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                 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->allocate_rsp_buf(work))
 171                 return;
 172
 173         if (conn->ops->is_transform_hdr &&
 174             conn->ops->is_transform_hdr(work->request_buf)) {
 175                 rc = conn->ops->decrypt_req(work);
 176                 if (rc < 0) {
 177                         conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
 178                         goto send;
 179                 }
 180
 181                 work->encrypted = true;
 182         }
 183
 184         rc = conn->ops->init_rsp_hdr(work);
 185         if (rc) {
 186                 /* either uid or tid is not correct */
 187                 conn->ops->set_rsp_status(work, STATUS_INVALID_HANDLE);
 188                 goto send;
 189         }
 190
 191         do {
 192                 if (conn->ops->check_user_session) {
 193                         rc = conn->ops->check_user_session(work);
 194                         if (rc < 0) {
 195                                 if (rc == -EINVAL)
 196                                         conn->ops->set_rsp_status(work,
 197                                                 STATUS_INVALID_PARAMETER);
 198                                 else
 199                                         conn->ops->set_rsp_status(work,
 200                                                 STATUS_USER_SESSION_DELETED);
 201                                 goto send;
 202                         } else if (rc > 0) {
 203                                 rc = conn->ops->get_ksmbd_tcon(work);
 204                                 if (rc < 0) {
 205                                         if (rc == -EINVAL)
 206                                                 conn->ops->set_rsp_status(work,
 207                                                         STATUS_INVALID_PARAMETER);
 208                                         else
 209                                                 conn->ops->set_rsp_status(work,
 210                                                         STATUS_NETWORK_NAME_DELETED);
 211                                         goto send;
 212                                 }
 213                         }
 214                 }
 215
 216                 rc = __process_request(work, conn, &command);
 217                 if (rc == SERVER_HANDLER_ABORT)
 218                         break;
 219
 220                 /*
 221                  * Call smb2_set_rsp_credits() function to set number of credits
 222                  * granted in hdr of smb2 response.
 223                  */
 224                 if (conn->ops->set_rsp_credits) {
 225                         spin_lock(&conn->credits_lock);
 226                         rc = conn->ops->set_rsp_credits(work);
 227                         spin_unlock(&conn->credits_lock);
 228                         if (rc < 0) {
 229                                 conn->ops->set_rsp_status(work,
 230                                         STATUS_INVALID_PARAMETER);
 231                                 goto send;
 232                         }
 233                 }
 234
 235                 is_chained = is_chained_smb2_message(work);
 236
 237                 if (work->sess &&
 238                     (work->sess->sign || smb3_11_final_sess_setup_resp(work) ||
 239                      conn->ops->is_sign_req(work, command)))
 240                         conn->ops->set_sign_rsp(work);
 241         } while (is_chained == true);
 242
 243 send:
 244         if (work->tcon)
 245                 ksmbd_tree_connect_put(work->tcon);
 246         smb3_preauth_hash_rsp(work);
 247         if (work->sess && work->sess->enc && work->encrypted &&
 248             conn->ops->encrypt_resp) {
 249                 rc = conn->ops->encrypt_resp(work);
 250                 if (rc < 0)
 251                         conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
 252         }
 253
 254         ksmbd_conn_write(work);
 255 }
 256
 257 /**
 258  * handle_ksmbd_work() - process pending smb work requests
 259  * @wk: smb work containing request command buffer
 260  *
 261  * called by kworker threads to processing remaining smb work requests
 262  */
 263 static void handle_ksmbd_work(struct work_struct *wk)
 264 {
 265         struct ksmbd_work *work = container_of(wk, struct ksmbd_work, work);
 266         struct ksmbd_conn *conn = work->conn;
 267
 268         atomic64_inc(&conn->stats.request_served);
 269
 270         __handle_ksmbd_work(work, conn);
 271
 272         ksmbd_conn_try_dequeue_request(work);
 273         ksmbd_free_work_struct(work);
 274         /*
 275          * Checking waitqueue to dropping pending requests on
 276          * disconnection. waitqueue_active is safe because it
 277          * uses atomic operation for condition.
 278          */
 279         if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
 280                 wake_up(&conn->r_count_q);
 281 }
 282
 283 /**
 284  * queue_ksmbd_work() - queue a smb request to worker thread queue
 285  *              for proccessing smb command and sending response
 286  * @conn:       connection instance
 287  *
 288  * read remaining data from socket create and submit work.
 289  */
 290 static int queue_ksmbd_work(struct ksmbd_conn *conn)
 291 {
 292         struct ksmbd_work *work;
 293         int err;
 294
 295         work = ksmbd_alloc_work_struct();
 296         if (!work) {
 297                 pr_err("allocation for work failed\n");
 298                 return -ENOMEM;
 299         }
 300
 301         work->conn = conn;
 302         work->request_buf = conn->request_buf;
 303         conn->request_buf = NULL;
 304
 305         err = ksmbd_init_smb_server(work);
 306         if (err) {
 307                 ksmbd_free_work_struct(work);
 308                 return 0;
 309         }
 310
 311         ksmbd_conn_enqueue_request(work);
 312         atomic_inc(&conn->r_count);
 313         /* update activity on connection */
 314         conn->last_active = jiffies;
 315         INIT_WORK(&work->work, handle_ksmbd_work);
 316         ksmbd_queue_work(work);
 317         return 0;
 318 }
 319
 320 static int ksmbd_server_process_request(struct ksmbd_conn *conn)
 321 {
 322         return queue_ksmbd_work(conn);
 323 }
 324
 325 static int ksmbd_server_terminate_conn(struct ksmbd_conn *conn)
 326 {
 327         ksmbd_sessions_deregister(conn);
 328         destroy_lease_table(conn);
 329         return 0;
 330 }
 331
 332 static void ksmbd_server_tcp_callbacks_init(void)
 333 {
 334         struct ksmbd_conn_ops ops;
 335
 336         ops.process_fn = ksmbd_server_process_request;
 337         ops.terminate_fn = ksmbd_server_terminate_conn;
 338
 339         ksmbd_conn_init_server_callbacks(&ops);
 340 }
 341
 342 static void server_conf_free(void)
 343 {
 344         int i;
 345
 346         for (i = 0; i < ARRAY_SIZE(server_conf.conf); i++) {
 347                 kfree(server_conf.conf[i]);
 348                 server_conf.conf[i] = NULL;
 349         }
 350 }
 351
 352 static int server_conf_init(void)
 353 {
 354         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 355         server_conf.enforced_signing = 0;
 356         server_conf.min_protocol = ksmbd_min_protocol();
 357         server_conf.max_protocol = ksmbd_max_protocol();
 358         server_conf.auth_mechs = KSMBD_AUTH_NTLMSSP;
 359 #ifdef CONFIG_SMB_SERVER_KERBEROS5
 360         server_conf.auth_mechs |= KSMBD_AUTH_KRB5 |
 361                                 KSMBD_AUTH_MSKRB5;
 362 #endif
 363         return 0;
 364 }
 365
 366 static void server_ctrl_handle_init(struct server_ctrl_struct *ctrl)
 367 {
 368         int ret;
 369
 370         ret = ksmbd_conn_transport_init();
 371         if (ret) {
 372                 server_queue_ctrl_reset_work();
 373                 return;
 374         }
 375
 376         WRITE_ONCE(server_conf.state, SERVER_STATE_RUNNING);
 377 }
 378
 379 static void server_ctrl_handle_reset(struct server_ctrl_struct *ctrl)
 380 {
 381         ksmbd_ipc_soft_reset();
 382         ksmbd_conn_transport_destroy();
 383         server_conf_free();
 384         server_conf_init();
 385         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 386 }
 387
 388 static void server_ctrl_handle_work(struct work_struct *work)
 389 {
 390         struct server_ctrl_struct *ctrl;
 391
 392         ctrl = container_of(work, struct server_ctrl_struct, ctrl_work);
 393
 394         mutex_lock(&ctrl_lock);
 395         switch (ctrl->type) {
 396         case SERVER_CTRL_TYPE_INIT:
 397                 server_ctrl_handle_init(ctrl);
 398                 break;
 399         case SERVER_CTRL_TYPE_RESET:
 400                 server_ctrl_handle_reset(ctrl);
 401                 break;
 402         default:
 403                 pr_err("Unknown server work type: %d\n", ctrl->type);
 404         }
 405         mutex_unlock(&ctrl_lock);
 406         kfree(ctrl);
 407         module_put(THIS_MODULE);
 408 }
 409
 410 static int __queue_ctrl_work(int type)
 411 {
 412         struct server_ctrl_struct *ctrl;
 413
 414         ctrl = kmalloc(sizeof(struct server_ctrl_struct), GFP_KERNEL);
 415         if (!ctrl)
 416                 return -ENOMEM;
 417
 418         __module_get(THIS_MODULE);
 419         ctrl->type = type;
 420         INIT_WORK(&ctrl->ctrl_work, server_ctrl_handle_work);
 421         queue_work(system_long_wq, &ctrl->ctrl_work);
 422         return 0;
 423 }
 424
 425 int server_queue_ctrl_init_work(void)
 426 {
 427         return __queue_ctrl_work(SERVER_CTRL_TYPE_INIT);
 428 }
 429
 430 int server_queue_ctrl_reset_work(void)
 431 {
 432         return __queue_ctrl_work(SERVER_CTRL_TYPE_RESET);
 433 }
 434
 435 static ssize_t stats_show(struct class *class, struct class_attribute *attr,
 436                           char *buf)
 437 {
 438         /*
 439          * Inc this each time you change stats output format,
 440          * so user space will know what to do.
 441          */
 442         static int stats_version = 2;
 443         static const char * const state[] = {
 444                 "startup",
 445                 "running",
 446                 "reset",
 447                 "shutdown"
 448         };
 449         return sysfs_emit(buf, "%d %s %d %lu\n", stats_version,
 450                           state[server_conf.state], server_conf.tcp_port,
 451                           server_conf.ipc_last_active / HZ);
 452 }
 453
 454 static ssize_t kill_server_store(struct class *class,
 455                                  struct class_attribute *attr, const char *buf,
 456                                  size_t len)
 457 {
 458         if (!sysfs_streq(buf, "hard"))
 459                 return len;
 460
 461         pr_info("kill command received\n");
 462         mutex_lock(&ctrl_lock);
 463         WRITE_ONCE(server_conf.state, SERVER_STATE_RESETTING);
 464         __module_get(THIS_MODULE);
 465         server_ctrl_handle_reset(NULL);
 466         module_put(THIS_MODULE);
 467         mutex_unlock(&ctrl_lock);
 468         return len;
 469 }
 470
 471 static const char * const debug_type_strings[] = {"smb", "auth", "vfs",
 472                                                   "oplock", "ipc", "conn",
 473                                                   "rdma"};
 474
 475 static ssize_t debug_show(struct class *class, struct class_attribute *attr,
 476                           char *buf)
 477 {
 478         ssize_t sz = 0;
 479         int i, pos = 0;
 480
 481         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 482                 if ((ksmbd_debug_types >> i) & 1) {
 483                         pos = sysfs_emit_at(buf, sz, "[%s] ", debug_type_strings[i]);
 484                 } else {
 485                         pos = sysfs_emit_at(buf, sz, "%s ", debug_type_strings[i]);
 486                 }
 487                 sz += pos;
 488         }
 489         sz += sysfs_emit_at(buf, sz, "\n");
 490         return sz;
 491 }
 492
 493 static ssize_t debug_store(struct class *class, struct class_attribute *attr,
 494                            const char *buf, size_t len)
 495 {
 496         int i;
 497
 498         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 499                 if (sysfs_streq(buf, "all")) {
 500                         if (ksmbd_debug_types == KSMBD_DEBUG_ALL)
 501                                 ksmbd_debug_types = 0;
 502                         else
 503                                 ksmbd_debug_types = KSMBD_DEBUG_ALL;
 504                         break;
 505                 }
 506
 507                 if (sysfs_streq(buf, debug_type_strings[i])) {
 508                         if (ksmbd_debug_types & (1 << i))
 509                                 ksmbd_debug_types &= ~(1 << i);
 510                         else
 511                                 ksmbd_debug_types |= (1 << i);
 512                         break;
 513                 }
 514         }
 515
 516         return len;
 517 }
 518
 519 static CLASS_ATTR_RO(stats);
 520 static CLASS_ATTR_WO(kill_server);
 521 static CLASS_ATTR_RW(debug);
 522
 523 static struct attribute *ksmbd_control_class_attrs[] = {
 524         &class_attr_stats.attr,
 525         &class_attr_kill_server.attr,
 526         &class_attr_debug.attr,
 527         NULL,
 528 };
 529 ATTRIBUTE_GROUPS(ksmbd_control_class);
 530
 531 static struct class ksmbd_control_class = {
 532         .name           = "ksmbd-control",
 533         .owner          = THIS_MODULE,
 534         .class_groups   = ksmbd_control_class_groups,
 535 };
 536
 537 static int ksmbd_server_shutdown(void)
 538 {
 539         WRITE_ONCE(server_conf.state, SERVER_STATE_SHUTTING_DOWN);
 540
 541         class_unregister(&ksmbd_control_class);
 542         ksmbd_workqueue_destroy();
 543         ksmbd_ipc_release();
 544         ksmbd_conn_transport_destroy();
 545         ksmbd_crypto_destroy();
 546         ksmbd_free_global_file_table();
 547         destroy_lease_table(NULL);
 548         ksmbd_work_pool_destroy();
 549         ksmbd_exit_file_cache();
 550         server_conf_free();
 551         return 0;
 552 }
 553
 554 static int __init ksmbd_server_init(void)
 555 {
 556         int ret;
 557
 558         ret = class_register(&ksmbd_control_class);
 559         if (ret) {
 560                 pr_err("Unable to register ksmbd-control class\n");
 561                 return ret;
 562         }
 563
 564         ksmbd_server_tcp_callbacks_init();
 565
 566         ret = server_conf_init();
 567         if (ret)
 568                 goto err_unregister;
 569
 570         ret = ksmbd_work_pool_init();
 571         if (ret)
 572                 goto err_unregister;
 573
 574         ret = ksmbd_init_file_cache();
 575         if (ret)
 576                 goto err_destroy_work_pools;
 577
 578         ret = ksmbd_ipc_init();
 579         if (ret)
 580                 goto err_exit_file_cache;
 581
 582         ret = ksmbd_init_global_file_table();
 583         if (ret)
 584                 goto err_ipc_release;
 585
 586         ret = ksmbd_inode_hash_init();
 587         if (ret)
 588                 goto err_destroy_file_table;
 589
 590         ret = ksmbd_crypto_create();
 591         if (ret)
 592                 goto err_release_inode_hash;
 593
 594         ret = ksmbd_workqueue_init();
 595         if (ret)
 596                 goto err_crypto_destroy;
 597
 598         return 0;
 599
 600 err_crypto_destroy:
 601         ksmbd_crypto_destroy();
 602 err_release_inode_hash:
 603         ksmbd_release_inode_hash();
 604 err_destroy_file_table:
 605         ksmbd_free_global_file_table();
 606 err_ipc_release:
 607         ksmbd_ipc_release();
 608 err_exit_file_cache:
 609         ksmbd_exit_file_cache();
 610 err_destroy_work_pools:
 611         ksmbd_work_pool_destroy();
 612 err_unregister:
 613         class_unregister(&ksmbd_control_class);
 614
 615         return ret;
 616 }
 617
 618 /**
 619  * ksmbd_server_exit() - shutdown forker thread and free memory at module exit
 620  */
 621 static void __exit ksmbd_server_exit(void)
 622 {
 623         ksmbd_server_shutdown();
 624         rcu_barrier();
 625         ksmbd_release_inode_hash();
 626 }
 627
 628 MODULE_AUTHOR("Namjae Jeon <linkinjeon@kernel.org>");
 629 MODULE_VERSION(KSMBD_VERSION);
 630 MODULE_DESCRIPTION("Linux kernel CIFS/SMB SERVER");
 631 MODULE_LICENSE("GPL");
 632 MODULE_SOFTDEP("pre: ecb");
 633 MODULE_SOFTDEP("pre: hmac");
 634 MODULE_SOFTDEP("pre: md5");
 635 MODULE_SOFTDEP("pre: nls");
 636 MODULE_SOFTDEP("pre: aes");
 637 MODULE_SOFTDEP("pre: cmac");
 638 MODULE_SOFTDEP("pre: sha256");
 639 MODULE_SOFTDEP("pre: sha512");
 640 MODULE_SOFTDEP("pre: aead2");
 641 MODULE_SOFTDEP("pre: ccm");
 642 MODULE_SOFTDEP("pre: gcm");
 643 MODULE_SOFTDEP("pre: crc32");
 644 module_init(ksmbd_server_init)
 645 module_exit(ksmbd_server_exit)