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 sk=%p\n", sock, sk); 58 59 if (!sk) 60 return 0; 61 62 sock_orphan(sk); 63 sock_put(sk); 64 65 return 0; 66 } 67 68 static int rawsock_connect(struct socket *sock, struct sockaddr *_addr, 69 int len, int flags) 70 { 71 struct sock *sk = sock->sk; 72 struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr; 73 struct nfc_dev *dev; 74 int rc = 0; 75 76 pr_debug("sock=%p sk=%p flags=%d\n", sock, sk, flags); 77 78 if (!addr || len < sizeof(struct sockaddr_nfc) || 79 addr->sa_family != AF_NFC) 80 return -EINVAL; 81 82 pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n", 83 addr->dev_idx, addr->target_idx, addr->nfc_protocol); 84 85 lock_sock(sk); 86 87 if (sock->state == SS_CONNECTED) { 88 rc = -EISCONN; 89 goto error; 90 } 91 92 dev = nfc_get_device(addr->dev_idx); 93 if (!dev) { 94 rc = -ENODEV; 95 goto error; 96 } 97 98 if (addr->target_idx > dev->target_next_idx - 1 || 99 addr->target_idx < dev->target_next_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 *skb_push(skb, NFC_HEADER_SIZE) = 0; 127 128 return 0; 129 } 130 131 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb, 132 int err) 133 { 134 struct sock *sk = (struct sock *) context; 135 136 BUG_ON(in_irq()); 137 138 pr_debug("sk=%p err=%d\n", sk, err); 139 140 if (err) 141 goto error; 142 143 err = rawsock_add_header(skb); 144 if (err) 145 goto error_skb; 146 147 err = sock_queue_rcv_skb(sk, skb); 148 if (err) 149 goto error_skb; 150 151 spin_lock_bh(&sk->sk_write_queue.lock); 152 if (!skb_queue_empty(&sk->sk_write_queue)) 153 schedule_work(&nfc_rawsock(sk)->tx_work); 154 else 155 nfc_rawsock(sk)->tx_work_scheduled = false; 156 spin_unlock_bh(&sk->sk_write_queue.lock); 157 158 sock_put(sk); 159 return; 160 161 error_skb: 162 kfree_skb(skb); 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 copied = skb->len; 248 if (len < copied) { 249 msg->msg_flags |= MSG_TRUNC; 250 copied = len; 251 } 252 253 rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 254 255 skb_free_datagram(sk, skb); 256 257 return rc ? : copied; 258 } 259 260 static const struct proto_ops rawsock_ops = { 261 .family = PF_NFC, 262 .owner = THIS_MODULE, 263 .release = rawsock_release, 264 .bind = sock_no_bind, 265 .connect = rawsock_connect, 266 .socketpair = sock_no_socketpair, 267 .accept = sock_no_accept, 268 .getname = sock_no_getname, 269 .poll = datagram_poll, 270 .ioctl = sock_no_ioctl, 271 .listen = sock_no_listen, 272 .shutdown = sock_no_shutdown, 273 .setsockopt = sock_no_setsockopt, 274 .getsockopt = sock_no_getsockopt, 275 .sendmsg = rawsock_sendmsg, 276 .recvmsg = rawsock_recvmsg, 277 .mmap = sock_no_mmap, 278 }; 279 280 static void rawsock_destruct(struct sock *sk) 281 { 282 pr_debug("sk=%p\n", sk); 283 284 if (sk->sk_state == TCP_ESTABLISHED) { 285 nfc_deactivate_target(nfc_rawsock(sk)->dev, 286 nfc_rawsock(sk)->target_idx); 287 nfc_put_device(nfc_rawsock(sk)->dev); 288 } 289 290 skb_queue_purge(&sk->sk_receive_queue); 291 292 if (!sock_flag(sk, SOCK_DEAD)) { 293 pr_err("Freeing alive NFC raw socket %p\n", sk); 294 return; 295 } 296 } 297 298 static int rawsock_create(struct net *net, struct socket *sock, 299 const struct nfc_protocol *nfc_proto) 300 { 301 struct sock *sk; 302 303 pr_debug("sock=%p\n", sock); 304 305 if (sock->type != SOCK_SEQPACKET) 306 return -ESOCKTNOSUPPORT; 307 308 sock->ops = &rawsock_ops; 309 310 sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto); 311 if (!sk) 312 return -ENOMEM; 313 314 sock_init_data(sock, sk); 315 sk->sk_protocol = nfc_proto->id; 316 sk->sk_destruct = rawsock_destruct; 317 sock->state = SS_UNCONNECTED; 318 319 INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work); 320 nfc_rawsock(sk)->tx_work_scheduled = false; 321 322 return 0; 323 } 324 325 static struct proto rawsock_proto = { 326 .name = "NFC_RAW", 327 .owner = THIS_MODULE, 328 .obj_size = sizeof(struct nfc_rawsock), 329 }; 330 331 static const struct nfc_protocol rawsock_nfc_proto = { 332 .id = NFC_SOCKPROTO_RAW, 333 .proto = &rawsock_proto, 334 .owner = THIS_MODULE, 335 .create = rawsock_create 336 }; 337 338 int __init rawsock_init(void) 339 { 340 int rc; 341 342 rc = nfc_proto_register(&rawsock_nfc_proto); 343 344 return rc; 345 } 346 347 void rawsock_exit(void) 348 { 349 nfc_proto_unregister(&rawsock_nfc_proto); 350 } 351