net/ieee802154/dgram.c

   1 /*
   2  * ZigBee 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 <net/sock.h>
  29 #include <net/ieee802154/af_ieee802154.h>
  30 #include <net/ieee802154/mac_def.h>
  31 #include <net/ieee802154/netdevice.h>
  32
  33 #include <asm/ioctls.h>
  34
  35 #include "af802154.h"
  36
  37 static HLIST_HEAD(dgram_head);
  38 static DEFINE_RWLOCK(dgram_lock);
  39
  40 struct dgram_sock {
  41         struct sock sk;
  42
  43         int bound;
  44         struct ieee802154_addr src_addr;
  45         struct ieee802154_addr dst_addr;
  46 };
  47
  48 static inline struct dgram_sock *dgram_sk(const struct sock *sk)
  49 {
  50         return container_of(sk, struct dgram_sock, sk);
  51 }
  52
  53
  54 static void dgram_hash(struct sock *sk)
  55 {
  56         write_lock_bh(&dgram_lock);
  57         sk_add_node(sk, &dgram_head);
  58         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  59         write_unlock_bh(&dgram_lock);
  60 }
  61
  62 static void dgram_unhash(struct sock *sk)
  63 {
  64         write_lock_bh(&dgram_lock);
  65         if (sk_del_node_init(sk))
  66                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
  67         write_unlock_bh(&dgram_lock);
  68 }
  69
  70 static int dgram_init(struct sock *sk)
  71 {
  72         struct dgram_sock *ro = dgram_sk(sk);
  73
  74         ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
  75         ro->dst_addr.pan_id = 0xffff;
  76         memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
  77         return 0;
  78 }
  79
  80 static void dgram_close(struct sock *sk, long timeout)
  81 {
  82         sk_common_release(sk);
  83 }
  84
  85 static int dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len)
  86 {
  87         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
  88         struct dgram_sock *ro = dgram_sk(sk);
  89         int err = 0;
  90         struct net_device *dev;
  91
  92         ro->bound = 0;
  93
  94         if (len < sizeof(*addr))
  95                 return -EINVAL;
  96
  97         if (addr->family != AF_IEEE802154)
  98                 return -EINVAL;
  99
 100         lock_sock(sk);
 101
 102         dev = ieee802154_get_dev(sock_net(sk), &addr->addr);
 103         if (!dev) {
 104                 err = -ENODEV;
 105                 goto out;
 106         }
 107
 108         if (dev->type != ARPHRD_IEEE802154) {
 109                 err = -ENODEV;
 110                 goto out_put;
 111         }
 112
 113         memcpy(&ro->src_addr, &addr->addr, sizeof(struct ieee802154_addr));
 114
 115         ro->bound = 1;
 116 out_put:
 117         dev_put(dev);
 118 out:
 119         release_sock(sk);
 120
 121         return err;
 122 }
 123
 124 static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
 125 {
 126         switch (cmd) {
 127         case SIOCOUTQ:
 128         {
 129                 int amount = atomic_read(&sk->sk_wmem_alloc);
 130                 return put_user(amount, (int __user *)arg);
 131         }
 132
 133         case SIOCINQ:
 134         {
 135                 struct sk_buff *skb;
 136                 unsigned long amount;
 137
 138                 amount = 0;
 139                 spin_lock_bh(&sk->sk_receive_queue.lock);
 140                 skb = skb_peek(&sk->sk_receive_queue);
 141                 if (skb != NULL) {
 142                         /*
 143                          * We will only return the amount
 144                          * of this packet since that is all
 145                          * that will be read.
 146                          */
 147                         /* FIXME: parse the header for more correct value */
 148                         amount = skb->len - (3+8+8);
 149                 }
 150                 spin_unlock_bh(&sk->sk_receive_queue.lock);
 151                 return put_user(amount, (int __user *)arg);
 152         }
 153
 154         }
 155         return -ENOIOCTLCMD;
 156 }
 157
 158 /* FIXME: autobind */
 159 static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
 160                         int len)
 161 {
 162         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
 163         struct dgram_sock *ro = dgram_sk(sk);
 164         int err = 0;
 165
 166         if (len < sizeof(*addr))
 167                 return -EINVAL;
 168
 169         if (addr->family != AF_IEEE802154)
 170                 return -EINVAL;
 171
 172         lock_sock(sk);
 173
 174         if (!ro->bound) {
 175                 err = -ENETUNREACH;
 176                 goto out;
 177         }
 178
 179         memcpy(&ro->dst_addr, &addr->addr, sizeof(struct ieee802154_addr));
 180
 181 out:
 182         release_sock(sk);
 183         return err;
 184 }
 185
 186 static int dgram_disconnect(struct sock *sk, int flags)
 187 {
 188         struct dgram_sock *ro = dgram_sk(sk);
 189
 190         lock_sock(sk);
 191
 192         ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
 193         memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
 194
 195         release_sock(sk);
 196
 197         return 0;
 198 }
 199
 200 static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
 201                 struct msghdr *msg, size_t size)
 202 {
 203         struct net_device *dev;
 204         unsigned mtu;
 205         struct sk_buff *skb;
 206         struct dgram_sock *ro = dgram_sk(sk);
 207         int err;
 208
 209         if (msg->msg_flags & MSG_OOB) {
 210                 pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
 211                 return -EOPNOTSUPP;
 212         }
 213
 214         if (!ro->bound)
 215                 dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
 216         else
 217                 dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
 218
 219         if (!dev) {
 220                 pr_debug("no dev\n");
 221                 err = -ENXIO;
 222                 goto out;
 223         }
 224         mtu = dev->mtu;
 225         pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 226
 227         skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + size,
 228                         msg->msg_flags & MSG_DONTWAIT,
 229                         &err);
 230         if (!skb)
 231                 goto out_dev;
 232
 233         skb_reserve(skb, LL_RESERVED_SPACE(dev));
 234
 235         skb_reset_network_header(skb);
 236
 237         mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA | MAC_CB_FLAG_ACKREQ;
 238         mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
 239         err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
 240                         ro->bound ? &ro->src_addr : NULL, size);
 241         if (err < 0)
 242                 goto out_skb;
 243
 244         skb_reset_mac_header(skb);
 245
 246         err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 247         if (err < 0)
 248                 goto out_skb;
 249
 250         if (size > mtu) {
 251                 pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 252                 err = -EINVAL;
 253                 goto out_skb;
 254         }
 255
 256         skb->dev = dev;
 257         skb->sk  = sk;
 258         skb->protocol = htons(ETH_P_IEEE802154);
 259
 260         dev_put(dev);
 261
 262         err = dev_queue_xmit(skb);
 263         if (err > 0)
 264                 err = net_xmit_errno(err);
 265
 266         return err ?: size;
 267
 268 out_skb:
 269         kfree_skb(skb);
 270 out_dev:
 271         dev_put(dev);
 272 out:
 273         return err;
 274 }
 275
 276 static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
 277                 struct msghdr *msg, size_t len, int noblock, int flags,
 278                 int *addr_len)
 279 {
 280         size_t copied = 0;
 281         int err = -EOPNOTSUPP;
 282         struct sk_buff *skb;
 283
 284         skb = skb_recv_datagram(sk, flags, noblock, &err);
 285         if (!skb)
 286                 goto out;
 287
 288         copied = skb->len;
 289         if (len < copied) {
 290                 msg->msg_flags |= MSG_TRUNC;
 291                 copied = len;
 292         }
 293
 294         /* FIXME: skip headers if necessary ?! */
 295         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 296         if (err)
 297                 goto done;
 298
 299         sock_recv_timestamp(msg, sk, skb);
 300
 301         if (flags & MSG_TRUNC)
 302                 copied = skb->len;
 303 done:
 304         skb_free_datagram(sk, skb);
 305 out:
 306         if (err)
 307                 return err;
 308         return copied;
 309 }
 310
 311 static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
 312 {
 313         if (sock_queue_rcv_skb(sk, skb) < 0) {
 314                 atomic_inc(&sk->sk_drops);
 315                 kfree_skb(skb);
 316                 return NET_RX_DROP;
 317         }
 318
 319         return NET_RX_SUCCESS;
 320 }
 321
 322 static inline int ieee802154_match_sock(u8 *hw_addr, u16 pan_id,
 323                 u16 short_addr, struct dgram_sock *ro)
 324 {
 325         if (!ro->bound)
 326                 return 1;
 327
 328         if (ro->src_addr.addr_type == IEEE802154_ADDR_LONG &&
 329             !memcmp(ro->src_addr.hwaddr, hw_addr, IEEE802154_ADDR_LEN))
 330                 return 1;
 331
 332         if (ro->src_addr.addr_type == IEEE802154_ADDR_SHORT &&
 333                      pan_id == ro->src_addr.pan_id &&
 334                      short_addr == ro->src_addr.short_addr)
 335                 return 1;
 336
 337         return 0;
 338 }
 339
 340 int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
 341 {
 342         struct sock *sk, *prev = NULL;
 343         struct hlist_node *node;
 344         int ret = NET_RX_SUCCESS;
 345         u16 pan_id, short_addr;
 346
 347         /* Data frame processing */
 348         BUG_ON(dev->type != ARPHRD_IEEE802154);
 349
 350         pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 351         short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
 352
 353         read_lock(&dgram_lock);
 354         sk_for_each(sk, node, &dgram_head) {
 355                 if (ieee802154_match_sock(dev->dev_addr, pan_id, short_addr,
 356                                         dgram_sk(sk))) {
 357                         if (prev) {
 358                                 struct sk_buff *clone;
 359                                 clone = skb_clone(skb, GFP_ATOMIC);
 360                                 if (clone)
 361                                         dgram_rcv_skb(prev, clone);
 362                         }
 363
 364                         prev = sk;
 365                 }
 366         }
 367
 368         if (prev)
 369                 dgram_rcv_skb(prev, skb);
 370         else {
 371                 kfree_skb(skb);
 372                 ret = NET_RX_DROP;
 373         }
 374         read_unlock(&dgram_lock);
 375
 376         return ret;
 377 }
 378
 379 struct proto ieee802154_dgram_prot = {
 380         .name           = "IEEE-802.15.4-MAC",
 381         .owner          = THIS_MODULE,
 382         .obj_size       = sizeof(struct dgram_sock),
 383         .init           = dgram_init,
 384         .close          = dgram_close,
 385         .bind           = dgram_bind,
 386         .sendmsg        = dgram_sendmsg,
 387         .recvmsg        = dgram_recvmsg,
 388         .hash           = dgram_hash,
 389         .unhash         = dgram_unhash,
 390         .connect        = dgram_connect,
 391         .disconnect     = dgram_disconnect,
 392         .ioctl          = dgram_ioctl,
 393 };
 394