ext/libelf/elf_memory.c

   1 /*-
   2  * Copyright (c) 2006 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
  28 #include <ar.h>
  29 #include "libelf.h"
  30 #include <string.h>
  31
  32 #include "_libelf.h"
  33
  34 Elf *
  35 elf_memory(char *image, size_t sz)
  36 {
  37         Elf *e;
  38
  39         if (LIBELF_PRIVATE(version) == EV_NONE) {
  40                 LIBELF_SET_ERROR(SEQUENCE, 0);
  41                 return (NULL);
  42         }
  43
  44         if (image == NULL || sz == 0) {
  45                 LIBELF_SET_ERROR(ARGUMENT, 0);
  46                 return (NULL);
  47         }
  48
  49         if ((e = _libelf_allocate_elf()) == NULL)
  50                 return (NULL);
  51
  52         e->e_cmd = ELF_C_READ;
  53         e->e_rawfile = image;
  54         e->e_rawsize = sz;
  55
  56 #undef  LIBELF_IS_ELF
  57 #define LIBELF_IS_ELF(P) ((P)[EI_MAG0] == ELFMAG0 &&            \
  58         (P)[EI_MAG1] == ELFMAG1 && (P)[EI_MAG2] == ELFMAG2 &&   \
  59         (P)[EI_MAG3] == ELFMAG3)
  60
  61         if (sz > EI_NIDENT && LIBELF_IS_ELF(image)) {
  62                 _libelf_init_elf(e, ELF_K_ELF);
  63                 e->e_class = image[EI_CLASS];
  64                 e->e_byteorder = image[EI_DATA];
  65                 e->e_version = image[EI_VERSION];
  66
  67                 if (e->e_version > EV_CURRENT) {
  68                         e = _libelf_release_elf(e);
  69                         LIBELF_SET_ERROR(VERSION, 0);
  70                         return (NULL);
  71                 }
  72
  73                 if ((e->e_byteorder != ELFDATA2LSB && e->e_byteorder !=
  74                     ELFDATA2MSB) || (e->e_class != ELFCLASS32 && e->e_class !=
  75                     ELFCLASS64)) {
  76                         e = _libelf_release_elf(e);
  77                         LIBELF_SET_ERROR(HEADER, 0);
  78                         return (NULL);
  79                 }
  80
  81         } else if (sz >= SARMAG &&
  82             strncmp(image, ARMAG, (size_t) SARMAG) == 0) {
  83                 _libelf_init_elf(e, ELF_K_AR);
  84                 e = _libelf_ar_open(e);
  85         } else
  86                 _libelf_init_elf(e, ELF_K_NONE);
  87
  88         return (e);
  89 }