cregit-Linux how code gets into the kernel

Release 4.11 net/ipv4/udp.c

Directory: net/ipv4
/*
 * INET         An implementation of the TCP/IP protocol suite for the LINUX
 *              operating system.  INET is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              The User Datagram Protocol (UDP).
 *
 * Authors:     Ross Biro
 *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *              Arnt Gulbrandsen, <agulbra@nvg.unit.no>
 *              Alan Cox, <alan@lxorguk.ukuu.org.uk>
 *              Hirokazu Takahashi, <taka@valinux.co.jp>
 *
 * Fixes:
 *              Alan Cox        :       verify_area() calls
 *              Alan Cox        :       stopped close while in use off icmp
 *                                      messages. Not a fix but a botch that
 *                                      for udp at least is 'valid'.
 *              Alan Cox        :       Fixed icmp handling properly
 *              Alan Cox        :       Correct error for oversized datagrams
 *              Alan Cox        :       Tidied select() semantics.
 *              Alan Cox        :       udp_err() fixed properly, also now
 *                                      select and read wake correctly on errors
 *              Alan Cox        :       udp_send verify_area moved to avoid mem leak
 *              Alan Cox        :       UDP can count its memory
 *              Alan Cox        :       send to an unknown connection causes
 *                                      an ECONNREFUSED off the icmp, but
 *                                      does NOT close.
 *              Alan Cox        :       Switched to new sk_buff handlers. No more backlog!
 *              Alan Cox        :       Using generic datagram code. Even smaller and the PEEK
 *                                      bug no longer crashes it.
 *              Fred Van Kempen :       Net2e support for sk->broadcast.
 *              Alan Cox        :       Uses skb_free_datagram
 *              Alan Cox        :       Added get/set sockopt support.
 *              Alan Cox        :       Broadcasting without option set returns EACCES.
 *              Alan Cox        :       No wakeup calls. Instead we now use the callbacks.
 *              Alan Cox        :       Use ip_tos and ip_ttl
 *              Alan Cox        :       SNMP Mibs
 *              Alan Cox        :       MSG_DONTROUTE, and 0.0.0.0 support.
 *              Matt Dillon     :       UDP length checks.
 *              Alan Cox        :       Smarter af_inet used properly.
 *              Alan Cox        :       Use new kernel side addressing.
 *              Alan Cox        :       Incorrect return on truncated datagram receive.
 *      Arnt Gulbrandsen        :       New udp_send and stuff
 *              Alan Cox        :       Cache last socket
 *              Alan Cox        :       Route cache
 *              Jon Peatfield   :       Minor efficiency fix to sendto().
 *              Mike Shaver     :       RFC1122 checks.
 *              Alan Cox        :       Nonblocking error fix.
 *      Willy Konynenberg       :       Transparent proxying support.
 *              Mike McLagan    :       Routing by source
 *              David S. Miller :       New socket lookup architecture.
 *                                      Last socket cache retained as it
 *                                      does have a high hit rate.
 *              Olaf Kirch      :       Don't linearise iovec on sendmsg.
 *              Andi Kleen      :       Some cleanups, cache destination entry
 *                                      for connect.
 *      Vitaly E. Lavrov        :       Transparent proxy revived after year coma.
 *              Melvin Smith    :       Check msg_name not msg_namelen in sendto(),
 *                                      return ENOTCONN for unconnected sockets (POSIX)
 *              Janos Farkas    :       don't deliver multi/broadcasts to a different
 *                                      bound-to-device socket
 *      Hirokazu Takahashi      :       HW checksumming for outgoing UDP
 *                                      datagrams.
 *      Hirokazu Takahashi      :       sendfile() on UDP works now.
 *              Arnaldo C. Melo :       convert /proc/net/udp to seq_file
 *      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.
 *      Derek Atkins <derek@ihtfp.com>: Add Encapulation Support
 *      James Chapman           :       Add L2TP encapsulation type.
 *
 *
 *              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.
 */


#define pr_fmt(fmt) "UDP: " fmt

#include <linux/uaccess.h>
#include <asm/ioctls.h>
#include <linux/bootmem.h>
#include <linux/highmem.h>
#include <linux/swap.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/module.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/igmp.h>
#include <linux/inetdevice.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/slab.h>
#include <net/tcp_states.h>
#include <linux/skbuff.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <net/net_namespace.h>
#include <net/icmp.h>
#include <net/inet_hashtables.h>
#include <net/route.h>
#include <net/checksum.h>
#include <net/xfrm.h>
#include <trace/events/udp.h>
#include <linux/static_key.h>
#include <trace/events/skb.h>
#include <net/busy_poll.h>
#include "udp_impl.h"
#include <net/sock_reuseport.h>
#include <net/addrconf.h>


struct udp_table udp_table __read_mostly;

EXPORT_SYMBOL(udp_table);


long sysctl_udp_mem[3] __read_mostly;

EXPORT_SYMBOL(sysctl_udp_mem);


int sysctl_udp_rmem_min __read_mostly;

EXPORT_SYMBOL(sysctl_udp_rmem_min);


int sysctl_udp_wmem_min __read_mostly;

EXPORT_SYMBOL(sysctl_udp_wmem_min);


atomic_long_t udp_memory_allocated;

EXPORT_SYMBOL(udp_memory_allocated);


#define MAX_UDP_PORTS 65536

#define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN)

/* IPCB reference means this can not be used from early demux */



static bool udp_lib_exact_dif_match(struct net *net, struct sk_buff *skb)
{
#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
	if (!net->ipv4.sysctl_udp_l3mdev_accept &&
	    skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
		return true;
#endif
	return false;
}


Contributors
PersonTokensPropCommitsCommitProp
Robert Shearman51100.00%1100.00%


Total51100.00%1100.00%






static int udp_lib_lport_inuse(struct net *net, __u16 num,
			       const struct udp_hslot *hslot,
			       unsigned long *bitmap,
			       struct sock *sk, unsigned int log)
{
	struct sock *sk2;
	kuid_t uid = sock_i_uid(sk);

	sk_for_each(sk2, &hslot->head) {
		if (net_eq(sock_net(sk2), net) &&
		    sk2 != sk &&
		    (bitmap || udp_sk(sk2)->udp_port_hash == num) &&
		    (!sk2->sk_reuse || !sk->sk_reuse) &&
		    (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
		     sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
		    inet_rcv_saddr_equal(sk, sk2, true)) {
			if (sk2->sk_reuseport && sk->sk_reuseport &&
			    !rcu_access_pointer(sk->sk_reuseport_cb) &&
			    uid_eq(uid, sock_i_uid(sk2))) {
				if (!bitmap)
					return 0;
			} else {
				if (!bitmap)
					return 1;
				__set_bit(udp_sk(sk2)->udp_port_hash >> log,
					  bitmap);
			}
		}
	}
	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet8845.60%628.57%


Eric Garver2713.99%14.76%


Tom Herbert2311.92%14.76%


Gerrit Renker199.84%29.52%


Pavel Emelyanov94.66%14.76%


Hideaki Yoshifuji / 吉藤英明73.63%29.52%


Craig Gallek63.11%14.76%


Joe Perches63.11%14.76%


David S. Miller31.55%29.52%


Linus Torvalds (pre-git)21.04%14.76%


Al Viro10.52%14.76%


Stephen Hemminger10.52%14.76%


Josef Bacik10.52%14.76%


Total193100.00%21100.00%



/*
 * Note: we still hold spinlock of primary hash chain, so no other writer
 * can insert/delete a socket with local_port == num
 */



static int udp_lib_lport_inuse2(struct net *net, __u16 num,
				struct udp_hslot *hslot2,
				struct sock *sk)
{
	struct sock *sk2;
	kuid_t uid = sock_i_uid(sk);
	int res = 0;

	spin_lock(&hslot2->lock);
	udp_portaddr_for_each_entry(sk2, &hslot2->head) {
		if (net_eq(sock_net(sk2), net) &&
		    sk2 != sk &&
		    (udp_sk(sk2)->udp_port_hash == num) &&
		    (!sk2->sk_reuse || !sk->sk_reuse) &&
		    (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
		     sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
		    inet_rcv_saddr_equal(sk, sk2, true)) {
			if (sk2->sk_reuseport && sk->sk_reuseport &&
			    !rcu_access_pointer(sk->sk_reuseport_cb) &&
			    uid_eq(uid, sock_i_uid(sk2))) {
				res = 0;
			} else {
				res = 1;
			}
			break;
		}
	}
	spin_unlock(&hslot2->lock);
	return res;
}


Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet12669.61%116.67%


Eric Garver2312.71%116.67%


Tom Herbert2312.71%116.67%


Craig Gallek63.31%116.67%


Joe Perches21.10%116.67%


Josef Bacik10.55%116.67%


Total181100.00%6100.00%






static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot)
{
	struct net *net = sock_net(sk);
	kuid_t uid = sock_i_uid(sk);
	struct sock *sk2;

	sk_for_each(sk2, &hslot->head) {
		if (net_eq(sock_net(sk2), net) &&
		    sk2 != sk &&
		    sk2->sk_family == sk->sk_family &&
		    ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
		    (udp_sk(sk2)->udp_port_hash == udp_sk(sk)->udp_port_hash) &&
		    (sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
		    sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
		    inet_rcv_saddr_equal(sk, sk2, false)) {
			return reuseport_add_sock(sk, sk2);
		}
	}

	/* Initial allocation may have already happened via setsockopt */
	if (!rcu_access_pointer(sk->sk_reuseport_cb))
		return reuseport_alloc(sk);
	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Craig Gallek15898.75%133.33%


Josef Bacik10.62%133.33%


Eric Dumazet10.62%133.33%


Total160100.00%3100.00%



/**
 *  udp_lib_get_port  -  UDP/-Lite port lookup for IPv4 and IPv6
 *
 *  @sk:          socket struct in question
 *  @snum:        port number to look up
 *  @hash2_nulladdr: AF-dependent hash value in secondary hash chains,
 *                   with NULL address
 */



int udp_lib_get_port(struct sock *sk, unsigned short snum,
		     unsigned int hash2_nulladdr)
{
	struct udp_hslot *hslot, *hslot2;
	struct udp_table *udptable = sk->sk_prot->h.udp_table;
	int    error = 1;
	struct net *net = sock_net(sk);

	if (!snum) {
		int low, high, remaining;
		unsigned int rand;
		unsigned short first, last;
		DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN);

		inet_get_local_port_range(net, &low, &high);
		remaining = (high - low) + 1;

		rand = prandom_u32();
		first = reciprocal_scale(rand, remaining) + low;
		/*
                 * force rand to be an odd multiple of UDP_HTABLE_SIZE
                 */
		rand = (rand | 1) * (udptable->mask + 1);
		last = first + udptable->mask + 1;
		do {
			hslot = udp_hashslot(udptable, net, first);
			bitmap_zero(bitmap, PORTS_PER_CHAIN);
			spin_lock_bh(&hslot->lock);
			udp_lib_lport_inuse(net, snum, hslot, bitmap, sk,
					    udptable->log);

			snum = first;
			/*
                         * Iterate on all possible values of snum for this hash.
                         * Using steps of an odd multiple of UDP_HTABLE_SIZE
                         * give us randomization and full range coverage.
                         */
			do {
				if (low <= snum && snum <= high &&
				    !test_bit(snum >> udptable->log, bitmap) &&
				    !inet_is_local_reserved_port(net, snum))
					goto found;
				snum += rand;
			} while (snum != first);
			spin_unlock_bh(&hslot->lock);
			cond_resched();
		} while (++first != last);
		goto fail;
	} else {
		hslot = udp_hashslot(udptable, net, snum);
		spin_lock_bh(&hslot->lock);
		if (hslot->count > 10) {
			int exist;
			unsigned int slot2 = udp_sk(sk)->udp_portaddr_hash ^ snum;

			slot2          &= udptable->mask;
			hash2_nulladdr &= udptable->mask;

			hslot2 = udp_hashslot2(udptable, slot2);
			if (hslot->count < hslot2->count)
				goto scan_primary_hash;

			exist = udp_lib_lport_inuse2(net, snum, hslot2, sk);
			if (!exist && (hash2_nulladdr != slot2)) {
				hslot2 = udp_hashslot2(udptable, hash2_nulladdr);
				exist = udp_lib_lport_inuse2(net, snum, hslot2,
							     sk);
			}
			if (exist)
				goto fail_unlock;
			else
				goto found;
		}
scan_primary_hash:
		if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk, 0))
			goto fail_unlock;
	}
found:
	inet_sk(sk)->inet_num = snum;
	udp_sk(sk)->udp_port_hash = snum;
	udp_sk(sk)->udp_portaddr_hash ^= snum;
	if (sk_unhashed(sk)) {
		if (sk->sk_reuseport &&
		    udp_reuseport_add_sock(sk, hslot)) {
			inet_sk(sk)->inet_num = 0;
			udp_sk(sk)->udp_port_hash = 0;
			udp_sk(sk)->udp_portaddr_hash ^= snum;
			goto fail_unlock;
		}

		sk_add_node_rcu(sk, &hslot->head);
		hslot->count++;
		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);

		hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
		spin_lock(&hslot2->lock);
		if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
		    sk->sk_family == AF_INET6)
			hlist_add_tail_rcu(&udp_sk(sk)->udp_portaddr_node,
					   &hslot2->head);
		else
			hlist_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
					   &hslot2->head);
		hslot2->count++;
		spin_unlock(&hslot2->lock);
	}
	sock_set_flag(sk, SOCK_RCU_FREE);
	error = 0;
fail_unlock:
	spin_unlock_bh(&hslot->lock);
fail:
	return error;
}

Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet40661.98%1530.61%


Craig Gallek7811.91%24.08%


Linus Torvalds (pre-git)507.63%816.33%


Pavel Emelyanov284.27%510.20%


Stephen Hemminger253.82%24.08%


Gerrit Renker172.60%12.04%


Anton Arapov131.98%12.04%


Américo Wang81.22%24.08%


Arnaldo Carvalho de Melo71.07%24.08%


David S. Miller60.92%48.16%


Daniel Borkmann40.61%12.04%


Hideaki Yoshifuji / 吉藤英明40.61%24.08%


Linus Torvalds30.46%12.04%


Eric Garver30.46%12.04%


Eric W. Biedermann20.31%12.04%


Aruna-Hewapathirane10.15%12.04%


Total655100.00%49100.00%




EXPORT_SYMBOL(udp_lib_get_port);




static u32 udp4_portaddr_hash(const struct net *net, __be32 saddr,
			      unsigned int port)
{
	return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port;
}


Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet36100.00%3100.00%


Total36100.00%3100.00%






int udp_v4_get_port(struct sock *sk, unsigned short snum)
{
	unsigned int hash2_nulladdr =
		udp4_portaddr_hash(sock_net(sk), htonl(INADDR_ANY), snum);
	unsigned int hash2_partial =
		udp4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_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 Dumazet5168.92%342.86%


David S. Miller1925.68%114.29%


Linus Torvalds (pre-git)22.70%114.29%


Pavel Emelyanov11.35%114.29%


Gerrit Renker11.35%114.29%


Total74100.00%7100.00%






static int compute_score(struct sock *sk, struct net *net,
			 __be32 saddr, __be16 sport,
			 __be32 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 ||
	    ipv6_only_sock(sk))
		return -1;

	score = (sk->sk_family == PF_INET) ? 2 : 1;
	inet = inet_sk(sk);

	if (inet->inet_rcv_saddr) {
		if (inet->inet_rcv_saddr != daddr)
			return -1;
		score += 4;
	}

	if (inet->inet_daddr) {
		if (inet->inet_daddr != saddr)
			return -1;
		score += 4;
	}

	if (inet->inet_dport) {
		if (inet->inet_dport != sport)
			return -1;
		score += 4;
	}

	if (sk->sk_bound_dev_if || exact_dif) {
		if (sk->sk_bound_dev_if != dif)
			return -1;
		score += 4;
	}
	if (sk->sk_incoming_cpu == raw_smp_processor_id())
		score++;
	return score;
}


Contributors
PersonTokensPropCommitsCommitProp
David S. Miller10751.44%16.67%


Eric Dumazet5024.04%426.67%


Joe Perches2110.10%16.67%


Hideaki Yoshifuji / 吉藤英明83.85%320.00%


Tom Herbert62.88%16.67%


Linus Torvalds (pre-git)62.88%16.67%


Robert Shearman52.40%16.67%


Xuemin Su31.44%16.67%


Gerrit Renker10.48%16.67%


Pavel Emelyanov10.48%16.67%


Total208100.00%15100.00%






static u32 udp_ehashfn(const struct net *net, const __be32 laddr,
		       const __u16 lport, const __be32 faddr,
		       const __be16 fport)
{
	static u32 udp_ehash_secret __read_mostly;

	net_get_random_once(&udp_ehash_secret, sizeof(udp_ehash_secret));

	return __inet_ehashfn(laddr, lport, faddr, fport,
			      udp_ehash_secret + net_hash_mix(net));
}


Contributors
PersonTokensPropCommitsCommitProp
Hannes Frederic Sowa6196.83%266.67%


Eric Dumazet23.17%133.33%


Total63100.00%3100.00%



/* called with rcu_read_lock() */



static struct sock *udp4_lib_lookup2(struct net *net,
		__be32 saddr, __be16 sport,
		__be32 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 = 0;
	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 = udp_ehashfn(net, daddr, hnum,
						   saddr, sport);
				result = reuseport_select_sock(sk, hash, skb,
							sizeof(struct udphdr));
				if (result)
					return result;
				matches = 1;
			}
			badness = score;
			result = sk;
		} else if (score == badness && reuseport) {
			matches++;
			if (reciprocal_scale(hash, matches) == 0)
				result = sk;
			hash = next_pseudo_random32(hash);
		}
	}
	return result;
}


Contributors
PersonTokensPropCommitsCommitProp
Eric Dumazet11051.16%327.27%


Tom Herbert6831.63%19.09%


Craig Gallek2612.09%327.27%


Robert Shearman52.33%19.09%


Daniel Borkmann41.86%19.09%


Hannes Frederic Sowa10.47%19.09%


Xuemin Su10.47%19.09%


Total215100.00%11100.00%



/* UDP is nearly always wildcards out the wazoo, it makes no sense to try
 * harder than this. -DaveM
 */



struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
		__be16 sport, __be32 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 = udp_lib_exact_dif_match(net, skb);
	int score, badness, matches = 0, reuseport = 0;
	u32 hash = 0;

	if (hslot->count > 10) {
		hash2 = udp4_portaddr_hash(net, daddr, hnum);
		slot2 = hash2 & udptable->mask;
		hslot2 = &udptable->hash2[slot2];
		if (hslot->count < hslot2->count)
			goto begin;

		result = udp4_lib_lookup2(net, saddr, sport,
					  daddr, hnum, dif,
					  exact_dif, hslot2, skb);
		if (!result) {
			unsigned int old_slot2 = slot2;
			hash2 = udp4_portaddr_hash(net, htonl(INADDR_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 = udp4_lib_lookup2(net, saddr, sport,
						  daddr, hnum, dif,
						  exact_dif, hslot2, skb);
		}
		return result;
	}
begin:
	result = NULL;
	badness = 0;
	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 = udp_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 Dumazet27863.47%741.18%


Tom Herbert7316.67%15.88%


Craig Gallek296.62%317.65%


Xuemin Su214.79%15.88%


Robert Shearman163.65%15.88%


David S. Miller153.42%15.88%


Daniel Borkmann40.91%15.88%


Hannes Frederic Sowa10.23%15.88%


Jorge Boncompte10.23%15.88%


Total438100.00%17100.00%




EXPORT_SYMBOL_GPL(__udp4_lib_lookup);




static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb,
						 __be16 sport, __be16 dport,
						 struct udp_table *udptable)
{
	const struct iphdr *iph = ip_hdr(skb);

	return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport,
				 iph->daddr, dport, inet_iif(skb),
				 udptable, skb);
}


Contributors
PersonTokensPropCommitsCommitProp
KOVACS Krisztian6494.12%133.33%


Craig Gallek22.94%133.33%


Eric Dumazet22.94%133.33%


Total68100.00%3100.00%






struct sock *udp4_lib_lookup_skb(struct sk_buff *skb,
				 __be16 sport, __be16 dport)
{
	return __udp4_lib_lookup_skb(skb, sport, dport, &udp_table);
}

Contributors
PersonTokensPropCommitsCommitProp
Tom Herbert2993.55%150.00%


Alexander Duyck26.45%150.00%


Total31100.00%2100.00%




EXPORT_SYMBOL_GPL(udp4_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_IPV4)



struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
			     __be32 daddr, __be16 dport, int dif)
{
	struct sock *sk;

	sk = __udp4_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
KOVACS Krisztian4358.11%125.00%


Eric Dumazet2939.19%250.00%


Craig Gallek22.70%125.00%


Total74100.00%4100.00%




EXPORT_SYMBOL_GPL(udp4_lib_lookup);
#endif




static inline bool __udp_is_mcast_sock(struct net *net, struct sock *sk,
				       __be16 loc_port, __be32 loc_addr,
				       __be16 rmt_port, __be32 rmt_addr,
				       int dif, unsigned short hnum)
{
	struct inet_sock *inet = inet_sk(sk);

	if (!net_eq(sock_net(sk), net) ||
	    udp_sk(sk)->udp_port_hash != hnum ||
	    (inet->inet_daddr && inet->inet_daddr != rmt_addr) ||
	    (inet->inet_dport != rmt_port && inet->inet_dport) ||
	    (inet->inet_rcv_saddr && inet->inet_rcv_saddr != loc_addr) ||
	    ipv6_only_sock(sk) ||
	    (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
		return false;
	if (!ip_mc_sf_allow(sk, loc_addr, rmt_addr, dif))
		return false;
	return true;
}


Contributors
PersonTokensPropCommitsCommitProp
David S. Miller9062.50%120.00%


Shawn Bohrer2920.14%120.00%


Eric Dumazet2517.36%360.00%


Total144100.00%5100.00%



/*
 * This routine is called by the ICMP module when it gets some
 * sort of error condition.  If err < 0 then the socket should
 * be closed and the error returned to the user.  If err > 0
 * it's just the icmp type << 8 | icmp code.
 * Header points to the ip header of the error packet. We move
 * on past this. Then (as it used to claim before adjustment)
 * header points to the first 8 bytes of the udp header.  We need
 * to find the appropriate port.
 */




void __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
{
	struct inet_sock *inet;
	const struct iphdr *iph = (const struct iphdr *)skb->data;
	struct udphdr *uh = (struct udphdr *)(skb->data+(iph->ihl<<2));
	const int type = icmp_hdr(skb)->type;
	const int code = icmp_hdr(skb)->code;
	struct sock *sk;
	int harderr;
	int err;
	struct net *net = dev_net(skb->dev);

	sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,
			iph->saddr, uh->source, skb->dev->ifindex, udptable,
			NULL);
	if (!sk) {
		__ICMP_INC_STATS(net, ICMP_MIB_INERRORS);
		return;	/* No socket for error */
	}

	err = 0;
	harderr = 0;
	inet = inet_sk(sk);

	switch (type) {
	default:
	case ICMP_TIME_EXCEEDED:
		err = EHOSTUNREACH;
		break;
	case ICMP_SOURCE_QUENCH:
		goto out;
	case ICMP_PARAMETERPROB:
		err = EPROTO;
		harderr = 1;
		break;
	case ICMP_DEST_UNREACH:
		if (code == ICMP_FRAG_NEEDED) {