leandrof/u-boot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
b4108f3fd3
u-boot/tools/relocate-rela.c
Michal Simek 034944b33b tools: relocate-rela: Add support for 32bit Microblaze relocation 
Microblaze is 32bit that's why it is using elf32 format. Relocation code
requires to get information about rela and dynsym senctions and also text
base which was used for compilation.
Code build with -fPIC and linked with -pic generates 4 relocation types.
R_MICROBLAZE_NONE is the easiest one which doesn't require any action.
R_MICROBLAZE_REL only requires write addend to r_offset address.
R_MICROBLAZE_32/R_MICROBLAZE_GLOB_DAT are the most complicated. There is a
need to find out symbol value with adding symbol value and write it to
address pointed by r_offset. Calculation with addend is also added but
only 0 addend values are generated now.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/9912c3d76933bdf75e1ebb6aab43726cd32cafb5.1655299267.git.michal.simek@amd.com
2022-06-24 14:15:00 +02:00

645 lines
15 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0+ OR BSD-2-Clause
/*
* Copyright 2013 Freescale Semiconductor, Inc.
*
* 64-bit and little-endian target only until we need to support a different
* arch that needs this.
*/
#include <elf.h>
#include <errno.h>
#include <inttypes.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "compiler.h"
#ifndef R_AARCH64_RELATIVE
#define R_AARCH64_RELATIVE 1027
#endif
static int ei_class;
static uint64_t rela_start, rela_end, text_base, dyn_start;
static const bool debug_en;
static void debug(const char *fmt, ...)
{
va_list args;
if (debug_en) {
va_start(args, fmt);
vprintf(fmt, args);
va_end(args);
}
}
static bool supported_rela(Elf64_Rela *rela)
{
uint64_t mask = 0xffffffffULL; /* would be different on 32-bit */
uint32_t type = rela->r_info & mask;
switch (type) {
#ifdef R_AARCH64_RELATIVE
case R_AARCH64_RELATIVE:
return true;
#endif
default:
fprintf(stderr, "warning: unsupported relocation type %"
PRIu32 " at %" PRIx64 "\n",
type, rela->r_offset);
return false;
}
}
static int decode_elf64(FILE *felf, char **argv)
{
size_t size;
Elf64_Ehdr header;
uint64_t section_header_base, section_header_size, sh_offset, sh_size;
Elf64_Shdr *sh_table; /* Elf symbol table */
int ret, i, machine;
char *sh_str;
debug("64bit version\n");
/* Make sure we are at start */
rewind(felf);
size = fread(&header, 1, sizeof(header), felf);
if (size != sizeof(header)) {
fclose(felf);
return 25;
}
machine = header.e_machine;
debug("Machine\t%d\n", machine);
if (machine != EM_AARCH64) {
fprintf(stderr, "%s: Not supported machine type\n", argv[0]);
return 30;
}
text_base = header.e_entry;
section_header_base = header.e_shoff;
section_header_size = header.e_shentsize * header.e_shnum;
sh_table = malloc(section_header_size);
if (!sh_table) {
fprintf(stderr, "%s: Cannot allocate space for section header\n",
argv[0]);
fclose(felf);
return 26;
}
ret = fseek(felf, section_header_base, SEEK_SET);
if (ret) {
fprintf(stderr, "%s: Can't set pointer to section header: %x/%lx\n",
argv[0], ret, section_header_base);
free(sh_table);
fclose(felf);
return 26;
}
size = fread(sh_table, 1, section_header_size, felf);
if (size != section_header_size) {
fprintf(stderr, "%s: Can't read section header: %lx/%lx\n",
argv[0], size, section_header_size);
free(sh_table);
fclose(felf);
return 27;
}
sh_size = sh_table[header.e_shstrndx].sh_size;
debug("e_shstrndx\t0x%08x\n", header.e_shstrndx);
debug("sh_size\t\t0x%08lx\n", sh_size);
sh_str = malloc(sh_size);
if (!sh_str) {
fprintf(stderr, "malloc failed\n");
free(sh_table);
fclose(felf);
return 28;
}
/*
* Specifies the byte offset from the beginning of the file
* to the first byte in the section.
*/
sh_offset = sh_table[header.e_shstrndx].sh_offset;
debug("sh_offset\t0x%08x\n", header.e_shnum);
ret = fseek(felf, sh_offset, SEEK_SET);
if (ret) {
fprintf(stderr, "Setting up sh_offset failed\n");
free(sh_str);
free(sh_table);
fclose(felf);
return 29;
}
size = fread(sh_str, 1, sh_size, felf);
if (size != sh_size) {
fprintf(stderr, "%s: Can't read section: %lx/%lx\n",
argv[0], size, sh_size);
free(sh_str);
free(sh_table);
fclose(felf);
return 30;
}
for (i = 0; i < header.e_shnum; i++) {
/* fprintf(stderr, "%s\n", sh_str + sh_table[i].sh_name); Debug only */
if (!strcmp(".rela.dyn", (sh_str + sh_table[i].sh_name))) {
debug("Found section\t\".rela_dyn\"\n");
debug(" at addr\t0x%08x\n",
(unsigned int)sh_table[i].sh_addr);
debug(" at offset\t0x%08x\n",
(unsigned int)sh_table[i].sh_offset);
debug(" of size\t0x%08x\n",
(unsigned int)sh_table[i].sh_size);
rela_start = sh_table[i].sh_addr;
rela_end = rela_start + sh_table[i].sh_size;
break;
}
}
/* Clean up */
free(sh_str);
free(sh_table);
fclose(felf);
debug("text_base\t0x%08lx\n", text_base);
debug("rela_start\t0x%08lx\n", rela_start);
debug("rela_end\t0x%08lx\n", rela_end);
if (!rela_start)
return 1;
return 0;
}
static int decode_elf32(FILE *felf, char **argv)
{
size_t size;
Elf32_Ehdr header;
uint64_t section_header_base, section_header_size, sh_offset, sh_size;
Elf32_Shdr *sh_table; /* Elf symbol table */
int ret, i, machine;
char *sh_str;
debug("32bit version\n");
/* Make sure we are at start */
rewind(felf);
size = fread(&header, 1, sizeof(header), felf);
if (size != sizeof(header)) {
fclose(felf);
return 25;
}
machine = header.e_machine;
debug("Machine %d\n", machine);
if (machine != EM_MICROBLAZE) {
fprintf(stderr, "%s: Not supported machine type\n", argv[0]);
return 30;
}
text_base = header.e_entry;
section_header_base = header.e_shoff;
debug("Section header base %x\n", section_header_base);
section_header_size = header.e_shentsize * header.e_shnum;
debug("Section header size %d\n", section_header_size);
sh_table = malloc(section_header_size);
if (!sh_table) {
fprintf(stderr, "%s: Cannot allocate space for section header\n",
argv[0]);
fclose(felf);
return 26;
}
ret = fseek(felf, section_header_base, SEEK_SET);
if (ret) {
fprintf(stderr, "%s: Can't set pointer to section header: %x/%lx\n",
argv[0], ret, section_header_base);
free(sh_table);
fclose(felf);
return 26;
}
size = fread(sh_table, 1, section_header_size, felf);
if (size != section_header_size) {
fprintf(stderr, "%s: Can't read section header: %lx/%lx\n",
argv[0], size, section_header_size);
free(sh_table);
fclose(felf);
return 27;
}
sh_size = sh_table[header.e_shstrndx].sh_size;
debug("e_shstrndx %x, sh_size %lx\n", header.e_shstrndx, sh_size);
sh_str = malloc(sh_size);
if (!sh_str) {
fprintf(stderr, "malloc failed\n");
free(sh_table);
fclose(felf);
return 28;
}
/*
* Specifies the byte offset from the beginning of the file
* to the first byte in the section.
*/
sh_offset = sh_table[header.e_shstrndx].sh_offset;
debug("sh_offset %x\n", header.e_shnum);
ret = fseek(felf, sh_offset, SEEK_SET);
if (ret) {
fprintf(stderr, "Setting up sh_offset failed\n");
free(sh_str);
free(sh_table);
fclose(felf);
return 29;
}
size = fread(sh_str, 1, sh_size, felf);
if (size != sh_size) {
fprintf(stderr, "%s: Can't read section: %lx/%lx\n",
argv[0], size, sh_size);
free(sh_str);
free(sh_table);
fclose(felf);
return 30;
}
for (i = 0; i < header.e_shnum; i++) {
debug("%s\n", sh_str + sh_table[i].sh_name);
if (!strcmp(".rela.dyn", (sh_str + sh_table[i].sh_name))) {
debug("Found section\t\".rela_dyn\"\n");
debug(" at addr\t0x%08x\n", (unsigned int)sh_table[i].sh_addr);
debug(" at offset\t0x%08x\n", (unsigned int)sh_table[i].sh_offset);
debug(" of size\t0x%08x\n", (unsigned int)sh_table[i].sh_size);
rela_start = sh_table[i].sh_addr;
rela_end = rela_start + sh_table[i].sh_size;
}
if (!strcmp(".dynsym", (sh_str + sh_table[i].sh_name))) {
debug("Found section\t\".dynsym\"\n");
debug(" at addr\t0x%08x\n", (unsigned int)sh_table[i].sh_addr);
debug(" at offset\t0x%08x\n", (unsigned int)sh_table[i].sh_offset);
debug(" of size\t0x%08x\n", (unsigned int)sh_table[i].sh_size);
dyn_start = sh_table[i].sh_addr;
}
}
/* Clean up */
free(sh_str);
free(sh_table);
fclose(felf);
debug("text_base\t0x%08lx\n", text_base);
debug("rela_start\t0x%08lx\n", rela_start);
debug("rela_end\t0x%08lx\n", rela_end);
debug("dyn_start\t0x%08lx\n", dyn_start);
if (!rela_start)
return 1;
return 0;
}
static int decode_elf(char **argv)
{
FILE *felf;
size_t size;
unsigned char e_ident[EI_NIDENT];
felf = fopen(argv[2], "r+b");
if (!felf) {
fprintf(stderr, "%s: Cannot open %s: %s\n",
argv[0], argv[5], strerror(errno));
return 2;
}
size = fread(e_ident, 1, EI_NIDENT, felf);
if (size != EI_NIDENT) {
fclose(felf);
return 25;
}
/* Check if this is really ELF file */
if (e_ident[0] != 0x7f &&
e_ident[1] != 'E' &&
e_ident[2] != 'L' &&
e_ident[3] != 'F') {
fclose(felf);
return 1;
}
ei_class = e_ident[4];
debug("EI_CLASS(1=32bit, 2=64bit) %d\n", ei_class);
if (ei_class == 2)
return decode_elf64(felf, argv);
return decode_elf32(felf, argv);
}
static int rela_elf64(char **argv, FILE *f)
{
int i, num;
if ((rela_end - rela_start) % sizeof(Elf64_Rela)) {
fprintf(stderr, "%s: rela size isn't a multiple of Elf64_Rela\n", argv[0]);
return 3;
}
num = (rela_end - rela_start) / sizeof(Elf64_Rela);
for (i = 0; i < num; i++) {
Elf64_Rela rela, swrela;
uint64_t pos = rela_start + sizeof(Elf64_Rela) * i;
uint64_t addr;
if (fseek(f, pos, SEEK_SET) < 0) {
fprintf(stderr, "%s: %s: seek to %" PRIx64
" failed: %s\n",
argv[0], argv[1], pos, strerror(errno));
}
if (fread(&rela, sizeof(rela), 1, f) != 1) {
fprintf(stderr, "%s: %s: read rela failed at %"
PRIx64 "\n",
argv[0], argv[1], pos);
return 4;
}
swrela.r_offset = cpu_to_le64(rela.r_offset);
swrela.r_info = cpu_to_le64(rela.r_info);
swrela.r_addend = cpu_to_le64(rela.r_addend);
if (!supported_rela(&swrela))
continue;
debug("Rela %" PRIx64 " %" PRIu64 " %" PRIx64 "\n",
swrela.r_offset, swrela.r_info, swrela.r_addend);
if (swrela.r_offset < text_base) {
fprintf(stderr, "%s: %s: bad rela at %" PRIx64 "\n",
argv[0], argv[1], pos);
return 4;
}
addr = swrela.r_offset - text_base;
if (fseek(f, addr, SEEK_SET) < 0) {
fprintf(stderr, "%s: %s: seek to %"
PRIx64 " failed: %s\n",
argv[0], argv[1], addr, strerror(errno));
}
if (fwrite(&rela.r_addend, sizeof(rela.r_addend), 1, f) != 1) {
fprintf(stderr, "%s: %s: write failed at %" PRIx64 "\n",
argv[0], argv[1], addr);
return 4;
}
}
return 0;
}
static bool supported_rela32(Elf32_Rela *rela, uint32_t *type)
{
uint32_t mask = 0xffULL; /* would be different on 32-bit */
*type = rela->r_info & mask;
debug("Type:\t");
switch (*type) {
case R_MICROBLAZE_32:
debug("R_MICROBLAZE_32\n");
return true;
case R_MICROBLAZE_GLOB_DAT:
debug("R_MICROBLAZE_GLOB_DAT\n");
return true;
case R_MICROBLAZE_NONE:
debug("R_MICROBLAZE_NONE - ignoring - do nothing\n");
return false;
case R_MICROBLAZE_REL:
debug("R_MICROBLAZE_REL\n");
return true;
default:
fprintf(stderr, "warning: unsupported relocation type %"
PRIu32 " at %" PRIx32 "\n", *type, rela->r_offset);
return false;
}
}
static int rela_elf32(char **argv, FILE *f)
{
int i, num, index;
uint32_t value, type;
if ((rela_end - rela_start) % sizeof(Elf32_Rela)) {
fprintf(stderr, "%s: rela size isn't a multiple of Elf32_Rela\n", argv[0]);
return 3;
}
num = (rela_end - rela_start) / sizeof(Elf32_Rela);
debug("Number of entries: %u\n", num);
for (i = 0; i < num; i++) {
Elf32_Rela rela, swrela;
Elf32_Sym symbols;
uint32_t pos = rela_start + sizeof(Elf32_Rela) * i;
uint32_t addr, pos_dyn;
debug("\nPossition:\t%d/0x%x\n", i, pos);
if (fseek(f, pos, SEEK_SET) < 0) {
fprintf(stderr, "%s: %s: seek to %" PRIx32
" failed: %s\n",
argv[0], argv[1], pos, strerror(errno));
}
if (fread(&rela, sizeof(rela), 1, f) != 1) {
fprintf(stderr, "%s: %s: read rela failed at %"
PRIx32 "\n",
argv[0], argv[1], pos);
return 4;
}
debug("Rela:\toffset:\t%" PRIx32 " r_info:\t%"
PRIu32 " r_addend:\t%" PRIx32 "\n",
rela.r_offset, rela.r_info, rela.r_addend);
swrela.r_offset = cpu_to_le32(rela.r_offset);
swrela.r_info = cpu_to_le32(rela.r_info);
swrela.r_addend = cpu_to_le32(rela.r_addend);
debug("SWRela:\toffset:\t%" PRIx32 " r_info:\t%"
PRIu32 " r_addend:\t%" PRIx32 "\n",
swrela.r_offset, swrela.r_info, swrela.r_addend);
if (!supported_rela32(&swrela, &type))
continue;
if (swrela.r_offset < text_base) {
fprintf(stderr, "%s: %s: bad rela at %" PRIx32 "\n",
argv[0], argv[1], pos);
return 4;
}
addr = swrela.r_offset - text_base;
debug("Addr:\t0x%" PRIx32 "\n", addr);
switch (type) {
case R_MICROBLAZE_REL:
if (fseek(f, addr, SEEK_SET) < 0) {
fprintf(stderr, "%s: %s: seek to %"
PRIx32 " failed: %s\n",
argv[0], argv[1], addr, strerror(errno));
return 5;
}
debug("Write addend\n");
if (fwrite(&rela.r_addend, sizeof(rela.r_addend), 1, f) != 1) {
fprintf(stderr, "%s: %s: write failed at %" PRIx32 "\n",
argv[0], argv[1], addr);
return 4;
}
break;
case R_MICROBLAZE_32:
case R_MICROBLAZE_GLOB_DAT:
/* global symbols read it and add reloc offset */
index = swrela.r_info >> 8;
pos_dyn = dyn_start + sizeof(Elf32_Sym) * index;
debug("Index:\t%d\n", index);
debug("Pos_dyn:\t0x%x\n", pos_dyn);
if (fseek(f, pos_dyn, SEEK_SET) < 0) {
fprintf(stderr, "%s: %s: seek to %"
PRIx32 " failed: %s\n",
argv[0], argv[1], pos_dyn, strerror(errno));
return 5;
}
if (fread(&symbols, sizeof(symbols), 1, f) != 1) {
fprintf(stderr, "%s: %s: read symbols failed at %"
PRIx32 "\n",
argv[0], argv[1], pos_dyn);
return 4;
}
debug("Symbol description:\n");
debug(" st_name:\t0x%x\n", symbols.st_name);
debug(" st_value:\t0x%x\n", symbols.st_value);
debug(" st_size:\t0x%x\n", symbols.st_size);
value = swrela.r_addend + symbols.st_value;
debug("Value:\t0x%x\n", value);
if (fseek(f, addr, SEEK_SET) < 0) {
fprintf(stderr, "%s: %s: seek to %"
PRIx32 " failed: %s\n",
argv[0], argv[1], addr, strerror(errno));
return 5;
}
if (fwrite(&value, sizeof(rela.r_addend), 1, f) != 1) {
fprintf(stderr, "%s: %s: write failed at %" PRIx32 "\n",
argv[0], argv[1], addr);
return 4;
}
break;
case R_MICROBLAZE_NONE:
debug("R_MICROBLAZE_NONE - skip\n");
break;
default:
fprintf(stderr, "warning: unsupported relocation type %"
PRIu32 " at %" PRIx32 "\n",
type, rela.r_offset);
}
}
return 0;
}
int main(int argc, char **argv)
{
FILE *f;
int ret;
uint64_t file_size;
if (argc != 3) {
fprintf(stderr, "Statically apply ELF rela relocations\n");
fprintf(stderr, "Usage: %s <bin file> <u-boot ELF>\n",
argv[0]);
return 1;
}
ret = decode_elf(argv);
if (ret) {
fprintf(stderr, "ELF decoding failed\n");
return ret;
}
if (rela_start > rela_end || rela_start < text_base) {
fprintf(stderr, "%s: bad rela bounds\n", argv[0]);
return 3;
}
rela_start -= text_base;
rela_end -= text_base;
dyn_start -= text_base;
f = fopen(argv[1], "r+b");
if (!f) {
fprintf(stderr, "%s: Cannot open %s: %s\n",
argv[0], argv[1], strerror(errno));
return 2;
}
fseek(f, 0, SEEK_END);
file_size = ftell(f);
rewind(f);
if (rela_end > file_size) {
// Most likely compiler inserted some section that didn't get
// objcopy-ed into the final binary
rela_end = file_size;
}
if (ei_class == 2)
ret = rela_elf64(argv, f);
else
ret = rela_elf32(argv, f);
if (fclose(f) < 0) {
fprintf(stderr, "%s: %s: close failed: %s\n",
argv[0], argv[1], strerror(errno));
return 4;
}
return ret;
}
Reference in New Issue View Git Blame Copy Permalink