[deliverable/linux.git] / security / keys / proc.c

/* proc.c: proc files for key database enumeration
 *
 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <asm/errno.h>
#include "internal.h"

#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
static int proc_keys_open(struct inode *inode, struct file *file);
static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
static void proc_keys_stop(struct seq_file *p, void *v);
static int proc_keys_show(struct seq_file *m, void *v);

static const struct seq_operations proc_keys_ops = {
	.start	= proc_keys_start,
	.next	= proc_keys_next,
	.stop	= proc_keys_stop,
	.show	= proc_keys_show,
};

static const struct file_operations proc_keys_fops = {
	.open		= proc_keys_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};
#endif

static int proc_key_users_open(struct inode *inode, struct file *file);
static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
static void proc_key_users_stop(struct seq_file *p, void *v);
static int proc_key_users_show(struct seq_file *m, void *v);

static const struct seq_operations proc_key_users_ops = {
	.start	= proc_key_users_start,
	.next	= proc_key_users_next,
	.stop	= proc_key_users_stop,
	.show	= proc_key_users_show,
};

static const struct file_operations proc_key_users_fops = {
	.open		= proc_key_users_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

/*
 * declare the /proc files
 */
static int __init key_proc_init(void)
{
	struct proc_dir_entry *p;

#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
	p = proc_create("keys", 0, NULL, &proc_keys_fops);
	if (!p)
		panic("Cannot create /proc/keys\n");
#endif

	p = proc_create("key-users", 0, NULL, &proc_key_users_fops);
	if (!p)
		panic("Cannot create /proc/key-users\n");

	return 0;
}

__initcall(key_proc_init);

/*
 * implement "/proc/keys" to provides a list of the keys on the system
 */
#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS

static struct rb_node *key_serial_next(struct rb_node *n)
{
	struct user_namespace *user_ns = current_user_ns();

	n = rb_next(n);
	while (n) {
		struct key *key = rb_entry(n, struct key, serial_node);
		if (key->user->user_ns == user_ns)
			break;
		n = rb_next(n);
	}
	return n;
}

static int proc_keys_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &proc_keys_ops);
}

static struct key *find_ge_key(key_serial_t id)
{
	struct user_namespace *user_ns = current_user_ns();
	struct rb_node *n = key_serial_tree.rb_node;
	struct key *minkey = NULL;

	while (n) {
		struct key *key = rb_entry(n, struct key, serial_node);
		if (id < key->serial) {
			if (!minkey || minkey->serial > key->serial)
				minkey = key;
			n = n->rb_left;
		} else if (id > key->serial) {
			n = n->rb_right;
		} else {
			minkey = key;
			break;
		}
		key = NULL;
	}

	if (!minkey)
		return NULL;

	for (;;) {
		if (minkey->user->user_ns == user_ns)
			return minkey;
		n = rb_next(&minkey->serial_node);
		if (!n)
			return NULL;
		minkey = rb_entry(n, struct key, serial_node);
	}
}

static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
	__acquires(key_serial_lock)
{
	key_serial_t pos = *_pos;
	struct key *key;

	spin_lock(&key_serial_lock);

	if (*_pos > INT_MAX)
		return NULL;
	key = find_ge_key(pos);
	if (!key)
		return NULL;
	*_pos = key->serial;
	return &key->serial_node;
}

static inline key_serial_t key_node_serial(struct rb_node *n)
{
	struct key *key = rb_entry(n, struct key, serial_node);
	return key->serial;
}

static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
{
	struct rb_node *n;

	n = key_serial_next(v);
	if (n)
		*_pos = key_node_serial(n);
	return n;
}

static void proc_keys_stop(struct seq_file *p, void *v)
	__releases(key_serial_lock)
{
	spin_unlock(&key_serial_lock);
}

static int proc_keys_show(struct seq_file *m, void *v)
{
	const struct cred *cred = current_cred();
	struct rb_node *_p = v;
	struct key *key = rb_entry(_p, struct key, serial_node);
	struct timespec now;
	unsigned long timo;
	key_ref_t key_ref, skey_ref;
	char xbuf[12];
	int rc;

	key_ref = make_key_ref(key, 0);

	/* determine if the key is possessed by this process (a test we can
	 * skip if the key does not indicate the possessor can view it
	 */
	if (key->perm & KEY_POS_VIEW) {
		skey_ref = search_my_process_keyrings(key->type, key,
						      lookup_user_key_possessed,
						      cred);
		if (!IS_ERR(skey_ref)) {
			key_ref_put(skey_ref);
			key_ref = make_key_ref(key, 1);
		}
	}

	/* check whether the current task is allowed to view the key (assuming
	 * non-possession)
	 * - the caller holds a spinlock, and thus the RCU read lock, making our
	 *   access to __current_cred() safe
	 */
	rc = key_task_permission(key_ref, cred, KEY_VIEW);
	if (rc < 0)
		return 0;

	now = current_kernel_time();

	rcu_read_lock();

	/* come up with a suitable timeout value */
	if (key->expiry == 0) {
		memcpy(xbuf, "perm", 5);
	} else if (now.tv_sec >= key->expiry) {
		memcpy(xbuf, "expd", 5);
	} else {
		timo = key->expiry - now.tv_sec;

		if (timo < 60)
			sprintf(xbuf, "%lus", timo);
		else if (timo < 60*60)
			sprintf(xbuf, "%lum", timo / 60);
		else if (timo < 60*60*24)
			sprintf(xbuf, "%luh", timo / (60*60));
		else if (timo < 60*60*24*7)
			sprintf(xbuf, "%lud", timo / (60*60*24));
		else
			sprintf(xbuf, "%luw", timo / (60*60*24*7));
	}

#define showflag(KEY, LETTER, FLAG) \
	(test_bit(FLAG,	&(KEY)->flags) ? LETTER : '-')

	seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
		   key->serial,
		   showflag(key, 'I', KEY_FLAG_INSTANTIATED),
		   showflag(key, 'R', KEY_FLAG_REVOKED),
		   showflag(key, 'D', KEY_FLAG_DEAD),
		   showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
		   showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
		   showflag(key, 'N', KEY_FLAG_NEGATIVE),
		   atomic_read(&key->usage),
		   xbuf,
		   key->perm,
		   key->uid,
		   key->gid,
		   key->type->name);

#undef showflag

	if (key->type->describe)
		key->type->describe(key, m);
	seq_putc(m, '\n');

	rcu_read_unlock();
	return 0;
}

#endif /* CONFIG_KEYS_DEBUG_PROC_KEYS */

static struct rb_node *__key_user_next(struct rb_node *n)
{
	while (n) {
		struct key_user *user = rb_entry(n, struct key_user, node);
		if (user->user_ns == current_user_ns())
			break;
		n = rb_next(n);
	}
	return n;
}

static struct rb_node *key_user_next(struct rb_node *n)
{
	return __key_user_next(rb_next(n));
}

static struct rb_node *key_user_first(struct rb_root *r)
{
	struct rb_node *n = rb_first(r);
	return __key_user_next(n);
}

/*
 * implement "/proc/key-users" to provides a list of the key users
 */
static int proc_key_users_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &proc_key_users_ops);
}

static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
	__acquires(key_user_lock)
{
	struct rb_node *_p;
	loff_t pos = *_pos;

	spin_lock(&key_user_lock);

	_p = key_user_first(&key_user_tree);
	while (pos > 0 && _p) {
		pos--;
		_p = key_user_next(_p);
	}

	return _p;
}

static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
{
	(*_pos)++;
	return key_user_next((struct rb_node *)v);
}

static void proc_key_users_stop(struct seq_file *p, void *v)
	__releases(key_user_lock)
{
	spin_unlock(&key_user_lock);
}

static int proc_key_users_show(struct seq_file *m, void *v)
{
	struct rb_node *_p = v;
	struct key_user *user = rb_entry(_p, struct key_user, node);
	unsigned maxkeys = (user->uid == 0) ?
		key_quota_root_maxkeys : key_quota_maxkeys;
	unsigned maxbytes = (user->uid == 0) ?
		key_quota_root_maxbytes : key_quota_maxbytes;

	seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
		   user->uid,
		   atomic_read(&user->usage),
		   atomic_read(&user->nkeys),
		   atomic_read(&user->nikeys),
		   user->qnkeys,
		   maxkeys,
		   user->qnbytes,
		   maxbytes);

	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/* proc.c: proc 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>
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
	22	static int proc_keys_open(struct inode inode, struct file file);
	23	static void proc_keys_start(struct seq_file p, loff_t *_pos);
	24	static void proc_keys_next(struct seq_file p, void v, loff_t _pos);
	25	static void proc_keys_stop(struct seq_file p, void v);
	26	static int proc_keys_show(struct seq_file m, void v);
	27
1996a109	28	static 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	35	static 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
	43	static int proc_key_users_open(struct inode inode, struct file file);
	44	static void proc_key_users_start(struct seq_file p, loff_t *_pos);
	45	static void proc_key_users_next(struct seq_file p, void v, loff_t _pos);
	46	static void proc_key_users_stop(struct seq_file p, void v);
	47	static int proc_key_users_show(struct seq_file m, void v);
	48
1996a109	49	static 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	56	static 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 LT	63	/*
	64	* declare the /proc files
	65	*/
	66	static 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)
1da177e4 LT	73	panic("Cannot create /proc/keys\n");
1da177e4 LT	74	#endif
1da177e4 LT	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 LT	85	/*
	86	* implement "/proc/keys" to provides a list of the keys on the system
	87	*/
	88	#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
	89
ad73a717	90	static struct rb_node key_serial_next(struct rb_node n)
454804ab	91	{
ad73a717 SH	92	struct user_namespace *user_ns = current_user_ns();
	93
	94	n = rb_next(n);
454804ab SH	95	while (n) {
454804ab SH	96	struct key *key = rb_entry(n, struct key, serial_node);
ad73a717	97	if (key->user->user_ns == user_ns)
454804ab SH	98	break;
	99	n = rb_next(n);
	100	}
	101	return n;
	102	}
	103
ad73a717	104	static int proc_keys_open(struct inode inode, struct file file)
454804ab	105	{
ad73a717	106	return seq_open(file, &proc_keys_ops);
454804ab SH	107	}
454804ab SH	108
ad73a717	109	static struct key *find_ge_key(key_serial_t id)
454804ab	110	{
ad73a717 SH	111	struct user_namespace *user_ns = current_user_ns();
	112	struct rb_node *n = key_serial_tree.rb_node;
	113	struct key *minkey = NULL;
454804ab	114
ad73a717 SH	115	while (n) {
	116	struct key *key = rb_entry(n, struct key, serial_node);
	117	if (id < key->serial) {
	118	if (!minkey \|\| minkey->serial > key->serial)
	119	minkey = key;
	120	n = n->rb_left;
	121	} else if (id > key->serial) {
	122	n = n->rb_right;
	123	} else {
	124	minkey = key;
	125	break;
	126	}
	127	key = NULL;
	128	}
1da177e4	129
ad73a717 SH	130	if (!minkey)
	131	return NULL;
	132
	133	for (;;) {
	134	if (minkey->user->user_ns == user_ns)
	135	return minkey;
	136	n = rb_next(&minkey->serial_node);
	137	if (!n)
	138	return NULL;
	139	minkey = rb_entry(n, struct key, serial_node);
	140	}
1da177e4 LT	141	}
	142
	143	static void proc_keys_start(struct seq_file p, loff_t *_pos)
86abcf9c	144	__acquires(key_serial_lock)
1da177e4	145	{
ad73a717 SH	146	key_serial_t pos = *_pos;
ad73a717 SH	147	struct key *key;
1da177e4 LT	148
	149	spin_lock(&key_serial_lock);
	150
ad73a717 SH	151	if (*_pos > INT_MAX)
	152	return NULL;
	153	key = find_ge_key(pos);
	154	if (!key)
	155	return NULL;
	156	*_pos = key->serial;
	157	return &key->serial_node;
	158	}
1da177e4	159
ad73a717 SH	160	static inline key_serial_t key_node_serial(struct rb_node *n)
	161	{
	162	struct key *key = rb_entry(n, struct key, serial_node);
	163	return key->serial;
1da177e4 LT	164	}
	165
	166	static void proc_keys_next(struct seq_file p, void v, loff_t _pos)
	167	{
ad73a717	168	struct rb_node *n;
1da177e4	169
ad73a717 SH	170	n = key_serial_next(v);
	171	if (n)
	172	*_pos = key_node_serial(n);
	173	return n;
1da177e4 LT	174	}
	175
	176	static void proc_keys_stop(struct seq_file p, void v)
86abcf9c	177	__releases(key_serial_lock)
1da177e4 LT	178	{
	179	spin_unlock(&key_serial_lock);
	180	}
	181
	182	static int proc_keys_show(struct seq_file m, void v)
	183	{
927942aa	184	const struct cred *cred = current_cred();
1da177e4 LT	185	struct rb_node *_p = v;
	186	struct key *key = rb_entry(_p, struct key, serial_node);
	187	struct timespec now;
	188	unsigned long timo;
927942aa	189	key_ref_t key_ref, skey_ref;
1da177e4	190	char xbuf[12];
06ec7be5 ML	191	int rc;
06ec7be5 ML	192
927942aa DH	193	key_ref = make_key_ref(key, 0);
	194
	195	/* determine if the key is possessed by this process (a test we can
	196	* skip if the key does not indicate the possessor can view it
	197	*/
	198	if (key->perm & KEY_POS_VIEW) {
	199	skey_ref = search_my_process_keyrings(key->type, key,
	200	lookup_user_key_possessed,
	201	cred);
	202	if (!IS_ERR(skey_ref)) {
	203	key_ref_put(skey_ref);
	204	key_ref = make_key_ref(key, 1);
	205	}
	206	}
	207
06ec7be5	208	/* check whether the current task is allowed to view the key (assuming
d84f4f99 DH	209	* non-possession)
	210	* - the caller holds a spinlock, and thus the RCU read lock, making our
	211	* access to __current_cred() safe
	212	*/
927942aa	213	rc = key_task_permission(key_ref, cred, KEY_VIEW);
06ec7be5 ML	214	if (rc < 0)
06ec7be5 ML	215	return 0;
1da177e4 LT	216
	217	now = current_kernel_time();
	218
76d8aeab	219	rcu_read_lock();
1da177e4 LT	220
	221	/* come up with a suitable timeout value */
	222	if (key->expiry == 0) {
	223	memcpy(xbuf, "perm", 5);
7b1b9164	224	} else if (now.tv_sec >= key->expiry) {
1da177e4	225	memcpy(xbuf, "expd", 5);
7b1b9164	226	} else {
1da177e4 LT	227	timo = key->expiry - now.tv_sec;
	228
	229	if (timo < 60)
	230	sprintf(xbuf, "%lus", timo);
	231	else if (timo < 60*60)
	232	sprintf(xbuf, "%lum", timo / 60);
	233	else if (timo < 606024)
	234	sprintf(xbuf, "%luh", timo / (60*60));
	235	else if (timo < 606024*7)
	236	sprintf(xbuf, "%lud", timo / (606024));
	237	else
	238	sprintf(xbuf, "%luw", timo / (606024*7));
	239	}
	240
76d8aeab DH	241	#define showflag(KEY, LETTER, FLAG) \
	242	(test_bit(FLAG, &(KEY)->flags) ? LETTER : '-')
	243
664cceb0	244	seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
1da177e4	245	key->serial,
76d8aeab DH	246	showflag(key, 'I', KEY_FLAG_INSTANTIATED),
	247	showflag(key, 'R', KEY_FLAG_REVOKED),
	248	showflag(key, 'D', KEY_FLAG_DEAD),
	249	showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
	250	showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
	251	showflag(key, 'N', KEY_FLAG_NEGATIVE),
1da177e4 LT	252	atomic_read(&key->usage),
	253	xbuf,
	254	key->perm,
	255	key->uid,
	256	key->gid,
	257	key->type->name);
	258
76d8aeab DH	259	#undef showflag
76d8aeab DH	260
1da177e4 LT	261	if (key->type->describe)
	262	key->type->describe(key, m);
	263	seq_putc(m, '\n');
	264
76d8aeab	265	rcu_read_unlock();
1da177e4	266	return 0;
1da177e4 LT	267	}
	268
	269	#endif /* CONFIG_KEYS_DEBUG_PROC_KEYS */
	270
454804ab SH	271	static struct rb_node __key_user_next(struct rb_node n)
	272	{
	273	while (n) {
	274	struct key_user *user = rb_entry(n, struct key_user, node);
	275	if (user->user_ns == current_user_ns())
	276	break;
	277	n = rb_next(n);
	278	}
	279	return n;
	280	}
	281
	282	static struct rb_node key_user_next(struct rb_node n)
	283	{
	284	return __key_user_next(rb_next(n));
	285	}
	286
	287	static struct rb_node key_user_first(struct rb_root r)
	288	{
	289	struct rb_node *n = rb_first(r);
	290	return __key_user_next(n);
	291	}
7b1b9164	292
1da177e4 LT	293	/*
	294	* implement "/proc/key-users" to provides a list of the key users
	295	*/
	296	static int proc_key_users_open(struct inode inode, struct file file)
	297	{
	298	return seq_open(file, &proc_key_users_ops);
1da177e4 LT	299	}
	300
	301	static void proc_key_users_start(struct seq_file p, loff_t *_pos)
86abcf9c	302	__acquires(key_user_lock)
1da177e4 LT	303	{
	304	struct rb_node *_p;
	305	loff_t pos = *_pos;
	306
	307	spin_lock(&key_user_lock);
	308
454804ab	309	_p = key_user_first(&key_user_tree);
1da177e4 LT	310	while (pos > 0 && _p) {
1da177e4 LT	311	pos--;
454804ab	312	_p = key_user_next(_p);
1da177e4 LT	313	}
	314
	315	return _p;
1da177e4 LT	316	}
	317
	318	static void proc_key_users_next(struct seq_file p, void v, loff_t _pos)
	319	{
	320	(*_pos)++;
c5b60b5e	321	return key_user_next((struct rb_node *)v);
1da177e4 LT	322	}
	323
	324	static void proc_key_users_stop(struct seq_file p, void v)
86abcf9c	325	__releases(key_user_lock)
1da177e4 LT	326	{
	327	spin_unlock(&key_user_lock);
	328	}
	329
	330	static int proc_key_users_show(struct seq_file m, void v)
	331	{
	332	struct rb_node *_p = v;
	333	struct key_user *user = rb_entry(_p, struct key_user, node);
0b77f5bf DH	334	unsigned maxkeys = (user->uid == 0) ?
	335	key_quota_root_maxkeys : key_quota_maxkeys;
	336	unsigned maxbytes = (user->uid == 0) ?
	337	key_quota_root_maxbytes : key_quota_maxbytes;
1da177e4 LT	338
	339	seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
	340	user->uid,
	341	atomic_read(&user->usage),
	342	atomic_read(&user->nkeys),
	343	atomic_read(&user->nikeys),
	344	user->qnkeys,
0b77f5bf	345	maxkeys,
1da177e4	346	user->qnbytes,
0b77f5bf	347	maxbytes);
1da177e4 LT	348
1da177e4 LT	349	return 0;
1da177e4	350	}