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 ksmbd_conn_lock(conn); 201 sent = conn->transport->ops->writev(conn->transport, work->iov, 202 work->iov_cnt, 203 get_rfc1002_len(work->iov[0].iov_base) + 4, 204 work->need_invalidate_rkey, 205 work->remote_key); 206 ksmbd_conn_unlock(conn); 207 208 if (sent < 0) { 209 pr_err("Failed to send message: %d\n", sent); 210 return sent; 211 } 212 213 return 0; 214 } 215 216 int ksmbd_conn_rdma_read(struct ksmbd_conn *conn, 217 void *buf, unsigned int buflen, 218 struct smb2_buffer_desc_v1 *desc, 219 unsigned int desc_len) 220 { 221 int ret = -EINVAL; 222 223 if (conn->transport->ops->rdma_read) 224 ret = conn->transport->ops->rdma_read(conn->transport, 225 buf, buflen, 226 desc, desc_len); 227 return ret; 228 } 229 230 int ksmbd_conn_rdma_write(struct ksmbd_conn *conn, 231 void *buf, unsigned int buflen, 232 struct smb2_buffer_desc_v1 *desc, 233 unsigned int desc_len) 234 { 235 int ret = -EINVAL; 236 237 if (conn->transport->ops->rdma_write) 238 ret = conn->transport->ops->rdma_write(conn->transport, 239 buf, buflen, 240 desc, desc_len); 241 return ret; 242 } 243 244 bool ksmbd_conn_alive(struct ksmbd_conn *conn) 245 { 246 if (!ksmbd_server_running()) 247 return false; 248 249 if (ksmbd_conn_exiting(conn)) 250 return false; 251 252 if (kthread_should_stop()) 253 return false; 254 255 if (atomic_read(&conn->stats.open_files_count) > 0) 256 return true; 257 258 /* 259 * Stop current session if the time that get last request from client 260 * is bigger than deadtime user configured and opening file count is 261 * zero. 262 */ 263 if (server_conf.deadtime > 0 && 264 time_after(jiffies, conn->last_active + server_conf.deadtime)) { 265 ksmbd_debug(CONN, "No response from client in %lu minutes\n", 266 server_conf.deadtime / SMB_ECHO_INTERVAL); 267 return false; 268 } 269 return true; 270 } 271 272 #define SMB1_MIN_SUPPORTED_HEADER_SIZE (sizeof(struct smb_hdr)) 273 #define SMB2_MIN_SUPPORTED_HEADER_SIZE (sizeof(struct smb2_hdr) + 4) 274 275 /** 276 * ksmbd_conn_handler_loop() - session thread to listen on new smb requests 277 * @p: connection instance 278 * 279 * One thread each per connection 280 * 281 * Return: 0 on success 282 */ 283 int ksmbd_conn_handler_loop(void *p) 284 { 285 struct ksmbd_conn *conn = (struct ksmbd_conn *)p; 286 struct ksmbd_transport *t = conn->transport; 287 unsigned int pdu_size, max_allowed_pdu_size; 288 char hdr_buf[4] = {0,}; 289 int size; 290 291 mutex_init(&conn->srv_mutex); 292 __module_get(THIS_MODULE); 293 294 if (t->ops->prepare && t->ops->prepare(t)) 295 goto out; 296 297 conn->last_active = jiffies; 298 while (ksmbd_conn_alive(conn)) { 299 if (try_to_freeze()) 300 continue; 301 302 kvfree(conn->request_buf); 303 conn->request_buf = NULL; 304 305 size = t->ops->read(t, hdr_buf, sizeof(hdr_buf), -1); 306 if (size != sizeof(hdr_buf)) 307 break; 308 309 pdu_size = get_rfc1002_len(hdr_buf); 310 ksmbd_debug(CONN, "RFC1002 header %u bytes\n", pdu_size); 311 312 if (ksmbd_conn_good(conn)) 313 max_allowed_pdu_size = 314 SMB3_MAX_MSGSIZE + conn->vals->max_write_size; 315 else 316 max_allowed_pdu_size = SMB3_MAX_MSGSIZE; 317 318 if (pdu_size > max_allowed_pdu_size) { 319 pr_err_ratelimited("PDU length(%u) exceeded maximum allowed pdu size(%u) on connection(%d)\n", 320 pdu_size, max_allowed_pdu_size, 321 READ_ONCE(conn->status)); 322 break; 323 } 324 325 /* 326 * Check maximum pdu size(0x00FFFFFF). 327 */ 328 if (pdu_size > MAX_STREAM_PROT_LEN) 329 break; 330 331 if (pdu_size < SMB1_MIN_SUPPORTED_HEADER_SIZE) 332 break; 333 334 /* 4 for rfc1002 length field */ 335 /* 1 for implied bcc[0] */ 336 size = pdu_size + 4 + 1; 337 conn->request_buf = kvmalloc(size, GFP_KERNEL); 338 if (!conn->request_buf) 339 break; 340 341 memcpy(conn->request_buf, hdr_buf, sizeof(hdr_buf)); 342 343 /* 344 * We already read 4 bytes to find out PDU size, now 345 * read in PDU 346 */ 347 size = t->ops->read(t, conn->request_buf + 4, pdu_size, 2); 348 if (size < 0) { 349 pr_err("sock_read failed: %d\n", size); 350 break; 351 } 352 353 if (size != pdu_size) { 354 pr_err("PDU error. Read: %d, Expected: %d\n", 355 size, pdu_size); 356 continue; 357 } 358 359 if (!ksmbd_smb_request(conn)) 360 break; 361 362 if (((struct smb2_hdr *)smb2_get_msg(conn->request_buf))->ProtocolId == 363 SMB2_PROTO_NUMBER) { 364 if (pdu_size < SMB2_MIN_SUPPORTED_HEADER_SIZE) 365 break; 366 } 367 368 if (!default_conn_ops.process_fn) { 369 pr_err("No connection request callback\n"); 370 break; 371 } 372 373 if (default_conn_ops.process_fn(conn)) { 374 pr_err("Cannot handle request\n"); 375 break; 376 } 377 } 378 379 out: 380 ksmbd_conn_set_releasing(conn); 381 /* Wait till all reference dropped to the Server object*/ 382 wait_event(conn->r_count_q, atomic_read(&conn->r_count) == 0); 383 384 if (IS_ENABLED(CONFIG_UNICODE)) 385 utf8_unload(conn->um); 386 unload_nls(conn->local_nls); 387 if (default_conn_ops.terminate_fn) 388 default_conn_ops.terminate_fn(conn); 389 t->ops->disconnect(t); 390 module_put(THIS_MODULE); 391 return 0; 392 } 393 394 void ksmbd_conn_init_server_callbacks(struct ksmbd_conn_ops *ops) 395 { 396 default_conn_ops.process_fn = ops->process_fn; 397 default_conn_ops.terminate_fn = ops->terminate_fn; 398 } 399 400 int ksmbd_conn_transport_init(void) 401 { 402 int ret; 403 404 mutex_lock(&init_lock); 405 ret = ksmbd_tcp_init(); 406 if (ret) { 407 pr_err("Failed to init TCP subsystem: %d\n", ret); 408 goto out; 409 } 410 411 ret = ksmbd_rdma_init(); 412 if (ret) { 413 pr_err("Failed to init RDMA subsystem: %d\n", ret); 414 goto out; 415 } 416 out: 417 mutex_unlock(&init_lock); 418 return ret; 419 } 420 421 static void stop_sessions(void) 422 { 423 struct ksmbd_conn *conn; 424 struct ksmbd_transport *t; 425 426 again: 427 down_read(&conn_list_lock); 428 list_for_each_entry(conn, &conn_list, conns_list) { 429 struct task_struct *task; 430 431 t = conn->transport; 432 task = t->handler; 433 if (task) 434 ksmbd_debug(CONN, "Stop session handler %s/%d\n", 435 task->comm, task_pid_nr(task)); 436 ksmbd_conn_set_exiting(conn); 437 if (t->ops->shutdown) { 438 up_read(&conn_list_lock); 439 t->ops->shutdown(t); 440 down_read(&conn_list_lock); 441 } 442 } 443 up_read(&conn_list_lock); 444 445 if (!list_empty(&conn_list)) { 446 schedule_timeout_interruptible(HZ / 10); /* 100ms */ 447 goto again; 448 } 449 } 450 451 void ksmbd_conn_transport_destroy(void) 452 { 453 mutex_lock(&init_lock); 454 ksmbd_tcp_destroy(); 455 ksmbd_rdma_destroy(); 456 stop_sessions(); 457 mutex_unlock(&init_lock); 458 } 459