net/ipv6/datagram.c

   1 /*
   2  *      common UDP/RAW code
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      $Id: datagram.c,v 1.24 2002/02/01 22:01:04 davem Exp $
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      as published by the Free Software Foundation; either version
  13  *      2 of the License, or (at your option) any later version.
  14  */
  15
  16 #include <linux/errno.h>
  17 #include <linux/types.h>
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/socket.h>
  22 #include <linux/sockios.h>
  23 #include <linux/in6.h>
  24 #include <linux/ipv6.h>
  25 #include <linux/route.h>
  26
  27 #include <net/ipv6.h>
  28 #include <net/ndisc.h>
  29 #include <net/addrconf.h>
  30 #include <net/transp_v6.h>
  31 #include <net/ip6_route.h>
  32
  33 #include <linux/errqueue.h>
  34 #include <asm/uaccess.h>
  35
  36 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
  37 {
  38         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
  39         struct inet_opt         *inet = inet_sk(sk);
  40         struct ipv6_pinfo       *np = inet6_sk(sk);
  41         struct in6_addr         *daddr;
  42         struct dst_entry        *dst;
  43         struct flowi            fl;
  44         struct ip6_flowlabel    *flowlabel = NULL;
  45         int                     addr_type;
  46         int                     err;
  47
  48         if (usin->sin6_family == AF_INET) {
  49                 if (__ipv6_only_sock(sk))
  50                         return -EAFNOSUPPORT;
  51                 err = ip4_datagram_connect(sk, uaddr, addr_len);
  52                 goto ipv4_connected;
  53         }
  54
  55         if (addr_len < SIN6_LEN_RFC2133)
  56                 return -EINVAL;
  57
  58         if (usin->sin6_family != AF_INET6)
  59                 return -EAFNOSUPPORT;
  60
  61         memset(&fl, 0, sizeof(fl));
  62         if (np->sndflow) {
  63                 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
  64                 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
  65                         flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
  66                         if (flowlabel == NULL)
  67                                 return -EINVAL;
  68                         ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
  69                 }
  70         }
  71
  72         addr_type = ipv6_addr_type(&usin->sin6_addr);
  73
  74         if (addr_type == IPV6_ADDR_ANY) {
  75                 /*
  76                  *      connect to self
  77                  */
  78                 usin->sin6_addr.s6_addr[15] = 0x01;
  79         }
  80
  81         daddr = &usin->sin6_addr;
  82
  83         if (addr_type == IPV6_ADDR_MAPPED) {
  84                 struct sockaddr_in sin;
  85
  86                 if (__ipv6_only_sock(sk)) {
  87                         err = -ENETUNREACH;
  88                         goto out;
  89                 }
  90                 sin.sin_family = AF_INET;
  91                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
  92                 sin.sin_port = usin->sin6_port;
  93
  94                 err = ip4_datagram_connect(sk,
  95                                            (struct sockaddr*) &sin,
  96                                            sizeof(sin));
  97
  98 ipv4_connected:
  99                 if (err)
 100                         goto out;
 101
 102                 ipv6_addr_set(&np->daddr, 0, 0, htonl(0x0000ffff), inet->daddr);
 103
 104                 if (ipv6_addr_any(&np->saddr)) {
 105                         ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000ffff),
 106                                       inet->saddr);
 107                 }
 108
 109                 if (ipv6_addr_any(&np->rcv_saddr)) {
 110                         ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000ffff),
 111                                       inet->rcv_saddr);
 112                 }
 113                 goto out;
 114         }
 115
 116         if (addr_type&IPV6_ADDR_LINKLOCAL) {
 117                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 118                     usin->sin6_scope_id) {
 119                         if (sk->sk_bound_dev_if &&
 120                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
 121                                 err = -EINVAL;
 122                                 goto out;
 123                         }
 124                         sk->sk_bound_dev_if = usin->sin6_scope_id;
 125                         if (!sk->sk_bound_dev_if &&
 126                             (addr_type & IPV6_ADDR_MULTICAST))
 127                                 fl.oif = np->mcast_oif;
 128                 }
 129
 130                 /* Connect to link-local address requires an interface */
 131                 if (!sk->sk_bound_dev_if) {
 132                         err = -EINVAL;
 133                         goto out;
 134                 }
 135         }
 136
 137         ipv6_addr_copy(&np->daddr, daddr);
 138         np->flow_label = fl.fl6_flowlabel;
 139
 140         inet->dport = usin->sin6_port;
 141
 142         /*
 143          *      Check for a route to destination an obtain the
 144          *      destination cache for it.
 145          */
 146
 147         fl.proto = sk->sk_protocol;
 148         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 149         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
 150         fl.oif = sk->sk_bound_dev_if;
 151         fl.fl_ip_dport = inet->dport;
 152         fl.fl_ip_sport = inet->sport;
 153
 154         if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
 155                 fl.oif = np->mcast_oif;
 156
 157         if (flowlabel) {
 158                 if (flowlabel->opt && flowlabel->opt->srcrt) {
 159                         struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
 160                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 161                 }
 162         } else if (np->opt && np->opt->srcrt) {
 163                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
 164                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 165         }
 166
 167         err = ip6_dst_lookup(sk, &dst, &fl);
 168         if (err)
 169                 goto out;
 170
 171         /* source address lookup done in ip6_dst_lookup */
 172
 173         if (ipv6_addr_any(&np->saddr))
 174                 ipv6_addr_copy(&np->saddr, &fl.fl6_src);
 175
 176         if (ipv6_addr_any(&np->rcv_saddr)) {
 177                 ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
 178                 inet->rcv_saddr = LOOPBACK4_IPV6;
 179         }
 180
 181         ip6_dst_store(sk, dst,
 182                       !ipv6_addr_cmp(&fl.fl6_dst, &np->daddr) ?
 183                       &np->daddr : NULL);
 184
 185         sk->sk_state = TCP_ESTABLISHED;
 186 out:
 187         fl6_sock_release(flowlabel);
 188         return err;
 189 }
 190
 191 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 192                      u16 port, u32 info, u8 *payload)
 193 {
 194         struct ipv6_pinfo *np  = inet6_sk(sk);
 195         struct icmp6hdr *icmph = (struct icmp6hdr *)skb->h.raw;
 196         struct sock_exterr_skb *serr;
 197
 198         if (!np->recverr)
 199                 return;
 200
 201         skb = skb_clone(skb, GFP_ATOMIC);
 202         if (!skb)
 203                 return;
 204
 205         serr = SKB_EXT_ERR(skb);
 206         serr->ee.ee_errno = err;
 207         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
 208         serr->ee.ee_type = icmph->icmp6_type;
 209         serr->ee.ee_code = icmph->icmp6_code;
 210         serr->ee.ee_pad = 0;
 211         serr->ee.ee_info = info;
 212         serr->ee.ee_data = 0;
 213         serr->addr_offset = (u8*)&(((struct ipv6hdr*)(icmph+1))->daddr) - skb->nh.raw;
 214         serr->port = port;
 215
 216         skb->h.raw = payload;
 217         __skb_pull(skb, payload - skb->data);
 218
 219         if (sock_queue_err_skb(sk, skb))
 220                 kfree_skb(skb);
 221 }
 222
 223 void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
 224 {
 225         struct ipv6_pinfo *np = inet6_sk(sk);
 226         struct sock_exterr_skb *serr;
 227         struct ipv6hdr *iph;
 228         struct sk_buff *skb;
 229
 230         if (!np->recverr)
 231                 return;
 232
 233         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 234         if (!skb)
 235                 return;
 236
 237         iph = (struct ipv6hdr*)skb_put(skb, sizeof(struct ipv6hdr));
 238         skb->nh.ipv6h = iph;
 239         ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
 240
 241         serr = SKB_EXT_ERR(skb);
 242         serr->ee.ee_errno = err;
 243         serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 244         serr->ee.ee_type = 0;
 245         serr->ee.ee_code = 0;
 246         serr->ee.ee_pad = 0;
 247         serr->ee.ee_info = info;
 248         serr->ee.ee_data = 0;
 249         serr->addr_offset = (u8*)&iph->daddr - skb->nh.raw;
 250         serr->port = fl->fl_ip_dport;
 251
 252         skb->h.raw = skb->tail;
 253         __skb_pull(skb, skb->tail - skb->data);
 254
 255         if (sock_queue_err_skb(sk, skb))
 256                 kfree_skb(skb);
 257 }
 258
 259 /*
 260  *      Handle MSG_ERRQUEUE
 261  */
 262 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
 263 {
 264         struct ipv6_pinfo *np = inet6_sk(sk);
 265         struct sock_exterr_skb *serr;
 266         struct sk_buff *skb, *skb2;
 267         struct sockaddr_in6 *sin;
 268         struct {
 269                 struct sock_extended_err ee;
 270                 struct sockaddr_in6      offender;
 271         } errhdr;
 272         int err;
 273         int copied;
 274
 275         err = -EAGAIN;
 276         skb = skb_dequeue(&sk->sk_error_queue);
 277         if (skb == NULL)
 278                 goto out;
 279
 280         copied = skb->len;
 281         if (copied > len) {
 282                 msg->msg_flags |= MSG_TRUNC;
 283                 copied = len;
 284         }
 285         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 286         if (err)
 287                 goto out_free_skb;
 288
 289         sock_recv_timestamp(msg, sk, skb);
 290
 291         serr = SKB_EXT_ERR(skb);
 292
 293         sin = (struct sockaddr_in6 *)msg->msg_name;
 294         if (sin) {
 295                 sin->sin6_family = AF_INET6;
 296                 sin->sin6_flowinfo = 0;
 297                 sin->sin6_port = serr->port;
 298                 sin->sin6_scope_id = 0;
 299                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 300                         ipv6_addr_copy(&sin->sin6_addr,
 301                           (struct in6_addr *)(skb->nh.raw + serr->addr_offset));
 302                         if (np->sndflow)
 303                                 sin->sin6_flowinfo = *(u32*)(skb->nh.raw + serr->addr_offset - 24) & IPV6_FLOWINFO_MASK;
 304                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 305                                 sin->sin6_scope_id = IP6CB(skb)->iif;
 306                 } else {
 307                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
 308                                       htonl(0xffff),
 309                                       *(u32*)(skb->nh.raw + serr->addr_offset));
 310                 }
 311         }
 312
 313         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 314         sin = &errhdr.offender;
 315         sin->sin6_family = AF_UNSPEC;
 316         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
 317                 sin->sin6_family = AF_INET6;
 318                 sin->sin6_flowinfo = 0;
 319                 sin->sin6_scope_id = 0;
 320                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 321                         ipv6_addr_copy(&sin->sin6_addr, &skb->nh.ipv6h->saddr);
 322                         if (np->rxopt.all)
 323                                 datagram_recv_ctl(sk, msg, skb);
 324                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 325                                 sin->sin6_scope_id = IP6CB(skb)->iif;
 326                 } else {
 327                         struct inet_opt *inet = inet_sk(sk);
 328
 329                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
 330                                       htonl(0xffff),
 331                                       skb->nh.iph->saddr);
 332                         if (inet->cmsg_flags)
 333                                 ip_cmsg_recv(msg, skb);
 334                 }
 335         }
 336
 337         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
 338
 339         /* Now we could try to dump offended packet options */
 340
 341         msg->msg_flags |= MSG_ERRQUEUE;
 342         err = copied;
 343
 344         /* Reset and regenerate socket error */
 345         spin_lock_irq(&sk->sk_error_queue.lock);
 346         sk->sk_err = 0;
 347         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
 348                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 349                 spin_unlock_irq(&sk->sk_error_queue.lock);
 350                 sk->sk_error_report(sk);
 351         } else {
 352                 spin_unlock_irq(&sk->sk_error_queue.lock);
 353         }
 354
 355 out_free_skb:
 356         kfree_skb(skb);
 357 out:
 358         return err;
 359 }
 360
 361
 362
 363 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
 364 {
 365         struct ipv6_pinfo *np = inet6_sk(sk);
 366         struct inet6_skb_parm *opt = IP6CB(skb);
 367
 368         if (np->rxopt.bits.rxinfo) {
 369                 struct in6_pktinfo src_info;
 370
 371                 src_info.ipi6_ifindex = opt->iif;
 372                 ipv6_addr_copy(&src_info.ipi6_addr, &skb->nh.ipv6h->daddr);
 373                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
 374         }
 375
 376         if (np->rxopt.bits.rxhlim) {
 377                 int hlim = skb->nh.ipv6h->hop_limit;
 378                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 379         }
 380
 381         if (np->rxopt.bits.rxflow && (*(u32*)skb->nh.raw & IPV6_FLOWINFO_MASK)) {
 382                 u32 flowinfo = *(u32*)skb->nh.raw & IPV6_FLOWINFO_MASK;
 383                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 384         }
 385         if (np->rxopt.bits.hopopts && opt->hop) {
 386                 u8 *ptr = skb->nh.raw + opt->hop;
 387                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 388         }
 389         if (np->rxopt.bits.dstopts && opt->dst0) {
 390                 u8 *ptr = skb->nh.raw + opt->dst0;
 391                 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, (ptr[1]+1)<<3, ptr);
 392         }
 393         if (np->rxopt.bits.srcrt && opt->srcrt) {
 394                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(skb->nh.raw + opt->srcrt);
 395                 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 396         }
 397         if (np->rxopt.bits.dstopts && opt->dst1) {
 398                 u8 *ptr = skb->nh.raw + opt->dst1;
 399                 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, (ptr[1]+1)<<3, ptr);
 400         }
 401         return 0;
 402 }
 403
 404 int datagram_send_ctl(struct msghdr *msg, struct flowi *fl,
 405                       struct ipv6_txoptions *opt,
 406                       int *hlimit)
 407 {
 408         struct in6_pktinfo *src_info;
 409         struct cmsghdr *cmsg;
 410         struct ipv6_rt_hdr *rthdr;
 411         struct ipv6_opt_hdr *hdr;
 412         int len;
 413         int err = 0;
 414
 415         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 416                 int addr_type;
 417                 struct net_device *dev = NULL;
 418
 419                 if (cmsg->cmsg_len < sizeof(struct cmsghdr) ||
 420                     (unsigned long)(((char*)cmsg - (char*)msg->msg_control)
 421                                     + cmsg->cmsg_len) > msg->msg_controllen) {
 422                         err = -EINVAL;
 423                         goto exit_f;
 424                 }
 425
 426                 if (cmsg->cmsg_level != SOL_IPV6)
 427                         continue;
 428
 429                 switch (cmsg->cmsg_type) {
 430                 case IPV6_PKTINFO:
 431                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 432                                 err = -EINVAL;
 433                                 goto exit_f;
 434                         }
 435
 436                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 437
 438                         if (src_info->ipi6_ifindex) {
 439                                 if (fl->oif && src_info->ipi6_ifindex != fl->oif)
 440                                         return -EINVAL;
 441                                 fl->oif = src_info->ipi6_ifindex;
 442                         }
 443
 444                         addr_type = ipv6_addr_type(&src_info->ipi6_addr);
 445
 446                         if (addr_type == IPV6_ADDR_ANY)
 447                                 break;
 448
 449                         if (addr_type & IPV6_ADDR_LINKLOCAL) {
 450                                 if (!src_info->ipi6_ifindex)
 451                                         return -EINVAL;
 452                                 else {
 453                                         dev = dev_get_by_index(src_info->ipi6_ifindex);
 454                                         if (!dev)
 455                                                 return -ENODEV;
 456                                 }
 457                         }
 458                         if (!ipv6_chk_addr(&src_info->ipi6_addr, dev, 0)) {
 459                                 if (dev)
 460                                         dev_put(dev);
 461                                 err = -EINVAL;
 462                                 goto exit_f;
 463                         }
 464                         if (dev)
 465                                 dev_put(dev);
 466
 467                         ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
 468                         break;
 469
 470                 case IPV6_FLOWINFO:
 471                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
 472                                 err = -EINVAL;
 473                                 goto exit_f;
 474                         }
 475
 476                         if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
 477                                 if ((fl->fl6_flowlabel^*(u32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
 478                                         err = -EINVAL;
 479                                         goto exit_f;
 480                                 }
 481                         }
 482                         fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(u32 *)CMSG_DATA(cmsg);
 483                         break;
 484
 485                 case IPV6_HOPOPTS:
 486                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 487                                 err = -EINVAL;
 488                                 goto exit_f;
 489                         }
 490
 491                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 492                         len = ((hdr->hdrlen + 1) << 3);
 493                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 494                                 err = -EINVAL;
 495                                 goto exit_f;
 496                         }
 497                         if (!capable(CAP_NET_RAW)) {
 498                                 err = -EPERM;
 499                                 goto exit_f;
 500                         }
 501                         opt->opt_nflen += len;
 502                         opt->hopopt = hdr;
 503                         break;
 504
 505                 case IPV6_DSTOPTS:
 506                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 507                                 err = -EINVAL;
 508                                 goto exit_f;
 509                         }
 510
 511                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 512                         len = ((hdr->hdrlen + 1) << 3);
 513                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 514                                 err = -EINVAL;
 515                                 goto exit_f;
 516                         }
 517                         if (!capable(CAP_NET_RAW)) {
 518                                 err = -EPERM;
 519                                 goto exit_f;
 520                         }
 521                         if (opt->dst1opt) {
 522                                 err = -EINVAL;
 523                                 goto exit_f;
 524                         }
 525                         opt->opt_flen += len;
 526                         opt->dst1opt = hdr;
 527                         break;
 528
 529                 case IPV6_RTHDR:
 530                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
 531                                 err = -EINVAL;
 532                                 goto exit_f;
 533                         }
 534
 535                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
 536
 537                         /*
 538                          *      TYPE 0
 539                          */
 540                         if (rthdr->type) {
 541                                 err = -EINVAL;
 542                                 goto exit_f;
 543                         }
 544
 545                         len = ((rthdr->hdrlen + 1) << 3);
 546
 547                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 548                                 err = -EINVAL;
 549                                 goto exit_f;
 550                         }
 551
 552                         /* segments left must also match */
 553                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
 554                                 err = -EINVAL;
 555                                 goto exit_f;
 556                         }
 557
 558                         opt->opt_nflen += len;
 559                         opt->srcrt = rthdr;
 560
 561                         if (opt->dst1opt) {
 562                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
 563
 564                                 opt->opt_nflen += dsthdrlen;
 565                                 opt->dst0opt = opt->dst1opt;
 566                                 opt->dst1opt = NULL;
 567                                 opt->opt_flen -= dsthdrlen;
 568                         }
 569
 570                         break;
 571
 572                 case IPV6_HOPLIMIT:
 573                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 574                                 err = -EINVAL;
 575                                 goto exit_f;
 576                         }
 577
 578                         *hlimit = *(int *)CMSG_DATA(cmsg);
 579                         break;
 580
 581                 default:
 582                         LIMIT_NETDEBUG(
 583                                 printk(KERN_DEBUG "invalid cmsg type: %d\n", cmsg->cmsg_type));
 584                         err = -EINVAL;
 585                         break;
 586                 };
 587         }
 588
 589 exit_f:
 590         return err;
 591 }