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, write to the 20 * Free Software Foundation, Inc., 21 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 22 */ 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 void rawsock_write_queue_purge(struct sock *sk) 31 { 32 nfc_dbg("sk=%p", sk); 33 34 spin_lock_bh(&sk->sk_write_queue.lock); 35 __skb_queue_purge(&sk->sk_write_queue); 36 nfc_rawsock(sk)->tx_work_scheduled = false; 37 spin_unlock_bh(&sk->sk_write_queue.lock); 38 } 39 40 static void rawsock_report_error(struct sock *sk, int err) 41 { 42 nfc_dbg("sk=%p err=%d", sk, err); 43 44 sk->sk_shutdown = SHUTDOWN_MASK; 45 sk->sk_err = -err; 46 sk->sk_error_report(sk); 47 48 rawsock_write_queue_purge(sk); 49 } 50 51 static int rawsock_release(struct socket *sock) 52 { 53 struct sock *sk = sock->sk; 54 55 nfc_dbg("sock=%p", sock); 56 57 sock_orphan(sk); 58 sock_put(sk); 59 60 return 0; 61 } 62 63 static int rawsock_connect(struct socket *sock, struct sockaddr *_addr, 64 int len, int flags) 65 { 66 struct sock *sk = sock->sk; 67 struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr; 68 struct nfc_dev *dev; 69 int rc = 0; 70 71 nfc_dbg("sock=%p sk=%p flags=%d", sock, sk, flags); 72 73 if (!addr || len < sizeof(struct sockaddr_nfc) || 74 addr->sa_family != AF_NFC) 75 return -EINVAL; 76 77 nfc_dbg("addr dev_idx=%u target_idx=%u protocol=%u", addr->dev_idx, 78 addr->target_idx, addr->nfc_protocol); 79 80 lock_sock(sk); 81 82 if (sock->state == SS_CONNECTED) { 83 rc = -EISCONN; 84 goto error; 85 } 86 87 dev = nfc_get_device(addr->dev_idx); 88 if (!dev) { 89 rc = -ENODEV; 90 goto error; 91 } 92 93 if (addr->target_idx > dev->target_idx - 1 || 94 addr->target_idx < dev->target_idx - dev->n_targets) { 95 rc = -EINVAL; 96 goto error; 97 } 98 99 if (addr->target_idx > dev->target_idx - 1 || 100 addr->target_idx < dev->target_idx - dev->n_targets) { 101 rc = -EINVAL; 102 goto error; 103 } 104 105 rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol); 106 if (rc) 107 goto put_dev; 108 109 nfc_rawsock(sk)->dev = dev; 110 nfc_rawsock(sk)->target_idx = addr->target_idx; 111 sock->state = SS_CONNECTED; 112 sk->sk_state = TCP_ESTABLISHED; 113 sk->sk_state_change(sk); 114 115 release_sock(sk); 116 return 0; 117 118 put_dev: 119 nfc_put_device(dev); 120 error: 121 release_sock(sk); 122 return rc; 123 } 124 125 static int rawsock_add_header(struct sk_buff *skb) 126 { 127 *skb_push(skb, NFC_HEADER_SIZE) = 0; 128 129 return 0; 130 } 131 132 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb, 133 int err) 134 { 135 struct sock *sk = (struct sock *) context; 136 137 BUG_ON(in_irq()); 138 139 nfc_dbg("sk=%p err=%d", sk, err); 140 141 if (err) 142 goto error; 143 144 err = rawsock_add_header(skb); 145 if (err) 146 goto error; 147 148 err = sock_queue_rcv_skb(sk, skb); 149 if (err) 150 goto error; 151 152 spin_lock_bh(&sk->sk_write_queue.lock); 153 if (!skb_queue_empty(&sk->sk_write_queue)) 154 schedule_work(&nfc_rawsock(sk)->tx_work); 155 else 156 nfc_rawsock(sk)->tx_work_scheduled = false; 157 spin_unlock_bh(&sk->sk_write_queue.lock); 158 159 sock_put(sk); 160 return; 161 162 error: 163 rawsock_report_error(sk, err); 164 sock_put(sk); 165 } 166 167 static void rawsock_tx_work(struct work_struct *work) 168 { 169 struct sock *sk = to_rawsock_sk(work); 170 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 171 u32 target_idx = nfc_rawsock(sk)->target_idx; 172 struct sk_buff *skb; 173 int rc; 174 175 nfc_dbg("sk=%p target_idx=%u", sk, target_idx); 176 177 if (sk->sk_shutdown & SEND_SHUTDOWN) { 178 rawsock_write_queue_purge(sk); 179 return; 180 } 181 182 skb = skb_dequeue(&sk->sk_write_queue); 183 184 sock_hold(sk); 185 rc = nfc_data_exchange(dev, target_idx, skb, 186 rawsock_data_exchange_complete, sk); 187 if (rc) { 188 rawsock_report_error(sk, rc); 189 sock_put(sk); 190 } 191 } 192 193 static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock, 194 struct msghdr *msg, size_t len) 195 { 196 struct sock *sk = sock->sk; 197 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 198 struct sk_buff *skb; 199 int rc; 200 201 nfc_dbg("sock=%p sk=%p len=%zu", sock, sk, len); 202 203 if (msg->msg_namelen) 204 return -EOPNOTSUPP; 205 206 if (sock->state != SS_CONNECTED) 207 return -ENOTCONN; 208 209 skb = sock_alloc_send_skb(sk, len + dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE, 210 msg->msg_flags & MSG_DONTWAIT, &rc); 211 if (!skb) 212 return rc; 213 214 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 215 216 rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); 217 if (rc < 0) { 218 kfree_skb(skb); 219 return rc; 220 } 221 222 spin_lock_bh(&sk->sk_write_queue.lock); 223 __skb_queue_tail(&sk->sk_write_queue, skb); 224 if (!nfc_rawsock(sk)->tx_work_scheduled) { 225 schedule_work(&nfc_rawsock(sk)->tx_work); 226 nfc_rawsock(sk)->tx_work_scheduled = true; 227 } 228 spin_unlock_bh(&sk->sk_write_queue.lock); 229 230 return len; 231 } 232 233 static int rawsock_recvmsg(struct kiocb *iocb, struct socket *sock, 234 struct msghdr *msg, size_t len, int flags) 235 { 236 int noblock = flags & MSG_DONTWAIT; 237 struct sock *sk = sock->sk; 238 struct sk_buff *skb; 239 int copied; 240 int rc; 241 242 nfc_dbg("sock=%p sk=%p len=%zu flags=%d", sock, sk, len, flags); 243 244 skb = skb_recv_datagram(sk, flags, noblock, &rc); 245 if (!skb) 246 return rc; 247 248 msg->msg_namelen = 0; 249 250 copied = skb->len; 251 if (len < copied) { 252 msg->msg_flags |= MSG_TRUNC; 253 copied = len; 254 } 255 256 rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 257 258 skb_free_datagram(sk, skb); 259 260 return rc ? : copied; 261 } 262 263 264 static const struct proto_ops rawsock_ops = { 265 .family = PF_NFC, 266 .owner = THIS_MODULE, 267 .release = rawsock_release, 268 .bind = sock_no_bind, 269 .connect = rawsock_connect, 270 .socketpair = sock_no_socketpair, 271 .accept = sock_no_accept, 272 .getname = sock_no_getname, 273 .poll = datagram_poll, 274 .ioctl = sock_no_ioctl, 275 .listen = sock_no_listen, 276 .shutdown = sock_no_shutdown, 277 .setsockopt = sock_no_setsockopt, 278 .getsockopt = sock_no_getsockopt, 279 .sendmsg = rawsock_sendmsg, 280 .recvmsg = rawsock_recvmsg, 281 .mmap = sock_no_mmap, 282 }; 283 284 static void rawsock_destruct(struct sock *sk) 285 { 286 nfc_dbg("sk=%p", sk); 287 288 if (sk->sk_state == TCP_ESTABLISHED) { 289 nfc_deactivate_target(nfc_rawsock(sk)->dev, 290 nfc_rawsock(sk)->target_idx); 291 nfc_put_device(nfc_rawsock(sk)->dev); 292 } 293 294 skb_queue_purge(&sk->sk_receive_queue); 295 296 if (!sock_flag(sk, SOCK_DEAD)) { 297 nfc_err("Freeing alive NFC raw socket %p", sk); 298 return; 299 } 300 } 301 302 static int rawsock_create(struct net *net, struct socket *sock, 303 const struct nfc_protocol *nfc_proto) 304 { 305 struct sock *sk; 306 307 nfc_dbg("sock=%p", sock); 308 309 if (sock->type != SOCK_SEQPACKET) 310 return -ESOCKTNOSUPPORT; 311 312 sock->ops = &rawsock_ops; 313 314 sk = sk_alloc(net, PF_NFC, GFP_KERNEL, nfc_proto->proto); 315 if (!sk) 316 return -ENOMEM; 317 318 sock_init_data(sock, sk); 319 sk->sk_protocol = nfc_proto->id; 320 sk->sk_destruct = rawsock_destruct; 321 sock->state = SS_UNCONNECTED; 322 323 INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work); 324 nfc_rawsock(sk)->tx_work_scheduled = false; 325 326 return 0; 327 } 328 329 static struct proto rawsock_proto = { 330 .name = "NFC_RAW", 331 .owner = THIS_MODULE, 332 .obj_size = sizeof(struct nfc_rawsock), 333 }; 334 335 static const struct nfc_protocol rawsock_nfc_proto = { 336 .id = NFC_SOCKPROTO_RAW, 337 .proto = &rawsock_proto, 338 .owner = THIS_MODULE, 339 .create = rawsock_create 340 }; 341 342 int __init rawsock_init(void) 343 { 344 int rc; 345 346 rc = nfc_proto_register(&rawsock_nfc_proto); 347 348 return rc; 349 } 350 351 void rawsock_exit(void) 352 { 353 nfc_proto_unregister(&rawsock_nfc_proto); 354 } 355