-
Notifications
You must be signed in to change notification settings - Fork 24
/
elf32.c
243 lines (214 loc) · 6.87 KB
/
elf32.c
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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
/* $NetBSD: elf32.c,v 1.7 2008/04/28 20:24:16 martin Exp $ */
/*-
* Copyright (c) 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Andrew Doran.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1996 Christopher G. Demetriou
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the
* NetBSD Project. See http://www.NetBSD.org/ for
* information about NetBSD.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
*/
#include <sys/cdefs.h>
#if !defined(lint)
__RCSID("$NetBSD: elf32.c,v 1.7 2008/04/28 20:24:16 martin Exp $");
#endif
#ifndef ELFSIZE
#define ELFSIZE 32
#endif
#include <sys/param.h>
#include <sys/exec_elf.h>
#include <sys/queue.h>
#include <dev/lockstat.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>
#include "extern.h"
#if (ELFSIZE == 32)
#define NAME(x) x##32
#elif (ELFSIZE == 64)
#define NAME(x) x##64
#endif
static int nsyms;
static Elf_Sym *symp;
static char *strp;
int
NAME(loadsym)(int fd)
{
Elf_Shdr symhdr, strhdr;
Elf_Ehdr ehdr;
size_t sz;
off_t off;
int i;
/*
* Read the ELF header and make sure it's OK.
*/
if (pread(fd, &ehdr, sizeof(ehdr), 0) != sizeof(ehdr))
return -1;
if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
ehdr.e_ident[EI_CLASS] != ELFCLASS)
return -1;
switch (ehdr.e_machine) {
ELFDEFNNAME(MACHDEP_ID_CASES)
default:
return -1;
}
/*
* Find the symbol table header, and make sure the binary isn't
* stripped.
*/
off = ehdr.e_shoff;
for (i = 0; i < ehdr.e_shnum; i++, off += sizeof(symhdr)) {
sz = pread(fd, &symhdr, sizeof(symhdr), off);
if (sz != sizeof(symhdr))
err(EXIT_FAILURE, "pread (section headers)");
if (symhdr.sh_type == SHT_SYMTAB)
break;
}
if (i == ehdr.e_shnum || symhdr.sh_offset == 0)
err(EXIT_FAILURE, "namelist is stripped");
/*
* Pull in the string table header, and then read in both the symbol
* table and string table proper.
*
* XXX We can't use mmap(), as /dev/ksyms doesn't support mmap yet.
*/
off = ehdr.e_shoff + symhdr.sh_link * sizeof(symhdr);
if (pread(fd, &strhdr, sizeof(strhdr), off) != sizeof(strhdr))
err(EXIT_FAILURE, "pread");
if ((symp = malloc(symhdr.sh_size)) == NULL)
err(EXIT_FAILURE, "malloc (symbol table)");
sz = pread(fd, symp, symhdr.sh_size, symhdr.sh_offset );
if (sz != symhdr.sh_size)
err(EXIT_FAILURE, "pread (symbol table)");
if ((strp = malloc(strhdr.sh_size)) == NULL)
err(EXIT_FAILURE, "malloc (string table)");
sz = pread(fd, strp, strhdr.sh_size, strhdr.sh_offset);
if (sz != strhdr.sh_size)
err(EXIT_FAILURE, "pread (string table)");
nsyms = (int)(symhdr.sh_size / sizeof(Elf_Sym));
return 0;
}
int
NAME(findsym)(findsym_t find, char *name, uintptr_t *start, uintptr_t *end)
{
static int lastptr[FIND_MAX];
uintptr_t sa, ea;
int i, rv, st, off;
switch (find) {
case LOCK_BYNAME:
case LOCK_BYADDR:
st = STT_OBJECT;
break;
case FUNC_BYNAME:
case FUNC_BYADDR:
st = STT_FUNC;
break;
default:
return -1;
}
rv = -1;
#ifdef dump_core
for (i = lastptr[find];;) {
#else
for (i = 0; i < nsyms; i++) {
#endif
switch (find) {
case LOCK_BYNAME:
case FUNC_BYNAME:
if (ELF_ST_TYPE(symp[i].st_info) != st)
break;
if (strcmp(&strp[symp[i].st_name], name) != 0)
break;
*start = (uintptr_t)symp[i].st_value;
*end = *start + (uintptr_t)symp[i].st_size;
goto found;
case LOCK_BYADDR:
case FUNC_BYADDR:
if (ELF_ST_TYPE(symp[i].st_info) != st)
break;
sa = (uintptr_t)symp[i].st_value;
ea = sa + (uintptr_t)symp[i].st_size - 1;
if (*start < sa || *start > ea)
break;
off = (int)(*start - sa);
*start = sa;
if (end != NULL)
*end = ea;
if (name == NULL)
goto found;
if (off == 0)
strlcpy(name, &strp[symp[i].st_name],
NAME_SIZE);
else
snprintf(name, NAME_SIZE, "%s+%x",
&strp[symp[i].st_name], off);
goto found;
default:
break;
}
#ifdef dump_core
if (++i >= nsyms)
i = 0;
if (i == lastptr[find])
return -1;
#endif
}
return -1;
found:
lastptr[find] = i;
return 0;
}