fs/ksmbd/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) || 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         atomic_dec(&conn->r_count);
 265 }
 266
 267 /**
 268  * queue_ksmbd_work() - queue a smb request to worker thread queue
 269  *              for proccessing smb command and sending response
 270  * @conn:       connection instance
 271  *
 272  * read remaining data from socket create and submit work.
 273  */
 274 static int queue_ksmbd_work(struct ksmbd_conn *conn)
 275 {
 276         struct ksmbd_work *work;
 277
 278         work = ksmbd_alloc_work_struct();
 279         if (!work) {
 280                 pr_err("allocation for work failed\n");
 281                 return -ENOMEM;
 282         }
 283
 284         work->conn = conn;
 285         work->request_buf = conn->request_buf;
 286         conn->request_buf = NULL;
 287
 288         if (ksmbd_init_smb_server(work)) {
 289                 ksmbd_free_work_struct(work);
 290                 return -EINVAL;
 291         }
 292
 293         ksmbd_conn_enqueue_request(work);
 294         atomic_inc(&conn->r_count);
 295         /* update activity on connection */
 296         conn->last_active = jiffies;
 297         INIT_WORK(&work->work, handle_ksmbd_work);
 298         ksmbd_queue_work(work);
 299         return 0;
 300 }
 301
 302 static int ksmbd_server_process_request(struct ksmbd_conn *conn)
 303 {
 304         return queue_ksmbd_work(conn);
 305 }
 306
 307 static int ksmbd_server_terminate_conn(struct ksmbd_conn *conn)
 308 {
 309         ksmbd_sessions_deregister(conn);
 310         destroy_lease_table(conn);
 311         return 0;
 312 }
 313
 314 static void ksmbd_server_tcp_callbacks_init(void)
 315 {
 316         struct ksmbd_conn_ops ops;
 317
 318         ops.process_fn = ksmbd_server_process_request;
 319         ops.terminate_fn = ksmbd_server_terminate_conn;
 320
 321         ksmbd_conn_init_server_callbacks(&ops);
 322 }
 323
 324 static void server_conf_free(void)
 325 {
 326         int i;
 327
 328         for (i = 0; i < ARRAY_SIZE(server_conf.conf); i++) {
 329                 kfree(server_conf.conf[i]);
 330                 server_conf.conf[i] = NULL;
 331         }
 332 }
 333
 334 static int server_conf_init(void)
 335 {
 336         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 337         server_conf.enforced_signing = 0;
 338         server_conf.min_protocol = ksmbd_min_protocol();
 339         server_conf.max_protocol = ksmbd_max_protocol();
 340         server_conf.auth_mechs = KSMBD_AUTH_NTLMSSP;
 341 #ifdef CONFIG_SMB_SERVER_KERBEROS5
 342         server_conf.auth_mechs |= KSMBD_AUTH_KRB5 |
 343                                 KSMBD_AUTH_MSKRB5;
 344 #endif
 345         return 0;
 346 }
 347
 348 static void server_ctrl_handle_init(struct server_ctrl_struct *ctrl)
 349 {
 350         int ret;
 351
 352         ret = ksmbd_conn_transport_init();
 353         if (ret) {
 354                 server_queue_ctrl_reset_work();
 355                 return;
 356         }
 357
 358         WRITE_ONCE(server_conf.state, SERVER_STATE_RUNNING);
 359 }
 360
 361 static void server_ctrl_handle_reset(struct server_ctrl_struct *ctrl)
 362 {
 363         ksmbd_ipc_soft_reset();
 364         ksmbd_conn_transport_destroy();
 365         server_conf_free();
 366         server_conf_init();
 367         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 368 }
 369
 370 static void server_ctrl_handle_work(struct work_struct *work)
 371 {
 372         struct server_ctrl_struct *ctrl;
 373
 374         ctrl = container_of(work, struct server_ctrl_struct, ctrl_work);
 375
 376         mutex_lock(&ctrl_lock);
 377         switch (ctrl->type) {
 378         case SERVER_CTRL_TYPE_INIT:
 379                 server_ctrl_handle_init(ctrl);
 380                 break;
 381         case SERVER_CTRL_TYPE_RESET:
 382                 server_ctrl_handle_reset(ctrl);
 383                 break;
 384         default:
 385                 pr_err("Unknown server work type: %d\n", ctrl->type);
 386         }
 387         mutex_unlock(&ctrl_lock);
 388         kfree(ctrl);
 389         module_put(THIS_MODULE);
 390 }
 391
 392 static int __queue_ctrl_work(int type)
 393 {
 394         struct server_ctrl_struct *ctrl;
 395
 396         ctrl = kmalloc(sizeof(struct server_ctrl_struct), GFP_KERNEL);
 397         if (!ctrl)
 398                 return -ENOMEM;
 399
 400         __module_get(THIS_MODULE);
 401         ctrl->type = type;
 402         INIT_WORK(&ctrl->ctrl_work, server_ctrl_handle_work);
 403         queue_work(system_long_wq, &ctrl->ctrl_work);
 404         return 0;
 405 }
 406
 407 int server_queue_ctrl_init_work(void)
 408 {
 409         return __queue_ctrl_work(SERVER_CTRL_TYPE_INIT);
 410 }
 411
 412 int server_queue_ctrl_reset_work(void)
 413 {
 414         return __queue_ctrl_work(SERVER_CTRL_TYPE_RESET);
 415 }
 416
 417 static ssize_t stats_show(struct class *class, struct class_attribute *attr,
 418                           char *buf)
 419 {
 420         /*
 421          * Inc this each time you change stats output format,
 422          * so user space will know what to do.
 423          */
 424         static int stats_version = 2;
 425         static const char * const state[] = {
 426                 "startup",
 427                 "running",
 428                 "reset",
 429                 "shutdown"
 430         };
 431
 432         ssize_t sz = scnprintf(buf, PAGE_SIZE, "%d %s %d %lu\n", stats_version,
 433                                state[server_conf.state], server_conf.tcp_port,
 434                                server_conf.ipc_last_active / HZ);
 435         return sz;
 436 }
 437
 438 static ssize_t kill_server_store(struct class *class,
 439                                  struct class_attribute *attr, const char *buf,
 440                                  size_t len)
 441 {
 442         if (!sysfs_streq(buf, "hard"))
 443                 return len;
 444
 445         pr_info("kill command received\n");
 446         mutex_lock(&ctrl_lock);
 447         WRITE_ONCE(server_conf.state, SERVER_STATE_RESETTING);
 448         __module_get(THIS_MODULE);
 449         server_ctrl_handle_reset(NULL);
 450         module_put(THIS_MODULE);
 451         mutex_unlock(&ctrl_lock);
 452         return len;
 453 }
 454
 455 static const char * const debug_type_strings[] = {"smb", "auth", "vfs",
 456                                                   "oplock", "ipc", "conn",
 457                                                   "rdma"};
 458
 459 static ssize_t debug_show(struct class *class, struct class_attribute *attr,
 460                           char *buf)
 461 {
 462         ssize_t sz = 0;
 463         int i, pos = 0;
 464
 465         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 466                 if ((ksmbd_debug_types >> i) & 1) {
 467                         pos = scnprintf(buf + sz,
 468                                         PAGE_SIZE - sz,
 469                                         "[%s] ",
 470                                         debug_type_strings[i]);
 471                 } else {
 472                         pos = scnprintf(buf + sz,
 473                                         PAGE_SIZE - sz,
 474                                         "%s ",
 475                                         debug_type_strings[i]);
 476                 }
 477                 sz += pos;
 478         }
 479         sz += scnprintf(buf + sz, PAGE_SIZE - sz, "\n");
 480         return sz;
 481 }
 482
 483 static ssize_t debug_store(struct class *class, struct class_attribute *attr,
 484                            const char *buf, size_t len)
 485 {
 486         int i;
 487
 488         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 489                 if (sysfs_streq(buf, "all")) {
 490                         if (ksmbd_debug_types == KSMBD_DEBUG_ALL)
 491                                 ksmbd_debug_types = 0;
 492                         else
 493                                 ksmbd_debug_types = KSMBD_DEBUG_ALL;
 494                         break;
 495                 }
 496
 497                 if (sysfs_streq(buf, debug_type_strings[i])) {
 498                         if (ksmbd_debug_types & (1 << i))
 499                                 ksmbd_debug_types &= ~(1 << i);
 500                         else
 501                                 ksmbd_debug_types |= (1 << i);
 502                         break;
 503                 }
 504         }
 505
 506         return len;
 507 }
 508
 509 static CLASS_ATTR_RO(stats);
 510 static CLASS_ATTR_WO(kill_server);
 511 static CLASS_ATTR_RW(debug);
 512
 513 static struct attribute *ksmbd_control_class_attrs[] = {
 514         &class_attr_stats.attr,
 515         &class_attr_kill_server.attr,
 516         &class_attr_debug.attr,
 517         NULL,
 518 };
 519 ATTRIBUTE_GROUPS(ksmbd_control_class);
 520
 521 static struct class ksmbd_control_class = {
 522         .name           = "ksmbd-control",
 523         .owner          = THIS_MODULE,
 524         .class_groups   = ksmbd_control_class_groups,
 525 };
 526
 527 static int ksmbd_server_shutdown(void)
 528 {
 529         WRITE_ONCE(server_conf.state, SERVER_STATE_SHUTTING_DOWN);
 530
 531         class_unregister(&ksmbd_control_class);
 532         ksmbd_workqueue_destroy();
 533         ksmbd_ipc_release();
 534         ksmbd_conn_transport_destroy();
 535         ksmbd_crypto_destroy();
 536         ksmbd_free_global_file_table();
 537         destroy_lease_table(NULL);
 538         ksmbd_work_pool_destroy();
 539         ksmbd_exit_file_cache();
 540         server_conf_free();
 541         return 0;
 542 }
 543
 544 static int __init ksmbd_server_init(void)
 545 {
 546         int ret;
 547
 548         ret = class_register(&ksmbd_control_class);
 549         if (ret) {
 550                 pr_err("Unable to register ksmbd-control class\n");
 551                 return ret;
 552         }
 553
 554         ksmbd_server_tcp_callbacks_init();
 555
 556         ret = server_conf_init();
 557         if (ret)
 558                 goto err_unregister;
 559
 560         ret = ksmbd_work_pool_init();
 561         if (ret)
 562                 goto err_unregister;
 563
 564         ret = ksmbd_init_file_cache();
 565         if (ret)
 566                 goto err_destroy_work_pools;
 567
 568         ret = ksmbd_ipc_init();
 569         if (ret)
 570                 goto err_exit_file_cache;
 571
 572         ret = ksmbd_init_global_file_table();
 573         if (ret)
 574                 goto err_ipc_release;
 575
 576         ret = ksmbd_inode_hash_init();
 577         if (ret)
 578                 goto err_destroy_file_table;
 579
 580         ret = ksmbd_crypto_create();
 581         if (ret)
 582                 goto err_release_inode_hash;
 583
 584         ret = ksmbd_workqueue_init();
 585         if (ret)
 586                 goto err_crypto_destroy;
 587
 588         pr_warn_once("The ksmbd server is experimental, use at your own risk.\n");
 589
 590         return 0;
 591
 592 err_crypto_destroy:
 593         ksmbd_crypto_destroy();
 594 err_release_inode_hash:
 595         ksmbd_release_inode_hash();
 596 err_destroy_file_table:
 597         ksmbd_free_global_file_table();
 598 err_ipc_release:
 599         ksmbd_ipc_release();
 600 err_exit_file_cache:
 601         ksmbd_exit_file_cache();
 602 err_destroy_work_pools:
 603         ksmbd_work_pool_destroy();
 604 err_unregister:
 605         class_unregister(&ksmbd_control_class);
 606
 607         return ret;
 608 }
 609
 610 /**
 611  * ksmbd_server_exit() - shutdown forker thread and free memory at module exit
 612  */
 613 static void __exit ksmbd_server_exit(void)
 614 {
 615         ksmbd_server_shutdown();
 616         ksmbd_release_inode_hash();
 617 }
 618
 619 MODULE_AUTHOR("Namjae Jeon <[email protected]>");
 620 MODULE_VERSION(KSMBD_VERSION);
 621 MODULE_DESCRIPTION("Linux kernel CIFS/SMB SERVER");
 622 MODULE_LICENSE("GPL");
 623 MODULE_SOFTDEP("pre: ecb");
 624 MODULE_SOFTDEP("pre: hmac");
 625 MODULE_SOFTDEP("pre: md5");
 626 MODULE_SOFTDEP("pre: nls");
 627 MODULE_SOFTDEP("pre: aes");
 628 MODULE_SOFTDEP("pre: cmac");
 629 MODULE_SOFTDEP("pre: sha256");
 630 MODULE_SOFTDEP("pre: sha512");
 631 MODULE_SOFTDEP("pre: aead2");
 632 MODULE_SOFTDEP("pre: ccm");
 633 MODULE_SOFTDEP("pre: gcm");
 634 MODULE_SOFTDEP("pre: crc32");
 635 module_init(ksmbd_server_init)
 636 module_exit(ksmbd_server_exit)