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Commit | Line | Data |
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973c9f4f | 1 | /* Userspace key control operations |
1da177e4 | 2 | * |
3e30148c | 3 | * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved. |
1da177e4 LT |
4 | * Written by David Howells (dhowells@redhat.com) |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #include <linux/module.h> | |
13 | #include <linux/init.h> | |
14 | #include <linux/sched.h> | |
29930025 | 15 | #include <linux/sched/task.h> |
1da177e4 LT |
16 | #include <linux/slab.h> |
17 | #include <linux/syscalls.h> | |
59e6b9c1 | 18 | #include <linux/key.h> |
1da177e4 LT |
19 | #include <linux/keyctl.h> |
20 | #include <linux/fs.h> | |
c59ede7b | 21 | #include <linux/capability.h> |
5b825c3a | 22 | #include <linux/cred.h> |
0cb409d9 | 23 | #include <linux/string.h> |
1da177e4 | 24 | #include <linux/err.h> |
38bbca6b | 25 | #include <linux/vmalloc.h> |
70a5bb72 | 26 | #include <linux/security.h> |
a27bb332 | 27 | #include <linux/uio.h> |
7c0f6ba6 | 28 | #include <linux/uaccess.h> |
1da177e4 LT |
29 | #include "internal.h" |
30 | ||
aa9d4437 DH |
31 | #define KEY_MAX_DESC_SIZE 4096 |
32 | ||
0cb409d9 DA |
33 | static int key_get_type_from_user(char *type, |
34 | const char __user *_type, | |
35 | unsigned len) | |
36 | { | |
37 | int ret; | |
38 | ||
39 | ret = strncpy_from_user(type, _type, len); | |
0cb409d9 | 40 | if (ret < 0) |
4303ef19 | 41 | return ret; |
0cb409d9 DA |
42 | if (ret == 0 || ret >= len) |
43 | return -EINVAL; | |
54e2c2c1 DH |
44 | if (type[0] == '.') |
45 | return -EPERM; | |
0cb409d9 | 46 | type[len - 1] = '\0'; |
0cb409d9 DA |
47 | return 0; |
48 | } | |
49 | ||
1da177e4 | 50 | /* |
973c9f4f DH |
51 | * Extract the description of a new key from userspace and either add it as a |
52 | * new key to the specified keyring or update a matching key in that keyring. | |
53 | * | |
cf7f601c DH |
54 | * If the description is NULL or an empty string, the key type is asked to |
55 | * generate one from the payload. | |
56 | * | |
973c9f4f DH |
57 | * The keyring must be writable so that we can attach the key to it. |
58 | * | |
59 | * If successful, the new key's serial number is returned, otherwise an error | |
60 | * code is returned. | |
1da177e4 | 61 | */ |
1e7bfb21 HC |
62 | SYSCALL_DEFINE5(add_key, const char __user *, _type, |
63 | const char __user *, _description, | |
64 | const void __user *, _payload, | |
65 | size_t, plen, | |
66 | key_serial_t, ringid) | |
1da177e4 | 67 | { |
664cceb0 | 68 | key_ref_t keyring_ref, key_ref; |
1da177e4 LT |
69 | char type[32], *description; |
70 | void *payload; | |
0cb409d9 | 71 | long ret; |
1da177e4 LT |
72 | |
73 | ret = -EINVAL; | |
38bbca6b | 74 | if (plen > 1024 * 1024 - 1) |
1da177e4 LT |
75 | goto error; |
76 | ||
77 | /* draw all the data into kernel space */ | |
0cb409d9 | 78 | ret = key_get_type_from_user(type, _type, sizeof(type)); |
1da177e4 LT |
79 | if (ret < 0) |
80 | goto error; | |
1da177e4 | 81 | |
cf7f601c DH |
82 | description = NULL; |
83 | if (_description) { | |
aa9d4437 | 84 | description = strndup_user(_description, KEY_MAX_DESC_SIZE); |
cf7f601c DH |
85 | if (IS_ERR(description)) { |
86 | ret = PTR_ERR(description); | |
87 | goto error; | |
88 | } | |
89 | if (!*description) { | |
90 | kfree(description); | |
91 | description = NULL; | |
a4e3b8d7 MZ |
92 | } else if ((description[0] == '.') && |
93 | (strncmp(type, "keyring", 7) == 0)) { | |
94 | ret = -EPERM; | |
95 | goto error2; | |
cf7f601c | 96 | } |
0cb409d9 | 97 | } |
1da177e4 LT |
98 | |
99 | /* pull the payload in if one was supplied */ | |
100 | payload = NULL; | |
101 | ||
102 | if (_payload) { | |
103 | ret = -ENOMEM; | |
752ade68 MH |
104 | payload = kvmalloc(plen, GFP_KERNEL); |
105 | if (!payload) | |
106 | goto error2; | |
1da177e4 LT |
107 | |
108 | ret = -EFAULT; | |
109 | if (copy_from_user(payload, _payload, plen) != 0) | |
110 | goto error3; | |
111 | } | |
112 | ||
113 | /* find the target keyring (which must be writable) */ | |
f5895943 | 114 | keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE); |
664cceb0 DH |
115 | if (IS_ERR(keyring_ref)) { |
116 | ret = PTR_ERR(keyring_ref); | |
1da177e4 LT |
117 | goto error3; |
118 | } | |
119 | ||
120 | /* create or update the requested key and add it to the target | |
121 | * keyring */ | |
664cceb0 | 122 | key_ref = key_create_or_update(keyring_ref, type, description, |
6b79ccb5 AR |
123 | payload, plen, KEY_PERM_UNDEF, |
124 | KEY_ALLOC_IN_QUOTA); | |
664cceb0 DH |
125 | if (!IS_ERR(key_ref)) { |
126 | ret = key_ref_to_ptr(key_ref)->serial; | |
127 | key_ref_put(key_ref); | |
1da177e4 LT |
128 | } |
129 | else { | |
664cceb0 | 130 | ret = PTR_ERR(key_ref); |
1da177e4 LT |
131 | } |
132 | ||
664cceb0 | 133 | key_ref_put(keyring_ref); |
1da177e4 | 134 | error3: |
d0e0eba0 | 135 | kvfree(payload); |
1da177e4 LT |
136 | error2: |
137 | kfree(description); | |
138 | error: | |
139 | return ret; | |
a8b17ed0 | 140 | } |
1da177e4 | 141 | |
1da177e4 | 142 | /* |
973c9f4f DH |
143 | * Search the process keyrings and keyring trees linked from those for a |
144 | * matching key. Keyrings must have appropriate Search permission to be | |
145 | * searched. | |
146 | * | |
147 | * If a key is found, it will be attached to the destination keyring if there's | |
148 | * one specified and the serial number of the key will be returned. | |
149 | * | |
150 | * If no key is found, /sbin/request-key will be invoked if _callout_info is | |
151 | * non-NULL in an attempt to create a key. The _callout_info string will be | |
152 | * passed to /sbin/request-key to aid with completing the request. If the | |
153 | * _callout_info string is "" then it will be changed to "-". | |
1da177e4 | 154 | */ |
1e7bfb21 HC |
155 | SYSCALL_DEFINE4(request_key, const char __user *, _type, |
156 | const char __user *, _description, | |
157 | const char __user *, _callout_info, | |
158 | key_serial_t, destringid) | |
1da177e4 LT |
159 | { |
160 | struct key_type *ktype; | |
664cceb0 DH |
161 | struct key *key; |
162 | key_ref_t dest_ref; | |
4a38e122 | 163 | size_t callout_len; |
1da177e4 | 164 | char type[32], *description, *callout_info; |
0cb409d9 | 165 | long ret; |
1da177e4 LT |
166 | |
167 | /* pull the type into kernel space */ | |
0cb409d9 | 168 | ret = key_get_type_from_user(type, _type, sizeof(type)); |
1da177e4 LT |
169 | if (ret < 0) |
170 | goto error; | |
1260f801 | 171 | |
1da177e4 | 172 | /* pull the description into kernel space */ |
aa9d4437 | 173 | description = strndup_user(_description, KEY_MAX_DESC_SIZE); |
0cb409d9 DA |
174 | if (IS_ERR(description)) { |
175 | ret = PTR_ERR(description); | |
1da177e4 | 176 | goto error; |
0cb409d9 | 177 | } |
1da177e4 LT |
178 | |
179 | /* pull the callout info into kernel space */ | |
180 | callout_info = NULL; | |
4a38e122 | 181 | callout_len = 0; |
1da177e4 | 182 | if (_callout_info) { |
0cb409d9 DA |
183 | callout_info = strndup_user(_callout_info, PAGE_SIZE); |
184 | if (IS_ERR(callout_info)) { | |
185 | ret = PTR_ERR(callout_info); | |
1da177e4 | 186 | goto error2; |
0cb409d9 | 187 | } |
4a38e122 | 188 | callout_len = strlen(callout_info); |
1da177e4 LT |
189 | } |
190 | ||
191 | /* get the destination keyring if specified */ | |
664cceb0 | 192 | dest_ref = NULL; |
1da177e4 | 193 | if (destringid) { |
5593122e | 194 | dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE, |
f5895943 | 195 | KEY_NEED_WRITE); |
664cceb0 DH |
196 | if (IS_ERR(dest_ref)) { |
197 | ret = PTR_ERR(dest_ref); | |
1da177e4 LT |
198 | goto error3; |
199 | } | |
200 | } | |
201 | ||
202 | /* find the key type */ | |
203 | ktype = key_type_lookup(type); | |
204 | if (IS_ERR(ktype)) { | |
205 | ret = PTR_ERR(ktype); | |
206 | goto error4; | |
207 | } | |
208 | ||
209 | /* do the search */ | |
4a38e122 DH |
210 | key = request_key_and_link(ktype, description, callout_info, |
211 | callout_len, NULL, key_ref_to_ptr(dest_ref), | |
7e047ef5 | 212 | KEY_ALLOC_IN_QUOTA); |
1da177e4 LT |
213 | if (IS_ERR(key)) { |
214 | ret = PTR_ERR(key); | |
215 | goto error5; | |
216 | } | |
217 | ||
4aab1e89 DH |
218 | /* wait for the key to finish being constructed */ |
219 | ret = wait_for_key_construction(key, 1); | |
220 | if (ret < 0) | |
221 | goto error6; | |
222 | ||
1da177e4 LT |
223 | ret = key->serial; |
224 | ||
4aab1e89 | 225 | error6: |
3e30148c | 226 | key_put(key); |
c5b60b5e | 227 | error5: |
1da177e4 | 228 | key_type_put(ktype); |
c5b60b5e | 229 | error4: |
664cceb0 | 230 | key_ref_put(dest_ref); |
c5b60b5e | 231 | error3: |
1da177e4 | 232 | kfree(callout_info); |
c5b60b5e | 233 | error2: |
1da177e4 | 234 | kfree(description); |
c5b60b5e | 235 | error: |
1da177e4 | 236 | return ret; |
a8b17ed0 | 237 | } |
1da177e4 | 238 | |
1da177e4 | 239 | /* |
973c9f4f DH |
240 | * Get the ID of the specified process keyring. |
241 | * | |
242 | * The requested keyring must have search permission to be found. | |
243 | * | |
244 | * If successful, the ID of the requested keyring will be returned. | |
1da177e4 LT |
245 | */ |
246 | long keyctl_get_keyring_ID(key_serial_t id, int create) | |
247 | { | |
664cceb0 | 248 | key_ref_t key_ref; |
5593122e | 249 | unsigned long lflags; |
1da177e4 LT |
250 | long ret; |
251 | ||
5593122e | 252 | lflags = create ? KEY_LOOKUP_CREATE : 0; |
f5895943 | 253 | key_ref = lookup_user_key(id, lflags, KEY_NEED_SEARCH); |
664cceb0 DH |
254 | if (IS_ERR(key_ref)) { |
255 | ret = PTR_ERR(key_ref); | |
1da177e4 LT |
256 | goto error; |
257 | } | |
258 | ||
664cceb0 DH |
259 | ret = key_ref_to_ptr(key_ref)->serial; |
260 | key_ref_put(key_ref); | |
c5b60b5e | 261 | error: |
1da177e4 | 262 | return ret; |
973c9f4f | 263 | } |
1da177e4 | 264 | |
1da177e4 | 265 | /* |
973c9f4f DH |
266 | * Join a (named) session keyring. |
267 | * | |
268 | * Create and join an anonymous session keyring or join a named session | |
269 | * keyring, creating it if necessary. A named session keyring must have Search | |
270 | * permission for it to be joined. Session keyrings without this permit will | |
ee8f844e DH |
271 | * be skipped over. It is not permitted for userspace to create or join |
272 | * keyrings whose name begin with a dot. | |
973c9f4f DH |
273 | * |
274 | * If successful, the ID of the joined session keyring will be returned. | |
1da177e4 LT |
275 | */ |
276 | long keyctl_join_session_keyring(const char __user *_name) | |
277 | { | |
278 | char *name; | |
0cb409d9 | 279 | long ret; |
1da177e4 LT |
280 | |
281 | /* fetch the name from userspace */ | |
282 | name = NULL; | |
283 | if (_name) { | |
aa9d4437 | 284 | name = strndup_user(_name, KEY_MAX_DESC_SIZE); |
0cb409d9 DA |
285 | if (IS_ERR(name)) { |
286 | ret = PTR_ERR(name); | |
1da177e4 | 287 | goto error; |
0cb409d9 | 288 | } |
ee8f844e DH |
289 | |
290 | ret = -EPERM; | |
291 | if (name[0] == '.') | |
292 | goto error_name; | |
1da177e4 LT |
293 | } |
294 | ||
295 | /* join the session */ | |
296 | ret = join_session_keyring(name); | |
ee8f844e | 297 | error_name: |
0d54ee1c | 298 | kfree(name); |
c5b60b5e | 299 | error: |
1da177e4 | 300 | return ret; |
a8b17ed0 | 301 | } |
1da177e4 | 302 | |
1da177e4 | 303 | /* |
973c9f4f DH |
304 | * Update a key's data payload from the given data. |
305 | * | |
306 | * The key must grant the caller Write permission and the key type must support | |
307 | * updating for this to work. A negative key can be positively instantiated | |
308 | * with this call. | |
309 | * | |
310 | * If successful, 0 will be returned. If the key type does not support | |
311 | * updating, then -EOPNOTSUPP will be returned. | |
1da177e4 LT |
312 | */ |
313 | long keyctl_update_key(key_serial_t id, | |
314 | const void __user *_payload, | |
315 | size_t plen) | |
316 | { | |
664cceb0 | 317 | key_ref_t key_ref; |
1da177e4 LT |
318 | void *payload; |
319 | long ret; | |
320 | ||
321 | ret = -EINVAL; | |
322 | if (plen > PAGE_SIZE) | |
323 | goto error; | |
324 | ||
325 | /* pull the payload in if one was supplied */ | |
326 | payload = NULL; | |
327 | if (_payload) { | |
328 | ret = -ENOMEM; | |
329 | payload = kmalloc(plen, GFP_KERNEL); | |
330 | if (!payload) | |
331 | goto error; | |
332 | ||
333 | ret = -EFAULT; | |
334 | if (copy_from_user(payload, _payload, plen) != 0) | |
335 | goto error2; | |
336 | } | |
337 | ||
338 | /* find the target key (which must be writable) */ | |
f5895943 | 339 | key_ref = lookup_user_key(id, 0, KEY_NEED_WRITE); |
664cceb0 DH |
340 | if (IS_ERR(key_ref)) { |
341 | ret = PTR_ERR(key_ref); | |
1da177e4 LT |
342 | goto error2; |
343 | } | |
344 | ||
345 | /* update the key */ | |
664cceb0 | 346 | ret = key_update(key_ref, payload, plen); |
1da177e4 | 347 | |
664cceb0 | 348 | key_ref_put(key_ref); |
c5b60b5e | 349 | error2: |
1da177e4 | 350 | kfree(payload); |
c5b60b5e | 351 | error: |
1da177e4 | 352 | return ret; |
a8b17ed0 | 353 | } |
1da177e4 | 354 | |
1da177e4 | 355 | /* |
973c9f4f DH |
356 | * Revoke a key. |
357 | * | |
358 | * The key must be grant the caller Write or Setattr permission for this to | |
359 | * work. The key type should give up its quota claim when revoked. The key | |
360 | * and any links to the key will be automatically garbage collected after a | |
361 | * certain amount of time (/proc/sys/kernel/keys/gc_delay). | |
362 | * | |
d3600bcf MZ |
363 | * Keys with KEY_FLAG_KEEP set should not be revoked. |
364 | * | |
973c9f4f | 365 | * If successful, 0 is returned. |
1da177e4 LT |
366 | */ |
367 | long keyctl_revoke_key(key_serial_t id) | |
368 | { | |
664cceb0 | 369 | key_ref_t key_ref; |
d3600bcf | 370 | struct key *key; |
1da177e4 LT |
371 | long ret; |
372 | ||
f5895943 | 373 | key_ref = lookup_user_key(id, 0, KEY_NEED_WRITE); |
664cceb0 DH |
374 | if (IS_ERR(key_ref)) { |
375 | ret = PTR_ERR(key_ref); | |
0c2c9a3f DH |
376 | if (ret != -EACCES) |
377 | goto error; | |
f5895943 | 378 | key_ref = lookup_user_key(id, 0, KEY_NEED_SETATTR); |
0c2c9a3f DH |
379 | if (IS_ERR(key_ref)) { |
380 | ret = PTR_ERR(key_ref); | |
381 | goto error; | |
382 | } | |
1da177e4 LT |
383 | } |
384 | ||
d3600bcf | 385 | key = key_ref_to_ptr(key_ref); |
1da177e4 | 386 | ret = 0; |
d3600bcf | 387 | if (test_bit(KEY_FLAG_KEEP, &key->flags)) |
1d6d167c MZ |
388 | ret = -EPERM; |
389 | else | |
d3600bcf | 390 | key_revoke(key); |
1da177e4 | 391 | |
664cceb0 | 392 | key_ref_put(key_ref); |
c5b60b5e | 393 | error: |
1260f801 | 394 | return ret; |
a8b17ed0 | 395 | } |
1da177e4 | 396 | |
fd75815f DH |
397 | /* |
398 | * Invalidate a key. | |
399 | * | |
400 | * The key must be grant the caller Invalidate permission for this to work. | |
401 | * The key and any links to the key will be automatically garbage collected | |
402 | * immediately. | |
403 | * | |
d3600bcf MZ |
404 | * Keys with KEY_FLAG_KEEP set should not be invalidated. |
405 | * | |
fd75815f DH |
406 | * If successful, 0 is returned. |
407 | */ | |
408 | long keyctl_invalidate_key(key_serial_t id) | |
409 | { | |
410 | key_ref_t key_ref; | |
d3600bcf | 411 | struct key *key; |
fd75815f DH |
412 | long ret; |
413 | ||
414 | kenter("%d", id); | |
415 | ||
f5895943 | 416 | key_ref = lookup_user_key(id, 0, KEY_NEED_SEARCH); |
fd75815f DH |
417 | if (IS_ERR(key_ref)) { |
418 | ret = PTR_ERR(key_ref); | |
0c7774ab DH |
419 | |
420 | /* Root is permitted to invalidate certain special keys */ | |
421 | if (capable(CAP_SYS_ADMIN)) { | |
422 | key_ref = lookup_user_key(id, 0, 0); | |
423 | if (IS_ERR(key_ref)) | |
424 | goto error; | |
425 | if (test_bit(KEY_FLAG_ROOT_CAN_INVAL, | |
426 | &key_ref_to_ptr(key_ref)->flags)) | |
427 | goto invalidate; | |
428 | goto error_put; | |
429 | } | |
430 | ||
fd75815f DH |
431 | goto error; |
432 | } | |
433 | ||
0c7774ab | 434 | invalidate: |
d3600bcf | 435 | key = key_ref_to_ptr(key_ref); |
fd75815f | 436 | ret = 0; |
d3600bcf MZ |
437 | if (test_bit(KEY_FLAG_KEEP, &key->flags)) |
438 | ret = -EPERM; | |
1d6d167c | 439 | else |
d3600bcf | 440 | key_invalidate(key); |
0c7774ab | 441 | error_put: |
fd75815f DH |
442 | key_ref_put(key_ref); |
443 | error: | |
444 | kleave(" = %ld", ret); | |
445 | return ret; | |
446 | } | |
447 | ||
1da177e4 | 448 | /* |
973c9f4f DH |
449 | * Clear the specified keyring, creating an empty process keyring if one of the |
450 | * special keyring IDs is used. | |
451 | * | |
d3600bcf MZ |
452 | * The keyring must grant the caller Write permission and not have |
453 | * KEY_FLAG_KEEP set for this to work. If successful, 0 will be returned. | |
1da177e4 LT |
454 | */ |
455 | long keyctl_keyring_clear(key_serial_t ringid) | |
456 | { | |
664cceb0 | 457 | key_ref_t keyring_ref; |
d3600bcf | 458 | struct key *keyring; |
1da177e4 LT |
459 | long ret; |
460 | ||
f5895943 | 461 | keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE); |
664cceb0 DH |
462 | if (IS_ERR(keyring_ref)) { |
463 | ret = PTR_ERR(keyring_ref); | |
700920eb DH |
464 | |
465 | /* Root is permitted to invalidate certain special keyrings */ | |
466 | if (capable(CAP_SYS_ADMIN)) { | |
467 | keyring_ref = lookup_user_key(ringid, 0, 0); | |
468 | if (IS_ERR(keyring_ref)) | |
469 | goto error; | |
470 | if (test_bit(KEY_FLAG_ROOT_CAN_CLEAR, | |
471 | &key_ref_to_ptr(keyring_ref)->flags)) | |
472 | goto clear; | |
473 | goto error_put; | |
474 | } | |
475 | ||
1da177e4 LT |
476 | goto error; |
477 | } | |
478 | ||
700920eb | 479 | clear: |
d3600bcf MZ |
480 | keyring = key_ref_to_ptr(keyring_ref); |
481 | if (test_bit(KEY_FLAG_KEEP, &keyring->flags)) | |
482 | ret = -EPERM; | |
483 | else | |
484 | ret = keyring_clear(keyring); | |
700920eb | 485 | error_put: |
664cceb0 | 486 | key_ref_put(keyring_ref); |
c5b60b5e | 487 | error: |
1da177e4 | 488 | return ret; |
a8b17ed0 | 489 | } |
1da177e4 | 490 | |
1da177e4 | 491 | /* |
973c9f4f DH |
492 | * Create a link from a keyring to a key if there's no matching key in the |
493 | * keyring, otherwise replace the link to the matching key with a link to the | |
494 | * new key. | |
495 | * | |
496 | * The key must grant the caller Link permission and the the keyring must grant | |
497 | * the caller Write permission. Furthermore, if an additional link is created, | |
498 | * the keyring's quota will be extended. | |
499 | * | |
500 | * If successful, 0 will be returned. | |
1da177e4 LT |
501 | */ |
502 | long keyctl_keyring_link(key_serial_t id, key_serial_t ringid) | |
503 | { | |
664cceb0 | 504 | key_ref_t keyring_ref, key_ref; |
1da177e4 LT |
505 | long ret; |
506 | ||
f5895943 | 507 | keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE); |
664cceb0 DH |
508 | if (IS_ERR(keyring_ref)) { |
509 | ret = PTR_ERR(keyring_ref); | |
1da177e4 LT |
510 | goto error; |
511 | } | |
512 | ||
f5895943 | 513 | key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE, KEY_NEED_LINK); |
664cceb0 DH |
514 | if (IS_ERR(key_ref)) { |
515 | ret = PTR_ERR(key_ref); | |
1da177e4 LT |
516 | goto error2; |
517 | } | |
518 | ||
664cceb0 | 519 | ret = key_link(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref)); |
1da177e4 | 520 | |
664cceb0 | 521 | key_ref_put(key_ref); |
c5b60b5e | 522 | error2: |
664cceb0 | 523 | key_ref_put(keyring_ref); |
c5b60b5e | 524 | error: |
1da177e4 | 525 | return ret; |
a8b17ed0 | 526 | } |
1da177e4 | 527 | |
1da177e4 | 528 | /* |
973c9f4f DH |
529 | * Unlink a key from a keyring. |
530 | * | |
531 | * The keyring must grant the caller Write permission for this to work; the key | |
532 | * itself need not grant the caller anything. If the last link to a key is | |
533 | * removed then that key will be scheduled for destruction. | |
534 | * | |
d3600bcf MZ |
535 | * Keys or keyrings with KEY_FLAG_KEEP set should not be unlinked. |
536 | * | |
973c9f4f | 537 | * If successful, 0 will be returned. |
1da177e4 LT |
538 | */ |
539 | long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid) | |
540 | { | |
664cceb0 | 541 | key_ref_t keyring_ref, key_ref; |
d3600bcf | 542 | struct key *keyring, *key; |
1da177e4 LT |
543 | long ret; |
544 | ||
f5895943 | 545 | keyring_ref = lookup_user_key(ringid, 0, KEY_NEED_WRITE); |
664cceb0 DH |
546 | if (IS_ERR(keyring_ref)) { |
547 | ret = PTR_ERR(keyring_ref); | |
1da177e4 LT |
548 | goto error; |
549 | } | |
550 | ||
5593122e | 551 | key_ref = lookup_user_key(id, KEY_LOOKUP_FOR_UNLINK, 0); |
664cceb0 DH |
552 | if (IS_ERR(key_ref)) { |
553 | ret = PTR_ERR(key_ref); | |
1da177e4 LT |
554 | goto error2; |
555 | } | |
556 | ||
d3600bcf MZ |
557 | keyring = key_ref_to_ptr(keyring_ref); |
558 | key = key_ref_to_ptr(key_ref); | |
559 | if (test_bit(KEY_FLAG_KEEP, &keyring->flags) && | |
560 | test_bit(KEY_FLAG_KEEP, &key->flags)) | |
561 | ret = -EPERM; | |
562 | else | |
563 | ret = key_unlink(keyring, key); | |
1da177e4 | 564 | |
664cceb0 | 565 | key_ref_put(key_ref); |
c5b60b5e | 566 | error2: |
664cceb0 | 567 | key_ref_put(keyring_ref); |
c5b60b5e | 568 | error: |
1da177e4 | 569 | return ret; |
a8b17ed0 | 570 | } |
1da177e4 | 571 | |
1da177e4 | 572 | /* |
973c9f4f DH |
573 | * Return a description of a key to userspace. |
574 | * | |
575 | * The key must grant the caller View permission for this to work. | |
576 | * | |
577 | * If there's a buffer, we place up to buflen bytes of data into it formatted | |
578 | * in the following way: | |
579 | * | |
1da177e4 | 580 | * type;uid;gid;perm;description<NUL> |
973c9f4f DH |
581 | * |
582 | * If successful, we return the amount of description available, irrespective | |
583 | * of how much we may have copied into the buffer. | |
1da177e4 LT |
584 | */ |
585 | long keyctl_describe_key(key_serial_t keyid, | |
586 | char __user *buffer, | |
587 | size_t buflen) | |
588 | { | |
3e30148c | 589 | struct key *key, *instkey; |
664cceb0 | 590 | key_ref_t key_ref; |
aa9d4437 | 591 | char *infobuf; |
1da177e4 | 592 | long ret; |
aa9d4437 | 593 | int desclen, infolen; |
1da177e4 | 594 | |
f5895943 | 595 | key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_NEED_VIEW); |
664cceb0 | 596 | if (IS_ERR(key_ref)) { |
3e30148c DH |
597 | /* viewing a key under construction is permitted if we have the |
598 | * authorisation token handy */ | |
664cceb0 | 599 | if (PTR_ERR(key_ref) == -EACCES) { |
3e30148c DH |
600 | instkey = key_get_instantiation_authkey(keyid); |
601 | if (!IS_ERR(instkey)) { | |
602 | key_put(instkey); | |
8bbf4976 | 603 | key_ref = lookup_user_key(keyid, |
5593122e DH |
604 | KEY_LOOKUP_PARTIAL, |
605 | 0); | |
664cceb0 | 606 | if (!IS_ERR(key_ref)) |
3e30148c DH |
607 | goto okay; |
608 | } | |
609 | } | |
610 | ||
664cceb0 | 611 | ret = PTR_ERR(key_ref); |
1da177e4 LT |
612 | goto error; |
613 | } | |
614 | ||
3e30148c | 615 | okay: |
664cceb0 | 616 | key = key_ref_to_ptr(key_ref); |
aa9d4437 | 617 | desclen = strlen(key->description); |
664cceb0 | 618 | |
aa9d4437 DH |
619 | /* calculate how much information we're going to return */ |
620 | ret = -ENOMEM; | |
621 | infobuf = kasprintf(GFP_KERNEL, | |
622 | "%s;%d;%d;%08x;", | |
623 | key->type->name, | |
624 | from_kuid_munged(current_user_ns(), key->uid), | |
625 | from_kgid_munged(current_user_ns(), key->gid), | |
626 | key->perm); | |
627 | if (!infobuf) | |
628 | goto error2; | |
629 | infolen = strlen(infobuf); | |
630 | ret = infolen + desclen + 1; | |
1da177e4 LT |
631 | |
632 | /* consider returning the data */ | |
aa9d4437 DH |
633 | if (buffer && buflen >= ret) { |
634 | if (copy_to_user(buffer, infobuf, infolen) != 0 || | |
635 | copy_to_user(buffer + infolen, key->description, | |
636 | desclen + 1) != 0) | |
1da177e4 LT |
637 | ret = -EFAULT; |
638 | } | |
639 | ||
aa9d4437 | 640 | kfree(infobuf); |
c5b60b5e | 641 | error2: |
664cceb0 | 642 | key_ref_put(key_ref); |
c5b60b5e | 643 | error: |
1da177e4 | 644 | return ret; |
a8b17ed0 | 645 | } |
1da177e4 | 646 | |
1da177e4 | 647 | /* |
973c9f4f DH |
648 | * Search the specified keyring and any keyrings it links to for a matching |
649 | * key. Only keyrings that grant the caller Search permission will be searched | |
650 | * (this includes the starting keyring). Only keys with Search permission can | |
651 | * be found. | |
652 | * | |
653 | * If successful, the found key will be linked to the destination keyring if | |
654 | * supplied and the key has Link permission, and the found key ID will be | |
655 | * returned. | |
1da177e4 LT |
656 | */ |
657 | long keyctl_keyring_search(key_serial_t ringid, | |
658 | const char __user *_type, | |
659 | const char __user *_description, | |
660 | key_serial_t destringid) | |
661 | { | |
662 | struct key_type *ktype; | |
664cceb0 | 663 | key_ref_t keyring_ref, key_ref, dest_ref; |
1da177e4 | 664 | char type[32], *description; |
0cb409d9 | 665 | long ret; |
1da177e4 LT |
666 | |
667 | /* pull the type and description into kernel space */ | |
0cb409d9 | 668 | ret = key_get_type_from_user(type, _type, sizeof(type)); |
1da177e4 LT |
669 | if (ret < 0) |
670 | goto error; | |
1da177e4 | 671 | |
aa9d4437 | 672 | description = strndup_user(_description, KEY_MAX_DESC_SIZE); |
0cb409d9 DA |
673 | if (IS_ERR(description)) { |
674 | ret = PTR_ERR(description); | |
1da177e4 | 675 | goto error; |
0cb409d9 | 676 | } |
1da177e4 LT |
677 | |
678 | /* get the keyring at which to begin the search */ | |
f5895943 | 679 | keyring_ref = lookup_user_key(ringid, 0, KEY_NEED_SEARCH); |
664cceb0 DH |
680 | if (IS_ERR(keyring_ref)) { |
681 | ret = PTR_ERR(keyring_ref); | |
1da177e4 LT |
682 | goto error2; |
683 | } | |
684 | ||
685 | /* get the destination keyring if specified */ | |
664cceb0 | 686 | dest_ref = NULL; |
1da177e4 | 687 | if (destringid) { |
5593122e | 688 | dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE, |
f5895943 | 689 | KEY_NEED_WRITE); |
664cceb0 DH |
690 | if (IS_ERR(dest_ref)) { |
691 | ret = PTR_ERR(dest_ref); | |
1da177e4 LT |
692 | goto error3; |
693 | } | |
694 | } | |
695 | ||
696 | /* find the key type */ | |
697 | ktype = key_type_lookup(type); | |
698 | if (IS_ERR(ktype)) { | |
699 | ret = PTR_ERR(ktype); | |
700 | goto error4; | |
701 | } | |
702 | ||
703 | /* do the search */ | |
664cceb0 DH |
704 | key_ref = keyring_search(keyring_ref, ktype, description); |
705 | if (IS_ERR(key_ref)) { | |
706 | ret = PTR_ERR(key_ref); | |
1da177e4 LT |
707 | |
708 | /* treat lack or presence of a negative key the same */ | |
709 | if (ret == -EAGAIN) | |
710 | ret = -ENOKEY; | |
711 | goto error5; | |
712 | } | |
713 | ||
714 | /* link the resulting key to the destination keyring if we can */ | |
664cceb0 | 715 | if (dest_ref) { |
f5895943 | 716 | ret = key_permission(key_ref, KEY_NEED_LINK); |
29db9190 | 717 | if (ret < 0) |
1da177e4 LT |
718 | goto error6; |
719 | ||
664cceb0 | 720 | ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref)); |
1da177e4 LT |
721 | if (ret < 0) |
722 | goto error6; | |
723 | } | |
724 | ||
664cceb0 | 725 | ret = key_ref_to_ptr(key_ref)->serial; |
1da177e4 | 726 | |
c5b60b5e | 727 | error6: |
664cceb0 | 728 | key_ref_put(key_ref); |
c5b60b5e | 729 | error5: |
1da177e4 | 730 | key_type_put(ktype); |
c5b60b5e | 731 | error4: |
664cceb0 | 732 | key_ref_put(dest_ref); |
c5b60b5e | 733 | error3: |
664cceb0 | 734 | key_ref_put(keyring_ref); |
c5b60b5e | 735 | error2: |
1da177e4 | 736 | kfree(description); |
c5b60b5e | 737 | error: |
1da177e4 | 738 | return ret; |
a8b17ed0 | 739 | } |
1da177e4 | 740 | |
1da177e4 | 741 | /* |
973c9f4f DH |
742 | * Read a key's payload. |
743 | * | |
744 | * The key must either grant the caller Read permission, or it must grant the | |
745 | * caller Search permission when searched for from the process keyrings. | |
746 | * | |
747 | * If successful, we place up to buflen bytes of data into the buffer, if one | |
748 | * is provided, and return the amount of data that is available in the key, | |
749 | * irrespective of how much we copied into the buffer. | |
1da177e4 LT |
750 | */ |
751 | long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) | |
752 | { | |
664cceb0 DH |
753 | struct key *key; |
754 | key_ref_t key_ref; | |
1da177e4 LT |
755 | long ret; |
756 | ||
757 | /* find the key first */ | |
5593122e | 758 | key_ref = lookup_user_key(keyid, 0, 0); |
664cceb0 DH |
759 | if (IS_ERR(key_ref)) { |
760 | ret = -ENOKEY; | |
761 | goto error; | |
1da177e4 LT |
762 | } |
763 | ||
664cceb0 DH |
764 | key = key_ref_to_ptr(key_ref); |
765 | ||
766 | /* see if we can read it directly */ | |
f5895943 | 767 | ret = key_permission(key_ref, KEY_NEED_READ); |
29db9190 | 768 | if (ret == 0) |
664cceb0 | 769 | goto can_read_key; |
29db9190 DH |
770 | if (ret != -EACCES) |
771 | goto error; | |
664cceb0 DH |
772 | |
773 | /* we can't; see if it's searchable from this process's keyrings | |
774 | * - we automatically take account of the fact that it may be | |
775 | * dangling off an instantiation key | |
776 | */ | |
777 | if (!is_key_possessed(key_ref)) { | |
778 | ret = -EACCES; | |
779 | goto error2; | |
780 | } | |
1da177e4 LT |
781 | |
782 | /* the key is probably readable - now try to read it */ | |
c5b60b5e | 783 | can_read_key: |
b4a1b4f5 DH |
784 | ret = -EOPNOTSUPP; |
785 | if (key->type->read) { | |
786 | /* Read the data with the semaphore held (since we might sleep) | |
787 | * to protect against the key being updated or revoked. | |
788 | */ | |
789 | down_read(&key->sem); | |
790 | ret = key_validate(key); | |
791 | if (ret == 0) | |
1da177e4 | 792 | ret = key->type->read(key, buffer, buflen); |
b4a1b4f5 | 793 | up_read(&key->sem); |
1da177e4 LT |
794 | } |
795 | ||
c5b60b5e | 796 | error2: |
1da177e4 | 797 | key_put(key); |
c5b60b5e | 798 | error: |
1da177e4 | 799 | return ret; |
a8b17ed0 | 800 | } |
1da177e4 | 801 | |
1da177e4 | 802 | /* |
973c9f4f DH |
803 | * Change the ownership of a key |
804 | * | |
805 | * The key must grant the caller Setattr permission for this to work, though | |
806 | * the key need not be fully instantiated yet. For the UID to be changed, or | |
807 | * for the GID to be changed to a group the caller is not a member of, the | |
808 | * caller must have sysadmin capability. If either uid or gid is -1 then that | |
809 | * attribute is not changed. | |
810 | * | |
811 | * If the UID is to be changed, the new user must have sufficient quota to | |
812 | * accept the key. The quota deduction will be removed from the old user to | |
813 | * the new user should the attribute be changed. | |
814 | * | |
815 | * If successful, 0 will be returned. | |
1da177e4 | 816 | */ |
9a56c2db | 817 | long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group) |
1da177e4 | 818 | { |
5801649d | 819 | struct key_user *newowner, *zapowner = NULL; |
1da177e4 | 820 | struct key *key; |
664cceb0 | 821 | key_ref_t key_ref; |
1da177e4 | 822 | long ret; |
9a56c2db EB |
823 | kuid_t uid; |
824 | kgid_t gid; | |
825 | ||
826 | uid = make_kuid(current_user_ns(), user); | |
827 | gid = make_kgid(current_user_ns(), group); | |
828 | ret = -EINVAL; | |
829 | if ((user != (uid_t) -1) && !uid_valid(uid)) | |
830 | goto error; | |
831 | if ((group != (gid_t) -1) && !gid_valid(gid)) | |
832 | goto error; | |
1da177e4 LT |
833 | |
834 | ret = 0; | |
9a56c2db | 835 | if (user == (uid_t) -1 && group == (gid_t) -1) |
1da177e4 LT |
836 | goto error; |
837 | ||
5593122e | 838 | key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL, |
f5895943 | 839 | KEY_NEED_SETATTR); |
664cceb0 DH |
840 | if (IS_ERR(key_ref)) { |
841 | ret = PTR_ERR(key_ref); | |
1da177e4 LT |
842 | goto error; |
843 | } | |
844 | ||
664cceb0 DH |
845 | key = key_ref_to_ptr(key_ref); |
846 | ||
1da177e4 LT |
847 | /* make the changes with the locks held to prevent chown/chown races */ |
848 | ret = -EACCES; | |
849 | down_write(&key->sem); | |
1da177e4 LT |
850 | |
851 | if (!capable(CAP_SYS_ADMIN)) { | |
852 | /* only the sysadmin can chown a key to some other UID */ | |
9a56c2db | 853 | if (user != (uid_t) -1 && !uid_eq(key->uid, uid)) |
5801649d | 854 | goto error_put; |
1da177e4 LT |
855 | |
856 | /* only the sysadmin can set the key's GID to a group other | |
857 | * than one of those that the current process subscribes to */ | |
9a56c2db | 858 | if (group != (gid_t) -1 && !gid_eq(gid, key->gid) && !in_group_p(gid)) |
5801649d | 859 | goto error_put; |
1da177e4 LT |
860 | } |
861 | ||
5801649d | 862 | /* change the UID */ |
9a56c2db | 863 | if (user != (uid_t) -1 && !uid_eq(uid, key->uid)) { |
5801649d | 864 | ret = -ENOMEM; |
9a56c2db | 865 | newowner = key_user_lookup(uid); |
5801649d FT |
866 | if (!newowner) |
867 | goto error_put; | |
868 | ||
869 | /* transfer the quota burden to the new user */ | |
870 | if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) { | |
9a56c2db | 871 | unsigned maxkeys = uid_eq(uid, GLOBAL_ROOT_UID) ? |
0b77f5bf | 872 | key_quota_root_maxkeys : key_quota_maxkeys; |
9a56c2db | 873 | unsigned maxbytes = uid_eq(uid, GLOBAL_ROOT_UID) ? |
0b77f5bf DH |
874 | key_quota_root_maxbytes : key_quota_maxbytes; |
875 | ||
5801649d | 876 | spin_lock(&newowner->lock); |
0b77f5bf DH |
877 | if (newowner->qnkeys + 1 >= maxkeys || |
878 | newowner->qnbytes + key->quotalen >= maxbytes || | |
879 | newowner->qnbytes + key->quotalen < | |
880 | newowner->qnbytes) | |
5801649d FT |
881 | goto quota_overrun; |
882 | ||
883 | newowner->qnkeys++; | |
884 | newowner->qnbytes += key->quotalen; | |
885 | spin_unlock(&newowner->lock); | |
886 | ||
887 | spin_lock(&key->user->lock); | |
888 | key->user->qnkeys--; | |
889 | key->user->qnbytes -= key->quotalen; | |
890 | spin_unlock(&key->user->lock); | |
891 | } | |
892 | ||
893 | atomic_dec(&key->user->nkeys); | |
894 | atomic_inc(&newowner->nkeys); | |
895 | ||
896 | if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) { | |
897 | atomic_dec(&key->user->nikeys); | |
898 | atomic_inc(&newowner->nikeys); | |
899 | } | |
900 | ||
901 | zapowner = key->user; | |
902 | key->user = newowner; | |
903 | key->uid = uid; | |
1da177e4 LT |
904 | } |
905 | ||
906 | /* change the GID */ | |
9a56c2db | 907 | if (group != (gid_t) -1) |
1da177e4 LT |
908 | key->gid = gid; |
909 | ||
910 | ret = 0; | |
911 | ||
5801649d | 912 | error_put: |
1da177e4 LT |
913 | up_write(&key->sem); |
914 | key_put(key); | |
5801649d FT |
915 | if (zapowner) |
916 | key_user_put(zapowner); | |
917 | error: | |
1da177e4 LT |
918 | return ret; |
919 | ||
5801649d FT |
920 | quota_overrun: |
921 | spin_unlock(&newowner->lock); | |
922 | zapowner = newowner; | |
923 | ret = -EDQUOT; | |
924 | goto error_put; | |
a8b17ed0 | 925 | } |
5801649d | 926 | |
1da177e4 | 927 | /* |
973c9f4f DH |
928 | * Change the permission mask on a key. |
929 | * | |
930 | * The key must grant the caller Setattr permission for this to work, though | |
931 | * the key need not be fully instantiated yet. If the caller does not have | |
932 | * sysadmin capability, it may only change the permission on keys that it owns. | |
1da177e4 LT |
933 | */ |
934 | long keyctl_setperm_key(key_serial_t id, key_perm_t perm) | |
935 | { | |
936 | struct key *key; | |
664cceb0 | 937 | key_ref_t key_ref; |
1da177e4 LT |
938 | long ret; |
939 | ||
940 | ret = -EINVAL; | |
664cceb0 | 941 | if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL)) |
1da177e4 LT |
942 | goto error; |
943 | ||
5593122e | 944 | key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL, |
f5895943 | 945 | KEY_NEED_SETATTR); |
664cceb0 DH |
946 | if (IS_ERR(key_ref)) { |
947 | ret = PTR_ERR(key_ref); | |
1da177e4 LT |
948 | goto error; |
949 | } | |
950 | ||
664cceb0 DH |
951 | key = key_ref_to_ptr(key_ref); |
952 | ||
76d8aeab | 953 | /* make the changes with the locks held to prevent chown/chmod races */ |
1da177e4 LT |
954 | ret = -EACCES; |
955 | down_write(&key->sem); | |
1da177e4 | 956 | |
76d8aeab | 957 | /* if we're not the sysadmin, we can only change a key that we own */ |
9a56c2db | 958 | if (capable(CAP_SYS_ADMIN) || uid_eq(key->uid, current_fsuid())) { |
76d8aeab DH |
959 | key->perm = perm; |
960 | ret = 0; | |
961 | } | |
1da177e4 | 962 | |
1da177e4 LT |
963 | up_write(&key->sem); |
964 | key_put(key); | |
76d8aeab | 965 | error: |
1da177e4 | 966 | return ret; |
a8b17ed0 | 967 | } |
1da177e4 | 968 | |
8bbf4976 | 969 | /* |
973c9f4f DH |
970 | * Get the destination keyring for instantiation and check that the caller has |
971 | * Write permission on it. | |
8bbf4976 DH |
972 | */ |
973 | static long get_instantiation_keyring(key_serial_t ringid, | |
974 | struct request_key_auth *rka, | |
975 | struct key **_dest_keyring) | |
976 | { | |
977 | key_ref_t dkref; | |
978 | ||
eca1bf5b DH |
979 | *_dest_keyring = NULL; |
980 | ||
8bbf4976 | 981 | /* just return a NULL pointer if we weren't asked to make a link */ |
eca1bf5b | 982 | if (ringid == 0) |
8bbf4976 | 983 | return 0; |
8bbf4976 DH |
984 | |
985 | /* if a specific keyring is nominated by ID, then use that */ | |
986 | if (ringid > 0) { | |
f5895943 | 987 | dkref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE); |
8bbf4976 DH |
988 | if (IS_ERR(dkref)) |
989 | return PTR_ERR(dkref); | |
990 | *_dest_keyring = key_ref_to_ptr(dkref); | |
991 | return 0; | |
992 | } | |
993 | ||
994 | if (ringid == KEY_SPEC_REQKEY_AUTH_KEY) | |
995 | return -EINVAL; | |
996 | ||
997 | /* otherwise specify the destination keyring recorded in the | |
998 | * authorisation key (any KEY_SPEC_*_KEYRING) */ | |
999 | if (ringid >= KEY_SPEC_REQUESTOR_KEYRING) { | |
21279cfa | 1000 | *_dest_keyring = key_get(rka->dest_keyring); |
8bbf4976 DH |
1001 | return 0; |
1002 | } | |
1003 | ||
1004 | return -ENOKEY; | |
1005 | } | |
1006 | ||
d84f4f99 | 1007 | /* |
973c9f4f | 1008 | * Change the request_key authorisation key on the current process. |
d84f4f99 DH |
1009 | */ |
1010 | static int keyctl_change_reqkey_auth(struct key *key) | |
1011 | { | |
1012 | struct cred *new; | |
1013 | ||
1014 | new = prepare_creds(); | |
1015 | if (!new) | |
1016 | return -ENOMEM; | |
1017 | ||
1018 | key_put(new->request_key_auth); | |
1019 | new->request_key_auth = key_get(key); | |
1020 | ||
1021 | return commit_creds(new); | |
1022 | } | |
1023 | ||
1da177e4 | 1024 | /* |
973c9f4f DH |
1025 | * Instantiate a key with the specified payload and link the key into the |
1026 | * destination keyring if one is given. | |
1027 | * | |
1028 | * The caller must have the appropriate instantiation permit set for this to | |
1029 | * work (see keyctl_assume_authority). No other permissions are required. | |
1030 | * | |
1031 | * If successful, 0 will be returned. | |
1da177e4 | 1032 | */ |
ee009e4a | 1033 | long keyctl_instantiate_key_common(key_serial_t id, |
b353a1f7 | 1034 | struct iov_iter *from, |
ee009e4a | 1035 | key_serial_t ringid) |
1da177e4 | 1036 | { |
d84f4f99 | 1037 | const struct cred *cred = current_cred(); |
3e30148c | 1038 | struct request_key_auth *rka; |
8bbf4976 | 1039 | struct key *instkey, *dest_keyring; |
b353a1f7 | 1040 | size_t plen = from ? iov_iter_count(from) : 0; |
1da177e4 LT |
1041 | void *payload; |
1042 | long ret; | |
1043 | ||
d84f4f99 DH |
1044 | kenter("%d,,%zu,%d", id, plen, ringid); |
1045 | ||
b353a1f7 AV |
1046 | if (!plen) |
1047 | from = NULL; | |
1048 | ||
1da177e4 | 1049 | ret = -EINVAL; |
38bbca6b | 1050 | if (plen > 1024 * 1024 - 1) |
1da177e4 LT |
1051 | goto error; |
1052 | ||
b5f545c8 DH |
1053 | /* the appropriate instantiation authorisation key must have been |
1054 | * assumed before calling this */ | |
1055 | ret = -EPERM; | |
d84f4f99 | 1056 | instkey = cred->request_key_auth; |
b5f545c8 DH |
1057 | if (!instkey) |
1058 | goto error; | |
1059 | ||
146aa8b1 | 1060 | rka = instkey->payload.data[0]; |
b5f545c8 DH |
1061 | if (rka->target_key->serial != id) |
1062 | goto error; | |
1063 | ||
1da177e4 LT |
1064 | /* pull the payload in if one was supplied */ |
1065 | payload = NULL; | |
1066 | ||
b353a1f7 | 1067 | if (from) { |
1da177e4 | 1068 | ret = -ENOMEM; |
752ade68 MH |
1069 | payload = kvmalloc(plen, GFP_KERNEL); |
1070 | if (!payload) | |
1071 | goto error; | |
1da177e4 | 1072 | |
b353a1f7 | 1073 | ret = -EFAULT; |
cbbd26b8 | 1074 | if (!copy_from_iter_full(payload, plen, from)) |
1da177e4 LT |
1075 | goto error2; |
1076 | } | |
1077 | ||
3e30148c DH |
1078 | /* find the destination keyring amongst those belonging to the |
1079 | * requesting task */ | |
8bbf4976 DH |
1080 | ret = get_instantiation_keyring(ringid, rka, &dest_keyring); |
1081 | if (ret < 0) | |
1082 | goto error2; | |
1da177e4 LT |
1083 | |
1084 | /* instantiate the key and link it into a keyring */ | |
3e30148c | 1085 | ret = key_instantiate_and_link(rka->target_key, payload, plen, |
8bbf4976 | 1086 | dest_keyring, instkey); |
1da177e4 | 1087 | |
8bbf4976 | 1088 | key_put(dest_keyring); |
b5f545c8 DH |
1089 | |
1090 | /* discard the assumed authority if it's just been disabled by | |
1091 | * instantiation of the key */ | |
d84f4f99 DH |
1092 | if (ret == 0) |
1093 | keyctl_change_reqkey_auth(NULL); | |
b5f545c8 DH |
1094 | |
1095 | error2: | |
b353a1f7 | 1096 | kvfree(payload); |
b5f545c8 | 1097 | error: |
1da177e4 | 1098 | return ret; |
a8b17ed0 | 1099 | } |
1da177e4 | 1100 | |
ee009e4a DH |
1101 | /* |
1102 | * Instantiate a key with the specified payload and link the key into the | |
1103 | * destination keyring if one is given. | |
1104 | * | |
1105 | * The caller must have the appropriate instantiation permit set for this to | |
1106 | * work (see keyctl_assume_authority). No other permissions are required. | |
1107 | * | |
1108 | * If successful, 0 will be returned. | |
1109 | */ | |
1110 | long keyctl_instantiate_key(key_serial_t id, | |
1111 | const void __user *_payload, | |
1112 | size_t plen, | |
1113 | key_serial_t ringid) | |
1114 | { | |
1115 | if (_payload && plen) { | |
b353a1f7 AV |
1116 | struct iovec iov; |
1117 | struct iov_iter from; | |
1118 | int ret; | |
ee009e4a | 1119 | |
b353a1f7 AV |
1120 | ret = import_single_range(WRITE, (void __user *)_payload, plen, |
1121 | &iov, &from); | |
1122 | if (unlikely(ret)) | |
1123 | return ret; | |
1124 | ||
1125 | return keyctl_instantiate_key_common(id, &from, ringid); | |
ee009e4a DH |
1126 | } |
1127 | ||
b353a1f7 | 1128 | return keyctl_instantiate_key_common(id, NULL, ringid); |
ee009e4a DH |
1129 | } |
1130 | ||
1131 | /* | |
1132 | * Instantiate a key with the specified multipart payload and link the key into | |
1133 | * the destination keyring if one is given. | |
1134 | * | |
1135 | * The caller must have the appropriate instantiation permit set for this to | |
1136 | * work (see keyctl_assume_authority). No other permissions are required. | |
1137 | * | |
1138 | * If successful, 0 will be returned. | |
1139 | */ | |
1140 | long keyctl_instantiate_key_iov(key_serial_t id, | |
1141 | const struct iovec __user *_payload_iov, | |
1142 | unsigned ioc, | |
1143 | key_serial_t ringid) | |
1144 | { | |
1145 | struct iovec iovstack[UIO_FASTIOV], *iov = iovstack; | |
b353a1f7 | 1146 | struct iov_iter from; |
ee009e4a DH |
1147 | long ret; |
1148 | ||
b353a1f7 AV |
1149 | if (!_payload_iov) |
1150 | ioc = 0; | |
ee009e4a | 1151 | |
b353a1f7 AV |
1152 | ret = import_iovec(WRITE, _payload_iov, ioc, |
1153 | ARRAY_SIZE(iovstack), &iov, &from); | |
ee009e4a | 1154 | if (ret < 0) |
b353a1f7 AV |
1155 | return ret; |
1156 | ret = keyctl_instantiate_key_common(id, &from, ringid); | |
1157 | kfree(iov); | |
ee009e4a | 1158 | return ret; |
ee009e4a DH |
1159 | } |
1160 | ||
1da177e4 | 1161 | /* |
973c9f4f DH |
1162 | * Negatively instantiate the key with the given timeout (in seconds) and link |
1163 | * the key into the destination keyring if one is given. | |
1164 | * | |
1165 | * The caller must have the appropriate instantiation permit set for this to | |
1166 | * work (see keyctl_assume_authority). No other permissions are required. | |
1167 | * | |
1168 | * The key and any links to the key will be automatically garbage collected | |
1169 | * after the timeout expires. | |
1170 | * | |
1171 | * Negative keys are used to rate limit repeated request_key() calls by causing | |
1172 | * them to return -ENOKEY until the negative key expires. | |
1173 | * | |
1174 | * If successful, 0 will be returned. | |
1da177e4 LT |
1175 | */ |
1176 | long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid) | |
fdd1b945 DH |
1177 | { |
1178 | return keyctl_reject_key(id, timeout, ENOKEY, ringid); | |
1179 | } | |
1180 | ||
1181 | /* | |
1182 | * Negatively instantiate the key with the given timeout (in seconds) and error | |
1183 | * code and link the key into the destination keyring if one is given. | |
1184 | * | |
1185 | * The caller must have the appropriate instantiation permit set for this to | |
1186 | * work (see keyctl_assume_authority). No other permissions are required. | |
1187 | * | |
1188 | * The key and any links to the key will be automatically garbage collected | |
1189 | * after the timeout expires. | |
1190 | * | |
1191 | * Negative keys are used to rate limit repeated request_key() calls by causing | |
1192 | * them to return the specified error code until the negative key expires. | |
1193 | * | |
1194 | * If successful, 0 will be returned. | |
1195 | */ | |
1196 | long keyctl_reject_key(key_serial_t id, unsigned timeout, unsigned error, | |
1197 | key_serial_t ringid) | |
1da177e4 | 1198 | { |
d84f4f99 | 1199 | const struct cred *cred = current_cred(); |
3e30148c | 1200 | struct request_key_auth *rka; |
8bbf4976 | 1201 | struct key *instkey, *dest_keyring; |
1da177e4 LT |
1202 | long ret; |
1203 | ||
fdd1b945 DH |
1204 | kenter("%d,%u,%u,%d", id, timeout, error, ringid); |
1205 | ||
1206 | /* must be a valid error code and mustn't be a kernel special */ | |
1207 | if (error <= 0 || | |
1208 | error >= MAX_ERRNO || | |
1209 | error == ERESTARTSYS || | |
1210 | error == ERESTARTNOINTR || | |
1211 | error == ERESTARTNOHAND || | |
1212 | error == ERESTART_RESTARTBLOCK) | |
1213 | return -EINVAL; | |
d84f4f99 | 1214 | |
b5f545c8 DH |
1215 | /* the appropriate instantiation authorisation key must have been |
1216 | * assumed before calling this */ | |
1217 | ret = -EPERM; | |
d84f4f99 | 1218 | instkey = cred->request_key_auth; |
b5f545c8 | 1219 | if (!instkey) |
1da177e4 | 1220 | goto error; |
1da177e4 | 1221 | |
146aa8b1 | 1222 | rka = instkey->payload.data[0]; |
b5f545c8 DH |
1223 | if (rka->target_key->serial != id) |
1224 | goto error; | |
3e30148c | 1225 | |
1da177e4 LT |
1226 | /* find the destination keyring if present (which must also be |
1227 | * writable) */ | |
8bbf4976 DH |
1228 | ret = get_instantiation_keyring(ringid, rka, &dest_keyring); |
1229 | if (ret < 0) | |
1230 | goto error; | |
1da177e4 LT |
1231 | |
1232 | /* instantiate the key and link it into a keyring */ | |
fdd1b945 | 1233 | ret = key_reject_and_link(rka->target_key, timeout, error, |
8bbf4976 | 1234 | dest_keyring, instkey); |
1da177e4 | 1235 | |
8bbf4976 | 1236 | key_put(dest_keyring); |
b5f545c8 DH |
1237 | |
1238 | /* discard the assumed authority if it's just been disabled by | |
1239 | * instantiation of the key */ | |
d84f4f99 DH |
1240 | if (ret == 0) |
1241 | keyctl_change_reqkey_auth(NULL); | |
b5f545c8 DH |
1242 | |
1243 | error: | |
1da177e4 | 1244 | return ret; |
a8b17ed0 | 1245 | } |
1da177e4 | 1246 | |
3e30148c | 1247 | /* |
973c9f4f DH |
1248 | * Read or set the default keyring in which request_key() will cache keys and |
1249 | * return the old setting. | |
1250 | * | |
c9f838d1 EB |
1251 | * If a thread or process keyring is specified then it will be created if it |
1252 | * doesn't yet exist. The old setting will be returned if successful. | |
3e30148c DH |
1253 | */ |
1254 | long keyctl_set_reqkey_keyring(int reqkey_defl) | |
1255 | { | |
d84f4f99 DH |
1256 | struct cred *new; |
1257 | int ret, old_setting; | |
1258 | ||
1259 | old_setting = current_cred_xxx(jit_keyring); | |
1260 | ||
1261 | if (reqkey_defl == KEY_REQKEY_DEFL_NO_CHANGE) | |
1262 | return old_setting; | |
1263 | ||
1264 | new = prepare_creds(); | |
1265 | if (!new) | |
1266 | return -ENOMEM; | |
3e30148c DH |
1267 | |
1268 | switch (reqkey_defl) { | |
1269 | case KEY_REQKEY_DEFL_THREAD_KEYRING: | |
d84f4f99 | 1270 | ret = install_thread_keyring_to_cred(new); |
3e30148c | 1271 | if (ret < 0) |
d84f4f99 | 1272 | goto error; |
3e30148c DH |
1273 | goto set; |
1274 | ||
1275 | case KEY_REQKEY_DEFL_PROCESS_KEYRING: | |
d84f4f99 | 1276 | ret = install_process_keyring_to_cred(new); |
c9f838d1 EB |
1277 | if (ret < 0) |
1278 | goto error; | |
d84f4f99 | 1279 | goto set; |
3e30148c DH |
1280 | |
1281 | case KEY_REQKEY_DEFL_DEFAULT: | |
1282 | case KEY_REQKEY_DEFL_SESSION_KEYRING: | |
1283 | case KEY_REQKEY_DEFL_USER_KEYRING: | |
1284 | case KEY_REQKEY_DEFL_USER_SESSION_KEYRING: | |
d84f4f99 DH |
1285 | case KEY_REQKEY_DEFL_REQUESTOR_KEYRING: |
1286 | goto set; | |
3e30148c DH |
1287 | |
1288 | case KEY_REQKEY_DEFL_NO_CHANGE: | |
3e30148c DH |
1289 | case KEY_REQKEY_DEFL_GROUP_KEYRING: |
1290 | default: | |
d84f4f99 DH |
1291 | ret = -EINVAL; |
1292 | goto error; | |
3e30148c DH |
1293 | } |
1294 | ||
d84f4f99 DH |
1295 | set: |
1296 | new->jit_keyring = reqkey_defl; | |
1297 | commit_creds(new); | |
1298 | return old_setting; | |
1299 | error: | |
1300 | abort_creds(new); | |
4303ef19 | 1301 | return ret; |
a8b17ed0 | 1302 | } |
d84f4f99 | 1303 | |
017679c4 | 1304 | /* |
973c9f4f DH |
1305 | * Set or clear the timeout on a key. |
1306 | * | |
1307 | * Either the key must grant the caller Setattr permission or else the caller | |
1308 | * must hold an instantiation authorisation token for the key. | |
1309 | * | |
1310 | * The timeout is either 0 to clear the timeout, or a number of seconds from | |
1311 | * the current time. The key and any links to the key will be automatically | |
1312 | * garbage collected after the timeout expires. | |
1313 | * | |
d3600bcf MZ |
1314 | * Keys with KEY_FLAG_KEEP set should not be timed out. |
1315 | * | |
973c9f4f | 1316 | * If successful, 0 is returned. |
017679c4 DH |
1317 | */ |
1318 | long keyctl_set_timeout(key_serial_t id, unsigned timeout) | |
1319 | { | |
9156235b | 1320 | struct key *key, *instkey; |
017679c4 | 1321 | key_ref_t key_ref; |
017679c4 DH |
1322 | long ret; |
1323 | ||
5593122e | 1324 | key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL, |
f5895943 | 1325 | KEY_NEED_SETATTR); |
017679c4 | 1326 | if (IS_ERR(key_ref)) { |
9156235b DH |
1327 | /* setting the timeout on a key under construction is permitted |
1328 | * if we have the authorisation token handy */ | |
1329 | if (PTR_ERR(key_ref) == -EACCES) { | |
1330 | instkey = key_get_instantiation_authkey(id); | |
1331 | if (!IS_ERR(instkey)) { | |
1332 | key_put(instkey); | |
1333 | key_ref = lookup_user_key(id, | |
1334 | KEY_LOOKUP_PARTIAL, | |
1335 | 0); | |
1336 | if (!IS_ERR(key_ref)) | |
1337 | goto okay; | |
1338 | } | |
1339 | } | |
1340 | ||
017679c4 DH |
1341 | ret = PTR_ERR(key_ref); |
1342 | goto error; | |
1343 | } | |
1344 | ||
9156235b | 1345 | okay: |
017679c4 | 1346 | key = key_ref_to_ptr(key_ref); |
1d6d167c | 1347 | ret = 0; |
d3600bcf MZ |
1348 | if (test_bit(KEY_FLAG_KEEP, &key->flags)) |
1349 | ret = -EPERM; | |
1d6d167c | 1350 | else |
d3600bcf | 1351 | key_set_timeout(key, timeout); |
017679c4 DH |
1352 | key_put(key); |
1353 | ||
017679c4 DH |
1354 | error: |
1355 | return ret; | |
a8b17ed0 | 1356 | } |
017679c4 | 1357 | |
b5f545c8 | 1358 | /* |
973c9f4f DH |
1359 | * Assume (or clear) the authority to instantiate the specified key. |
1360 | * | |
1361 | * This sets the authoritative token currently in force for key instantiation. | |
1362 | * This must be done for a key to be instantiated. It has the effect of making | |
1363 | * available all the keys from the caller of the request_key() that created a | |
1364 | * key to request_key() calls made by the caller of this function. | |
1365 | * | |
1366 | * The caller must have the instantiation key in their process keyrings with a | |
1367 | * Search permission grant available to the caller. | |
1368 | * | |
1369 | * If the ID given is 0, then the setting will be cleared and 0 returned. | |
1370 | * | |
1371 | * If the ID given has a matching an authorisation key, then that key will be | |
1372 | * set and its ID will be returned. The authorisation key can be read to get | |
1373 | * the callout information passed to request_key(). | |
b5f545c8 DH |
1374 | */ |
1375 | long keyctl_assume_authority(key_serial_t id) | |
1376 | { | |
1377 | struct key *authkey; | |
1378 | long ret; | |
1379 | ||
1380 | /* special key IDs aren't permitted */ | |
1381 | ret = -EINVAL; | |
1382 | if (id < 0) | |
1383 | goto error; | |
1384 | ||
1385 | /* we divest ourselves of authority if given an ID of 0 */ | |
1386 | if (id == 0) { | |
d84f4f99 | 1387 | ret = keyctl_change_reqkey_auth(NULL); |
b5f545c8 DH |
1388 | goto error; |
1389 | } | |
1390 | ||
1391 | /* attempt to assume the authority temporarily granted to us whilst we | |
1392 | * instantiate the specified key | |
1393 | * - the authorisation key must be in the current task's keyrings | |
1394 | * somewhere | |
1395 | */ | |
1396 | authkey = key_get_instantiation_authkey(id); | |
1397 | if (IS_ERR(authkey)) { | |
1398 | ret = PTR_ERR(authkey); | |
1399 | goto error; | |
1400 | } | |
1401 | ||
d84f4f99 DH |
1402 | ret = keyctl_change_reqkey_auth(authkey); |
1403 | if (ret < 0) | |
1404 | goto error; | |
1405 | key_put(authkey); | |
b5f545c8 | 1406 | |
d84f4f99 | 1407 | ret = authkey->serial; |
b5f545c8 DH |
1408 | error: |
1409 | return ret; | |
a8b17ed0 | 1410 | } |
b5f545c8 | 1411 | |
70a5bb72 | 1412 | /* |
973c9f4f DH |
1413 | * Get a key's the LSM security label. |
1414 | * | |
1415 | * The key must grant the caller View permission for this to work. | |
1416 | * | |
1417 | * If there's a buffer, then up to buflen bytes of data will be placed into it. | |
1418 | * | |
1419 | * If successful, the amount of information available will be returned, | |
1420 | * irrespective of how much was copied (including the terminal NUL). | |
70a5bb72 DH |
1421 | */ |
1422 | long keyctl_get_security(key_serial_t keyid, | |
1423 | char __user *buffer, | |
1424 | size_t buflen) | |
1425 | { | |
1426 | struct key *key, *instkey; | |
1427 | key_ref_t key_ref; | |
1428 | char *context; | |
1429 | long ret; | |
1430 | ||
f5895943 | 1431 | key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_NEED_VIEW); |
70a5bb72 DH |
1432 | if (IS_ERR(key_ref)) { |
1433 | if (PTR_ERR(key_ref) != -EACCES) | |
1434 | return PTR_ERR(key_ref); | |
1435 | ||
1436 | /* viewing a key under construction is also permitted if we | |
1437 | * have the authorisation token handy */ | |
1438 | instkey = key_get_instantiation_authkey(keyid); | |
1439 | if (IS_ERR(instkey)) | |
fa1cc7b5 | 1440 | return PTR_ERR(instkey); |
70a5bb72 DH |
1441 | key_put(instkey); |
1442 | ||
5593122e | 1443 | key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, 0); |
70a5bb72 DH |
1444 | if (IS_ERR(key_ref)) |
1445 | return PTR_ERR(key_ref); | |
1446 | } | |
1447 | ||
1448 | key = key_ref_to_ptr(key_ref); | |
1449 | ret = security_key_getsecurity(key, &context); | |
1450 | if (ret == 0) { | |
1451 | /* if no information was returned, give userspace an empty | |
1452 | * string */ | |
1453 | ret = 1; | |
1454 | if (buffer && buflen > 0 && | |
1455 | copy_to_user(buffer, "", 1) != 0) | |
1456 | ret = -EFAULT; | |
1457 | } else if (ret > 0) { | |
1458 | /* return as much data as there's room for */ | |
1459 | if (buffer && buflen > 0) { | |
1460 | if (buflen > ret) | |
1461 | buflen = ret; | |
1462 | ||
1463 | if (copy_to_user(buffer, context, buflen) != 0) | |
1464 | ret = -EFAULT; | |
1465 | } | |
1466 | ||
1467 | kfree(context); | |
1468 | } | |
1469 | ||
1470 | key_ref_put(key_ref); | |
1471 | return ret; | |
1472 | } | |
1473 | ||
ee18d64c | 1474 | /* |
973c9f4f DH |
1475 | * Attempt to install the calling process's session keyring on the process's |
1476 | * parent process. | |
1477 | * | |
1478 | * The keyring must exist and must grant the caller LINK permission, and the | |
1479 | * parent process must be single-threaded and must have the same effective | |
1480 | * ownership as this process and mustn't be SUID/SGID. | |
1481 | * | |
1482 | * The keyring will be emplaced on the parent when it next resumes userspace. | |
1483 | * | |
1484 | * If successful, 0 will be returned. | |
ee18d64c DH |
1485 | */ |
1486 | long keyctl_session_to_parent(void) | |
1487 | { | |
1488 | struct task_struct *me, *parent; | |
1489 | const struct cred *mycred, *pcred; | |
67d12145 | 1490 | struct callback_head *newwork, *oldwork; |
ee18d64c | 1491 | key_ref_t keyring_r; |
413cd3d9 | 1492 | struct cred *cred; |
ee18d64c DH |
1493 | int ret; |
1494 | ||
f5895943 | 1495 | keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_NEED_LINK); |
ee18d64c DH |
1496 | if (IS_ERR(keyring_r)) |
1497 | return PTR_ERR(keyring_r); | |
1498 | ||
413cd3d9 | 1499 | ret = -ENOMEM; |
413cd3d9 | 1500 | |
ee18d64c DH |
1501 | /* our parent is going to need a new cred struct, a new tgcred struct |
1502 | * and new security data, so we allocate them here to prevent ENOMEM in | |
1503 | * our parent */ | |
ee18d64c DH |
1504 | cred = cred_alloc_blank(); |
1505 | if (!cred) | |
67d12145 AV |
1506 | goto error_keyring; |
1507 | newwork = &cred->rcu; | |
ee18d64c | 1508 | |
3a50597d DH |
1509 | cred->session_keyring = key_ref_to_ptr(keyring_r); |
1510 | keyring_r = NULL; | |
67d12145 | 1511 | init_task_work(newwork, key_change_session_keyring); |
ee18d64c DH |
1512 | |
1513 | me = current; | |
9d1ac65a | 1514 | rcu_read_lock(); |
ee18d64c DH |
1515 | write_lock_irq(&tasklist_lock); |
1516 | ||
ee18d64c | 1517 | ret = -EPERM; |
413cd3d9 ON |
1518 | oldwork = NULL; |
1519 | parent = me->real_parent; | |
ee18d64c DH |
1520 | |
1521 | /* the parent mustn't be init and mustn't be a kernel thread */ | |
1522 | if (parent->pid <= 1 || !parent->mm) | |
413cd3d9 | 1523 | goto unlock; |
ee18d64c DH |
1524 | |
1525 | /* the parent must be single threaded */ | |
dd98acf7 | 1526 | if (!thread_group_empty(parent)) |
413cd3d9 | 1527 | goto unlock; |
ee18d64c DH |
1528 | |
1529 | /* the parent and the child must have different session keyrings or | |
1530 | * there's no point */ | |
1531 | mycred = current_cred(); | |
1532 | pcred = __task_cred(parent); | |
1533 | if (mycred == pcred || | |
3a50597d | 1534 | mycred->session_keyring == pcred->session_keyring) { |
413cd3d9 ON |
1535 | ret = 0; |
1536 | goto unlock; | |
1537 | } | |
ee18d64c DH |
1538 | |
1539 | /* the parent must have the same effective ownership and mustn't be | |
1540 | * SUID/SGID */ | |
9a56c2db EB |
1541 | if (!uid_eq(pcred->uid, mycred->euid) || |
1542 | !uid_eq(pcred->euid, mycred->euid) || | |
1543 | !uid_eq(pcred->suid, mycred->euid) || | |
1544 | !gid_eq(pcred->gid, mycred->egid) || | |
1545 | !gid_eq(pcred->egid, mycred->egid) || | |
1546 | !gid_eq(pcred->sgid, mycred->egid)) | |
413cd3d9 | 1547 | goto unlock; |
ee18d64c DH |
1548 | |
1549 | /* the keyrings must have the same UID */ | |
3a50597d | 1550 | if ((pcred->session_keyring && |
2a74dbb9 LT |
1551 | !uid_eq(pcred->session_keyring->uid, mycred->euid)) || |
1552 | !uid_eq(mycred->session_keyring->uid, mycred->euid)) | |
413cd3d9 | 1553 | goto unlock; |
ee18d64c | 1554 | |
413cd3d9 ON |
1555 | /* cancel an already pending keyring replacement */ |
1556 | oldwork = task_work_cancel(parent, key_change_session_keyring); | |
ee18d64c DH |
1557 | |
1558 | /* the replacement session keyring is applied just prior to userspace | |
1559 | * restarting */ | |
67d12145 | 1560 | ret = task_work_add(parent, newwork, true); |
413cd3d9 ON |
1561 | if (!ret) |
1562 | newwork = NULL; | |
1563 | unlock: | |
ee18d64c | 1564 | write_unlock_irq(&tasklist_lock); |
9d1ac65a | 1565 | rcu_read_unlock(); |
67d12145 AV |
1566 | if (oldwork) |
1567 | put_cred(container_of(oldwork, struct cred, rcu)); | |
1568 | if (newwork) | |
1569 | put_cred(cred); | |
ee18d64c DH |
1570 | return ret; |
1571 | ||
1572 | error_keyring: | |
1573 | key_ref_put(keyring_r); | |
1574 | return ret; | |
1575 | } | |
1576 | ||
6563c91f MM |
1577 | /* |
1578 | * Apply a restriction to a given keyring. | |
1579 | * | |
1580 | * The caller must have Setattr permission to change keyring restrictions. | |
1581 | * | |
1582 | * The requested type name may be a NULL pointer to reject all attempts | |
1583 | * to link to the keyring. If _type is non-NULL, _restriction can be | |
1584 | * NULL or a pointer to a string describing the restriction. If _type is | |
1585 | * NULL, _restriction must also be NULL. | |
1586 | * | |
1587 | * Returns 0 if successful. | |
1588 | */ | |
1589 | long keyctl_restrict_keyring(key_serial_t id, const char __user *_type, | |
1590 | const char __user *_restriction) | |
1591 | { | |
1592 | key_ref_t key_ref; | |
1593 | bool link_reject = !_type; | |
1594 | char type[32]; | |
1595 | char *restriction = NULL; | |
1596 | long ret; | |
1597 | ||
1598 | key_ref = lookup_user_key(id, 0, KEY_NEED_SETATTR); | |
1599 | if (IS_ERR(key_ref)) | |
1600 | return PTR_ERR(key_ref); | |
1601 | ||
1602 | if (_type) { | |
1603 | ret = key_get_type_from_user(type, _type, sizeof(type)); | |
1604 | if (ret < 0) | |
1605 | goto error; | |
1606 | } | |
1607 | ||
1608 | if (_restriction) { | |
1609 | if (!_type) { | |
1610 | ret = -EINVAL; | |
1611 | goto error; | |
1612 | } | |
1613 | ||
1614 | restriction = strndup_user(_restriction, PAGE_SIZE); | |
1615 | if (IS_ERR(restriction)) { | |
1616 | ret = PTR_ERR(restriction); | |
1617 | goto error; | |
1618 | } | |
1619 | } | |
1620 | ||
1621 | ret = keyring_restrict(key_ref, link_reject ? NULL : type, restriction); | |
1622 | kfree(restriction); | |
1623 | ||
1624 | error: | |
1625 | key_ref_put(key_ref); | |
1626 | ||
1627 | return ret; | |
1628 | } | |
1629 | ||
1da177e4 | 1630 | /* |
973c9f4f | 1631 | * The key control system call |
1da177e4 | 1632 | */ |
938bb9f5 HC |
1633 | SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, |
1634 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 LT |
1635 | { |
1636 | switch (option) { | |
1637 | case KEYCTL_GET_KEYRING_ID: | |
1638 | return keyctl_get_keyring_ID((key_serial_t) arg2, | |
1639 | (int) arg3); | |
1640 | ||
1641 | case KEYCTL_JOIN_SESSION_KEYRING: | |
1642 | return keyctl_join_session_keyring((const char __user *) arg2); | |
1643 | ||
1644 | case KEYCTL_UPDATE: | |
1645 | return keyctl_update_key((key_serial_t) arg2, | |
1646 | (const void __user *) arg3, | |
1647 | (size_t) arg4); | |
1648 | ||
1649 | case KEYCTL_REVOKE: | |
1650 | return keyctl_revoke_key((key_serial_t) arg2); | |
1651 | ||
1652 | case KEYCTL_DESCRIBE: | |
1653 | return keyctl_describe_key((key_serial_t) arg2, | |
1654 | (char __user *) arg3, | |
1655 | (unsigned) arg4); | |
1656 | ||
1657 | case KEYCTL_CLEAR: | |
1658 | return keyctl_keyring_clear((key_serial_t) arg2); | |
1659 | ||
1660 | case KEYCTL_LINK: | |
1661 | return keyctl_keyring_link((key_serial_t) arg2, | |
1662 | (key_serial_t) arg3); | |
1663 | ||
1664 | case KEYCTL_UNLINK: | |
1665 | return keyctl_keyring_unlink((key_serial_t) arg2, | |
1666 | (key_serial_t) arg3); | |
1667 | ||
1668 | case KEYCTL_SEARCH: | |
1669 | return keyctl_keyring_search((key_serial_t) arg2, | |
1670 | (const char __user *) arg3, | |
1671 | (const char __user *) arg4, | |
1672 | (key_serial_t) arg5); | |
1673 | ||
1674 | case KEYCTL_READ: | |
1675 | return keyctl_read_key((key_serial_t) arg2, | |
1676 | (char __user *) arg3, | |
1677 | (size_t) arg4); | |
1678 | ||
1679 | case KEYCTL_CHOWN: | |
1680 | return keyctl_chown_key((key_serial_t) arg2, | |
1681 | (uid_t) arg3, | |
1682 | (gid_t) arg4); | |
1683 | ||
1684 | case KEYCTL_SETPERM: | |
1685 | return keyctl_setperm_key((key_serial_t) arg2, | |
1686 | (key_perm_t) arg3); | |
1687 | ||
1688 | case KEYCTL_INSTANTIATE: | |
1689 | return keyctl_instantiate_key((key_serial_t) arg2, | |
1690 | (const void __user *) arg3, | |
1691 | (size_t) arg4, | |
1692 | (key_serial_t) arg5); | |
1693 | ||
1694 | case KEYCTL_NEGATE: | |
1695 | return keyctl_negate_key((key_serial_t) arg2, | |
1696 | (unsigned) arg3, | |
1697 | (key_serial_t) arg4); | |
1698 | ||
3e30148c DH |
1699 | case KEYCTL_SET_REQKEY_KEYRING: |
1700 | return keyctl_set_reqkey_keyring(arg2); | |
1701 | ||
017679c4 DH |
1702 | case KEYCTL_SET_TIMEOUT: |
1703 | return keyctl_set_timeout((key_serial_t) arg2, | |
1704 | (unsigned) arg3); | |
1705 | ||
b5f545c8 DH |
1706 | case KEYCTL_ASSUME_AUTHORITY: |
1707 | return keyctl_assume_authority((key_serial_t) arg2); | |
1708 | ||
70a5bb72 DH |
1709 | case KEYCTL_GET_SECURITY: |
1710 | return keyctl_get_security((key_serial_t) arg2, | |
90bd49ab | 1711 | (char __user *) arg3, |
70a5bb72 DH |
1712 | (size_t) arg4); |
1713 | ||
ee18d64c DH |
1714 | case KEYCTL_SESSION_TO_PARENT: |
1715 | return keyctl_session_to_parent(); | |
1716 | ||
fdd1b945 DH |
1717 | case KEYCTL_REJECT: |
1718 | return keyctl_reject_key((key_serial_t) arg2, | |
1719 | (unsigned) arg3, | |
1720 | (unsigned) arg4, | |
1721 | (key_serial_t) arg5); | |
1722 | ||
ee009e4a DH |
1723 | case KEYCTL_INSTANTIATE_IOV: |
1724 | return keyctl_instantiate_key_iov( | |
1725 | (key_serial_t) arg2, | |
1726 | (const struct iovec __user *) arg3, | |
1727 | (unsigned) arg4, | |
1728 | (key_serial_t) arg5); | |
1729 | ||
fd75815f DH |
1730 | case KEYCTL_INVALIDATE: |
1731 | return keyctl_invalidate_key((key_serial_t) arg2); | |
1732 | ||
f36f8c75 DH |
1733 | case KEYCTL_GET_PERSISTENT: |
1734 | return keyctl_get_persistent((uid_t)arg2, (key_serial_t)arg3); | |
1735 | ||
ddbb4114 MM |
1736 | case KEYCTL_DH_COMPUTE: |
1737 | return keyctl_dh_compute((struct keyctl_dh_params __user *) arg2, | |
4693fc73 | 1738 | (char __user *) arg3, (size_t) arg4, |
f1c316a3 | 1739 | (struct keyctl_kdf_params __user *) arg5); |
ddbb4114 | 1740 | |
6563c91f MM |
1741 | case KEYCTL_RESTRICT_KEYRING: |
1742 | return keyctl_restrict_keyring((key_serial_t) arg2, | |
1743 | (const char __user *) arg3, | |
1744 | (const char __user *) arg4); | |
ddbb4114 | 1745 | |
1da177e4 LT |
1746 | default: |
1747 | return -EOPNOTSUPP; | |
1748 | } | |
a8b17ed0 | 1749 | } |