contrib/elftoolchain/libelf/gelf_rela.c

   1 /*-
   2  * Copyright (c) 2006,2008 Joseph Koshy
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <assert.h>
  28 #include <gelf.h>
  29 #include <limits.h>
  30 #include <stdint.h>
  31
  32 #include "_libelf.h"
  33
  34 ELFTC_VCSID("$Id: gelf_rela.c 3177 2015-03-30 18:19:41Z emaste $");
  35
  36 GElf_Rela *
  37 gelf_getrela(Elf_Data *ed, int ndx, GElf_Rela *dst)
  38 {
  39         int ec;
  40         Elf *e;
  41         size_t msz;
  42         Elf_Scn *scn;
  43         uint32_t sh_type;
  44         Elf32_Rela *rela32;
  45         Elf64_Rela *rela64;
  46         struct _Libelf_Data *d;
  47
  48         d = (struct _Libelf_Data *) ed;
  49
  50         if (d == NULL || ndx < 0 || dst == NULL ||
  51             (scn = d->d_scn) == NULL ||
  52             (e = scn->s_elf) == NULL) {
  53                 LIBELF_SET_ERROR(ARGUMENT, 0);
  54                 return (NULL);
  55         }
  56
  57         ec = e->e_class;
  58         assert(ec == ELFCLASS32 || ec == ELFCLASS64);
  59
  60         if (ec == ELFCLASS32)
  61                 sh_type = scn->s_shdr.s_shdr32.sh_type;
  62         else
  63                 sh_type = scn->s_shdr.s_shdr64.sh_type;
  64
  65         if (_libelf_xlate_shtype(sh_type) != ELF_T_RELA) {
  66                 LIBELF_SET_ERROR(ARGUMENT, 0);
  67                 return (NULL);
  68         }
  69
  70         msz = _libelf_msize(ELF_T_RELA, ec, e->e_version);
  71
  72         assert(msz > 0);
  73         assert(ndx >= 0);
  74
  75         if (msz * (size_t) ndx >= d->d_data.d_size) {
  76                 LIBELF_SET_ERROR(ARGUMENT, 0);
  77                 return (NULL);
  78         }
  79
  80         if (ec == ELFCLASS32) {
  81                 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx;
  82
  83                 dst->r_offset = (Elf64_Addr) rela32->r_offset;
  84                 dst->r_info   = ELF64_R_INFO(
  85                     (Elf64_Xword) ELF32_R_SYM(rela32->r_info),
  86                     ELF32_R_TYPE(rela32->r_info));
  87                 dst->r_addend = (Elf64_Sxword) rela32->r_addend;
  88
  89         } else {
  90
  91                 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx;
  92
  93                 *dst = *rela64;
  94         }
  95
  96         return (dst);
  97 }
  98
  99 int
 100 gelf_update_rela(Elf_Data *ed, int ndx, GElf_Rela *dr)
 101 {
 102         int ec;
 103         Elf *e;
 104         size_t msz;
 105         Elf_Scn *scn;
 106         uint32_t sh_type;
 107         Elf32_Rela *rela32;
 108         Elf64_Rela *rela64;
 109         struct _Libelf_Data *d;
 110
 111         d = (struct _Libelf_Data *) ed;
 112
 113         if (d == NULL || ndx < 0 || dr == NULL ||
 114             (scn = d->d_scn) == NULL ||
 115             (e = scn->s_elf) == NULL) {
 116                 LIBELF_SET_ERROR(ARGUMENT, 0);
 117                 return (0);
 118         }
 119
 120         ec = e->e_class;
 121         assert(ec == ELFCLASS32 || ec == ELFCLASS64);
 122
 123         if (ec == ELFCLASS32)
 124                 sh_type = scn->s_shdr.s_shdr32.sh_type;
 125         else
 126                 sh_type = scn->s_shdr.s_shdr64.sh_type;
 127
 128         if (_libelf_xlate_shtype(sh_type) != ELF_T_RELA) {
 129                 LIBELF_SET_ERROR(ARGUMENT, 0);
 130                 return (0);
 131         }
 132
 133         msz = _libelf_msize(ELF_T_RELA, ec, e->e_version);
 134
 135         assert(msz > 0);
 136         assert(ndx >= 0);
 137
 138         if (msz * (size_t) ndx >= d->d_data.d_size) {
 139                 LIBELF_SET_ERROR(ARGUMENT, 0);
 140                 return (0);
 141         }
 142
 143         if (ec == ELFCLASS32) {
 144                 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx;
 145
 146                 LIBELF_COPY_U32(rela32, dr, r_offset);
 147
 148                 if (ELF64_R_SYM(dr->r_info) > ELF32_R_SYM(~0UL) ||
 149                     ELF64_R_TYPE(dr->r_info) > ELF32_R_TYPE(~0U)) {
 150                         LIBELF_SET_ERROR(RANGE, 0);
 151                         return (0);
 152                 }
 153                 rela32->r_info = ELF32_R_INFO(
 154                         (Elf32_Word) ELF64_R_SYM(dr->r_info),
 155                         (Elf32_Word) ELF64_R_TYPE(dr->r_info));
 156
 157                 LIBELF_COPY_S32(rela32, dr, r_addend);
 158         } else {
 159                 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx;
 160
 161                 *rela64 = *dr;
 162         }
 163
 164         return (1);
 165 }