[mirror_ubuntu-jammy-kernel.git] / include / net / udp.h

/*
 * 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.
 *
 *		Definitions for the UDP module.
 *
 * Version:	@(#)udp.h	1.0.2	05/07/93
 *
 * Authors:	Ross Biro
 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *
 * Fixes:
 *		Alan Cox	: Turned on udp checksums. I don't want to
 *				  chase 'memory corruption' bugs that aren't!
 *
 *		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.
 */
#ifndef _UDP_H
#define _UDP_H

#include <linux/list.h>
#include <linux/bug.h>
#include <net/inet_sock.h>
#include <net/sock.h>
#include <net/snmp.h>
#include <net/ip.h>
#include <linux/ipv6.h>
#include <linux/seq_file.h>
#include <linux/poll.h>

/**
 *	struct udp_skb_cb  -  UDP(-Lite) private variables
 *
 *	@header:      private variables used by IPv4/IPv6
 *	@cscov:       checksum coverage length (UDP-Lite only)
 *	@partial_cov: if set indicates partial csum coverage
 */
struct udp_skb_cb {
	union {
		struct inet_skb_parm	h4;
#if IS_ENABLED(CONFIG_IPV6)
		struct inet6_skb_parm	h6;
#endif
	} header;
	__u16		cscov;
	__u8		partial_cov;
};
#define UDP_SKB_CB(__skb)	((struct udp_skb_cb *)((__skb)->cb))

/**
 *	struct udp_hslot - UDP hash slot
 *
 *	@head:	head of list of sockets
 *	@count:	number of sockets in 'head' list
 *	@lock:	spinlock protecting changes to head/count
 */
struct udp_hslot {
	struct hlist_head	head;
	int			count;
	spinlock_t		lock;
} __attribute__((aligned(2 * sizeof(long))));

/**
 *	struct udp_table - UDP table
 *
 *	@hash:	hash table, sockets are hashed on (local port)
 *	@hash2:	hash table, sockets are hashed on (local port, local address)
 *	@mask:	number of slots in hash tables, minus 1
 *	@log:	log2(number of slots in hash table)
 */
struct udp_table {
	struct udp_hslot	*hash;
	struct udp_hslot	*hash2;
	unsigned int		mask;
	unsigned int		log;
};
extern struct udp_table udp_table;
void udp_table_init(struct udp_table *, const char *);
static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
					     struct net *net, unsigned int num)
{
	return &table->hash[udp_hashfn(net, num, table->mask)];
}
/*
 * For secondary hash, net_hash_mix() is performed before calling
 * udp_hashslot2(), this explains difference with udp_hashslot()
 */
static inline struct udp_hslot *udp_hashslot2(struct udp_table *table,
					      unsigned int hash)
{
	return &table->hash2[hash & table->mask];
}

extern struct proto udp_prot;

extern atomic_long_t udp_memory_allocated;

/* sysctl variables for udp */
extern long sysctl_udp_mem[3];
extern int sysctl_udp_rmem_min;
extern int sysctl_udp_wmem_min;

struct sk_buff;

/*
 *	Generic checksumming routines for UDP(-Lite) v4 and v6
 */
static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
{
	return (UDP_SKB_CB(skb)->cscov == skb->len ?
		__skb_checksum_complete(skb) :
		__skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov));
}

static inline int udp_lib_checksum_complete(struct sk_buff *skb)
{
	return !skb_csum_unnecessary(skb) &&
		__udp_lib_checksum_complete(skb);
}

/**
 * 	udp_csum_outgoing  -  compute UDPv4/v6 checksum over fragments
 * 	@sk: 	socket we are writing to
 * 	@skb: 	sk_buff containing the filled-in UDP header
 * 	        (checksum field must be zeroed out)
 */
static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
{
	__wsum csum = csum_partial(skb_transport_header(skb),
				   sizeof(struct udphdr), 0);
	skb_queue_walk(&sk->sk_write_queue, skb) {
		csum = csum_add(csum, skb->csum);
	}
	return csum;
}

static inline __wsum udp_csum(struct sk_buff *skb)
{
	__wsum csum = csum_partial(skb_transport_header(skb),
				   sizeof(struct udphdr), skb->csum);

	for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next) {
		csum = csum_add(csum, skb->csum);
	}
	return csum;
}

static inline __sum16 udp_v4_check(int len, __be32 saddr,
				   __be32 daddr, __wsum base)
{
	return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base);
}

void udp_set_csum(bool nocheck, struct sk_buff *skb,
		  __be32 saddr, __be32 daddr, int len);

static inline void udp_csum_pull_header(struct sk_buff *skb)
{
	if (!skb->csum_valid && skb->ip_summed == CHECKSUM_NONE)
		skb->csum = csum_partial(skb->data, sizeof(struct udphdr),
					 skb->csum);
	skb_pull_rcsum(skb, sizeof(struct udphdr));
	UDP_SKB_CB(skb)->cscov -= sizeof(struct udphdr);
}

typedef struct sock *(*udp_lookup_t)(struct sk_buff *skb, __be16 sport,
				     __be16 dport);

struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
				struct udphdr *uh, udp_lookup_t lookup);
int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);

struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
				  netdev_features_t features);

static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
{
	struct udphdr *uh;
	unsigned int hlen, off;

	off  = skb_gro_offset(skb);
	hlen = off + sizeof(*uh);
	uh   = skb_gro_header_fast(skb, off);
	if (skb_gro_header_hard(skb, hlen))
		uh = skb_gro_header_slow(skb, hlen, off);

	return uh;
}

/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
static inline int udp_lib_hash(struct sock *sk)
{
	BUG();
	return 0;
}

void udp_lib_unhash(struct sock *sk);
void udp_lib_rehash(struct sock *sk, u16 new_hash);

static inline void udp_lib_close(struct sock *sk, long timeout)
{
	sk_common_release(sk);
}

int udp_lib_get_port(struct sock *sk, unsigned short snum,
		     unsigned int hash2_nulladdr);

u32 udp_flow_hashrnd(void);

static inline __be16 udp_flow_src_port(struct net *net, struct sk_buff *skb,
				       int min, int max, bool use_eth)
{
	u32 hash;

	if (min >= max) {
		/* Use default range */
		inet_get_local_port_range(net, &min, &max);
	}

	hash = skb_get_hash(skb);
	if (unlikely(!hash)) {
		if (use_eth) {
			/* Can't find a normal hash, caller has indicated an
			 * Ethernet packet so use that to compute a hash.
			 */
			hash = jhash(skb->data, 2 * ETH_ALEN,
				     (__force u32) skb->protocol);
		} else {
			/* Can't derive any sort of hash for the packet, set
			 * to some consistent random value.
			 */
			hash = udp_flow_hashrnd();
		}
	}

	/* Since this is being sent on the wire obfuscate hash a bit
	 * to minimize possbility that any useful information to an
	 * attacker is leaked. Only upper 16 bits are relevant in the
	 * computation for 16 bit port value.
	 */
	hash ^= hash << 16;

	return htons((((u64) hash * (max - min)) >> 32) + min);
}

static inline int udp_rqueue_get(struct sock *sk)
{
	return sk_rmem_alloc_get(sk) - READ_ONCE(udp_sk(sk)->forward_deficit);
}

static inline bool udp_sk_bound_dev_eq(struct net *net, int bound_dev_if,
				       int dif, int sdif)
{
#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
	return inet_bound_dev_eq(!!net->ipv4.sysctl_udp_l3mdev_accept,
				 bound_dev_if, dif, sdif);
#else
	return inet_bound_dev_eq(true, bound_dev_if, dif, sdif);
#endif
}

/* net/ipv4/udp.c */
void udp_destruct_sock(struct sock *sk);
void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len);
int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb);
void udp_skb_destructor(struct sock *sk, struct sk_buff *skb);
struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
			       int noblock, int *peeked, int *off, int *err);
static inline struct sk_buff *skb_recv_udp(struct sock *sk, unsigned int flags,
					   int noblock, int *err)
{
	int peeked, off = 0;

	return __skb_recv_udp(sk, flags, noblock, &peeked, &off, err);
}

int udp_v4_early_demux(struct sk_buff *skb);
bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst);
int udp_get_port(struct sock *sk, unsigned short snum,
		 int (*saddr_cmp)(const struct sock *,
				  const struct sock *));
int udp_err(struct sk_buff *, u32);
int udp_abort(struct sock *sk, int err);
int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len);
int udp_push_pending_frames(struct sock *sk);
void udp_flush_pending_frames(struct sock *sk);
int udp_cmsg_send(struct sock *sk, struct msghdr *msg, u16 *gso_size);
void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst);
int udp_rcv(struct sk_buff *skb);
int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
int udp_init_sock(struct sock *sk);
int udp_pre_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
int __udp_disconnect(struct sock *sk, int flags);
int udp_disconnect(struct sock *sk, int flags);
__poll_t udp_poll(struct file *file, struct socket *sock, poll_table *wait);
struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb,
				       netdev_features_t features,
				       bool is_ipv6);
int udp_lib_getsockopt(struct sock *sk, int level, int optname,
		       char __user *optval, int __user *optlen);
int udp_lib_setsockopt(struct sock *sk, int level, int optname,
		       char __user *optval, unsigned int optlen,
		       int (*push_pending_frames)(struct sock *));
struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
			     __be32 daddr, __be16 dport, int dif);
struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
			       __be32 daddr, __be16 dport, int dif, int sdif,
			       struct udp_table *tbl, struct sk_buff *skb);
struct sock *udp4_lib_lookup_skb(struct sk_buff *skb,
				 __be16 sport, __be16 dport);
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 *__udp6_lib_lookup(struct net *net,
			       const struct in6_addr *saddr, __be16 sport,
			       const struct in6_addr *daddr, __be16 dport,
			       int dif, int sdif, struct udp_table *tbl,
			       struct sk_buff *skb);
struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
				 __be16 sport, __be16 dport);

/* UDP uses skb->dev_scratch to cache as much information as possible and avoid
 * possibly multiple cache miss on dequeue()
 */
struct udp_dev_scratch {
	/* skb->truesize and the stateless bit are embedded in a single field;
	 * do not use a bitfield since the compiler emits better/smaller code
	 * this way
	 */
	u32 _tsize_state;

#if BITS_PER_LONG == 64
	/* len and the bit needed to compute skb_csum_unnecessary
	 * will be on cold cache lines at recvmsg time.
	 * skb->len can be stored on 16 bits since the udp header has been
	 * already validated and pulled.
	 */
	u16 len;
	bool is_linear;
	bool csum_unnecessary;
#endif
};

static inline struct udp_dev_scratch *udp_skb_scratch(struct sk_buff *skb)
{
	return (struct udp_dev_scratch *)&skb->dev_scratch;
}

#if BITS_PER_LONG == 64
static inline unsigned int udp_skb_len(struct sk_buff *skb)
{
	return udp_skb_scratch(skb)->len;
}

static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
{
	return udp_skb_scratch(skb)->csum_unnecessary;
}

static inline bool udp_skb_is_linear(struct sk_buff *skb)
{
	return udp_skb_scratch(skb)->is_linear;
}

#else
static inline unsigned int udp_skb_len(struct sk_buff *skb)
{
	return skb->len;
}

static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
{
	return skb_csum_unnecessary(skb);
}

static inline bool udp_skb_is_linear(struct sk_buff *skb)
{
	return !skb_is_nonlinear(skb);
}
#endif

static inline int copy_linear_skb(struct sk_buff *skb, int len, int off,
				  struct iov_iter *to)
{
	int n;

	n = copy_to_iter(skb->data + off, len, to);
	if (n == len)
		return 0;

	iov_iter_revert(to, n);
	return -EFAULT;
}

/*
 * 	SNMP statistics for UDP and UDP-Lite
 */
#define UDP_INC_STATS(net, field, is_udplite)		      do { \
	if (is_udplite) SNMP_INC_STATS((net)->mib.udplite_statistics, field);       \
	else		SNMP_INC_STATS((net)->mib.udp_statistics, field);  }  while(0)
#define __UDP_INC_STATS(net, field, is_udplite) 	      do { \
	if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_statistics, field);         \
	else		__SNMP_INC_STATS((net)->mib.udp_statistics, field);    }  while(0)

#define __UDP6_INC_STATS(net, field, is_udplite)	    do { \
	if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);\
	else		__SNMP_INC_STATS((net)->mib.udp_stats_in6, field);  \
} while(0)
#define UDP6_INC_STATS(net, field, __lite)		    do { \
	if (__lite) SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);  \
	else	    SNMP_INC_STATS((net)->mib.udp_stats_in6, field);      \
} while(0)

#if IS_ENABLED(CONFIG_IPV6)
#define __UDPX_MIB(sk, ipv4)						\
({									\
	ipv4 ? (IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_statistics :	\
				 sock_net(sk)->mib.udp_statistics) :	\
		(IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_stats_in6 :	\
				 sock_net(sk)->mib.udp_stats_in6);	\
})
#else
#define __UDPX_MIB(sk, ipv4)						\
({									\
	IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_statistics :		\
			 sock_net(sk)->mib.udp_statistics;		\
})
#endif

#define __UDPX_INC_STATS(sk, field) \
	__SNMP_INC_STATS(__UDPX_MIB(sk, (sk)->sk_family == AF_INET), field)

#ifdef CONFIG_PROC_FS
struct udp_seq_afinfo {
	sa_family_t			family;
	struct udp_table		*udp_table;
};

struct udp_iter_state {
	struct seq_net_private  p;
	int			bucket;
};

void *udp_seq_start(struct seq_file *seq, loff_t *pos);
void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos);
void udp_seq_stop(struct seq_file *seq, void *v);

extern const struct seq_operations udp_seq_ops;
extern const struct seq_operations udp6_seq_ops;

int udp4_proc_init(void);
void udp4_proc_exit(void);
#endif /* CONFIG_PROC_FS */

int udpv4_offload_init(void);

void udp_init(void);

DECLARE_STATIC_KEY_FALSE(udp_encap_needed_key);
void udp_encap_enable(void);
#if IS_ENABLED(CONFIG_IPV6)
DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
void udpv6_encap_enable(void);
#endif

static inline struct sk_buff *udp_rcv_segment(struct sock *sk,
					      struct sk_buff *skb, bool ipv4)
{
	struct sk_buff *segs;

	/* the GSO CB lays after the UDP one, no need to save and restore any
	 * CB fragment
	 */
	segs = __skb_gso_segment(skb, NETIF_F_SG, false);
	if (unlikely(IS_ERR_OR_NULL(segs))) {
		int segs_nr = skb_shinfo(skb)->gso_segs;

		atomic_add(segs_nr, &sk->sk_drops);
		SNMP_ADD_STATS(__UDPX_MIB(sk, ipv4), UDP_MIB_INERRORS, segs_nr);
		kfree_skb(skb);
		return NULL;
	}

	consume_skb(skb);
	return segs;
}

#endif	/* _UDP_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* INET An implementation of the TCP/IP protocol suite for the LINUX
	3	* operating system. INET is implemented using the BSD Socket
	4	* interface as the means of communication with the user level.
	5	*
	6	* Definitions for the UDP module.
	7	*
	8	* Version: @(#)udp.h 1.0.2 05/07/93
	9	*
02c30a84	10	* Authors: Ross Biro
1da177e4 LT	11	* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
	12	*
	13	* Fixes:
	14	* Alan Cox : Turned on udp checksums. I don't want to
	15	* chase 'memory corruption' bugs that aren't!
	16	*
	17	* This program is free software; you can redistribute it and/or
	18	* modify it under the terms of the GNU General Public License
	19	* as published by the Free Software Foundation; either version
	20	* 2 of the License, or (at your option) any later version.
	21	*/
	22	#ifndef _UDP_H
	23	#define _UDP_H
	24
1da177e4	25	#include <linux/list.h>
187f1882	26	#include <linux/bug.h>
14c85021	27	#include <net/inet_sock.h>
1da177e4 LT	28	#include <net/sock.h>
1da177e4 LT	29	#include <net/snmp.h>
ba4e58ec GR	30	#include <net/ip.h>
ba4e58ec GR	31	#include <linux/ipv6.h>
1da177e4	32	#include <linux/seq_file.h>
bd01f843	33	#include <linux/poll.h>
1da177e4	34
ba4e58ec GR	35	/**
	36	* struct udp_skb_cb - UDP(-Lite) private variables
	37	*
	38	* @header: private variables used by IPv4/IPv6
	39	* @cscov: checksum coverage length (UDP-Lite only)
	40	* @partial_cov: if set indicates partial csum coverage
	41	*/
	42	struct udp_skb_cb {
	43	union {
	44	struct inet_skb_parm h4;
dfd56b8b	45	#if IS_ENABLED(CONFIG_IPV6)
ba4e58ec GR	46	struct inet6_skb_parm h6;
	47	#endif
	48	} header;
	49	__u16 cscov;
	50	__u8 partial_cov;
	51	};
	52	#define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb))
1da177e4	53
fdcc8aa9 ED	54	/**
	55	* struct udp_hslot - UDP hash slot
	56	*
	57	* @head: head of list of sockets
	58	* @count: number of sockets in 'head' list
	59	* @lock: spinlock protecting changes to head/count
	60	*/
645ca708	61	struct udp_hslot {
ca065d0c	62	struct hlist_head head;
fdcc8aa9	63	int count;
645ca708 ED	64	spinlock_t lock;
645ca708 ED	65	} __attribute__((aligned(2 * sizeof(long))));
f86dcc5a	66
512615b6 ED	67	/**
	68	* struct udp_table - UDP table
	69	*
	70	* @hash: hash table, sockets are hashed on (local port)
	71	* @hash2: hash table, sockets are hashed on (local port, local address)
	72	* @mask: number of slots in hash tables, minus 1
	73	* @log: log2(number of slots in hash table)
	74	*/
645ca708	75	struct udp_table {
f86dcc5a	76	struct udp_hslot *hash;
512615b6 ED	77	struct udp_hslot *hash2;
	78	unsigned int mask;
	79	unsigned int log;
645ca708 ED	80	};
645ca708 ED	81	extern struct udp_table udp_table;
1a50bd06	82	void udp_table_init(struct udp_table , const char );
f86dcc5a	83	static inline struct udp_hslot udp_hashslot(struct udp_table table,
95c96174	84	struct net *net, unsigned int num)
f86dcc5a ED	85	{
	86	return &table->hash[udp_hashfn(net, num, table->mask)];
	87	}
512615b6 ED	88	/*
	89	* For secondary hash, net_hash_mix() is performed before calling
	90	* udp_hashslot2(), this explains difference with udp_hashslot()
	91	*/
	92	static inline struct udp_hslot udp_hashslot2(struct udp_table table,
	93	unsigned int hash)
	94	{
	95	return &table->hash2[hash & table->mask];
	96	}
1da177e4	97
1da177e4 LT	98	extern struct proto udp_prot;
1da177e4 LT	99
8d987e5c	100	extern atomic_long_t udp_memory_allocated;
95766fff HA	101
95766fff HA	102	/* sysctl variables for udp */
8d987e5c	103	extern long sysctl_udp_mem[3];
95766fff HA	104	extern int sysctl_udp_rmem_min;
	105	extern int sysctl_udp_wmem_min;
	106
14c85021	107	struct sk_buff;
1da177e4	108
ba4e58ec GR	109	/*
	110	* Generic checksumming routines for UDP(-Lite) v4 and v6
	111	*/
b51655b9	112	static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
ba4e58ec	113	{
bbdff225 TH	114	return (UDP_SKB_CB(skb)->cscov == skb->len ?
	115	__skb_checksum_complete(skb) :
	116	__skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov));
ba4e58ec GR	117	}
ba4e58ec GR	118
8e5200f5	119	static inline int udp_lib_checksum_complete(struct sk_buff *skb)
ba4e58ec	120	{
60476372	121	return !skb_csum_unnecessary(skb) &&
ba4e58ec GR	122	__udp_lib_checksum_complete(skb);
	123	}
	124
	125	/**
	126	* udp_csum_outgoing - compute UDPv4/v6 checksum over fragments
	127	* @sk: socket we are writing to
	128	* @skb: sk_buff containing the filled-in UDP header
	129	* (checksum field must be zeroed out)
	130	*/
868c86bc	131	static inline __wsum udp_csum_outgoing(struct sock sk, struct sk_buff skb)
ba4e58ec	132	{
9c70220b ACM	133	__wsum csum = csum_partial(skb_transport_header(skb),
9c70220b ACM	134	sizeof(struct udphdr), 0);
ba4e58ec GR	135	skb_queue_walk(&sk->sk_write_queue, skb) {
	136	csum = csum_add(csum, skb->csum);
	137	}
	138	return csum;
	139	}
	140
f6b9664f HX	141	static inline __wsum udp_csum(struct sk_buff *skb)
	142	{
	143	__wsum csum = csum_partial(skb_transport_header(skb),
	144	sizeof(struct udphdr), skb->csum);
	145
	146	for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next) {
	147	csum = csum_add(csum, skb->csum);
	148	}
	149	return csum;
	150	}
	151
af5fcba7 TH	152	static inline __sum16 udp_v4_check(int len, __be32 saddr,
	153	__be32 daddr, __wsum base)
	154	{
	155	return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base);
	156	}
	157
	158	void udp_set_csum(bool nocheck, struct sk_buff *skb,
	159	__be32 saddr, __be32 daddr, int len);
	160
e6afc8ac	161	static inline void udp_csum_pull_header(struct sk_buff *skb)
e6afc8ac	162	{
595d0b29 ED	163	if (!skb->csum_valid && skb->ip_summed == CHECKSUM_NONE)
595d0b29 ED	164	skb->csum = csum_partial(skb->data, sizeof(struct udphdr),
e6afc8ac	165	skb->csum);
	166	skb_pull_rcsum(skb, sizeof(struct udphdr));
	167	UDP_SKB_CB(skb)->cscov -= sizeof(struct udphdr);
	168	}
	169
a6024562 TH	170	typedef struct sock (udp_lookup_t)(struct sk_buff *skb, __be16 sport,
	171	__be16 dport);
	172
d4546c25 DM	173	struct sk_buff udp_gro_receive(struct list_head head, struct sk_buff *skb,
d4546c25 DM	174	struct udphdr *uh, udp_lookup_t lookup);
a6024562	175	int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
57c67ff4	176
ee80d1eb	177	struct sk_buff __udp_gso_segment(struct sk_buff gso_skb,
9a0d41b3	178	netdev_features_t features);
ee80d1eb	179
57c67ff4 TH	180	static inline struct udphdr udp_gro_udphdr(struct sk_buff skb)
	181	{
	182	struct udphdr *uh;
	183	unsigned int hlen, off;
	184
	185	off = skb_gro_offset(skb);
	186	hlen = off + sizeof(*uh);
	187	uh = skb_gro_header_fast(skb, off);
	188	if (skb_gro_header_hard(skb, hlen))
	189	uh = skb_gro_header_slow(skb, hlen, off);
	190
	191	return uh;
	192	}
	193
ba4e58ec	194	/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
086c653f	195	static inline int udp_lib_hash(struct sock *sk)
ba4e58ec GR	196	{
ba4e58ec GR	197	BUG();
086c653f	198	return 0;
ba4e58ec GR	199	}
ba4e58ec GR	200
1a50bd06 JP	201	void udp_lib_unhash(struct sock *sk);
1a50bd06 JP	202	void udp_lib_rehash(struct sock *sk, u16 new_hash);
ba4e58ec GR	203
	204	static inline void udp_lib_close(struct sock *sk, long timeout)
	205	{
	206	sk_common_release(sk);
	207	}
	208
1a50bd06	209	int udp_lib_get_port(struct sock *sk, unsigned short snum,
1a50bd06	210	unsigned int hash2_nulladdr);
ba4e58ec	211
723b8e46 TH	212	u32 udp_flow_hashrnd(void);
723b8e46 TH	213
b8f1a556 TH	214	static inline __be16 udp_flow_src_port(struct net net, struct sk_buff skb,
	215	int min, int max, bool use_eth)
	216	{
	217	u32 hash;
	218
	219	if (min >= max) {
	220	/* Use default range */
	221	inet_get_local_port_range(net, &min, &max);
	222	}
	223
	224	hash = skb_get_hash(skb);
723b8e46 TH	225	if (unlikely(!hash)) {
	226	if (use_eth) {
	227	/* Can't find a normal hash, caller has indicated an
	228	* Ethernet packet so use that to compute a hash.
	229	*/
	230	hash = jhash(skb->data, 2 * ETH_ALEN,
	231	(__force u32) skb->protocol);
	232	} else {
	233	/* Can't derive any sort of hash for the packet, set
	234	* to some consistent random value.
	235	*/
	236	hash = udp_flow_hashrnd();
	237	}
b8f1a556 TH	238	}
	239
	240	/* Since this is being sent on the wire obfuscate hash a bit
	241	* to minimize possbility that any useful information to an
	242	* attacker is leaked. Only upper 16 bits are relevant in the
	243	* computation for 16 bit port value.
	244	*/
	245	hash ^= hash << 16;
	246
	247	return htons((((u64) hash * (max - min)) >> 32) + min);
	248	}
	249
6c206b20 PA	250	static inline int udp_rqueue_get(struct sock *sk)
	251	{
	252	return sk_rmem_alloc_get(sk) - READ_ONCE(udp_sk(sk)->forward_deficit);
	253	}
	254
6da5b0f0 MM	255	static inline bool udp_sk_bound_dev_eq(struct net *net, int bound_dev_if,
	256	int dif, int sdif)
	257	{
	258	#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
	259	return inet_bound_dev_eq(!!net->ipv4.sysctl_udp_l3mdev_accept,
	260	bound_dev_if, dif, sdif);
	261	#else
	262	return inet_bound_dev_eq(true, bound_dev_if, dif, sdif);
	263	#endif
	264	}
	265
ba4e58ec	266	/* net/ipv4/udp.c */
c915fe13	267	void udp_destruct_sock(struct sock *sk);
f970bd9e PA	268	void skb_consume_udp(struct sock sk, struct sk_buff skb, int len);
f970bd9e PA	269	int __udp_enqueue_schedule_skb(struct sock sk, struct sk_buff skb);
7c13f97f	270	void udp_skb_destructor(struct sock sk, struct sk_buff skb);
2276f58a PA	271	struct sk_buff __skb_recv_udp(struct sock sk, unsigned int flags,
2276f58a PA	272	int noblock, int peeked, int off, int *err);
7c13f97f PA	273	static inline struct sk_buff skb_recv_udp(struct sock sk, unsigned int flags,
	274	int noblock, int *err)
	275	{
	276	int peeked, off = 0;
	277
	278	return __skb_recv_udp(sk, flags, noblock, &peeked, &off, err);
	279	}
f970bd9e	280
7487449c	281	int udp_v4_early_demux(struct sk_buff *skb);
64f0f5d1	282	bool udp_sk_rx_dst_set(struct sock sk, struct dst_entry dst);
1a50bd06 JP	283	int udp_get_port(struct sock *sk, unsigned short snum,
	284	int (saddr_cmp)(const struct sock ,
	285	const struct sock *));
32bbd879	286	int udp_err(struct sk_buff *, u32);
5d77dca8	287	int udp_abort(struct sock *sk, int err);
1b784140	288	int udp_sendmsg(struct sock sk, struct msghdr msg, size_t len);
1a50bd06 JP	289	int udp_push_pending_frames(struct sock *sk);
1a50bd06 JP	290	void udp_flush_pending_frames(struct sock *sk);
2e8de857	291	int udp_cmsg_send(struct sock sk, struct msghdr msg, u16 *gso_size);
1a50bd06 JP	292	void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst);
	293	int udp_rcv(struct sk_buff *skb);
	294	int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
f970bd9e	295	int udp_init_sock(struct sock *sk);
d74bad4e	296	int udp_pre_connect(struct sock sk, struct sockaddr uaddr, int addr_len);
286c72de	297	int __udp_disconnect(struct sock *sk, int flags);
1a50bd06	298	int udp_disconnect(struct sock *sk, int flags);
a11e1d43	299	__poll_t udp_poll(struct file file, struct socket sock, poll_table *wait);
1a50bd06	300	struct sk_buff skb_udp_tunnel_segment(struct sk_buff skb,
8bce6d7d TH	301	netdev_features_t features,
8bce6d7d TH	302	bool is_ipv6);
1a50bd06 JP	303	int udp_lib_getsockopt(struct sock *sk, int level, int optname,
	304	char __user optval, int __user optlen);
	305	int udp_lib_setsockopt(struct sock *sk, int level, int optname,
	306	char __user *optval, unsigned int optlen,
	307	int (push_pending_frames)(struct sock ));
	308	struct sock udp4_lib_lookup(struct net net, __be32 saddr, __be16 sport,
	309	__be32 daddr, __be16 dport, int dif);
	310	struct sock __udp4_lib_lookup(struct net net, __be32 saddr, __be16 sport,
fb74c277	311	__be32 daddr, __be16 dport, int dif, int sdif,
538950a1	312	struct udp_table tbl, struct sk_buff skb);
63058308 TH	313	struct sock udp4_lib_lookup_skb(struct sk_buff skb,
63058308 TH	314	__be16 sport, __be16 dport);
1a50bd06 JP	315	struct sock udp6_lib_lookup(struct net net,
	316	const struct in6_addr *saddr, __be16 sport,
	317	const struct in6_addr *daddr, __be16 dport,
	318	int dif);
	319	struct sock __udp6_lib_lookup(struct net net,
	320	const struct in6_addr *saddr, __be16 sport,
	321	const struct in6_addr *daddr, __be16 dport,
1801b570	322	int dif, int sdif, struct udp_table *tbl,
538950a1	323	struct sk_buff *skb);
63058308 TH	324	struct sock udp6_lib_lookup_skb(struct sk_buff skb,
63058308 TH	325	__be16 sport, __be16 dport);
bcd41303	326
b26bbdae PA	327	/* UDP uses skb->dev_scratch to cache as much information as possible and avoid
	328	* possibly multiple cache miss on dequeue()
	329	*/
b26bbdae	330	struct udp_dev_scratch {
dce4551c PA	331	/* skb->truesize and the stateless bit are embedded in a single field;
	332	* do not use a bitfield since the compiler emits better/smaller code
	333	* this way
	334	*/
	335	u32 _tsize_state;
	336
	337	#if BITS_PER_LONG == 64
	338	/* len and the bit needed to compute skb_csum_unnecessary
	339	* will be on cold cache lines at recvmsg time.
	340	* skb->len can be stored on 16 bits since the udp header has been
	341	* already validated and pulled.
	342	*/
b26bbdae PA	343	u16 len;
	344	bool is_linear;
	345	bool csum_unnecessary;
dce4551c	346	#endif
b26bbdae PA	347	};
b26bbdae PA	348
dce4551c PA	349	static inline struct udp_dev_scratch udp_skb_scratch(struct sk_buff skb)
	350	{
	351	return (struct udp_dev_scratch *)&skb->dev_scratch;
	352	}
	353
	354	#if BITS_PER_LONG == 64
b26bbdae PA	355	static inline unsigned int udp_skb_len(struct sk_buff *skb)
b26bbdae PA	356	{
dce4551c	357	return udp_skb_scratch(skb)->len;
b26bbdae PA	358	}
	359
	360	static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
	361	{
dce4551c	362	return udp_skb_scratch(skb)->csum_unnecessary;
b26bbdae PA	363	}
	364
	365	static inline bool udp_skb_is_linear(struct sk_buff *skb)
	366	{
dce4551c	367	return udp_skb_scratch(skb)->is_linear;
b26bbdae PA	368	}
	369
	370	#else
	371	static inline unsigned int udp_skb_len(struct sk_buff *skb)
	372	{
	373	return skb->len;
	374	}
	375
	376	static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
	377	{
	378	return skb_csum_unnecessary(skb);
	379	}
	380
	381	static inline bool udp_skb_is_linear(struct sk_buff *skb)
	382	{
	383	return !skb_is_nonlinear(skb);
	384	}
	385	#endif
	386
	387	static inline int copy_linear_skb(struct sk_buff *skb, int len, int off,
	388	struct iov_iter *to)
	389	{
42b73059	390	int n;
b26bbdae	391
42b73059 AV	392	n = copy_to_iter(skb->data + off, len, to);
42b73059 AV	393	if (n == len)
b26bbdae PA	394	return 0;
b26bbdae PA	395
42b73059	396	iov_iter_revert(to, n);
b26bbdae PA	397	return -EFAULT;
	398	}
	399
ba4e58ec GR	400	/*
	401	* SNMP statistics for UDP and UDP-Lite
	402	*/
6aef70a8 ED	403	#define UDP_INC_STATS(net, field, is_udplite) do { \
	404	if (is_udplite) SNMP_INC_STATS((net)->mib.udplite_statistics, field); \
	405	else SNMP_INC_STATS((net)->mib.udp_statistics, field); } while(0)
02c22347	406	#define __UDP_INC_STATS(net, field, is_udplite) do { \
13415e46 ED	407	if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_statistics, field); \
13415e46 ED	408	else __SNMP_INC_STATS((net)->mib.udp_statistics, field); } while(0)
1da177e4	409
02c22347	410	#define __UDP6_INC_STATS(net, field, is_udplite) do { \
13415e46 ED	411	if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);\
13415e46 ED	412	else __SNMP_INC_STATS((net)->mib.udp_stats_in6, field); \
0c7ed677	413	} while(0)
6aef70a8 ED	414	#define UDP6_INC_STATS(net, field, __lite) do { \
	415	if (__lite) SNMP_INC_STATS((net)->mib.udplite_stats_in6, field); \
	416	else SNMP_INC_STATS((net)->mib.udp_stats_in6, field); \
0c7ed677	417	} while(0)
1781f7f5	418
dfd56b8b	419	#if IS_ENABLED(CONFIG_IPV6)
cf329aa4 PA	420	#define __UDPX_MIB(sk, ipv4) \
	421	({ \
	422	ipv4 ? (IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_statistics : \
	423	sock_net(sk)->mib.udp_statistics) : \
	424	(IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_stats_in6 : \
	425	sock_net(sk)->mib.udp_stats_in6); \
	426	})
1781f7f5	427	#else
cf329aa4 PA	428	#define __UDPX_MIB(sk, ipv4) \
	429	({ \
	430	IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_statistics : \
	431	sock_net(sk)->mib.udp_statistics; \
	432	})
1781f7f5 HX	433	#endif
1781f7f5 HX	434
cf329aa4 PA	435	#define __UDPX_INC_STATS(sk, field) \
	436	__SNMP_INC_STATS(__UDPX_MIB(sk, (sk)->sk_family == AF_INET), field)
	437
a3d2599b	438	#ifdef CONFIG_PROC_FS
1da177e4	439	struct udp_seq_afinfo {
73cb88ec AV	440	sa_family_t family;
73cb88ec AV	441	struct udp_table *udp_table;
1da177e4 LT	442	};
	443
	444	struct udp_iter_state {
6f191efe	445	struct seq_net_private p;
1da177e4	446	int bucket;
1da177e4 LT	447	};
1da177e4 LT	448
a3d2599b CH	449	void udp_seq_start(struct seq_file seq, loff_t *pos);
	450	void udp_seq_next(struct seq_file seq, void v, loff_t pos);
	451	void udp_seq_stop(struct seq_file seq, void v);
	452
c3506372 CH	453	extern const struct seq_operations udp_seq_ops;
c3506372 CH	454	extern const struct seq_operations udp6_seq_ops;
20380731	455
1a50bd06 JP	456	int udp4_proc_init(void);
1a50bd06 JP	457	void udp4_proc_exit(void);
a3d2599b	458	#endif /* CONFIG_PROC_FS */
95766fff	459
1a50bd06	460	int udpv4_offload_init(void);
da5bab07	461
1a50bd06	462	void udp_init(void);
d7ca4cc0	463
f2e9de21	464	DECLARE_STATIC_KEY_FALSE(udp_encap_needed_key);
1a50bd06	465	void udp_encap_enable(void);
d7f3f621	466	#if IS_ENABLED(CONFIG_IPV6)
f2e9de21	467	DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
1a50bd06	468	void udpv6_encap_enable(void);
d7f3f621	469	#endif
dddb64bc	470
cf329aa4 PA	471	static inline struct sk_buff udp_rcv_segment(struct sock sk,
	472	struct sk_buff *skb, bool ipv4)
	473	{
	474	struct sk_buff *segs;
	475
	476	/* the GSO CB lays after the UDP one, no need to save and restore any
	477	* CB fragment
	478	*/
	479	segs = __skb_gso_segment(skb, NETIF_F_SG, false);
	480	if (unlikely(IS_ERR_OR_NULL(segs))) {
	481	int segs_nr = skb_shinfo(skb)->gso_segs;
	482
	483	atomic_add(segs_nr, &sk->sk_drops);
	484	SNMP_ADD_STATS(__UDPX_MIB(sk, ipv4), UDP_MIB_INERRORS, segs_nr);
	485	kfree_skb(skb);
	486	return NULL;
	487	}
	488
	489	consume_skb(skb);
	490	return segs;
	491	}
	492
1da177e4	493	#endif /* _UDP_H */