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