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  * Written by:
  16  * Sergey Lapin <slapin@ossfans.org>
  17  * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
  18  */
  19
  20 #include <linux/capability.h>
  21 #include <linux/net.h>
  22 #include <linux/module.h>
  23 #include <linux/if_arp.h>
  24 #include <linux/list.h>
  25 #include <linux/slab.h>
  26 #include <linux/ieee802154.h>
  27 #include <net/sock.h>
  28 #include <net/af_ieee802154.h>
  29 #include <net/ieee802154_netdev.h>
  30
  31 #include <asm/ioctls.h>
  32
  33 #include "af802154.h"
  34
  35 static HLIST_HEAD(dgram_head);
  36 static DEFINE_RWLOCK(dgram_lock);
  37
  38 struct dgram_sock {
  39         struct sock sk;
  40
  41         struct ieee802154_addr src_addr;
  42         struct ieee802154_addr dst_addr;
  43
  44         unsigned int bound:1;
  45         unsigned int connected:1;
  46         unsigned int want_ack:1;
  47         unsigned int secen:1;
  48         unsigned int secen_override:1;
  49         unsigned int seclevel:3;
  50         unsigned int seclevel_override:1;
  51 };
  52
  53 static inline struct dgram_sock *dgram_sk(const struct sock *sk)
  54 {
  55         return container_of(sk, struct dgram_sock, sk);
  56 }
  57
  58 static void dgram_hash(struct sock *sk)
  59 {
  60         write_lock_bh(&dgram_lock);
  61         sk_add_node(sk, &dgram_head);
  62         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  63         write_unlock_bh(&dgram_lock);
  64 }
  65
  66 static void dgram_unhash(struct sock *sk)
  67 {
  68         write_lock_bh(&dgram_lock);
  69         if (sk_del_node_init(sk))
  70                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
  71         write_unlock_bh(&dgram_lock);
  72 }
  73
  74 static int dgram_init(struct sock *sk)
  75 {
  76         struct dgram_sock *ro = dgram_sk(sk);
  77
  78         ro->want_ack = 1;
  79         return 0;
  80 }
  81
  82 static void dgram_close(struct sock *sk, long timeout)
  83 {
  84         sk_common_release(sk);
  85 }
  86
  87 static int dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len)
  88 {
  89         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
  90         struct ieee802154_addr haddr;
  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         ieee802154_addr_from_sa(&haddr, &addr->addr);
 106         dev = ieee802154_get_dev(sock_net(sk), &haddr);
 107         if (!dev) {
 108                 err = -ENODEV;
 109                 goto out;
 110         }
 111
 112         if (dev->type != ARPHRD_IEEE802154) {
 113                 err = -ENODEV;
 114                 goto out_put;
 115         }
 116
 117         ro->src_addr = haddr;
 118
 119         ro->bound = 1;
 120         err = 0;
 121 out_put:
 122         dev_put(dev);
 123 out:
 124         release_sock(sk);
 125
 126         return err;
 127 }
 128
 129 static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
 130 {
 131         switch (cmd) {
 132         case SIOCOUTQ:
 133         {
 134                 int amount = sk_wmem_alloc_get(sk);
 135
 136                 return put_user(amount, (int __user *)arg);
 137         }
 138
 139         case SIOCINQ:
 140         {
 141                 struct sk_buff *skb;
 142                 unsigned long amount;
 143
 144                 amount = 0;
 145                 spin_lock_bh(&sk->sk_receive_queue.lock);
 146                 skb = skb_peek(&sk->sk_receive_queue);
 147                 if (skb != NULL) {
 148                         /* We will only return the amount
 149                          * of this packet since that is all
 150                          * that will be read.
 151                          */
 152                         amount = skb->len - ieee802154_hdr_length(skb);
 153                 }
 154                 spin_unlock_bh(&sk->sk_receive_queue.lock);
 155                 return put_user(amount, (int __user *)arg);
 156         }
 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         ieee802154_addr_from_sa(&ro->dst_addr, &addr->addr);
 185         ro->connected = 1;
 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         ro->connected = 0;
 198         release_sock(sk);
 199
 200         return 0;
 201 }
 202
 203 static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
 204                          struct msghdr *msg, size_t size)
 205 {
 206         struct net_device *dev;
 207         unsigned int mtu;
 208         struct sk_buff *skb;
 209         struct ieee802154_mac_cb *cb;
 210         struct dgram_sock *ro = dgram_sk(sk);
 211         struct ieee802154_addr dst_addr;
 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->connected && !msg->msg_name)
 221                 return -EDESTADDRREQ;
 222         else if (ro->connected && msg->msg_name)
 223                 return -EISCONN;
 224
 225         if (!ro->bound)
 226                 dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
 227         else
 228                 dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
 229
 230         if (!dev) {
 231                 pr_debug("no dev\n");
 232                 err = -ENXIO;
 233                 goto out;
 234         }
 235         mtu = dev->mtu;
 236         pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 237
 238         if (size > mtu) {
 239                 pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 240                 err = -EMSGSIZE;
 241                 goto out_dev;
 242         }
 243
 244         hlen = LL_RESERVED_SPACE(dev);
 245         tlen = dev->needed_tailroom;
 246         skb = sock_alloc_send_skb(sk, hlen + tlen + size,
 247                                   msg->msg_flags & MSG_DONTWAIT,
 248                                   &err);
 249         if (!skb)
 250                 goto out_dev;
 251
 252         skb_reserve(skb, hlen);
 253
 254         skb_reset_network_header(skb);
 255
 256         cb = mac_cb_init(skb);
 257         cb->type = IEEE802154_FC_TYPE_DATA;
 258         cb->ackreq = ro->want_ack;
 259
 260         if (msg->msg_name) {
 261                 DECLARE_SOCKADDR(struct sockaddr_ieee802154*,
 262                                  daddr, msg->msg_name);
 263
 264                 ieee802154_addr_from_sa(&dst_addr, &daddr->addr);
 265         } else {
 266                 dst_addr = ro->dst_addr;
 267         }
 268
 269         cb->secen = ro->secen;
 270         cb->secen_override = ro->secen_override;
 271         cb->seclevel = ro->seclevel;
 272         cb->seclevel_override = ro->seclevel_override;
 273
 274         err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &dst_addr,
 275                               ro->bound ? &ro->src_addr : NULL, size);
 276         if (err < 0)
 277                 goto out_skb;
 278
 279         err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 280         if (err < 0)
 281                 goto out_skb;
 282
 283         skb->dev = dev;
 284         skb->sk  = sk;
 285         skb->protocol = htons(ETH_P_IEEE802154);
 286
 287         dev_put(dev);
 288
 289         err = dev_queue_xmit(skb);
 290         if (err > 0)
 291                 err = net_xmit_errno(err);
 292
 293         return err ?: size;
 294
 295 out_skb:
 296         kfree_skb(skb);
 297 out_dev:
 298         dev_put(dev);
 299 out:
 300         return err;
 301 }
 302
 303 static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
 304                          struct msghdr *msg, size_t len, int noblock,
 305                          int flags, int *addr_len)
 306 {
 307         size_t copied = 0;
 308         int err = -EOPNOTSUPP;
 309         struct sk_buff *skb;
 310         DECLARE_SOCKADDR(struct sockaddr_ieee802154 *, saddr, msg->msg_name);
 311
 312         skb = skb_recv_datagram(sk, flags, noblock, &err);
 313         if (!skb)
 314                 goto out;
 315
 316         copied = skb->len;
 317         if (len < copied) {
 318                 msg->msg_flags |= MSG_TRUNC;
 319                 copied = len;
 320         }
 321
 322         /* FIXME: skip headers if necessary ?! */
 323         err = skb_copy_datagram_msg(skb, 0, msg, copied);
 324         if (err)
 325                 goto done;
 326
 327         sock_recv_ts_and_drops(msg, sk, skb);
 328
 329         if (saddr) {
 330                 saddr->family = AF_IEEE802154;
 331                 ieee802154_addr_to_sa(&saddr->addr, &mac_cb(skb)->source);
 332                 *addr_len = sizeof(*saddr);
 333         }
 334
 335         if (flags & MSG_TRUNC)
 336                 copied = skb->len;
 337 done:
 338         skb_free_datagram(sk, skb);
 339 out:
 340         if (err)
 341                 return err;
 342         return copied;
 343 }
 344
 345 static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
 346 {
 347         skb = skb_share_check(skb, GFP_ATOMIC);
 348         if (!skb)
 349                 return NET_RX_DROP;
 350
 351         if (sock_queue_rcv_skb(sk, skb) < 0) {
 352                 kfree_skb(skb);
 353                 return NET_RX_DROP;
 354         }
 355
 356         return NET_RX_SUCCESS;
 357 }
 358
 359 static inline bool
 360 ieee802154_match_sock(__le64 hw_addr, __le16 pan_id, __le16 short_addr,
 361                       struct dgram_sock *ro)
 362 {
 363         if (!ro->bound)
 364                 return true;
 365
 366         if (ro->src_addr.mode == IEEE802154_ADDR_LONG &&
 367             hw_addr == ro->src_addr.extended_addr)
 368                 return true;
 369
 370         if (ro->src_addr.mode == IEEE802154_ADDR_SHORT &&
 371             pan_id == ro->src_addr.pan_id &&
 372             short_addr == ro->src_addr.short_addr)
 373                 return true;
 374
 375         return false;
 376 }
 377
 378 int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
 379 {
 380         struct sock *sk, *prev = NULL;
 381         int ret = NET_RX_SUCCESS;
 382         __le16 pan_id, short_addr;
 383         __le64 hw_addr;
 384
 385         /* Data frame processing */
 386         BUG_ON(dev->type != ARPHRD_IEEE802154);
 387
 388         pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 389         short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
 390         hw_addr = ieee802154_devaddr_from_raw(dev->dev_addr);
 391
 392         read_lock(&dgram_lock);
 393         sk_for_each(sk, &dgram_head) {
 394                 if (ieee802154_match_sock(hw_addr, pan_id, short_addr,
 395                                           dgram_sk(sk))) {
 396                         if (prev) {
 397                                 struct sk_buff *clone;
 398
 399                                 clone = skb_clone(skb, GFP_ATOMIC);
 400                                 if (clone)
 401                                         dgram_rcv_skb(prev, clone);
 402                         }
 403
 404                         prev = sk;
 405                 }
 406         }
 407
 408         if (prev) {
 409                 dgram_rcv_skb(prev, skb);
 410         } else {
 411                 kfree_skb(skb);
 412                 ret = NET_RX_DROP;
 413         }
 414         read_unlock(&dgram_lock);
 415
 416         return ret;
 417 }
 418
 419 static int dgram_getsockopt(struct sock *sk, int level, int optname,
 420                             char __user *optval, int __user *optlen)
 421 {
 422         struct dgram_sock *ro = dgram_sk(sk);
 423
 424         int val, len;
 425
 426         if (level != SOL_IEEE802154)
 427                 return -EOPNOTSUPP;
 428
 429         if (get_user(len, optlen))
 430                 return -EFAULT;
 431
 432         len = min_t(unsigned int, len, sizeof(int));
 433
 434         switch (optname) {
 435         case WPAN_WANTACK:
 436                 val = ro->want_ack;
 437                 break;
 438         case WPAN_SECURITY:
 439                 if (!ro->secen_override)
 440                         val = WPAN_SECURITY_DEFAULT;
 441                 else if (ro->secen)
 442                         val = WPAN_SECURITY_ON;
 443                 else
 444                         val = WPAN_SECURITY_OFF;
 445                 break;
 446         case WPAN_SECURITY_LEVEL:
 447                 if (!ro->seclevel_override)
 448                         val = WPAN_SECURITY_LEVEL_DEFAULT;
 449                 else
 450                         val = ro->seclevel;
 451                 break;
 452         default:
 453                 return -ENOPROTOOPT;
 454         }
 455
 456         if (put_user(len, optlen))
 457                 return -EFAULT;
 458         if (copy_to_user(optval, &val, len))
 459                 return -EFAULT;
 460         return 0;
 461 }
 462
 463 static int dgram_setsockopt(struct sock *sk, int level, int optname,
 464                             char __user *optval, unsigned int optlen)
 465 {
 466         struct dgram_sock *ro = dgram_sk(sk);
 467         struct net *net = sock_net(sk);
 468         int val;
 469         int err = 0;
 470
 471         if (optlen < sizeof(int))
 472                 return -EINVAL;
 473
 474         if (get_user(val, (int __user *)optval))
 475                 return -EFAULT;
 476
 477         lock_sock(sk);
 478
 479         switch (optname) {
 480         case WPAN_WANTACK:
 481                 ro->want_ack = !!val;
 482                 break;
 483         case WPAN_SECURITY:
 484                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
 485                     !ns_capable(net->user_ns, CAP_NET_RAW)) {
 486                         err = -EPERM;
 487                         break;
 488                 }
 489
 490                 switch (val) {
 491                 case WPAN_SECURITY_DEFAULT:
 492                         ro->secen_override = 0;
 493                         break;
 494                 case WPAN_SECURITY_ON:
 495                         ro->secen_override = 1;
 496                         ro->secen = 1;
 497                         break;
 498                 case WPAN_SECURITY_OFF:
 499                         ro->secen_override = 1;
 500                         ro->secen = 0;
 501                         break;
 502                 default:
 503                         err = -EINVAL;
 504                         break;
 505                 }
 506                 break;
 507         case WPAN_SECURITY_LEVEL:
 508                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
 509                     !ns_capable(net->user_ns, CAP_NET_RAW)) {
 510                         err = -EPERM;
 511                         break;
 512                 }
 513
 514                 if (val < WPAN_SECURITY_LEVEL_DEFAULT ||
 515                     val > IEEE802154_SCF_SECLEVEL_ENC_MIC128) {
 516                         err = -EINVAL;
 517                 } else if (val == WPAN_SECURITY_LEVEL_DEFAULT) {
 518                         ro->seclevel_override = 0;
 519                 } else {
 520                         ro->seclevel_override = 1;
 521                         ro->seclevel = val;
 522                 }
 523                 break;
 524         default:
 525                 err = -ENOPROTOOPT;
 526                 break;
 527         }
 528
 529         release_sock(sk);
 530         return err;
 531 }
 532
 533 struct proto ieee802154_dgram_prot = {
 534         .name           = "IEEE-802.15.4-MAC",
 535         .owner          = THIS_MODULE,
 536         .obj_size       = sizeof(struct dgram_sock),
 537         .init           = dgram_init,
 538         .close          = dgram_close,
 539         .bind           = dgram_bind,
 540         .sendmsg        = dgram_sendmsg,
 541         .recvmsg        = dgram_recvmsg,
 542         .hash           = dgram_hash,
 543         .unhash         = dgram_unhash,
 544         .connect        = dgram_connect,
 545         .disconnect     = dgram_disconnect,
 546         .ioctl          = dgram_ioctl,
 547         .getsockopt     = dgram_getsockopt,
 548         .setsockopt     = dgram_setsockopt,
 549 };
 550