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v3.1
   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}
v3.15
   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#include <net/inet6_hashtables.h>
  49#include <net/busy_poll.h>
  50
  51#include <linux/proc_fs.h>
  52#include <linux/seq_file.h>
  53#include <trace/events/skb.h>
  54#include "udp_impl.h"
  55
  56static unsigned int udp6_ehashfn(struct net *net,
  57				  const struct in6_addr *laddr,
  58				  const u16 lport,
  59				  const struct in6_addr *faddr,
  60				  const __be16 fport)
  61{
  62	static u32 udp6_ehash_secret __read_mostly;
  63	static u32 udp_ipv6_hash_secret __read_mostly;
  64
  65	u32 lhash, fhash;
  66
  67	net_get_random_once(&udp6_ehash_secret,
  68			    sizeof(udp6_ehash_secret));
  69	net_get_random_once(&udp_ipv6_hash_secret,
  70			    sizeof(udp_ipv6_hash_secret));
  71
  72	lhash = (__force u32)laddr->s6_addr32[3];
  73	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
  74
  75	return __inet6_ehashfn(lhash, lport, fhash, fport,
  76			       udp_ipv6_hash_secret + net_hash_mix(net));
  77}
  78
  79int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
  80{
 
  81	const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
 
 
  82	int sk_ipv6only = ipv6_only_sock(sk);
  83	int sk2_ipv6only = inet_v6_ipv6only(sk2);
  84	int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
  85	int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
  86
  87	/* if both are mapped, treat as IPv4 */
  88	if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED)
  89		return (!sk2_ipv6only &&
  90			(!sk->sk_rcv_saddr || !sk2->sk_rcv_saddr ||
  91			  sk->sk_rcv_saddr == sk2->sk_rcv_saddr));
  92
  93	if (addr_type2 == IPV6_ADDR_ANY &&
  94	    !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
  95		return 1;
  96
  97	if (addr_type == IPV6_ADDR_ANY &&
  98	    !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED))
  99		return 1;
 100
 101	if (sk2_rcv_saddr6 &&
 102	    ipv6_addr_equal(&sk->sk_v6_rcv_saddr, sk2_rcv_saddr6))
 103		return 1;
 104
 105	return 0;
 106}
 107
 108static unsigned int udp6_portaddr_hash(struct net *net,
 109				       const struct in6_addr *addr6,
 110				       unsigned int port)
 111{
 112	unsigned int hash, mix = net_hash_mix(net);
 113
 114	if (ipv6_addr_any(addr6))
 115		hash = jhash_1word(0, mix);
 116	else if (ipv6_addr_v4mapped(addr6))
 117		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
 118	else
 119		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
 120
 121	return hash ^ port;
 122}
 123
 124
 125int udp_v6_get_port(struct sock *sk, unsigned short snum)
 126{
 127	unsigned int hash2_nulladdr =
 128		udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
 129	unsigned int hash2_partial =
 130		udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
 131
 132	/* precompute partial secondary hash */
 133	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
 134	return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
 135}
 136
 137static void udp_v6_rehash(struct sock *sk)
 138{
 139	u16 new_hash = udp6_portaddr_hash(sock_net(sk),
 140					  &sk->sk_v6_rcv_saddr,
 141					  inet_sk(sk)->inet_num);
 142
 143	udp_lib_rehash(sk, new_hash);
 144}
 145
 146static inline int compute_score(struct sock *sk, struct net *net,
 147				unsigned short hnum,
 148				const struct in6_addr *saddr, __be16 sport,
 149				const struct in6_addr *daddr, __be16 dport,
 150				int dif)
 151{
 152	int score = -1;
 153
 154	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
 155			sk->sk_family == PF_INET6) {
 
 156		struct inet_sock *inet = inet_sk(sk);
 157
 158		score = 0;
 159		if (inet->inet_dport) {
 160			if (inet->inet_dport != sport)
 161				return -1;
 162			score++;
 163		}
 164		if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
 165			if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 166				return -1;
 167			score++;
 168		}
 169		if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 170			if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 171				return -1;
 172			score++;
 173		}
 174		if (sk->sk_bound_dev_if) {
 175			if (sk->sk_bound_dev_if != dif)
 176				return -1;
 177			score++;
 178		}
 179	}
 180	return score;
 181}
 182
 183#define SCORE2_MAX (1 + 1 + 1)
 184static inline int compute_score2(struct sock *sk, struct net *net,
 185				const struct in6_addr *saddr, __be16 sport,
 186				const struct in6_addr *daddr, unsigned short hnum,
 187				int dif)
 188{
 189	int score = -1;
 190
 191	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
 192			sk->sk_family == PF_INET6) {
 
 193		struct inet_sock *inet = inet_sk(sk);
 194
 195		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 196			return -1;
 197		score = 0;
 198		if (inet->inet_dport) {
 199			if (inet->inet_dport != sport)
 200				return -1;
 201			score++;
 202		}
 203		if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 204			if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 205				return -1;
 206			score++;
 207		}
 208		if (sk->sk_bound_dev_if) {
 209			if (sk->sk_bound_dev_if != dif)
 210				return -1;
 211			score++;
 212		}
 213	}
 214	return score;
 215}
 216
 217
 218/* called with read_rcu_lock() */
 219static struct sock *udp6_lib_lookup2(struct net *net,
 220		const struct in6_addr *saddr, __be16 sport,
 221		const struct in6_addr *daddr, unsigned int hnum, int dif,
 222		struct udp_hslot *hslot2, unsigned int slot2)
 223{
 224	struct sock *sk, *result;
 225	struct hlist_nulls_node *node;
 226	int score, badness, matches = 0, reuseport = 0;
 227	u32 hash = 0;
 228
 229begin:
 230	result = NULL;
 231	badness = -1;
 232	udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
 233		score = compute_score2(sk, net, saddr, sport,
 234				      daddr, hnum, dif);
 235		if (score > badness) {
 236			result = sk;
 237			badness = score;
 238			reuseport = sk->sk_reuseport;
 239			if (reuseport) {
 240				hash = udp6_ehashfn(net, daddr, hnum,
 241						    saddr, sport);
 242				matches = 1;
 243			} else if (score == SCORE2_MAX)
 244				goto exact_match;
 245		} else if (score == badness && reuseport) {
 246			matches++;
 247			if (((u64)hash * matches) >> 32 == 0)
 248				result = sk;
 249			hash = next_pseudo_random32(hash);
 250		}
 251	}
 252	/*
 253	 * if the nulls value we got at the end of this lookup is
 254	 * not the expected one, we must restart lookup.
 255	 * We probably met an item that was moved to another chain.
 256	 */
 257	if (get_nulls_value(node) != slot2)
 258		goto begin;
 259
 260	if (result) {
 261exact_match:
 262		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 263			result = NULL;
 264		else if (unlikely(compute_score2(result, net, saddr, sport,
 265				  daddr, hnum, dif) < badness)) {
 266			sock_put(result);
 267			goto begin;
 268		}
 269	}
 270	return result;
 271}
 272
 273struct sock *__udp6_lib_lookup(struct net *net,
 274				      const struct in6_addr *saddr, __be16 sport,
 275				      const struct in6_addr *daddr, __be16 dport,
 276				      int dif, struct udp_table *udptable)
 277{
 278	struct sock *sk, *result;
 279	struct hlist_nulls_node *node;
 280	unsigned short hnum = ntohs(dport);
 281	unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
 282	struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
 283	int score, badness, matches = 0, reuseport = 0;
 284	u32 hash = 0;
 285
 286	rcu_read_lock();
 287	if (hslot->count > 10) {
 288		hash2 = udp6_portaddr_hash(net, daddr, hnum);
 289		slot2 = hash2 & udptable->mask;
 290		hslot2 = &udptable->hash2[slot2];
 291		if (hslot->count < hslot2->count)
 292			goto begin;
 293
 294		result = udp6_lib_lookup2(net, saddr, sport,
 295					  daddr, hnum, dif,
 296					  hslot2, slot2);
 297		if (!result) {
 298			hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
 299			slot2 = hash2 & udptable->mask;
 300			hslot2 = &udptable->hash2[slot2];
 301			if (hslot->count < hslot2->count)
 302				goto begin;
 303
 304			result = udp6_lib_lookup2(net, saddr, sport,
 305						  &in6addr_any, hnum, dif,
 306						  hslot2, slot2);
 307		}
 308		rcu_read_unlock();
 309		return result;
 310	}
 311begin:
 312	result = NULL;
 313	badness = -1;
 314	sk_nulls_for_each_rcu(sk, node, &hslot->head) {
 315		score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
 316		if (score > badness) {
 317			result = sk;
 318			badness = score;
 319			reuseport = sk->sk_reuseport;
 320			if (reuseport) {
 321				hash = udp6_ehashfn(net, daddr, hnum,
 322						    saddr, sport);
 323				matches = 1;
 324			}
 325		} else if (score == badness && reuseport) {
 326			matches++;
 327			if (((u64)hash * matches) >> 32 == 0)
 328				result = sk;
 329			hash = next_pseudo_random32(hash);
 330		}
 331	}
 332	/*
 333	 * if the nulls value we got at the end of this lookup is
 334	 * not the expected one, we must restart lookup.
 335	 * We probably met an item that was moved to another chain.
 336	 */
 337	if (get_nulls_value(node) != slot)
 338		goto begin;
 339
 340	if (result) {
 341		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 342			result = NULL;
 343		else if (unlikely(compute_score(result, net, hnum, saddr, sport,
 344					daddr, dport, dif) < badness)) {
 345			sock_put(result);
 346			goto begin;
 347		}
 348	}
 349	rcu_read_unlock();
 350	return result;
 351}
 352EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
 353
 354static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 355					  __be16 sport, __be16 dport,
 356					  struct udp_table *udptable)
 357{
 358	struct sock *sk;
 359	const struct ipv6hdr *iph = ipv6_hdr(skb);
 360
 361	if (unlikely(sk = skb_steal_sock(skb)))
 362		return sk;
 363	return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
 364				 &iph->daddr, dport, inet6_iif(skb),
 365				 udptable);
 366}
 367
 368struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 369			     const struct in6_addr *daddr, __be16 dport, int dif)
 370{
 371	return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
 372}
 373EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 374
 375
 376/*
 377 * 	This should be easy, if there is something there we
 378 * 	return it, otherwise we block.
 379 */
 380
 381int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 382		  struct msghdr *msg, size_t len,
 383		  int noblock, int flags, int *addr_len)
 384{
 385	struct ipv6_pinfo *np = inet6_sk(sk);
 386	struct inet_sock *inet = inet_sk(sk);
 387	struct sk_buff *skb;
 388	unsigned int ulen, copied;
 389	int peeked, off = 0;
 390	int err;
 391	int is_udplite = IS_UDPLITE(sk);
 392	int is_udp4;
 393	bool slow;
 394
 
 
 
 395	if (flags & MSG_ERRQUEUE)
 396		return ipv6_recv_error(sk, msg, len, addr_len);
 397
 398	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 399		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 400
 401try_again:
 402	skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
 403				  &peeked, &off, &err);
 404	if (!skb)
 405		goto out;
 406
 407	ulen = skb->len - sizeof(struct udphdr);
 408	copied = len;
 409	if (copied > ulen)
 410		copied = ulen;
 411	else if (copied < ulen)
 412		msg->msg_flags |= MSG_TRUNC;
 413
 414	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 415
 416	/*
 417	 * If checksum is needed at all, try to do it while copying the
 418	 * data.  If the data is truncated, or if we only want a partial
 419	 * coverage checksum (UDP-Lite), do it before the copy.
 420	 */
 421
 422	if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
 423		if (udp_lib_checksum_complete(skb))
 424			goto csum_copy_err;
 425	}
 426
 427	if (skb_csum_unnecessary(skb))
 428		err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
 429					      msg->msg_iov, copied);
 430	else {
 431		err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 432		if (err == -EINVAL)
 433			goto csum_copy_err;
 434	}
 435	if (unlikely(err)) {
 436		trace_kfree_skb(skb, udpv6_recvmsg);
 437		if (!peeked) {
 438			atomic_inc(&sk->sk_drops);
 439			if (is_udp4)
 440				UDP_INC_STATS_USER(sock_net(sk),
 441						   UDP_MIB_INERRORS,
 442						   is_udplite);
 443			else
 444				UDP6_INC_STATS_USER(sock_net(sk),
 445						    UDP_MIB_INERRORS,
 446						    is_udplite);
 447		}
 448		goto out_free;
 449	}
 450	if (!peeked) {
 451		if (is_udp4)
 452			UDP_INC_STATS_USER(sock_net(sk),
 453					UDP_MIB_INDATAGRAMS, is_udplite);
 454		else
 455			UDP6_INC_STATS_USER(sock_net(sk),
 456					UDP_MIB_INDATAGRAMS, is_udplite);
 457	}
 458
 459	sock_recv_ts_and_drops(msg, sk, skb);
 460
 461	/* Copy the address. */
 462	if (msg->msg_name) {
 463		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 
 
 464		sin6->sin6_family = AF_INET6;
 465		sin6->sin6_port = udp_hdr(skb)->source;
 466		sin6->sin6_flowinfo = 0;
 
 467
 468		if (is_udp4) {
 469			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 470					       &sin6->sin6_addr);
 471			sin6->sin6_scope_id = 0;
 472		} else {
 473			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 474			sin6->sin6_scope_id =
 475				ipv6_iface_scope_id(&sin6->sin6_addr,
 476						    IP6CB(skb)->iif);
 477		}
 478		*addr_len = sizeof(*sin6);
 479	}
 480
 481	if (np->rxopt.all)
 482		ip6_datagram_recv_common_ctl(sk, msg, skb);
 483
 484	if (is_udp4) {
 485		if (inet->cmsg_flags)
 486			ip_cmsg_recv(msg, skb);
 487	} else {
 488		if (np->rxopt.all)
 489			ip6_datagram_recv_specific_ctl(sk, msg, skb);
 490	}
 491
 492	err = copied;
 493	if (flags & MSG_TRUNC)
 494		err = ulen;
 495
 496out_free:
 497	skb_free_datagram_locked(sk, skb);
 498out:
 499	return err;
 500
 501csum_copy_err:
 502	slow = lock_sock_fast(sk);
 503	if (!skb_kill_datagram(sk, skb, flags)) {
 504		if (is_udp4) {
 505			UDP_INC_STATS_USER(sock_net(sk),
 506					UDP_MIB_CSUMERRORS, is_udplite);
 507			UDP_INC_STATS_USER(sock_net(sk),
 508					UDP_MIB_INERRORS, is_udplite);
 509		} else {
 510			UDP6_INC_STATS_USER(sock_net(sk),
 511					UDP_MIB_CSUMERRORS, is_udplite);
 512			UDP6_INC_STATS_USER(sock_net(sk),
 513					UDP_MIB_INERRORS, is_udplite);
 514		}
 515	}
 516	unlock_sock_fast(sk, slow);
 517
 518	if (noblock)
 519		return -EAGAIN;
 520
 521	/* starting over for a new packet */
 522	msg->msg_flags &= ~MSG_TRUNC;
 523	goto try_again;
 524}
 525
 526void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 527		    u8 type, u8 code, int offset, __be32 info,
 528		    struct udp_table *udptable)
 529{
 530	struct ipv6_pinfo *np;
 531	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 532	const struct in6_addr *saddr = &hdr->saddr;
 533	const struct in6_addr *daddr = &hdr->daddr;
 534	struct udphdr *uh = (struct udphdr*)(skb->data+offset);
 535	struct sock *sk;
 536	int err;
 537
 538	sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
 539			       saddr, uh->source, inet6_iif(skb), udptable);
 540	if (sk == NULL)
 541		return;
 542
 543	if (type == ICMPV6_PKT_TOOBIG) {
 544		if (!ip6_sk_accept_pmtu(sk))
 545			goto out;
 546		ip6_sk_update_pmtu(skb, sk, info);
 547	}
 548	if (type == NDISC_REDIRECT) {
 549		ip6_sk_redirect(skb, sk);
 550		goto out;
 551	}
 552
 553	np = inet6_sk(sk);
 554
 555	if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
 556		goto out;
 557
 558	if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
 559		goto out;
 560
 561	if (np->recverr)
 562		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 563
 564	sk->sk_err = err;
 565	sk->sk_error_report(sk);
 566out:
 567	sock_put(sk);
 568}
 569
 570static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 571{
 572	int rc;
 573
 574	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 575		sock_rps_save_rxhash(sk, skb);
 576		sk_mark_napi_id(sk, skb);
 577	}
 578
 579	rc = sock_queue_rcv_skb(sk, skb);
 580	if (rc < 0) {
 581		int is_udplite = IS_UDPLITE(sk);
 582
 583		/* Note that an ENOMEM error is charged twice */
 584		if (rc == -ENOMEM)
 585			UDP6_INC_STATS_BH(sock_net(sk),
 586					UDP_MIB_RCVBUFERRORS, is_udplite);
 587		UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 588		kfree_skb(skb);
 589		return -1;
 590	}
 591	return 0;
 592}
 593
 594static __inline__ void udpv6_err(struct sk_buff *skb,
 595				 struct inet6_skb_parm *opt, u8 type,
 596				 u8 code, int offset, __be32 info     )
 597{
 598	__udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 599}
 600
 601static struct static_key udpv6_encap_needed __read_mostly;
 602void udpv6_encap_enable(void)
 603{
 604	if (!static_key_enabled(&udpv6_encap_needed))
 605		static_key_slow_inc(&udpv6_encap_needed);
 606}
 607EXPORT_SYMBOL(udpv6_encap_enable);
 608
 609int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 610{
 611	struct udp_sock *up = udp_sk(sk);
 612	int rc;
 613	int is_udplite = IS_UDPLITE(sk);
 614
 
 
 
 615	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 616		goto drop;
 617
 618	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
 619		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
 620
 621		/*
 622		 * This is an encapsulation socket so pass the skb to
 623		 * the socket's udp_encap_rcv() hook. Otherwise, just
 624		 * fall through and pass this up the UDP socket.
 625		 * up->encap_rcv() returns the following value:
 626		 * =0 if skb was successfully passed to the encap
 627		 *    handler or was discarded by it.
 628		 * >0 if skb should be passed on to UDP.
 629		 * <0 if skb should be resubmitted as proto -N
 630		 */
 631
 632		/* if we're overly short, let UDP handle it */
 633		encap_rcv = ACCESS_ONCE(up->encap_rcv);
 634		if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) {
 635			int ret;
 636
 637			ret = encap_rcv(sk, skb);
 638			if (ret <= 0) {
 639				UDP_INC_STATS_BH(sock_net(sk),
 640						 UDP_MIB_INDATAGRAMS,
 641						 is_udplite);
 642				return -ret;
 643			}
 644		}
 645
 646		/* FALLTHROUGH -- it's a UDP Packet */
 647	}
 648
 649	/*
 650	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 651	 */
 652	if ((is_udplite & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 653
 654		if (up->pcrlen == 0) {          /* full coverage was set  */
 655			LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
 656				" %d while full coverage %d requested\n",
 657				UDP_SKB_CB(skb)->cscov, skb->len);
 658			goto drop;
 659		}
 660		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 661			LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
 662						    "too small, need min %d\n",
 663				       UDP_SKB_CB(skb)->cscov, up->pcrlen);
 664			goto drop;
 665		}
 666	}
 667
 668	if (rcu_access_pointer(sk->sk_filter)) {
 669		if (udp_lib_checksum_complete(skb))
 670			goto csum_error;
 671	}
 672
 673	if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
 674		goto drop;
 675
 676	skb_dst_drop(skb);
 677
 678	bh_lock_sock(sk);
 679	rc = 0;
 680	if (!sock_owned_by_user(sk))
 681		rc = __udpv6_queue_rcv_skb(sk, skb);
 682	else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
 683		bh_unlock_sock(sk);
 684		goto drop;
 685	}
 686	bh_unlock_sock(sk);
 687
 688	return rc;
 689csum_error:
 690	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 691drop:
 
 
 692	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 693	atomic_inc(&sk->sk_drops);
 694	kfree_skb(skb);
 695	return -1;
 696}
 697
 698static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
 699				      __be16 loc_port, const struct in6_addr *loc_addr,
 700				      __be16 rmt_port, const struct in6_addr *rmt_addr,
 701				      int dif)
 702{
 703	struct hlist_nulls_node *node;
 704	struct sock *s = sk;
 705	unsigned short num = ntohs(loc_port);
 706
 707	sk_nulls_for_each_from(s, node) {
 708		struct inet_sock *inet = inet_sk(s);
 709
 710		if (!net_eq(sock_net(s), net))
 711			continue;
 712
 713		if (udp_sk(s)->udp_port_hash == num &&
 714		    s->sk_family == PF_INET6) {
 
 715			if (inet->inet_dport) {
 716				if (inet->inet_dport != rmt_port)
 717					continue;
 718			}
 719			if (!ipv6_addr_any(&sk->sk_v6_daddr) &&
 720			    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr))
 721				continue;
 722
 723			if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 724				continue;
 725
 726			if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
 727				if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))
 728					continue;
 729			}
 730			if (!inet6_mc_check(s, loc_addr, rmt_addr))
 731				continue;
 732			return s;
 733		}
 734	}
 735	return NULL;
 736}
 737
 738static void flush_stack(struct sock **stack, unsigned int count,
 739			struct sk_buff *skb, unsigned int final)
 740{
 741	struct sk_buff *skb1 = NULL;
 742	struct sock *sk;
 743	unsigned int i;
 744
 745	for (i = 0; i < count; i++) {
 
 
 746		sk = stack[i];
 747		if (likely(skb1 == NULL))
 748			skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
 749		if (!skb1) {
 750			atomic_inc(&sk->sk_drops);
 751			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
 752					  IS_UDPLITE(sk));
 753			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
 754					  IS_UDPLITE(sk));
 
 
 
 
 
 
 
 755		}
 756
 757		if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
 758			skb1 = NULL;
 
 
 
 759	}
 760	if (unlikely(skb1))
 761		kfree_skb(skb1);
 762}
 763/*
 764 * Note: called only from the BH handler context,
 765 * so we don't need to lock the hashes.
 766 */
 767static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 768		const struct in6_addr *saddr, const struct in6_addr *daddr,
 769		struct udp_table *udptable)
 770{
 771	struct sock *sk, *stack[256 / sizeof(struct sock *)];
 772	const struct udphdr *uh = udp_hdr(skb);
 773	struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
 774	int dif;
 775	unsigned int i, count = 0;
 776
 777	spin_lock(&hslot->lock);
 778	sk = sk_nulls_head(&hslot->head);
 779	dif = inet6_iif(skb);
 780	sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
 781	while (sk) {
 782		stack[count++] = sk;
 783		sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
 784				       uh->source, saddr, dif);
 785		if (unlikely(count == ARRAY_SIZE(stack))) {
 786			if (!sk)
 787				break;
 788			flush_stack(stack, count, skb, ~0);
 789			count = 0;
 790		}
 791	}
 792	/*
 793	 * before releasing the lock, we must take reference on sockets
 794	 */
 795	for (i = 0; i < count; i++)
 796		sock_hold(stack[i]);
 797
 798	spin_unlock(&hslot->lock);
 799
 800	if (count) {
 801		flush_stack(stack, count, skb, count - 1);
 802
 803		for (i = 0; i < count; i++)
 804			sock_put(stack[i]);
 805	} else {
 806		kfree_skb(skb);
 807	}
 808	return 0;
 809}
 810
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 811int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 812		   int proto)
 813{
 814	struct net *net = dev_net(skb->dev);
 815	struct sock *sk;
 816	struct udphdr *uh;
 817	const struct in6_addr *saddr, *daddr;
 818	u32 ulen = 0;
 819
 820	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 821		goto discard;
 822
 823	saddr = &ipv6_hdr(skb)->saddr;
 824	daddr = &ipv6_hdr(skb)->daddr;
 825	uh = udp_hdr(skb);
 826
 827	ulen = ntohs(uh->len);
 828	if (ulen > skb->len)
 829		goto short_packet;
 830
 831	if (proto == IPPROTO_UDP) {
 832		/* UDP validates ulen. */
 833
 834		/* Check for jumbo payload */
 835		if (ulen == 0)
 836			ulen = skb->len;
 837
 838		if (ulen < sizeof(*uh))
 839			goto short_packet;
 840
 841		if (ulen < skb->len) {
 842			if (pskb_trim_rcsum(skb, ulen))
 843				goto short_packet;
 844			saddr = &ipv6_hdr(skb)->saddr;
 845			daddr = &ipv6_hdr(skb)->daddr;
 846			uh = udp_hdr(skb);
 847		}
 848	}
 849
 850	if (udp6_csum_init(skb, uh, proto))
 851		goto csum_error;
 852
 853	/*
 854	 *	Multicast receive code
 855	 */
 856	if (ipv6_addr_is_multicast(daddr))
 857		return __udp6_lib_mcast_deliver(net, skb,
 858				saddr, daddr, udptable);
 859
 860	/* Unicast */
 861
 862	/*
 863	 * check socket cache ... must talk to Alan about his plans
 864	 * for sock caches... i'll skip this for now.
 865	 */
 866	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
 867	if (sk != NULL) {
 868		int ret;
 869
 870		ret = udpv6_queue_rcv_skb(sk, skb);
 871		sock_put(sk);
 
 
 
 
 
 
 872
 873		/* a return value > 0 means to resubmit the input, but
 874		 * it wants the return to be -protocol, or 0
 875		 */
 876		if (ret > 0)
 877			return -ret;
 878
 
 879		return 0;
 880	}
 881
 882	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 
 
 
 883		goto discard;
 884
 885	if (udp_lib_checksum_complete(skb))
 886		goto csum_error;
 887
 888	UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
 889	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 890
 891	kfree_skb(skb);
 
 
 
 
 892	return 0;
 893
 894short_packet:
 895	LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
 896		       proto == IPPROTO_UDPLITE ? "-Lite" : "",
 897		       saddr,
 898		       ntohs(uh->source),
 899		       ulen,
 900		       skb->len,
 901		       daddr,
 902		       ntohs(uh->dest));
 903	goto discard;
 904csum_error:
 905	UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
 906discard:
 907	UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
 908	kfree_skb(skb);
 909	return 0;
 910}
 911
 912static __inline__ int udpv6_rcv(struct sk_buff *skb)
 913{
 914	return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
 915}
 916
 917/*
 918 * Throw away all pending data and cancel the corking. Socket is locked.
 919 */
 920static void udp_v6_flush_pending_frames(struct sock *sk)
 921{
 922	struct udp_sock *up = udp_sk(sk);
 923
 924	if (up->pending == AF_INET)
 925		udp_flush_pending_frames(sk);
 926	else if (up->pending) {
 927		up->len = 0;
 928		up->pending = 0;
 929		ip6_flush_pending_frames(sk);
 930	}
 931}
 932
 933/**
 934 * 	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
 935 * 	@sk: 	socket we are sending on
 936 * 	@skb: 	sk_buff containing the filled-in UDP header
 937 * 	        (checksum field must be zeroed out)
 938 */
 939static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
 940				 const struct in6_addr *saddr,
 941				 const struct in6_addr *daddr, int len)
 942{
 943	unsigned int offset;
 944	struct udphdr *uh = udp_hdr(skb);
 945	__wsum csum = 0;
 946
 947	if (skb_queue_len(&sk->sk_write_queue) == 1) {
 948		/* Only one fragment on the socket.  */
 949		skb->csum_start = skb_transport_header(skb) - skb->head;
 950		skb->csum_offset = offsetof(struct udphdr, check);
 951		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
 952	} else {
 953		/*
 954		 * HW-checksum won't work as there are two or more
 955		 * fragments on the socket so that all csums of sk_buffs
 956		 * should be together
 957		 */
 958		offset = skb_transport_offset(skb);
 959		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
 960
 961		skb->ip_summed = CHECKSUM_NONE;
 962
 963		skb_queue_walk(&sk->sk_write_queue, skb) {
 964			csum = csum_add(csum, skb->csum);
 965		}
 966
 967		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
 968					    csum);
 969		if (uh->check == 0)
 970			uh->check = CSUM_MANGLED_0;
 971	}
 972}
 973
 974/*
 975 *	Sending
 976 */
 977
 978static int udp_v6_push_pending_frames(struct sock *sk)
 979{
 980	struct sk_buff *skb;
 981	struct udphdr *uh;
 982	struct udp_sock  *up = udp_sk(sk);
 983	struct inet_sock *inet = inet_sk(sk);
 984	struct flowi6 *fl6;
 985	int err = 0;
 986	int is_udplite = IS_UDPLITE(sk);
 987	__wsum csum = 0;
 988
 989	if (up->pending == AF_INET)
 990		return udp_push_pending_frames(sk);
 991
 992	fl6 = &inet->cork.fl.u.ip6;
 993
 994	/* Grab the skbuff where UDP header space exists. */
 995	if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 996		goto out;
 997
 998	/*
 999	 * Create a UDP header
1000	 */
1001	uh = udp_hdr(skb);
1002	uh->source = fl6->fl6_sport;
1003	uh->dest = fl6->fl6_dport;
1004	uh->len = htons(up->len);
1005	uh->check = 0;
1006
1007	if (is_udplite)
1008		csum = udplite_csum_outgoing(sk, skb);
1009	else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1010		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
1011				     up->len);
1012		goto send;
1013	} else
1014		csum = udp_csum_outgoing(sk, skb);
1015
1016	/* add protocol-dependent pseudo-header */
1017	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1018				    up->len, fl6->flowi6_proto, csum);
1019	if (uh->check == 0)
1020		uh->check = CSUM_MANGLED_0;
1021
1022send:
1023	err = ip6_push_pending_frames(sk);
1024	if (err) {
1025		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1026			UDP6_INC_STATS_USER(sock_net(sk),
1027					    UDP_MIB_SNDBUFERRORS, is_udplite);
1028			err = 0;
1029		}
1030	} else
1031		UDP6_INC_STATS_USER(sock_net(sk),
1032				    UDP_MIB_OUTDATAGRAMS, is_udplite);
1033out:
1034	up->len = 0;
1035	up->pending = 0;
1036	return err;
1037}
1038
1039int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
1040		  struct msghdr *msg, size_t len)
1041{
1042	struct ipv6_txoptions opt_space;
1043	struct udp_sock *up = udp_sk(sk);
1044	struct inet_sock *inet = inet_sk(sk);
1045	struct ipv6_pinfo *np = inet6_sk(sk);
1046	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1047	struct in6_addr *daddr, *final_p, final;
1048	struct ipv6_txoptions *opt = NULL;
1049	struct ip6_flowlabel *flowlabel = NULL;
1050	struct flowi6 fl6;
1051	struct dst_entry *dst;
1052	int addr_len = msg->msg_namelen;
1053	int ulen = len;
1054	int hlimit = -1;
1055	int tclass = -1;
1056	int dontfrag = -1;
1057	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1058	int err;
1059	int connected = 0;
1060	int is_udplite = IS_UDPLITE(sk);
1061	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1062
1063	/* destination address check */
1064	if (sin6) {
1065		if (addr_len < offsetof(struct sockaddr, sa_data))
1066			return -EINVAL;
1067
1068		switch (sin6->sin6_family) {
1069		case AF_INET6:
1070			if (addr_len < SIN6_LEN_RFC2133)
1071				return -EINVAL;
1072			daddr = &sin6->sin6_addr;
1073			break;
1074		case AF_INET:
1075			goto do_udp_sendmsg;
1076		case AF_UNSPEC:
1077			msg->msg_name = sin6 = NULL;
1078			msg->msg_namelen = addr_len = 0;
1079			daddr = NULL;
1080			break;
1081		default:
1082			return -EINVAL;
1083		}
1084	} else if (!up->pending) {
1085		if (sk->sk_state != TCP_ESTABLISHED)
1086			return -EDESTADDRREQ;
1087		daddr = &sk->sk_v6_daddr;
1088	} else
1089		daddr = NULL;
1090
1091	if (daddr) {
1092		if (ipv6_addr_v4mapped(daddr)) {
1093			struct sockaddr_in sin;
1094			sin.sin_family = AF_INET;
1095			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1096			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1097			msg->msg_name = &sin;
1098			msg->msg_namelen = sizeof(sin);
1099do_udp_sendmsg:
1100			if (__ipv6_only_sock(sk))
1101				return -ENETUNREACH;
1102			return udp_sendmsg(iocb, sk, msg, len);
1103		}
1104	}
1105
1106	if (up->pending == AF_INET)
1107		return udp_sendmsg(iocb, sk, msg, len);
1108
1109	/* Rough check on arithmetic overflow,
1110	   better check is made in ip6_append_data().
1111	   */
1112	if (len > INT_MAX - sizeof(struct udphdr))
1113		return -EMSGSIZE;
1114
1115	if (up->pending) {
1116		/*
1117		 * There are pending frames.
1118		 * The socket lock must be held while it's corked.
1119		 */
1120		lock_sock(sk);
1121		if (likely(up->pending)) {
1122			if (unlikely(up->pending != AF_INET6)) {
1123				release_sock(sk);
1124				return -EAFNOSUPPORT;
1125			}
1126			dst = NULL;
1127			goto do_append_data;
1128		}
1129		release_sock(sk);
1130	}
1131	ulen += sizeof(struct udphdr);
1132
1133	memset(&fl6, 0, sizeof(fl6));
1134
1135	if (sin6) {
1136		if (sin6->sin6_port == 0)
1137			return -EINVAL;
1138
1139		fl6.fl6_dport = sin6->sin6_port;
1140		daddr = &sin6->sin6_addr;
1141
1142		if (np->sndflow) {
1143			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1144			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1145				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1146				if (flowlabel == NULL)
1147					return -EINVAL;
 
1148			}
1149		}
1150
1151		/*
1152		 * Otherwise it will be difficult to maintain
1153		 * sk->sk_dst_cache.
1154		 */
1155		if (sk->sk_state == TCP_ESTABLISHED &&
1156		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1157			daddr = &sk->sk_v6_daddr;
1158
1159		if (addr_len >= sizeof(struct sockaddr_in6) &&
1160		    sin6->sin6_scope_id &&
1161		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1162			fl6.flowi6_oif = sin6->sin6_scope_id;
1163	} else {
1164		if (sk->sk_state != TCP_ESTABLISHED)
1165			return -EDESTADDRREQ;
1166
1167		fl6.fl6_dport = inet->inet_dport;
1168		daddr = &sk->sk_v6_daddr;
1169		fl6.flowlabel = np->flow_label;
1170		connected = 1;
1171	}
1172
1173	if (!fl6.flowi6_oif)
1174		fl6.flowi6_oif = sk->sk_bound_dev_if;
1175
1176	if (!fl6.flowi6_oif)
1177		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1178
1179	fl6.flowi6_mark = sk->sk_mark;
1180
1181	if (msg->msg_controllen) {
1182		opt = &opt_space;
1183		memset(opt, 0, sizeof(struct ipv6_txoptions));
1184		opt->tot_len = sizeof(*opt);
1185
1186		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1187					    &hlimit, &tclass, &dontfrag);
1188		if (err < 0) {
1189			fl6_sock_release(flowlabel);
1190			return err;
1191		}
1192		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1193			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1194			if (flowlabel == NULL)
1195				return -EINVAL;
1196		}
1197		if (!(opt->opt_nflen|opt->opt_flen))
1198			opt = NULL;
1199		connected = 0;
1200	}
1201	if (opt == NULL)
1202		opt = np->opt;
1203	if (flowlabel)
1204		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1205	opt = ipv6_fixup_options(&opt_space, opt);
1206
1207	fl6.flowi6_proto = sk->sk_protocol;
1208	if (!ipv6_addr_any(daddr))
1209		fl6.daddr = *daddr;
1210	else
1211		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1212	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1213		fl6.saddr = np->saddr;
1214	fl6.fl6_sport = inet->inet_sport;
1215
1216	final_p = fl6_update_dst(&fl6, opt, &final);
1217	if (final_p)
1218		connected = 0;
1219
1220	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1221		fl6.flowi6_oif = np->mcast_oif;
1222		connected = 0;
1223	} else if (!fl6.flowi6_oif)
1224		fl6.flowi6_oif = np->ucast_oif;
1225
1226	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1227
1228	dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
1229	if (IS_ERR(dst)) {
1230		err = PTR_ERR(dst);
1231		dst = NULL;
1232		goto out;
1233	}
1234
1235	if (hlimit < 0) {
1236		if (ipv6_addr_is_multicast(&fl6.daddr))
1237			hlimit = np->mcast_hops;
1238		else
1239			hlimit = np->hop_limit;
1240		if (hlimit < 0)
1241			hlimit = ip6_dst_hoplimit(dst);
1242	}
1243
1244	if (tclass < 0)
1245		tclass = np->tclass;
1246
 
 
 
1247	if (msg->msg_flags&MSG_CONFIRM)
1248		goto do_confirm;
1249back_from_confirm:
1250
1251	lock_sock(sk);
1252	if (unlikely(up->pending)) {
1253		/* The socket is already corked while preparing it. */
1254		/* ... which is an evident application bug. --ANK */
1255		release_sock(sk);
1256
1257		LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1258		err = -EINVAL;
1259		goto out;
1260	}
1261
1262	up->pending = AF_INET6;
1263
1264do_append_data:
1265	if (dontfrag < 0)
1266		dontfrag = np->dontfrag;
1267	up->len += ulen;
1268	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1269	err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1270		sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1271		(struct rt6_info*)dst,
1272		corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1273	if (err)
1274		udp_v6_flush_pending_frames(sk);
1275	else if (!corkreq)
1276		err = udp_v6_push_pending_frames(sk);
1277	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1278		up->pending = 0;
1279
1280	if (dst) {
1281		if (connected) {
1282			ip6_dst_store(sk, dst,
1283				      ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
1284				      &sk->sk_v6_daddr : NULL,
1285#ifdef CONFIG_IPV6_SUBTREES
1286				      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1287				      &np->saddr :
1288#endif
1289				      NULL);
1290		} else {
1291			dst_release(dst);
1292		}
1293		dst = NULL;
1294	}
1295
1296	if (err > 0)
1297		err = np->recverr ? net_xmit_errno(err) : 0;
1298	release_sock(sk);
1299out:
1300	dst_release(dst);
1301	fl6_sock_release(flowlabel);
1302	if (!err)
1303		return len;
1304	/*
1305	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1306	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1307	 * we don't have a good statistic (IpOutDiscards but it can be too many
1308	 * things).  We could add another new stat but at least for now that
1309	 * seems like overkill.
1310	 */
1311	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1312		UDP6_INC_STATS_USER(sock_net(sk),
1313				UDP_MIB_SNDBUFERRORS, is_udplite);
1314	}
1315	return err;
1316
1317do_confirm:
1318	dst_confirm(dst);
1319	if (!(msg->msg_flags&MSG_PROBE) || len)
1320		goto back_from_confirm;
1321	err = 0;
1322	goto out;
1323}
1324
1325void udpv6_destroy_sock(struct sock *sk)
1326{
1327	struct udp_sock *up = udp_sk(sk);
1328	lock_sock(sk);
1329	udp_v6_flush_pending_frames(sk);
1330	release_sock(sk);
1331
1332	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1333		void (*encap_destroy)(struct sock *sk);
1334		encap_destroy = ACCESS_ONCE(up->encap_destroy);
1335		if (encap_destroy)
1336			encap_destroy(sk);
1337	}
1338
1339	inet6_destroy_sock(sk);
1340}
1341
1342/*
1343 *	Socket option code for UDP
1344 */
1345int udpv6_setsockopt(struct sock *sk, int level, int optname,
1346		     char __user *optval, unsigned int optlen)
1347{
1348	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1349		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1350					  udp_v6_push_pending_frames);
1351	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1352}
1353
1354#ifdef CONFIG_COMPAT
1355int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1356			    char __user *optval, unsigned int optlen)
1357{
1358	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1359		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1360					  udp_v6_push_pending_frames);
1361	return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1362}
1363#endif
1364
1365int udpv6_getsockopt(struct sock *sk, int level, int optname,
1366		     char __user *optval, int __user *optlen)
1367{
1368	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1369		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1370	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1371}
1372
1373#ifdef CONFIG_COMPAT
1374int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1375			    char __user *optval, int __user *optlen)
1376{
1377	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1378		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1379	return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1380}
1381#endif
1382
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1383static const struct inet6_protocol udpv6_protocol = {
1384	.handler	=	udpv6_rcv,
1385	.err_handler	=	udpv6_err,
 
 
1386	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1387};
1388
1389/* ------------------------------------------------------------------------ */
1390#ifdef CONFIG_PROC_FS
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1391int udp6_seq_show(struct seq_file *seq, void *v)
1392{
1393	if (v == SEQ_START_TOKEN) {
1394		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1395	} else {
1396		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1397		struct inet_sock *inet = inet_sk(v);
1398		__u16 srcp = ntohs(inet->inet_sport);
1399		__u16 destp = ntohs(inet->inet_dport);
1400		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
1401	}
1402	return 0;
1403}
1404
1405static const struct file_operations udp6_afinfo_seq_fops = {
1406	.owner    = THIS_MODULE,
1407	.open     = udp_seq_open,
1408	.read     = seq_read,
1409	.llseek   = seq_lseek,
1410	.release  = seq_release_net
1411};
1412
1413static struct udp_seq_afinfo udp6_seq_afinfo = {
1414	.name		= "udp6",
1415	.family		= AF_INET6,
1416	.udp_table	= &udp_table,
1417	.seq_fops	= &udp6_afinfo_seq_fops,
 
 
1418	.seq_ops	= {
1419		.show		= udp6_seq_show,
1420	},
1421};
1422
1423int __net_init udp6_proc_init(struct net *net)
1424{
1425	return udp_proc_register(net, &udp6_seq_afinfo);
1426}
1427
1428void udp6_proc_exit(struct net *net) {
1429	udp_proc_unregister(net, &udp6_seq_afinfo);
1430}
1431#endif /* CONFIG_PROC_FS */
1432
1433void udp_v6_clear_sk(struct sock *sk, int size)
1434{
1435	struct inet_sock *inet = inet_sk(sk);
1436
1437	/* we do not want to clear pinet6 field, because of RCU lookups */
1438	sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6));
1439
1440	size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
1441	memset(&inet->pinet6 + 1, 0, size);
1442}
1443
1444/* ------------------------------------------------------------------------ */
1445
1446struct proto udpv6_prot = {
1447	.name		   = "UDPv6",
1448	.owner		   = THIS_MODULE,
1449	.close		   = udp_lib_close,
1450	.connect	   = ip6_datagram_connect,
1451	.disconnect	   = udp_disconnect,
1452	.ioctl		   = udp_ioctl,
1453	.destroy	   = udpv6_destroy_sock,
1454	.setsockopt	   = udpv6_setsockopt,
1455	.getsockopt	   = udpv6_getsockopt,
1456	.sendmsg	   = udpv6_sendmsg,
1457	.recvmsg	   = udpv6_recvmsg,
1458	.backlog_rcv	   = __udpv6_queue_rcv_skb,
1459	.hash		   = udp_lib_hash,
1460	.unhash		   = udp_lib_unhash,
1461	.rehash		   = udp_v6_rehash,
1462	.get_port	   = udp_v6_get_port,
1463	.memory_allocated  = &udp_memory_allocated,
1464	.sysctl_mem	   = sysctl_udp_mem,
1465	.sysctl_wmem	   = &sysctl_udp_wmem_min,
1466	.sysctl_rmem	   = &sysctl_udp_rmem_min,
1467	.obj_size	   = sizeof(struct udp6_sock),
1468	.slab_flags	   = SLAB_DESTROY_BY_RCU,
1469	.h.udp_table	   = &udp_table,
1470#ifdef CONFIG_COMPAT
1471	.compat_setsockopt = compat_udpv6_setsockopt,
1472	.compat_getsockopt = compat_udpv6_getsockopt,
1473#endif
1474	.clear_sk	   = udp_v6_clear_sk,
1475};
1476
1477static struct inet_protosw udpv6_protosw = {
1478	.type =      SOCK_DGRAM,
1479	.protocol =  IPPROTO_UDP,
1480	.prot =      &udpv6_prot,
1481	.ops =       &inet6_dgram_ops,
1482	.no_check =  UDP_CSUM_DEFAULT,
1483	.flags =     INET_PROTOSW_PERMANENT,
1484};
1485
1486
1487int __init udpv6_init(void)
1488{
1489	int ret;
1490
1491	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1492	if (ret)
1493		goto out;
1494
1495	ret = inet6_register_protosw(&udpv6_protosw);
1496	if (ret)
1497		goto out_udpv6_protocol;
1498out:
1499	return ret;
1500
1501out_udpv6_protocol:
1502	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1503	goto out;
1504}
1505
1506void udpv6_exit(void)
1507{
1508	inet6_unregister_protosw(&udpv6_protosw);
1509	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1510}