contrib/elftoolchain/libelf/libelf_memory.c

   1 /*-
   2  * Copyright (c) 2011 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 <ar.h>
  28 #include <assert.h>
  29 #include <string.h>
  30 #include <libelf.h>
  31
  32 #include "_libelf.h"
  33
  34 ELFTC_VCSID("$Id: libelf_memory.c 3013 2014-03-23 06:16:59Z jkoshy $");
  35
  36 /*
  37  * Create an ELF descriptor for a memory image, optionally reporting
  38  * parse errors.
  39  */
  40
  41 Elf *
  42 _libelf_memory(unsigned char *image, size_t sz, int reporterror)
  43 {
  44         Elf *e;
  45         int e_class;
  46         enum Elf_Error error;
  47         unsigned int e_byteorder, e_version;
  48
  49         assert(image != NULL);
  50         assert(sz > 0);
  51
  52         if ((e = _libelf_allocate_elf()) == NULL)
  53                 return (NULL);
  54
  55         e->e_cmd = ELF_C_READ;
  56         e->e_rawfile = image;
  57         e->e_rawsize = sz;
  58
  59 #undef  LIBELF_IS_ELF
  60 #define LIBELF_IS_ELF(P) ((P)[EI_MAG0] == ELFMAG0 &&            \
  61         (P)[EI_MAG1] == ELFMAG1 && (P)[EI_MAG2] == ELFMAG2 &&   \
  62         (P)[EI_MAG3] == ELFMAG3)
  63
  64         if (sz > EI_NIDENT && LIBELF_IS_ELF(image)) {
  65                 e_byteorder = image[EI_DATA];
  66                 e_class     = image[EI_CLASS];
  67                 e_version   = image[EI_VERSION];
  68
  69                 error = ELF_E_NONE;
  70
  71                 if (e_version > EV_CURRENT)
  72                         error = ELF_E_VERSION;
  73                 else if ((e_byteorder != ELFDATA2LSB && e_byteorder !=
  74                     ELFDATA2MSB) || (e_class != ELFCLASS32 && e_class !=
  75                     ELFCLASS64))
  76                         error = ELF_E_HEADER;
  77
  78                 if (error != ELF_E_NONE) {
  79                         if (reporterror) {
  80                                 LIBELF_PRIVATE(error) = LIBELF_ERROR(error, 0);
  81                                 (void) _libelf_release_elf(e);
  82                                 return (NULL);
  83                         }
  84                 } else {
  85                         _libelf_init_elf(e, ELF_K_ELF);
  86
  87                         e->e_byteorder = e_byteorder;
  88                         e->e_class = e_class;
  89                         e->e_version = e_version;
  90                 }
  91         } else if (sz >= SARMAG &&
  92             strncmp((const char *) image, ARMAG, (size_t) SARMAG) == 0)
  93                 return (_libelf_ar_open(e, reporterror));
  94
  95         return (e);
  96 }