1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2016 Namjae Jeon <namjae.jeon@protocolfreedom.org> 4 * Copyright (C) 2018 Samsung Electronics Co., Ltd. 5 */ 6 7 #include <linux/mutex.h> 8 #include <linux/freezer.h> 9 #include <linux/module.h> 10 11 #include "server.h" 12 #include "smb_common.h" 13 #include "mgmt/ksmbd_ida.h" 14 #include "connection.h" 15 #include "transport_tcp.h" 16 #include "transport_rdma.h" 17 18 static DEFINE_MUTEX(init_lock); 19 20 static struct ksmbd_conn_ops default_conn_ops; 21 22 LIST_HEAD(conn_list); 23 DECLARE_RWSEM(conn_list_lock); 24 25 /** 26 * ksmbd_conn_free() - free resources of the connection instance 27 * 28 * @conn: connection instance to be cleaned up 29 * 30 * During the thread termination, the corresponding conn instance 31 * resources(sock/memory) are released and finally the conn object is freed. 32 */ 33 void ksmbd_conn_free(struct ksmbd_conn *conn) 34 { 35 down_write(&conn_list_lock); 36 list_del(&conn->conns_list); 37 up_write(&conn_list_lock); 38 39 xa_destroy(&conn->sessions); 40 kvfree(conn->request_buf); 41 kfree(conn->preauth_info); 42 if (atomic_dec_and_test(&conn->refcnt)) 43 kfree(conn); 44 } 45 46 /** 47 * ksmbd_conn_alloc() - initialize a new connection instance 48 * 49 * Return: ksmbd_conn struct on success, otherwise NULL 50 */ 51 struct ksmbd_conn *ksmbd_conn_alloc(void) 52 { 53 struct ksmbd_conn *conn; 54 55 conn = kzalloc(sizeof(struct ksmbd_conn), KSMBD_DEFAULT_GFP); 56 if (!conn) 57 return NULL; 58 59 conn->need_neg = true; 60 ksmbd_conn_set_new(conn); 61 conn->local_nls = load_nls("utf8"); 62 if (!conn->local_nls) 63 conn->local_nls = load_nls_default(); 64 if (IS_ENABLED(CONFIG_UNICODE)) 65 conn->um = utf8_load(UNICODE_AGE(12, 1, 0)); 66 else 67 conn->um = ERR_PTR(-EOPNOTSUPP); 68 if (IS_ERR(conn->um)) 69 conn->um = NULL; 70 atomic_set(&conn->req_running, 0); 71 atomic_set(&conn->r_count, 0); 72 atomic_set(&conn->refcnt, 1); 73 conn->total_credits = 1; 74 conn->outstanding_credits = 0; 75 76 init_waitqueue_head(&conn->req_running_q); 77 init_waitqueue_head(&conn->r_count_q); 78 INIT_LIST_HEAD(&conn->conns_list); 79 INIT_LIST_HEAD(&conn->requests); 80 INIT_LIST_HEAD(&conn->async_requests); 81 spin_lock_init(&conn->request_lock); 82 spin_lock_init(&conn->credits_lock); 83 ida_init(&conn->async_ida); 84 xa_init(&conn->sessions); 85 86 spin_lock_init(&conn->llist_lock); 87 INIT_LIST_HEAD(&conn->lock_list); 88 89 init_rwsem(&conn->session_lock); 90 91 down_write(&conn_list_lock); 92 list_add(&conn->conns_list, &conn_list); 93 up_write(&conn_list_lock); 94 return conn; 95 } 96 97 bool ksmbd_conn_lookup_dialect(struct ksmbd_conn *c) 98 { 99 struct ksmbd_conn *t; 100 bool ret = false; 101 102 down_read(&conn_list_lock); 103 list_for_each_entry(t, &conn_list, conns_list) { 104 if (memcmp(t->ClientGUID, c->ClientGUID, SMB2_CLIENT_GUID_SIZE)) 105 continue; 106 107 ret = true; 108 break; 109 } 110 up_read(&conn_list_lock); 111 return ret; 112 } 113 114 void ksmbd_conn_enqueue_request(struct ksmbd_work *work) 115 { 116 struct ksmbd_conn *conn = work->conn; 117 struct list_head *requests_queue = NULL; 118 119 if (conn->ops->get_cmd_val(work) != SMB2_CANCEL_HE) 120 requests_queue = &conn->requests; 121 122 atomic_inc(&conn->req_running); 123 if (requests_queue) { 124 spin_lock(&conn->request_lock); 125 list_add_tail(&work->request_entry, requests_queue); 126 spin_unlock(&conn->request_lock); 127 } 128 } 129 130 void ksmbd_conn_try_dequeue_request(struct ksmbd_work *work) 131 { 132 struct ksmbd_conn *conn = work->conn; 133 134 atomic_dec(&conn->req_running); 135 if (waitqueue_active(&conn->req_running_q)) 136 wake_up(&conn->req_running_q); 137 138 if (list_empty(&work->request_entry) && 139 list_empty(&work->async_request_entry)) 140 return; 141 142 spin_lock(&conn->request_lock); 143 list_del_init(&work->request_entry); 144 spin_unlock(&conn->request_lock); 145 if (work->asynchronous) 146 release_async_work(work); 147 148 wake_up_all(&conn->req_running_q); 149 } 150 151 void ksmbd_conn_lock(struct ksmbd_conn *conn) 152 { 153 mutex_lock(&conn->srv_mutex); 154 } 155 156 void ksmbd_conn_unlock(struct ksmbd_conn *conn) 157 { 158 mutex_unlock(&conn->srv_mutex); 159 } 160 161 void ksmbd_all_conn_set_status(u64 sess_id, u32 status) 162 { 163 struct ksmbd_conn *conn; 164 165 down_read(&conn_list_lock); 166 list_for_each_entry(conn, &conn_list, conns_list) { 167 if (conn->binding || xa_load(&conn->sessions, sess_id)) 168 WRITE_ONCE(conn->status, status); 169 } 170 up_read(&conn_list_lock); 171 } 172 173 void ksmbd_conn_wait_idle(struct ksmbd_conn *conn) 174 { 175 wait_event(conn->req_running_q, atomic_read(&conn->req_running) < 2); 176 } 177 178 int ksmbd_conn_wait_idle_sess_id(struct ksmbd_conn *curr_conn, u64 sess_id) 179 { 180 struct ksmbd_conn *conn; 181 int rc, retry_count = 0, max_timeout = 120; 182 int rcount = 1; 183 184 retry_idle: 185 if (retry_count >= max_timeout) 186 return -EIO; 187 188 down_read(&conn_list_lock); 189 list_for_each_entry(conn, &conn_list, conns_list) { 190 if (conn->binding || xa_load(&conn->sessions, sess_id)) { 191 if (conn == curr_conn) 192 rcount = 2; 193 if (atomic_read(&conn->req_running) >= rcount) { 194 rc = wait_event_timeout(conn->req_running_q, 195 atomic_read(&conn->req_running) < rcount, 196 HZ); 197 if (!rc) { 198 up_read(&conn_list_lock); 199 retry_count++; 200 goto retry_idle; 201 } 202 } 203 } 204 } 205 up_read(&conn_list_lock); 206 207 return 0; 208 } 209 210 int ksmbd_conn_write(struct ksmbd_work *work) 211 { 212 struct ksmbd_conn *conn = work->conn; 213 int sent; 214 215 if (!work->response_buf) { 216 pr_err("NULL response header\n"); 217 return -EINVAL; 218 } 219 220 if (work->send_no_response) 221 return 0; 222 223 if (!work->iov_idx) 224 return -EINVAL; 225 226 ksmbd_conn_lock(conn); 227 sent = conn->transport->ops->writev(conn->transport, work->iov, 228 work->iov_cnt, 229 get_rfc1002_len(work->iov[0].iov_base) + 4, 230 work->need_invalidate_rkey, 231 work->remote_key); 232 ksmbd_conn_unlock(conn); 233 234 if (sent < 0) { 235 pr_err("Failed to send message: %d\n", sent); 236 return sent; 237 } 238 239 return 0; 240 } 241 242 int ksmbd_conn_rdma_read(struct ksmbd_conn *conn, 243 void *buf, unsigned int buflen, 244 struct smb2_buffer_desc_v1 *desc, 245 unsigned int desc_len) 246 { 247 int ret = -EINVAL; 248 249 if (conn->transport->ops->rdma_read) 250 ret = conn->transport->ops->rdma_read(conn->transport, 251 buf, buflen, 252 desc, desc_len); 253 return ret; 254 } 255 256 int ksmbd_conn_rdma_write(struct ksmbd_conn *conn, 257 void *buf, unsigned int buflen, 258 struct smb2_buffer_desc_v1 *desc, 259 unsigned int desc_len) 260 { 261 int ret = -EINVAL; 262 263 if (conn->transport->ops->rdma_write) 264 ret = conn->transport->ops->rdma_write(conn->transport, 265 buf, buflen, 266 desc, desc_len); 267 return ret; 268 } 269 270 bool ksmbd_conn_alive(struct ksmbd_conn *conn) 271 { 272 if (!ksmbd_server_running()) 273 return false; 274 275 if (ksmbd_conn_exiting(conn)) 276 return false; 277 278 if (kthread_should_stop()) 279 return false; 280 281 if (atomic_read(&conn->stats.open_files_count) > 0) 282 return true; 283 284 /* 285 * Stop current session if the time that get last request from client 286 * is bigger than deadtime user configured and opening file count is 287 * zero. 288 */ 289 if (server_conf.deadtime > 0 && 290 time_after(jiffies, conn->last_active + server_conf.deadtime)) { 291 ksmbd_debug(CONN, "No response from client in %lu minutes\n", 292 server_conf.deadtime / SMB_ECHO_INTERVAL); 293 return false; 294 } 295 return true; 296 } 297 298 #define SMB1_MIN_SUPPORTED_HEADER_SIZE (sizeof(struct smb_hdr)) 299 #define SMB2_MIN_SUPPORTED_HEADER_SIZE (sizeof(struct smb2_hdr) + 4) 300 301 /** 302 * ksmbd_conn_handler_loop() - session thread to listen on new smb requests 303 * @p: connection instance 304 * 305 * One thread each per connection 306 * 307 * Return: 0 on success 308 */ 309 int ksmbd_conn_handler_loop(void *p) 310 { 311 struct ksmbd_conn *conn = (struct ksmbd_conn *)p; 312 struct ksmbd_transport *t = conn->transport; 313 unsigned int pdu_size, max_allowed_pdu_size, max_req; 314 char hdr_buf[4] = {0,}; 315 int size; 316 317 mutex_init(&conn->srv_mutex); 318 __module_get(THIS_MODULE); 319 320 if (t->ops->prepare && t->ops->prepare(t)) 321 goto out; 322 323 max_req = server_conf.max_inflight_req; 324 conn->last_active = jiffies; 325 set_freezable(); 326 while (ksmbd_conn_alive(conn)) { 327 if (try_to_freeze()) 328 continue; 329 330 kvfree(conn->request_buf); 331 conn->request_buf = NULL; 332 333 recheck: 334 if (atomic_read(&conn->req_running) + 1 > max_req) { 335 wait_event_interruptible(conn->req_running_q, 336 atomic_read(&conn->req_running) < max_req); 337 goto recheck; 338 } 339 340 size = t->ops->read(t, hdr_buf, sizeof(hdr_buf), -1); 341 if (size != sizeof(hdr_buf)) 342 break; 343 344 pdu_size = get_rfc1002_len(hdr_buf); 345 ksmbd_debug(CONN, "RFC1002 header %u bytes\n", pdu_size); 346 347 if (ksmbd_conn_good(conn)) 348 max_allowed_pdu_size = 349 SMB3_MAX_MSGSIZE + conn->vals->max_write_size; 350 else 351 max_allowed_pdu_size = SMB3_MAX_MSGSIZE; 352 353 if (pdu_size > max_allowed_pdu_size) { 354 pr_err_ratelimited("PDU length(%u) exceeded maximum allowed pdu size(%u) on connection(%d)\n", 355 pdu_size, max_allowed_pdu_size, 356 READ_ONCE(conn->status)); 357 break; 358 } 359 360 /* 361 * Check maximum pdu size(0x00FFFFFF). 362 */ 363 if (pdu_size > MAX_STREAM_PROT_LEN) 364 break; 365 366 if (pdu_size < SMB1_MIN_SUPPORTED_HEADER_SIZE) 367 break; 368 369 /* 4 for rfc1002 length field */ 370 /* 1 for implied bcc[0] */ 371 size = pdu_size + 4 + 1; 372 conn->request_buf = kvmalloc(size, KSMBD_DEFAULT_GFP); 373 if (!conn->request_buf) 374 break; 375 376 memcpy(conn->request_buf, hdr_buf, sizeof(hdr_buf)); 377 378 /* 379 * We already read 4 bytes to find out PDU size, now 380 * read in PDU 381 */ 382 size = t->ops->read(t, conn->request_buf + 4, pdu_size, 2); 383 if (size < 0) { 384 pr_err("sock_read failed: %d\n", size); 385 break; 386 } 387 388 if (size != pdu_size) { 389 pr_err("PDU error. Read: %d, Expected: %d\n", 390 size, pdu_size); 391 continue; 392 } 393 394 if (!ksmbd_smb_request(conn)) 395 break; 396 397 if (((struct smb2_hdr *)smb2_get_msg(conn->request_buf))->ProtocolId == 398 SMB2_PROTO_NUMBER) { 399 if (pdu_size < SMB2_MIN_SUPPORTED_HEADER_SIZE) 400 break; 401 } 402 403 if (!default_conn_ops.process_fn) { 404 pr_err("No connection request callback\n"); 405 break; 406 } 407 408 if (default_conn_ops.process_fn(conn)) { 409 pr_err("Cannot handle request\n"); 410 break; 411 } 412 } 413 414 out: 415 ksmbd_conn_set_releasing(conn); 416 /* Wait till all reference dropped to the Server object*/ 417 ksmbd_debug(CONN, "Wait for all pending requests(%d)\n", atomic_read(&conn->r_count)); 418 wait_event(conn->r_count_q, atomic_read(&conn->r_count) == 0); 419 420 if (IS_ENABLED(CONFIG_UNICODE)) 421 utf8_unload(conn->um); 422 unload_nls(conn->local_nls); 423 if (default_conn_ops.terminate_fn) 424 default_conn_ops.terminate_fn(conn); 425 t->ops->disconnect(t); 426 module_put(THIS_MODULE); 427 return 0; 428 } 429 430 void ksmbd_conn_init_server_callbacks(struct ksmbd_conn_ops *ops) 431 { 432 default_conn_ops.process_fn = ops->process_fn; 433 default_conn_ops.terminate_fn = ops->terminate_fn; 434 } 435 436 int ksmbd_conn_transport_init(void) 437 { 438 int ret; 439 440 mutex_lock(&init_lock); 441 ret = ksmbd_tcp_init(); 442 if (ret) { 443 pr_err("Failed to init TCP subsystem: %d\n", ret); 444 goto out; 445 } 446 447 ret = ksmbd_rdma_init(); 448 if (ret) { 449 pr_err("Failed to init RDMA subsystem: %d\n", ret); 450 goto out; 451 } 452 out: 453 mutex_unlock(&init_lock); 454 return ret; 455 } 456 457 static void stop_sessions(void) 458 { 459 struct ksmbd_conn *conn; 460 struct ksmbd_transport *t; 461 462 again: 463 down_read(&conn_list_lock); 464 list_for_each_entry(conn, &conn_list, conns_list) { 465 t = conn->transport; 466 ksmbd_conn_set_exiting(conn); 467 if (t->ops->shutdown) { 468 up_read(&conn_list_lock); 469 t->ops->shutdown(t); 470 down_read(&conn_list_lock); 471 } 472 } 473 up_read(&conn_list_lock); 474 475 if (!list_empty(&conn_list)) { 476 msleep(100); 477 goto again; 478 } 479 } 480 481 void ksmbd_conn_transport_destroy(void) 482 { 483 mutex_lock(&init_lock); 484 ksmbd_tcp_destroy(); 485 ksmbd_rdma_destroy(); 486 stop_sessions(); 487 mutex_unlock(&init_lock); 488 } 489