1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
|
/* Copyright (C) 1999, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Jaeger <aj@suse.de>, 1999 and
Jakub Jelinek <jakub@redhat.com>, 1999.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* The code in this file and in readelflib is a heavily simplified
version of the readelf program that's part of the current binutils
development version. Besides the simplification, it has also been
modified to read some other file formats. */
#include <elf.h>
#include <error.h>
#include <link.h>
#include <libintl.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <a.out.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <gnu/lib-names.h>
#include "ldconfig.h"
#define Elf32_CLASS ELFCLASS32
#define Elf64_CLASS ELFCLASS64
struct known_names
{
const char *soname;
int flag;
};
static struct known_names interpreters [] =
{
{"/lib/" LD_SO, FLAG_ELF_LIBC6},
{"/lib/ld-linux.so.1", FLAG_ELF_LIBC5}
};
static struct known_names known_libs [] =
{
/* Old names: */
{"libc.so.5", FLAG_ELF_LIBC5},
{"libm.so.5", FLAG_ELF_LIBC5},
/* Current names: */
{LIBC_SO, FLAG_ELF_LIBC6},
{LIBM_SO, FLAG_ELF_LIBC6}
};
/* Returns 0 if everything is ok, != 0 in case of error. */
int
process_file (const char *file_name, const char *lib, int *flag,
char **soname, int is_link)
{
FILE *file;
struct stat statbuf;
void *file_contents;
int ret;
ElfW(Ehdr) *elf_header;
struct exec *aout_header;
ret = 0;
*flag = FLAG_ANY;
*soname = NULL;
file = fopen (file_name, "rb");
if (file == NULL)
{
/* No error for stale symlink. */
if (is_link && strstr (file_name, ".so.") != NULL)
return 1;
error (0, 0, _("Input file %s not found.\n"), file_name);
return 1;
}
if (fstat (fileno (file), &statbuf) < 0)
{
error (0, 0, _("Cannot fstat file %s.\n"), file_name);
fclose (file);
return 1;
}
/* Check that the file is large enough so that we can access the
information. We're only checking the size of the headers here. */
if (statbuf.st_size < sizeof (struct exec)
|| statbuf.st_size < sizeof (ElfW(Ehdr)))
{
error (0, 0, _("File %s is too small, not checked."), file_name);
fclose (file);
return 1;
}
file_contents = mmap (0, statbuf.st_size, PROT_READ, MAP_SHARED,
fileno (file), 0);
if (file_contents == MAP_FAILED)
{
error (0, 0, _("Cannot mmap file %s.\n"), file_name);
fclose (file);
return 1;
}
/* First check if this is an aout file. */
aout_header = (struct exec *) file_contents;
if (N_MAGIC (*aout_header) == ZMAGIC
|| N_MAGIC (*aout_header) == QMAGIC)
{
/* Aout files don't have a soname, just return the name
including the major number. */
char *copy, *major, *dot;
copy = xstrdup (lib);
major = strstr (copy, ".so.");
if (major)
{
dot = strstr (major + 4, ".");
if (dot)
*dot = '\0';
}
*soname = copy;
*flag = FLAG_LIBC4;
goto done;
}
elf_header = (ElfW(Ehdr) *) file_contents;
if (elf_header->e_ident [EI_MAG0] != ELFMAG0
|| elf_header->e_ident [EI_MAG1] != ELFMAG1
|| elf_header->e_ident [EI_MAG2] != ELFMAG2
|| elf_header->e_ident [EI_MAG3] != ELFMAG3)
{
/* The file is neither ELF nor aout. Check if it's a linker script,
like libc.so - otherwise complain. */
int len = statbuf.st_size;
/* Only search the beginning of the file. */
if (len > 512)
len = 512;
if (memmem (file_contents, len, "GROUP", 5) == NULL
&& memmem (file_contents, len, "GNU ld script", 13) == NULL)
error (0, 0, _("%s is not an ELF file - it has the wrong magic bytes at the start.\n"),
file_name);
ret = 1;
goto done;
}
if (process_elf_file (file_name, lib, flag, soname, file_contents,
statbuf.st_size))
ret = 1;
done:
/* Clean up allocated memory and resources. */
munmap (file_contents, statbuf.st_size);
fclose (file);
return ret;
}
/* Get architecture specific version of process_elf_file. */
#include "readelflib.c"
|