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 rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol); 96 if (rc) 97 goto put_dev; 98 99 nfc_rawsock(sk)->dev = dev; 100 nfc_rawsock(sk)->target_idx = addr->target_idx; 101 sock->state = SS_CONNECTED; 102 sk->sk_state = TCP_ESTABLISHED; 103 sk->sk_state_change(sk); 104 105 release_sock(sk); 106 return 0; 107 108 put_dev: 109 nfc_put_device(dev); 110 error: 111 release_sock(sk); 112 return rc; 113 } 114 115 static int rawsock_add_header(struct sk_buff *skb) 116 { 117 *skb_push(skb, NFC_HEADER_SIZE) = 0; 118 119 return 0; 120 } 121 122 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb, 123 int err) 124 { 125 struct sock *sk = (struct sock *) context; 126 127 BUG_ON(in_irq()); 128 129 pr_debug("sk=%p err=%d\n", sk, err); 130 131 if (err) 132 goto error; 133 134 err = rawsock_add_header(skb); 135 if (err) 136 goto error; 137 138 err = sock_queue_rcv_skb(sk, skb); 139 if (err) 140 goto error; 141 142 spin_lock_bh(&sk->sk_write_queue.lock); 143 if (!skb_queue_empty(&sk->sk_write_queue)) 144 schedule_work(&nfc_rawsock(sk)->tx_work); 145 else 146 nfc_rawsock(sk)->tx_work_scheduled = false; 147 spin_unlock_bh(&sk->sk_write_queue.lock); 148 149 sock_put(sk); 150 return; 151 152 error: 153 rawsock_report_error(sk, err); 154 sock_put(sk); 155 } 156 157 static void rawsock_tx_work(struct work_struct *work) 158 { 159 struct sock *sk = to_rawsock_sk(work); 160 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 161 u32 target_idx = nfc_rawsock(sk)->target_idx; 162 struct sk_buff *skb; 163 int rc; 164 165 pr_debug("sk=%p target_idx=%u\n", sk, target_idx); 166 167 if (sk->sk_shutdown & SEND_SHUTDOWN) { 168 rawsock_write_queue_purge(sk); 169 return; 170 } 171 172 skb = skb_dequeue(&sk->sk_write_queue); 173 174 sock_hold(sk); 175 rc = nfc_data_exchange(dev, target_idx, skb, 176 rawsock_data_exchange_complete, sk); 177 if (rc) { 178 rawsock_report_error(sk, rc); 179 sock_put(sk); 180 } 181 } 182 183 static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock, 184 struct msghdr *msg, size_t len) 185 { 186 struct sock *sk = sock->sk; 187 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 188 struct sk_buff *skb; 189 int rc; 190 191 pr_debug("sock=%p sk=%p len=%zu\n", sock, sk, len); 192 193 if (msg->msg_namelen) 194 return -EOPNOTSUPP; 195 196 if (sock->state != SS_CONNECTED) 197 return -ENOTCONN; 198 199 skb = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc); 200 if (skb == NULL) 201 return rc; 202 203 rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); 204 if (rc < 0) { 205 kfree_skb(skb); 206 return rc; 207 } 208 209 spin_lock_bh(&sk->sk_write_queue.lock); 210 __skb_queue_tail(&sk->sk_write_queue, skb); 211 if (!nfc_rawsock(sk)->tx_work_scheduled) { 212 schedule_work(&nfc_rawsock(sk)->tx_work); 213 nfc_rawsock(sk)->tx_work_scheduled = true; 214 } 215 spin_unlock_bh(&sk->sk_write_queue.lock); 216 217 return len; 218 } 219 220 static int rawsock_recvmsg(struct kiocb *iocb, struct socket *sock, 221 struct msghdr *msg, size_t len, int flags) 222 { 223 int noblock = flags & MSG_DONTWAIT; 224 struct sock *sk = sock->sk; 225 struct sk_buff *skb; 226 int copied; 227 int rc; 228 229 pr_debug("sock=%p sk=%p len=%zu flags=%d\n", sock, sk, len, flags); 230 231 skb = skb_recv_datagram(sk, flags, noblock, &rc); 232 if (!skb) 233 return rc; 234 235 msg->msg_namelen = 0; 236 237 copied = skb->len; 238 if (len < copied) { 239 msg->msg_flags |= MSG_TRUNC; 240 copied = len; 241 } 242 243 rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 244 245 skb_free_datagram(sk, skb); 246 247 return rc ? : copied; 248 } 249 250 251 static const struct proto_ops rawsock_ops = { 252 .family = PF_NFC, 253 .owner = THIS_MODULE, 254 .release = rawsock_release, 255 .bind = sock_no_bind, 256 .connect = rawsock_connect, 257 .socketpair = sock_no_socketpair, 258 .accept = sock_no_accept, 259 .getname = sock_no_getname, 260 .poll = datagram_poll, 261 .ioctl = sock_no_ioctl, 262 .listen = sock_no_listen, 263 .shutdown = sock_no_shutdown, 264 .setsockopt = sock_no_setsockopt, 265 .getsockopt = sock_no_getsockopt, 266 .sendmsg = rawsock_sendmsg, 267 .recvmsg = rawsock_recvmsg, 268 .mmap = sock_no_mmap, 269 }; 270 271 static void rawsock_destruct(struct sock *sk) 272 { 273 pr_debug("sk=%p\n", sk); 274 275 if (sk->sk_state == TCP_ESTABLISHED) { 276 nfc_deactivate_target(nfc_rawsock(sk)->dev, 277 nfc_rawsock(sk)->target_idx); 278 nfc_put_device(nfc_rawsock(sk)->dev); 279 } 280 281 skb_queue_purge(&sk->sk_receive_queue); 282 283 if (!sock_flag(sk, SOCK_DEAD)) { 284 pr_err("Freeing alive NFC raw socket %p\n", sk); 285 return; 286 } 287 } 288 289 static int rawsock_create(struct net *net, struct socket *sock, 290 const struct nfc_protocol *nfc_proto) 291 { 292 struct sock *sk; 293 294 pr_debug("sock=%p\n", sock); 295 296 if (sock->type != SOCK_SEQPACKET) 297 return -ESOCKTNOSUPPORT; 298 299 sock->ops = &rawsock_ops; 300 301 sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto); 302 if (!sk) 303 return -ENOMEM; 304 305 sock_init_data(sock, sk); 306 sk->sk_protocol = nfc_proto->id; 307 sk->sk_destruct = rawsock_destruct; 308 sock->state = SS_UNCONNECTED; 309 310 INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work); 311 nfc_rawsock(sk)->tx_work_scheduled = false; 312 313 return 0; 314 } 315 316 static struct proto rawsock_proto = { 317 .name = "NFC_RAW", 318 .owner = THIS_MODULE, 319 .obj_size = sizeof(struct nfc_rawsock), 320 }; 321 322 static const struct nfc_protocol rawsock_nfc_proto = { 323 .id = NFC_SOCKPROTO_RAW, 324 .proto = &rawsock_proto, 325 .owner = THIS_MODULE, 326 .create = rawsock_create 327 }; 328 329 int __init rawsock_init(void) 330 { 331 int rc; 332 333 rc = nfc_proto_register(&rawsock_nfc_proto); 334 335 return rc; 336 } 337 338 void rawsock_exit(void) 339 { 340 nfc_proto_unregister(&rawsock_nfc_proto); 341 } 342