Merge tag 'v3.10.56' into update
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / security / keys / proc.c
CommitLineData
973c9f4f 1/* procfs files for key database enumeration
1da177e4
LT
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
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>
1da177e4
LT
15#include <linux/fs.h>
16#include <linux/proc_fs.h>
17#include <linux/seq_file.h>
18#include <asm/errno.h>
19#include "internal.h"
20
21#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
22static int proc_keys_open(struct inode *inode, struct file *file);
23static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
24static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
25static void proc_keys_stop(struct seq_file *p, void *v);
26static int proc_keys_show(struct seq_file *m, void *v);
27
1996a109 28static const struct seq_operations proc_keys_ops = {
1da177e4
LT
29 .start = proc_keys_start,
30 .next = proc_keys_next,
31 .stop = proc_keys_stop,
32 .show = proc_keys_show,
33};
34
9c2e08c5 35static const struct file_operations proc_keys_fops = {
1da177e4
LT
36 .open = proc_keys_open,
37 .read = seq_read,
38 .llseek = seq_lseek,
39 .release = seq_release,
40};
41#endif
42
43static int proc_key_users_open(struct inode *inode, struct file *file);
44static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
45static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
46static void proc_key_users_stop(struct seq_file *p, void *v);
47static int proc_key_users_show(struct seq_file *m, void *v);
48
1996a109 49static const struct seq_operations proc_key_users_ops = {
1da177e4
LT
50 .start = proc_key_users_start,
51 .next = proc_key_users_next,
52 .stop = proc_key_users_stop,
53 .show = proc_key_users_show,
54};
55
9c2e08c5 56static const struct file_operations proc_key_users_fops = {
1da177e4
LT
57 .open = proc_key_users_open,
58 .read = seq_read,
59 .llseek = seq_lseek,
60 .release = seq_release,
61};
62
1da177e4 63/*
973c9f4f 64 * Declare the /proc files.
1da177e4
LT
65 */
66static int __init key_proc_init(void)
67{
68 struct proc_dir_entry *p;
69
70#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
da91d2ef 71 p = proc_create("keys", 0, NULL, &proc_keys_fops);
1da177e4
LT
72 if (!p)
73 panic("Cannot create /proc/keys\n");
1da177e4
LT
74#endif
75
da91d2ef 76 p = proc_create("key-users", 0, NULL, &proc_key_users_fops);
1da177e4
LT
77 if (!p)
78 panic("Cannot create /proc/key-users\n");
79
1da177e4 80 return 0;
a8b17ed0 81}
1da177e4
LT
82
83__initcall(key_proc_init);
84
1da177e4 85/*
973c9f4f
DH
86 * Implement "/proc/keys" to provide a list of the keys on the system that
87 * grant View permission to the caller.
1da177e4
LT
88 */
89#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
90
9a56c2db 91static struct rb_node *key_serial_next(struct seq_file *p, struct rb_node *n)
454804ab 92{
9a56c2db 93 struct user_namespace *user_ns = seq_user_ns(p);
ad73a717
SH
94
95 n = rb_next(n);
454804ab
SH
96 while (n) {
97 struct key *key = rb_entry(n, struct key, serial_node);
9a56c2db 98 if (kuid_has_mapping(user_ns, key->user->uid))
454804ab
SH
99 break;
100 n = rb_next(n);
101 }
102 return n;
103}
104
ad73a717 105static int proc_keys_open(struct inode *inode, struct file *file)
454804ab 106{
ad73a717 107 return seq_open(file, &proc_keys_ops);
454804ab
SH
108}
109
9a56c2db 110static struct key *find_ge_key(struct seq_file *p, key_serial_t id)
454804ab 111{
9a56c2db 112 struct user_namespace *user_ns = seq_user_ns(p);
ad73a717
SH
113 struct rb_node *n = key_serial_tree.rb_node;
114 struct key *minkey = NULL;
454804ab 115
ad73a717
SH
116 while (n) {
117 struct key *key = rb_entry(n, struct key, serial_node);
118 if (id < key->serial) {
119 if (!minkey || minkey->serial > key->serial)
120 minkey = key;
121 n = n->rb_left;
122 } else if (id > key->serial) {
123 n = n->rb_right;
124 } else {
125 minkey = key;
126 break;
127 }
128 key = NULL;
129 }
1da177e4 130
ad73a717
SH
131 if (!minkey)
132 return NULL;
133
134 for (;;) {
9a56c2db 135 if (kuid_has_mapping(user_ns, minkey->user->uid))
ad73a717
SH
136 return minkey;
137 n = rb_next(&minkey->serial_node);
138 if (!n)
139 return NULL;
140 minkey = rb_entry(n, struct key, serial_node);
141 }
1da177e4
LT
142}
143
144static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
86abcf9c 145 __acquires(key_serial_lock)
1da177e4 146{
ad73a717
SH
147 key_serial_t pos = *_pos;
148 struct key *key;
1da177e4
LT
149
150 spin_lock(&key_serial_lock);
151
ad73a717
SH
152 if (*_pos > INT_MAX)
153 return NULL;
9a56c2db 154 key = find_ge_key(p, pos);
ad73a717
SH
155 if (!key)
156 return NULL;
157 *_pos = key->serial;
158 return &key->serial_node;
159}
1da177e4 160
ad73a717
SH
161static inline key_serial_t key_node_serial(struct rb_node *n)
162{
163 struct key *key = rb_entry(n, struct key, serial_node);
164 return key->serial;
1da177e4
LT
165}
166
167static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
168{
ad73a717 169 struct rb_node *n;
1da177e4 170
9a56c2db 171 n = key_serial_next(p, v);
ad73a717
SH
172 if (n)
173 *_pos = key_node_serial(n);
174 return n;
1da177e4
LT
175}
176
177static void proc_keys_stop(struct seq_file *p, void *v)
86abcf9c 178 __releases(key_serial_lock)
1da177e4
LT
179{
180 spin_unlock(&key_serial_lock);
181}
182
183static int proc_keys_show(struct seq_file *m, void *v)
184{
927942aa 185 const struct cred *cred = current_cred();
1da177e4
LT
186 struct rb_node *_p = v;
187 struct key *key = rb_entry(_p, struct key, serial_node);
188 struct timespec now;
189 unsigned long timo;
927942aa 190 key_ref_t key_ref, skey_ref;
1da177e4 191 char xbuf[12];
06ec7be5
ML
192 int rc;
193
927942aa
DH
194 key_ref = make_key_ref(key, 0);
195
196 /* determine if the key is possessed by this process (a test we can
197 * skip if the key does not indicate the possessor can view it
198 */
199 if (key->perm & KEY_POS_VIEW) {
200 skey_ref = search_my_process_keyrings(key->type, key,
201 lookup_user_key_possessed,
78b7280c 202 true, cred);
927942aa
DH
203 if (!IS_ERR(skey_ref)) {
204 key_ref_put(skey_ref);
205 key_ref = make_key_ref(key, 1);
206 }
207 }
208
06ec7be5 209 /* check whether the current task is allowed to view the key (assuming
d84f4f99
DH
210 * non-possession)
211 * - the caller holds a spinlock, and thus the RCU read lock, making our
212 * access to __current_cred() safe
213 */
927942aa 214 rc = key_task_permission(key_ref, cred, KEY_VIEW);
06ec7be5
ML
215 if (rc < 0)
216 return 0;
1da177e4
LT
217
218 now = current_kernel_time();
219
76d8aeab 220 rcu_read_lock();
1da177e4
LT
221
222 /* come up with a suitable timeout value */
223 if (key->expiry == 0) {
224 memcpy(xbuf, "perm", 5);
7b1b9164 225 } else if (now.tv_sec >= key->expiry) {
1da177e4 226 memcpy(xbuf, "expd", 5);
7b1b9164 227 } else {
1da177e4
LT
228 timo = key->expiry - now.tv_sec;
229
230 if (timo < 60)
231 sprintf(xbuf, "%lus", timo);
232 else if (timo < 60*60)
233 sprintf(xbuf, "%lum", timo / 60);
234 else if (timo < 60*60*24)
235 sprintf(xbuf, "%luh", timo / (60*60));
236 else if (timo < 60*60*24*7)
237 sprintf(xbuf, "%lud", timo / (60*60*24));
238 else
239 sprintf(xbuf, "%luw", timo / (60*60*24*7));
240 }
241
76d8aeab
DH
242#define showflag(KEY, LETTER, FLAG) \
243 (test_bit(FLAG, &(KEY)->flags) ? LETTER : '-')
244
fd75815f 245 seq_printf(m, "%08x %c%c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
1da177e4 246 key->serial,
76d8aeab
DH
247 showflag(key, 'I', KEY_FLAG_INSTANTIATED),
248 showflag(key, 'R', KEY_FLAG_REVOKED),
249 showflag(key, 'D', KEY_FLAG_DEAD),
250 showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
251 showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
252 showflag(key, 'N', KEY_FLAG_NEGATIVE),
fd75815f 253 showflag(key, 'i', KEY_FLAG_INVALIDATED),
1da177e4
LT
254 atomic_read(&key->usage),
255 xbuf,
256 key->perm,
9a56c2db
EB
257 from_kuid_munged(seq_user_ns(m), key->uid),
258 from_kgid_munged(seq_user_ns(m), key->gid),
1da177e4
LT
259 key->type->name);
260
76d8aeab
DH
261#undef showflag
262
1da177e4
LT
263 if (key->type->describe)
264 key->type->describe(key, m);
265 seq_putc(m, '\n');
266
76d8aeab 267 rcu_read_unlock();
1da177e4 268 return 0;
1da177e4
LT
269}
270
271#endif /* CONFIG_KEYS_DEBUG_PROC_KEYS */
272
9a56c2db 273static struct rb_node *__key_user_next(struct user_namespace *user_ns, struct rb_node *n)
454804ab
SH
274{
275 while (n) {
276 struct key_user *user = rb_entry(n, struct key_user, node);
9a56c2db 277 if (kuid_has_mapping(user_ns, user->uid))
454804ab
SH
278 break;
279 n = rb_next(n);
280 }
281 return n;
282}
283
9a56c2db 284static struct rb_node *key_user_next(struct user_namespace *user_ns, struct rb_node *n)
454804ab 285{
9a56c2db 286 return __key_user_next(user_ns, rb_next(n));
454804ab
SH
287}
288
9a56c2db 289static struct rb_node *key_user_first(struct user_namespace *user_ns, struct rb_root *r)
454804ab
SH
290{
291 struct rb_node *n = rb_first(r);
9a56c2db 292 return __key_user_next(user_ns, n);
454804ab 293}
7b1b9164 294
1da177e4 295/*
973c9f4f
DH
296 * Implement "/proc/key-users" to provides a list of the key users and their
297 * quotas.
1da177e4
LT
298 */
299static int proc_key_users_open(struct inode *inode, struct file *file)
300{
301 return seq_open(file, &proc_key_users_ops);
1da177e4
LT
302}
303
304static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
86abcf9c 305 __acquires(key_user_lock)
1da177e4
LT
306{
307 struct rb_node *_p;
308 loff_t pos = *_pos;
309
310 spin_lock(&key_user_lock);
311
9a56c2db 312 _p = key_user_first(seq_user_ns(p), &key_user_tree);
1da177e4
LT
313 while (pos > 0 && _p) {
314 pos--;
9a56c2db 315 _p = key_user_next(seq_user_ns(p), _p);
1da177e4
LT
316 }
317
318 return _p;
1da177e4
LT
319}
320
321static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
322{
323 (*_pos)++;
9a56c2db 324 return key_user_next(seq_user_ns(p), (struct rb_node *)v);
1da177e4
LT
325}
326
327static void proc_key_users_stop(struct seq_file *p, void *v)
86abcf9c 328 __releases(key_user_lock)
1da177e4
LT
329{
330 spin_unlock(&key_user_lock);
331}
332
333static int proc_key_users_show(struct seq_file *m, void *v)
334{
335 struct rb_node *_p = v;
336 struct key_user *user = rb_entry(_p, struct key_user, node);
9a56c2db 337 unsigned maxkeys = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
0b77f5bf 338 key_quota_root_maxkeys : key_quota_maxkeys;
9a56c2db 339 unsigned maxbytes = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
0b77f5bf 340 key_quota_root_maxbytes : key_quota_maxbytes;
1da177e4
LT
341
342 seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
9a56c2db 343 from_kuid_munged(seq_user_ns(m), user->uid),
1da177e4
LT
344 atomic_read(&user->usage),
345 atomic_read(&user->nkeys),
346 atomic_read(&user->nikeys),
347 user->qnkeys,
0b77f5bf 348 maxkeys,
1da177e4 349 user->qnbytes,
0b77f5bf 350 maxbytes);
1da177e4
LT
351
352 return 0;
1da177e4 353}