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1/*
2 * Implementation of the extensible bitmap type.
3 *
4 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
5 */
6/*
7 * Updated: Hewlett-Packard <paul@paul-moore.com>
8 *
9 * Added support to import/export the NetLabel category bitmap
10 *
11 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
12 */
13/*
14 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
15 * Applied standard bit operations to improve bitmap scanning.
16 */
17
18#include <linux/kernel.h>
19#include <linux/slab.h>
20#include <linux/errno.h>
21#include <net/netlabel.h>
22#include "ebitmap.h"
23#include "policydb.h"
24
25#define BITS_PER_U64 (sizeof(u64) * 8)
26
27int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2)
28{
29 struct ebitmap_node *n1, *n2;
30
31 if (e1->highbit != e2->highbit)
32 return 0;
33
34 n1 = e1->node;
35 n2 = e2->node;
36 while (n1 && n2 &&
37 (n1->startbit == n2->startbit) &&
38 !memcmp(n1->maps, n2->maps, EBITMAP_SIZE / 8)) {
39 n1 = n1->next;
40 n2 = n2->next;
41 }
42
43 if (n1 || n2)
44 return 0;
45
46 return 1;
47}
48
49int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src)
50{
51 struct ebitmap_node *n, *new, *prev;
52
53 ebitmap_init(dst);
54 n = src->node;
55 prev = NULL;
56 while (n) {
57 new = kzalloc(sizeof(*new), GFP_ATOMIC);
58 if (!new) {
59 ebitmap_destroy(dst);
60 return -ENOMEM;
61 }
62 new->startbit = n->startbit;
63 memcpy(new->maps, n->maps, EBITMAP_SIZE / 8);
64 new->next = NULL;
65 if (prev)
66 prev->next = new;
67 else
68 dst->node = new;
69 prev = new;
70 n = n->next;
71 }
72
73 dst->highbit = src->highbit;
74 return 0;
75}
76
77#ifdef CONFIG_NETLABEL
78/**
79 * ebitmap_netlbl_export - Export an ebitmap into a NetLabel category bitmap
80 * @ebmap: the ebitmap to export
81 * @catmap: the NetLabel category bitmap
82 *
83 * Description:
84 * Export a SELinux extensibile bitmap into a NetLabel category bitmap.
85 * Returns zero on success, negative values on error.
86 *
87 */
88int ebitmap_netlbl_export(struct ebitmap *ebmap,
89 struct netlbl_lsm_catmap **catmap)
90{
91 struct ebitmap_node *e_iter = ebmap->node;
92 unsigned long e_map;
93 u32 offset;
94 unsigned int iter;
95 int rc;
96
97 if (e_iter == NULL) {
98 *catmap = NULL;
99 return 0;
100 }
101
102 if (*catmap != NULL)
103 netlbl_catmap_free(*catmap);
104 *catmap = NULL;
105
106 while (e_iter) {
107 offset = e_iter->startbit;
108 for (iter = 0; iter < EBITMAP_UNIT_NUMS; iter++) {
109 e_map = e_iter->maps[iter];
110 if (e_map != 0) {
111 rc = netlbl_catmap_setlong(catmap,
112 offset,
113 e_map,
114 GFP_ATOMIC);
115 if (rc != 0)
116 goto netlbl_export_failure;
117 }
118 offset += EBITMAP_UNIT_SIZE;
119 }
120 e_iter = e_iter->next;
121 }
122
123 return 0;
124
125netlbl_export_failure:
126 netlbl_catmap_free(*catmap);
127 return -ENOMEM;
128}
129
130/**
131 * ebitmap_netlbl_import - Import a NetLabel category bitmap into an ebitmap
132 * @ebmap: the ebitmap to import
133 * @catmap: the NetLabel category bitmap
134 *
135 * Description:
136 * Import a NetLabel category bitmap into a SELinux extensibile bitmap.
137 * Returns zero on success, negative values on error.
138 *
139 */
140int ebitmap_netlbl_import(struct ebitmap *ebmap,
141 struct netlbl_lsm_catmap *catmap)
142{
143 int rc;
144 struct ebitmap_node *e_iter = NULL;
145 struct ebitmap_node *e_prev = NULL;
146 u32 offset = 0, idx;
147 unsigned long bitmap;
148
149 for (;;) {
150 rc = netlbl_catmap_getlong(catmap, &offset, &bitmap);
151 if (rc < 0)
152 goto netlbl_import_failure;
153 if (offset == (u32)-1)
154 return 0;
155
156 /* don't waste ebitmap space if the netlabel bitmap is empty */
157 if (bitmap == 0) {
158 offset += EBITMAP_UNIT_SIZE;
159 continue;
160 }
161
162 if (e_iter == NULL ||
163 offset >= e_iter->startbit + EBITMAP_SIZE) {
164 e_prev = e_iter;
165 e_iter = kzalloc(sizeof(*e_iter), GFP_ATOMIC);
166 if (e_iter == NULL)
167 goto netlbl_import_failure;
168 e_iter->startbit = offset & ~(EBITMAP_SIZE - 1);
169 if (e_prev == NULL)
170 ebmap->node = e_iter;
171 else
172 e_prev->next = e_iter;
173 ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;
174 }
175
176 /* offset will always be aligned to an unsigned long */
177 idx = EBITMAP_NODE_INDEX(e_iter, offset);
178 e_iter->maps[idx] = bitmap;
179
180 /* next */
181 offset += EBITMAP_UNIT_SIZE;
182 }
183
184 /* NOTE: we should never reach this return */
185 return 0;
186
187netlbl_import_failure:
188 ebitmap_destroy(ebmap);
189 return -ENOMEM;
190}
191#endif /* CONFIG_NETLABEL */
192
193/*
194 * Check to see if all the bits set in e2 are also set in e1. Optionally,
195 * if last_e2bit is non-zero, the highest set bit in e2 cannot exceed
196 * last_e2bit.
197 */
198int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2, u32 last_e2bit)
199{
200 struct ebitmap_node *n1, *n2;
201 int i;
202
203 if (e1->highbit < e2->highbit)
204 return 0;
205
206 n1 = e1->node;
207 n2 = e2->node;
208
209 while (n1 && n2 && (n1->startbit <= n2->startbit)) {
210 if (n1->startbit < n2->startbit) {
211 n1 = n1->next;
212 continue;
213 }
214 for (i = EBITMAP_UNIT_NUMS - 1; (i >= 0) && !n2->maps[i]; )
215 i--; /* Skip trailing NULL map entries */
216 if (last_e2bit && (i >= 0)) {
217 u32 lastsetbit = n2->startbit + i * EBITMAP_UNIT_SIZE +
218 __fls(n2->maps[i]);
219 if (lastsetbit > last_e2bit)
220 return 0;
221 }
222
223 while (i >= 0) {
224 if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])
225 return 0;
226 i--;
227 }
228
229 n1 = n1->next;
230 n2 = n2->next;
231 }
232
233 if (n2)
234 return 0;
235
236 return 1;
237}
238
239int ebitmap_get_bit(struct ebitmap *e, unsigned long bit)
240{
241 struct ebitmap_node *n;
242
243 if (e->highbit < bit)
244 return 0;
245
246 n = e->node;
247 while (n && (n->startbit <= bit)) {
248 if ((n->startbit + EBITMAP_SIZE) > bit)
249 return ebitmap_node_get_bit(n, bit);
250 n = n->next;
251 }
252
253 return 0;
254}
255
256int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value)
257{
258 struct ebitmap_node *n, *prev, *new;
259
260 prev = NULL;
261 n = e->node;
262 while (n && n->startbit <= bit) {
263 if ((n->startbit + EBITMAP_SIZE) > bit) {
264 if (value) {
265 ebitmap_node_set_bit(n, bit);
266 } else {
267 unsigned int s;
268
269 ebitmap_node_clr_bit(n, bit);
270
271 s = find_first_bit(n->maps, EBITMAP_SIZE);
272 if (s < EBITMAP_SIZE)
273 return 0;
274
275 /* drop this node from the bitmap */
276 if (!n->next) {
277 /*
278 * this was the highest map
279 * within the bitmap
280 */
281 if (prev)
282 e->highbit = prev->startbit
283 + EBITMAP_SIZE;
284 else
285 e->highbit = 0;
286 }
287 if (prev)
288 prev->next = n->next;
289 else
290 e->node = n->next;
291 kfree(n);
292 }
293 return 0;
294 }
295 prev = n;
296 n = n->next;
297 }
298
299 if (!value)
300 return 0;
301
302 new = kzalloc(sizeof(*new), GFP_ATOMIC);
303 if (!new)
304 return -ENOMEM;
305
306 new->startbit = bit - (bit % EBITMAP_SIZE);
307 ebitmap_node_set_bit(new, bit);
308
309 if (!n)
310 /* this node will be the highest map within the bitmap */
311 e->highbit = new->startbit + EBITMAP_SIZE;
312
313 if (prev) {
314 new->next = prev->next;
315 prev->next = new;
316 } else {
317 new->next = e->node;
318 e->node = new;
319 }
320
321 return 0;
322}
323
324void ebitmap_destroy(struct ebitmap *e)
325{
326 struct ebitmap_node *n, *temp;
327
328 if (!e)
329 return;
330
331 n = e->node;
332 while (n) {
333 temp = n;
334 n = n->next;
335 kfree(temp);
336 }
337
338 e->highbit = 0;
339 e->node = NULL;
340 return;
341}
342
343int ebitmap_read(struct ebitmap *e, void *fp)
344{
345 struct ebitmap_node *n = NULL;
346 u32 mapunit, count, startbit, index;
347 u64 map;
348 __le32 buf[3];
349 int rc, i;
350
351 ebitmap_init(e);
352
353 rc = next_entry(buf, fp, sizeof buf);
354 if (rc < 0)
355 goto out;
356
357 mapunit = le32_to_cpu(buf[0]);
358 e->highbit = le32_to_cpu(buf[1]);
359 count = le32_to_cpu(buf[2]);
360
361 if (mapunit != BITS_PER_U64) {
362 printk(KERN_ERR "SELinux: ebitmap: map size %u does not "
363 "match my size %Zd (high bit was %d)\n",
364 mapunit, BITS_PER_U64, e->highbit);
365 goto bad;
366 }
367
368 /* round up e->highbit */
369 e->highbit += EBITMAP_SIZE - 1;
370 e->highbit -= (e->highbit % EBITMAP_SIZE);
371
372 if (!e->highbit) {
373 e->node = NULL;
374 goto ok;
375 }
376
377 for (i = 0; i < count; i++) {
378 rc = next_entry(&startbit, fp, sizeof(u32));
379 if (rc < 0) {
380 printk(KERN_ERR "SELinux: ebitmap: truncated map\n");
381 goto bad;
382 }
383 startbit = le32_to_cpu(startbit);
384
385 if (startbit & (mapunit - 1)) {
386 printk(KERN_ERR "SELinux: ebitmap start bit (%d) is "
387 "not a multiple of the map unit size (%u)\n",
388 startbit, mapunit);
389 goto bad;
390 }
391 if (startbit > e->highbit - mapunit) {
392 printk(KERN_ERR "SELinux: ebitmap start bit (%d) is "
393 "beyond the end of the bitmap (%u)\n",
394 startbit, (e->highbit - mapunit));
395 goto bad;
396 }
397
398 if (!n || startbit >= n->startbit + EBITMAP_SIZE) {
399 struct ebitmap_node *tmp;
400 tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
401 if (!tmp) {
402 printk(KERN_ERR
403 "SELinux: ebitmap: out of memory\n");
404 rc = -ENOMEM;
405 goto bad;
406 }
407 /* round down */
408 tmp->startbit = startbit - (startbit % EBITMAP_SIZE);
409 if (n)
410 n->next = tmp;
411 else
412 e->node = tmp;
413 n = tmp;
414 } else if (startbit <= n->startbit) {
415 printk(KERN_ERR "SELinux: ebitmap: start bit %d"
416 " comes after start bit %d\n",
417 startbit, n->startbit);
418 goto bad;
419 }
420
421 rc = next_entry(&map, fp, sizeof(u64));
422 if (rc < 0) {
423 printk(KERN_ERR "SELinux: ebitmap: truncated map\n");
424 goto bad;
425 }
426 map = le64_to_cpu(map);
427
428 index = (startbit - n->startbit) / EBITMAP_UNIT_SIZE;
429 while (map) {
430 n->maps[index++] = map & (-1UL);
431 map = EBITMAP_SHIFT_UNIT_SIZE(map);
432 }
433 }
434ok:
435 rc = 0;
436out:
437 return rc;
438bad:
439 if (!rc)
440 rc = -EINVAL;
441 ebitmap_destroy(e);
442 goto out;
443}
444
445int ebitmap_write(struct ebitmap *e, void *fp)
446{
447 struct ebitmap_node *n;
448 u32 count;
449 __le32 buf[3];
450 u64 map;
451 int bit, last_bit, last_startbit, rc;
452
453 buf[0] = cpu_to_le32(BITS_PER_U64);
454
455 count = 0;
456 last_bit = 0;
457 last_startbit = -1;
458 ebitmap_for_each_positive_bit(e, n, bit) {
459 if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) {
460 count++;
461 last_startbit = rounddown(bit, BITS_PER_U64);
462 }
463 last_bit = roundup(bit + 1, BITS_PER_U64);
464 }
465 buf[1] = cpu_to_le32(last_bit);
466 buf[2] = cpu_to_le32(count);
467
468 rc = put_entry(buf, sizeof(u32), 3, fp);
469 if (rc)
470 return rc;
471
472 map = 0;
473 last_startbit = INT_MIN;
474 ebitmap_for_each_positive_bit(e, n, bit) {
475 if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) {
476 __le64 buf64[1];
477
478 /* this is the very first bit */
479 if (!map) {
480 last_startbit = rounddown(bit, BITS_PER_U64);
481 map = (u64)1 << (bit - last_startbit);
482 continue;
483 }
484
485 /* write the last node */
486 buf[0] = cpu_to_le32(last_startbit);
487 rc = put_entry(buf, sizeof(u32), 1, fp);
488 if (rc)
489 return rc;
490
491 buf64[0] = cpu_to_le64(map);
492 rc = put_entry(buf64, sizeof(u64), 1, fp);
493 if (rc)
494 return rc;
495
496 /* set up for the next node */
497 map = 0;
498 last_startbit = rounddown(bit, BITS_PER_U64);
499 }
500 map |= (u64)1 << (bit - last_startbit);
501 }
502 /* write the last node */
503 if (map) {
504 __le64 buf64[1];
505
506 /* write the last node */
507 buf[0] = cpu_to_le32(last_startbit);
508 rc = put_entry(buf, sizeof(u32), 1, fp);
509 if (rc)
510 return rc;
511
512 buf64[0] = cpu_to_le64(map);
513 rc = put_entry(buf64, sizeof(u64), 1, fp);
514 if (rc)
515 return rc;
516 }
517 return 0;
518}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Implementation of the extensible bitmap type.
4 *
5 * Author : Stephen Smalley, <sds@tycho.nsa.gov>
6 */
7/*
8 * Updated: Hewlett-Packard <paul@paul-moore.com>
9 *
10 * Added support to import/export the NetLabel category bitmap
11 *
12 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
13 */
14/*
15 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
16 * Applied standard bit operations to improve bitmap scanning.
17 */
18
19#include <linux/kernel.h>
20#include <linux/slab.h>
21#include <linux/errno.h>
22#include <net/netlabel.h>
23#include "ebitmap.h"
24#include "policydb.h"
25
26#define BITS_PER_U64 (sizeof(u64) * 8)
27
28static struct kmem_cache *ebitmap_node_cachep;
29
30int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2)
31{
32 struct ebitmap_node *n1, *n2;
33
34 if (e1->highbit != e2->highbit)
35 return 0;
36
37 n1 = e1->node;
38 n2 = e2->node;
39 while (n1 && n2 &&
40 (n1->startbit == n2->startbit) &&
41 !memcmp(n1->maps, n2->maps, EBITMAP_SIZE / 8)) {
42 n1 = n1->next;
43 n2 = n2->next;
44 }
45
46 if (n1 || n2)
47 return 0;
48
49 return 1;
50}
51
52int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src)
53{
54 struct ebitmap_node *n, *new, *prev;
55
56 ebitmap_init(dst);
57 n = src->node;
58 prev = NULL;
59 while (n) {
60 new = kmem_cache_zalloc(ebitmap_node_cachep, GFP_ATOMIC);
61 if (!new) {
62 ebitmap_destroy(dst);
63 return -ENOMEM;
64 }
65 new->startbit = n->startbit;
66 memcpy(new->maps, n->maps, EBITMAP_SIZE / 8);
67 new->next = NULL;
68 if (prev)
69 prev->next = new;
70 else
71 dst->node = new;
72 prev = new;
73 n = n->next;
74 }
75
76 dst->highbit = src->highbit;
77 return 0;
78}
79
80#ifdef CONFIG_NETLABEL
81/**
82 * ebitmap_netlbl_export - Export an ebitmap into a NetLabel category bitmap
83 * @ebmap: the ebitmap to export
84 * @catmap: the NetLabel category bitmap
85 *
86 * Description:
87 * Export a SELinux extensibile bitmap into a NetLabel category bitmap.
88 * Returns zero on success, negative values on error.
89 *
90 */
91int ebitmap_netlbl_export(struct ebitmap *ebmap,
92 struct netlbl_lsm_catmap **catmap)
93{
94 struct ebitmap_node *e_iter = ebmap->node;
95 unsigned long e_map;
96 u32 offset;
97 unsigned int iter;
98 int rc;
99
100 if (e_iter == NULL) {
101 *catmap = NULL;
102 return 0;
103 }
104
105 if (*catmap != NULL)
106 netlbl_catmap_free(*catmap);
107 *catmap = NULL;
108
109 while (e_iter) {
110 offset = e_iter->startbit;
111 for (iter = 0; iter < EBITMAP_UNIT_NUMS; iter++) {
112 e_map = e_iter->maps[iter];
113 if (e_map != 0) {
114 rc = netlbl_catmap_setlong(catmap,
115 offset,
116 e_map,
117 GFP_ATOMIC);
118 if (rc != 0)
119 goto netlbl_export_failure;
120 }
121 offset += EBITMAP_UNIT_SIZE;
122 }
123 e_iter = e_iter->next;
124 }
125
126 return 0;
127
128netlbl_export_failure:
129 netlbl_catmap_free(*catmap);
130 return -ENOMEM;
131}
132
133/**
134 * ebitmap_netlbl_import - Import a NetLabel category bitmap into an ebitmap
135 * @ebmap: the ebitmap to import
136 * @catmap: the NetLabel category bitmap
137 *
138 * Description:
139 * Import a NetLabel category bitmap into a SELinux extensibile bitmap.
140 * Returns zero on success, negative values on error.
141 *
142 */
143int ebitmap_netlbl_import(struct ebitmap *ebmap,
144 struct netlbl_lsm_catmap *catmap)
145{
146 int rc;
147 struct ebitmap_node *e_iter = NULL;
148 struct ebitmap_node *e_prev = NULL;
149 u32 offset = 0, idx;
150 unsigned long bitmap;
151
152 for (;;) {
153 rc = netlbl_catmap_getlong(catmap, &offset, &bitmap);
154 if (rc < 0)
155 goto netlbl_import_failure;
156 if (offset == (u32)-1)
157 return 0;
158
159 /* don't waste ebitmap space if the netlabel bitmap is empty */
160 if (bitmap == 0) {
161 offset += EBITMAP_UNIT_SIZE;
162 continue;
163 }
164
165 if (e_iter == NULL ||
166 offset >= e_iter->startbit + EBITMAP_SIZE) {
167 e_prev = e_iter;
168 e_iter = kmem_cache_zalloc(ebitmap_node_cachep, GFP_ATOMIC);
169 if (e_iter == NULL)
170 goto netlbl_import_failure;
171 e_iter->startbit = offset - (offset % EBITMAP_SIZE);
172 if (e_prev == NULL)
173 ebmap->node = e_iter;
174 else
175 e_prev->next = e_iter;
176 ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;
177 }
178
179 /* offset will always be aligned to an unsigned long */
180 idx = EBITMAP_NODE_INDEX(e_iter, offset);
181 e_iter->maps[idx] = bitmap;
182
183 /* next */
184 offset += EBITMAP_UNIT_SIZE;
185 }
186
187 /* NOTE: we should never reach this return */
188 return 0;
189
190netlbl_import_failure:
191 ebitmap_destroy(ebmap);
192 return -ENOMEM;
193}
194#endif /* CONFIG_NETLABEL */
195
196/*
197 * Check to see if all the bits set in e2 are also set in e1. Optionally,
198 * if last_e2bit is non-zero, the highest set bit in e2 cannot exceed
199 * last_e2bit.
200 */
201int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2, u32 last_e2bit)
202{
203 struct ebitmap_node *n1, *n2;
204 int i;
205
206 if (e1->highbit < e2->highbit)
207 return 0;
208
209 n1 = e1->node;
210 n2 = e2->node;
211
212 while (n1 && n2 && (n1->startbit <= n2->startbit)) {
213 if (n1->startbit < n2->startbit) {
214 n1 = n1->next;
215 continue;
216 }
217 for (i = EBITMAP_UNIT_NUMS - 1; (i >= 0) && !n2->maps[i]; )
218 i--; /* Skip trailing NULL map entries */
219 if (last_e2bit && (i >= 0)) {
220 u32 lastsetbit = n2->startbit + i * EBITMAP_UNIT_SIZE +
221 __fls(n2->maps[i]);
222 if (lastsetbit > last_e2bit)
223 return 0;
224 }
225
226 while (i >= 0) {
227 if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])
228 return 0;
229 i--;
230 }
231
232 n1 = n1->next;
233 n2 = n2->next;
234 }
235
236 if (n2)
237 return 0;
238
239 return 1;
240}
241
242int ebitmap_get_bit(struct ebitmap *e, unsigned long bit)
243{
244 struct ebitmap_node *n;
245
246 if (e->highbit < bit)
247 return 0;
248
249 n = e->node;
250 while (n && (n->startbit <= bit)) {
251 if ((n->startbit + EBITMAP_SIZE) > bit)
252 return ebitmap_node_get_bit(n, bit);
253 n = n->next;
254 }
255
256 return 0;
257}
258
259int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value)
260{
261 struct ebitmap_node *n, *prev, *new;
262
263 prev = NULL;
264 n = e->node;
265 while (n && n->startbit <= bit) {
266 if ((n->startbit + EBITMAP_SIZE) > bit) {
267 if (value) {
268 ebitmap_node_set_bit(n, bit);
269 } else {
270 unsigned int s;
271
272 ebitmap_node_clr_bit(n, bit);
273
274 s = find_first_bit(n->maps, EBITMAP_SIZE);
275 if (s < EBITMAP_SIZE)
276 return 0;
277
278 /* drop this node from the bitmap */
279 if (!n->next) {
280 /*
281 * this was the highest map
282 * within the bitmap
283 */
284 if (prev)
285 e->highbit = prev->startbit
286 + EBITMAP_SIZE;
287 else
288 e->highbit = 0;
289 }
290 if (prev)
291 prev->next = n->next;
292 else
293 e->node = n->next;
294 kmem_cache_free(ebitmap_node_cachep, n);
295 }
296 return 0;
297 }
298 prev = n;
299 n = n->next;
300 }
301
302 if (!value)
303 return 0;
304
305 new = kmem_cache_zalloc(ebitmap_node_cachep, GFP_ATOMIC);
306 if (!new)
307 return -ENOMEM;
308
309 new->startbit = bit - (bit % EBITMAP_SIZE);
310 ebitmap_node_set_bit(new, bit);
311
312 if (!n)
313 /* this node will be the highest map within the bitmap */
314 e->highbit = new->startbit + EBITMAP_SIZE;
315
316 if (prev) {
317 new->next = prev->next;
318 prev->next = new;
319 } else {
320 new->next = e->node;
321 e->node = new;
322 }
323
324 return 0;
325}
326
327void ebitmap_destroy(struct ebitmap *e)
328{
329 struct ebitmap_node *n, *temp;
330
331 if (!e)
332 return;
333
334 n = e->node;
335 while (n) {
336 temp = n;
337 n = n->next;
338 kmem_cache_free(ebitmap_node_cachep, temp);
339 }
340
341 e->highbit = 0;
342 e->node = NULL;
343 return;
344}
345
346int ebitmap_read(struct ebitmap *e, void *fp)
347{
348 struct ebitmap_node *n = NULL;
349 u32 mapunit, count, startbit, index;
350 __le32 ebitmap_start;
351 u64 map;
352 __le64 mapbits;
353 __le32 buf[3];
354 int rc, i;
355
356 ebitmap_init(e);
357
358 rc = next_entry(buf, fp, sizeof buf);
359 if (rc < 0)
360 goto out;
361
362 mapunit = le32_to_cpu(buf[0]);
363 e->highbit = le32_to_cpu(buf[1]);
364 count = le32_to_cpu(buf[2]);
365
366 if (mapunit != BITS_PER_U64) {
367 pr_err("SELinux: ebitmap: map size %u does not "
368 "match my size %zd (high bit was %d)\n",
369 mapunit, BITS_PER_U64, e->highbit);
370 goto bad;
371 }
372
373 /* round up e->highbit */
374 e->highbit += EBITMAP_SIZE - 1;
375 e->highbit -= (e->highbit % EBITMAP_SIZE);
376
377 if (!e->highbit) {
378 e->node = NULL;
379 goto ok;
380 }
381
382 if (e->highbit && !count)
383 goto bad;
384
385 for (i = 0; i < count; i++) {
386 rc = next_entry(&ebitmap_start, fp, sizeof(u32));
387 if (rc < 0) {
388 pr_err("SELinux: ebitmap: truncated map\n");
389 goto bad;
390 }
391 startbit = le32_to_cpu(ebitmap_start);
392
393 if (startbit & (mapunit - 1)) {
394 pr_err("SELinux: ebitmap start bit (%d) is "
395 "not a multiple of the map unit size (%u)\n",
396 startbit, mapunit);
397 goto bad;
398 }
399 if (startbit > e->highbit - mapunit) {
400 pr_err("SELinux: ebitmap start bit (%d) is "
401 "beyond the end of the bitmap (%u)\n",
402 startbit, (e->highbit - mapunit));
403 goto bad;
404 }
405
406 if (!n || startbit >= n->startbit + EBITMAP_SIZE) {
407 struct ebitmap_node *tmp;
408 tmp = kmem_cache_zalloc(ebitmap_node_cachep, GFP_KERNEL);
409 if (!tmp) {
410 pr_err("SELinux: ebitmap: out of memory\n");
411 rc = -ENOMEM;
412 goto bad;
413 }
414 /* round down */
415 tmp->startbit = startbit - (startbit % EBITMAP_SIZE);
416 if (n)
417 n->next = tmp;
418 else
419 e->node = tmp;
420 n = tmp;
421 } else if (startbit <= n->startbit) {
422 pr_err("SELinux: ebitmap: start bit %d"
423 " comes after start bit %d\n",
424 startbit, n->startbit);
425 goto bad;
426 }
427
428 rc = next_entry(&mapbits, fp, sizeof(u64));
429 if (rc < 0) {
430 pr_err("SELinux: ebitmap: truncated map\n");
431 goto bad;
432 }
433 map = le64_to_cpu(mapbits);
434
435 index = (startbit - n->startbit) / EBITMAP_UNIT_SIZE;
436 while (map) {
437 n->maps[index++] = map & (-1UL);
438 map = EBITMAP_SHIFT_UNIT_SIZE(map);
439 }
440 }
441ok:
442 rc = 0;
443out:
444 return rc;
445bad:
446 if (!rc)
447 rc = -EINVAL;
448 ebitmap_destroy(e);
449 goto out;
450}
451
452int ebitmap_write(struct ebitmap *e, void *fp)
453{
454 struct ebitmap_node *n;
455 u32 count;
456 __le32 buf[3];
457 u64 map;
458 int bit, last_bit, last_startbit, rc;
459
460 buf[0] = cpu_to_le32(BITS_PER_U64);
461
462 count = 0;
463 last_bit = 0;
464 last_startbit = -1;
465 ebitmap_for_each_positive_bit(e, n, bit) {
466 if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) {
467 count++;
468 last_startbit = rounddown(bit, BITS_PER_U64);
469 }
470 last_bit = roundup(bit + 1, BITS_PER_U64);
471 }
472 buf[1] = cpu_to_le32(last_bit);
473 buf[2] = cpu_to_le32(count);
474
475 rc = put_entry(buf, sizeof(u32), 3, fp);
476 if (rc)
477 return rc;
478
479 map = 0;
480 last_startbit = INT_MIN;
481 ebitmap_for_each_positive_bit(e, n, bit) {
482 if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) {
483 __le64 buf64[1];
484
485 /* this is the very first bit */
486 if (!map) {
487 last_startbit = rounddown(bit, BITS_PER_U64);
488 map = (u64)1 << (bit - last_startbit);
489 continue;
490 }
491
492 /* write the last node */
493 buf[0] = cpu_to_le32(last_startbit);
494 rc = put_entry(buf, sizeof(u32), 1, fp);
495 if (rc)
496 return rc;
497
498 buf64[0] = cpu_to_le64(map);
499 rc = put_entry(buf64, sizeof(u64), 1, fp);
500 if (rc)
501 return rc;
502
503 /* set up for the next node */
504 map = 0;
505 last_startbit = rounddown(bit, BITS_PER_U64);
506 }
507 map |= (u64)1 << (bit - last_startbit);
508 }
509 /* write the last node */
510 if (map) {
511 __le64 buf64[1];
512
513 /* write the last node */
514 buf[0] = cpu_to_le32(last_startbit);
515 rc = put_entry(buf, sizeof(u32), 1, fp);
516 if (rc)
517 return rc;
518
519 buf64[0] = cpu_to_le64(map);
520 rc = put_entry(buf64, sizeof(u64), 1, fp);
521 if (rc)
522 return rc;
523 }
524 return 0;
525}
526
527void __init ebitmap_cache_init(void)
528{
529 ebitmap_node_cachep = kmem_cache_create("ebitmap_node",
530 sizeof(struct ebitmap_node),
531 0, SLAB_PANIC, NULL);
532}