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