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 struct rb_node *__key_serial_next(struct rb_node *n) 95 { 96 while (n) { 97 struct key *key = rb_entry(n, struct key, serial_node); 98 if (key->user->user_ns == current_user_ns()) 99 break; 100 n = rb_next(n); 101 } 102 return n; 103 } 104 105 static struct rb_node *key_serial_next(struct rb_node *n) 106 { 107 return __key_serial_next(rb_next(n)); 108 } 109 110 static struct rb_node *key_serial_first(struct rb_root *r) 111 { 112 struct rb_node *n = rb_first(r); 113 return __key_serial_next(n); 114 } 115 116 static int proc_keys_open(struct inode *inode, struct file *file) 117 { 118 return seq_open(file, &proc_keys_ops); 119 120 } 121 122 static void *proc_keys_start(struct seq_file *p, loff_t *_pos) 123 { 124 struct rb_node *_p; 125 loff_t pos = *_pos; 126 127 spin_lock(&key_serial_lock); 128 129 _p = key_serial_first(&key_serial_tree); 130 while (pos > 0 && _p) { 131 pos--; 132 _p = key_serial_next(_p); 133 } 134 135 return _p; 136 137 } 138 139 static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos) 140 { 141 (*_pos)++; 142 return key_serial_next((struct rb_node *) v); 143 144 } 145 146 static void proc_keys_stop(struct seq_file *p, void *v) 147 { 148 spin_unlock(&key_serial_lock); 149 } 150 151 static 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 struct timespec now; 156 unsigned long timo; 157 char xbuf[12]; 158 int rc; 159 160 /* check whether the current task is allowed to view the key (assuming 161 * non-possession) 162 * - the caller holds a spinlock, and thus the RCU read lock, making our 163 * access to __current_cred() safe 164 */ 165 rc = key_task_permission(make_key_ref(key, 0), current_cred(), 166 KEY_VIEW); 167 if (rc < 0) 168 return 0; 169 170 now = current_kernel_time(); 171 172 rcu_read_lock(); 173 174 /* come up with a suitable timeout value */ 175 if (key->expiry == 0) { 176 memcpy(xbuf, "perm", 5); 177 } 178 else if (now.tv_sec >= key->expiry) { 179 memcpy(xbuf, "expd", 5); 180 } 181 else { 182 timo = key->expiry - now.tv_sec; 183 184 if (timo < 60) 185 sprintf(xbuf, "%lus", timo); 186 else if (timo < 60*60) 187 sprintf(xbuf, "%lum", timo / 60); 188 else if (timo < 60*60*24) 189 sprintf(xbuf, "%luh", timo / (60*60)); 190 else if (timo < 60*60*24*7) 191 sprintf(xbuf, "%lud", timo / (60*60*24)); 192 else 193 sprintf(xbuf, "%luw", timo / (60*60*24*7)); 194 } 195 196 #define showflag(KEY, LETTER, FLAG) \ 197 (test_bit(FLAG, &(KEY)->flags) ? LETTER : '-') 198 199 seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ", 200 key->serial, 201 showflag(key, 'I', KEY_FLAG_INSTANTIATED), 202 showflag(key, 'R', KEY_FLAG_REVOKED), 203 showflag(key, 'D', KEY_FLAG_DEAD), 204 showflag(key, 'Q', KEY_FLAG_IN_QUOTA), 205 showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT), 206 showflag(key, 'N', KEY_FLAG_NEGATIVE), 207 atomic_read(&key->usage), 208 xbuf, 209 key->perm, 210 key->uid, 211 key->gid, 212 key->type->name); 213 214 #undef showflag 215 216 if (key->type->describe) 217 key->type->describe(key, m); 218 seq_putc(m, '\n'); 219 220 rcu_read_unlock(); 221 222 return 0; 223 224 } 225 226 #endif /* CONFIG_KEYS_DEBUG_PROC_KEYS */ 227 228 static struct rb_node *__key_user_next(struct rb_node *n) 229 { 230 while (n) { 231 struct key_user *user = rb_entry(n, struct key_user, node); 232 if (user->user_ns == current_user_ns()) 233 break; 234 n = rb_next(n); 235 } 236 return n; 237 } 238 239 static struct rb_node *key_user_next(struct rb_node *n) 240 { 241 return __key_user_next(rb_next(n)); 242 } 243 244 static struct rb_node *key_user_first(struct rb_root *r) 245 { 246 struct rb_node *n = rb_first(r); 247 return __key_user_next(n); 248 } 249 /*****************************************************************************/ 250 /* 251 * implement "/proc/key-users" to provides a list of the key users 252 */ 253 static int proc_key_users_open(struct inode *inode, struct file *file) 254 { 255 return seq_open(file, &proc_key_users_ops); 256 257 } 258 259 static void *proc_key_users_start(struct seq_file *p, loff_t *_pos) 260 { 261 struct rb_node *_p; 262 loff_t pos = *_pos; 263 264 spin_lock(&key_user_lock); 265 266 _p = key_user_first(&key_user_tree); 267 while (pos > 0 && _p) { 268 pos--; 269 _p = key_user_next(_p); 270 } 271 272 return _p; 273 274 } 275 276 static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos) 277 { 278 (*_pos)++; 279 return key_user_next((struct rb_node *) v); 280 281 } 282 283 static void proc_key_users_stop(struct seq_file *p, void *v) 284 { 285 spin_unlock(&key_user_lock); 286 } 287 288 static int proc_key_users_show(struct seq_file *m, void *v) 289 { 290 struct rb_node *_p = v; 291 struct key_user *user = rb_entry(_p, struct key_user, node); 292 unsigned maxkeys = (user->uid == 0) ? 293 key_quota_root_maxkeys : key_quota_maxkeys; 294 unsigned maxbytes = (user->uid == 0) ? 295 key_quota_root_maxbytes : key_quota_maxbytes; 296 297 seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n", 298 user->uid, 299 atomic_read(&user->usage), 300 atomic_read(&user->nkeys), 301 atomic_read(&user->nikeys), 302 user->qnkeys, 303 maxkeys, 304 user->qnbytes, 305 maxbytes); 306 307 return 0; 308 309 } 310