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v3.1
 
   1/*
   2 *	UDP over IPv6
   3 *	Linux INET6 implementation
   4 *
   5 *	Authors:
   6 *	Pedro Roque		<roque@di.fc.ul.pt>
   7 *
   8 *	Based on linux/ipv4/udp.c
   9 *
  10 *	Fixes:
  11 *	Hideaki YOSHIFUJI	:	sin6_scope_id support
  12 *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
  13 *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
  14 *					a single port at the same time.
  15 *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
  16 *      YOSHIFUJI Hideaki @USAGI:	convert /proc/net/udp6 to seq_file.
  17 *
  18 *	This program is free software; you can redistribute it and/or
  19 *      modify it under the terms of the GNU General Public License
  20 *      as published by the Free Software Foundation; either version
  21 *      2 of the License, or (at your option) any later version.
  22 */
  23
 
  24#include <linux/errno.h>
  25#include <linux/types.h>
  26#include <linux/socket.h>
  27#include <linux/sockios.h>
  28#include <linux/net.h>
  29#include <linux/in6.h>
  30#include <linux/netdevice.h>
  31#include <linux/if_arp.h>
  32#include <linux/ipv6.h>
  33#include <linux/icmpv6.h>
  34#include <linux/init.h>
  35#include <linux/module.h>
  36#include <linux/skbuff.h>
  37#include <linux/slab.h>
  38#include <asm/uaccess.h>
 
  39
 
  40#include <net/ndisc.h>
  41#include <net/protocol.h>
  42#include <net/transp_v6.h>
  43#include <net/ip6_route.h>
  44#include <net/raw.h>
 
  45#include <net/tcp_states.h>
  46#include <net/ip6_checksum.h>
 
  47#include <net/xfrm.h>
 
 
 
 
  48
  49#include <linux/proc_fs.h>
  50#include <linux/seq_file.h>
 
  51#include "udp_impl.h"
  52
  53int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
  54{
  55	const struct in6_addr *sk_rcv_saddr6 = &inet6_sk(sk)->rcv_saddr;
  56	const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
  57	__be32 sk1_rcv_saddr = sk_rcv_saddr(sk);
  58	__be32 sk2_rcv_saddr = sk_rcv_saddr(sk2);
  59	int sk_ipv6only = ipv6_only_sock(sk);
  60	int sk2_ipv6only = inet_v6_ipv6only(sk2);
  61	int addr_type = ipv6_addr_type(sk_rcv_saddr6);
  62	int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
  63
  64	/* if both are mapped, treat as IPv4 */
  65	if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED)
  66		return (!sk2_ipv6only &&
  67			(!sk1_rcv_saddr || !sk2_rcv_saddr ||
  68			  sk1_rcv_saddr == sk2_rcv_saddr));
  69
  70	if (addr_type2 == IPV6_ADDR_ANY &&
  71	    !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
  72		return 1;
  73
  74	if (addr_type == IPV6_ADDR_ANY &&
  75	    !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED))
  76		return 1;
  77
  78	if (sk2_rcv_saddr6 &&
  79	    ipv6_addr_equal(sk_rcv_saddr6, sk2_rcv_saddr6))
  80		return 1;
  81
 
 
 
 
 
  82	return 0;
  83}
  84
  85static unsigned int udp6_portaddr_hash(struct net *net,
  86				       const struct in6_addr *addr6,
  87				       unsigned int port)
  88{
  89	unsigned int hash, mix = net_hash_mix(net);
  90
  91	if (ipv6_addr_any(addr6))
  92		hash = jhash_1word(0, mix);
  93	else if (ipv6_addr_v4mapped(addr6))
  94		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
  95	else
  96		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
 
 
 
  97
  98	return hash ^ port;
  99}
 100
 
 
 
 101
 102int udp_v6_get_port(struct sock *sk, unsigned short snum)
 103{
 104	unsigned int hash2_nulladdr =
 105		udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
 106	unsigned int hash2_partial = 
 107		udp6_portaddr_hash(sock_net(sk), &inet6_sk(sk)->rcv_saddr, 0);
 108
 109	/* precompute partial secondary hash */
 110	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
 111	return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
 112}
 113
 114static void udp_v6_rehash(struct sock *sk)
 115{
 116	u16 new_hash = udp6_portaddr_hash(sock_net(sk),
 117					  &inet6_sk(sk)->rcv_saddr,
 118					  inet_sk(sk)->inet_num);
 119
 120	udp_lib_rehash(sk, new_hash);
 121}
 122
 123static inline int compute_score(struct sock *sk, struct net *net,
 124				unsigned short hnum,
 125				const struct in6_addr *saddr, __be16 sport,
 126				const struct in6_addr *daddr, __be16 dport,
 127				int dif)
 128{
 129	int score = -1;
 130
 131	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
 132			sk->sk_family == PF_INET6) {
 133		struct ipv6_pinfo *np = inet6_sk(sk);
 134		struct inet_sock *inet = inet_sk(sk);
 135
 136		score = 0;
 137		if (inet->inet_dport) {
 138			if (inet->inet_dport != sport)
 139				return -1;
 140			score++;
 141		}
 142		if (!ipv6_addr_any(&np->rcv_saddr)) {
 143			if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
 144				return -1;
 145			score++;
 146		}
 147		if (!ipv6_addr_any(&np->daddr)) {
 148			if (!ipv6_addr_equal(&np->daddr, saddr))
 149				return -1;
 150			score++;
 151		}
 152		if (sk->sk_bound_dev_if) {
 153			if (sk->sk_bound_dev_if != dif)
 154				return -1;
 155			score++;
 156		}
 157	}
 158	return score;
 159}
 160
 161#define SCORE2_MAX (1 + 1 + 1)
 162static inline int compute_score2(struct sock *sk, struct net *net,
 163				const struct in6_addr *saddr, __be16 sport,
 164				const struct in6_addr *daddr, unsigned short hnum,
 165				int dif)
 166{
 167	int score = -1;
 168
 169	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
 170			sk->sk_family == PF_INET6) {
 171		struct ipv6_pinfo *np = inet6_sk(sk);
 172		struct inet_sock *inet = inet_sk(sk);
 173
 174		if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
 
 
 
 
 175			return -1;
 176		score = 0;
 177		if (inet->inet_dport) {
 178			if (inet->inet_dport != sport)
 179				return -1;
 180			score++;
 181		}
 182		if (!ipv6_addr_any(&np->daddr)) {
 183			if (!ipv6_addr_equal(&np->daddr, saddr))
 184				return -1;
 185			score++;
 186		}
 187		if (sk->sk_bound_dev_if) {
 188			if (sk->sk_bound_dev_if != dif)
 189				return -1;
 190			score++;
 191		}
 192	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 193	return score;
 194}
 195
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 196
 197/* called with read_rcu_lock() */
 198static struct sock *udp6_lib_lookup2(struct net *net,
 199		const struct in6_addr *saddr, __be16 sport,
 200		const struct in6_addr *daddr, unsigned int hnum, int dif,
 201		struct udp_hslot *hslot2, unsigned int slot2)
 
 202{
 203	struct sock *sk, *result;
 204	struct hlist_nulls_node *node;
 205	int score, badness;
 206
 207begin:
 208	result = NULL;
 209	badness = -1;
 210	udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
 211		score = compute_score2(sk, net, saddr, sport,
 212				      daddr, hnum, dif);
 213		if (score > badness) {
 214			result = sk;
 215			badness = score;
 216			if (score == SCORE2_MAX)
 217				goto exact_match;
 218		}
 219	}
 220	/*
 221	 * if the nulls value we got at the end of this lookup is
 222	 * not the expected one, we must restart lookup.
 223	 * We probably met an item that was moved to another chain.
 224	 */
 225	if (get_nulls_value(node) != slot2)
 226		goto begin;
 227
 228	if (result) {
 229exact_match:
 230		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 231			result = NULL;
 232		else if (unlikely(compute_score2(result, net, saddr, sport,
 233				  daddr, hnum, dif) < badness)) {
 234			sock_put(result);
 235			goto begin;
 236		}
 237	}
 238	return result;
 239}
 240
 241static struct sock *__udp6_lib_lookup(struct net *net,
 242				      const struct in6_addr *saddr, __be16 sport,
 243				      const struct in6_addr *daddr, __be16 dport,
 244				      int dif, struct udp_table *udptable)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 245{
 246	struct sock *sk, *result;
 247	struct hlist_nulls_node *node;
 248	unsigned short hnum = ntohs(dport);
 249	unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
 250	struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
 251	int score, badness;
 252
 253	rcu_read_lock();
 254	if (hslot->count > 10) {
 255		hash2 = udp6_portaddr_hash(net, daddr, hnum);
 256		slot2 = hash2 & udptable->mask;
 257		hslot2 = &udptable->hash2[slot2];
 258		if (hslot->count < hslot2->count)
 259			goto begin;
 260
 261		result = udp6_lib_lookup2(net, saddr, sport,
 262					  daddr, hnum, dif,
 263					  hslot2, slot2);
 264		if (!result) {
 265			hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
 266			slot2 = hash2 & udptable->mask;
 267			hslot2 = &udptable->hash2[slot2];
 268			if (hslot->count < hslot2->count)
 269				goto begin;
 270
 271			result = udp6_lib_lookup2(net, saddr, sport,
 272						  &in6addr_any, hnum, dif,
 273						  hslot2, slot2);
 274		}
 275		rcu_read_unlock();
 276		return result;
 277	}
 278begin:
 279	result = NULL;
 280	badness = -1;
 281	sk_nulls_for_each_rcu(sk, node, &hslot->head) {
 282		score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
 283		if (score > badness) {
 284			result = sk;
 285			badness = score;
 286		}
 287	}
 288	/*
 289	 * if the nulls value we got at the end of this lookup is
 290	 * not the expected one, we must restart lookup.
 291	 * We probably met an item that was moved to another chain.
 292	 */
 293	if (get_nulls_value(node) != slot)
 294		goto begin;
 295
 296	if (result) {
 297		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 298			result = NULL;
 299		else if (unlikely(compute_score(result, net, hnum, saddr, sport,
 300					daddr, dport, dif) < badness)) {
 301			sock_put(result);
 302			goto begin;
 303		}
 304	}
 305	rcu_read_unlock();
 
 
 
 
 
 306	return result;
 307}
 
 308
 309static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 310					  __be16 sport, __be16 dport,
 311					  struct udp_table *udptable)
 312{
 313	struct sock *sk;
 314	const struct ipv6hdr *iph = ipv6_hdr(skb);
 315
 316	if (unlikely(sk = skb_steal_sock(skb)))
 317		return sk;
 318	return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
 319				 &iph->daddr, dport, inet6_iif(skb),
 320				 udptable);
 321}
 322
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 323struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 324			     const struct in6_addr *daddr, __be16 dport, int dif)
 325{
 326	return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
 
 
 
 
 
 
 327}
 328EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 
 329
 
 
 
 
 
 
 
 
 330
 331/*
 332 * 	This should be easy, if there is something there we
 333 * 	return it, otherwise we block.
 334 */
 335
 336int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 337		  struct msghdr *msg, size_t len,
 338		  int noblock, int flags, int *addr_len)
 339{
 340	struct ipv6_pinfo *np = inet6_sk(sk);
 341	struct inet_sock *inet = inet_sk(sk);
 342	struct sk_buff *skb;
 343	unsigned int ulen;
 344	int peeked;
 345	int err;
 346	int is_udplite = IS_UDPLITE(sk);
 
 
 347	int is_udp4;
 348	bool slow;
 349
 350	if (addr_len)
 351		*addr_len=sizeof(struct sockaddr_in6);
 352
 353	if (flags & MSG_ERRQUEUE)
 354		return ipv6_recv_error(sk, msg, len);
 355
 356	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 357		return ipv6_recv_rxpmtu(sk, msg, len);
 358
 359try_again:
 360	skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
 361				  &peeked, &err);
 362	if (!skb)
 363		goto out;
 364
 365	ulen = skb->len - sizeof(struct udphdr);
 366	if (len > ulen)
 367		len = ulen;
 368	else if (len < ulen)
 
 369		msg->msg_flags |= MSG_TRUNC;
 370
 371	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 
 372
 373	/*
 374	 * If checksum is needed at all, try to do it while copying the
 375	 * data.  If the data is truncated, or if we only want a partial
 376	 * coverage checksum (UDP-Lite), do it before the copy.
 377	 */
 378
 379	if (len < ulen || UDP_SKB_CB(skb)->partial_cov) {
 380		if (udp_lib_checksum_complete(skb))
 
 
 
 381			goto csum_copy_err;
 382	}
 383
 384	if (skb_csum_unnecessary(skb))
 385		err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
 386					      msg->msg_iov,len);
 387	else {
 388		err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 
 
 389		if (err == -EINVAL)
 390			goto csum_copy_err;
 391	}
 392	if (err)
 393		goto out_free;
 394
 395	if (!peeked) {
 396		if (is_udp4)
 397			UDP_INC_STATS_USER(sock_net(sk),
 398					UDP_MIB_INDATAGRAMS, is_udplite);
 399		else
 400			UDP6_INC_STATS_USER(sock_net(sk),
 401					UDP_MIB_INDATAGRAMS, is_udplite);
 402	}
 
 
 403
 404	sock_recv_ts_and_drops(msg, sk, skb);
 405
 406	/* Copy the address. */
 407	if (msg->msg_name) {
 408		struct sockaddr_in6 *sin6;
 409
 410		sin6 = (struct sockaddr_in6 *) msg->msg_name;
 411		sin6->sin6_family = AF_INET6;
 412		sin6->sin6_port = udp_hdr(skb)->source;
 413		sin6->sin6_flowinfo = 0;
 414		sin6->sin6_scope_id = 0;
 415
 416		if (is_udp4)
 417			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 418					       &sin6->sin6_addr);
 419		else {
 420			ipv6_addr_copy(&sin6->sin6_addr,
 421				       &ipv6_hdr(skb)->saddr);
 422			if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 423				sin6->sin6_scope_id = IP6CB(skb)->iif;
 
 424		}
 
 425
 
 
 426	}
 
 
 
 
 
 
 
 427	if (is_udp4) {
 428		if (inet->cmsg_flags)
 429			ip_cmsg_recv(msg, skb);
 
 430	} else {
 431		if (np->rxopt.all)
 432			datagram_recv_ctl(sk, msg, skb);
 433	}
 434
 435	err = len;
 436	if (flags & MSG_TRUNC)
 437		err = ulen;
 438
 439out_free:
 440	skb_free_datagram_locked(sk, skb);
 441out:
 442	return err;
 443
 444csum_copy_err:
 445	slow = lock_sock_fast(sk);
 446	if (!skb_kill_datagram(sk, skb, flags)) {
 447		if (is_udp4)
 448			UDP_INC_STATS_USER(sock_net(sk),
 449					UDP_MIB_INERRORS, is_udplite);
 450		else
 451			UDP6_INC_STATS_USER(sock_net(sk),
 452					UDP_MIB_INERRORS, is_udplite);
 453	}
 454	unlock_sock_fast(sk, slow);
 455
 456	if (noblock)
 457		return -EAGAIN;
 458
 459	/* starting over for a new packet */
 
 460	msg->msg_flags &= ~MSG_TRUNC;
 461	goto try_again;
 462}
 463
 464void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 465		    u8 type, u8 code, int offset, __be32 info,
 466		    struct udp_table *udptable)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 467{
 468	struct ipv6_pinfo *np;
 469	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 470	const struct in6_addr *saddr = &hdr->saddr;
 471	const struct in6_addr *daddr = &hdr->daddr;
 472	struct udphdr *uh = (struct udphdr*)(skb->data+offset);
 
 473	struct sock *sk;
 
 474	int err;
 
 475
 476	sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
 477			       saddr, uh->source, inet6_iif(skb), udptable);
 478	if (sk == NULL)
 479		return;
 480
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 481	np = inet6_sk(sk);
 482
 483	if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
 
 
 
 
 
 
 
 
 
 
 
 
 
 484		goto out;
 
 485
 486	if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
 
 
 
 
 487		goto out;
 
 488
 489	if (np->recverr)
 
 
 
 490		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 
 491
 492	sk->sk_err = err;
 493	sk->sk_error_report(sk);
 494out:
 495	sock_put(sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 496}
 497
 498static __inline__ void udpv6_err(struct sk_buff *skb,
 499				 struct inet6_skb_parm *opt, u8 type,
 500				 u8 code, int offset, __be32 info     )
 501{
 502	__udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 
 503}
 504
 505int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
 506{
 
 507	struct udp_sock *up = udp_sk(sk);
 508	int rc;
 509	int is_udplite = IS_UDPLITE(sk);
 510
 511	if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
 512		sock_rps_save_rxhash(sk, skb->rxhash);
 513
 514	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 515		goto drop;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 516
 517	/*
 518	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 519	 */
 520	if ((is_udplite & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 521
 522		if (up->pcrlen == 0) {          /* full coverage was set  */
 523			LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
 524				" %d while full coverage %d requested\n",
 525				UDP_SKB_CB(skb)->cscov, skb->len);
 526			goto drop;
 527		}
 528		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 529			LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
 530						    "too small, need min %d\n",
 531				       UDP_SKB_CB(skb)->cscov, up->pcrlen);
 532			goto drop;
 533		}
 534	}
 535
 536	if (rcu_dereference_raw(sk->sk_filter)) {
 537		if (udp_lib_checksum_complete(skb))
 538			goto drop;
 539	}
 540
 541	if ((rc = ip_queue_rcv_skb(sk, skb)) < 0) {
 542		/* Note that an ENOMEM error is charged twice */
 543		if (rc == -ENOMEM)
 544			UDP6_INC_STATS_BH(sock_net(sk),
 545					UDP_MIB_RCVBUFERRORS, is_udplite);
 546		goto drop_no_sk_drops_inc;
 547	}
 548
 549	return 0;
 
 
 
 
 
 
 
 
 550drop:
 
 551	atomic_inc(&sk->sk_drops);
 552drop_no_sk_drops_inc:
 553	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 554	kfree_skb(skb);
 555	return -1;
 556}
 557
 558static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
 559				      __be16 loc_port, const struct in6_addr *loc_addr,
 560				      __be16 rmt_port, const struct in6_addr *rmt_addr,
 561				      int dif)
 562{
 563	struct hlist_nulls_node *node;
 564	struct sock *s = sk;
 565	unsigned short num = ntohs(loc_port);
 566
 567	sk_nulls_for_each_from(s, node) {
 568		struct inet_sock *inet = inet_sk(s);
 569
 570		if (!net_eq(sock_net(s), net))
 571			continue;
 572
 573		if (udp_sk(s)->udp_port_hash == num &&
 574		    s->sk_family == PF_INET6) {
 575			struct ipv6_pinfo *np = inet6_sk(s);
 576			if (inet->inet_dport) {
 577				if (inet->inet_dport != rmt_port)
 578					continue;
 579			}
 580			if (!ipv6_addr_any(&np->daddr) &&
 581			    !ipv6_addr_equal(&np->daddr, rmt_addr))
 582				continue;
 583
 584			if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 585				continue;
 586
 587			if (!ipv6_addr_any(&np->rcv_saddr)) {
 588				if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
 589					continue;
 590			}
 591			if (!inet6_mc_check(s, loc_addr, rmt_addr))
 592				continue;
 593			return s;
 594		}
 595	}
 596	return NULL;
 597}
 598
 599static void flush_stack(struct sock **stack, unsigned int count,
 600			struct sk_buff *skb, unsigned int final)
 
 
 601{
 602	unsigned int i;
 603	struct sock *sk;
 604	struct sk_buff *skb1;
 605
 606	for (i = 0; i < count; i++) {
 607		skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
 608
 609		sk = stack[i];
 610		if (skb1) {
 611			if (sk_rcvqueues_full(sk, skb1)) {
 612				kfree_skb(skb1);
 613				goto drop;
 614			}
 615			bh_lock_sock(sk);
 616			if (!sock_owned_by_user(sk))
 617				udpv6_queue_rcv_skb(sk, skb1);
 618			else if (sk_add_backlog(sk, skb1)) {
 619				kfree_skb(skb1);
 620				bh_unlock_sock(sk);
 621				goto drop;
 622			}
 623			bh_unlock_sock(sk);
 624			continue;
 625		}
 626drop:
 627		atomic_inc(&sk->sk_drops);
 628		UDP6_INC_STATS_BH(sock_net(sk),
 629				UDP_MIB_RCVBUFERRORS, IS_UDPLITE(sk));
 630		UDP6_INC_STATS_BH(sock_net(sk),
 631				UDP_MIB_INERRORS, IS_UDPLITE(sk));
 632	}
 633}
 
 634/*
 635 * Note: called only from the BH handler context,
 636 * so we don't need to lock the hashes.
 637 */
 638static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 639		const struct in6_addr *saddr, const struct in6_addr *daddr,
 640		struct udp_table *udptable)
 641{
 642	struct sock *sk, *stack[256 / sizeof(struct sock *)];
 643	const struct udphdr *uh = udp_hdr(skb);
 644	struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
 645	int dif;
 646	unsigned int i, count = 0;
 647
 648	spin_lock(&hslot->lock);
 649	sk = sk_nulls_head(&hslot->head);
 650	dif = inet6_iif(skb);
 651	sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
 652	while (sk) {
 653		stack[count++] = sk;
 654		sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
 655				       uh->source, saddr, dif);
 656		if (unlikely(count == ARRAY_SIZE(stack))) {
 657			if (!sk)
 658				break;
 659			flush_stack(stack, count, skb, ~0);
 660			count = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 661		}
 662	}
 663	/*
 664	 * before releasing the lock, we must take reference on sockets
 665	 */
 666	for (i = 0; i < count; i++)
 667		sock_hold(stack[i]);
 668
 669	spin_unlock(&hslot->lock);
 
 
 670
 671	if (count) {
 672		flush_stack(stack, count, skb, count - 1);
 
 
 
 673
 674		for (i = 0; i < count; i++)
 675			sock_put(stack[i]);
 
 676	} else {
 677		kfree_skb(skb);
 
 
 678	}
 679	return 0;
 680}
 681
 682static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh,
 683				 int proto)
 684{
 685	int err;
 686
 687	UDP_SKB_CB(skb)->partial_cov = 0;
 688	UDP_SKB_CB(skb)->cscov = skb->len;
 689
 690	if (proto == IPPROTO_UDPLITE) {
 691		err = udplite_checksum_init(skb, uh);
 692		if (err)
 693			return err;
 694	}
 
 695
 696	if (uh->check == 0) {
 697		/* RFC 2460 section 8.1 says that we SHOULD log
 698		   this error. Well, it is reasonable.
 699		 */
 700		LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
 701		return 1;
 702	}
 703	if (skb->ip_summed == CHECKSUM_COMPLETE &&
 704	    !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
 705			     skb->len, proto, skb->csum))
 706		skb->ip_summed = CHECKSUM_UNNECESSARY;
 707
 708	if (!skb_csum_unnecessary(skb))
 709		skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
 710							 &ipv6_hdr(skb)->daddr,
 711							 skb->len, proto, 0));
 712
 
 
 
 
 
 713	return 0;
 714}
 715
 716int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 717		   int proto)
 718{
 
 
 719	struct net *net = dev_net(skb->dev);
 720	struct sock *sk;
 721	struct udphdr *uh;
 722	const struct in6_addr *saddr, *daddr;
 
 723	u32 ulen = 0;
 724
 725	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 726		goto discard;
 727
 728	saddr = &ipv6_hdr(skb)->saddr;
 729	daddr = &ipv6_hdr(skb)->daddr;
 730	uh = udp_hdr(skb);
 731
 732	ulen = ntohs(uh->len);
 733	if (ulen > skb->len)
 734		goto short_packet;
 735
 736	if (proto == IPPROTO_UDP) {
 737		/* UDP validates ulen. */
 738
 739		/* Check for jumbo payload */
 740		if (ulen == 0)
 741			ulen = skb->len;
 742
 743		if (ulen < sizeof(*uh))
 744			goto short_packet;
 745
 746		if (ulen < skb->len) {
 747			if (pskb_trim_rcsum(skb, ulen))
 748				goto short_packet;
 749			saddr = &ipv6_hdr(skb)->saddr;
 750			daddr = &ipv6_hdr(skb)->daddr;
 751			uh = udp_hdr(skb);
 752		}
 753	}
 754
 755	if (udp6_csum_init(skb, uh, proto))
 756		goto discard;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 757
 758	/*
 759	 *	Multicast receive code
 760	 */
 761	if (ipv6_addr_is_multicast(daddr))
 762		return __udp6_lib_mcast_deliver(net, skb,
 763				saddr, daddr, udptable);
 764
 765	/* Unicast */
 766
 767	/*
 768	 * check socket cache ... must talk to Alan about his plans
 769	 * for sock caches... i'll skip this for now.
 770	 */
 771	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
 
 
 
 
 
 772
 773	if (sk == NULL) {
 774		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 775			goto discard;
 776
 777		if (udp_lib_checksum_complete(skb))
 778			goto discard;
 779		UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS,
 780				proto == IPPROTO_UDPLITE);
 781
 782		icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 
 783
 784		kfree_skb(skb);
 785		return 0;
 786	}
 787
 788	/* deliver */
 
 789
 790	if (sk_rcvqueues_full(sk, skb)) {
 791		sock_put(sk);
 792		goto discard;
 793	}
 794	bh_lock_sock(sk);
 795	if (!sock_owned_by_user(sk))
 796		udpv6_queue_rcv_skb(sk, skb);
 797	else if (sk_add_backlog(sk, skb)) {
 798		atomic_inc(&sk->sk_drops);
 799		bh_unlock_sock(sk);
 800		sock_put(sk);
 801		goto discard;
 802	}
 803	bh_unlock_sock(sk);
 804	sock_put(sk);
 805	return 0;
 806
 807short_packet:
 808	LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
 809		       proto == IPPROTO_UDPLITE ? "-Lite" : "",
 810		       saddr,
 811		       ntohs(uh->source),
 812		       ulen,
 813		       skb->len,
 814		       daddr,
 815		       ntohs(uh->dest));
 816
 
 
 
 
 
 
 817discard:
 818	UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
 819	kfree_skb(skb);
 820	return 0;
 821}
 822
 823static __inline__ int udpv6_rcv(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 824{
 825	return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 826}
 827
 828/*
 829 * Throw away all pending data and cancel the corking. Socket is locked.
 830 */
 831static void udp_v6_flush_pending_frames(struct sock *sk)
 832{
 833	struct udp_sock *up = udp_sk(sk);
 834
 835	if (up->pending == AF_INET)
 836		udp_flush_pending_frames(sk);
 837	else if (up->pending) {
 838		up->len = 0;
 839		up->pending = 0;
 840		ip6_flush_pending_frames(sk);
 841	}
 842}
 843
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 844/**
 845 * 	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
 846 * 	@sk: 	socket we are sending on
 847 * 	@skb: 	sk_buff containing the filled-in UDP header
 848 * 	        (checksum field must be zeroed out)
 
 
 
 849 */
 850static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
 851				 const struct in6_addr *saddr,
 852				 const struct in6_addr *daddr, int len)
 853{
 854	unsigned int offset;
 855	struct udphdr *uh = udp_hdr(skb);
 
 856	__wsum csum = 0;
 857
 858	if (skb_queue_len(&sk->sk_write_queue) == 1) {
 859		/* Only one fragment on the socket.  */
 860		skb->csum_start = skb_transport_header(skb) - skb->head;
 861		skb->csum_offset = offsetof(struct udphdr, check);
 862		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
 863	} else {
 864		/*
 865		 * HW-checksum won't work as there are two or more
 866		 * fragments on the socket so that all csums of sk_buffs
 867		 * should be together
 868		 */
 869		offset = skb_transport_offset(skb);
 870		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
 
 871
 872		skb->ip_summed = CHECKSUM_NONE;
 873
 874		skb_queue_walk(&sk->sk_write_queue, skb) {
 875			csum = csum_add(csum, skb->csum);
 876		}
 877
 878		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
 879					    csum);
 880		if (uh->check == 0)
 881			uh->check = CSUM_MANGLED_0;
 882	}
 883}
 884
 885/*
 886 *	Sending
 887 */
 888
 889static int udp_v6_push_pending_frames(struct sock *sk)
 
 890{
 891	struct sk_buff *skb;
 892	struct udphdr *uh;
 893	struct udp_sock  *up = udp_sk(sk);
 894	struct inet_sock *inet = inet_sk(sk);
 895	struct flowi6 *fl6 = &inet->cork.fl.u.ip6;
 896	int err = 0;
 897	int is_udplite = IS_UDPLITE(sk);
 898	__wsum csum = 0;
 899
 900	/* Grab the skbuff where UDP header space exists. */
 901	if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 902		goto out;
 903
 904	/*
 905	 * Create a UDP header
 906	 */
 907	uh = udp_hdr(skb);
 908	uh->source = fl6->fl6_sport;
 909	uh->dest = fl6->fl6_dport;
 910	uh->len = htons(up->len);
 911	uh->check = 0;
 912
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 913	if (is_udplite)
 914		csum = udplite_csum_outgoing(sk, skb);
 915	else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
 916		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
 917				     up->len);
 
 
 
 918		goto send;
 919	} else
 920		csum = udp_csum_outgoing(sk, skb);
 921
 922	/* add protocol-dependent pseudo-header */
 923	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
 924				    up->len, fl6->flowi6_proto, csum);
 925	if (uh->check == 0)
 926		uh->check = CSUM_MANGLED_0;
 927
 928send:
 929	err = ip6_push_pending_frames(sk);
 930	if (err) {
 931		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
 932			UDP6_INC_STATS_USER(sock_net(sk),
 933					    UDP_MIB_SNDBUFERRORS, is_udplite);
 934			err = 0;
 935		}
 936	} else
 937		UDP6_INC_STATS_USER(sock_net(sk),
 938				    UDP_MIB_OUTDATAGRAMS, is_udplite);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 939out:
 940	up->len = 0;
 941	up->pending = 0;
 942	return err;
 943}
 944
 945int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 946		  struct msghdr *msg, size_t len)
 947{
 948	struct ipv6_txoptions opt_space;
 949	struct udp_sock *up = udp_sk(sk);
 950	struct inet_sock *inet = inet_sk(sk);
 951	struct ipv6_pinfo *np = inet6_sk(sk);
 952	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
 953	struct in6_addr *daddr, *final_p, final;
 954	struct ipv6_txoptions *opt = NULL;
 
 955	struct ip6_flowlabel *flowlabel = NULL;
 956	struct flowi6 fl6;
 
 957	struct dst_entry *dst;
 
 958	int addr_len = msg->msg_namelen;
 
 959	int ulen = len;
 960	int hlimit = -1;
 961	int tclass = -1;
 962	int dontfrag = -1;
 963	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
 964	int err;
 965	int connected = 0;
 966	int is_udplite = IS_UDPLITE(sk);
 967	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
 968
 
 
 
 
 
 969	/* destination address check */
 970	if (sin6) {
 971		if (addr_len < offsetof(struct sockaddr, sa_data))
 972			return -EINVAL;
 973
 974		switch (sin6->sin6_family) {
 975		case AF_INET6:
 976			if (addr_len < SIN6_LEN_RFC2133)
 977				return -EINVAL;
 978			daddr = &sin6->sin6_addr;
 
 
 
 
 979			break;
 980		case AF_INET:
 981			goto do_udp_sendmsg;
 982		case AF_UNSPEC:
 983			msg->msg_name = sin6 = NULL;
 984			msg->msg_namelen = addr_len = 0;
 985			daddr = NULL;
 986			break;
 987		default:
 988			return -EINVAL;
 989		}
 990	} else if (!up->pending) {
 991		if (sk->sk_state != TCP_ESTABLISHED)
 992			return -EDESTADDRREQ;
 993		daddr = &np->daddr;
 994	} else
 995		daddr = NULL;
 996
 997	if (daddr) {
 998		if (ipv6_addr_v4mapped(daddr)) {
 999			struct sockaddr_in sin;
1000			sin.sin_family = AF_INET;
1001			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1002			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1003			msg->msg_name = &sin;
1004			msg->msg_namelen = sizeof(sin);
1005do_udp_sendmsg:
1006			if (__ipv6_only_sock(sk))
1007				return -ENETUNREACH;
1008			return udp_sendmsg(iocb, sk, msg, len);
1009		}
1010	}
1011
1012	if (up->pending == AF_INET)
1013		return udp_sendmsg(iocb, sk, msg, len);
1014
1015	/* Rough check on arithmetic overflow,
1016	   better check is made in ip6_append_data().
1017	   */
1018	if (len > INT_MAX - sizeof(struct udphdr))
1019		return -EMSGSIZE;
1020
 
1021	if (up->pending) {
 
 
1022		/*
1023		 * There are pending frames.
1024		 * The socket lock must be held while it's corked.
1025		 */
1026		lock_sock(sk);
1027		if (likely(up->pending)) {
1028			if (unlikely(up->pending != AF_INET6)) {
1029				release_sock(sk);
1030				return -EAFNOSUPPORT;
1031			}
1032			dst = NULL;
1033			goto do_append_data;
1034		}
1035		release_sock(sk);
1036	}
1037	ulen += sizeof(struct udphdr);
1038
1039	memset(&fl6, 0, sizeof(fl6));
1040
1041	if (sin6) {
1042		if (sin6->sin6_port == 0)
1043			return -EINVAL;
1044
1045		fl6.fl6_dport = sin6->sin6_port;
1046		daddr = &sin6->sin6_addr;
1047
1048		if (np->sndflow) {
1049			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1050			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1051				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1052				if (flowlabel == NULL)
1053					return -EINVAL;
1054				daddr = &flowlabel->dst;
1055			}
1056		}
1057
1058		/*
1059		 * Otherwise it will be difficult to maintain
1060		 * sk->sk_dst_cache.
1061		 */
1062		if (sk->sk_state == TCP_ESTABLISHED &&
1063		    ipv6_addr_equal(daddr, &np->daddr))
1064			daddr = &np->daddr;
1065
1066		if (addr_len >= sizeof(struct sockaddr_in6) &&
1067		    sin6->sin6_scope_id &&
1068		    ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
1069			fl6.flowi6_oif = sin6->sin6_scope_id;
1070	} else {
1071		if (sk->sk_state != TCP_ESTABLISHED)
1072			return -EDESTADDRREQ;
1073
1074		fl6.fl6_dport = inet->inet_dport;
1075		daddr = &np->daddr;
1076		fl6.flowlabel = np->flow_label;
1077		connected = 1;
1078	}
1079
1080	if (!fl6.flowi6_oif)
1081		fl6.flowi6_oif = sk->sk_bound_dev_if;
1082
1083	if (!fl6.flowi6_oif)
1084		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1085
1086	fl6.flowi6_mark = sk->sk_mark;
1087
1088	if (msg->msg_controllen) {
1089		opt = &opt_space;
1090		memset(opt, 0, sizeof(struct ipv6_txoptions));
1091		opt->tot_len = sizeof(*opt);
 
1092
1093		err = datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1094					&hlimit, &tclass, &dontfrag);
 
 
1095		if (err < 0) {
1096			fl6_sock_release(flowlabel);
1097			return err;
1098		}
1099		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1100			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1101			if (flowlabel == NULL)
1102				return -EINVAL;
1103		}
1104		if (!(opt->opt_nflen|opt->opt_flen))
1105			opt = NULL;
1106		connected = 0;
 
 
 
 
1107	}
1108	if (opt == NULL)
1109		opt = np->opt;
1110	if (flowlabel)
1111		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1112	opt = ipv6_fixup_options(&opt_space, opt);
 
1113
1114	fl6.flowi6_proto = sk->sk_protocol;
1115	if (!ipv6_addr_any(daddr))
1116		ipv6_addr_copy(&fl6.daddr, daddr);
1117	else
1118		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1119	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1120		ipv6_addr_copy(&fl6.saddr, &np->saddr);
1121	fl6.fl6_sport = inet->inet_sport;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1122
1123	final_p = fl6_update_dst(&fl6, opt, &final);
1124	if (final_p)
1125		connected = 0;
1126
1127	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1128		fl6.flowi6_oif = np->mcast_oif;
1129		connected = 0;
1130	}
 
1131
1132	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1133
1134	dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, true);
 
 
 
 
 
1135	if (IS_ERR(dst)) {
1136		err = PTR_ERR(dst);
1137		dst = NULL;
1138		goto out;
1139	}
1140
1141	if (hlimit < 0) {
1142		if (ipv6_addr_is_multicast(&fl6.daddr))
1143			hlimit = np->mcast_hops;
1144		else
1145			hlimit = np->hop_limit;
1146		if (hlimit < 0)
1147			hlimit = ip6_dst_hoplimit(dst);
1148	}
1149
1150	if (tclass < 0)
1151		tclass = np->tclass;
1152
1153	if (dontfrag < 0)
1154		dontfrag = np->dontfrag;
1155
1156	if (msg->msg_flags&MSG_CONFIRM)
1157		goto do_confirm;
1158back_from_confirm:
1159
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1160	lock_sock(sk);
1161	if (unlikely(up->pending)) {
1162		/* The socket is already corked while preparing it. */
1163		/* ... which is an evident application bug. --ANK */
1164		release_sock(sk);
1165
1166		LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1167		err = -EINVAL;
1168		goto out;
1169	}
1170
1171	up->pending = AF_INET6;
1172
1173do_append_data:
 
 
1174	up->len += ulen;
1175	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1176	err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1177		sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1178		(struct rt6_info*)dst,
1179		corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1180	if (err)
1181		udp_v6_flush_pending_frames(sk);
1182	else if (!corkreq)
1183		err = udp_v6_push_pending_frames(sk);
1184	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1185		up->pending = 0;
1186
1187	if (dst) {
1188		if (connected) {
1189			ip6_dst_store(sk, dst,
1190				      ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
1191				      &np->daddr : NULL,
1192#ifdef CONFIG_IPV6_SUBTREES
1193				      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1194				      &np->saddr :
1195#endif
1196				      NULL);
1197		} else {
1198			dst_release(dst);
1199		}
1200		dst = NULL;
1201	}
1202
1203	if (err > 0)
1204		err = np->recverr ? net_xmit_errno(err) : 0;
1205	release_sock(sk);
 
1206out:
1207	dst_release(dst);
 
1208	fl6_sock_release(flowlabel);
 
1209	if (!err)
1210		return len;
1211	/*
1212	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1213	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1214	 * we don't have a good statistic (IpOutDiscards but it can be too many
1215	 * things).  We could add another new stat but at least for now that
1216	 * seems like overkill.
1217	 */
1218	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1219		UDP6_INC_STATS_USER(sock_net(sk),
1220				UDP_MIB_SNDBUFERRORS, is_udplite);
1221	}
1222	return err;
1223
1224do_confirm:
1225	dst_confirm(dst);
 
1226	if (!(msg->msg_flags&MSG_PROBE) || len)
1227		goto back_from_confirm;
1228	err = 0;
1229	goto out;
1230}
 
1231
1232void udpv6_destroy_sock(struct sock *sk)
1233{
 
1234	lock_sock(sk);
 
 
 
1235	udp_v6_flush_pending_frames(sk);
1236	release_sock(sk);
1237
1238	inet6_destroy_sock(sk);
 
 
 
 
 
 
 
 
 
 
 
1239}
1240
1241/*
1242 *	Socket option code for UDP
1243 */
1244int udpv6_setsockopt(struct sock *sk, int level, int optname,
1245		     char __user *optval, unsigned int optlen)
1246{
1247	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1248		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
 
1249					  udp_v6_push_pending_frames);
1250	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1251}
1252
1253#ifdef CONFIG_COMPAT
1254int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1255			    char __user *optval, unsigned int optlen)
1256{
1257	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1258		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1259					  udp_v6_push_pending_frames);
1260	return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1261}
1262#endif
1263
1264int udpv6_getsockopt(struct sock *sk, int level, int optname,
1265		     char __user *optval, int __user *optlen)
1266{
1267	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1268		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1269	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1270}
1271
1272#ifdef CONFIG_COMPAT
1273int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1274			    char __user *optval, int __user *optlen)
1275{
1276	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1277		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1278	return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1279}
1280#endif
1281
1282static int udp6_ufo_send_check(struct sk_buff *skb)
1283{
1284	const struct ipv6hdr *ipv6h;
1285	struct udphdr *uh;
1286
1287	if (!pskb_may_pull(skb, sizeof(*uh)))
1288		return -EINVAL;
1289
1290	ipv6h = ipv6_hdr(skb);
1291	uh = udp_hdr(skb);
1292
1293	uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
1294				     IPPROTO_UDP, 0);
1295	skb->csum_start = skb_transport_header(skb) - skb->head;
1296	skb->csum_offset = offsetof(struct udphdr, check);
1297	skb->ip_summed = CHECKSUM_PARTIAL;
1298	return 0;
1299}
1300
1301static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, u32 features)
1302{
1303	struct sk_buff *segs = ERR_PTR(-EINVAL);
1304	unsigned int mss;
1305	unsigned int unfrag_ip6hlen, unfrag_len;
1306	struct frag_hdr *fptr;
1307	u8 *mac_start, *prevhdr;
1308	u8 nexthdr;
1309	u8 frag_hdr_sz = sizeof(struct frag_hdr);
1310	int offset;
1311	__wsum csum;
1312
1313	mss = skb_shinfo(skb)->gso_size;
1314	if (unlikely(skb->len <= mss))
1315		goto out;
1316
1317	if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
1318		/* Packet is from an untrusted source, reset gso_segs. */
1319		int type = skb_shinfo(skb)->gso_type;
1320
1321		if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
1322			     !(type & (SKB_GSO_UDP))))
1323			goto out;
1324
1325		skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
1326
1327		segs = NULL;
1328		goto out;
1329	}
1330
1331	/* Do software UFO. Complete and fill in the UDP checksum as HW cannot
1332	 * do checksum of UDP packets sent as multiple IP fragments.
1333	 */
1334	offset = skb_checksum_start_offset(skb);
1335	csum = skb_checksum(skb, offset, skb->len- offset, 0);
1336	offset += skb->csum_offset;
1337	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
1338	skb->ip_summed = CHECKSUM_NONE;
1339
1340	/* Check if there is enough headroom to insert fragment header. */
1341	if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) &&
1342	    pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
1343		goto out;
1344
1345	/* Find the unfragmentable header and shift it left by frag_hdr_sz
1346	 * bytes to insert fragment header.
1347	 */
1348	unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
1349	nexthdr = *prevhdr;
1350	*prevhdr = NEXTHDR_FRAGMENT;
1351	unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
1352		     unfrag_ip6hlen;
1353	mac_start = skb_mac_header(skb);
1354	memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
1355
1356	skb->mac_header -= frag_hdr_sz;
1357	skb->network_header -= frag_hdr_sz;
1358
1359	fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
1360	fptr->nexthdr = nexthdr;
1361	fptr->reserved = 0;
1362	ipv6_select_ident(fptr, (struct rt6_info *)skb_dst(skb));
1363
1364	/* Fragment the skb. ipv6 header and the remaining fields of the
1365	 * fragment header are updated in ipv6_gso_segment()
1366	 */
1367	segs = skb_segment(skb, features);
1368
1369out:
1370	return segs;
1371}
1372
1373static const struct inet6_protocol udpv6_protocol = {
1374	.handler	=	udpv6_rcv,
1375	.err_handler	=	udpv6_err,
1376	.gso_send_check =	udp6_ufo_send_check,
1377	.gso_segment	=	udp6_ufo_fragment,
1378	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1379};
1380
1381/* ------------------------------------------------------------------------ */
1382#ifdef CONFIG_PROC_FS
1383
1384static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1385{
1386	struct inet_sock *inet = inet_sk(sp);
1387	struct ipv6_pinfo *np = inet6_sk(sp);
1388	const struct in6_addr *dest, *src;
1389	__u16 destp, srcp;
1390
1391	dest  = &np->daddr;
1392	src   = &np->rcv_saddr;
1393	destp = ntohs(inet->inet_dport);
1394	srcp  = ntohs(inet->inet_sport);
1395	seq_printf(seq,
1396		   "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1397		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d\n",
1398		   bucket,
1399		   src->s6_addr32[0], src->s6_addr32[1],
1400		   src->s6_addr32[2], src->s6_addr32[3], srcp,
1401		   dest->s6_addr32[0], dest->s6_addr32[1],
1402		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
1403		   sp->sk_state,
1404		   sk_wmem_alloc_get(sp),
1405		   sk_rmem_alloc_get(sp),
1406		   0, 0L, 0,
1407		   sock_i_uid(sp), 0,
1408		   sock_i_ino(sp),
1409		   atomic_read(&sp->sk_refcnt), sp,
1410		   atomic_read(&sp->sk_drops));
1411}
1412
1413int udp6_seq_show(struct seq_file *seq, void *v)
1414{
1415	if (v == SEQ_START_TOKEN)
1416		seq_printf(seq,
1417			   "  sl  "
1418			   "local_address                         "
1419			   "remote_address                        "
1420			   "st tx_queue rx_queue tr tm->when retrnsmt"
1421			   "   uid  timeout inode ref pointer drops\n");
1422	else
1423		udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
 
1424	return 0;
1425}
1426
 
 
 
 
 
 
 
 
1427static struct udp_seq_afinfo udp6_seq_afinfo = {
1428	.name		= "udp6",
1429	.family		= AF_INET6,
1430	.udp_table	= &udp_table,
1431	.seq_fops	= {
1432		.owner	=	THIS_MODULE,
1433	},
1434	.seq_ops	= {
1435		.show		= udp6_seq_show,
1436	},
1437};
1438
1439int __net_init udp6_proc_init(struct net *net)
1440{
1441	return udp_proc_register(net, &udp6_seq_afinfo);
 
 
 
1442}
1443
1444void udp6_proc_exit(struct net *net) {
1445	udp_proc_unregister(net, &udp6_seq_afinfo);
 
1446}
1447#endif /* CONFIG_PROC_FS */
1448
1449/* ------------------------------------------------------------------------ */
1450
1451struct proto udpv6_prot = {
1452	.name		   = "UDPv6",
1453	.owner		   = THIS_MODULE,
1454	.close		   = udp_lib_close,
1455	.connect	   = ip6_datagram_connect,
1456	.disconnect	   = udp_disconnect,
1457	.ioctl		   = udp_ioctl,
1458	.destroy	   = udpv6_destroy_sock,
1459	.setsockopt	   = udpv6_setsockopt,
1460	.getsockopt	   = udpv6_getsockopt,
1461	.sendmsg	   = udpv6_sendmsg,
1462	.recvmsg	   = udpv6_recvmsg,
1463	.backlog_rcv	   = udpv6_queue_rcv_skb,
1464	.hash		   = udp_lib_hash,
1465	.unhash		   = udp_lib_unhash,
1466	.rehash		   = udp_v6_rehash,
1467	.get_port	   = udp_v6_get_port,
1468	.memory_allocated  = &udp_memory_allocated,
1469	.sysctl_mem	   = sysctl_udp_mem,
1470	.sysctl_wmem	   = &sysctl_udp_wmem_min,
1471	.sysctl_rmem	   = &sysctl_udp_rmem_min,
1472	.obj_size	   = sizeof(struct udp6_sock),
1473	.slab_flags	   = SLAB_DESTROY_BY_RCU,
1474	.h.udp_table	   = &udp_table,
1475#ifdef CONFIG_COMPAT
1476	.compat_setsockopt = compat_udpv6_setsockopt,
1477	.compat_getsockopt = compat_udpv6_getsockopt,
1478#endif
1479	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 
 
 
 
 
 
 
 
 
1480};
1481
1482static struct inet_protosw udpv6_protosw = {
1483	.type =      SOCK_DGRAM,
1484	.protocol =  IPPROTO_UDP,
1485	.prot =      &udpv6_prot,
1486	.ops =       &inet6_dgram_ops,
1487	.no_check =  UDP_CSUM_DEFAULT,
1488	.flags =     INET_PROTOSW_PERMANENT,
1489};
1490
1491
1492int __init udpv6_init(void)
1493{
1494	int ret;
1495
1496	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1497	if (ret)
1498		goto out;
1499
1500	ret = inet6_register_protosw(&udpv6_protosw);
1501	if (ret)
1502		goto out_udpv6_protocol;
1503out:
1504	return ret;
1505
1506out_udpv6_protocol:
1507	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1508	goto out;
1509}
1510
1511void udpv6_exit(void)
1512{
1513	inet6_unregister_protosw(&udpv6_protosw);
1514	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1515}
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	UDP over IPv6
   4 *	Linux INET6 implementation
   5 *
   6 *	Authors:
   7 *	Pedro Roque		<roque@di.fc.ul.pt>
   8 *
   9 *	Based on linux/ipv4/udp.c
  10 *
  11 *	Fixes:
  12 *	Hideaki YOSHIFUJI	:	sin6_scope_id support
  13 *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
  14 *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
  15 *					a single port at the same time.
  16 *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
  17 *      YOSHIFUJI Hideaki @USAGI:	convert /proc/net/udp6 to seq_file.
 
 
 
 
 
  18 */
  19
  20#include <linux/bpf-cgroup.h>
  21#include <linux/errno.h>
  22#include <linux/types.h>
  23#include <linux/socket.h>
  24#include <linux/sockios.h>
  25#include <linux/net.h>
  26#include <linux/in6.h>
  27#include <linux/netdevice.h>
  28#include <linux/if_arp.h>
  29#include <linux/ipv6.h>
  30#include <linux/icmpv6.h>
  31#include <linux/init.h>
  32#include <linux/module.h>
  33#include <linux/skbuff.h>
  34#include <linux/slab.h>
  35#include <linux/uaccess.h>
  36#include <linux/indirect_call_wrapper.h>
  37
  38#include <net/addrconf.h>
  39#include <net/ndisc.h>
  40#include <net/protocol.h>
  41#include <net/transp_v6.h>
  42#include <net/ip6_route.h>
  43#include <net/raw.h>
  44#include <net/seg6.h>
  45#include <net/tcp_states.h>
  46#include <net/ip6_checksum.h>
  47#include <net/ip6_tunnel.h>
  48#include <net/xfrm.h>
  49#include <net/inet_hashtables.h>
  50#include <net/inet6_hashtables.h>
  51#include <net/busy_poll.h>
  52#include <net/sock_reuseport.h>
  53
  54#include <linux/proc_fs.h>
  55#include <linux/seq_file.h>
  56#include <trace/events/skb.h>
  57#include "udp_impl.h"
  58
  59static void udpv6_destruct_sock(struct sock *sk)
  60{
  61	udp_destruct_common(sk);
  62	inet6_sock_destruct(sk);
  63}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  64
  65int udpv6_init_sock(struct sock *sk)
  66{
  67	udp_lib_init_sock(sk);
  68	sk->sk_destruct = udpv6_destruct_sock;
  69	set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
  70	return 0;
  71}
  72
  73static u32 udp6_ehashfn(const struct net *net,
  74			const struct in6_addr *laddr,
  75			const u16 lport,
  76			const struct in6_addr *faddr,
  77			const __be16 fport)
  78{
  79	static u32 udp6_ehash_secret __read_mostly;
  80	static u32 udp_ipv6_hash_secret __read_mostly;
  81
  82	u32 lhash, fhash;
  83
  84	net_get_random_once(&udp6_ehash_secret,
  85			    sizeof(udp6_ehash_secret));
  86	net_get_random_once(&udp_ipv6_hash_secret,
  87			    sizeof(udp_ipv6_hash_secret));
  88
  89	lhash = (__force u32)laddr->s6_addr32[3];
  90	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
  91
  92	return __inet6_ehashfn(lhash, lport, fhash, fport,
  93			       udp_ipv6_hash_secret + net_hash_mix(net));
  94}
  95
  96int udp_v6_get_port(struct sock *sk, unsigned short snum)
  97{
  98	unsigned int hash2_nulladdr =
  99		ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
 100	unsigned int hash2_partial =
 101		ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
 102
 103	/* precompute partial secondary hash */
 104	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
 105	return udp_lib_get_port(sk, snum, hash2_nulladdr);
 106}
 107
 108void udp_v6_rehash(struct sock *sk)
 109{
 110	u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
 111					  &sk->sk_v6_rcv_saddr,
 112					  inet_sk(sk)->inet_num);
 113
 114	udp_lib_rehash(sk, new_hash);
 115}
 116
 117static int compute_score(struct sock *sk, struct net *net,
 118			 const struct in6_addr *saddr, __be16 sport,
 119			 const struct in6_addr *daddr, unsigned short hnum,
 120			 int dif, int sdif)
 121{
 122	int bound_dev_if, score;
 123	struct inet_sock *inet;
 124	bool dev_match;
 125
 126	if (!net_eq(sock_net(sk), net) ||
 127	    udp_sk(sk)->udp_port_hash != hnum ||
 128	    sk->sk_family != PF_INET6)
 129		return -1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 130
 131	if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 132		return -1;
 
 
 
 
 
 
 
 
 
 
 133
 134	score = 0;
 135	inet = inet_sk(sk);
 136
 137	if (inet->inet_dport) {
 138		if (inet->inet_dport != sport)
 139			return -1;
 140		score++;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 141	}
 142
 143	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 144		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 145			return -1;
 146		score++;
 147	}
 148
 149	bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
 150	dev_match = udp_sk_bound_dev_eq(net, bound_dev_if, dif, sdif);
 151	if (!dev_match)
 152		return -1;
 153	if (bound_dev_if)
 154		score++;
 155
 156	if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
 157		score++;
 158
 159	return score;
 160}
 161
 162static struct sock *lookup_reuseport(struct net *net, struct sock *sk,
 163				     struct sk_buff *skb,
 164				     const struct in6_addr *saddr,
 165				     __be16 sport,
 166				     const struct in6_addr *daddr,
 167				     unsigned int hnum)
 168{
 169	struct sock *reuse_sk = NULL;
 170	u32 hash;
 171
 172	if (sk->sk_reuseport && sk->sk_state != TCP_ESTABLISHED) {
 173		hash = udp6_ehashfn(net, daddr, hnum, saddr, sport);
 174		reuse_sk = reuseport_select_sock(sk, hash, skb,
 175						 sizeof(struct udphdr));
 176	}
 177	return reuse_sk;
 178}
 179
 180/* called with rcu_read_lock() */
 181static struct sock *udp6_lib_lookup2(struct net *net,
 182		const struct in6_addr *saddr, __be16 sport,
 183		const struct in6_addr *daddr, unsigned int hnum,
 184		int dif, int sdif, struct udp_hslot *hslot2,
 185		struct sk_buff *skb)
 186{
 187	struct sock *sk, *result;
 
 188	int score, badness;
 189
 
 190	result = NULL;
 191	badness = -1;
 192	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
 193		score = compute_score(sk, net, saddr, sport,
 194				      daddr, hnum, dif, sdif);
 195		if (score > badness) {
 196			result = lookup_reuseport(net, sk, skb,
 197						  saddr, sport, daddr, hnum);
 198			/* Fall back to scoring if group has connections */
 199			if (result && !reuseport_has_conns(sk))
 200				return result;
 
 
 
 
 
 
 
 
 201
 202			result = result ? : sk;
 203			badness = score;
 
 
 
 
 
 
 204		}
 205	}
 206	return result;
 207}
 208
 209static inline struct sock *udp6_lookup_run_bpf(struct net *net,
 210					       struct udp_table *udptable,
 211					       struct sk_buff *skb,
 212					       const struct in6_addr *saddr,
 213					       __be16 sport,
 214					       const struct in6_addr *daddr,
 215					       u16 hnum, const int dif)
 216{
 217	struct sock *sk, *reuse_sk;
 218	bool no_reuseport;
 219
 220	if (udptable != net->ipv4.udp_table)
 221		return NULL; /* only UDP is supported */
 222
 223	no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP, saddr, sport,
 224					    daddr, hnum, dif, &sk);
 225	if (no_reuseport || IS_ERR_OR_NULL(sk))
 226		return sk;
 227
 228	reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
 229	if (reuse_sk)
 230		sk = reuse_sk;
 231	return sk;
 232}
 233
 234/* rcu_read_lock() must be held */
 235struct sock *__udp6_lib_lookup(struct net *net,
 236			       const struct in6_addr *saddr, __be16 sport,
 237			       const struct in6_addr *daddr, __be16 dport,
 238			       int dif, int sdif, struct udp_table *udptable,
 239			       struct sk_buff *skb)
 240{
 
 
 241	unsigned short hnum = ntohs(dport);
 242	unsigned int hash2, slot2;
 243	struct udp_hslot *hslot2;
 244	struct sock *result, *sk;
 245
 246	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
 247	slot2 = hash2 & udptable->mask;
 248	hslot2 = &udptable->hash2[slot2];
 249
 250	/* Lookup connected or non-wildcard sockets */
 251	result = udp6_lib_lookup2(net, saddr, sport,
 252				  daddr, hnum, dif, sdif,
 253				  hslot2, skb);
 254	if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
 255		goto done;
 256
 257	/* Lookup redirect from BPF */
 258	if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
 259		sk = udp6_lookup_run_bpf(net, udptable, skb,
 260					 saddr, sport, daddr, hnum, dif);
 261		if (sk) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 262			result = sk;
 263			goto done;
 264		}
 265	}
 
 
 
 
 
 
 
 266
 267	/* Got non-wildcard socket or error on first lookup */
 268	if (result)
 269		goto done;
 270
 271	/* Lookup wildcard sockets */
 272	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
 273	slot2 = hash2 & udptable->mask;
 274	hslot2 = &udptable->hash2[slot2];
 275
 276	result = udp6_lib_lookup2(net, saddr, sport,
 277				  &in6addr_any, hnum, dif, sdif,
 278				  hslot2, skb);
 279done:
 280	if (IS_ERR(result))
 281		return NULL;
 282	return result;
 283}
 284EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
 285
 286static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
 287					  __be16 sport, __be16 dport,
 288					  struct udp_table *udptable)
 289{
 
 290	const struct ipv6hdr *iph = ipv6_hdr(skb);
 291
 292	return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
 
 
 293				 &iph->daddr, dport, inet6_iif(skb),
 294				 inet6_sdif(skb), udptable, skb);
 295}
 296
 297struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
 298				 __be16 sport, __be16 dport)
 299{
 300	const struct ipv6hdr *iph = ipv6_hdr(skb);
 301	struct net *net = dev_net(skb->dev);
 302
 303	return __udp6_lib_lookup(net, &iph->saddr, sport,
 304				 &iph->daddr, dport, inet6_iif(skb),
 305				 inet6_sdif(skb), net->ipv4.udp_table, NULL);
 306}
 307
 308/* Must be called under rcu_read_lock().
 309 * Does increment socket refcount.
 310 */
 311#if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
 312struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
 313			     const struct in6_addr *daddr, __be16 dport, int dif)
 314{
 315	struct sock *sk;
 316
 317	sk =  __udp6_lib_lookup(net, saddr, sport, daddr, dport,
 318				dif, 0, net->ipv4.udp_table, NULL);
 319	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
 320		sk = NULL;
 321	return sk;
 322}
 323EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 324#endif
 325
 326/* do not use the scratch area len for jumbogram: their length execeeds the
 327 * scratch area space; note that the IP6CB flags is still in the first
 328 * cacheline, so checking for jumbograms is cheap
 329 */
 330static int udp6_skb_len(struct sk_buff *skb)
 331{
 332	return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
 333}
 334
 335/*
 336 *	This should be easy, if there is something there we
 337 *	return it, otherwise we block.
 338 */
 339
 340int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 341		  int flags, int *addr_len)
 
 342{
 343	struct ipv6_pinfo *np = inet6_sk(sk);
 344	struct inet_sock *inet = inet_sk(sk);
 345	struct sk_buff *skb;
 346	unsigned int ulen, copied;
 347	int off, err, peeking = flags & MSG_PEEK;
 
 348	int is_udplite = IS_UDPLITE(sk);
 349	struct udp_mib __percpu *mib;
 350	bool checksum_valid = false;
 351	int is_udp4;
 
 
 
 
 352
 353	if (flags & MSG_ERRQUEUE)
 354		return ipv6_recv_error(sk, msg, len, addr_len);
 355
 356	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 357		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 358
 359try_again:
 360	off = sk_peek_offset(sk, flags);
 361	skb = __skb_recv_udp(sk, flags, &off, &err);
 362	if (!skb)
 363		return err;
 364
 365	ulen = udp6_skb_len(skb);
 366	copied = len;
 367	if (copied > ulen - off)
 368		copied = ulen - off;
 369	else if (copied < ulen)
 370		msg->msg_flags |= MSG_TRUNC;
 371
 372	is_udp4 = (skb->protocol == htons(ETH_P_IP));
 373	mib = __UDPX_MIB(sk, is_udp4);
 374
 375	/*
 376	 * If checksum is needed at all, try to do it while copying the
 377	 * data.  If the data is truncated, or if we only want a partial
 378	 * coverage checksum (UDP-Lite), do it before the copy.
 379	 */
 380
 381	if (copied < ulen || peeking ||
 382	    (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
 383		checksum_valid = udp_skb_csum_unnecessary(skb) ||
 384				!__udp_lib_checksum_complete(skb);
 385		if (!checksum_valid)
 386			goto csum_copy_err;
 387	}
 388
 389	if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
 390		if (udp_skb_is_linear(skb))
 391			err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
 392		else
 393			err = skb_copy_datagram_msg(skb, off, msg, copied);
 394	} else {
 395		err = skb_copy_and_csum_datagram_msg(skb, off, msg);
 396		if (err == -EINVAL)
 397			goto csum_copy_err;
 398	}
 399	if (unlikely(err)) {
 400		if (!peeking) {
 401			atomic_inc(&sk->sk_drops);
 402			SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 403		}
 404		kfree_skb(skb);
 405		return err;
 
 
 
 406	}
 407	if (!peeking)
 408		SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS);
 409
 410	sock_recv_cmsgs(msg, sk, skb);
 411
 412	/* Copy the address. */
 413	if (msg->msg_name) {
 414		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 
 
 415		sin6->sin6_family = AF_INET6;
 416		sin6->sin6_port = udp_hdr(skb)->source;
 417		sin6->sin6_flowinfo = 0;
 
 418
 419		if (is_udp4) {
 420			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 421					       &sin6->sin6_addr);
 422			sin6->sin6_scope_id = 0;
 423		} else {
 424			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 425			sin6->sin6_scope_id =
 426				ipv6_iface_scope_id(&sin6->sin6_addr,
 427						    inet6_iif(skb));
 428		}
 429		*addr_len = sizeof(*sin6);
 430
 431		BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk,
 432						      (struct sockaddr *)sin6);
 433	}
 434
 435	if (udp_sk(sk)->gro_enabled)
 436		udp_cmsg_recv(msg, sk, skb);
 437
 438	if (np->rxopt.all)
 439		ip6_datagram_recv_common_ctl(sk, msg, skb);
 440
 441	if (is_udp4) {
 442		if (inet->cmsg_flags)
 443			ip_cmsg_recv_offset(msg, sk, skb,
 444					    sizeof(struct udphdr), off);
 445	} else {
 446		if (np->rxopt.all)
 447			ip6_datagram_recv_specific_ctl(sk, msg, skb);
 448	}
 449
 450	err = copied;
 451	if (flags & MSG_TRUNC)
 452		err = ulen;
 453
 454	skb_consume_udp(sk, skb, peeking ? -err : err);
 
 
 455	return err;
 456
 457csum_copy_err:
 458	if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
 459				 udp_skb_destructor)) {
 460		SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS);
 461		SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 
 
 
 
 462	}
 463	kfree_skb(skb);
 
 
 
 464
 465	/* starting over for a new packet, but check if we need to yield */
 466	cond_resched();
 467	msg->msg_flags &= ~MSG_TRUNC;
 468	goto try_again;
 469}
 470
 471DEFINE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
 472void udpv6_encap_enable(void)
 473{
 474	static_branch_inc(&udpv6_encap_needed_key);
 475}
 476EXPORT_SYMBOL(udpv6_encap_enable);
 477
 478/* Handler for tunnels with arbitrary destination ports: no socket lookup, go
 479 * through error handlers in encapsulations looking for a match.
 480 */
 481static int __udp6_lib_err_encap_no_sk(struct sk_buff *skb,
 482				      struct inet6_skb_parm *opt,
 483				      u8 type, u8 code, int offset, __be32 info)
 484{
 485	int i;
 486
 487	for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) {
 488		int (*handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
 489			       u8 type, u8 code, int offset, __be32 info);
 490		const struct ip6_tnl_encap_ops *encap;
 491
 492		encap = rcu_dereference(ip6tun_encaps[i]);
 493		if (!encap)
 494			continue;
 495		handler = encap->err_handler;
 496		if (handler && !handler(skb, opt, type, code, offset, info))
 497			return 0;
 498	}
 499
 500	return -ENOENT;
 501}
 502
 503/* Try to match ICMP errors to UDP tunnels by looking up a socket without
 504 * reversing source and destination port: this will match tunnels that force the
 505 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that
 506 * lwtunnels might actually break this assumption by being configured with
 507 * different destination ports on endpoints, in this case we won't be able to
 508 * trace ICMP messages back to them.
 509 *
 510 * If this doesn't match any socket, probe tunnels with arbitrary destination
 511 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port
 512 * we've sent packets to won't necessarily match the local destination port.
 513 *
 514 * Then ask the tunnel implementation to match the error against a valid
 515 * association.
 516 *
 517 * Return an error if we can't find a match, the socket if we need further
 518 * processing, zero otherwise.
 519 */
 520static struct sock *__udp6_lib_err_encap(struct net *net,
 521					 const struct ipv6hdr *hdr, int offset,
 522					 struct udphdr *uh,
 523					 struct udp_table *udptable,
 524					 struct sock *sk,
 525					 struct sk_buff *skb,
 526					 struct inet6_skb_parm *opt,
 527					 u8 type, u8 code, __be32 info)
 528{
 529	int (*lookup)(struct sock *sk, struct sk_buff *skb);
 530	int network_offset, transport_offset;
 531	struct udp_sock *up;
 532
 533	network_offset = skb_network_offset(skb);
 534	transport_offset = skb_transport_offset(skb);
 535
 536	/* Network header needs to point to the outer IPv6 header inside ICMP */
 537	skb_reset_network_header(skb);
 538
 539	/* Transport header needs to point to the UDP header */
 540	skb_set_transport_header(skb, offset);
 541
 542	if (sk) {
 543		up = udp_sk(sk);
 544
 545		lookup = READ_ONCE(up->encap_err_lookup);
 546		if (lookup && lookup(sk, skb))
 547			sk = NULL;
 548
 549		goto out;
 550	}
 551
 552	sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source,
 553			       &hdr->saddr, uh->dest,
 554			       inet6_iif(skb), 0, udptable, skb);
 555	if (sk) {
 556		up = udp_sk(sk);
 557
 558		lookup = READ_ONCE(up->encap_err_lookup);
 559		if (!lookup || lookup(sk, skb))
 560			sk = NULL;
 561	}
 562
 563out:
 564	if (!sk) {
 565		sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code,
 566							offset, info));
 567	}
 568
 569	skb_set_transport_header(skb, transport_offset);
 570	skb_set_network_header(skb, network_offset);
 571
 572	return sk;
 573}
 574
 575int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 576		   u8 type, u8 code, int offset, __be32 info,
 577		   struct udp_table *udptable)
 578{
 579	struct ipv6_pinfo *np;
 580	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
 581	const struct in6_addr *saddr = &hdr->saddr;
 582	const struct in6_addr *daddr = seg6_get_daddr(skb, opt) ? : &hdr->daddr;
 583	struct udphdr *uh = (struct udphdr *)(skb->data+offset);
 584	bool tunnel = false;
 585	struct sock *sk;
 586	int harderr;
 587	int err;
 588	struct net *net = dev_net(skb->dev);
 589
 590	sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
 591			       inet6_iif(skb), inet6_sdif(skb), udptable, NULL);
 
 
 592
 593	if (!sk || udp_sk(sk)->encap_type) {
 594		/* No socket for error: try tunnels before discarding */
 595		if (static_branch_unlikely(&udpv6_encap_needed_key)) {
 596			sk = __udp6_lib_err_encap(net, hdr, offset, uh,
 597						  udptable, sk, skb,
 598						  opt, type, code, info);
 599			if (!sk)
 600				return 0;
 601		} else
 602			sk = ERR_PTR(-ENOENT);
 603
 604		if (IS_ERR(sk)) {
 605			__ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
 606					  ICMP6_MIB_INERRORS);
 607			return PTR_ERR(sk);
 608		}
 609
 610		tunnel = true;
 611	}
 612
 613	harderr = icmpv6_err_convert(type, code, &err);
 614	np = inet6_sk(sk);
 615
 616	if (type == ICMPV6_PKT_TOOBIG) {
 617		if (!ip6_sk_accept_pmtu(sk))
 618			goto out;
 619		ip6_sk_update_pmtu(skb, sk, info);
 620		if (np->pmtudisc != IPV6_PMTUDISC_DONT)
 621			harderr = 1;
 622	}
 623	if (type == NDISC_REDIRECT) {
 624		if (tunnel) {
 625			ip6_redirect(skb, sock_net(sk), inet6_iif(skb),
 626				     sk->sk_mark, sk->sk_uid);
 627		} else {
 628			ip6_sk_redirect(skb, sk);
 629		}
 630		goto out;
 631	}
 632
 633	/* Tunnels don't have an application socket: don't pass errors back */
 634	if (tunnel) {
 635		if (udp_sk(sk)->encap_err_rcv)
 636			udp_sk(sk)->encap_err_rcv(sk, skb, err, uh->dest,
 637						  ntohl(info), (u8 *)(uh+1));
 638		goto out;
 639	}
 640
 641	if (!np->recverr) {
 642		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 643			goto out;
 644	} else {
 645		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 646	}
 647
 648	sk->sk_err = err;
 649	sk_error_report(sk);
 650out:
 651	return 0;
 652}
 653
 654static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 655{
 656	int rc;
 657
 658	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 659		sock_rps_save_rxhash(sk, skb);
 660		sk_mark_napi_id(sk, skb);
 661		sk_incoming_cpu_update(sk);
 662	} else {
 663		sk_mark_napi_id_once(sk, skb);
 664	}
 665
 666	rc = __udp_enqueue_schedule_skb(sk, skb);
 667	if (rc < 0) {
 668		int is_udplite = IS_UDPLITE(sk);
 669		enum skb_drop_reason drop_reason;
 670
 671		/* Note that an ENOMEM error is charged twice */
 672		if (rc == -ENOMEM) {
 673			UDP6_INC_STATS(sock_net(sk),
 674					 UDP_MIB_RCVBUFERRORS, is_udplite);
 675			drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
 676		} else {
 677			UDP6_INC_STATS(sock_net(sk),
 678				       UDP_MIB_MEMERRORS, is_udplite);
 679			drop_reason = SKB_DROP_REASON_PROTO_MEM;
 680		}
 681		UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 682		kfree_skb_reason(skb, drop_reason);
 683		return -1;
 684	}
 685
 686	return 0;
 687}
 688
 689static __inline__ int udpv6_err(struct sk_buff *skb,
 690				struct inet6_skb_parm *opt, u8 type,
 691				u8 code, int offset, __be32 info)
 692{
 693	return __udp6_lib_err(skb, opt, type, code, offset, info,
 694			      dev_net(skb->dev)->ipv4.udp_table);
 695}
 696
 697static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
 698{
 699	enum skb_drop_reason drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
 700	struct udp_sock *up = udp_sk(sk);
 
 701	int is_udplite = IS_UDPLITE(sk);
 702
 703	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
 704		drop_reason = SKB_DROP_REASON_XFRM_POLICY;
 
 
 705		goto drop;
 706	}
 707
 708	if (static_branch_unlikely(&udpv6_encap_needed_key) && up->encap_type) {
 709		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
 710
 711		/*
 712		 * This is an encapsulation socket so pass the skb to
 713		 * the socket's udp_encap_rcv() hook. Otherwise, just
 714		 * fall through and pass this up the UDP socket.
 715		 * up->encap_rcv() returns the following value:
 716		 * =0 if skb was successfully passed to the encap
 717		 *    handler or was discarded by it.
 718		 * >0 if skb should be passed on to UDP.
 719		 * <0 if skb should be resubmitted as proto -N
 720		 */
 721
 722		/* if we're overly short, let UDP handle it */
 723		encap_rcv = READ_ONCE(up->encap_rcv);
 724		if (encap_rcv) {
 725			int ret;
 726
 727			/* Verify checksum before giving to encap */
 728			if (udp_lib_checksum_complete(skb))
 729				goto csum_error;
 730
 731			ret = encap_rcv(sk, skb);
 732			if (ret <= 0) {
 733				__UDP6_INC_STATS(sock_net(sk),
 734						 UDP_MIB_INDATAGRAMS,
 735						 is_udplite);
 736				return -ret;
 737			}
 738		}
 739
 740		/* FALLTHROUGH -- it's a UDP Packet */
 741	}
 742
 743	/*
 744	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
 745	 */
 746	if ((up->pcflag & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
 747
 748		if (up->pcrlen == 0) {          /* full coverage was set  */
 749			net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
 750					    UDP_SKB_CB(skb)->cscov, skb->len);
 
 751			goto drop;
 752		}
 753		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
 754			net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
 755					    UDP_SKB_CB(skb)->cscov, up->pcrlen);
 
 756			goto drop;
 757		}
 758	}
 759
 760	prefetch(&sk->sk_rmem_alloc);
 761	if (rcu_access_pointer(sk->sk_filter) &&
 762	    udp_lib_checksum_complete(skb))
 763		goto csum_error;
 764
 765	if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) {
 766		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
 767		goto drop;
 
 
 
 768	}
 769
 770	udp_csum_pull_header(skb);
 771
 772	skb_dst_drop(skb);
 773
 774	return __udpv6_queue_rcv_skb(sk, skb);
 775
 776csum_error:
 777	drop_reason = SKB_DROP_REASON_UDP_CSUM;
 778	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 779drop:
 780	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 781	atomic_inc(&sk->sk_drops);
 782	kfree_skb_reason(skb, drop_reason);
 
 
 783	return -1;
 784}
 785
 786static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 787{
 788	struct sk_buff *next, *segs;
 789	int ret;
 
 
 
 
 
 
 
 790
 791	if (likely(!udp_unexpected_gso(sk, skb)))
 792		return udpv6_queue_rcv_one_skb(sk, skb);
 793
 794	__skb_push(skb, -skb_mac_offset(skb));
 795	segs = udp_rcv_segment(sk, skb, false);
 796	skb_list_walk_safe(segs, skb, next) {
 797		__skb_pull(skb, skb_transport_offset(skb));
 798
 799		udp_post_segment_fix_csum(skb);
 800		ret = udpv6_queue_rcv_one_skb(sk, skb);
 801		if (ret > 0)
 802			ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret,
 803						 true);
 
 
 
 
 
 
 
 
 
 
 
 
 804	}
 805	return 0;
 806}
 807
 808static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
 809				   __be16 loc_port, const struct in6_addr *loc_addr,
 810				   __be16 rmt_port, const struct in6_addr *rmt_addr,
 811				   int dif, int sdif, unsigned short hnum)
 812{
 813	struct inet_sock *inet = inet_sk(sk);
 
 
 814
 815	if (!net_eq(sock_net(sk), net))
 816		return false;
 817
 818	if (udp_sk(sk)->udp_port_hash != hnum ||
 819	    sk->sk_family != PF_INET6 ||
 820	    (inet->inet_dport && inet->inet_dport != rmt_port) ||
 821	    (!ipv6_addr_any(&sk->sk_v6_daddr) &&
 822		    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
 823	    !udp_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif, sdif) ||
 824	    (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 825		    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
 826		return false;
 827	if (!inet6_mc_check(sk, loc_addr, rmt_addr))
 828		return false;
 829	return true;
 830}
 831
 832static void udp6_csum_zero_error(struct sk_buff *skb)
 833{
 834	/* RFC 2460 section 8.1 says that we SHOULD log
 835	 * this error. Well, it is reasonable.
 836	 */
 837	net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
 838			    &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
 839			    &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
 
 
 840}
 841
 842/*
 843 * Note: called only from the BH handler context,
 844 * so we don't need to lock the hashes.
 845 */
 846static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 847		const struct in6_addr *saddr, const struct in6_addr *daddr,
 848		struct udp_table *udptable, int proto)
 849{
 850	struct sock *sk, *first = NULL;
 851	const struct udphdr *uh = udp_hdr(skb);
 852	unsigned short hnum = ntohs(uh->dest);
 853	struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
 854	unsigned int offset = offsetof(typeof(*sk), sk_node);
 855	unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
 856	int dif = inet6_iif(skb);
 857	int sdif = inet6_sdif(skb);
 858	struct hlist_node *node;
 859	struct sk_buff *nskb;
 860
 861	if (use_hash2) {
 862		hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
 863			    udptable->mask;
 864		hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
 865start_lookup:
 866		hslot = &udptable->hash2[hash2];
 867		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 868	}
 869
 870	sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
 871		if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
 872					    uh->source, saddr, dif, sdif,
 873					    hnum))
 874			continue;
 875		/* If zero checksum and no_check is not on for
 876		 * the socket then skip it.
 877		 */
 878		if (!uh->check && !udp_sk(sk)->no_check6_rx)
 879			continue;
 880		if (!first) {
 881			first = sk;
 882			continue;
 883		}
 884		nskb = skb_clone(skb, GFP_ATOMIC);
 885		if (unlikely(!nskb)) {
 886			atomic_inc(&sk->sk_drops);
 887			__UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
 888					 IS_UDPLITE(sk));
 889			__UDP6_INC_STATS(net, UDP_MIB_INERRORS,
 890					 IS_UDPLITE(sk));
 891			continue;
 892		}
 
 
 
 
 
 
 893
 894		if (udpv6_queue_rcv_skb(sk, nskb) > 0)
 895			consume_skb(nskb);
 896	}
 897
 898	/* Also lookup *:port if we are using hash2 and haven't done so yet. */
 899	if (use_hash2 && hash2 != hash2_any) {
 900		hash2 = hash2_any;
 901		goto start_lookup;
 902	}
 903
 904	if (first) {
 905		if (udpv6_queue_rcv_skb(first, skb) > 0)
 906			consume_skb(skb);
 907	} else {
 908		kfree_skb(skb);
 909		__UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
 910				 proto == IPPROTO_UDPLITE);
 911	}
 912	return 0;
 913}
 914
 915static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
 
 916{
 917	if (udp_sk_rx_dst_set(sk, dst)) {
 918		const struct rt6_info *rt = (const struct rt6_info *)dst;
 
 
 919
 920		sk->sk_rx_dst_cookie = rt6_get_cookie(rt);
 
 
 
 921	}
 922}
 923
 924/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
 925 * return code conversion for ip layer consumption
 926 */
 927static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
 928				struct udphdr *uh)
 929{
 930	int ret;
 931
 932	if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
 933		skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo);
 
 
 
 
 
 
 934
 935	ret = udpv6_queue_rcv_skb(sk, skb);
 936
 937	/* a return value > 0 means to resubmit the input */
 938	if (ret > 0)
 939		return ret;
 940	return 0;
 941}
 942
 943int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 944		   int proto)
 945{
 946	enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
 947	const struct in6_addr *saddr, *daddr;
 948	struct net *net = dev_net(skb->dev);
 
 949	struct udphdr *uh;
 950	struct sock *sk;
 951	bool refcounted;
 952	u32 ulen = 0;
 953
 954	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 955		goto discard;
 956
 957	saddr = &ipv6_hdr(skb)->saddr;
 958	daddr = &ipv6_hdr(skb)->daddr;
 959	uh = udp_hdr(skb);
 960
 961	ulen = ntohs(uh->len);
 962	if (ulen > skb->len)
 963		goto short_packet;
 964
 965	if (proto == IPPROTO_UDP) {
 966		/* UDP validates ulen. */
 967
 968		/* Check for jumbo payload */
 969		if (ulen == 0)
 970			ulen = skb->len;
 971
 972		if (ulen < sizeof(*uh))
 973			goto short_packet;
 974
 975		if (ulen < skb->len) {
 976			if (pskb_trim_rcsum(skb, ulen))
 977				goto short_packet;
 978			saddr = &ipv6_hdr(skb)->saddr;
 979			daddr = &ipv6_hdr(skb)->daddr;
 980			uh = udp_hdr(skb);
 981		}
 982	}
 983
 984	if (udp6_csum_init(skb, uh, proto))
 985		goto csum_error;
 986
 987	/* Check if the socket is already available, e.g. due to early demux */
 988	sk = skb_steal_sock(skb, &refcounted);
 989	if (sk) {
 990		struct dst_entry *dst = skb_dst(skb);
 991		int ret;
 992
 993		if (unlikely(rcu_dereference(sk->sk_rx_dst) != dst))
 994			udp6_sk_rx_dst_set(sk, dst);
 995
 996		if (!uh->check && !udp_sk(sk)->no_check6_rx) {
 997			if (refcounted)
 998				sock_put(sk);
 999			goto report_csum_error;
1000		}
1001
1002		ret = udp6_unicast_rcv_skb(sk, skb, uh);
1003		if (refcounted)
1004			sock_put(sk);
1005		return ret;
1006	}
1007
1008	/*
1009	 *	Multicast receive code
1010	 */
1011	if (ipv6_addr_is_multicast(daddr))
1012		return __udp6_lib_mcast_deliver(net, skb,
1013				saddr, daddr, udptable, proto);
1014
1015	/* Unicast */
 
 
 
 
 
1016	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
1017	if (sk) {
1018		if (!uh->check && !udp_sk(sk)->no_check6_rx)
1019			goto report_csum_error;
1020		return udp6_unicast_rcv_skb(sk, skb, uh);
1021	}
1022
1023	reason = SKB_DROP_REASON_NO_SOCKET;
 
 
 
 
 
 
 
1024
1025	if (!uh->check)
1026		goto report_csum_error;
1027
1028	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1029		goto discard;
 
1030
1031	if (udp_lib_checksum_complete(skb))
1032		goto csum_error;
1033
1034	__UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
1035	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
1036
1037	kfree_skb_reason(skb, reason);
 
 
 
 
 
 
 
 
 
 
 
1038	return 0;
1039
1040short_packet:
1041	if (reason == SKB_DROP_REASON_NOT_SPECIFIED)
1042		reason = SKB_DROP_REASON_PKT_TOO_SMALL;
1043	net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
1044			    proto == IPPROTO_UDPLITE ? "-Lite" : "",
1045			    saddr, ntohs(uh->source),
1046			    ulen, skb->len,
1047			    daddr, ntohs(uh->dest));
1048	goto discard;
1049
1050report_csum_error:
1051	udp6_csum_zero_error(skb);
1052csum_error:
1053	if (reason == SKB_DROP_REASON_NOT_SPECIFIED)
1054		reason = SKB_DROP_REASON_UDP_CSUM;
1055	__UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
1056discard:
1057	__UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
1058	kfree_skb_reason(skb, reason);
1059	return 0;
1060}
1061
1062
1063static struct sock *__udp6_lib_demux_lookup(struct net *net,
1064			__be16 loc_port, const struct in6_addr *loc_addr,
1065			__be16 rmt_port, const struct in6_addr *rmt_addr,
1066			int dif, int sdif)
1067{
1068	struct udp_table *udptable = net->ipv4.udp_table;
1069	unsigned short hnum = ntohs(loc_port);
1070	unsigned int hash2, slot2;
1071	struct udp_hslot *hslot2;
1072	__portpair ports;
1073	struct sock *sk;
1074
1075	hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
1076	slot2 = hash2 & udptable->mask;
1077	hslot2 = &udptable->hash2[slot2];
1078	ports = INET_COMBINED_PORTS(rmt_port, hnum);
1079
1080	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
1081		if (sk->sk_state == TCP_ESTABLISHED &&
1082		    inet6_match(net, sk, rmt_addr, loc_addr, ports, dif, sdif))
1083			return sk;
1084		/* Only check first socket in chain */
1085		break;
1086	}
1087	return NULL;
1088}
1089
1090void udp_v6_early_demux(struct sk_buff *skb)
1091{
1092	struct net *net = dev_net(skb->dev);
1093	const struct udphdr *uh;
1094	struct sock *sk;
1095	struct dst_entry *dst;
1096	int dif = skb->dev->ifindex;
1097	int sdif = inet6_sdif(skb);
1098
1099	if (!pskb_may_pull(skb, skb_transport_offset(skb) +
1100	    sizeof(struct udphdr)))
1101		return;
1102
1103	uh = udp_hdr(skb);
1104
1105	if (skb->pkt_type == PACKET_HOST)
1106		sk = __udp6_lib_demux_lookup(net, uh->dest,
1107					     &ipv6_hdr(skb)->daddr,
1108					     uh->source, &ipv6_hdr(skb)->saddr,
1109					     dif, sdif);
1110	else
1111		return;
1112
1113	if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
1114		return;
1115
1116	skb->sk = sk;
1117	skb->destructor = sock_efree;
1118	dst = rcu_dereference(sk->sk_rx_dst);
1119
1120	if (dst)
1121		dst = dst_check(dst, sk->sk_rx_dst_cookie);
1122	if (dst) {
1123		/* set noref for now.
1124		 * any place which wants to hold dst has to call
1125		 * dst_hold_safe()
1126		 */
1127		skb_dst_set_noref(skb, dst);
1128	}
1129}
1130
1131INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb)
1132{
1133	return __udp6_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP);
1134}
1135
1136/*
1137 * Throw away all pending data and cancel the corking. Socket is locked.
1138 */
1139static void udp_v6_flush_pending_frames(struct sock *sk)
1140{
1141	struct udp_sock *up = udp_sk(sk);
1142
1143	if (up->pending == AF_INET)
1144		udp_flush_pending_frames(sk);
1145	else if (up->pending) {
1146		up->len = 0;
1147		up->pending = 0;
1148		ip6_flush_pending_frames(sk);
1149	}
1150}
1151
1152static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
1153			     int addr_len)
1154{
1155	if (addr_len < offsetofend(struct sockaddr, sa_family))
1156		return -EINVAL;
1157	/* The following checks are replicated from __ip6_datagram_connect()
1158	 * and intended to prevent BPF program called below from accessing
1159	 * bytes that are out of the bound specified by user in addr_len.
1160	 */
1161	if (uaddr->sa_family == AF_INET) {
1162		if (ipv6_only_sock(sk))
1163			return -EAFNOSUPPORT;
1164		return udp_pre_connect(sk, uaddr, addr_len);
1165	}
1166
1167	if (addr_len < SIN6_LEN_RFC2133)
1168		return -EINVAL;
1169
1170	return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr);
1171}
1172
1173/**
1174 *	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
1175 *	@sk:	socket we are sending on
1176 *	@skb:	sk_buff containing the filled-in UDP header
1177 *		(checksum field must be zeroed out)
1178 *	@saddr: source address
1179 *	@daddr: destination address
1180 *	@len:	length of packet
1181 */
1182static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
1183				 const struct in6_addr *saddr,
1184				 const struct in6_addr *daddr, int len)
1185{
1186	unsigned int offset;
1187	struct udphdr *uh = udp_hdr(skb);
1188	struct sk_buff *frags = skb_shinfo(skb)->frag_list;
1189	__wsum csum = 0;
1190
1191	if (!frags) {
1192		/* Only one fragment on the socket.  */
1193		skb->csum_start = skb_transport_header(skb) - skb->head;
1194		skb->csum_offset = offsetof(struct udphdr, check);
1195		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1196	} else {
1197		/*
1198		 * HW-checksum won't work as there are two or more
1199		 * fragments on the socket so that all csums of sk_buffs
1200		 * should be together
1201		 */
1202		offset = skb_transport_offset(skb);
1203		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1204		csum = skb->csum;
1205
1206		skb->ip_summed = CHECKSUM_NONE;
1207
1208		do {
1209			csum = csum_add(csum, frags->csum);
1210		} while ((frags = frags->next));
1211
1212		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1213					    csum);
1214		if (uh->check == 0)
1215			uh->check = CSUM_MANGLED_0;
1216	}
1217}
1218
1219/*
1220 *	Sending
1221 */
1222
1223static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
1224			   struct inet_cork *cork)
1225{
1226	struct sock *sk = skb->sk;
1227	struct udphdr *uh;
 
 
 
1228	int err = 0;
1229	int is_udplite = IS_UDPLITE(sk);
1230	__wsum csum = 0;
1231	int offset = skb_transport_offset(skb);
1232	int len = skb->len - offset;
1233	int datalen = len - sizeof(*uh);
 
1234
1235	/*
1236	 * Create a UDP header
1237	 */
1238	uh = udp_hdr(skb);
1239	uh->source = fl6->fl6_sport;
1240	uh->dest = fl6->fl6_dport;
1241	uh->len = htons(len);
1242	uh->check = 0;
1243
1244	if (cork->gso_size) {
1245		const int hlen = skb_network_header_len(skb) +
1246				 sizeof(struct udphdr);
1247
1248		if (hlen + cork->gso_size > cork->fragsize) {
1249			kfree_skb(skb);
1250			return -EINVAL;
1251		}
1252		if (datalen > cork->gso_size * UDP_MAX_SEGMENTS) {
1253			kfree_skb(skb);
1254			return -EINVAL;
1255		}
1256		if (udp_sk(sk)->no_check6_tx) {
1257			kfree_skb(skb);
1258			return -EINVAL;
1259		}
1260		if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
1261		    dst_xfrm(skb_dst(skb))) {
1262			kfree_skb(skb);
1263			return -EIO;
1264		}
1265
1266		if (datalen > cork->gso_size) {
1267			skb_shinfo(skb)->gso_size = cork->gso_size;
1268			skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
1269			skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
1270								 cork->gso_size);
1271		}
1272		goto csum_partial;
1273	}
1274
1275	if (is_udplite)
1276		csum = udplite_csum(skb);
1277	else if (udp_sk(sk)->no_check6_tx) {   /* UDP csum disabled */
1278		skb->ip_summed = CHECKSUM_NONE;
1279		goto send;
1280	} else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1281csum_partial:
1282		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1283		goto send;
1284	} else
1285		csum = udp_csum(skb);
1286
1287	/* add protocol-dependent pseudo-header */
1288	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1289				    len, fl6->flowi6_proto, csum);
1290	if (uh->check == 0)
1291		uh->check = CSUM_MANGLED_0;
1292
1293send:
1294	err = ip6_send_skb(skb);
1295	if (err) {
1296		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1297			UDP6_INC_STATS(sock_net(sk),
1298				       UDP_MIB_SNDBUFERRORS, is_udplite);
1299			err = 0;
1300		}
1301	} else {
1302		UDP6_INC_STATS(sock_net(sk),
1303			       UDP_MIB_OUTDATAGRAMS, is_udplite);
1304	}
1305	return err;
1306}
1307
1308static int udp_v6_push_pending_frames(struct sock *sk)
1309{
1310	struct sk_buff *skb;
1311	struct udp_sock  *up = udp_sk(sk);
1312	int err = 0;
1313
1314	if (up->pending == AF_INET)
1315		return udp_push_pending_frames(sk);
1316
1317	skb = ip6_finish_skb(sk);
1318	if (!skb)
1319		goto out;
1320
1321	err = udp_v6_send_skb(skb, &inet_sk(sk)->cork.fl.u.ip6,
1322			      &inet_sk(sk)->cork.base);
1323out:
1324	up->len = 0;
1325	up->pending = 0;
1326	return err;
1327}
1328
1329int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
1330{
1331	struct ipv6_txoptions opt_space;
1332	struct udp_sock *up = udp_sk(sk);
1333	struct inet_sock *inet = inet_sk(sk);
1334	struct ipv6_pinfo *np = inet6_sk(sk);
1335	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1336	struct in6_addr *daddr, *final_p, final;
1337	struct ipv6_txoptions *opt = NULL;
1338	struct ipv6_txoptions *opt_to_free = NULL;
1339	struct ip6_flowlabel *flowlabel = NULL;
1340	struct inet_cork_full cork;
1341	struct flowi6 *fl6 = &cork.fl.u.ip6;
1342	struct dst_entry *dst;
1343	struct ipcm6_cookie ipc6;
1344	int addr_len = msg->msg_namelen;
1345	bool connected = false;
1346	int ulen = len;
1347	int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE;
 
 
 
1348	int err;
 
1349	int is_udplite = IS_UDPLITE(sk);
1350	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1351
1352	ipcm6_init(&ipc6);
1353	ipc6.gso_size = READ_ONCE(up->gso_size);
1354	ipc6.sockc.tsflags = sk->sk_tsflags;
1355	ipc6.sockc.mark = sk->sk_mark;
1356
1357	/* destination address check */
1358	if (sin6) {
1359		if (addr_len < offsetof(struct sockaddr, sa_data))
1360			return -EINVAL;
1361
1362		switch (sin6->sin6_family) {
1363		case AF_INET6:
1364			if (addr_len < SIN6_LEN_RFC2133)
1365				return -EINVAL;
1366			daddr = &sin6->sin6_addr;
1367			if (ipv6_addr_any(daddr) &&
1368			    ipv6_addr_v4mapped(&np->saddr))
1369				ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1370						       daddr);
1371			break;
1372		case AF_INET:
1373			goto do_udp_sendmsg;
1374		case AF_UNSPEC:
1375			msg->msg_name = sin6 = NULL;
1376			msg->msg_namelen = addr_len = 0;
1377			daddr = NULL;
1378			break;
1379		default:
1380			return -EINVAL;
1381		}
1382	} else if (!up->pending) {
1383		if (sk->sk_state != TCP_ESTABLISHED)
1384			return -EDESTADDRREQ;
1385		daddr = &sk->sk_v6_daddr;
1386	} else
1387		daddr = NULL;
1388
1389	if (daddr) {
1390		if (ipv6_addr_v4mapped(daddr)) {
1391			struct sockaddr_in sin;
1392			sin.sin_family = AF_INET;
1393			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1394			sin.sin_addr.s_addr = daddr->s6_addr32[3];
1395			msg->msg_name = &sin;
1396			msg->msg_namelen = sizeof(sin);
1397do_udp_sendmsg:
1398			if (ipv6_only_sock(sk))
1399				return -ENETUNREACH;
1400			return udp_sendmsg(sk, msg, len);
1401		}
1402	}
1403
 
 
 
1404	/* Rough check on arithmetic overflow,
1405	   better check is made in ip6_append_data().
1406	   */
1407	if (len > INT_MAX - sizeof(struct udphdr))
1408		return -EMSGSIZE;
1409
1410	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
1411	if (up->pending) {
1412		if (up->pending == AF_INET)
1413			return udp_sendmsg(sk, msg, len);
1414		/*
1415		 * There are pending frames.
1416		 * The socket lock must be held while it's corked.
1417		 */
1418		lock_sock(sk);
1419		if (likely(up->pending)) {
1420			if (unlikely(up->pending != AF_INET6)) {
1421				release_sock(sk);
1422				return -EAFNOSUPPORT;
1423			}
1424			dst = NULL;
1425			goto do_append_data;
1426		}
1427		release_sock(sk);
1428	}
1429	ulen += sizeof(struct udphdr);
1430
1431	memset(fl6, 0, sizeof(*fl6));
1432
1433	if (sin6) {
1434		if (sin6->sin6_port == 0)
1435			return -EINVAL;
1436
1437		fl6->fl6_dport = sin6->sin6_port;
1438		daddr = &sin6->sin6_addr;
1439
1440		if (np->sndflow) {
1441			fl6->flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1442			if (fl6->flowlabel & IPV6_FLOWLABEL_MASK) {
1443				flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
1444				if (IS_ERR(flowlabel))
1445					return -EINVAL;
 
1446			}
1447		}
1448
1449		/*
1450		 * Otherwise it will be difficult to maintain
1451		 * sk->sk_dst_cache.
1452		 */
1453		if (sk->sk_state == TCP_ESTABLISHED &&
1454		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1455			daddr = &sk->sk_v6_daddr;
1456
1457		if (addr_len >= sizeof(struct sockaddr_in6) &&
1458		    sin6->sin6_scope_id &&
1459		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1460			fl6->flowi6_oif = sin6->sin6_scope_id;
1461	} else {
1462		if (sk->sk_state != TCP_ESTABLISHED)
1463			return -EDESTADDRREQ;
1464
1465		fl6->fl6_dport = inet->inet_dport;
1466		daddr = &sk->sk_v6_daddr;
1467		fl6->flowlabel = np->flow_label;
1468		connected = true;
1469	}
1470
1471	if (!fl6->flowi6_oif)
1472		fl6->flowi6_oif = READ_ONCE(sk->sk_bound_dev_if);
1473
1474	if (!fl6->flowi6_oif)
1475		fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1476
1477	fl6->flowi6_uid = sk->sk_uid;
1478
1479	if (msg->msg_controllen) {
1480		opt = &opt_space;
1481		memset(opt, 0, sizeof(struct ipv6_txoptions));
1482		opt->tot_len = sizeof(*opt);
1483		ipc6.opt = opt;
1484
1485		err = udp_cmsg_send(sk, msg, &ipc6.gso_size);
1486		if (err > 0)
1487			err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, fl6,
1488						    &ipc6);
1489		if (err < 0) {
1490			fl6_sock_release(flowlabel);
1491			return err;
1492		}
1493		if ((fl6->flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1494			flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
1495			if (IS_ERR(flowlabel))
1496				return -EINVAL;
1497		}
1498		if (!(opt->opt_nflen|opt->opt_flen))
1499			opt = NULL;
1500		connected = false;
1501	}
1502	if (!opt) {
1503		opt = txopt_get(np);
1504		opt_to_free = opt;
1505	}
 
 
1506	if (flowlabel)
1507		opt = fl6_merge_options(&opt_space, flowlabel, opt);
1508	opt = ipv6_fixup_options(&opt_space, opt);
1509	ipc6.opt = opt;
1510
1511	fl6->flowi6_proto = sk->sk_protocol;
1512	fl6->flowi6_mark = ipc6.sockc.mark;
1513	fl6->daddr = *daddr;
1514	if (ipv6_addr_any(&fl6->saddr) && !ipv6_addr_any(&np->saddr))
1515		fl6->saddr = np->saddr;
1516	fl6->fl6_sport = inet->inet_sport;
1517
1518	if (cgroup_bpf_enabled(CGROUP_UDP6_SENDMSG) && !connected) {
1519		err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk,
1520					   (struct sockaddr *)sin6,
1521					   &fl6->saddr);
1522		if (err)
1523			goto out_no_dst;
1524		if (sin6) {
1525			if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
1526				/* BPF program rewrote IPv6-only by IPv4-mapped
1527				 * IPv6. It's currently unsupported.
1528				 */
1529				err = -ENOTSUPP;
1530				goto out_no_dst;
1531			}
1532			if (sin6->sin6_port == 0) {
1533				/* BPF program set invalid port. Reject it. */
1534				err = -EINVAL;
1535				goto out_no_dst;
1536			}
1537			fl6->fl6_dport = sin6->sin6_port;
1538			fl6->daddr = sin6->sin6_addr;
1539		}
1540	}
1541
1542	if (ipv6_addr_any(&fl6->daddr))
1543		fl6->daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1544
1545	final_p = fl6_update_dst(fl6, opt, &final);
1546	if (final_p)
1547		connected = false;
1548
1549	if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) {
1550		fl6->flowi6_oif = np->mcast_oif;
1551		connected = false;
1552	} else if (!fl6->flowi6_oif)
1553		fl6->flowi6_oif = np->ucast_oif;
1554
1555	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
1556
1557	if (ipc6.tclass < 0)
1558		ipc6.tclass = np->tclass;
1559
1560	fl6->flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6->flowlabel);
1561
1562	dst = ip6_sk_dst_lookup_flow(sk, fl6, final_p, connected);
1563	if (IS_ERR(dst)) {
1564		err = PTR_ERR(dst);
1565		dst = NULL;
1566		goto out;
1567	}
1568
1569	if (ipc6.hlimit < 0)
1570		ipc6.hlimit = ip6_sk_dst_hoplimit(np, fl6, dst);
 
 
 
 
 
 
 
 
 
 
 
 
1571
1572	if (msg->msg_flags&MSG_CONFIRM)
1573		goto do_confirm;
1574back_from_confirm:
1575
1576	/* Lockless fast path for the non-corking case */
1577	if (!corkreq) {
1578		struct sk_buff *skb;
1579
1580		skb = ip6_make_skb(sk, getfrag, msg, ulen,
1581				   sizeof(struct udphdr), &ipc6,
1582				   (struct rt6_info *)dst,
1583				   msg->msg_flags, &cork);
1584		err = PTR_ERR(skb);
1585		if (!IS_ERR_OR_NULL(skb))
1586			err = udp_v6_send_skb(skb, fl6, &cork.base);
1587		/* ip6_make_skb steals dst reference */
1588		goto out_no_dst;
1589	}
1590
1591	lock_sock(sk);
1592	if (unlikely(up->pending)) {
1593		/* The socket is already corked while preparing it. */
1594		/* ... which is an evident application bug. --ANK */
1595		release_sock(sk);
1596
1597		net_dbg_ratelimited("udp cork app bug 2\n");
1598		err = -EINVAL;
1599		goto out;
1600	}
1601
1602	up->pending = AF_INET6;
1603
1604do_append_data:
1605	if (ipc6.dontfrag < 0)
1606		ipc6.dontfrag = np->dontfrag;
1607	up->len += ulen;
1608	err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1609			      &ipc6, fl6, (struct rt6_info *)dst,
1610			      corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
 
 
1611	if (err)
1612		udp_v6_flush_pending_frames(sk);
1613	else if (!corkreq)
1614		err = udp_v6_push_pending_frames(sk);
1615	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1616		up->pending = 0;
1617
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1618	if (err > 0)
1619		err = np->recverr ? net_xmit_errno(err) : 0;
1620	release_sock(sk);
1621
1622out:
1623	dst_release(dst);
1624out_no_dst:
1625	fl6_sock_release(flowlabel);
1626	txopt_put(opt_to_free);
1627	if (!err)
1628		return len;
1629	/*
1630	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
1631	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1632	 * we don't have a good statistic (IpOutDiscards but it can be too many
1633	 * things).  We could add another new stat but at least for now that
1634	 * seems like overkill.
1635	 */
1636	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1637		UDP6_INC_STATS(sock_net(sk),
1638			       UDP_MIB_SNDBUFERRORS, is_udplite);
1639	}
1640	return err;
1641
1642do_confirm:
1643	if (msg->msg_flags & MSG_PROBE)
1644		dst_confirm_neigh(dst, &fl6->daddr);
1645	if (!(msg->msg_flags&MSG_PROBE) || len)
1646		goto back_from_confirm;
1647	err = 0;
1648	goto out;
1649}
1650EXPORT_SYMBOL(udpv6_sendmsg);
1651
1652void udpv6_destroy_sock(struct sock *sk)
1653{
1654	struct udp_sock *up = udp_sk(sk);
1655	lock_sock(sk);
1656
1657	/* protects from races with udp_abort() */
1658	sock_set_flag(sk, SOCK_DEAD);
1659	udp_v6_flush_pending_frames(sk);
1660	release_sock(sk);
1661
1662	if (static_branch_unlikely(&udpv6_encap_needed_key)) {
1663		if (up->encap_type) {
1664			void (*encap_destroy)(struct sock *sk);
1665			encap_destroy = READ_ONCE(up->encap_destroy);
1666			if (encap_destroy)
1667				encap_destroy(sk);
1668		}
1669		if (up->encap_enabled) {
1670			static_branch_dec(&udpv6_encap_needed_key);
1671			udp_encap_disable();
1672		}
1673	}
1674}
1675
1676/*
1677 *	Socket option code for UDP
1678 */
1679int udpv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1680		     unsigned int optlen)
1681{
1682	if (level == SOL_UDP  ||  level == SOL_UDPLITE || level == SOL_SOCKET)
1683		return udp_lib_setsockopt(sk, level, optname,
1684					  optval, optlen,
1685					  udp_v6_push_pending_frames);
1686	return ipv6_setsockopt(sk, level, optname, optval, optlen);
1687}
1688
 
 
 
 
 
 
 
 
 
 
 
1689int udpv6_getsockopt(struct sock *sk, int level, int optname,
1690		     char __user *optval, int __user *optlen)
1691{
1692	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
1693		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1694	return ipv6_getsockopt(sk, level, optname, optval, optlen);
1695}
1696
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1697static const struct inet6_protocol udpv6_protocol = {
1698	.handler	=	udpv6_rcv,
1699	.err_handler	=	udpv6_err,
 
 
1700	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1701};
1702
1703/* ------------------------------------------------------------------------ */
1704#ifdef CONFIG_PROC_FS
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1705int udp6_seq_show(struct seq_file *seq, void *v)
1706{
1707	if (v == SEQ_START_TOKEN) {
1708		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1709	} else {
1710		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1711		struct inet_sock *inet = inet_sk(v);
1712		__u16 srcp = ntohs(inet->inet_sport);
1713		__u16 destp = ntohs(inet->inet_dport);
1714		__ip6_dgram_sock_seq_show(seq, v, srcp, destp,
1715					  udp_rqueue_get(v), bucket);
1716	}
1717	return 0;
1718}
1719
1720const struct seq_operations udp6_seq_ops = {
1721	.start		= udp_seq_start,
1722	.next		= udp_seq_next,
1723	.stop		= udp_seq_stop,
1724	.show		= udp6_seq_show,
1725};
1726EXPORT_SYMBOL(udp6_seq_ops);
1727
1728static struct udp_seq_afinfo udp6_seq_afinfo = {
 
1729	.family		= AF_INET6,
1730	.udp_table	= NULL,
 
 
 
 
 
 
1731};
1732
1733int __net_init udp6_proc_init(struct net *net)
1734{
1735	if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops,
1736			sizeof(struct udp_iter_state), &udp6_seq_afinfo))
1737		return -ENOMEM;
1738	return 0;
1739}
1740
1741void udp6_proc_exit(struct net *net)
1742{
1743	remove_proc_entry("udp6", net->proc_net);
1744}
1745#endif /* CONFIG_PROC_FS */
1746
1747/* ------------------------------------------------------------------------ */
1748
1749struct proto udpv6_prot = {
1750	.name			= "UDPv6",
1751	.owner			= THIS_MODULE,
1752	.close			= udp_lib_close,
1753	.pre_connect		= udpv6_pre_connect,
1754	.connect		= ip6_datagram_connect,
1755	.disconnect		= udp_disconnect,
1756	.ioctl			= udp_ioctl,
1757	.init			= udpv6_init_sock,
1758	.destroy		= udpv6_destroy_sock,
1759	.setsockopt		= udpv6_setsockopt,
1760	.getsockopt		= udpv6_getsockopt,
1761	.sendmsg		= udpv6_sendmsg,
1762	.recvmsg		= udpv6_recvmsg,
1763	.release_cb		= ip6_datagram_release_cb,
1764	.hash			= udp_lib_hash,
1765	.unhash			= udp_lib_unhash,
1766	.rehash			= udp_v6_rehash,
1767	.get_port		= udp_v6_get_port,
1768	.put_port		= udp_lib_unhash,
1769#ifdef CONFIG_BPF_SYSCALL
1770	.psock_update_sk_prot	= udp_bpf_update_proto,
 
 
 
 
 
1771#endif
1772
1773	.memory_allocated	= &udp_memory_allocated,
1774	.per_cpu_fw_alloc	= &udp_memory_per_cpu_fw_alloc,
1775
1776	.sysctl_mem		= sysctl_udp_mem,
1777	.sysctl_wmem_offset     = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1778	.sysctl_rmem_offset     = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1779	.obj_size		= sizeof(struct udp6_sock),
1780	.h.udp_table		= NULL,
1781	.diag_destroy		= udp_abort,
1782};
1783
1784static struct inet_protosw udpv6_protosw = {
1785	.type =      SOCK_DGRAM,
1786	.protocol =  IPPROTO_UDP,
1787	.prot =      &udpv6_prot,
1788	.ops =       &inet6_dgram_ops,
 
1789	.flags =     INET_PROTOSW_PERMANENT,
1790};
 
1791
1792int __init udpv6_init(void)
1793{
1794	int ret;
1795
1796	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1797	if (ret)
1798		goto out;
1799
1800	ret = inet6_register_protosw(&udpv6_protosw);
1801	if (ret)
1802		goto out_udpv6_protocol;
1803out:
1804	return ret;
1805
1806out_udpv6_protocol:
1807	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1808	goto out;
1809}
1810
1811void udpv6_exit(void)
1812{
1813	inet6_unregister_protosw(&udpv6_protosw);
1814	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1815}