fs/smb/server/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->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                 return SERVER_HANDLER_ABORT;
 120
 121         command = conn->ops->get_cmd_val(work);
 122         *cmd = command;
 123
 124 andx_again:
 125         if (command >= conn->max_cmds) {
 126                 conn->ops->set_rsp_status(work, STATUS_INVALID_PARAMETER);
 127                 return SERVER_HANDLER_CONTINUE;
 128         }
 129
 130         cmds = &conn->cmds[command];
 131         if (!cmds->proc) {
 132                 ksmbd_debug(SMB, "*** not implemented yet cmd = %x\n", command);
 133                 conn->ops->set_rsp_status(work, STATUS_NOT_IMPLEMENTED);
 134                 return SERVER_HANDLER_CONTINUE;
 135         }
 136
 137         if (work->sess && conn->ops->is_sign_req(work, command)) {
 138                 ret = conn->ops->check_sign_req(work);
 139                 if (!ret) {
 140                         conn->ops->set_rsp_status(work, STATUS_ACCESS_DENIED);
 141                         return SERVER_HANDLER_CONTINUE;
 142                 }
 143         }
 144
 145         ret = cmds->proc(work);
 146
 147         if (ret < 0)
 148                 ksmbd_debug(CONN, "Failed to process %u [%d]\n", command, ret);
 149         /* AndX commands - chained request can return positive values */
 150         else if (ret > 0) {
 151                 command = ret;
 152                 *cmd = command;
 153                 goto andx_again;
 154         }
 155
 156         if (work->send_no_response)
 157                 return SERVER_HANDLER_ABORT;
 158         return SERVER_HANDLER_CONTINUE;
 159 }
 160
 161 static void __handle_ksmbd_work(struct ksmbd_work *work,
 162                                 struct ksmbd_conn *conn)
 163 {
 164         u16 command = 0;
 165         int rc;
 166
 167         if (conn->ops->allocate_rsp_buf(work))
 168                 return;
 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                         conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
 175                         goto send;
 176                 }
 177
 178                 work->encrypted = true;
 179         }
 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                 if (work->sess &&
 233                     (work->sess->sign || smb3_11_final_sess_setup_resp(work) ||
 234                      conn->ops->is_sign_req(work, command)))
 235                         conn->ops->set_sign_rsp(work);
 236         } while (is_chained_smb2_message(work));
 237
 238         if (work->send_no_response)
 239                 return;
 240
 241 send:
 242         smb3_preauth_hash_rsp(work);
 243         if (work->sess && work->sess->enc && work->encrypted &&
 244             conn->ops->encrypt_resp) {
 245                 rc = conn->ops->encrypt_resp(work);
 246                 if (rc < 0)
 247                         conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
 248         }
 249
 250         ksmbd_conn_write(work);
 251 }
 252
 253 /**
 254  * handle_ksmbd_work() - process pending smb work requests
 255  * @wk: smb work containing request command buffer
 256  *
 257  * called by kworker threads to processing remaining smb work requests
 258  */
 259 static void handle_ksmbd_work(struct work_struct *wk)
 260 {
 261         struct ksmbd_work *work = container_of(wk, struct ksmbd_work, work);
 262         struct ksmbd_conn *conn = work->conn;
 263
 264         atomic64_inc(&conn->stats.request_served);
 265
 266         __handle_ksmbd_work(work, conn);
 267
 268         ksmbd_conn_try_dequeue_request(work);
 269         ksmbd_free_work_struct(work);
 270         /*
 271          * Checking waitqueue to dropping pending requests on
 272          * disconnection. waitqueue_active is safe because it
 273          * uses atomic operation for condition.
 274          */
 275         if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
 276                 wake_up(&conn->r_count_q);
 277 }
 278
 279 /**
 280  * queue_ksmbd_work() - queue a smb request to worker thread queue
 281  *              for proccessing smb command and sending response
 282  * @conn:       connection instance
 283  *
 284  * read remaining data from socket create and submit work.
 285  */
 286 static int queue_ksmbd_work(struct ksmbd_conn *conn)
 287 {
 288         struct ksmbd_work *work;
 289         int err;
 290
 291         work = ksmbd_alloc_work_struct();
 292         if (!work) {
 293                 pr_err("allocation for work failed\n");
 294                 return -ENOMEM;
 295         }
 296
 297         work->conn = conn;
 298         work->request_buf = conn->request_buf;
 299         conn->request_buf = NULL;
 300
 301         err = ksmbd_init_smb_server(work);
 302         if (err) {
 303                 ksmbd_free_work_struct(work);
 304                 return 0;
 305         }
 306
 307         ksmbd_conn_enqueue_request(work);
 308         atomic_inc(&conn->r_count);
 309         /* update activity on connection */
 310         conn->last_active = jiffies;
 311         INIT_WORK(&work->work, handle_ksmbd_work);
 312         ksmbd_queue_work(work);
 313         return 0;
 314 }
 315
 316 static int ksmbd_server_process_request(struct ksmbd_conn *conn)
 317 {
 318         return queue_ksmbd_work(conn);
 319 }
 320
 321 static int ksmbd_server_terminate_conn(struct ksmbd_conn *conn)
 322 {
 323         ksmbd_sessions_deregister(conn);
 324         destroy_lease_table(conn);
 325         return 0;
 326 }
 327
 328 static void ksmbd_server_tcp_callbacks_init(void)
 329 {
 330         struct ksmbd_conn_ops ops;
 331
 332         ops.process_fn = ksmbd_server_process_request;
 333         ops.terminate_fn = ksmbd_server_terminate_conn;
 334
 335         ksmbd_conn_init_server_callbacks(&ops);
 336 }
 337
 338 static void server_conf_free(void)
 339 {
 340         int i;
 341
 342         for (i = 0; i < ARRAY_SIZE(server_conf.conf); i++) {
 343                 kfree(server_conf.conf[i]);
 344                 server_conf.conf[i] = NULL;
 345         }
 346 }
 347
 348 static int server_conf_init(void)
 349 {
 350         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 351         server_conf.enforced_signing = 0;
 352         server_conf.min_protocol = ksmbd_min_protocol();
 353         server_conf.max_protocol = ksmbd_max_protocol();
 354         server_conf.auth_mechs = KSMBD_AUTH_NTLMSSP;
 355 #ifdef CONFIG_SMB_SERVER_KERBEROS5
 356         server_conf.auth_mechs |= KSMBD_AUTH_KRB5 |
 357                                 KSMBD_AUTH_MSKRB5;
 358 #endif
 359         return 0;
 360 }
 361
 362 static void server_ctrl_handle_init(struct server_ctrl_struct *ctrl)
 363 {
 364         int ret;
 365
 366         ret = ksmbd_conn_transport_init();
 367         if (ret) {
 368                 server_queue_ctrl_reset_work();
 369                 return;
 370         }
 371
 372         WRITE_ONCE(server_conf.state, SERVER_STATE_RUNNING);
 373 }
 374
 375 static void server_ctrl_handle_reset(struct server_ctrl_struct *ctrl)
 376 {
 377         ksmbd_ipc_soft_reset();
 378         ksmbd_conn_transport_destroy();
 379         server_conf_free();
 380         server_conf_init();
 381         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 382 }
 383
 384 static void server_ctrl_handle_work(struct work_struct *work)
 385 {
 386         struct server_ctrl_struct *ctrl;
 387
 388         ctrl = container_of(work, struct server_ctrl_struct, ctrl_work);
 389
 390         mutex_lock(&ctrl_lock);
 391         switch (ctrl->type) {
 392         case SERVER_CTRL_TYPE_INIT:
 393                 server_ctrl_handle_init(ctrl);
 394                 break;
 395         case SERVER_CTRL_TYPE_RESET:
 396                 server_ctrl_handle_reset(ctrl);
 397                 break;
 398         default:
 399                 pr_err("Unknown server work type: %d\n", ctrl->type);
 400         }
 401         mutex_unlock(&ctrl_lock);
 402         kfree(ctrl);
 403         module_put(THIS_MODULE);
 404 }
 405
 406 static int __queue_ctrl_work(int type)
 407 {
 408         struct server_ctrl_struct *ctrl;
 409
 410         ctrl = kmalloc(sizeof(struct server_ctrl_struct), GFP_KERNEL);
 411         if (!ctrl)
 412                 return -ENOMEM;
 413
 414         __module_get(THIS_MODULE);
 415         ctrl->type = type;
 416         INIT_WORK(&ctrl->ctrl_work, server_ctrl_handle_work);
 417         queue_work(system_long_wq, &ctrl->ctrl_work);
 418         return 0;
 419 }
 420
 421 int server_queue_ctrl_init_work(void)
 422 {
 423         return __queue_ctrl_work(SERVER_CTRL_TYPE_INIT);
 424 }
 425
 426 int server_queue_ctrl_reset_work(void)
 427 {
 428         return __queue_ctrl_work(SERVER_CTRL_TYPE_RESET);
 429 }
 430
 431 static ssize_t stats_show(const struct class *class, const struct class_attribute *attr,
 432                           char *buf)
 433 {
 434         /*
 435          * Inc this each time you change stats output format,
 436          * so user space will know what to do.
 437          */
 438         static int stats_version = 2;
 439         static const char * const state[] = {
 440                 "startup",
 441                 "running",
 442                 "reset",
 443                 "shutdown"
 444         };
 445         return sysfs_emit(buf, "%d %s %d %lu\n", stats_version,
 446                           state[server_conf.state], server_conf.tcp_port,
 447                           server_conf.ipc_last_active / HZ);
 448 }
 449
 450 static ssize_t kill_server_store(const struct class *class,
 451                                  const struct class_attribute *attr, const char *buf,
 452                                  size_t len)
 453 {
 454         if (!sysfs_streq(buf, "hard"))
 455                 return len;
 456
 457         pr_info("kill command received\n");
 458         mutex_lock(&ctrl_lock);
 459         WRITE_ONCE(server_conf.state, SERVER_STATE_RESETTING);
 460         __module_get(THIS_MODULE);
 461         server_ctrl_handle_reset(NULL);
 462         module_put(THIS_MODULE);
 463         mutex_unlock(&ctrl_lock);
 464         return len;
 465 }
 466
 467 static const char * const debug_type_strings[] = {"smb", "auth", "vfs",
 468                                                   "oplock", "ipc", "conn",
 469                                                   "rdma"};
 470
 471 static ssize_t debug_show(const struct class *class, const struct class_attribute *attr,
 472                           char *buf)
 473 {
 474         ssize_t sz = 0;
 475         int i, pos = 0;
 476
 477         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 478                 if ((ksmbd_debug_types >> i) & 1) {
 479                         pos = sysfs_emit_at(buf, sz, "[%s] ", debug_type_strings[i]);
 480                 } else {
 481                         pos = sysfs_emit_at(buf, sz, "%s ", debug_type_strings[i]);
 482                 }
 483                 sz += pos;
 484         }
 485         sz += sysfs_emit_at(buf, sz, "\n");
 486         return sz;
 487 }
 488
 489 static ssize_t debug_store(const struct class *class, const 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         .class_groups   = ksmbd_control_class_groups,
 530 };
 531
 532 static int ksmbd_server_shutdown(void)
 533 {
 534         WRITE_ONCE(server_conf.state, SERVER_STATE_SHUTTING_DOWN);
 535
 536         class_unregister(&ksmbd_control_class);
 537         ksmbd_workqueue_destroy();
 538         ksmbd_ipc_release();
 539         ksmbd_conn_transport_destroy();
 540         ksmbd_crypto_destroy();
 541         ksmbd_free_global_file_table();
 542         destroy_lease_table(NULL);
 543         ksmbd_work_pool_destroy();
 544         ksmbd_exit_file_cache();
 545         server_conf_free();
 546         return 0;
 547 }
 548
 549 static int __init ksmbd_server_init(void)
 550 {
 551         int ret;
 552
 553         ret = class_register(&ksmbd_control_class);
 554         if (ret) {
 555                 pr_err("Unable to register ksmbd-control class\n");
 556                 return ret;
 557         }
 558
 559         ksmbd_server_tcp_callbacks_init();
 560
 561         ret = server_conf_init();
 562         if (ret)
 563                 goto err_unregister;
 564
 565         ret = ksmbd_work_pool_init();
 566         if (ret)
 567                 goto err_unregister;
 568
 569         ret = ksmbd_init_file_cache();
 570         if (ret)
 571                 goto err_destroy_work_pools;
 572
 573         ret = ksmbd_ipc_init();
 574         if (ret)
 575                 goto err_exit_file_cache;
 576
 577         ret = ksmbd_init_global_file_table();
 578         if (ret)
 579                 goto err_ipc_release;
 580
 581         ret = ksmbd_inode_hash_init();
 582         if (ret)
 583                 goto err_destroy_file_table;
 584
 585         ret = ksmbd_crypto_create();
 586         if (ret)
 587                 goto err_release_inode_hash;
 588
 589         ret = ksmbd_workqueue_init();
 590         if (ret)
 591                 goto err_crypto_destroy;
 592
 593         pr_warn_once("The ksmbd server is experimental\n");
 594
 595         return 0;
 596
 597 err_crypto_destroy:
 598         ksmbd_crypto_destroy();
 599 err_release_inode_hash:
 600         ksmbd_release_inode_hash();
 601 err_destroy_file_table:
 602         ksmbd_free_global_file_table();
 603 err_ipc_release:
 604         ksmbd_ipc_release();
 605 err_exit_file_cache:
 606         ksmbd_exit_file_cache();
 607 err_destroy_work_pools:
 608         ksmbd_work_pool_destroy();
 609 err_unregister:
 610         class_unregister(&ksmbd_control_class);
 611
 612         return ret;
 613 }
 614
 615 /**
 616  * ksmbd_server_exit() - shutdown forker thread and free memory at module exit
 617  */
 618 static void __exit ksmbd_server_exit(void)
 619 {
 620         ksmbd_server_shutdown();
 621         rcu_barrier();
 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)