1 /* 2 * Copyright (C) 2011 Instituto Nokia de Tecnologia 3 * 4 * Authors: 5 * Aloisio Almeida Jr <aloisio.almeida@openbossa.org> 6 * Lauro Ramos Venancio <lauro.venancio@openbossa.org> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, see <http://www.gnu.org/licenses/>. 20 */ 21 22 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__ 23 24 #include <net/tcp_states.h> 25 #include <linux/nfc.h> 26 #include <linux/export.h> 27 28 #include "nfc.h" 29 30 static struct nfc_sock_list raw_sk_list = { 31 .lock = __RW_LOCK_UNLOCKED(raw_sk_list.lock) 32 }; 33 34 static void nfc_sock_link(struct nfc_sock_list *l, struct sock *sk) 35 { 36 write_lock(&l->lock); 37 sk_add_node(sk, &l->head); 38 write_unlock(&l->lock); 39 } 40 41 static void nfc_sock_unlink(struct nfc_sock_list *l, struct sock *sk) 42 { 43 write_lock(&l->lock); 44 sk_del_node_init(sk); 45 write_unlock(&l->lock); 46 } 47 48 static void rawsock_write_queue_purge(struct sock *sk) 49 { 50 pr_debug("sk=%p\n", sk); 51 52 spin_lock_bh(&sk->sk_write_queue.lock); 53 __skb_queue_purge(&sk->sk_write_queue); 54 nfc_rawsock(sk)->tx_work_scheduled = false; 55 spin_unlock_bh(&sk->sk_write_queue.lock); 56 } 57 58 static void rawsock_report_error(struct sock *sk, int err) 59 { 60 pr_debug("sk=%p err=%d\n", sk, err); 61 62 sk->sk_shutdown = SHUTDOWN_MASK; 63 sk->sk_err = -err; 64 sk->sk_error_report(sk); 65 66 rawsock_write_queue_purge(sk); 67 } 68 69 static int rawsock_release(struct socket *sock) 70 { 71 struct sock *sk = sock->sk; 72 73 pr_debug("sock=%p sk=%p\n", sock, sk); 74 75 if (!sk) 76 return 0; 77 78 if (sock->type == SOCK_RAW) 79 nfc_sock_unlink(&raw_sk_list, sk); 80 81 sock_orphan(sk); 82 sock_put(sk); 83 84 return 0; 85 } 86 87 static int rawsock_connect(struct socket *sock, struct sockaddr *_addr, 88 int len, int flags) 89 { 90 struct sock *sk = sock->sk; 91 struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr; 92 struct nfc_dev *dev; 93 int rc = 0; 94 95 pr_debug("sock=%p sk=%p flags=%d\n", sock, sk, flags); 96 97 if (!addr || len < sizeof(struct sockaddr_nfc) || 98 addr->sa_family != AF_NFC) 99 return -EINVAL; 100 101 pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n", 102 addr->dev_idx, addr->target_idx, addr->nfc_protocol); 103 104 lock_sock(sk); 105 106 if (sock->state == SS_CONNECTED) { 107 rc = -EISCONN; 108 goto error; 109 } 110 111 dev = nfc_get_device(addr->dev_idx); 112 if (!dev) { 113 rc = -ENODEV; 114 goto error; 115 } 116 117 if (addr->target_idx > dev->target_next_idx - 1 || 118 addr->target_idx < dev->target_next_idx - dev->n_targets) { 119 rc = -EINVAL; 120 goto error; 121 } 122 123 rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol); 124 if (rc) 125 goto put_dev; 126 127 nfc_rawsock(sk)->dev = dev; 128 nfc_rawsock(sk)->target_idx = addr->target_idx; 129 sock->state = SS_CONNECTED; 130 sk->sk_state = TCP_ESTABLISHED; 131 sk->sk_state_change(sk); 132 133 release_sock(sk); 134 return 0; 135 136 put_dev: 137 nfc_put_device(dev); 138 error: 139 release_sock(sk); 140 return rc; 141 } 142 143 static int rawsock_add_header(struct sk_buff *skb) 144 { 145 *skb_push(skb, NFC_HEADER_SIZE) = 0; 146 147 return 0; 148 } 149 150 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb, 151 int err) 152 { 153 struct sock *sk = (struct sock *) context; 154 155 BUG_ON(in_irq()); 156 157 pr_debug("sk=%p err=%d\n", sk, err); 158 159 if (err) 160 goto error; 161 162 err = rawsock_add_header(skb); 163 if (err) 164 goto error_skb; 165 166 err = sock_queue_rcv_skb(sk, skb); 167 if (err) 168 goto error_skb; 169 170 spin_lock_bh(&sk->sk_write_queue.lock); 171 if (!skb_queue_empty(&sk->sk_write_queue)) 172 schedule_work(&nfc_rawsock(sk)->tx_work); 173 else 174 nfc_rawsock(sk)->tx_work_scheduled = false; 175 spin_unlock_bh(&sk->sk_write_queue.lock); 176 177 sock_put(sk); 178 return; 179 180 error_skb: 181 kfree_skb(skb); 182 183 error: 184 rawsock_report_error(sk, err); 185 sock_put(sk); 186 } 187 188 static void rawsock_tx_work(struct work_struct *work) 189 { 190 struct sock *sk = to_rawsock_sk(work); 191 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 192 u32 target_idx = nfc_rawsock(sk)->target_idx; 193 struct sk_buff *skb; 194 int rc; 195 196 pr_debug("sk=%p target_idx=%u\n", sk, target_idx); 197 198 if (sk->sk_shutdown & SEND_SHUTDOWN) { 199 rawsock_write_queue_purge(sk); 200 return; 201 } 202 203 skb = skb_dequeue(&sk->sk_write_queue); 204 205 sock_hold(sk); 206 rc = nfc_data_exchange(dev, target_idx, skb, 207 rawsock_data_exchange_complete, sk); 208 if (rc) { 209 rawsock_report_error(sk, rc); 210 sock_put(sk); 211 } 212 } 213 214 static int rawsock_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) 215 { 216 struct sock *sk = sock->sk; 217 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 218 struct sk_buff *skb; 219 int rc; 220 221 pr_debug("sock=%p sk=%p len=%zu\n", sock, sk, len); 222 223 if (msg->msg_namelen) 224 return -EOPNOTSUPP; 225 226 if (sock->state != SS_CONNECTED) 227 return -ENOTCONN; 228 229 skb = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc); 230 if (skb == NULL) 231 return rc; 232 233 rc = memcpy_from_msg(skb_put(skb, len), msg, len); 234 if (rc < 0) { 235 kfree_skb(skb); 236 return rc; 237 } 238 239 spin_lock_bh(&sk->sk_write_queue.lock); 240 __skb_queue_tail(&sk->sk_write_queue, skb); 241 if (!nfc_rawsock(sk)->tx_work_scheduled) { 242 schedule_work(&nfc_rawsock(sk)->tx_work); 243 nfc_rawsock(sk)->tx_work_scheduled = true; 244 } 245 spin_unlock_bh(&sk->sk_write_queue.lock); 246 247 return len; 248 } 249 250 static int rawsock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 251 int flags) 252 { 253 int noblock = flags & MSG_DONTWAIT; 254 struct sock *sk = sock->sk; 255 struct sk_buff *skb; 256 int copied; 257 int rc; 258 259 pr_debug("sock=%p sk=%p len=%zu flags=%d\n", sock, sk, len, flags); 260 261 skb = skb_recv_datagram(sk, flags, noblock, &rc); 262 if (!skb) 263 return rc; 264 265 copied = skb->len; 266 if (len < copied) { 267 msg->msg_flags |= MSG_TRUNC; 268 copied = len; 269 } 270 271 rc = skb_copy_datagram_msg(skb, 0, msg, copied); 272 273 skb_free_datagram(sk, skb); 274 275 return rc ? : copied; 276 } 277 278 static const struct proto_ops rawsock_ops = { 279 .family = PF_NFC, 280 .owner = THIS_MODULE, 281 .release = rawsock_release, 282 .bind = sock_no_bind, 283 .connect = rawsock_connect, 284 .socketpair = sock_no_socketpair, 285 .accept = sock_no_accept, 286 .getname = sock_no_getname, 287 .poll = datagram_poll, 288 .ioctl = sock_no_ioctl, 289 .listen = sock_no_listen, 290 .shutdown = sock_no_shutdown, 291 .setsockopt = sock_no_setsockopt, 292 .getsockopt = sock_no_getsockopt, 293 .sendmsg = rawsock_sendmsg, 294 .recvmsg = rawsock_recvmsg, 295 .mmap = sock_no_mmap, 296 }; 297 298 static const struct proto_ops rawsock_raw_ops = { 299 .family = PF_NFC, 300 .owner = THIS_MODULE, 301 .release = rawsock_release, 302 .bind = sock_no_bind, 303 .connect = sock_no_connect, 304 .socketpair = sock_no_socketpair, 305 .accept = sock_no_accept, 306 .getname = sock_no_getname, 307 .poll = datagram_poll, 308 .ioctl = sock_no_ioctl, 309 .listen = sock_no_listen, 310 .shutdown = sock_no_shutdown, 311 .setsockopt = sock_no_setsockopt, 312 .getsockopt = sock_no_getsockopt, 313 .sendmsg = sock_no_sendmsg, 314 .recvmsg = rawsock_recvmsg, 315 .mmap = sock_no_mmap, 316 }; 317 318 static void rawsock_destruct(struct sock *sk) 319 { 320 pr_debug("sk=%p\n", sk); 321 322 if (sk->sk_state == TCP_ESTABLISHED) { 323 nfc_deactivate_target(nfc_rawsock(sk)->dev, 324 nfc_rawsock(sk)->target_idx, 325 NFC_TARGET_MODE_IDLE); 326 nfc_put_device(nfc_rawsock(sk)->dev); 327 } 328 329 skb_queue_purge(&sk->sk_receive_queue); 330 331 if (!sock_flag(sk, SOCK_DEAD)) { 332 pr_err("Freeing alive NFC raw socket %p\n", sk); 333 return; 334 } 335 } 336 337 static int rawsock_create(struct net *net, struct socket *sock, 338 const struct nfc_protocol *nfc_proto, int kern) 339 { 340 struct sock *sk; 341 342 pr_debug("sock=%p\n", sock); 343 344 if ((sock->type != SOCK_SEQPACKET) && (sock->type != SOCK_RAW)) 345 return -ESOCKTNOSUPPORT; 346 347 if (sock->type == SOCK_RAW) 348 sock->ops = &rawsock_raw_ops; 349 else 350 sock->ops = &rawsock_ops; 351 352 sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto, kern); 353 if (!sk) 354 return -ENOMEM; 355 356 sock_init_data(sock, sk); 357 sk->sk_protocol = nfc_proto->id; 358 sk->sk_destruct = rawsock_destruct; 359 sock->state = SS_UNCONNECTED; 360 if (sock->type == SOCK_RAW) 361 nfc_sock_link(&raw_sk_list, sk); 362 else { 363 INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work); 364 nfc_rawsock(sk)->tx_work_scheduled = false; 365 } 366 367 return 0; 368 } 369 370 void nfc_send_to_raw_sock(struct nfc_dev *dev, struct sk_buff *skb, 371 u8 payload_type, u8 direction) 372 { 373 struct sk_buff *skb_copy = NULL, *nskb; 374 struct sock *sk; 375 u8 *data; 376 377 read_lock(&raw_sk_list.lock); 378 379 sk_for_each(sk, &raw_sk_list.head) { 380 if (!skb_copy) { 381 skb_copy = __pskb_copy_fclone(skb, NFC_RAW_HEADER_SIZE, 382 GFP_ATOMIC, true); 383 if (!skb_copy) 384 continue; 385 386 data = skb_push(skb_copy, NFC_RAW_HEADER_SIZE); 387 388 data[0] = dev ? dev->idx : 0xFF; 389 data[1] = direction & 0x01; 390 data[1] |= (payload_type << 1); 391 } 392 393 nskb = skb_clone(skb_copy, GFP_ATOMIC); 394 if (!nskb) 395 continue; 396 397 if (sock_queue_rcv_skb(sk, nskb)) 398 kfree_skb(nskb); 399 } 400 401 read_unlock(&raw_sk_list.lock); 402 403 kfree_skb(skb_copy); 404 } 405 EXPORT_SYMBOL(nfc_send_to_raw_sock); 406 407 static struct proto rawsock_proto = { 408 .name = "NFC_RAW", 409 .owner = THIS_MODULE, 410 .obj_size = sizeof(struct nfc_rawsock), 411 }; 412 413 static const struct nfc_protocol rawsock_nfc_proto = { 414 .id = NFC_SOCKPROTO_RAW, 415 .proto = &rawsock_proto, 416 .owner = THIS_MODULE, 417 .create = rawsock_create 418 }; 419 420 int __init rawsock_init(void) 421 { 422 int rc; 423 424 rc = nfc_proto_register(&rawsock_nfc_proto); 425 426 return rc; 427 } 428 429 void rawsock_exit(void) 430 { 431 nfc_proto_unregister(&rawsock_nfc_proto); 432 } 433