1 /*- 2 * Copyright (c) 2003 Jake Burkholder. 3 * Copyright 1996-1998 John D. Polstra. 4 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org> 5 * Copyright (c) 1998 Peter Wemm <peter@freebsd.org> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD: src/sys/boot/common/reloc_elf.c,v 1.2 2005/12/18 04:52:35 marcel Exp $ 30 */ 31 32 #include <sys/types.h> 33 #include <machine/elf.h> 34 35 #include <errno.h> 36 #include <stand.h> 37 38 #define FREEBSD_ELF 39 #include <link.h> 40 41 #include "bootstrap.h" 42 43 #define COPYOUT(s,d,l) archsw.arch_copyout((vm_offset_t)(s), d, l) 44 45 /* 46 * Apply a single intra-module relocation to the data. `relbase' is the 47 * target relocation base for the section (i.e. it corresponds to where 48 * r_offset == 0). `dataaddr' is the relocated address corresponding to 49 * the start of the data, and `len' is the number of bytes. 50 */ 51 int 52 __elfN(reloc)(struct elf_file *ef, symaddr_fn *symaddr, const void *reldata, 53 int reltype, Elf_Addr relbase, Elf_Addr dataaddr, void *data, size_t len) 54 { 55 #if (defined(__x86_64__) || defined(__i386__)) && __ELF_WORD_SIZE == 64 56 Elf64_Addr *where, val; 57 Elf_Addr addend, addr; 58 Elf_Size rtype, symidx; 59 const Elf_Rel *rel; 60 const Elf_Rela *rela; 61 62 switch (reltype) { 63 case ELF_RELOC_REL: 64 rel = (const Elf_Rel *)reldata; 65 where = (Elf64_Addr *)((char *)data + relbase + rel->r_offset - 66 dataaddr); 67 addend = 0; 68 rtype = ELF_R_TYPE(rel->r_info); 69 symidx = ELF_R_SYM(rel->r_info); 70 addend = 0; 71 break; 72 case ELF_RELOC_RELA: 73 rela = (const Elf_Rela *)reldata; 74 where = (Elf64_Addr *)((char *)data + relbase + rela->r_offset - 75 dataaddr); 76 addend = rela->r_addend; 77 rtype = ELF_R_TYPE(rela->r_info); 78 symidx = ELF_R_SYM(rela->r_info); 79 break; 80 default: 81 return (EINVAL); 82 } 83 84 if ((char *)where < (char *)data || (char *)where >= (char *)data + len) 85 return (0); 86 87 if (reltype == ELF_RELOC_REL) 88 addend = *where; 89 90 /* XXX, definitions not available on i386. */ 91 #define R_X86_64_64 1 92 #define R_X86_64_RELATIVE 8 93 94 switch (rtype) { 95 case R_X86_64_64: /* S + A */ 96 addr = symaddr(ef, symidx); 97 if (addr == 0) 98 return (ESRCH); 99 val = addr + addend; 100 *where = val; 101 break; 102 case R_X86_64_RELATIVE: 103 addr = (Elf_Addr)addend + relbase; 104 val = addr; 105 *where = val; 106 break; 107 default: 108 printf("\nunhandled relocation type %u\n", (u_int)rtype); 109 return (EFTYPE); 110 } 111 112 return (0); 113 #elif defined(__i386__) && __ELF_WORD_SIZE == 32 114 Elf_Addr addend, addr, *where, val; 115 Elf_Size rtype, symidx; 116 const Elf_Rel *rel; 117 const Elf_Rela *rela; 118 119 switch (reltype) { 120 case ELF_RELOC_REL: 121 rel = (const Elf_Rel *)reldata; 122 where = (Elf_Addr *)((char *)data + relbase + rel->r_offset - 123 dataaddr); 124 addend = 0; 125 rtype = ELF_R_TYPE(rel->r_info); 126 symidx = ELF_R_SYM(rel->r_info); 127 addend = 0; 128 break; 129 case ELF_RELOC_RELA: 130 rela = (const Elf_Rela *)reldata; 131 where = (Elf_Addr *)((char *)data + relbase + rela->r_offset - 132 dataaddr); 133 addend = rela->r_addend; 134 rtype = ELF_R_TYPE(rela->r_info); 135 symidx = ELF_R_SYM(rela->r_info); 136 break; 137 default: 138 return (EINVAL); 139 } 140 141 if ((char *)where < (char *)data || (char *)where >= (char *)data + len) 142 return (0); 143 144 if (reltype == ELF_RELOC_REL) 145 addend = *where; 146 147 /* XXX, definitions not available on x86_64. */ 148 #define R_386_32 1 /* Add symbol value. */ 149 #define R_386_GLOB_DAT 6 /* Set GOT entry to data address. */ 150 #define R_386_RELATIVE 8 /* Add load address of shared object. */ 151 152 switch (rtype) { 153 case R_386_RELATIVE: 154 addr = addend + relbase; 155 *where = addr; 156 break; 157 case R_386_32: /* S + A */ 158 addr = symaddr(ef, symidx); 159 if (addr == 0) 160 return (ESRCH); 161 val = addr + addend; 162 *where = val; 163 break; 164 default: 165 printf("\nunhandled relocation type %u\n", (u_int)rtype); 166 return (EFTYPE); 167 } 168 169 return (0); 170 #else 171 return (EOPNOTSUPP); 172 #endif 173 } 174