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
|
/* $OpenBSD: sod.c,v 1.1 2006/05/03 16:10:52 drahn Exp $ */
/*
* Copyright (c) 1993 Paul Kranenburg
* 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 by Paul Kranenburg.
* 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.
*
*/
#include <sys/types.h>
#include <sys/syslimits.h>
#include <stdio.h>
#include <fcntl.h>
#include <nlist.h>
#include <link.h>
#include <limits.h>
#include <machine/exec.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#if 0
#include "syscall.h"
#include "archdep.h"
#include "util.h"
#endif
#include "sod.h"
int _dl_hinthash(char *cp, int vmajor, int vminor);
void _dl_maphints(void);
/*
* Populate sod struct for dlopen's call to map_object
*/
void
_dl_build_sod(const char *name, struct sod *sodp)
{
unsigned int tuplet;
int major, minor;
char *realname, *tok, *etok, *cp;
/* default is an absolute or relative path */
sodp->sod_name = (long)strdup(name); /* strtok is destructive */
sodp->sod_library = 0;
sodp->sod_major = sodp->sod_minor = 0;
/* does it look like /^lib/ ? */
if (strncmp((char *)sodp->sod_name, "lib", 3) != 0)
goto backout;
/* is this a filename? */
if (strchr((char *)sodp->sod_name, '/'))
goto backout;
/* skip over 'lib' */
cp = (char *)sodp->sod_name + 3;
realname = cp;
/* dot guardian */
if ((strchr(cp, '.') == NULL) || (*(cp+strlen(cp)-1) == '.'))
goto backout;
cp = strstr(cp, ".so");
if (cp == NULL)
goto backout;
/* default */
major = minor = -1;
/* loop through name - parse skipping name */
for (tuplet = 0; (tok = strsep(&cp, ".")) != NULL; tuplet++) {
switch (tuplet) {
case 0:
/* empty tok, we already skipped to "\.so.*" */
break;
case 1:
/* 'so' extension */
break;
case 2:
/* major version extension */
major = strtol(tok, &etok, 10);
if (*tok == '\0' || *etok != '\0')
goto backout;
break;
case 3:
/* minor version extension */
minor = strtol(tok, &etok, 10);
if (*tok == '\0' || *etok != '\0')
goto backout;
break;
/* if we get here, it must be weird */
default:
goto backout;
}
}
if (realname == NULL)
goto backout;
cp = (char *)sodp->sod_name;
sodp->sod_name = (long)strdup(realname);
free(cp);
sodp->sod_library = 1;
sodp->sod_major = major;
sodp->sod_minor = minor;
return;
backout:
free((char *)sodp->sod_name);
sodp->sod_name = (long)strdup(name);
}
static struct hints_header *hheader = NULL;
static struct hints_bucket *hbuckets;
static char *hstrtab;
char *_dl_hint_search_path = NULL;
#define HINTS_VALID (hheader != NULL && hheader != (struct hints_header *)-1)
void
_dl_maphints(void)
{
struct stat sb;
caddr_t addr = MAP_FAILED;
long hsize = 0;
int hfd;
if ((hfd = open(_PATH_LD_HINTS, O_RDONLY)) < 0)
goto bad_hints;
if (fstat(hfd, &sb) != 0 || !S_ISREG(sb.st_mode) ||
sb.st_size < sizeof(struct hints_header) || sb.st_size > LONG_MAX)
goto bad_hints;
hsize = (long)sb.st_size;
addr = (void *)mmap(0, hsize, PROT_READ, MAP_PRIVATE, hfd, 0);
if (addr == MAP_FAILED)
goto bad_hints;
hheader = (struct hints_header *)addr;
if (HH_BADMAG(*hheader) || hheader->hh_ehints > hsize)
goto bad_hints;
if (hheader->hh_version != LD_HINTS_VERSION_1 &&
hheader->hh_version != LD_HINTS_VERSION_2)
goto bad_hints;
hbuckets = (struct hints_bucket *)(addr + hheader->hh_hashtab);
hstrtab = (char *)(addr + hheader->hh_strtab);
if (hheader->hh_version >= LD_HINTS_VERSION_2)
_dl_hint_search_path = hstrtab + hheader->hh_dirlist;
/* close the file descriptor, leaving the hints mapped */
close(hfd);
return;
bad_hints:
if (addr != MAP_FAILED)
munmap(addr, hsize);
if (hfd != -1)
close(hfd);
hheader = (struct hints_header *)-1;
}
char *
_dl_findhint(char *name, int major, int minor, char *preferred_path)
{
struct hints_bucket *bp;
/*
* If not mapped, and we have not tried before, try to map the
* hints, if previous attempts failed hheader is -1 and we
* do not wish to retry it.
*/
if (hheader == NULL)
_dl_maphints();
/* if it failed to map, return failure */
if (!(HINTS_VALID))
return NULL;
bp = hbuckets + (_dl_hinthash(name, major, minor) % hheader->hh_nbucket);
while (1) {
/* Sanity check */
if (bp->hi_namex >= hheader->hh_strtab_sz) {
printf("Bad name index: %#x\n", bp->hi_namex);
exit(7);
break;
}
if (bp->hi_pathx >= hheader->hh_strtab_sz) {
printf("Bad path index: %#x\n", bp->hi_pathx);
exit(7);
break;
}
if (strcmp(name, hstrtab + bp->hi_namex) == 0) {
/* It's `name', check version numbers */
if (bp->hi_major == major &&
(bp->hi_ndewey < 2 || bp->hi_minor >= minor)) {
if (preferred_path == NULL) {
return hstrtab + bp->hi_pathx;
} else {
char *path = hstrtab + bp->hi_pathx;
char *edir = strrchr(path, '/');
if ((strncmp(preferred_path, path,
(edir - path)) == 0) &&
(preferred_path[edir - path] == '\0'))
return path;
}
}
}
if (bp->hi_next == -1)
break;
/* Move on to next in bucket */
bp = &hbuckets[bp->hi_next];
}
/* No hints available for name */
return NULL;
}
int
_dl_hinthash(char *cp, int vmajor, int vminor)
{
int k = 0;
while (*cp)
k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff;
k = (((k << 1) + (k >> 14)) ^ (vmajor*257)) & 0x3fff;
if (hheader->hh_version == LD_HINTS_VERSION_1)
k = (((k << 1) + (k >> 14)) ^ (vminor*167)) & 0x3fff;
return k;
}
|
