1 /*-
2 * Copyright (c) 2013 FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Pawel Jakub Dawidek under sponsorship from
6 * the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD: releng/10.1/sys/kern/subr_capability.c 258324 2013-11-18 22:37:01Z pjd $");
32
33 /*
34 * Note that this file is compiled into the kernel and into libc.
35 */
36
37 #ifdef _KERNEL
38 #include <sys/types.h>
39 #include <sys/capability.h>
40 #include <sys/systm.h>
41
42 #include <machine/stdarg.h>
43 #else /* !_KERNEL */
44 #include <sys/types.h>
45 #include <sys/capability.h>
46
47 #include <assert.h>
48 #include <stdarg.h>
49 #include <stdbool.h>
50 #include <stdint.h>
51 #include <string.h>
52 #endif
53
54 #ifdef _KERNEL
55 #define assert(exp) KASSERT((exp), ("%s:%u", __func__, __LINE__))
56 #endif
57
58 #define CAPARSIZE_MIN (CAP_RIGHTS_VERSION_00 + 2)
59 #define CAPARSIZE_MAX (CAP_RIGHTS_VERSION + 2)
60
61 static __inline int
62 right_to_index(uint64_t right)
63 {
64 static const int bit2idx[] = {
65 -1, 0, 1, -1, 2, -1, -1, -1, 3, -1, -1, -1, -1, -1, -1, -1,
66 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
67 };
68 int idx;
69
70 idx = CAPIDXBIT(right);
71 assert(idx >= 0 && idx < sizeof(bit2idx) / sizeof(bit2idx[0]));
72 return (bit2idx[idx]);
73 }
74
75 static void
76 cap_rights_vset(cap_rights_t *rights, va_list ap)
77 {
78 uint64_t right;
79 int i, n;
80
81 assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00);
82
83 n = CAPARSIZE(rights);
84 assert(n >= CAPARSIZE_MIN && n <= CAPARSIZE_MAX);
85
86 for (;;) {
87 right = (uint64_t)va_arg(ap, unsigned long long);
88 if (right == 0)
89 break;
90 assert(CAPRVER(right) == 0);
91 i = right_to_index(right);
92 assert(i >= 0);
93 assert(i < n);
94 assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right));
95 rights->cr_rights[i] |= right;
96 assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right));
97 }
98 }
99
100 static void
101 cap_rights_vclear(cap_rights_t *rights, va_list ap)
102 {
103 uint64_t right;
104 int i, n;
105
106 assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00);
107
108 n = CAPARSIZE(rights);
109 assert(n >= CAPARSIZE_MIN && n <= CAPARSIZE_MAX);
110
111 for (;;) {
112 right = (uint64_t)va_arg(ap, unsigned long long);
113 if (right == 0)
114 break;
115 assert(CAPRVER(right) == 0);
116 i = right_to_index(right);
117 assert(i >= 0);
118 assert(i < n);
119 assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right));
120 rights->cr_rights[i] &= ~(right & 0x01FFFFFFFFFFFFFFULL);
121 assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right));
122 }
123 }
124
125 static bool
126 cap_rights_is_vset(const cap_rights_t *rights, va_list ap)
127 {
128 uint64_t right;
129 int i, n;
130
131 assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00);
132
133 n = CAPARSIZE(rights);
134 assert(n >= CAPARSIZE_MIN && n <= CAPARSIZE_MAX);
135
136 for (;;) {
137 right = (uint64_t)va_arg(ap, unsigned long long);
138 if (right == 0)
139 break;
140 assert(CAPRVER(right) == 0);
141 i = right_to_index(right);
142 assert(i >= 0);
143 assert(i < n);
144 assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right));
145 if ((rights->cr_rights[i] & right) != right)
146 return (false);
147 }
148
149 return (true);
150 }
151
152 cap_rights_t *
153 __cap_rights_init(int version, cap_rights_t *rights, ...)
154 {
155 unsigned int n;
156 va_list ap;
157
158 assert(version == CAP_RIGHTS_VERSION_00);
159
160 n = version + 2;
161 assert(n >= CAPARSIZE_MIN && n <= CAPARSIZE_MAX);
162 memset(rights->cr_rights, 0, sizeof(rights->cr_rights[0]) * n);
163 CAP_NONE(rights);
164 va_start(ap, rights);
165 cap_rights_vset(rights, ap);
166 va_end(ap);
167
168 return (rights);
169 }
170
171 cap_rights_t *
172 __cap_rights_set(cap_rights_t *rights, ...)
173 {
174 va_list ap;
175
176 assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00);
177
178 va_start(ap, rights);
179 cap_rights_vset(rights, ap);
180 va_end(ap);
181
182 return (rights);
183 }
184
185 cap_rights_t *
186 __cap_rights_clear(cap_rights_t *rights, ...)
187 {
188 va_list ap;
189
190 assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00);
191
192 va_start(ap, rights);
193 cap_rights_vclear(rights, ap);
194 va_end(ap);
195
196 return (rights);
197 }
198
199 bool
200 __cap_rights_is_set(const cap_rights_t *rights, ...)
201 {
202 va_list ap;
203 bool ret;
204
205 assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00);
206
207 va_start(ap, rights);
208 ret = cap_rights_is_vset(rights, ap);
209 va_end(ap);
210
211 return (ret);
212 }
213
214 bool
215 cap_rights_is_valid(const cap_rights_t *rights)
216 {
217 cap_rights_t allrights;
218 int i, j;
219
220 if (CAPVER(rights) != CAP_RIGHTS_VERSION_00)
221 return (false);
222 if (CAPARSIZE(rights) < CAPARSIZE_MIN ||
223 CAPARSIZE(rights) > CAPARSIZE_MAX) {
224 return (false);
225 }
226 CAP_ALL(&allrights);
227 if (!cap_rights_contains(&allrights, rights))
228 return (false);
229 for (i = 0; i < CAPARSIZE(rights); i++) {
230 j = right_to_index(rights->cr_rights[i]);
231 if (i != j)
232 return (false);
233 if (i > 0) {
234 if (CAPRVER(rights->cr_rights[i]) != 0)
235 return (false);
236 }
237 }
238
239 return (true);
240 }
241
242 cap_rights_t *
243 cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src)
244 {
245 unsigned int i, n;
246
247 assert(CAPVER(dst) == CAP_RIGHTS_VERSION_00);
248 assert(CAPVER(src) == CAP_RIGHTS_VERSION_00);
249 assert(CAPVER(dst) == CAPVER(src));
250 assert(cap_rights_is_valid(src));
251 assert(cap_rights_is_valid(dst));
252
253 n = CAPARSIZE(dst);
254 assert(n >= CAPARSIZE_MIN && n <= CAPARSIZE_MAX);
255
256 for (i = 0; i < n; i++)
257 dst->cr_rights[i] |= src->cr_rights[i];
258
259 assert(cap_rights_is_valid(src));
260 assert(cap_rights_is_valid(dst));
261
262 return (dst);
263 }
264
265 cap_rights_t *
266 cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src)
267 {
268 unsigned int i, n;
269
270 assert(CAPVER(dst) == CAP_RIGHTS_VERSION_00);
271 assert(CAPVER(src) == CAP_RIGHTS_VERSION_00);
272 assert(CAPVER(dst) == CAPVER(src));
273 assert(cap_rights_is_valid(src));
274 assert(cap_rights_is_valid(dst));
275
276 n = CAPARSIZE(dst);
277 assert(n >= CAPARSIZE_MIN && n <= CAPARSIZE_MAX);
278
279 for (i = 0; i < n; i++) {
280 dst->cr_rights[i] &=
281 ~(src->cr_rights[i] & 0x01FFFFFFFFFFFFFFULL);
282 }
283
284 assert(cap_rights_is_valid(src));
285 assert(cap_rights_is_valid(dst));
286
287 return (dst);
288 }
289
290 bool
291 cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little)
292 {
293 unsigned int i, n;
294
295 assert(CAPVER(big) == CAP_RIGHTS_VERSION_00);
296 assert(CAPVER(little) == CAP_RIGHTS_VERSION_00);
297 assert(CAPVER(big) == CAPVER(little));
298
299 n = CAPARSIZE(big);
300 assert(n >= CAPARSIZE_MIN && n <= CAPARSIZE_MAX);
301
302 for (i = 0; i < n; i++) {
303 if ((big->cr_rights[i] & little->cr_rights[i]) !=
304 little->cr_rights[i]) {
305 return (false);
306 }
307 }
308
309 return (true);
310 }
Cache object: 1f1d931a451d51503924b0684f581397
|