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 */
key_proc_init(void)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
proc_keys_open(struct inode * inode,struct file * file)94 static int proc_keys_open(struct inode *inode, struct file *file)
95 {
96 return seq_open(file, &proc_keys_ops);
97
98 }
99
proc_keys_start(struct seq_file * p,loff_t * _pos)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
proc_keys_next(struct seq_file * p,void * v,loff_t * _pos)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
proc_keys_stop(struct seq_file * p,void * v)124 static void proc_keys_stop(struct seq_file *p, void *v)
125 {
126 spin_unlock(&key_serial_lock);
127 }
128
proc_keys_show(struct seq_file * m,void * v)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 * - the caller holds a spinlock, and thus the RCU read lock, making our
141 * access to __current_cred() safe
142 */
143 rc = key_task_permission(make_key_ref(key, 0), current_cred(),
144 KEY_VIEW);
145 if (rc < 0)
146 return 0;
147
148 now = current_kernel_time();
149
150 rcu_read_lock();
151
152 /* come up with a suitable timeout value */
153 if (key->expiry == 0) {
154 memcpy(xbuf, "perm", 5);
155 }
156 else if (now.tv_sec >= key->expiry) {
157 memcpy(xbuf, "expd", 5);
158 }
159 else {
160 timo = key->expiry - now.tv_sec;
161
162 if (timo < 60)
163 sprintf(xbuf, "%lus", timo);
164 else if (timo < 60*60)
165 sprintf(xbuf, "%lum", timo / 60);
166 else if (timo < 60*60*24)
167 sprintf(xbuf, "%luh", timo / (60*60));
168 else if (timo < 60*60*24*7)
169 sprintf(xbuf, "%lud", timo / (60*60*24));
170 else
171 sprintf(xbuf, "%luw", timo / (60*60*24*7));
172 }
173
174 #define showflag(KEY, LETTER, FLAG) \
175 (test_bit(FLAG, &(KEY)->flags) ? LETTER : '-')
176
177 seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
178 key->serial,
179 showflag(key, 'I', KEY_FLAG_INSTANTIATED),
180 showflag(key, 'R', KEY_FLAG_REVOKED),
181 showflag(key, 'D', KEY_FLAG_DEAD),
182 showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
183 showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
184 showflag(key, 'N', KEY_FLAG_NEGATIVE),
185 atomic_read(&key->usage),
186 xbuf,
187 key->perm,
188 key->uid,
189 key->gid,
190 key->type->name);
191
192 #undef showflag
193
194 if (key->type->describe)
195 key->type->describe(key, m);
196 seq_putc(m, '\n');
197
198 rcu_read_unlock();
199
200 return 0;
201
202 }
203
204 #endif /* CONFIG_KEYS_DEBUG_PROC_KEYS */
205
206 /*****************************************************************************/
207 /*
208 * implement "/proc/key-users" to provides a list of the key users
209 */
proc_key_users_open(struct inode * inode,struct file * file)210 static int proc_key_users_open(struct inode *inode, struct file *file)
211 {
212 return seq_open(file, &proc_key_users_ops);
213
214 }
215
proc_key_users_start(struct seq_file * p,loff_t * _pos)216 static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
217 {
218 struct rb_node *_p;
219 loff_t pos = *_pos;
220
221 spin_lock(&key_user_lock);
222
223 _p = rb_first(&key_user_tree);
224 while (pos > 0 && _p) {
225 pos--;
226 _p = rb_next(_p);
227 }
228
229 return _p;
230
231 }
232
proc_key_users_next(struct seq_file * p,void * v,loff_t * _pos)233 static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
234 {
235 (*_pos)++;
236 return rb_next((struct rb_node *) v);
237
238 }
239
proc_key_users_stop(struct seq_file * p,void * v)240 static void proc_key_users_stop(struct seq_file *p, void *v)
241 {
242 spin_unlock(&key_user_lock);
243 }
244
proc_key_users_show(struct seq_file * m,void * v)245 static int proc_key_users_show(struct seq_file *m, void *v)
246 {
247 struct rb_node *_p = v;
248 struct key_user *user = rb_entry(_p, struct key_user, node);
249 unsigned maxkeys = (user->uid == 0) ?
250 key_quota_root_maxkeys : key_quota_maxkeys;
251 unsigned maxbytes = (user->uid == 0) ?
252 key_quota_root_maxbytes : key_quota_maxbytes;
253
254 seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
255 user->uid,
256 atomic_read(&user->usage),
257 atomic_read(&user->nkeys),
258 atomic_read(&user->nikeys),
259 user->qnkeys,
260 maxkeys,
261 user->qnbytes,
262 maxbytes);
263
264 return 0;
265
266 }
267