1/* 2 CMTP implementation for Linux Bluetooth stack (BlueZ). 3 Copyright (C) 2002-2003 Marcel Holtmann <marcel@holtmann.org> 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License version 2 as 7 published by the Free Software Foundation; 8 9 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 10 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 11 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. 12 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY 13 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES 14 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 18 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, 19 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS 20 SOFTWARE IS DISCLAIMED. 21*/ 22 23#include <linux/module.h> 24 25#include <linux/types.h> 26#include <linux/errno.h> 27#include <linux/kernel.h> 28#include <linux/sched.h> 29#include <linux/slab.h> 30#include <linux/poll.h> 31#include <linux/fcntl.h> 32#include <linux/freezer.h> 33#include <linux/skbuff.h> 34#include <linux/socket.h> 35#include <linux/ioctl.h> 36#include <linux/file.h> 37#include <linux/init.h> 38#include <net/sock.h> 39 40#include <linux/isdn/capilli.h> 41 42#include <net/bluetooth/bluetooth.h> 43#include <net/bluetooth/l2cap.h> 44 45#include "cmtp.h" 46 47#define VERSION "1.0" 48 49static DECLARE_RWSEM(cmtp_session_sem); 50static LIST_HEAD(cmtp_session_list); 51 52static struct cmtp_session *__cmtp_get_session(bdaddr_t *bdaddr) 53{ 54 struct cmtp_session *session; 55 struct list_head *p; 56 57 BT_DBG(""); 58 59 list_for_each(p, &cmtp_session_list) { 60 session = list_entry(p, struct cmtp_session, list); 61 if (!bacmp(bdaddr, &session->bdaddr)) 62 return session; 63 } 64 return NULL; 65} 66 67static void __cmtp_link_session(struct cmtp_session *session) 68{ 69 __module_get(THIS_MODULE); 70 list_add(&session->list, &cmtp_session_list); 71} 72 73static void __cmtp_unlink_session(struct cmtp_session *session) 74{ 75 list_del(&session->list); 76 module_put(THIS_MODULE); 77} 78 79static void __cmtp_copy_session(struct cmtp_session *session, struct cmtp_conninfo *ci) 80{ 81 bacpy(&ci->bdaddr, &session->bdaddr); 82 83 ci->flags = session->flags; 84 ci->state = session->state; 85 86 ci->num = session->num; 87} 88 89 90static inline int cmtp_alloc_block_id(struct cmtp_session *session) 91{ 92 int i, id = -1; 93 94 for (i = 0; i < 16; i++) 95 if (!test_and_set_bit(i, &session->blockids)) { 96 id = i; 97 break; 98 } 99 100 return id; 101} 102 103static inline void cmtp_free_block_id(struct cmtp_session *session, int id) 104{ 105 clear_bit(id, &session->blockids); 106} 107 108static inline void cmtp_add_msgpart(struct cmtp_session *session, int id, const unsigned char *buf, int count) 109{ 110 struct sk_buff *skb = session->reassembly[id], *nskb; 111 int size; 112 113 BT_DBG("session %p buf %p count %d", session, buf, count); 114 115 size = (skb) ? skb->len + count : count; 116 117 if (!(nskb = alloc_skb(size, GFP_ATOMIC))) { 118 BT_ERR("Can't allocate memory for CAPI message"); 119 return; 120 } 121 122 if (skb && (skb->len > 0)) 123 skb_copy_from_linear_data(skb, skb_put(nskb, skb->len), skb->len); 124 125 memcpy(skb_put(nskb, count), buf, count); 126 127 session->reassembly[id] = nskb; 128 129 kfree_skb(skb); 130} 131 132static inline int cmtp_recv_frame(struct cmtp_session *session, struct sk_buff *skb) 133{ 134 __u8 hdr, hdrlen, id; 135 __u16 len; 136 137 BT_DBG("session %p skb %p len %d", session, skb, skb->len); 138 139 while (skb->len > 0) { 140 hdr = skb->data[0]; 141 142 switch (hdr & 0xc0) { 143 case 0x40: 144 hdrlen = 2; 145 len = skb->data[1]; 146 break; 147 case 0x80: 148 hdrlen = 3; 149 len = skb->data[1] | (skb->data[2] << 8); 150 break; 151 default: 152 hdrlen = 1; 153 len = 0; 154 break; 155 } 156 157 id = (hdr & 0x3c) >> 2; 158 159 BT_DBG("hdr 0x%02x hdrlen %d len %d id %d", hdr, hdrlen, len, id); 160 161 if (hdrlen + len > skb->len) { 162 BT_ERR("Wrong size or header information in CMTP frame"); 163 break; 164 } 165 166 if (len == 0) { 167 skb_pull(skb, hdrlen); 168 continue; 169 } 170 171 switch (hdr & 0x03) { 172 case 0x00: 173 cmtp_add_msgpart(session, id, skb->data + hdrlen, len); 174 cmtp_recv_capimsg(session, session->reassembly[id]); 175 session->reassembly[id] = NULL; 176 break; 177 case 0x01: 178 cmtp_add_msgpart(session, id, skb->data + hdrlen, len); 179 break; 180 default: 181 if (session->reassembly[id] != NULL) 182 kfree_skb(session->reassembly[id]); 183 session->reassembly[id] = NULL; 184 break; 185 } 186 187 skb_pull(skb, hdrlen + len); 188 } 189 190 kfree_skb(skb); 191 return 0; 192} 193 194static int cmtp_send_frame(struct cmtp_session *session, unsigned char *data, int len) 195{ 196 struct socket *sock = session->sock; 197 struct kvec iv = { data, len }; 198 struct msghdr msg; 199 200 BT_DBG("session %p data %p len %d", session, data, len); 201 202 if (!len) 203 return 0; 204 205 memset(&msg, 0, sizeof(msg)); 206 207 return kernel_sendmsg(sock, &msg, &iv, 1, len); 208} 209 210static void cmtp_process_transmit(struct cmtp_session *session) 211{ 212 struct sk_buff *skb, *nskb; 213 unsigned char *hdr; 214 unsigned int size, tail; 215 216 BT_DBG("session %p", session); 217 218 if (!(nskb = alloc_skb(session->mtu, GFP_ATOMIC))) { 219 BT_ERR("Can't allocate memory for new frame"); 220 return; 221 } 222 223 while ((skb = skb_dequeue(&session->transmit))) { 224 struct cmtp_scb *scb = (void *) skb->cb; 225 226 if ((tail = (session->mtu - nskb->len)) < 5) { 227 cmtp_send_frame(session, nskb->data, nskb->len); 228 skb_trim(nskb, 0); 229 tail = session->mtu; 230 } 231 232 size = min_t(uint, ((tail < 258) ? (tail - 2) : (tail - 3)), skb->len); 233 234 if ((scb->id < 0) && ((scb->id = cmtp_alloc_block_id(session)) < 0)) { 235 skb_queue_head(&session->transmit, skb); 236 break; 237 } 238 239 if (size < 256) { 240 hdr = skb_put(nskb, 2); 241 hdr[0] = 0x40 242 | ((scb->id << 2) & 0x3c) 243 | ((skb->len == size) ? 0x00 : 0x01); 244 hdr[1] = size; 245 } else { 246 hdr = skb_put(nskb, 3); 247 hdr[0] = 0x80 248 | ((scb->id << 2) & 0x3c) 249 | ((skb->len == size) ? 0x00 : 0x01); 250 hdr[1] = size & 0xff; 251 hdr[2] = size >> 8; 252 } 253 254 skb_copy_from_linear_data(skb, skb_put(nskb, size), size); 255 skb_pull(skb, size); 256 257 if (skb->len > 0) { 258 skb_queue_head(&session->transmit, skb); 259 } else { 260 cmtp_free_block_id(session, scb->id); 261 if (scb->data) { 262 cmtp_send_frame(session, nskb->data, nskb->len); 263 skb_trim(nskb, 0); 264 } 265 kfree_skb(skb); 266 } 267 } 268 269 cmtp_send_frame(session, nskb->data, nskb->len); 270 271 kfree_skb(nskb); 272} 273 274static int cmtp_session(void *arg) 275{ 276 struct cmtp_session *session = arg; 277 struct sock *sk = session->sock->sk; 278 struct sk_buff *skb; 279 wait_queue_t wait; 280 281 BT_DBG("session %p", session); 282 283 daemonize("kcmtpd_ctr_%d", session->num); 284 set_user_nice(current, -15); 285 286 init_waitqueue_entry(&wait, current); 287 add_wait_queue(sk_sleep(sk), &wait); 288 while (!atomic_read(&session->terminate)) { 289 set_current_state(TASK_INTERRUPTIBLE); 290 291 if (sk->sk_state != BT_CONNECTED) 292 break; 293 294 while ((skb = skb_dequeue(&sk->sk_receive_queue))) { 295 skb_orphan(skb); 296 cmtp_recv_frame(session, skb); 297 } 298 299 cmtp_process_transmit(session); 300 301 schedule(); 302 } 303 set_current_state(TASK_RUNNING); 304 remove_wait_queue(sk_sleep(sk), &wait); 305 306 down_write(&cmtp_session_sem); 307 308 if (!(session->flags & (1 << CMTP_LOOPBACK))) 309 cmtp_detach_device(session); 310 311 fput(session->sock->file); 312 313 __cmtp_unlink_session(session); 314 315 up_write(&cmtp_session_sem); 316 317 kfree(session); 318 return 0; 319} 320 321int cmtp_add_connection(struct cmtp_connadd_req *req, struct socket *sock) 322{ 323 struct cmtp_session *session, *s; 324 bdaddr_t src, dst; 325 int i, err; 326 327 BT_DBG(""); 328 329 baswap(&src, &bt_sk(sock->sk)->src); 330 baswap(&dst, &bt_sk(sock->sk)->dst); 331 332 session = kzalloc(sizeof(struct cmtp_session), GFP_KERNEL); 333 if (!session) 334 return -ENOMEM; 335 336 down_write(&cmtp_session_sem); 337 338 s = __cmtp_get_session(&bt_sk(sock->sk)->dst); 339 if (s && s->state == BT_CONNECTED) { 340 err = -EEXIST; 341 goto failed; 342 } 343 344 bacpy(&session->bdaddr, &bt_sk(sock->sk)->dst); 345 346 session->mtu = min_t(uint, l2cap_pi(sock->sk)->omtu, l2cap_pi(sock->sk)->imtu); 347 348 BT_DBG("mtu %d", session->mtu); 349 350 sprintf(session->name, "%s", batostr(&dst)); 351 352 session->sock = sock; 353 session->state = BT_CONFIG; 354 355 init_waitqueue_head(&session->wait); 356 357 session->msgnum = CMTP_INITIAL_MSGNUM; 358 359 INIT_LIST_HEAD(&session->applications); 360 361 skb_queue_head_init(&session->transmit); 362 363 for (i = 0; i < 16; i++) 364 session->reassembly[i] = NULL; 365 366 session->flags = req->flags; 367 368 __cmtp_link_session(session); 369 370 err = kernel_thread(cmtp_session, session, CLONE_KERNEL); 371 if (err < 0) 372 goto unlink; 373 374 if (!(session->flags & (1 << CMTP_LOOPBACK))) { 375 err = cmtp_attach_device(session); 376 if (err < 0) 377 goto detach; 378 } 379 380 up_write(&cmtp_session_sem); 381 return 0; 382 383detach: 384 cmtp_detach_device(session); 385 386unlink: 387 __cmtp_unlink_session(session); 388 389failed: 390 up_write(&cmtp_session_sem); 391 kfree(session); 392 return err; 393} 394 395int cmtp_del_connection(struct cmtp_conndel_req *req) 396{ 397 struct cmtp_session *session; 398 int err = 0; 399 400 BT_DBG(""); 401 402 down_read(&cmtp_session_sem); 403 404 session = __cmtp_get_session(&req->bdaddr); 405 if (session) { 406 /* Flush the transmit queue */ 407 skb_queue_purge(&session->transmit); 408 409 /* Kill session thread */ 410 atomic_inc(&session->terminate); 411 cmtp_schedule(session); 412 } else 413 err = -ENOENT; 414 415 up_read(&cmtp_session_sem); 416 return err; 417} 418 419int cmtp_get_connlist(struct cmtp_connlist_req *req) 420{ 421 struct list_head *p; 422 int err = 0, n = 0; 423 424 BT_DBG(""); 425 426 down_read(&cmtp_session_sem); 427 428 list_for_each(p, &cmtp_session_list) { 429 struct cmtp_session *session; 430 struct cmtp_conninfo ci; 431 432 session = list_entry(p, struct cmtp_session, list); 433 434 __cmtp_copy_session(session, &ci); 435 436 if (copy_to_user(req->ci, &ci, sizeof(ci))) { 437 err = -EFAULT; 438 break; 439 } 440 441 if (++n >= req->cnum) 442 break; 443 444 req->ci++; 445 } 446 req->cnum = n; 447 448 up_read(&cmtp_session_sem); 449 return err; 450} 451 452int cmtp_get_conninfo(struct cmtp_conninfo *ci) 453{ 454 struct cmtp_session *session; 455 int err = 0; 456 457 down_read(&cmtp_session_sem); 458 459 session = __cmtp_get_session(&ci->bdaddr); 460 if (session) 461 __cmtp_copy_session(session, ci); 462 else 463 err = -ENOENT; 464 465 up_read(&cmtp_session_sem); 466 return err; 467} 468 469 470static int __init cmtp_init(void) 471{ 472 l2cap_load(); 473 474 BT_INFO("CMTP (CAPI Emulation) ver %s", VERSION); 475 476 cmtp_init_sockets(); 477 478 return 0; 479} 480 481static void __exit cmtp_exit(void) 482{ 483 cmtp_cleanup_sockets(); 484} 485 486module_init(cmtp_init); 487module_exit(cmtp_exit); 488 489MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); 490MODULE_DESCRIPTION("Bluetooth CMTP ver " VERSION); 491MODULE_VERSION(VERSION); 492MODULE_LICENSE("GPL"); 493MODULE_ALIAS("bt-proto-5"); 494