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v6.8
   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/bpf-cgroup.h>
  21#include <linux/errno.h>
  22#include <linux/types.h>
  23#include <linux/socket.h>
  24#include <linux/sockios.h>
  25#include <linux/net.h>
  26#include <linux/in6.h>
  27#include <linux/netdevice.h>
  28#include <linux/if_arp.h>
  29#include <linux/ipv6.h>
  30#include <linux/icmpv6.h>
  31#include <linux/init.h>
  32#include <linux/module.h>
  33#include <linux/skbuff.h>
  34#include <linux/slab.h>
  35#include <linux/uaccess.h>
  36#include <linux/indirect_call_wrapper.h>
  37
  38#include <net/addrconf.h>
  39#include <net/ndisc.h>
  40#include <net/protocol.h>
  41#include <net/transp_v6.h>
  42#include <net/ip6_route.h>
  43#include <net/raw.h>
  44#include <net/seg6.h>
  45#include <net/tcp_states.h>
  46#include <net/ip6_checksum.h>
  47#include <net/ip6_tunnel.h>
  48#include <trace/events/udp.h>
  49#include <net/xfrm.h>
  50#include <net/inet_hashtables.h>
  51#include <net/inet6_hashtables.h>
  52#include <net/busy_poll.h>
  53#include <net/sock_reuseport.h>
  54#include <net/gro.h>
  55
  56#include <linux/proc_fs.h>
  57#include <linux/seq_file.h>
  58#include <trace/events/skb.h>
  59#include "udp_impl.h"
  60
  61static void udpv6_destruct_sock(struct sock *sk)
  62{
  63	udp_destruct_common(sk);
  64	inet6_sock_destruct(sk);
  65}
  66
  67int udpv6_init_sock(struct sock *sk)
  68{
  69	udp_lib_init_sock(sk);
  70	sk->sk_destruct = udpv6_destruct_sock;
  71	set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
  72	return 0;
  73}
  74
  75INDIRECT_CALLABLE_SCOPE
  76u32 udp6_ehashfn(const struct net *net,
  77		 const struct in6_addr *laddr,
  78		 const u16 lport,
  79		 const struct in6_addr *faddr,
  80		 const __be16 fport)
  81{
  82	static u32 udp6_ehash_secret __read_mostly;
  83	static u32 udp_ipv6_hash_secret __read_mostly;
  84
  85	u32 lhash, fhash;
  86
  87	net_get_random_once(&udp6_ehash_secret,
  88			    sizeof(udp6_ehash_secret));
  89	net_get_random_once(&udp_ipv6_hash_secret,
  90			    sizeof(udp_ipv6_hash_secret));
  91
  92	lhash = (__force u32)laddr->s6_addr32[3];
  93	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
  94
  95	return __inet6_ehashfn(lhash, lport, fhash, fport,
  96			       udp6_ehash_secret + net_hash_mix(net));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  97}
  98
 
  99int udp_v6_get_port(struct sock *sk, unsigned short snum)
 100{
 101	unsigned int hash2_nulladdr =
 102		ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
 103	unsigned int hash2_partial =
 104		ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
 105
 106	/* precompute partial secondary hash */
 107	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
 108	return udp_lib_get_port(sk, snum, hash2_nulladdr);
 109}
 110
 111void udp_v6_rehash(struct sock *sk)
 112{
 113	u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
 114					  &sk->sk_v6_rcv_saddr,
 115					  inet_sk(sk)->inet_num);
 116
 117	udp_lib_rehash(sk, new_hash);
 118}
 119
 120static int compute_score(struct sock *sk, struct net *net,
 121			 const struct in6_addr *saddr, __be16 sport,
 122			 const struct in6_addr *daddr, unsigned short hnum,
 123			 int dif, int sdif)
 124{
 125	int bound_dev_if, score;
 126	struct inet_sock *inet;
 127	bool dev_match;
 128
 129	if (!net_eq(sock_net(sk), net) ||
 130	    udp_sk(sk)->udp_port_hash != hnum ||
 131	    sk->sk_family != PF_INET6)
 132		return -1;
 133
 134	if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 135		return -1;
 136
 137	score = 0;
 138	inet = inet_sk(sk);
 139
 140	if (inet->inet_dport) {
 141		if (inet->inet_dport != sport)
 142			return -1;
 143		score++;
 
 
 
 
 
 
 
 
 
 144	}
 
 
 145
 146	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 147		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 
 
 
 
 
 
 
 
 
 
 
 148			return -1;
 149		score++;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 150	}
 151
 152	bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
 153	dev_match = udp_sk_bound_dev_eq(net, bound_dev_if, dif, sdif);
 154	if (!dev_match)
 155		return -1;
 156	if (bound_dev_if)
 157		score++;
 158
 159	if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
 160		score++;
 161
 162	return score;
 163}
 164
 165/* called with rcu_read_lock() */
 
 166static struct sock *udp6_lib_lookup2(struct net *net,
 167		const struct in6_addr *saddr, __be16 sport,
 168		const struct in6_addr *daddr, unsigned int hnum,
 169		int dif, int sdif, struct udp_hslot *hslot2,
 170		struct sk_buff *skb)
 171{
 172	struct sock *sk, *result;
 173	int score, badness;
 
 
 174
 
 175	result = NULL;
 176	badness = -1;
 177	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
 178		score = compute_score(sk, net, saddr, sport,
 179				      daddr, hnum, dif, sdif);
 180		if (score > badness) {
 
 181			badness = score;
 182
 183			if (sk->sk_state == TCP_ESTABLISHED) {
 184				result = sk;
 185				continue;
 186			}
 187
 188			result = inet6_lookup_reuseport(net, sk, skb, sizeof(struct udphdr),
 189							saddr, sport, daddr, hnum, udp6_ehashfn);
 190			if (!result) {
 
 191				result = sk;
 192				continue;
 193			}
 194
 195			/* Fall back to scoring if group has connections */
 196			if (!reuseport_has_conns(sk))
 197				return result;
 198
 199			/* Reuseport logic returned an error, keep original score. */
 200			if (IS_ERR(result))
 201				continue;
 202
 203			badness = compute_score(sk, net, saddr, sport,
 204						daddr, hnum, dif, sdif);
 
 
 
 
 
 
 205		}
 206	}
 207	return result;
 208}
 209
 210/* rcu_read_lock() must be held */
 211struct sock *__udp6_lib_lookup(struct net *net,
 212			       const struct in6_addr *saddr, __be16 sport,
 213			       const struct in6_addr *daddr, __be16 dport,
 214			       int dif, int sdif, struct udp_table *udptable,
 215			       struct sk_buff *skb)
 216{
 
 
 217	unsigned short hnum = ntohs(dport);
 218	unsigned int hash2, slot2;
 219	struct udp_hslot *hslot2;
 220	struct sock *result, *sk;
 221
 222	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
 223	slot2 = hash2 & udptable->mask;
 224	hslot2 = &udptable->hash2[slot2];
 225
 226	/* Lookup connected or non-wildcard sockets */
 227	result = udp6_lib_lookup2(net, saddr, sport,
 228				  daddr, hnum, dif, sdif,
 229				  hslot2, skb);
 230	if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
 231		goto done;
 232
 233	/* Lookup redirect from BPF */
 234	if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
 235	    udptable == net->ipv4.udp_table) {
 236		sk = inet6_lookup_run_sk_lookup(net, IPPROTO_UDP, skb, sizeof(struct udphdr),
 237						saddr, sport, daddr, hnum, dif,
 238						udp6_ehashfn);
 239		if (sk) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 240			result = sk;
 241			goto done;
 
 
 
 
 
 
 
 
 
 
 
 242		}
 243	}
 
 
 
 
 
 
 
 244
 245	/* Got non-wildcard socket or error on first lookup */
 246	if (result)
 247		goto done;
 248
 249	/* Lookup wildcard sockets */
 250	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
 251	slot2 = hash2 & udptable->mask;
 252	hslot2 = &udptable->hash2[slot2];
 253
 254	result = udp6_lib_lookup2(net, saddr, sport,
 255				  &in6addr_any, hnum, dif, sdif,
 256				  hslot2, skb);
 257done:
 258	if (IS_ERR(result))
 259		return NULL;
 260	return result;
 261}
 262EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
 263
 264static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 265					  __be16 sport, __be16 dport,
 266					  struct udp_table *udptable)
 267{
 
 268	const struct ipv6hdr *iph = ipv6_hdr(skb);
 269
 270	return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
 
 
 271				 &iph->daddr, dport, inet6_iif(skb),
 272				 inet6_sdif(skb), udptable, skb);
 273}
 274
 275struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
 276				 __be16 sport, __be16 dport)
 277{
 278	const struct ipv6hdr *iph = ipv6_hdr(skb);
 279	struct net *net = dev_net(skb->dev);
 280	int iif, sdif;
 281
 282	inet6_get_iif_sdif(skb, &iif, &sdif);
 283
 284	return __udp6_lib_lookup(net, &iph->saddr, sport,
 285				 &iph->daddr, dport, iif,
 286				 sdif, net->ipv4.udp_table, NULL);
 287}
 288
 289/* Must be called under rcu_read_lock().
 290 * Does increment socket refcount.
 291 */
 292#if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
 293struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 294			     const struct in6_addr *daddr, __be16 dport, int dif)
 295{
 296	struct sock *sk;
 297
 298	sk =  __udp6_lib_lookup(net, saddr, sport, daddr, dport,
 299				dif, 0, net->ipv4.udp_table, NULL);
 300	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
 301		sk = NULL;
 302	return sk;
 303}
 304EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 305#endif
 306
 307/* do not use the scratch area len for jumbogram: their length execeeds the
 308 * scratch area space; note that the IP6CB flags is still in the first
 309 * cacheline, so checking for jumbograms is cheap
 310 */
 311static int udp6_skb_len(struct sk_buff *skb)
 312{
 313	return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
 314}
 315
 316/*
 317 *	This should be easy, if there is something there we
 318 *	return it, otherwise we block.
 319 */
 320
 321int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 322		  int flags, int *addr_len)
 
 323{
 324	struct ipv6_pinfo *np = inet6_sk(sk);
 325	struct inet_sock *inet = inet_sk(sk);
 326	struct sk_buff *skb;
 327	unsigned int ulen, copied;
 328	int off, err, peeking = flags & MSG_PEEK;
 
 329	int is_udplite = IS_UDPLITE(sk);
 330	struct udp_mib __percpu *mib;
 331	bool checksum_valid = false;
 332	int is_udp4;
 
 333
 334	if (flags & MSG_ERRQUEUE)
 335		return ipv6_recv_error(sk, msg, len, addr_len);
 336
 337	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 338		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 339
 340try_again:
 341	off = sk_peek_offset(sk, flags);
 342	skb = __skb_recv_udp(sk, flags, &off, &err);
 343	if (!skb)
 344		return err;
 345
 346	ulen = udp6_skb_len(skb);
 347	copied = len;
 348	if (copied > ulen - off)
 349		copied = ulen - off;
 350	else if (copied < ulen)
 351		msg->msg_flags |= MSG_TRUNC;
 352
 353	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 354	mib = __UDPX_MIB(sk, is_udp4);
 355
 356	/*
 357	 * If checksum is needed at all, try to do it while copying the
 358	 * data.  If the data is truncated, or if we only want a partial
 359	 * coverage checksum (UDP-Lite), do it before the copy.
 360	 */
 361
 362	if (copied < ulen || peeking ||
 363	    (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
 364		checksum_valid = udp_skb_csum_unnecessary(skb) ||
 365				!__udp_lib_checksum_complete(skb);
 366		if (!checksum_valid)
 367			goto csum_copy_err;
 368	}
 369
 370	if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
 371		if (udp_skb_is_linear(skb))
 372			err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
 373		else
 374			err = skb_copy_datagram_msg(skb, off, msg, copied);
 375	} else {
 376		err = skb_copy_and_csum_datagram_msg(skb, off, msg);
 377		if (err == -EINVAL)
 378			goto csum_copy_err;
 379	}
 380	if (unlikely(err)) {
 381		if (!peeking) {
 
 382			atomic_inc(&sk->sk_drops);
 383			SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 384		}
 385		kfree_skb(skb);
 386		return err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 387	}
 388	if (!peeking)
 389		SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS);
 390
 391	sock_recv_cmsgs(msg, sk, skb);
 392
 393	/* Copy the address. */
 394	if (msg->msg_name) {
 395		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 396		sin6->sin6_family = AF_INET6;
 397		sin6->sin6_port = udp_hdr(skb)->source;
 398		sin6->sin6_flowinfo = 0;
 399
 400		if (is_udp4) {
 401			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 402					       &sin6->sin6_addr);
 403			sin6->sin6_scope_id = 0;
 404		} else {
 405			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 406			sin6->sin6_scope_id =
 407				ipv6_iface_scope_id(&sin6->sin6_addr,
 408						    inet6_iif(skb));
 409		}
 410		*addr_len = sizeof(*sin6);
 411
 412		BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk,
 413						      (struct sockaddr *)sin6,
 414						      addr_len);
 415	}
 416
 417	if (udp_test_bit(GRO_ENABLED, sk))
 418		udp_cmsg_recv(msg, sk, skb);
 419
 420	if (np->rxopt.all)
 421		ip6_datagram_recv_common_ctl(sk, msg, skb);
 422
 423	if (is_udp4) {
 424		if (inet_cmsg_flags(inet))
 425			ip_cmsg_recv_offset(msg, sk, skb,
 426					    sizeof(struct udphdr), off);
 427	} else {
 428		if (np->rxopt.all)
 429			ip6_datagram_recv_specific_ctl(sk, msg, skb);
 430	}
 431
 432	err = copied;
 433	if (flags & MSG_TRUNC)
 434		err = ulen;
 435
 436	skb_consume_udp(sk, skb, peeking ? -err : err);
 
 
 437	return err;
 438
 439csum_copy_err:
 440	if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
 441				 udp_skb_destructor)) {
 442		SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS);
 443		SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 
 
 
 
 
 
 
 
 
 444	}
 445	kfree_skb(skb);
 
 
 
 446
 447	/* starting over for a new packet, but check if we need to yield */
 448	cond_resched();
 449	msg->msg_flags &= ~MSG_TRUNC;
 450	goto try_again;
 451}
 452
 453DEFINE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
 454void udpv6_encap_enable(void)
 455{
 456	static_branch_inc(&udpv6_encap_needed_key);
 457}
 458EXPORT_SYMBOL(udpv6_encap_enable);
 459
 460/* Handler for tunnels with arbitrary destination ports: no socket lookup, go
 461 * through error handlers in encapsulations looking for a match.
 462 */
 463static int __udp6_lib_err_encap_no_sk(struct sk_buff *skb,
 464				      struct inet6_skb_parm *opt,
 465				      u8 type, u8 code, int offset, __be32 info)
 466{
 467	int i;
 468
 469	for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) {
 470		int (*handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
 471			       u8 type, u8 code, int offset, __be32 info);
 472		const struct ip6_tnl_encap_ops *encap;
 473
 474		encap = rcu_dereference(ip6tun_encaps[i]);
 475		if (!encap)
 476			continue;
 477		handler = encap->err_handler;
 478		if (handler && !handler(skb, opt, type, code, offset, info))
 479			return 0;
 480	}
 481
 482	return -ENOENT;
 483}
 484
 485/* Try to match ICMP errors to UDP tunnels by looking up a socket without
 486 * reversing source and destination port: this will match tunnels that force the
 487 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that
 488 * lwtunnels might actually break this assumption by being configured with
 489 * different destination ports on endpoints, in this case we won't be able to
 490 * trace ICMP messages back to them.
 491 *
 492 * If this doesn't match any socket, probe tunnels with arbitrary destination
 493 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port
 494 * we've sent packets to won't necessarily match the local destination port.
 495 *
 496 * Then ask the tunnel implementation to match the error against a valid
 497 * association.
 498 *
 499 * Return an error if we can't find a match, the socket if we need further
 500 * processing, zero otherwise.
 501 */
 502static struct sock *__udp6_lib_err_encap(struct net *net,
 503					 const struct ipv6hdr *hdr, int offset,
 504					 struct udphdr *uh,
 505					 struct udp_table *udptable,
 506					 struct sock *sk,
 507					 struct sk_buff *skb,
 508					 struct inet6_skb_parm *opt,
 509					 u8 type, u8 code, __be32 info)
 510{
 511	int (*lookup)(struct sock *sk, struct sk_buff *skb);
 512	int network_offset, transport_offset;
 513	struct udp_sock *up;
 514
 515	network_offset = skb_network_offset(skb);
 516	transport_offset = skb_transport_offset(skb);
 517
 518	/* Network header needs to point to the outer IPv6 header inside ICMP */
 519	skb_reset_network_header(skb);
 520
 521	/* Transport header needs to point to the UDP header */
 522	skb_set_transport_header(skb, offset);
 523
 524	if (sk) {
 525		up = udp_sk(sk);
 526
 527		lookup = READ_ONCE(up->encap_err_lookup);
 528		if (lookup && lookup(sk, skb))
 529			sk = NULL;
 530
 531		goto out;
 532	}
 533
 534	sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source,
 535			       &hdr->saddr, uh->dest,
 536			       inet6_iif(skb), 0, udptable, skb);
 537	if (sk) {
 538		up = udp_sk(sk);
 539
 540		lookup = READ_ONCE(up->encap_err_lookup);
 541		if (!lookup || lookup(sk, skb))
 542			sk = NULL;
 543	}
 544
 545out:
 546	if (!sk) {
 547		sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code,
 548							offset, info));
 549	}
 550
 551	skb_set_transport_header(skb, transport_offset);
 552	skb_set_network_header(skb, network_offset);
 553
 554	return sk;
 555}
 556
 557int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 558		   u8 type, u8 code, int offset, __be32 info,
 559		   struct udp_table *udptable)
 560{
 561	struct ipv6_pinfo *np;
 562	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 563	const struct in6_addr *saddr = &hdr->saddr;
 564	const struct in6_addr *daddr = seg6_get_daddr(skb, opt) ? : &hdr->daddr;
 565	struct udphdr *uh = (struct udphdr *)(skb->data+offset);
 566	bool tunnel = false;
 567	struct sock *sk;
 568	int harderr;
 569	int err;
 570	struct net *net = dev_net(skb->dev);
 571
 572	sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
 573			       inet6_iif(skb), inet6_sdif(skb), udptable, NULL);
 574
 575	if (!sk || READ_ONCE(udp_sk(sk)->encap_type)) {
 576		/* No socket for error: try tunnels before discarding */
 577		if (static_branch_unlikely(&udpv6_encap_needed_key)) {
 578			sk = __udp6_lib_err_encap(net, hdr, offset, uh,
 579						  udptable, sk, skb,
 580						  opt, type, code, info);
 581			if (!sk)
 582				return 0;
 583		} else
 584			sk = ERR_PTR(-ENOENT);
 585
 586		if (IS_ERR(sk)) {
 587			__ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
 588					  ICMP6_MIB_INERRORS);
 589			return PTR_ERR(sk);
 590		}
 591
 592		tunnel = true;
 593	}
 594
 595	harderr = icmpv6_err_convert(type, code, &err);
 596	np = inet6_sk(sk);
 
 
 597
 598	if (type == ICMPV6_PKT_TOOBIG) {
 599		if (!ip6_sk_accept_pmtu(sk))
 600			goto out;
 601		ip6_sk_update_pmtu(skb, sk, info);
 602		if (READ_ONCE(np->pmtudisc) != IPV6_PMTUDISC_DONT)
 603			harderr = 1;
 604	}
 605	if (type == NDISC_REDIRECT) {
 606		if (tunnel) {
 607			ip6_redirect(skb, sock_net(sk), inet6_iif(skb),
 608				     READ_ONCE(sk->sk_mark), sk->sk_uid);
 609		} else {
 610			ip6_sk_redirect(skb, sk);
 611		}
 612		goto out;
 613	}
 614
 615	/* Tunnels don't have an application socket: don't pass errors back */
 616	if (tunnel) {
 617		if (udp_sk(sk)->encap_err_rcv)
 618			udp_sk(sk)->encap_err_rcv(sk, skb, err, uh->dest,
 619						  ntohl(info), (u8 *)(uh+1));
 620		goto out;
 621	}
 622
 623	if (!inet6_test_bit(RECVERR6, sk)) {
 624		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 625			goto out;
 626	} else {
 627		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 628	}
 629
 630	sk->sk_err = err;
 631	sk_error_report(sk);
 632out:
 633	return 0;
 634}
 635
 636static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 637{
 638	int rc;
 639
 640	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 641		sock_rps_save_rxhash(sk, skb);
 642		sk_mark_napi_id(sk, skb);
 643		sk_incoming_cpu_update(sk);
 644	} else {
 645		sk_mark_napi_id_once(sk, skb);
 646	}
 647
 648	rc = __udp_enqueue_schedule_skb(sk, skb);
 649	if (rc < 0) {
 650		int is_udplite = IS_UDPLITE(sk);
 651		enum skb_drop_reason drop_reason;
 652
 653		/* Note that an ENOMEM error is charged twice */
 654		if (rc == -ENOMEM) {
 655			UDP6_INC_STATS(sock_net(sk),
 656					 UDP_MIB_RCVBUFERRORS, is_udplite);
 657			drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
 658		} else {
 659			UDP6_INC_STATS(sock_net(sk),
 660				       UDP_MIB_MEMERRORS, is_udplite);
 661			drop_reason = SKB_DROP_REASON_PROTO_MEM;
 662		}
 663		UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 664		kfree_skb_reason(skb, drop_reason);
 665		trace_udp_fail_queue_rcv_skb(rc, sk);
 666		return -1;
 667	}
 668
 669	return 0;
 670}
 671
 672static __inline__ int udpv6_err(struct sk_buff *skb,
 673				struct inet6_skb_parm *opt, u8 type,
 674				u8 code, int offset, __be32 info)
 
 
 
 
 
 
 675{
 676	return __udp6_lib_err(skb, opt, type, code, offset, info,
 677			      dev_net(skb->dev)->ipv4.udp_table);
 678}
 
 679
 680static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
 681{
 682	enum skb_drop_reason drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
 683	struct udp_sock *up = udp_sk(sk);
 
 684	int is_udplite = IS_UDPLITE(sk);
 685
 686	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
 687		drop_reason = SKB_DROP_REASON_XFRM_POLICY;
 688		goto drop;
 689	}
 690	nf_reset_ct(skb);
 691
 692	if (static_branch_unlikely(&udpv6_encap_needed_key) &&
 693	    READ_ONCE(up->encap_type)) {
 694		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
 695
 696		/*
 697		 * This is an encapsulation socket so pass the skb to
 698		 * the socket's udp_encap_rcv() hook. Otherwise, just
 699		 * fall through and pass this up the UDP socket.
 700		 * up->encap_rcv() returns the following value:
 701		 * =0 if skb was successfully passed to the encap
 702		 *    handler or was discarded by it.
 703		 * >0 if skb should be passed on to UDP.
 704		 * <0 if skb should be resubmitted as proto -N
 705		 */
 706
 707		/* if we're overly short, let UDP handle it */
 708		encap_rcv = READ_ONCE(up->encap_rcv);
 709		if (encap_rcv) {
 710			int ret;
 711
 712			/* Verify checksum before giving to encap */
 713			if (udp_lib_checksum_complete(skb))
 714				goto csum_error;
 715
 716			ret = encap_rcv(sk, skb);
 717			if (ret <= 0) {
 718				__UDP6_INC_STATS(sock_net(sk),
 719						 UDP_MIB_INDATAGRAMS,
 720						 is_udplite);
 721				return -ret;
 722			}
 723		}
 724
 725		/* FALLTHROUGH -- it's a UDP Packet */
 726	}
 727
 728	/*
 729	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 730	 */
 731	if (udp_test_bit(UDPLITE_RECV_CC, sk) && UDP_SKB_CB(skb)->partial_cov) {
 732		u16 pcrlen = READ_ONCE(up->pcrlen);
 733
 734		if (pcrlen == 0) {          /* full coverage was set  */
 735			net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
 736					    UDP_SKB_CB(skb)->cscov, skb->len);
 
 737			goto drop;
 738		}
 739		if (UDP_SKB_CB(skb)->cscov < pcrlen) {
 740			net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
 741					    UDP_SKB_CB(skb)->cscov, pcrlen);
 
 742			goto drop;
 743		}
 744	}
 745
 746	prefetch(&sk->sk_rmem_alloc);
 747	if (rcu_access_pointer(sk->sk_filter) &&
 748	    udp_lib_checksum_complete(skb))
 749		goto csum_error;
 750
 751	if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) {
 752		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
 753		goto drop;
 754	}
 755
 756	udp_csum_pull_header(skb);
 
 757
 758	skb_dst_drop(skb);
 759
 760	return __udpv6_queue_rcv_skb(sk, skb);
 
 
 
 
 
 
 
 
 761
 
 762csum_error:
 763	drop_reason = SKB_DROP_REASON_UDP_CSUM;
 764	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 765drop:
 766	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 767	atomic_inc(&sk->sk_drops);
 768	kfree_skb_reason(skb, drop_reason);
 769	return -1;
 770}
 771
 772static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 773{
 774	struct sk_buff *next, *segs;
 775	int ret;
 
 
 
 
 776
 777	if (likely(!udp_unexpected_gso(sk, skb)))
 778		return udpv6_queue_rcv_one_skb(sk, skb);
 779
 780	__skb_push(skb, -skb_mac_offset(skb));
 781	segs = udp_rcv_segment(sk, skb, false);
 782	skb_list_walk_safe(segs, skb, next) {
 783		__skb_pull(skb, skb_transport_offset(skb));
 784
 785		udp_post_segment_fix_csum(skb);
 786		ret = udpv6_queue_rcv_one_skb(sk, skb);
 787		if (ret > 0)
 788			ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret,
 789						 true);
 790	}
 791	return 0;
 792}
 
 
 
 
 793
 794static bool __udp_v6_is_mcast_sock(struct net *net, const struct sock *sk,
 795				   __be16 loc_port, const struct in6_addr *loc_addr,
 796				   __be16 rmt_port, const struct in6_addr *rmt_addr,
 797				   int dif, int sdif, unsigned short hnum)
 798{
 799	const struct inet_sock *inet = inet_sk(sk);
 800
 801	if (!net_eq(sock_net(sk), net))
 802		return false;
 803
 804	if (udp_sk(sk)->udp_port_hash != hnum ||
 805	    sk->sk_family != PF_INET6 ||
 806	    (inet->inet_dport && inet->inet_dport != rmt_port) ||
 807	    (!ipv6_addr_any(&sk->sk_v6_daddr) &&
 808		    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
 809	    !udp_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif, sdif) ||
 810	    (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 811		    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
 812		return false;
 813	if (!inet6_mc_check(sk, loc_addr, rmt_addr))
 814		return false;
 815	return true;
 816}
 817
 818static void udp6_csum_zero_error(struct sk_buff *skb)
 
 819{
 820	/* RFC 2460 section 8.1 says that we SHOULD log
 821	 * this error. Well, it is reasonable.
 822	 */
 823	net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
 824			    &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
 825			    &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
 826}
 
 
 
 
 
 
 
 
 827
 
 
 
 
 
 
 828/*
 829 * Note: called only from the BH handler context,
 830 * so we don't need to lock the hashes.
 831 */
 832static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 833		const struct in6_addr *saddr, const struct in6_addr *daddr,
 834		struct udp_table *udptable, int proto)
 835{
 836	struct sock *sk, *first = NULL;
 837	const struct udphdr *uh = udp_hdr(skb);
 838	unsigned short hnum = ntohs(uh->dest);
 839	struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
 840	unsigned int offset = offsetof(typeof(*sk), sk_node);
 841	unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
 842	int dif = inet6_iif(skb);
 843	int sdif = inet6_sdif(skb);
 844	struct hlist_node *node;
 845	struct sk_buff *nskb;
 846
 847	if (use_hash2) {
 848		hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
 849			    udptable->mask;
 850		hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
 851start_lookup:
 852		hslot = &udptable->hash2[hash2];
 853		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 854	}
 855
 856	sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
 857		if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
 858					    uh->source, saddr, dif, sdif,
 859					    hnum))
 860			continue;
 861		/* If zero checksum and no_check is not on for
 862		 * the socket then skip it.
 863		 */
 864		if (!uh->check && !udp_get_no_check6_rx(sk))
 865			continue;
 866		if (!first) {
 867			first = sk;
 868			continue;
 869		}
 870		nskb = skb_clone(skb, GFP_ATOMIC);
 871		if (unlikely(!nskb)) {
 872			atomic_inc(&sk->sk_drops);
 873			__UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
 874					 IS_UDPLITE(sk));
 875			__UDP6_INC_STATS(net, UDP_MIB_INERRORS,
 876					 IS_UDPLITE(sk));
 877			continue;
 878		}
 879
 880		if (udpv6_queue_rcv_skb(sk, nskb) > 0)
 881			consume_skb(nskb);
 882	}
 
 
 
 
 
 883
 884	/* Also lookup *:port if we are using hash2 and haven't done so yet. */
 885	if (use_hash2 && hash2 != hash2_any) {
 886		hash2 = hash2_any;
 887		goto start_lookup;
 888	}
 889
 890	if (first) {
 891		if (udpv6_queue_rcv_skb(first, skb) > 0)
 892			consume_skb(skb);
 893	} else {
 894		kfree_skb(skb);
 895		__UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
 896				 proto == IPPROTO_UDPLITE);
 897	}
 898	return 0;
 899}
 900
 901static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
 902{
 903	if (udp_sk_rx_dst_set(sk, dst)) {
 904		const struct rt6_info *rt = (const struct rt6_info *)dst;
 905
 906		sk->sk_rx_dst_cookie = rt6_get_cookie(rt);
 907	}
 908}
 909
 910/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
 911 * return code conversion for ip layer consumption
 912 */
 913static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
 914				struct udphdr *uh)
 915{
 916	int ret;
 917
 918	if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
 919		skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo);
 920
 921	ret = udpv6_queue_rcv_skb(sk, skb);
 922
 923	/* a return value > 0 means to resubmit the input */
 924	if (ret > 0)
 925		return ret;
 926	return 0;
 927}
 928
 929int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 930		   int proto)
 931{
 932	enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
 933	const struct in6_addr *saddr, *daddr;
 934	struct net *net = dev_net(skb->dev);
 935	struct udphdr *uh;
 936	struct sock *sk;
 937	bool refcounted;
 
 938	u32 ulen = 0;
 939
 940	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 941		goto discard;
 942
 943	saddr = &ipv6_hdr(skb)->saddr;
 944	daddr = &ipv6_hdr(skb)->daddr;
 945	uh = udp_hdr(skb);
 946
 947	ulen = ntohs(uh->len);
 948	if (ulen > skb->len)
 949		goto short_packet;
 950
 951	if (proto == IPPROTO_UDP) {
 952		/* UDP validates ulen. */
 953
 954		/* Check for jumbo payload */
 955		if (ulen == 0)
 956			ulen = skb->len;
 957
 958		if (ulen < sizeof(*uh))
 959			goto short_packet;
 960
 961		if (ulen < skb->len) {
 962			if (pskb_trim_rcsum(skb, ulen))
 963				goto short_packet;
 964			saddr = &ipv6_hdr(skb)->saddr;
 965			daddr = &ipv6_hdr(skb)->daddr;
 966			uh = udp_hdr(skb);
 967		}
 968	}
 969
 970	if (udp6_csum_init(skb, uh, proto))
 971		goto csum_error;
 972
 973	/* Check if the socket is already available, e.g. due to early demux */
 974	sk = inet6_steal_sock(net, skb, sizeof(struct udphdr), saddr, uh->source, daddr, uh->dest,
 975			      &refcounted, udp6_ehashfn);
 976	if (IS_ERR(sk))
 977		goto no_sk;
 978
 979	if (sk) {
 980		struct dst_entry *dst = skb_dst(skb);
 981		int ret;
 982
 983		if (unlikely(rcu_dereference(sk->sk_rx_dst) != dst))
 984			udp6_sk_rx_dst_set(sk, dst);
 985
 986		if (!uh->check && !udp_get_no_check6_rx(sk)) {
 987			if (refcounted)
 988				sock_put(sk);
 989			goto report_csum_error;
 990		}
 991
 992		ret = udp6_unicast_rcv_skb(sk, skb, uh);
 993		if (refcounted)
 994			sock_put(sk);
 995		return ret;
 996	}
 997
 998	/*
 999	 *	Multicast receive code
1000	 */
1001	if (ipv6_addr_is_multicast(daddr))
1002		return __udp6_lib_mcast_deliver(net, skb,
1003				saddr, daddr, udptable, proto);
1004
1005	/* Unicast */
 
 
 
 
 
1006	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
1007	if (sk) {
1008		if (!uh->check && !udp_get_no_check6_rx(sk))
1009			goto report_csum_error;
1010		return udp6_unicast_rcv_skb(sk, skb, uh);
1011	}
1012no_sk:
1013	reason = SKB_DROP_REASON_NO_SOCKET;
 
 
 
 
1014
1015	if (!uh->check)
1016		goto report_csum_error;
1017
1018	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1019		goto discard;
1020	nf_reset_ct(skb);
1021
1022	if (udp_lib_checksum_complete(skb))
1023		goto csum_error;
1024
1025	__UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
1026	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
1027
1028	kfree_skb_reason(skb, reason);
1029	return 0;
1030
1031short_packet:
1032	if (reason == SKB_DROP_REASON_NOT_SPECIFIED)
1033		reason = SKB_DROP_REASON_PKT_TOO_SMALL;
1034	net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
1035			    proto == IPPROTO_UDPLITE ? "-Lite" : "",
1036			    saddr, ntohs(uh->source),
1037			    ulen, skb->len,
1038			    daddr, ntohs(uh->dest));
 
1039	goto discard;
1040
1041report_csum_error:
1042	udp6_csum_zero_error(skb);
1043csum_error:
1044	if (reason == SKB_DROP_REASON_NOT_SPECIFIED)
1045		reason = SKB_DROP_REASON_UDP_CSUM;
1046	__UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
1047discard:
1048	__UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
1049	kfree_skb_reason(skb, reason);
1050	return 0;
1051}
1052
1053
1054static struct sock *__udp6_lib_demux_lookup(struct net *net,
1055			__be16 loc_port, const struct in6_addr *loc_addr,
1056			__be16 rmt_port, const struct in6_addr *rmt_addr,
1057			int dif, int sdif)
1058{
1059	struct udp_table *udptable = net->ipv4.udp_table;
1060	unsigned short hnum = ntohs(loc_port);
1061	unsigned int hash2, slot2;
1062	struct udp_hslot *hslot2;
1063	__portpair ports;
1064	struct sock *sk;
1065
1066	hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
1067	slot2 = hash2 & udptable->mask;
1068	hslot2 = &udptable->hash2[slot2];
1069	ports = INET_COMBINED_PORTS(rmt_port, hnum);
1070
1071	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
1072		if (sk->sk_state == TCP_ESTABLISHED &&
1073		    inet6_match(net, sk, rmt_addr, loc_addr, ports, dif, sdif))
1074			return sk;
1075		/* Only check first socket in chain */
1076		break;
1077	}
1078	return NULL;
1079}
1080
1081void udp_v6_early_demux(struct sk_buff *skb)
1082{
1083	struct net *net = dev_net(skb->dev);
1084	const struct udphdr *uh;
1085	struct sock *sk;
1086	struct dst_entry *dst;
1087	int dif = skb->dev->ifindex;
1088	int sdif = inet6_sdif(skb);
1089
1090	if (!pskb_may_pull(skb, skb_transport_offset(skb) +
1091	    sizeof(struct udphdr)))
1092		return;
1093
1094	uh = udp_hdr(skb);
1095
1096	if (skb->pkt_type == PACKET_HOST)
1097		sk = __udp6_lib_demux_lookup(net, uh->dest,
1098					     &ipv6_hdr(skb)->daddr,
1099					     uh->source, &ipv6_hdr(skb)->saddr,
1100					     dif, sdif);
1101	else
1102		return;
1103
1104	if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
1105		return;
1106
1107	skb->sk = sk;
1108	skb->destructor = sock_efree;
1109	dst = rcu_dereference(sk->sk_rx_dst);
1110
1111	if (dst)
1112		dst = dst_check(dst, sk->sk_rx_dst_cookie);
1113	if (dst) {
1114		/* set noref for now.
1115		 * any place which wants to hold dst has to call
1116		 * dst_hold_safe()
1117		 */
1118		skb_dst_set_noref(skb, dst);
1119	}
1120}
1121
1122INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb)
1123{
1124	return __udp6_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP);
1125}
1126
1127/*
1128 * Throw away all pending data and cancel the corking. Socket is locked.
1129 */
1130static void udp_v6_flush_pending_frames(struct sock *sk)
1131{
1132	struct udp_sock *up = udp_sk(sk);
1133
1134	if (up->pending == AF_INET)
1135		udp_flush_pending_frames(sk);
1136	else if (up->pending) {
1137		up->len = 0;
1138		WRITE_ONCE(up->pending, 0);
1139		ip6_flush_pending_frames(sk);
1140	}
1141}
1142
1143static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
1144			     int addr_len)
1145{
1146	if (addr_len < offsetofend(struct sockaddr, sa_family))
1147		return -EINVAL;
1148	/* The following checks are replicated from __ip6_datagram_connect()
1149	 * and intended to prevent BPF program called below from accessing
1150	 * bytes that are out of the bound specified by user in addr_len.
1151	 */
1152	if (uaddr->sa_family == AF_INET) {
1153		if (ipv6_only_sock(sk))
1154			return -EAFNOSUPPORT;
1155		return udp_pre_connect(sk, uaddr, addr_len);
1156	}
1157
1158	if (addr_len < SIN6_LEN_RFC2133)
1159		return -EINVAL;
1160
1161	return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr, &addr_len);
1162}
1163
1164/**
1165 *	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
1166 *	@sk:	socket we are sending on
1167 *	@skb:	sk_buff containing the filled-in UDP header
1168 *		(checksum field must be zeroed out)
1169 *	@saddr: source address
1170 *	@daddr: destination address
1171 *	@len:	length of packet
1172 */
1173static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
1174				 const struct in6_addr *saddr,
1175				 const struct in6_addr *daddr, int len)
1176{
1177	unsigned int offset;
1178	struct udphdr *uh = udp_hdr(skb);
1179	struct sk_buff *frags = skb_shinfo(skb)->frag_list;
1180	__wsum csum = 0;
1181
1182	if (!frags) {
1183		/* Only one fragment on the socket.  */
1184		skb->csum_start = skb_transport_header(skb) - skb->head;
1185		skb->csum_offset = offsetof(struct udphdr, check);
1186		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1187	} else {
1188		/*
1189		 * HW-checksum won't work as there are two or more
1190		 * fragments on the socket so that all csums of sk_buffs
1191		 * should be together
1192		 */
1193		offset = skb_transport_offset(skb);
1194		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1195		csum = skb->csum;
1196
1197		skb->ip_summed = CHECKSUM_NONE;
1198
1199		do {
1200			csum = csum_add(csum, frags->csum);
1201		} while ((frags = frags->next));
1202
1203		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1204					    csum);
1205		if (uh->check == 0)
1206			uh->check = CSUM_MANGLED_0;
1207	}
1208}
1209
1210/*
1211 *	Sending
1212 */
1213
1214static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
1215			   struct inet_cork *cork)
1216{
1217	struct sock *sk = skb->sk;
1218	struct udphdr *uh;
 
 
 
1219	int err = 0;
1220	int is_udplite = IS_UDPLITE(sk);
1221	__wsum csum = 0;
1222	int offset = skb_transport_offset(skb);
1223	int len = skb->len - offset;
1224	int datalen = len - sizeof(*uh);
 
 
 
 
 
 
1225
1226	/*
1227	 * Create a UDP header
1228	 */
1229	uh = udp_hdr(skb);
1230	uh->source = fl6->fl6_sport;
1231	uh->dest = fl6->fl6_dport;
1232	uh->len = htons(len);
1233	uh->check = 0;
1234
1235	if (cork->gso_size) {
1236		const int hlen = skb_network_header_len(skb) +
1237				 sizeof(struct udphdr);
1238
1239		if (hlen + cork->gso_size > cork->fragsize) {
1240			kfree_skb(skb);
1241			return -EINVAL;
1242		}
1243		if (datalen > cork->gso_size * UDP_MAX_SEGMENTS) {
1244			kfree_skb(skb);
1245			return -EINVAL;
1246		}
1247		if (udp_get_no_check6_tx(sk)) {
1248			kfree_skb(skb);
1249			return -EINVAL;
1250		}
1251		if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
1252		    dst_xfrm(skb_dst(skb))) {
1253			kfree_skb(skb);
1254			return -EIO;
1255		}
1256
1257		if (datalen > cork->gso_size) {
1258			skb_shinfo(skb)->gso_size = cork->gso_size;
1259			skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
1260			skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
1261								 cork->gso_size);
1262		}
1263		goto csum_partial;
1264	}
1265
1266	if (is_udplite)
1267		csum = udplite_csum(skb);
1268	else if (udp_get_no_check6_tx(sk)) {   /* UDP csum disabled */
1269		skb->ip_summed = CHECKSUM_NONE;
1270		goto send;
1271	} else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1272csum_partial:
1273		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1274		goto send;
1275	} else
1276		csum = udp_csum(skb);
1277
1278	/* add protocol-dependent pseudo-header */
1279	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1280				    len, fl6->flowi6_proto, csum);
1281	if (uh->check == 0)
1282		uh->check = CSUM_MANGLED_0;
1283
1284send:
1285	err = ip6_send_skb(skb);
1286	if (err) {
1287		if (err == -ENOBUFS && !inet6_test_bit(RECVERR6, sk)) {
1288			UDP6_INC_STATS(sock_net(sk),
1289				       UDP_MIB_SNDBUFERRORS, is_udplite);
1290			err = 0;
1291		}
1292	} else {
1293		UDP6_INC_STATS(sock_net(sk),
1294			       UDP_MIB_OUTDATAGRAMS, is_udplite);
1295	}
1296	return err;
1297}
1298
1299static int udp_v6_push_pending_frames(struct sock *sk)
1300{
1301	struct sk_buff *skb;
1302	struct udp_sock  *up = udp_sk(sk);
1303	int err = 0;
1304
1305	if (up->pending == AF_INET)
1306		return udp_push_pending_frames(sk);
1307
1308	skb = ip6_finish_skb(sk);
1309	if (!skb)
1310		goto out;
1311
1312	err = udp_v6_send_skb(skb, &inet_sk(sk)->cork.fl.u.ip6,
1313			      &inet_sk(sk)->cork.base);
1314out:
1315	up->len = 0;
1316	WRITE_ONCE(up->pending, 0);
1317	return err;
1318}
1319
1320int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
1321{
1322	struct ipv6_txoptions opt_space;
1323	struct udp_sock *up = udp_sk(sk);
1324	struct inet_sock *inet = inet_sk(sk);
1325	struct ipv6_pinfo *np = inet6_sk(sk);
1326	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1327	struct in6_addr *daddr, *final_p, final;
1328	struct ipv6_txoptions *opt = NULL;
1329	struct ipv6_txoptions *opt_to_free = NULL;
1330	struct ip6_flowlabel *flowlabel = NULL;
1331	struct inet_cork_full cork;
1332	struct flowi6 *fl6 = &cork.fl.u.ip6;
1333	struct dst_entry *dst;
1334	struct ipcm6_cookie ipc6;
1335	int addr_len = msg->msg_namelen;
1336	bool connected = false;
1337	int ulen = len;
1338	int corkreq = udp_test_bit(CORK, sk) || msg->msg_flags & MSG_MORE;
 
 
 
1339	int err;
 
1340	int is_udplite = IS_UDPLITE(sk);
1341	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1342
1343	ipcm6_init(&ipc6);
1344	ipc6.gso_size = READ_ONCE(up->gso_size);
1345	ipc6.sockc.tsflags = READ_ONCE(sk->sk_tsflags);
1346	ipc6.sockc.mark = READ_ONCE(sk->sk_mark);
1347
1348	/* destination address check */
1349	if (sin6) {
1350		if (addr_len < offsetof(struct sockaddr, sa_data))
1351			return -EINVAL;
1352
1353		switch (sin6->sin6_family) {
1354		case AF_INET6:
1355			if (addr_len < SIN6_LEN_RFC2133)
1356				return -EINVAL;
1357			daddr = &sin6->sin6_addr;
1358			if (ipv6_addr_any(daddr) &&
1359			    ipv6_addr_v4mapped(&np->saddr))
1360				ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1361						       daddr);
1362			break;
1363		case AF_INET:
1364			goto do_udp_sendmsg;
1365		case AF_UNSPEC:
1366			msg->msg_name = sin6 = NULL;
1367			msg->msg_namelen = addr_len = 0;
1368			daddr = NULL;
1369			break;
1370		default:
1371			return -EINVAL;
1372		}
1373	} else if (!READ_ONCE(up->pending)) {
1374		if (sk->sk_state != TCP_ESTABLISHED)
1375			return -EDESTADDRREQ;
1376		daddr = &sk->sk_v6_daddr;
1377	} else
1378		daddr = NULL;
1379
1380	if (daddr) {
1381		if (ipv6_addr_v4mapped(daddr)) {
1382			struct sockaddr_in sin;
1383			sin.sin_family = AF_INET;
1384			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1385			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1386			msg->msg_name = &sin;
1387			msg->msg_namelen = sizeof(sin);
1388do_udp_sendmsg:
1389			err = ipv6_only_sock(sk) ?
1390				-ENETUNREACH : udp_sendmsg(sk, msg, len);
1391			msg->msg_name = sin6;
1392			msg->msg_namelen = addr_len;
1393			return err;
1394		}
1395	}
1396
 
 
 
1397	/* Rough check on arithmetic overflow,
1398	   better check is made in ip6_append_data().
1399	   */
1400	if (len > INT_MAX - sizeof(struct udphdr))
1401		return -EMSGSIZE;
1402
1403	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1404	if (READ_ONCE(up->pending)) {
1405		if (READ_ONCE(up->pending) == AF_INET)
1406			return udp_sendmsg(sk, msg, len);
1407		/*
1408		 * There are pending frames.
1409		 * The socket lock must be held while it's corked.
1410		 */
1411		lock_sock(sk);
1412		if (likely(up->pending)) {
1413			if (unlikely(up->pending != AF_INET6)) {
1414				release_sock(sk);
1415				return -EAFNOSUPPORT;
1416			}
1417			dst = NULL;
1418			goto do_append_data;
1419		}
1420		release_sock(sk);
1421	}
1422	ulen += sizeof(struct udphdr);
1423
1424	memset(fl6, 0, sizeof(*fl6));
1425
1426	if (sin6) {
1427		if (sin6->sin6_port == 0)
1428			return -EINVAL;
1429
1430		fl6->fl6_dport = sin6->sin6_port;
1431		daddr = &sin6->sin6_addr;
1432
1433		if (inet6_test_bit(SNDFLOW, sk)) {
1434			fl6->flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1435			if (fl6->flowlabel & IPV6_FLOWLABEL_MASK) {
1436				flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
1437				if (IS_ERR(flowlabel))
1438					return -EINVAL;
1439			}
1440		}
1441
1442		/*
1443		 * Otherwise it will be difficult to maintain
1444		 * sk->sk_dst_cache.
1445		 */
1446		if (sk->sk_state == TCP_ESTABLISHED &&
1447		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1448			daddr = &sk->sk_v6_daddr;
1449
1450		if (addr_len >= sizeof(struct sockaddr_in6) &&
1451		    sin6->sin6_scope_id &&
1452		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1453			fl6->flowi6_oif = sin6->sin6_scope_id;
1454	} else {
1455		if (sk->sk_state != TCP_ESTABLISHED)
1456			return -EDESTADDRREQ;
1457
1458		fl6->fl6_dport = inet->inet_dport;
1459		daddr = &sk->sk_v6_daddr;
1460		fl6->flowlabel = np->flow_label;
1461		connected = true;
1462	}
1463
1464	if (!fl6->flowi6_oif)
1465		fl6->flowi6_oif = READ_ONCE(sk->sk_bound_dev_if);
1466
1467	if (!fl6->flowi6_oif)
1468		fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1469
1470	fl6->flowi6_uid = sk->sk_uid;
1471
1472	if (msg->msg_controllen) {
1473		opt = &opt_space;
1474		memset(opt, 0, sizeof(struct ipv6_txoptions));
1475		opt->tot_len = sizeof(*opt);
1476		ipc6.opt = opt;
1477
1478		err = udp_cmsg_send(sk, msg, &ipc6.gso_size);
1479		if (err > 0)
1480			err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, fl6,
1481						    &ipc6);
1482		if (err < 0) {
1483			fl6_sock_release(flowlabel);
1484			return err;
1485		}
1486		if ((fl6->flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1487			flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
1488			if (IS_ERR(flowlabel))
1489				return -EINVAL;
1490		}
1491		if (!(opt->opt_nflen|opt->opt_flen))
1492			opt = NULL;
1493		connected = false;
1494	}
1495	if (!opt) {
1496		opt = txopt_get(np);
1497		opt_to_free = opt;
1498	}
 
 
1499	if (flowlabel)
1500		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1501	opt = ipv6_fixup_options(&opt_space, opt);
1502	ipc6.opt = opt;
1503
1504	fl6->flowi6_proto = sk->sk_protocol;
1505	fl6->flowi6_mark = ipc6.sockc.mark;
1506	fl6->daddr = *daddr;
1507	if (ipv6_addr_any(&fl6->saddr) && !ipv6_addr_any(&np->saddr))
1508		fl6->saddr = np->saddr;
1509	fl6->fl6_sport = inet->inet_sport;
1510
1511	if (cgroup_bpf_enabled(CGROUP_UDP6_SENDMSG) && !connected) {
1512		err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk,
1513					   (struct sockaddr *)sin6,
1514					   &addr_len,
1515					   &fl6->saddr);
1516		if (err)
1517			goto out_no_dst;
1518		if (sin6) {
1519			if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
1520				/* BPF program rewrote IPv6-only by IPv4-mapped
1521				 * IPv6. It's currently unsupported.
1522				 */
1523				err = -ENOTSUPP;
1524				goto out_no_dst;
1525			}
1526			if (sin6->sin6_port == 0) {
1527				/* BPF program set invalid port. Reject it. */
1528				err = -EINVAL;
1529				goto out_no_dst;
1530			}
1531			fl6->fl6_dport = sin6->sin6_port;
1532			fl6->daddr = sin6->sin6_addr;
1533		}
1534	}
1535
1536	if (ipv6_addr_any(&fl6->daddr))
1537		fl6->daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
 
 
 
 
 
 
1538
1539	final_p = fl6_update_dst(fl6, opt, &final);
1540	if (final_p)
1541		connected = false;
1542
1543	if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) {
1544		fl6->flowi6_oif = READ_ONCE(np->mcast_oif);
1545		connected = false;
1546	} else if (!fl6->flowi6_oif)
1547		fl6->flowi6_oif = READ_ONCE(np->ucast_oif);
1548
1549	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
1550
1551	if (ipc6.tclass < 0)
1552		ipc6.tclass = np->tclass;
 
 
 
1553
1554	fl6->flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6->flowlabel);
1555
1556	dst = ip6_sk_dst_lookup_flow(sk, fl6, final_p, connected);
1557	if (IS_ERR(dst)) {
1558		err = PTR_ERR(dst);
1559		dst = NULL;
1560		goto out;
1561	}
1562
1563	if (ipc6.hlimit < 0)
1564		ipc6.hlimit = ip6_sk_dst_hoplimit(np, fl6, dst);
 
 
 
 
 
 
 
 
 
1565
1566	if (msg->msg_flags&MSG_CONFIRM)
1567		goto do_confirm;
1568back_from_confirm:
1569
1570	/* Lockless fast path for the non-corking case */
1571	if (!corkreq) {
1572		struct sk_buff *skb;
1573
1574		skb = ip6_make_skb(sk, getfrag, msg, ulen,
1575				   sizeof(struct udphdr), &ipc6,
1576				   (struct rt6_info *)dst,
1577				   msg->msg_flags, &cork);
1578		err = PTR_ERR(skb);
1579		if (!IS_ERR_OR_NULL(skb))
1580			err = udp_v6_send_skb(skb, fl6, &cork.base);
1581		/* ip6_make_skb steals dst reference */
1582		goto out_no_dst;
1583	}
1584
1585	lock_sock(sk);
1586	if (unlikely(up->pending)) {
1587		/* The socket is already corked while preparing it. */
1588		/* ... which is an evident application bug. --ANK */
1589		release_sock(sk);
1590
1591		net_dbg_ratelimited("udp cork app bug 2\n");
1592		err = -EINVAL;
1593		goto out;
1594	}
1595
1596	WRITE_ONCE(up->pending, AF_INET6);
1597
1598do_append_data:
1599	if (ipc6.dontfrag < 0)
1600		ipc6.dontfrag = inet6_test_bit(DONTFRAG, sk);
1601	up->len += ulen;
1602	err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1603			      &ipc6, fl6, (struct rt6_info *)dst,
1604			      corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
 
 
1605	if (err)
1606		udp_v6_flush_pending_frames(sk);
1607	else if (!corkreq)
1608		err = udp_v6_push_pending_frames(sk);
1609	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1610		WRITE_ONCE(up->pending, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1611
1612	if (err > 0)
1613		err = inet6_test_bit(RECVERR6, sk) ? net_xmit_errno(err) : 0;
1614	release_sock(sk);
1615
1616out:
1617	dst_release(dst);
1618out_no_dst:
1619	fl6_sock_release(flowlabel);
1620	txopt_put(opt_to_free);
1621	if (!err)
1622		return len;
1623	/*
1624	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1625	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1626	 * we don't have a good statistic (IpOutDiscards but it can be too many
1627	 * things).  We could add another new stat but at least for now that
1628	 * seems like overkill.
1629	 */
1630	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1631		UDP6_INC_STATS(sock_net(sk),
1632			       UDP_MIB_SNDBUFERRORS, is_udplite);
1633	}
1634	return err;
1635
1636do_confirm:
1637	if (msg->msg_flags & MSG_PROBE)
1638		dst_confirm_neigh(dst, &fl6->daddr);
1639	if (!(msg->msg_flags&MSG_PROBE) || len)
1640		goto back_from_confirm;
1641	err = 0;
1642	goto out;
1643}
1644EXPORT_SYMBOL(udpv6_sendmsg);
1645
1646static void udpv6_splice_eof(struct socket *sock)
1647{
1648	struct sock *sk = sock->sk;
1649	struct udp_sock *up = udp_sk(sk);
1650
1651	if (!READ_ONCE(up->pending) || udp_test_bit(CORK, sk))
1652		return;
1653
1654	lock_sock(sk);
1655	if (up->pending && !udp_test_bit(CORK, sk))
1656		udp_v6_push_pending_frames(sk);
1657	release_sock(sk);
1658}
1659
1660void udpv6_destroy_sock(struct sock *sk)
1661{
1662	struct udp_sock *up = udp_sk(sk);
1663	lock_sock(sk);
1664
1665	/* protects from races with udp_abort() */
1666	sock_set_flag(sk, SOCK_DEAD);
1667	udp_v6_flush_pending_frames(sk);
1668	release_sock(sk);
1669
1670	if (static_branch_unlikely(&udpv6_encap_needed_key)) {
1671		if (up->encap_type) {
1672			void (*encap_destroy)(struct sock *sk);
1673			encap_destroy = READ_ONCE(up->encap_destroy);
1674			if (encap_destroy)
1675				encap_destroy(sk);
1676		}
1677		if (udp_test_bit(ENCAP_ENABLED, sk)) {
1678			static_branch_dec(&udpv6_encap_needed_key);
1679			udp_encap_disable();
1680		}
1681	}
 
 
1682}
1683
1684/*
1685 *	Socket option code for UDP
1686 */
1687int udpv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1688		     unsigned int optlen)
1689{
1690	if (level == SOL_UDP  ||  level == SOL_UDPLITE || level == SOL_SOCKET)
1691		return udp_lib_setsockopt(sk, level, optname,
1692					  optval, optlen,
1693					  udp_v6_push_pending_frames);
1694	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1695}
1696
 
 
 
 
 
 
 
 
 
 
 
1697int udpv6_getsockopt(struct sock *sk, int level, int optname,
1698		     char __user *optval, int __user *optlen)
1699{
1700	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1701		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1702	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1703}
1704
 
 
 
 
 
 
 
 
 
 
1705static const struct inet6_protocol udpv6_protocol = {
1706	.handler	=	udpv6_rcv,
1707	.err_handler	=	udpv6_err,
1708	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1709};
1710
1711/* ------------------------------------------------------------------------ */
1712#ifdef CONFIG_PROC_FS
1713int udp6_seq_show(struct seq_file *seq, void *v)
1714{
1715	if (v == SEQ_START_TOKEN) {
1716		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1717	} else {
1718		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1719		const struct inet_sock *inet = inet_sk((const struct sock *)v);
1720		__u16 srcp = ntohs(inet->inet_sport);
1721		__u16 destp = ntohs(inet->inet_dport);
1722		__ip6_dgram_sock_seq_show(seq, v, srcp, destp,
1723					  udp_rqueue_get(v), bucket);
1724	}
1725	return 0;
1726}
1727
1728const struct seq_operations udp6_seq_ops = {
1729	.start		= udp_seq_start,
1730	.next		= udp_seq_next,
1731	.stop		= udp_seq_stop,
1732	.show		= udp6_seq_show,
 
1733};
1734EXPORT_SYMBOL(udp6_seq_ops);
1735
1736static struct udp_seq_afinfo udp6_seq_afinfo = {
 
1737	.family		= AF_INET6,
1738	.udp_table	= NULL,
 
 
 
 
1739};
1740
1741int __net_init udp6_proc_init(struct net *net)
1742{
1743	if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops,
1744			sizeof(struct udp_iter_state), &udp6_seq_afinfo))
1745		return -ENOMEM;
1746	return 0;
1747}
1748
1749void udp6_proc_exit(struct net *net)
1750{
1751	remove_proc_entry("udp6", net->proc_net);
1752}
1753#endif /* CONFIG_PROC_FS */
1754
 
 
 
 
 
 
 
 
 
 
 
1755/* ------------------------------------------------------------------------ */
1756
1757struct proto udpv6_prot = {
1758	.name			= "UDPv6",
1759	.owner			= THIS_MODULE,
1760	.close			= udp_lib_close,
1761	.pre_connect		= udpv6_pre_connect,
1762	.connect		= ip6_datagram_connect,
1763	.disconnect		= udp_disconnect,
1764	.ioctl			= udp_ioctl,
1765	.init			= udpv6_init_sock,
1766	.destroy		= udpv6_destroy_sock,
1767	.setsockopt		= udpv6_setsockopt,
1768	.getsockopt		= udpv6_getsockopt,
1769	.sendmsg		= udpv6_sendmsg,
1770	.recvmsg		= udpv6_recvmsg,
1771	.splice_eof		= udpv6_splice_eof,
1772	.release_cb		= ip6_datagram_release_cb,
1773	.hash			= udp_lib_hash,
1774	.unhash			= udp_lib_unhash,
1775	.rehash			= udp_v6_rehash,
1776	.get_port		= udp_v6_get_port,
1777	.put_port		= udp_lib_unhash,
1778#ifdef CONFIG_BPF_SYSCALL
1779	.psock_update_sk_prot	= udp_bpf_update_proto,
 
 
 
 
1780#endif
1781
1782	.memory_allocated	= &udp_memory_allocated,
1783	.per_cpu_fw_alloc	= &udp_memory_per_cpu_fw_alloc,
1784
1785	.sysctl_mem		= sysctl_udp_mem,
1786	.sysctl_wmem_offset     = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1787	.sysctl_rmem_offset     = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1788	.obj_size		= sizeof(struct udp6_sock),
1789	.ipv6_pinfo_offset = offsetof(struct udp6_sock, inet6),
1790	.h.udp_table		= NULL,
1791	.diag_destroy		= udp_abort,
1792};
1793
1794static struct inet_protosw udpv6_protosw = {
1795	.type =      SOCK_DGRAM,
1796	.protocol =  IPPROTO_UDP,
1797	.prot =      &udpv6_prot,
1798	.ops =       &inet6_dgram_ops,
 
1799	.flags =     INET_PROTOSW_PERMANENT,
1800};
 
1801
1802int __init udpv6_init(void)
1803{
1804	int ret;
1805
1806	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1807	if (ret)
1808		goto out;
1809
1810	ret = inet6_register_protosw(&udpv6_protosw);
1811	if (ret)
1812		goto out_udpv6_protocol;
1813out:
1814	return ret;
1815
1816out_udpv6_protocol:
1817	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1818	goto out;
1819}
1820
1821void udpv6_exit(void)
1822{
1823	inet6_unregister_protosw(&udpv6_protosw);
1824	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1825}
v3.15
 
   1/*
   2 *	UDP over IPv6
   3 *	Linux INET6 implementation
   4 *
   5 *	Authors:
   6 *	Pedro Roque		<roque@di.fc.ul.pt>
   7 *
   8 *	Based on linux/ipv4/udp.c
   9 *
  10 *	Fixes:
  11 *	Hideaki YOSHIFUJI	:	sin6_scope_id support
  12 *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
  13 *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
  14 *					a single port at the same time.
  15 *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
  16 *      YOSHIFUJI Hideaki @USAGI:	convert /proc/net/udp6 to seq_file.
  17 *
  18 *	This program is free software; you can redistribute it and/or
  19 *      modify it under the terms of the GNU General Public License
  20 *      as published by the Free Software Foundation; either version
  21 *      2 of the License, or (at your option) any later version.
  22 */
  23
 
  24#include <linux/errno.h>
  25#include <linux/types.h>
  26#include <linux/socket.h>
  27#include <linux/sockios.h>
  28#include <linux/net.h>
  29#include <linux/in6.h>
  30#include <linux/netdevice.h>
  31#include <linux/if_arp.h>
  32#include <linux/ipv6.h>
  33#include <linux/icmpv6.h>
  34#include <linux/init.h>
  35#include <linux/module.h>
  36#include <linux/skbuff.h>
  37#include <linux/slab.h>
  38#include <asm/uaccess.h>
 
  39
 
  40#include <net/ndisc.h>
  41#include <net/protocol.h>
  42#include <net/transp_v6.h>
  43#include <net/ip6_route.h>
  44#include <net/raw.h>
 
  45#include <net/tcp_states.h>
  46#include <net/ip6_checksum.h>
 
 
  47#include <net/xfrm.h>
 
  48#include <net/inet6_hashtables.h>
  49#include <net/busy_poll.h>
 
 
  50
  51#include <linux/proc_fs.h>
  52#include <linux/seq_file.h>
  53#include <trace/events/skb.h>
  54#include "udp_impl.h"
  55
  56static unsigned int udp6_ehashfn(struct net *net,
  57				  const struct in6_addr *laddr,
  58				  const u16 lport,
  59				  const struct in6_addr *faddr,
  60				  const __be16 fport)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  61{
  62	static u32 udp6_ehash_secret __read_mostly;
  63	static u32 udp_ipv6_hash_secret __read_mostly;
  64
  65	u32 lhash, fhash;
  66
  67	net_get_random_once(&udp6_ehash_secret,
  68			    sizeof(udp6_ehash_secret));
  69	net_get_random_once(&udp_ipv6_hash_secret,
  70			    sizeof(udp_ipv6_hash_secret));
  71
  72	lhash = (__force u32)laddr->s6_addr32[3];
  73	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
  74
  75	return __inet6_ehashfn(lhash, lport, fhash, fport,
  76			       udp_ipv6_hash_secret + net_hash_mix(net));
  77}
  78
  79int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
  80{
  81	const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
  82	int sk_ipv6only = ipv6_only_sock(sk);
  83	int sk2_ipv6only = inet_v6_ipv6only(sk2);
  84	int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
  85	int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
  86
  87	/* if both are mapped, treat as IPv4 */
  88	if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED)
  89		return (!sk2_ipv6only &&
  90			(!sk->sk_rcv_saddr || !sk2->sk_rcv_saddr ||
  91			  sk->sk_rcv_saddr == sk2->sk_rcv_saddr));
  92
  93	if (addr_type2 == IPV6_ADDR_ANY &&
  94	    !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
  95		return 1;
  96
  97	if (addr_type == IPV6_ADDR_ANY &&
  98	    !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED))
  99		return 1;
 100
 101	if (sk2_rcv_saddr6 &&
 102	    ipv6_addr_equal(&sk->sk_v6_rcv_saddr, sk2_rcv_saddr6))
 103		return 1;
 104
 105	return 0;
 106}
 107
 108static unsigned int udp6_portaddr_hash(struct net *net,
 109				       const struct in6_addr *addr6,
 110				       unsigned int port)
 111{
 112	unsigned int hash, mix = net_hash_mix(net);
 113
 114	if (ipv6_addr_any(addr6))
 115		hash = jhash_1word(0, mix);
 116	else if (ipv6_addr_v4mapped(addr6))
 117		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
 118	else
 119		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
 120
 121	return hash ^ port;
 122}
 123
 124
 125int udp_v6_get_port(struct sock *sk, unsigned short snum)
 126{
 127	unsigned int hash2_nulladdr =
 128		udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
 129	unsigned int hash2_partial =
 130		udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
 131
 132	/* precompute partial secondary hash */
 133	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
 134	return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
 135}
 136
 137static void udp_v6_rehash(struct sock *sk)
 138{
 139	u16 new_hash = udp6_portaddr_hash(sock_net(sk),
 140					  &sk->sk_v6_rcv_saddr,
 141					  inet_sk(sk)->inet_num);
 142
 143	udp_lib_rehash(sk, new_hash);
 144}
 145
 146static inline int compute_score(struct sock *sk, struct net *net,
 147				unsigned short hnum,
 148				const struct in6_addr *saddr, __be16 sport,
 149				const struct in6_addr *daddr, __be16 dport,
 150				int dif)
 151{
 152	int score = -1;
 153
 154	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
 155			sk->sk_family == PF_INET6) {
 156		struct inet_sock *inet = inet_sk(sk);
 157
 158		score = 0;
 159		if (inet->inet_dport) {
 160			if (inet->inet_dport != sport)
 161				return -1;
 162			score++;
 163		}
 164		if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
 165			if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 166				return -1;
 167			score++;
 168		}
 169		if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 170			if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 171				return -1;
 172			score++;
 173		}
 174		if (sk->sk_bound_dev_if) {
 175			if (sk->sk_bound_dev_if != dif)
 176				return -1;
 177			score++;
 178		}
 179	}
 180	return score;
 181}
 182
 183#define SCORE2_MAX (1 + 1 + 1)
 184static inline int compute_score2(struct sock *sk, struct net *net,
 185				const struct in6_addr *saddr, __be16 sport,
 186				const struct in6_addr *daddr, unsigned short hnum,
 187				int dif)
 188{
 189	int score = -1;
 190
 191	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
 192			sk->sk_family == PF_INET6) {
 193		struct inet_sock *inet = inet_sk(sk);
 194
 195		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 196			return -1;
 197		score = 0;
 198		if (inet->inet_dport) {
 199			if (inet->inet_dport != sport)
 200				return -1;
 201			score++;
 202		}
 203		if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 204			if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 205				return -1;
 206			score++;
 207		}
 208		if (sk->sk_bound_dev_if) {
 209			if (sk->sk_bound_dev_if != dif)
 210				return -1;
 211			score++;
 212		}
 213	}
 
 
 
 
 
 
 
 
 
 
 
 214	return score;
 215}
 216
 217
 218/* called with read_rcu_lock() */
 219static struct sock *udp6_lib_lookup2(struct net *net,
 220		const struct in6_addr *saddr, __be16 sport,
 221		const struct in6_addr *daddr, unsigned int hnum, int dif,
 222		struct udp_hslot *hslot2, unsigned int slot2)
 
 223{
 224	struct sock *sk, *result;
 225	struct hlist_nulls_node *node;
 226	int score, badness, matches = 0, reuseport = 0;
 227	u32 hash = 0;
 228
 229begin:
 230	result = NULL;
 231	badness = -1;
 232	udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
 233		score = compute_score2(sk, net, saddr, sport,
 234				      daddr, hnum, dif);
 235		if (score > badness) {
 236			result = sk;
 237			badness = score;
 238			reuseport = sk->sk_reuseport;
 239			if (reuseport) {
 240				hash = udp6_ehashfn(net, daddr, hnum,
 241						    saddr, sport);
 242				matches = 1;
 243			} else if (score == SCORE2_MAX)
 244				goto exact_match;
 245		} else if (score == badness && reuseport) {
 246			matches++;
 247			if (((u64)hash * matches) >> 32 == 0)
 248				result = sk;
 249			hash = next_pseudo_random32(hash);
 250		}
 251	}
 252	/*
 253	 * if the nulls value we got at the end of this lookup is
 254	 * not the expected one, we must restart lookup.
 255	 * We probably met an item that was moved to another chain.
 256	 */
 257	if (get_nulls_value(node) != slot2)
 258		goto begin;
 259
 260	if (result) {
 261exact_match:
 262		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 263			result = NULL;
 264		else if (unlikely(compute_score2(result, net, saddr, sport,
 265				  daddr, hnum, dif) < badness)) {
 266			sock_put(result);
 267			goto begin;
 268		}
 269	}
 270	return result;
 271}
 272
 
 273struct sock *__udp6_lib_lookup(struct net *net,
 274				      const struct in6_addr *saddr, __be16 sport,
 275				      const struct in6_addr *daddr, __be16 dport,
 276				      int dif, struct udp_table *udptable)
 
 277{
 278	struct sock *sk, *result;
 279	struct hlist_nulls_node *node;
 280	unsigned short hnum = ntohs(dport);
 281	unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
 282	struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
 283	int score, badness, matches = 0, reuseport = 0;
 284	u32 hash = 0;
 285
 286	rcu_read_lock();
 287	if (hslot->count > 10) {
 288		hash2 = udp6_portaddr_hash(net, daddr, hnum);
 289		slot2 = hash2 & udptable->mask;
 290		hslot2 = &udptable->hash2[slot2];
 291		if (hslot->count < hslot2->count)
 292			goto begin;
 293
 294		result = udp6_lib_lookup2(net, saddr, sport,
 295					  daddr, hnum, dif,
 296					  hslot2, slot2);
 297		if (!result) {
 298			hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
 299			slot2 = hash2 & udptable->mask;
 300			hslot2 = &udptable->hash2[slot2];
 301			if (hslot->count < hslot2->count)
 302				goto begin;
 303
 304			result = udp6_lib_lookup2(net, saddr, sport,
 305						  &in6addr_any, hnum, dif,
 306						  hslot2, slot2);
 307		}
 308		rcu_read_unlock();
 309		return result;
 310	}
 311begin:
 312	result = NULL;
 313	badness = -1;
 314	sk_nulls_for_each_rcu(sk, node, &hslot->head) {
 315		score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
 316		if (score > badness) {
 317			result = sk;
 318			badness = score;
 319			reuseport = sk->sk_reuseport;
 320			if (reuseport) {
 321				hash = udp6_ehashfn(net, daddr, hnum,
 322						    saddr, sport);
 323				matches = 1;
 324			}
 325		} else if (score == badness && reuseport) {
 326			matches++;
 327			if (((u64)hash * matches) >> 32 == 0)
 328				result = sk;
 329			hash = next_pseudo_random32(hash);
 330		}
 331	}
 332	/*
 333	 * if the nulls value we got at the end of this lookup is
 334	 * not the expected one, we must restart lookup.
 335	 * We probably met an item that was moved to another chain.
 336	 */
 337	if (get_nulls_value(node) != slot)
 338		goto begin;
 339
 340	if (result) {
 341		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 342			result = NULL;
 343		else if (unlikely(compute_score(result, net, hnum, saddr, sport,
 344					daddr, dport, dif) < badness)) {
 345			sock_put(result);
 346			goto begin;
 347		}
 348	}
 349	rcu_read_unlock();
 
 
 
 
 
 350	return result;
 351}
 352EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
 353
 354static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 355					  __be16 sport, __be16 dport,
 356					  struct udp_table *udptable)
 357{
 358	struct sock *sk;
 359	const struct ipv6hdr *iph = ipv6_hdr(skb);
 360
 361	if (unlikely(sk = skb_steal_sock(skb)))
 362		return sk;
 363	return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
 364				 &iph->daddr, dport, inet6_iif(skb),
 365				 udptable);
 366}
 367
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 368struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 369			     const struct in6_addr *daddr, __be16 dport, int dif)
 370{
 371	return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
 
 
 
 
 
 
 372}
 373EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 
 374
 
 
 
 
 
 
 
 
 375
 376/*
 377 * 	This should be easy, if there is something there we
 378 * 	return it, otherwise we block.
 379 */
 380
 381int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 382		  struct msghdr *msg, size_t len,
 383		  int noblock, int flags, int *addr_len)
 384{
 385	struct ipv6_pinfo *np = inet6_sk(sk);
 386	struct inet_sock *inet = inet_sk(sk);
 387	struct sk_buff *skb;
 388	unsigned int ulen, copied;
 389	int peeked, off = 0;
 390	int err;
 391	int is_udplite = IS_UDPLITE(sk);
 
 
 392	int is_udp4;
 393	bool slow;
 394
 395	if (flags & MSG_ERRQUEUE)
 396		return ipv6_recv_error(sk, msg, len, addr_len);
 397
 398	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 399		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 400
 401try_again:
 402	skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
 403				  &peeked, &off, &err);
 404	if (!skb)
 405		goto out;
 406
 407	ulen = skb->len - sizeof(struct udphdr);
 408	copied = len;
 409	if (copied > ulen)
 410		copied = ulen;
 411	else if (copied < ulen)
 412		msg->msg_flags |= MSG_TRUNC;
 413
 414	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 
 415
 416	/*
 417	 * If checksum is needed at all, try to do it while copying the
 418	 * data.  If the data is truncated, or if we only want a partial
 419	 * coverage checksum (UDP-Lite), do it before the copy.
 420	 */
 421
 422	if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
 423		if (udp_lib_checksum_complete(skb))
 
 
 
 424			goto csum_copy_err;
 425	}
 426
 427	if (skb_csum_unnecessary(skb))
 428		err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
 429					      msg->msg_iov, copied);
 430	else {
 431		err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 
 
 432		if (err == -EINVAL)
 433			goto csum_copy_err;
 434	}
 435	if (unlikely(err)) {
 436		trace_kfree_skb(skb, udpv6_recvmsg);
 437		if (!peeked) {
 438			atomic_inc(&sk->sk_drops);
 439			if (is_udp4)
 440				UDP_INC_STATS_USER(sock_net(sk),
 441						   UDP_MIB_INERRORS,
 442						   is_udplite);
 443			else
 444				UDP6_INC_STATS_USER(sock_net(sk),
 445						    UDP_MIB_INERRORS,
 446						    is_udplite);
 447		}
 448		goto out_free;
 449	}
 450	if (!peeked) {
 451		if (is_udp4)
 452			UDP_INC_STATS_USER(sock_net(sk),
 453					UDP_MIB_INDATAGRAMS, is_udplite);
 454		else
 455			UDP6_INC_STATS_USER(sock_net(sk),
 456					UDP_MIB_INDATAGRAMS, is_udplite);
 457	}
 
 
 458
 459	sock_recv_ts_and_drops(msg, sk, skb);
 460
 461	/* Copy the address. */
 462	if (msg->msg_name) {
 463		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 464		sin6->sin6_family = AF_INET6;
 465		sin6->sin6_port = udp_hdr(skb)->source;
 466		sin6->sin6_flowinfo = 0;
 467
 468		if (is_udp4) {
 469			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 470					       &sin6->sin6_addr);
 471			sin6->sin6_scope_id = 0;
 472		} else {
 473			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 474			sin6->sin6_scope_id =
 475				ipv6_iface_scope_id(&sin6->sin6_addr,
 476						    IP6CB(skb)->iif);
 477		}
 478		*addr_len = sizeof(*sin6);
 
 
 
 
 479	}
 480
 
 
 
 481	if (np->rxopt.all)
 482		ip6_datagram_recv_common_ctl(sk, msg, skb);
 483
 484	if (is_udp4) {
 485		if (inet->cmsg_flags)
 486			ip_cmsg_recv(msg, skb);
 
 487	} else {
 488		if (np->rxopt.all)
 489			ip6_datagram_recv_specific_ctl(sk, msg, skb);
 490	}
 491
 492	err = copied;
 493	if (flags & MSG_TRUNC)
 494		err = ulen;
 495
 496out_free:
 497	skb_free_datagram_locked(sk, skb);
 498out:
 499	return err;
 500
 501csum_copy_err:
 502	slow = lock_sock_fast(sk);
 503	if (!skb_kill_datagram(sk, skb, flags)) {
 504		if (is_udp4) {
 505			UDP_INC_STATS_USER(sock_net(sk),
 506					UDP_MIB_CSUMERRORS, is_udplite);
 507			UDP_INC_STATS_USER(sock_net(sk),
 508					UDP_MIB_INERRORS, is_udplite);
 509		} else {
 510			UDP6_INC_STATS_USER(sock_net(sk),
 511					UDP_MIB_CSUMERRORS, is_udplite);
 512			UDP6_INC_STATS_USER(sock_net(sk),
 513					UDP_MIB_INERRORS, is_udplite);
 514		}
 515	}
 516	unlock_sock_fast(sk, slow);
 517
 518	if (noblock)
 519		return -EAGAIN;
 520
 521	/* starting over for a new packet */
 
 522	msg->msg_flags &= ~MSG_TRUNC;
 523	goto try_again;
 524}
 525
 526void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 527		    u8 type, u8 code, int offset, __be32 info,
 528		    struct udp_table *udptable)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 529{
 530	struct ipv6_pinfo *np;
 531	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 532	const struct in6_addr *saddr = &hdr->saddr;
 533	const struct in6_addr *daddr = &hdr->daddr;
 534	struct udphdr *uh = (struct udphdr*)(skb->data+offset);
 
 535	struct sock *sk;
 
 536	int err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 537
 538	sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
 539			       saddr, uh->source, inet6_iif(skb), udptable);
 540	if (sk == NULL)
 541		return;
 542
 543	if (type == ICMPV6_PKT_TOOBIG) {
 544		if (!ip6_sk_accept_pmtu(sk))
 545			goto out;
 546		ip6_sk_update_pmtu(skb, sk, info);
 
 
 547	}
 548	if (type == NDISC_REDIRECT) {
 549		ip6_sk_redirect(skb, sk);
 
 
 
 
 
 550		goto out;
 551	}
 552
 553	np = inet6_sk(sk);
 554
 555	if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
 
 
 556		goto out;
 
 557
 558	if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
 559		goto out;
 560
 561	if (np->recverr)
 562		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 
 563
 564	sk->sk_err = err;
 565	sk->sk_error_report(sk);
 566out:
 567	sock_put(sk);
 568}
 569
 570static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 571{
 572	int rc;
 573
 574	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 575		sock_rps_save_rxhash(sk, skb);
 576		sk_mark_napi_id(sk, skb);
 
 
 
 577	}
 578
 579	rc = sock_queue_rcv_skb(sk, skb);
 580	if (rc < 0) {
 581		int is_udplite = IS_UDPLITE(sk);
 
 582
 583		/* Note that an ENOMEM error is charged twice */
 584		if (rc == -ENOMEM)
 585			UDP6_INC_STATS_BH(sock_net(sk),
 586					UDP_MIB_RCVBUFERRORS, is_udplite);
 587		UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 588		kfree_skb(skb);
 
 
 
 
 
 
 
 589		return -1;
 590	}
 
 591	return 0;
 592}
 593
 594static __inline__ void udpv6_err(struct sk_buff *skb,
 595				 struct inet6_skb_parm *opt, u8 type,
 596				 u8 code, int offset, __be32 info     )
 597{
 598	__udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 599}
 600
 601static struct static_key udpv6_encap_needed __read_mostly;
 602void udpv6_encap_enable(void)
 603{
 604	if (!static_key_enabled(&udpv6_encap_needed))
 605		static_key_slow_inc(&udpv6_encap_needed);
 606}
 607EXPORT_SYMBOL(udpv6_encap_enable);
 608
 609int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 610{
 
 611	struct udp_sock *up = udp_sk(sk);
 612	int rc;
 613	int is_udplite = IS_UDPLITE(sk);
 614
 615	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 
 616		goto drop;
 
 
 617
 618	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
 
 619		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
 620
 621		/*
 622		 * This is an encapsulation socket so pass the skb to
 623		 * the socket's udp_encap_rcv() hook. Otherwise, just
 624		 * fall through and pass this up the UDP socket.
 625		 * up->encap_rcv() returns the following value:
 626		 * =0 if skb was successfully passed to the encap
 627		 *    handler or was discarded by it.
 628		 * >0 if skb should be passed on to UDP.
 629		 * <0 if skb should be resubmitted as proto -N
 630		 */
 631
 632		/* if we're overly short, let UDP handle it */
 633		encap_rcv = ACCESS_ONCE(up->encap_rcv);
 634		if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) {
 635			int ret;
 636
 
 
 
 
 637			ret = encap_rcv(sk, skb);
 638			if (ret <= 0) {
 639				UDP_INC_STATS_BH(sock_net(sk),
 640						 UDP_MIB_INDATAGRAMS,
 641						 is_udplite);
 642				return -ret;
 643			}
 644		}
 645
 646		/* FALLTHROUGH -- it's a UDP Packet */
 647	}
 648
 649	/*
 650	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 651	 */
 652	if ((is_udplite & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 
 653
 654		if (up->pcrlen == 0) {          /* full coverage was set  */
 655			LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
 656				" %d while full coverage %d requested\n",
 657				UDP_SKB_CB(skb)->cscov, skb->len);
 658			goto drop;
 659		}
 660		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 661			LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
 662						    "too small, need min %d\n",
 663				       UDP_SKB_CB(skb)->cscov, up->pcrlen);
 664			goto drop;
 665		}
 666	}
 667
 668	if (rcu_access_pointer(sk->sk_filter)) {
 669		if (udp_lib_checksum_complete(skb))
 670			goto csum_error;
 
 
 
 
 
 671	}
 672
 673	if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
 674		goto drop;
 675
 676	skb_dst_drop(skb);
 677
 678	bh_lock_sock(sk);
 679	rc = 0;
 680	if (!sock_owned_by_user(sk))
 681		rc = __udpv6_queue_rcv_skb(sk, skb);
 682	else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
 683		bh_unlock_sock(sk);
 684		goto drop;
 685	}
 686	bh_unlock_sock(sk);
 687
 688	return rc;
 689csum_error:
 690	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 
 691drop:
 692	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 693	atomic_inc(&sk->sk_drops);
 694	kfree_skb(skb);
 695	return -1;
 696}
 697
 698static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
 699				      __be16 loc_port, const struct in6_addr *loc_addr,
 700				      __be16 rmt_port, const struct in6_addr *rmt_addr,
 701				      int dif)
 702{
 703	struct hlist_nulls_node *node;
 704	struct sock *s = sk;
 705	unsigned short num = ntohs(loc_port);
 706
 707	sk_nulls_for_each_from(s, node) {
 708		struct inet_sock *inet = inet_sk(s);
 709
 710		if (!net_eq(sock_net(s), net))
 711			continue;
 
 
 712
 713		if (udp_sk(s)->udp_port_hash == num &&
 714		    s->sk_family == PF_INET6) {
 715			if (inet->inet_dport) {
 716				if (inet->inet_dport != rmt_port)
 717					continue;
 718			}
 719			if (!ipv6_addr_any(&sk->sk_v6_daddr) &&
 720			    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr))
 721				continue;
 722
 723			if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 724				continue;
 725
 726			if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
 727				if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))
 728					continue;
 729			}
 730			if (!inet6_mc_check(s, loc_addr, rmt_addr))
 731				continue;
 732			return s;
 733		}
 734	}
 735	return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 736}
 737
 738static void flush_stack(struct sock **stack, unsigned int count,
 739			struct sk_buff *skb, unsigned int final)
 740{
 741	struct sk_buff *skb1 = NULL;
 742	struct sock *sk;
 743	unsigned int i;
 744
 745	for (i = 0; i < count; i++) {
 746		sk = stack[i];
 747		if (likely(skb1 == NULL))
 748			skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
 749		if (!skb1) {
 750			atomic_inc(&sk->sk_drops);
 751			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
 752					  IS_UDPLITE(sk));
 753			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
 754					  IS_UDPLITE(sk));
 755		}
 756
 757		if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
 758			skb1 = NULL;
 759	}
 760	if (unlikely(skb1))
 761		kfree_skb(skb1);
 762}
 763/*
 764 * Note: called only from the BH handler context,
 765 * so we don't need to lock the hashes.
 766 */
 767static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 768		const struct in6_addr *saddr, const struct in6_addr *daddr,
 769		struct udp_table *udptable)
 770{
 771	struct sock *sk, *stack[256 / sizeof(struct sock *)];
 772	const struct udphdr *uh = udp_hdr(skb);
 773	struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
 774	int dif;
 775	unsigned int i, count = 0;
 776
 777	spin_lock(&hslot->lock);
 778	sk = sk_nulls_head(&hslot->head);
 779	dif = inet6_iif(skb);
 780	sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
 781	while (sk) {
 782		stack[count++] = sk;
 783		sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
 784				       uh->source, saddr, dif);
 785		if (unlikely(count == ARRAY_SIZE(stack))) {
 786			if (!sk)
 787				break;
 788			flush_stack(stack, count, skb, ~0);
 789			count = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 790		}
 
 
 
 791	}
 792	/*
 793	 * before releasing the lock, we must take reference on sockets
 794	 */
 795	for (i = 0; i < count; i++)
 796		sock_hold(stack[i]);
 797
 798	spin_unlock(&hslot->lock);
 799
 800	if (count) {
 801		flush_stack(stack, count, skb, count - 1);
 
 802
 803		for (i = 0; i < count; i++)
 804			sock_put(stack[i]);
 
 805	} else {
 806		kfree_skb(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 807	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 808	return 0;
 809}
 810
 811int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 812		   int proto)
 813{
 
 
 814	struct net *net = dev_net(skb->dev);
 
 815	struct sock *sk;
 816	struct udphdr *uh;
 817	const struct in6_addr *saddr, *daddr;
 818	u32 ulen = 0;
 819
 820	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 821		goto discard;
 822
 823	saddr = &ipv6_hdr(skb)->saddr;
 824	daddr = &ipv6_hdr(skb)->daddr;
 825	uh = udp_hdr(skb);
 826
 827	ulen = ntohs(uh->len);
 828	if (ulen > skb->len)
 829		goto short_packet;
 830
 831	if (proto == IPPROTO_UDP) {
 832		/* UDP validates ulen. */
 833
 834		/* Check for jumbo payload */
 835		if (ulen == 0)
 836			ulen = skb->len;
 837
 838		if (ulen < sizeof(*uh))
 839			goto short_packet;
 840
 841		if (ulen < skb->len) {
 842			if (pskb_trim_rcsum(skb, ulen))
 843				goto short_packet;
 844			saddr = &ipv6_hdr(skb)->saddr;
 845			daddr = &ipv6_hdr(skb)->daddr;
 846			uh = udp_hdr(skb);
 847		}
 848	}
 849
 850	if (udp6_csum_init(skb, uh, proto))
 851		goto csum_error;
 852
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 853	/*
 854	 *	Multicast receive code
 855	 */
 856	if (ipv6_addr_is_multicast(daddr))
 857		return __udp6_lib_mcast_deliver(net, skb,
 858				saddr, daddr, udptable);
 859
 860	/* Unicast */
 861
 862	/*
 863	 * check socket cache ... must talk to Alan about his plans
 864	 * for sock caches... i'll skip this for now.
 865	 */
 866	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
 867	if (sk != NULL) {
 868		int ret;
 869
 870		ret = udpv6_queue_rcv_skb(sk, skb);
 871		sock_put(sk);
 872
 873		/* a return value > 0 means to resubmit the input, but
 874		 * it wants the return to be -protocol, or 0
 875		 */
 876		if (ret > 0)
 877			return -ret;
 878
 879		return 0;
 880	}
 881
 882	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 883		goto discard;
 
 884
 885	if (udp_lib_checksum_complete(skb))
 886		goto csum_error;
 887
 888	UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
 889	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 890
 891	kfree_skb(skb);
 892	return 0;
 893
 894short_packet:
 895	LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
 896		       proto == IPPROTO_UDPLITE ? "-Lite" : "",
 897		       saddr,
 898		       ntohs(uh->source),
 899		       ulen,
 900		       skb->len,
 901		       daddr,
 902		       ntohs(uh->dest));
 903	goto discard;
 
 
 
 904csum_error:
 905	UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
 
 
 906discard:
 907	UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
 908	kfree_skb(skb);
 909	return 0;
 910}
 911
 912static __inline__ int udpv6_rcv(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 913{
 914	return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 915}
 916
 917/*
 918 * Throw away all pending data and cancel the corking. Socket is locked.
 919 */
 920static void udp_v6_flush_pending_frames(struct sock *sk)
 921{
 922	struct udp_sock *up = udp_sk(sk);
 923
 924	if (up->pending == AF_INET)
 925		udp_flush_pending_frames(sk);
 926	else if (up->pending) {
 927		up->len = 0;
 928		up->pending = 0;
 929		ip6_flush_pending_frames(sk);
 930	}
 931}
 932
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 933/**
 934 * 	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
 935 * 	@sk: 	socket we are sending on
 936 * 	@skb: 	sk_buff containing the filled-in UDP header
 937 * 	        (checksum field must be zeroed out)
 
 
 
 938 */
 939static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
 940				 const struct in6_addr *saddr,
 941				 const struct in6_addr *daddr, int len)
 942{
 943	unsigned int offset;
 944	struct udphdr *uh = udp_hdr(skb);
 
 945	__wsum csum = 0;
 946
 947	if (skb_queue_len(&sk->sk_write_queue) == 1) {
 948		/* Only one fragment on the socket.  */
 949		skb->csum_start = skb_transport_header(skb) - skb->head;
 950		skb->csum_offset = offsetof(struct udphdr, check);
 951		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
 952	} else {
 953		/*
 954		 * HW-checksum won't work as there are two or more
 955		 * fragments on the socket so that all csums of sk_buffs
 956		 * should be together
 957		 */
 958		offset = skb_transport_offset(skb);
 959		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
 
 960
 961		skb->ip_summed = CHECKSUM_NONE;
 962
 963		skb_queue_walk(&sk->sk_write_queue, skb) {
 964			csum = csum_add(csum, skb->csum);
 965		}
 966
 967		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
 968					    csum);
 969		if (uh->check == 0)
 970			uh->check = CSUM_MANGLED_0;
 971	}
 972}
 973
 974/*
 975 *	Sending
 976 */
 977
 978static int udp_v6_push_pending_frames(struct sock *sk)
 
 979{
 980	struct sk_buff *skb;
 981	struct udphdr *uh;
 982	struct udp_sock  *up = udp_sk(sk);
 983	struct inet_sock *inet = inet_sk(sk);
 984	struct flowi6 *fl6;
 985	int err = 0;
 986	int is_udplite = IS_UDPLITE(sk);
 987	__wsum csum = 0;
 988
 989	if (up->pending == AF_INET)
 990		return udp_push_pending_frames(sk);
 991
 992	fl6 = &inet->cork.fl.u.ip6;
 993
 994	/* Grab the skbuff where UDP header space exists. */
 995	if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 996		goto out;
 997
 998	/*
 999	 * Create a UDP header
1000	 */
1001	uh = udp_hdr(skb);
1002	uh->source = fl6->fl6_sport;
1003	uh->dest = fl6->fl6_dport;
1004	uh->len = htons(up->len);
1005	uh->check = 0;
1006
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1007	if (is_udplite)
1008		csum = udplite_csum_outgoing(sk, skb);
1009	else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1010		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
1011				     up->len);
 
 
 
1012		goto send;
1013	} else
1014		csum = udp_csum_outgoing(sk, skb);
1015
1016	/* add protocol-dependent pseudo-header */
1017	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1018				    up->len, fl6->flowi6_proto, csum);
1019	if (uh->check == 0)
1020		uh->check = CSUM_MANGLED_0;
1021
1022send:
1023	err = ip6_push_pending_frames(sk);
1024	if (err) {
1025		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1026			UDP6_INC_STATS_USER(sock_net(sk),
1027					    UDP_MIB_SNDBUFERRORS, is_udplite);
1028			err = 0;
1029		}
1030	} else
1031		UDP6_INC_STATS_USER(sock_net(sk),
1032				    UDP_MIB_OUTDATAGRAMS, is_udplite);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1033out:
1034	up->len = 0;
1035	up->pending = 0;
1036	return err;
1037}
1038
1039int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
1040		  struct msghdr *msg, size_t len)
1041{
1042	struct ipv6_txoptions opt_space;
1043	struct udp_sock *up = udp_sk(sk);
1044	struct inet_sock *inet = inet_sk(sk);
1045	struct ipv6_pinfo *np = inet6_sk(sk);
1046	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1047	struct in6_addr *daddr, *final_p, final;
1048	struct ipv6_txoptions *opt = NULL;
 
1049	struct ip6_flowlabel *flowlabel = NULL;
1050	struct flowi6 fl6;
 
1051	struct dst_entry *dst;
 
1052	int addr_len = msg->msg_namelen;
 
1053	int ulen = len;
1054	int hlimit = -1;
1055	int tclass = -1;
1056	int dontfrag = -1;
1057	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1058	int err;
1059	int connected = 0;
1060	int is_udplite = IS_UDPLITE(sk);
1061	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1062
 
 
 
 
 
1063	/* destination address check */
1064	if (sin6) {
1065		if (addr_len < offsetof(struct sockaddr, sa_data))
1066			return -EINVAL;
1067
1068		switch (sin6->sin6_family) {
1069		case AF_INET6:
1070			if (addr_len < SIN6_LEN_RFC2133)
1071				return -EINVAL;
1072			daddr = &sin6->sin6_addr;
 
 
 
 
1073			break;
1074		case AF_INET:
1075			goto do_udp_sendmsg;
1076		case AF_UNSPEC:
1077			msg->msg_name = sin6 = NULL;
1078			msg->msg_namelen = addr_len = 0;
1079			daddr = NULL;
1080			break;
1081		default:
1082			return -EINVAL;
1083		}
1084	} else if (!up->pending) {
1085		if (sk->sk_state != TCP_ESTABLISHED)
1086			return -EDESTADDRREQ;
1087		daddr = &sk->sk_v6_daddr;
1088	} else
1089		daddr = NULL;
1090
1091	if (daddr) {
1092		if (ipv6_addr_v4mapped(daddr)) {
1093			struct sockaddr_in sin;
1094			sin.sin_family = AF_INET;
1095			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1096			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1097			msg->msg_name = &sin;
1098			msg->msg_namelen = sizeof(sin);
1099do_udp_sendmsg:
1100			if (__ipv6_only_sock(sk))
1101				return -ENETUNREACH;
1102			return udp_sendmsg(iocb, sk, msg, len);
 
 
1103		}
1104	}
1105
1106	if (up->pending == AF_INET)
1107		return udp_sendmsg(iocb, sk, msg, len);
1108
1109	/* Rough check on arithmetic overflow,
1110	   better check is made in ip6_append_data().
1111	   */
1112	if (len > INT_MAX - sizeof(struct udphdr))
1113		return -EMSGSIZE;
1114
1115	if (up->pending) {
 
 
 
1116		/*
1117		 * There are pending frames.
1118		 * The socket lock must be held while it's corked.
1119		 */
1120		lock_sock(sk);
1121		if (likely(up->pending)) {
1122			if (unlikely(up->pending != AF_INET6)) {
1123				release_sock(sk);
1124				return -EAFNOSUPPORT;
1125			}
1126			dst = NULL;
1127			goto do_append_data;
1128		}
1129		release_sock(sk);
1130	}
1131	ulen += sizeof(struct udphdr);
1132
1133	memset(&fl6, 0, sizeof(fl6));
1134
1135	if (sin6) {
1136		if (sin6->sin6_port == 0)
1137			return -EINVAL;
1138
1139		fl6.fl6_dport = sin6->sin6_port;
1140		daddr = &sin6->sin6_addr;
1141
1142		if (np->sndflow) {
1143			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1144			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1145				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1146				if (flowlabel == NULL)
1147					return -EINVAL;
1148			}
1149		}
1150
1151		/*
1152		 * Otherwise it will be difficult to maintain
1153		 * sk->sk_dst_cache.
1154		 */
1155		if (sk->sk_state == TCP_ESTABLISHED &&
1156		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1157			daddr = &sk->sk_v6_daddr;
1158
1159		if (addr_len >= sizeof(struct sockaddr_in6) &&
1160		    sin6->sin6_scope_id &&
1161		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1162			fl6.flowi6_oif = sin6->sin6_scope_id;
1163	} else {
1164		if (sk->sk_state != TCP_ESTABLISHED)
1165			return -EDESTADDRREQ;
1166
1167		fl6.fl6_dport = inet->inet_dport;
1168		daddr = &sk->sk_v6_daddr;
1169		fl6.flowlabel = np->flow_label;
1170		connected = 1;
1171	}
1172
1173	if (!fl6.flowi6_oif)
1174		fl6.flowi6_oif = sk->sk_bound_dev_if;
1175
1176	if (!fl6.flowi6_oif)
1177		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1178
1179	fl6.flowi6_mark = sk->sk_mark;
1180
1181	if (msg->msg_controllen) {
1182		opt = &opt_space;
1183		memset(opt, 0, sizeof(struct ipv6_txoptions));
1184		opt->tot_len = sizeof(*opt);
 
1185
1186		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1187					    &hlimit, &tclass, &dontfrag);
 
 
1188		if (err < 0) {
1189			fl6_sock_release(flowlabel);
1190			return err;
1191		}
1192		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1193			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1194			if (flowlabel == NULL)
1195				return -EINVAL;
1196		}
1197		if (!(opt->opt_nflen|opt->opt_flen))
1198			opt = NULL;
1199		connected = 0;
 
 
 
 
1200	}
1201	if (opt == NULL)
1202		opt = np->opt;
1203	if (flowlabel)
1204		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1205	opt = ipv6_fixup_options(&opt_space, opt);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1206
1207	fl6.flowi6_proto = sk->sk_protocol;
1208	if (!ipv6_addr_any(daddr))
1209		fl6.daddr = *daddr;
1210	else
1211		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1212	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1213		fl6.saddr = np->saddr;
1214	fl6.fl6_sport = inet->inet_sport;
1215
1216	final_p = fl6_update_dst(&fl6, opt, &final);
1217	if (final_p)
1218		connected = 0;
 
 
 
 
 
 
 
 
1219
1220	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1221		fl6.flowi6_oif = np->mcast_oif;
1222		connected = 0;
1223	} else if (!fl6.flowi6_oif)
1224		fl6.flowi6_oif = np->ucast_oif;
1225
1226	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1227
1228	dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
1229	if (IS_ERR(dst)) {
1230		err = PTR_ERR(dst);
1231		dst = NULL;
1232		goto out;
1233	}
1234
1235	if (hlimit < 0) {
1236		if (ipv6_addr_is_multicast(&fl6.daddr))
1237			hlimit = np->mcast_hops;
1238		else
1239			hlimit = np->hop_limit;
1240		if (hlimit < 0)
1241			hlimit = ip6_dst_hoplimit(dst);
1242	}
1243
1244	if (tclass < 0)
1245		tclass = np->tclass;
1246
1247	if (msg->msg_flags&MSG_CONFIRM)
1248		goto do_confirm;
1249back_from_confirm:
1250
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1251	lock_sock(sk);
1252	if (unlikely(up->pending)) {
1253		/* The socket is already corked while preparing it. */
1254		/* ... which is an evident application bug. --ANK */
1255		release_sock(sk);
1256
1257		LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1258		err = -EINVAL;
1259		goto out;
1260	}
1261
1262	up->pending = AF_INET6;
1263
1264do_append_data:
1265	if (dontfrag < 0)
1266		dontfrag = np->dontfrag;
1267	up->len += ulen;
1268	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1269	err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1270		sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1271		(struct rt6_info*)dst,
1272		corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1273	if (err)
1274		udp_v6_flush_pending_frames(sk);
1275	else if (!corkreq)
1276		err = udp_v6_push_pending_frames(sk);
1277	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1278		up->pending = 0;
1279
1280	if (dst) {
1281		if (connected) {
1282			ip6_dst_store(sk, dst,
1283				      ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
1284				      &sk->sk_v6_daddr : NULL,
1285#ifdef CONFIG_IPV6_SUBTREES
1286				      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1287				      &np->saddr :
1288#endif
1289				      NULL);
1290		} else {
1291			dst_release(dst);
1292		}
1293		dst = NULL;
1294	}
1295
1296	if (err > 0)
1297		err = np->recverr ? net_xmit_errno(err) : 0;
1298	release_sock(sk);
 
1299out:
1300	dst_release(dst);
 
1301	fl6_sock_release(flowlabel);
 
1302	if (!err)
1303		return len;
1304	/*
1305	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1306	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1307	 * we don't have a good statistic (IpOutDiscards but it can be too many
1308	 * things).  We could add another new stat but at least for now that
1309	 * seems like overkill.
1310	 */
1311	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1312		UDP6_INC_STATS_USER(sock_net(sk),
1313				UDP_MIB_SNDBUFERRORS, is_udplite);
1314	}
1315	return err;
1316
1317do_confirm:
1318	dst_confirm(dst);
 
1319	if (!(msg->msg_flags&MSG_PROBE) || len)
1320		goto back_from_confirm;
1321	err = 0;
1322	goto out;
1323}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1324
1325void udpv6_destroy_sock(struct sock *sk)
1326{
1327	struct udp_sock *up = udp_sk(sk);
1328	lock_sock(sk);
 
 
 
1329	udp_v6_flush_pending_frames(sk);
1330	release_sock(sk);
1331
1332	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1333		void (*encap_destroy)(struct sock *sk);
1334		encap_destroy = ACCESS_ONCE(up->encap_destroy);
1335		if (encap_destroy)
1336			encap_destroy(sk);
 
 
 
 
 
 
1337	}
1338
1339	inet6_destroy_sock(sk);
1340}
1341
1342/*
1343 *	Socket option code for UDP
1344 */
1345int udpv6_setsockopt(struct sock *sk, int level, int optname,
1346		     char __user *optval, unsigned int optlen)
1347{
1348	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1349		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
 
1350					  udp_v6_push_pending_frames);
1351	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1352}
1353
1354#ifdef CONFIG_COMPAT
1355int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1356			    char __user *optval, unsigned int optlen)
1357{
1358	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1359		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1360					  udp_v6_push_pending_frames);
1361	return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1362}
1363#endif
1364
1365int udpv6_getsockopt(struct sock *sk, int level, int optname,
1366		     char __user *optval, int __user *optlen)
1367{
1368	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1369		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1370	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1371}
1372
1373#ifdef CONFIG_COMPAT
1374int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1375			    char __user *optval, int __user *optlen)
1376{
1377	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1378		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1379	return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1380}
1381#endif
1382
1383static const struct inet6_protocol udpv6_protocol = {
1384	.handler	=	udpv6_rcv,
1385	.err_handler	=	udpv6_err,
1386	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1387};
1388
1389/* ------------------------------------------------------------------------ */
1390#ifdef CONFIG_PROC_FS
1391int udp6_seq_show(struct seq_file *seq, void *v)
1392{
1393	if (v == SEQ_START_TOKEN) {
1394		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1395	} else {
1396		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1397		struct inet_sock *inet = inet_sk(v);
1398		__u16 srcp = ntohs(inet->inet_sport);
1399		__u16 destp = ntohs(inet->inet_dport);
1400		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
 
1401	}
1402	return 0;
1403}
1404
1405static const struct file_operations udp6_afinfo_seq_fops = {
1406	.owner    = THIS_MODULE,
1407	.open     = udp_seq_open,
1408	.read     = seq_read,
1409	.llseek   = seq_lseek,
1410	.release  = seq_release_net
1411};
 
1412
1413static struct udp_seq_afinfo udp6_seq_afinfo = {
1414	.name		= "udp6",
1415	.family		= AF_INET6,
1416	.udp_table	= &udp_table,
1417	.seq_fops	= &udp6_afinfo_seq_fops,
1418	.seq_ops	= {
1419		.show		= udp6_seq_show,
1420	},
1421};
1422
1423int __net_init udp6_proc_init(struct net *net)
1424{
1425	return udp_proc_register(net, &udp6_seq_afinfo);
 
 
 
1426}
1427
1428void udp6_proc_exit(struct net *net) {
1429	udp_proc_unregister(net, &udp6_seq_afinfo);
 
1430}
1431#endif /* CONFIG_PROC_FS */
1432
1433void udp_v6_clear_sk(struct sock *sk, int size)
1434{
1435	struct inet_sock *inet = inet_sk(sk);
1436
1437	/* we do not want to clear pinet6 field, because of RCU lookups */
1438	sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6));
1439
1440	size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
1441	memset(&inet->pinet6 + 1, 0, size);
1442}
1443
1444/* ------------------------------------------------------------------------ */
1445
1446struct proto udpv6_prot = {
1447	.name		   = "UDPv6",
1448	.owner		   = THIS_MODULE,
1449	.close		   = udp_lib_close,
1450	.connect	   = ip6_datagram_connect,
1451	.disconnect	   = udp_disconnect,
1452	.ioctl		   = udp_ioctl,
1453	.destroy	   = udpv6_destroy_sock,
1454	.setsockopt	   = udpv6_setsockopt,
1455	.getsockopt	   = udpv6_getsockopt,
1456	.sendmsg	   = udpv6_sendmsg,
1457	.recvmsg	   = udpv6_recvmsg,
1458	.backlog_rcv	   = __udpv6_queue_rcv_skb,
1459	.hash		   = udp_lib_hash,
1460	.unhash		   = udp_lib_unhash,
1461	.rehash		   = udp_v6_rehash,
1462	.get_port	   = udp_v6_get_port,
1463	.memory_allocated  = &udp_memory_allocated,
1464	.sysctl_mem	   = sysctl_udp_mem,
1465	.sysctl_wmem	   = &sysctl_udp_wmem_min,
1466	.sysctl_rmem	   = &sysctl_udp_rmem_min,
1467	.obj_size	   = sizeof(struct udp6_sock),
1468	.slab_flags	   = SLAB_DESTROY_BY_RCU,
1469	.h.udp_table	   = &udp_table,
1470#ifdef CONFIG_COMPAT
1471	.compat_setsockopt = compat_udpv6_setsockopt,
1472	.compat_getsockopt = compat_udpv6_getsockopt,
1473#endif
1474	.clear_sk	   = udp_v6_clear_sk,
 
 
 
 
 
 
 
 
 
 
1475};
1476
1477static struct inet_protosw udpv6_protosw = {
1478	.type =      SOCK_DGRAM,
1479	.protocol =  IPPROTO_UDP,
1480	.prot =      &udpv6_prot,
1481	.ops =       &inet6_dgram_ops,
1482	.no_check =  UDP_CSUM_DEFAULT,
1483	.flags =     INET_PROTOSW_PERMANENT,
1484};
1485
1486
1487int __init udpv6_init(void)
1488{
1489	int ret;
1490
1491	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1492	if (ret)
1493		goto out;
1494
1495	ret = inet6_register_protosw(&udpv6_protosw);
1496	if (ret)
1497		goto out_udpv6_protocol;
1498out:
1499	return ret;
1500
1501out_udpv6_protocol:
1502	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1503	goto out;
1504}
1505
1506void udpv6_exit(void)
1507{
1508	inet6_unregister_protosw(&udpv6_protosw);
1509	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1510}