fs/ksmbd/server.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
   4  *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
   5  */
   6
   7 #include "glob.h"
   8 #include "oplock.h"
   9 #include "misc.h"
  10 #include <linux/sched/signal.h>
  11 #include <linux/workqueue.h>
  12 #include <linux/sysfs.h>
  13 #include <linux/module.h>
  14 #include <linux/moduleparam.h>
  15
  16 #include "server.h"
  17 #include "smb_common.h"
  18 #include "smbstatus.h"
  19 #include "connection.h"
  20 #include "transport_ipc.h"
  21 #include "mgmt/user_session.h"
  22 #include "crypto_ctx.h"
  23 #include "auth.h"
  24
  25 int ksmbd_debug_types;
  26
  27 struct ksmbd_server_config server_conf;
  28
  29 enum SERVER_CTRL_TYPE {
  30         SERVER_CTRL_TYPE_INIT,
  31         SERVER_CTRL_TYPE_RESET,
  32 };
  33
  34 struct server_ctrl_struct {
  35         int                     type;
  36         struct work_struct      ctrl_work;
  37 };
  38
  39 static DEFINE_MUTEX(ctrl_lock);
  40
  41 static int ___server_conf_set(int idx, char *val)
  42 {
  43         if (idx >= ARRAY_SIZE(server_conf.conf))
  44                 return -EINVAL;
  45
  46         if (!val || val[0] == 0x00)
  47                 return -EINVAL;
  48
  49         kfree(server_conf.conf[idx]);
  50         server_conf.conf[idx] = kstrdup(val, GFP_KERNEL);
  51         if (!server_conf.conf[idx])
  52                 return -ENOMEM;
  53         return 0;
  54 }
  55
  56 int ksmbd_set_netbios_name(char *v)
  57 {
  58         return ___server_conf_set(SERVER_CONF_NETBIOS_NAME, v);
  59 }
  60
  61 int ksmbd_set_server_string(char *v)
  62 {
  63         return ___server_conf_set(SERVER_CONF_SERVER_STRING, v);
  64 }
  65
  66 int ksmbd_set_work_group(char *v)
  67 {
  68         return ___server_conf_set(SERVER_CONF_WORK_GROUP, v);
  69 }
  70
  71 char *ksmbd_netbios_name(void)
  72 {
  73         return server_conf.conf[SERVER_CONF_NETBIOS_NAME];
  74 }
  75
  76 char *ksmbd_server_string(void)
  77 {
  78         return server_conf.conf[SERVER_CONF_SERVER_STRING];
  79 }
  80
  81 char *ksmbd_work_group(void)
  82 {
  83         return server_conf.conf[SERVER_CONF_WORK_GROUP];
  84 }
  85
  86 /**
  87  * check_conn_state() - check state of server thread connection
  88  * @work:     smb work containing server thread information
  89  *
  90  * Return:      0 on valid connection, otherwise 1 to reconnect
  91  */
  92 static inline int check_conn_state(struct ksmbd_work *work)
  93 {
  94         struct smb_hdr *rsp_hdr;
  95
  96         if (ksmbd_conn_exiting(work) || ksmbd_conn_need_reconnect(work)) {
  97                 rsp_hdr = work->response_buf;
  98                 rsp_hdr->Status.CifsError = STATUS_CONNECTION_DISCONNECTED;
  99                 return 1;
 100         }
 101         return 0;
 102 }
 103
 104 #define SERVER_HANDLER_CONTINUE         0
 105 #define SERVER_HANDLER_ABORT            1
 106
 107 static int __process_request(struct ksmbd_work *work, struct ksmbd_conn *conn,
 108                              u16 *cmd)
 109 {
 110         struct smb_version_cmds *cmds;
 111         u16 command;
 112         int ret;
 113
 114         if (check_conn_state(work))
 115                 return SERVER_HANDLER_CONTINUE;
 116
 117         if (ksmbd_verify_smb_message(work))
 118                 return SERVER_HANDLER_ABORT;
 119
 120         command = conn->ops->get_cmd_val(work);
 121         *cmd = command;
 122
 123 andx_again:
 124         if (command >= conn->max_cmds) {
 125                 conn->ops->set_rsp_status(work, STATUS_INVALID_PARAMETER);
 126                 return SERVER_HANDLER_CONTINUE;
 127         }
 128
 129         cmds = &conn->cmds[command];
 130         if (!cmds->proc) {
 131                 ksmbd_debug(SMB, "*** not implemented yet cmd = %x\n", command);
 132                 conn->ops->set_rsp_status(work, STATUS_NOT_IMPLEMENTED);
 133                 return SERVER_HANDLER_CONTINUE;
 134         }
 135
 136         if (work->sess && conn->ops->is_sign_req(work, command)) {
 137                 ret = conn->ops->check_sign_req(work);
 138                 if (!ret) {
 139                         conn->ops->set_rsp_status(work, STATUS_ACCESS_DENIED);
 140                         return SERVER_HANDLER_CONTINUE;
 141                 }
 142         }
 143
 144         ret = cmds->proc(work);
 145
 146         if (ret < 0)
 147                 ksmbd_debug(CONN, "Failed to process %u [%d]\n", command, ret);
 148         /* AndX commands - chained request can return positive values */
 149         else if (ret > 0) {
 150                 command = ret;
 151                 *cmd = command;
 152                 goto andx_again;
 153         }
 154
 155         if (work->send_no_response)
 156                 return SERVER_HANDLER_ABORT;
 157         return SERVER_HANDLER_CONTINUE;
 158 }
 159
 160 static void __handle_ksmbd_work(struct ksmbd_work *work,
 161                                 struct ksmbd_conn *conn)
 162 {
 163         u16 command = 0;
 164         int rc;
 165
 166         if (conn->ops->allocate_rsp_buf(work))
 167                 return;
 168
 169         if (conn->ops->is_transform_hdr &&
 170             conn->ops->is_transform_hdr(work->request_buf)) {
 171                 rc = conn->ops->decrypt_req(work);
 172                 if (rc < 0) {
 173                         conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
 174                         goto send;
 175                 }
 176
 177                 work->encrypted = true;
 178         }
 179
 180         rc = conn->ops->init_rsp_hdr(work);
 181         if (rc) {
 182                 /* either uid or tid is not correct */
 183                 conn->ops->set_rsp_status(work, STATUS_INVALID_HANDLE);
 184                 goto send;
 185         }
 186
 187         if (conn->ops->check_user_session) {
 188                 rc = conn->ops->check_user_session(work);
 189                 if (rc < 0) {
 190                         command = conn->ops->get_cmd_val(work);
 191                         conn->ops->set_rsp_status(work,
 192                                         STATUS_USER_SESSION_DELETED);
 193                         goto send;
 194                 } else if (rc > 0) {
 195                         rc = conn->ops->get_ksmbd_tcon(work);
 196                         if (rc < 0) {
 197                                 conn->ops->set_rsp_status(work,
 198                                         STATUS_NETWORK_NAME_DELETED);
 199                                 goto send;
 200                         }
 201                 }
 202         }
 203
 204         do {
 205                 rc = __process_request(work, conn, &command);
 206                 if (rc == SERVER_HANDLER_ABORT)
 207                         break;
 208
 209                 /*
 210                  * Call smb2_set_rsp_credits() function to set number of credits
 211                  * granted in hdr of smb2 response.
 212                  */
 213                 if (conn->ops->set_rsp_credits) {
 214                         spin_lock(&conn->credits_lock);
 215                         rc = conn->ops->set_rsp_credits(work);
 216                         spin_unlock(&conn->credits_lock);
 217                         if (rc < 0) {
 218                                 conn->ops->set_rsp_status(work,
 219                                         STATUS_INVALID_PARAMETER);
 220                                 goto send;
 221                         }
 222                 }
 223
 224                 if (work->sess &&
 225                     (work->sess->sign || smb3_11_final_sess_setup_resp(work) ||
 226                      conn->ops->is_sign_req(work, command)))
 227                         conn->ops->set_sign_rsp(work);
 228         } while (is_chained_smb2_message(work));
 229
 230         if (work->send_no_response)
 231                 return;
 232
 233 send:
 234         smb3_preauth_hash_rsp(work);
 235         if (work->sess && work->sess->enc && work->encrypted &&
 236             conn->ops->encrypt_resp) {
 237                 rc = conn->ops->encrypt_resp(work);
 238                 if (rc < 0) {
 239                         conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
 240                         goto send;
 241                 }
 242         }
 243
 244         ksmbd_conn_write(work);
 245 }
 246
 247 /**
 248  * handle_ksmbd_work() - process pending smb work requests
 249  * @wk: smb work containing request command buffer
 250  *
 251  * called by kworker threads to processing remaining smb work requests
 252  */
 253 static void handle_ksmbd_work(struct work_struct *wk)
 254 {
 255         struct ksmbd_work *work = container_of(wk, struct ksmbd_work, work);
 256         struct ksmbd_conn *conn = work->conn;
 257
 258         atomic64_inc(&conn->stats.request_served);
 259
 260         __handle_ksmbd_work(work, conn);
 261
 262         ksmbd_conn_try_dequeue_request(work);
 263         ksmbd_free_work_struct(work);
 264         /*
 265          * Checking waitqueue to dropping pending requests on
 266          * disconnection. waitqueue_active is safe because it
 267          * uses atomic operation for condition.
 268          */
 269         if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
 270                 wake_up(&conn->r_count_q);
 271 }
 272
 273 /**
 274  * queue_ksmbd_work() - queue a smb request to worker thread queue
 275  *              for proccessing smb command and sending response
 276  * @conn:       connection instance
 277  *
 278  * read remaining data from socket create and submit work.
 279  */
 280 static int queue_ksmbd_work(struct ksmbd_conn *conn)
 281 {
 282         struct ksmbd_work *work;
 283
 284         work = ksmbd_alloc_work_struct();
 285         if (!work) {
 286                 pr_err("allocation for work failed\n");
 287                 return -ENOMEM;
 288         }
 289
 290         work->conn = conn;
 291         work->request_buf = conn->request_buf;
 292         conn->request_buf = NULL;
 293
 294         if (ksmbd_init_smb_server(work)) {
 295                 ksmbd_free_work_struct(work);
 296                 return -EINVAL;
 297         }
 298
 299         ksmbd_conn_enqueue_request(work);
 300         atomic_inc(&conn->r_count);
 301         /* update activity on connection */
 302         conn->last_active = jiffies;
 303         INIT_WORK(&work->work, handle_ksmbd_work);
 304         ksmbd_queue_work(work);
 305         return 0;
 306 }
 307
 308 static int ksmbd_server_process_request(struct ksmbd_conn *conn)
 309 {
 310         return queue_ksmbd_work(conn);
 311 }
 312
 313 static int ksmbd_server_terminate_conn(struct ksmbd_conn *conn)
 314 {
 315         ksmbd_sessions_deregister(conn);
 316         destroy_lease_table(conn);
 317         return 0;
 318 }
 319
 320 static void ksmbd_server_tcp_callbacks_init(void)
 321 {
 322         struct ksmbd_conn_ops ops;
 323
 324         ops.process_fn = ksmbd_server_process_request;
 325         ops.terminate_fn = ksmbd_server_terminate_conn;
 326
 327         ksmbd_conn_init_server_callbacks(&ops);
 328 }
 329
 330 static void server_conf_free(void)
 331 {
 332         int i;
 333
 334         for (i = 0; i < ARRAY_SIZE(server_conf.conf); i++) {
 335                 kfree(server_conf.conf[i]);
 336                 server_conf.conf[i] = NULL;
 337         }
 338 }
 339
 340 static int server_conf_init(void)
 341 {
 342         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 343         server_conf.enforced_signing = 0;
 344         server_conf.min_protocol = ksmbd_min_protocol();
 345         server_conf.max_protocol = ksmbd_max_protocol();
 346         server_conf.auth_mechs = KSMBD_AUTH_NTLMSSP;
 347 #ifdef CONFIG_SMB_SERVER_KERBEROS5
 348         server_conf.auth_mechs |= KSMBD_AUTH_KRB5 |
 349                                 KSMBD_AUTH_MSKRB5;
 350 #endif
 351         return 0;
 352 }
 353
 354 static void server_ctrl_handle_init(struct server_ctrl_struct *ctrl)
 355 {
 356         int ret;
 357
 358         ret = ksmbd_conn_transport_init();
 359         if (ret) {
 360                 server_queue_ctrl_reset_work();
 361                 return;
 362         }
 363
 364         WRITE_ONCE(server_conf.state, SERVER_STATE_RUNNING);
 365 }
 366
 367 static void server_ctrl_handle_reset(struct server_ctrl_struct *ctrl)
 368 {
 369         ksmbd_ipc_soft_reset();
 370         ksmbd_conn_transport_destroy();
 371         server_conf_free();
 372         server_conf_init();
 373         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 374 }
 375
 376 static void server_ctrl_handle_work(struct work_struct *work)
 377 {
 378         struct server_ctrl_struct *ctrl;
 379
 380         ctrl = container_of(work, struct server_ctrl_struct, ctrl_work);
 381
 382         mutex_lock(&ctrl_lock);
 383         switch (ctrl->type) {
 384         case SERVER_CTRL_TYPE_INIT:
 385                 server_ctrl_handle_init(ctrl);
 386                 break;
 387         case SERVER_CTRL_TYPE_RESET:
 388                 server_ctrl_handle_reset(ctrl);
 389                 break;
 390         default:
 391                 pr_err("Unknown server work type: %d\n", ctrl->type);
 392         }
 393         mutex_unlock(&ctrl_lock);
 394         kfree(ctrl);
 395         module_put(THIS_MODULE);
 396 }
 397
 398 static int __queue_ctrl_work(int type)
 399 {
 400         struct server_ctrl_struct *ctrl;
 401
 402         ctrl = kmalloc(sizeof(struct server_ctrl_struct), GFP_KERNEL);
 403         if (!ctrl)
 404                 return -ENOMEM;
 405
 406         __module_get(THIS_MODULE);
 407         ctrl->type = type;
 408         INIT_WORK(&ctrl->ctrl_work, server_ctrl_handle_work);
 409         queue_work(system_long_wq, &ctrl->ctrl_work);
 410         return 0;
 411 }
 412
 413 int server_queue_ctrl_init_work(void)
 414 {
 415         return __queue_ctrl_work(SERVER_CTRL_TYPE_INIT);
 416 }
 417
 418 int server_queue_ctrl_reset_work(void)
 419 {
 420         return __queue_ctrl_work(SERVER_CTRL_TYPE_RESET);
 421 }
 422
 423 static ssize_t stats_show(struct class *class, struct class_attribute *attr,
 424                           char *buf)
 425 {
 426         /*
 427          * Inc this each time you change stats output format,
 428          * so user space will know what to do.
 429          */
 430         static int stats_version = 2;
 431         static const char * const state[] = {
 432                 "startup",
 433                 "running",
 434                 "reset",
 435                 "shutdown"
 436         };
 437
 438         ssize_t sz = scnprintf(buf, PAGE_SIZE, "%d %s %d %lu\n", stats_version,
 439                                state[server_conf.state], server_conf.tcp_port,
 440                                server_conf.ipc_last_active / HZ);
 441         return sz;
 442 }
 443
 444 static ssize_t kill_server_store(struct class *class,
 445                                  struct class_attribute *attr, const char *buf,
 446                                  size_t len)
 447 {
 448         if (!sysfs_streq(buf, "hard"))
 449                 return len;
 450
 451         pr_info("kill command received\n");
 452         mutex_lock(&ctrl_lock);
 453         WRITE_ONCE(server_conf.state, SERVER_STATE_RESETTING);
 454         __module_get(THIS_MODULE);
 455         server_ctrl_handle_reset(NULL);
 456         module_put(THIS_MODULE);
 457         mutex_unlock(&ctrl_lock);
 458         return len;
 459 }
 460
 461 static const char * const debug_type_strings[] = {"smb", "auth", "vfs",
 462                                                   "oplock", "ipc", "conn",
 463                                                   "rdma"};
 464
 465 static ssize_t debug_show(struct class *class, struct class_attribute *attr,
 466                           char *buf)
 467 {
 468         ssize_t sz = 0;
 469         int i, pos = 0;
 470
 471         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 472                 if ((ksmbd_debug_types >> i) & 1) {
 473                         pos = scnprintf(buf + sz,
 474                                         PAGE_SIZE - sz,
 475                                         "[%s] ",
 476                                         debug_type_strings[i]);
 477                 } else {
 478                         pos = scnprintf(buf + sz,
 479                                         PAGE_SIZE - sz,
 480                                         "%s ",
 481                                         debug_type_strings[i]);
 482                 }
 483                 sz += pos;
 484         }
 485         sz += scnprintf(buf + sz, PAGE_SIZE - sz, "\n");
 486         return sz;
 487 }
 488
 489 static ssize_t debug_store(struct class *class, struct class_attribute *attr,
 490                            const char *buf, size_t len)
 491 {
 492         int i;
 493
 494         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 495                 if (sysfs_streq(buf, "all")) {
 496                         if (ksmbd_debug_types == KSMBD_DEBUG_ALL)
 497                                 ksmbd_debug_types = 0;
 498                         else
 499                                 ksmbd_debug_types = KSMBD_DEBUG_ALL;
 500                         break;
 501                 }
 502
 503                 if (sysfs_streq(buf, debug_type_strings[i])) {
 504                         if (ksmbd_debug_types & (1 << i))
 505                                 ksmbd_debug_types &= ~(1 << i);
 506                         else
 507                                 ksmbd_debug_types |= (1 << i);
 508                         break;
 509                 }
 510         }
 511
 512         return len;
 513 }
 514
 515 static CLASS_ATTR_RO(stats);
 516 static CLASS_ATTR_WO(kill_server);
 517 static CLASS_ATTR_RW(debug);
 518
 519 static struct attribute *ksmbd_control_class_attrs[] = {
 520         &class_attr_stats.attr,
 521         &class_attr_kill_server.attr,
 522         &class_attr_debug.attr,
 523         NULL,
 524 };
 525 ATTRIBUTE_GROUPS(ksmbd_control_class);
 526
 527 static struct class ksmbd_control_class = {
 528         .name           = "ksmbd-control",
 529         .owner          = THIS_MODULE,
 530         .class_groups   = ksmbd_control_class_groups,
 531 };
 532
 533 static int ksmbd_server_shutdown(void)
 534 {
 535         WRITE_ONCE(server_conf.state, SERVER_STATE_SHUTTING_DOWN);
 536
 537         class_unregister(&ksmbd_control_class);
 538         ksmbd_workqueue_destroy();
 539         ksmbd_ipc_release();
 540         ksmbd_conn_transport_destroy();
 541         ksmbd_crypto_destroy();
 542         ksmbd_free_global_file_table();
 543         destroy_lease_table(NULL);
 544         ksmbd_work_pool_destroy();
 545         ksmbd_exit_file_cache();
 546         server_conf_free();
 547         return 0;
 548 }
 549
 550 static int __init ksmbd_server_init(void)
 551 {
 552         int ret;
 553
 554         ret = class_register(&ksmbd_control_class);
 555         if (ret) {
 556                 pr_err("Unable to register ksmbd-control class\n");
 557                 return ret;
 558         }
 559
 560         ksmbd_server_tcp_callbacks_init();
 561
 562         ret = server_conf_init();
 563         if (ret)
 564                 goto err_unregister;
 565
 566         ret = ksmbd_work_pool_init();
 567         if (ret)
 568                 goto err_unregister;
 569
 570         ret = ksmbd_init_file_cache();
 571         if (ret)
 572                 goto err_destroy_work_pools;
 573
 574         ret = ksmbd_ipc_init();
 575         if (ret)
 576                 goto err_exit_file_cache;
 577
 578         ret = ksmbd_init_global_file_table();
 579         if (ret)
 580                 goto err_ipc_release;
 581
 582         ret = ksmbd_inode_hash_init();
 583         if (ret)
 584                 goto err_destroy_file_table;
 585
 586         ret = ksmbd_crypto_create();
 587         if (ret)
 588                 goto err_release_inode_hash;
 589
 590         ret = ksmbd_workqueue_init();
 591         if (ret)
 592                 goto err_crypto_destroy;
 593
 594         pr_warn_once("The ksmbd server is experimental\n");
 595
 596         return 0;
 597
 598 err_crypto_destroy:
 599         ksmbd_crypto_destroy();
 600 err_release_inode_hash:
 601         ksmbd_release_inode_hash();
 602 err_destroy_file_table:
 603         ksmbd_free_global_file_table();
 604 err_ipc_release:
 605         ksmbd_ipc_release();
 606 err_exit_file_cache:
 607         ksmbd_exit_file_cache();
 608 err_destroy_work_pools:
 609         ksmbd_work_pool_destroy();
 610 err_unregister:
 611         class_unregister(&ksmbd_control_class);
 612
 613         return ret;
 614 }
 615
 616 /**
 617  * ksmbd_server_exit() - shutdown forker thread and free memory at module exit
 618  */
 619 static void __exit ksmbd_server_exit(void)
 620 {
 621         ksmbd_server_shutdown();
 622         ksmbd_release_inode_hash();
 623 }
 624
 625 MODULE_AUTHOR("Namjae Jeon <linkinjeon@kernel.org>");
 626 MODULE_VERSION(KSMBD_VERSION);
 627 MODULE_DESCRIPTION("Linux kernel CIFS/SMB SERVER");
 628 MODULE_LICENSE("GPL");
 629 MODULE_SOFTDEP("pre: ecb");
 630 MODULE_SOFTDEP("pre: hmac");
 631 MODULE_SOFTDEP("pre: md5");
 632 MODULE_SOFTDEP("pre: nls");
 633 MODULE_SOFTDEP("pre: aes");
 634 MODULE_SOFTDEP("pre: cmac");
 635 MODULE_SOFTDEP("pre: sha256");
 636 MODULE_SOFTDEP("pre: sha512");
 637 MODULE_SOFTDEP("pre: aead2");
 638 MODULE_SOFTDEP("pre: ccm");
 639 MODULE_SOFTDEP("pre: gcm");
 640 MODULE_SOFTDEP("pre: crc32");
 641 module_init(ksmbd_server_init)
 642 module_exit(ksmbd_server_exit)