1 /* $NetBSD: libelf_memory.c,v 1.5 2024/03/03 17:37:34 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2011 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 <ar.h>
36 #include <assert.h>
37 #include <string.h>
38 #include <libelf.h>
39
40 #include "_libelf.h"
41
42 __RCSID("$NetBSD: libelf_memory.c,v 1.5 2024/03/03 17:37:34 christos Exp $");
43 ELFTC_VCSID("Id: libelf_memory.c 3977 2022-05-01 06:45:34Z jkoshy");
44
45 /*
46 * Create an ELF descriptor for a memory image, optionally reporting
47 * parse errors.
48 */
49
50 Elf *
_libelf_memory(unsigned char * image,size_t sz,int reporterror)51 _libelf_memory(unsigned char *image, size_t sz, int reporterror)
52 {
53 Elf *e;
54 int e_class;
55 enum Elf_Error error;
56 unsigned int e_byteorder, e_version;
57
58 assert(image != NULL);
59 assert(sz > 0);
60
61 if ((e = _libelf_allocate_elf()) == NULL)
62 return (NULL);
63
64 e->e_cmd = ELF_C_READ;
65 e->e_rawfile = image;
66 e->e_rawsize = (off_t) sz;
67
68 #undef LIBELF_IS_ELF
69 #define LIBELF_IS_ELF(P) ((P)[EI_MAG0] == ELFMAG0 && \
70 (P)[EI_MAG1] == ELFMAG1 && (P)[EI_MAG2] == ELFMAG2 && \
71 (P)[EI_MAG3] == ELFMAG3)
72
73 if (sz > EI_NIDENT && LIBELF_IS_ELF(image)) {
74 e_byteorder = image[EI_DATA];
75 e_class = image[EI_CLASS];
76 e_version = image[EI_VERSION];
77
78 error = ELF_E_NONE;
79
80 if (e_version > EV_CURRENT)
81 error = ELF_E_VERSION;
82 else if ((e_byteorder != ELFDATA2LSB && e_byteorder !=
83 ELFDATA2MSB) || (e_class != ELFCLASS32 && e_class !=
84 ELFCLASS64))
85 error = ELF_E_HEADER;
86
87 if (error != ELF_E_NONE) {
88 if (reporterror) {
89 LIBELF_PRIVATE(error) = LIBELF_ERROR(error, 0);
90 _libelf_release_elf(e);
91 return (NULL);
92 }
93 } else {
94 _libelf_init_elf(e, ELF_K_ELF);
95
96 e->e_byteorder = e_byteorder;
97 e->e_class = e_class;
98 e->e_version = e_version;
99 }
100 } else if (sz >= SARMAG &&
101 strncmp((const char *) image, ARMAG, (size_t) SARMAG) == 0)
102 return (_libelf_ar_open(e, reporterror));
103
104 return (e);
105 }
106