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v4.6
 
   1/*
   2 *	UDP over IPv6
   3 *	Linux INET6 implementation
   4 *
   5 *	Authors:
   6 *	Pedro Roque		<roque@di.fc.ul.pt>
   7 *
   8 *	Based on linux/ipv4/udp.c
   9 *
  10 *	Fixes:
  11 *	Hideaki YOSHIFUJI	:	sin6_scope_id support
  12 *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
  13 *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
  14 *					a single port at the same time.
  15 *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
  16 *      YOSHIFUJI Hideaki @USAGI:	convert /proc/net/udp6 to seq_file.
  17 *
  18 *	This program is free software; you can redistribute it and/or
  19 *      modify it under the terms of the GNU General Public License
  20 *      as published by the Free Software Foundation; either version
  21 *      2 of the License, or (at your option) any later version.
  22 */
  23
  24#include <linux/errno.h>
  25#include <linux/types.h>
  26#include <linux/socket.h>
  27#include <linux/sockios.h>
  28#include <linux/net.h>
  29#include <linux/in6.h>
  30#include <linux/netdevice.h>
  31#include <linux/if_arp.h>
  32#include <linux/ipv6.h>
  33#include <linux/icmpv6.h>
  34#include <linux/init.h>
  35#include <linux/module.h>
  36#include <linux/skbuff.h>
  37#include <linux/slab.h>
  38#include <asm/uaccess.h>
 
  39
  40#include <net/addrconf.h>
  41#include <net/ndisc.h>
  42#include <net/protocol.h>
  43#include <net/transp_v6.h>
  44#include <net/ip6_route.h>
  45#include <net/raw.h>
  46#include <net/tcp_states.h>
  47#include <net/ip6_checksum.h>
 
  48#include <net/xfrm.h>
 
  49#include <net/inet6_hashtables.h>
  50#include <net/busy_poll.h>
  51#include <net/sock_reuseport.h>
  52
  53#include <linux/proc_fs.h>
  54#include <linux/seq_file.h>
  55#include <trace/events/skb.h>
  56#include "udp_impl.h"
  57
  58static u32 udp6_ehashfn(const struct net *net,
  59			const struct in6_addr *laddr,
  60			const u16 lport,
  61			const struct in6_addr *faddr,
  62			const __be16 fport)
  63{
  64	static u32 udp6_ehash_secret __read_mostly;
  65	static u32 udp_ipv6_hash_secret __read_mostly;
  66
  67	u32 lhash, fhash;
  68
  69	net_get_random_once(&udp6_ehash_secret,
  70			    sizeof(udp6_ehash_secret));
  71	net_get_random_once(&udp_ipv6_hash_secret,
  72			    sizeof(udp_ipv6_hash_secret));
  73
  74	lhash = (__force u32)laddr->s6_addr32[3];
  75	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
  76
  77	return __inet6_ehashfn(lhash, lport, fhash, fport,
  78			       udp_ipv6_hash_secret + net_hash_mix(net));
  79}
  80
  81static u32 udp6_portaddr_hash(const struct net *net,
  82			      const struct in6_addr *addr6,
  83			      unsigned int port)
  84{
  85	unsigned int hash, mix = net_hash_mix(net);
  86
  87	if (ipv6_addr_any(addr6))
  88		hash = jhash_1word(0, mix);
  89	else if (ipv6_addr_v4mapped(addr6))
  90		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
  91	else
  92		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
  93
  94	return hash ^ port;
  95}
  96
  97int udp_v6_get_port(struct sock *sk, unsigned short snum)
  98{
  99	unsigned int hash2_nulladdr =
 100		udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
 101	unsigned int hash2_partial =
 102		udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
 103
 104	/* precompute partial secondary hash */
 105	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
 106	return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
 107}
 108
 109static void udp_v6_rehash(struct sock *sk)
 110{
 111	u16 new_hash = udp6_portaddr_hash(sock_net(sk),
 112					  &sk->sk_v6_rcv_saddr,
 113					  inet_sk(sk)->inet_num);
 114
 115	udp_lib_rehash(sk, new_hash);
 116}
 117
 118static inline int compute_score(struct sock *sk, struct net *net,
 119				unsigned short hnum,
 120				const struct in6_addr *saddr, __be16 sport,
 121				const struct in6_addr *daddr, __be16 dport,
 122				int dif)
 123{
 124	int score;
 125	struct inet_sock *inet;
 
 126
 127	if (!net_eq(sock_net(sk), net) ||
 128	    udp_sk(sk)->udp_port_hash != hnum ||
 129	    sk->sk_family != PF_INET6)
 130		return -1;
 131
 
 
 
 132	score = 0;
 133	inet = inet_sk(sk);
 134
 135	if (inet->inet_dport) {
 136		if (inet->inet_dport != sport)
 137			return -1;
 138		score++;
 139	}
 140
 141	if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
 142		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 143			return -1;
 144		score++;
 145	}
 146
 147	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 148		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 149			return -1;
 150		score++;
 151	}
 152
 153	if (sk->sk_bound_dev_if) {
 154		if (sk->sk_bound_dev_if != dif)
 155			return -1;
 
 156		score++;
 157	}
 158
 159	if (sk->sk_incoming_cpu == raw_smp_processor_id())
 160		score++;
 161
 162	return score;
 163}
 164
 165static inline int compute_score2(struct sock *sk, struct net *net,
 166				 const struct in6_addr *saddr, __be16 sport,
 167				 const struct in6_addr *daddr,
 168				 unsigned short hnum, int dif)
 
 
 169{
 170	int score;
 171	struct inet_sock *inet;
 172
 173	if (!net_eq(sock_net(sk), net) ||
 174	    udp_sk(sk)->udp_port_hash != hnum ||
 175	    sk->sk_family != PF_INET6)
 176		return -1;
 177
 178	if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 179		return -1;
 180
 181	score = 0;
 182	inet = inet_sk(sk);
 183
 184	if (inet->inet_dport) {
 185		if (inet->inet_dport != sport)
 186			return -1;
 187		score++;
 188	}
 189
 190	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 191		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 192			return -1;
 193		score++;
 194	}
 195
 196	if (sk->sk_bound_dev_if) {
 197		if (sk->sk_bound_dev_if != dif)
 198			return -1;
 199		score++;
 200	}
 201
 202	if (sk->sk_incoming_cpu == raw_smp_processor_id())
 203		score++;
 204
 205	return score;
 206}
 207
 208/* called with read_rcu_lock() */
 209static struct sock *udp6_lib_lookup2(struct net *net,
 210		const struct in6_addr *saddr, __be16 sport,
 211		const struct in6_addr *daddr, unsigned int hnum, int dif,
 212		struct udp_hslot *hslot2, unsigned int slot2,
 213		struct sk_buff *skb)
 214{
 215	struct sock *sk, *result;
 216	struct hlist_nulls_node *node;
 217	int score, badness, matches = 0, reuseport = 0;
 218	bool select_ok = true;
 219	u32 hash = 0;
 220
 221begin:
 222	result = NULL;
 223	badness = -1;
 224	udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
 225		score = compute_score2(sk, net, saddr, sport,
 226				      daddr, hnum, dif);
 227		if (score > badness) {
 228			result = sk;
 229			badness = score;
 230			reuseport = sk->sk_reuseport;
 231			if (reuseport) {
 232				hash = udp6_ehashfn(net, daddr, hnum,
 233						    saddr, sport);
 234				if (select_ok) {
 235					struct sock *sk2;
 236
 237					sk2 = reuseport_select_sock(sk, hash, skb,
 238							sizeof(struct udphdr));
 239					if (sk2) {
 240						result = sk2;
 241						select_ok = false;
 242						goto found;
 243					}
 244				}
 245				matches = 1;
 246			}
 247		} else if (score == badness && reuseport) {
 248			matches++;
 249			if (reciprocal_scale(hash, matches) == 0)
 250				result = sk;
 251			hash = next_pseudo_random32(hash);
 252		}
 253	}
 254	/*
 255	 * if the nulls value we got at the end of this lookup is
 256	 * not the expected one, we must restart lookup.
 257	 * We probably met an item that was moved to another chain.
 258	 */
 259	if (get_nulls_value(node) != slot2)
 260		goto begin;
 261
 262	if (result) {
 263found:
 264		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 265			result = NULL;
 266		else if (unlikely(compute_score2(result, net, saddr, sport,
 267				  daddr, hnum, dif) < badness)) {
 268			sock_put(result);
 269			goto begin;
 270		}
 271	}
 272	return result;
 273}
 274
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 275struct sock *__udp6_lib_lookup(struct net *net,
 276				      const struct in6_addr *saddr, __be16 sport,
 277				      const struct in6_addr *daddr, __be16 dport,
 278				      int dif, struct udp_table *udptable,
 279				      struct sk_buff *skb)
 280{
 281	struct sock *sk, *result;
 282	struct hlist_nulls_node *node;
 283	unsigned short hnum = ntohs(dport);
 284	unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
 285	struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
 286	int score, badness, matches = 0, reuseport = 0;
 287	bool select_ok = true;
 288	u32 hash = 0;
 289
 290	rcu_read_lock();
 291	if (hslot->count > 10) {
 292		hash2 = udp6_portaddr_hash(net, daddr, hnum);
 293		slot2 = hash2 & udptable->mask;
 294		hslot2 = &udptable->hash2[slot2];
 295		if (hslot->count < hslot2->count)
 296			goto begin;
 297
 298		result = udp6_lib_lookup2(net, saddr, sport,
 299					  daddr, hnum, dif,
 300					  hslot2, slot2, skb);
 301		if (!result) {
 302			hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
 303			slot2 = hash2 & udptable->mask;
 304			hslot2 = &udptable->hash2[slot2];
 305			if (hslot->count < hslot2->count)
 306				goto begin;
 307
 308			result = udp6_lib_lookup2(net, saddr, sport,
 309						  &in6addr_any, hnum, dif,
 310						  hslot2, slot2, skb);
 311		}
 312		rcu_read_unlock();
 313		return result;
 314	}
 315begin:
 316	result = NULL;
 317	badness = -1;
 318	sk_nulls_for_each_rcu(sk, node, &hslot->head) {
 319		score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
 320		if (score > badness) {
 321			result = sk;
 322			badness = score;
 323			reuseport = sk->sk_reuseport;
 324			if (reuseport) {
 325				hash = udp6_ehashfn(net, daddr, hnum,
 326						    saddr, sport);
 327				if (select_ok) {
 328					struct sock *sk2;
 329
 330					sk2 = reuseport_select_sock(sk, hash, skb,
 331							sizeof(struct udphdr));
 332					if (sk2) {
 333						result = sk2;
 334						select_ok = false;
 335						goto found;
 336					}
 337				}
 338				matches = 1;
 339			}
 340		} else if (score == badness && reuseport) {
 341			matches++;
 342			if (reciprocal_scale(hash, matches) == 0)
 343				result = sk;
 344			hash = next_pseudo_random32(hash);
 345		}
 346	}
 347	/*
 348	 * if the nulls value we got at the end of this lookup is
 349	 * not the expected one, we must restart lookup.
 350	 * We probably met an item that was moved to another chain.
 351	 */
 352	if (get_nulls_value(node) != slot)
 353		goto begin;
 354
 355	if (result) {
 356found:
 357		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 358			result = NULL;
 359		else if (unlikely(compute_score(result, net, hnum, saddr, sport,
 360					daddr, dport, dif) < badness)) {
 361			sock_put(result);
 362			goto begin;
 363		}
 364	}
 365	rcu_read_unlock();
 
 
 
 
 366	return result;
 367}
 368EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
 369
 370static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 371					  __be16 sport, __be16 dport,
 372					  struct udp_table *udptable)
 373{
 374	struct sock *sk;
 375	const struct ipv6hdr *iph = ipv6_hdr(skb);
 376
 377	sk = skb_steal_sock(skb);
 378	if (unlikely(sk))
 379		return sk;
 380	return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
 
 
 
 
 
 
 
 381				 &iph->daddr, dport, inet6_iif(skb),
 382				 udptable, skb);
 383}
 384
 
 
 
 
 385struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 386			     const struct in6_addr *daddr, __be16 dport, int dif)
 387{
 388	return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table, NULL);
 
 
 
 
 
 
 389}
 390EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 
 
 
 
 
 
 
 
 
 
 391
 392/*
 393 *	This should be easy, if there is something there we
 394 *	return it, otherwise we block.
 395 */
 396
 397int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 398		  int noblock, int flags, int *addr_len)
 399{
 400	struct ipv6_pinfo *np = inet6_sk(sk);
 401	struct inet_sock *inet = inet_sk(sk);
 402	struct sk_buff *skb;
 403	unsigned int ulen, copied;
 404	int peeked, off = 0;
 405	int err;
 406	int is_udplite = IS_UDPLITE(sk);
 
 407	bool checksum_valid = false;
 408	int is_udp4;
 409	bool slow;
 410
 411	if (flags & MSG_ERRQUEUE)
 412		return ipv6_recv_error(sk, msg, len, addr_len);
 413
 414	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 415		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 416
 417try_again:
 418	skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
 419				  &peeked, &off, &err);
 420	if (!skb)
 421		goto out;
 422
 423	ulen = skb->len - sizeof(struct udphdr);
 424	copied = len;
 425	if (copied > ulen)
 426		copied = ulen;
 427	else if (copied < ulen)
 428		msg->msg_flags |= MSG_TRUNC;
 429
 430	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 
 431
 432	/*
 433	 * If checksum is needed at all, try to do it while copying the
 434	 * data.  If the data is truncated, or if we only want a partial
 435	 * coverage checksum (UDP-Lite), do it before the copy.
 436	 */
 437
 438	if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
 439		checksum_valid = !udp_lib_checksum_complete(skb);
 
 
 440		if (!checksum_valid)
 441			goto csum_copy_err;
 442	}
 443
 444	if (checksum_valid || skb_csum_unnecessary(skb))
 445		err = skb_copy_datagram_msg(skb, sizeof(struct udphdr),
 446					    msg, copied);
 447	else {
 448		err = skb_copy_and_csum_datagram_msg(skb, sizeof(struct udphdr), msg);
 
 
 449		if (err == -EINVAL)
 450			goto csum_copy_err;
 451	}
 452	if (unlikely(err)) {
 453		trace_kfree_skb(skb, udpv6_recvmsg);
 454		if (!peeked) {
 455			atomic_inc(&sk->sk_drops);
 456			if (is_udp4)
 457				UDP_INC_STATS_USER(sock_net(sk),
 458						   UDP_MIB_INERRORS,
 459						   is_udplite);
 460			else
 461				UDP6_INC_STATS_USER(sock_net(sk),
 462						    UDP_MIB_INERRORS,
 463						    is_udplite);
 464		}
 465		goto out_free;
 466	}
 467	if (!peeked) {
 468		if (is_udp4)
 469			UDP_INC_STATS_USER(sock_net(sk),
 470					UDP_MIB_INDATAGRAMS, is_udplite);
 471		else
 472			UDP6_INC_STATS_USER(sock_net(sk),
 473					UDP_MIB_INDATAGRAMS, is_udplite);
 474	}
 
 
 475
 476	sock_recv_ts_and_drops(msg, sk, skb);
 477
 478	/* Copy the address. */
 479	if (msg->msg_name) {
 480		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 481		sin6->sin6_family = AF_INET6;
 482		sin6->sin6_port = udp_hdr(skb)->source;
 483		sin6->sin6_flowinfo = 0;
 484
 485		if (is_udp4) {
 486			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 487					       &sin6->sin6_addr);
 488			sin6->sin6_scope_id = 0;
 489		} else {
 490			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 491			sin6->sin6_scope_id =
 492				ipv6_iface_scope_id(&sin6->sin6_addr,
 493						    inet6_iif(skb));
 494		}
 495		*addr_len = sizeof(*sin6);
 
 
 
 496	}
 497
 
 
 
 498	if (np->rxopt.all)
 499		ip6_datagram_recv_common_ctl(sk, msg, skb);
 500
 501	if (is_udp4) {
 502		if (inet->cmsg_flags)
 503			ip_cmsg_recv(msg, skb);
 
 504	} else {
 505		if (np->rxopt.all)
 506			ip6_datagram_recv_specific_ctl(sk, msg, skb);
 507	}
 508
 509	err = copied;
 510	if (flags & MSG_TRUNC)
 511		err = ulen;
 512
 513out_free:
 514	skb_free_datagram_locked(sk, skb);
 515out:
 516	return err;
 517
 518csum_copy_err:
 519	slow = lock_sock_fast(sk);
 520	if (!skb_kill_datagram(sk, skb, flags)) {
 521		if (is_udp4) {
 522			UDP_INC_STATS_USER(sock_net(sk),
 523					UDP_MIB_CSUMERRORS, is_udplite);
 524			UDP_INC_STATS_USER(sock_net(sk),
 525					UDP_MIB_INERRORS, is_udplite);
 526		} else {
 527			UDP6_INC_STATS_USER(sock_net(sk),
 528					UDP_MIB_CSUMERRORS, is_udplite);
 529			UDP6_INC_STATS_USER(sock_net(sk),
 530					UDP_MIB_INERRORS, is_udplite);
 531		}
 532	}
 533	unlock_sock_fast(sk, slow);
 534
 535	/* starting over for a new packet, but check if we need to yield */
 536	cond_resched();
 537	msg->msg_flags &= ~MSG_TRUNC;
 538	goto try_again;
 539}
 540
 541void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 542		    u8 type, u8 code, int offset, __be32 info,
 543		    struct udp_table *udptable)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 544{
 545	struct ipv6_pinfo *np;
 546	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 547	const struct in6_addr *saddr = &hdr->saddr;
 548	const struct in6_addr *daddr = &hdr->daddr;
 549	struct udphdr *uh = (struct udphdr *)(skb->data+offset);
 
 550	struct sock *sk;
 551	int harderr;
 552	int err;
 553	struct net *net = dev_net(skb->dev);
 554
 555	sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
 556			       inet6_iif(skb), udptable, skb);
 557	if (!sk) {
 558		ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
 559				   ICMP6_MIB_INERRORS);
 560		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 561	}
 562
 563	harderr = icmpv6_err_convert(type, code, &err);
 564	np = inet6_sk(sk);
 565
 566	if (type == ICMPV6_PKT_TOOBIG) {
 567		if (!ip6_sk_accept_pmtu(sk))
 568			goto out;
 569		ip6_sk_update_pmtu(skb, sk, info);
 570		if (np->pmtudisc != IPV6_PMTUDISC_DONT)
 571			harderr = 1;
 572	}
 573	if (type == NDISC_REDIRECT) {
 574		ip6_sk_redirect(skb, sk);
 
 
 
 
 
 575		goto out;
 576	}
 577
 
 
 
 
 578	if (!np->recverr) {
 579		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 580			goto out;
 581	} else {
 582		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 583	}
 584
 585	sk->sk_err = err;
 586	sk->sk_error_report(sk);
 587out:
 588	sock_put(sk);
 589}
 590
 591static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 592{
 593	int rc;
 594
 595	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 596		sock_rps_save_rxhash(sk, skb);
 597		sk_mark_napi_id(sk, skb);
 598		sk_incoming_cpu_update(sk);
 
 
 599	}
 600
 601	rc = sock_queue_rcv_skb(sk, skb);
 602	if (rc < 0) {
 603		int is_udplite = IS_UDPLITE(sk);
 604
 605		/* Note that an ENOMEM error is charged twice */
 606		if (rc == -ENOMEM)
 607			UDP6_INC_STATS_BH(sock_net(sk),
 608					UDP_MIB_RCVBUFERRORS, is_udplite);
 609		UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 
 
 
 610		kfree_skb(skb);
 611		return -1;
 612	}
 613	return 0;
 614}
 615
 616static __inline__ void udpv6_err(struct sk_buff *skb,
 617				 struct inet6_skb_parm *opt, u8 type,
 618				 u8 code, int offset, __be32 info)
 619{
 620	__udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 621}
 622
 623static struct static_key udpv6_encap_needed __read_mostly;
 624void udpv6_encap_enable(void)
 
 625{
 626	if (!static_key_enabled(&udpv6_encap_needed))
 627		static_key_slow_inc(&udpv6_encap_needed);
 628}
 629EXPORT_SYMBOL(udpv6_encap_enable);
 630
 631int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 632{
 633	struct udp_sock *up = udp_sk(sk);
 634	int rc;
 635	int is_udplite = IS_UDPLITE(sk);
 636
 637	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 638		goto drop;
 639
 640	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
 641		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
 642
 643		/*
 644		 * This is an encapsulation socket so pass the skb to
 645		 * the socket's udp_encap_rcv() hook. Otherwise, just
 646		 * fall through and pass this up the UDP socket.
 647		 * up->encap_rcv() returns the following value:
 648		 * =0 if skb was successfully passed to the encap
 649		 *    handler or was discarded by it.
 650		 * >0 if skb should be passed on to UDP.
 651		 * <0 if skb should be resubmitted as proto -N
 652		 */
 653
 654		/* if we're overly short, let UDP handle it */
 655		encap_rcv = ACCESS_ONCE(up->encap_rcv);
 656		if (skb->len > sizeof(struct udphdr) && encap_rcv) {
 657			int ret;
 658
 659			/* Verify checksum before giving to encap */
 660			if (udp_lib_checksum_complete(skb))
 661				goto csum_error;
 662
 663			ret = encap_rcv(sk, skb);
 664			if (ret <= 0) {
 665				UDP_INC_STATS_BH(sock_net(sk),
 666						 UDP_MIB_INDATAGRAMS,
 667						 is_udplite);
 668				return -ret;
 669			}
 670		}
 671
 672		/* FALLTHROUGH -- it's a UDP Packet */
 673	}
 674
 675	/*
 676	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 677	 */
 678	if ((is_udplite & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 679
 680		if (up->pcrlen == 0) {          /* full coverage was set  */
 681			net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
 682					    UDP_SKB_CB(skb)->cscov, skb->len);
 683			goto drop;
 684		}
 685		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 686			net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
 687					    UDP_SKB_CB(skb)->cscov, up->pcrlen);
 688			goto drop;
 689		}
 690	}
 691
 692	if (rcu_access_pointer(sk->sk_filter)) {
 693		if (udp_lib_checksum_complete(skb))
 694			goto csum_error;
 695	}
 696
 697	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
 698		UDP6_INC_STATS_BH(sock_net(sk),
 699				  UDP_MIB_RCVBUFERRORS, is_udplite);
 700		goto drop;
 701	}
 702
 703	skb_dst_drop(skb);
 704
 705	bh_lock_sock(sk);
 706	rc = 0;
 707	if (!sock_owned_by_user(sk))
 708		rc = __udpv6_queue_rcv_skb(sk, skb);
 709	else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
 710		bh_unlock_sock(sk);
 711		goto drop;
 712	}
 713	bh_unlock_sock(sk);
 714
 715	return rc;
 716
 717csum_error:
 718	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 719drop:
 720	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 721	atomic_inc(&sk->sk_drops);
 722	kfree_skb(skb);
 723	return -1;
 724}
 725
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 726static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
 727				   __be16 loc_port, const struct in6_addr *loc_addr,
 728				   __be16 rmt_port, const struct in6_addr *rmt_addr,
 729				   int dif, unsigned short hnum)
 730{
 731	struct inet_sock *inet = inet_sk(sk);
 732
 733	if (!net_eq(sock_net(sk), net))
 734		return false;
 735
 736	if (udp_sk(sk)->udp_port_hash != hnum ||
 737	    sk->sk_family != PF_INET6 ||
 738	    (inet->inet_dport && inet->inet_dport != rmt_port) ||
 739	    (!ipv6_addr_any(&sk->sk_v6_daddr) &&
 740		    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
 741	    (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) ||
 742	    (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 743		    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
 744		return false;
 745	if (!inet6_mc_check(sk, loc_addr, rmt_addr))
 746		return false;
 747	return true;
 748}
 749
 750static void flush_stack(struct sock **stack, unsigned int count,
 751			struct sk_buff *skb, unsigned int final)
 752{
 753	struct sk_buff *skb1 = NULL;
 754	struct sock *sk;
 755	unsigned int i;
 756
 757	for (i = 0; i < count; i++) {
 758		sk = stack[i];
 759		if (likely(!skb1))
 760			skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
 761		if (!skb1) {
 762			atomic_inc(&sk->sk_drops);
 763			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
 764					  IS_UDPLITE(sk));
 765			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
 766					  IS_UDPLITE(sk));
 767		}
 768
 769		if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
 770			skb1 = NULL;
 771		sock_put(sk);
 772	}
 773	if (unlikely(skb1))
 774		kfree_skb(skb1);
 775}
 776
 777static void udp6_csum_zero_error(struct sk_buff *skb)
 778{
 779	/* RFC 2460 section 8.1 says that we SHOULD log
 780	 * this error. Well, it is reasonable.
 781	 */
 782	net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
 783			    &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
 784			    &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
 785}
 786
 787/*
 788 * Note: called only from the BH handler context,
 789 * so we don't need to lock the hashes.
 790 */
 791static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 792		const struct in6_addr *saddr, const struct in6_addr *daddr,
 793		struct udp_table *udptable, int proto)
 794{
 795	struct sock *sk, *stack[256 / sizeof(struct sock *)];
 796	const struct udphdr *uh = udp_hdr(skb);
 797	struct hlist_nulls_node *node;
 798	unsigned short hnum = ntohs(uh->dest);
 799	struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
 800	int dif = inet6_iif(skb);
 801	unsigned int count = 0, offset = offsetof(typeof(*sk), sk_nulls_node);
 802	unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
 803	bool inner_flushed = false;
 
 
 
 804
 805	if (use_hash2) {
 806		hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) &
 807			    udp_table.mask;
 808		hash2 = udp6_portaddr_hash(net, daddr, hnum) & udp_table.mask;
 809start_lookup:
 810		hslot = &udp_table.hash2[hash2];
 811		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 812	}
 813
 814	spin_lock(&hslot->lock);
 815	sk_nulls_for_each_entry_offset(sk, node, &hslot->head, offset) {
 816		if (__udp_v6_is_mcast_sock(net, sk,
 817					   uh->dest, daddr,
 818					   uh->source, saddr,
 819					   dif, hnum) &&
 820		    /* If zero checksum and no_check is not on for
 821		     * the socket then skip it.
 822		     */
 823		    (uh->check || udp_sk(sk)->no_check6_rx)) {
 824			if (unlikely(count == ARRAY_SIZE(stack))) {
 825				flush_stack(stack, count, skb, ~0);
 826				inner_flushed = true;
 827				count = 0;
 828			}
 829			stack[count++] = sk;
 830			sock_hold(sk);
 
 
 
 
 
 831		}
 832	}
 833
 834	spin_unlock(&hslot->lock);
 
 
 835
 836	/* Also lookup *:port if we are using hash2 and haven't done so yet. */
 837	if (use_hash2 && hash2 != hash2_any) {
 838		hash2 = hash2_any;
 839		goto start_lookup;
 840	}
 841
 842	if (count) {
 843		flush_stack(stack, count, skb, count - 1);
 
 844	} else {
 845		if (!inner_flushed)
 846			UDP6_INC_STATS_BH(net, UDP_MIB_IGNOREDMULTI,
 847					  proto == IPPROTO_UDPLITE);
 848		consume_skb(skb);
 
 
 
 
 
 
 
 
 
 849	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 850	return 0;
 851}
 852
 853int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 854		   int proto)
 855{
 
 856	struct net *net = dev_net(skb->dev);
 857	struct sock *sk;
 858	struct udphdr *uh;
 859	const struct in6_addr *saddr, *daddr;
 
 860	u32 ulen = 0;
 861
 862	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 863		goto discard;
 864
 865	saddr = &ipv6_hdr(skb)->saddr;
 866	daddr = &ipv6_hdr(skb)->daddr;
 867	uh = udp_hdr(skb);
 868
 869	ulen = ntohs(uh->len);
 870	if (ulen > skb->len)
 871		goto short_packet;
 872
 873	if (proto == IPPROTO_UDP) {
 874		/* UDP validates ulen. */
 875
 876		/* Check for jumbo payload */
 877		if (ulen == 0)
 878			ulen = skb->len;
 879
 880		if (ulen < sizeof(*uh))
 881			goto short_packet;
 882
 883		if (ulen < skb->len) {
 884			if (pskb_trim_rcsum(skb, ulen))
 885				goto short_packet;
 886			saddr = &ipv6_hdr(skb)->saddr;
 887			daddr = &ipv6_hdr(skb)->daddr;
 888			uh = udp_hdr(skb);
 889		}
 890	}
 891
 892	if (udp6_csum_init(skb, uh, proto))
 893		goto csum_error;
 894
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 895	/*
 896	 *	Multicast receive code
 897	 */
 898	if (ipv6_addr_is_multicast(daddr))
 899		return __udp6_lib_mcast_deliver(net, skb,
 900				saddr, daddr, udptable, proto);
 901
 902	/* Unicast */
 903
 904	/*
 905	 * check socket cache ... must talk to Alan about his plans
 906	 * for sock caches... i'll skip this for now.
 907	 */
 908	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
 909	if (sk) {
 910		int ret;
 911
 912		if (!uh->check && !udp_sk(sk)->no_check6_rx) {
 913			sock_put(sk);
 914			udp6_csum_zero_error(skb);
 915			goto csum_error;
 916		}
 917
 918		if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
 919			skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check,
 920						 ip6_compute_pseudo);
 921
 922		ret = udpv6_queue_rcv_skb(sk, skb);
 923		sock_put(sk);
 924
 925		/* a return value > 0 means to resubmit the input */
 926		if (ret > 0)
 927			return ret;
 928
 929		return 0;
 930	}
 931
 932	if (!uh->check) {
 933		udp6_csum_zero_error(skb);
 934		goto csum_error;
 935	}
 936
 937	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 938		goto discard;
 939
 940	if (udp_lib_checksum_complete(skb))
 941		goto csum_error;
 942
 943	UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
 944	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 945
 946	kfree_skb(skb);
 947	return 0;
 948
 949short_packet:
 950	net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
 951			    proto == IPPROTO_UDPLITE ? "-Lite" : "",
 952			    saddr, ntohs(uh->source),
 953			    ulen, skb->len,
 954			    daddr, ntohs(uh->dest));
 955	goto discard;
 
 
 
 956csum_error:
 957	UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
 958discard:
 959	UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
 960	kfree_skb(skb);
 961	return 0;
 962}
 963
 964static __inline__ int udpv6_rcv(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 965{
 966	return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
 967}
 968
 969/*
 970 * Throw away all pending data and cancel the corking. Socket is locked.
 971 */
 972static void udp_v6_flush_pending_frames(struct sock *sk)
 973{
 974	struct udp_sock *up = udp_sk(sk);
 975
 976	if (up->pending == AF_INET)
 977		udp_flush_pending_frames(sk);
 978	else if (up->pending) {
 979		up->len = 0;
 980		up->pending = 0;
 981		ip6_flush_pending_frames(sk);
 982	}
 983}
 984
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 985/**
 986 *	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
 987 *	@sk:	socket we are sending on
 988 *	@skb:	sk_buff containing the filled-in UDP header
 989 *		(checksum field must be zeroed out)
 
 
 
 990 */
 991static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
 992				 const struct in6_addr *saddr,
 993				 const struct in6_addr *daddr, int len)
 994{
 995	unsigned int offset;
 996	struct udphdr *uh = udp_hdr(skb);
 997	struct sk_buff *frags = skb_shinfo(skb)->frag_list;
 998	__wsum csum = 0;
 999
1000	if (!frags) {
1001		/* Only one fragment on the socket.  */
1002		skb->csum_start = skb_transport_header(skb) - skb->head;
1003		skb->csum_offset = offsetof(struct udphdr, check);
1004		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1005	} else {
1006		/*
1007		 * HW-checksum won't work as there are two or more
1008		 * fragments on the socket so that all csums of sk_buffs
1009		 * should be together
1010		 */
1011		offset = skb_transport_offset(skb);
1012		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
 
1013
1014		skb->ip_summed = CHECKSUM_NONE;
1015
1016		do {
1017			csum = csum_add(csum, frags->csum);
1018		} while ((frags = frags->next));
1019
1020		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1021					    csum);
1022		if (uh->check == 0)
1023			uh->check = CSUM_MANGLED_0;
1024	}
1025}
1026
1027/*
1028 *	Sending
1029 */
1030
1031static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6)
 
1032{
1033	struct sock *sk = skb->sk;
1034	struct udphdr *uh;
1035	int err = 0;
1036	int is_udplite = IS_UDPLITE(sk);
1037	__wsum csum = 0;
1038	int offset = skb_transport_offset(skb);
1039	int len = skb->len - offset;
 
1040
1041	/*
1042	 * Create a UDP header
1043	 */
1044	uh = udp_hdr(skb);
1045	uh->source = fl6->fl6_sport;
1046	uh->dest = fl6->fl6_dport;
1047	uh->len = htons(len);
1048	uh->check = 0;
1049
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1050	if (is_udplite)
1051		csum = udplite_csum(skb);
1052	else if (udp_sk(sk)->no_check6_tx) {   /* UDP csum disabled */
1053		skb->ip_summed = CHECKSUM_NONE;
1054		goto send;
1055	} else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
 
1056		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1057		goto send;
1058	} else
1059		csum = udp_csum(skb);
1060
1061	/* add protocol-dependent pseudo-header */
1062	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1063				    len, fl6->flowi6_proto, csum);
1064	if (uh->check == 0)
1065		uh->check = CSUM_MANGLED_0;
1066
1067send:
1068	err = ip6_send_skb(skb);
1069	if (err) {
1070		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1071			UDP6_INC_STATS_USER(sock_net(sk),
1072					    UDP_MIB_SNDBUFERRORS, is_udplite);
1073			err = 0;
1074		}
1075	} else
1076		UDP6_INC_STATS_USER(sock_net(sk),
1077				    UDP_MIB_OUTDATAGRAMS, is_udplite);
 
1078	return err;
1079}
1080
1081static int udp_v6_push_pending_frames(struct sock *sk)
1082{
1083	struct sk_buff *skb;
1084	struct udp_sock  *up = udp_sk(sk);
1085	struct flowi6 fl6;
1086	int err = 0;
1087
1088	if (up->pending == AF_INET)
1089		return udp_push_pending_frames(sk);
1090
1091	/* ip6_finish_skb will release the cork, so make a copy of
1092	 * fl6 here.
1093	 */
1094	fl6 = inet_sk(sk)->cork.fl.u.ip6;
1095
1096	skb = ip6_finish_skb(sk);
1097	if (!skb)
1098		goto out;
1099
1100	err = udp_v6_send_skb(skb, &fl6);
1101
1102out:
1103	up->len = 0;
1104	up->pending = 0;
1105	return err;
1106}
1107
1108int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1109{
1110	struct ipv6_txoptions opt_space;
1111	struct udp_sock *up = udp_sk(sk);
1112	struct inet_sock *inet = inet_sk(sk);
1113	struct ipv6_pinfo *np = inet6_sk(sk);
1114	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1115	struct in6_addr *daddr, *final_p, final;
1116	struct ipv6_txoptions *opt = NULL;
1117	struct ipv6_txoptions *opt_to_free = NULL;
1118	struct ip6_flowlabel *flowlabel = NULL;
1119	struct flowi6 fl6;
1120	struct dst_entry *dst;
 
1121	int addr_len = msg->msg_namelen;
 
1122	int ulen = len;
1123	int hlimit = -1;
1124	int tclass = -1;
1125	int dontfrag = -1;
1126	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1127	int err;
1128	int connected = 0;
1129	int is_udplite = IS_UDPLITE(sk);
1130	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1131
 
 
 
 
 
1132	/* destination address check */
1133	if (sin6) {
1134		if (addr_len < offsetof(struct sockaddr, sa_data))
1135			return -EINVAL;
1136
1137		switch (sin6->sin6_family) {
1138		case AF_INET6:
1139			if (addr_len < SIN6_LEN_RFC2133)
1140				return -EINVAL;
1141			daddr = &sin6->sin6_addr;
 
 
 
 
1142			break;
1143		case AF_INET:
1144			goto do_udp_sendmsg;
1145		case AF_UNSPEC:
1146			msg->msg_name = sin6 = NULL;
1147			msg->msg_namelen = addr_len = 0;
1148			daddr = NULL;
1149			break;
1150		default:
1151			return -EINVAL;
1152		}
1153	} else if (!up->pending) {
1154		if (sk->sk_state != TCP_ESTABLISHED)
1155			return -EDESTADDRREQ;
1156		daddr = &sk->sk_v6_daddr;
1157	} else
1158		daddr = NULL;
1159
1160	if (daddr) {
1161		if (ipv6_addr_v4mapped(daddr)) {
1162			struct sockaddr_in sin;
1163			sin.sin_family = AF_INET;
1164			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1165			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1166			msg->msg_name = &sin;
1167			msg->msg_namelen = sizeof(sin);
1168do_udp_sendmsg:
1169			if (__ipv6_only_sock(sk))
1170				return -ENETUNREACH;
1171			return udp_sendmsg(sk, msg, len);
1172		}
1173	}
1174
1175	if (up->pending == AF_INET)
1176		return udp_sendmsg(sk, msg, len);
1177
1178	/* Rough check on arithmetic overflow,
1179	   better check is made in ip6_append_data().
1180	   */
1181	if (len > INT_MAX - sizeof(struct udphdr))
1182		return -EMSGSIZE;
1183
1184	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1185	if (up->pending) {
1186		/*
1187		 * There are pending frames.
1188		 * The socket lock must be held while it's corked.
1189		 */
1190		lock_sock(sk);
1191		if (likely(up->pending)) {
1192			if (unlikely(up->pending != AF_INET6)) {
1193				release_sock(sk);
1194				return -EAFNOSUPPORT;
1195			}
1196			dst = NULL;
1197			goto do_append_data;
1198		}
1199		release_sock(sk);
1200	}
1201	ulen += sizeof(struct udphdr);
1202
1203	memset(&fl6, 0, sizeof(fl6));
1204
1205	if (sin6) {
1206		if (sin6->sin6_port == 0)
1207			return -EINVAL;
1208
1209		fl6.fl6_dport = sin6->sin6_port;
1210		daddr = &sin6->sin6_addr;
1211
1212		if (np->sndflow) {
1213			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1214			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1215				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1216				if (!flowlabel)
1217					return -EINVAL;
1218			}
1219		}
1220
1221		/*
1222		 * Otherwise it will be difficult to maintain
1223		 * sk->sk_dst_cache.
1224		 */
1225		if (sk->sk_state == TCP_ESTABLISHED &&
1226		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1227			daddr = &sk->sk_v6_daddr;
1228
1229		if (addr_len >= sizeof(struct sockaddr_in6) &&
1230		    sin6->sin6_scope_id &&
1231		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1232			fl6.flowi6_oif = sin6->sin6_scope_id;
1233	} else {
1234		if (sk->sk_state != TCP_ESTABLISHED)
1235			return -EDESTADDRREQ;
1236
1237		fl6.fl6_dport = inet->inet_dport;
1238		daddr = &sk->sk_v6_daddr;
1239		fl6.flowlabel = np->flow_label;
1240		connected = 1;
1241	}
1242
1243	if (!fl6.flowi6_oif)
1244		fl6.flowi6_oif = sk->sk_bound_dev_if;
1245
1246	if (!fl6.flowi6_oif)
1247		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1248
1249	fl6.flowi6_mark = sk->sk_mark;
 
1250
1251	if (msg->msg_controllen) {
1252		opt = &opt_space;
1253		memset(opt, 0, sizeof(struct ipv6_txoptions));
1254		opt->tot_len = sizeof(*opt);
 
1255
1256		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1257					    &hlimit, &tclass, &dontfrag);
 
 
1258		if (err < 0) {
1259			fl6_sock_release(flowlabel);
1260			return err;
1261		}
1262		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1263			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1264			if (!flowlabel)
1265				return -EINVAL;
1266		}
1267		if (!(opt->opt_nflen|opt->opt_flen))
1268			opt = NULL;
1269		connected = 0;
1270	}
1271	if (!opt) {
1272		opt = txopt_get(np);
1273		opt_to_free = opt;
1274	}
1275	if (flowlabel)
1276		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1277	opt = ipv6_fixup_options(&opt_space, opt);
 
1278
1279	fl6.flowi6_proto = sk->sk_protocol;
1280	if (!ipv6_addr_any(daddr))
1281		fl6.daddr = *daddr;
1282	else
1283		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1284	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1285		fl6.saddr = np->saddr;
1286	fl6.fl6_sport = inet->inet_sport;
1287
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1288	final_p = fl6_update_dst(&fl6, opt, &final);
1289	if (final_p)
1290		connected = 0;
1291
1292	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1293		fl6.flowi6_oif = np->mcast_oif;
1294		connected = 0;
1295	} else if (!fl6.flowi6_oif)
1296		fl6.flowi6_oif = np->ucast_oif;
1297
1298	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 
 
 
1299
1300	dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
 
 
1301	if (IS_ERR(dst)) {
1302		err = PTR_ERR(dst);
1303		dst = NULL;
1304		goto out;
1305	}
1306
1307	if (hlimit < 0)
1308		hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1309
1310	if (tclass < 0)
1311		tclass = np->tclass;
1312
1313	if (msg->msg_flags&MSG_CONFIRM)
1314		goto do_confirm;
1315back_from_confirm:
1316
1317	/* Lockless fast path for the non-corking case */
1318	if (!corkreq) {
 
1319		struct sk_buff *skb;
1320
1321		skb = ip6_make_skb(sk, getfrag, msg, ulen,
1322				   sizeof(struct udphdr), hlimit, tclass, opt,
1323				   &fl6, (struct rt6_info *)dst,
1324				   msg->msg_flags, dontfrag);
1325		err = PTR_ERR(skb);
1326		if (!IS_ERR_OR_NULL(skb))
1327			err = udp_v6_send_skb(skb, &fl6);
1328		goto release_dst;
1329	}
1330
1331	lock_sock(sk);
1332	if (unlikely(up->pending)) {
1333		/* The socket is already corked while preparing it. */
1334		/* ... which is an evident application bug. --ANK */
1335		release_sock(sk);
1336
1337		net_dbg_ratelimited("udp cork app bug 2\n");
1338		err = -EINVAL;
1339		goto out;
1340	}
1341
1342	up->pending = AF_INET6;
1343
1344do_append_data:
1345	if (dontfrag < 0)
1346		dontfrag = np->dontfrag;
1347	up->len += ulen;
1348	err = ip6_append_data(sk, getfrag, msg, ulen,
1349		sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1350		(struct rt6_info *)dst,
1351		corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1352	if (err)
1353		udp_v6_flush_pending_frames(sk);
1354	else if (!corkreq)
1355		err = udp_v6_push_pending_frames(sk);
1356	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1357		up->pending = 0;
1358
1359	if (err > 0)
1360		err = np->recverr ? net_xmit_errno(err) : 0;
1361	release_sock(sk);
1362
1363release_dst:
1364	if (dst) {
1365		if (connected) {
1366			ip6_dst_store(sk, dst,
1367				      ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
1368				      &sk->sk_v6_daddr : NULL,
1369#ifdef CONFIG_IPV6_SUBTREES
1370				      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1371				      &np->saddr :
1372#endif
1373				      NULL);
1374		} else {
1375			dst_release(dst);
1376		}
1377		dst = NULL;
1378	}
1379
1380out:
1381	dst_release(dst);
 
1382	fl6_sock_release(flowlabel);
1383	txopt_put(opt_to_free);
1384	if (!err)
1385		return len;
1386	/*
1387	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1388	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1389	 * we don't have a good statistic (IpOutDiscards but it can be too many
1390	 * things).  We could add another new stat but at least for now that
1391	 * seems like overkill.
1392	 */
1393	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1394		UDP6_INC_STATS_USER(sock_net(sk),
1395				UDP_MIB_SNDBUFERRORS, is_udplite);
1396	}
1397	return err;
1398
1399do_confirm:
1400	dst_confirm(dst);
 
1401	if (!(msg->msg_flags&MSG_PROBE) || len)
1402		goto back_from_confirm;
1403	err = 0;
1404	goto out;
1405}
1406
1407void udpv6_destroy_sock(struct sock *sk)
1408{
1409	struct udp_sock *up = udp_sk(sk);
1410	lock_sock(sk);
 
 
 
1411	udp_v6_flush_pending_frames(sk);
1412	release_sock(sk);
1413
1414	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1415		void (*encap_destroy)(struct sock *sk);
1416		encap_destroy = ACCESS_ONCE(up->encap_destroy);
1417		if (encap_destroy)
1418			encap_destroy(sk);
 
 
 
 
 
 
1419	}
1420
1421	inet6_destroy_sock(sk);
1422}
1423
1424/*
1425 *	Socket option code for UDP
1426 */
1427int udpv6_setsockopt(struct sock *sk, int level, int optname,
1428		     char __user *optval, unsigned int optlen)
1429{
1430	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1431		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
 
1432					  udp_v6_push_pending_frames);
1433	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1434}
1435
1436#ifdef CONFIG_COMPAT
1437int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1438			    char __user *optval, unsigned int optlen)
1439{
1440	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1441		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1442					  udp_v6_push_pending_frames);
1443	return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1444}
1445#endif
1446
1447int udpv6_getsockopt(struct sock *sk, int level, int optname,
1448		     char __user *optval, int __user *optlen)
1449{
1450	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1451		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1452	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1453}
1454
1455#ifdef CONFIG_COMPAT
1456int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1457			    char __user *optval, int __user *optlen)
1458{
1459	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1460		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1461	return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1462}
1463#endif
1464
1465static const struct inet6_protocol udpv6_protocol = {
1466	.handler	=	udpv6_rcv,
1467	.err_handler	=	udpv6_err,
1468	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1469};
1470
1471/* ------------------------------------------------------------------------ */
1472#ifdef CONFIG_PROC_FS
1473int udp6_seq_show(struct seq_file *seq, void *v)
1474{
1475	if (v == SEQ_START_TOKEN) {
1476		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1477	} else {
1478		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1479		struct inet_sock *inet = inet_sk(v);
1480		__u16 srcp = ntohs(inet->inet_sport);
1481		__u16 destp = ntohs(inet->inet_dport);
1482		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
 
1483	}
1484	return 0;
1485}
1486
1487static const struct file_operations udp6_afinfo_seq_fops = {
1488	.owner    = THIS_MODULE,
1489	.open     = udp_seq_open,
1490	.read     = seq_read,
1491	.llseek   = seq_lseek,
1492	.release  = seq_release_net
1493};
 
1494
1495static struct udp_seq_afinfo udp6_seq_afinfo = {
1496	.name		= "udp6",
1497	.family		= AF_INET6,
1498	.udp_table	= &udp_table,
1499	.seq_fops	= &udp6_afinfo_seq_fops,
1500	.seq_ops	= {
1501		.show		= udp6_seq_show,
1502	},
1503};
1504
1505int __net_init udp6_proc_init(struct net *net)
1506{
1507	return udp_proc_register(net, &udp6_seq_afinfo);
 
 
 
1508}
1509
1510void udp6_proc_exit(struct net *net)
1511{
1512	udp_proc_unregister(net, &udp6_seq_afinfo);
1513}
1514#endif /* CONFIG_PROC_FS */
1515
1516void udp_v6_clear_sk(struct sock *sk, int size)
1517{
1518	struct inet_sock *inet = inet_sk(sk);
1519
1520	/* we do not want to clear pinet6 field, because of RCU lookups */
1521	sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6));
1522
1523	size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
1524	memset(&inet->pinet6 + 1, 0, size);
1525}
1526
1527/* ------------------------------------------------------------------------ */
1528
1529struct proto udpv6_prot = {
1530	.name		   = "UDPv6",
1531	.owner		   = THIS_MODULE,
1532	.close		   = udp_lib_close,
1533	.connect	   = ip6_datagram_connect,
1534	.disconnect	   = udp_disconnect,
1535	.ioctl		   = udp_ioctl,
1536	.destroy	   = udpv6_destroy_sock,
1537	.setsockopt	   = udpv6_setsockopt,
1538	.getsockopt	   = udpv6_getsockopt,
1539	.sendmsg	   = udpv6_sendmsg,
1540	.recvmsg	   = udpv6_recvmsg,
1541	.backlog_rcv	   = __udpv6_queue_rcv_skb,
1542	.release_cb	   = ip6_datagram_release_cb,
1543	.hash		   = udp_lib_hash,
1544	.unhash		   = udp_lib_unhash,
1545	.rehash		   = udp_v6_rehash,
1546	.get_port	   = udp_v6_get_port,
1547	.memory_allocated  = &udp_memory_allocated,
1548	.sysctl_mem	   = sysctl_udp_mem,
1549	.sysctl_wmem	   = &sysctl_udp_wmem_min,
1550	.sysctl_rmem	   = &sysctl_udp_rmem_min,
1551	.obj_size	   = sizeof(struct udp6_sock),
1552	.slab_flags	   = SLAB_DESTROY_BY_RCU,
1553	.h.udp_table	   = &udp_table,
1554#ifdef CONFIG_COMPAT
1555	.compat_setsockopt = compat_udpv6_setsockopt,
1556	.compat_getsockopt = compat_udpv6_getsockopt,
1557#endif
1558	.clear_sk	   = udp_v6_clear_sk,
 
 
 
 
 
 
1559};
1560
1561static struct inet_protosw udpv6_protosw = {
1562	.type =      SOCK_DGRAM,
1563	.protocol =  IPPROTO_UDP,
1564	.prot =      &udpv6_prot,
1565	.ops =       &inet6_dgram_ops,
1566	.flags =     INET_PROTOSW_PERMANENT,
1567};
1568
1569int __init udpv6_init(void)
1570{
1571	int ret;
1572
1573	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1574	if (ret)
1575		goto out;
1576
1577	ret = inet6_register_protosw(&udpv6_protosw);
1578	if (ret)
1579		goto out_udpv6_protocol;
1580out:
1581	return ret;
1582
1583out_udpv6_protocol:
1584	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1585	goto out;
1586}
1587
1588void udpv6_exit(void)
1589{
1590	inet6_unregister_protosw(&udpv6_protosw);
1591	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1592}
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	UDP over IPv6
   4 *	Linux INET6 implementation
   5 *
   6 *	Authors:
   7 *	Pedro Roque		<roque@di.fc.ul.pt>
   8 *
   9 *	Based on linux/ipv4/udp.c
  10 *
  11 *	Fixes:
  12 *	Hideaki YOSHIFUJI	:	sin6_scope_id support
  13 *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
  14 *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
  15 *					a single port at the same time.
  16 *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
  17 *      YOSHIFUJI Hideaki @USAGI:	convert /proc/net/udp6 to seq_file.
 
 
 
 
 
  18 */
  19
  20#include <linux/errno.h>
  21#include <linux/types.h>
  22#include <linux/socket.h>
  23#include <linux/sockios.h>
  24#include <linux/net.h>
  25#include <linux/in6.h>
  26#include <linux/netdevice.h>
  27#include <linux/if_arp.h>
  28#include <linux/ipv6.h>
  29#include <linux/icmpv6.h>
  30#include <linux/init.h>
  31#include <linux/module.h>
  32#include <linux/skbuff.h>
  33#include <linux/slab.h>
  34#include <linux/uaccess.h>
  35#include <linux/indirect_call_wrapper.h>
  36
  37#include <net/addrconf.h>
  38#include <net/ndisc.h>
  39#include <net/protocol.h>
  40#include <net/transp_v6.h>
  41#include <net/ip6_route.h>
  42#include <net/raw.h>
  43#include <net/tcp_states.h>
  44#include <net/ip6_checksum.h>
  45#include <net/ip6_tunnel.h>
  46#include <net/xfrm.h>
  47#include <net/inet_hashtables.h>
  48#include <net/inet6_hashtables.h>
  49#include <net/busy_poll.h>
  50#include <net/sock_reuseport.h>
  51
  52#include <linux/proc_fs.h>
  53#include <linux/seq_file.h>
  54#include <trace/events/skb.h>
  55#include "udp_impl.h"
  56
  57static u32 udp6_ehashfn(const struct net *net,
  58			const struct in6_addr *laddr,
  59			const u16 lport,
  60			const struct in6_addr *faddr,
  61			const __be16 fport)
  62{
  63	static u32 udp6_ehash_secret __read_mostly;
  64	static u32 udp_ipv6_hash_secret __read_mostly;
  65
  66	u32 lhash, fhash;
  67
  68	net_get_random_once(&udp6_ehash_secret,
  69			    sizeof(udp6_ehash_secret));
  70	net_get_random_once(&udp_ipv6_hash_secret,
  71			    sizeof(udp_ipv6_hash_secret));
  72
  73	lhash = (__force u32)laddr->s6_addr32[3];
  74	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
  75
  76	return __inet6_ehashfn(lhash, lport, fhash, fport,
  77			       udp_ipv6_hash_secret + net_hash_mix(net));
  78}
  79
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  80int udp_v6_get_port(struct sock *sk, unsigned short snum)
  81{
  82	unsigned int hash2_nulladdr =
  83		ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
  84	unsigned int hash2_partial =
  85		ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
  86
  87	/* precompute partial secondary hash */
  88	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
  89	return udp_lib_get_port(sk, snum, hash2_nulladdr);
  90}
  91
  92void udp_v6_rehash(struct sock *sk)
  93{
  94	u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
  95					  &sk->sk_v6_rcv_saddr,
  96					  inet_sk(sk)->inet_num);
  97
  98	udp_lib_rehash(sk, new_hash);
  99}
 100
 101static int compute_score(struct sock *sk, struct net *net,
 102			 const struct in6_addr *saddr, __be16 sport,
 103			 const struct in6_addr *daddr, unsigned short hnum,
 104			 int dif, int sdif)
 
 105{
 106	int score;
 107	struct inet_sock *inet;
 108	bool dev_match;
 109
 110	if (!net_eq(sock_net(sk), net) ||
 111	    udp_sk(sk)->udp_port_hash != hnum ||
 112	    sk->sk_family != PF_INET6)
 113		return -1;
 114
 115	if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 116		return -1;
 117
 118	score = 0;
 119	inet = inet_sk(sk);
 120
 121	if (inet->inet_dport) {
 122		if (inet->inet_dport != sport)
 123			return -1;
 124		score++;
 125	}
 126
 
 
 
 
 
 
 127	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 128		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 129			return -1;
 130		score++;
 131	}
 132
 133	dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif);
 134	if (!dev_match)
 135		return -1;
 136	if (sk->sk_bound_dev_if)
 137		score++;
 
 138
 139	if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
 140		score++;
 141
 142	return score;
 143}
 144
 145static struct sock *lookup_reuseport(struct net *net, struct sock *sk,
 146				     struct sk_buff *skb,
 147				     const struct in6_addr *saddr,
 148				     __be16 sport,
 149				     const struct in6_addr *daddr,
 150				     unsigned int hnum)
 151{
 152	struct sock *reuse_sk = NULL;
 153	u32 hash;
 154
 155	if (sk->sk_reuseport && sk->sk_state != TCP_ESTABLISHED) {
 156		hash = udp6_ehashfn(net, daddr, hnum, saddr, sport);
 157		reuse_sk = reuseport_select_sock(sk, hash, skb,
 158						 sizeof(struct udphdr));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 159	}
 160	return reuse_sk;
 
 
 
 
 
 
 
 
 
 
 161}
 162
 163/* called with rcu_read_lock() */
 164static struct sock *udp6_lib_lookup2(struct net *net,
 165		const struct in6_addr *saddr, __be16 sport,
 166		const struct in6_addr *daddr, unsigned int hnum,
 167		int dif, int sdif, struct udp_hslot *hslot2,
 168		struct sk_buff *skb)
 169{
 170	struct sock *sk, *result;
 171	int score, badness;
 
 
 
 172
 
 173	result = NULL;
 174	badness = -1;
 175	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
 176		score = compute_score(sk, net, saddr, sport,
 177				      daddr, hnum, dif, sdif);
 178		if (score > badness) {
 179			result = lookup_reuseport(net, sk, skb,
 180						  saddr, sport, daddr, hnum);
 181			/* Fall back to scoring if group has connections */
 182			if (result && !reuseport_has_conns(sk, false))
 183				return result;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 184
 185			result = result ? : sk;
 186			badness = score;
 
 
 
 
 
 
 187		}
 188	}
 189	return result;
 190}
 191
 192static inline struct sock *udp6_lookup_run_bpf(struct net *net,
 193					       struct udp_table *udptable,
 194					       struct sk_buff *skb,
 195					       const struct in6_addr *saddr,
 196					       __be16 sport,
 197					       const struct in6_addr *daddr,
 198					       u16 hnum)
 199{
 200	struct sock *sk, *reuse_sk;
 201	bool no_reuseport;
 202
 203	if (udptable != &udp_table)
 204		return NULL; /* only UDP is supported */
 205
 206	no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP,
 207					    saddr, sport, daddr, hnum, &sk);
 208	if (no_reuseport || IS_ERR_OR_NULL(sk))
 209		return sk;
 210
 211	reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
 212	if (reuse_sk)
 213		sk = reuse_sk;
 214	return sk;
 215}
 216
 217/* rcu_read_lock() must be held */
 218struct sock *__udp6_lib_lookup(struct net *net,
 219			       const struct in6_addr *saddr, __be16 sport,
 220			       const struct in6_addr *daddr, __be16 dport,
 221			       int dif, int sdif, struct udp_table *udptable,
 222			       struct sk_buff *skb)
 223{
 
 
 224	unsigned short hnum = ntohs(dport);
 225	unsigned int hash2, slot2;
 226	struct udp_hslot *hslot2;
 227	struct sock *result, *sk;
 228
 229	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
 230	slot2 = hash2 & udptable->mask;
 231	hslot2 = &udptable->hash2[slot2];
 232
 233	/* Lookup connected or non-wildcard sockets */
 234	result = udp6_lib_lookup2(net, saddr, sport,
 235				  daddr, hnum, dif, sdif,
 236				  hslot2, skb);
 237	if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
 238		goto done;
 239
 240	/* Lookup redirect from BPF */
 241	if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
 242		sk = udp6_lookup_run_bpf(net, udptable, skb,
 243					 saddr, sport, daddr, hnum);
 244		if (sk) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 245			result = sk;
 246			goto done;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 247		}
 248	}
 
 
 
 
 
 
 
 249
 250	/* Got non-wildcard socket or error on first lookup */
 251	if (result)
 252		goto done;
 253
 254	/* Lookup wildcard sockets */
 255	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
 256	slot2 = hash2 & udptable->mask;
 257	hslot2 = &udptable->hash2[slot2];
 258
 259	result = udp6_lib_lookup2(net, saddr, sport,
 260				  &in6addr_any, hnum, dif, sdif,
 261				  hslot2, skb);
 262done:
 263	if (IS_ERR(result))
 264		return NULL;
 265	return result;
 266}
 267EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
 268
 269static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 270					  __be16 sport, __be16 dport,
 271					  struct udp_table *udptable)
 272{
 
 273	const struct ipv6hdr *iph = ipv6_hdr(skb);
 274
 275	return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
 276				 &iph->daddr, dport, inet6_iif(skb),
 277				 inet6_sdif(skb), udptable, skb);
 278}
 279
 280struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
 281				 __be16 sport, __be16 dport)
 282{
 283	const struct ipv6hdr *iph = ipv6_hdr(skb);
 284
 285	return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
 286				 &iph->daddr, dport, inet6_iif(skb),
 287				 inet6_sdif(skb), &udp_table, NULL);
 288}
 289
 290/* Must be called under rcu_read_lock().
 291 * Does increment socket refcount.
 292 */
 293#if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
 294struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 295			     const struct in6_addr *daddr, __be16 dport, int dif)
 296{
 297	struct sock *sk;
 298
 299	sk =  __udp6_lib_lookup(net, saddr, sport, daddr, dport,
 300				dif, 0, &udp_table, NULL);
 301	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
 302		sk = NULL;
 303	return sk;
 304}
 305EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 306#endif
 307
 308/* do not use the scratch area len for jumbogram: their length execeeds the
 309 * scratch area space; note that the IP6CB flags is still in the first
 310 * cacheline, so checking for jumbograms is cheap
 311 */
 312static int udp6_skb_len(struct sk_buff *skb)
 313{
 314	return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
 315}
 316
 317/*
 318 *	This should be easy, if there is something there we
 319 *	return it, otherwise we block.
 320 */
 321
 322int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 323		  int noblock, int flags, int *addr_len)
 324{
 325	struct ipv6_pinfo *np = inet6_sk(sk);
 326	struct inet_sock *inet = inet_sk(sk);
 327	struct sk_buff *skb;
 328	unsigned int ulen, copied;
 329	int off, err, peeking = flags & MSG_PEEK;
 
 330	int is_udplite = IS_UDPLITE(sk);
 331	struct udp_mib __percpu *mib;
 332	bool checksum_valid = false;
 333	int is_udp4;
 
 334
 335	if (flags & MSG_ERRQUEUE)
 336		return ipv6_recv_error(sk, msg, len, addr_len);
 337
 338	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 339		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 340
 341try_again:
 342	off = sk_peek_offset(sk, flags);
 343	skb = __skb_recv_udp(sk, flags, noblock, &off, &err);
 344	if (!skb)
 345		return err;
 346
 347	ulen = udp6_skb_len(skb);
 348	copied = len;
 349	if (copied > ulen - off)
 350		copied = ulen - off;
 351	else if (copied < ulen)
 352		msg->msg_flags |= MSG_TRUNC;
 353
 354	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 355	mib = __UDPX_MIB(sk, is_udp4);
 356
 357	/*
 358	 * If checksum is needed at all, try to do it while copying the
 359	 * data.  If the data is truncated, or if we only want a partial
 360	 * coverage checksum (UDP-Lite), do it before the copy.
 361	 */
 362
 363	if (copied < ulen || peeking ||
 364	    (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
 365		checksum_valid = udp_skb_csum_unnecessary(skb) ||
 366				!__udp_lib_checksum_complete(skb);
 367		if (!checksum_valid)
 368			goto csum_copy_err;
 369	}
 370
 371	if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
 372		if (udp_skb_is_linear(skb))
 373			err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
 374		else
 375			err = skb_copy_datagram_msg(skb, off, msg, copied);
 376	} else {
 377		err = skb_copy_and_csum_datagram_msg(skb, off, msg);
 378		if (err == -EINVAL)
 379			goto csum_copy_err;
 380	}
 381	if (unlikely(err)) {
 382		if (!peeking) {
 
 383			atomic_inc(&sk->sk_drops);
 384			SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 385		}
 386		kfree_skb(skb);
 387		return err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 388	}
 389	if (!peeking)
 390		SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS);
 391
 392	sock_recv_ts_and_drops(msg, sk, skb);
 393
 394	/* Copy the address. */
 395	if (msg->msg_name) {
 396		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 397		sin6->sin6_family = AF_INET6;
 398		sin6->sin6_port = udp_hdr(skb)->source;
 399		sin6->sin6_flowinfo = 0;
 400
 401		if (is_udp4) {
 402			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 403					       &sin6->sin6_addr);
 404			sin6->sin6_scope_id = 0;
 405		} else {
 406			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 407			sin6->sin6_scope_id =
 408				ipv6_iface_scope_id(&sin6->sin6_addr,
 409						    inet6_iif(skb));
 410		}
 411		*addr_len = sizeof(*sin6);
 412
 413		BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk,
 414						      (struct sockaddr *)sin6);
 415	}
 416
 417	if (udp_sk(sk)->gro_enabled)
 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)
 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 = &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 || 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 (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				     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		goto out;
 618
 619	if (!np->recverr) {
 620		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 621			goto out;
 622	} else {
 623		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 624	}
 625
 626	sk->sk_err = err;
 627	sk_error_report(sk);
 628out:
 629	return 0;
 630}
 631
 632static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 633{
 634	int rc;
 635
 636	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 637		sock_rps_save_rxhash(sk, skb);
 638		sk_mark_napi_id(sk, skb);
 639		sk_incoming_cpu_update(sk);
 640	} else {
 641		sk_mark_napi_id_once(sk, skb);
 642	}
 643
 644	rc = __udp_enqueue_schedule_skb(sk, skb);
 645	if (rc < 0) {
 646		int is_udplite = IS_UDPLITE(sk);
 647
 648		/* Note that an ENOMEM error is charged twice */
 649		if (rc == -ENOMEM)
 650			UDP6_INC_STATS(sock_net(sk),
 651					 UDP_MIB_RCVBUFERRORS, is_udplite);
 652		else
 653			UDP6_INC_STATS(sock_net(sk),
 654				       UDP_MIB_MEMERRORS, is_udplite);
 655		UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 656		kfree_skb(skb);
 657		return -1;
 658	}
 
 
 659
 660	return 0;
 
 
 
 
 661}
 662
 663static __inline__ int udpv6_err(struct sk_buff *skb,
 664				struct inet6_skb_parm *opt, u8 type,
 665				u8 code, int offset, __be32 info)
 666{
 667	return __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 
 668}
 
 669
 670static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
 671{
 672	struct udp_sock *up = udp_sk(sk);
 
 673	int is_udplite = IS_UDPLITE(sk);
 674
 675	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 676		goto drop;
 677
 678	if (static_branch_unlikely(&udpv6_encap_needed_key) && up->encap_type) {
 679		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
 680
 681		/*
 682		 * This is an encapsulation socket so pass the skb to
 683		 * the socket's udp_encap_rcv() hook. Otherwise, just
 684		 * fall through and pass this up the UDP socket.
 685		 * up->encap_rcv() returns the following value:
 686		 * =0 if skb was successfully passed to the encap
 687		 *    handler or was discarded by it.
 688		 * >0 if skb should be passed on to UDP.
 689		 * <0 if skb should be resubmitted as proto -N
 690		 */
 691
 692		/* if we're overly short, let UDP handle it */
 693		encap_rcv = READ_ONCE(up->encap_rcv);
 694		if (encap_rcv) {
 695			int ret;
 696
 697			/* Verify checksum before giving to encap */
 698			if (udp_lib_checksum_complete(skb))
 699				goto csum_error;
 700
 701			ret = encap_rcv(sk, skb);
 702			if (ret <= 0) {
 703				__UDP_INC_STATS(sock_net(sk),
 704						UDP_MIB_INDATAGRAMS,
 705						is_udplite);
 706				return -ret;
 707			}
 708		}
 709
 710		/* FALLTHROUGH -- it's a UDP Packet */
 711	}
 712
 713	/*
 714	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 715	 */
 716	if ((up->pcflag & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 717
 718		if (up->pcrlen == 0) {          /* full coverage was set  */
 719			net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
 720					    UDP_SKB_CB(skb)->cscov, skb->len);
 721			goto drop;
 722		}
 723		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 724			net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
 725					    UDP_SKB_CB(skb)->cscov, up->pcrlen);
 726			goto drop;
 727		}
 728	}
 729
 730	prefetch(&sk->sk_rmem_alloc);
 731	if (rcu_access_pointer(sk->sk_filter) &&
 732	    udp_lib_checksum_complete(skb))
 733		goto csum_error;
 734
 735	if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
 
 
 736		goto drop;
 
 737
 738	udp_csum_pull_header(skb);
 739
 740	skb_dst_drop(skb);
 
 
 
 
 
 
 
 
 741
 742	return __udpv6_queue_rcv_skb(sk, skb);
 743
 744csum_error:
 745	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 746drop:
 747	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 748	atomic_inc(&sk->sk_drops);
 749	kfree_skb(skb);
 750	return -1;
 751}
 752
 753static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 754{
 755	struct sk_buff *next, *segs;
 756	int ret;
 757
 758	if (likely(!udp_unexpected_gso(sk, skb)))
 759		return udpv6_queue_rcv_one_skb(sk, skb);
 760
 761	__skb_push(skb, -skb_mac_offset(skb));
 762	segs = udp_rcv_segment(sk, skb, false);
 763	skb_list_walk_safe(segs, skb, next) {
 764		__skb_pull(skb, skb_transport_offset(skb));
 765
 766		udp_post_segment_fix_csum(skb);
 767		ret = udpv6_queue_rcv_one_skb(sk, skb);
 768		if (ret > 0)
 769			ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret,
 770						 true);
 771	}
 772	return 0;
 773}
 774
 775static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
 776				   __be16 loc_port, const struct in6_addr *loc_addr,
 777				   __be16 rmt_port, const struct in6_addr *rmt_addr,
 778				   int dif, int sdif, unsigned short hnum)
 779{
 780	struct inet_sock *inet = inet_sk(sk);
 781
 782	if (!net_eq(sock_net(sk), net))
 783		return false;
 784
 785	if (udp_sk(sk)->udp_port_hash != hnum ||
 786	    sk->sk_family != PF_INET6 ||
 787	    (inet->inet_dport && inet->inet_dport != rmt_port) ||
 788	    (!ipv6_addr_any(&sk->sk_v6_daddr) &&
 789		    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
 790	    !udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif) ||
 791	    (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 792		    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
 793		return false;
 794	if (!inet6_mc_check(sk, loc_addr, rmt_addr))
 795		return false;
 796	return true;
 797}
 798
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 799static void udp6_csum_zero_error(struct sk_buff *skb)
 800{
 801	/* RFC 2460 section 8.1 says that we SHOULD log
 802	 * this error. Well, it is reasonable.
 803	 */
 804	net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
 805			    &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
 806			    &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
 807}
 808
 809/*
 810 * Note: called only from the BH handler context,
 811 * so we don't need to lock the hashes.
 812 */
 813static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 814		const struct in6_addr *saddr, const struct in6_addr *daddr,
 815		struct udp_table *udptable, int proto)
 816{
 817	struct sock *sk, *first = NULL;
 818	const struct udphdr *uh = udp_hdr(skb);
 
 819	unsigned short hnum = ntohs(uh->dest);
 820	struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
 821	unsigned int offset = offsetof(typeof(*sk), sk_node);
 
 822	unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
 823	int dif = inet6_iif(skb);
 824	int sdif = inet6_sdif(skb);
 825	struct hlist_node *node;
 826	struct sk_buff *nskb;
 827
 828	if (use_hash2) {
 829		hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
 830			    udptable->mask;
 831		hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
 832start_lookup:
 833		hslot = &udptable->hash2[hash2];
 834		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 835	}
 836
 837	sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
 838		if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
 839					    uh->source, saddr, dif, sdif,
 840					    hnum))
 841			continue;
 842		/* If zero checksum and no_check is not on for
 843		 * the socket then skip it.
 844		 */
 845		if (!uh->check && !udp_sk(sk)->no_check6_rx)
 846			continue;
 847		if (!first) {
 848			first = sk;
 849			continue;
 850		}
 851		nskb = skb_clone(skb, GFP_ATOMIC);
 852		if (unlikely(!nskb)) {
 853			atomic_inc(&sk->sk_drops);
 854			__UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
 855					 IS_UDPLITE(sk));
 856			__UDP6_INC_STATS(net, UDP_MIB_INERRORS,
 857					 IS_UDPLITE(sk));
 858			continue;
 859		}
 
 860
 861		if (udpv6_queue_rcv_skb(sk, nskb) > 0)
 862			consume_skb(nskb);
 863	}
 864
 865	/* Also lookup *:port if we are using hash2 and haven't done so yet. */
 866	if (use_hash2 && hash2 != hash2_any) {
 867		hash2 = hash2_any;
 868		goto start_lookup;
 869	}
 870
 871	if (first) {
 872		if (udpv6_queue_rcv_skb(first, skb) > 0)
 873			consume_skb(skb);
 874	} else {
 875		kfree_skb(skb);
 876		__UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
 877				 proto == IPPROTO_UDPLITE);
 878	}
 879	return 0;
 880}
 881
 882static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
 883{
 884	if (udp_sk_rx_dst_set(sk, dst)) {
 885		const struct rt6_info *rt = (const struct rt6_info *)dst;
 886
 887		inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt);
 888	}
 889}
 890
 891/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
 892 * return code conversion for ip layer consumption
 893 */
 894static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
 895				struct udphdr *uh)
 896{
 897	int ret;
 898
 899	if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
 900		skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo);
 901
 902	ret = udpv6_queue_rcv_skb(sk, skb);
 903
 904	/* a return value > 0 means to resubmit the input */
 905	if (ret > 0)
 906		return ret;
 907	return 0;
 908}
 909
 910int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 911		   int proto)
 912{
 913	const struct in6_addr *saddr, *daddr;
 914	struct net *net = dev_net(skb->dev);
 
 915	struct udphdr *uh;
 916	struct sock *sk;
 917	bool refcounted;
 918	u32 ulen = 0;
 919
 920	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 921		goto discard;
 922
 923	saddr = &ipv6_hdr(skb)->saddr;
 924	daddr = &ipv6_hdr(skb)->daddr;
 925	uh = udp_hdr(skb);
 926
 927	ulen = ntohs(uh->len);
 928	if (ulen > skb->len)
 929		goto short_packet;
 930
 931	if (proto == IPPROTO_UDP) {
 932		/* UDP validates ulen. */
 933
 934		/* Check for jumbo payload */
 935		if (ulen == 0)
 936			ulen = skb->len;
 937
 938		if (ulen < sizeof(*uh))
 939			goto short_packet;
 940
 941		if (ulen < skb->len) {
 942			if (pskb_trim_rcsum(skb, ulen))
 943				goto short_packet;
 944			saddr = &ipv6_hdr(skb)->saddr;
 945			daddr = &ipv6_hdr(skb)->daddr;
 946			uh = udp_hdr(skb);
 947		}
 948	}
 949
 950	if (udp6_csum_init(skb, uh, proto))
 951		goto csum_error;
 952
 953	/* Check if the socket is already available, e.g. due to early demux */
 954	sk = skb_steal_sock(skb, &refcounted);
 955	if (sk) {
 956		struct dst_entry *dst = skb_dst(skb);
 957		int ret;
 958
 959		if (unlikely(sk->sk_rx_dst != dst))
 960			udp6_sk_rx_dst_set(sk, dst);
 961
 962		if (!uh->check && !udp_sk(sk)->no_check6_rx) {
 963			if (refcounted)
 964				sock_put(sk);
 965			goto report_csum_error;
 966		}
 967
 968		ret = udp6_unicast_rcv_skb(sk, skb, uh);
 969		if (refcounted)
 970			sock_put(sk);
 971		return ret;
 972	}
 973
 974	/*
 975	 *	Multicast receive code
 976	 */
 977	if (ipv6_addr_is_multicast(daddr))
 978		return __udp6_lib_mcast_deliver(net, skb,
 979				saddr, daddr, udptable, proto);
 980
 981	/* Unicast */
 
 
 
 
 
 982	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
 983	if (sk) {
 984		if (!uh->check && !udp_sk(sk)->no_check6_rx)
 985			goto report_csum_error;
 986		return udp6_unicast_rcv_skb(sk, skb, uh);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 987	}
 988
 989	if (!uh->check)
 990		goto report_csum_error;
 
 
 991
 992	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 993		goto discard;
 994
 995	if (udp_lib_checksum_complete(skb))
 996		goto csum_error;
 997
 998	__UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
 999	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
1000
1001	kfree_skb(skb);
1002	return 0;
1003
1004short_packet:
1005	net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
1006			    proto == IPPROTO_UDPLITE ? "-Lite" : "",
1007			    saddr, ntohs(uh->source),
1008			    ulen, skb->len,
1009			    daddr, ntohs(uh->dest));
1010	goto discard;
1011
1012report_csum_error:
1013	udp6_csum_zero_error(skb);
1014csum_error:
1015	__UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
1016discard:
1017	__UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
1018	kfree_skb(skb);
1019	return 0;
1020}
1021
1022
1023static struct sock *__udp6_lib_demux_lookup(struct net *net,
1024			__be16 loc_port, const struct in6_addr *loc_addr,
1025			__be16 rmt_port, const struct in6_addr *rmt_addr,
1026			int dif, int sdif)
1027{
1028	unsigned short hnum = ntohs(loc_port);
1029	unsigned int hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
1030	unsigned int slot2 = hash2 & udp_table.mask;
1031	struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
1032	const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
1033	struct sock *sk;
1034
1035	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
1036		if (sk->sk_state == TCP_ESTABLISHED &&
1037		    INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif, sdif))
1038			return sk;
1039		/* Only check first socket in chain */
1040		break;
1041	}
1042	return NULL;
1043}
1044
1045INDIRECT_CALLABLE_SCOPE void udp_v6_early_demux(struct sk_buff *skb)
1046{
1047	struct net *net = dev_net(skb->dev);
1048	const struct udphdr *uh;
1049	struct sock *sk;
1050	struct dst_entry *dst;
1051	int dif = skb->dev->ifindex;
1052	int sdif = inet6_sdif(skb);
1053
1054	if (!pskb_may_pull(skb, skb_transport_offset(skb) +
1055	    sizeof(struct udphdr)))
1056		return;
1057
1058	uh = udp_hdr(skb);
1059
1060	if (skb->pkt_type == PACKET_HOST)
1061		sk = __udp6_lib_demux_lookup(net, uh->dest,
1062					     &ipv6_hdr(skb)->daddr,
1063					     uh->source, &ipv6_hdr(skb)->saddr,
1064					     dif, sdif);
1065	else
1066		return;
1067
1068	if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
1069		return;
1070
1071	skb->sk = sk;
1072	skb->destructor = sock_efree;
1073	dst = READ_ONCE(sk->sk_rx_dst);
1074
1075	if (dst)
1076		dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);
1077	if (dst) {
1078		/* set noref for now.
1079		 * any place which wants to hold dst has to call
1080		 * dst_hold_safe()
1081		 */
1082		skb_dst_set_noref(skb, dst);
1083	}
1084}
1085
1086INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb)
1087{
1088	return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
1089}
1090
1091/*
1092 * Throw away all pending data and cancel the corking. Socket is locked.
1093 */
1094static void udp_v6_flush_pending_frames(struct sock *sk)
1095{
1096	struct udp_sock *up = udp_sk(sk);
1097
1098	if (up->pending == AF_INET)
1099		udp_flush_pending_frames(sk);
1100	else if (up->pending) {
1101		up->len = 0;
1102		up->pending = 0;
1103		ip6_flush_pending_frames(sk);
1104	}
1105}
1106
1107static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
1108			     int addr_len)
1109{
1110	if (addr_len < offsetofend(struct sockaddr, sa_family))
1111		return -EINVAL;
1112	/* The following checks are replicated from __ip6_datagram_connect()
1113	 * and intended to prevent BPF program called below from accessing
1114	 * bytes that are out of the bound specified by user in addr_len.
1115	 */
1116	if (uaddr->sa_family == AF_INET) {
1117		if (__ipv6_only_sock(sk))
1118			return -EAFNOSUPPORT;
1119		return udp_pre_connect(sk, uaddr, addr_len);
1120	}
1121
1122	if (addr_len < SIN6_LEN_RFC2133)
1123		return -EINVAL;
1124
1125	return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr);
1126}
1127
1128/**
1129 *	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
1130 *	@sk:	socket we are sending on
1131 *	@skb:	sk_buff containing the filled-in UDP header
1132 *		(checksum field must be zeroed out)
1133 *	@saddr: source address
1134 *	@daddr: destination address
1135 *	@len:	length of packet
1136 */
1137static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
1138				 const struct in6_addr *saddr,
1139				 const struct in6_addr *daddr, int len)
1140{
1141	unsigned int offset;
1142	struct udphdr *uh = udp_hdr(skb);
1143	struct sk_buff *frags = skb_shinfo(skb)->frag_list;
1144	__wsum csum = 0;
1145
1146	if (!frags) {
1147		/* Only one fragment on the socket.  */
1148		skb->csum_start = skb_transport_header(skb) - skb->head;
1149		skb->csum_offset = offsetof(struct udphdr, check);
1150		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1151	} else {
1152		/*
1153		 * HW-checksum won't work as there are two or more
1154		 * fragments on the socket so that all csums of sk_buffs
1155		 * should be together
1156		 */
1157		offset = skb_transport_offset(skb);
1158		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1159		csum = skb->csum;
1160
1161		skb->ip_summed = CHECKSUM_NONE;
1162
1163		do {
1164			csum = csum_add(csum, frags->csum);
1165		} while ((frags = frags->next));
1166
1167		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1168					    csum);
1169		if (uh->check == 0)
1170			uh->check = CSUM_MANGLED_0;
1171	}
1172}
1173
1174/*
1175 *	Sending
1176 */
1177
1178static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
1179			   struct inet_cork *cork)
1180{
1181	struct sock *sk = skb->sk;
1182	struct udphdr *uh;
1183	int err = 0;
1184	int is_udplite = IS_UDPLITE(sk);
1185	__wsum csum = 0;
1186	int offset = skb_transport_offset(skb);
1187	int len = skb->len - offset;
1188	int datalen = len - sizeof(*uh);
1189
1190	/*
1191	 * Create a UDP header
1192	 */
1193	uh = udp_hdr(skb);
1194	uh->source = fl6->fl6_sport;
1195	uh->dest = fl6->fl6_dport;
1196	uh->len = htons(len);
1197	uh->check = 0;
1198
1199	if (cork->gso_size) {
1200		const int hlen = skb_network_header_len(skb) +
1201				 sizeof(struct udphdr);
1202
1203		if (hlen + cork->gso_size > cork->fragsize) {
1204			kfree_skb(skb);
1205			return -EINVAL;
1206		}
1207		if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) {
1208			kfree_skb(skb);
1209			return -EINVAL;
1210		}
1211		if (udp_sk(sk)->no_check6_tx) {
1212			kfree_skb(skb);
1213			return -EINVAL;
1214		}
1215		if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
1216		    dst_xfrm(skb_dst(skb))) {
1217			kfree_skb(skb);
1218			return -EIO;
1219		}
1220
1221		if (datalen > cork->gso_size) {
1222			skb_shinfo(skb)->gso_size = cork->gso_size;
1223			skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
1224			skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
1225								 cork->gso_size);
1226		}
1227		goto csum_partial;
1228	}
1229
1230	if (is_udplite)
1231		csum = udplite_csum(skb);
1232	else if (udp_sk(sk)->no_check6_tx) {   /* UDP csum disabled */
1233		skb->ip_summed = CHECKSUM_NONE;
1234		goto send;
1235	} else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1236csum_partial:
1237		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1238		goto send;
1239	} else
1240		csum = udp_csum(skb);
1241
1242	/* add protocol-dependent pseudo-header */
1243	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1244				    len, fl6->flowi6_proto, csum);
1245	if (uh->check == 0)
1246		uh->check = CSUM_MANGLED_0;
1247
1248send:
1249	err = ip6_send_skb(skb);
1250	if (err) {
1251		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1252			UDP6_INC_STATS(sock_net(sk),
1253				       UDP_MIB_SNDBUFERRORS, is_udplite);
1254			err = 0;
1255		}
1256	} else {
1257		UDP6_INC_STATS(sock_net(sk),
1258			       UDP_MIB_OUTDATAGRAMS, is_udplite);
1259	}
1260	return err;
1261}
1262
1263static int udp_v6_push_pending_frames(struct sock *sk)
1264{
1265	struct sk_buff *skb;
1266	struct udp_sock  *up = udp_sk(sk);
1267	struct flowi6 fl6;
1268	int err = 0;
1269
1270	if (up->pending == AF_INET)
1271		return udp_push_pending_frames(sk);
1272
1273	/* ip6_finish_skb will release the cork, so make a copy of
1274	 * fl6 here.
1275	 */
1276	fl6 = inet_sk(sk)->cork.fl.u.ip6;
1277
1278	skb = ip6_finish_skb(sk);
1279	if (!skb)
1280		goto out;
1281
1282	err = udp_v6_send_skb(skb, &fl6, &inet_sk(sk)->cork.base);
1283
1284out:
1285	up->len = 0;
1286	up->pending = 0;
1287	return err;
1288}
1289
1290int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1291{
1292	struct ipv6_txoptions opt_space;
1293	struct udp_sock *up = udp_sk(sk);
1294	struct inet_sock *inet = inet_sk(sk);
1295	struct ipv6_pinfo *np = inet6_sk(sk);
1296	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1297	struct in6_addr *daddr, *final_p, final;
1298	struct ipv6_txoptions *opt = NULL;
1299	struct ipv6_txoptions *opt_to_free = NULL;
1300	struct ip6_flowlabel *flowlabel = NULL;
1301	struct flowi6 fl6;
1302	struct dst_entry *dst;
1303	struct ipcm6_cookie ipc6;
1304	int addr_len = msg->msg_namelen;
1305	bool connected = false;
1306	int ulen = len;
1307	int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE;
 
 
 
1308	int err;
 
1309	int is_udplite = IS_UDPLITE(sk);
1310	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1311
1312	ipcm6_init(&ipc6);
1313	ipc6.gso_size = READ_ONCE(up->gso_size);
1314	ipc6.sockc.tsflags = sk->sk_tsflags;
1315	ipc6.sockc.mark = sk->sk_mark;
1316
1317	/* destination address check */
1318	if (sin6) {
1319		if (addr_len < offsetof(struct sockaddr, sa_data))
1320			return -EINVAL;
1321
1322		switch (sin6->sin6_family) {
1323		case AF_INET6:
1324			if (addr_len < SIN6_LEN_RFC2133)
1325				return -EINVAL;
1326			daddr = &sin6->sin6_addr;
1327			if (ipv6_addr_any(daddr) &&
1328			    ipv6_addr_v4mapped(&np->saddr))
1329				ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1330						       daddr);
1331			break;
1332		case AF_INET:
1333			goto do_udp_sendmsg;
1334		case AF_UNSPEC:
1335			msg->msg_name = sin6 = NULL;
1336			msg->msg_namelen = addr_len = 0;
1337			daddr = NULL;
1338			break;
1339		default:
1340			return -EINVAL;
1341		}
1342	} else if (!up->pending) {
1343		if (sk->sk_state != TCP_ESTABLISHED)
1344			return -EDESTADDRREQ;
1345		daddr = &sk->sk_v6_daddr;
1346	} else
1347		daddr = NULL;
1348
1349	if (daddr) {
1350		if (ipv6_addr_v4mapped(daddr)) {
1351			struct sockaddr_in sin;
1352			sin.sin_family = AF_INET;
1353			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1354			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1355			msg->msg_name = &sin;
1356			msg->msg_namelen = sizeof(sin);
1357do_udp_sendmsg:
1358			if (__ipv6_only_sock(sk))
1359				return -ENETUNREACH;
1360			return udp_sendmsg(sk, msg, len);
1361		}
1362	}
1363
1364	if (up->pending == AF_INET)
1365		return udp_sendmsg(sk, msg, len);
1366
1367	/* Rough check on arithmetic overflow,
1368	   better check is made in ip6_append_data().
1369	   */
1370	if (len > INT_MAX - sizeof(struct udphdr))
1371		return -EMSGSIZE;
1372
1373	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1374	if (up->pending) {
1375		/*
1376		 * There are pending frames.
1377		 * The socket lock must be held while it's corked.
1378		 */
1379		lock_sock(sk);
1380		if (likely(up->pending)) {
1381			if (unlikely(up->pending != AF_INET6)) {
1382				release_sock(sk);
1383				return -EAFNOSUPPORT;
1384			}
1385			dst = NULL;
1386			goto do_append_data;
1387		}
1388		release_sock(sk);
1389	}
1390	ulen += sizeof(struct udphdr);
1391
1392	memset(&fl6, 0, sizeof(fl6));
1393
1394	if (sin6) {
1395		if (sin6->sin6_port == 0)
1396			return -EINVAL;
1397
1398		fl6.fl6_dport = sin6->sin6_port;
1399		daddr = &sin6->sin6_addr;
1400
1401		if (np->sndflow) {
1402			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1403			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1404				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1405				if (IS_ERR(flowlabel))
1406					return -EINVAL;
1407			}
1408		}
1409
1410		/*
1411		 * Otherwise it will be difficult to maintain
1412		 * sk->sk_dst_cache.
1413		 */
1414		if (sk->sk_state == TCP_ESTABLISHED &&
1415		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1416			daddr = &sk->sk_v6_daddr;
1417
1418		if (addr_len >= sizeof(struct sockaddr_in6) &&
1419		    sin6->sin6_scope_id &&
1420		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1421			fl6.flowi6_oif = sin6->sin6_scope_id;
1422	} else {
1423		if (sk->sk_state != TCP_ESTABLISHED)
1424			return -EDESTADDRREQ;
1425
1426		fl6.fl6_dport = inet->inet_dport;
1427		daddr = &sk->sk_v6_daddr;
1428		fl6.flowlabel = np->flow_label;
1429		connected = true;
1430	}
1431
1432	if (!fl6.flowi6_oif)
1433		fl6.flowi6_oif = sk->sk_bound_dev_if;
1434
1435	if (!fl6.flowi6_oif)
1436		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1437
1438	fl6.flowi6_mark = ipc6.sockc.mark;
1439	fl6.flowi6_uid = sk->sk_uid;
1440
1441	if (msg->msg_controllen) {
1442		opt = &opt_space;
1443		memset(opt, 0, sizeof(struct ipv6_txoptions));
1444		opt->tot_len = sizeof(*opt);
1445		ipc6.opt = opt;
1446
1447		err = udp_cmsg_send(sk, msg, &ipc6.gso_size);
1448		if (err > 0)
1449			err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6,
1450						    &ipc6);
1451		if (err < 0) {
1452			fl6_sock_release(flowlabel);
1453			return err;
1454		}
1455		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1456			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1457			if (IS_ERR(flowlabel))
1458				return -EINVAL;
1459		}
1460		if (!(opt->opt_nflen|opt->opt_flen))
1461			opt = NULL;
1462		connected = false;
1463	}
1464	if (!opt) {
1465		opt = txopt_get(np);
1466		opt_to_free = opt;
1467	}
1468	if (flowlabel)
1469		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1470	opt = ipv6_fixup_options(&opt_space, opt);
1471	ipc6.opt = opt;
1472
1473	fl6.flowi6_proto = sk->sk_protocol;
1474	fl6.daddr = *daddr;
 
 
 
1475	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1476		fl6.saddr = np->saddr;
1477	fl6.fl6_sport = inet->inet_sport;
1478
1479	if (cgroup_bpf_enabled(BPF_CGROUP_UDP6_SENDMSG) && !connected) {
1480		err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk,
1481					   (struct sockaddr *)sin6, &fl6.saddr);
1482		if (err)
1483			goto out_no_dst;
1484		if (sin6) {
1485			if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
1486				/* BPF program rewrote IPv6-only by IPv4-mapped
1487				 * IPv6. It's currently unsupported.
1488				 */
1489				err = -ENOTSUPP;
1490				goto out_no_dst;
1491			}
1492			if (sin6->sin6_port == 0) {
1493				/* BPF program set invalid port. Reject it. */
1494				err = -EINVAL;
1495				goto out_no_dst;
1496			}
1497			fl6.fl6_dport = sin6->sin6_port;
1498			fl6.daddr = sin6->sin6_addr;
1499		}
1500	}
1501
1502	if (ipv6_addr_any(&fl6.daddr))
1503		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1504
1505	final_p = fl6_update_dst(&fl6, opt, &final);
1506	if (final_p)
1507		connected = false;
1508
1509	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1510		fl6.flowi6_oif = np->mcast_oif;
1511		connected = false;
1512	} else if (!fl6.flowi6_oif)
1513		fl6.flowi6_oif = np->ucast_oif;
1514
1515	security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
1516
1517	if (ipc6.tclass < 0)
1518		ipc6.tclass = np->tclass;
1519
1520	fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
1521
1522	dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, connected);
1523	if (IS_ERR(dst)) {
1524		err = PTR_ERR(dst);
1525		dst = NULL;
1526		goto out;
1527	}
1528
1529	if (ipc6.hlimit < 0)
1530		ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 
 
 
1531
1532	if (msg->msg_flags&MSG_CONFIRM)
1533		goto do_confirm;
1534back_from_confirm:
1535
1536	/* Lockless fast path for the non-corking case */
1537	if (!corkreq) {
1538		struct inet_cork_full cork;
1539		struct sk_buff *skb;
1540
1541		skb = ip6_make_skb(sk, getfrag, msg, ulen,
1542				   sizeof(struct udphdr), &ipc6,
1543				   &fl6, (struct rt6_info *)dst,
1544				   msg->msg_flags, &cork);
1545		err = PTR_ERR(skb);
1546		if (!IS_ERR_OR_NULL(skb))
1547			err = udp_v6_send_skb(skb, &fl6, &cork.base);
1548		goto out;
1549	}
1550
1551	lock_sock(sk);
1552	if (unlikely(up->pending)) {
1553		/* The socket is already corked while preparing it. */
1554		/* ... which is an evident application bug. --ANK */
1555		release_sock(sk);
1556
1557		net_dbg_ratelimited("udp cork app bug 2\n");
1558		err = -EINVAL;
1559		goto out;
1560	}
1561
1562	up->pending = AF_INET6;
1563
1564do_append_data:
1565	if (ipc6.dontfrag < 0)
1566		ipc6.dontfrag = np->dontfrag;
1567	up->len += ulen;
1568	err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1569			      &ipc6, &fl6, (struct rt6_info *)dst,
1570			      corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
 
1571	if (err)
1572		udp_v6_flush_pending_frames(sk);
1573	else if (!corkreq)
1574		err = udp_v6_push_pending_frames(sk);
1575	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1576		up->pending = 0;
1577
1578	if (err > 0)
1579		err = np->recverr ? net_xmit_errno(err) : 0;
1580	release_sock(sk);
1581
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1582out:
1583	dst_release(dst);
1584out_no_dst:
1585	fl6_sock_release(flowlabel);
1586	txopt_put(opt_to_free);
1587	if (!err)
1588		return len;
1589	/*
1590	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1591	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1592	 * we don't have a good statistic (IpOutDiscards but it can be too many
1593	 * things).  We could add another new stat but at least for now that
1594	 * seems like overkill.
1595	 */
1596	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1597		UDP6_INC_STATS(sock_net(sk),
1598			       UDP_MIB_SNDBUFERRORS, is_udplite);
1599	}
1600	return err;
1601
1602do_confirm:
1603	if (msg->msg_flags & MSG_PROBE)
1604		dst_confirm_neigh(dst, &fl6.daddr);
1605	if (!(msg->msg_flags&MSG_PROBE) || len)
1606		goto back_from_confirm;
1607	err = 0;
1608	goto out;
1609}
1610
1611void udpv6_destroy_sock(struct sock *sk)
1612{
1613	struct udp_sock *up = udp_sk(sk);
1614	lock_sock(sk);
1615
1616	/* protects from races with udp_abort() */
1617	sock_set_flag(sk, SOCK_DEAD);
1618	udp_v6_flush_pending_frames(sk);
1619	release_sock(sk);
1620
1621	if (static_branch_unlikely(&udpv6_encap_needed_key)) {
1622		if (up->encap_type) {
1623			void (*encap_destroy)(struct sock *sk);
1624			encap_destroy = READ_ONCE(up->encap_destroy);
1625			if (encap_destroy)
1626				encap_destroy(sk);
1627		}
1628		if (up->encap_enabled) {
1629			static_branch_dec(&udpv6_encap_needed_key);
1630			udp_encap_disable();
1631		}
1632	}
1633
1634	inet6_destroy_sock(sk);
1635}
1636
1637/*
1638 *	Socket option code for UDP
1639 */
1640int udpv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1641		     unsigned int optlen)
1642{
1643	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1644		return udp_lib_setsockopt(sk, level, optname,
1645					  optval, optlen,
1646					  udp_v6_push_pending_frames);
1647	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1648}
1649
 
 
 
 
 
 
 
 
 
 
 
1650int udpv6_getsockopt(struct sock *sk, int level, int optname,
1651		     char __user *optval, int __user *optlen)
1652{
1653	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1654		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1655	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1656}
1657
1658/* thinking of making this const? Don't.
1659 * early_demux can change based on sysctl.
1660 */
1661static struct inet6_protocol udpv6_protocol = {
1662	.early_demux	=	udp_v6_early_demux,
1663	.early_demux_handler =  udp_v6_early_demux,
 
 
 
 
 
1664	.handler	=	udpv6_rcv,
1665	.err_handler	=	udpv6_err,
1666	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1667};
1668
1669/* ------------------------------------------------------------------------ */
1670#ifdef CONFIG_PROC_FS
1671int udp6_seq_show(struct seq_file *seq, void *v)
1672{
1673	if (v == SEQ_START_TOKEN) {
1674		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1675	} else {
1676		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1677		struct inet_sock *inet = inet_sk(v);
1678		__u16 srcp = ntohs(inet->inet_sport);
1679		__u16 destp = ntohs(inet->inet_dport);
1680		__ip6_dgram_sock_seq_show(seq, v, srcp, destp,
1681					  udp_rqueue_get(v), bucket);
1682	}
1683	return 0;
1684}
1685
1686const struct seq_operations udp6_seq_ops = {
1687	.start		= udp_seq_start,
1688	.next		= udp_seq_next,
1689	.stop		= udp_seq_stop,
1690	.show		= udp6_seq_show,
 
1691};
1692EXPORT_SYMBOL(udp6_seq_ops);
1693
1694static struct udp_seq_afinfo udp6_seq_afinfo = {
 
1695	.family		= AF_INET6,
1696	.udp_table	= &udp_table,
 
 
 
 
1697};
1698
1699int __net_init udp6_proc_init(struct net *net)
1700{
1701	if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops,
1702			sizeof(struct udp_iter_state), &udp6_seq_afinfo))
1703		return -ENOMEM;
1704	return 0;
1705}
1706
1707void udp6_proc_exit(struct net *net)
1708{
1709	remove_proc_entry("udp6", net->proc_net);
1710}
1711#endif /* CONFIG_PROC_FS */
1712
 
 
 
 
 
 
 
 
 
 
 
1713/* ------------------------------------------------------------------------ */
1714
1715struct proto udpv6_prot = {
1716	.name			= "UDPv6",
1717	.owner			= THIS_MODULE,
1718	.close			= udp_lib_close,
1719	.pre_connect		= udpv6_pre_connect,
1720	.connect		= ip6_datagram_connect,
1721	.disconnect		= udp_disconnect,
1722	.ioctl			= udp_ioctl,
1723	.init			= udp_init_sock,
1724	.destroy		= udpv6_destroy_sock,
1725	.setsockopt		= udpv6_setsockopt,
1726	.getsockopt		= udpv6_getsockopt,
1727	.sendmsg		= udpv6_sendmsg,
1728	.recvmsg		= udpv6_recvmsg,
1729	.release_cb		= ip6_datagram_release_cb,
1730	.hash			= udp_lib_hash,
1731	.unhash			= udp_lib_unhash,
1732	.rehash			= udp_v6_rehash,
1733	.get_port		= udp_v6_get_port,
1734#ifdef CONFIG_BPF_SYSCALL
1735	.psock_update_sk_prot	= udp_bpf_update_proto,
 
 
 
 
 
 
 
1736#endif
1737	.memory_allocated	= &udp_memory_allocated,
1738	.sysctl_mem		= sysctl_udp_mem,
1739	.sysctl_wmem_offset     = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1740	.sysctl_rmem_offset     = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1741	.obj_size		= sizeof(struct udp6_sock),
1742	.h.udp_table		= &udp_table,
1743	.diag_destroy		= udp_abort,
1744};
1745
1746static struct inet_protosw udpv6_protosw = {
1747	.type =      SOCK_DGRAM,
1748	.protocol =  IPPROTO_UDP,
1749	.prot =      &udpv6_prot,
1750	.ops =       &inet6_dgram_ops,
1751	.flags =     INET_PROTOSW_PERMANENT,
1752};
1753
1754int __init udpv6_init(void)
1755{
1756	int ret;
1757
1758	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1759	if (ret)
1760		goto out;
1761
1762	ret = inet6_register_protosw(&udpv6_protosw);
1763	if (ret)
1764		goto out_udpv6_protocol;
1765out:
1766	return ret;
1767
1768out_udpv6_protocol:
1769	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1770	goto out;
1771}
1772
1773void udpv6_exit(void)
1774{
1775	inet6_unregister_protosw(&udpv6_protosw);
1776	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1777}