ef_i386.c revision 134362
1134362Siedowse/*- 2134362Siedowse * Copyright (c) 2003 Jake Burkholder. 3134362Siedowse * Copyright 1996-1998 John D. Polstra. 4134362Siedowse * All rights reserved. 5134362Siedowse * 6134362Siedowse * Redistribution and use in source and binary forms, with or without 7134362Siedowse * modification, are permitted provided that the following conditions 8134362Siedowse * are met: 9134362Siedowse * 1. Redistributions of source code must retain the above copyright 10134362Siedowse * notice, this list of conditions and the following disclaimer. 11134362Siedowse * 2. Redistributions in binary form must reproduce the above copyright 12134362Siedowse * notice, this list of conditions and the following disclaimer in the 13134362Siedowse * documentation and/or other materials provided with the distribution. 14134362Siedowse * 15134362Siedowse * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16134362Siedowse * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17134362Siedowse * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18134362Siedowse * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19134362Siedowse * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20134362Siedowse * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21134362Siedowse * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22134362Siedowse * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23134362Siedowse * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24134362Siedowse * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25134362Siedowse * SUCH DAMAGE. 26134362Siedowse * 27134362Siedowse * $FreeBSD: head/usr.sbin/kldxref/ef_i386.c 134362 2004-08-27 01:06:57Z iedowse $ 28134362Siedowse */ 29134362Siedowse 30134362Siedowse#include <sys/types.h> 31134362Siedowse#include <machine/elf.h> 32134362Siedowse 33134362Siedowse#include <err.h> 34134362Siedowse#include <errno.h> 35134362Siedowse#include <string.h> 36134362Siedowse 37134362Siedowse#include "ef.h" 38134362Siedowse 39134362Siedowse/* 40134362Siedowse * Apply relocations to the values we got from the file. 41134362Siedowse */ 42134362Siedowseint 43134362Siedowseef_reloc(struct elf_file *ef, const void *data, int type, Elf_Off offset, 44134362Siedowse size_t len, void *dest) 45134362Siedowse{ 46134362Siedowse Elf_Addr *where, addr, addend; 47134362Siedowse Elf_Word rtype, symidx; 48134362Siedowse const Elf_Rel *rel; 49134362Siedowse const Elf_Rela *rela; 50134362Siedowse 51134362Siedowse switch (type) { 52134362Siedowse case EF_RELOC_REL: 53134362Siedowse rel = (const Elf_Rel *)data; 54134362Siedowse where = (Elf_Addr *)(dest + rel->r_offset - offset); 55134362Siedowse rtype = ELF_R_TYPE(rel->r_info); 56134362Siedowse symidx = ELF_R_SYM(rel->r_info); 57134362Siedowse break; 58134362Siedowse case EF_RELOC_RELA: 59134362Siedowse rela = (const Elf_Rela *)data; 60134362Siedowse where = (Elf_Addr *)(dest + rela->r_offset - offset); 61134362Siedowse addend = rela->r_addend; 62134362Siedowse rtype = ELF_R_TYPE(rela->r_info); 63134362Siedowse symidx = ELF_R_SYM(rela->r_info); 64134362Siedowse break; 65134362Siedowse default: 66134362Siedowse return (EINVAL); 67134362Siedowse } 68134362Siedowse 69134362Siedowse if ((char *)where < (char *)dest || (char *)where >= (char *)dest + len) 70134362Siedowse return (0); 71134362Siedowse 72134362Siedowse if (type == EF_RELOC_REL) 73134362Siedowse addend = *where; 74134362Siedowse 75134362Siedowse switch (rtype) { 76134362Siedowse case R_386_RELATIVE: /* A + B */ 77134362Siedowse addr = (Elf_Addr)addend; 78134362Siedowse *where = addr; 79134362Siedowse break; 80134362Siedowse case R_386_32: /* S + A - P */ 81134362Siedowse addr = EF_SYMADDR(ef, symidx); 82134362Siedowse addr += addend; 83134362Siedowse *where = addr; 84134362Siedowse break; 85134362Siedowse case R_386_GLOB_DAT: /* S */ 86134362Siedowse addr = EF_SYMADDR(ef, symidx); 87134362Siedowse *where = addr; 88134362Siedowse break; 89134362Siedowse default: 90134362Siedowse warnx("unhandled relocation type %d", (int)rtype); 91134362Siedowse } 92134362Siedowse return (0); 93134362Siedowse} 94