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/capability.h>
  25 #include <linux/net.h>
  26 #include <linux/module.h>
  27 #include <linux/if_arp.h>
  28 #include <linux/list.h>
  29 #include <linux/slab.h>
  30 #include <net/sock.h>
  31 #include <net/af_ieee802154.h>
  32 #include <net/ieee802154.h>
  33 #include <net/ieee802154_netdev.h>
  34
  35 #include <asm/ioctls.h>
  36
  37 #include "af802154.h"
  38
  39 static HLIST_HEAD(dgram_head);
  40 static DEFINE_RWLOCK(dgram_lock);
  41
  42 struct dgram_sock {
  43         struct sock sk;
  44
  45         struct ieee802154_addr src_addr;
  46         struct ieee802154_addr dst_addr;
  47
  48         unsigned int bound:1;
  49         unsigned int connected:1;
  50         unsigned int want_ack:1;
  51         unsigned int secen:1;
  52         unsigned int secen_override:1;
  53         unsigned int seclevel:3;
  54         unsigned int seclevel_override:1;
  55 };
  56
  57 static inline struct dgram_sock *dgram_sk(const struct sock *sk)
  58 {
  59         return container_of(sk, struct dgram_sock, sk);
  60 }
  61
  62 static void dgram_hash(struct sock *sk)
  63 {
  64         write_lock_bh(&dgram_lock);
  65         sk_add_node(sk, &dgram_head);
  66         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  67         write_unlock_bh(&dgram_lock);
  68 }
  69
  70 static void dgram_unhash(struct sock *sk)
  71 {
  72         write_lock_bh(&dgram_lock);
  73         if (sk_del_node_init(sk))
  74                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
  75         write_unlock_bh(&dgram_lock);
  76 }
  77
  78 static int dgram_init(struct sock *sk)
  79 {
  80         struct dgram_sock *ro = dgram_sk(sk);
  81
  82         ro->want_ack = 1;
  83         return 0;
  84 }
  85
  86 static void dgram_close(struct sock *sk, long timeout)
  87 {
  88         sk_common_release(sk);
  89 }
  90
  91 static int dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len)
  92 {
  93         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
  94         struct ieee802154_addr haddr;
  95         struct dgram_sock *ro = dgram_sk(sk);
  96         int err = -EINVAL;
  97         struct net_device *dev;
  98
  99         lock_sock(sk);
 100
 101         ro->bound = 0;
 102
 103         if (len < sizeof(*addr))
 104                 goto out;
 105
 106         if (addr->family != AF_IEEE802154)
 107                 goto out;
 108
 109         ieee802154_addr_from_sa(&haddr, &addr->addr);
 110         dev = ieee802154_get_dev(sock_net(sk), &haddr);
 111         if (!dev) {
 112                 err = -ENODEV;
 113                 goto out;
 114         }
 115
 116         if (dev->type != ARPHRD_IEEE802154) {
 117                 err = -ENODEV;
 118                 goto out_put;
 119         }
 120
 121         ro->src_addr = haddr;
 122
 123         ro->bound = 1;
 124         err = 0;
 125 out_put:
 126         dev_put(dev);
 127 out:
 128         release_sock(sk);
 129
 130         return err;
 131 }
 132
 133 static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
 134 {
 135         switch (cmd) {
 136         case SIOCOUTQ:
 137         {
 138                 int amount = sk_wmem_alloc_get(sk);
 139
 140                 return put_user(amount, (int __user *)arg);
 141         }
 142
 143         case SIOCINQ:
 144         {
 145                 struct sk_buff *skb;
 146                 unsigned long amount;
 147
 148                 amount = 0;
 149                 spin_lock_bh(&sk->sk_receive_queue.lock);
 150                 skb = skb_peek(&sk->sk_receive_queue);
 151                 if (skb != NULL) {
 152                         /*
 153                          * We will only return the amount
 154                          * of this packet since that is all
 155                          * that will be read.
 156                          */
 157                         amount = skb->len - ieee802154_hdr_length(skb);
 158                 }
 159                 spin_unlock_bh(&sk->sk_receive_queue.lock);
 160                 return put_user(amount, (int __user *)arg);
 161         }
 162
 163         }
 164         return -ENOIOCTLCMD;
 165 }
 166
 167 /* FIXME: autobind */
 168 static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
 169                         int len)
 170 {
 171         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
 172         struct dgram_sock *ro = dgram_sk(sk);
 173         int err = 0;
 174
 175         if (len < sizeof(*addr))
 176                 return -EINVAL;
 177
 178         if (addr->family != AF_IEEE802154)
 179                 return -EINVAL;
 180
 181         lock_sock(sk);
 182
 183         if (!ro->bound) {
 184                 err = -ENETUNREACH;
 185                 goto out;
 186         }
 187
 188         ieee802154_addr_from_sa(&ro->dst_addr, &addr->addr);
 189         ro->connected = 1;
 190
 191 out:
 192         release_sock(sk);
 193         return err;
 194 }
 195
 196 static int dgram_disconnect(struct sock *sk, int flags)
 197 {
 198         struct dgram_sock *ro = dgram_sk(sk);
 199
 200         lock_sock(sk);
 201         ro->connected = 0;
 202         release_sock(sk);
 203
 204         return 0;
 205 }
 206
 207 static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
 208                 struct msghdr *msg, size_t size)
 209 {
 210         struct net_device *dev;
 211         unsigned int mtu;
 212         struct sk_buff *skb;
 213         struct ieee802154_mac_cb *cb;
 214         struct dgram_sock *ro = dgram_sk(sk);
 215         struct ieee802154_addr dst_addr;
 216         int hlen, tlen;
 217         int err;
 218
 219         if (msg->msg_flags & MSG_OOB) {
 220                 pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
 221                 return -EOPNOTSUPP;
 222         }
 223
 224         if (!ro->connected && !msg->msg_name)
 225                 return -EDESTADDRREQ;
 226         else if (ro->connected && msg->msg_name)
 227                 return -EISCONN;
 228
 229         if (!ro->bound)
 230                 dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
 231         else
 232                 dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
 233
 234         if (!dev) {
 235                 pr_debug("no dev\n");
 236                 err = -ENXIO;
 237                 goto out;
 238         }
 239         mtu = dev->mtu;
 240         pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 241
 242         if (size > mtu) {
 243                 pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 244                 err = -EMSGSIZE;
 245                 goto out_dev;
 246         }
 247
 248         hlen = LL_RESERVED_SPACE(dev);
 249         tlen = dev->needed_tailroom;
 250         skb = sock_alloc_send_skb(sk, hlen + tlen + size,
 251                         msg->msg_flags & MSG_DONTWAIT,
 252                         &err);
 253         if (!skb)
 254                 goto out_dev;
 255
 256         skb_reserve(skb, hlen);
 257
 258         skb_reset_network_header(skb);
 259
 260         cb = mac_cb_init(skb);
 261         cb->type = IEEE802154_FC_TYPE_DATA;
 262         cb->ackreq = ro->want_ack;
 263
 264         if (msg->msg_name) {
 265                 DECLARE_SOCKADDR(struct sockaddr_ieee802154*, daddr, msg->msg_name);
 266
 267                 ieee802154_addr_from_sa(&dst_addr, &daddr->addr);
 268         } else {
 269                 dst_addr = ro->dst_addr;
 270         }
 271
 272         cb->secen = ro->secen;
 273         cb->secen_override = ro->secen_override;
 274         cb->seclevel = ro->seclevel;
 275         cb->seclevel_override = ro->seclevel_override;
 276
 277         err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &dst_addr,
 278                               ro->bound ? &ro->src_addr : NULL, size);
 279         if (err < 0)
 280                 goto out_skb;
 281
 282         err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 283         if (err < 0)
 284                 goto out_skb;
 285
 286         skb->dev = dev;
 287         skb->sk  = sk;
 288         skb->protocol = htons(ETH_P_IEEE802154);
 289
 290         dev_put(dev);
 291
 292         err = dev_queue_xmit(skb);
 293         if (err > 0)
 294                 err = net_xmit_errno(err);
 295
 296         return err ?: size;
 297
 298 out_skb:
 299         kfree_skb(skb);
 300 out_dev:
 301         dev_put(dev);
 302 out:
 303         return err;
 304 }
 305
 306 static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
 307                 struct msghdr *msg, size_t len, int noblock, int flags,
 308                 int *addr_len)
 309 {
 310         size_t copied = 0;
 311         int err = -EOPNOTSUPP;
 312         struct sk_buff *skb;
 313         DECLARE_SOCKADDR(struct sockaddr_ieee802154 *, saddr, msg->msg_name);
 314
 315         skb = skb_recv_datagram(sk, flags, noblock, &err);
 316         if (!skb)
 317                 goto out;
 318
 319         copied = skb->len;
 320         if (len < copied) {
 321                 msg->msg_flags |= MSG_TRUNC;
 322                 copied = len;
 323         }
 324
 325         /* FIXME: skip headers if necessary ?! */
 326         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 327         if (err)
 328                 goto done;
 329
 330         sock_recv_ts_and_drops(msg, sk, skb);
 331
 332         if (saddr) {
 333                 saddr->family = AF_IEEE802154;
 334                 ieee802154_addr_to_sa(&saddr->addr, &mac_cb(skb)->source);
 335                 *addr_len = sizeof(*saddr);
 336         }
 337
 338         if (flags & MSG_TRUNC)
 339                 copied = skb->len;
 340 done:
 341         skb_free_datagram(sk, skb);
 342 out:
 343         if (err)
 344                 return err;
 345         return copied;
 346 }
 347
 348 static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
 349 {
 350         skb = skb_share_check(skb, GFP_ATOMIC);
 351         if (!skb)
 352                 return NET_RX_DROP;
 353
 354         if (sock_queue_rcv_skb(sk, skb) < 0) {
 355                 kfree_skb(skb);
 356                 return NET_RX_DROP;
 357         }
 358
 359         return NET_RX_SUCCESS;
 360 }
 361
 362 static inline bool
 363 ieee802154_match_sock(__le64 hw_addr, __le16 pan_id, __le16 short_addr,
 364                       struct dgram_sock *ro)
 365 {
 366         if (!ro->bound)
 367                 return true;
 368
 369         if (ro->src_addr.mode == IEEE802154_ADDR_LONG &&
 370             hw_addr == ro->src_addr.extended_addr)
 371                 return true;
 372
 373         if (ro->src_addr.mode == IEEE802154_ADDR_SHORT &&
 374             pan_id == ro->src_addr.pan_id &&
 375             short_addr == ro->src_addr.short_addr)
 376                 return true;
 377
 378         return false;
 379 }
 380
 381 int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
 382 {
 383         struct sock *sk, *prev = NULL;
 384         int ret = NET_RX_SUCCESS;
 385         __le16 pan_id, short_addr;
 386         __le64 hw_addr;
 387
 388         /* Data frame processing */
 389         BUG_ON(dev->type != ARPHRD_IEEE802154);
 390
 391         pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 392         short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
 393         hw_addr = ieee802154_devaddr_from_raw(dev->dev_addr);
 394
 395         read_lock(&dgram_lock);
 396         sk_for_each(sk, &dgram_head) {
 397                 if (ieee802154_match_sock(hw_addr, pan_id, short_addr,
 398                                           dgram_sk(sk))) {
 399                         if (prev) {
 400                                 struct sk_buff *clone;
 401                                 clone = skb_clone(skb, GFP_ATOMIC);
 402                                 if (clone)
 403                                         dgram_rcv_skb(prev, clone);
 404                         }
 405
 406                         prev = sk;
 407                 }
 408         }
 409
 410         if (prev)
 411                 dgram_rcv_skb(prev, skb);
 412         else {
 413                 kfree_skb(skb);
 414                 ret = NET_RX_DROP;
 415         }
 416         read_unlock(&dgram_lock);
 417
 418         return ret;
 419 }
 420
 421 static int dgram_getsockopt(struct sock *sk, int level, int optname,
 422                     char __user *optval, int __user *optlen)
 423 {
 424         struct dgram_sock *ro = dgram_sk(sk);
 425
 426         int val, len;
 427
 428         if (level != SOL_IEEE802154)
 429                 return -EOPNOTSUPP;
 430
 431         if (get_user(len, optlen))
 432                 return -EFAULT;
 433
 434         len = min_t(unsigned int, len, sizeof(int));
 435
 436         switch (optname) {
 437         case WPAN_WANTACK:
 438                 val = ro->want_ack;
 439                 break;
 440         case WPAN_SECURITY:
 441                 if (!ro->secen_override)
 442                         val = WPAN_SECURITY_DEFAULT;
 443                 else if (ro->secen)
 444                         val = WPAN_SECURITY_ON;
 445                 else
 446                         val = WPAN_SECURITY_OFF;
 447                 break;
 448         case WPAN_SECURITY_LEVEL:
 449                 if (!ro->seclevel_override)
 450                         val = WPAN_SECURITY_LEVEL_DEFAULT;
 451                 else
 452                         val = ro->seclevel;
 453                 break;
 454         default:
 455                 return -ENOPROTOOPT;
 456         }
 457
 458         if (put_user(len, optlen))
 459                 return -EFAULT;
 460         if (copy_to_user(optval, &val, len))
 461                 return -EFAULT;
 462         return 0;
 463 }
 464
 465 static int dgram_setsockopt(struct sock *sk, int level, int optname,
 466                     char __user *optval, unsigned int optlen)
 467 {
 468         struct dgram_sock *ro = dgram_sk(sk);
 469         struct net *net = sock_net(sk);
 470         int val;
 471         int err = 0;
 472
 473         if (optlen < sizeof(int))
 474                 return -EINVAL;
 475
 476         if (get_user(val, (int __user *)optval))
 477                 return -EFAULT;
 478
 479         lock_sock(sk);
 480
 481         switch (optname) {
 482         case WPAN_WANTACK:
 483                 ro->want_ack = !!val;
 484                 break;
 485         case WPAN_SECURITY:
 486                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
 487                     !ns_capable(net->user_ns, CAP_NET_RAW)) {
 488                         err = -EPERM;
 489                         break;
 490                 }
 491
 492                 switch (val) {
 493                 case WPAN_SECURITY_DEFAULT:
 494                         ro->secen_override = 0;
 495                         break;
 496                 case WPAN_SECURITY_ON:
 497                         ro->secen_override = 1;
 498                         ro->secen = 1;
 499                         break;
 500                 case WPAN_SECURITY_OFF:
 501                         ro->secen_override = 1;
 502                         ro->secen = 0;
 503                         break;
 504                 default:
 505                         err = -EINVAL;
 506                         break;
 507                 }
 508                 break;
 509         case WPAN_SECURITY_LEVEL:
 510                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
 511                     !ns_capable(net->user_ns, CAP_NET_RAW)) {
 512                         err = -EPERM;
 513                         break;
 514                 }
 515
 516                 if (val < WPAN_SECURITY_LEVEL_DEFAULT ||
 517                     val > IEEE802154_SCF_SECLEVEL_ENC_MIC128) {
 518                         err = -EINVAL;
 519                 } else if (val == WPAN_SECURITY_LEVEL_DEFAULT) {
 520                         ro->seclevel_override = 0;
 521                 } else {
 522                         ro->seclevel_override = 1;
 523                         ro->seclevel = val;
 524                 }
 525                 break;
 526         default:
 527                 err = -ENOPROTOOPT;
 528                 break;
 529         }
 530
 531         release_sock(sk);
 532         return err;
 533 }
 534
 535 struct proto ieee802154_dgram_prot = {
 536         .name           = "IEEE-802.15.4-MAC",
 537         .owner          = THIS_MODULE,
 538         .obj_size       = sizeof(struct dgram_sock),
 539         .init           = dgram_init,
 540         .close          = dgram_close,
 541         .bind           = dgram_bind,
 542         .sendmsg        = dgram_sendmsg,
 543         .recvmsg        = dgram_recvmsg,
 544         .hash           = dgram_hash,
 545         .unhash         = dgram_unhash,
 546         .connect        = dgram_connect,
 547         .disconnect     = dgram_disconnect,
 548         .ioctl          = dgram_ioctl,
 549         .getsockopt     = dgram_getsockopt,
 550         .setsockopt     = dgram_setsockopt,
 551 };
 552