fs/smb/server/server.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   Copyright (C) 2016 Namjae Jeon <[email protected]>
   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->conn) ||
  97             ksmbd_conn_need_reconnect(work->conn)) {
  98                 rsp_hdr = work->response_buf;
  99                 rsp_hdr->Status.CifsError = STATUS_CONNECTION_DISCONNECTED;
 100                 return 1;
 101         }
 102         return 0;
 103 }
 104
 105 #define SERVER_HANDLER_CONTINUE         0
 106 #define SERVER_HANDLER_ABORT            1
 107
 108 static int __process_request(struct ksmbd_work *work, struct ksmbd_conn *conn,
 109                              u16 *cmd)
 110 {
 111         struct smb_version_cmds *cmds;
 112         u16 command;
 113         int ret;
 114
 115         if (check_conn_state(work))
 116                 return SERVER_HANDLER_CONTINUE;
 117
 118         if (ksmbd_verify_smb_message(work)) {
 119                 conn->ops->set_rsp_status(work, STATUS_INVALID_PARAMETER);
 120                 return SERVER_HANDLER_ABORT;
 121         }
 122
 123         command = conn->ops->get_cmd_val(work);
 124         *cmd = command;
 125
 126 andx_again:
 127         if (command >= conn->max_cmds) {
 128                 conn->ops->set_rsp_status(work, STATUS_INVALID_PARAMETER);
 129                 return SERVER_HANDLER_CONTINUE;
 130         }
 131
 132         cmds = &conn->cmds[command];
 133         if (!cmds->proc) {
 134                 ksmbd_debug(SMB, "*** not implemented yet cmd = %x\n", command);
 135                 conn->ops->set_rsp_status(work, STATUS_NOT_IMPLEMENTED);
 136                 return SERVER_HANDLER_CONTINUE;
 137         }
 138
 139         if (work->sess && conn->ops->is_sign_req(work, command)) {
 140                 ret = conn->ops->check_sign_req(work);
 141                 if (!ret) {
 142                         conn->ops->set_rsp_status(work, STATUS_ACCESS_DENIED);
 143                         return SERVER_HANDLER_CONTINUE;
 144                 }
 145         }
 146
 147         ret = cmds->proc(work);
 148
 149         if (ret < 0)
 150                 ksmbd_debug(CONN, "Failed to process %u [%d]\n", command, ret);
 151         /* AndX commands - chained request can return positive values */
 152         else if (ret > 0) {
 153                 command = ret;
 154                 *cmd = command;
 155                 goto andx_again;
 156         }
 157
 158         if (work->send_no_response)
 159                 return SERVER_HANDLER_ABORT;
 160         return SERVER_HANDLER_CONTINUE;
 161 }
 162
 163 static void __handle_ksmbd_work(struct ksmbd_work *work,
 164                                 struct ksmbd_conn *conn)
 165 {
 166         u16 command = 0;
 167         int rc;
 168         bool is_chained = false;
 169
 170         if (conn->ops->is_transform_hdr &&
 171             conn->ops->is_transform_hdr(work->request_buf)) {
 172                 rc = conn->ops->decrypt_req(work);
 173                 if (rc < 0)
 174                         return;
 175                 work->encrypted = true;
 176         }
 177
 178         if (conn->ops->allocate_rsp_buf(work))
 179                 return;
 180
 181         rc = conn->ops->init_rsp_hdr(work);
 182         if (rc) {
 183                 /* either uid or tid is not correct */
 184                 conn->ops->set_rsp_status(work, STATUS_INVALID_HANDLE);
 185                 goto send;
 186         }
 187
 188         do {
 189                 if (conn->ops->check_user_session) {
 190                         rc = conn->ops->check_user_session(work);
 191                         if (rc < 0) {
 192                                 if (rc == -EINVAL)
 193                                         conn->ops->set_rsp_status(work,
 194                                                 STATUS_INVALID_PARAMETER);
 195                                 else
 196                                         conn->ops->set_rsp_status(work,
 197                                                 STATUS_USER_SESSION_DELETED);
 198                                 goto send;
 199                         } else if (rc > 0) {
 200                                 rc = conn->ops->get_ksmbd_tcon(work);
 201                                 if (rc < 0) {
 202                                         if (rc == -EINVAL)
 203                                                 conn->ops->set_rsp_status(work,
 204                                                         STATUS_INVALID_PARAMETER);
 205                                         else
 206                                                 conn->ops->set_rsp_status(work,
 207                                                         STATUS_NETWORK_NAME_DELETED);
 208                                         goto send;
 209                                 }
 210                         }
 211                 }
 212
 213                 rc = __process_request(work, conn, &command);
 214                 if (rc == SERVER_HANDLER_ABORT)
 215                         break;
 216
 217                 /*
 218                  * Call smb2_set_rsp_credits() function to set number of credits
 219                  * granted in hdr of smb2 response.
 220                  */
 221                 if (conn->ops->set_rsp_credits) {
 222                         spin_lock(&conn->credits_lock);
 223                         rc = conn->ops->set_rsp_credits(work);
 224                         spin_unlock(&conn->credits_lock);
 225                         if (rc < 0) {
 226                                 conn->ops->set_rsp_status(work,
 227                                         STATUS_INVALID_PARAMETER);
 228                                 goto send;
 229                         }
 230                 }
 231
 232                 is_chained = is_chained_smb2_message(work);
 233
 234                 if (work->sess &&
 235                     (work->sess->sign || smb3_11_final_sess_setup_resp(work) ||
 236                      conn->ops->is_sign_req(work, command)))
 237                         conn->ops->set_sign_rsp(work);
 238         } while (is_chained == true);
 239
 240 send:
 241         if (work->tcon)
 242                 ksmbd_tree_connect_put(work->tcon);
 243         smb3_preauth_hash_rsp(work);
 244         if (work->sess && work->sess->enc && work->encrypted &&
 245             conn->ops->encrypt_resp) {
 246                 rc = conn->ops->encrypt_resp(work);
 247                 if (rc < 0)
 248                         conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
 249         }
 250
 251         ksmbd_conn_write(work);
 252 }
 253
 254 /**
 255  * handle_ksmbd_work() - process pending smb work requests
 256  * @wk: smb work containing request command buffer
 257  *
 258  * called by kworker threads to processing remaining smb work requests
 259  */
 260 static void handle_ksmbd_work(struct work_struct *wk)
 261 {
 262         struct ksmbd_work *work = container_of(wk, struct ksmbd_work, work);
 263         struct ksmbd_conn *conn = work->conn;
 264
 265         atomic64_inc(&conn->stats.request_served);
 266
 267         __handle_ksmbd_work(work, conn);
 268
 269         ksmbd_conn_try_dequeue_request(work);
 270         ksmbd_free_work_struct(work);
 271         /*
 272          * Checking waitqueue to dropping pending requests on
 273          * disconnection. waitqueue_active is safe because it
 274          * uses atomic operation for condition.
 275          */
 276         if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
 277                 wake_up(&conn->r_count_q);
 278 }
 279
 280 /**
 281  * queue_ksmbd_work() - queue a smb request to worker thread queue
 282  *              for proccessing smb command and sending response
 283  * @conn:       connection instance
 284  *
 285  * read remaining data from socket create and submit work.
 286  */
 287 static int queue_ksmbd_work(struct ksmbd_conn *conn)
 288 {
 289         struct ksmbd_work *work;
 290         int err;
 291
 292         work = ksmbd_alloc_work_struct();
 293         if (!work) {
 294                 pr_err("allocation for work failed\n");
 295                 return -ENOMEM;
 296         }
 297
 298         work->conn = conn;
 299         work->request_buf = conn->request_buf;
 300         conn->request_buf = NULL;
 301
 302         err = ksmbd_init_smb_server(work);
 303         if (err) {
 304                 ksmbd_free_work_struct(work);
 305                 return 0;
 306         }
 307
 308         ksmbd_conn_enqueue_request(work);
 309         atomic_inc(&conn->r_count);
 310         /* update activity on connection */
 311         conn->last_active = jiffies;
 312         INIT_WORK(&work->work, handle_ksmbd_work);
 313         ksmbd_queue_work(work);
 314         return 0;
 315 }
 316
 317 static int ksmbd_server_process_request(struct ksmbd_conn *conn)
 318 {
 319         return queue_ksmbd_work(conn);
 320 }
 321
 322 static int ksmbd_server_terminate_conn(struct ksmbd_conn *conn)
 323 {
 324         ksmbd_sessions_deregister(conn);
 325         destroy_lease_table(conn);
 326         return 0;
 327 }
 328
 329 static void ksmbd_server_tcp_callbacks_init(void)
 330 {
 331         struct ksmbd_conn_ops ops;
 332
 333         ops.process_fn = ksmbd_server_process_request;
 334         ops.terminate_fn = ksmbd_server_terminate_conn;
 335
 336         ksmbd_conn_init_server_callbacks(&ops);
 337 }
 338
 339 static void server_conf_free(void)
 340 {
 341         int i;
 342
 343         for (i = 0; i < ARRAY_SIZE(server_conf.conf); i++) {
 344                 kfree(server_conf.conf[i]);
 345                 server_conf.conf[i] = NULL;
 346         }
 347 }
 348
 349 static int server_conf_init(void)
 350 {
 351         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 352         server_conf.enforced_signing = 0;
 353         server_conf.min_protocol = ksmbd_min_protocol();
 354         server_conf.max_protocol = ksmbd_max_protocol();
 355         server_conf.auth_mechs = KSMBD_AUTH_NTLMSSP;
 356 #ifdef CONFIG_SMB_SERVER_KERBEROS5
 357         server_conf.auth_mechs |= KSMBD_AUTH_KRB5 |
 358                                 KSMBD_AUTH_MSKRB5;
 359 #endif
 360         return 0;
 361 }
 362
 363 static void server_ctrl_handle_init(struct server_ctrl_struct *ctrl)
 364 {
 365         int ret;
 366
 367         ret = ksmbd_conn_transport_init();
 368         if (ret) {
 369                 server_queue_ctrl_reset_work();
 370                 return;
 371         }
 372
 373         WRITE_ONCE(server_conf.state, SERVER_STATE_RUNNING);
 374 }
 375
 376 static void server_ctrl_handle_reset(struct server_ctrl_struct *ctrl)
 377 {
 378         ksmbd_ipc_soft_reset();
 379         ksmbd_conn_transport_destroy();
 380         server_conf_free();
 381         server_conf_init();
 382         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 383 }
 384
 385 static void server_ctrl_handle_work(struct work_struct *work)
 386 {
 387         struct server_ctrl_struct *ctrl;
 388
 389         ctrl = container_of(work, struct server_ctrl_struct, ctrl_work);
 390
 391         mutex_lock(&ctrl_lock);
 392         switch (ctrl->type) {
 393         case SERVER_CTRL_TYPE_INIT:
 394                 server_ctrl_handle_init(ctrl);
 395                 break;
 396         case SERVER_CTRL_TYPE_RESET:
 397                 server_ctrl_handle_reset(ctrl);
 398                 break;
 399         default:
 400                 pr_err("Unknown server work type: %d\n", ctrl->type);
 401         }
 402         mutex_unlock(&ctrl_lock);
 403         kfree(ctrl);
 404         module_put(THIS_MODULE);
 405 }
 406
 407 static int __queue_ctrl_work(int type)
 408 {
 409         struct server_ctrl_struct *ctrl;
 410
 411         ctrl = kmalloc(sizeof(struct server_ctrl_struct), GFP_KERNEL);
 412         if (!ctrl)
 413                 return -ENOMEM;
 414
 415         __module_get(THIS_MODULE);
 416         ctrl->type = type;
 417         INIT_WORK(&ctrl->ctrl_work, server_ctrl_handle_work);
 418         queue_work(system_long_wq, &ctrl->ctrl_work);
 419         return 0;
 420 }
 421
 422 int server_queue_ctrl_init_work(void)
 423 {
 424         return __queue_ctrl_work(SERVER_CTRL_TYPE_INIT);
 425 }
 426
 427 int server_queue_ctrl_reset_work(void)
 428 {
 429         return __queue_ctrl_work(SERVER_CTRL_TYPE_RESET);
 430 }
 431
 432 static ssize_t stats_show(const struct class *class, const struct class_attribute *attr,
 433                           char *buf)
 434 {
 435         /*
 436          * Inc this each time you change stats output format,
 437          * so user space will know what to do.
 438          */
 439         static int stats_version = 2;
 440         static const char * const state[] = {
 441                 "startup",
 442                 "running",
 443                 "reset",
 444                 "shutdown"
 445         };
 446         return sysfs_emit(buf, "%d %s %d %lu\n", stats_version,
 447                           state[server_conf.state], server_conf.tcp_port,
 448                           server_conf.ipc_last_active / HZ);
 449 }
 450
 451 static ssize_t kill_server_store(const struct class *class,
 452                                  const struct class_attribute *attr, const char *buf,
 453                                  size_t len)
 454 {
 455         if (!sysfs_streq(buf, "hard"))
 456                 return len;
 457
 458         pr_info("kill command received\n");
 459         mutex_lock(&ctrl_lock);
 460         WRITE_ONCE(server_conf.state, SERVER_STATE_RESETTING);
 461         __module_get(THIS_MODULE);
 462         server_ctrl_handle_reset(NULL);
 463         module_put(THIS_MODULE);
 464         mutex_unlock(&ctrl_lock);
 465         return len;
 466 }
 467
 468 static const char * const debug_type_strings[] = {"smb", "auth", "vfs",
 469                                                   "oplock", "ipc", "conn",
 470                                                   "rdma"};
 471
 472 static ssize_t debug_show(const struct class *class, const struct class_attribute *attr,
 473                           char *buf)
 474 {
 475         ssize_t sz = 0;
 476         int i, pos = 0;
 477
 478         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 479                 if ((ksmbd_debug_types >> i) & 1) {
 480                         pos = sysfs_emit_at(buf, sz, "[%s] ", debug_type_strings[i]);
 481                 } else {
 482                         pos = sysfs_emit_at(buf, sz, "%s ", debug_type_strings[i]);
 483                 }
 484                 sz += pos;
 485         }
 486         sz += sysfs_emit_at(buf, sz, "\n");
 487         return sz;
 488 }
 489
 490 static ssize_t debug_store(const struct class *class, const struct class_attribute *attr,
 491                            const char *buf, size_t len)
 492 {
 493         int i;
 494
 495         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 496                 if (sysfs_streq(buf, "all")) {
 497                         if (ksmbd_debug_types == KSMBD_DEBUG_ALL)
 498                                 ksmbd_debug_types = 0;
 499                         else
 500                                 ksmbd_debug_types = KSMBD_DEBUG_ALL;
 501                         break;
 502                 }
 503
 504                 if (sysfs_streq(buf, debug_type_strings[i])) {
 505                         if (ksmbd_debug_types & (1 << i))
 506                                 ksmbd_debug_types &= ~(1 << i);
 507                         else
 508                                 ksmbd_debug_types |= (1 << i);
 509                         break;
 510                 }
 511         }
 512
 513         return len;
 514 }
 515
 516 static CLASS_ATTR_RO(stats);
 517 static CLASS_ATTR_WO(kill_server);
 518 static CLASS_ATTR_RW(debug);
 519
 520 static struct attribute *ksmbd_control_class_attrs[] = {
 521         &class_attr_stats.attr,
 522         &class_attr_kill_server.attr,
 523         &class_attr_debug.attr,
 524         NULL,
 525 };
 526 ATTRIBUTE_GROUPS(ksmbd_control_class);
 527
 528 static struct class ksmbd_control_class = {
 529         .name           = "ksmbd-control",
 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         return 0;
 595
 596 err_crypto_destroy:
 597         ksmbd_crypto_destroy();
 598 err_release_inode_hash:
 599         ksmbd_release_inode_hash();
 600 err_destroy_file_table:
 601         ksmbd_free_global_file_table();
 602 err_ipc_release:
 603         ksmbd_ipc_release();
 604 err_exit_file_cache:
 605         ksmbd_exit_file_cache();
 606 err_destroy_work_pools:
 607         ksmbd_work_pool_destroy();
 608 err_unregister:
 609         class_unregister(&ksmbd_control_class);
 610
 611         return ret;
 612 }
 613
 614 /**
 615  * ksmbd_server_exit() - shutdown forker thread and free memory at module exit
 616  */
 617 static void __exit ksmbd_server_exit(void)
 618 {
 619         ksmbd_server_shutdown();
 620         rcu_barrier();
 621         ksmbd_release_inode_hash();
 622 }
 623
 624 MODULE_AUTHOR("Namjae Jeon <[email protected]>");
 625 MODULE_DESCRIPTION("Linux kernel CIFS/SMB SERVER");
 626 MODULE_LICENSE("GPL");
 627 MODULE_SOFTDEP("pre: ecb");
 628 MODULE_SOFTDEP("pre: hmac");
 629 MODULE_SOFTDEP("pre: md5");
 630 MODULE_SOFTDEP("pre: nls");
 631 MODULE_SOFTDEP("pre: aes");
 632 MODULE_SOFTDEP("pre: cmac");
 633 MODULE_SOFTDEP("pre: sha256");
 634 MODULE_SOFTDEP("pre: sha512");
 635 MODULE_SOFTDEP("pre: aead2");
 636 MODULE_SOFTDEP("pre: ccm");
 637 MODULE_SOFTDEP("pre: gcm");
 638 MODULE_SOFTDEP("pre: crc32");
 639 module_init(ksmbd_server_init)
 640 module_exit(ksmbd_server_exit)