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 void rawsock_write_queue_purge(struct sock *sk) 31 { 32 pr_debug("sk=%p\n", 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 pr_debug("sk=%p err=%d\n", 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 pr_debug("sock=%p sk=%p\n", sock, sk); 56 57 if (!sk) 58 return 0; 59 60 sock_orphan(sk); 61 sock_put(sk); 62 63 return 0; 64 } 65 66 static int rawsock_connect(struct socket *sock, struct sockaddr *_addr, 67 int len, int flags) 68 { 69 struct sock *sk = sock->sk; 70 struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr; 71 struct nfc_dev *dev; 72 int rc = 0; 73 74 pr_debug("sock=%p sk=%p flags=%d\n", sock, sk, flags); 75 76 if (!addr || len < sizeof(struct sockaddr_nfc) || 77 addr->sa_family != AF_NFC) 78 return -EINVAL; 79 80 pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n", 81 addr->dev_idx, addr->target_idx, addr->nfc_protocol); 82 83 lock_sock(sk); 84 85 if (sock->state == SS_CONNECTED) { 86 rc = -EISCONN; 87 goto error; 88 } 89 90 dev = nfc_get_device(addr->dev_idx); 91 if (!dev) { 92 rc = -ENODEV; 93 goto error; 94 } 95 96 if (addr->target_idx > dev->target_next_idx - 1 || 97 addr->target_idx < dev->target_next_idx - dev->n_targets) { 98 rc = -EINVAL; 99 goto error; 100 } 101 102 rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol); 103 if (rc) 104 goto put_dev; 105 106 nfc_rawsock(sk)->dev = dev; 107 nfc_rawsock(sk)->target_idx = addr->target_idx; 108 sock->state = SS_CONNECTED; 109 sk->sk_state = TCP_ESTABLISHED; 110 sk->sk_state_change(sk); 111 112 release_sock(sk); 113 return 0; 114 115 put_dev: 116 nfc_put_device(dev); 117 error: 118 release_sock(sk); 119 return rc; 120 } 121 122 static int rawsock_add_header(struct sk_buff *skb) 123 { 124 *skb_push(skb, NFC_HEADER_SIZE) = 0; 125 126 return 0; 127 } 128 129 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb, 130 int err) 131 { 132 struct sock *sk = (struct sock *) context; 133 134 BUG_ON(in_irq()); 135 136 pr_debug("sk=%p err=%d\n", sk, err); 137 138 if (err) 139 goto error; 140 141 err = rawsock_add_header(skb); 142 if (err) 143 goto error_skb; 144 145 err = sock_queue_rcv_skb(sk, skb); 146 if (err) 147 goto error_skb; 148 149 spin_lock_bh(&sk->sk_write_queue.lock); 150 if (!skb_queue_empty(&sk->sk_write_queue)) 151 schedule_work(&nfc_rawsock(sk)->tx_work); 152 else 153 nfc_rawsock(sk)->tx_work_scheduled = false; 154 spin_unlock_bh(&sk->sk_write_queue.lock); 155 156 sock_put(sk); 157 return; 158 159 error_skb: 160 kfree_skb(skb); 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 pr_debug("sk=%p target_idx=%u\n", 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 pr_debug("sock=%p sk=%p len=%zu\n", 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 = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc); 210 if (skb == NULL) 211 return rc; 212 213 rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); 214 if (rc < 0) { 215 kfree_skb(skb); 216 return rc; 217 } 218 219 spin_lock_bh(&sk->sk_write_queue.lock); 220 __skb_queue_tail(&sk->sk_write_queue, skb); 221 if (!nfc_rawsock(sk)->tx_work_scheduled) { 222 schedule_work(&nfc_rawsock(sk)->tx_work); 223 nfc_rawsock(sk)->tx_work_scheduled = true; 224 } 225 spin_unlock_bh(&sk->sk_write_queue.lock); 226 227 return len; 228 } 229 230 static int rawsock_recvmsg(struct kiocb *iocb, struct socket *sock, 231 struct msghdr *msg, size_t len, int flags) 232 { 233 int noblock = flags & MSG_DONTWAIT; 234 struct sock *sk = sock->sk; 235 struct sk_buff *skb; 236 int copied; 237 int rc; 238 239 pr_debug("sock=%p sk=%p len=%zu flags=%d\n", sock, sk, len, flags); 240 241 skb = skb_recv_datagram(sk, flags, noblock, &rc); 242 if (!skb) 243 return rc; 244 245 copied = skb->len; 246 if (len < copied) { 247 msg->msg_flags |= MSG_TRUNC; 248 copied = len; 249 } 250 251 rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 252 253 skb_free_datagram(sk, skb); 254 255 return rc ? : copied; 256 } 257 258 static const struct proto_ops rawsock_ops = { 259 .family = PF_NFC, 260 .owner = THIS_MODULE, 261 .release = rawsock_release, 262 .bind = sock_no_bind, 263 .connect = rawsock_connect, 264 .socketpair = sock_no_socketpair, 265 .accept = sock_no_accept, 266 .getname = sock_no_getname, 267 .poll = datagram_poll, 268 .ioctl = sock_no_ioctl, 269 .listen = sock_no_listen, 270 .shutdown = sock_no_shutdown, 271 .setsockopt = sock_no_setsockopt, 272 .getsockopt = sock_no_getsockopt, 273 .sendmsg = rawsock_sendmsg, 274 .recvmsg = rawsock_recvmsg, 275 .mmap = sock_no_mmap, 276 }; 277 278 static void rawsock_destruct(struct sock *sk) 279 { 280 pr_debug("sk=%p\n", sk); 281 282 if (sk->sk_state == TCP_ESTABLISHED) { 283 nfc_deactivate_target(nfc_rawsock(sk)->dev, 284 nfc_rawsock(sk)->target_idx); 285 nfc_put_device(nfc_rawsock(sk)->dev); 286 } 287 288 skb_queue_purge(&sk->sk_receive_queue); 289 290 if (!sock_flag(sk, SOCK_DEAD)) { 291 pr_err("Freeing alive NFC raw socket %p\n", sk); 292 return; 293 } 294 } 295 296 static int rawsock_create(struct net *net, struct socket *sock, 297 const struct nfc_protocol *nfc_proto) 298 { 299 struct sock *sk; 300 301 pr_debug("sock=%p\n", sock); 302 303 if (sock->type != SOCK_SEQPACKET) 304 return -ESOCKTNOSUPPORT; 305 306 sock->ops = &rawsock_ops; 307 308 sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto); 309 if (!sk) 310 return -ENOMEM; 311 312 sock_init_data(sock, sk); 313 sk->sk_protocol = nfc_proto->id; 314 sk->sk_destruct = rawsock_destruct; 315 sock->state = SS_UNCONNECTED; 316 317 INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work); 318 nfc_rawsock(sk)->tx_work_scheduled = false; 319 320 return 0; 321 } 322 323 static struct proto rawsock_proto = { 324 .name = "NFC_RAW", 325 .owner = THIS_MODULE, 326 .obj_size = sizeof(struct nfc_rawsock), 327 }; 328 329 static const struct nfc_protocol rawsock_nfc_proto = { 330 .id = NFC_SOCKPROTO_RAW, 331 .proto = &rawsock_proto, 332 .owner = THIS_MODULE, 333 .create = rawsock_create 334 }; 335 336 int __init rawsock_init(void) 337 { 338 int rc; 339 340 rc = nfc_proto_register(&rawsock_nfc_proto); 341 342 return rc; 343 } 344 345 void rawsock_exit(void) 346 { 347 nfc_proto_unregister(&rawsock_nfc_proto); 348 } 349