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         }
 241
 242         ksmbd_conn_write(work);
 243 }
 244
 245 /**
 246  * handle_ksmbd_work() - process pending smb work requests
 247  * @wk: smb work containing request command buffer
 248  *
 249  * called by kworker threads to processing remaining smb work requests
 250  */
 251 static void handle_ksmbd_work(struct work_struct *wk)
 252 {
 253         struct ksmbd_work *work = container_of(wk, struct ksmbd_work, work);
 254         struct ksmbd_conn *conn = work->conn;
 255
 256         atomic64_inc(&conn->stats.request_served);
 257
 258         __handle_ksmbd_work(work, conn);
 259
 260         ksmbd_conn_try_dequeue_request(work);
 261         ksmbd_free_work_struct(work);
 262         /*
 263          * Checking waitqueue to dropping pending requests on
 264          * disconnection. waitqueue_active is safe because it
 265          * uses atomic operation for condition.
 266          */
 267         if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
 268                 wake_up(&conn->r_count_q);
 269 }
 270
 271 /**
 272  * queue_ksmbd_work() - queue a smb request to worker thread queue
 273  *              for proccessing smb command and sending response
 274  * @conn:       connection instance
 275  *
 276  * read remaining data from socket create and submit work.
 277  */
 278 static int queue_ksmbd_work(struct ksmbd_conn *conn)
 279 {
 280         struct ksmbd_work *work;
 281
 282         work = ksmbd_alloc_work_struct();
 283         if (!work) {
 284                 pr_err("allocation for work failed\n");
 285                 return -ENOMEM;
 286         }
 287
 288         work->conn = conn;
 289         work->request_buf = conn->request_buf;
 290         conn->request_buf = NULL;
 291
 292         if (ksmbd_init_smb_server(work)) {
 293                 ksmbd_free_work_struct(work);
 294                 return -EINVAL;
 295         }
 296
 297         ksmbd_conn_enqueue_request(work);
 298         atomic_inc(&conn->r_count);
 299         /* update activity on connection */
 300         conn->last_active = jiffies;
 301         INIT_WORK(&work->work, handle_ksmbd_work);
 302         ksmbd_queue_work(work);
 303         return 0;
 304 }
 305
 306 static int ksmbd_server_process_request(struct ksmbd_conn *conn)
 307 {
 308         return queue_ksmbd_work(conn);
 309 }
 310
 311 static int ksmbd_server_terminate_conn(struct ksmbd_conn *conn)
 312 {
 313         ksmbd_sessions_deregister(conn);
 314         destroy_lease_table(conn);
 315         return 0;
 316 }
 317
 318 static void ksmbd_server_tcp_callbacks_init(void)
 319 {
 320         struct ksmbd_conn_ops ops;
 321
 322         ops.process_fn = ksmbd_server_process_request;
 323         ops.terminate_fn = ksmbd_server_terminate_conn;
 324
 325         ksmbd_conn_init_server_callbacks(&ops);
 326 }
 327
 328 static void server_conf_free(void)
 329 {
 330         int i;
 331
 332         for (i = 0; i < ARRAY_SIZE(server_conf.conf); i++) {
 333                 kfree(server_conf.conf[i]);
 334                 server_conf.conf[i] = NULL;
 335         }
 336 }
 337
 338 static int server_conf_init(void)
 339 {
 340         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 341         server_conf.enforced_signing = 0;
 342         server_conf.min_protocol = ksmbd_min_protocol();
 343         server_conf.max_protocol = ksmbd_max_protocol();
 344         server_conf.auth_mechs = KSMBD_AUTH_NTLMSSP;
 345 #ifdef CONFIG_SMB_SERVER_KERBEROS5
 346         server_conf.auth_mechs |= KSMBD_AUTH_KRB5 |
 347                                 KSMBD_AUTH_MSKRB5;
 348 #endif
 349         return 0;
 350 }
 351
 352 static void server_ctrl_handle_init(struct server_ctrl_struct *ctrl)
 353 {
 354         int ret;
 355
 356         ret = ksmbd_conn_transport_init();
 357         if (ret) {
 358                 server_queue_ctrl_reset_work();
 359                 return;
 360         }
 361
 362         WRITE_ONCE(server_conf.state, SERVER_STATE_RUNNING);
 363 }
 364
 365 static void server_ctrl_handle_reset(struct server_ctrl_struct *ctrl)
 366 {
 367         ksmbd_ipc_soft_reset();
 368         ksmbd_conn_transport_destroy();
 369         server_conf_free();
 370         server_conf_init();
 371         WRITE_ONCE(server_conf.state, SERVER_STATE_STARTING_UP);
 372 }
 373
 374 static void server_ctrl_handle_work(struct work_struct *work)
 375 {
 376         struct server_ctrl_struct *ctrl;
 377
 378         ctrl = container_of(work, struct server_ctrl_struct, ctrl_work);
 379
 380         mutex_lock(&ctrl_lock);
 381         switch (ctrl->type) {
 382         case SERVER_CTRL_TYPE_INIT:
 383                 server_ctrl_handle_init(ctrl);
 384                 break;
 385         case SERVER_CTRL_TYPE_RESET:
 386                 server_ctrl_handle_reset(ctrl);
 387                 break;
 388         default:
 389                 pr_err("Unknown server work type: %d\n", ctrl->type);
 390         }
 391         mutex_unlock(&ctrl_lock);
 392         kfree(ctrl);
 393         module_put(THIS_MODULE);
 394 }
 395
 396 static int __queue_ctrl_work(int type)
 397 {
 398         struct server_ctrl_struct *ctrl;
 399
 400         ctrl = kmalloc(sizeof(struct server_ctrl_struct), GFP_KERNEL);
 401         if (!ctrl)
 402                 return -ENOMEM;
 403
 404         __module_get(THIS_MODULE);
 405         ctrl->type = type;
 406         INIT_WORK(&ctrl->ctrl_work, server_ctrl_handle_work);
 407         queue_work(system_long_wq, &ctrl->ctrl_work);
 408         return 0;
 409 }
 410
 411 int server_queue_ctrl_init_work(void)
 412 {
 413         return __queue_ctrl_work(SERVER_CTRL_TYPE_INIT);
 414 }
 415
 416 int server_queue_ctrl_reset_work(void)
 417 {
 418         return __queue_ctrl_work(SERVER_CTRL_TYPE_RESET);
 419 }
 420
 421 static ssize_t stats_show(struct class *class, struct class_attribute *attr,
 422                           char *buf)
 423 {
 424         /*
 425          * Inc this each time you change stats output format,
 426          * so user space will know what to do.
 427          */
 428         static int stats_version = 2;
 429         static const char * const state[] = {
 430                 "startup",
 431                 "running",
 432                 "reset",
 433                 "shutdown"
 434         };
 435
 436         ssize_t sz = scnprintf(buf, PAGE_SIZE, "%d %s %d %lu\n", stats_version,
 437                                state[server_conf.state], server_conf.tcp_port,
 438                                server_conf.ipc_last_active / HZ);
 439         return sz;
 440 }
 441
 442 static ssize_t kill_server_store(struct class *class,
 443                                  struct class_attribute *attr, const char *buf,
 444                                  size_t len)
 445 {
 446         if (!sysfs_streq(buf, "hard"))
 447                 return len;
 448
 449         pr_info("kill command received\n");
 450         mutex_lock(&ctrl_lock);
 451         WRITE_ONCE(server_conf.state, SERVER_STATE_RESETTING);
 452         __module_get(THIS_MODULE);
 453         server_ctrl_handle_reset(NULL);
 454         module_put(THIS_MODULE);
 455         mutex_unlock(&ctrl_lock);
 456         return len;
 457 }
 458
 459 static const char * const debug_type_strings[] = {"smb", "auth", "vfs",
 460                                                   "oplock", "ipc", "conn",
 461                                                   "rdma"};
 462
 463 static ssize_t debug_show(struct class *class, struct class_attribute *attr,
 464                           char *buf)
 465 {
 466         ssize_t sz = 0;
 467         int i, pos = 0;
 468
 469         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 470                 if ((ksmbd_debug_types >> i) & 1) {
 471                         pos = scnprintf(buf + sz,
 472                                         PAGE_SIZE - sz,
 473                                         "[%s] ",
 474                                         debug_type_strings[i]);
 475                 } else {
 476                         pos = scnprintf(buf + sz,
 477                                         PAGE_SIZE - sz,
 478                                         "%s ",
 479                                         debug_type_strings[i]);
 480                 }
 481                 sz += pos;
 482         }
 483         sz += scnprintf(buf + sz, PAGE_SIZE - sz, "\n");
 484         return sz;
 485 }
 486
 487 static ssize_t debug_store(struct class *class, struct class_attribute *attr,
 488                            const char *buf, size_t len)
 489 {
 490         int i;
 491
 492         for (i = 0; i < ARRAY_SIZE(debug_type_strings); i++) {
 493                 if (sysfs_streq(buf, "all")) {
 494                         if (ksmbd_debug_types == KSMBD_DEBUG_ALL)
 495                                 ksmbd_debug_types = 0;
 496                         else
 497                                 ksmbd_debug_types = KSMBD_DEBUG_ALL;
 498                         break;
 499                 }
 500
 501                 if (sysfs_streq(buf, debug_type_strings[i])) {
 502                         if (ksmbd_debug_types & (1 << i))
 503                                 ksmbd_debug_types &= ~(1 << i);
 504                         else
 505                                 ksmbd_debug_types |= (1 << i);
 506                         break;
 507                 }
 508         }
 509
 510         return len;
 511 }
 512
 513 static CLASS_ATTR_RO(stats);
 514 static CLASS_ATTR_WO(kill_server);
 515 static CLASS_ATTR_RW(debug);
 516
 517 static struct attribute *ksmbd_control_class_attrs[] = {
 518         &class_attr_stats.attr,
 519         &class_attr_kill_server.attr,
 520         &class_attr_debug.attr,
 521         NULL,
 522 };
 523 ATTRIBUTE_GROUPS(ksmbd_control_class);
 524
 525 static struct class ksmbd_control_class = {
 526         .name           = "ksmbd-control",
 527         .owner          = THIS_MODULE,
 528         .class_groups   = ksmbd_control_class_groups,
 529 };
 530
 531 static int ksmbd_server_shutdown(void)
 532 {
 533         WRITE_ONCE(server_conf.state, SERVER_STATE_SHUTTING_DOWN);
 534
 535         class_unregister(&ksmbd_control_class);
 536         ksmbd_workqueue_destroy();
 537         ksmbd_ipc_release();
 538         ksmbd_conn_transport_destroy();
 539         ksmbd_crypto_destroy();
 540         ksmbd_free_global_file_table();
 541         destroy_lease_table(NULL);
 542         ksmbd_work_pool_destroy();
 543         ksmbd_exit_file_cache();
 544         server_conf_free();
 545         return 0;
 546 }
 547
 548 static int __init ksmbd_server_init(void)
 549 {
 550         int ret;
 551
 552         ret = class_register(&ksmbd_control_class);
 553         if (ret) {
 554                 pr_err("Unable to register ksmbd-control class\n");
 555                 return ret;
 556         }
 557
 558         ksmbd_server_tcp_callbacks_init();
 559
 560         ret = server_conf_init();
 561         if (ret)
 562                 goto err_unregister;
 563
 564         ret = ksmbd_work_pool_init();
 565         if (ret)
 566                 goto err_unregister;
 567
 568         ret = ksmbd_init_file_cache();
 569         if (ret)
 570                 goto err_destroy_work_pools;
 571
 572         ret = ksmbd_ipc_init();
 573         if (ret)
 574                 goto err_exit_file_cache;
 575
 576         ret = ksmbd_init_global_file_table();
 577         if (ret)
 578                 goto err_ipc_release;
 579
 580         ret = ksmbd_inode_hash_init();
 581         if (ret)
 582                 goto err_destroy_file_table;
 583
 584         ret = ksmbd_crypto_create();
 585         if (ret)
 586                 goto err_release_inode_hash;
 587
 588         ret = ksmbd_workqueue_init();
 589         if (ret)
 590                 goto err_crypto_destroy;
 591
 592         pr_warn_once("The ksmbd server is experimental\n");
 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         ksmbd_release_inode_hash();
 621 }
 622
 623 MODULE_AUTHOR("Namjae Jeon <[email protected]>");
 624 MODULE_VERSION(KSMBD_VERSION);
 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)