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
34ELFTC_VCSID("$Id: libelf_memory.c 3738 2019-05-05 21:49:06Z jkoshy $");
35
36/*
37 * Create an ELF descriptor for a memory image, optionally reporting
38 * parse errors.
39 */
40
41Elf *
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 = (off_t) 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				_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}
97