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
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
|
/* $NetBSD: symver.c,v 1.4 2013/05/09 15:38:14 christos Exp $ */
/*-
* Copyright 1996, 1997, 1998, 1999, 2000 John D. Polstra.
* Copyright 2003 Alexander Kabaev <kan@FreeBSD.ORG>.
* Copyright 2009, 2010, 2011 Konstantin Belousov <kib@FreeBSD.ORG>.
* 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.
*
* 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.
*
* $FreeBSD: head/libexec/rtld-elf/rtld.c 220004 2011-03-25 18:23:10Z avg $
*/
/*-
* Copyright (c) 2011 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by NONAKA Kimihiro.
*
* 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.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: symver.c,v 1.4 2013/05/09 15:38:14 christos Exp $");
#include <sys/param.h>
#include <sys/exec_elf.h>
#include <string.h>
#include "debug.h"
#include "rtld.h"
void
_rtld_object_add_name(Obj_Entry *obj, const char *name)
{
Name_Entry *entry;
size_t len;
len = strlen(name);
entry = xmalloc(sizeof(Name_Entry) + len);
if (entry != NULL) {
strcpy(entry->name, name);
SIMPLEQ_INSERT_TAIL(&obj->names, entry, link);
}
}
int
_rtld_object_match_name(const Obj_Entry *obj, const char *name)
{
Name_Entry *entry;
SIMPLEQ_FOREACH(entry, &obj->names, link) {
dbg(("name: %s, entry->name: %s", name, entry->name));
if (strcmp(name, entry->name) == 0)
return 1;
}
return 0;
}
#ifdef RTLD_LOADER
static Obj_Entry *
locate_dependency(const Obj_Entry *obj, const char *name)
{
const Objlist_Entry *entry;
const Needed_Entry *needed;
SIMPLEQ_FOREACH(entry, &_rtld_list_main, link) {
if (_rtld_object_match_name(entry->obj, name))
return entry->obj;
}
for (needed = obj->needed; needed != NULL; needed = needed->next) {
dbg(("needed: name: %s, str: %s", name,
&obj->strtab[needed->name]));
if (strcmp(name, &obj->strtab[needed->name]) == 0 ||
(needed->obj != NULL && _rtld_object_match_name(needed->obj, name))) {
/*
* If there is DT_NEEDED for the name we are looking
* for, we are all set. Note that object might not be
* found if dependency was not loaded yet, so the
* function can return NULL here. This is expected
* and handled properly by the caller.
*/
return needed->obj;
}
}
_rtld_error("%s: Unexpected inconsistency: dependency %s not found",
obj->path, name);
return NULL;
}
static int
check_object_provided_version(Obj_Entry *refobj, const Obj_Entry *depobj,
const Elf_Vernaux *vna)
{
const char *vername = &refobj->strtab[vna->vna_name];
const char *depstrtab = depobj->strtab;
const Elf_Verdef *vd = depobj->verdef;
const Elf_Word hash = vna->vna_hash;
if (vd == NULL) {
_rtld_error("%s: version %s required by %s not defined",
depobj->path, vername, refobj->path);
return -1;
}
for (;; vd = (const Elf_Verdef *)((const char *)vd + vd->vd_next)) {
if (vd->vd_version != VER_DEF_CURRENT) {
_rtld_error(
"%s: Unsupported version %d of Elf_Verdef entry",
depobj->path, vd->vd_version);
return -1;
}
dbg(("hash: 0x%x, vd_hash: 0x%x", hash, vd->vd_hash));
if (hash == vd->vd_hash) {
const Elf_Verdaux *vda = (const Elf_Verdaux *)
((const char *)vd + vd->vd_aux);
dbg(("vername: %s, str: %s", vername,
&depstrtab[vda->vda_name]));
if (strcmp(vername, &depstrtab[vda->vda_name]) == 0)
return 0;
}
if (vd->vd_next == 0)
break;
}
if (vna->vna_flags & VER_FLG_WEAK)
return 0;
_rtld_error("%s: version %s required by %s not found", depobj->path,
vername, refobj->path);
return -1;
}
int
_rtld_verify_object_versions(Obj_Entry *obj)
{
const char *strtab = obj->strtab;
const Elf_Verneed *vn;
const Elf_Vernaux *vna;
const Elf_Verdef *vd;
const Elf_Verdaux *vda;
const Obj_Entry *depobj;
int maxvertab, vernum;
dbg(("obj->path: %s", obj->path));
/*
* If we don't have string table or objects that have their version
* requirements already checked, we must be ok.
*/
if (strtab == NULL || obj->vertab != NULL)
return 0;
maxvertab = 0;
/*
* Walk over defined and required version records and figure out
* max index used by any of them. Do very basic sanity checking
* while there.
*/
for (vn = obj->verneed;
vn != NULL;
vn = (const Elf_Verneed *)((const char *)vn + vn->vn_next)) {
if (vn->vn_version != VER_NEED_CURRENT) {
_rtld_error(
"%s: Unsupported version %d of Elf_Verneed entry",
obj->path, vn->vn_version);
return -1;
}
dbg(("verneed: vn_file: %d, str: %s",
vn->vn_file, &strtab[vn->vn_file]));
depobj = locate_dependency(obj, &strtab[vn->vn_file]);
assert(depobj != NULL);
for (vna = (const Elf_Vernaux *)((const char *)vn + vn->vn_aux);
/*CONSTCOND*/1;
vna = (const Elf_Vernaux *)((const char *)vna + vna->vna_next)) {
if (check_object_provided_version(obj, depobj, vna) == -1)
return -1;
vernum = VER_NEED_IDX(vna->vna_other);
if (vernum > maxvertab)
maxvertab = vernum;
if (vna->vna_next == 0) {
/* No more symbols. */
break;
}
}
if (vn->vn_next == 0) {
/* No more dependencies. */
break;
}
}
for (vd = obj->verdef;
vd != NULL;
vd = (const Elf_Verdef *)((const char *)vd + vd->vd_next)) {
if (vd->vd_version != VER_DEF_CURRENT) {
_rtld_error(
"%s: Unsupported version %d of Elf_Verdef entry",
obj->path, vd->vd_version);
return -1;
}
dbg(("verdef: vn_ndx: 0x%x", vd->vd_ndx));
vernum = VER_DEF_IDX(vd->vd_ndx);
if (vernum > maxvertab)
maxvertab = vernum;
if (vd->vd_next == 0) {
/* No more definitions. */
break;
}
}
dbg(("maxvertab: %d", maxvertab));
if (maxvertab == 0)
return 0;
/*
* Store version information in array indexable by version index.
* Verify that object version requirements are satisfied along the
* way.
*/
obj->vertabnum = maxvertab + 1;
obj->vertab = (Ver_Entry *)xcalloc(obj->vertabnum * sizeof(Ver_Entry));
for (vn = obj->verneed;
vn != NULL;
vn = (const Elf_Verneed *)((const char *)vn + vn->vn_next)) {
for (vna = (const Elf_Vernaux *)((const char *)vn + vn->vn_aux);
/*CONSTCOND*/1;
vna = (const Elf_Vernaux *)((const char *)vna + vna->vna_next)) {
vernum = VER_NEED_IDX(vna->vna_other);
assert(vernum <= maxvertab);
obj->vertab[vernum].hash = vna->vna_hash;
obj->vertab[vernum].name = &strtab[vna->vna_name];
obj->vertab[vernum].file = &strtab[vn->vn_file];
obj->vertab[vernum].flags =
(vna->vna_other & VER_NEED_HIDDEN)
? VER_INFO_HIDDEN : 0;
dbg(("verneed: vernum: %d, hash: 0x%x, name: %s, "
"file: %s, flags: 0x%x", vernum,
obj->vertab[vernum].hash, obj->vertab[vernum].name,
obj->vertab[vernum].file,
obj->vertab[vernum].flags));
if (vna->vna_next == 0) {
/* No more symbols. */
break;
}
}
if (vn->vn_next == 0) {
/* No more dependencies. */
break;
}
}
for (vd = obj->verdef;
vd != NULL;
vd = (const Elf_Verdef *)((const char *)vd + vd->vd_next)) {
if ((vd->vd_flags & VER_FLG_BASE) == 0) {
vernum = VER_DEF_IDX(vd->vd_ndx);
assert(vernum <= maxvertab);
vda = (const Elf_Verdaux *)
((const char *)vd + vd->vd_aux);
obj->vertab[vernum].hash = vd->vd_hash;
obj->vertab[vernum].name = &strtab[vda->vda_name];
obj->vertab[vernum].file = NULL;
obj->vertab[vernum].flags = 0;
dbg(("verdef: vernum: %d, hash: 0x%x, name: %s",
vernum, obj->vertab[vernum].hash,
obj->vertab[vernum].name));
}
if (vd->vd_next == 0) {
/* No more definitions. */
break;
}
}
return 0;
}
#endif
|
