Blame view
security/smack/smack_access.c
17.4 KB
a10e763b8 treewide: Replace... |
1 |
// SPDX-License-Identifier: GPL-2.0-only |
e114e4737 Smack: Simplified... |
2 3 4 |
/* * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> * |
e114e4737 Smack: Simplified... |
5 6 |
* Author: * Casey Schaufler <casey@schaufler-ca.com> |
e114e4737 Smack: Simplified... |
7 8 9 |
*/ #include <linux/types.h> |
5a0e3ad6a include cleanup: ... |
10 |
#include <linux/slab.h> |
e114e4737 Smack: Simplified... |
11 12 13 |
#include <linux/fs.h> #include <linux/sched.h> #include "smack.h" |
e114e4737 Smack: Simplified... |
14 |
struct smack_known smack_known_huh = { |
e114e4737 Smack: Simplified... |
15 16 |
.smk_known = "?", .smk_secid = 2, |
e114e4737 Smack: Simplified... |
17 18 19 |
}; struct smack_known smack_known_hat = { |
e114e4737 Smack: Simplified... |
20 21 |
.smk_known = "^", .smk_secid = 3, |
e114e4737 Smack: Simplified... |
22 23 24 |
}; struct smack_known smack_known_star = { |
e114e4737 Smack: Simplified... |
25 26 |
.smk_known = "*", .smk_secid = 4, |
e114e4737 Smack: Simplified... |
27 28 29 |
}; struct smack_known smack_known_floor = { |
e114e4737 Smack: Simplified... |
30 31 |
.smk_known = "_", .smk_secid = 5, |
e114e4737 Smack: Simplified... |
32 |
}; |
6d3dc07cb smack: Add suppor... |
33 |
struct smack_known smack_known_web = { |
6d3dc07cb smack: Add suppor... |
34 35 |
.smk_known = "@", .smk_secid = 7, |
6d3dc07cb smack: Add suppor... |
36 |
}; |
7198e2eeb smack: convert sm... |
37 |
LIST_HEAD(smack_known_list); |
e114e4737 Smack: Simplified... |
38 39 40 41 42 43 |
/* * The initial value needs to be bigger than any of the * known values above. */ static u32 smack_next_secid = 10; |
ecfcc53fe smack: implement ... |
44 45 46 47 48 |
/* * what events do we log * can be overwritten at run-time by /smack/logging */ int log_policy = SMACK_AUDIT_DENIED; |
e114e4737 Smack: Simplified... |
49 |
/** |
5c6d1125f Smack: Transmute ... |
50 51 52 |
* smk_access_entry - look up matching access rule * @subject_label: a pointer to the subject's Smack label * @object_label: a pointer to the object's Smack label |
7898e1f8e Subject: [PATCH] ... |
53 |
* @rule_list: the list of rules to search |
5c6d1125f Smack: Transmute ... |
54 55 |
* * This function looks up the subject/object pair in the |
7898e1f8e Subject: [PATCH] ... |
56 57 |
* access rule list and returns the access mode. If no * entry is found returns -ENOENT. |
5c6d1125f Smack: Transmute ... |
58 59 |
* * NOTE: |
5c6d1125f Smack: Transmute ... |
60 |
* |
272cd7a8c Smack: Rule list ... |
61 62 63 64 65 66 67 68 69 70 71 72 |
* Earlier versions of this function allowed for labels that * were not on the label list. This was done to allow for * labels to come over the network that had never been seen * before on this host. Unless the receiving socket has the * star label this will always result in a failure check. The * star labeled socket case is now handled in the networking * hooks so there is no case where the label is not on the * label list. Checking to see if the address of two labels * is the same is now a reliable test. * * Do the object check first because that is more * likely to differ. |
c0ab6e56d Smack: Implement ... |
73 74 |
* * Allowing write access implies allowing locking. |
5c6d1125f Smack: Transmute ... |
75 |
*/ |
7898e1f8e Subject: [PATCH] ... |
76 77 |
int smk_access_entry(char *subject_label, char *object_label, struct list_head *rule_list) |
5c6d1125f Smack: Transmute ... |
78 |
{ |
7898e1f8e Subject: [PATCH] ... |
79 |
int may = -ENOENT; |
5c6d1125f Smack: Transmute ... |
80 |
struct smack_rule *srp; |
7898e1f8e Subject: [PATCH] ... |
81 |
list_for_each_entry_rcu(srp, rule_list, list) { |
21c7eae21 Make Smack operat... |
82 |
if (srp->smk_object->smk_known == object_label && |
2f823ff8b Smack: Improve ac... |
83 |
srp->smk_subject->smk_known == subject_label) { |
272cd7a8c Smack: Rule list ... |
84 85 |
may = srp->smk_access; break; |
5c6d1125f Smack: Transmute ... |
86 87 |
} } |
5c6d1125f Smack: Transmute ... |
88 |
|
c0ab6e56d Smack: Implement ... |
89 90 91 92 93 |
/* * MAY_WRITE implies MAY_LOCK. */ if ((may & MAY_WRITE) == MAY_WRITE) may |= MAY_LOCK; |
5c6d1125f Smack: Transmute ... |
94 95 96 97 |
return may; } /** |
e114e4737 Smack: Simplified... |
98 |
* smk_access - determine if a subject has a specific access to an object |
21c7eae21 Make Smack operat... |
99 100 |
* @subject: a pointer to the subject's Smack label entry * @object: a pointer to the object's Smack label entry |
e114e4737 Smack: Simplified... |
101 |
* @request: the access requested, in "MAY" format |
ecfcc53fe smack: implement ... |
102 |
* @a : a pointer to the audit data |
e114e4737 Smack: Simplified... |
103 104 105 106 107 |
* * This function looks up the subject/object pair in the * access rule list and returns 0 if the access is permitted, * non zero otherwise. * |
272cd7a8c Smack: Rule list ... |
108 |
* Smack labels are shared on smack_list |
e114e4737 Smack: Simplified... |
109 |
*/ |
21c7eae21 Make Smack operat... |
110 111 |
int smk_access(struct smack_known *subject, struct smack_known *object, int request, struct smk_audit_info *a) |
e114e4737 Smack: Simplified... |
112 |
{ |
7898e1f8e Subject: [PATCH] ... |
113 |
int may = MAY_NOT; |
ecfcc53fe smack: implement ... |
114 |
int rc = 0; |
e114e4737 Smack: Simplified... |
115 116 117 |
/* * Hardcoded comparisons. |
bf4b2fee9 Smack: Allow an u... |
118 119 |
*/ /* |
e114e4737 Smack: Simplified... |
120 121 |
* A star subject can't access any object. */ |
21c7eae21 Make Smack operat... |
122 |
if (subject == &smack_known_star) { |
ecfcc53fe smack: implement ... |
123 124 125 |
rc = -EACCES; goto out_audit; } |
e114e4737 Smack: Simplified... |
126 |
/* |
6d3dc07cb smack: Add suppor... |
127 128 129 130 |
* An internet object can be accessed by any subject. * Tasks cannot be assigned the internet label. * An internet subject can access any object. */ |
6c892df26 Smack: Lock mode ... |
131 |
if (object == &smack_known_web || subject == &smack_known_web) |
ecfcc53fe smack: implement ... |
132 |
goto out_audit; |
6d3dc07cb smack: Add suppor... |
133 |
/* |
e114e4737 Smack: Simplified... |
134 135 |
* A star object can be accessed by any subject. */ |
21c7eae21 Make Smack operat... |
136 |
if (object == &smack_known_star) |
ecfcc53fe smack: implement ... |
137 |
goto out_audit; |
e114e4737 Smack: Simplified... |
138 139 140 141 |
/* * An object can be accessed in any way by a subject * with the same label. */ |
21c7eae21 Make Smack operat... |
142 |
if (subject->smk_known == object->smk_known) |
ecfcc53fe smack: implement ... |
143 |
goto out_audit; |
e114e4737 Smack: Simplified... |
144 |
/* |
6c892df26 Smack: Lock mode ... |
145 146 |
* A hat subject can read or lock any object. * A floor object can be read or locked by any subject. |
e114e4737 Smack: Simplified... |
147 |
*/ |
6c892df26 Smack: Lock mode ... |
148 149 |
if ((request & MAY_ANYREAD) == request || (request & MAY_LOCK) == request) { |
21c7eae21 Make Smack operat... |
150 |
if (object == &smack_known_floor) |
ecfcc53fe smack: implement ... |
151 |
goto out_audit; |
21c7eae21 Make Smack operat... |
152 |
if (subject == &smack_known_hat) |
ecfcc53fe smack: implement ... |
153 |
goto out_audit; |
e114e4737 Smack: Simplified... |
154 155 156 157 158 |
} /* * Beyond here an explicit relationship is required. * If the requested access is contained in the available * access (e.g. read is included in readwrite) it's |
7898e1f8e Subject: [PATCH] ... |
159 160 |
* good. A negative response from smk_access_entry() * indicates there is no entry for this pair. |
e114e4737 Smack: Simplified... |
161 |
*/ |
7898e1f8e Subject: [PATCH] ... |
162 |
rcu_read_lock(); |
21c7eae21 Make Smack operat... |
163 164 |
may = smk_access_entry(subject->smk_known, object->smk_known, &subject->smk_rules); |
7898e1f8e Subject: [PATCH] ... |
165 |
rcu_read_unlock(); |
d166c8024 Smack: Bring-up a... |
166 167 |
if (may <= 0 || (request & may) != request) { rc = -EACCES; |
ecfcc53fe smack: implement ... |
168 |
goto out_audit; |
d166c8024 Smack: Bring-up a... |
169 170 171 172 173 174 175 176 |
} #ifdef CONFIG_SECURITY_SMACK_BRINGUP /* * Return a positive value if using bringup mode. * This allows the hooks to identify checks that * succeed because of "b" rules. */ if (may & MAY_BRINGUP) |
bf4b2fee9 Smack: Allow an u... |
177 |
rc = SMACK_BRINGUP_ALLOW; |
d166c8024 Smack: Bring-up a... |
178 |
#endif |
e114e4737 Smack: Simplified... |
179 |
|
ecfcc53fe smack: implement ... |
180 |
out_audit: |
bf4b2fee9 Smack: Allow an u... |
181 182 183 184 185 186 187 188 189 |
#ifdef CONFIG_SECURITY_SMACK_BRINGUP if (rc < 0) { if (object == smack_unconfined) rc = SMACK_UNCONFINED_OBJECT; if (subject == smack_unconfined) rc = SMACK_UNCONFINED_SUBJECT; } #endif |
ecfcc53fe smack: implement ... |
190 191 |
#ifdef CONFIG_AUDIT if (a) |
21c7eae21 Make Smack operat... |
192 193 |
smack_log(subject->smk_known, object->smk_known, request, rc, a); |
ecfcc53fe smack: implement ... |
194 |
#endif |
d166c8024 Smack: Bring-up a... |
195 |
|
ecfcc53fe smack: implement ... |
196 |
return rc; |
e114e4737 Smack: Simplified... |
197 198 199 |
} /** |
959e6c7f1 Smack: fix the su... |
200 |
* smk_tskacc - determine if a task has a specific access to an object |
21c7eae21 Make Smack operat... |
201 202 |
* @tsp: a pointer to the subject's task * @obj_known: a pointer to the object's label entry |
251a2a958 smack: fix lots o... |
203 |
* @mode: the access requested, in "MAY" format |
ecfcc53fe smack: implement ... |
204 |
* @a : common audit data |
e114e4737 Smack: Simplified... |
205 |
* |
959e6c7f1 Smack: fix the su... |
206 |
* This function checks the subject task's label/object label pair |
e114e4737 Smack: Simplified... |
207 |
* in the access rule list and returns 0 if the access is permitted, |
959e6c7f1 Smack: fix the su... |
208 |
* non zero otherwise. It allows that the task may have the capability |
e114e4737 Smack: Simplified... |
209 210 |
* to override the rules. */ |
21c7eae21 Make Smack operat... |
211 |
int smk_tskacc(struct task_smack *tsp, struct smack_known *obj_known, |
959e6c7f1 Smack: fix the su... |
212 |
u32 mode, struct smk_audit_info *a) |
e114e4737 Smack: Simplified... |
213 |
{ |
21c7eae21 Make Smack operat... |
214 |
struct smack_known *sbj_known = smk_of_task(tsp); |
7898e1f8e Subject: [PATCH] ... |
215 |
int may; |
e114e4737 Smack: Simplified... |
216 |
int rc; |
7898e1f8e Subject: [PATCH] ... |
217 218 219 |
/* * Check the global rule list */ |
21c7eae21 Make Smack operat... |
220 |
rc = smk_access(sbj_known, obj_known, mode, NULL); |
d166c8024 Smack: Bring-up a... |
221 |
if (rc >= 0) { |
7898e1f8e Subject: [PATCH] ... |
222 223 224 225 |
/* * If there is an entry in the task's rule list * it can further restrict access. */ |
21c7eae21 Make Smack operat... |
226 227 228 |
may = smk_access_entry(sbj_known->smk_known, obj_known->smk_known, &tsp->smk_rules); |
7898e1f8e Subject: [PATCH] ... |
229 230 231 232 233 234 |
if (may < 0) goto out_audit; if ((mode & may) == mode) goto out_audit; rc = -EACCES; } |
e114e4737 Smack: Simplified... |
235 |
|
154462353 smack: limit priv... |
236 |
/* |
1880eff77 Smack: onlycap li... |
237 |
* Allow for priviliged to override policy. |
154462353 smack: limit priv... |
238 |
*/ |
1880eff77 Smack: onlycap li... |
239 |
if (rc != 0 && smack_privileged(CAP_MAC_OVERRIDE)) |
7898e1f8e Subject: [PATCH] ... |
240 |
rc = 0; |
e114e4737 Smack: Simplified... |
241 |
|
ecfcc53fe smack: implement ... |
242 243 244 |
out_audit: #ifdef CONFIG_AUDIT if (a) |
21c7eae21 Make Smack operat... |
245 246 |
smack_log(sbj_known->smk_known, obj_known->smk_known, mode, rc, a); |
ecfcc53fe smack: implement ... |
247 |
#endif |
e114e4737 Smack: Simplified... |
248 249 |
return rc; } |
959e6c7f1 Smack: fix the su... |
250 251 |
/** * smk_curacc - determine if current has a specific access to an object |
21c7eae21 Make Smack operat... |
252 |
* @obj_known: a pointer to the object's Smack label entry |
959e6c7f1 Smack: fix the su... |
253 254 255 256 257 258 259 260 |
* @mode: the access requested, in "MAY" format * @a : common audit data * * This function checks the current subject label/object label pair * in the access rule list and returns 0 if the access is permitted, * non zero otherwise. It allows that current may have the capability * to override the rules. */ |
21c7eae21 Make Smack operat... |
261 262 |
int smk_curacc(struct smack_known *obj_known, u32 mode, struct smk_audit_info *a) |
959e6c7f1 Smack: fix the su... |
263 |
{ |
b17103a8b Smack: Abstract u... |
264 |
struct task_smack *tsp = smack_cred(current_cred()); |
959e6c7f1 Smack: fix the su... |
265 |
|
21c7eae21 Make Smack operat... |
266 |
return smk_tskacc(tsp, obj_known, mode, a); |
959e6c7f1 Smack: fix the su... |
267 |
} |
ecfcc53fe smack: implement ... |
268 269 270 271 272 273 274 275 276 277 278 |
#ifdef CONFIG_AUDIT /** * smack_str_from_perm : helper to transalate an int to a * readable string * @string : the string to fill * @access : the int * */ static inline void smack_str_from_perm(char *string, int access) { int i = 0; |
c0ab6e56d Smack: Implement ... |
279 |
|
ecfcc53fe smack: implement ... |
280 281 282 283 284 285 286 287 |
if (access & MAY_READ) string[i++] = 'r'; if (access & MAY_WRITE) string[i++] = 'w'; if (access & MAY_EXEC) string[i++] = 'x'; if (access & MAY_APPEND) string[i++] = 'a'; |
a87d79ad7 Smack: add missin... |
288 289 |
if (access & MAY_TRANSMUTE) string[i++] = 't'; |
c0ab6e56d Smack: Implement ... |
290 291 |
if (access & MAY_LOCK) string[i++] = 'l'; |
ecfcc53fe smack: implement ... |
292 293 294 295 296 297 298 299 300 301 302 303 |
string[i] = '\0'; } /** * smack_log_callback - SMACK specific information * will be called by generic audit code * @ab : the audit_buffer * @a : audit_data * */ static void smack_log_callback(struct audit_buffer *ab, void *a) { struct common_audit_data *ad = a; |
3b3b0e4fc LSM: shrink sizeo... |
304 |
struct smack_audit_data *sad = ad->smack_audit_data; |
ed5215a21 Move variable fun... |
305 |
audit_log_format(ab, "lsm=SMACK fn=%s action=%s", |
3b3b0e4fc LSM: shrink sizeo... |
306 |
ad->smack_audit_data->function, |
ecfcc53fe smack: implement ... |
307 308 309 310 311 |
sad->result ? "denied" : "granted"); audit_log_format(ab, " subject="); audit_log_untrustedstring(ab, sad->subject); audit_log_format(ab, " object="); audit_log_untrustedstring(ab, sad->object); |
668678185 Smack: adds smack... |
312 313 314 315 |
if (sad->request[0] == '\0') audit_log_format(ab, " labels_differ"); else audit_log_format(ab, " requested=%s", sad->request); |
ecfcc53fe smack: implement ... |
316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 |
} /** * smack_log - Audit the granting or denial of permissions. * @subject_label : smack label of the requester * @object_label : smack label of the object being accessed * @request: requested permissions * @result: result from smk_access * @a: auxiliary audit data * * Audit the granting or denial of permissions in accordance * with the policy. */ void smack_log(char *subject_label, char *object_label, int request, int result, struct smk_audit_info *ad) { |
bf4b2fee9 Smack: Allow an u... |
332 333 334 |
#ifdef CONFIG_SECURITY_SMACK_BRINGUP char request_buffer[SMK_NUM_ACCESS_TYPE + 5]; #else |
ecfcc53fe smack: implement ... |
335 |
char request_buffer[SMK_NUM_ACCESS_TYPE + 1]; |
bf4b2fee9 Smack: Allow an u... |
336 |
#endif |
ecfcc53fe smack: implement ... |
337 338 339 340 |
struct smack_audit_data *sad; struct common_audit_data *a = &ad->a; /* check if we have to log the current event */ |
bf4b2fee9 Smack: Allow an u... |
341 |
if (result < 0 && (log_policy & SMACK_AUDIT_DENIED) == 0) |
ecfcc53fe smack: implement ... |
342 343 344 |
return; if (result == 0 && (log_policy & SMACK_AUDIT_ACCEPT) == 0) return; |
3b3b0e4fc LSM: shrink sizeo... |
345 346 347 348 |
sad = a->smack_audit_data; if (sad->function == NULL) sad->function = "unknown"; |
ecfcc53fe smack: implement ... |
349 350 |
/* end preparing the audit data */ |
ecfcc53fe smack: implement ... |
351 352 353 |
smack_str_from_perm(request_buffer, request); sad->subject = subject_label; sad->object = object_label; |
bf4b2fee9 Smack: Allow an u... |
354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 |
#ifdef CONFIG_SECURITY_SMACK_BRINGUP /* * The result may be positive in bringup mode. * A positive result is an allow, but not for normal reasons. * Mark it as successful, but don't filter it out even if * the logging policy says to do so. */ if (result == SMACK_UNCONFINED_SUBJECT) strcat(request_buffer, "(US)"); else if (result == SMACK_UNCONFINED_OBJECT) strcat(request_buffer, "(UO)"); if (result > 0) result = 0; #endif |
ecfcc53fe smack: implement ... |
369 370 |
sad->request = request_buffer; sad->result = result; |
ecfcc53fe smack: implement ... |
371 |
|
b61c37f57 lsm_audit: don't ... |
372 |
common_lsm_audit(a, smack_log_callback, NULL); |
ecfcc53fe smack: implement ... |
373 374 375 376 377 378 379 |
} #else /* #ifdef CONFIG_AUDIT */ void smack_log(char *subject_label, char *object_label, int request, int result, struct smk_audit_info *ad) { } #endif |
f7112e6c9 Smack: allow for ... |
380 |
DEFINE_MUTEX(smack_known_lock); |
e114e4737 Smack: Simplified... |
381 |
|
4d7cf4a1f security: smack: ... |
382 383 384 385 386 387 388 389 390 391 392 |
struct hlist_head smack_known_hash[SMACK_HASH_SLOTS]; /** * smk_insert_entry - insert a smack label into a hash map, * * this function must be called under smack_known_lock */ void smk_insert_entry(struct smack_known *skp) { unsigned int hash; struct hlist_head *head; |
8387ff257 vfs: make the str... |
393 |
hash = full_name_hash(NULL, skp->smk_known, strlen(skp->smk_known)); |
4d7cf4a1f security: smack: ... |
394 395 396 397 398 |
head = &smack_known_hash[hash & (SMACK_HASH_SLOTS - 1)]; hlist_add_head_rcu(&skp->smk_hashed, head); list_add_rcu(&skp->list, &smack_known_list); } |
e114e4737 Smack: Simplified... |
399 |
/** |
272cd7a8c Smack: Rule list ... |
400 401 402 403 |
* smk_find_entry - find a label on the list, return the list entry * @string: a text string that might be a Smack label * * Returns a pointer to the entry in the label list that |
e774ad683 smack: pass error... |
404 |
* matches the passed string or NULL if not found. |
272cd7a8c Smack: Rule list ... |
405 406 407 |
*/ struct smack_known *smk_find_entry(const char *string) { |
4d7cf4a1f security: smack: ... |
408 409 |
unsigned int hash; struct hlist_head *head; |
272cd7a8c Smack: Rule list ... |
410 |
struct smack_known *skp; |
8387ff257 vfs: make the str... |
411 |
hash = full_name_hash(NULL, string, strlen(string)); |
4d7cf4a1f security: smack: ... |
412 413 414 |
head = &smack_known_hash[hash & (SMACK_HASH_SLOTS - 1)]; hlist_for_each_entry_rcu(skp, head, smk_hashed) |
f7112e6c9 Smack: allow for ... |
415 |
if (strcmp(skp->smk_known, string) == 0) |
272cd7a8c Smack: Rule list ... |
416 |
return skp; |
272cd7a8c Smack: Rule list ... |
417 418 419 420 421 |
return NULL; } /** |
0e94ae17c Smack: allow to a... |
422 423 |
* smk_parse_smack - parse smack label from a text string * @string: a text string that might contain a Smack label |
e114e4737 Smack: Simplified... |
424 |
* @len: the maximum size, or zero if it is NULL terminated. |
f7112e6c9 Smack: allow for ... |
425 |
* |
e774ad683 smack: pass error... |
426 |
* Returns a pointer to the clean label or an error code. |
e114e4737 Smack: Simplified... |
427 |
*/ |
f7112e6c9 Smack: allow for ... |
428 |
char *smk_parse_smack(const char *string, int len) |
e114e4737 Smack: Simplified... |
429 |
{ |
f7112e6c9 Smack: allow for ... |
430 |
char *smack; |
e114e4737 Smack: Simplified... |
431 |
int i; |
f7112e6c9 Smack: allow for ... |
432 433 434 435 436 437 438 439 440 |
if (len <= 0) len = strlen(string) + 1; /* * Reserve a leading '-' as an indicator that * this isn't a label, but an option to interfaces * including /smack/cipso and /smack/cipso2 */ if (string[0] == '-') |
e774ad683 smack: pass error... |
441 |
return ERR_PTR(-EINVAL); |
f7112e6c9 Smack: allow for ... |
442 443 444 445 446 447 448 |
for (i = 0; i < len; i++) if (string[i] > '~' || string[i] <= ' ' || string[i] == '/' || string[i] == '"' || string[i] == '\\' || string[i] == '\'') break; if (i == 0 || i >= SMK_LONGLABEL) |
e774ad683 smack: pass error... |
449 |
return ERR_PTR(-EINVAL); |
f7112e6c9 Smack: allow for ... |
450 |
|
e5bfad3d7 smack: use GFP_NO... |
451 |
smack = kzalloc(i + 1, GFP_NOFS); |
e774ad683 smack: pass error... |
452 453 454 455 |
if (smack == NULL) return ERR_PTR(-ENOMEM); strncpy(smack, string, i); |
5c1b66240 security: smack: ... |
456 |
|
f7112e6c9 Smack: allow for ... |
457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 |
return smack; } /** * smk_netlbl_mls - convert a catset to netlabel mls categories * @catset: the Smack categories * @sap: where to put the netlabel categories * * Allocates and fills attr.mls * Returns 0 on success, error code on failure. */ int smk_netlbl_mls(int level, char *catset, struct netlbl_lsm_secattr *sap, int len) { unsigned char *cp; unsigned char m; int cat; int rc; int byte; sap->flags |= NETLBL_SECATTR_MLS_CAT; sap->attr.mls.lvl = level; |
4b8feff25 netlabel: fix the... |
479 |
sap->attr.mls.cat = NULL; |
f7112e6c9 Smack: allow for ... |
480 481 482 483 484 |
for (cat = 1, cp = catset, byte = 0; byte < len; cp++, byte++) for (m = 0x80; m != 0; m >>= 1, cat++) { if ((m & *cp) == 0) continue; |
4fbe63d1c netlabel: shorter... |
485 |
rc = netlbl_catmap_setbit(&sap->attr.mls.cat, |
e5bfad3d7 smack: use GFP_NO... |
486 |
cat, GFP_NOFS); |
f7112e6c9 Smack: allow for ... |
487 |
if (rc < 0) { |
4fbe63d1c netlabel: shorter... |
488 |
netlbl_catmap_free(sap->attr.mls.cat); |
f7112e6c9 Smack: allow for ... |
489 490 491 492 493 |
return rc; } } return 0; |
0e94ae17c Smack: allow to a... |
494 495 496 |
} /** |
322dd63c7 Smack: Use the ne... |
497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 |
* smack_populate_secattr - fill in the smack_known netlabel information * @skp: pointer to the structure to fill * * Populate the netlabel secattr structure for a Smack label. * * Returns 0 unless creating the category mapping fails */ int smack_populate_secattr(struct smack_known *skp) { int slen; skp->smk_netlabel.attr.secid = skp->smk_secid; skp->smk_netlabel.domain = skp->smk_known; skp->smk_netlabel.cache = netlbl_secattr_cache_alloc(GFP_ATOMIC); if (skp->smk_netlabel.cache != NULL) { skp->smk_netlabel.flags |= NETLBL_SECATTR_CACHE; skp->smk_netlabel.cache->free = NULL; skp->smk_netlabel.cache->data = skp; } skp->smk_netlabel.flags |= NETLBL_SECATTR_SECID | NETLBL_SECATTR_MLS_LVL | NETLBL_SECATTR_DOMAIN; /* * If direct labeling works use it. * Otherwise use mapped labeling. */ slen = strlen(skp->smk_known); if (slen < SMK_CIPSOLEN) return smk_netlbl_mls(smack_cipso_direct, skp->smk_known, &skp->smk_netlabel, slen); return smk_netlbl_mls(smack_cipso_mapped, (char *)&skp->smk_secid, &skp->smk_netlabel, sizeof(skp->smk_secid)); } /** |
0e94ae17c Smack: allow to a... |
533 534 535 536 537 |
* smk_import_entry - import a label, return the list entry * @string: a text string that might be a Smack label * @len: the maximum size, or zero if it is NULL terminated. * * Returns a pointer to the entry in the label list that |
e774ad683 smack: pass error... |
538 539 |
* matches the passed string, adding it if necessary, * or an error code. |
0e94ae17c Smack: allow to a... |
540 541 542 543 |
*/ struct smack_known *smk_import_entry(const char *string, int len) { struct smack_known *skp; |
f7112e6c9 Smack: allow for ... |
544 |
char *smack; |
f7112e6c9 Smack: allow for ... |
545 |
int rc; |
e114e4737 Smack: Simplified... |
546 |
|
f7112e6c9 Smack: allow for ... |
547 |
smack = smk_parse_smack(string, len); |
e774ad683 smack: pass error... |
548 549 |
if (IS_ERR(smack)) return ERR_CAST(smack); |
e114e4737 Smack: Simplified... |
550 551 |
mutex_lock(&smack_known_lock); |
272cd7a8c Smack: Rule list ... |
552 |
skp = smk_find_entry(smack); |
f7112e6c9 Smack: allow for ... |
553 554 |
if (skp != NULL) goto freeout; |
e114e4737 Smack: Simplified... |
555 |
|
e5bfad3d7 smack: use GFP_NO... |
556 |
skp = kzalloc(sizeof(*skp), GFP_NOFS); |
e774ad683 smack: pass error... |
557 558 |
if (skp == NULL) { skp = ERR_PTR(-ENOMEM); |
f7112e6c9 Smack: allow for ... |
559 |
goto freeout; |
e774ad683 smack: pass error... |
560 |
} |
e114e4737 Smack: Simplified... |
561 |
|
f7112e6c9 Smack: allow for ... |
562 563 |
skp->smk_known = smack; skp->smk_secid = smack_next_secid++; |
f7112e6c9 Smack: allow for ... |
564 |
|
322dd63c7 Smack: Use the ne... |
565 |
rc = smack_populate_secattr(skp); |
f7112e6c9 Smack: allow for ... |
566 567 568 569 570 571 572 |
if (rc >= 0) { INIT_LIST_HEAD(&skp->smk_rules); mutex_init(&skp->smk_rules_lock); /* * Make sure that the entry is actually * filled before putting it on the list. */ |
4d7cf4a1f security: smack: ... |
573 |
smk_insert_entry(skp); |
f7112e6c9 Smack: allow for ... |
574 575 |
goto unlockout; } |
f7112e6c9 Smack: allow for ... |
576 |
kfree(skp); |
e774ad683 smack: pass error... |
577 |
skp = ERR_PTR(rc); |
f7112e6c9 Smack: allow for ... |
578 579 580 |
freeout: kfree(smack); unlockout: |
e114e4737 Smack: Simplified... |
581 582 583 584 585 586 |
mutex_unlock(&smack_known_lock); return skp; } /** |
e114e4737 Smack: Simplified... |
587 588 589 |
* smack_from_secid - find the Smack label associated with a secid * @secid: an integer that might be associated with a Smack label * |
2f823ff8b Smack: Improve ac... |
590 |
* Returns a pointer to the appropriate Smack label entry if there is one, |
e114e4737 Smack: Simplified... |
591 592 |
* otherwise a pointer to the invalid Smack label. */ |
2f823ff8b Smack: Improve ac... |
593 |
struct smack_known *smack_from_secid(const u32 secid) |
e114e4737 Smack: Simplified... |
594 595 |
{ struct smack_known *skp; |
7198e2eeb smack: convert sm... |
596 597 598 599 |
rcu_read_lock(); list_for_each_entry_rcu(skp, &smack_known_list, list) { if (skp->smk_secid == secid) { rcu_read_unlock(); |
2f823ff8b Smack: Improve ac... |
600 |
return skp; |
7198e2eeb smack: convert sm... |
601 602 |
} } |
e114e4737 Smack: Simplified... |
603 604 605 606 607 |
/* * If we got this far someone asked for the translation * of a secid that is not on the list. */ |
7198e2eeb smack: convert sm... |
608 |
rcu_read_unlock(); |
152f91d4d Smack: Remove unn... |
609 |
return &smack_known_huh; |
e114e4737 Smack: Simplified... |
610 |
} |
c0d77c884 Smack: allow mult... |
611 612 613 614 615 616 617 618 619 620 |
/* * Unless a process is running with one of these labels * even having CAP_MAC_OVERRIDE isn't enough to grant * privilege to violate MAC policy. If no labels are * designated (the empty list case) capabilities apply to * everyone. */ LIST_HEAD(smack_onlycap_list); DEFINE_MUTEX(smack_onlycap_lock); |
d19dfe58b Smack: Privilege ... |
621 622 623 624 625 |
/** * smack_privileged_cred - are all privilege requirements met by cred * @cap: The requested capability * @cred: the credential to use * |
c0d77c884 Smack: allow mult... |
626 627 628 |
* Is the task privileged and allowed to be privileged * by the onlycap rule. * |
f28e783ff Smack: Use cap_ca... |
629 |
* Returns true if the task is allowed to be privileged, false if it's not. |
c0d77c884 Smack: allow mult... |
630 |
*/ |
d19dfe58b Smack: Privilege ... |
631 |
bool smack_privileged_cred(int cap, const struct cred *cred) |
c0d77c884 Smack: allow mult... |
632 |
{ |
b17103a8b Smack: Abstract u... |
633 |
struct task_smack *tsp = smack_cred(cred); |
d19dfe58b Smack: Privilege ... |
634 |
struct smack_known *skp = tsp->smk_task; |
38416e539 Smack: limited ca... |
635 |
struct smack_known_list_elem *sklep; |
f28e783ff Smack: Use cap_ca... |
636 |
int rc; |
c0d77c884 Smack: allow mult... |
637 |
|
c1a85a00e LSM: generalize f... |
638 |
rc = cap_capable(cred, &init_user_ns, cap, CAP_OPT_NONE); |
f28e783ff Smack: Use cap_ca... |
639 640 |
if (rc) return false; |
c0d77c884 Smack: allow mult... |
641 642 643 644 |
rcu_read_lock(); if (list_empty(&smack_onlycap_list)) { rcu_read_unlock(); |
f28e783ff Smack: Use cap_ca... |
645 |
return true; |
c0d77c884 Smack: allow mult... |
646 |
} |
38416e539 Smack: limited ca... |
647 648 |
list_for_each_entry_rcu(sklep, &smack_onlycap_list, list) { if (sklep->smk_label == skp) { |
c0d77c884 Smack: allow mult... |
649 |
rcu_read_unlock(); |
f28e783ff Smack: Use cap_ca... |
650 |
return true; |
c0d77c884 Smack: allow mult... |
651 652 653 |
} } rcu_read_unlock(); |
f28e783ff Smack: Use cap_ca... |
654 |
return false; |
c0d77c884 Smack: allow mult... |
655 |
} |
d19dfe58b Smack: Privilege ... |
656 657 658 659 660 661 662 663 664 665 666 667 668 |
/** * smack_privileged - are all privilege requirements met * @cap: The requested capability * * Is the task privileged and allowed to be privileged * by the onlycap rule. * * Returns true if the task is allowed to be privileged, false if it's not. */ bool smack_privileged(int cap) { /* |
8f939abd8 Smack: Handle io_... |
669 670 |
* Kernel threads may not have credentials we can use. * The io_uring kernel threads do have reliable credentials. |
d19dfe58b Smack: Privilege ... |
671 |
*/ |
8f939abd8 Smack: Handle io_... |
672 |
if ((current->flags & (PF_KTHREAD | PF_IO_WORKER)) == PF_KTHREAD) |
d19dfe58b Smack: Privilege ... |
673 674 675 676 |
return true; return smack_privileged_cred(cap, current_cred()); } |