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v5.9
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	UDP over IPv6
   4 *	Linux INET6 implementation
   5 *
   6 *	Authors:
   7 *	Pedro Roque		<roque@di.fc.ul.pt>
   8 *
   9 *	Based on linux/ipv4/udp.c
  10 *
  11 *	Fixes:
  12 *	Hideaki YOSHIFUJI	:	sin6_scope_id support
  13 *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
  14 *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
  15 *					a single port at the same time.
  16 *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
  17 *      YOSHIFUJI Hideaki @USAGI:	convert /proc/net/udp6 to seq_file.
 
 
 
 
 
  18 */
  19
  20#include <linux/errno.h>
  21#include <linux/types.h>
  22#include <linux/socket.h>
  23#include <linux/sockios.h>
  24#include <linux/net.h>
  25#include <linux/in6.h>
  26#include <linux/netdevice.h>
  27#include <linux/if_arp.h>
  28#include <linux/ipv6.h>
  29#include <linux/icmpv6.h>
  30#include <linux/init.h>
  31#include <linux/module.h>
  32#include <linux/skbuff.h>
  33#include <linux/slab.h>
  34#include <linux/uaccess.h>
  35#include <linux/indirect_call_wrapper.h>
  36
  37#include <net/addrconf.h>
  38#include <net/ndisc.h>
  39#include <net/protocol.h>
  40#include <net/transp_v6.h>
  41#include <net/ip6_route.h>
  42#include <net/raw.h>
  43#include <net/tcp_states.h>
  44#include <net/ip6_checksum.h>
  45#include <net/ip6_tunnel.h>
  46#include <net/xfrm.h>
  47#include <net/inet_hashtables.h>
  48#include <net/inet6_hashtables.h>
  49#include <net/busy_poll.h>
  50#include <net/sock_reuseport.h>
  51
  52#include <linux/proc_fs.h>
  53#include <linux/seq_file.h>
  54#include <trace/events/skb.h>
  55#include "udp_impl.h"
  56
  57static u32 udp6_ehashfn(const struct net *net,
  58			const struct in6_addr *laddr,
  59			const u16 lport,
  60			const struct in6_addr *faddr,
  61			const __be16 fport)
  62{
  63	static u32 udp6_ehash_secret __read_mostly;
  64	static u32 udp_ipv6_hash_secret __read_mostly;
  65
  66	u32 lhash, fhash;
  67
  68	net_get_random_once(&udp6_ehash_secret,
  69			    sizeof(udp6_ehash_secret));
  70	net_get_random_once(&udp_ipv6_hash_secret,
  71			    sizeof(udp_ipv6_hash_secret));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  72
  73	lhash = (__force u32)laddr->s6_addr32[3];
  74	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
 
 
 
 
 
 
 
 
 
 
  75
  76	return __inet6_ehashfn(lhash, lport, fhash, fport,
  77			       udp_ipv6_hash_secret + net_hash_mix(net));
  78}
  79
 
  80int udp_v6_get_port(struct sock *sk, unsigned short snum)
  81{
  82	unsigned int hash2_nulladdr =
  83		ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
  84	unsigned int hash2_partial =
  85		ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
  86
  87	/* precompute partial secondary hash */
  88	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
  89	return udp_lib_get_port(sk, snum, hash2_nulladdr);
  90}
  91
  92void udp_v6_rehash(struct sock *sk)
  93{
  94	u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
  95					  &sk->sk_v6_rcv_saddr,
  96					  inet_sk(sk)->inet_num);
  97
  98	udp_lib_rehash(sk, new_hash);
  99}
 100
 101static int compute_score(struct sock *sk, struct net *net,
 102			 const struct in6_addr *saddr, __be16 sport,
 103			 const struct in6_addr *daddr, unsigned short hnum,
 104			 int dif, int sdif)
 105{
 106	int score;
 107	struct inet_sock *inet;
 108	bool dev_match;
 109
 110	if (!net_eq(sock_net(sk), net) ||
 111	    udp_sk(sk)->udp_port_hash != hnum ||
 112	    sk->sk_family != PF_INET6)
 113		return -1;
 114
 115	if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 116		return -1;
 117
 118	score = 0;
 119	inet = inet_sk(sk);
 120
 121	if (inet->inet_dport) {
 122		if (inet->inet_dport != sport)
 123			return -1;
 124		score++;
 125	}
 126
 127	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 128		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 129			return -1;
 130		score++;
 
 
 
 
 131	}
 132
 133	dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif);
 134	if (!dev_match)
 135		return -1;
 136	score++;
 137
 138	if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
 139		score++;
 140
 141	return score;
 142}
 143
 144static struct sock *lookup_reuseport(struct net *net, struct sock *sk,
 145				     struct sk_buff *skb,
 146				     const struct in6_addr *saddr,
 147				     __be16 sport,
 148				     const struct in6_addr *daddr,
 149				     unsigned int hnum)
 150{
 151	struct sock *reuse_sk = NULL;
 152	u32 hash;
 
 
 
 153
 154	if (sk->sk_reuseport && sk->sk_state != TCP_ESTABLISHED) {
 155		hash = udp6_ehashfn(net, daddr, hnum, saddr, sport);
 156		reuse_sk = reuseport_select_sock(sk, hash, skb,
 157						 sizeof(struct udphdr));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 158	}
 159	return reuse_sk;
 160}
 161
 162/* called with rcu_read_lock() */
 
 163static struct sock *udp6_lib_lookup2(struct net *net,
 164		const struct in6_addr *saddr, __be16 sport,
 165		const struct in6_addr *daddr, unsigned int hnum,
 166		int dif, int sdif, struct udp_hslot *hslot2,
 167		struct sk_buff *skb)
 168{
 169	struct sock *sk, *result;
 
 170	int score, badness;
 171
 
 172	result = NULL;
 173	badness = -1;
 174	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
 175		score = compute_score(sk, net, saddr, sport,
 176				      daddr, hnum, dif, sdif);
 177		if (score > badness) {
 178			result = lookup_reuseport(net, sk, skb,
 179						  saddr, sport, daddr, hnum);
 180			/* Fall back to scoring if group has connections */
 181			if (result && !reuseport_has_conns(sk, false))
 182				return result;
 183
 184			result = result ? : sk;
 185			badness = score;
 
 
 186		}
 187	}
 188	return result;
 189}
 190
 191static inline struct sock *udp6_lookup_run_bpf(struct net *net,
 192					       struct udp_table *udptable,
 193					       struct sk_buff *skb,
 194					       const struct in6_addr *saddr,
 195					       __be16 sport,
 196					       const struct in6_addr *daddr,
 197					       u16 hnum)
 198{
 199	struct sock *sk, *reuse_sk;
 200	bool no_reuseport;
 201
 202	if (udptable != &udp_table)
 203		return NULL; /* only UDP is supported */
 204
 205	no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP,
 206					    saddr, sport, daddr, hnum, &sk);
 207	if (no_reuseport || IS_ERR_OR_NULL(sk))
 208		return sk;
 209
 210	reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
 211	if (reuse_sk)
 212		sk = reuse_sk;
 213	return sk;
 
 
 
 
 
 
 
 214}
 215
 216/* rcu_read_lock() must be held */
 217struct sock *__udp6_lib_lookup(struct net *net,
 218			       const struct in6_addr *saddr, __be16 sport,
 219			       const struct in6_addr *daddr, __be16 dport,
 220			       int dif, int sdif, struct udp_table *udptable,
 221			       struct sk_buff *skb)
 222{
 
 
 223	unsigned short hnum = ntohs(dport);
 224	unsigned int hash2, slot2;
 225	struct udp_hslot *hslot2;
 226	struct sock *result, *sk;
 227
 228	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
 229	slot2 = hash2 & udptable->mask;
 230	hslot2 = &udptable->hash2[slot2];
 231
 232	/* Lookup connected or non-wildcard sockets */
 233	result = udp6_lib_lookup2(net, saddr, sport,
 234				  daddr, hnum, dif, sdif,
 235				  hslot2, skb);
 236	if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
 237		goto done;
 238
 239	/* Lookup redirect from BPF */
 240	if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
 241		sk = udp6_lookup_run_bpf(net, udptable, skb,
 242					 saddr, sport, daddr, hnum);
 243		if (sk) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 244			result = sk;
 245			goto done;
 246		}
 247	}
 
 
 
 
 
 
 
 248
 249	/* Got non-wildcard socket or error on first lookup */
 250	if (result)
 251		goto done;
 252
 253	/* Lookup wildcard sockets */
 254	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
 255	slot2 = hash2 & udptable->mask;
 256	hslot2 = &udptable->hash2[slot2];
 257
 258	result = udp6_lib_lookup2(net, saddr, sport,
 259				  &in6addr_any, hnum, dif, sdif,
 260				  hslot2, skb);
 261done:
 262	if (IS_ERR(result))
 263		return NULL;
 264	return result;
 265}
 266EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
 267
 268static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 269					  __be16 sport, __be16 dport,
 270					  struct udp_table *udptable)
 271{
 
 272	const struct ipv6hdr *iph = ipv6_hdr(skb);
 273
 274	return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
 275				 &iph->daddr, dport, inet6_iif(skb),
 276				 inet6_sdif(skb), udptable, skb);
 277}
 278
 279struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
 280				 __be16 sport, __be16 dport)
 281{
 282	const struct ipv6hdr *iph = ipv6_hdr(skb);
 283
 284	return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
 285				 &iph->daddr, dport, inet6_iif(skb),
 286				 inet6_sdif(skb), &udp_table, NULL);
 287}
 288EXPORT_SYMBOL_GPL(udp6_lib_lookup_skb);
 289
 290/* Must be called under rcu_read_lock().
 291 * Does increment socket refcount.
 292 */
 293#if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
 294struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 295			     const struct in6_addr *daddr, __be16 dport, int dif)
 296{
 297	struct sock *sk;
 298
 299	sk =  __udp6_lib_lookup(net, saddr, sport, daddr, dport,
 300				dif, 0, &udp_table, NULL);
 301	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
 302		sk = NULL;
 303	return sk;
 304}
 305EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 306#endif
 307
 308/* do not use the scratch area len for jumbogram: their length execeeds the
 309 * scratch area space; note that the IP6CB flags is still in the first
 310 * cacheline, so checking for jumbograms is cheap
 311 */
 312static int udp6_skb_len(struct sk_buff *skb)
 313{
 314	return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
 315}
 316
 317/*
 318 *	This should be easy, if there is something there we
 319 *	return it, otherwise we block.
 320 */
 321
 322int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 
 323		  int noblock, int flags, int *addr_len)
 324{
 325	struct ipv6_pinfo *np = inet6_sk(sk);
 326	struct inet_sock *inet = inet_sk(sk);
 327	struct sk_buff *skb;
 328	unsigned int ulen, copied;
 329	int off, err, peeking = flags & MSG_PEEK;
 
 330	int is_udplite = IS_UDPLITE(sk);
 331	struct udp_mib __percpu *mib;
 332	bool checksum_valid = false;
 333	int is_udp4;
 
 
 
 
 334
 335	if (flags & MSG_ERRQUEUE)
 336		return ipv6_recv_error(sk, msg, len, addr_len);
 337
 338	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 339		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 340
 341try_again:
 342	off = sk_peek_offset(sk, flags);
 343	skb = __skb_recv_udp(sk, flags, noblock, &off, &err);
 344	if (!skb)
 345		return err;
 346
 347	ulen = udp6_skb_len(skb);
 348	copied = len;
 349	if (copied > ulen - off)
 350		copied = ulen - off;
 351	else if (copied < ulen)
 352		msg->msg_flags |= MSG_TRUNC;
 353
 354	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 355	mib = __UDPX_MIB(sk, is_udp4);
 356
 357	/*
 358	 * If checksum is needed at all, try to do it while copying the
 359	 * data.  If the data is truncated, or if we only want a partial
 360	 * coverage checksum (UDP-Lite), do it before the copy.
 361	 */
 362
 363	if (copied < ulen || peeking ||
 364	    (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
 365		checksum_valid = udp_skb_csum_unnecessary(skb) ||
 366				!__udp_lib_checksum_complete(skb);
 367		if (!checksum_valid)
 368			goto csum_copy_err;
 369	}
 370
 371	if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
 372		if (udp_skb_is_linear(skb))
 373			err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
 374		else
 375			err = skb_copy_datagram_msg(skb, off, msg, copied);
 376	} else {
 377		err = skb_copy_and_csum_datagram_msg(skb, off, msg);
 378		if (err == -EINVAL)
 379			goto csum_copy_err;
 380	}
 381	if (unlikely(err)) {
 382		if (!peeking) {
 383			atomic_inc(&sk->sk_drops);
 384			SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 385		}
 386		kfree_skb(skb);
 387		return err;
 
 
 
 388	}
 389	if (!peeking)
 390		SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS);
 391
 392	sock_recv_ts_and_drops(msg, sk, skb);
 393
 394	/* Copy the address. */
 395	if (msg->msg_name) {
 396		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 
 
 397		sin6->sin6_family = AF_INET6;
 398		sin6->sin6_port = udp_hdr(skb)->source;
 399		sin6->sin6_flowinfo = 0;
 
 400
 401		if (is_udp4) {
 402			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 403					       &sin6->sin6_addr);
 404			sin6->sin6_scope_id = 0;
 405		} else {
 406			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 407			sin6->sin6_scope_id =
 408				ipv6_iface_scope_id(&sin6->sin6_addr,
 409						    inet6_iif(skb));
 410		}
 411		*addr_len = sizeof(*sin6);
 412
 413		if (cgroup_bpf_enabled)
 414			BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk,
 415						(struct sockaddr *)sin6);
 416	}
 417
 418	if (udp_sk(sk)->gro_enabled)
 419		udp_cmsg_recv(msg, sk, skb);
 420
 421	if (np->rxopt.all)
 422		ip6_datagram_recv_common_ctl(sk, msg, skb);
 423
 424	if (is_udp4) {
 425		if (inet->cmsg_flags)
 426			ip_cmsg_recv_offset(msg, sk, skb,
 427					    sizeof(struct udphdr), off);
 428	} else {
 429		if (np->rxopt.all)
 430			ip6_datagram_recv_specific_ctl(sk, msg, skb);
 431	}
 432
 433	err = copied;
 434	if (flags & MSG_TRUNC)
 435		err = ulen;
 436
 437	skb_consume_udp(sk, skb, peeking ? -err : err);
 
 
 438	return err;
 439
 440csum_copy_err:
 441	if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
 442				 udp_skb_destructor)) {
 443		SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS);
 444		SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 
 
 
 
 445	}
 446	kfree_skb(skb);
 447
 448	/* starting over for a new packet, but check if we need to yield */
 449	cond_resched();
 
 
 450	msg->msg_flags &= ~MSG_TRUNC;
 451	goto try_again;
 452}
 453
 454DEFINE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
 455void udpv6_encap_enable(void)
 456{
 457	static_branch_inc(&udpv6_encap_needed_key);
 458}
 459EXPORT_SYMBOL(udpv6_encap_enable);
 460
 461/* Handler for tunnels with arbitrary destination ports: no socket lookup, go
 462 * through error handlers in encapsulations looking for a match.
 463 */
 464static int __udp6_lib_err_encap_no_sk(struct sk_buff *skb,
 465				      struct inet6_skb_parm *opt,
 466				      u8 type, u8 code, int offset, __be32 info)
 467{
 468	int i;
 469
 470	for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) {
 471		int (*handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
 472			       u8 type, u8 code, int offset, __be32 info);
 473		const struct ip6_tnl_encap_ops *encap;
 474
 475		encap = rcu_dereference(ip6tun_encaps[i]);
 476		if (!encap)
 477			continue;
 478		handler = encap->err_handler;
 479		if (handler && !handler(skb, opt, type, code, offset, info))
 480			return 0;
 481	}
 482
 483	return -ENOENT;
 484}
 485
 486/* Try to match ICMP errors to UDP tunnels by looking up a socket without
 487 * reversing source and destination port: this will match tunnels that force the
 488 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that
 489 * lwtunnels might actually break this assumption by being configured with
 490 * different destination ports on endpoints, in this case we won't be able to
 491 * trace ICMP messages back to them.
 492 *
 493 * If this doesn't match any socket, probe tunnels with arbitrary destination
 494 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port
 495 * we've sent packets to won't necessarily match the local destination port.
 496 *
 497 * Then ask the tunnel implementation to match the error against a valid
 498 * association.
 499 *
 500 * Return an error if we can't find a match, the socket if we need further
 501 * processing, zero otherwise.
 502 */
 503static struct sock *__udp6_lib_err_encap(struct net *net,
 504					 const struct ipv6hdr *hdr, int offset,
 505					 struct udphdr *uh,
 506					 struct udp_table *udptable,
 507					 struct sk_buff *skb,
 508					 struct inet6_skb_parm *opt,
 509					 u8 type, u8 code, __be32 info)
 510{
 511	int network_offset, transport_offset;
 512	struct sock *sk;
 513
 514	network_offset = skb_network_offset(skb);
 515	transport_offset = skb_transport_offset(skb);
 516
 517	/* Network header needs to point to the outer IPv6 header inside ICMP */
 518	skb_reset_network_header(skb);
 519
 520	/* Transport header needs to point to the UDP header */
 521	skb_set_transport_header(skb, offset);
 522
 523	sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source,
 524			       &hdr->saddr, uh->dest,
 525			       inet6_iif(skb), 0, udptable, skb);
 526	if (sk) {
 527		int (*lookup)(struct sock *sk, struct sk_buff *skb);
 528		struct udp_sock *up = udp_sk(sk);
 529
 530		lookup = READ_ONCE(up->encap_err_lookup);
 531		if (!lookup || lookup(sk, skb))
 532			sk = NULL;
 533	}
 534
 535	if (!sk) {
 536		sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code,
 537							offset, info));
 538	}
 539
 540	skb_set_transport_header(skb, transport_offset);
 541	skb_set_network_header(skb, network_offset);
 542
 543	return sk;
 544}
 545
 546int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 547		   u8 type, u8 code, int offset, __be32 info,
 548		   struct udp_table *udptable)
 549{
 550	struct ipv6_pinfo *np;
 551	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 552	const struct in6_addr *saddr = &hdr->saddr;
 553	const struct in6_addr *daddr = &hdr->daddr;
 554	struct udphdr *uh = (struct udphdr *)(skb->data+offset);
 555	bool tunnel = false;
 556	struct sock *sk;
 557	int harderr;
 558	int err;
 559	struct net *net = dev_net(skb->dev);
 560
 561	sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
 562			       inet6_iif(skb), inet6_sdif(skb), udptable, NULL);
 563	if (!sk) {
 564		/* No socket for error: try tunnels before discarding */
 565		sk = ERR_PTR(-ENOENT);
 566		if (static_branch_unlikely(&udpv6_encap_needed_key)) {
 567			sk = __udp6_lib_err_encap(net, hdr, offset, uh,
 568						  udptable, skb,
 569						  opt, type, code, info);
 570			if (!sk)
 571				return 0;
 572		}
 573
 574		if (IS_ERR(sk)) {
 575			__ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
 576					  ICMP6_MIB_INERRORS);
 577			return PTR_ERR(sk);
 578		}
 579
 580		tunnel = true;
 581	}
 582
 583	harderr = icmpv6_err_convert(type, code, &err);
 584	np = inet6_sk(sk);
 585
 586	if (type == ICMPV6_PKT_TOOBIG) {
 587		if (!ip6_sk_accept_pmtu(sk))
 588			goto out;
 589		ip6_sk_update_pmtu(skb, sk, info);
 590		if (np->pmtudisc != IPV6_PMTUDISC_DONT)
 591			harderr = 1;
 592	}
 593	if (type == NDISC_REDIRECT) {
 594		if (tunnel) {
 595			ip6_redirect(skb, sock_net(sk), inet6_iif(skb),
 596				     sk->sk_mark, sk->sk_uid);
 597		} else {
 598			ip6_sk_redirect(skb, sk);
 599		}
 600		goto out;
 601	}
 602
 603	/* Tunnels don't have an application socket: don't pass errors back */
 604	if (tunnel)
 605		goto out;
 606
 607	if (!np->recverr) {
 608		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 609			goto out;
 610	} else {
 611		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 612	}
 613
 614	sk->sk_err = err;
 615	sk->sk_error_report(sk);
 616out:
 617	return 0;
 618}
 619
 620static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 621{
 622	int rc;
 623
 624	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 625		sock_rps_save_rxhash(sk, skb);
 626		sk_mark_napi_id(sk, skb);
 627		sk_incoming_cpu_update(sk);
 628	} else {
 629		sk_mark_napi_id_once(sk, skb);
 630	}
 631
 632	rc = __udp_enqueue_schedule_skb(sk, skb);
 633	if (rc < 0) {
 634		int is_udplite = IS_UDPLITE(sk);
 635
 636		/* Note that an ENOMEM error is charged twice */
 637		if (rc == -ENOMEM)
 638			UDP6_INC_STATS(sock_net(sk),
 639					 UDP_MIB_RCVBUFERRORS, is_udplite);
 640		UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 641		kfree_skb(skb);
 642		return -1;
 643	}
 644
 645	return 0;
 646}
 647
 648static __inline__ int udpv6_err(struct sk_buff *skb,
 649				struct inet6_skb_parm *opt, u8 type,
 650				u8 code, int offset, __be32 info)
 651{
 652	return __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 653}
 654
 655static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
 
 
 
 
 
 
 
 
 656{
 657	struct udp_sock *up = udp_sk(sk);
 
 658	int is_udplite = IS_UDPLITE(sk);
 659
 660	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 661		goto drop;
 662
 663	if (static_branch_unlikely(&udpv6_encap_needed_key) && up->encap_type) {
 664		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
 665
 666		/*
 667		 * This is an encapsulation socket so pass the skb to
 668		 * the socket's udp_encap_rcv() hook. Otherwise, just
 669		 * fall through and pass this up the UDP socket.
 670		 * up->encap_rcv() returns the following value:
 671		 * =0 if skb was successfully passed to the encap
 672		 *    handler or was discarded by it.
 673		 * >0 if skb should be passed on to UDP.
 674		 * <0 if skb should be resubmitted as proto -N
 675		 */
 676
 677		/* if we're overly short, let UDP handle it */
 678		encap_rcv = READ_ONCE(up->encap_rcv);
 679		if (encap_rcv) {
 680			int ret;
 681
 682			/* Verify checksum before giving to encap */
 683			if (udp_lib_checksum_complete(skb))
 684				goto csum_error;
 685
 686			ret = encap_rcv(sk, skb);
 687			if (ret <= 0) {
 688				__UDP_INC_STATS(sock_net(sk),
 689						UDP_MIB_INDATAGRAMS,
 690						is_udplite);
 691				return -ret;
 692			}
 693		}
 694
 695		/* FALLTHROUGH -- it's a UDP Packet */
 696	}
 697
 698	/*
 699	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 700	 */
 701	if ((up->pcflag & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 702
 703		if (up->pcrlen == 0) {          /* full coverage was set  */
 704			net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
 705					    UDP_SKB_CB(skb)->cscov, skb->len);
 
 706			goto drop;
 707		}
 708		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 709			net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
 710					    UDP_SKB_CB(skb)->cscov, up->pcrlen);
 
 711			goto drop;
 712		}
 713	}
 714
 715	prefetch(&sk->sk_rmem_alloc);
 716	if (rcu_access_pointer(sk->sk_filter) &&
 717	    udp_lib_checksum_complete(skb))
 718		goto csum_error;
 719
 720	if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
 721		goto drop;
 722
 723	udp_csum_pull_header(skb);
 724
 725	skb_dst_drop(skb);
 726
 727	return __udpv6_queue_rcv_skb(sk, skb);
 
 
 
 
 
 
 
 
 728
 729csum_error:
 730	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 731drop:
 732	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 733	atomic_inc(&sk->sk_drops);
 734	kfree_skb(skb);
 735	return -1;
 736}
 737
 738static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 739{
 740	struct sk_buff *next, *segs;
 741	int ret;
 
 
 
 
 742
 743	if (likely(!udp_unexpected_gso(sk, skb)))
 744		return udpv6_queue_rcv_one_skb(sk, skb);
 745
 746	__skb_push(skb, -skb_mac_offset(skb));
 747	segs = udp_rcv_segment(sk, skb, false);
 748	skb_list_walk_safe(segs, skb, next) {
 749		__skb_pull(skb, skb_transport_offset(skb));
 750
 751		ret = udpv6_queue_rcv_one_skb(sk, skb);
 752		if (ret > 0)
 753			ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret,
 754						 true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 755	}
 756	return 0;
 757}
 758
 759static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
 760				   __be16 loc_port, const struct in6_addr *loc_addr,
 761				   __be16 rmt_port, const struct in6_addr *rmt_addr,
 762				   int dif, int sdif, unsigned short hnum)
 763{
 764	struct inet_sock *inet = inet_sk(sk);
 765
 766	if (!net_eq(sock_net(sk), net))
 767		return false;
 768
 769	if (udp_sk(sk)->udp_port_hash != hnum ||
 770	    sk->sk_family != PF_INET6 ||
 771	    (inet->inet_dport && inet->inet_dport != rmt_port) ||
 772	    (!ipv6_addr_any(&sk->sk_v6_daddr) &&
 773		    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
 774	    !udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif) ||
 775	    (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 776		    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
 777		return false;
 778	if (!inet6_mc_check(sk, loc_addr, rmt_addr))
 779		return false;
 780	return true;
 781}
 782
 783static void udp6_csum_zero_error(struct sk_buff *skb)
 784{
 785	/* RFC 2460 section 8.1 says that we SHOULD log
 786	 * this error. Well, it is reasonable.
 787	 */
 788	net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
 789			    &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
 790			    &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
 791}
 792
 793/*
 794 * Note: called only from the BH handler context,
 795 * so we don't need to lock the hashes.
 796 */
 797static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 798		const struct in6_addr *saddr, const struct in6_addr *daddr,
 799		struct udp_table *udptable, int proto)
 800{
 801	struct sock *sk, *first = NULL;
 802	const struct udphdr *uh = udp_hdr(skb);
 803	unsigned short hnum = ntohs(uh->dest);
 804	struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
 805	unsigned int offset = offsetof(typeof(*sk), sk_node);
 806	unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
 807	int dif = inet6_iif(skb);
 808	int sdif = inet6_sdif(skb);
 809	struct hlist_node *node;
 810	struct sk_buff *nskb;
 811
 812	if (use_hash2) {
 813		hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
 814			    udptable->mask;
 815		hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
 816start_lookup:
 817		hslot = &udptable->hash2[hash2];
 818		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 819	}
 820
 821	sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
 822		if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
 823					    uh->source, saddr, dif, sdif,
 824					    hnum))
 825			continue;
 826		/* If zero checksum and no_check is not on for
 827		 * the socket then skip it.
 828		 */
 829		if (!uh->check && !udp_sk(sk)->no_check6_rx)
 830			continue;
 831		if (!first) {
 832			first = sk;
 833			continue;
 834		}
 835		nskb = skb_clone(skb, GFP_ATOMIC);
 836		if (unlikely(!nskb)) {
 837			atomic_inc(&sk->sk_drops);
 838			__UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
 839					 IS_UDPLITE(sk));
 840			__UDP6_INC_STATS(net, UDP_MIB_INERRORS,
 841					 IS_UDPLITE(sk));
 842			continue;
 843		}
 844
 845		if (udpv6_queue_rcv_skb(sk, nskb) > 0)
 846			consume_skb(nskb);
 847	}
 
 
 
 
 
 848
 849	/* Also lookup *:port if we are using hash2 and haven't done so yet. */
 850	if (use_hash2 && hash2 != hash2_any) {
 851		hash2 = hash2_any;
 852		goto start_lookup;
 853	}
 854
 855	if (first) {
 856		if (udpv6_queue_rcv_skb(first, skb) > 0)
 857			consume_skb(skb);
 858	} else {
 859		kfree_skb(skb);
 860		__UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
 861				 proto == IPPROTO_UDPLITE);
 862	}
 863	return 0;
 864}
 865
 866static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
 
 867{
 868	if (udp_sk_rx_dst_set(sk, dst)) {
 869		const struct rt6_info *rt = (const struct rt6_info *)dst;
 870
 871		inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt);
 872	}
 873}
 874
 875/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
 876 * return code conversion for ip layer consumption
 877 */
 878static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
 879				struct udphdr *uh)
 880{
 881	int ret;
 882
 883	if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
 884		skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo);
 885
 886	ret = udpv6_queue_rcv_skb(sk, skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 887
 888	/* a return value > 0 means to resubmit the input */
 889	if (ret > 0)
 890		return ret;
 891	return 0;
 892}
 893
 894int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 895		   int proto)
 896{
 897	const struct in6_addr *saddr, *daddr;
 898	struct net *net = dev_net(skb->dev);
 899	struct udphdr *uh;
 900	struct sock *sk;
 901	bool refcounted;
 
 902	u32 ulen = 0;
 903
 904	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 905		goto discard;
 906
 907	saddr = &ipv6_hdr(skb)->saddr;
 908	daddr = &ipv6_hdr(skb)->daddr;
 909	uh = udp_hdr(skb);
 910
 911	ulen = ntohs(uh->len);
 912	if (ulen > skb->len)
 913		goto short_packet;
 914
 915	if (proto == IPPROTO_UDP) {
 916		/* UDP validates ulen. */
 917
 918		/* Check for jumbo payload */
 919		if (ulen == 0)
 920			ulen = skb->len;
 921
 922		if (ulen < sizeof(*uh))
 923			goto short_packet;
 924
 925		if (ulen < skb->len) {
 926			if (pskb_trim_rcsum(skb, ulen))
 927				goto short_packet;
 928			saddr = &ipv6_hdr(skb)->saddr;
 929			daddr = &ipv6_hdr(skb)->daddr;
 930			uh = udp_hdr(skb);
 931		}
 932	}
 933
 934	if (udp6_csum_init(skb, uh, proto))
 935		goto csum_error;
 936
 937	/* Check if the socket is already available, e.g. due to early demux */
 938	sk = skb_steal_sock(skb, &refcounted);
 939	if (sk) {
 940		struct dst_entry *dst = skb_dst(skb);
 941		int ret;
 942
 943		if (unlikely(sk->sk_rx_dst != dst))
 944			udp6_sk_rx_dst_set(sk, dst);
 945
 946		if (!uh->check && !udp_sk(sk)->no_check6_rx) {
 947			if (refcounted)
 948				sock_put(sk);
 949			goto report_csum_error;
 950		}
 951
 952		ret = udp6_unicast_rcv_skb(sk, skb, uh);
 953		if (refcounted)
 954			sock_put(sk);
 955		return ret;
 956	}
 957
 958	/*
 959	 *	Multicast receive code
 960	 */
 961	if (ipv6_addr_is_multicast(daddr))
 962		return __udp6_lib_mcast_deliver(net, skb,
 963				saddr, daddr, udptable, proto);
 964
 965	/* Unicast */
 
 
 
 
 
 966	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
 967	if (sk) {
 968		if (!uh->check && !udp_sk(sk)->no_check6_rx)
 969			goto report_csum_error;
 970		return udp6_unicast_rcv_skb(sk, skb, uh);
 971	}
 
 
 
 
 972
 973	if (!uh->check)
 974		goto report_csum_error;
 975
 976	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 977		goto discard;
 978
 979	if (udp_lib_checksum_complete(skb))
 980		goto csum_error;
 981
 982	__UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
 983	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 984
 985	kfree_skb(skb);
 986	return 0;
 987
 988short_packet:
 989	net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
 990			    proto == IPPROTO_UDPLITE ? "-Lite" : "",
 991			    saddr, ntohs(uh->source),
 992			    ulen, skb->len,
 993			    daddr, ntohs(uh->dest));
 994	goto discard;
 995
 996report_csum_error:
 997	udp6_csum_zero_error(skb);
 998csum_error:
 999	__UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
1000discard:
1001	__UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
1002	kfree_skb(skb);
1003	return 0;
1004}
1005
1006
1007static struct sock *__udp6_lib_demux_lookup(struct net *net,
1008			__be16 loc_port, const struct in6_addr *loc_addr,
1009			__be16 rmt_port, const struct in6_addr *rmt_addr,
1010			int dif, int sdif)
1011{
1012	unsigned short hnum = ntohs(loc_port);
1013	unsigned int hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
1014	unsigned int slot2 = hash2 & udp_table.mask;
1015	struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
1016	const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
1017	struct sock *sk;
1018
1019	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
1020		if (sk->sk_state == TCP_ESTABLISHED &&
1021		    INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif, sdif))
1022			return sk;
1023		/* Only check first socket in chain */
1024		break;
1025	}
1026	return NULL;
1027}
1028
1029INDIRECT_CALLABLE_SCOPE void udp_v6_early_demux(struct sk_buff *skb)
1030{
1031	struct net *net = dev_net(skb->dev);
1032	const struct udphdr *uh;
1033	struct sock *sk;
1034	struct dst_entry *dst;
1035	int dif = skb->dev->ifindex;
1036	int sdif = inet6_sdif(skb);
1037
1038	if (!pskb_may_pull(skb, skb_transport_offset(skb) +
1039	    sizeof(struct udphdr)))
1040		return;
1041
1042	uh = udp_hdr(skb);
1043
1044	if (skb->pkt_type == PACKET_HOST)
1045		sk = __udp6_lib_demux_lookup(net, uh->dest,
1046					     &ipv6_hdr(skb)->daddr,
1047					     uh->source, &ipv6_hdr(skb)->saddr,
1048					     dif, sdif);
1049	else
1050		return;
1051
1052	if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
1053		return;
1054
1055	skb->sk = sk;
1056	skb->destructor = sock_efree;
1057	dst = READ_ONCE(sk->sk_rx_dst);
1058
1059	if (dst)
1060		dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);
1061	if (dst) {
1062		/* set noref for now.
1063		 * any place which wants to hold dst has to call
1064		 * dst_hold_safe()
1065		 */
1066		skb_dst_set_noref(skb, dst);
1067	}
1068}
1069
1070INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb)
1071{
1072	return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
1073}
1074
1075/*
1076 * Throw away all pending data and cancel the corking. Socket is locked.
1077 */
1078static void udp_v6_flush_pending_frames(struct sock *sk)
1079{
1080	struct udp_sock *up = udp_sk(sk);
1081
1082	if (up->pending == AF_INET)
1083		udp_flush_pending_frames(sk);
1084	else if (up->pending) {
1085		up->len = 0;
1086		up->pending = 0;
1087		ip6_flush_pending_frames(sk);
1088	}
1089}
1090
1091static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
1092			     int addr_len)
1093{
1094	if (addr_len < offsetofend(struct sockaddr, sa_family))
1095		return -EINVAL;
1096	/* The following checks are replicated from __ip6_datagram_connect()
1097	 * and intended to prevent BPF program called below from accessing
1098	 * bytes that are out of the bound specified by user in addr_len.
1099	 */
1100	if (uaddr->sa_family == AF_INET) {
1101		if (__ipv6_only_sock(sk))
1102			return -EAFNOSUPPORT;
1103		return udp_pre_connect(sk, uaddr, addr_len);
1104	}
1105
1106	if (addr_len < SIN6_LEN_RFC2133)
1107		return -EINVAL;
1108
1109	return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr);
1110}
1111
1112/**
1113 *	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
1114 *	@sk:	socket we are sending on
1115 *	@skb:	sk_buff containing the filled-in UDP header
1116 *		(checksum field must be zeroed out)
1117 *	@saddr: source address
1118 *	@daddr: destination address
1119 *	@len:	length of packet
1120 */
1121static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
1122				 const struct in6_addr *saddr,
1123				 const struct in6_addr *daddr, int len)
1124{
1125	unsigned int offset;
1126	struct udphdr *uh = udp_hdr(skb);
1127	struct sk_buff *frags = skb_shinfo(skb)->frag_list;
1128	__wsum csum = 0;
1129
1130	if (!frags) {
1131		/* Only one fragment on the socket.  */
1132		skb->csum_start = skb_transport_header(skb) - skb->head;
1133		skb->csum_offset = offsetof(struct udphdr, check);
1134		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1135	} else {
1136		/*
1137		 * HW-checksum won't work as there are two or more
1138		 * fragments on the socket so that all csums of sk_buffs
1139		 * should be together
1140		 */
1141		offset = skb_transport_offset(skb);
1142		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1143		csum = skb->csum;
1144
1145		skb->ip_summed = CHECKSUM_NONE;
1146
1147		do {
1148			csum = csum_add(csum, frags->csum);
1149		} while ((frags = frags->next));
1150
1151		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1152					    csum);
1153		if (uh->check == 0)
1154			uh->check = CSUM_MANGLED_0;
1155	}
1156}
1157
1158/*
1159 *	Sending
1160 */
1161
1162static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
1163			   struct inet_cork *cork)
1164{
1165	struct sock *sk = skb->sk;
1166	struct udphdr *uh;
 
 
 
1167	int err = 0;
1168	int is_udplite = IS_UDPLITE(sk);
1169	__wsum csum = 0;
1170	int offset = skb_transport_offset(skb);
1171	int len = skb->len - offset;
1172	int datalen = len - sizeof(*uh);
 
1173
1174	/*
1175	 * Create a UDP header
1176	 */
1177	uh = udp_hdr(skb);
1178	uh->source = fl6->fl6_sport;
1179	uh->dest = fl6->fl6_dport;
1180	uh->len = htons(len);
1181	uh->check = 0;
1182
1183	if (cork->gso_size) {
1184		const int hlen = skb_network_header_len(skb) +
1185				 sizeof(struct udphdr);
1186
1187		if (hlen + cork->gso_size > cork->fragsize) {
1188			kfree_skb(skb);
1189			return -EINVAL;
1190		}
1191		if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) {
1192			kfree_skb(skb);
1193			return -EINVAL;
1194		}
1195		if (udp_sk(sk)->no_check6_tx) {
1196			kfree_skb(skb);
1197			return -EINVAL;
1198		}
1199		if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
1200		    dst_xfrm(skb_dst(skb))) {
1201			kfree_skb(skb);
1202			return -EIO;
1203		}
1204
1205		if (datalen > cork->gso_size) {
1206			skb_shinfo(skb)->gso_size = cork->gso_size;
1207			skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
1208			skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
1209								 cork->gso_size);
1210		}
1211		goto csum_partial;
1212	}
1213
1214	if (is_udplite)
1215		csum = udplite_csum(skb);
1216	else if (udp_sk(sk)->no_check6_tx) {   /* UDP csum disabled */
1217		skb->ip_summed = CHECKSUM_NONE;
1218		goto send;
1219	} else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1220csum_partial:
1221		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1222		goto send;
1223	} else
1224		csum = udp_csum(skb);
1225
1226	/* add protocol-dependent pseudo-header */
1227	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1228				    len, fl6->flowi6_proto, csum);
1229	if (uh->check == 0)
1230		uh->check = CSUM_MANGLED_0;
1231
1232send:
1233	err = ip6_send_skb(skb);
1234	if (err) {
1235		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1236			UDP6_INC_STATS(sock_net(sk),
1237				       UDP_MIB_SNDBUFERRORS, is_udplite);
1238			err = 0;
1239		}
1240	} else {
1241		UDP6_INC_STATS(sock_net(sk),
1242			       UDP_MIB_OUTDATAGRAMS, is_udplite);
1243	}
1244	return err;
1245}
1246
1247static int udp_v6_push_pending_frames(struct sock *sk)
1248{
1249	struct sk_buff *skb;
1250	struct udp_sock  *up = udp_sk(sk);
1251	struct flowi6 fl6;
1252	int err = 0;
1253
1254	if (up->pending == AF_INET)
1255		return udp_push_pending_frames(sk);
1256
1257	/* ip6_finish_skb will release the cork, so make a copy of
1258	 * fl6 here.
1259	 */
1260	fl6 = inet_sk(sk)->cork.fl.u.ip6;
1261
1262	skb = ip6_finish_skb(sk);
1263	if (!skb)
1264		goto out;
1265
1266	err = udp_v6_send_skb(skb, &fl6, &inet_sk(sk)->cork.base);
1267
1268out:
1269	up->len = 0;
1270	up->pending = 0;
1271	return err;
1272}
1273
1274int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
1275{
1276	struct ipv6_txoptions opt_space;
1277	struct udp_sock *up = udp_sk(sk);
1278	struct inet_sock *inet = inet_sk(sk);
1279	struct ipv6_pinfo *np = inet6_sk(sk);
1280	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1281	struct in6_addr *daddr, *final_p, final;
1282	struct ipv6_txoptions *opt = NULL;
1283	struct ipv6_txoptions *opt_to_free = NULL;
1284	struct ip6_flowlabel *flowlabel = NULL;
1285	struct flowi6 fl6;
1286	struct dst_entry *dst;
1287	struct ipcm6_cookie ipc6;
1288	int addr_len = msg->msg_namelen;
1289	bool connected = false;
1290	int ulen = len;
 
 
 
1291	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1292	int err;
 
1293	int is_udplite = IS_UDPLITE(sk);
1294	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1295
1296	ipcm6_init(&ipc6);
1297	ipc6.gso_size = up->gso_size;
1298	ipc6.sockc.tsflags = sk->sk_tsflags;
1299	ipc6.sockc.mark = sk->sk_mark;
1300
1301	/* destination address check */
1302	if (sin6) {
1303		if (addr_len < offsetof(struct sockaddr, sa_data))
1304			return -EINVAL;
1305
1306		switch (sin6->sin6_family) {
1307		case AF_INET6:
1308			if (addr_len < SIN6_LEN_RFC2133)
1309				return -EINVAL;
1310			daddr = &sin6->sin6_addr;
1311			if (ipv6_addr_any(daddr) &&
1312			    ipv6_addr_v4mapped(&np->saddr))
1313				ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1314						       daddr);
1315			break;
1316		case AF_INET:
1317			goto do_udp_sendmsg;
1318		case AF_UNSPEC:
1319			msg->msg_name = sin6 = NULL;
1320			msg->msg_namelen = addr_len = 0;
1321			daddr = NULL;
1322			break;
1323		default:
1324			return -EINVAL;
1325		}
1326	} else if (!up->pending) {
1327		if (sk->sk_state != TCP_ESTABLISHED)
1328			return -EDESTADDRREQ;
1329		daddr = &sk->sk_v6_daddr;
1330	} else
1331		daddr = NULL;
1332
1333	if (daddr) {
1334		if (ipv6_addr_v4mapped(daddr)) {
1335			struct sockaddr_in sin;
1336			sin.sin_family = AF_INET;
1337			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1338			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1339			msg->msg_name = &sin;
1340			msg->msg_namelen = sizeof(sin);
1341do_udp_sendmsg:
1342			if (__ipv6_only_sock(sk))
1343				return -ENETUNREACH;
1344			return udp_sendmsg(sk, msg, len);
1345		}
1346	}
1347
1348	if (up->pending == AF_INET)
1349		return udp_sendmsg(sk, msg, len);
1350
1351	/* Rough check on arithmetic overflow,
1352	   better check is made in ip6_append_data().
1353	   */
1354	if (len > INT_MAX - sizeof(struct udphdr))
1355		return -EMSGSIZE;
1356
1357	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1358	if (up->pending) {
1359		/*
1360		 * There are pending frames.
1361		 * The socket lock must be held while it's corked.
1362		 */
1363		lock_sock(sk);
1364		if (likely(up->pending)) {
1365			if (unlikely(up->pending != AF_INET6)) {
1366				release_sock(sk);
1367				return -EAFNOSUPPORT;
1368			}
1369			dst = NULL;
1370			goto do_append_data;
1371		}
1372		release_sock(sk);
1373	}
1374	ulen += sizeof(struct udphdr);
1375
1376	memset(&fl6, 0, sizeof(fl6));
1377
1378	if (sin6) {
1379		if (sin6->sin6_port == 0)
1380			return -EINVAL;
1381
1382		fl6.fl6_dport = sin6->sin6_port;
1383		daddr = &sin6->sin6_addr;
1384
1385		if (np->sndflow) {
1386			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1387			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1388				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1389				if (IS_ERR(flowlabel))
1390					return -EINVAL;
 
1391			}
1392		}
1393
1394		/*
1395		 * Otherwise it will be difficult to maintain
1396		 * sk->sk_dst_cache.
1397		 */
1398		if (sk->sk_state == TCP_ESTABLISHED &&
1399		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1400			daddr = &sk->sk_v6_daddr;
1401
1402		if (addr_len >= sizeof(struct sockaddr_in6) &&
1403		    sin6->sin6_scope_id &&
1404		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1405			fl6.flowi6_oif = sin6->sin6_scope_id;
1406	} else {
1407		if (sk->sk_state != TCP_ESTABLISHED)
1408			return -EDESTADDRREQ;
1409
1410		fl6.fl6_dport = inet->inet_dport;
1411		daddr = &sk->sk_v6_daddr;
1412		fl6.flowlabel = np->flow_label;
1413		connected = true;
1414	}
1415
1416	if (!fl6.flowi6_oif)
1417		fl6.flowi6_oif = sk->sk_bound_dev_if;
1418
1419	if (!fl6.flowi6_oif)
1420		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1421
1422	fl6.flowi6_mark = ipc6.sockc.mark;
1423	fl6.flowi6_uid = sk->sk_uid;
1424
1425	if (msg->msg_controllen) {
1426		opt = &opt_space;
1427		memset(opt, 0, sizeof(struct ipv6_txoptions));
1428		opt->tot_len = sizeof(*opt);
1429		ipc6.opt = opt;
1430
1431		err = udp_cmsg_send(sk, msg, &ipc6.gso_size);
1432		if (err > 0)
1433			err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6,
1434						    &ipc6);
1435		if (err < 0) {
1436			fl6_sock_release(flowlabel);
1437			return err;
1438		}
1439		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1440			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1441			if (IS_ERR(flowlabel))
1442				return -EINVAL;
1443		}
1444		if (!(opt->opt_nflen|opt->opt_flen))
1445			opt = NULL;
1446		connected = false;
1447	}
1448	if (!opt) {
1449		opt = txopt_get(np);
1450		opt_to_free = opt;
1451	}
 
 
1452	if (flowlabel)
1453		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1454	opt = ipv6_fixup_options(&opt_space, opt);
1455	ipc6.opt = opt;
1456
1457	fl6.flowi6_proto = sk->sk_protocol;
1458	fl6.daddr = *daddr;
 
 
 
1459	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1460		fl6.saddr = np->saddr;
1461	fl6.fl6_sport = inet->inet_sport;
1462
1463	if (cgroup_bpf_enabled && !connected) {
1464		err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk,
1465					   (struct sockaddr *)sin6, &fl6.saddr);
1466		if (err)
1467			goto out_no_dst;
1468		if (sin6) {
1469			if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
1470				/* BPF program rewrote IPv6-only by IPv4-mapped
1471				 * IPv6. It's currently unsupported.
1472				 */
1473				err = -ENOTSUPP;
1474				goto out_no_dst;
1475			}
1476			if (sin6->sin6_port == 0) {
1477				/* BPF program set invalid port. Reject it. */
1478				err = -EINVAL;
1479				goto out_no_dst;
1480			}
1481			fl6.fl6_dport = sin6->sin6_port;
1482			fl6.daddr = sin6->sin6_addr;
1483		}
1484	}
1485
1486	if (ipv6_addr_any(&fl6.daddr))
1487		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1488
1489	final_p = fl6_update_dst(&fl6, opt, &final);
1490	if (final_p)
1491		connected = false;
1492
1493	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1494		fl6.flowi6_oif = np->mcast_oif;
1495		connected = false;
1496	} else if (!fl6.flowi6_oif)
1497		fl6.flowi6_oif = np->ucast_oif;
1498
1499	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1500
1501	if (ipc6.tclass < 0)
1502		ipc6.tclass = np->tclass;
1503
1504	fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
1505
1506	dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, connected);
1507	if (IS_ERR(dst)) {
1508		err = PTR_ERR(dst);
1509		dst = NULL;
1510		goto out;
1511	}
1512
1513	if (ipc6.hlimit < 0)
1514		ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 
 
 
 
 
 
 
 
 
 
 
 
1515
1516	if (msg->msg_flags&MSG_CONFIRM)
1517		goto do_confirm;
1518back_from_confirm:
1519
1520	/* Lockless fast path for the non-corking case */
1521	if (!corkreq) {
1522		struct inet_cork_full cork;
1523		struct sk_buff *skb;
1524
1525		skb = ip6_make_skb(sk, getfrag, msg, ulen,
1526				   sizeof(struct udphdr), &ipc6,
1527				   &fl6, (struct rt6_info *)dst,
1528				   msg->msg_flags, &cork);
1529		err = PTR_ERR(skb);
1530		if (!IS_ERR_OR_NULL(skb))
1531			err = udp_v6_send_skb(skb, &fl6, &cork.base);
1532		goto out;
1533	}
1534
1535	lock_sock(sk);
1536	if (unlikely(up->pending)) {
1537		/* The socket is already corked while preparing it. */
1538		/* ... which is an evident application bug. --ANK */
1539		release_sock(sk);
1540
1541		net_dbg_ratelimited("udp cork app bug 2\n");
1542		err = -EINVAL;
1543		goto out;
1544	}
1545
1546	up->pending = AF_INET6;
1547
1548do_append_data:
1549	if (ipc6.dontfrag < 0)
1550		ipc6.dontfrag = np->dontfrag;
1551	up->len += ulen;
1552	err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1553			      &ipc6, &fl6, (struct rt6_info *)dst,
1554			      corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
 
 
1555	if (err)
1556		udp_v6_flush_pending_frames(sk);
1557	else if (!corkreq)
1558		err = udp_v6_push_pending_frames(sk);
1559	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1560		up->pending = 0;
1561
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1562	if (err > 0)
1563		err = np->recverr ? net_xmit_errno(err) : 0;
1564	release_sock(sk);
1565
1566out:
1567	dst_release(dst);
1568out_no_dst:
1569	fl6_sock_release(flowlabel);
1570	txopt_put(opt_to_free);
1571	if (!err)
1572		return len;
1573	/*
1574	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1575	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1576	 * we don't have a good statistic (IpOutDiscards but it can be too many
1577	 * things).  We could add another new stat but at least for now that
1578	 * seems like overkill.
1579	 */
1580	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1581		UDP6_INC_STATS(sock_net(sk),
1582			       UDP_MIB_SNDBUFERRORS, is_udplite);
1583	}
1584	return err;
1585
1586do_confirm:
1587	if (msg->msg_flags & MSG_PROBE)
1588		dst_confirm_neigh(dst, &fl6.daddr);
1589	if (!(msg->msg_flags&MSG_PROBE) || len)
1590		goto back_from_confirm;
1591	err = 0;
1592	goto out;
1593}
1594
1595void udpv6_destroy_sock(struct sock *sk)
1596{
1597	struct udp_sock *up = udp_sk(sk);
1598	lock_sock(sk);
1599	udp_v6_flush_pending_frames(sk);
1600	release_sock(sk);
1601
1602	if (static_branch_unlikely(&udpv6_encap_needed_key)) {
1603		if (up->encap_type) {
1604			void (*encap_destroy)(struct sock *sk);
1605			encap_destroy = READ_ONCE(up->encap_destroy);
1606			if (encap_destroy)
1607				encap_destroy(sk);
1608		}
1609		if (up->encap_enabled)
1610			static_branch_dec(&udpv6_encap_needed_key);
1611	}
1612
1613	inet6_destroy_sock(sk);
1614}
1615
1616/*
1617 *	Socket option code for UDP
1618 */
1619int udpv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1620		     unsigned int optlen)
1621{
1622	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1623		return udp_lib_setsockopt(sk, level, optname,
1624					  optval, optlen,
1625					  udp_v6_push_pending_frames);
1626	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1627}
1628
 
 
 
 
 
 
 
 
 
 
 
1629int udpv6_getsockopt(struct sock *sk, int level, int optname,
1630		     char __user *optval, int __user *optlen)
1631{
1632	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1633		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1634	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1635}
1636
1637/* thinking of making this const? Don't.
1638 * early_demux can change based on sysctl.
1639 */
1640static struct inet6_protocol udpv6_protocol = {
1641	.early_demux	=	udp_v6_early_demux,
1642	.early_demux_handler =  udp_v6_early_demux,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1643	.handler	=	udpv6_rcv,
1644	.err_handler	=	udpv6_err,
 
 
1645	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1646};
1647
1648/* ------------------------------------------------------------------------ */
1649#ifdef CONFIG_PROC_FS
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1650int udp6_seq_show(struct seq_file *seq, void *v)
1651{
1652	if (v == SEQ_START_TOKEN) {
1653		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1654	} else {
1655		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1656		struct inet_sock *inet = inet_sk(v);
1657		__u16 srcp = ntohs(inet->inet_sport);
1658		__u16 destp = ntohs(inet->inet_dport);
1659		__ip6_dgram_sock_seq_show(seq, v, srcp, destp,
1660					  udp_rqueue_get(v), bucket);
1661	}
1662	return 0;
1663}
1664
1665const struct seq_operations udp6_seq_ops = {
1666	.start		= udp_seq_start,
1667	.next		= udp_seq_next,
1668	.stop		= udp_seq_stop,
1669	.show		= udp6_seq_show,
 
1670};
1671EXPORT_SYMBOL(udp6_seq_ops);
1672
1673static struct udp_seq_afinfo udp6_seq_afinfo = {
 
1674	.family		= AF_INET6,
1675	.udp_table	= &udp_table,
 
 
 
 
1676};
1677
1678int __net_init udp6_proc_init(struct net *net)
1679{
1680	if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops,
1681			sizeof(struct udp_iter_state), &udp6_seq_afinfo))
1682		return -ENOMEM;
1683	return 0;
1684}
1685
1686void udp6_proc_exit(struct net *net)
1687{
1688	remove_proc_entry("udp6", net->proc_net);
1689}
1690#endif /* CONFIG_PROC_FS */
1691
1692/* ------------------------------------------------------------------------ */
1693
1694struct proto udpv6_prot = {
1695	.name			= "UDPv6",
1696	.owner			= THIS_MODULE,
1697	.close			= udp_lib_close,
1698	.pre_connect		= udpv6_pre_connect,
1699	.connect		= ip6_datagram_connect,
1700	.disconnect		= udp_disconnect,
1701	.ioctl			= udp_ioctl,
1702	.init			= udp_init_sock,
1703	.destroy		= udpv6_destroy_sock,
1704	.setsockopt		= udpv6_setsockopt,
1705	.getsockopt		= udpv6_getsockopt,
1706	.sendmsg		= udpv6_sendmsg,
1707	.recvmsg		= udpv6_recvmsg,
1708	.release_cb		= ip6_datagram_release_cb,
1709	.hash			= udp_lib_hash,
1710	.unhash			= udp_lib_unhash,
1711	.rehash			= udp_v6_rehash,
1712	.get_port		= udp_v6_get_port,
1713	.memory_allocated	= &udp_memory_allocated,
1714	.sysctl_mem		= sysctl_udp_mem,
1715	.sysctl_wmem_offset     = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1716	.sysctl_rmem_offset     = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1717	.obj_size		= sizeof(struct udp6_sock),
1718	.h.udp_table		= &udp_table,
1719	.diag_destroy		= udp_abort,
 
 
 
1720};
1721
1722static struct inet_protosw udpv6_protosw = {
1723	.type =      SOCK_DGRAM,
1724	.protocol =  IPPROTO_UDP,
1725	.prot =      &udpv6_prot,
1726	.ops =       &inet6_dgram_ops,
 
1727	.flags =     INET_PROTOSW_PERMANENT,
1728};
 
1729
1730int __init udpv6_init(void)
1731{
1732	int ret;
1733
1734	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1735	if (ret)
1736		goto out;
1737
1738	ret = inet6_register_protosw(&udpv6_protosw);
1739	if (ret)
1740		goto out_udpv6_protocol;
1741out:
1742	return ret;
1743
1744out_udpv6_protocol:
1745	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1746	goto out;
1747}
1748
1749void udpv6_exit(void)
1750{
1751	inet6_unregister_protosw(&udpv6_protosw);
1752	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1753}
v3.5.6
 
   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
 
 241struct 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}
 308EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
 309
 310static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 311					  __be16 sport, __be16 dport,
 312					  struct udp_table *udptable)
 313{
 314	struct sock *sk;
 315	const struct ipv6hdr *iph = ipv6_hdr(skb);
 316
 317	if (unlikely(sk = skb_steal_sock(skb)))
 318		return sk;
 319	return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
 
 
 
 
 
 
 
 
 320				 &iph->daddr, dport, inet6_iif(skb),
 321				 udptable);
 322}
 
 323
 
 
 
 
 324struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 325			     const struct in6_addr *daddr, __be16 dport, int dif)
 326{
 327	return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
 
 
 
 
 
 
 328}
 329EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 
 330
 
 
 
 
 
 
 
 
 331
 332/*
 333 * 	This should be easy, if there is something there we
 334 * 	return it, otherwise we block.
 335 */
 336
 337int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 338		  struct msghdr *msg, size_t len,
 339		  int noblock, int flags, int *addr_len)
 340{
 341	struct ipv6_pinfo *np = inet6_sk(sk);
 342	struct inet_sock *inet = inet_sk(sk);
 343	struct sk_buff *skb;
 344	unsigned int ulen, copied;
 345	int peeked, off = 0;
 346	int err;
 347	int is_udplite = IS_UDPLITE(sk);
 
 
 348	int is_udp4;
 349	bool slow;
 350
 351	if (addr_len)
 352		*addr_len = sizeof(struct sockaddr_in6);
 353
 354	if (flags & MSG_ERRQUEUE)
 355		return ipv6_recv_error(sk, msg, len);
 356
 357	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 358		return ipv6_recv_rxpmtu(sk, msg, len);
 359
 360try_again:
 361	skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
 362				  &peeked, &off, &err);
 363	if (!skb)
 364		goto out;
 365
 366	ulen = skb->len - sizeof(struct udphdr);
 367	copied = len;
 368	if (copied > ulen)
 369		copied = ulen;
 370	else if (copied < ulen)
 371		msg->msg_flags |= MSG_TRUNC;
 372
 373	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 
 374
 375	/*
 376	 * If checksum is needed at all, try to do it while copying the
 377	 * data.  If the data is truncated, or if we only want a partial
 378	 * coverage checksum (UDP-Lite), do it before the copy.
 379	 */
 380
 381	if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
 382		if (udp_lib_checksum_complete(skb))
 
 
 
 383			goto csum_copy_err;
 384	}
 385
 386	if (skb_csum_unnecessary(skb))
 387		err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
 388					      msg->msg_iov, copied       );
 389	else {
 390		err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 
 
 391		if (err == -EINVAL)
 392			goto csum_copy_err;
 393	}
 394	if (err)
 395		goto out_free;
 396
 397	if (!peeked) {
 398		if (is_udp4)
 399			UDP_INC_STATS_USER(sock_net(sk),
 400					UDP_MIB_INDATAGRAMS, is_udplite);
 401		else
 402			UDP6_INC_STATS_USER(sock_net(sk),
 403					UDP_MIB_INDATAGRAMS, is_udplite);
 404	}
 
 
 405
 406	sock_recv_ts_and_drops(msg, sk, skb);
 407
 408	/* Copy the address. */
 409	if (msg->msg_name) {
 410		struct sockaddr_in6 *sin6;
 411
 412		sin6 = (struct sockaddr_in6 *) msg->msg_name;
 413		sin6->sin6_family = AF_INET6;
 414		sin6->sin6_port = udp_hdr(skb)->source;
 415		sin6->sin6_flowinfo = 0;
 416		sin6->sin6_scope_id = 0;
 417
 418		if (is_udp4)
 419			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 420					       &sin6->sin6_addr);
 421		else {
 
 422			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 423			if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 424				sin6->sin6_scope_id = IP6CB(skb)->iif;
 
 425		}
 
 426
 
 
 
 427	}
 
 
 
 
 
 
 
 428	if (is_udp4) {
 429		if (inet->cmsg_flags)
 430			ip_cmsg_recv(msg, skb);
 
 431	} else {
 432		if (np->rxopt.all)
 433			datagram_recv_ctl(sk, msg, skb);
 434	}
 435
 436	err = copied;
 437	if (flags & MSG_TRUNC)
 438		err = ulen;
 439
 440out_free:
 441	skb_free_datagram_locked(sk, skb);
 442out:
 443	return err;
 444
 445csum_copy_err:
 446	slow = lock_sock_fast(sk);
 447	if (!skb_kill_datagram(sk, skb, flags)) {
 448		if (is_udp4)
 449			UDP_INC_STATS_USER(sock_net(sk),
 450					UDP_MIB_INERRORS, is_udplite);
 451		else
 452			UDP6_INC_STATS_USER(sock_net(sk),
 453					UDP_MIB_INERRORS, is_udplite);
 454	}
 455	unlock_sock_fast(sk, slow);
 456
 457	if (noblock)
 458		return -EAGAIN;
 459
 460	/* starting over for a new packet */
 461	msg->msg_flags &= ~MSG_TRUNC;
 462	goto try_again;
 463}
 464
 465void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 466		    u8 type, u8 code, int offset, __be32 info,
 467		    struct udp_table *udptable)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 468{
 469	struct ipv6_pinfo *np;
 470	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 471	const struct in6_addr *saddr = &hdr->saddr;
 472	const struct in6_addr *daddr = &hdr->daddr;
 473	struct udphdr *uh = (struct udphdr*)(skb->data+offset);
 
 474	struct sock *sk;
 
 475	int err;
 
 476
 477	sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
 478			       saddr, uh->source, inet6_iif(skb), udptable);
 479	if (sk == NULL)
 480		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 481
 
 482	np = inet6_sk(sk);
 483
 484	if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
 
 
 
 
 
 
 
 
 
 
 
 
 
 485		goto out;
 
 486
 487	if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
 
 488		goto out;
 489
 490	if (np->recverr)
 
 
 
 491		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 
 492
 493	sk->sk_err = err;
 494	sk->sk_error_report(sk);
 495out:
 496	sock_put(sk);
 497}
 498
 499static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 500{
 501	int rc;
 502
 503	if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
 504		sock_rps_save_rxhash(sk, skb);
 
 
 
 
 
 505
 506	rc = sock_queue_rcv_skb(sk, skb);
 507	if (rc < 0) {
 508		int is_udplite = IS_UDPLITE(sk);
 509
 510		/* Note that an ENOMEM error is charged twice */
 511		if (rc == -ENOMEM)
 512			UDP6_INC_STATS_BH(sock_net(sk),
 513					UDP_MIB_RCVBUFERRORS, is_udplite);
 514		UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 515		kfree_skb(skb);
 516		return -1;
 517	}
 
 518	return 0;
 519}
 520
 521static __inline__ void udpv6_err(struct sk_buff *skb,
 522				 struct inet6_skb_parm *opt, u8 type,
 523				 u8 code, int offset, __be32 info     )
 524{
 525	__udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 526}
 527
 528static struct static_key udpv6_encap_needed __read_mostly;
 529void udpv6_encap_enable(void)
 530{
 531	if (!static_key_enabled(&udpv6_encap_needed))
 532		static_key_slow_inc(&udpv6_encap_needed);
 533}
 534EXPORT_SYMBOL(udpv6_encap_enable);
 535
 536int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 537{
 538	struct udp_sock *up = udp_sk(sk);
 539	int rc;
 540	int is_udplite = IS_UDPLITE(sk);
 541
 542	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 543		goto drop;
 544
 545	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
 546		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
 547
 548		/*
 549		 * This is an encapsulation socket so pass the skb to
 550		 * the socket's udp_encap_rcv() hook. Otherwise, just
 551		 * fall through and pass this up the UDP socket.
 552		 * up->encap_rcv() returns the following value:
 553		 * =0 if skb was successfully passed to the encap
 554		 *    handler or was discarded by it.
 555		 * >0 if skb should be passed on to UDP.
 556		 * <0 if skb should be resubmitted as proto -N
 557		 */
 558
 559		/* if we're overly short, let UDP handle it */
 560		encap_rcv = ACCESS_ONCE(up->encap_rcv);
 561		if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) {
 562			int ret;
 563
 
 
 
 
 564			ret = encap_rcv(sk, skb);
 565			if (ret <= 0) {
 566				UDP_INC_STATS_BH(sock_net(sk),
 567						 UDP_MIB_INDATAGRAMS,
 568						 is_udplite);
 569				return -ret;
 570			}
 571		}
 572
 573		/* FALLTHROUGH -- it's a UDP Packet */
 574	}
 575
 576	/*
 577	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 578	 */
 579	if ((is_udplite & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 580
 581		if (up->pcrlen == 0) {          /* full coverage was set  */
 582			LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
 583				" %d while full coverage %d requested\n",
 584				UDP_SKB_CB(skb)->cscov, skb->len);
 585			goto drop;
 586		}
 587		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 588			LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
 589						    "too small, need min %d\n",
 590				       UDP_SKB_CB(skb)->cscov, up->pcrlen);
 591			goto drop;
 592		}
 593	}
 594
 595	if (rcu_access_pointer(sk->sk_filter)) {
 596		if (udp_lib_checksum_complete(skb))
 597			goto drop;
 598	}
 599
 600	if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
 601		goto drop;
 602
 
 
 603	skb_dst_drop(skb);
 604
 605	bh_lock_sock(sk);
 606	rc = 0;
 607	if (!sock_owned_by_user(sk))
 608		rc = __udpv6_queue_rcv_skb(sk, skb);
 609	else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
 610		bh_unlock_sock(sk);
 611		goto drop;
 612	}
 613	bh_unlock_sock(sk);
 614
 615	return rc;
 
 616drop:
 617	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 618	atomic_inc(&sk->sk_drops);
 619	kfree_skb(skb);
 620	return -1;
 621}
 622
 623static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
 624				      __be16 loc_port, const struct in6_addr *loc_addr,
 625				      __be16 rmt_port, const struct in6_addr *rmt_addr,
 626				      int dif)
 627{
 628	struct hlist_nulls_node *node;
 629	struct sock *s = sk;
 630	unsigned short num = ntohs(loc_port);
 631
 632	sk_nulls_for_each_from(s, node) {
 633		struct inet_sock *inet = inet_sk(s);
 634
 635		if (!net_eq(sock_net(s), net))
 636			continue;
 
 
 637
 638		if (udp_sk(s)->udp_port_hash == num &&
 639		    s->sk_family == PF_INET6) {
 640			struct ipv6_pinfo *np = inet6_sk(s);
 641			if (inet->inet_dport) {
 642				if (inet->inet_dport != rmt_port)
 643					continue;
 644			}
 645			if (!ipv6_addr_any(&np->daddr) &&
 646			    !ipv6_addr_equal(&np->daddr, rmt_addr))
 647				continue;
 648
 649			if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 650				continue;
 651
 652			if (!ipv6_addr_any(&np->rcv_saddr)) {
 653				if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
 654					continue;
 655			}
 656			if (!inet6_mc_check(s, loc_addr, rmt_addr))
 657				continue;
 658			return s;
 659		}
 660	}
 661	return NULL;
 662}
 663
 664static void flush_stack(struct sock **stack, unsigned int count,
 665			struct sk_buff *skb, unsigned int final)
 
 
 666{
 667	struct sk_buff *skb1 = NULL;
 668	struct sock *sk;
 669	unsigned int i;
 
 670
 671	for (i = 0; i < count; i++) {
 672		sk = stack[i];
 673		if (likely(skb1 == NULL))
 674			skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
 675		if (!skb1) {
 676			atomic_inc(&sk->sk_drops);
 677			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
 678					  IS_UDPLITE(sk));
 679			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
 680					  IS_UDPLITE(sk));
 681		}
 
 
 682
 683		if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
 684			skb1 = NULL;
 685	}
 686	if (unlikely(skb1))
 687		kfree_skb(skb1);
 
 
 
 688}
 
 689/*
 690 * Note: called only from the BH handler context,
 691 * so we don't need to lock the hashes.
 692 */
 693static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 694		const struct in6_addr *saddr, const struct in6_addr *daddr,
 695		struct udp_table *udptable)
 696{
 697	struct sock *sk, *stack[256 / sizeof(struct sock *)];
 698	const struct udphdr *uh = udp_hdr(skb);
 699	struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
 700	int dif;
 701	unsigned int i, count = 0;
 702
 703	spin_lock(&hslot->lock);
 704	sk = sk_nulls_head(&hslot->head);
 705	dif = inet6_iif(skb);
 706	sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
 707	while (sk) {
 708		stack[count++] = sk;
 709		sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
 710				       uh->source, saddr, dif);
 711		if (unlikely(count == ARRAY_SIZE(stack))) {
 712			if (!sk)
 713				break;
 714			flush_stack(stack, count, skb, ~0);
 715			count = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 716		}
 
 
 
 717	}
 718	/*
 719	 * before releasing the lock, we must take reference on sockets
 720	 */
 721	for (i = 0; i < count; i++)
 722		sock_hold(stack[i]);
 723
 724	spin_unlock(&hslot->lock);
 725
 726	if (count) {
 727		flush_stack(stack, count, skb, count - 1);
 
 728
 729		for (i = 0; i < count; i++)
 730			sock_put(stack[i]);
 
 731	} else {
 732		kfree_skb(skb);
 
 
 733	}
 734	return 0;
 735}
 736
 737static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh,
 738				 int proto)
 739{
 740	int err;
 
 741
 742	UDP_SKB_CB(skb)->partial_cov = 0;
 743	UDP_SKB_CB(skb)->cscov = skb->len;
 
 744
 745	if (proto == IPPROTO_UDPLITE) {
 746		err = udplite_checksum_init(skb, uh);
 747		if (err)
 748			return err;
 749	}
 
 
 
 
 
 750
 751	if (uh->check == 0) {
 752		/* RFC 2460 section 8.1 says that we SHOULD log
 753		   this error. Well, it is reasonable.
 754		 */
 755		LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
 756		return 1;
 757	}
 758	if (skb->ip_summed == CHECKSUM_COMPLETE &&
 759	    !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
 760			     skb->len, proto, skb->csum))
 761		skb->ip_summed = CHECKSUM_UNNECESSARY;
 762
 763	if (!skb_csum_unnecessary(skb))
 764		skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
 765							 &ipv6_hdr(skb)->daddr,
 766							 skb->len, proto, 0));
 767
 
 
 
 768	return 0;
 769}
 770
 771int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 772		   int proto)
 773{
 
 774	struct net *net = dev_net(skb->dev);
 
 775	struct sock *sk;
 776	struct udphdr *uh;
 777	const struct in6_addr *saddr, *daddr;
 778	u32 ulen = 0;
 779
 780	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 781		goto discard;
 782
 783	saddr = &ipv6_hdr(skb)->saddr;
 784	daddr = &ipv6_hdr(skb)->daddr;
 785	uh = udp_hdr(skb);
 786
 787	ulen = ntohs(uh->len);
 788	if (ulen > skb->len)
 789		goto short_packet;
 790
 791	if (proto == IPPROTO_UDP) {
 792		/* UDP validates ulen. */
 793
 794		/* Check for jumbo payload */
 795		if (ulen == 0)
 796			ulen = skb->len;
 797
 798		if (ulen < sizeof(*uh))
 799			goto short_packet;
 800
 801		if (ulen < skb->len) {
 802			if (pskb_trim_rcsum(skb, ulen))
 803				goto short_packet;
 804			saddr = &ipv6_hdr(skb)->saddr;
 805			daddr = &ipv6_hdr(skb)->daddr;
 806			uh = udp_hdr(skb);
 807		}
 808	}
 809
 810	if (udp6_csum_init(skb, uh, proto))
 811		goto discard;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 812
 813	/*
 814	 *	Multicast receive code
 815	 */
 816	if (ipv6_addr_is_multicast(daddr))
 817		return __udp6_lib_mcast_deliver(net, skb,
 818				saddr, daddr, udptable);
 819
 820	/* Unicast */
 821
 822	/*
 823	 * check socket cache ... must talk to Alan about his plans
 824	 * for sock caches... i'll skip this for now.
 825	 */
 826	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
 827	if (sk != NULL) {
 828		int ret = udpv6_queue_rcv_skb(sk, skb);
 829		sock_put(sk);
 830
 831		/* a return value > 0 means to resubmit the input, but
 832		 * it wants the return to be -protocol, or 0
 833		 */
 834		if (ret > 0)
 835			return -ret;
 836
 837		return 0;
 838	}
 839
 840	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 841		goto discard;
 842
 843	if (udp_lib_checksum_complete(skb))
 844		goto discard;
 845
 846	UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
 847	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 848
 849	kfree_skb(skb);
 850	return 0;
 851
 852short_packet:
 853	LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
 854		       proto == IPPROTO_UDPLITE ? "-Lite" : "",
 855		       saddr,
 856		       ntohs(uh->source),
 857		       ulen,
 858		       skb->len,
 859		       daddr,
 860		       ntohs(uh->dest));
 861
 
 
 862discard:
 863	UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
 864	kfree_skb(skb);
 865	return 0;
 866}
 867
 868static __inline__ int udpv6_rcv(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 869{
 870	return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
 871}
 872
 873/*
 874 * Throw away all pending data and cancel the corking. Socket is locked.
 875 */
 876static void udp_v6_flush_pending_frames(struct sock *sk)
 877{
 878	struct udp_sock *up = udp_sk(sk);
 879
 880	if (up->pending == AF_INET)
 881		udp_flush_pending_frames(sk);
 882	else if (up->pending) {
 883		up->len = 0;
 884		up->pending = 0;
 885		ip6_flush_pending_frames(sk);
 886	}
 887}
 888
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 889/**
 890 * 	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
 891 * 	@sk: 	socket we are sending on
 892 * 	@skb: 	sk_buff containing the filled-in UDP header
 893 * 	        (checksum field must be zeroed out)
 
 
 
 894 */
 895static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
 896				 const struct in6_addr *saddr,
 897				 const struct in6_addr *daddr, int len)
 898{
 899	unsigned int offset;
 900	struct udphdr *uh = udp_hdr(skb);
 
 901	__wsum csum = 0;
 902
 903	if (skb_queue_len(&sk->sk_write_queue) == 1) {
 904		/* Only one fragment on the socket.  */
 905		skb->csum_start = skb_transport_header(skb) - skb->head;
 906		skb->csum_offset = offsetof(struct udphdr, check);
 907		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
 908	} else {
 909		/*
 910		 * HW-checksum won't work as there are two or more
 911		 * fragments on the socket so that all csums of sk_buffs
 912		 * should be together
 913		 */
 914		offset = skb_transport_offset(skb);
 915		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
 
 916
 917		skb->ip_summed = CHECKSUM_NONE;
 918
 919		skb_queue_walk(&sk->sk_write_queue, skb) {
 920			csum = csum_add(csum, skb->csum);
 921		}
 922
 923		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
 924					    csum);
 925		if (uh->check == 0)
 926			uh->check = CSUM_MANGLED_0;
 927	}
 928}
 929
 930/*
 931 *	Sending
 932 */
 933
 934static int udp_v6_push_pending_frames(struct sock *sk)
 
 935{
 936	struct sk_buff *skb;
 937	struct udphdr *uh;
 938	struct udp_sock  *up = udp_sk(sk);
 939	struct inet_sock *inet = inet_sk(sk);
 940	struct flowi6 *fl6 = &inet->cork.fl.u.ip6;
 941	int err = 0;
 942	int is_udplite = IS_UDPLITE(sk);
 943	__wsum csum = 0;
 944
 945	/* Grab the skbuff where UDP header space exists. */
 946	if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 947		goto out;
 948
 949	/*
 950	 * Create a UDP header
 951	 */
 952	uh = udp_hdr(skb);
 953	uh->source = fl6->fl6_sport;
 954	uh->dest = fl6->fl6_dport;
 955	uh->len = htons(up->len);
 956	uh->check = 0;
 957
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 958	if (is_udplite)
 959		csum = udplite_csum_outgoing(sk, skb);
 960	else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
 961		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
 962				     up->len);
 
 
 
 963		goto send;
 964	} else
 965		csum = udp_csum_outgoing(sk, skb);
 966
 967	/* add protocol-dependent pseudo-header */
 968	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
 969				    up->len, fl6->flowi6_proto, csum);
 970	if (uh->check == 0)
 971		uh->check = CSUM_MANGLED_0;
 972
 973send:
 974	err = ip6_push_pending_frames(sk);
 975	if (err) {
 976		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
 977			UDP6_INC_STATS_USER(sock_net(sk),
 978					    UDP_MIB_SNDBUFERRORS, is_udplite);
 979			err = 0;
 980		}
 981	} else
 982		UDP6_INC_STATS_USER(sock_net(sk),
 983				    UDP_MIB_OUTDATAGRAMS, is_udplite);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 984out:
 985	up->len = 0;
 986	up->pending = 0;
 987	return err;
 988}
 989
 990int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 991		  struct msghdr *msg, size_t len)
 992{
 993	struct ipv6_txoptions opt_space;
 994	struct udp_sock *up = udp_sk(sk);
 995	struct inet_sock *inet = inet_sk(sk);
 996	struct ipv6_pinfo *np = inet6_sk(sk);
 997	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
 998	struct in6_addr *daddr, *final_p, final;
 999	struct ipv6_txoptions *opt = NULL;
 
1000	struct ip6_flowlabel *flowlabel = NULL;
1001	struct flowi6 fl6;
1002	struct dst_entry *dst;
 
1003	int addr_len = msg->msg_namelen;
 
1004	int ulen = len;
1005	int hlimit = -1;
1006	int tclass = -1;
1007	int dontfrag = -1;
1008	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1009	int err;
1010	int connected = 0;
1011	int is_udplite = IS_UDPLITE(sk);
1012	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1013
 
 
 
 
 
1014	/* destination address check */
1015	if (sin6) {
1016		if (addr_len < offsetof(struct sockaddr, sa_data))
1017			return -EINVAL;
1018
1019		switch (sin6->sin6_family) {
1020		case AF_INET6:
1021			if (addr_len < SIN6_LEN_RFC2133)
1022				return -EINVAL;
1023			daddr = &sin6->sin6_addr;
 
 
 
 
1024			break;
1025		case AF_INET:
1026			goto do_udp_sendmsg;
1027		case AF_UNSPEC:
1028			msg->msg_name = sin6 = NULL;
1029			msg->msg_namelen = addr_len = 0;
1030			daddr = NULL;
1031			break;
1032		default:
1033			return -EINVAL;
1034		}
1035	} else if (!up->pending) {
1036		if (sk->sk_state != TCP_ESTABLISHED)
1037			return -EDESTADDRREQ;
1038		daddr = &np->daddr;
1039	} else
1040		daddr = NULL;
1041
1042	if (daddr) {
1043		if (ipv6_addr_v4mapped(daddr)) {
1044			struct sockaddr_in sin;
1045			sin.sin_family = AF_INET;
1046			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1047			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1048			msg->msg_name = &sin;
1049			msg->msg_namelen = sizeof(sin);
1050do_udp_sendmsg:
1051			if (__ipv6_only_sock(sk))
1052				return -ENETUNREACH;
1053			return udp_sendmsg(iocb, sk, msg, len);
1054		}
1055	}
1056
1057	if (up->pending == AF_INET)
1058		return udp_sendmsg(iocb, sk, msg, len);
1059
1060	/* Rough check on arithmetic overflow,
1061	   better check is made in ip6_append_data().
1062	   */
1063	if (len > INT_MAX - sizeof(struct udphdr))
1064		return -EMSGSIZE;
1065
 
1066	if (up->pending) {
1067		/*
1068		 * There are pending frames.
1069		 * The socket lock must be held while it's corked.
1070		 */
1071		lock_sock(sk);
1072		if (likely(up->pending)) {
1073			if (unlikely(up->pending != AF_INET6)) {
1074				release_sock(sk);
1075				return -EAFNOSUPPORT;
1076			}
1077			dst = NULL;
1078			goto do_append_data;
1079		}
1080		release_sock(sk);
1081	}
1082	ulen += sizeof(struct udphdr);
1083
1084	memset(&fl6, 0, sizeof(fl6));
1085
1086	if (sin6) {
1087		if (sin6->sin6_port == 0)
1088			return -EINVAL;
1089
1090		fl6.fl6_dport = sin6->sin6_port;
1091		daddr = &sin6->sin6_addr;
1092
1093		if (np->sndflow) {
1094			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1095			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1096				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1097				if (flowlabel == NULL)
1098					return -EINVAL;
1099				daddr = &flowlabel->dst;
1100			}
1101		}
1102
1103		/*
1104		 * Otherwise it will be difficult to maintain
1105		 * sk->sk_dst_cache.
1106		 */
1107		if (sk->sk_state == TCP_ESTABLISHED &&
1108		    ipv6_addr_equal(daddr, &np->daddr))
1109			daddr = &np->daddr;
1110
1111		if (addr_len >= sizeof(struct sockaddr_in6) &&
1112		    sin6->sin6_scope_id &&
1113		    ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
1114			fl6.flowi6_oif = sin6->sin6_scope_id;
1115	} else {
1116		if (sk->sk_state != TCP_ESTABLISHED)
1117			return -EDESTADDRREQ;
1118
1119		fl6.fl6_dport = inet->inet_dport;
1120		daddr = &np->daddr;
1121		fl6.flowlabel = np->flow_label;
1122		connected = 1;
1123	}
1124
1125	if (!fl6.flowi6_oif)
1126		fl6.flowi6_oif = sk->sk_bound_dev_if;
1127
1128	if (!fl6.flowi6_oif)
1129		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1130
1131	fl6.flowi6_mark = sk->sk_mark;
 
1132
1133	if (msg->msg_controllen) {
1134		opt = &opt_space;
1135		memset(opt, 0, sizeof(struct ipv6_txoptions));
1136		opt->tot_len = sizeof(*opt);
 
1137
1138		err = datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1139					&hlimit, &tclass, &dontfrag);
 
 
1140		if (err < 0) {
1141			fl6_sock_release(flowlabel);
1142			return err;
1143		}
1144		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1145			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1146			if (flowlabel == NULL)
1147				return -EINVAL;
1148		}
1149		if (!(opt->opt_nflen|opt->opt_flen))
1150			opt = NULL;
1151		connected = 0;
 
 
 
 
1152	}
1153	if (opt == NULL)
1154		opt = np->opt;
1155	if (flowlabel)
1156		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1157	opt = ipv6_fixup_options(&opt_space, opt);
 
1158
1159	fl6.flowi6_proto = sk->sk_protocol;
1160	if (!ipv6_addr_any(daddr))
1161		fl6.daddr = *daddr;
1162	else
1163		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1164	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1165		fl6.saddr = np->saddr;
1166	fl6.fl6_sport = inet->inet_sport;
1167
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1168	final_p = fl6_update_dst(&fl6, opt, &final);
1169	if (final_p)
1170		connected = 0;
1171
1172	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1173		fl6.flowi6_oif = np->mcast_oif;
1174		connected = 0;
1175	} else if (!fl6.flowi6_oif)
1176		fl6.flowi6_oif = np->ucast_oif;
1177
1178	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1179
1180	dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, true);
 
 
 
 
 
1181	if (IS_ERR(dst)) {
1182		err = PTR_ERR(dst);
1183		dst = NULL;
1184		goto out;
1185	}
1186
1187	if (hlimit < 0) {
1188		if (ipv6_addr_is_multicast(&fl6.daddr))
1189			hlimit = np->mcast_hops;
1190		else
1191			hlimit = np->hop_limit;
1192		if (hlimit < 0)
1193			hlimit = ip6_dst_hoplimit(dst);
1194	}
1195
1196	if (tclass < 0)
1197		tclass = np->tclass;
1198
1199	if (dontfrag < 0)
1200		dontfrag = np->dontfrag;
1201
1202	if (msg->msg_flags&MSG_CONFIRM)
1203		goto do_confirm;
1204back_from_confirm:
1205
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1206	lock_sock(sk);
1207	if (unlikely(up->pending)) {
1208		/* The socket is already corked while preparing it. */
1209		/* ... which is an evident application bug. --ANK */
1210		release_sock(sk);
1211
1212		LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1213		err = -EINVAL;
1214		goto out;
1215	}
1216
1217	up->pending = AF_INET6;
1218
1219do_append_data:
 
 
1220	up->len += ulen;
1221	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1222	err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1223		sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1224		(struct rt6_info*)dst,
1225		corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1226	if (err)
1227		udp_v6_flush_pending_frames(sk);
1228	else if (!corkreq)
1229		err = udp_v6_push_pending_frames(sk);
1230	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1231		up->pending = 0;
1232
1233	if (dst) {
1234		if (connected) {
1235			ip6_dst_store(sk, dst,
1236				      ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
1237				      &np->daddr : NULL,
1238#ifdef CONFIG_IPV6_SUBTREES
1239				      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1240				      &np->saddr :
1241#endif
1242				      NULL);
1243		} else {
1244			dst_release(dst);
1245		}
1246		dst = NULL;
1247	}
1248
1249	if (err > 0)
1250		err = np->recverr ? net_xmit_errno(err) : 0;
1251	release_sock(sk);
 
1252out:
1253	dst_release(dst);
 
1254	fl6_sock_release(flowlabel);
 
1255	if (!err)
1256		return len;
1257	/*
1258	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1259	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1260	 * we don't have a good statistic (IpOutDiscards but it can be too many
1261	 * things).  We could add another new stat but at least for now that
1262	 * seems like overkill.
1263	 */
1264	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1265		UDP6_INC_STATS_USER(sock_net(sk),
1266				UDP_MIB_SNDBUFERRORS, is_udplite);
1267	}
1268	return err;
1269
1270do_confirm:
1271	dst_confirm(dst);
 
1272	if (!(msg->msg_flags&MSG_PROBE) || len)
1273		goto back_from_confirm;
1274	err = 0;
1275	goto out;
1276}
1277
1278void udpv6_destroy_sock(struct sock *sk)
1279{
 
1280	lock_sock(sk);
1281	udp_v6_flush_pending_frames(sk);
1282	release_sock(sk);
1283
 
 
 
 
 
 
 
 
 
 
 
1284	inet6_destroy_sock(sk);
1285}
1286
1287/*
1288 *	Socket option code for UDP
1289 */
1290int udpv6_setsockopt(struct sock *sk, int level, int optname,
1291		     char __user *optval, unsigned int optlen)
1292{
1293	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1294		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
 
1295					  udp_v6_push_pending_frames);
1296	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1297}
1298
1299#ifdef CONFIG_COMPAT
1300int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1301			    char __user *optval, unsigned int optlen)
1302{
1303	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1304		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1305					  udp_v6_push_pending_frames);
1306	return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1307}
1308#endif
1309
1310int udpv6_getsockopt(struct sock *sk, int level, int optname,
1311		     char __user *optval, int __user *optlen)
1312{
1313	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1314		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1315	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1316}
1317
1318#ifdef CONFIG_COMPAT
1319int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1320			    char __user *optval, int __user *optlen)
1321{
1322	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1323		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1324	return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1325}
1326#endif
1327
1328static int udp6_ufo_send_check(struct sk_buff *skb)
1329{
1330	const struct ipv6hdr *ipv6h;
1331	struct udphdr *uh;
1332
1333	if (!pskb_may_pull(skb, sizeof(*uh)))
1334		return -EINVAL;
1335
1336	ipv6h = ipv6_hdr(skb);
1337	uh = udp_hdr(skb);
1338
1339	uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
1340				     IPPROTO_UDP, 0);
1341	skb->csum_start = skb_transport_header(skb) - skb->head;
1342	skb->csum_offset = offsetof(struct udphdr, check);
1343	skb->ip_summed = CHECKSUM_PARTIAL;
1344	return 0;
1345}
1346
1347static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb,
1348	netdev_features_t features)
1349{
1350	struct sk_buff *segs = ERR_PTR(-EINVAL);
1351	unsigned int mss;
1352	unsigned int unfrag_ip6hlen, unfrag_len;
1353	struct frag_hdr *fptr;
1354	u8 *mac_start, *prevhdr;
1355	u8 nexthdr;
1356	u8 frag_hdr_sz = sizeof(struct frag_hdr);
1357	int offset;
1358	__wsum csum;
1359
1360	mss = skb_shinfo(skb)->gso_size;
1361	if (unlikely(skb->len <= mss))
1362		goto out;
1363
1364	if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
1365		/* Packet is from an untrusted source, reset gso_segs. */
1366		int type = skb_shinfo(skb)->gso_type;
1367
1368		if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
1369			     !(type & (SKB_GSO_UDP))))
1370			goto out;
1371
1372		skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
1373
1374		segs = NULL;
1375		goto out;
1376	}
1377
1378	/* Do software UFO. Complete and fill in the UDP checksum as HW cannot
1379	 * do checksum of UDP packets sent as multiple IP fragments.
1380	 */
1381	offset = skb_checksum_start_offset(skb);
1382	csum = skb_checksum(skb, offset, skb->len - offset, 0);
1383	offset += skb->csum_offset;
1384	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
1385	skb->ip_summed = CHECKSUM_NONE;
1386
1387	/* Check if there is enough headroom to insert fragment header. */
1388	if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) &&
1389	    pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
1390		goto out;
1391
1392	/* Find the unfragmentable header and shift it left by frag_hdr_sz
1393	 * bytes to insert fragment header.
1394	 */
1395	unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
1396	nexthdr = *prevhdr;
1397	*prevhdr = NEXTHDR_FRAGMENT;
1398	unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
1399		     unfrag_ip6hlen;
1400	mac_start = skb_mac_header(skb);
1401	memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
1402
1403	skb->mac_header -= frag_hdr_sz;
1404	skb->network_header -= frag_hdr_sz;
1405
1406	fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
1407	fptr->nexthdr = nexthdr;
1408	fptr->reserved = 0;
1409	ipv6_select_ident(fptr, (struct rt6_info *)skb_dst(skb));
1410
1411	/* Fragment the skb. ipv6 header and the remaining fields of the
1412	 * fragment header are updated in ipv6_gso_segment()
1413	 */
1414	segs = skb_segment(skb, features);
1415
1416out:
1417	return segs;
1418}
1419
1420static const struct inet6_protocol udpv6_protocol = {
1421	.handler	=	udpv6_rcv,
1422	.err_handler	=	udpv6_err,
1423	.gso_send_check =	udp6_ufo_send_check,
1424	.gso_segment	=	udp6_ufo_fragment,
1425	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1426};
1427
1428/* ------------------------------------------------------------------------ */
1429#ifdef CONFIG_PROC_FS
1430
1431static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1432{
1433	struct inet_sock *inet = inet_sk(sp);
1434	struct ipv6_pinfo *np = inet6_sk(sp);
1435	const struct in6_addr *dest, *src;
1436	__u16 destp, srcp;
1437
1438	dest  = &np->daddr;
1439	src   = &np->rcv_saddr;
1440	destp = ntohs(inet->inet_dport);
1441	srcp  = ntohs(inet->inet_sport);
1442	seq_printf(seq,
1443		   "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1444		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d\n",
1445		   bucket,
1446		   src->s6_addr32[0], src->s6_addr32[1],
1447		   src->s6_addr32[2], src->s6_addr32[3], srcp,
1448		   dest->s6_addr32[0], dest->s6_addr32[1],
1449		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
1450		   sp->sk_state,
1451		   sk_wmem_alloc_get(sp),
1452		   sk_rmem_alloc_get(sp),
1453		   0, 0L, 0,
1454		   sock_i_uid(sp), 0,
1455		   sock_i_ino(sp),
1456		   atomic_read(&sp->sk_refcnt), sp,
1457		   atomic_read(&sp->sk_drops));
1458}
1459
1460int udp6_seq_show(struct seq_file *seq, void *v)
1461{
1462	if (v == SEQ_START_TOKEN)
1463		seq_printf(seq,
1464			   "  sl  "
1465			   "local_address                         "
1466			   "remote_address                        "
1467			   "st tx_queue rx_queue tr tm->when retrnsmt"
1468			   "   uid  timeout inode ref pointer drops\n");
1469	else
1470		udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
 
1471	return 0;
1472}
1473
1474static const struct file_operations udp6_afinfo_seq_fops = {
1475	.owner    = THIS_MODULE,
1476	.open     = udp_seq_open,
1477	.read     = seq_read,
1478	.llseek   = seq_lseek,
1479	.release  = seq_release_net
1480};
 
1481
1482static struct udp_seq_afinfo udp6_seq_afinfo = {
1483	.name		= "udp6",
1484	.family		= AF_INET6,
1485	.udp_table	= &udp_table,
1486	.seq_fops	= &udp6_afinfo_seq_fops,
1487	.seq_ops	= {
1488		.show		= udp6_seq_show,
1489	},
1490};
1491
1492int __net_init udp6_proc_init(struct net *net)
1493{
1494	return udp_proc_register(net, &udp6_seq_afinfo);
 
 
 
1495}
1496
1497void udp6_proc_exit(struct net *net) {
1498	udp_proc_unregister(net, &udp6_seq_afinfo);
 
1499}
1500#endif /* CONFIG_PROC_FS */
1501
1502/* ------------------------------------------------------------------------ */
1503
1504struct proto udpv6_prot = {
1505	.name		   = "UDPv6",
1506	.owner		   = THIS_MODULE,
1507	.close		   = udp_lib_close,
1508	.connect	   = ip6_datagram_connect,
1509	.disconnect	   = udp_disconnect,
1510	.ioctl		   = udp_ioctl,
1511	.destroy	   = udpv6_destroy_sock,
1512	.setsockopt	   = udpv6_setsockopt,
1513	.getsockopt	   = udpv6_getsockopt,
1514	.sendmsg	   = udpv6_sendmsg,
1515	.recvmsg	   = udpv6_recvmsg,
1516	.backlog_rcv	   = __udpv6_queue_rcv_skb,
1517	.hash		   = udp_lib_hash,
1518	.unhash		   = udp_lib_unhash,
1519	.rehash		   = udp_v6_rehash,
1520	.get_port	   = udp_v6_get_port,
1521	.memory_allocated  = &udp_memory_allocated,
1522	.sysctl_mem	   = sysctl_udp_mem,
1523	.sysctl_wmem	   = &sysctl_udp_wmem_min,
1524	.sysctl_rmem	   = &sysctl_udp_rmem_min,
1525	.obj_size	   = sizeof(struct udp6_sock),
1526	.slab_flags	   = SLAB_DESTROY_BY_RCU,
1527	.h.udp_table	   = &udp_table,
1528#ifdef CONFIG_COMPAT
1529	.compat_setsockopt = compat_udpv6_setsockopt,
1530	.compat_getsockopt = compat_udpv6_getsockopt,
1531#endif
1532	.clear_sk	   = sk_prot_clear_portaddr_nulls,
1533};
1534
1535static struct inet_protosw udpv6_protosw = {
1536	.type =      SOCK_DGRAM,
1537	.protocol =  IPPROTO_UDP,
1538	.prot =      &udpv6_prot,
1539	.ops =       &inet6_dgram_ops,
1540	.no_check =  UDP_CSUM_DEFAULT,
1541	.flags =     INET_PROTOSW_PERMANENT,
1542};
1543
1544
1545int __init udpv6_init(void)
1546{
1547	int ret;
1548
1549	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1550	if (ret)
1551		goto out;
1552
1553	ret = inet6_register_protosw(&udpv6_protosw);
1554	if (ret)
1555		goto out_udpv6_protocol;
1556out:
1557	return ret;
1558
1559out_udpv6_protocol:
1560	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1561	goto out;
1562}
1563
1564void udpv6_exit(void)
1565{
1566	inet6_unregister_protosw(&udpv6_protosw);
1567	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1568}