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         return -ENOIOCTLCMD;
 160 }
 161
 162 /* FIXME: autobind */
 163 static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
 164                          int len)
 165 {
 166         struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
 167         struct dgram_sock *ro = dgram_sk(sk);
 168         int err = 0;
 169
 170         if (len < sizeof(*addr))
 171                 return -EINVAL;
 172
 173         if (addr->family != AF_IEEE802154)
 174                 return -EINVAL;
 175
 176         lock_sock(sk);
 177
 178         if (!ro->bound) {
 179                 err = -ENETUNREACH;
 180                 goto out;
 181         }
 182
 183         ieee802154_addr_from_sa(&ro->dst_addr, &addr->addr);
 184         ro->connected = 1;
 185
 186 out:
 187         release_sock(sk);
 188         return err;
 189 }
 190
 191 static int dgram_disconnect(struct sock *sk, int flags)
 192 {
 193         struct dgram_sock *ro = dgram_sk(sk);
 194
 195         lock_sock(sk);
 196         ro->connected = 0;
 197         release_sock(sk);
 198
 199         return 0;
 200 }
 201
 202 static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
 203                          struct msghdr *msg, size_t size)
 204 {
 205         struct net_device *dev;
 206         unsigned int mtu;
 207         struct sk_buff *skb;
 208         struct ieee802154_mac_cb *cb;
 209         struct dgram_sock *ro = dgram_sk(sk);
 210         struct ieee802154_addr dst_addr;
 211         int hlen, tlen;
 212         int err;
 213
 214         if (msg->msg_flags & MSG_OOB) {
 215                 pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
 216                 return -EOPNOTSUPP;
 217         }
 218
 219         if (!ro->connected && !msg->msg_name)
 220                 return -EDESTADDRREQ;
 221         else if (ro->connected && msg->msg_name)
 222                 return -EISCONN;
 223
 224         if (!ro->bound)
 225                 dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
 226         else
 227                 dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
 228
 229         if (!dev) {
 230                 pr_debug("no dev\n");
 231                 err = -ENXIO;
 232                 goto out;
 233         }
 234         mtu = dev->mtu;
 235         pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 236
 237         if (size > mtu) {
 238                 pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 239                 err = -EMSGSIZE;
 240                 goto out_dev;
 241         }
 242
 243         hlen = LL_RESERVED_SPACE(dev);
 244         tlen = dev->needed_tailroom;
 245         skb = sock_alloc_send_skb(sk, hlen + tlen + size,
 246                                   msg->msg_flags & MSG_DONTWAIT,
 247                                   &err);
 248         if (!skb)
 249                 goto out_dev;
 250
 251         skb_reserve(skb, hlen);
 252
 253         skb_reset_network_header(skb);
 254
 255         cb = mac_cb_init(skb);
 256         cb->type = IEEE802154_FC_TYPE_DATA;
 257         cb->ackreq = ro->want_ack;
 258
 259         if (msg->msg_name) {
 260                 DECLARE_SOCKADDR(struct sockaddr_ieee802154*,
 261                                  daddr, msg->msg_name);
 262
 263                 ieee802154_addr_from_sa(&dst_addr, &daddr->addr);
 264         } else {
 265                 dst_addr = ro->dst_addr;
 266         }
 267
 268         cb->secen = ro->secen;
 269         cb->secen_override = ro->secen_override;
 270         cb->seclevel = ro->seclevel;
 271         cb->seclevel_override = ro->seclevel_override;
 272
 273         err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &dst_addr,
 274                               ro->bound ? &ro->src_addr : NULL, size);
 275         if (err < 0)
 276                 goto out_skb;
 277
 278         err = memcpy_from_msg(skb_put(skb, size), msg, size);
 279         if (err < 0)
 280                 goto out_skb;
 281
 282         skb->dev = dev;
 283         skb->sk  = sk;
 284         skb->protocol = htons(ETH_P_IEEE802154);
 285
 286         dev_put(dev);
 287
 288         err = dev_queue_xmit(skb);
 289         if (err > 0)
 290                 err = net_xmit_errno(err);
 291
 292         return err ?: size;
 293
 294 out_skb:
 295         kfree_skb(skb);
 296 out_dev:
 297         dev_put(dev);
 298 out:
 299         return err;
 300 }
 301
 302 static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
 303                          struct msghdr *msg, size_t len, int noblock,
 304                          int flags, int *addr_len)
 305 {
 306         size_t copied = 0;
 307         int err = -EOPNOTSUPP;
 308         struct sk_buff *skb;
 309         DECLARE_SOCKADDR(struct sockaddr_ieee802154 *, saddr, msg->msg_name);
 310
 311         skb = skb_recv_datagram(sk, flags, noblock, &err);
 312         if (!skb)
 313                 goto out;
 314
 315         copied = skb->len;
 316         if (len < copied) {
 317                 msg->msg_flags |= MSG_TRUNC;
 318                 copied = len;
 319         }
 320
 321         /* FIXME: skip headers if necessary ?! */
 322         err = skb_copy_datagram_msg(skb, 0, msg, copied);
 323         if (err)
 324                 goto done;
 325
 326         sock_recv_ts_and_drops(msg, sk, skb);
 327
 328         if (saddr) {
 329                 saddr->family = AF_IEEE802154;
 330                 ieee802154_addr_to_sa(&saddr->addr, &mac_cb(skb)->source);
 331                 *addr_len = sizeof(*saddr);
 332         }
 333
 334         if (flags & MSG_TRUNC)
 335                 copied = skb->len;
 336 done:
 337         skb_free_datagram(sk, skb);
 338 out:
 339         if (err)
 340                 return err;
 341         return copied;
 342 }
 343
 344 static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
 345 {
 346         skb = skb_share_check(skb, GFP_ATOMIC);
 347         if (!skb)
 348                 return NET_RX_DROP;
 349
 350         if (sock_queue_rcv_skb(sk, skb) < 0) {
 351                 kfree_skb(skb);
 352                 return NET_RX_DROP;
 353         }
 354
 355         return NET_RX_SUCCESS;
 356 }
 357
 358 static inline bool
 359 ieee802154_match_sock(__le64 hw_addr, __le16 pan_id, __le16 short_addr,
 360                       struct dgram_sock *ro)
 361 {
 362         if (!ro->bound)
 363                 return true;
 364
 365         if (ro->src_addr.mode == IEEE802154_ADDR_LONG &&
 366             hw_addr == ro->src_addr.extended_addr)
 367                 return true;
 368
 369         if (ro->src_addr.mode == IEEE802154_ADDR_SHORT &&
 370             pan_id == ro->src_addr.pan_id &&
 371             short_addr == ro->src_addr.short_addr)
 372                 return true;
 373
 374         return false;
 375 }
 376
 377 int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
 378 {
 379         struct sock *sk, *prev = NULL;
 380         int ret = NET_RX_SUCCESS;
 381         __le16 pan_id, short_addr;
 382         __le64 hw_addr;
 383
 384         /* Data frame processing */
 385         BUG_ON(dev->type != ARPHRD_IEEE802154);
 386
 387         pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 388         short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
 389         hw_addr = ieee802154_devaddr_from_raw(dev->dev_addr);
 390
 391         read_lock(&dgram_lock);
 392         sk_for_each(sk, &dgram_head) {
 393                 if (ieee802154_match_sock(hw_addr, pan_id, short_addr,
 394                                           dgram_sk(sk))) {
 395                         if (prev) {
 396                                 struct sk_buff *clone;
 397
 398                                 clone = skb_clone(skb, GFP_ATOMIC);
 399                                 if (clone)
 400                                         dgram_rcv_skb(prev, clone);
 401                         }
 402
 403                         prev = sk;
 404                 }
 405         }
 406
 407         if (prev) {
 408                 dgram_rcv_skb(prev, skb);
 409         } else {
 410                 kfree_skb(skb);
 411                 ret = NET_RX_DROP;
 412         }
 413         read_unlock(&dgram_lock);
 414
 415         return ret;
 416 }
 417
 418 static int dgram_getsockopt(struct sock *sk, int level, int optname,
 419                             char __user *optval, int __user *optlen)
 420 {
 421         struct dgram_sock *ro = dgram_sk(sk);
 422
 423         int val, len;
 424
 425         if (level != SOL_IEEE802154)
 426                 return -EOPNOTSUPP;
 427
 428         if (get_user(len, optlen))
 429                 return -EFAULT;
 430
 431         len = min_t(unsigned int, len, sizeof(int));
 432
 433         switch (optname) {
 434         case WPAN_WANTACK:
 435                 val = ro->want_ack;
 436                 break;
 437         case WPAN_SECURITY:
 438                 if (!ro->secen_override)
 439                         val = WPAN_SECURITY_DEFAULT;
 440                 else if (ro->secen)
 441                         val = WPAN_SECURITY_ON;
 442                 else
 443                         val = WPAN_SECURITY_OFF;
 444                 break;
 445         case WPAN_SECURITY_LEVEL:
 446                 if (!ro->seclevel_override)
 447                         val = WPAN_SECURITY_LEVEL_DEFAULT;
 448                 else
 449                         val = ro->seclevel;
 450                 break;
 451         default:
 452                 return -ENOPROTOOPT;
 453         }
 454
 455         if (put_user(len, optlen))
 456                 return -EFAULT;
 457         if (copy_to_user(optval, &val, len))
 458                 return -EFAULT;
 459         return 0;
 460 }
 461
 462 static int dgram_setsockopt(struct sock *sk, int level, int optname,
 463                             char __user *optval, unsigned int optlen)
 464 {
 465         struct dgram_sock *ro = dgram_sk(sk);
 466         struct net *net = sock_net(sk);
 467         int val;
 468         int err = 0;
 469
 470         if (optlen < sizeof(int))
 471                 return -EINVAL;
 472
 473         if (get_user(val, (int __user *)optval))
 474                 return -EFAULT;
 475
 476         lock_sock(sk);
 477
 478         switch (optname) {
 479         case WPAN_WANTACK:
 480                 ro->want_ack = !!val;
 481                 break;
 482         case WPAN_SECURITY:
 483                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
 484                     !ns_capable(net->user_ns, CAP_NET_RAW)) {
 485                         err = -EPERM;
 486                         break;
 487                 }
 488
 489                 switch (val) {
 490                 case WPAN_SECURITY_DEFAULT:
 491                         ro->secen_override = 0;
 492                         break;
 493                 case WPAN_SECURITY_ON:
 494                         ro->secen_override = 1;
 495                         ro->secen = 1;
 496                         break;
 497                 case WPAN_SECURITY_OFF:
 498                         ro->secen_override = 1;
 499                         ro->secen = 0;
 500                         break;
 501                 default:
 502                         err = -EINVAL;
 503                         break;
 504                 }
 505                 break;
 506         case WPAN_SECURITY_LEVEL:
 507                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
 508                     !ns_capable(net->user_ns, CAP_NET_RAW)) {
 509                         err = -EPERM;
 510                         break;
 511                 }
 512
 513                 if (val < WPAN_SECURITY_LEVEL_DEFAULT ||
 514                     val > IEEE802154_SCF_SECLEVEL_ENC_MIC128) {
 515                         err = -EINVAL;
 516                 } else if (val == WPAN_SECURITY_LEVEL_DEFAULT) {
 517                         ro->seclevel_override = 0;
 518                 } else {
 519                         ro->seclevel_override = 1;
 520                         ro->seclevel = val;
 521                 }
 522                 break;
 523         default:
 524                 err = -ENOPROTOOPT;
 525                 break;
 526         }
 527
 528         release_sock(sk);
 529         return err;
 530 }
 531
 532 struct proto ieee802154_dgram_prot = {
 533         .name           = "IEEE-802.15.4-MAC",
 534         .owner          = THIS_MODULE,
 535         .obj_size       = sizeof(struct dgram_sock),
 536         .init           = dgram_init,
 537         .close          = dgram_close,
 538         .bind           = dgram_bind,
 539         .sendmsg        = dgram_sendmsg,
 540         .recvmsg        = dgram_recvmsg,
 541         .hash           = dgram_hash,
 542         .unhash         = dgram_unhash,
 543         .connect        = dgram_connect,
 544         .disconnect     = dgram_disconnect,
 545         .ioctl          = dgram_ioctl,
 546         .getsockopt     = dgram_getsockopt,
 547         .setsockopt     = dgram_setsockopt,
 548 };
 549