1134362Siedowse/*- 2330449Seadler * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3330449Seadler * 4134362Siedowse * Copyright (c) 2003 Jake Burkholder. 5134362Siedowse * Copyright 1996-1998 John D. Polstra. 6134362Siedowse * All rights reserved. 7134362Siedowse * 8134362Siedowse * Redistribution and use in source and binary forms, with or without 9134362Siedowse * modification, are permitted provided that the following conditions 10134362Siedowse * are met: 11134362Siedowse * 1. Redistributions of source code must retain the above copyright 12134362Siedowse * notice, this list of conditions and the following disclaimer. 13134362Siedowse * 2. Redistributions in binary form must reproduce the above copyright 14134362Siedowse * notice, this list of conditions and the following disclaimer in the 15134362Siedowse * documentation and/or other materials provided with the distribution. 16134362Siedowse * 17134362Siedowse * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18134362Siedowse * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19134362Siedowse * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20134362Siedowse * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21134362Siedowse * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22134362Siedowse * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23134362Siedowse * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24134362Siedowse * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25134362Siedowse * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26134362Siedowse * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27134362Siedowse * SUCH DAMAGE. 28134362Siedowse * 29134362Siedowse * $FreeBSD: stable/11/usr.sbin/kldxref/ef_amd64.c 330449 2018-03-05 07:26:05Z eadler $ 30134362Siedowse */ 31134362Siedowse 32134362Siedowse#include <sys/types.h> 33134362Siedowse#include <machine/elf.h> 34134362Siedowse 35134362Siedowse#include <err.h> 36134362Siedowse#include <errno.h> 37134362Siedowse 38134362Siedowse#include "ef.h" 39134362Siedowse 40134362Siedowse/* 41134450Siedowse * Apply relocations to the values we got from the file. `relbase' is the 42134450Siedowse * target relocation address of the section, and `dataoff' is the target 43134450Siedowse * relocation address of the data in `dest'. 44134362Siedowse */ 45134362Siedowseint 46134450Siedowseef_reloc(struct elf_file *ef, const void *reldata, int reltype, Elf_Off relbase, 47134450Siedowse Elf_Off dataoff, size_t len, void *dest) 48134362Siedowse{ 49134362Siedowse Elf64_Addr *where, val; 50134362Siedowse Elf32_Addr *where32, val32; 51134362Siedowse Elf_Addr addend, addr; 52153504Smarcel Elf_Size rtype, symidx; 53134362Siedowse const Elf_Rel *rel; 54134362Siedowse const Elf_Rela *rela; 55134362Siedowse 56134450Siedowse switch (reltype) { 57134362Siedowse case EF_RELOC_REL: 58134450Siedowse rel = (const Elf_Rel *)reldata; 59134450Siedowse where = (Elf_Addr *)(dest + relbase + rel->r_offset - dataoff); 60134450Siedowse addend = 0; 61134362Siedowse rtype = ELF_R_TYPE(rel->r_info); 62134362Siedowse symidx = ELF_R_SYM(rel->r_info); 63134362Siedowse break; 64134362Siedowse case EF_RELOC_RELA: 65134450Siedowse rela = (const Elf_Rela *)reldata; 66134450Siedowse where = (Elf_Addr *)(dest + relbase + rela->r_offset - dataoff); 67134362Siedowse addend = rela->r_addend; 68134362Siedowse rtype = ELF_R_TYPE(rela->r_info); 69134362Siedowse symidx = ELF_R_SYM(rela->r_info); 70134362Siedowse break; 71134362Siedowse default: 72134362Siedowse return (EINVAL); 73134362Siedowse } 74134362Siedowse 75134362Siedowse if ((char *)where < (char *)dest || (char *)where >= (char *)dest + len) 76134362Siedowse return (0); 77134362Siedowse 78134450Siedowse if (reltype == EF_RELOC_REL) { 79134362Siedowse /* Addend is 32 bit on 32 bit relocs */ 80134362Siedowse switch (rtype) { 81134362Siedowse case R_X86_64_PC32: 82134362Siedowse case R_X86_64_32S: 83134362Siedowse addend = *(Elf32_Addr *)where; 84134362Siedowse break; 85134362Siedowse default: 86134362Siedowse addend = *where; 87134362Siedowse break; 88134362Siedowse } 89134362Siedowse } 90134362Siedowse 91134362Siedowse switch (rtype) { 92134362Siedowse case R_X86_64_NONE: /* none */ 93134362Siedowse break; 94134362Siedowse case R_X86_64_64: /* S + A */ 95134362Siedowse addr = EF_SYMADDR(ef, symidx); 96134362Siedowse val = addr + addend; 97134362Siedowse *where = val; 98134362Siedowse break; 99134362Siedowse case R_X86_64_32S: /* S + A sign extend */ 100134362Siedowse addr = EF_SYMADDR(ef, symidx); 101134362Siedowse val32 = (Elf32_Addr)(addr + addend); 102134362Siedowse where32 = (Elf32_Addr *)where; 103134362Siedowse *where32 = val32; 104134362Siedowse break; 105134362Siedowse case R_X86_64_GLOB_DAT: /* S */ 106134362Siedowse addr = EF_SYMADDR(ef, symidx); 107134362Siedowse *where = addr; 108134362Siedowse break; 109134362Siedowse case R_X86_64_RELATIVE: /* B + A */ 110134450Siedowse addr = (Elf_Addr)addend + relbase; 111134362Siedowse val = addr; 112134362Siedowse *where = val; 113134362Siedowse break; 114134362Siedowse default: 115134362Siedowse warnx("unhandled relocation type %d", (int)rtype); 116134362Siedowse } 117134362Siedowse return (0); 118134362Siedowse} 119