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 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
41 Elf *
_libelf_memory(unsigned char * image,size_t sz,int reporterror)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