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 = sk_wmem_alloc_get(sk);
 130
 131                 return put_user(amount, (int __user *)arg);
 132         }
 133
 134         case SIOCINQ:
 135         {
 136                 struct sk_buff *skb;
 137                 unsigned long amount;
 138
 139                 amount = 0;
 140                 spin_lock_bh(&sk->sk_receive_queue.lock);
 141                 skb = skb_peek(&sk->sk_receive_queue);
 142                 if (skb != NULL) {
 143                         /*
 144                          * We will only return the amount
 145                          * of this packet since that is all
 146                          * that will be read.
 147                          */
 148                         /* FIXME: parse the header for more correct value */
 149                         amount = skb->len - (3+8+8);
 150                 }
 151                 spin_unlock_bh(&sk->sk_receive_queue.lock);
 152                 return put_user(amount, (int __user *)arg);
 153         }
 154
 155         }
 156         return -ENOIOCTLCMD;
 157 }
 158
 159 /* FIXME: autobind */
 160 static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
 161                         int len)
 162 {
 163         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
 164         struct dgram_sock *ro = dgram_sk(sk);
 165         int err = 0;
 166
 167         if (len < sizeof(*addr))
 168                 return -EINVAL;
 169
 170         if (addr->family != AF_IEEE802154)
 171                 return -EINVAL;
 172
 173         lock_sock(sk);
 174
 175         if (!ro->bound) {
 176                 err = -ENETUNREACH;
 177                 goto out;
 178         }
 179
 180         memcpy(&ro->dst_addr, &addr->addr, sizeof(struct ieee802154_addr));
 181
 182 out:
 183         release_sock(sk);
 184         return err;
 185 }
 186
 187 static int dgram_disconnect(struct sock *sk, int flags)
 188 {
 189         struct dgram_sock *ro = dgram_sk(sk);
 190
 191         lock_sock(sk);
 192
 193         ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
 194         memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
 195
 196         release_sock(sk);
 197
 198         return 0;
 199 }
 200
 201 static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
 202                 struct msghdr *msg, size_t size)
 203 {
 204         struct net_device *dev;
 205         unsigned mtu;
 206         struct sk_buff *skb;
 207         struct dgram_sock *ro = dgram_sk(sk);
 208         int err;
 209
 210         if (msg->msg_flags & MSG_OOB) {
 211                 pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
 212                 return -EOPNOTSUPP;
 213         }
 214
 215         if (!ro->bound)
 216                 dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
 217         else
 218                 dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
 219
 220         if (!dev) {
 221                 pr_debug("no dev\n");
 222                 err = -ENXIO;
 223                 goto out;
 224         }
 225         mtu = dev->mtu;
 226         pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 227
 228         skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + size,
 229                         msg->msg_flags & MSG_DONTWAIT,
 230                         &err);
 231         if (!skb)
 232                 goto out_dev;
 233
 234         skb_reserve(skb, LL_RESERVED_SPACE(dev));
 235
 236         skb_reset_network_header(skb);
 237
 238         mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA | MAC_CB_FLAG_ACKREQ;
 239         mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
 240         err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
 241                         ro->bound ? &ro->src_addr : NULL, size);
 242         if (err < 0)
 243                 goto out_skb;
 244
 245         skb_reset_mac_header(skb);
 246
 247         err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 248         if (err < 0)
 249                 goto out_skb;
 250
 251         if (size > mtu) {
 252                 pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 253                 err = -EINVAL;
 254                 goto out_skb;
 255         }
 256
 257         skb->dev = dev;
 258         skb->sk  = sk;
 259         skb->protocol = htons(ETH_P_IEEE802154);
 260
 261         dev_put(dev);
 262
 263         err = dev_queue_xmit(skb);
 264         if (err > 0)
 265                 err = net_xmit_errno(err);
 266
 267         return err ?: size;
 268
 269 out_skb:
 270         kfree_skb(skb);
 271 out_dev:
 272         dev_put(dev);
 273 out:
 274         return err;
 275 }
 276
 277 static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
 278                 struct msghdr *msg, size_t len, int noblock, int flags,
 279                 int *addr_len)
 280 {
 281         size_t copied = 0;
 282         int err = -EOPNOTSUPP;
 283         struct sk_buff *skb;
 284
 285         skb = skb_recv_datagram(sk, flags, noblock, &err);
 286         if (!skb)
 287                 goto out;
 288
 289         copied = skb->len;
 290         if (len < copied) {
 291                 msg->msg_flags |= MSG_TRUNC;
 292                 copied = len;
 293         }
 294
 295         /* FIXME: skip headers if necessary ?! */
 296         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 297         if (err)
 298                 goto done;
 299
 300         sock_recv_timestamp(msg, sk, skb);
 301
 302         if (flags & MSG_TRUNC)
 303                 copied = skb->len;
 304 done:
 305         skb_free_datagram(sk, skb);
 306 out:
 307         if (err)
 308                 return err;
 309         return copied;
 310 }
 311
 312 static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
 313 {
 314         if (sock_queue_rcv_skb(sk, skb) < 0) {
 315                 atomic_inc(&sk->sk_drops);
 316                 kfree_skb(skb);
 317                 return NET_RX_DROP;
 318         }
 319
 320         return NET_RX_SUCCESS;
 321 }
 322
 323 static inline int ieee802154_match_sock(u8 *hw_addr, u16 pan_id,
 324                 u16 short_addr, struct dgram_sock *ro)
 325 {
 326         if (!ro->bound)
 327                 return 1;
 328
 329         if (ro->src_addr.addr_type == IEEE802154_ADDR_LONG &&
 330             !memcmp(ro->src_addr.hwaddr, hw_addr, IEEE802154_ADDR_LEN))
 331                 return 1;
 332
 333         if (ro->src_addr.addr_type == IEEE802154_ADDR_SHORT &&
 334                      pan_id == ro->src_addr.pan_id &&
 335                      short_addr == ro->src_addr.short_addr)
 336                 return 1;
 337
 338         return 0;
 339 }
 340
 341 int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
 342 {
 343         struct sock *sk, *prev = NULL;
 344         struct hlist_node *node;
 345         int ret = NET_RX_SUCCESS;
 346         u16 pan_id, short_addr;
 347
 348         /* Data frame processing */
 349         BUG_ON(dev->type != ARPHRD_IEEE802154);
 350
 351         pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 352         short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
 353
 354         read_lock(&dgram_lock);
 355         sk_for_each(sk, node, &dgram_head) {
 356                 if (ieee802154_match_sock(dev->dev_addr, pan_id, short_addr,
 357                                         dgram_sk(sk))) {
 358                         if (prev) {
 359                                 struct sk_buff *clone;
 360                                 clone = skb_clone(skb, GFP_ATOMIC);
 361                                 if (clone)
 362                                         dgram_rcv_skb(prev, clone);
 363                         }
 364
 365                         prev = sk;
 366                 }
 367         }
 368
 369         if (prev)
 370                 dgram_rcv_skb(prev, skb);
 371         else {
 372                 kfree_skb(skb);
 373                 ret = NET_RX_DROP;
 374         }
 375         read_unlock(&dgram_lock);
 376
 377         return ret;
 378 }
 379
 380 struct proto ieee802154_dgram_prot = {
 381         .name           = "IEEE-802.15.4-MAC",
 382         .owner          = THIS_MODULE,
 383         .obj_size       = sizeof(struct dgram_sock),
 384         .init           = dgram_init,
 385         .close          = dgram_close,
 386         .bind           = dgram_bind,
 387         .sendmsg        = dgram_sendmsg,
 388         .recvmsg        = dgram_recvmsg,
 389         .hash           = dgram_hash,
 390         .unhash         = dgram_unhash,
 391         .connect        = dgram_connect,
 392         .disconnect     = dgram_disconnect,
 393         .ioctl          = dgram_ioctl,
 394 };
 395