lib/libelf/gelf_symshndx.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 <sys/cdefs.h>
  28
  29 #include <assert.h>
  30 #include <gelf.h>
  31
  32 #include "_libelf.h"
  33
  34 LIBELF_VCSID("$Id$");
  35
  36 GElf_Sym *
  37 gelf_getsymshndx(Elf_Data *d, Elf_Data *id, int ndx, GElf_Sym *dst,
  38     Elf32_Word *shindex)
  39 {
  40         int ec;
  41         Elf *e;
  42         Elf_Scn *scn;
  43         size_t msz;
  44         uint32_t sh_type;
  45
  46         if (gelf_getsym(d, ndx, dst) == 0)
  47                 return (NULL);
  48
  49         if (id == NULL || (scn = id->d_scn) == NULL ||
  50             (e = scn->s_elf) == NULL || (e != d->d_scn->s_elf) ||
  51             shindex == 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_WORD ||
  65            id->d_type != ELF_T_WORD) {
  66                 LIBELF_SET_ERROR(ARGUMENT, 0);
  67                 return (NULL);
  68         }
  69
  70         msz = _libelf_msize(ELF_T_WORD, ec, e->e_version);
  71
  72         assert(msz > 0);
  73
  74         if (msz * ndx >= id->d_size) {
  75                 LIBELF_SET_ERROR(ARGUMENT, 0);
  76                 return (NULL);
  77         }
  78
  79         *shindex = ((Elf32_Word *) id->d_buf)[ndx];
  80
  81         return (dst);
  82 }
  83
  84 int
  85 gelf_update_symshndx(Elf_Data *d, Elf_Data *id, int ndx, GElf_Sym *gs,
  86     Elf32_Word xindex)
  87 {
  88         int ec;
  89         Elf *e;
  90         Elf_Scn *scn;
  91         size_t msz;
  92         uint32_t sh_type;
  93
  94         if (gelf_update_sym(d, ndx, gs) == 0)
  95                 return (0);
  96
  97         if (id == NULL || (scn = id->d_scn) == NULL ||
  98             (e = scn->s_elf) == NULL || (e != d->d_scn->s_elf)) {
  99                 LIBELF_SET_ERROR(ARGUMENT, 0);
 100                 return (0);
 101         }
 102
 103         ec = e->e_class;
 104         assert(ec == ELFCLASS32 || ec == ELFCLASS64);
 105
 106         if (ec == ELFCLASS32)
 107                 sh_type = scn->s_shdr.s_shdr32.sh_type;
 108         else
 109                 sh_type = scn->s_shdr.s_shdr64.sh_type;
 110
 111         if (_libelf_xlate_shtype(sh_type) != ELF_T_WORD ||
 112             d->d_type != ELF_T_WORD) {
 113                 LIBELF_SET_ERROR(ARGUMENT, 0);
 114                 return (0);
 115         }
 116
 117         msz = _libelf_msize(ELF_T_WORD, ec, e->e_version);
 118         assert(msz > 0);
 119
 120         if (msz * ndx >= id->d_size) {
 121                 LIBELF_SET_ERROR(ARGUMENT, 0);
 122                 return (0);
 123         }
 124
 125         *(((Elf32_Word *) id->d_buf) + ndx) = xindex;
 126
 127         return (1);
 128 }