external/bsd/libelf/dist/gelf_rel.c

   1 /*      $NetBSD: gelf_rel.c,v 1.2 2009/12/19 06:39:29 thorpej Exp $     */
   2
   3 /*-
   4  * Copyright (c) 2006 Joseph Koshy
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 /* __FBSDID("$FreeBSD: src/lib/libelf/gelf_rel.c,v 1.2.2.1.2.1 2009/10/25 01:10:29 kensmith Exp $"); */
  31
  32 #include <assert.h>
  33 #include <limits.h>
  34 #include <gelf.h>
  35
  36 #include "_libelf.h"
  37
  38 GElf_Rel *
  39 gelf_getrel(Elf_Data *d, int ndx, GElf_Rel *dst)
  40 {
  41         int ec;
  42         Elf *e;
  43         Elf_Scn *scn;
  44         Elf32_Rel *rel32;
  45         Elf64_Rel *rel64;
  46         size_t msz;
  47         uint32_t sh_type;
  48
  49         if (d == NULL || ndx < 0 || dst == NULL ||
  50             (scn = d->d_scn) == NULL ||
  51             (e = scn->s_elf) == NULL) {
  52                 LIBELF_SET_ERROR(ARGUMENT, 0);
  53                 return (NULL);
  54         }
  55
  56         ec = e->e_class;
  57         assert(ec == ELFCLASS32 || ec == ELFCLASS64);
  58
  59         if (ec == ELFCLASS32)
  60                 sh_type = scn->s_shdr.s_shdr32.sh_type;
  61         else
  62                 sh_type = scn->s_shdr.s_shdr64.sh_type;
  63
  64         if (_libelf_xlate_shtype(sh_type) != ELF_T_REL) {
  65                 LIBELF_SET_ERROR(ARGUMENT, 0);
  66                 return (NULL);
  67         }
  68
  69         msz = _libelf_msize(ELF_T_REL, ec, e->e_version);
  70
  71         assert(msz > 0);
  72
  73         if (msz * ndx >= d->d_size) {
  74                 LIBELF_SET_ERROR(ARGUMENT, 0);
  75                 return (NULL);
  76         }
  77
  78         if (ec == ELFCLASS32) {
  79                 rel32 = (Elf32_Rel *) d->d_buf + ndx;
  80
  81                 dst->r_offset = (Elf64_Addr) rel32->r_offset;
  82                 dst->r_info   = ELF64_R_INFO(
  83                     (Elf64_Xword) ELF32_R_SYM(rel32->r_info),
  84                     ELF32_R_TYPE(rel32->r_info));
  85
  86         } else {
  87
  88                 rel64 = (Elf64_Rel *) d->d_buf + ndx;
  89
  90                 *dst = *rel64;
  91         }
  92
  93         return (dst);
  94 }
  95
  96 int
  97 gelf_update_rel(Elf_Data *d, int ndx, GElf_Rel *dr)
  98 {
  99         int ec;
 100         Elf *e;
 101         Elf_Scn *scn;
 102         Elf32_Rel *rel32;
 103         Elf64_Rel *rel64;
 104         size_t msz;
 105         uint32_t sh_type;
 106
 107         if (d == NULL || ndx < 0 || dr == NULL ||
 108             (scn = d->d_scn) == NULL ||
 109             (e = scn->s_elf) == NULL) {
 110                 LIBELF_SET_ERROR(ARGUMENT, 0);
 111                 return (0);
 112         }
 113
 114         ec = e->e_class;
 115         assert(ec == ELFCLASS32 || ec == ELFCLASS64);
 116
 117         if (ec == ELFCLASS32)
 118                 sh_type = scn->s_shdr.s_shdr32.sh_type;
 119         else
 120                 sh_type = scn->s_shdr.s_shdr64.sh_type;
 121
 122         if (_libelf_xlate_shtype(sh_type) != ELF_T_REL) {
 123                 LIBELF_SET_ERROR(ARGUMENT, 0);
 124                 return (0);
 125         }
 126
 127         msz = _libelf_msize(ELF_T_REL, ec, e->e_version);
 128         assert(msz > 0);
 129
 130         if (msz * ndx >= d->d_size) {
 131                 LIBELF_SET_ERROR(ARGUMENT, 0);
 132                 return (0);
 133         }
 134
 135         if (ec == ELFCLASS32) {
 136                 rel32 = (Elf32_Rel *) d->d_buf + ndx;
 137
 138                 LIBELF_COPY_U32(rel32, dr, r_offset);
 139
 140                 if (ELF64_R_SYM(dr->r_info) > ELF32_R_SYM(~0UL) ||
 141                     ELF64_R_TYPE(dr->r_info) > ELF32_R_TYPE(~0U)) {
 142                         LIBELF_SET_ERROR(RANGE, 0);
 143                         return (0);
 144                 }
 145                 rel32->r_info = ELF32_R_INFO(ELF64_R_SYM(dr->r_info),
 146                     ELF64_R_TYPE(dr->r_info));
 147         } else {
 148                 rel64 = (Elf64_Rel *) d->d_buf + ndx;
 149
 150                 *rel64 = *dr;
 151         }
 152
 153         return (1);
 154 }