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 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__ 25 26 #include <net/tcp_states.h> 27 #include <linux/nfc.h> 28 #include <linux/export.h> 29 30 #include "nfc.h" 31 32 static void rawsock_write_queue_purge(struct sock *sk) 33 { 34 pr_debug("sk=%p\n", sk); 35 36 spin_lock_bh(&sk->sk_write_queue.lock); 37 __skb_queue_purge(&sk->sk_write_queue); 38 nfc_rawsock(sk)->tx_work_scheduled = false; 39 spin_unlock_bh(&sk->sk_write_queue.lock); 40 } 41 42 static void rawsock_report_error(struct sock *sk, int err) 43 { 44 pr_debug("sk=%p err=%d\n", sk, err); 45 46 sk->sk_shutdown = SHUTDOWN_MASK; 47 sk->sk_err = -err; 48 sk->sk_error_report(sk); 49 50 rawsock_write_queue_purge(sk); 51 } 52 53 static int rawsock_release(struct socket *sock) 54 { 55 struct sock *sk = sock->sk; 56 57 pr_debug("sock=%p\n", sock); 58 59 sock_orphan(sk); 60 sock_put(sk); 61 62 return 0; 63 } 64 65 static int rawsock_connect(struct socket *sock, struct sockaddr *_addr, 66 int len, int flags) 67 { 68 struct sock *sk = sock->sk; 69 struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr; 70 struct nfc_dev *dev; 71 int rc = 0; 72 73 pr_debug("sock=%p sk=%p flags=%d\n", sock, sk, flags); 74 75 if (!addr || len < sizeof(struct sockaddr_nfc) || 76 addr->sa_family != AF_NFC) 77 return -EINVAL; 78 79 pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n", 80 addr->dev_idx, addr->target_idx, addr->nfc_protocol); 81 82 lock_sock(sk); 83 84 if (sock->state == SS_CONNECTED) { 85 rc = -EISCONN; 86 goto error; 87 } 88 89 dev = nfc_get_device(addr->dev_idx); 90 if (!dev) { 91 rc = -ENODEV; 92 goto error; 93 } 94 95 if (addr->target_idx > dev->target_idx - 1 || 96 addr->target_idx < dev->target_idx - dev->n_targets) { 97 rc = -EINVAL; 98 goto error; 99 } 100 101 if (addr->target_idx > dev->target_idx - 1 || 102 addr->target_idx < dev->target_idx - dev->n_targets) { 103 rc = -EINVAL; 104 goto error; 105 } 106 107 rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol); 108 if (rc) 109 goto put_dev; 110 111 nfc_rawsock(sk)->dev = dev; 112 nfc_rawsock(sk)->target_idx = addr->target_idx; 113 sock->state = SS_CONNECTED; 114 sk->sk_state = TCP_ESTABLISHED; 115 sk->sk_state_change(sk); 116 117 release_sock(sk); 118 return 0; 119 120 put_dev: 121 nfc_put_device(dev); 122 error: 123 release_sock(sk); 124 return rc; 125 } 126 127 static int rawsock_add_header(struct sk_buff *skb) 128 { 129 *skb_push(skb, NFC_HEADER_SIZE) = 0; 130 131 return 0; 132 } 133 134 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb, 135 int err) 136 { 137 struct sock *sk = (struct sock *) context; 138 139 BUG_ON(in_irq()); 140 141 pr_debug("sk=%p err=%d\n", sk, err); 142 143 if (err) 144 goto error; 145 146 err = rawsock_add_header(skb); 147 if (err) 148 goto error; 149 150 err = sock_queue_rcv_skb(sk, skb); 151 if (err) 152 goto error; 153 154 spin_lock_bh(&sk->sk_write_queue.lock); 155 if (!skb_queue_empty(&sk->sk_write_queue)) 156 schedule_work(&nfc_rawsock(sk)->tx_work); 157 else 158 nfc_rawsock(sk)->tx_work_scheduled = false; 159 spin_unlock_bh(&sk->sk_write_queue.lock); 160 161 sock_put(sk); 162 return; 163 164 error: 165 rawsock_report_error(sk, err); 166 sock_put(sk); 167 } 168 169 static void rawsock_tx_work(struct work_struct *work) 170 { 171 struct sock *sk = to_rawsock_sk(work); 172 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 173 u32 target_idx = nfc_rawsock(sk)->target_idx; 174 struct sk_buff *skb; 175 int rc; 176 177 pr_debug("sk=%p target_idx=%u\n", sk, target_idx); 178 179 if (sk->sk_shutdown & SEND_SHUTDOWN) { 180 rawsock_write_queue_purge(sk); 181 return; 182 } 183 184 skb = skb_dequeue(&sk->sk_write_queue); 185 186 sock_hold(sk); 187 rc = nfc_data_exchange(dev, target_idx, skb, 188 rawsock_data_exchange_complete, sk); 189 if (rc) { 190 rawsock_report_error(sk, rc); 191 sock_put(sk); 192 } 193 } 194 195 static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock, 196 struct msghdr *msg, size_t len) 197 { 198 struct sock *sk = sock->sk; 199 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 200 struct sk_buff *skb; 201 int rc; 202 203 pr_debug("sock=%p sk=%p len=%zu\n", 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 = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc); 212 if (skb == NULL) 213 return rc; 214 215 rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); 216 if (rc < 0) { 217 kfree_skb(skb); 218 return rc; 219 } 220 221 spin_lock_bh(&sk->sk_write_queue.lock); 222 __skb_queue_tail(&sk->sk_write_queue, skb); 223 if (!nfc_rawsock(sk)->tx_work_scheduled) { 224 schedule_work(&nfc_rawsock(sk)->tx_work); 225 nfc_rawsock(sk)->tx_work_scheduled = true; 226 } 227 spin_unlock_bh(&sk->sk_write_queue.lock); 228 229 return len; 230 } 231 232 static int rawsock_recvmsg(struct kiocb *iocb, struct socket *sock, 233 struct msghdr *msg, size_t len, int flags) 234 { 235 int noblock = flags & MSG_DONTWAIT; 236 struct sock *sk = sock->sk; 237 struct sk_buff *skb; 238 int copied; 239 int rc; 240 241 pr_debug("sock=%p sk=%p len=%zu flags=%d\n", sock, sk, len, flags); 242 243 skb = skb_recv_datagram(sk, flags, noblock, &rc); 244 if (!skb) 245 return rc; 246 247 msg->msg_namelen = 0; 248 249 copied = skb->len; 250 if (len < copied) { 251 msg->msg_flags |= MSG_TRUNC; 252 copied = len; 253 } 254 255 rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 256 257 skb_free_datagram(sk, skb); 258 259 return rc ? : copied; 260 } 261 262 263 static const struct proto_ops rawsock_ops = { 264 .family = PF_NFC, 265 .owner = THIS_MODULE, 266 .release = rawsock_release, 267 .bind = sock_no_bind, 268 .connect = rawsock_connect, 269 .socketpair = sock_no_socketpair, 270 .accept = sock_no_accept, 271 .getname = sock_no_getname, 272 .poll = datagram_poll, 273 .ioctl = sock_no_ioctl, 274 .listen = sock_no_listen, 275 .shutdown = sock_no_shutdown, 276 .setsockopt = sock_no_setsockopt, 277 .getsockopt = sock_no_getsockopt, 278 .sendmsg = rawsock_sendmsg, 279 .recvmsg = rawsock_recvmsg, 280 .mmap = sock_no_mmap, 281 }; 282 283 static void rawsock_destruct(struct sock *sk) 284 { 285 pr_debug("sk=%p\n", sk); 286 287 if (sk->sk_state == TCP_ESTABLISHED) { 288 nfc_deactivate_target(nfc_rawsock(sk)->dev, 289 nfc_rawsock(sk)->target_idx); 290 nfc_put_device(nfc_rawsock(sk)->dev); 291 } 292 293 skb_queue_purge(&sk->sk_receive_queue); 294 295 if (!sock_flag(sk, SOCK_DEAD)) { 296 pr_err("Freeing alive NFC raw socket %p\n", sk); 297 return; 298 } 299 } 300 301 static int rawsock_create(struct net *net, struct socket *sock, 302 const struct nfc_protocol *nfc_proto) 303 { 304 struct sock *sk; 305 306 pr_debug("sock=%p\n", sock); 307 308 if (sock->type != SOCK_SEQPACKET) 309 return -ESOCKTNOSUPPORT; 310 311 sock->ops = &rawsock_ops; 312 313 sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto); 314 if (!sk) 315 return -ENOMEM; 316 317 sock_init_data(sock, sk); 318 sk->sk_protocol = nfc_proto->id; 319 sk->sk_destruct = rawsock_destruct; 320 sock->state = SS_UNCONNECTED; 321 322 INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work); 323 nfc_rawsock(sk)->tx_work_scheduled = false; 324 325 return 0; 326 } 327 328 static struct proto rawsock_proto = { 329 .name = "NFC_RAW", 330 .owner = THIS_MODULE, 331 .obj_size = sizeof(struct nfc_rawsock), 332 }; 333 334 static const struct nfc_protocol rawsock_nfc_proto = { 335 .id = NFC_SOCKPROTO_RAW, 336 .proto = &rawsock_proto, 337 .owner = THIS_MODULE, 338 .create = rawsock_create 339 }; 340 341 int __init rawsock_init(void) 342 { 343 int rc; 344 345 rc = nfc_proto_register(&rawsock_nfc_proto); 346 347 return rc; 348 } 349 350 void rawsock_exit(void) 351 { 352 nfc_proto_unregister(&rawsock_nfc_proto); 353 } 354