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.mode = IEEE802154_ADDR_LONG;
  77         ro->dst_addr.pan_id = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
  78         ro->want_ack = 1;
  79         memset(&ro->dst_addr.extended_addr, 0xff, IEEE802154_ADDR_LEN);
  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 ieee802154_addr haddr;
  92         struct dgram_sock *ro = dgram_sk(sk);
  93         int err = -EINVAL;
  94         struct net_device *dev;
  95
  96         lock_sock(sk);
  97
  98         ro->bound = 0;
  99
 100         if (len < sizeof(*addr))
 101                 goto out;
 102
 103         if (addr->family != AF_IEEE802154)
 104                 goto out;
 105
 106         ieee802154_addr_from_sa(&haddr, &addr->addr);
 107         dev = ieee802154_get_dev(sock_net(sk), &haddr);
 108         if (!dev) {
 109                 err = -ENODEV;
 110                 goto out;
 111         }
 112
 113         if (dev->type != ARPHRD_IEEE802154) {
 114                 err = -ENODEV;
 115                 goto out_put;
 116         }
 117
 118         ro->src_addr = haddr;
 119
 120         ro->bound = 1;
 121         err = 0;
 122 out_put:
 123         dev_put(dev);
 124 out:
 125         release_sock(sk);
 126
 127         return err;
 128 }
 129
 130 static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
 131 {
 132         switch (cmd) {
 133         case SIOCOUTQ:
 134         {
 135                 int amount = sk_wmem_alloc_get(sk);
 136
 137                 return put_user(amount, (int __user *)arg);
 138         }
 139
 140         case SIOCINQ:
 141         {
 142                 struct sk_buff *skb;
 143                 unsigned long amount;
 144
 145                 amount = 0;
 146                 spin_lock_bh(&sk->sk_receive_queue.lock);
 147                 skb = skb_peek(&sk->sk_receive_queue);
 148                 if (skb != NULL) {
 149                         /*
 150                          * We will only return the amount
 151                          * of this packet since that is all
 152                          * that will be read.
 153                          */
 154                         amount = skb->len - ieee802154_hdr_length(skb);
 155                 }
 156                 spin_unlock_bh(&sk->sk_receive_queue.lock);
 157                 return put_user(amount, (int __user *)arg);
 158         }
 159
 160         }
 161         return -ENOIOCTLCMD;
 162 }
 163
 164 /* FIXME: autobind */
 165 static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
 166                         int len)
 167 {
 168         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
 169         struct dgram_sock *ro = dgram_sk(sk);
 170         int err = 0;
 171
 172         if (len < sizeof(*addr))
 173                 return -EINVAL;
 174
 175         if (addr->family != AF_IEEE802154)
 176                 return -EINVAL;
 177
 178         lock_sock(sk);
 179
 180         if (!ro->bound) {
 181                 err = -ENETUNREACH;
 182                 goto out;
 183         }
 184
 185         ieee802154_addr_from_sa(&ro->dst_addr, &addr->addr);
 186
 187 out:
 188         release_sock(sk);
 189         return err;
 190 }
 191
 192 static int dgram_disconnect(struct sock *sk, int flags)
 193 {
 194         struct dgram_sock *ro = dgram_sk(sk);
 195
 196         lock_sock(sk);
 197
 198         ro->dst_addr.mode = IEEE802154_ADDR_LONG;
 199         memset(&ro->dst_addr.extended_addr, 0xff, IEEE802154_ADDR_LEN);
 200
 201         release_sock(sk);
 202
 203         return 0;
 204 }
 205
 206 static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
 207                 struct msghdr *msg, size_t size)
 208 {
 209         struct net_device *dev;
 210         unsigned int mtu;
 211         struct sk_buff *skb;
 212         struct dgram_sock *ro = dgram_sk(sk);
 213         int hlen, tlen;
 214         int err;
 215
 216         if (msg->msg_flags & MSG_OOB) {
 217                 pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
 218                 return -EOPNOTSUPP;
 219         }
 220
 221         if (!ro->bound)
 222                 dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
 223         else
 224                 dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
 225
 226         if (!dev) {
 227                 pr_debug("no dev\n");
 228                 err = -ENXIO;
 229                 goto out;
 230         }
 231         mtu = dev->mtu;
 232         pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 233
 234         if (size > mtu) {
 235                 pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 236                 err = -EINVAL;
 237                 goto out_dev;
 238         }
 239
 240         hlen = LL_RESERVED_SPACE(dev);
 241         tlen = dev->needed_tailroom;
 242         skb = sock_alloc_send_skb(sk, hlen + tlen + size,
 243                         msg->msg_flags & MSG_DONTWAIT,
 244                         &err);
 245         if (!skb)
 246                 goto out_dev;
 247
 248         skb_reserve(skb, hlen);
 249
 250         skb_reset_network_header(skb);
 251
 252         mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
 253         if (ro->want_ack)
 254                 mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;
 255
 256         mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
 257         err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
 258                         ro->bound ? &ro->src_addr : NULL, size);
 259         if (err < 0)
 260                 goto out_skb;
 261
 262         skb_reset_mac_header(skb);
 263
 264         err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 265         if (err < 0)
 266                 goto out_skb;
 267
 268         skb->dev = dev;
 269         skb->sk  = sk;
 270         skb->protocol = htons(ETH_P_IEEE802154);
 271
 272         dev_put(dev);
 273
 274         err = dev_queue_xmit(skb);
 275         if (err > 0)
 276                 err = net_xmit_errno(err);
 277
 278         return err ?: size;
 279
 280 out_skb:
 281         kfree_skb(skb);
 282 out_dev:
 283         dev_put(dev);
 284 out:
 285         return err;
 286 }
 287
 288 static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
 289                 struct msghdr *msg, size_t len, int noblock, int flags,
 290                 int *addr_len)
 291 {
 292         size_t copied = 0;
 293         int err = -EOPNOTSUPP;
 294         struct sk_buff *skb;
 295         DECLARE_SOCKADDR(struct sockaddr_ieee802154 *, saddr, msg->msg_name);
 296
 297         skb = skb_recv_datagram(sk, flags, noblock, &err);
 298         if (!skb)
 299                 goto out;
 300
 301         copied = skb->len;
 302         if (len < copied) {
 303                 msg->msg_flags |= MSG_TRUNC;
 304                 copied = len;
 305         }
 306
 307         /* FIXME: skip headers if necessary ?! */
 308         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 309         if (err)
 310                 goto done;
 311
 312         sock_recv_ts_and_drops(msg, sk, skb);
 313
 314         if (saddr) {
 315                 saddr->family = AF_IEEE802154;
 316                 saddr->addr = mac_cb(skb)->sa;
 317                 *addr_len = sizeof(*saddr);
 318         }
 319
 320         if (flags & MSG_TRUNC)
 321                 copied = skb->len;
 322 done:
 323         skb_free_datagram(sk, skb);
 324 out:
 325         if (err)
 326                 return err;
 327         return copied;
 328 }
 329
 330 static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
 331 {
 332         if (sock_queue_rcv_skb(sk, skb) < 0) {
 333                 kfree_skb(skb);
 334                 return NET_RX_DROP;
 335         }
 336
 337         return NET_RX_SUCCESS;
 338 }
 339
 340 static inline bool
 341 ieee802154_match_sock(__le64 hw_addr, __le16 pan_id, __le16 short_addr,
 342                       struct dgram_sock *ro)
 343 {
 344         if (!ro->bound)
 345                 return true;
 346
 347         if (ro->src_addr.mode == IEEE802154_ADDR_LONG &&
 348             hw_addr == ro->src_addr.extended_addr)
 349                 return true;
 350
 351         if (ro->src_addr.mode == IEEE802154_ADDR_SHORT &&
 352             pan_id == ro->src_addr.pan_id &&
 353             short_addr == ro->src_addr.short_addr)
 354                 return true;
 355
 356         return false;
 357 }
 358
 359 int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
 360 {
 361         struct sock *sk, *prev = NULL;
 362         int ret = NET_RX_SUCCESS;
 363         __le16 pan_id, short_addr;
 364         __le64 hw_addr;
 365
 366         /* Data frame processing */
 367         BUG_ON(dev->type != ARPHRD_IEEE802154);
 368
 369         pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 370         short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
 371         hw_addr = ieee802154_devaddr_from_raw(dev->dev_addr);
 372
 373         read_lock(&dgram_lock);
 374         sk_for_each(sk, &dgram_head) {
 375                 if (ieee802154_match_sock(hw_addr, pan_id, short_addr,
 376                                           dgram_sk(sk))) {
 377                         if (prev) {
 378                                 struct sk_buff *clone;
 379                                 clone = skb_clone(skb, GFP_ATOMIC);
 380                                 if (clone)
 381                                         dgram_rcv_skb(prev, clone);
 382                         }
 383
 384                         prev = sk;
 385                 }
 386         }
 387
 388         if (prev)
 389                 dgram_rcv_skb(prev, skb);
 390         else {
 391                 kfree_skb(skb);
 392                 ret = NET_RX_DROP;
 393         }
 394         read_unlock(&dgram_lock);
 395
 396         return ret;
 397 }
 398
 399 static int dgram_getsockopt(struct sock *sk, int level, int optname,
 400                     char __user *optval, int __user *optlen)
 401 {
 402         struct dgram_sock *ro = dgram_sk(sk);
 403
 404         int val, len;
 405
 406         if (level != SOL_IEEE802154)
 407                 return -EOPNOTSUPP;
 408
 409         if (get_user(len, optlen))
 410                 return -EFAULT;
 411
 412         len = min_t(unsigned int, len, sizeof(int));
 413
 414         switch (optname) {
 415         case WPAN_WANTACK:
 416                 val = ro->want_ack;
 417                 break;
 418         default:
 419                 return -ENOPROTOOPT;
 420         }
 421
 422         if (put_user(len, optlen))
 423                 return -EFAULT;
 424         if (copy_to_user(optval, &val, len))
 425                 return -EFAULT;
 426         return 0;
 427 }
 428
 429 static int dgram_setsockopt(struct sock *sk, int level, int optname,
 430                     char __user *optval, unsigned int optlen)
 431 {
 432         struct dgram_sock *ro = dgram_sk(sk);
 433         int val;
 434         int err = 0;
 435
 436         if (optlen < sizeof(int))
 437                 return -EINVAL;
 438
 439         if (get_user(val, (int __user *)optval))
 440                 return -EFAULT;
 441
 442         lock_sock(sk);
 443
 444         switch (optname) {
 445         case WPAN_WANTACK:
 446                 ro->want_ack = !!val;
 447                 break;
 448         default:
 449                 err = -ENOPROTOOPT;
 450                 break;
 451         }
 452
 453         release_sock(sk);
 454         return err;
 455 }
 456
 457 struct proto ieee802154_dgram_prot = {
 458         .name           = "IEEE-802.15.4-MAC",
 459         .owner          = THIS_MODULE,
 460         .obj_size       = sizeof(struct dgram_sock),
 461         .init           = dgram_init,
 462         .close          = dgram_close,
 463         .bind           = dgram_bind,
 464         .sendmsg        = dgram_sendmsg,
 465         .recvmsg        = dgram_recvmsg,
 466         .hash           = dgram_hash,
 467         .unhash         = dgram_unhash,
 468         .connect        = dgram_connect,
 469         .disconnect     = dgram_disconnect,
 470         .ioctl          = dgram_ioctl,
 471         .getsockopt     = dgram_getsockopt,
 472         .setsockopt     = dgram_setsockopt,
 473 };
 474