external/bsd/elftoolchain/dist/libelf/libelf_phdr.c

   1 /*      $NetBSD: libelf_phdr.c,v 1.2 2014/03/09 16:58:04 christos Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2006,2008 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 #if HAVE_NBTOOL_CONFIG_H
  30 # include "nbtool_config.h"
  31 #endif
  32
  33 #include <sys/cdefs.h>
  34
  35 #include <assert.h>
  36 #include <gelf.h>
  37 #include <libelf.h>
  38 #include <stdlib.h>
  39
  40 #include "_libelf.h"
  41
  42 __RCSID("$NetBSD: libelf_phdr.c,v 1.2 2014/03/09 16:58:04 christos Exp $");
  43 ELFTC_VCSID("Id: libelf_phdr.c 2931 2013-03-23 11:41:07Z jkoshy ");
  44
  45 void *
  46 _libelf_getphdr(Elf *e, int ec)
  47 {
  48         size_t phnum;
  49         size_t fsz, msz;
  50         uint64_t phoff;
  51         Elf32_Ehdr *eh32;
  52         Elf64_Ehdr *eh64;
  53         void *ehdr, *phdr;
  54         int (*xlator)(char *_d, size_t _dsz, char *_s, size_t _c, int _swap);
  55
  56         assert(ec == ELFCLASS32 || ec == ELFCLASS64);
  57
  58         if (e == NULL) {
  59                 LIBELF_SET_ERROR(ARGUMENT, 0);
  60                 return (NULL);
  61         }
  62
  63         if ((phdr = (ec == ELFCLASS32 ?
  64                  (void *) e->e_u.e_elf.e_phdr.e_phdr32 :
  65                  (void *) e->e_u.e_elf.e_phdr.e_phdr64)) != NULL)
  66                 return (phdr);
  67
  68         /*
  69          * Check the PHDR related fields in the EHDR for sanity.
  70          */
  71
  72         if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL)
  73                 return (NULL);
  74
  75         phnum = e->e_u.e_elf.e_nphdr;
  76
  77         if (ec == ELFCLASS32) {
  78                 eh32      = (Elf32_Ehdr *) ehdr;
  79                 phoff     = (uint64_t) eh32->e_phoff;
  80         } else {
  81                 eh64      = (Elf64_Ehdr *) ehdr;
  82                 phoff     = (uint64_t) eh64->e_phoff;
  83         }
  84
  85         fsz = gelf_fsize(e, ELF_T_PHDR, phnum, e->e_version);
  86
  87         assert(fsz > 0);
  88
  89         if ((uint64_t) e->e_rawsize < (phoff + fsz)) {
  90                 LIBELF_SET_ERROR(HEADER, 0);
  91                 return (NULL);
  92         }
  93
  94         msz = _libelf_msize(ELF_T_PHDR, ec, EV_CURRENT);
  95
  96         assert(msz > 0);
  97
  98         if ((phdr = calloc(phnum, msz)) == NULL) {
  99                 LIBELF_SET_ERROR(RESOURCE, 0);
 100                 return (NULL);
 101         }
 102
 103         if (ec == ELFCLASS32)
 104                 e->e_u.e_elf.e_phdr.e_phdr32 = phdr;
 105         else
 106                 e->e_u.e_elf.e_phdr.e_phdr64 = phdr;
 107
 108
 109         xlator = _libelf_get_translator(ELF_T_PHDR, ELF_TOMEMORY, ec);
 110         (*xlator)(phdr, phnum * msz, e->e_rawfile + phoff, phnum,
 111             e->e_byteorder != _libelf_host_byteorder());
 112
 113         return (phdr);
 114 }
 115
 116 void *
 117 _libelf_newphdr(Elf *e, int ec, size_t count)
 118 {
 119         void *ehdr, *newphdr, *oldphdr;
 120         size_t msz;
 121
 122         if (e == NULL) {
 123                 LIBELF_SET_ERROR(ARGUMENT, 0);
 124                 return (NULL);
 125         }
 126
 127         if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL) {
 128                 LIBELF_SET_ERROR(SEQUENCE, 0);
 129                 return (NULL);
 130         }
 131
 132         assert(e->e_class == ec);
 133         assert(ec == ELFCLASS32 || ec == ELFCLASS64);
 134         assert(e->e_version == EV_CURRENT);
 135
 136         msz = _libelf_msize(ELF_T_PHDR, ec, e->e_version);
 137
 138         assert(msz > 0);
 139
 140         newphdr = NULL;
 141         if (count > 0 && (newphdr = calloc(count, msz)) == NULL) {
 142                 LIBELF_SET_ERROR(RESOURCE, 0);
 143                 return (NULL);
 144         }
 145
 146         if (ec == ELFCLASS32) {
 147                 if ((oldphdr = (void *) e->e_u.e_elf.e_phdr.e_phdr32) != NULL)
 148                         free(oldphdr);
 149                 e->e_u.e_elf.e_phdr.e_phdr32 = (Elf32_Phdr *) newphdr;
 150         } else {
 151                 if ((oldphdr = (void *) e->e_u.e_elf.e_phdr.e_phdr64) != NULL)
 152                         free(oldphdr);
 153                 e->e_u.e_elf.e_phdr.e_phdr64 = (Elf64_Phdr *) newphdr;
 154         }
 155
 156         e->e_u.e_elf.e_nphdr = count;
 157
 158         elf_flagphdr(e, ELF_C_SET, ELF_F_DIRTY);
 159
 160         return (newphdr);
 161 }