| 1 | /** |
| 2 | * eCryptfs: Linux filesystem encryption layer |
| 3 | * |
| 4 | * Copyright (C) 2004-2008 International Business Machines Corp. |
| 5 | * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com> |
| 6 | * Tyler Hicks <tyhicks@ou.edu> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public License version |
| 10 | * 2 as published by the Free Software Foundation. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, but |
| 13 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA |
| 20 | * 02111-1307, USA. |
| 21 | */ |
| 22 | #include <linux/sched.h> |
| 23 | #include <linux/user_namespace.h> |
| 24 | #include <linux/nsproxy.h> |
| 25 | #include "ecryptfs_kernel.h" |
| 26 | |
| 27 | static LIST_HEAD(ecryptfs_msg_ctx_free_list); |
| 28 | static LIST_HEAD(ecryptfs_msg_ctx_alloc_list); |
| 29 | static struct mutex ecryptfs_msg_ctx_lists_mux; |
| 30 | |
| 31 | static struct hlist_head *ecryptfs_daemon_hash; |
| 32 | struct mutex ecryptfs_daemon_hash_mux; |
| 33 | static int ecryptfs_hash_buckets; |
| 34 | #define ecryptfs_uid_hash(uid) \ |
| 35 | hash_long((unsigned long)uid, ecryptfs_hash_buckets) |
| 36 | |
| 37 | static u32 ecryptfs_msg_counter; |
| 38 | static struct ecryptfs_msg_ctx *ecryptfs_msg_ctx_arr; |
| 39 | |
| 40 | /** |
| 41 | * ecryptfs_acquire_free_msg_ctx |
| 42 | * @msg_ctx: The context that was acquired from the free list |
| 43 | * |
| 44 | * Acquires a context element from the free list and locks the mutex |
| 45 | * on the context. Sets the msg_ctx task to current. Returns zero on |
| 46 | * success; non-zero on error or upon failure to acquire a free |
| 47 | * context element. Must be called with ecryptfs_msg_ctx_lists_mux |
| 48 | * held. |
| 49 | */ |
| 50 | static int ecryptfs_acquire_free_msg_ctx(struct ecryptfs_msg_ctx **msg_ctx) |
| 51 | { |
| 52 | struct list_head *p; |
| 53 | int rc; |
| 54 | |
| 55 | if (list_empty(&ecryptfs_msg_ctx_free_list)) { |
| 56 | printk(KERN_WARNING "%s: The eCryptfs free " |
| 57 | "context list is empty. It may be helpful to " |
| 58 | "specify the ecryptfs_message_buf_len " |
| 59 | "parameter to be greater than the current " |
| 60 | "value of [%d]\n", __func__, ecryptfs_message_buf_len); |
| 61 | rc = -ENOMEM; |
| 62 | goto out; |
| 63 | } |
| 64 | list_for_each(p, &ecryptfs_msg_ctx_free_list) { |
| 65 | *msg_ctx = list_entry(p, struct ecryptfs_msg_ctx, node); |
| 66 | if (mutex_trylock(&(*msg_ctx)->mux)) { |
| 67 | (*msg_ctx)->task = current; |
| 68 | rc = 0; |
| 69 | goto out; |
| 70 | } |
| 71 | } |
| 72 | rc = -ENOMEM; |
| 73 | out: |
| 74 | return rc; |
| 75 | } |
| 76 | |
| 77 | /** |
| 78 | * ecryptfs_msg_ctx_free_to_alloc |
| 79 | * @msg_ctx: The context to move from the free list to the alloc list |
| 80 | * |
| 81 | * Must be called with ecryptfs_msg_ctx_lists_mux held. |
| 82 | */ |
| 83 | static void ecryptfs_msg_ctx_free_to_alloc(struct ecryptfs_msg_ctx *msg_ctx) |
| 84 | { |
| 85 | list_move(&msg_ctx->node, &ecryptfs_msg_ctx_alloc_list); |
| 86 | msg_ctx->state = ECRYPTFS_MSG_CTX_STATE_PENDING; |
| 87 | msg_ctx->counter = ++ecryptfs_msg_counter; |
| 88 | } |
| 89 | |
| 90 | /** |
| 91 | * ecryptfs_msg_ctx_alloc_to_free |
| 92 | * @msg_ctx: The context to move from the alloc list to the free list |
| 93 | * |
| 94 | * Must be called with ecryptfs_msg_ctx_lists_mux held. |
| 95 | */ |
| 96 | void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx) |
| 97 | { |
| 98 | list_move(&(msg_ctx->node), &ecryptfs_msg_ctx_free_list); |
| 99 | if (msg_ctx->msg) |
| 100 | kfree(msg_ctx->msg); |
| 101 | msg_ctx->msg = NULL; |
| 102 | msg_ctx->state = ECRYPTFS_MSG_CTX_STATE_FREE; |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * ecryptfs_find_daemon_by_euid |
| 107 | * @euid: The effective user id which maps to the desired daemon id |
| 108 | * @user_ns: The namespace in which @euid applies |
| 109 | * @daemon: If return value is zero, points to the desired daemon pointer |
| 110 | * |
| 111 | * Must be called with ecryptfs_daemon_hash_mux held. |
| 112 | * |
| 113 | * Search the hash list for the given user id. |
| 114 | * |
| 115 | * Returns zero if the user id exists in the list; non-zero otherwise. |
| 116 | */ |
| 117 | int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon, uid_t euid, |
| 118 | struct user_namespace *user_ns) |
| 119 | { |
| 120 | struct hlist_node *elem; |
| 121 | int rc; |
| 122 | |
| 123 | hlist_for_each_entry(*daemon, elem, |
| 124 | &ecryptfs_daemon_hash[ecryptfs_uid_hash(euid)], |
| 125 | euid_chain) { |
| 126 | if ((*daemon)->euid == euid && (*daemon)->user_ns == user_ns) { |
| 127 | rc = 0; |
| 128 | goto out; |
| 129 | } |
| 130 | } |
| 131 | rc = -EINVAL; |
| 132 | out: |
| 133 | return rc; |
| 134 | } |
| 135 | |
| 136 | /** |
| 137 | * ecryptfs_spawn_daemon - Create and initialize a new daemon struct |
| 138 | * @daemon: Pointer to set to newly allocated daemon struct |
| 139 | * @euid: Effective user id for the daemon |
| 140 | * @user_ns: The namespace in which @euid applies |
| 141 | * @pid: Process id for the daemon |
| 142 | * |
| 143 | * Must be called ceremoniously while in possession of |
| 144 | * ecryptfs_sacred_daemon_hash_mux |
| 145 | * |
| 146 | * Returns zero on success; non-zero otherwise |
| 147 | */ |
| 148 | int |
| 149 | ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, uid_t euid, |
| 150 | struct user_namespace *user_ns, struct pid *pid) |
| 151 | { |
| 152 | int rc = 0; |
| 153 | |
| 154 | (*daemon) = kzalloc(sizeof(**daemon), GFP_KERNEL); |
| 155 | if (!(*daemon)) { |
| 156 | rc = -ENOMEM; |
| 157 | printk(KERN_ERR "%s: Failed to allocate [%zd] bytes of " |
| 158 | "GFP_KERNEL memory\n", __func__, sizeof(**daemon)); |
| 159 | goto out; |
| 160 | } |
| 161 | (*daemon)->euid = euid; |
| 162 | (*daemon)->user_ns = get_user_ns(user_ns); |
| 163 | (*daemon)->pid = get_pid(pid); |
| 164 | (*daemon)->task = current; |
| 165 | mutex_init(&(*daemon)->mux); |
| 166 | INIT_LIST_HEAD(&(*daemon)->msg_ctx_out_queue); |
| 167 | init_waitqueue_head(&(*daemon)->wait); |
| 168 | (*daemon)->num_queued_msg_ctx = 0; |
| 169 | hlist_add_head(&(*daemon)->euid_chain, |
| 170 | &ecryptfs_daemon_hash[ecryptfs_uid_hash(euid)]); |
| 171 | out: |
| 172 | return rc; |
| 173 | } |
| 174 | |
| 175 | /** |
| 176 | * ecryptfs_exorcise_daemon - Destroy the daemon struct |
| 177 | * |
| 178 | * Must be called ceremoniously while in possession of |
| 179 | * ecryptfs_daemon_hash_mux and the daemon's own mux. |
| 180 | */ |
| 181 | int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon) |
| 182 | { |
| 183 | struct ecryptfs_msg_ctx *msg_ctx, *msg_ctx_tmp; |
| 184 | int rc = 0; |
| 185 | |
| 186 | mutex_lock(&daemon->mux); |
| 187 | if ((daemon->flags & ECRYPTFS_DAEMON_IN_READ) |
| 188 | || (daemon->flags & ECRYPTFS_DAEMON_IN_POLL)) { |
| 189 | rc = -EBUSY; |
| 190 | printk(KERN_WARNING "%s: Attempt to destroy daemon with pid " |
| 191 | "[0x%p], but it is in the midst of a read or a poll\n", |
| 192 | __func__, daemon->pid); |
| 193 | mutex_unlock(&daemon->mux); |
| 194 | goto out; |
| 195 | } |
| 196 | list_for_each_entry_safe(msg_ctx, msg_ctx_tmp, |
| 197 | &daemon->msg_ctx_out_queue, daemon_out_list) { |
| 198 | list_del(&msg_ctx->daemon_out_list); |
| 199 | daemon->num_queued_msg_ctx--; |
| 200 | printk(KERN_WARNING "%s: Warning: dropping message that is in " |
| 201 | "the out queue of a dying daemon\n", __func__); |
| 202 | ecryptfs_msg_ctx_alloc_to_free(msg_ctx); |
| 203 | } |
| 204 | hlist_del(&daemon->euid_chain); |
| 205 | if (daemon->task) |
| 206 | wake_up_process(daemon->task); |
| 207 | if (daemon->pid) |
| 208 | put_pid(daemon->pid); |
| 209 | if (daemon->user_ns) |
| 210 | put_user_ns(daemon->user_ns); |
| 211 | mutex_unlock(&daemon->mux); |
| 212 | kzfree(daemon); |
| 213 | out: |
| 214 | return rc; |
| 215 | } |
| 216 | |
| 217 | /** |
| 218 | * ecryptfs_process_quit |
| 219 | * @euid: The user ID owner of the message |
| 220 | * @user_ns: The namespace in which @euid applies |
| 221 | * @pid: The process ID for the userspace program that sent the |
| 222 | * message |
| 223 | * |
| 224 | * Deletes the corresponding daemon for the given euid and pid, if |
| 225 | * it is the registered that is requesting the deletion. Returns zero |
| 226 | * after deleting the desired daemon; non-zero otherwise. |
| 227 | */ |
| 228 | int ecryptfs_process_quit(uid_t euid, struct user_namespace *user_ns, |
| 229 | struct pid *pid) |
| 230 | { |
| 231 | struct ecryptfs_daemon *daemon; |
| 232 | int rc; |
| 233 | |
| 234 | mutex_lock(&ecryptfs_daemon_hash_mux); |
| 235 | rc = ecryptfs_find_daemon_by_euid(&daemon, euid, user_ns); |
| 236 | if (rc || !daemon) { |
| 237 | rc = -EINVAL; |
| 238 | printk(KERN_ERR "Received request from user [%d] to " |
| 239 | "unregister unrecognized daemon [0x%p]\n", euid, pid); |
| 240 | goto out_unlock; |
| 241 | } |
| 242 | rc = ecryptfs_exorcise_daemon(daemon); |
| 243 | out_unlock: |
| 244 | mutex_unlock(&ecryptfs_daemon_hash_mux); |
| 245 | return rc; |
| 246 | } |
| 247 | |
| 248 | /** |
| 249 | * ecryptfs_process_reponse |
| 250 | * @msg: The ecryptfs message received; the caller should sanity check |
| 251 | * msg->data_len and free the memory |
| 252 | * @pid: The process ID of the userspace application that sent the |
| 253 | * message |
| 254 | * @seq: The sequence number of the message; must match the sequence |
| 255 | * number for the existing message context waiting for this |
| 256 | * response |
| 257 | * |
| 258 | * Processes a response message after sending an operation request to |
| 259 | * userspace. Some other process is awaiting this response. Before |
| 260 | * sending out its first communications, the other process allocated a |
| 261 | * msg_ctx from the ecryptfs_msg_ctx_arr at a particular index. The |
| 262 | * response message contains this index so that we can copy over the |
| 263 | * response message into the msg_ctx that the process holds a |
| 264 | * reference to. The other process is going to wake up, check to see |
| 265 | * that msg_ctx->state == ECRYPTFS_MSG_CTX_STATE_DONE, and then |
| 266 | * proceed to read off and process the response message. Returns zero |
| 267 | * upon delivery to desired context element; non-zero upon delivery |
| 268 | * failure or error. |
| 269 | * |
| 270 | * Returns zero on success; non-zero otherwise |
| 271 | */ |
| 272 | int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid, |
| 273 | struct user_namespace *user_ns, struct pid *pid, |
| 274 | u32 seq) |
| 275 | { |
| 276 | struct ecryptfs_daemon *daemon; |
| 277 | struct ecryptfs_msg_ctx *msg_ctx; |
| 278 | size_t msg_size; |
| 279 | struct nsproxy *nsproxy; |
| 280 | struct user_namespace *tsk_user_ns; |
| 281 | uid_t ctx_euid; |
| 282 | int rc; |
| 283 | |
| 284 | if (msg->index >= ecryptfs_message_buf_len) { |
| 285 | rc = -EINVAL; |
| 286 | printk(KERN_ERR "%s: Attempt to reference " |
| 287 | "context buffer at index [%d]; maximum " |
| 288 | "allowable is [%d]\n", __func__, msg->index, |
| 289 | (ecryptfs_message_buf_len - 1)); |
| 290 | goto out; |
| 291 | } |
| 292 | msg_ctx = &ecryptfs_msg_ctx_arr[msg->index]; |
| 293 | mutex_lock(&msg_ctx->mux); |
| 294 | mutex_lock(&ecryptfs_daemon_hash_mux); |
| 295 | rcu_read_lock(); |
| 296 | nsproxy = task_nsproxy(msg_ctx->task); |
| 297 | if (nsproxy == NULL) { |
| 298 | rc = -EBADMSG; |
| 299 | printk(KERN_ERR "%s: Receiving process is a zombie. Dropping " |
| 300 | "message.\n", __func__); |
| 301 | rcu_read_unlock(); |
| 302 | mutex_unlock(&ecryptfs_daemon_hash_mux); |
| 303 | goto wake_up; |
| 304 | } |
| 305 | tsk_user_ns = __task_cred(msg_ctx->task)->user->user_ns; |
| 306 | ctx_euid = task_euid(msg_ctx->task); |
| 307 | rc = ecryptfs_find_daemon_by_euid(&daemon, ctx_euid, tsk_user_ns); |
| 308 | rcu_read_unlock(); |
| 309 | mutex_unlock(&ecryptfs_daemon_hash_mux); |
| 310 | if (rc) { |
| 311 | rc = -EBADMSG; |
| 312 | printk(KERN_WARNING "%s: User [%d] received a " |
| 313 | "message response from process [0x%p] but does " |
| 314 | "not have a registered daemon\n", __func__, |
| 315 | ctx_euid, pid); |
| 316 | goto wake_up; |
| 317 | } |
| 318 | if (ctx_euid != euid) { |
| 319 | rc = -EBADMSG; |
| 320 | printk(KERN_WARNING "%s: Received message from user " |
| 321 | "[%d]; expected message from user [%d]\n", __func__, |
| 322 | euid, ctx_euid); |
| 323 | goto unlock; |
| 324 | } |
| 325 | if (tsk_user_ns != user_ns) { |
| 326 | rc = -EBADMSG; |
| 327 | printk(KERN_WARNING "%s: Received message from user_ns " |
| 328 | "[0x%p]; expected message from user_ns [0x%p]\n", |
| 329 | __func__, user_ns, tsk_user_ns); |
| 330 | goto unlock; |
| 331 | } |
| 332 | if (daemon->pid != pid) { |
| 333 | rc = -EBADMSG; |
| 334 | printk(KERN_ERR "%s: User [%d] sent a message response " |
| 335 | "from an unrecognized process [0x%p]\n", |
| 336 | __func__, ctx_euid, pid); |
| 337 | goto unlock; |
| 338 | } |
| 339 | if (msg_ctx->state != ECRYPTFS_MSG_CTX_STATE_PENDING) { |
| 340 | rc = -EINVAL; |
| 341 | printk(KERN_WARNING "%s: Desired context element is not " |
| 342 | "pending a response\n", __func__); |
| 343 | goto unlock; |
| 344 | } else if (msg_ctx->counter != seq) { |
| 345 | rc = -EINVAL; |
| 346 | printk(KERN_WARNING "%s: Invalid message sequence; " |
| 347 | "expected [%d]; received [%d]\n", __func__, |
| 348 | msg_ctx->counter, seq); |
| 349 | goto unlock; |
| 350 | } |
| 351 | msg_size = (sizeof(*msg) + msg->data_len); |
| 352 | msg_ctx->msg = kmalloc(msg_size, GFP_KERNEL); |
| 353 | if (!msg_ctx->msg) { |
| 354 | rc = -ENOMEM; |
| 355 | printk(KERN_ERR "%s: Failed to allocate [%zd] bytes of " |
| 356 | "GFP_KERNEL memory\n", __func__, msg_size); |
| 357 | goto unlock; |
| 358 | } |
| 359 | memcpy(msg_ctx->msg, msg, msg_size); |
| 360 | msg_ctx->state = ECRYPTFS_MSG_CTX_STATE_DONE; |
| 361 | rc = 0; |
| 362 | wake_up: |
| 363 | wake_up_process(msg_ctx->task); |
| 364 | unlock: |
| 365 | mutex_unlock(&msg_ctx->mux); |
| 366 | out: |
| 367 | return rc; |
| 368 | } |
| 369 | |
| 370 | /** |
| 371 | * ecryptfs_send_message_locked |
| 372 | * @data: The data to send |
| 373 | * @data_len: The length of data |
| 374 | * @msg_ctx: The message context allocated for the send |
| 375 | * |
| 376 | * Must be called with ecryptfs_daemon_hash_mux held. |
| 377 | * |
| 378 | * Returns zero on success; non-zero otherwise |
| 379 | */ |
| 380 | static int |
| 381 | ecryptfs_send_message_locked(char *data, int data_len, u8 msg_type, |
| 382 | struct ecryptfs_msg_ctx **msg_ctx) |
| 383 | { |
| 384 | struct ecryptfs_daemon *daemon; |
| 385 | uid_t euid = current_euid(); |
| 386 | int rc; |
| 387 | |
| 388 | rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns()); |
| 389 | if (rc || !daemon) { |
| 390 | rc = -ENOTCONN; |
| 391 | printk(KERN_ERR "%s: User [%d] does not have a daemon " |
| 392 | "registered\n", __func__, euid); |
| 393 | goto out; |
| 394 | } |
| 395 | mutex_lock(&ecryptfs_msg_ctx_lists_mux); |
| 396 | rc = ecryptfs_acquire_free_msg_ctx(msg_ctx); |
| 397 | if (rc) { |
| 398 | mutex_unlock(&ecryptfs_msg_ctx_lists_mux); |
| 399 | printk(KERN_WARNING "%s: Could not claim a free " |
| 400 | "context element\n", __func__); |
| 401 | goto out; |
| 402 | } |
| 403 | ecryptfs_msg_ctx_free_to_alloc(*msg_ctx); |
| 404 | mutex_unlock(&(*msg_ctx)->mux); |
| 405 | mutex_unlock(&ecryptfs_msg_ctx_lists_mux); |
| 406 | rc = ecryptfs_send_miscdev(data, data_len, *msg_ctx, msg_type, 0, |
| 407 | daemon); |
| 408 | if (rc) |
| 409 | printk(KERN_ERR "%s: Error attempting to send message to " |
| 410 | "userspace daemon; rc = [%d]\n", __func__, rc); |
| 411 | out: |
| 412 | return rc; |
| 413 | } |
| 414 | |
| 415 | /** |
| 416 | * ecryptfs_send_message |
| 417 | * @data: The data to send |
| 418 | * @data_len: The length of data |
| 419 | * @msg_ctx: The message context allocated for the send |
| 420 | * |
| 421 | * Grabs ecryptfs_daemon_hash_mux. |
| 422 | * |
| 423 | * Returns zero on success; non-zero otherwise |
| 424 | */ |
| 425 | int ecryptfs_send_message(char *data, int data_len, |
| 426 | struct ecryptfs_msg_ctx **msg_ctx) |
| 427 | { |
| 428 | int rc; |
| 429 | |
| 430 | mutex_lock(&ecryptfs_daemon_hash_mux); |
| 431 | rc = ecryptfs_send_message_locked(data, data_len, ECRYPTFS_MSG_REQUEST, |
| 432 | msg_ctx); |
| 433 | mutex_unlock(&ecryptfs_daemon_hash_mux); |
| 434 | return rc; |
| 435 | } |
| 436 | |
| 437 | /** |
| 438 | * ecryptfs_wait_for_response |
| 439 | * @msg_ctx: The context that was assigned when sending a message |
| 440 | * @msg: The incoming message from userspace; not set if rc != 0 |
| 441 | * |
| 442 | * Sleeps until awaken by ecryptfs_receive_message or until the amount |
| 443 | * of time exceeds ecryptfs_message_wait_timeout. If zero is |
| 444 | * returned, msg will point to a valid message from userspace; a |
| 445 | * non-zero value is returned upon failure to receive a message or an |
| 446 | * error occurs. Callee must free @msg on success. |
| 447 | */ |
| 448 | int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx, |
| 449 | struct ecryptfs_message **msg) |
| 450 | { |
| 451 | signed long timeout = ecryptfs_message_wait_timeout * HZ; |
| 452 | int rc = 0; |
| 453 | |
| 454 | sleep: |
| 455 | timeout = schedule_timeout_interruptible(timeout); |
| 456 | mutex_lock(&ecryptfs_msg_ctx_lists_mux); |
| 457 | mutex_lock(&msg_ctx->mux); |
| 458 | if (msg_ctx->state != ECRYPTFS_MSG_CTX_STATE_DONE) { |
| 459 | if (timeout) { |
| 460 | mutex_unlock(&msg_ctx->mux); |
| 461 | mutex_unlock(&ecryptfs_msg_ctx_lists_mux); |
| 462 | goto sleep; |
| 463 | } |
| 464 | rc = -ENOMSG; |
| 465 | } else { |
| 466 | *msg = msg_ctx->msg; |
| 467 | msg_ctx->msg = NULL; |
| 468 | } |
| 469 | ecryptfs_msg_ctx_alloc_to_free(msg_ctx); |
| 470 | mutex_unlock(&msg_ctx->mux); |
| 471 | mutex_unlock(&ecryptfs_msg_ctx_lists_mux); |
| 472 | return rc; |
| 473 | } |
| 474 | |
| 475 | int ecryptfs_init_messaging(void) |
| 476 | { |
| 477 | int i; |
| 478 | int rc = 0; |
| 479 | |
| 480 | if (ecryptfs_number_of_users > ECRYPTFS_MAX_NUM_USERS) { |
| 481 | ecryptfs_number_of_users = ECRYPTFS_MAX_NUM_USERS; |
| 482 | printk(KERN_WARNING "%s: Specified number of users is " |
| 483 | "too large, defaulting to [%d] users\n", __func__, |
| 484 | ecryptfs_number_of_users); |
| 485 | } |
| 486 | mutex_init(&ecryptfs_daemon_hash_mux); |
| 487 | mutex_lock(&ecryptfs_daemon_hash_mux); |
| 488 | ecryptfs_hash_buckets = 1; |
| 489 | while (ecryptfs_number_of_users >> ecryptfs_hash_buckets) |
| 490 | ecryptfs_hash_buckets++; |
| 491 | ecryptfs_daemon_hash = kmalloc((sizeof(struct hlist_head) |
| 492 | * ecryptfs_hash_buckets), GFP_KERNEL); |
| 493 | if (!ecryptfs_daemon_hash) { |
| 494 | rc = -ENOMEM; |
| 495 | printk(KERN_ERR "%s: Failed to allocate memory\n", __func__); |
| 496 | mutex_unlock(&ecryptfs_daemon_hash_mux); |
| 497 | goto out; |
| 498 | } |
| 499 | for (i = 0; i < ecryptfs_hash_buckets; i++) |
| 500 | INIT_HLIST_HEAD(&ecryptfs_daemon_hash[i]); |
| 501 | mutex_unlock(&ecryptfs_daemon_hash_mux); |
| 502 | ecryptfs_msg_ctx_arr = kmalloc((sizeof(struct ecryptfs_msg_ctx) |
| 503 | * ecryptfs_message_buf_len), |
| 504 | GFP_KERNEL); |
| 505 | if (!ecryptfs_msg_ctx_arr) { |
| 506 | rc = -ENOMEM; |
| 507 | printk(KERN_ERR "%s: Failed to allocate memory\n", __func__); |
| 508 | goto out; |
| 509 | } |
| 510 | mutex_init(&ecryptfs_msg_ctx_lists_mux); |
| 511 | mutex_lock(&ecryptfs_msg_ctx_lists_mux); |
| 512 | ecryptfs_msg_counter = 0; |
| 513 | for (i = 0; i < ecryptfs_message_buf_len; i++) { |
| 514 | INIT_LIST_HEAD(&ecryptfs_msg_ctx_arr[i].node); |
| 515 | INIT_LIST_HEAD(&ecryptfs_msg_ctx_arr[i].daemon_out_list); |
| 516 | mutex_init(&ecryptfs_msg_ctx_arr[i].mux); |
| 517 | mutex_lock(&ecryptfs_msg_ctx_arr[i].mux); |
| 518 | ecryptfs_msg_ctx_arr[i].index = i; |
| 519 | ecryptfs_msg_ctx_arr[i].state = ECRYPTFS_MSG_CTX_STATE_FREE; |
| 520 | ecryptfs_msg_ctx_arr[i].counter = 0; |
| 521 | ecryptfs_msg_ctx_arr[i].task = NULL; |
| 522 | ecryptfs_msg_ctx_arr[i].msg = NULL; |
| 523 | list_add_tail(&ecryptfs_msg_ctx_arr[i].node, |
| 524 | &ecryptfs_msg_ctx_free_list); |
| 525 | mutex_unlock(&ecryptfs_msg_ctx_arr[i].mux); |
| 526 | } |
| 527 | mutex_unlock(&ecryptfs_msg_ctx_lists_mux); |
| 528 | rc = ecryptfs_init_ecryptfs_miscdev(); |
| 529 | if (rc) |
| 530 | ecryptfs_release_messaging(); |
| 531 | out: |
| 532 | return rc; |
| 533 | } |
| 534 | |
| 535 | void ecryptfs_release_messaging(void) |
| 536 | { |
| 537 | if (ecryptfs_msg_ctx_arr) { |
| 538 | int i; |
| 539 | |
| 540 | mutex_lock(&ecryptfs_msg_ctx_lists_mux); |
| 541 | for (i = 0; i < ecryptfs_message_buf_len; i++) { |
| 542 | mutex_lock(&ecryptfs_msg_ctx_arr[i].mux); |
| 543 | if (ecryptfs_msg_ctx_arr[i].msg) |
| 544 | kfree(ecryptfs_msg_ctx_arr[i].msg); |
| 545 | mutex_unlock(&ecryptfs_msg_ctx_arr[i].mux); |
| 546 | } |
| 547 | kfree(ecryptfs_msg_ctx_arr); |
| 548 | mutex_unlock(&ecryptfs_msg_ctx_lists_mux); |
| 549 | } |
| 550 | if (ecryptfs_daemon_hash) { |
| 551 | struct hlist_node *elem; |
| 552 | struct ecryptfs_daemon *daemon; |
| 553 | int i; |
| 554 | |
| 555 | mutex_lock(&ecryptfs_daemon_hash_mux); |
| 556 | for (i = 0; i < ecryptfs_hash_buckets; i++) { |
| 557 | int rc; |
| 558 | |
| 559 | hlist_for_each_entry(daemon, elem, |
| 560 | &ecryptfs_daemon_hash[i], |
| 561 | euid_chain) { |
| 562 | rc = ecryptfs_exorcise_daemon(daemon); |
| 563 | if (rc) |
| 564 | printk(KERN_ERR "%s: Error whilst " |
| 565 | "attempting to destroy daemon; " |
| 566 | "rc = [%d]. Dazed and confused, " |
| 567 | "but trying to continue.\n", |
| 568 | __func__, rc); |
| 569 | } |
| 570 | } |
| 571 | kfree(ecryptfs_daemon_hash); |
| 572 | mutex_unlock(&ecryptfs_daemon_hash_mux); |
| 573 | } |
| 574 | ecryptfs_destroy_ecryptfs_miscdev(); |
| 575 | return; |
| 576 | } |