1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2011 Instituto Nokia de Tecnologia 4 * 5 * Authors: 6 * Aloisio Almeida Jr <aloisio.almeida@openbossa.org> 7 * Lauro Ramos Venancio <lauro.venancio@openbossa.org> 8 */ 9 10 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__ 11 12 #include <net/tcp_states.h> 13 #include <linux/nfc.h> 14 #include <linux/export.h> 15 16 #include "nfc.h" 17 18 static struct nfc_sock_list raw_sk_list = { 19 .lock = __RW_LOCK_UNLOCKED(raw_sk_list.lock) 20 }; 21 22 static void nfc_sock_link(struct nfc_sock_list *l, struct sock *sk) 23 { 24 write_lock(&l->lock); 25 sk_add_node(sk, &l->head); 26 write_unlock(&l->lock); 27 } 28 29 static void nfc_sock_unlink(struct nfc_sock_list *l, struct sock *sk) 30 { 31 write_lock(&l->lock); 32 sk_del_node_init(sk); 33 write_unlock(&l->lock); 34 } 35 36 static void rawsock_write_queue_purge(struct sock *sk) 37 { 38 pr_debug("sk=%p\n", sk); 39 40 spin_lock_bh(&sk->sk_write_queue.lock); 41 __skb_queue_purge(&sk->sk_write_queue); 42 nfc_rawsock(sk)->tx_work_scheduled = false; 43 spin_unlock_bh(&sk->sk_write_queue.lock); 44 } 45 46 static void rawsock_report_error(struct sock *sk, int err) 47 { 48 pr_debug("sk=%p err=%d\n", sk, err); 49 50 sk->sk_shutdown = SHUTDOWN_MASK; 51 sk->sk_err = -err; 52 sk_error_report(sk); 53 54 rawsock_write_queue_purge(sk); 55 } 56 57 static int rawsock_release(struct socket *sock) 58 { 59 struct sock *sk = sock->sk; 60 61 pr_debug("sock=%p sk=%p\n", sock, sk); 62 63 if (!sk) 64 return 0; 65 66 if (sock->type == SOCK_RAW) 67 nfc_sock_unlink(&raw_sk_list, sk); 68 69 sock_orphan(sk); 70 sock_put(sk); 71 72 return 0; 73 } 74 75 static int rawsock_connect(struct socket *sock, struct sockaddr *_addr, 76 int len, int flags) 77 { 78 struct sock *sk = sock->sk; 79 struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr; 80 struct nfc_dev *dev; 81 int rc = 0; 82 83 pr_debug("sock=%p sk=%p flags=%d\n", sock, sk, flags); 84 85 if (!addr || len < sizeof(struct sockaddr_nfc) || 86 addr->sa_family != AF_NFC) 87 return -EINVAL; 88 89 pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n", 90 addr->dev_idx, addr->target_idx, addr->nfc_protocol); 91 92 lock_sock(sk); 93 94 if (sock->state == SS_CONNECTED) { 95 rc = -EISCONN; 96 goto error; 97 } 98 99 dev = nfc_get_device(addr->dev_idx); 100 if (!dev) { 101 rc = -ENODEV; 102 goto error; 103 } 104 105 if (addr->target_idx > dev->target_next_idx - 1 || 106 addr->target_idx < dev->target_next_idx - dev->n_targets) { 107 rc = -EINVAL; 108 goto put_dev; 109 } 110 111 rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol); 112 if (rc) 113 goto put_dev; 114 115 nfc_rawsock(sk)->dev = dev; 116 nfc_rawsock(sk)->target_idx = addr->target_idx; 117 sock->state = SS_CONNECTED; 118 sk->sk_state = TCP_ESTABLISHED; 119 sk->sk_state_change(sk); 120 121 release_sock(sk); 122 return 0; 123 124 put_dev: 125 nfc_put_device(dev); 126 error: 127 release_sock(sk); 128 return rc; 129 } 130 131 static int rawsock_add_header(struct sk_buff *skb) 132 { 133 *(u8 *)skb_push(skb, NFC_HEADER_SIZE) = 0; 134 135 return 0; 136 } 137 138 static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb, 139 int err) 140 { 141 struct sock *sk = (struct sock *) context; 142 143 BUG_ON(in_irq()); 144 145 pr_debug("sk=%p err=%d\n", sk, err); 146 147 if (err) 148 goto error; 149 150 err = rawsock_add_header(skb); 151 if (err) 152 goto error_skb; 153 154 err = sock_queue_rcv_skb(sk, skb); 155 if (err) 156 goto error_skb; 157 158 spin_lock_bh(&sk->sk_write_queue.lock); 159 if (!skb_queue_empty(&sk->sk_write_queue)) 160 schedule_work(&nfc_rawsock(sk)->tx_work); 161 else 162 nfc_rawsock(sk)->tx_work_scheduled = false; 163 spin_unlock_bh(&sk->sk_write_queue.lock); 164 165 sock_put(sk); 166 return; 167 168 error_skb: 169 kfree_skb(skb); 170 171 error: 172 rawsock_report_error(sk, err); 173 sock_put(sk); 174 } 175 176 static void rawsock_tx_work(struct work_struct *work) 177 { 178 struct sock *sk = to_rawsock_sk(work); 179 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 180 u32 target_idx = nfc_rawsock(sk)->target_idx; 181 struct sk_buff *skb; 182 int rc; 183 184 pr_debug("sk=%p target_idx=%u\n", sk, target_idx); 185 186 if (sk->sk_shutdown & SEND_SHUTDOWN) { 187 rawsock_write_queue_purge(sk); 188 return; 189 } 190 191 skb = skb_dequeue(&sk->sk_write_queue); 192 193 sock_hold(sk); 194 rc = nfc_data_exchange(dev, target_idx, skb, 195 rawsock_data_exchange_complete, sk); 196 if (rc) { 197 rawsock_report_error(sk, rc); 198 sock_put(sk); 199 } 200 } 201 202 static int rawsock_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) 203 { 204 struct sock *sk = sock->sk; 205 struct nfc_dev *dev = nfc_rawsock(sk)->dev; 206 struct sk_buff *skb; 207 int rc; 208 209 pr_debug("sock=%p sk=%p len=%zu\n", sock, sk, len); 210 211 if (msg->msg_namelen) 212 return -EOPNOTSUPP; 213 214 if (sock->state != SS_CONNECTED) 215 return -ENOTCONN; 216 217 skb = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc); 218 if (skb == NULL) 219 return rc; 220 221 rc = memcpy_from_msg(skb_put(skb, len), msg, len); 222 if (rc < 0) { 223 kfree_skb(skb); 224 return rc; 225 } 226 227 spin_lock_bh(&sk->sk_write_queue.lock); 228 __skb_queue_tail(&sk->sk_write_queue, skb); 229 if (!nfc_rawsock(sk)->tx_work_scheduled) { 230 schedule_work(&nfc_rawsock(sk)->tx_work); 231 nfc_rawsock(sk)->tx_work_scheduled = true; 232 } 233 spin_unlock_bh(&sk->sk_write_queue.lock); 234 235 return len; 236 } 237 238 static int rawsock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 239 int flags) 240 { 241 int noblock = flags & MSG_DONTWAIT; 242 struct sock *sk = sock->sk; 243 struct sk_buff *skb; 244 int copied; 245 int rc; 246 247 pr_debug("sock=%p sk=%p len=%zu flags=%d\n", sock, sk, len, flags); 248 249 skb = skb_recv_datagram(sk, flags, noblock, &rc); 250 if (!skb) 251 return rc; 252 253 copied = skb->len; 254 if (len < copied) { 255 msg->msg_flags |= MSG_TRUNC; 256 copied = len; 257 } 258 259 rc = skb_copy_datagram_msg(skb, 0, msg, copied); 260 261 skb_free_datagram(sk, skb); 262 263 return rc ? : copied; 264 } 265 266 static const struct proto_ops rawsock_ops = { 267 .family = PF_NFC, 268 .owner = THIS_MODULE, 269 .release = rawsock_release, 270 .bind = sock_no_bind, 271 .connect = rawsock_connect, 272 .socketpair = sock_no_socketpair, 273 .accept = sock_no_accept, 274 .getname = sock_no_getname, 275 .poll = datagram_poll, 276 .ioctl = sock_no_ioctl, 277 .listen = sock_no_listen, 278 .shutdown = sock_no_shutdown, 279 .sendmsg = rawsock_sendmsg, 280 .recvmsg = rawsock_recvmsg, 281 .mmap = sock_no_mmap, 282 }; 283 284 static const struct proto_ops rawsock_raw_ops = { 285 .family = PF_NFC, 286 .owner = THIS_MODULE, 287 .release = rawsock_release, 288 .bind = sock_no_bind, 289 .connect = sock_no_connect, 290 .socketpair = sock_no_socketpair, 291 .accept = sock_no_accept, 292 .getname = sock_no_getname, 293 .poll = datagram_poll, 294 .ioctl = sock_no_ioctl, 295 .listen = sock_no_listen, 296 .shutdown = sock_no_shutdown, 297 .sendmsg = sock_no_sendmsg, 298 .recvmsg = rawsock_recvmsg, 299 .mmap = sock_no_mmap, 300 }; 301 302 static void rawsock_destruct(struct sock *sk) 303 { 304 pr_debug("sk=%p\n", sk); 305 306 if (sk->sk_state == TCP_ESTABLISHED) { 307 nfc_deactivate_target(nfc_rawsock(sk)->dev, 308 nfc_rawsock(sk)->target_idx, 309 NFC_TARGET_MODE_IDLE); 310 nfc_put_device(nfc_rawsock(sk)->dev); 311 } 312 313 skb_queue_purge(&sk->sk_receive_queue); 314 315 if (!sock_flag(sk, SOCK_DEAD)) { 316 pr_err("Freeing alive NFC raw socket %p\n", sk); 317 return; 318 } 319 } 320 321 static int rawsock_create(struct net *net, struct socket *sock, 322 const struct nfc_protocol *nfc_proto, int kern) 323 { 324 struct sock *sk; 325 326 pr_debug("sock=%p\n", sock); 327 328 if ((sock->type != SOCK_SEQPACKET) && (sock->type != SOCK_RAW)) 329 return -ESOCKTNOSUPPORT; 330 331 if (sock->type == SOCK_RAW) { 332 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 333 return -EPERM; 334 sock->ops = &rawsock_raw_ops; 335 } else { 336 sock->ops = &rawsock_ops; 337 } 338 339 sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto, kern); 340 if (!sk) 341 return -ENOMEM; 342 343 sock_init_data(sock, sk); 344 sk->sk_protocol = nfc_proto->id; 345 sk->sk_destruct = rawsock_destruct; 346 sock->state = SS_UNCONNECTED; 347 if (sock->type == SOCK_RAW) 348 nfc_sock_link(&raw_sk_list, sk); 349 else { 350 INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work); 351 nfc_rawsock(sk)->tx_work_scheduled = false; 352 } 353 354 return 0; 355 } 356 357 void nfc_send_to_raw_sock(struct nfc_dev *dev, struct sk_buff *skb, 358 u8 payload_type, u8 direction) 359 { 360 struct sk_buff *skb_copy = NULL, *nskb; 361 struct sock *sk; 362 u8 *data; 363 364 read_lock(&raw_sk_list.lock); 365 366 sk_for_each(sk, &raw_sk_list.head) { 367 if (!skb_copy) { 368 skb_copy = __pskb_copy_fclone(skb, NFC_RAW_HEADER_SIZE, 369 GFP_ATOMIC, true); 370 if (!skb_copy) 371 continue; 372 373 data = skb_push(skb_copy, NFC_RAW_HEADER_SIZE); 374 375 data[0] = dev ? dev->idx : 0xFF; 376 data[1] = direction & 0x01; 377 data[1] |= (payload_type << 1); 378 } 379 380 nskb = skb_clone(skb_copy, GFP_ATOMIC); 381 if (!nskb) 382 continue; 383 384 if (sock_queue_rcv_skb(sk, nskb)) 385 kfree_skb(nskb); 386 } 387 388 read_unlock(&raw_sk_list.lock); 389 390 kfree_skb(skb_copy); 391 } 392 EXPORT_SYMBOL(nfc_send_to_raw_sock); 393 394 static struct proto rawsock_proto = { 395 .name = "NFC_RAW", 396 .owner = THIS_MODULE, 397 .obj_size = sizeof(struct nfc_rawsock), 398 }; 399 400 static const struct nfc_protocol rawsock_nfc_proto = { 401 .id = NFC_SOCKPROTO_RAW, 402 .proto = &rawsock_proto, 403 .owner = THIS_MODULE, 404 .create = rawsock_create 405 }; 406 407 int __init rawsock_init(void) 408 { 409 int rc; 410 411 rc = nfc_proto_register(&rawsock_nfc_proto); 412 413 return rc; 414 } 415 416 void rawsock_exit(void) 417 { 418 nfc_proto_unregister(&rawsock_nfc_proto); 419 } 420