xref: /openbmc/linux/security/keys/proc.c (revision 384740dc)
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>
15 #include <linux/slab.h>
16 #include <linux/fs.h>
17 #include <linux/proc_fs.h>
18 #include <linux/seq_file.h>
19 #include <asm/errno.h>
20 #include "internal.h"
21 
22 #ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
23 static int proc_keys_open(struct inode *inode, struct file *file);
24 static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
25 static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
26 static void proc_keys_stop(struct seq_file *p, void *v);
27 static int proc_keys_show(struct seq_file *m, void *v);
28 
29 static const struct seq_operations proc_keys_ops = {
30 	.start	= proc_keys_start,
31 	.next	= proc_keys_next,
32 	.stop	= proc_keys_stop,
33 	.show	= proc_keys_show,
34 };
35 
36 static const struct file_operations proc_keys_fops = {
37 	.open		= proc_keys_open,
38 	.read		= seq_read,
39 	.llseek		= seq_lseek,
40 	.release	= seq_release,
41 };
42 #endif
43 
44 static int proc_key_users_open(struct inode *inode, struct file *file);
45 static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
46 static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
47 static void proc_key_users_stop(struct seq_file *p, void *v);
48 static int proc_key_users_show(struct seq_file *m, void *v);
49 
50 static const struct seq_operations proc_key_users_ops = {
51 	.start	= proc_key_users_start,
52 	.next	= proc_key_users_next,
53 	.stop	= proc_key_users_stop,
54 	.show	= proc_key_users_show,
55 };
56 
57 static const struct file_operations proc_key_users_fops = {
58 	.open		= proc_key_users_open,
59 	.read		= seq_read,
60 	.llseek		= seq_lseek,
61 	.release	= seq_release,
62 };
63 
64 /*****************************************************************************/
65 /*
66  * declare the /proc files
67  */
68 static int __init key_proc_init(void)
69 {
70 	struct proc_dir_entry *p;
71 
72 #ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
73 	p = proc_create("keys", 0, NULL, &proc_keys_fops);
74 	if (!p)
75 		panic("Cannot create /proc/keys\n");
76 #endif
77 
78 	p = proc_create("key-users", 0, NULL, &proc_key_users_fops);
79 	if (!p)
80 		panic("Cannot create /proc/key-users\n");
81 
82 	return 0;
83 
84 } /* end key_proc_init() */
85 
86 __initcall(key_proc_init);
87 
88 /*****************************************************************************/
89 /*
90  * implement "/proc/keys" to provides a list of the keys on the system
91  */
92 #ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
93 
94 static int proc_keys_open(struct inode *inode, struct file *file)
95 {
96 	return seq_open(file, &proc_keys_ops);
97 
98 }
99 
100 static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
101 {
102 	struct rb_node *_p;
103 	loff_t pos = *_pos;
104 
105 	spin_lock(&key_serial_lock);
106 
107 	_p = rb_first(&key_serial_tree);
108 	while (pos > 0 && _p) {
109 		pos--;
110 		_p = rb_next(_p);
111 	}
112 
113 	return _p;
114 
115 }
116 
117 static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
118 {
119 	(*_pos)++;
120 	return rb_next((struct rb_node *) v);
121 
122 }
123 
124 static void proc_keys_stop(struct seq_file *p, void *v)
125 {
126 	spin_unlock(&key_serial_lock);
127 }
128 
129 static int proc_keys_show(struct seq_file *m, void *v)
130 {
131 	struct rb_node *_p = v;
132 	struct key *key = rb_entry(_p, struct key, serial_node);
133 	struct timespec now;
134 	unsigned long timo;
135 	char xbuf[12];
136 	int rc;
137 
138 	/* check whether the current task is allowed to view the key (assuming
139 	 * non-possession) */
140 	rc = key_task_permission(make_key_ref(key, 0), current, KEY_VIEW);
141 	if (rc < 0)
142 		return 0;
143 
144 	now = current_kernel_time();
145 
146 	rcu_read_lock();
147 
148 	/* come up with a suitable timeout value */
149 	if (key->expiry == 0) {
150 		memcpy(xbuf, "perm", 5);
151 	}
152 	else if (now.tv_sec >= key->expiry) {
153 		memcpy(xbuf, "expd", 5);
154 	}
155 	else {
156 		timo = key->expiry - now.tv_sec;
157 
158 		if (timo < 60)
159 			sprintf(xbuf, "%lus", timo);
160 		else if (timo < 60*60)
161 			sprintf(xbuf, "%lum", timo / 60);
162 		else if (timo < 60*60*24)
163 			sprintf(xbuf, "%luh", timo / (60*60));
164 		else if (timo < 60*60*24*7)
165 			sprintf(xbuf, "%lud", timo / (60*60*24));
166 		else
167 			sprintf(xbuf, "%luw", timo / (60*60*24*7));
168 	}
169 
170 #define showflag(KEY, LETTER, FLAG) \
171 	(test_bit(FLAG,	&(KEY)->flags) ? LETTER : '-')
172 
173 	seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
174 		   key->serial,
175 		   showflag(key, 'I', KEY_FLAG_INSTANTIATED),
176 		   showflag(key, 'R', KEY_FLAG_REVOKED),
177 		   showflag(key, 'D', KEY_FLAG_DEAD),
178 		   showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
179 		   showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
180 		   showflag(key, 'N', KEY_FLAG_NEGATIVE),
181 		   atomic_read(&key->usage),
182 		   xbuf,
183 		   key->perm,
184 		   key->uid,
185 		   key->gid,
186 		   key->type->name);
187 
188 #undef showflag
189 
190 	if (key->type->describe)
191 		key->type->describe(key, m);
192 	seq_putc(m, '\n');
193 
194 	rcu_read_unlock();
195 
196 	return 0;
197 
198 }
199 
200 #endif /* CONFIG_KEYS_DEBUG_PROC_KEYS */
201 
202 /*****************************************************************************/
203 /*
204  * implement "/proc/key-users" to provides a list of the key users
205  */
206 static int proc_key_users_open(struct inode *inode, struct file *file)
207 {
208 	return seq_open(file, &proc_key_users_ops);
209 
210 }
211 
212 static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
213 {
214 	struct rb_node *_p;
215 	loff_t pos = *_pos;
216 
217 	spin_lock(&key_user_lock);
218 
219 	_p = rb_first(&key_user_tree);
220 	while (pos > 0 && _p) {
221 		pos--;
222 		_p = rb_next(_p);
223 	}
224 
225 	return _p;
226 
227 }
228 
229 static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
230 {
231 	(*_pos)++;
232 	return rb_next((struct rb_node *) v);
233 
234 }
235 
236 static void proc_key_users_stop(struct seq_file *p, void *v)
237 {
238 	spin_unlock(&key_user_lock);
239 }
240 
241 static int proc_key_users_show(struct seq_file *m, void *v)
242 {
243 	struct rb_node *_p = v;
244 	struct key_user *user = rb_entry(_p, struct key_user, node);
245 	unsigned maxkeys = (user->uid == 0) ?
246 		key_quota_root_maxkeys : key_quota_maxkeys;
247 	unsigned maxbytes = (user->uid == 0) ?
248 		key_quota_root_maxbytes : key_quota_maxbytes;
249 
250 	seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
251 		   user->uid,
252 		   atomic_read(&user->usage),
253 		   atomic_read(&user->nkeys),
254 		   atomic_read(&user->nikeys),
255 		   user->qnkeys,
256 		   maxkeys,
257 		   user->qnbytes,
258 		   maxbytes);
259 
260 	return 0;
261 
262 }
263