usr/src/boot/sys/boot/common/reloc_elf.c

   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
  30 #include <sys/cdefs.h>
  31 __FBSDID("$FreeBSD$");
  32
  33 #include <sys/types.h>
  34 #include <machine/elf.h>
  35
  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 #ifdef __sparc__
  56         Elf_Size w;
  57         const Elf_Rela *a;
  58
  59         switch (reltype) {
  60         case ELF_RELOC_RELA:
  61                 a = reldata;
  62                  if (relbase + a->r_offset >= dataaddr &&
  63                      relbase + a->r_offset < dataaddr + len) {
  64                         switch (ELF_R_TYPE(a->r_info)) {
  65                         case R_SPARC_RELATIVE:
  66                                 w = relbase + a->r_addend;
  67                                 bcopy(&w, (u_char *)data + (relbase +
  68                                     a->r_offset - dataaddr), sizeof(w));
  69                                 break;
  70                         default:
  71                                 printf("\nunhandled relocation type %u\n",
  72                                     (u_int)ELF_R_TYPE(a->r_info));
  73                                 return (EFTYPE);
  74                         }
  75                 }
  76                 break;
  77         }
  78
  79         return (0);
  80 #elif (defined(__i386__) || defined(__amd64__)) && __ELF_WORD_SIZE == 64
  81         Elf64_Addr *where, val;
  82         Elf_Addr addend, addr;
  83         Elf_Size rtype, symidx;
  84         const Elf_Rel *rel;
  85         const Elf_Rela *rela;
  86
  87         switch (reltype) {
  88         case ELF_RELOC_REL:
  89                 rel = (const Elf_Rel *)reldata;
  90                 where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
  91                     dataaddr);
  92                 addend = 0;
  93                 rtype = ELF_R_TYPE(rel->r_info);
  94                 symidx = ELF_R_SYM(rel->r_info);
  95                 addend = 0;
  96                 break;
  97         case ELF_RELOC_RELA:
  98                 rela = (const Elf_Rela *)reldata;
  99                 where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
 100                     dataaddr);
 101                 addend = rela->r_addend;
 102                 rtype = ELF_R_TYPE(rela->r_info);
 103                 symidx = ELF_R_SYM(rela->r_info);
 104                 break;
 105         default:
 106                 return (EINVAL);
 107         }
 108
 109         if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
 110                 return (0);
 111
 112         if (reltype == ELF_RELOC_REL)
 113                 addend = *where;
 114
 115 /* XXX, definitions not available on i386. */
 116 #define R_X86_64_64             1
 117 #define R_X86_64_RELATIVE       8
 118
 119         switch (rtype) {
 120         case R_X86_64_64:               /* S + A */
 121                 addr = symaddr(ef, symidx);
 122                 if (addr == 0)
 123                         return (ESRCH);
 124                 val = addr + addend;
 125                 *where = val;
 126                 break;
 127         case R_X86_64_RELATIVE:
 128                 addr = (Elf_Addr)addend + relbase;
 129                 val = addr;
 130                 *where = val;
 131                 break;
 132         default:
 133                 printf("\nunhandled relocation type %u\n", (u_int)rtype);
 134                 return (EFTYPE);
 135         }
 136
 137         return (0);
 138 #elif defined(__i386__) && __ELF_WORD_SIZE == 32
 139         Elf_Addr addend, addr, *where, val;
 140         Elf_Size rtype, symidx;
 141         const Elf_Rel *rel;
 142         const Elf_Rela *rela;
 143
 144         switch (reltype) {
 145         case ELF_RELOC_REL:
 146                 rel = (const Elf_Rel *)reldata;
 147                 where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
 148                     dataaddr);
 149                 addend = 0;
 150                 rtype = ELF_R_TYPE(rel->r_info);
 151                 symidx = ELF_R_SYM(rel->r_info);
 152                 addend = 0;
 153                 break;
 154         case ELF_RELOC_RELA:
 155                 rela = (const Elf_Rela *)reldata;
 156                 where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
 157                     dataaddr);
 158                 addend = rela->r_addend;
 159                 rtype = ELF_R_TYPE(rela->r_info);
 160                 symidx = ELF_R_SYM(rela->r_info);
 161                 break;
 162         default:
 163                 return (EINVAL);
 164         }
 165
 166         if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
 167                 return (0);
 168
 169         if (reltype == ELF_RELOC_REL)
 170                 addend = *where;
 171
 172 /* XXX, definitions not available on amd64. */
 173 #define R_386_32        1       /* Add symbol value. */
 174 #define R_386_GLOB_DAT  6       /* Set GOT entry to data address. */
 175 #define R_386_RELATIVE  8       /* Add load address of shared object. */
 176
 177         switch (rtype) {
 178         case R_386_RELATIVE:
 179                 addr = addend + relbase;
 180                 *where = addr;
 181                 break;
 182         case R_386_32:          /* S + A */
 183                 addr = symaddr(ef, symidx);
 184                 if (addr == 0)
 185                         return (ESRCH);
 186                 val = addr + addend;
 187                 *where = val;
 188                 break;
 189         default:
 190                 printf("\nunhandled relocation type %u\n", (u_int)rtype);
 191                 return (EFTYPE);
 192         }
 193
 194         return (0);
 195 #elif defined(__powerpc__)
 196         Elf_Size w;
 197         const Elf_Rela *rela;
 198
 199         switch (reltype) {
 200         case ELF_RELOC_RELA:
 201                 rela = reldata;
 202                 if (relbase + rela->r_offset >= dataaddr &&
 203                     relbase + rela->r_offset < dataaddr + len) {
 204                         switch (ELF_R_TYPE(rela->r_info)) {
 205                         case R_PPC_RELATIVE:
 206                                 w = relbase + rela->r_addend;
 207                                 bcopy(&w, (u_char *)data + (relbase +
 208                                       rela->r_offset - dataaddr), sizeof(w));
 209                                 break;
 210                         default:
 211                                 printf("\nunhandled relocation type %u\n",
 212                                        (u_int)ELF_R_TYPE(rela->r_info));
 213                                 return (EFTYPE);
 214                         }
 215                 }
 216                 break;
 217         }
 218
 219         return (0);
 220 #else
 221         (void)ef;
 222         (void)symaddr;
 223         (void)reldata;
 224         (void)reltype;
 225         (void)relbase;
 226         (void)dataaddr;
 227         (void)data;
 228         (void)len;
 229         return (EOPNOTSUPP);
 230 #endif
 231 }