linux/net/ipv4/ip_sockglue.c
<<
>>
Prefs
   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 * Authors:     see ip.c
   9 *
  10 * Fixes:
  11 *              Many            :       Split from ip.c , see ip.c for history.
  12 *              Martin Mares    :       TOS setting fixed.
  13 *              Alan Cox        :       Fixed a couple of oopses in Martin's
  14 *                                      TOS tweaks.
  15 *              Mike McLagan    :       Routing by source
  16 */
  17
  18#include <linux/module.h>
  19#include <linux/types.h>
  20#include <linux/mm.h>
  21#include <linux/skbuff.h>
  22#include <linux/ip.h>
  23#include <linux/icmp.h>
  24#include <linux/inetdevice.h>
  25#include <linux/netdevice.h>
  26#include <linux/slab.h>
  27#include <net/sock.h>
  28#include <net/ip.h>
  29#include <net/icmp.h>
  30#include <net/tcp_states.h>
  31#include <linux/udp.h>
  32#include <linux/igmp.h>
  33#include <linux/netfilter.h>
  34#include <linux/route.h>
  35#include <linux/mroute.h>
  36#include <net/inet_ecn.h>
  37#include <net/route.h>
  38#include <net/xfrm.h>
  39#include <net/compat.h>
  40#if IS_ENABLED(CONFIG_IPV6)
  41#include <net/transp_v6.h>
  42#endif
  43#include <net/ip_fib.h>
  44
  45#include <linux/errqueue.h>
  46#include <asm/uaccess.h>
  47
  48#define IP_CMSG_PKTINFO         1
  49#define IP_CMSG_TTL             2
  50#define IP_CMSG_TOS             4
  51#define IP_CMSG_RECVOPTS        8
  52#define IP_CMSG_RETOPTS         16
  53#define IP_CMSG_PASSSEC         32
  54#define IP_CMSG_ORIGDSTADDR     64
  55
  56/*
  57 *      SOL_IP control messages.
  58 */
  59#define PKTINFO_SKB_CB(__skb) ((struct in_pktinfo *)((__skb)->cb))
  60
  61static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
  62{
  63        struct in_pktinfo info = *PKTINFO_SKB_CB(skb);
  64
  65        info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
  66
  67        put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
  68}
  69
  70static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
  71{
  72        int ttl = ip_hdr(skb)->ttl;
  73        put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
  74}
  75
  76static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
  77{
  78        put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
  79}
  80
  81static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
  82{
  83        if (IPCB(skb)->opt.optlen == 0)
  84                return;
  85
  86        put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
  87                 ip_hdr(skb) + 1);
  88}
  89
  90
  91static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
  92{
  93        unsigned char optbuf[sizeof(struct ip_options) + 40];
  94        struct ip_options *opt = (struct ip_options *)optbuf;
  95
  96        if (IPCB(skb)->opt.optlen == 0)
  97                return;
  98
  99        if (ip_options_echo(opt, skb)) {
 100                msg->msg_flags |= MSG_CTRUNC;
 101                return;
 102        }
 103        ip_options_undo(opt);
 104
 105        put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
 106}
 107
 108static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 109{
 110        char *secdata;
 111        u32 seclen, secid;
 112        int err;
 113
 114        err = security_socket_getpeersec_dgram(NULL, skb, &secid);
 115        if (err)
 116                return;
 117
 118        err = security_secid_to_secctx(secid, &secdata, &seclen);
 119        if (err)
 120                return;
 121
 122        put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
 123        security_release_secctx(secdata, seclen);
 124}
 125
 126static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
 127{
 128        struct sockaddr_in sin;
 129        const struct iphdr *iph = ip_hdr(skb);
 130        __be16 *ports = (__be16 *)skb_transport_header(skb);
 131
 132        if (skb_transport_offset(skb) + 4 > skb->len)
 133                return;
 134
 135        /* All current transport protocols have the port numbers in the
 136         * first four bytes of the transport header and this function is
 137         * written with this assumption in mind.
 138         */
 139
 140        sin.sin_family = AF_INET;
 141        sin.sin_addr.s_addr = iph->daddr;
 142        sin.sin_port = ports[1];
 143        memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
 144
 145        put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
 146}
 147
 148void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
 149{
 150        struct inet_sock *inet = inet_sk(skb->sk);
 151        unsigned int flags = inet->cmsg_flags;
 152
 153        /* Ordered by supposed usage frequency */
 154        if (flags & 1)
 155                ip_cmsg_recv_pktinfo(msg, skb);
 156        if ((flags >>= 1) == 0)
 157                return;
 158
 159        if (flags & 1)
 160                ip_cmsg_recv_ttl(msg, skb);
 161        if ((flags >>= 1) == 0)
 162                return;
 163
 164        if (flags & 1)
 165                ip_cmsg_recv_tos(msg, skb);
 166        if ((flags >>= 1) == 0)
 167                return;
 168
 169        if (flags & 1)
 170                ip_cmsg_recv_opts(msg, skb);
 171        if ((flags >>= 1) == 0)
 172                return;
 173
 174        if (flags & 1)
 175                ip_cmsg_recv_retopts(msg, skb);
 176        if ((flags >>= 1) == 0)
 177                return;
 178
 179        if (flags & 1)
 180                ip_cmsg_recv_security(msg, skb);
 181
 182        if ((flags >>= 1) == 0)
 183                return;
 184        if (flags & 1)
 185                ip_cmsg_recv_dstaddr(msg, skb);
 186
 187}
 188EXPORT_SYMBOL(ip_cmsg_recv);
 189
 190int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc)
 191{
 192        int err;
 193        struct cmsghdr *cmsg;
 194
 195        for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 196                if (!CMSG_OK(msg, cmsg))
 197                        return -EINVAL;
 198                if (cmsg->cmsg_level != SOL_IP)
 199                        continue;
 200                switch (cmsg->cmsg_type) {
 201                case IP_RETOPTS:
 202                        err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
 203                        err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg),
 204                                             err < 40 ? err : 40);
 205                        if (err)
 206                                return err;
 207                        break;
 208                case IP_PKTINFO:
 209                {
 210                        struct in_pktinfo *info;
 211                        if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
 212                                return -EINVAL;
 213                        info = (struct in_pktinfo *)CMSG_DATA(cmsg);
 214                        ipc->oif = info->ipi_ifindex;
 215                        ipc->addr = info->ipi_spec_dst.s_addr;
 216                        break;
 217                }
 218                default:
 219                        return -EINVAL;
 220                }
 221        }
 222        return 0;
 223}
 224
 225
 226/* Special input handler for packets caught by router alert option.
 227   They are selected only by protocol field, and then processed likely
 228   local ones; but only if someone wants them! Otherwise, router
 229   not running rsvpd will kill RSVP.
 230
 231   It is user level problem, what it will make with them.
 232   I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
 233   but receiver should be enough clever f.e. to forward mtrace requests,
 234   sent to multicast group to reach destination designated router.
 235 */
 236struct ip_ra_chain __rcu *ip_ra_chain;
 237static DEFINE_SPINLOCK(ip_ra_lock);
 238
 239
 240static void ip_ra_destroy_rcu(struct rcu_head *head)
 241{
 242        struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
 243
 244        sock_put(ra->saved_sk);
 245        kfree(ra);
 246}
 247
 248int ip_ra_control(struct sock *sk, unsigned char on,
 249                  void (*destructor)(struct sock *))
 250{
 251        struct ip_ra_chain *ra, *new_ra;
 252        struct ip_ra_chain __rcu **rap;
 253
 254        if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
 255                return -EINVAL;
 256
 257        new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
 258
 259        spin_lock_bh(&ip_ra_lock);
 260        for (rap = &ip_ra_chain;
 261             (ra = rcu_dereference_protected(*rap,
 262                        lockdep_is_held(&ip_ra_lock))) != NULL;
 263             rap = &ra->next) {
 264                if (ra->sk == sk) {
 265                        if (on) {
 266                                spin_unlock_bh(&ip_ra_lock);
 267                                kfree(new_ra);
 268                                return -EADDRINUSE;
 269                        }
 270                        /* dont let ip_call_ra_chain() use sk again */
 271                        ra->sk = NULL;
 272                        rcu_assign_pointer(*rap, ra->next);
 273                        spin_unlock_bh(&ip_ra_lock);
 274
 275                        if (ra->destructor)
 276                                ra->destructor(sk);
 277                        /*
 278                         * Delay sock_put(sk) and kfree(ra) after one rcu grace
 279                         * period. This guarantee ip_call_ra_chain() dont need
 280                         * to mess with socket refcounts.
 281                         */
 282                        ra->saved_sk = sk;
 283                        call_rcu(&ra->rcu, ip_ra_destroy_rcu);
 284                        return 0;
 285                }
 286        }
 287        if (new_ra == NULL) {
 288                spin_unlock_bh(&ip_ra_lock);
 289                return -ENOBUFS;
 290        }
 291        new_ra->sk = sk;
 292        new_ra->destructor = destructor;
 293
 294        new_ra->next = ra;
 295        rcu_assign_pointer(*rap, new_ra);
 296        sock_hold(sk);
 297        spin_unlock_bh(&ip_ra_lock);
 298
 299        return 0;
 300}
 301
 302void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 303                   __be16 port, u32 info, u8 *payload)
 304{
 305        struct sock_exterr_skb *serr;
 306
 307        skb = skb_clone(skb, GFP_ATOMIC);
 308        if (!skb)
 309                return;
 310
 311        serr = SKB_EXT_ERR(skb);
 312        serr->ee.ee_errno = err;
 313        serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
 314        serr->ee.ee_type = icmp_hdr(skb)->type;
 315        serr->ee.ee_code = icmp_hdr(skb)->code;
 316        serr->ee.ee_pad = 0;
 317        serr->ee.ee_info = info;
 318        serr->ee.ee_data = 0;
 319        serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
 320                                   skb_network_header(skb);
 321        serr->port = port;
 322
 323        if (skb_pull(skb, payload - skb->data) != NULL) {
 324                skb_reset_transport_header(skb);
 325                if (sock_queue_err_skb(sk, skb) == 0)
 326                        return;
 327        }
 328        kfree_skb(skb);
 329}
 330
 331void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
 332{
 333        struct inet_sock *inet = inet_sk(sk);
 334        struct sock_exterr_skb *serr;
 335        struct iphdr *iph;
 336        struct sk_buff *skb;
 337
 338        if (!inet->recverr)
 339                return;
 340
 341        skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
 342        if (!skb)
 343                return;
 344
 345        skb_put(skb, sizeof(struct iphdr));
 346        skb_reset_network_header(skb);
 347        iph = ip_hdr(skb);
 348        iph->daddr = daddr;
 349
 350        serr = SKB_EXT_ERR(skb);
 351        serr->ee.ee_errno = err;
 352        serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 353        serr->ee.ee_type = 0;
 354        serr->ee.ee_code = 0;
 355        serr->ee.ee_pad = 0;
 356        serr->ee.ee_info = info;
 357        serr->ee.ee_data = 0;
 358        serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 359        serr->port = port;
 360
 361        __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 362        skb_reset_transport_header(skb);
 363
 364        if (sock_queue_err_skb(sk, skb))
 365                kfree_skb(skb);
 366}
 367
 368/*
 369 *      Handle MSG_ERRQUEUE
 370 */
 371int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
 372{
 373        struct sock_exterr_skb *serr;
 374        struct sk_buff *skb, *skb2;
 375        struct sockaddr_in *sin;
 376        struct {
 377                struct sock_extended_err ee;
 378                struct sockaddr_in       offender;
 379        } errhdr;
 380        int err;
 381        int copied;
 382
 383        err = -EAGAIN;
 384        skb = skb_dequeue(&sk->sk_error_queue);
 385        if (skb == NULL)
 386                goto out;
 387
 388        copied = skb->len;
 389        if (copied > len) {
 390                msg->msg_flags |= MSG_TRUNC;
 391                copied = len;
 392        }
 393        err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 394        if (err)
 395                goto out_free_skb;
 396
 397        sock_recv_timestamp(msg, sk, skb);
 398
 399        serr = SKB_EXT_ERR(skb);
 400
 401        sin = (struct sockaddr_in *)msg->msg_name;
 402        if (sin) {
 403                sin->sin_family = AF_INET;
 404                sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
 405                                                   serr->addr_offset);
 406                sin->sin_port = serr->port;
 407                memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
 408        }
 409
 410        memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 411        sin = &errhdr.offender;
 412        sin->sin_family = AF_UNSPEC;
 413        if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
 414                struct inet_sock *inet = inet_sk(sk);
 415
 416                sin->sin_family = AF_INET;
 417                sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 418                sin->sin_port = 0;
 419                memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
 420                if (inet->cmsg_flags)
 421                        ip_cmsg_recv(msg, skb);
 422        }
 423
 424        put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
 425
 426        /* Now we could try to dump offended packet options */
 427
 428        msg->msg_flags |= MSG_ERRQUEUE;
 429        err = copied;
 430
 431        /* Reset and regenerate socket error */
 432        spin_lock_bh(&sk->sk_error_queue.lock);
 433        sk->sk_err = 0;
 434        skb2 = skb_peek(&sk->sk_error_queue);
 435        if (skb2 != NULL) {
 436                sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 437                spin_unlock_bh(&sk->sk_error_queue.lock);
 438                sk->sk_error_report(sk);
 439        } else
 440                spin_unlock_bh(&sk->sk_error_queue.lock);
 441
 442out_free_skb:
 443        kfree_skb(skb);
 444out:
 445        return err;
 446}
 447
 448
 449/*
 450 *      Socket option code for IP. This is the end of the line after any
 451 *      TCP,UDP etc options on an IP socket.
 452 */
 453
 454static int do_ip_setsockopt(struct sock *sk, int level,
 455                            int optname, char __user *optval, unsigned int optlen)
 456{
 457        struct inet_sock *inet = inet_sk(sk);
 458        int val = 0, err;
 459
 460        if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) |
 461                             (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) |
 462                             (1<<IP_RETOPTS) | (1<<IP_TOS) |
 463                             (1<<IP_TTL) | (1<<IP_HDRINCL) |
 464                             (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) |
 465                             (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND) |
 466                             (1<<IP_PASSSEC) | (1<<IP_TRANSPARENT) |
 467                             (1<<IP_MINTTL) | (1<<IP_NODEFRAG))) ||
 468            optname == IP_UNICAST_IF ||
 469            optname == IP_MULTICAST_TTL ||
 470            optname == IP_MULTICAST_ALL ||
 471            optname == IP_MULTICAST_LOOP ||
 472            optname == IP_RECVORIGDSTADDR) {
 473                if (optlen >= sizeof(int)) {
 474                        if (get_user(val, (int __user *) optval))
 475                                return -EFAULT;
 476                } else if (optlen >= sizeof(char)) {
 477                        unsigned char ucval;
 478
 479                        if (get_user(ucval, (unsigned char __user *) optval))
 480                                return -EFAULT;
 481                        val = (int) ucval;
 482                }
 483        }
 484
 485        /* If optlen==0, it is equivalent to val == 0 */
 486
 487        if (ip_mroute_opt(optname))
 488                return ip_mroute_setsockopt(sk, optname, optval, optlen);
 489
 490        err = 0;
 491        lock_sock(sk);
 492
 493        switch (optname) {
 494        case IP_OPTIONS:
 495        {
 496                struct ip_options_rcu *old, *opt = NULL;
 497
 498                if (optlen > 40)
 499                        goto e_inval;
 500                err = ip_options_get_from_user(sock_net(sk), &opt,
 501                                               optval, optlen);
 502                if (err)
 503                        break;
 504                old = rcu_dereference_protected(inet->inet_opt,
 505                                                sock_owned_by_user(sk));
 506                if (inet->is_icsk) {
 507                        struct inet_connection_sock *icsk = inet_csk(sk);
 508#if IS_ENABLED(CONFIG_IPV6)
 509                        if (sk->sk_family == PF_INET ||
 510                            (!((1 << sk->sk_state) &
 511                               (TCPF_LISTEN | TCPF_CLOSE)) &&
 512                             inet->inet_daddr != LOOPBACK4_IPV6)) {
 513#endif
 514                                if (old)
 515                                        icsk->icsk_ext_hdr_len -= old->opt.optlen;
 516                                if (opt)
 517                                        icsk->icsk_ext_hdr_len += opt->opt.optlen;
 518                                icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 519#if IS_ENABLED(CONFIG_IPV6)
 520                        }
 521#endif
 522                }
 523                rcu_assign_pointer(inet->inet_opt, opt);
 524                if (old)
 525                        kfree_rcu(old, rcu);
 526                break;
 527        }
 528        case IP_PKTINFO:
 529                if (val)
 530                        inet->cmsg_flags |= IP_CMSG_PKTINFO;
 531                else
 532                        inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
 533                break;
 534        case IP_RECVTTL:
 535                if (val)
 536                        inet->cmsg_flags |=  IP_CMSG_TTL;
 537                else
 538                        inet->cmsg_flags &= ~IP_CMSG_TTL;
 539                break;
 540        case IP_RECVTOS:
 541                if (val)
 542                        inet->cmsg_flags |=  IP_CMSG_TOS;
 543                else
 544                        inet->cmsg_flags &= ~IP_CMSG_TOS;
 545                break;
 546        case IP_RECVOPTS:
 547                if (val)
 548                        inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
 549                else
 550                        inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
 551                break;
 552        case IP_RETOPTS:
 553                if (val)
 554                        inet->cmsg_flags |= IP_CMSG_RETOPTS;
 555                else
 556                        inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
 557                break;
 558        case IP_PASSSEC:
 559                if (val)
 560                        inet->cmsg_flags |= IP_CMSG_PASSSEC;
 561                else
 562                        inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
 563                break;
 564        case IP_RECVORIGDSTADDR:
 565                if (val)
 566                        inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR;
 567                else
 568                        inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR;
 569                break;
 570        case IP_TOS:    /* This sets both TOS and Precedence */
 571                if (sk->sk_type == SOCK_STREAM) {
 572                        val &= ~INET_ECN_MASK;
 573                        val |= inet->tos & INET_ECN_MASK;
 574                }
 575                if (inet->tos != val) {
 576                        inet->tos = val;
 577                        sk->sk_priority = rt_tos2priority(val);
 578                        sk_dst_reset(sk);
 579                }
 580                break;
 581        case IP_TTL:
 582                if (optlen < 1)
 583                        goto e_inval;
 584                if (val != -1 && (val < 0 || val > 255))
 585                        goto e_inval;
 586                inet->uc_ttl = val;
 587                break;
 588        case IP_HDRINCL:
 589                if (sk->sk_type != SOCK_RAW) {
 590                        err = -ENOPROTOOPT;
 591                        break;
 592                }
 593                inet->hdrincl = val ? 1 : 0;
 594                break;
 595        case IP_NODEFRAG:
 596                if (sk->sk_type != SOCK_RAW) {
 597                        err = -ENOPROTOOPT;
 598                        break;
 599                }
 600                inet->nodefrag = val ? 1 : 0;
 601                break;
 602        case IP_MTU_DISCOVER:
 603                if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_PROBE)
 604                        goto e_inval;
 605                inet->pmtudisc = val;
 606                break;
 607        case IP_RECVERR:
 608                inet->recverr = !!val;
 609                if (!val)
 610                        skb_queue_purge(&sk->sk_error_queue);
 611                break;
 612        case IP_MULTICAST_TTL:
 613                if (sk->sk_type == SOCK_STREAM)
 614                        goto e_inval;
 615                if (optlen < 1)
 616                        goto e_inval;
 617                if (val == -1)
 618                        val = 1;
 619                if (val < 0 || val > 255)
 620                        goto e_inval;
 621                inet->mc_ttl = val;
 622                break;
 623        case IP_MULTICAST_LOOP:
 624                if (optlen < 1)
 625                        goto e_inval;
 626                inet->mc_loop = !!val;
 627                break;
 628        case IP_UNICAST_IF:
 629        {
 630                struct net_device *dev = NULL;
 631                int ifindex;
 632
 633                if (optlen != sizeof(int))
 634                        goto e_inval;
 635
 636                ifindex = (__force int)ntohl((__force __be32)val);
 637                if (ifindex == 0) {
 638                        inet->uc_index = 0;
 639                        err = 0;
 640                        break;
 641                }
 642
 643                dev = dev_get_by_index(sock_net(sk), ifindex);
 644                err = -EADDRNOTAVAIL;
 645                if (!dev)
 646                        break;
 647                dev_put(dev);
 648
 649                err = -EINVAL;
 650                if (sk->sk_bound_dev_if)
 651                        break;
 652
 653                inet->uc_index = ifindex;
 654                err = 0;
 655                break;
 656        }
 657        case IP_MULTICAST_IF:
 658        {
 659                struct ip_mreqn mreq;
 660                struct net_device *dev = NULL;
 661
 662                if (sk->sk_type == SOCK_STREAM)
 663                        goto e_inval;
 664                /*
 665                 *      Check the arguments are allowable
 666                 */
 667
 668                if (optlen < sizeof(struct in_addr))
 669                        goto e_inval;
 670
 671                err = -EFAULT;
 672                if (optlen >= sizeof(struct ip_mreqn)) {
 673                        if (copy_from_user(&mreq, optval, sizeof(mreq)))
 674                                break;
 675                } else {
 676                        memset(&mreq, 0, sizeof(mreq));
 677                        if (optlen >= sizeof(struct ip_mreq)) {
 678                                if (copy_from_user(&mreq, optval,
 679                                                   sizeof(struct ip_mreq)))
 680                                        break;
 681                        } else if (optlen >= sizeof(struct in_addr)) {
 682                                if (copy_from_user(&mreq.imr_address, optval,
 683                                                   sizeof(struct in_addr)))
 684                                        break;
 685                        }
 686                }
 687
 688                if (!mreq.imr_ifindex) {
 689                        if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
 690                                inet->mc_index = 0;
 691                                inet->mc_addr  = 0;
 692                                err = 0;
 693                                break;
 694                        }
 695                        dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
 696                        if (dev)
 697                                mreq.imr_ifindex = dev->ifindex;
 698                } else
 699                        dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
 700
 701
 702                err = -EADDRNOTAVAIL;
 703                if (!dev)
 704                        break;
 705                dev_put(dev);
 706
 707                err = -EINVAL;
 708                if (sk->sk_bound_dev_if &&
 709                    mreq.imr_ifindex != sk->sk_bound_dev_if)
 710                        break;
 711
 712                inet->mc_index = mreq.imr_ifindex;
 713                inet->mc_addr  = mreq.imr_address.s_addr;
 714                err = 0;
 715                break;
 716        }
 717
 718        case IP_ADD_MEMBERSHIP:
 719        case IP_DROP_MEMBERSHIP:
 720        {
 721                struct ip_mreqn mreq;
 722
 723                err = -EPROTO;
 724                if (inet_sk(sk)->is_icsk)
 725                        break;
 726
 727                if (optlen < sizeof(struct ip_mreq))
 728                        goto e_inval;
 729                err = -EFAULT;
 730                if (optlen >= sizeof(struct ip_mreqn)) {
 731                        if (copy_from_user(&mreq, optval, sizeof(mreq)))
 732                                break;
 733                } else {
 734                        memset(&mreq, 0, sizeof(mreq));
 735                        if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq)))
 736                                break;
 737                }
 738
 739                if (optname == IP_ADD_MEMBERSHIP)
 740                        err = ip_mc_join_group(sk, &mreq);
 741                else
 742                        err = ip_mc_leave_group(sk, &mreq);
 743                break;
 744        }
 745        case IP_MSFILTER:
 746        {
 747                struct ip_msfilter *msf;
 748
 749                if (optlen < IP_MSFILTER_SIZE(0))
 750                        goto e_inval;
 751                if (optlen > sysctl_optmem_max) {
 752                        err = -ENOBUFS;
 753                        break;
 754                }
 755                msf = kmalloc(optlen, GFP_KERNEL);
 756                if (!msf) {
 757                        err = -ENOBUFS;
 758                        break;
 759                }
 760                err = -EFAULT;
 761                if (copy_from_user(msf, optval, optlen)) {
 762                        kfree(msf);
 763                        break;
 764                }
 765                /* numsrc >= (1G-4) overflow in 32 bits */
 766                if (msf->imsf_numsrc >= 0x3ffffffcU ||
 767                    msf->imsf_numsrc > sysctl_igmp_max_msf) {
 768                        kfree(msf);
 769                        err = -ENOBUFS;
 770                        break;
 771                }
 772                if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
 773                        kfree(msf);
 774                        err = -EINVAL;
 775                        break;
 776                }
 777                err = ip_mc_msfilter(sk, msf, 0);
 778                kfree(msf);
 779                break;
 780        }
 781        case IP_BLOCK_SOURCE:
 782        case IP_UNBLOCK_SOURCE:
 783        case IP_ADD_SOURCE_MEMBERSHIP:
 784        case IP_DROP_SOURCE_MEMBERSHIP:
 785        {
 786                struct ip_mreq_source mreqs;
 787                int omode, add;
 788
 789                if (optlen != sizeof(struct ip_mreq_source))
 790                        goto e_inval;
 791                if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
 792                        err = -EFAULT;
 793                        break;
 794                }
 795                if (optname == IP_BLOCK_SOURCE) {
 796                        omode = MCAST_EXCLUDE;
 797                        add = 1;
 798                } else if (optname == IP_UNBLOCK_SOURCE) {
 799                        omode = MCAST_EXCLUDE;
 800                        add = 0;
 801                } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
 802                        struct ip_mreqn mreq;
 803
 804                        mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
 805                        mreq.imr_address.s_addr = mreqs.imr_interface;
 806                        mreq.imr_ifindex = 0;
 807                        err = ip_mc_join_group(sk, &mreq);
 808                        if (err && err != -EADDRINUSE)
 809                                break;
 810                        omode = MCAST_INCLUDE;
 811                        add = 1;
 812                } else /* IP_DROP_SOURCE_MEMBERSHIP */ {
 813                        omode = MCAST_INCLUDE;
 814                        add = 0;
 815                }
 816                err = ip_mc_source(add, omode, sk, &mreqs, 0);
 817                break;
 818        }
 819        case MCAST_JOIN_GROUP:
 820        case MCAST_LEAVE_GROUP:
 821        {
 822                struct group_req greq;
 823                struct sockaddr_in *psin;
 824                struct ip_mreqn mreq;
 825
 826                if (optlen < sizeof(struct group_req))
 827                        goto e_inval;
 828                err = -EFAULT;
 829                if (copy_from_user(&greq, optval, sizeof(greq)))
 830                        break;
 831                psin = (struct sockaddr_in *)&greq.gr_group;
 832                if (psin->sin_family != AF_INET)
 833                        goto e_inval;
 834                memset(&mreq, 0, sizeof(mreq));
 835                mreq.imr_multiaddr = psin->sin_addr;
 836                mreq.imr_ifindex = greq.gr_interface;
 837
 838                if (optname == MCAST_JOIN_GROUP)
 839                        err = ip_mc_join_group(sk, &mreq);
 840                else
 841                        err = ip_mc_leave_group(sk, &mreq);
 842                break;
 843        }
 844        case MCAST_JOIN_SOURCE_GROUP:
 845        case MCAST_LEAVE_SOURCE_GROUP:
 846        case MCAST_BLOCK_SOURCE:
 847        case MCAST_UNBLOCK_SOURCE:
 848        {
 849                struct group_source_req greqs;
 850                struct ip_mreq_source mreqs;
 851                struct sockaddr_in *psin;
 852                int omode, add;
 853
 854                if (optlen != sizeof(struct group_source_req))
 855                        goto e_inval;
 856                if (copy_from_user(&greqs, optval, sizeof(greqs))) {
 857                        err = -EFAULT;
 858                        break;
 859                }
 860                if (greqs.gsr_group.ss_family != AF_INET ||
 861                    greqs.gsr_source.ss_family != AF_INET) {
 862                        err = -EADDRNOTAVAIL;
 863                        break;
 864                }
 865                psin = (struct sockaddr_in *)&greqs.gsr_group;
 866                mreqs.imr_multiaddr = psin->sin_addr.s_addr;
 867                psin = (struct sockaddr_in *)&greqs.gsr_source;
 868                mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
 869                mreqs.imr_interface = 0; /* use index for mc_source */
 870
 871                if (optname == MCAST_BLOCK_SOURCE) {
 872                        omode = MCAST_EXCLUDE;
 873                        add = 1;
 874                } else if (optname == MCAST_UNBLOCK_SOURCE) {
 875                        omode = MCAST_EXCLUDE;
 876                        add = 0;
 877                } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
 878                        struct ip_mreqn mreq;
 879
 880                        psin = (struct sockaddr_in *)&greqs.gsr_group;
 881                        mreq.imr_multiaddr = psin->sin_addr;
 882                        mreq.imr_address.s_addr = 0;
 883                        mreq.imr_ifindex = greqs.gsr_interface;
 884                        err = ip_mc_join_group(sk, &mreq);
 885                        if (err && err != -EADDRINUSE)
 886                                break;
 887                        greqs.gsr_interface = mreq.imr_ifindex;
 888                        omode = MCAST_INCLUDE;
 889                        add = 1;
 890                } else /* MCAST_LEAVE_SOURCE_GROUP */ {
 891                        omode = MCAST_INCLUDE;
 892                        add = 0;
 893                }
 894                err = ip_mc_source(add, omode, sk, &mreqs,
 895                                   greqs.gsr_interface);
 896                break;
 897        }
 898        case MCAST_MSFILTER:
 899        {
 900                struct sockaddr_in *psin;
 901                struct ip_msfilter *msf = NULL;
 902                struct group_filter *gsf = NULL;
 903                int msize, i, ifindex;
 904
 905                if (optlen < GROUP_FILTER_SIZE(0))
 906                        goto e_inval;
 907                if (optlen > sysctl_optmem_max) {
 908                        err = -ENOBUFS;
 909                        break;
 910                }
 911                gsf = kmalloc(optlen, GFP_KERNEL);
 912                if (!gsf) {
 913                        err = -ENOBUFS;
 914                        break;
 915                }
 916                err = -EFAULT;
 917                if (copy_from_user(gsf, optval, optlen))
 918                        goto mc_msf_out;
 919
 920                /* numsrc >= (4G-140)/128 overflow in 32 bits */
 921                if (gsf->gf_numsrc >= 0x1ffffff ||
 922                    gsf->gf_numsrc > sysctl_igmp_max_msf) {
 923                        err = -ENOBUFS;
 924                        goto mc_msf_out;
 925                }
 926                if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
 927                        err = -EINVAL;
 928                        goto mc_msf_out;
 929                }
 930                msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
 931                msf = kmalloc(msize, GFP_KERNEL);
 932                if (!msf) {
 933                        err = -ENOBUFS;
 934                        goto mc_msf_out;
 935                }
 936                ifindex = gsf->gf_interface;
 937                psin = (struct sockaddr_in *)&gsf->gf_group;
 938                if (psin->sin_family != AF_INET) {
 939                        err = -EADDRNOTAVAIL;
 940                        goto mc_msf_out;
 941                }
 942                msf->imsf_multiaddr = psin->sin_addr.s_addr;
 943                msf->imsf_interface = 0;
 944                msf->imsf_fmode = gsf->gf_fmode;
 945                msf->imsf_numsrc = gsf->gf_numsrc;
 946                err = -EADDRNOTAVAIL;
 947                for (i = 0; i < gsf->gf_numsrc; ++i) {
 948                        psin = (struct sockaddr_in *)&gsf->gf_slist[i];
 949
 950                        if (psin->sin_family != AF_INET)
 951                                goto mc_msf_out;
 952                        msf->imsf_slist[i] = psin->sin_addr.s_addr;
 953                }
 954                kfree(gsf);
 955                gsf = NULL;
 956
 957                err = ip_mc_msfilter(sk, msf, ifindex);
 958mc_msf_out:
 959                kfree(msf);
 960                kfree(gsf);
 961                break;
 962        }
 963        case IP_MULTICAST_ALL:
 964                if (optlen < 1)
 965                        goto e_inval;
 966                if (val != 0 && val != 1)
 967                        goto e_inval;
 968                inet->mc_all = val;
 969                break;
 970        case IP_ROUTER_ALERT:
 971                err = ip_ra_control(sk, val ? 1 : 0, NULL);
 972                break;
 973
 974        case IP_FREEBIND:
 975                if (optlen < 1)
 976                        goto e_inval;
 977                inet->freebind = !!val;
 978                break;
 979
 980        case IP_IPSEC_POLICY:
 981        case IP_XFRM_POLICY:
 982                err = -EPERM;
 983                if (!capable(CAP_NET_ADMIN))
 984                        break;
 985                err = xfrm_user_policy(sk, optname, optval, optlen);
 986                break;
 987
 988        case IP_TRANSPARENT:
 989                if (!!val && !capable(CAP_NET_RAW) && !capable(CAP_NET_ADMIN)) {
 990                        err = -EPERM;
 991                        break;
 992                }
 993                if (optlen < 1)
 994                        goto e_inval;
 995                inet->transparent = !!val;
 996                break;
 997
 998        case IP_MINTTL:
 999                if (optlen < 1)
1000                        goto e_inval;
1001                if (val < 0 || val > 255)
1002                        goto e_inval;
1003                inet->min_ttl = val;
1004                break;
1005
1006        default:
1007                err = -ENOPROTOOPT;
1008                break;
1009        }
1010        release_sock(sk);
1011        return err;
1012
1013e_inval:
1014        release_sock(sk);
1015        return -EINVAL;
1016}
1017
1018/**
1019 * ipv4_pktinfo_prepare - transfert some info from rtable to skb
1020 * @sk: socket
1021 * @skb: buffer
1022 *
1023 * To support IP_CMSG_PKTINFO option, we store rt_iif and specific
1024 * destination in skb->cb[] before dst drop.
1025 * This way, receiver doesnt make cache line misses to read rtable.
1026 */
1027void ipv4_pktinfo_prepare(struct sk_buff *skb)
1028{
1029        struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);
1030
1031        if (skb_rtable(skb)) {
1032                pktinfo->ipi_ifindex = inet_iif(skb);
1033                pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
1034        } else {
1035                pktinfo->ipi_ifindex = 0;
1036                pktinfo->ipi_spec_dst.s_addr = 0;
1037        }
1038        skb_dst_drop(skb);
1039}
1040
1041int ip_setsockopt(struct sock *sk, int level,
1042                int optname, char __user *optval, unsigned int optlen)
1043{
1044        int err;
1045
1046        if (level != SOL_IP)
1047                return -ENOPROTOOPT;
1048
1049        err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1050#ifdef CONFIG_NETFILTER
1051        /* we need to exclude all possible ENOPROTOOPTs except default case */
1052        if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1053                        optname != IP_IPSEC_POLICY &&
1054                        optname != IP_XFRM_POLICY &&
1055                        !ip_mroute_opt(optname)) {
1056                lock_sock(sk);
1057                err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1058                release_sock(sk);
1059        }
1060#endif
1061        return err;
1062}
1063EXPORT_SYMBOL(ip_setsockopt);
1064
1065#ifdef CONFIG_COMPAT
1066int compat_ip_setsockopt(struct sock *sk, int level, int optname,
1067                         char __user *optval, unsigned int optlen)
1068{
1069        int err;
1070
1071        if (level != SOL_IP)
1072                return -ENOPROTOOPT;
1073
1074        if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
1075                return compat_mc_setsockopt(sk, level, optname, optval, optlen,
1076                        ip_setsockopt);
1077
1078        err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1079#ifdef CONFIG_NETFILTER
1080        /* we need to exclude all possible ENOPROTOOPTs except default case */
1081        if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1082                        optname != IP_IPSEC_POLICY &&
1083                        optname != IP_XFRM_POLICY &&
1084                        !ip_mroute_opt(optname)) {
1085                lock_sock(sk);
1086                err = compat_nf_setsockopt(sk, PF_INET, optname,
1087                                           optval, optlen);
1088                release_sock(sk);
1089        }
1090#endif
1091        return err;
1092}
1093EXPORT_SYMBOL(compat_ip_setsockopt);
1094#endif
1095
1096/*
1097 *      Get the options. Note for future reference. The GET of IP options gets
1098 *      the _received_ ones. The set sets the _sent_ ones.
1099 */
1100
1101static int do_ip_getsockopt(struct sock *sk, int level, int optname,
1102                            char __user *optval, int __user *optlen, unsigned int flags)
1103{
1104        struct inet_sock *inet = inet_sk(sk);
1105        int val;
1106        int len;
1107
1108        if (level != SOL_IP)
1109                return -EOPNOTSUPP;
1110
1111        if (ip_mroute_opt(optname))
1112                return ip_mroute_getsockopt(sk, optname, optval, optlen);
1113
1114        if (get_user(len, optlen))
1115                return -EFAULT;
1116        if (len < 0)
1117                return -EINVAL;
1118
1119        lock_sock(sk);
1120
1121        switch (optname) {
1122        case IP_OPTIONS:
1123        {
1124                unsigned char optbuf[sizeof(struct ip_options)+40];
1125                struct ip_options *opt = (struct ip_options *)optbuf;
1126                struct ip_options_rcu *inet_opt;
1127
1128                inet_opt = rcu_dereference_protected(inet->inet_opt,
1129                                                     sock_owned_by_user(sk));
1130                opt->optlen = 0;
1131                if (inet_opt)
1132                        memcpy(optbuf, &inet_opt->opt,
1133                               sizeof(struct ip_options) +
1134                               inet_opt->opt.optlen);
1135                release_sock(sk);
1136
1137                if (opt->optlen == 0)
1138                        return put_user(0, optlen);
1139
1140                ip_options_undo(opt);
1141
1142                len = min_t(unsigned int, len, opt->optlen);
1143                if (put_user(len, optlen))
1144                        return -EFAULT;
1145                if (copy_to_user(optval, opt->__data, len))
1146                        return -EFAULT;
1147                return 0;
1148        }
1149        case IP_PKTINFO:
1150                val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1151                break;
1152        case IP_RECVTTL:
1153                val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1154                break;
1155        case IP_RECVTOS:
1156                val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1157                break;
1158        case IP_RECVOPTS:
1159                val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1160                break;
1161        case IP_RETOPTS:
1162                val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1163                break;
1164        case IP_PASSSEC:
1165                val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1166                break;
1167        case IP_RECVORIGDSTADDR:
1168                val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0;
1169                break;
1170        case IP_TOS:
1171                val = inet->tos;
1172                break;
1173        case IP_TTL:
1174                val = (inet->uc_ttl == -1 ?
1175                       sysctl_ip_default_ttl :
1176                       inet->uc_ttl);
1177                break;
1178        case IP_HDRINCL:
1179                val = inet->hdrincl;
1180                break;
1181        case IP_NODEFRAG:
1182                val = inet->nodefrag;
1183                break;
1184        case IP_MTU_DISCOVER:
1185                val = inet->pmtudisc;
1186                break;
1187        case IP_MTU:
1188        {
1189                struct dst_entry *dst;
1190                val = 0;
1191                dst = sk_dst_get(sk);
1192                if (dst) {
1193                        val = dst_mtu(dst);
1194                        dst_release(dst);
1195                }
1196                if (!val) {
1197                        release_sock(sk);
1198                        return -ENOTCONN;
1199                }
1200                break;
1201        }
1202        case IP_RECVERR:
1203                val = inet->recverr;
1204                break;
1205        case IP_MULTICAST_TTL:
1206                val = inet->mc_ttl;
1207                break;
1208        case IP_MULTICAST_LOOP:
1209                val = inet->mc_loop;
1210                break;
1211        case IP_UNICAST_IF:
1212                val = (__force int)htonl((__u32) inet->uc_index);
1213                break;
1214        case IP_MULTICAST_IF:
1215        {
1216                struct in_addr addr;
1217                len = min_t(unsigned int, len, sizeof(struct in_addr));
1218                addr.s_addr = inet->mc_addr;
1219                release_sock(sk);
1220
1221                if (put_user(len, optlen))
1222                        return -EFAULT;
1223                if (copy_to_user(optval, &addr, len))
1224                        return -EFAULT;
1225                return 0;
1226        }
1227        case IP_MSFILTER:
1228        {
1229                struct ip_msfilter msf;
1230                int err;
1231
1232                if (len < IP_MSFILTER_SIZE(0)) {
1233                        release_sock(sk);
1234                        return -EINVAL;
1235                }
1236                if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1237                        release_sock(sk);
1238                        return -EFAULT;
1239                }
1240                err = ip_mc_msfget(sk, &msf,
1241                                   (struct ip_msfilter __user *)optval, optlen);
1242                release_sock(sk);
1243                return err;
1244        }
1245        case MCAST_MSFILTER:
1246        {
1247                struct group_filter gsf;
1248                int err;
1249
1250                if (len < GROUP_FILTER_SIZE(0)) {
1251                        release_sock(sk);
1252                        return -EINVAL;
1253                }
1254                if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1255                        release_sock(sk);
1256                        return -EFAULT;
1257                }
1258                err = ip_mc_gsfget(sk, &gsf,
1259                                   (struct group_filter __user *)optval,
1260                                   optlen);
1261                release_sock(sk);
1262                return err;
1263        }
1264        case IP_MULTICAST_ALL:
1265                val = inet->mc_all;
1266                break;
1267        case IP_PKTOPTIONS:
1268        {
1269                struct msghdr msg;
1270
1271                release_sock(sk);
1272
1273                if (sk->sk_type != SOCK_STREAM)
1274                        return -ENOPROTOOPT;
1275
1276                msg.msg_control = optval;
1277                msg.msg_controllen = len;
1278                msg.msg_flags = flags;
1279
1280                if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1281                        struct in_pktinfo info;
1282
1283                        info.ipi_addr.s_addr = inet->inet_rcv_saddr;
1284                        info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr;
1285                        info.ipi_ifindex = inet->mc_index;
1286                        put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1287                }
1288                if (inet->cmsg_flags & IP_CMSG_TTL) {
1289                        int hlim = inet->mc_ttl;
1290                        put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1291                }
1292                if (inet->cmsg_flags & IP_CMSG_TOS) {
1293                        int tos = inet->rcv_tos;
1294                        put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos);
1295                }
1296                len -= msg.msg_controllen;
1297                return put_user(len, optlen);
1298        }
1299        case IP_FREEBIND:
1300                val = inet->freebind;
1301                break;
1302        case IP_TRANSPARENT:
1303                val = inet->transparent;
1304                break;
1305        case IP_MINTTL:
1306                val = inet->min_ttl;
1307                break;
1308        default:
1309                release_sock(sk);
1310                return -ENOPROTOOPT;
1311        }
1312        release_sock(sk);
1313
1314        if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1315                unsigned char ucval = (unsigned char)val;
1316                len = 1;
1317                if (put_user(len, optlen))
1318                        return -EFAULT;
1319                if (copy_to_user(optval, &ucval, 1))
1320                        return -EFAULT;
1321        } else {
1322                len = min_t(unsigned int, sizeof(int), len);
1323                if (put_user(len, optlen))
1324                        return -EFAULT;
1325                if (copy_to_user(optval, &val, len))
1326                        return -EFAULT;
1327        }
1328        return 0;
1329}
1330
1331int ip_getsockopt(struct sock *sk, int level,
1332                  int optname, char __user *optval, int __user *optlen)
1333{
1334        int err;
1335
1336        err = do_ip_getsockopt(sk, level, optname, optval, optlen, 0);
1337#ifdef CONFIG_NETFILTER
1338        /* we need to exclude all possible ENOPROTOOPTs except default case */
1339        if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1340                        !ip_mroute_opt(optname)) {
1341                int len;
1342
1343                if (get_user(len, optlen))
1344                        return -EFAULT;
1345
1346                lock_sock(sk);
1347                err = nf_getsockopt(sk, PF_INET, optname, optval,
1348                                &len);
1349                release_sock(sk);
1350                if (err >= 0)
1351                        err = put_user(len, optlen);
1352                return err;
1353        }
1354#endif
1355        return err;
1356}
1357EXPORT_SYMBOL(ip_getsockopt);
1358
1359#ifdef CONFIG_COMPAT
1360int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1361                         char __user *optval, int __user *optlen)
1362{
1363        int err;
1364
1365        if (optname == MCAST_MSFILTER)
1366                return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1367                        ip_getsockopt);
1368
1369        err = do_ip_getsockopt(sk, level, optname, optval, optlen,
1370                MSG_CMSG_COMPAT);
1371
1372#ifdef CONFIG_NETFILTER
1373        /* we need to exclude all possible ENOPROTOOPTs except default case */
1374        if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1375                        !ip_mroute_opt(optname)) {
1376                int len;
1377
1378                if (get_user(len, optlen))
1379                        return -EFAULT;
1380
1381                lock_sock(sk);
1382                err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1383                release_sock(sk);
1384                if (err >= 0)
1385                        err = put_user(len, optlen);
1386                return err;
1387        }
1388#endif
1389        return err;
1390}
1391EXPORT_SYMBOL(compat_ip_getsockopt);
1392#endif
1393
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.