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1/* procfs files for key database enumeration
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>
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
21static int proc_keys_open(struct inode *inode, struct file *file);
22static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
23static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
24static void proc_keys_stop(struct seq_file *p, void *v);
25static int proc_keys_show(struct seq_file *m, void *v);
26
27static const struct seq_operations proc_keys_ops = {
28 .start = proc_keys_start,
29 .next = proc_keys_next,
30 .stop = proc_keys_stop,
31 .show = proc_keys_show,
32};
33
34static const struct file_operations proc_keys_fops = {
35 .open = proc_keys_open,
36 .read = seq_read,
37 .llseek = seq_lseek,
38 .release = seq_release,
39};
40
41static int proc_key_users_open(struct inode *inode, struct file *file);
42static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
43static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
44static void proc_key_users_stop(struct seq_file *p, void *v);
45static int proc_key_users_show(struct seq_file *m, void *v);
46
47static const struct seq_operations proc_key_users_ops = {
48 .start = proc_key_users_start,
49 .next = proc_key_users_next,
50 .stop = proc_key_users_stop,
51 .show = proc_key_users_show,
52};
53
54static const struct file_operations proc_key_users_fops = {
55 .open = proc_key_users_open,
56 .read = seq_read,
57 .llseek = seq_lseek,
58 .release = seq_release,
59};
60
61/*
62 * Declare the /proc files.
63 */
64static int __init key_proc_init(void)
65{
66 struct proc_dir_entry *p;
67
68 p = proc_create("keys", 0, NULL, &proc_keys_fops);
69 if (!p)
70 panic("Cannot create /proc/keys\n");
71
72 p = proc_create("key-users", 0, NULL, &proc_key_users_fops);
73 if (!p)
74 panic("Cannot create /proc/key-users\n");
75
76 return 0;
77}
78
79__initcall(key_proc_init);
80
81/*
82 * Implement "/proc/keys" to provide a list of the keys on the system that
83 * grant View permission to the caller.
84 */
85static struct rb_node *key_serial_next(struct seq_file *p, struct rb_node *n)
86{
87 struct user_namespace *user_ns = seq_user_ns(p);
88
89 n = rb_next(n);
90 while (n) {
91 struct key *key = rb_entry(n, struct key, serial_node);
92 if (kuid_has_mapping(user_ns, key->user->uid))
93 break;
94 n = rb_next(n);
95 }
96 return n;
97}
98
99static int proc_keys_open(struct inode *inode, struct file *file)
100{
101 return seq_open(file, &proc_keys_ops);
102}
103
104static struct key *find_ge_key(struct seq_file *p, key_serial_t id)
105{
106 struct user_namespace *user_ns = seq_user_ns(p);
107 struct rb_node *n = key_serial_tree.rb_node;
108 struct key *minkey = NULL;
109
110 while (n) {
111 struct key *key = rb_entry(n, struct key, serial_node);
112 if (id < key->serial) {
113 if (!minkey || minkey->serial > key->serial)
114 minkey = key;
115 n = n->rb_left;
116 } else if (id > key->serial) {
117 n = n->rb_right;
118 } else {
119 minkey = key;
120 break;
121 }
122 key = NULL;
123 }
124
125 if (!minkey)
126 return NULL;
127
128 for (;;) {
129 if (kuid_has_mapping(user_ns, minkey->user->uid))
130 return minkey;
131 n = rb_next(&minkey->serial_node);
132 if (!n)
133 return NULL;
134 minkey = rb_entry(n, struct key, serial_node);
135 }
136}
137
138static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
139 __acquires(key_serial_lock)
140{
141 key_serial_t pos = *_pos;
142 struct key *key;
143
144 spin_lock(&key_serial_lock);
145
146 if (*_pos > INT_MAX)
147 return NULL;
148 key = find_ge_key(p, pos);
149 if (!key)
150 return NULL;
151 *_pos = key->serial;
152 return &key->serial_node;
153}
154
155static inline key_serial_t key_node_serial(struct rb_node *n)
156{
157 struct key *key = rb_entry(n, struct key, serial_node);
158 return key->serial;
159}
160
161static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
162{
163 struct rb_node *n;
164
165 n = key_serial_next(p, v);
166 if (n)
167 *_pos = key_node_serial(n);
168 return n;
169}
170
171static void proc_keys_stop(struct seq_file *p, void *v)
172 __releases(key_serial_lock)
173{
174 spin_unlock(&key_serial_lock);
175}
176
177static int proc_keys_show(struct seq_file *m, void *v)
178{
179 struct rb_node *_p = v;
180 struct key *key = rb_entry(_p, struct key, serial_node);
181 struct timespec now;
182 unsigned long timo;
183 key_ref_t key_ref, skey_ref;
184 char xbuf[12];
185 int rc;
186
187 struct keyring_search_context ctx = {
188 .index_key.type = key->type,
189 .index_key.description = key->description,
190 .cred = current_cred(),
191 .match_data.cmp = lookup_user_key_possessed,
192 .match_data.raw_data = key,
193 .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
194 .flags = KEYRING_SEARCH_NO_STATE_CHECK,
195 };
196
197 key_ref = make_key_ref(key, 0);
198
199 /* determine if the key is possessed by this process (a test we can
200 * skip if the key does not indicate the possessor can view it
201 */
202 if (key->perm & KEY_POS_VIEW) {
203 skey_ref = search_my_process_keyrings(&ctx);
204 if (!IS_ERR(skey_ref)) {
205 key_ref_put(skey_ref);
206 key_ref = make_key_ref(key, 1);
207 }
208 }
209
210 /* check whether the current task is allowed to view the key (assuming
211 * non-possession)
212 * - the caller holds a spinlock, and thus the RCU read lock, making our
213 * access to __current_cred() safe
214 */
215 rc = key_task_permission(key_ref, ctx.cred, KEY_NEED_VIEW);
216 if (rc < 0)
217 return 0;
218
219 now = current_kernel_time();
220
221 rcu_read_lock();
222
223 /* come up with a suitable timeout value */
224 if (key->expiry == 0) {
225 memcpy(xbuf, "perm", 5);
226 } else if (now.tv_sec >= key->expiry) {
227 memcpy(xbuf, "expd", 5);
228 } else {
229 timo = key->expiry - now.tv_sec;
230
231 if (timo < 60)
232 sprintf(xbuf, "%lus", timo);
233 else if (timo < 60*60)
234 sprintf(xbuf, "%lum", timo / 60);
235 else if (timo < 60*60*24)
236 sprintf(xbuf, "%luh", timo / (60*60));
237 else if (timo < 60*60*24*7)
238 sprintf(xbuf, "%lud", timo / (60*60*24));
239 else
240 sprintf(xbuf, "%luw", timo / (60*60*24*7));
241 }
242
243#define showflag(KEY, LETTER, FLAG) \
244 (test_bit(FLAG, &(KEY)->flags) ? LETTER : '-')
245
246 seq_printf(m, "%08x %c%c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
247 key->serial,
248 showflag(key, 'I', KEY_FLAG_INSTANTIATED),
249 showflag(key, 'R', KEY_FLAG_REVOKED),
250 showflag(key, 'D', KEY_FLAG_DEAD),
251 showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
252 showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
253 showflag(key, 'N', KEY_FLAG_NEGATIVE),
254 showflag(key, 'i', KEY_FLAG_INVALIDATED),
255 atomic_read(&key->usage),
256 xbuf,
257 key->perm,
258 from_kuid_munged(seq_user_ns(m), key->uid),
259 from_kgid_munged(seq_user_ns(m), key->gid),
260 key->type->name);
261
262#undef showflag
263
264 if (key->type->describe)
265 key->type->describe(key, m);
266 seq_putc(m, '\n');
267
268 rcu_read_unlock();
269 return 0;
270}
271
272static struct rb_node *__key_user_next(struct user_namespace *user_ns, struct rb_node *n)
273{
274 while (n) {
275 struct key_user *user = rb_entry(n, struct key_user, node);
276 if (kuid_has_mapping(user_ns, user->uid))
277 break;
278 n = rb_next(n);
279 }
280 return n;
281}
282
283static struct rb_node *key_user_next(struct user_namespace *user_ns, struct rb_node *n)
284{
285 return __key_user_next(user_ns, rb_next(n));
286}
287
288static struct rb_node *key_user_first(struct user_namespace *user_ns, struct rb_root *r)
289{
290 struct rb_node *n = rb_first(r);
291 return __key_user_next(user_ns, n);
292}
293
294/*
295 * Implement "/proc/key-users" to provides a list of the key users and their
296 * quotas.
297 */
298static int proc_key_users_open(struct inode *inode, struct file *file)
299{
300 return seq_open(file, &proc_key_users_ops);
301}
302
303static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
304 __acquires(key_user_lock)
305{
306 struct rb_node *_p;
307 loff_t pos = *_pos;
308
309 spin_lock(&key_user_lock);
310
311 _p = key_user_first(seq_user_ns(p), &key_user_tree);
312 while (pos > 0 && _p) {
313 pos--;
314 _p = key_user_next(seq_user_ns(p), _p);
315 }
316
317 return _p;
318}
319
320static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
321{
322 (*_pos)++;
323 return key_user_next(seq_user_ns(p), (struct rb_node *)v);
324}
325
326static void proc_key_users_stop(struct seq_file *p, void *v)
327 __releases(key_user_lock)
328{
329 spin_unlock(&key_user_lock);
330}
331
332static int proc_key_users_show(struct seq_file *m, void *v)
333{
334 struct rb_node *_p = v;
335 struct key_user *user = rb_entry(_p, struct key_user, node);
336 unsigned maxkeys = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
337 key_quota_root_maxkeys : key_quota_maxkeys;
338 unsigned maxbytes = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
339 key_quota_root_maxbytes : key_quota_maxbytes;
340
341 seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
342 from_kuid_munged(seq_user_ns(m), user->uid),
343 atomic_read(&user->usage),
344 atomic_read(&user->nkeys),
345 atomic_read(&user->nikeys),
346 user->qnkeys,
347 maxkeys,
348 user->qnbytes,
349 maxbytes);
350
351 return 0;
352}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* procfs files for key database enumeration
3 *
4 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8#include <linux/init.h>
9#include <linux/sched.h>
10#include <linux/fs.h>
11#include <linux/proc_fs.h>
12#include <linux/seq_file.h>
13#include <asm/errno.h>
14#include "internal.h"
15
16static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
17static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
18static void proc_keys_stop(struct seq_file *p, void *v);
19static int proc_keys_show(struct seq_file *m, void *v);
20
21static const struct seq_operations proc_keys_ops = {
22 .start = proc_keys_start,
23 .next = proc_keys_next,
24 .stop = proc_keys_stop,
25 .show = proc_keys_show,
26};
27
28static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
29static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
30static void proc_key_users_stop(struct seq_file *p, void *v);
31static int proc_key_users_show(struct seq_file *m, void *v);
32
33static const struct seq_operations proc_key_users_ops = {
34 .start = proc_key_users_start,
35 .next = proc_key_users_next,
36 .stop = proc_key_users_stop,
37 .show = proc_key_users_show,
38};
39
40/*
41 * Declare the /proc files.
42 */
43static int __init key_proc_init(void)
44{
45 struct proc_dir_entry *p;
46
47 p = proc_create_seq("keys", 0, NULL, &proc_keys_ops);
48 if (!p)
49 panic("Cannot create /proc/keys\n");
50
51 p = proc_create_seq("key-users", 0, NULL, &proc_key_users_ops);
52 if (!p)
53 panic("Cannot create /proc/key-users\n");
54
55 return 0;
56}
57
58__initcall(key_proc_init);
59
60/*
61 * Implement "/proc/keys" to provide a list of the keys on the system that
62 * grant View permission to the caller.
63 */
64static struct rb_node *key_serial_next(struct seq_file *p, struct rb_node *n)
65{
66 struct user_namespace *user_ns = seq_user_ns(p);
67
68 n = rb_next(n);
69 while (n) {
70 struct key *key = rb_entry(n, struct key, serial_node);
71 if (kuid_has_mapping(user_ns, key->user->uid))
72 break;
73 n = rb_next(n);
74 }
75 return n;
76}
77
78static struct key *find_ge_key(struct seq_file *p, key_serial_t id)
79{
80 struct user_namespace *user_ns = seq_user_ns(p);
81 struct rb_node *n = key_serial_tree.rb_node;
82 struct key *minkey = NULL;
83
84 while (n) {
85 struct key *key = rb_entry(n, struct key, serial_node);
86 if (id < key->serial) {
87 if (!minkey || minkey->serial > key->serial)
88 minkey = key;
89 n = n->rb_left;
90 } else if (id > key->serial) {
91 n = n->rb_right;
92 } else {
93 minkey = key;
94 break;
95 }
96 key = NULL;
97 }
98
99 if (!minkey)
100 return NULL;
101
102 for (;;) {
103 if (kuid_has_mapping(user_ns, minkey->user->uid))
104 return minkey;
105 n = rb_next(&minkey->serial_node);
106 if (!n)
107 return NULL;
108 minkey = rb_entry(n, struct key, serial_node);
109 }
110}
111
112static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
113 __acquires(key_serial_lock)
114{
115 key_serial_t pos = *_pos;
116 struct key *key;
117
118 spin_lock(&key_serial_lock);
119
120 if (*_pos > INT_MAX)
121 return NULL;
122 key = find_ge_key(p, pos);
123 if (!key)
124 return NULL;
125 *_pos = key->serial;
126 return &key->serial_node;
127}
128
129static inline key_serial_t key_node_serial(struct rb_node *n)
130{
131 struct key *key = rb_entry(n, struct key, serial_node);
132 return key->serial;
133}
134
135static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
136{
137 struct rb_node *n;
138
139 n = key_serial_next(p, v);
140 if (n)
141 *_pos = key_node_serial(n);
142 return n;
143}
144
145static void proc_keys_stop(struct seq_file *p, void *v)
146 __releases(key_serial_lock)
147{
148 spin_unlock(&key_serial_lock);
149}
150
151static int proc_keys_show(struct seq_file *m, void *v)
152{
153 struct rb_node *_p = v;
154 struct key *key = rb_entry(_p, struct key, serial_node);
155 unsigned long flags;
156 key_ref_t key_ref, skey_ref;
157 time64_t now, expiry;
158 char xbuf[16];
159 short state;
160 u64 timo;
161 int rc;
162
163 struct keyring_search_context ctx = {
164 .index_key = key->index_key,
165 .cred = m->file->f_cred,
166 .match_data.cmp = lookup_user_key_possessed,
167 .match_data.raw_data = key,
168 .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
169 .flags = (KEYRING_SEARCH_NO_STATE_CHECK |
170 KEYRING_SEARCH_RECURSE),
171 };
172
173 key_ref = make_key_ref(key, 0);
174
175 /* determine if the key is possessed by this process (a test we can
176 * skip if the key does not indicate the possessor can view it
177 */
178 if (key->perm & KEY_POS_VIEW) {
179 rcu_read_lock();
180 skey_ref = search_cred_keyrings_rcu(&ctx);
181 rcu_read_unlock();
182 if (!IS_ERR(skey_ref)) {
183 key_ref_put(skey_ref);
184 key_ref = make_key_ref(key, 1);
185 }
186 }
187
188 /* check whether the current task is allowed to view the key */
189 rc = key_task_permission(key_ref, ctx.cred, KEY_NEED_VIEW);
190 if (rc < 0)
191 return 0;
192
193 now = ktime_get_real_seconds();
194
195 rcu_read_lock();
196
197 /* come up with a suitable timeout value */
198 expiry = READ_ONCE(key->expiry);
199 if (expiry == 0) {
200 memcpy(xbuf, "perm", 5);
201 } else if (now >= expiry) {
202 memcpy(xbuf, "expd", 5);
203 } else {
204 timo = expiry - now;
205
206 if (timo < 60)
207 sprintf(xbuf, "%llus", timo);
208 else if (timo < 60*60)
209 sprintf(xbuf, "%llum", div_u64(timo, 60));
210 else if (timo < 60*60*24)
211 sprintf(xbuf, "%lluh", div_u64(timo, 60 * 60));
212 else if (timo < 60*60*24*7)
213 sprintf(xbuf, "%llud", div_u64(timo, 60 * 60 * 24));
214 else
215 sprintf(xbuf, "%lluw", div_u64(timo, 60 * 60 * 24 * 7));
216 }
217
218 state = key_read_state(key);
219
220#define showflag(FLAGS, LETTER, FLAG) \
221 ((FLAGS & (1 << FLAG)) ? LETTER : '-')
222
223 flags = READ_ONCE(key->flags);
224 seq_printf(m, "%08x %c%c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
225 key->serial,
226 state != KEY_IS_UNINSTANTIATED ? 'I' : '-',
227 showflag(flags, 'R', KEY_FLAG_REVOKED),
228 showflag(flags, 'D', KEY_FLAG_DEAD),
229 showflag(flags, 'Q', KEY_FLAG_IN_QUOTA),
230 showflag(flags, 'U', KEY_FLAG_USER_CONSTRUCT),
231 state < 0 ? 'N' : '-',
232 showflag(flags, 'i', KEY_FLAG_INVALIDATED),
233 refcount_read(&key->usage),
234 xbuf,
235 key->perm,
236 from_kuid_munged(seq_user_ns(m), key->uid),
237 from_kgid_munged(seq_user_ns(m), key->gid),
238 key->type->name);
239
240#undef showflag
241
242 if (key->type->describe)
243 key->type->describe(key, m);
244 seq_putc(m, '\n');
245
246 rcu_read_unlock();
247 return 0;
248}
249
250static struct rb_node *__key_user_next(struct user_namespace *user_ns, struct rb_node *n)
251{
252 while (n) {
253 struct key_user *user = rb_entry(n, struct key_user, node);
254 if (kuid_has_mapping(user_ns, user->uid))
255 break;
256 n = rb_next(n);
257 }
258 return n;
259}
260
261static struct rb_node *key_user_next(struct user_namespace *user_ns, struct rb_node *n)
262{
263 return __key_user_next(user_ns, rb_next(n));
264}
265
266static struct rb_node *key_user_first(struct user_namespace *user_ns, struct rb_root *r)
267{
268 struct rb_node *n = rb_first(r);
269 return __key_user_next(user_ns, n);
270}
271
272static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
273 __acquires(key_user_lock)
274{
275 struct rb_node *_p;
276 loff_t pos = *_pos;
277
278 spin_lock(&key_user_lock);
279
280 _p = key_user_first(seq_user_ns(p), &key_user_tree);
281 while (pos > 0 && _p) {
282 pos--;
283 _p = key_user_next(seq_user_ns(p), _p);
284 }
285
286 return _p;
287}
288
289static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
290{
291 (*_pos)++;
292 return key_user_next(seq_user_ns(p), (struct rb_node *)v);
293}
294
295static void proc_key_users_stop(struct seq_file *p, void *v)
296 __releases(key_user_lock)
297{
298 spin_unlock(&key_user_lock);
299}
300
301static int proc_key_users_show(struct seq_file *m, void *v)
302{
303 struct rb_node *_p = v;
304 struct key_user *user = rb_entry(_p, struct key_user, node);
305 unsigned maxkeys = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
306 key_quota_root_maxkeys : key_quota_maxkeys;
307 unsigned maxbytes = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
308 key_quota_root_maxbytes : key_quota_maxbytes;
309
310 seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
311 from_kuid_munged(seq_user_ns(m), user->uid),
312 refcount_read(&user->usage),
313 atomic_read(&user->nkeys),
314 atomic_read(&user->nikeys),
315 user->qnkeys,
316 maxkeys,
317 user->qnbytes,
318 maxbytes);
319
320 return 0;
321}