11:53 +01:00
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/* Reset the counter for indexing into the array. */
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ctx->nrelocs = 0;
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ctx->emitted_relocs = calloc(nrelocs, sizeof(Elf64_Addr));
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/* Write out the relocations into the emitted_relocs array. */
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if (for_each_reloc(ctx, 1))
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return -1;
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if (ctx->nrelocs != nrelocs) {
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ERROR("Mismatch counted and emitted relocations: %zu vs %zu.\n",
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(size_t)nrelocs, (size_t)ctx->nrelocs);
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return -1;
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}
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/* Sort the relocations by their address. */
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qsort(ctx->emitted_relocs, nrelocs, sizeof(Elf64_Addr), vaddr_cmp);
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return 0;
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}
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static int
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populate_sym(struct rmod_context *ctx, const char *sym_name, Elf64_Addr *addr,
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int nsyms, const char *strtab)
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{
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int i;
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Elf64_Sym *syms;
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syms = ctx->pelf.syms;
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for (i = 0; i < nsyms; i++) {
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if (syms[i].st_name == 0)
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continue;
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if (strcmp(sym_name, &strtab[syms[i].st_name]))
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continue;
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DEBUG("%s -> 0x%llx\n", sym_name, (long long)syms[i].st_value);
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*addr = syms[i].st_value;
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return 0;
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}
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ERROR("symbol '%s' not found.\n", sym_name);
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return -1;
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}
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static int populate_program_info(struct rmod_context *ctx)
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{
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int i;
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const char *strtab;
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struct parsed_elf *pelf;
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Elf64_Ehdr *ehdr;
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int nsyms;
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|
|
|
|
|
pelf = &ctx->pelf;
|
|
|
|
ehdr = &pelf->ehdr;
|
|
|
|
|
|
|
|
/* Obtain the string table. */
|
|
|
|
strtab = NULL;
|
|
|
|
for (i = 0; i < ehdr->e_shnum; i++) {
|
|
|
|
if (ctx->pelf.strtabs[i] == NULL)
|
|
|
|
continue;
|
|
|
|
/* Don't use the section headers' string table. */
|
|
|
|
if (i == ehdr->e_shstrndx)
|
|
|
|
continue;
|
|
|
|
strtab = buffer_get(ctx->pelf.strtabs[i]);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (strtab == NULL) {
|
|
|
|
ERROR("No string table found.\n");
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Determine number of symbols. */
|
|
|
|
nsyms = 0;
|
|
|
|
for (i = 0; i < ehdr->e_shnum; i++) {
|
|
|
|
if (pelf->shdr[i].sh_type != SHT_SYMTAB)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
nsyms = pelf->shdr[i].sh_size / pelf->shdr[i].sh_entsize;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (populate_sym(ctx, "_module_params_begin", &ctx->parameters_begin,
|
|
|
|
nsyms, strtab))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
if (populate_sym(ctx, "_module_params_end", &ctx->parameters_end,
|
|
|
|
nsyms, strtab))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
if (populate_sym(ctx, "_bss", &ctx->bss_begin, nsyms, strtab))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
if (populate_sym(ctx, "_ebss", &ctx->bss_end, nsyms, strtab))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
if (populate_sym(ctx, "__rmodule_entry", &ctx->entry, nsyms, strtab))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
/* Link address is the virtual address of the program segment. */
|
|
|
|
ctx->link_addr = ctx->phdr->p_vaddr;
|
|
|
|
|
|
|
|
/* The program size is the memsz of the program segment. */
|
|
|
|
ctx->size = ctx->phdr->p_memsz;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int
|
|
|
|
add_section(struct elf_writer *ew, struct buffer *data, const char *name,
|
|
|
|
Elf64_Addr addr, Elf64_Word size)
|
|
|
|
{
|
|
|
|
Elf64_Shdr shdr;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
memset(&shdr, 0, sizeof(shdr));
|
|
|
|
if (data != NULL) {
|
|
|
|
shdr.sh_type = SHT_PROGBITS;
|
|
|
|
shdr.sh_flags = SHF_ALLOC | SHF_WRITE | SHF_EXECINSTR;
|
|
|
|
} else {
|
|
|
|
shdr.sh_type = SHT_NOBITS;
|
|
|
|
shdr.sh_flags = SHF_ALLOC;
|
|
|
|
}
|
|
|
|
shdr.sh_addr = addr;
|
|
|
|
shdr.sh_offset = addr;
|
|
|
|
shdr.sh_size = size;
|
|
|
|
|
|
|
|
ret = elf_writer_add_section(ew, &shdr, data, name);
|
|
|
|
|
|
|
|
if (ret)
|
|
|
|
ERROR("Could not add '%s' section.\n", name);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int
|
|
|
|
write_elf(const struct rmod_context *ctx, const struct buffer *in,
|
|
|
|
struct buffer *out)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
int ret;
|
|
|
|
int bit64;
|
|
|
|
size_t loc;
|
|
|
|
size_t rmod_data_size;
|
|
|
|
struct elf_writer *ew;
|
|
|
|
struct buffer rmod_data;
|
|
|
|
struct buffer rmod_header;
|
|
|
|
struct buffer program;
|
|
|
|
struct buffer relocs;
|
|
|
|
Elf64_Xword total_size;
|
|
|
|
Elf64_Addr addr;
|
|
|
|
Elf64_Ehdr ehdr;
|
|
|
|
|
|
|
|
bit64 = ctx->pelf.ehdr.e_ident[EI_CLASS] == ELFCLASS64;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* 3 sections will be added to the ELF file.
|
|
|
|
* +------------------+
|
|
|
|
* | rmodule header |
|
|
|
|
* +------------------+
|
|
|
|
* | program |
|
|
|
|
* +------------------+
|
|
|
|
* | relocations |
|
|
|
|
* +------------------+
|
|
|
|
*/
|
|
|
|
|
|
|
|
/* Create buffer for header and relocations. */
|
|
|
|
rmod_data_size = sizeof(struct rmodule_header);
|
|
|
|
if (bit64)
|
|
|
|
rmod_data_size += ctx->nrelocs * sizeof(Elf64_Addr);
|
|
|
|
else
|
|
|
|
rmod_data_size += ctx->nrelocs * sizeof(Elf32_Addr);
|
|
|
|
|
|
|
|
if (buffer_create(&rmod_data, rmod_data_size, "rmod"))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
buffer_splice(&rmod_header, &rmod_data,
|
|
|
|
0, sizeof(struct rmodule_header));
|
|
|
|
buffer_clone(&relocs, &rmod_data);
|
|
|
|
buffer_seek(&relocs, sizeof(struct rmodule_header));
|
|
|
|
|
|
|
|
/* Reset current location. */
|
|
|
|
buffer_set_size(&rmod_header, 0);
|
|
|
|
buffer_set_size(&relocs, 0);
|
|
|
|
|
|
|
|
/* Program contents. */
|
|
|
|
buffer_splice(&program, in, ctx->phdr->p_offset, ctx->phdr->p_filesz);
|
|
|
|
|
|
|
|
/* Create ELF writer with modified entry point. */
|
|
|
|
memcpy(&ehdr, &ctx->pelf.ehdr, sizeof(ehdr));
|
|
|
|
ehdr.e_entry = ctx->entry;
|
|
|
|
ew = elf_writer_init(&ehdr);
|
|
|
|
|
|
|
|
if (ew == NULL) {
|
|
|
|
ERROR("Failed to create ELF writer.\n");
|
|
|
|
buffer_delete(&rmod_data);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Write out rmodule_header. */
|
|
|
|
ctx->xdr->put16(&rmod_header, RMODULE_MAGIC);
|
|
|
|
ctx->xdr->put8(&rmod_header, RMODULE_VERSION_1);
|
|
|
|
ctx->xdr->put8(&rmod_header, 0);
|
|
|
|
/* payload_begin_offset */
|
|
|
|
loc = sizeof(struct rmodule_header);
|
|
|
|
ctx->xdr->put32(&rmod_header, loc);
|
|
|
|
/* payload_end_offset */
|
|
|
|
loc += ctx->phdr->p_filesz;
|
|
|
|
ctx->xdr->put32(&rmod_header, loc);
|
|
|
|
/* relocations_begin_offset */
|
|
|
|
ctx->xdr->put32(&rmod_header, loc);
|
|
|
|
/* relocations_end_offset */
|
|
|
|
if (bit64)
|
|
|
|
loc += ctx->nrelocs * sizeof(Elf64_Addr);
|
|
|
|
else
|
|
|
|
loc += ctx->nrelocs * sizeof(Elf32_Addr);
|
|
|
|
ctx->xdr->put32(&rmod_header, loc);
|
|
|
|
/* module_link_start_address */
|
|
|
|
ctx->xdr->put32(&rmod_header, ctx->link_addr);
|
|
|
|
/* module_program_size */
|
|
|
|
ctx->xdr->put32(&rmod_header, ctx->size);
|
|
|
|
/* module_entry_point */
|
|
|
|
ctx->xdr->put32(&rmod_header, ctx->entry);
|
|
|
|
/* parameters_begin */
|
|
|
|
ctx->xdr->put32(&rmod_header, ctx->parameters_begin);
|
|
|
|
/* parameters_end */
|
|
|
|
ctx->xdr->put32(&rmod_header, ctx->parameters_end);
|
|
|
|
/* bss_begin */
|
|
|
|
ctx->xdr->put32(&rmod_header, ctx->bss_begin);
|
|
|
|
/* bss_end */
|
|
|
|
ctx->xdr->put32(&rmod_header, ctx->bss_end);
|
|
|
|
/* padding[4] */
|
|
|
|
ctx->xdr->put32(&rmod_header, 0);
|
|
|
|
ctx->xdr->put32(&rmod_header, 0);
|
|
|
|
ctx->xdr->put32(&rmod_header, 0);
|
|
|
|
ctx->xdr->put32(&rmod_header, 0);
|
|
|
|
|
|
|
|
/* Write the relocations. */
|
|
|
|
for (i = 0; i < ctx->nrelocs; i++) {
|
|
|
|
if (bit64)
|
|
|
|
ctx->xdr->put64(&relocs, ctx->emitted_relocs[i]);
|
|
|
|
else
|
|
|
|
ctx->xdr->put32(&relocs, ctx->emitted_relocs[i]);
|
|
|
|
}
|
|
|
|
|
|
|
|
total_size = 0;
|
|
|
|
addr = 0;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* There are 2 cases to deal with. The program has a large NOBITS
|
|
|
|
* section and the relocations can fit entirely within occupied memory
|
|
|
|
* region for the program. The other is that the relocations increase
|
|
|
|
* the memory footprint of the program if it was loaded directly into
|
|
|
|
* the region it would run. The rmdoule header is a fixed cost that
|
|
|
|
* is considered a part of the program.
|
|
|
|
*/
|
|
|
|
total_size += buffer_size(&rmod_header);
|
2014-08-26 20:52:30 +02:00
|
|
|
if (buffer_size(&relocs) + ctx->phdr->p_filesz > ctx->phdr->p_memsz) {
|
2014-03-07 22:11:53 +01:00
|
|
|
total_size += buffer_size(&relocs);
|
|
|
|
total_size += ctx->phdr->p_filesz;
|
2014-08-26 20:52:30 +02:00
|
|
|
} else {
|
|
|
|
total_size += ctx->phdr->p_memsz;
|
2014-03-07 22:11:53 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
ret = add_section(ew, &rmod_header, ".header", addr,
|
|
|
|
buffer_size(&rmod_header));
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
addr += buffer_size(&rmod_header);
|
|
|
|
|
|
|
|
ret = add_section(ew, &program, ".program", addr, ctx->phdr->p_filesz);
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
addr += ctx->phdr->p_filesz;
|
|
|
|
|
2014-08-26 23:59:36 +02:00
|
|
|
if (ctx->nrelocs) {
|
|
|
|
ret = add_section(ew, &relocs, ".relocs", addr,
|
|
|
|
buffer_size(&relocs));
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
addr += buffer_size(&relocs);
|
|
|
|
}
|
2014-03-07 22:11:53 +01:00
|
|
|
|
|
|
|
if (total_size != addr) {
|
|
|
|
ret = add_section(ew, NULL, ".empty", addr, total_size - addr);
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Ensure last section has a memory usage that meets the required
|
|
|
|
* total size of the program in memory.
|
|
|
|
*/
|
|
|
|
|
|
|
|
ret = elf_writer_serialize(ew, out);
|
|
|
|
if (ret < 0)
|
|
|
|
ERROR("Failed to serialize ELF to buffer.\n");
|
|
|
|
|
|
|
|
out:
|
|
|
|
buffer_delete(&rmod_data);
|
|
|
|
elf_writer_destroy(ew);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
int rmodule_create(const struct buffer *elfin, struct buffer *elfout)
|
|
|
|
{
|
|
|
|
struct rmod_context ctx;
|
|
|
|
struct parsed_elf *pelf;
|
|
|
|
int i;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = -1;
|
|
|
|
memset(&ctx, 0, sizeof(ctx));
|
|
|
|
pelf = &ctx.pelf;
|
|
|
|
|
|
|
|
if (parse_elf(elfin, pelf, ELF_PARSE_ALL)) {
|
|
|
|
ERROR("Couldn't parse ELF!\n");
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Only allow executables to be turned into rmodules. */
|
|
|
|
if (pelf->ehdr.e_type != ET_EXEC) {
|
|
|
|
ERROR("ELF is not an executable: %u.\n", pelf->ehdr.e_type);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Determine if architecture is supported. */
|
|
|
|
for (i = 0; i < ARRAY_SIZE(reloc_ops); i++) {
|
|
|
|
if (reloc_ops[i].arch == pelf->ehdr.e_machine) {
|
|
|
|
ctx.ops = &reloc_ops[i];
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (ctx.ops == NULL) {
|
|
|
|
ERROR("ELF is unsupported arch: %u.\n", pelf->ehdr.e_machine);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Set the endian ops. */
|
|
|
|
if (ctx.pelf.ehdr.e_ident[EI_DATA] == ELFDATA2MSB)
|
|
|
|
ctx.xdr = &xdr_be;
|
|
|
|
else
|
|
|
|
ctx.xdr = &xdr_le;
|
|
|
|
|
|
|
|
if (find_program_segment(&ctx))
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
if (filter_relocation_sections(&ctx))
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
if (collect_relocations(&ctx))
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
if (populate_program_info(&ctx))
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
if (write_elf(&ctx, elfin, elfout))
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
ret = 0;
|
|
|
|
|
|
|
|
out:
|
|
|
|
free(ctx.emitted_relocs);
|
|
|
|
parsed_elf_destroy(pelf);
|
|
|
|
return ret;
|
|
|
|
}
|