net/ieee802154/dgram.c

   1 /*
   2  * IEEE 802.15.4 dgram socket interface
   3  *
   4  * Copyright 2007, 2008 Siemens AG
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Written by:
  20  * Sergey Lapin <slapin@ossfans.org>
  21  * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
  22  */
  23
  24 #include <linux/net.h>
  25 #include <linux/module.h>
  26 #include <linux/if_arp.h>
  27 #include <linux/list.h>
  28 #include <linux/slab.h>
  29 #include <net/sock.h>
  30 #include <net/af_ieee802154.h>
  31 #include <net/ieee802154.h>
  32 #include <net/ieee802154_netdev.h>
  33
  34 #include <asm/ioctls.h>
  35
  36 #include "af802154.h"
  37
  38 static HLIST_HEAD(dgram_head);
  39 static DEFINE_RWLOCK(dgram_lock);
  40
  41 struct dgram_sock {
  42         struct sock sk;
  43
  44         struct ieee802154_addr src_addr;
  45         struct ieee802154_addr dst_addr;
  46
  47         unsigned int bound:1;
  48         unsigned int want_ack:1;
  49 };
  50
  51 static inline struct dgram_sock *dgram_sk(const struct sock *sk)
  52 {
  53         return container_of(sk, struct dgram_sock, sk);
  54 }
  55
  56 static void dgram_hash(struct sock *sk)
  57 {
  58         write_lock_bh(&dgram_lock);
  59         sk_add_node(sk, &dgram_head);
  60         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  61         write_unlock_bh(&dgram_lock);
  62 }
  63
  64 static void dgram_unhash(struct sock *sk)
  65 {
  66         write_lock_bh(&dgram_lock);
  67         if (sk_del_node_init(sk))
  68                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
  69         write_unlock_bh(&dgram_lock);
  70 }
  71
  72 static int dgram_init(struct sock *sk)
  73 {
  74         struct dgram_sock *ro = dgram_sk(sk);
  75
  76         ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
  77         ro->dst_addr.pan_id = 0xffff;
  78         ro->want_ack = 1;
  79         memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
  80         return 0;
  81 }
  82
  83 static void dgram_close(struct sock *sk, long timeout)
  84 {
  85         sk_common_release(sk);
  86 }
  87
  88 static int dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len)
  89 {
  90         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
  91         struct dgram_sock *ro = dgram_sk(sk);
  92         int err = -EINVAL;
  93         struct net_device *dev;
  94
  95         lock_sock(sk);
  96
  97         ro->bound = 0;
  98
  99         if (len < sizeof(*addr))
 100                 goto out;
 101
 102         if (addr->family != AF_IEEE802154)
 103                 goto out;
 104
 105         dev = ieee802154_get_dev(sock_net(sk), &addr->addr);
 106         if (!dev) {
 107                 err = -ENODEV;
 108                 goto out;
 109         }
 110
 111         if (dev->type != ARPHRD_IEEE802154) {
 112                 err = -ENODEV;
 113                 goto out_put;
 114         }
 115
 116         memcpy(&ro->src_addr, &addr->addr, sizeof(struct ieee802154_addr));
 117
 118         ro->bound = 1;
 119         err = 0;
 120 out_put:
 121         dev_put(dev);
 122 out:
 123         release_sock(sk);
 124
 125         return err;
 126 }
 127
 128 static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
 129 {
 130         switch (cmd) {
 131         case SIOCOUTQ:
 132         {
 133                 int amount = sk_wmem_alloc_get(sk);
 134
 135                 return put_user(amount, (int __user *)arg);
 136         }
 137
 138         case SIOCINQ:
 139         {
 140                 struct sk_buff *skb;
 141                 unsigned long amount;
 142
 143                 amount = 0;
 144                 spin_lock_bh(&sk->sk_receive_queue.lock);
 145                 skb = skb_peek(&sk->sk_receive_queue);
 146                 if (skb != NULL) {
 147                         /*
 148                          * We will only return the amount
 149                          * of this packet since that is all
 150                          * that will be read.
 151                          */
 152                         /* FIXME: parse the header for more correct value */
 153                         amount = skb->len - (3+8+8);
 154                 }
 155                 spin_unlock_bh(&sk->sk_receive_queue.lock);
 156                 return put_user(amount, (int __user *)arg);
 157         }
 158
 159         }
 160         return -ENOIOCTLCMD;
 161 }
 162
 163 /* FIXME: autobind */
 164 static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
 165                         int len)
 166 {
 167         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
 168         struct dgram_sock *ro = dgram_sk(sk);
 169         int err = 0;
 170
 171         if (len < sizeof(*addr))
 172                 return -EINVAL;
 173
 174         if (addr->family != AF_IEEE802154)
 175                 return -EINVAL;
 176
 177         lock_sock(sk);
 178
 179         if (!ro->bound) {
 180                 err = -ENETUNREACH;
 181                 goto out;
 182         }
 183
 184         memcpy(&ro->dst_addr, &addr->addr, sizeof(struct ieee802154_addr));
 185
 186 out:
 187         release_sock(sk);
 188         return err;
 189 }
 190
 191 static int dgram_disconnect(struct sock *sk, int flags)
 192 {
 193         struct dgram_sock *ro = dgram_sk(sk);
 194
 195         lock_sock(sk);
 196
 197         ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
 198         memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
 199
 200         release_sock(sk);
 201
 202         return 0;
 203 }
 204
 205 static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
 206                 struct msghdr *msg, size_t size)
 207 {
 208         struct net_device *dev;
 209         unsigned int mtu;
 210         struct sk_buff *skb;
 211         struct dgram_sock *ro = dgram_sk(sk);
 212         int hlen, tlen;
 213         int err;
 214
 215         if (msg->msg_flags & MSG_OOB) {
 216                 pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
 217                 return -EOPNOTSUPP;
 218         }
 219
 220         if (!ro->bound)
 221                 dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
 222         else
 223                 dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
 224
 225         if (!dev) {
 226                 pr_debug("no dev\n");
 227                 err = -ENXIO;
 228                 goto out;
 229         }
 230         mtu = dev->mtu;
 231         pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 232
 233         if (size > mtu) {
 234                 pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 235                 err = -EINVAL;
 236                 goto out_dev;
 237         }
 238
 239         hlen = LL_RESERVED_SPACE(dev);
 240         tlen = dev->needed_tailroom;
 241         skb = sock_alloc_send_skb(sk, hlen + tlen + size,
 242                         msg->msg_flags & MSG_DONTWAIT,
 243                         &err);
 244         if (!skb)
 245                 goto out_dev;
 246
 247         skb_reserve(skb, hlen);
 248
 249         skb_reset_network_header(skb);
 250
 251         mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
 252         if (ro->want_ack)
 253                 mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;
 254
 255         mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
 256         err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
 257                         ro->bound ? &ro->src_addr : NULL, size);
 258         if (err < 0)
 259                 goto out_skb;
 260
 261         skb_reset_mac_header(skb);
 262
 263         err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 264         if (err < 0)
 265                 goto out_skb;
 266
 267         skb->dev = dev;
 268         skb->sk  = sk;
 269         skb->protocol = htons(ETH_P_IEEE802154);
 270
 271         dev_put(dev);
 272
 273         err = dev_queue_xmit(skb);
 274         if (err > 0)
 275                 err = net_xmit_errno(err);
 276
 277         return err ?: size;
 278
 279 out_skb:
 280         kfree_skb(skb);
 281 out_dev:
 282         dev_put(dev);
 283 out:
 284         return err;
 285 }
 286
 287 static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
 288                 struct msghdr *msg, size_t len, int noblock, int flags,
 289                 int *addr_len)
 290 {
 291         size_t copied = 0;
 292         int err = -EOPNOTSUPP;
 293         struct sk_buff *skb;
 294
 295         skb = skb_recv_datagram(sk, flags, noblock, &err);
 296         if (!skb)
 297                 goto out;
 298
 299         copied = skb->len;
 300         if (len < copied) {
 301                 msg->msg_flags |= MSG_TRUNC;
 302                 copied = len;
 303         }
 304
 305         /* FIXME: skip headers if necessary ?! */
 306         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 307         if (err)
 308                 goto done;
 309
 310         sock_recv_ts_and_drops(msg, sk, skb);
 311
 312         if (flags & MSG_TRUNC)
 313                 copied = skb->len;
 314 done:
 315         skb_free_datagram(sk, skb);
 316 out:
 317         if (err)
 318                 return err;
 319         return copied;
 320 }
 321
 322 static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
 323 {
 324         if (sock_queue_rcv_skb(sk, skb) < 0) {
 325                 kfree_skb(skb);
 326                 return NET_RX_DROP;
 327         }
 328
 329         return NET_RX_SUCCESS;
 330 }
 331
 332 static inline int ieee802154_match_sock(u8 *hw_addr, u16 pan_id,
 333                 u16 short_addr, struct dgram_sock *ro)
 334 {
 335         if (!ro->bound)
 336                 return 1;
 337
 338         if (ro->src_addr.addr_type == IEEE802154_ADDR_LONG &&
 339             !memcmp(ro->src_addr.hwaddr, hw_addr, IEEE802154_ADDR_LEN))
 340                 return 1;
 341
 342         if (ro->src_addr.addr_type == IEEE802154_ADDR_SHORT &&
 343                      pan_id == ro->src_addr.pan_id &&
 344                      short_addr == ro->src_addr.short_addr)
 345                 return 1;
 346
 347         return 0;
 348 }
 349
 350 int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
 351 {
 352         struct sock *sk, *prev = NULL;
 353         struct hlist_node *node;
 354         int ret = NET_RX_SUCCESS;
 355         u16 pan_id, short_addr;
 356
 357         /* Data frame processing */
 358         BUG_ON(dev->type != ARPHRD_IEEE802154);
 359
 360         pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 361         short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
 362
 363         read_lock(&dgram_lock);
 364         sk_for_each(sk, node, &dgram_head) {
 365                 if (ieee802154_match_sock(dev->dev_addr, pan_id, short_addr,
 366                                         dgram_sk(sk))) {
 367                         if (prev) {
 368                                 struct sk_buff *clone;
 369                                 clone = skb_clone(skb, GFP_ATOMIC);
 370                                 if (clone)
 371                                         dgram_rcv_skb(prev, clone);
 372                         }
 373
 374                         prev = sk;
 375                 }
 376         }
 377
 378         if (prev)
 379                 dgram_rcv_skb(prev, skb);
 380         else {
 381                 kfree_skb(skb);
 382                 ret = NET_RX_DROP;
 383         }
 384         read_unlock(&dgram_lock);
 385
 386         return ret;
 387 }
 388
 389 static int dgram_getsockopt(struct sock *sk, int level, int optname,
 390                     char __user *optval, int __user *optlen)
 391 {
 392         struct dgram_sock *ro = dgram_sk(sk);
 393
 394         int val, len;
 395
 396         if (level != SOL_IEEE802154)
 397                 return -EOPNOTSUPP;
 398
 399         if (get_user(len, optlen))
 400                 return -EFAULT;
 401
 402         len = min_t(unsigned int, len, sizeof(int));
 403
 404         switch (optname) {
 405         case WPAN_WANTACK:
 406                 val = ro->want_ack;
 407                 break;
 408         default:
 409                 return -ENOPROTOOPT;
 410         }
 411
 412         if (put_user(len, optlen))
 413                 return -EFAULT;
 414         if (copy_to_user(optval, &val, len))
 415                 return -EFAULT;
 416         return 0;
 417 }
 418
 419 static int dgram_setsockopt(struct sock *sk, int level, int optname,
 420                     char __user *optval, unsigned int optlen)
 421 {
 422         struct dgram_sock *ro = dgram_sk(sk);
 423         int val;
 424         int err = 0;
 425
 426         if (optlen < sizeof(int))
 427                 return -EINVAL;
 428
 429         if (get_user(val, (int __user *)optval))
 430                 return -EFAULT;
 431
 432         lock_sock(sk);
 433
 434         switch (optname) {
 435         case WPAN_WANTACK:
 436                 ro->want_ack = !!val;
 437                 break;
 438         default:
 439                 err = -ENOPROTOOPT;
 440                 break;
 441         }
 442
 443         release_sock(sk);
 444         return err;
 445 }
 446
 447 struct proto ieee802154_dgram_prot = {
 448         .name           = "IEEE-802.15.4-MAC",
 449         .owner          = THIS_MODULE,
 450         .obj_size       = sizeof(struct dgram_sock),
 451         .init           = dgram_init,
 452         .close          = dgram_close,
 453         .bind           = dgram_bind,
 454         .sendmsg        = dgram_sendmsg,
 455         .recvmsg        = dgram_recvmsg,
 456         .hash           = dgram_hash,
 457         .unhash         = dgram_unhash,
 458         .connect        = dgram_connect,
 459         .disconnect     = dgram_disconnect,
 460         .ioctl          = dgram_ioctl,
 461         .getsockopt     = dgram_getsockopt,
 462         .setsockopt     = dgram_setsockopt,
 463 };
 464