linux/net/ipv6/udp.c
<<
>>
Prefs
   1/*
   2 *      UDP over IPv6
   3 *      Linux INET6 implementation
   4 *
   5 *      Authors:
   6 *      Pedro Roque             <roque@di.fc.ul.pt>
   7 *
   8 *      Based on linux/ipv4/udp.c
   9 *
  10 *      Fixes:
  11 *      Hideaki YOSHIFUJI       :       sin6_scope_id support
  12 *      YOSHIFUJI Hideaki @USAGI and:   Support IPV6_V6ONLY socket option, which
  13 *      Alexey Kuznetsov                allow both IPv4 and IPv6 sockets to bind
  14 *                                      a single port at the same time.
  15 *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
  16 *      YOSHIFUJI Hideaki @USAGI:       convert /proc/net/udp6 to seq_file.
  17 *
  18 *      This program is free software; you can redistribute it and/or
  19 *      modify it under the terms of the GNU General Public License
  20 *      as published by the Free Software Foundation; either version
  21 *      2 of the License, or (at your option) any later version.
  22 */
  23
  24#include <linux/errno.h>
  25#include <linux/types.h>
  26#include <linux/socket.h>
  27#include <linux/sockios.h>
  28#include <linux/net.h>
  29#include <linux/in6.h>
  30#include <linux/netdevice.h>
  31#include <linux/if_arp.h>
  32#include <linux/ipv6.h>
  33#include <linux/icmpv6.h>
  34#include <linux/init.h>
  35#include <linux/module.h>
  36#include <linux/skbuff.h>
  37#include <linux/slab.h>
  38#include <asm/uaccess.h>
  39
  40#include <net/ndisc.h>
  41#include <net/protocol.h>
  42#include <net/transp_v6.h>
  43#include <net/ip6_route.h>
  44#include <net/raw.h>
  45#include <net/tcp_states.h>
  46#include <net/ip6_checksum.h>
  47#include <net/xfrm.h>
  48
  49#include <linux/proc_fs.h>
  50#include <linux/seq_file.h>
  51#include "udp_impl.h"
  52
  53int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
  54{
  55        const struct in6_addr *sk_rcv_saddr6 = &inet6_sk(sk)->rcv_saddr;
  56        const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
  57        __be32 sk1_rcv_saddr = sk_rcv_saddr(sk);
  58        __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2);
  59        int sk_ipv6only = ipv6_only_sock(sk);
  60        int sk2_ipv6only = inet_v6_ipv6only(sk2);
  61        int addr_type = ipv6_addr_type(sk_rcv_saddr6);
  62        int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
  63
  64        /* if both are mapped, treat as IPv4 */
  65        if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED)
  66                return (!sk2_ipv6only &&
  67                        (!sk1_rcv_saddr || !sk2_rcv_saddr ||
  68                          sk1_rcv_saddr == sk2_rcv_saddr));
  69
  70        if (addr_type2 == IPV6_ADDR_ANY &&
  71            !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
  72                return 1;
  73
  74        if (addr_type == IPV6_ADDR_ANY &&
  75            !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED))
  76                return 1;
  77
  78        if (sk2_rcv_saddr6 &&
  79            ipv6_addr_equal(sk_rcv_saddr6, sk2_rcv_saddr6))
  80                return 1;
  81
  82        return 0;
  83}
  84
  85static unsigned int udp6_portaddr_hash(struct net *net,
  86                                       const struct in6_addr *addr6,
  87                                       unsigned int port)
  88{
  89        unsigned int hash, mix = net_hash_mix(net);
  90
  91        if (ipv6_addr_any(addr6))
  92                hash = jhash_1word(0, mix);
  93        else if (ipv6_addr_v4mapped(addr6))
  94                hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
  95        else
  96                hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
  97
  98        return hash ^ port;
  99}
 100
 101
 102int udp_v6_get_port(struct sock *sk, unsigned short snum)
 103{
 104        unsigned int hash2_nulladdr =
 105                udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
 106        unsigned int hash2_partial = 
 107                udp6_portaddr_hash(sock_net(sk), &inet6_sk(sk)->rcv_saddr, 0);
 108
 109        /* precompute partial secondary hash */
 110        udp_sk(sk)->udp_portaddr_hash = hash2_partial;
 111        return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
 112}
 113
 114static void udp_v6_rehash(struct sock *sk)
 115{
 116        u16 new_hash = udp6_portaddr_hash(sock_net(sk),
 117                                          &inet6_sk(sk)->rcv_saddr,
 118                                          inet_sk(sk)->inet_num);
 119
 120        udp_lib_rehash(sk, new_hash);
 121}
 122
 123static inline int compute_score(struct sock *sk, struct net *net,
 124                                unsigned short hnum,
 125                                const struct in6_addr *saddr, __be16 sport,
 126                                const struct in6_addr *daddr, __be16 dport,
 127                                int dif)
 128{
 129        int score = -1;
 130
 131        if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
 132                        sk->sk_family == PF_INET6) {
 133                struct ipv6_pinfo *np = inet6_sk(sk);
 134                struct inet_sock *inet = inet_sk(sk);
 135
 136                score = 0;
 137                if (inet->inet_dport) {
 138                        if (inet->inet_dport != sport)
 139                                return -1;
 140                        score++;
 141                }
 142                if (!ipv6_addr_any(&np->rcv_saddr)) {
 143                        if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
 144                                return -1;
 145                        score++;
 146                }
 147                if (!ipv6_addr_any(&np->daddr)) {
 148                        if (!ipv6_addr_equal(&np->daddr, saddr))
 149                                return -1;
 150                        score++;
 151                }
 152                if (sk->sk_bound_dev_if) {
 153                        if (sk->sk_bound_dev_if != dif)
 154                                return -1;
 155                        score++;
 156                }
 157        }
 158        return score;
 159}
 160
 161#define SCORE2_MAX (1 + 1 + 1)
 162static inline int compute_score2(struct sock *sk, struct net *net,
 163                                const struct in6_addr *saddr, __be16 sport,
 164                                const struct in6_addr *daddr, unsigned short hnum,
 165                                int dif)
 166{
 167        int score = -1;
 168
 169        if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
 170                        sk->sk_family == PF_INET6) {
 171                struct ipv6_pinfo *np = inet6_sk(sk);
 172                struct inet_sock *inet = inet_sk(sk);
 173
 174                if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
 175                        return -1;
 176                score = 0;
 177                if (inet->inet_dport) {
 178                        if (inet->inet_dport != sport)
 179                                return -1;
 180                        score++;
 181                }
 182                if (!ipv6_addr_any(&np->daddr)) {
 183                        if (!ipv6_addr_equal(&np->daddr, saddr))
 184                                return -1;
 185                        score++;
 186                }
 187                if (sk->sk_bound_dev_if) {
 188                        if (sk->sk_bound_dev_if != dif)
 189                                return -1;
 190                        score++;
 191                }
 192        }
 193        return score;
 194}
 195
 196
 197/* called with read_rcu_lock() */
 198static struct sock *udp6_lib_lookup2(struct net *net,
 199                const struct in6_addr *saddr, __be16 sport,
 200                const struct in6_addr *daddr, unsigned int hnum, int dif,
 201                struct udp_hslot *hslot2, unsigned int slot2)
 202{
 203        struct sock *sk, *result;
 204        struct hlist_nulls_node *node;
 205        int score, badness;
 206
 207begin:
 208        result = NULL;
 209        badness = -1;
 210        udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
 211                score = compute_score2(sk, net, saddr, sport,
 212                                      daddr, hnum, dif);
 213                if (score > badness) {
 214                        result = sk;
 215                        badness = score;
 216                        if (score == SCORE2_MAX)
 217                                goto exact_match;
 218                }
 219        }
 220        /*
 221         * if the nulls value we got at the end of this lookup is
 222         * not the expected one, we must restart lookup.
 223         * We probably met an item that was moved to another chain.
 224         */
 225        if (get_nulls_value(node) != slot2)
 226                goto begin;
 227
 228        if (result) {
 229exact_match:
 230                if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 231                        result = NULL;
 232                else if (unlikely(compute_score2(result, net, saddr, sport,
 233                                  daddr, hnum, dif) < badness)) {
 234                        sock_put(result);
 235                        goto begin;
 236                }
 237        }
 238        return result;
 239}
 240
 241static struct sock *__udp6_lib_lookup(struct net *net,
 242                                      const struct in6_addr *saddr, __be16 sport,
 243                                      const struct in6_addr *daddr, __be16 dport,
 244                                      int dif, struct udp_table *udptable)
 245{
 246        struct sock *sk, *result;
 247        struct hlist_nulls_node *node;
 248        unsigned short hnum = ntohs(dport);
 249        unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
 250        struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
 251        int score, badness;
 252
 253        rcu_read_lock();
 254        if (hslot->count > 10) {
 255                hash2 = udp6_portaddr_hash(net, daddr, hnum);
 256                slot2 = hash2 & udptable->mask;
 257                hslot2 = &udptable->hash2[slot2];
 258                if (hslot->count < hslot2->count)
 259                        goto begin;
 260
 261                result = udp6_lib_lookup2(net, saddr, sport,
 262                                          daddr, hnum, dif,
 263                                          hslot2, slot2);
 264                if (!result) {
 265                        hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
 266                        slot2 = hash2 & udptable->mask;
 267                        hslot2 = &udptable->hash2[slot2];
 268                        if (hslot->count < hslot2->count)
 269                                goto begin;
 270
 271                        result = udp6_lib_lookup2(net, saddr, sport,
 272                                                  &in6addr_any, hnum, dif,
 273                                                  hslot2, slot2);
 274                }
 275                rcu_read_unlock();
 276                return result;
 277        }
 278begin:
 279        result = NULL;
 280        badness = -1;
 281        sk_nulls_for_each_rcu(sk, node, &hslot->head) {
 282                score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
 283                if (score > badness) {
 284                        result = sk;
 285                        badness = score;
 286                }
 287        }
 288        /*
 289         * if the nulls value we got at the end of this lookup is
 290         * not the expected one, we must restart lookup.
 291         * We probably met an item that was moved to another chain.
 292         */
 293        if (get_nulls_value(node) != slot)
 294                goto begin;
 295
 296        if (result) {
 297                if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 298                        result = NULL;
 299                else if (unlikely(compute_score(result, net, hnum, saddr, sport,
 300                                        daddr, dport, dif) < badness)) {
 301                        sock_put(result);
 302                        goto begin;
 303                }
 304        }
 305        rcu_read_unlock();
 306        return result;
 307}
 308
 309static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 310                                          __be16 sport, __be16 dport,
 311                                          struct udp_table *udptable)
 312{
 313        struct sock *sk;
 314        const struct ipv6hdr *iph = ipv6_hdr(skb);
 315
 316        if (unlikely(sk = skb_steal_sock(skb)))
 317                return sk;
 318        return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
 319                                 &iph->daddr, dport, inet6_iif(skb),
 320                                 udptable);
 321}
 322
 323struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 324                             const struct in6_addr *daddr, __be16 dport, int dif)
 325{
 326        return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
 327}
 328EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 329
 330
 331/*
 332 *      This should be easy, if there is something there we
 333 *      return it, otherwise we block.
 334 */
 335
 336int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 337                  struct msghdr *msg, size_t len,
 338                  int noblock, int flags, int *addr_len)
 339{
 340        struct ipv6_pinfo *np = inet6_sk(sk);
 341        struct inet_sock *inet = inet_sk(sk);
 342        struct sk_buff *skb;
 343        unsigned int ulen;
 344        int peeked;
 345        int err;
 346        int is_udplite = IS_UDPLITE(sk);
 347        int is_udp4;
 348        bool slow;
 349
 350        if (addr_len)
 351                *addr_len=sizeof(struct sockaddr_in6);
 352
 353        if (flags & MSG_ERRQUEUE)
 354                return ipv6_recv_error(sk, msg, len);
 355
 356        if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 357                return ipv6_recv_rxpmtu(sk, msg, len);
 358
 359try_again:
 360        skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
 361                                  &peeked, &err);
 362        if (!skb)
 363                goto out;
 364
 365        ulen = skb->len - sizeof(struct udphdr);
 366        if (len > ulen)
 367                len = ulen;
 368        else if (len < ulen)
 369                msg->msg_flags |= MSG_TRUNC;
 370
 371        is_udp4 = (skb->protocol == htons(ETH_P_IP));
 372
 373        /*
 374         * If checksum is needed at all, try to do it while copying the
 375         * data.  If the data is truncated, or if we only want a partial
 376         * coverage checksum (UDP-Lite), do it before the copy.
 377         */
 378
 379        if (len < ulen || UDP_SKB_CB(skb)->partial_cov) {
 380                if (udp_lib_checksum_complete(skb))
 381                        goto csum_copy_err;
 382        }
 383
 384        if (skb_csum_unnecessary(skb))
 385                err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
 386                                              msg->msg_iov,len);
 387        else {
 388                err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 389                if (err == -EINVAL)
 390                        goto csum_copy_err;
 391        }
 392        if (err)
 393                goto out_free;
 394
 395        if (!peeked) {
 396                if (is_udp4)
 397                        UDP_INC_STATS_USER(sock_net(sk),
 398                                        UDP_MIB_INDATAGRAMS, is_udplite);
 399                else
 400                        UDP6_INC_STATS_USER(sock_net(sk),
 401                                        UDP_MIB_INDATAGRAMS, is_udplite);
 402        }
 403
 404        sock_recv_ts_and_drops(msg, sk, skb);
 405
 406        /* Copy the address. */
 407        if (msg->msg_name) {
 408                struct sockaddr_in6 *sin6;
 409
 410                sin6 = (struct sockaddr_in6 *) msg->msg_name;
 411                sin6->sin6_family = AF_INET6;
 412                sin6->sin6_port = udp_hdr(skb)->source;
 413                sin6->sin6_flowinfo = 0;
 414                sin6->sin6_scope_id = 0;
 415
 416                if (is_udp4)
 417                        ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 418                                               &sin6->sin6_addr);
 419                else {
 420                        ipv6_addr_copy(&sin6->sin6_addr,
 421                                       &ipv6_hdr(skb)->saddr);
 422                        if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 423                                sin6->sin6_scope_id = IP6CB(skb)->iif;
 424                }
 425
 426        }
 427        if (is_udp4) {
 428                if (inet->cmsg_flags)
 429                        ip_cmsg_recv(msg, skb);
 430        } else {
 431                if (np->rxopt.all)
 432                        datagram_recv_ctl(sk, msg, skb);
 433        }
 434
 435        err = len;
 436        if (flags & MSG_TRUNC)
 437                err = ulen;
 438
 439out_free:
 440        skb_free_datagram_locked(sk, skb);
 441out:
 442        return err;
 443
 444csum_copy_err:
 445        slow = lock_sock_fast(sk);
 446        if (!skb_kill_datagram(sk, skb, flags)) {
 447                if (is_udp4)
 448                        UDP_INC_STATS_USER(sock_net(sk),
 449                                        UDP_MIB_INERRORS, is_udplite);
 450                else
 451                        UDP6_INC_STATS_USER(sock_net(sk),
 452                                        UDP_MIB_INERRORS, is_udplite);
 453        }
 454        unlock_sock_fast(sk, slow);
 455
 456        if (noblock)
 457                return -EAGAIN;
 458
 459        /* starting over for a new packet */
 460        msg->msg_flags &= ~MSG_TRUNC;
 461        goto try_again;
 462}
 463
 464void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 465                    u8 type, u8 code, int offset, __be32 info,
 466                    struct udp_table *udptable)
 467{
 468        struct ipv6_pinfo *np;
 469        const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 470        const struct in6_addr *saddr = &hdr->saddr;
 471        const struct in6_addr *daddr = &hdr->daddr;
 472        struct udphdr *uh = (struct udphdr*)(skb->data+offset);
 473        struct sock *sk;
 474        int err;
 475
 476        sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
 477                               saddr, uh->source, inet6_iif(skb), udptable);
 478        if (sk == NULL)
 479                return;
 480
 481        np = inet6_sk(sk);
 482
 483        if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
 484                goto out;
 485
 486        if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
 487                goto out;
 488
 489        if (np->recverr)
 490                ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 491
 492        sk->sk_err = err;
 493        sk->sk_error_report(sk);
 494out:
 495        sock_put(sk);
 496}
 497
 498static __inline__ void udpv6_err(struct sk_buff *skb,
 499                                 struct inet6_skb_parm *opt, u8 type,
 500                                 u8 code, int offset, __be32 info     )
 501{
 502        __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 503}
 504
 505int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
 506{
 507        struct udp_sock *up = udp_sk(sk);
 508        int rc;
 509        int is_udplite = IS_UDPLITE(sk);
 510
 511        if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
 512                sock_rps_save_rxhash(sk, skb->rxhash);
 513
 514        if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 515                goto drop;
 516
 517        /*
 518         * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 519         */
 520        if ((is_udplite & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 521
 522                if (up->pcrlen == 0) {          /* full coverage was set  */
 523                        LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
 524                                " %d while full coverage %d requested\n",
 525                                UDP_SKB_CB(skb)->cscov, skb->len);
 526                        goto drop;
 527                }
 528                if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 529                        LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
 530                                                    "too small, need min %d\n",
 531                                       UDP_SKB_CB(skb)->cscov, up->pcrlen);
 532                        goto drop;
 533                }
 534        }
 535
 536        if (rcu_dereference_raw(sk->sk_filter)) {
 537                if (udp_lib_checksum_complete(skb))
 538                        goto drop;
 539        }
 540
 541        if ((rc = ip_queue_rcv_skb(sk, skb)) < 0) {
 542                /* Note that an ENOMEM error is charged twice */
 543                if (rc == -ENOMEM)
 544                        UDP6_INC_STATS_BH(sock_net(sk),
 545                                        UDP_MIB_RCVBUFERRORS, is_udplite);
 546                goto drop_no_sk_drops_inc;
 547        }
 548
 549        return 0;
 550drop:
 551        atomic_inc(&sk->sk_drops);
 552drop_no_sk_drops_inc:
 553        UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 554        kfree_skb(skb);
 555        return -1;
 556}
 557
 558static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
 559                                      __be16 loc_port, const struct in6_addr *loc_addr,
 560                                      __be16 rmt_port, const struct in6_addr *rmt_addr,
 561                                      int dif)
 562{
 563        struct hlist_nulls_node *node;
 564        struct sock *s = sk;
 565        unsigned short num = ntohs(loc_port);
 566
 567        sk_nulls_for_each_from(s, node) {
 568                struct inet_sock *inet = inet_sk(s);
 569
 570                if (!net_eq(sock_net(s), net))
 571                        continue;
 572
 573                if (udp_sk(s)->udp_port_hash == num &&
 574                    s->sk_family == PF_INET6) {
 575                        struct ipv6_pinfo *np = inet6_sk(s);
 576                        if (inet->inet_dport) {
 577                                if (inet->inet_dport != rmt_port)
 578                                        continue;
 579                        }
 580                        if (!ipv6_addr_any(&np->daddr) &&
 581                            !ipv6_addr_equal(&np->daddr, rmt_addr))
 582                                continue;
 583
 584                        if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 585                                continue;
 586
 587                        if (!ipv6_addr_any(&np->rcv_saddr)) {
 588                                if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
 589                                        continue;
 590                        }
 591                        if (!inet6_mc_check(s, loc_addr, rmt_addr))
 592                                continue;
 593                        return s;
 594                }
 595        }
 596        return NULL;
 597}
 598
 599static void flush_stack(struct sock **stack, unsigned int count,
 600                        struct sk_buff *skb, unsigned int final)
 601{
 602        unsigned int i;
 603        struct sock *sk;
 604        struct sk_buff *skb1;
 605
 606        for (i = 0; i < count; i++) {
 607                skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
 608
 609                sk = stack[i];
 610                if (skb1) {
 611                        if (sk_rcvqueues_full(sk, skb1)) {
 612                                kfree_skb(skb1);
 613                                goto drop;
 614                        }
 615                        bh_lock_sock(sk);
 616                        if (!sock_owned_by_user(sk))
 617                                udpv6_queue_rcv_skb(sk, skb1);
 618                        else if (sk_add_backlog(sk, skb1)) {
 619                                kfree_skb(skb1);
 620                                bh_unlock_sock(sk);
 621                                goto drop;
 622                        }
 623                        bh_unlock_sock(sk);
 624                        continue;
 625                }
 626drop:
 627                atomic_inc(&sk->sk_drops);
 628                UDP6_INC_STATS_BH(sock_net(sk),
 629                                UDP_MIB_RCVBUFERRORS, IS_UDPLITE(sk));
 630                UDP6_INC_STATS_BH(sock_net(sk),
 631                                UDP_MIB_INERRORS, IS_UDPLITE(sk));
 632        }
 633}
 634/*
 635 * Note: called only from the BH handler context,
 636 * so we don't need to lock the hashes.
 637 */
 638static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 639                const struct in6_addr *saddr, const struct in6_addr *daddr,
 640                struct udp_table *udptable)
 641{
 642        struct sock *sk, *stack[256 / sizeof(struct sock *)];
 643        const struct udphdr *uh = udp_hdr(skb);
 644        struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
 645        int dif;
 646        unsigned int i, count = 0;
 647
 648        spin_lock(&hslot->lock);
 649        sk = sk_nulls_head(&hslot->head);
 650        dif = inet6_iif(skb);
 651        sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
 652        while (sk) {
 653                stack[count++] = sk;
 654                sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
 655                                       uh->source, saddr, dif);
 656                if (unlikely(count == ARRAY_SIZE(stack))) {
 657                        if (!sk)
 658                                break;
 659                        flush_stack(stack, count, skb, ~0);
 660                        count = 0;
 661                }
 662        }
 663        /*
 664         * before releasing the lock, we must take reference on sockets
 665         */
 666        for (i = 0; i < count; i++)
 667                sock_hold(stack[i]);
 668
 669        spin_unlock(&hslot->lock);
 670
 671        if (count) {
 672                flush_stack(stack, count, skb, count - 1);
 673
 674                for (i = 0; i < count; i++)
 675                        sock_put(stack[i]);
 676        } else {
 677                kfree_skb(skb);
 678        }
 679        return 0;
 680}
 681
 682static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh,
 683                                 int proto)
 684{
 685        int err;
 686
 687        UDP_SKB_CB(skb)->partial_cov = 0;
 688        UDP_SKB_CB(skb)->cscov = skb->len;
 689
 690        if (proto == IPPROTO_UDPLITE) {
 691                err = udplite_checksum_init(skb, uh);
 692                if (err)
 693                        return err;
 694        }
 695
 696        if (uh->check == 0) {
 697                /* RFC 2460 section 8.1 says that we SHOULD log
 698                   this error. Well, it is reasonable.
 699                 */
 700                LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
 701                return 1;
 702        }
 703        if (skb->ip_summed == CHECKSUM_COMPLETE &&
 704            !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
 705                             skb->len, proto, skb->csum))
 706                skb->ip_summed = CHECKSUM_UNNECESSARY;
 707
 708        if (!skb_csum_unnecessary(skb))
 709                skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
 710                                                         &ipv6_hdr(skb)->daddr,
 711                                                         skb->len, proto, 0));
 712
 713        return 0;
 714}
 715
 716int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 717                   int proto)
 718{
 719        struct net *net = dev_net(skb->dev);
 720        struct sock *sk;
 721        struct udphdr *uh;
 722        const struct in6_addr *saddr, *daddr;
 723        u32 ulen = 0;
 724
 725        if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 726                goto discard;
 727
 728        saddr = &ipv6_hdr(skb)->saddr;
 729        daddr = &ipv6_hdr(skb)->daddr;
 730        uh = udp_hdr(skb);
 731
 732        ulen = ntohs(uh->len);
 733        if (ulen > skb->len)
 734                goto short_packet;
 735
 736        if (proto == IPPROTO_UDP) {
 737                /* UDP validates ulen. */
 738
 739                /* Check for jumbo payload */
 740                if (ulen == 0)
 741                        ulen = skb->len;
 742
 743                if (ulen < sizeof(*uh))
 744                        goto short_packet;
 745
 746                if (ulen < skb->len) {
 747                        if (pskb_trim_rcsum(skb, ulen))
 748                                goto short_packet;
 749                        saddr = &ipv6_hdr(skb)->saddr;
 750                        daddr = &ipv6_hdr(skb)->daddr;
 751                        uh = udp_hdr(skb);
 752                }
 753        }
 754
 755        if (udp6_csum_init(skb, uh, proto))
 756                goto discard;
 757
 758        /*
 759         *      Multicast receive code
 760         */
 761        if (ipv6_addr_is_multicast(daddr))
 762                return __udp6_lib_mcast_deliver(net, skb,
 763                                saddr, daddr, udptable);
 764
 765        /* Unicast */
 766
 767        /*
 768         * check socket cache ... must talk to Alan about his plans
 769         * for sock caches... i'll skip this for now.
 770         */
 771        sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
 772
 773        if (sk == NULL) {
 774                if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 775                        goto discard;
 776
 777                if (udp_lib_checksum_complete(skb))
 778                        goto discard;
 779                UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS,
 780                                proto == IPPROTO_UDPLITE);
 781
 782                icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 783
 784                kfree_skb(skb);
 785                return 0;
 786        }
 787
 788        /* deliver */
 789
 790        if (sk_rcvqueues_full(sk, skb)) {
 791                sock_put(sk);
 792                goto discard;
 793        }
 794        bh_lock_sock(sk);
 795        if (!sock_owned_by_user(sk))
 796                udpv6_queue_rcv_skb(sk, skb);
 797        else if (sk_add_backlog(sk, skb)) {
 798                atomic_inc(&sk->sk_drops);
 799                bh_unlock_sock(sk);
 800                sock_put(sk);
 801                goto discard;
 802        }
 803        bh_unlock_sock(sk);
 804        sock_put(sk);
 805        return 0;
 806
 807short_packet:
 808        LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
 809                       proto == IPPROTO_UDPLITE ? "-Lite" : "",
 810                       saddr,
 811                       ntohs(uh->source),
 812                       ulen,
 813                       skb->len,
 814                       daddr,
 815                       ntohs(uh->dest));
 816
 817discard:
 818        UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
 819        kfree_skb(skb);
 820        return 0;
 821}
 822
 823static __inline__ int udpv6_rcv(struct sk_buff *skb)
 824{
 825        return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
 826}
 827
 828/*
 829 * Throw away all pending data and cancel the corking. Socket is locked.
 830 */
 831static void udp_v6_flush_pending_frames(struct sock *sk)
 832{
 833        struct udp_sock *up = udp_sk(sk);
 834
 835        if (up->pending == AF_INET)
 836                udp_flush_pending_frames(sk);
 837        else if (up->pending) {
 838                up->len = 0;
 839                up->pending = 0;
 840                ip6_flush_pending_frames(sk);
 841        }
 842}
 843
 844/**
 845 *      udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
 846 *      @sk:    socket we are sending on
 847 *      @skb:   sk_buff containing the filled-in UDP header
 848 *              (checksum field must be zeroed out)
 849 */
 850static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
 851                                 const struct in6_addr *saddr,
 852                                 const struct in6_addr *daddr, int len)
 853{
 854        unsigned int offset;
 855        struct udphdr *uh = udp_hdr(skb);
 856        __wsum csum = 0;
 857
 858        if (skb_queue_len(&sk->sk_write_queue) == 1) {
 859                /* Only one fragment on the socket.  */
 860                skb->csum_start = skb_transport_header(skb) - skb->head;
 861                skb->csum_offset = offsetof(struct udphdr, check);
 862                uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
 863        } else {
 864                /*
 865                 * HW-checksum won't work as there are two or more
 866                 * fragments on the socket so that all csums of sk_buffs
 867                 * should be together
 868                 */
 869                offset = skb_transport_offset(skb);
 870                skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
 871
 872                skb->ip_summed = CHECKSUM_NONE;
 873
 874                skb_queue_walk(&sk->sk_write_queue, skb) {
 875                        csum = csum_add(csum, skb->csum);
 876                }
 877
 878                uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
 879                                            csum);
 880                if (uh->check == 0)
 881                        uh->check = CSUM_MANGLED_0;
 882        }
 883}
 884
 885/*
 886 *      Sending
 887 */
 888
 889static int udp_v6_push_pending_frames(struct sock *sk)
 890{
 891        struct sk_buff *skb;
 892        struct udphdr *uh;
 893        struct udp_sock  *up = udp_sk(sk);
 894        struct inet_sock *inet = inet_sk(sk);
 895        struct flowi6 *fl6 = &inet->cork.fl.u.ip6;
 896        int err = 0;
 897        int is_udplite = IS_UDPLITE(sk);
 898        __wsum csum = 0;
 899
 900        /* Grab the skbuff where UDP header space exists. */
 901        if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 902                goto out;
 903
 904        /*
 905         * Create a UDP header
 906         */
 907        uh = udp_hdr(skb);
 908        uh->source = fl6->fl6_sport;
 909        uh->dest = fl6->fl6_dport;
 910        uh->len = htons(up->len);
 911        uh->check = 0;
 912
 913        if (is_udplite)
 914                csum = udplite_csum_outgoing(sk, skb);
 915        else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
 916                udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
 917                                     up->len);
 918                goto send;
 919        } else
 920                csum = udp_csum_outgoing(sk, skb);
 921
 922        /* add protocol-dependent pseudo-header */
 923        uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
 924                                    up->len, fl6->flowi6_proto, csum);
 925        if (uh->check == 0)
 926                uh->check = CSUM_MANGLED_0;
 927
 928send:
 929        err = ip6_push_pending_frames(sk);
 930        if (err) {
 931                if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
 932                        UDP6_INC_STATS_USER(sock_net(sk),
 933                                            UDP_MIB_SNDBUFERRORS, is_udplite);
 934                        err = 0;
 935                }
 936        } else
 937                UDP6_INC_STATS_USER(sock_net(sk),
 938                                    UDP_MIB_OUTDATAGRAMS, is_udplite);
 939out:
 940        up->len = 0;
 941        up->pending = 0;
 942        return err;
 943}
 944
 945int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 946                  struct msghdr *msg, size_t len)
 947{
 948        struct ipv6_txoptions opt_space;
 949        struct udp_sock *up = udp_sk(sk);
 950        struct inet_sock *inet = inet_sk(sk);
 951        struct ipv6_pinfo *np = inet6_sk(sk);
 952        struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
 953        struct in6_addr *daddr, *final_p, final;
 954        struct ipv6_txoptions *opt = NULL;
 955        struct ip6_flowlabel *flowlabel = NULL;
 956        struct flowi6 fl6;
 957        struct dst_entry *dst;
 958        int addr_len = msg->msg_namelen;
 959        int ulen = len;
 960        int hlimit = -1;
 961        int tclass = -1;
 962        int dontfrag = -1;
 963        int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
 964        int err;
 965        int connected = 0;
 966        int is_udplite = IS_UDPLITE(sk);
 967        int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
 968
 969        /* destination address check */
 970        if (sin6) {
 971                if (addr_len < offsetof(struct sockaddr, sa_data))
 972                        return -EINVAL;
 973
 974                switch (sin6->sin6_family) {
 975                case AF_INET6:
 976                        if (addr_len < SIN6_LEN_RFC2133)
 977                                return -EINVAL;
 978                        daddr = &sin6->sin6_addr;
 979                        break;
 980                case AF_INET:
 981                        goto do_udp_sendmsg;
 982                case AF_UNSPEC:
 983                        msg->msg_name = sin6 = NULL;
 984                        msg->msg_namelen = addr_len = 0;
 985                        daddr = NULL;
 986                        break;
 987                default:
 988                        return -EINVAL;
 989                }
 990        } else if (!up->pending) {
 991                if (sk->sk_state != TCP_ESTABLISHED)
 992                        return -EDESTADDRREQ;
 993                daddr = &np->daddr;
 994        } else
 995                daddr = NULL;
 996
 997        if (daddr) {
 998                if (ipv6_addr_v4mapped(daddr)) {
 999                        struct sockaddr_in sin;
1000                        sin.sin_family = AF_INET;
1001                        sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1002                        sin.sin_addr.s_addr = daddr->s6_addr32[3];
1003                        msg->msg_name = &sin;
1004                        msg->msg_namelen = sizeof(sin);
1005do_udp_sendmsg:
1006                        if (__ipv6_only_sock(sk))
1007                                return -ENETUNREACH;
1008                        return udp_sendmsg(iocb, sk, msg, len);
1009                }
1010        }
1011
1012        if (up->pending == AF_INET)
1013                return udp_sendmsg(iocb, sk, msg, len);
1014
1015        /* Rough check on arithmetic overflow,
1016           better check is made in ip6_append_data().
1017           */
1018        if (len > INT_MAX - sizeof(struct udphdr))
1019                return -EMSGSIZE;
1020
1021        if (up->pending) {
1022                /*
1023                 * There are pending frames.
1024                 * The socket lock must be held while it's corked.
1025                 */
1026                lock_sock(sk);
1027                if (likely(up->pending)) {
1028                        if (unlikely(up->pending != AF_INET6)) {
1029                                release_sock(sk);
1030                                return -EAFNOSUPPORT;
1031                        }
1032                        dst = NULL;
1033                        goto do_append_data;
1034                }
1035                release_sock(sk);
1036        }
1037        ulen += sizeof(struct udphdr);
1038
1039        memset(&fl6, 0, sizeof(fl6));
1040
1041        if (sin6) {
1042                if (sin6->sin6_port == 0)
1043                        return -EINVAL;
1044
1045                fl6.fl6_dport = sin6->sin6_port;
1046                daddr = &sin6->sin6_addr;
1047
1048                if (np->sndflow) {
1049                        fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1050                        if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1051                                flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1052                                if (flowlabel == NULL)
1053                                        return -EINVAL;
1054                                daddr = &flowlabel->dst;
1055                        }
1056                }
1057
1058                /*
1059                 * Otherwise it will be difficult to maintain
1060                 * sk->sk_dst_cache.
1061                 */
1062                if (sk->sk_state == TCP_ESTABLISHED &&
1063                    ipv6_addr_equal(daddr, &np->daddr))
1064                        daddr = &np->daddr;
1065
1066                if (addr_len >= sizeof(struct sockaddr_in6) &&
1067                    sin6->sin6_scope_id &&
1068                    ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
1069                        fl6.flowi6_oif = sin6->sin6_scope_id;
1070        } else {
1071                if (sk->sk_state != TCP_ESTABLISHED)
1072                        return -EDESTADDRREQ;
1073
1074                fl6.fl6_dport = inet->inet_dport;
1075                daddr = &np->daddr;
1076                fl6.flowlabel = np->flow_label;
1077                connected = 1;
1078        }
1079
1080        if (!fl6.flowi6_oif)
1081                fl6.flowi6_oif = sk->sk_bound_dev_if;
1082
1083        if (!fl6.flowi6_oif)
1084                fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1085
1086        fl6.flowi6_mark = sk->sk_mark;
1087
1088        if (msg->msg_controllen) {
1089                opt = &opt_space;
1090                memset(opt, 0, sizeof(struct ipv6_txoptions));
1091                opt->tot_len = sizeof(*opt);
1092
1093                err = datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1094                                        &hlimit, &tclass, &dontfrag);
1095                if (err < 0) {
1096                        fl6_sock_release(flowlabel);
1097                        return err;
1098                }
1099                if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1100                        flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1101                        if (flowlabel == NULL)
1102                                return -EINVAL;
1103                }
1104                if (!(opt->opt_nflen|opt->opt_flen))
1105                        opt = NULL;
1106                connected = 0;
1107        }
1108        if (opt == NULL)
1109                opt = np->opt;
1110        if (flowlabel)
1111                opt = fl6_merge_options(&opt_space, flowlabel, opt);
1112        opt = ipv6_fixup_options(&opt_space, opt);
1113
1114        fl6.flowi6_proto = sk->sk_protocol;
1115        if (!ipv6_addr_any(daddr))
1116                ipv6_addr_copy(&fl6.daddr, daddr);
1117        else
1118                fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1119        if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1120                ipv6_addr_copy(&fl6.saddr, &np->saddr);
1121        fl6.fl6_sport = inet->inet_sport;
1122
1123        final_p = fl6_update_dst(&fl6, opt, &final);
1124        if (final_p)
1125                connected = 0;
1126
1127        if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1128                fl6.flowi6_oif = np->mcast_oif;
1129                connected = 0;
1130        }
1131
1132        security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1133
1134        dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, true);
1135        if (IS_ERR(dst)) {
1136                err = PTR_ERR(dst);
1137                dst = NULL;
1138                goto out;
1139        }
1140
1141        if (hlimit < 0) {
1142                if (ipv6_addr_is_multicast(&fl6.daddr))
1143                        hlimit = np->mcast_hops;
1144                else
1145                        hlimit = np->hop_limit;
1146                if (hlimit < 0)
1147                        hlimit = ip6_dst_hoplimit(dst);
1148        }
1149
1150        if (tclass < 0)
1151                tclass = np->tclass;
1152
1153        if (dontfrag < 0)
1154                dontfrag = np->dontfrag;
1155
1156        if (msg->msg_flags&MSG_CONFIRM)
1157                goto do_confirm;
1158back_from_confirm:
1159
1160        lock_sock(sk);
1161        if (unlikely(up->pending)) {
1162                /* The socket is already corked while preparing it. */
1163                /* ... which is an evident application bug. --ANK */
1164                release_sock(sk);
1165
1166                LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1167                err = -EINVAL;
1168                goto out;
1169        }
1170
1171        up->pending = AF_INET6;
1172
1173do_append_data:
1174        up->len += ulen;
1175        getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1176        err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1177                sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1178                (struct rt6_info*)dst,
1179                corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1180        if (err)
1181                udp_v6_flush_pending_frames(sk);
1182        else if (!corkreq)
1183                err = udp_v6_push_pending_frames(sk);
1184        else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1185                up->pending = 0;
1186
1187        if (dst) {
1188                if (connected) {
1189                        ip6_dst_store(sk, dst,
1190                                      ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
1191                                      &np->daddr : NULL,
1192#ifdef CONFIG_IPV6_SUBTREES
1193                                      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1194                                      &np->saddr :
1195#endif
1196                                      NULL);
1197                } else {
1198                        dst_release(dst);
1199                }
1200                dst = NULL;
1201        }
1202
1203        if (err > 0)
1204                err = np->recverr ? net_xmit_errno(err) : 0;
1205        release_sock(sk);
1206out:
1207        dst_release(dst);
1208        fl6_sock_release(flowlabel);
1209        if (!err)
1210                return len;
1211        /*
1212         * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1213         * ENOBUFS might not be good (it's not tunable per se), but otherwise
1214         * we don't have a good statistic (IpOutDiscards but it can be too many
1215         * things).  We could add another new stat but at least for now that
1216         * seems like overkill.
1217         */
1218        if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1219                UDP6_INC_STATS_USER(sock_net(sk),
1220                                UDP_MIB_SNDBUFERRORS, is_udplite);
1221        }
1222        return err;
1223
1224do_confirm:
1225        dst_confirm(dst);
1226        if (!(msg->msg_flags&MSG_PROBE) || len)
1227                goto back_from_confirm;
1228        err = 0;
1229        goto out;
1230}
1231
1232void udpv6_destroy_sock(struct sock *sk)
1233{
1234        lock_sock(sk);
1235        udp_v6_flush_pending_frames(sk);
1236        release_sock(sk);
1237
1238        inet6_destroy_sock(sk);
1239}
1240
1241/*
1242 *      Socket option code for UDP
1243 */
1244int udpv6_setsockopt(struct sock *sk, int level, int optname,
1245                     char __user *optval, unsigned int optlen)
1246{
1247        if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1248                return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1249                                          udp_v6_push_pending_frames);
1250        return ipv6_setsockopt(sk, level, optname, optval, optlen);
1251}
1252
1253#ifdef CONFIG_COMPAT
1254int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1255                            char __user *optval, unsigned int optlen)
1256{
1257        if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1258                return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1259                                          udp_v6_push_pending_frames);
1260        return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1261}
1262#endif
1263
1264int udpv6_getsockopt(struct sock *sk, int level, int optname,
1265                     char __user *optval, int __user *optlen)
1266{
1267        if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1268                return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1269        return ipv6_getsockopt(sk, level, optname, optval, optlen);
1270}
1271
1272#ifdef CONFIG_COMPAT
1273int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1274                            char __user *optval, int __user *optlen)
1275{
1276        if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1277                return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1278        return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1279}
1280#endif
1281
1282static int udp6_ufo_send_check(struct sk_buff *skb)
1283{
1284        const struct ipv6hdr *ipv6h;
1285        struct udphdr *uh;
1286
1287        if (!pskb_may_pull(skb, sizeof(*uh)))
1288                return -EINVAL;
1289
1290        ipv6h = ipv6_hdr(skb);
1291        uh = udp_hdr(skb);
1292
1293        uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
1294                                     IPPROTO_UDP, 0);
1295        skb->csum_start = skb_transport_header(skb) - skb->head;
1296        skb->csum_offset = offsetof(struct udphdr, check);
1297        skb->ip_summed = CHECKSUM_PARTIAL;
1298        return 0;
1299}
1300
1301static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, u32 features)
1302{
1303        struct sk_buff *segs = ERR_PTR(-EINVAL);
1304        unsigned int mss;
1305        unsigned int unfrag_ip6hlen, unfrag_len;
1306        struct frag_hdr *fptr;
1307        u8 *mac_start, *prevhdr;
1308        u8 nexthdr;
1309        u8 frag_hdr_sz = sizeof(struct frag_hdr);
1310        int offset;
1311        __wsum csum;
1312
1313        mss = skb_shinfo(skb)->gso_size;
1314        if (unlikely(skb->len <= mss))
1315                goto out;
1316
1317        if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
1318                /* Packet is from an untrusted source, reset gso_segs. */
1319                int type = skb_shinfo(skb)->gso_type;
1320
1321                if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
1322                             !(type & (SKB_GSO_UDP))))
1323                        goto out;
1324
1325                skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
1326
1327                segs = NULL;
1328                goto out;
1329        }
1330
1331        /* Do software UFO. Complete and fill in the UDP checksum as HW cannot
1332         * do checksum of UDP packets sent as multiple IP fragments.
1333         */
1334        offset = skb_checksum_start_offset(skb);
1335        csum = skb_checksum(skb, offset, skb->len- offset, 0);
1336        offset += skb->csum_offset;
1337        *(__sum16 *)(skb->data + offset) = csum_fold(csum);
1338        skb->ip_summed = CHECKSUM_NONE;
1339
1340        /* Check if there is enough headroom to insert fragment header. */
1341        if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) &&
1342            pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
1343                goto out;
1344
1345        /* Find the unfragmentable header and shift it left by frag_hdr_sz
1346         * bytes to insert fragment header.
1347         */
1348        unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
1349        nexthdr = *prevhdr;
1350        *prevhdr = NEXTHDR_FRAGMENT;
1351        unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
1352                     unfrag_ip6hlen;
1353        mac_start = skb_mac_header(skb);
1354        memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
1355
1356        skb->mac_header -= frag_hdr_sz;
1357        skb->network_header -= frag_hdr_sz;
1358
1359        fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
1360        fptr->nexthdr = nexthdr;
1361        fptr->reserved = 0;
1362        ipv6_select_ident(fptr, (struct rt6_info *)skb_dst(skb));
1363
1364        /* Fragment the skb. ipv6 header and the remaining fields of the
1365         * fragment header are updated in ipv6_gso_segment()
1366         */
1367        segs = skb_segment(skb, features);
1368
1369out:
1370        return segs;
1371}
1372
1373static const struct inet6_protocol udpv6_protocol = {
1374        .handler        =       udpv6_rcv,
1375        .err_handler    =       udpv6_err,
1376        .gso_send_check =       udp6_ufo_send_check,
1377        .gso_segment    =       udp6_ufo_fragment,
1378        .flags          =       INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1379};
1380
1381/* ------------------------------------------------------------------------ */
1382#ifdef CONFIG_PROC_FS
1383
1384static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1385{
1386        struct inet_sock *inet = inet_sk(sp);
1387        struct ipv6_pinfo *np = inet6_sk(sp);
1388        const struct in6_addr *dest, *src;
1389        __u16 destp, srcp;
1390
1391        dest  = &np->daddr;
1392        src   = &np->rcv_saddr;
1393        destp = ntohs(inet->inet_dport);
1394        srcp  = ntohs(inet->inet_sport);
1395        seq_printf(seq,
1396                   "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1397                   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d\n",
1398                   bucket,
1399                   src->s6_addr32[0], src->s6_addr32[1],
1400                   src->s6_addr32[2], src->s6_addr32[3], srcp,
1401                   dest->s6_addr32[0], dest->s6_addr32[1],
1402                   dest->s6_addr32[2], dest->s6_addr32[3], destp,
1403                   sp->sk_state,
1404                   sk_wmem_alloc_get(sp),
1405                   sk_rmem_alloc_get(sp),
1406                   0, 0L, 0,
1407                   sock_i_uid(sp), 0,
1408                   sock_i_ino(sp),
1409                   atomic_read(&sp->sk_refcnt), sp,
1410                   atomic_read(&sp->sk_drops));
1411}
1412
1413int udp6_seq_show(struct seq_file *seq, void *v)
1414{
1415        if (v == SEQ_START_TOKEN)
1416                seq_printf(seq,
1417                           "  sl  "
1418                           "local_address                         "
1419                           "remote_address                        "
1420                           "st tx_queue rx_queue tr tm->when retrnsmt"
1421                           "   uid  timeout inode ref pointer drops\n");
1422        else
1423                udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1424        return 0;
1425}
1426
1427static struct udp_seq_afinfo udp6_seq_afinfo = {
1428        .name           = "udp6",
1429        .family         = AF_INET6,
1430        .udp_table      = &udp_table,
1431        .seq_fops       = {
1432                .owner  =       THIS_MODULE,
1433        },
1434        .seq_ops        = {
1435                .show           = udp6_seq_show,
1436        },
1437};
1438
1439int __net_init udp6_proc_init(struct net *net)
1440{
1441        return udp_proc_register(net, &udp6_seq_afinfo);
1442}
1443
1444void udp6_proc_exit(struct net *net) {
1445        udp_proc_unregister(net, &udp6_seq_afinfo);
1446}
1447#endif /* CONFIG_PROC_FS */
1448
1449/* ------------------------------------------------------------------------ */
1450
1451struct proto udpv6_prot = {
1452        .name              = "UDPv6",
1453        .owner             = THIS_MODULE,
1454        .close             = udp_lib_close,
1455        .connect           = ip6_datagram_connect,
1456        .disconnect        = udp_disconnect,
1457        .ioctl             = udp_ioctl,
1458        .destroy           = udpv6_destroy_sock,
1459        .setsockopt        = udpv6_setsockopt,
1460        .getsockopt        = udpv6_getsockopt,
1461        .sendmsg           = udpv6_sendmsg,
1462        .recvmsg           = udpv6_recvmsg,
1463        .backlog_rcv       = udpv6_queue_rcv_skb,
1464        .hash              = udp_lib_hash,
1465        .unhash            = udp_lib_unhash,
1466        .rehash            = udp_v6_rehash,
1467        .get_port          = udp_v6_get_port,
1468        .memory_allocated  = &udp_memory_allocated,
1469        .sysctl_mem        = sysctl_udp_mem,
1470        .sysctl_wmem       = &sysctl_udp_wmem_min,
1471        .sysctl_rmem       = &sysctl_udp_rmem_min,
1472        .obj_size          = sizeof(struct udp6_sock),
1473        .slab_flags        = SLAB_DESTROY_BY_RCU,
1474        .h.udp_table       = &udp_table,
1475#ifdef CONFIG_COMPAT
1476        .compat_setsockopt = compat_udpv6_setsockopt,
1477        .compat_getsockopt = compat_udpv6_getsockopt,
1478#endif
1479        .clear_sk          = sk_prot_clear_portaddr_nulls,
1480};
1481
1482static struct inet_protosw udpv6_protosw = {
1483        .type =      SOCK_DGRAM,
1484        .protocol =  IPPROTO_UDP,
1485        .prot =      &udpv6_prot,
1486        .ops =       &inet6_dgram_ops,
1487        .no_check =  UDP_CSUM_DEFAULT,
1488        .flags =     INET_PROTOSW_PERMANENT,
1489};
1490
1491
1492int __init udpv6_init(void)
1493{
1494        int ret;
1495
1496        ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1497        if (ret)
1498                goto out;
1499
1500        ret = inet6_register_protosw(&udpv6_protosw);
1501        if (ret)
1502                goto out_udpv6_protocol;
1503out:
1504        return ret;
1505
1506out_udpv6_protocol:
1507        inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1508        goto out;
1509}
1510
1511void udpv6_exit(void)
1512{
1513        inet6_unregister_protosw(&udpv6_protosw);
1514        inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1515}
1516