net/ipv4/ip_sockglue.c

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              The IP to API glue.
   7  *
   8  * Version:     $Id: ip_sockglue.c,v 1.62 2002/02/01 22:01:04 davem Exp $
   9  *
  10  * Authors:     see ip.c
  11  *
  12  * Fixes:
  13  *              Many            :       Split from ip.c , see ip.c for history.
  14  *              Martin Mares    :       TOS setting fixed.
  15  *              Alan Cox        :       Fixed a couple of oopses in Martin's
  16  *                                      TOS tweaks.
  17  *              Mike McLagan    :       Routing by source
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/types.h>
  22 #include <linux/mm.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/ip.h>
  25 #include <linux/icmp.h>
  26 #include <linux/inetdevice.h>
  27 #include <linux/netdevice.h>
  28 #include <net/sock.h>
  29 #include <net/ip.h>
  30 #include <net/icmp.h>
  31 #include <net/tcp_states.h>
  32 #include <linux/udp.h>
  33 #include <linux/igmp.h>
  34 #include <linux/netfilter.h>
  35 #include <linux/route.h>
  36 #include <linux/mroute.h>
  37 #include <net/route.h>
  38 #include <net/xfrm.h>
  39 #include <net/compat.h>
  40 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  41 #include <net/transp_v6.h>
  42 #endif
  43
  44 #include <linux/errqueue.h>
  45 #include <asm/uaccess.h>
  46
  47 #define IP_CMSG_PKTINFO         1
  48 #define IP_CMSG_TTL             2
  49 #define IP_CMSG_TOS             4
  50 #define IP_CMSG_RECVOPTS        8
  51 #define IP_CMSG_RETOPTS         16
  52 #define IP_CMSG_PASSSEC         32
  53
  54 /*
  55  *      SOL_IP control messages.
  56  */
  57
  58 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
  59 {
  60         struct in_pktinfo info;
  61         struct rtable *rt = skb->rtable;
  62
  63         info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
  64         if (rt) {
  65                 info.ipi_ifindex = rt->rt_iif;
  66                 info.ipi_spec_dst.s_addr = rt->rt_spec_dst;
  67         } else {
  68                 info.ipi_ifindex = 0;
  69                 info.ipi_spec_dst.s_addr = 0;
  70         }
  71
  72         put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
  73 }
  74
  75 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
  76 {
  77         int ttl = ip_hdr(skb)->ttl;
  78         put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
  79 }
  80
  81 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
  82 {
  83         put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
  84 }
  85
  86 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
  87 {
  88         if (IPCB(skb)->opt.optlen == 0)
  89                 return;
  90
  91         put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
  92                  ip_hdr(skb) + 1);
  93 }
  94
  95
  96 static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
  97 {
  98         unsigned char optbuf[sizeof(struct ip_options) + 40];
  99         struct ip_options * opt = (struct ip_options*)optbuf;
 100
 101         if (IPCB(skb)->opt.optlen == 0)
 102                 return;
 103
 104         if (ip_options_echo(opt, skb)) {
 105                 msg->msg_flags |= MSG_CTRUNC;
 106                 return;
 107         }
 108         ip_options_undo(opt);
 109
 110         put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
 111 }
 112
 113 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 114 {
 115         char *secdata;
 116         u32 seclen, secid;
 117         int err;
 118
 119         err = security_socket_getpeersec_dgram(NULL, skb, &secid);
 120         if (err)
 121                 return;
 122
 123         err = security_secid_to_secctx(secid, &secdata, &seclen);
 124         if (err)
 125                 return;
 126
 127         put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
 128         security_release_secctx(secdata, seclen);
 129 }
 130
 131
 132 void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
 133 {
 134         struct inet_sock *inet = inet_sk(skb->sk);
 135         unsigned flags = inet->cmsg_flags;
 136
 137         /* Ordered by supposed usage frequency */
 138         if (flags & 1)
 139                 ip_cmsg_recv_pktinfo(msg, skb);
 140         if ((flags>>=1) == 0)
 141                 return;
 142
 143         if (flags & 1)
 144                 ip_cmsg_recv_ttl(msg, skb);
 145         if ((flags>>=1) == 0)
 146                 return;
 147
 148         if (flags & 1)
 149                 ip_cmsg_recv_tos(msg, skb);
 150         if ((flags>>=1) == 0)
 151                 return;
 152
 153         if (flags & 1)
 154                 ip_cmsg_recv_opts(msg, skb);
 155         if ((flags>>=1) == 0)
 156                 return;
 157
 158         if (flags & 1)
 159                 ip_cmsg_recv_retopts(msg, skb);
 160         if ((flags>>=1) == 0)
 161                 return;
 162
 163         if (flags & 1)
 164                 ip_cmsg_recv_security(msg, skb);
 165 }
 166
 167 int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc)
 168 {
 169         int err;
 170         struct cmsghdr *cmsg;
 171
 172         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 173                 if (!CMSG_OK(msg, cmsg))
 174                         return -EINVAL;
 175                 if (cmsg->cmsg_level != SOL_IP)
 176                         continue;
 177                 switch (cmsg->cmsg_type) {
 178                 case IP_RETOPTS:
 179                         err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
 180                         err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg), err < 40 ? err : 40);
 181                         if (err)
 182                                 return err;
 183                         break;
 184                 case IP_PKTINFO:
 185                 {
 186                         struct in_pktinfo *info;
 187                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
 188                                 return -EINVAL;
 189                         info = (struct in_pktinfo *)CMSG_DATA(cmsg);
 190                         ipc->oif = info->ipi_ifindex;
 191                         ipc->addr = info->ipi_spec_dst.s_addr;
 192                         break;
 193                 }
 194                 default:
 195                         return -EINVAL;
 196                 }
 197         }
 198         return 0;
 199 }
 200
 201
 202 /* Special input handler for packets caught by router alert option.
 203    They are selected only by protocol field, and then processed likely
 204    local ones; but only if someone wants them! Otherwise, router
 205    not running rsvpd will kill RSVP.
 206
 207    It is user level problem, what it will make with them.
 208    I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
 209    but receiver should be enough clever f.e. to forward mtrace requests,
 210    sent to multicast group to reach destination designated router.
 211  */
 212 struct ip_ra_chain *ip_ra_chain;
 213 DEFINE_RWLOCK(ip_ra_lock);
 214
 215 int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *))
 216 {
 217         struct ip_ra_chain *ra, *new_ra, **rap;
 218
 219         if (sk->sk_type != SOCK_RAW || inet_sk(sk)->num == IPPROTO_RAW)
 220                 return -EINVAL;
 221
 222         new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
 223
 224         write_lock_bh(&ip_ra_lock);
 225         for (rap = &ip_ra_chain; (ra=*rap) != NULL; rap = &ra->next) {
 226                 if (ra->sk == sk) {
 227                         if (on) {
 228                                 write_unlock_bh(&ip_ra_lock);
 229                                 kfree(new_ra);
 230                                 return -EADDRINUSE;
 231                         }
 232                         *rap = ra->next;
 233                         write_unlock_bh(&ip_ra_lock);
 234
 235                         if (ra->destructor)
 236                                 ra->destructor(sk);
 237                         sock_put(sk);
 238                         kfree(ra);
 239                         return 0;
 240                 }
 241         }
 242         if (new_ra == NULL) {
 243                 write_unlock_bh(&ip_ra_lock);
 244                 return -ENOBUFS;
 245         }
 246         new_ra->sk = sk;
 247         new_ra->destructor = destructor;
 248
 249         new_ra->next = ra;
 250         *rap = new_ra;
 251         sock_hold(sk);
 252         write_unlock_bh(&ip_ra_lock);
 253
 254         return 0;
 255 }
 256
 257 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 258                    __be16 port, u32 info, u8 *payload)
 259 {
 260         struct inet_sock *inet = inet_sk(sk);
 261         struct sock_exterr_skb *serr;
 262
 263         if (!inet->recverr)
 264                 return;
 265
 266         skb = skb_clone(skb, GFP_ATOMIC);
 267         if (!skb)
 268                 return;
 269
 270         serr = SKB_EXT_ERR(skb);
 271         serr->ee.ee_errno = err;
 272         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
 273         serr->ee.ee_type = icmp_hdr(skb)->type;
 274         serr->ee.ee_code = icmp_hdr(skb)->code;
 275         serr->ee.ee_pad = 0;
 276         serr->ee.ee_info = info;
 277         serr->ee.ee_data = 0;
 278         serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
 279                                    skb_network_header(skb);
 280         serr->port = port;
 281
 282         if (skb_pull(skb, payload - skb->data) != NULL) {
 283                 skb_reset_transport_header(skb);
 284                 if (sock_queue_err_skb(sk, skb) == 0)
 285                         return;
 286         }
 287         kfree_skb(skb);
 288 }
 289
 290 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
 291 {
 292         struct inet_sock *inet = inet_sk(sk);
 293         struct sock_exterr_skb *serr;
 294         struct iphdr *iph;
 295         struct sk_buff *skb;
 296
 297         if (!inet->recverr)
 298                 return;
 299
 300         skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
 301         if (!skb)
 302                 return;
 303
 304         skb_put(skb, sizeof(struct iphdr));
 305         skb_reset_network_header(skb);
 306         iph = ip_hdr(skb);
 307         iph->daddr = daddr;
 308
 309         serr = SKB_EXT_ERR(skb);
 310         serr->ee.ee_errno = err;
 311         serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 312         serr->ee.ee_type = 0;
 313         serr->ee.ee_code = 0;
 314         serr->ee.ee_pad = 0;
 315         serr->ee.ee_info = info;
 316         serr->ee.ee_data = 0;
 317         serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 318         serr->port = port;
 319
 320         __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 321         skb_reset_transport_header(skb);
 322
 323         if (sock_queue_err_skb(sk, skb))
 324                 kfree_skb(skb);
 325 }
 326
 327 /*
 328  *      Handle MSG_ERRQUEUE
 329  */
 330 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
 331 {
 332         struct sock_exterr_skb *serr;
 333         struct sk_buff *skb, *skb2;
 334         struct sockaddr_in *sin;
 335         struct {
 336                 struct sock_extended_err ee;
 337                 struct sockaddr_in       offender;
 338         } errhdr;
 339         int err;
 340         int copied;
 341
 342         err = -EAGAIN;
 343         skb = skb_dequeue(&sk->sk_error_queue);
 344         if (skb == NULL)
 345                 goto out;
 346
 347         copied = skb->len;
 348         if (copied > len) {
 349                 msg->msg_flags |= MSG_TRUNC;
 350                 copied = len;
 351         }
 352         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 353         if (err)
 354                 goto out_free_skb;
 355
 356         sock_recv_timestamp(msg, sk, skb);
 357
 358         serr = SKB_EXT_ERR(skb);
 359
 360         sin = (struct sockaddr_in *)msg->msg_name;
 361         if (sin) {
 362                 sin->sin_family = AF_INET;
 363                 sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
 364                                                    serr->addr_offset);
 365                 sin->sin_port = serr->port;
 366                 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
 367         }
 368
 369         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 370         sin = &errhdr.offender;
 371         sin->sin_family = AF_UNSPEC;
 372         if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
 373                 struct inet_sock *inet = inet_sk(sk);
 374
 375                 sin->sin_family = AF_INET;
 376                 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 377                 sin->sin_port = 0;
 378                 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
 379                 if (inet->cmsg_flags)
 380                         ip_cmsg_recv(msg, skb);
 381         }
 382
 383         put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
 384
 385         /* Now we could try to dump offended packet options */
 386
 387         msg->msg_flags |= MSG_ERRQUEUE;
 388         err = copied;
 389
 390         /* Reset and regenerate socket error */
 391         spin_lock_bh(&sk->sk_error_queue.lock);
 392         sk->sk_err = 0;
 393         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
 394                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 395                 spin_unlock_bh(&sk->sk_error_queue.lock);
 396                 sk->sk_error_report(sk);
 397         } else
 398                 spin_unlock_bh(&sk->sk_error_queue.lock);
 399
 400 out_free_skb:
 401         kfree_skb(skb);
 402 out:
 403         return err;
 404 }
 405
 406
 407 /*
 408  *      Socket option code for IP. This is the end of the line after any TCP,UDP etc options on
 409  *      an IP socket.
 410  */
 411
 412 static int do_ip_setsockopt(struct sock *sk, int level,
 413                             int optname, char __user *optval, int optlen)
 414 {
 415         struct inet_sock *inet = inet_sk(sk);
 416         int val=0,err;
 417
 418         if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) |
 419                              (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) |
 420                              (1<<IP_RETOPTS) | (1<<IP_TOS) |
 421                              (1<<IP_TTL) | (1<<IP_HDRINCL) |
 422                              (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) |
 423                              (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND) |
 424                              (1<<IP_PASSSEC))) ||
 425             optname == IP_MULTICAST_TTL ||
 426             optname == IP_MULTICAST_LOOP) {
 427                 if (optlen >= sizeof(int)) {
 428                         if (get_user(val, (int __user *) optval))
 429                                 return -EFAULT;
 430                 } else if (optlen >= sizeof(char)) {
 431                         unsigned char ucval;
 432
 433                         if (get_user(ucval, (unsigned char __user *) optval))
 434                                 return -EFAULT;
 435                         val = (int) ucval;
 436                 }
 437         }
 438
 439         /* If optlen==0, it is equivalent to val == 0 */
 440
 441         if (ip_mroute_opt(optname))
 442                 return ip_mroute_setsockopt(sk,optname,optval,optlen);
 443
 444         err = 0;
 445         lock_sock(sk);
 446
 447         switch (optname) {
 448         case IP_OPTIONS:
 449         {
 450                 struct ip_options * opt = NULL;
 451                 if (optlen > 40 || optlen < 0)
 452                         goto e_inval;
 453                 err = ip_options_get_from_user(sock_net(sk), &opt,
 454                                                optval, optlen);
 455                 if (err)
 456                         break;
 457                 if (inet->is_icsk) {
 458                         struct inet_connection_sock *icsk = inet_csk(sk);
 459 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 460                         if (sk->sk_family == PF_INET ||
 461                             (!((1 << sk->sk_state) &
 462                                (TCPF_LISTEN | TCPF_CLOSE)) &&
 463                              inet->daddr != LOOPBACK4_IPV6)) {
 464 #endif
 465                                 if (inet->opt)
 466                                         icsk->icsk_ext_hdr_len -= inet->opt->optlen;
 467                                 if (opt)
 468                                         icsk->icsk_ext_hdr_len += opt->optlen;
 469                                 icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 470 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 471                         }
 472 #endif
 473                 }
 474                 opt = xchg(&inet->opt, opt);
 475                 kfree(opt);
 476                 break;
 477         }
 478         case IP_PKTINFO:
 479                 if (val)
 480                         inet->cmsg_flags |= IP_CMSG_PKTINFO;
 481                 else
 482                         inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
 483                 break;
 484         case IP_RECVTTL:
 485                 if (val)
 486                         inet->cmsg_flags |=  IP_CMSG_TTL;
 487                 else
 488                         inet->cmsg_flags &= ~IP_CMSG_TTL;
 489                 break;
 490         case IP_RECVTOS:
 491                 if (val)
 492                         inet->cmsg_flags |=  IP_CMSG_TOS;
 493                 else
 494                         inet->cmsg_flags &= ~IP_CMSG_TOS;
 495                 break;
 496         case IP_RECVOPTS:
 497                 if (val)
 498                         inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
 499                 else
 500                         inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
 501                 break;
 502         case IP_RETOPTS:
 503                 if (val)
 504                         inet->cmsg_flags |= IP_CMSG_RETOPTS;
 505                 else
 506                         inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
 507                 break;
 508         case IP_PASSSEC:
 509                 if (val)
 510                         inet->cmsg_flags |= IP_CMSG_PASSSEC;
 511                 else
 512                         inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
 513                 break;
 514         case IP_TOS:    /* This sets both TOS and Precedence */
 515                 if (sk->sk_type == SOCK_STREAM) {
 516                         val &= ~3;
 517                         val |= inet->tos & 3;
 518                 }
 519                 if (inet->tos != val) {
 520                         inet->tos = val;
 521                         sk->sk_priority = rt_tos2priority(val);
 522                         sk_dst_reset(sk);
 523                 }
 524                 break;
 525         case IP_TTL:
 526                 if (optlen<1)
 527                         goto e_inval;
 528                 if (val != -1 && (val < 1 || val>255))
 529                         goto e_inval;
 530                 inet->uc_ttl = val;
 531                 break;
 532         case IP_HDRINCL:
 533                 if (sk->sk_type != SOCK_RAW) {
 534                         err = -ENOPROTOOPT;
 535                         break;
 536                 }
 537                 inet->hdrincl = val ? 1 : 0;
 538                 break;
 539         case IP_MTU_DISCOVER:
 540                 if (val<0 || val>3)
 541                         goto e_inval;
 542                 inet->pmtudisc = val;
 543                 break;
 544         case IP_RECVERR:
 545                 inet->recverr = !!val;
 546                 if (!val)
 547                         skb_queue_purge(&sk->sk_error_queue);
 548                 break;
 549         case IP_MULTICAST_TTL:
 550                 if (sk->sk_type == SOCK_STREAM)
 551                         goto e_inval;
 552                 if (optlen<1)
 553                         goto e_inval;
 554                 if (val==-1)
 555                         val = 1;
 556                 if (val < 0 || val > 255)
 557                         goto e_inval;
 558                 inet->mc_ttl = val;
 559                 break;
 560         case IP_MULTICAST_LOOP:
 561                 if (optlen<1)
 562                         goto e_inval;
 563                 inet->mc_loop = !!val;
 564                 break;
 565         case IP_MULTICAST_IF:
 566         {
 567                 struct ip_mreqn mreq;
 568                 struct net_device *dev = NULL;
 569
 570                 if (sk->sk_type == SOCK_STREAM)
 571                         goto e_inval;
 572                 /*
 573                  *      Check the arguments are allowable
 574                  */
 575
 576                 err = -EFAULT;
 577                 if (optlen >= sizeof(struct ip_mreqn)) {
 578                         if (copy_from_user(&mreq,optval,sizeof(mreq)))
 579                                 break;
 580                 } else {
 581                         memset(&mreq, 0, sizeof(mreq));
 582                         if (optlen >= sizeof(struct in_addr) &&
 583                             copy_from_user(&mreq.imr_address,optval,sizeof(struct in_addr)))
 584                                 break;
 585                 }
 586
 587                 if (!mreq.imr_ifindex) {
 588                         if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
 589                                 inet->mc_index = 0;
 590                                 inet->mc_addr  = 0;
 591                                 err = 0;
 592                                 break;
 593                         }
 594                         dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
 595                         if (dev) {
 596                                 mreq.imr_ifindex = dev->ifindex;
 597                                 dev_put(dev);
 598                         }
 599                 } else
 600                         dev = __dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
 601
 602
 603                 err = -EADDRNOTAVAIL;
 604                 if (!dev)
 605                         break;
 606
 607                 err = -EINVAL;
 608                 if (sk->sk_bound_dev_if &&
 609                     mreq.imr_ifindex != sk->sk_bound_dev_if)
 610                         break;
 611
 612                 inet->mc_index = mreq.imr_ifindex;
 613                 inet->mc_addr  = mreq.imr_address.s_addr;
 614                 err = 0;
 615                 break;
 616         }
 617
 618         case IP_ADD_MEMBERSHIP:
 619         case IP_DROP_MEMBERSHIP:
 620         {
 621                 struct ip_mreqn mreq;
 622
 623                 err = -EPROTO;
 624                 if (inet_sk(sk)->is_icsk)
 625                         break;
 626
 627                 if (optlen < sizeof(struct ip_mreq))
 628                         goto e_inval;
 629                 err = -EFAULT;
 630                 if (optlen >= sizeof(struct ip_mreqn)) {
 631                         if (copy_from_user(&mreq,optval,sizeof(mreq)))
 632                                 break;
 633                 } else {
 634                         memset(&mreq, 0, sizeof(mreq));
 635                         if (copy_from_user(&mreq,optval,sizeof(struct ip_mreq)))
 636                                 break;
 637                 }
 638
 639                 if (optname == IP_ADD_MEMBERSHIP)
 640                         err = ip_mc_join_group(sk, &mreq);
 641                 else
 642                         err = ip_mc_leave_group(sk, &mreq);
 643                 break;
 644         }
 645         case IP_MSFILTER:
 646         {
 647                 extern int sysctl_igmp_max_msf;
 648                 struct ip_msfilter *msf;
 649
 650                 if (optlen < IP_MSFILTER_SIZE(0))
 651                         goto e_inval;
 652                 if (optlen > sysctl_optmem_max) {
 653                         err = -ENOBUFS;
 654                         break;
 655                 }
 656                 msf = kmalloc(optlen, GFP_KERNEL);
 657                 if (!msf) {
 658                         err = -ENOBUFS;
 659                         break;
 660                 }
 661                 err = -EFAULT;
 662                 if (copy_from_user(msf, optval, optlen)) {
 663                         kfree(msf);
 664                         break;
 665                 }
 666                 /* numsrc >= (1G-4) overflow in 32 bits */
 667                 if (msf->imsf_numsrc >= 0x3ffffffcU ||
 668                     msf->imsf_numsrc > sysctl_igmp_max_msf) {
 669                         kfree(msf);
 670                         err = -ENOBUFS;
 671                         break;
 672                 }
 673                 if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
 674                         kfree(msf);
 675                         err = -EINVAL;
 676                         break;
 677                 }
 678                 err = ip_mc_msfilter(sk, msf, 0);
 679                 kfree(msf);
 680                 break;
 681         }
 682         case IP_BLOCK_SOURCE:
 683         case IP_UNBLOCK_SOURCE:
 684         case IP_ADD_SOURCE_MEMBERSHIP:
 685         case IP_DROP_SOURCE_MEMBERSHIP:
 686         {
 687                 struct ip_mreq_source mreqs;
 688                 int omode, add;
 689
 690                 if (optlen != sizeof(struct ip_mreq_source))
 691                         goto e_inval;
 692                 if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
 693                         err = -EFAULT;
 694                         break;
 695                 }
 696                 if (optname == IP_BLOCK_SOURCE) {
 697                         omode = MCAST_EXCLUDE;
 698                         add = 1;
 699                 } else if (optname == IP_UNBLOCK_SOURCE) {
 700                         omode = MCAST_EXCLUDE;
 701                         add = 0;
 702                 } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
 703                         struct ip_mreqn mreq;
 704
 705                         mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
 706                         mreq.imr_address.s_addr = mreqs.imr_interface;
 707                         mreq.imr_ifindex = 0;
 708                         err = ip_mc_join_group(sk, &mreq);
 709                         if (err && err != -EADDRINUSE)
 710                                 break;
 711                         omode = MCAST_INCLUDE;
 712                         add = 1;
 713                 } else /* IP_DROP_SOURCE_MEMBERSHIP */ {
 714                         omode = MCAST_INCLUDE;
 715                         add = 0;
 716                 }
 717                 err = ip_mc_source(add, omode, sk, &mreqs, 0);
 718                 break;
 719         }
 720         case MCAST_JOIN_GROUP:
 721         case MCAST_LEAVE_GROUP:
 722         {
 723                 struct group_req greq;
 724                 struct sockaddr_in *psin;
 725                 struct ip_mreqn mreq;
 726
 727                 if (optlen < sizeof(struct group_req))
 728                         goto e_inval;
 729                 err = -EFAULT;
 730                 if (copy_from_user(&greq, optval, sizeof(greq)))
 731                         break;
 732                 psin = (struct sockaddr_in *)&greq.gr_group;
 733                 if (psin->sin_family != AF_INET)
 734                         goto e_inval;
 735                 memset(&mreq, 0, sizeof(mreq));
 736                 mreq.imr_multiaddr = psin->sin_addr;
 737                 mreq.imr_ifindex = greq.gr_interface;
 738
 739                 if (optname == MCAST_JOIN_GROUP)
 740                         err = ip_mc_join_group(sk, &mreq);
 741                 else
 742                         err = ip_mc_leave_group(sk, &mreq);
 743                 break;
 744         }
 745         case MCAST_JOIN_SOURCE_GROUP:
 746         case MCAST_LEAVE_SOURCE_GROUP:
 747         case MCAST_BLOCK_SOURCE:
 748         case MCAST_UNBLOCK_SOURCE:
 749         {
 750                 struct group_source_req greqs;
 751                 struct ip_mreq_source mreqs;
 752                 struct sockaddr_in *psin;
 753                 int omode, add;
 754
 755                 if (optlen != sizeof(struct group_source_req))
 756                         goto e_inval;
 757                 if (copy_from_user(&greqs, optval, sizeof(greqs))) {
 758                         err = -EFAULT;
 759                         break;
 760                 }
 761                 if (greqs.gsr_group.ss_family != AF_INET ||
 762                     greqs.gsr_source.ss_family != AF_INET) {
 763                         err = -EADDRNOTAVAIL;
 764                         break;
 765                 }
 766                 psin = (struct sockaddr_in *)&greqs.gsr_group;
 767                 mreqs.imr_multiaddr = psin->sin_addr.s_addr;
 768                 psin = (struct sockaddr_in *)&greqs.gsr_source;
 769                 mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
 770                 mreqs.imr_interface = 0; /* use index for mc_source */
 771
 772                 if (optname == MCAST_BLOCK_SOURCE) {
 773                         omode = MCAST_EXCLUDE;
 774                         add = 1;
 775                 } else if (optname == MCAST_UNBLOCK_SOURCE) {
 776                         omode = MCAST_EXCLUDE;
 777                         add = 0;
 778                 } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
 779                         struct ip_mreqn mreq;
 780
 781                         psin = (struct sockaddr_in *)&greqs.gsr_group;
 782                         mreq.imr_multiaddr = psin->sin_addr;
 783                         mreq.imr_address.s_addr = 0;
 784                         mreq.imr_ifindex = greqs.gsr_interface;
 785                         err = ip_mc_join_group(sk, &mreq);
 786                         if (err && err != -EADDRINUSE)
 787                                 break;
 788                         greqs.gsr_interface = mreq.imr_ifindex;
 789                         omode = MCAST_INCLUDE;
 790                         add = 1;
 791                 } else /* MCAST_LEAVE_SOURCE_GROUP */ {
 792                         omode = MCAST_INCLUDE;
 793                         add = 0;
 794                 }
 795                 err = ip_mc_source(add, omode, sk, &mreqs,
 796                                    greqs.gsr_interface);
 797                 break;
 798         }
 799         case MCAST_MSFILTER:
 800         {
 801                 extern int sysctl_igmp_max_msf;
 802                 struct sockaddr_in *psin;
 803                 struct ip_msfilter *msf = NULL;
 804                 struct group_filter *gsf = NULL;
 805                 int msize, i, ifindex;
 806
 807                 if (optlen < GROUP_FILTER_SIZE(0))
 808                         goto e_inval;
 809                 if (optlen > sysctl_optmem_max) {
 810                         err = -ENOBUFS;
 811                         break;
 812                 }
 813                 gsf = kmalloc(optlen,GFP_KERNEL);
 814                 if (!gsf) {
 815                         err = -ENOBUFS;
 816                         break;
 817                 }
 818                 err = -EFAULT;
 819                 if (copy_from_user(gsf, optval, optlen)) {
 820                         goto mc_msf_out;
 821                 }
 822                 /* numsrc >= (4G-140)/128 overflow in 32 bits */
 823                 if (gsf->gf_numsrc >= 0x1ffffff ||
 824                     gsf->gf_numsrc > sysctl_igmp_max_msf) {
 825                         err = -ENOBUFS;
 826                         goto mc_msf_out;
 827                 }
 828                 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
 829                         err = -EINVAL;
 830                         goto mc_msf_out;
 831                 }
 832                 msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
 833                 msf = kmalloc(msize,GFP_KERNEL);
 834                 if (!msf) {
 835                         err = -ENOBUFS;
 836                         goto mc_msf_out;
 837                 }
 838                 ifindex = gsf->gf_interface;
 839                 psin = (struct sockaddr_in *)&gsf->gf_group;
 840                 if (psin->sin_family != AF_INET) {
 841                         err = -EADDRNOTAVAIL;
 842                         goto mc_msf_out;
 843                 }
 844                 msf->imsf_multiaddr = psin->sin_addr.s_addr;
 845                 msf->imsf_interface = 0;
 846                 msf->imsf_fmode = gsf->gf_fmode;
 847                 msf->imsf_numsrc = gsf->gf_numsrc;
 848                 err = -EADDRNOTAVAIL;
 849                 for (i=0; i<gsf->gf_numsrc; ++i) {
 850                         psin = (struct sockaddr_in *)&gsf->gf_slist[i];
 851
 852                         if (psin->sin_family != AF_INET)
 853                                 goto mc_msf_out;
 854                         msf->imsf_slist[i] = psin->sin_addr.s_addr;
 855                 }
 856                 kfree(gsf);
 857                 gsf = NULL;
 858
 859                 err = ip_mc_msfilter(sk, msf, ifindex);
 860         mc_msf_out:
 861                 kfree(msf);
 862                 kfree(gsf);
 863                 break;
 864         }
 865         case IP_ROUTER_ALERT:
 866                 err = ip_ra_control(sk, val ? 1 : 0, NULL);
 867                 break;
 868
 869         case IP_FREEBIND:
 870                 if (optlen<1)
 871                         goto e_inval;
 872                 inet->freebind = !!val;
 873                 break;
 874
 875         case IP_IPSEC_POLICY:
 876         case IP_XFRM_POLICY:
 877                 err = -EPERM;
 878                 if (!capable(CAP_NET_ADMIN))
 879                         break;
 880                 err = xfrm_user_policy(sk, optname, optval, optlen);
 881                 break;
 882
 883         default:
 884                 err = -ENOPROTOOPT;
 885                 break;
 886         }
 887         release_sock(sk);
 888         return err;
 889
 890 e_inval:
 891         release_sock(sk);
 892         return -EINVAL;
 893 }
 894
 895 int ip_setsockopt(struct sock *sk, int level,
 896                 int optname, char __user *optval, int optlen)
 897 {
 898         int err;
 899
 900         if (level != SOL_IP)
 901                 return -ENOPROTOOPT;
 902
 903         err = do_ip_setsockopt(sk, level, optname, optval, optlen);
 904 #ifdef CONFIG_NETFILTER
 905         /* we need to exclude all possible ENOPROTOOPTs except default case */
 906         if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
 907                         optname != IP_IPSEC_POLICY &&
 908                         optname != IP_XFRM_POLICY &&
 909                         !ip_mroute_opt(optname)) {
 910                 lock_sock(sk);
 911                 err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
 912                 release_sock(sk);
 913         }
 914 #endif
 915         return err;
 916 }
 917
 918 #ifdef CONFIG_COMPAT
 919 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
 920                          char __user *optval, int optlen)
 921 {
 922         int err;
 923
 924         if (level != SOL_IP)
 925                 return -ENOPROTOOPT;
 926
 927         if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
 928                 return compat_mc_setsockopt(sk, level, optname, optval, optlen,
 929                         ip_setsockopt);
 930
 931         err = do_ip_setsockopt(sk, level, optname, optval, optlen);
 932 #ifdef CONFIG_NETFILTER
 933         /* we need to exclude all possible ENOPROTOOPTs except default case */
 934         if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
 935                         optname != IP_IPSEC_POLICY &&
 936                         optname != IP_XFRM_POLICY &&
 937                         !ip_mroute_opt(optname)) {
 938                 lock_sock(sk);
 939                 err = compat_nf_setsockopt(sk, PF_INET, optname,
 940                                            optval, optlen);
 941                 release_sock(sk);
 942         }
 943 #endif
 944         return err;
 945 }
 946
 947 EXPORT_SYMBOL(compat_ip_setsockopt);
 948 #endif
 949
 950 /*
 951  *      Get the options. Note for future reference. The GET of IP options gets the
 952  *      _received_ ones. The set sets the _sent_ ones.
 953  */
 954
 955 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
 956                             char __user *optval, int __user *optlen)
 957 {
 958         struct inet_sock *inet = inet_sk(sk);
 959         int val;
 960         int len;
 961
 962         if (level != SOL_IP)
 963                 return -EOPNOTSUPP;
 964
 965         if (ip_mroute_opt(optname))
 966                 return ip_mroute_getsockopt(sk,optname,optval,optlen);
 967
 968         if (get_user(len,optlen))
 969                 return -EFAULT;
 970         if (len < 0)
 971                 return -EINVAL;
 972
 973         lock_sock(sk);
 974
 975         switch (optname) {
 976         case IP_OPTIONS:
 977         {
 978                 unsigned char optbuf[sizeof(struct ip_options)+40];
 979                 struct ip_options * opt = (struct ip_options*)optbuf;
 980                 opt->optlen = 0;
 981                 if (inet->opt)
 982                         memcpy(optbuf, inet->opt,
 983                                sizeof(struct ip_options)+
 984                                inet->opt->optlen);
 985                 release_sock(sk);
 986
 987                 if (opt->optlen == 0)
 988                         return put_user(0, optlen);
 989
 990                 ip_options_undo(opt);
 991
 992                 len = min_t(unsigned int, len, opt->optlen);
 993                 if (put_user(len, optlen))
 994                         return -EFAULT;
 995                 if (copy_to_user(optval, opt->__data, len))
 996                         return -EFAULT;
 997                 return 0;
 998         }
 999         case IP_PKTINFO:
1000                 val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1001                 break;
1002         case IP_RECVTTL:
1003                 val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1004                 break;
1005         case IP_RECVTOS:
1006                 val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1007                 break;
1008         case IP_RECVOPTS:
1009                 val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1010                 break;
1011         case IP_RETOPTS:
1012                 val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1013                 break;
1014         case IP_PASSSEC:
1015                 val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1016                 break;
1017         case IP_TOS:
1018                 val = inet->tos;
1019                 break;
1020         case IP_TTL:
1021                 val = (inet->uc_ttl == -1 ?
1022                        sysctl_ip_default_ttl :
1023                        inet->uc_ttl);
1024                 break;
1025         case IP_HDRINCL:
1026                 val = inet->hdrincl;
1027                 break;
1028         case IP_MTU_DISCOVER:
1029                 val = inet->pmtudisc;
1030                 break;
1031         case IP_MTU:
1032         {
1033                 struct dst_entry *dst;
1034                 val = 0;
1035                 dst = sk_dst_get(sk);
1036                 if (dst) {
1037                         val = dst_mtu(dst);
1038                         dst_release(dst);
1039                 }
1040                 if (!val) {
1041                         release_sock(sk);
1042                         return -ENOTCONN;
1043                 }
1044                 break;
1045         }
1046         case IP_RECVERR:
1047                 val = inet->recverr;
1048                 break;
1049         case IP_MULTICAST_TTL:
1050                 val = inet->mc_ttl;
1051                 break;
1052         case IP_MULTICAST_LOOP:
1053                 val = inet->mc_loop;
1054                 break;
1055         case IP_MULTICAST_IF:
1056         {
1057                 struct in_addr addr;
1058                 len = min_t(unsigned int, len, sizeof(struct in_addr));
1059                 addr.s_addr = inet->mc_addr;
1060                 release_sock(sk);
1061
1062                 if (put_user(len, optlen))
1063                         return -EFAULT;
1064                 if (copy_to_user(optval, &addr, len))
1065                         return -EFAULT;
1066                 return 0;
1067         }
1068         case IP_MSFILTER:
1069         {
1070                 struct ip_msfilter msf;
1071                 int err;
1072
1073                 if (len < IP_MSFILTER_SIZE(0)) {
1074                         release_sock(sk);
1075                         return -EINVAL;
1076                 }
1077                 if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1078                         release_sock(sk);
1079                         return -EFAULT;
1080                 }
1081                 err = ip_mc_msfget(sk, &msf,
1082                                    (struct ip_msfilter __user *)optval, optlen);
1083                 release_sock(sk);
1084                 return err;
1085         }
1086         case MCAST_MSFILTER:
1087         {
1088                 struct group_filter gsf;
1089                 int err;
1090
1091                 if (len < GROUP_FILTER_SIZE(0)) {
1092                         release_sock(sk);
1093                         return -EINVAL;
1094                 }
1095                 if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1096                         release_sock(sk);
1097                         return -EFAULT;
1098                 }
1099                 err = ip_mc_gsfget(sk, &gsf,
1100                                    (struct group_filter __user *)optval, optlen);
1101                 release_sock(sk);
1102                 return err;
1103         }
1104         case IP_PKTOPTIONS:
1105         {
1106                 struct msghdr msg;
1107
1108                 release_sock(sk);
1109
1110                 if (sk->sk_type != SOCK_STREAM)
1111                         return -ENOPROTOOPT;
1112
1113                 msg.msg_control = optval;
1114                 msg.msg_controllen = len;
1115                 msg.msg_flags = 0;
1116
1117                 if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1118                         struct in_pktinfo info;
1119
1120                         info.ipi_addr.s_addr = inet->rcv_saddr;
1121                         info.ipi_spec_dst.s_addr = inet->rcv_saddr;
1122                         info.ipi_ifindex = inet->mc_index;
1123                         put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1124                 }
1125                 if (inet->cmsg_flags & IP_CMSG_TTL) {
1126                         int hlim = inet->mc_ttl;
1127                         put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1128                 }
1129                 len -= msg.msg_controllen;
1130                 return put_user(len, optlen);
1131         }
1132         case IP_FREEBIND:
1133                 val = inet->freebind;
1134                 break;
1135         default:
1136                 release_sock(sk);
1137                 return -ENOPROTOOPT;
1138         }
1139         release_sock(sk);
1140
1141         if (len < sizeof(int) && len > 0 && val>=0 && val<=255) {
1142                 unsigned char ucval = (unsigned char)val;
1143                 len = 1;
1144                 if (put_user(len, optlen))
1145                         return -EFAULT;
1146                 if (copy_to_user(optval,&ucval,1))
1147                         return -EFAULT;
1148         } else {
1149                 len = min_t(unsigned int, sizeof(int), len);
1150                 if (put_user(len, optlen))
1151                         return -EFAULT;
1152                 if (copy_to_user(optval,&val,len))
1153                         return -EFAULT;
1154         }
1155         return 0;
1156 }
1157
1158 int ip_getsockopt(struct sock *sk, int level,
1159                   int optname, char __user *optval, int __user *optlen)
1160 {
1161         int err;
1162
1163         err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1164 #ifdef CONFIG_NETFILTER
1165         /* we need to exclude all possible ENOPROTOOPTs except default case */
1166         if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1167                         !ip_mroute_opt(optname)) {
1168                 int len;
1169
1170                 if (get_user(len,optlen))
1171                         return -EFAULT;
1172
1173                 lock_sock(sk);
1174                 err = nf_getsockopt(sk, PF_INET, optname, optval,
1175                                 &len);
1176                 release_sock(sk);
1177                 if (err >= 0)
1178                         err = put_user(len, optlen);
1179                 return err;
1180         }
1181 #endif
1182         return err;
1183 }
1184
1185 #ifdef CONFIG_COMPAT
1186 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1187                          char __user *optval, int __user *optlen)
1188 {
1189         int err;
1190
1191         if (optname == MCAST_MSFILTER)
1192                 return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1193                         ip_getsockopt);
1194
1195         err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1196
1197 #ifdef CONFIG_NETFILTER
1198         /* we need to exclude all possible ENOPROTOOPTs except default case */
1199         if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1200                         !ip_mroute_opt(optname)) {
1201                 int len;
1202
1203                 if (get_user(len, optlen))
1204                         return -EFAULT;
1205
1206                 lock_sock(sk);
1207                 err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1208                 release_sock(sk);
1209                 if (err >= 0)
1210                         err = put_user(len, optlen);
1211                 return err;
1212         }
1213 #endif
1214         return err;
1215 }
1216
1217 EXPORT_SYMBOL(compat_ip_getsockopt);
1218 #endif
1219
1220 EXPORT_SYMBOL(ip_cmsg_recv);
1221
1222 EXPORT_SYMBOL(ip_getsockopt);
1223 EXPORT_SYMBOL(ip_setsockopt);