Linux Audio

Check our new training course

Loading...
v5.9
  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	else
143		(*_pos)++;
144	return n;
145}
146
147static void proc_keys_stop(struct seq_file *p, void *v)
148	__releases(key_serial_lock)
149{
150	spin_unlock(&key_serial_lock);
151}
152
153static int proc_keys_show(struct seq_file *m, void *v)
154{
155	struct rb_node *_p = v;
156	struct key *key = rb_entry(_p, struct key, serial_node);
157	unsigned long flags;
158	key_ref_t key_ref, skey_ref;
159	time64_t now, expiry;
160	char xbuf[16];
161	short state;
162	u64 timo;
163	int rc;
164
165	struct keyring_search_context ctx = {
166		.index_key		= key->index_key,
167		.cred			= m->file->f_cred,
168		.match_data.cmp		= lookup_user_key_possessed,
169		.match_data.raw_data	= key,
170		.match_data.lookup_type	= KEYRING_SEARCH_LOOKUP_DIRECT,
171		.flags			= (KEYRING_SEARCH_NO_STATE_CHECK |
172					   KEYRING_SEARCH_RECURSE),
173	};
174
175	key_ref = make_key_ref(key, 0);
176
177	/* determine if the key is possessed by this process (a test we can
178	 * skip if the key does not indicate the possessor can view it
179	 */
180	if (key->perm & KEY_POS_VIEW) {
181		rcu_read_lock();
182		skey_ref = search_cred_keyrings_rcu(&ctx);
183		rcu_read_unlock();
184		if (!IS_ERR(skey_ref)) {
185			key_ref_put(skey_ref);
186			key_ref = make_key_ref(key, 1);
187		}
188	}
189
190	/* check whether the current task is allowed to view the key */
191	rc = key_task_permission(key_ref, ctx.cred, KEY_NEED_VIEW);
192	if (rc < 0)
193		return 0;
194
195	now = ktime_get_real_seconds();
196
197	rcu_read_lock();
198
199	/* come up with a suitable timeout value */
200	expiry = READ_ONCE(key->expiry);
201	if (expiry == 0) {
202		memcpy(xbuf, "perm", 5);
203	} else if (now >= expiry) {
204		memcpy(xbuf, "expd", 5);
205	} else {
206		timo = expiry - now;
207
208		if (timo < 60)
209			sprintf(xbuf, "%llus", timo);
210		else if (timo < 60*60)
211			sprintf(xbuf, "%llum", div_u64(timo, 60));
212		else if (timo < 60*60*24)
213			sprintf(xbuf, "%lluh", div_u64(timo, 60 * 60));
214		else if (timo < 60*60*24*7)
215			sprintf(xbuf, "%llud", div_u64(timo, 60 * 60 * 24));
216		else
217			sprintf(xbuf, "%lluw", div_u64(timo, 60 * 60 * 24 * 7));
218	}
219
220	state = key_read_state(key);
221
222#define showflag(FLAGS, LETTER, FLAG) \
223	((FLAGS & (1 << FLAG)) ? LETTER : '-')
224
225	flags = READ_ONCE(key->flags);
226	seq_printf(m, "%08x %c%c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
227		   key->serial,
228		   state != KEY_IS_UNINSTANTIATED ? 'I' : '-',
229		   showflag(flags, 'R', KEY_FLAG_REVOKED),
230		   showflag(flags, 'D', KEY_FLAG_DEAD),
231		   showflag(flags, 'Q', KEY_FLAG_IN_QUOTA),
232		   showflag(flags, 'U', KEY_FLAG_USER_CONSTRUCT),
233		   state < 0 ? 'N' : '-',
234		   showflag(flags, 'i', KEY_FLAG_INVALIDATED),
235		   refcount_read(&key->usage),
236		   xbuf,
237		   key->perm,
238		   from_kuid_munged(seq_user_ns(m), key->uid),
239		   from_kgid_munged(seq_user_ns(m), key->gid),
240		   key->type->name);
241
242#undef showflag
243
244	if (key->type->describe)
245		key->type->describe(key, m);
246	seq_putc(m, '\n');
247
248	rcu_read_unlock();
249	return 0;
250}
251
252static struct rb_node *__key_user_next(struct user_namespace *user_ns, struct rb_node *n)
253{
254	while (n) {
255		struct key_user *user = rb_entry(n, struct key_user, node);
256		if (kuid_has_mapping(user_ns, user->uid))
257			break;
258		n = rb_next(n);
259	}
260	return n;
261}
262
263static struct rb_node *key_user_next(struct user_namespace *user_ns, struct rb_node *n)
264{
265	return __key_user_next(user_ns, rb_next(n));
266}
267
268static struct rb_node *key_user_first(struct user_namespace *user_ns, struct rb_root *r)
269{
270	struct rb_node *n = rb_first(r);
271	return __key_user_next(user_ns, n);
272}
273
274static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
275	__acquires(key_user_lock)
276{
277	struct rb_node *_p;
278	loff_t pos = *_pos;
279
280	spin_lock(&key_user_lock);
281
282	_p = key_user_first(seq_user_ns(p), &key_user_tree);
283	while (pos > 0 && _p) {
284		pos--;
285		_p = key_user_next(seq_user_ns(p), _p);
286	}
287
288	return _p;
289}
290
291static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
292{
293	(*_pos)++;
294	return key_user_next(seq_user_ns(p), (struct rb_node *)v);
295}
296
297static void proc_key_users_stop(struct seq_file *p, void *v)
298	__releases(key_user_lock)
299{
300	spin_unlock(&key_user_lock);
301}
302
303static int proc_key_users_show(struct seq_file *m, void *v)
304{
305	struct rb_node *_p = v;
306	struct key_user *user = rb_entry(_p, struct key_user, node);
307	unsigned maxkeys = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
308		key_quota_root_maxkeys : key_quota_maxkeys;
309	unsigned maxbytes = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
310		key_quota_root_maxbytes : key_quota_maxbytes;
311
312	seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
313		   from_kuid_munged(seq_user_ns(m), user->uid),
314		   refcount_read(&user->usage),
315		   atomic_read(&user->nkeys),
316		   atomic_read(&user->nikeys),
317		   user->qnkeys,
318		   maxkeys,
319		   user->qnbytes,
320		   maxbytes);
321
322	return 0;
323}
v5.4
  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}