/*
* Copyright (c) 2008 Jiri Svoboda
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup rtld rtld
* @brief
* @{
*/
/**
* @file
*/
#include <stdio.h>
#include <arch.h>
#include <elf_dyn.h>
#include <symbol.h>
#include <rtld.h>
void module_process_pre_arch(module_t *m)
{
/* Unused */
}
/**
* Process (fixup) all relocations in a relocation table.
*/
void rel_table_process(module_t *m, elf_rel_t *rt, size_t rt_size)
{
int i;
size_t rt_entries;
size_t r_offset;
elf_word r_info;
unsigned rel_type;
elf_word sym_idx;
uintptr_t sym_addr;
elf_symbol_t *sym_table;
elf_symbol_t *sym;
uint32_t *r_ptr;
char *str_tab;
elf_symbol_t *sym_def;
module_t *dest;
DPRINTF("parse relocation table\n");
sym_table = m->dyn.sym_tab;
rt_entries = rt_size / sizeof(elf_rel_t);
str_tab = m->dyn.str_tab;
DPRINTF("address: 0x%x, entries: %d\n", (uintptr_t)rt, rt_entries);
for (i = 0; i < rt_entries; ++i) {
// DPRINTF("symbol %d: ", i);
r_offset = rt[i].r_offset;
r_info = rt[i].r_info;
sym_idx = ELF32_R_SYM(r_info);
sym = &sym_table[sym_idx];
/* DPRINTF("name '%s', value 0x%x, size 0x%x\n",
str_tab + sym->st_name,
sym->st_value,
sym->st_size);
*/
rel_type = ELF32_R_TYPE(r_info);
r_ptr = (uint32_t *)(r_offset + m->bias);
if (sym->st_name != 0) {
// DPRINTF("rel_type: %x, rel_offset: 0x%x\n", rel_type, r_offset);
sym_def = symbol_def_find(str_tab + sym->st_name,
m, &dest);
// DPRINTF("dest name: '%s'\n", dest->dyn.soname);
// DPRINTF("dest bias: 0x%x\n", dest->bias);
if (sym_def) {
sym_addr = symbol_get_addr(sym_def, dest);
// DPRINTF("symbol definition found, addr=0x%x\n", sym_addr);
} else {
DPRINTF("symbol definition not found\n");
continue;
}
}
switch (rel_type) {
case R_386_GLOB_DAT:
case R_386_JUMP_SLOT:
// DPRINTF("fixup R_386_GLOB_DAT/JUMP_SLOT (b+v)\n");
*r_ptr = sym_addr;
break;
case R_386_32:
// DPRINTF("fixup R_386_32 (b+v+a)\n");
*r_ptr += sym_addr;
break;
case R_386_RELATIVE:
// DPRINTF("fixup R_386_RELATIVE (b+a)\n");
*r_ptr += m->bias;
break;
default:
printf("Unknown relocation type %d\n", rel_type
);
break;
}
}
}
void rela_table_process(module_t *m, elf_rela_t *rt, size_t rt_size)
{
/* Unused */
(void)m; (void)rt; (void)rt_size;
}
/** @}
*/