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 27 #include "nfc.h" 28 29 static void rawsock_write_queue_purge(struct sock *sk) 30 { 31 nfc_dbg("sk=%p", sk); 32 33 spin_lock_bh(&sk->sk_write_queue.lock); 34 __skb_queue_purge(&sk->sk_write_queue); 35 nfc_rawsock(sk)->tx_work_scheduled = false; 36 spin_unlock_bh(&sk->sk_write_queue.lock); 37 } 38 39 static void rawsock_report_error(struct sock *sk, int err) 40 { 41 nfc_dbg("sk=%p err=%d", sk, err); 42 43 sk->sk_shutdown = SHUTDOWN_MASK; 44 sk->sk_err = -err; 45 sk->sk_error_report(sk); 46 47 rawsock_write_queue_purge(sk); 48 } 49 50 static int rawsock_release(struct socket *sock) 51 { 52 struct sock *sk = sock->sk; 53 54 nfc_dbg("sock=%p", sock); 55 56 sock_orphan(sk); 57 sock_put(sk); 58 59 return 0; 60 } 61 62 static int rawsock_connect(struct socket *sock, struct sockaddr *_addr, 63 int len, int flags) 64 { 65 struct sock *sk = sock->sk; 66 struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr; 67 struct nfc_dev *dev; 68 int rc = 0; 69 70 nfc_dbg("sock=%p sk=%p flags=%d", sock, sk, flags); 71 72 if (!addr || len < sizeof(struct sockaddr_nfc) || 73 addr->sa_family != AF_NFC) 74 return -EINVAL; 75 76 nfc_dbg("addr dev_idx=%u target_idx=%u protocol=%u", addr->dev_idx, 77 addr->target_idx, addr->nfc_protocol); 78 79 lock_sock(sk); 80 81 if (sock->state == SS_CONNECTED) { 82 rc = -EISCONN; 83 goto error; 84 } 85 86 dev = nfc_get_device(addr->dev_idx); 87 if (!dev) { 88 rc = -ENODEV; 89 goto error; 90 } 91 92 if (addr->target_idx > dev->target_idx - 1 || 93 addr->target_idx < dev->target_idx - dev->n_targets) { 94 rc = -EINVAL; 95 goto error; 96 } 97 98 if (addr->target_idx > dev->target_idx - 1 || 99 addr->target_idx < dev->target_idx - dev->n_targets) { 100 rc = -EINVAL; 101 goto error; 102 } 103 104 rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol); 105 if (rc) 106 goto put_dev; 107 108 nfc_rawsock(sk)->dev = dev; 109 nfc_rawsock(sk)->target_idx = addr->target_idx; 110 sock->state = SS_CONNECTED; 111 sk->sk_state = TCP_ESTABLISHED; 112 sk->sk_state_change(sk); 113 114 release_sock(sk); 115 return 0; 116 117 put_dev: 118 nfc_put_device(dev); 119 error: 120 release_sock(sk); 121 return rc; 122 } 123 124 static int rawsock_add_header(struct sk_buff *skb) 125 { 126 127 if (skb_cow_head(skb, 1)) 128 return -ENOMEM; 129 130 *skb_push(skb, 1) = 0; 131 132 return 0; 133 } 134 135 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb, 136 int err) 137 { 138 struct sock *sk = (struct sock *) context; 139 140 BUG_ON(in_irq()); 141 142 nfc_dbg("sk=%p err=%d", sk, err); 143 144 if (err) 145 goto error; 146 147 err = rawsock_add_header(skb); 148 if (err) 149 goto error; 150 151 err = sock_queue_rcv_skb(sk, skb); 152 if (err) 153 goto error; 154 155 spin_lock_bh(&sk->sk_write_queue.lock); 156 if (!skb_queue_empty(&sk->sk_write_queue)) 157 schedule_work(&nfc_rawsock(sk)->tx_work); 158 else 159 nfc_rawsock(sk)->tx_work_scheduled = false; 160 spin_unlock_bh(&sk->sk_write_queue.lock); 161 162 sock_put(sk); 163 return; 164 165 error: 166 rawsock_report_error(sk, err); 167 sock_put(sk); 168 } 169 170 static void rawsock_tx_work(struct work_struct *work) 171 { 172 struct sock *sk = to_rawsock_sk(work); 173 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 174 u32 target_idx = nfc_rawsock(sk)->target_idx; 175 struct sk_buff *skb; 176 int rc; 177 178 nfc_dbg("sk=%p target_idx=%u", sk, target_idx); 179 180 if (sk->sk_shutdown & SEND_SHUTDOWN) { 181 rawsock_write_queue_purge(sk); 182 return; 183 } 184 185 skb = skb_dequeue(&sk->sk_write_queue); 186 187 sock_hold(sk); 188 rc = nfc_data_exchange(dev, target_idx, skb, 189 rawsock_data_exchange_complete, sk); 190 if (rc) { 191 rawsock_report_error(sk, rc); 192 sock_put(sk); 193 } 194 } 195 196 static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock, 197 struct msghdr *msg, size_t len) 198 { 199 struct sock *sk = sock->sk; 200 struct sk_buff *skb; 201 int rc; 202 203 nfc_dbg("sock=%p sk=%p len=%zu", sock, sk, len); 204 205 if (msg->msg_namelen) 206 return -EOPNOTSUPP; 207 208 if (sock->state != SS_CONNECTED) 209 return -ENOTCONN; 210 211 skb = sock_alloc_send_skb(sk, len, msg->msg_flags & MSG_DONTWAIT, 212 &rc); 213 if (!skb) 214 return rc; 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