cregit-Linux how code gets into the kernel

Release 4.11 net/ipv6/udp.c

Directory: net/ipv6
/*
 *      UDP over IPv6
 *      Linux INET6 implementation
 *
 *      Authors:
 *      Pedro Roque             <roque@di.fc.ul.pt>
 *
 *      Based on linux/ipv4/udp.c
 *
 *      Fixes:
 *      Hideaki YOSHIFUJI       :       sin6_scope_id support
 *      YOSHIFUJI Hideaki @USAGI and:   Support IPV6_V6ONLY socket option, which
 *      Alexey Kuznetsov                allow both IPv4 and IPv6 sockets to bind
 *                                      a single port at the same time.
 *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
 *      YOSHIFUJI Hideaki @USAGI:       convert /proc/net/udp6 to seq_file.
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/in6.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/ipv6.h>
#include <linux/icmpv6.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/uaccess.h>

#include <net/addrconf.h>
#include <net/ndisc.h>
#include <net/protocol.h>
#include <net/transp_v6.h>
#include <net/ip6_route.h>
#include <net/raw.h>
#include <net/tcp_states.h>
#include <net/ip6_checksum.h>
#include <net/xfrm.h>
#include <net/inet6_hashtables.h>
#include <net/busy_poll.h>
#include <net/sock_reuseport.h>

#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <trace/events/skb.h>
#include "udp_impl.h"




static bool udp6_lib_exact_dif_match(struct net *net, struct sk_buff *skb)
{
#if defined(CONFIG_NET_L3_MASTER_DEV)
	if (!net->ipv4.sysctl_udp_l3mdev_accept &&
	    skb && ipv6_l3mdev_skb(IP6CB(skb)->flags))
		return true;
#endif
	return false;
}


Contributors
PersonTokensPropCommitsCommitProp
Robert Shearman51100.00%1100.00%


Total51100.00%1100.00%






static u32 udp6_ehashfn(const struct net *net,
			const struct in6_addr *laddr,
			const u16 lport,
			const struct in6_addr *faddr,
			const __be16 fport)
{
	static u32 udp6_ehash_secret __read_mostly;
	static u32 udp_ipv6_hash_secret __read_mostly;

	u32 lhash, fhash;

	net_get_random_once(&udp6_ehash_secret,
			    sizeof(udp6_ehash_secret));
	net_get_random_once(&udp_ipv6_hash_secret,
			    sizeof(udp_ipv6_hash_secret));

	lhash = (__force u32)laddr->s6_addr32[3];
	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);

	return __inet6_ehashfn(lhash, lport, fhash, fport,
			       udp_ipv6_hash_secret + net_hash_mix(net));
}


Contributors
PersonTokensPropCommitsCommitProp
Hannes Frederic Sowa10797.27%250.00%


Eric Dumazet21.82%125.00%


Vladislav Yasevich10.91%125.00%


Total110100.00%4100.00%






static u32 udp6_portaddr_hash(const struct net *net,
			      const struct in6_addr *addr6,
			      unsigned int port)
{
	unsigned int hash, mix = net_hash_mix(net);

	if (ipv6_addr_any(addr6))
		hash = jhash_1word(0, mix);
	else if (ipv6_addr_v4mapped(addr6))
		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
	else
		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);

	return hash ^ port;
}


Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet9898.99%375.00%


Brian Haley11.01%125.00%


Total99100.00%4100.00%






int udp_v6_get_port(struct sock *sk, unsigned short snum)
{
	unsigned int hash2_nulladdr =
		udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
	unsigned int hash2_partial =
		udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);

	/* precompute partial secondary hash */
	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
	return udp_lib_get_port(sk, snum, hash2_nulladdr);
}


Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet4767.14%327.27%


Linus Torvalds (pre-git)1724.29%436.36%


Arnaldo Carvalho de Melo45.71%218.18%


Pavel Emelyanov11.43%19.09%


Gerrit Renker11.43%19.09%


Total70100.00%11100.00%






static void udp_v6_rehash(struct sock *sk)
{
	u16 new_hash = udp6_portaddr_hash(sock_net(sk),
					  &sk->sk_v6_rcv_saddr,
					  inet_sk(sk)->inet_num);

	udp_lib_rehash(sk, new_hash);
}


Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet41100.00%2100.00%


Total41100.00%2100.00%






static int compute_score(struct sock *sk, struct net *net,
			 const struct in6_addr *saddr, __be16 sport,
			 const struct in6_addr *daddr, unsigned short hnum,
			 int dif, bool exact_dif)
{
	int score;
	struct inet_sock *inet;

	if (!net_eq(sock_net(sk), net) ||
	    udp_sk(sk)->udp_port_hash != hnum ||
	    sk->sk_family != PF_INET6)
		return -1;

	score = 0;
	inet = inet_sk(sk);

	if (inet->inet_dport) {
		if (inet->inet_dport != sport)
			return -1;
		score++;
	}

	if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
			return -1;
		score++;
	}

	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
			return -1;
		score++;
	}

	if (sk->sk_bound_dev_if || exact_dif) {
		if (sk->sk_bound_dev_if != dif)
			return -1;
		score++;
	}

	if (sk->sk_incoming_cpu == raw_smp_processor_id())
		score++;

	return score;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)10949.32%419.05%


Eric Dumazet5826.24%628.57%


Joe Perches198.60%14.76%


Hideaki Yoshifuji / 吉藤英明114.98%314.29%


Pavel Emelyanov83.62%14.76%


Robert Shearman52.26%14.76%


Arnaldo Carvalho de Melo31.36%14.76%


Xuemin Su31.36%14.76%


Balazs Scheidler20.90%14.76%


David S. Miller20.90%14.76%


Gerrit Renker10.45%14.76%


Total221100.00%21100.00%



/* called with rcu_read_lock() */



static struct sock *udp6_lib_lookup2(struct net *net,
		const struct in6_addr *saddr, __be16 sport,
		const struct in6_addr *daddr, unsigned int hnum, int dif,
		bool exact_dif, struct udp_hslot *hslot2,
		struct sk_buff *skb)
{
	struct sock *sk, *result;
	int score, badness, matches = 0, reuseport = 0;
	u32 hash = 0;

	result = NULL;
	badness = -1;
	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
		score = compute_score(sk, net, saddr, sport,
				      daddr, hnum, dif, exact_dif);
		if (score > badness) {
			reuseport = sk->sk_reuseport;
			if (reuseport) {
				hash = udp6_ehashfn(net, daddr, hnum,
						    saddr, sport);

				result = reuseport_select_sock(sk, hash, skb,
							sizeof(struct udphdr));
				if (result)
					return result;
				matches = 1;
			}
			result = sk;
			badness = score;
		} else if (score == badness && reuseport) {
			matches++;
			if (reciprocal_scale(hash, matches) == 0)
				result = sk;
			hash = next_pseudo_random32(hash);
		}
	}
	return result;
}


Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet11250.45%327.27%


Tom Herbert7332.88%19.09%


Craig Gallek2611.71%327.27%


Robert Shearman52.25%19.09%


Daniel Borkmann41.80%19.09%


Xuemin Su10.45%19.09%


Hannes Frederic Sowa10.45%19.09%


Total222100.00%11100.00%



/* rcu_read_lock() must be held */



struct sock *__udp6_lib_lookup(struct net *net,
				      const struct in6_addr *saddr, __be16 sport,
				      const struct in6_addr *daddr, __be16 dport,
				      int dif, struct udp_table *udptable,
				      struct sk_buff *skb)
{
	struct sock *sk, *result;
	unsigned short hnum = ntohs(dport);
	unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
	struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
	bool exact_dif = udp6_lib_exact_dif_match(net, skb);
	int score, badness, matches = 0, reuseport = 0;
	u32 hash = 0;

	if (hslot->count > 10) {
		hash2 = udp6_portaddr_hash(net, daddr, hnum);
		slot2 = hash2 & udptable->mask;
		hslot2 = &udptable->hash2[slot2];
		if (hslot->count < hslot2->count)
			goto begin;

		result = udp6_lib_lookup2(net, saddr, sport,
					  daddr, hnum, dif, exact_dif,
					  hslot2, skb);
		if (!result) {
			unsigned int old_slot2 = slot2;
			hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
			slot2 = hash2 & udptable->mask;
			/* avoid searching the same slot again. */
			if (unlikely(slot2 == old_slot2))
				return result;

			hslot2 = &udptable->hash2[slot2];
			if (hslot->count < hslot2->count)
				goto begin;

			result = udp6_lib_lookup2(net, saddr, sport,
						  daddr, hnum, dif,
						  exact_dif, hslot2,
						  skb);
		}
		return result;
	}
begin:
	result = NULL;
	badness = -1;
	sk_for_each_rcu(sk, &hslot->head) {
		score = compute_score(sk, net, saddr, sport, daddr, hnum, dif,
				      exact_dif);
		if (score > badness) {
			reuseport = sk->sk_reuseport;
			if (reuseport) {
				hash = udp6_ehashfn(net, daddr, hnum,
						    saddr, sport);
				result = reuseport_select_sock(sk, hash, skb,
							sizeof(struct udphdr));
				if (result)
					return result;
				matches = 1;
			}
			result = sk;
			badness = score;
		} else if (score == badness && reuseport) {
			matches++;
			if (reciprocal_scale(hash, matches) == 0)
				result = sk;
			hash = next_pseudo_random32(hash);
		}
	}
	return result;
}

Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet27962.98%635.29%


Tom Herbert7216.25%15.88%


Craig Gallek296.55%317.65%


Xuemin Su214.74%15.88%


Linus Torvalds (pre-git)184.06%15.88%


Robert Shearman163.61%15.88%


Daniel Borkmann40.90%15.88%


Balazs Scheidler20.45%15.88%


Jorge Boncompte10.23%15.88%


Hannes Frederic Sowa10.23%15.88%


Total443100.00%17100.00%




EXPORT_SYMBOL_GPL(__udp6_lib_lookup);




static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
					  __be16 sport, __be16 dport,
					  struct udp_table *udptable)
{
	const struct ipv6hdr *iph = ipv6_hdr(skb);
	struct sock *sk;

	sk = skb_steal_sock(skb);
	if (unlikely(sk))
		return sk;
	return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
				 &iph->daddr, dport, inet6_iif(skb),
				 udptable, skb);
}


Contributors
PersonTokensPropCommitsCommitProp
KOVACS Krisztian7582.42%228.57%


Ian Morris66.59%114.29%


Alexander Duyck55.49%114.29%


Eric Dumazet33.30%228.57%


Craig Gallek22.20%114.29%


Total91100.00%7100.00%






struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
				 __be16 sport, __be16 dport)
{
	const struct ipv6hdr *iph = ipv6_hdr(skb);

	return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
				 &iph->daddr, dport, inet6_iif(skb),
				 &udp_table, skb);
}

Contributors
PersonTokensPropCommitsCommitProp
Tom Herbert6296.88%150.00%


Alexander Duyck23.12%150.00%


Total64100.00%2100.00%




EXPORT_SYMBOL_GPL(udp6_lib_lookup_skb);

/* Must be called under rcu_read_lock().
 * Does increment socket refcount.
 */
#if IS_ENABLED(CONFIG_NETFILTER_XT_MATCH_SOCKET) || \
    IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TPROXY) || \
    IS_ENABLED(CONFIG_NF_SOCKET_IPV6)



struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
			     const struct in6_addr *daddr, __be16 dport, int dif)
{
	struct sock *sk;

	sk =  __udp6_lib_lookup(net, saddr, sport, daddr, dport,
				dif, &udp_table, NULL);
	if (sk && !atomic_inc_not_zero(&sk->sk_refcnt))
		sk = NULL;
	return sk;
}

Contributors
PersonTokensPropCommitsCommitProp
Balazs Scheidler4758.75%133.33%


Eric Dumazet3138.75%133.33%


Craig Gallek22.50%133.33%


Total80100.00%3100.00%




EXPORT_SYMBOL_GPL(udp6_lib_lookup);
#endif

/*
 *      This should be easy, if there is something there we
 *      return it, otherwise we block.
 */




int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
		  int noblock, int flags, int *addr_len)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct inet_sock *inet = inet_sk(sk);
	struct sk_buff *skb;
	unsigned int ulen, copied;
	int peeked, peeking, off;
	int err;
	int is_udplite = IS_UDPLITE(sk);
	bool checksum_valid = false;
	int is_udp4;

	if (flags & MSG_ERRQUEUE)
		return ipv6_recv_error(sk, msg, len, addr_len);

	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);

try_again:
	peeking = off = sk_peek_offset(sk, flags);
	skb = __skb_recv_udp(sk, flags, noblock, &peeked, &off, &err);
	if (!skb)
		return err;

	ulen = skb->len;
	copied = len;
	if (copied > ulen - off)
		copied = ulen - off;
	else if (copied < ulen)
		msg->msg_flags |= MSG_TRUNC;

	is_udp4 = (skb->protocol == htons(ETH_P_IP));

	/*
         * If checksum is needed at all, try to do it while copying the
         * data.  If the data is truncated, or if we only want a partial
         * coverage checksum (UDP-Lite), do it before the copy.
         */

	if (copied < ulen || peeking ||
	    (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
		checksum_valid = !udp_lib_checksum_complete(skb);
		if (!checksum_valid)
			goto csum_copy_err;
	}

	if (checksum_valid || skb_csum_unnecessary(skb))
		err = skb_copy_datagram_msg(skb, off, msg, copied);
	else {
		err = skb_copy_and_csum_datagram_msg(skb, off, msg);
		if (err == -EINVAL)
			goto csum_copy_err;
	}
	if (unlikely(err)) {
		if (!peeked) {
			atomic_inc(&sk->sk_drops);
			if (is_udp4)
				UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
					      is_udplite);
			else
				UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
					       is_udplite);
		}
		kfree_skb(skb);
		return err;
	}
	if (!peeked) {
		if (is_udp4)
			UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
				      is_udplite);
		else
			UDP6_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
				       is_udplite);
	}

	sock_recv_ts_and_drops(msg, sk, skb);

	/* Copy the address. */
	if (msg->msg_name) {
		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
		sin6->sin6_family = AF_INET6;
		sin6->sin6_port = udp_hdr(skb)->source;
		sin6->sin6_flowinfo = 0;

		if (is_udp4) {
			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
					       &sin6->sin6_addr);
			sin6->sin6_scope_id = 0;
		} else {
			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
			sin6->sin6_scope_id =
				ipv6_iface_scope_id(&sin6->sin6_addr,
						    inet6_iif(skb));
		}
		*addr_len = sizeof(*sin6);
	}

	if (np->rxopt.all)
		ip6_datagram_recv_common_ctl(sk, msg, skb);

	if (is_udp4) {
		if (inet->cmsg_flags)
			ip_cmsg_recv_offset(msg, sk, skb,
					    sizeof(struct udphdr), off);
	} else {
		if (np->rxopt.all)
			ip6_datagram_recv_specific_ctl(sk, msg, skb);
	}

	err = copied;
	if (flags & MSG_TRUNC)
		err = ulen;

	skb_consume_udp(sk, skb, peeking ? -err : err);
	return err;

csum_copy_err:
	if (!__sk_queue_drop_skb(sk, skb, flags, udp_skb_destructor)) {
		if (is_udp4) {
			UDP_INC_STATS(sock_net(sk),
				      UDP_MIB_CSUMERRORS, is_udplite);
			UDP_INC_STATS(sock_net(sk),
				      UDP_MIB_INERRORS, is_udplite);
		} else {
			UDP6_INC_STATS(sock_net(sk),
				       UDP_MIB_CSUMERRORS, is_udplite);
			UDP6_INC_STATS(sock_net(sk),
				       UDP_MIB_INERRORS, is_udplite);
		}
	}
	kfree_skb(skb);

	/* starting over for a new packet, but check if we need to yield */
	cond_resched();
	msg->msg_flags &= ~MSG_TRUNC;
	goto try_again;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)21630.29%1016.95%


Eric Dumazet11716.41%915.25%


Wei Yongjun547.57%23.39%


Herbert Xu496.87%58.47%


Hideaki Yoshifuji / 吉藤英明496.87%23.39%


Hannes Frederic Sowa466.45%46.78%


samanthakumar365.05%11.69%


Brian Haley304.21%23.39%


David S. Miller294.07%46.78%


Pavel Emelyanov152.10%23.39%


Gerrit Renker111.54%11.69%


Paolo Abeni91.26%35.08%


Arnaldo Carvalho de Melo91.26%35.08%


Samuel Thibault91.26%11.69%


Xufeng Zhang70.98%11.69%


Wang Chen60.84%11.69%


Steffen Hurrle60.84%11.69%


Linus Torvalds50.70%11.69%


Stephen Hemminger30.42%11.69%


Hideo Aoki30.42%11.69%


Duan Jiong10.14%11.69%


Neil Horman10.14%11.69%


Alexey Dobriyan10.14%11.69%


Al Viro10.14%11.69%


Total713100.00%59100.00%






void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
		    u8 type, u8 code, int offset, __be32 info,
		    struct udp_table *udptable)
{
	struct ipv6_pinfo *np;
	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
	const struct in6_addr *saddr = &hdr->saddr;
	const struct in6_addr *daddr = &hdr->daddr;
	struct udphdr *uh = (struct udphdr *)(skb->data+offset);
	struct sock *sk;
	int harderr;
	int err;
	struct net *net = dev_net(skb->dev);

	sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
			       inet6_iif(skb), udptable, skb);
	if (!sk) {
		__ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
				  ICMP6_MIB_INERRORS);
		return;
	}

	harderr = icmpv6_err_convert(type, code, &err);
	np = inet6_sk(sk);

	if (type == ICMPV6_PKT_TOOBIG) {
		if (!ip6_sk_accept_pmtu(sk))
			goto out;
		ip6_sk_update_pmtu(skb, sk, info);
		if (np->pmtudisc != IPV6_PMTUDISC_DONT)
			harderr = 1;
	}
	if (type == NDISC_REDIRECT) {
		ip6_sk_redirect(skb, sk);
		goto out;
	}

	if (!np->recverr) {
		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
			goto out;
	} else {
		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
	}

	sk->sk_err = err;
	sk->sk_error_report(sk);
out:
	return;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)12640.26%725.00%


Wei Wang4213.42%13.57%


David S. Miller3410.86%310.71%


Linus Torvalds3310.54%13.57%


Duan Jiong319.90%27.14%


Hannes Frederic Sowa134.15%13.57%


Eric Dumazet82.56%414.29%


Hideaki Yoshifuji / 吉藤英明72.24%27.14%


Gerrit Renker61.92%13.57%


Pavel Emelyanov41.28%13.57%


Arnaldo Carvalho de Melo30.96%13.57%


Brian Haley20.64%13.57%


Craig Gallek20.64%13.57%


Ian Morris10.32%13.57%


Al Viro10.32%13.57%


Total313100.00%28100.00%






int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
	int rc;

	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
		sock_rps_save_rxhash(sk, skb);
		sk_mark_napi_id(sk, skb);
		sk_incoming_cpu_update(sk);
	} else {
		sk_mark_napi_id_once(sk, skb);
	}

	rc = __udp_enqueue_schedule_skb(sk, skb);
	if (rc < 0) {
		int is_udplite = IS_UDPLITE(sk);

		/* Note that an ENOMEM error is charged twice */
		if (rc == -ENOMEM)
			UDP6_INC_STATS(sock_net(sk),
					 UDP_MIB_RCVBUFERRORS, is_udplite);
		UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
		kfree_skb(skb);
		return -1;
	}

	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Benjamin LaHaise10178.29%114.29%


Eric Dumazet1813.95%457.14%


Shawn Bohrer96.98%114.29%


Paolo Abeni10.78%114.29%


Total129100.00%7100.00%






static __inline__ void udpv6_err(struct sk_buff *skb,
				 struct inet6_skb_parm *opt, u8 type,
				 u8 code, int offset, __be32 info)
{
	__udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
}


Contributors
PersonTokensPropCommitsCommitProp
Gerrit Renker4085.11%116.67%


Eric Dumazet24.26%116.67%


Brian Haley24.26%116.67%


Linus Torvalds (pre-git)12.13%116.67%


Al Viro12.13%116.67%


Hideaki Yoshifuji / 吉藤英明12.13%116.67%


Total47100.00%6100.00%




static struct static_key udpv6_encap_needed __read_mostly;



void udpv6_encap_enable(void)
{
	if (!static_key_enabled(&udpv6_encap_needed))
		static_key_slow_inc(&udpv6_encap_needed);
}

Contributors
PersonTokensPropCommitsCommitProp
Benjamin LaHaise22100.00%1100.00%


Total22100.00%1100.00%




EXPORT_SYMBOL(udpv6_encap_enable);




int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
	struct udp_sock *up = udp_sk(sk);
	int is_udplite = IS_UDPLITE(sk);

	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
		goto drop;

	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);

		/*
                 * This is an encapsulation socket so pass the skb to
                 * the socket's udp_encap_rcv() hook. Otherwise, just
                 * fall through and pass this up the UDP socket.
                 * up->encap_rcv() returns the following value:
                 * =0 if skb was successfully passed to the encap
                 *    handler or was discarded by it.
                 * >0 if skb should be passed on to UDP.
                 * <0 if skb should be resubmitted as proto -N
                 */

		/* if we're overly short, let UDP handle it */
		encap_rcv = ACCESS_ONCE(up->encap_rcv);
		if (encap_rcv) {
			int ret;

			/* Verify checksum before giving to encap */
			if (udp_lib_checksum_complete(skb))
				goto csum_error;

			ret = encap_rcv(sk, skb);
			if (ret <= 0) {
				__UDP_INC_STATS(sock_net(sk),
						UDP_MIB_INDATAGRAMS,
						is_udplite);
				return -