Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Implementation of the multi-level security (MLS) policy. | |
3 | * | |
4 | * Author : Stephen Smalley, <sds@epoch.ncsc.mil> | |
5 | */ | |
6 | /* | |
7 | * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> | |
8 | * | |
9 | * Support for enhanced MLS infrastructure. | |
10 | * | |
376bd9cb | 11 | * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. |
1da177e4 | 12 | */ |
7420ed23 VY |
13 | /* |
14 | * Updated: Hewlett-Packard <paul.moore@hp.com> | |
15 | * | |
16 | * Added support to import/export the MLS label | |
17 | * | |
18 | * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 | |
19 | */ | |
1da177e4 LT |
20 | |
21 | #include <linux/kernel.h> | |
22 | #include <linux/slab.h> | |
23 | #include <linux/string.h> | |
24 | #include <linux/errno.h> | |
f5c1d5b2 | 25 | #include "sidtab.h" |
1da177e4 LT |
26 | #include "mls.h" |
27 | #include "policydb.h" | |
28 | #include "services.h" | |
29 | ||
30 | /* | |
31 | * Return the length in bytes for the MLS fields of the | |
32 | * security context string representation of `context'. | |
33 | */ | |
34 | int mls_compute_context_len(struct context * context) | |
35 | { | |
36 | int i, l, len, range; | |
782ebb99 | 37 | struct ebitmap_node *node; |
1da177e4 LT |
38 | |
39 | if (!selinux_mls_enabled) | |
40 | return 0; | |
41 | ||
42 | len = 1; /* for the beginning ":" */ | |
43 | for (l = 0; l < 2; l++) { | |
44 | range = 0; | |
45 | len += strlen(policydb.p_sens_val_to_name[context->range.level[l].sens - 1]); | |
46 | ||
782ebb99 SS |
47 | ebitmap_for_each_bit(&context->range.level[l].cat, node, i) { |
48 | if (ebitmap_node_get_bit(node, i)) { | |
1da177e4 LT |
49 | if (range) { |
50 | range++; | |
51 | continue; | |
52 | } | |
53 | ||
782ebb99 | 54 | len += strlen(policydb.p_cat_val_to_name[i]) + 1; |
1da177e4 LT |
55 | range++; |
56 | } else { | |
57 | if (range > 1) | |
782ebb99 | 58 | len += strlen(policydb.p_cat_val_to_name[i - 1]) + 1; |
1da177e4 LT |
59 | range = 0; |
60 | } | |
61 | } | |
62 | /* Handle case where last category is the end of range */ | |
63 | if (range > 1) | |
782ebb99 | 64 | len += strlen(policydb.p_cat_val_to_name[i - 1]) + 1; |
1da177e4 LT |
65 | |
66 | if (l == 0) { | |
67 | if (mls_level_eq(&context->range.level[0], | |
68 | &context->range.level[1])) | |
69 | break; | |
70 | else | |
71 | len++; | |
72 | } | |
73 | } | |
74 | ||
75 | return len; | |
76 | } | |
77 | ||
78 | /* | |
79 | * Write the security context string representation of | |
80 | * the MLS fields of `context' into the string `*scontext'. | |
81 | * Update `*scontext' to point to the end of the MLS fields. | |
82 | */ | |
83 | void mls_sid_to_context(struct context *context, | |
84 | char **scontext) | |
85 | { | |
86 | char *scontextp; | |
87 | int i, l, range, wrote_sep; | |
782ebb99 | 88 | struct ebitmap_node *node; |
1da177e4 LT |
89 | |
90 | if (!selinux_mls_enabled) | |
91 | return; | |
92 | ||
93 | scontextp = *scontext; | |
94 | ||
95 | *scontextp = ':'; | |
96 | scontextp++; | |
97 | ||
98 | for (l = 0; l < 2; l++) { | |
99 | range = 0; | |
100 | wrote_sep = 0; | |
101 | strcpy(scontextp, | |
102 | policydb.p_sens_val_to_name[context->range.level[l].sens - 1]); | |
103 | scontextp += strlen(policydb.p_sens_val_to_name[context->range.level[l].sens - 1]); | |
104 | ||
105 | /* categories */ | |
782ebb99 SS |
106 | ebitmap_for_each_bit(&context->range.level[l].cat, node, i) { |
107 | if (ebitmap_node_get_bit(node, i)) { | |
1da177e4 LT |
108 | if (range) { |
109 | range++; | |
110 | continue; | |
111 | } | |
112 | ||
113 | if (!wrote_sep) { | |
114 | *scontextp++ = ':'; | |
115 | wrote_sep = 1; | |
116 | } else | |
117 | *scontextp++ = ','; | |
782ebb99 SS |
118 | strcpy(scontextp, policydb.p_cat_val_to_name[i]); |
119 | scontextp += strlen(policydb.p_cat_val_to_name[i]); | |
1da177e4 LT |
120 | range++; |
121 | } else { | |
122 | if (range > 1) { | |
123 | if (range > 2) | |
124 | *scontextp++ = '.'; | |
125 | else | |
126 | *scontextp++ = ','; | |
127 | ||
782ebb99 SS |
128 | strcpy(scontextp, policydb.p_cat_val_to_name[i - 1]); |
129 | scontextp += strlen(policydb.p_cat_val_to_name[i - 1]); | |
1da177e4 LT |
130 | } |
131 | range = 0; | |
132 | } | |
133 | } | |
134 | ||
135 | /* Handle case where last category is the end of range */ | |
136 | if (range > 1) { | |
137 | if (range > 2) | |
138 | *scontextp++ = '.'; | |
139 | else | |
140 | *scontextp++ = ','; | |
141 | ||
782ebb99 SS |
142 | strcpy(scontextp, policydb.p_cat_val_to_name[i - 1]); |
143 | scontextp += strlen(policydb.p_cat_val_to_name[i - 1]); | |
1da177e4 LT |
144 | } |
145 | ||
146 | if (l == 0) { | |
147 | if (mls_level_eq(&context->range.level[0], | |
148 | &context->range.level[1])) | |
149 | break; | |
150 | else { | |
151 | *scontextp = '-'; | |
152 | scontextp++; | |
153 | } | |
154 | } | |
155 | } | |
156 | ||
157 | *scontext = scontextp; | |
158 | return; | |
159 | } | |
160 | ||
161 | /* | |
162 | * Return 1 if the MLS fields in the security context | |
163 | * structure `c' are valid. Return 0 otherwise. | |
164 | */ | |
165 | int mls_context_isvalid(struct policydb *p, struct context *c) | |
166 | { | |
167 | struct level_datum *levdatum; | |
168 | struct user_datum *usrdatum; | |
782ebb99 | 169 | struct ebitmap_node *node; |
1da177e4 LT |
170 | int i, l; |
171 | ||
172 | if (!selinux_mls_enabled) | |
173 | return 1; | |
174 | ||
175 | /* | |
176 | * MLS range validity checks: high must dominate low, low level must | |
177 | * be valid (category set <-> sensitivity check), and high level must | |
178 | * be valid (category set <-> sensitivity check) | |
179 | */ | |
180 | if (!mls_level_dom(&c->range.level[1], &c->range.level[0])) | |
181 | /* High does not dominate low. */ | |
182 | return 0; | |
183 | ||
184 | for (l = 0; l < 2; l++) { | |
185 | if (!c->range.level[l].sens || c->range.level[l].sens > p->p_levels.nprim) | |
186 | return 0; | |
187 | levdatum = hashtab_search(p->p_levels.table, | |
188 | p->p_sens_val_to_name[c->range.level[l].sens - 1]); | |
189 | if (!levdatum) | |
190 | return 0; | |
191 | ||
782ebb99 SS |
192 | ebitmap_for_each_bit(&c->range.level[l].cat, node, i) { |
193 | if (ebitmap_node_get_bit(node, i)) { | |
1da177e4 LT |
194 | if (i > p->p_cats.nprim) |
195 | return 0; | |
782ebb99 | 196 | if (!ebitmap_get_bit(&levdatum->level->cat, i)) |
1da177e4 LT |
197 | /* |
198 | * Category may not be associated with | |
199 | * sensitivity in low level. | |
200 | */ | |
201 | return 0; | |
202 | } | |
203 | } | |
204 | } | |
205 | ||
206 | if (c->role == OBJECT_R_VAL) | |
207 | return 1; | |
208 | ||
209 | /* | |
210 | * User must be authorized for the MLS range. | |
211 | */ | |
212 | if (!c->user || c->user > p->p_users.nprim) | |
213 | return 0; | |
214 | usrdatum = p->user_val_to_struct[c->user - 1]; | |
215 | if (!mls_range_contains(usrdatum->range, c->range)) | |
216 | return 0; /* user may not be associated with range */ | |
217 | ||
218 | return 1; | |
219 | } | |
220 | ||
221 | /* | |
222 | * Set the MLS fields in the security context structure | |
223 | * `context' based on the string representation in | |
224 | * the string `*scontext'. Update `*scontext' to | |
225 | * point to the end of the string representation of | |
226 | * the MLS fields. | |
227 | * | |
228 | * This function modifies the string in place, inserting | |
229 | * NULL characters to terminate the MLS fields. | |
f5c1d5b2 JM |
230 | * |
231 | * If a def_sid is provided and no MLS field is present, | |
232 | * copy the MLS field of the associated default context. | |
233 | * Used for upgraded to MLS systems where objects may lack | |
234 | * MLS fields. | |
235 | * | |
236 | * Policy read-lock must be held for sidtab lookup. | |
237 | * | |
1da177e4 LT |
238 | */ |
239 | int mls_context_to_sid(char oldc, | |
240 | char **scontext, | |
f5c1d5b2 JM |
241 | struct context *context, |
242 | struct sidtab *s, | |
243 | u32 def_sid) | |
1da177e4 LT |
244 | { |
245 | ||
246 | char delim; | |
247 | char *scontextp, *p, *rngptr; | |
248 | struct level_datum *levdatum; | |
249 | struct cat_datum *catdatum, *rngdatum; | |
250 | int l, rc = -EINVAL; | |
251 | ||
e517a0cd SS |
252 | if (!selinux_mls_enabled) { |
253 | if (def_sid != SECSID_NULL && oldc) | |
ab5703b3 | 254 | *scontext += strlen(*scontext)+1; |
1da177e4 | 255 | return 0; |
e517a0cd | 256 | } |
1da177e4 | 257 | |
f5c1d5b2 JM |
258 | /* |
259 | * No MLS component to the security context, try and map to | |
260 | * default if provided. | |
261 | */ | |
262 | if (!oldc) { | |
263 | struct context *defcon; | |
264 | ||
265 | if (def_sid == SECSID_NULL) | |
266 | goto out; | |
267 | ||
268 | defcon = sidtab_search(s, def_sid); | |
269 | if (!defcon) | |
270 | goto out; | |
271 | ||
272 | rc = mls_copy_context(context, defcon); | |
1da177e4 | 273 | goto out; |
f5c1d5b2 | 274 | } |
1da177e4 LT |
275 | |
276 | /* Extract low sensitivity. */ | |
277 | scontextp = p = *scontext; | |
278 | while (*p && *p != ':' && *p != '-') | |
279 | p++; | |
280 | ||
281 | delim = *p; | |
282 | if (delim != 0) | |
283 | *p++ = 0; | |
284 | ||
285 | for (l = 0; l < 2; l++) { | |
286 | levdatum = hashtab_search(policydb.p_levels.table, scontextp); | |
287 | if (!levdatum) { | |
288 | rc = -EINVAL; | |
289 | goto out; | |
290 | } | |
291 | ||
292 | context->range.level[l].sens = levdatum->level->sens; | |
293 | ||
294 | if (delim == ':') { | |
295 | /* Extract category set. */ | |
296 | while (1) { | |
297 | scontextp = p; | |
298 | while (*p && *p != ',' && *p != '-') | |
299 | p++; | |
300 | delim = *p; | |
301 | if (delim != 0) | |
302 | *p++ = 0; | |
303 | ||
304 | /* Separate into range if exists */ | |
305 | if ((rngptr = strchr(scontextp, '.')) != NULL) { | |
306 | /* Remove '.' */ | |
307 | *rngptr++ = 0; | |
308 | } | |
309 | ||
310 | catdatum = hashtab_search(policydb.p_cats.table, | |
311 | scontextp); | |
312 | if (!catdatum) { | |
313 | rc = -EINVAL; | |
314 | goto out; | |
315 | } | |
316 | ||
317 | rc = ebitmap_set_bit(&context->range.level[l].cat, | |
318 | catdatum->value - 1, 1); | |
319 | if (rc) | |
320 | goto out; | |
321 | ||
322 | /* If range, set all categories in range */ | |
323 | if (rngptr) { | |
324 | int i; | |
325 | ||
326 | rngdatum = hashtab_search(policydb.p_cats.table, rngptr); | |
327 | if (!rngdatum) { | |
328 | rc = -EINVAL; | |
329 | goto out; | |
330 | } | |
331 | ||
332 | if (catdatum->value >= rngdatum->value) { | |
333 | rc = -EINVAL; | |
334 | goto out; | |
335 | } | |
336 | ||
337 | for (i = catdatum->value; i < rngdatum->value; i++) { | |
338 | rc = ebitmap_set_bit(&context->range.level[l].cat, i, 1); | |
339 | if (rc) | |
340 | goto out; | |
341 | } | |
342 | } | |
343 | ||
344 | if (delim != ',') | |
345 | break; | |
346 | } | |
347 | } | |
348 | if (delim == '-') { | |
349 | /* Extract high sensitivity. */ | |
350 | scontextp = p; | |
351 | while (*p && *p != ':') | |
352 | p++; | |
353 | ||
354 | delim = *p; | |
355 | if (delim != 0) | |
356 | *p++ = 0; | |
357 | } else | |
358 | break; | |
359 | } | |
360 | ||
361 | if (l == 0) { | |
362 | context->range.level[1].sens = context->range.level[0].sens; | |
363 | rc = ebitmap_cpy(&context->range.level[1].cat, | |
364 | &context->range.level[0].cat); | |
365 | if (rc) | |
366 | goto out; | |
367 | } | |
368 | *scontext = ++p; | |
369 | rc = 0; | |
370 | out: | |
371 | return rc; | |
372 | } | |
373 | ||
376bd9cb DG |
374 | /* |
375 | * Set the MLS fields in the security context structure | |
376 | * `context' based on the string representation in | |
377 | * the string `str'. This function will allocate temporary memory with the | |
378 | * given constraints of gfp_mask. | |
379 | */ | |
380 | int mls_from_string(char *str, struct context *context, gfp_t gfp_mask) | |
381 | { | |
382 | char *tmpstr, *freestr; | |
383 | int rc; | |
384 | ||
385 | if (!selinux_mls_enabled) | |
386 | return -EINVAL; | |
387 | ||
388 | /* we need freestr because mls_context_to_sid will change | |
389 | the value of tmpstr */ | |
390 | tmpstr = freestr = kstrdup(str, gfp_mask); | |
391 | if (!tmpstr) { | |
392 | rc = -ENOMEM; | |
393 | } else { | |
394 | rc = mls_context_to_sid(':', &tmpstr, context, | |
395 | NULL, SECSID_NULL); | |
396 | kfree(freestr); | |
397 | } | |
398 | ||
399 | return rc; | |
400 | } | |
401 | ||
1da177e4 LT |
402 | /* |
403 | * Copies the effective MLS range from `src' into `dst'. | |
404 | */ | |
405 | static inline int mls_scopy_context(struct context *dst, | |
406 | struct context *src) | |
407 | { | |
408 | int l, rc = 0; | |
409 | ||
410 | /* Copy the MLS range from the source context */ | |
411 | for (l = 0; l < 2; l++) { | |
412 | dst->range.level[l].sens = src->range.level[0].sens; | |
413 | rc = ebitmap_cpy(&dst->range.level[l].cat, | |
414 | &src->range.level[0].cat); | |
415 | if (rc) | |
416 | break; | |
417 | } | |
418 | ||
419 | return rc; | |
420 | } | |
421 | ||
422 | /* | |
423 | * Copies the MLS range `range' into `context'. | |
424 | */ | |
425 | static inline int mls_range_set(struct context *context, | |
426 | struct mls_range *range) | |
427 | { | |
428 | int l, rc = 0; | |
429 | ||
430 | /* Copy the MLS range into the context */ | |
431 | for (l = 0; l < 2; l++) { | |
432 | context->range.level[l].sens = range->level[l].sens; | |
433 | rc = ebitmap_cpy(&context->range.level[l].cat, | |
434 | &range->level[l].cat); | |
435 | if (rc) | |
436 | break; | |
437 | } | |
438 | ||
439 | return rc; | |
440 | } | |
441 | ||
442 | int mls_setup_user_range(struct context *fromcon, struct user_datum *user, | |
443 | struct context *usercon) | |
444 | { | |
445 | if (selinux_mls_enabled) { | |
446 | struct mls_level *fromcon_sen = &(fromcon->range.level[0]); | |
447 | struct mls_level *fromcon_clr = &(fromcon->range.level[1]); | |
448 | struct mls_level *user_low = &(user->range.level[0]); | |
449 | struct mls_level *user_clr = &(user->range.level[1]); | |
450 | struct mls_level *user_def = &(user->dfltlevel); | |
451 | struct mls_level *usercon_sen = &(usercon->range.level[0]); | |
452 | struct mls_level *usercon_clr = &(usercon->range.level[1]); | |
453 | ||
454 | /* Honor the user's default level if we can */ | |
455 | if (mls_level_between(user_def, fromcon_sen, fromcon_clr)) { | |
456 | *usercon_sen = *user_def; | |
457 | } else if (mls_level_between(fromcon_sen, user_def, user_clr)) { | |
458 | *usercon_sen = *fromcon_sen; | |
459 | } else if (mls_level_between(fromcon_clr, user_low, user_def)) { | |
460 | *usercon_sen = *user_low; | |
461 | } else | |
462 | return -EINVAL; | |
463 | ||
464 | /* Lower the clearance of available contexts | |
465 | if the clearance of "fromcon" is lower than | |
466 | that of the user's default clearance (but | |
467 | only if the "fromcon" clearance dominates | |
468 | the user's computed sensitivity level) */ | |
469 | if (mls_level_dom(user_clr, fromcon_clr)) { | |
470 | *usercon_clr = *fromcon_clr; | |
471 | } else if (mls_level_dom(fromcon_clr, user_clr)) { | |
472 | *usercon_clr = *user_clr; | |
473 | } else | |
474 | return -EINVAL; | |
475 | } | |
476 | ||
477 | return 0; | |
478 | } | |
479 | ||
480 | /* | |
481 | * Convert the MLS fields in the security context | |
482 | * structure `c' from the values specified in the | |
483 | * policy `oldp' to the values specified in the policy `newp'. | |
484 | */ | |
485 | int mls_convert_context(struct policydb *oldp, | |
486 | struct policydb *newp, | |
487 | struct context *c) | |
488 | { | |
489 | struct level_datum *levdatum; | |
490 | struct cat_datum *catdatum; | |
491 | struct ebitmap bitmap; | |
782ebb99 | 492 | struct ebitmap_node *node; |
1da177e4 LT |
493 | int l, i; |
494 | ||
495 | if (!selinux_mls_enabled) | |
496 | return 0; | |
497 | ||
498 | for (l = 0; l < 2; l++) { | |
499 | levdatum = hashtab_search(newp->p_levels.table, | |
500 | oldp->p_sens_val_to_name[c->range.level[l].sens - 1]); | |
501 | ||
502 | if (!levdatum) | |
503 | return -EINVAL; | |
504 | c->range.level[l].sens = levdatum->level->sens; | |
505 | ||
506 | ebitmap_init(&bitmap); | |
782ebb99 SS |
507 | ebitmap_for_each_bit(&c->range.level[l].cat, node, i) { |
508 | if (ebitmap_node_get_bit(node, i)) { | |
1da177e4 LT |
509 | int rc; |
510 | ||
511 | catdatum = hashtab_search(newp->p_cats.table, | |
782ebb99 | 512 | oldp->p_cat_val_to_name[i]); |
1da177e4 LT |
513 | if (!catdatum) |
514 | return -EINVAL; | |
515 | rc = ebitmap_set_bit(&bitmap, catdatum->value - 1, 1); | |
516 | if (rc) | |
517 | return rc; | |
518 | } | |
519 | } | |
520 | ebitmap_destroy(&c->range.level[l].cat); | |
521 | c->range.level[l].cat = bitmap; | |
522 | } | |
523 | ||
524 | return 0; | |
525 | } | |
526 | ||
527 | int mls_compute_sid(struct context *scontext, | |
528 | struct context *tcontext, | |
529 | u16 tclass, | |
530 | u32 specified, | |
531 | struct context *newcontext) | |
532 | { | |
f3f87714 DG |
533 | struct range_trans *rtr; |
534 | ||
1da177e4 LT |
535 | if (!selinux_mls_enabled) |
536 | return 0; | |
537 | ||
538 | switch (specified) { | |
539 | case AVTAB_TRANSITION: | |
f3f87714 DG |
540 | /* Look for a range transition rule. */ |
541 | for (rtr = policydb.range_tr; rtr; rtr = rtr->next) { | |
542 | if (rtr->source_type == scontext->type && | |
543 | rtr->target_type == tcontext->type && | |
544 | rtr->target_class == tclass) { | |
545 | /* Set the range from the rule */ | |
546 | return mls_range_set(newcontext, | |
547 | &rtr->target_range); | |
1da177e4 LT |
548 | } |
549 | } | |
550 | /* Fallthrough */ | |
551 | case AVTAB_CHANGE: | |
552 | if (tclass == SECCLASS_PROCESS) | |
553 | /* Use the process MLS attributes. */ | |
554 | return mls_copy_context(newcontext, scontext); | |
555 | else | |
556 | /* Use the process effective MLS attributes. */ | |
557 | return mls_scopy_context(newcontext, scontext); | |
558 | case AVTAB_MEMBER: | |
559 | /* Only polyinstantiate the MLS attributes if | |
560 | the type is being polyinstantiated */ | |
561 | if (newcontext->type != tcontext->type) { | |
562 | /* Use the process effective MLS attributes. */ | |
563 | return mls_scopy_context(newcontext, scontext); | |
564 | } else { | |
565 | /* Use the related object MLS attributes. */ | |
566 | return mls_copy_context(newcontext, tcontext); | |
567 | } | |
568 | default: | |
569 | return -EINVAL; | |
570 | } | |
571 | return -EINVAL; | |
572 | } | |
573 | ||
7420ed23 VY |
574 | /** |
575 | * mls_export_lvl - Export the MLS sensitivity levels | |
576 | * @context: the security context | |
577 | * @low: the low sensitivity level | |
578 | * @high: the high sensitivity level | |
579 | * | |
580 | * Description: | |
581 | * Given the security context copy the low MLS sensitivity level into lvl_low | |
582 | * and the high sensitivity level in lvl_high. The MLS levels are only | |
583 | * exported if the pointers are not NULL, if they are NULL then that level is | |
584 | * not exported. | |
585 | * | |
586 | */ | |
587 | void mls_export_lvl(const struct context *context, u32 *low, u32 *high) | |
588 | { | |
589 | if (!selinux_mls_enabled) | |
590 | return; | |
591 | ||
592 | if (low != NULL) | |
593 | *low = context->range.level[0].sens - 1; | |
594 | if (high != NULL) | |
595 | *high = context->range.level[1].sens - 1; | |
596 | } | |
597 | ||
598 | /** | |
599 | * mls_import_lvl - Import the MLS sensitivity levels | |
600 | * @context: the security context | |
601 | * @low: the low sensitivity level | |
602 | * @high: the high sensitivity level | |
603 | * | |
604 | * Description: | |
605 | * Given the security context and the two sensitivty levels, set the MLS levels | |
606 | * in the context according the two given as parameters. Returns zero on | |
607 | * success, negative values on failure. | |
608 | * | |
609 | */ | |
610 | void mls_import_lvl(struct context *context, u32 low, u32 high) | |
611 | { | |
612 | if (!selinux_mls_enabled) | |
613 | return; | |
614 | ||
615 | context->range.level[0].sens = low + 1; | |
616 | context->range.level[1].sens = high + 1; | |
617 | } | |
618 | ||
619 | /** | |
620 | * mls_export_cat - Export the MLS categories | |
621 | * @context: the security context | |
622 | * @low: the low category | |
623 | * @low_len: length of the cat_low bitmap in bytes | |
624 | * @high: the high category | |
625 | * @high_len: length of the cat_high bitmap in bytes | |
626 | * | |
627 | * Description: | |
628 | * Given the security context export the low MLS category bitmap into cat_low | |
629 | * and the high category bitmap into cat_high. The MLS categories are only | |
630 | * exported if the pointers are not NULL, if they are NULL then that level is | |
631 | * not exported. The caller is responsibile for freeing the memory when | |
632 | * finished. Returns zero on success, negative values on failure. | |
633 | * | |
634 | */ | |
635 | int mls_export_cat(const struct context *context, | |
636 | unsigned char **low, | |
637 | size_t *low_len, | |
638 | unsigned char **high, | |
639 | size_t *high_len) | |
640 | { | |
641 | int rc = -EPERM; | |
642 | ||
bf0edf39 PM |
643 | if (!selinux_mls_enabled) { |
644 | *low = NULL; | |
645 | *low_len = 0; | |
646 | *high = NULL; | |
647 | *high_len = 0; | |
7420ed23 | 648 | return 0; |
bf0edf39 | 649 | } |
7420ed23 VY |
650 | |
651 | if (low != NULL) { | |
652 | rc = ebitmap_export(&context->range.level[0].cat, | |
653 | low, | |
654 | low_len); | |
655 | if (rc != 0) | |
656 | goto export_cat_failure; | |
657 | } | |
658 | if (high != NULL) { | |
659 | rc = ebitmap_export(&context->range.level[1].cat, | |
660 | high, | |
661 | high_len); | |
662 | if (rc != 0) | |
663 | goto export_cat_failure; | |
664 | } | |
665 | ||
666 | return 0; | |
667 | ||
668 | export_cat_failure: | |
bf0edf39 | 669 | if (low != NULL) { |
7420ed23 | 670 | kfree(*low); |
bf0edf39 PM |
671 | *low = NULL; |
672 | *low_len = 0; | |
673 | } | |
674 | if (high != NULL) { | |
7420ed23 | 675 | kfree(*high); |
bf0edf39 PM |
676 | *high = NULL; |
677 | *high_len = 0; | |
678 | } | |
7420ed23 VY |
679 | return rc; |
680 | } | |
681 | ||
682 | /** | |
683 | * mls_import_cat - Import the MLS categories | |
684 | * @context: the security context | |
685 | * @low: the low category | |
686 | * @low_len: length of the cat_low bitmap in bytes | |
687 | * @high: the high category | |
688 | * @high_len: length of the cat_high bitmap in bytes | |
689 | * | |
690 | * Description: | |
691 | * Given the security context and the two category bitmap strings import the | |
692 | * categories into the security context. The MLS categories are only imported | |
693 | * if the pointers are not NULL, if they are NULL they are skipped. Returns | |
694 | * zero on success, negative values on failure. | |
695 | * | |
696 | */ | |
697 | int mls_import_cat(struct context *context, | |
698 | const unsigned char *low, | |
699 | size_t low_len, | |
700 | const unsigned char *high, | |
701 | size_t high_len) | |
702 | { | |
703 | int rc = -EPERM; | |
704 | ||
705 | if (!selinux_mls_enabled) | |
706 | return 0; | |
707 | ||
708 | if (low != NULL) { | |
709 | rc = ebitmap_import(low, | |
710 | low_len, | |
711 | &context->range.level[0].cat); | |
712 | if (rc != 0) | |
713 | goto import_cat_failure; | |
714 | } | |
715 | if (high != NULL) { | |
716 | if (high == low) | |
717 | rc = ebitmap_cpy(&context->range.level[1].cat, | |
718 | &context->range.level[0].cat); | |
719 | else | |
720 | rc = ebitmap_import(high, | |
721 | high_len, | |
722 | &context->range.level[1].cat); | |
723 | if (rc != 0) | |
724 | goto import_cat_failure; | |
725 | } | |
726 | ||
727 | return 0; | |
728 | ||
729 | import_cat_failure: | |
730 | ebitmap_destroy(&context->range.level[0].cat); | |
731 | ebitmap_destroy(&context->range.level[1].cat); | |
732 | return rc; | |
733 | } |