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

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * 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!
 */
#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, struct sock *sk);
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 *off, int *err);
static inline struct sk_buff *skb_recv_udp(struct sock *sk, unsigned int flags,
					   int noblock, int *err)
{
	int off = 0;

	return __skb_recv_udp(sk, flags, noblock, &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)
{
	netdev_features_t features = NETIF_F_SG;
	struct sk_buff *segs;

	/* Avoid csum recalculation by skb_segment unless userspace explicitly
	 * asks for the final checksum values
	 */
	if (!inet_get_convert_csum(sk))
		features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;

	/* UDP segmentation expects packets of type CHECKSUM_PARTIAL or
	 * CHECKSUM_NONE in __udp_gso_segment. UDP GRO indeed builds partial
	 * packets in udp_gro_complete_segment. As does UDP GSO, verified by
	 * udp_send_skb. But when those packets are looped in dev_loopback_xmit
	 * their ip_summed is set to CHECKSUM_UNNECESSARY. Reset in this
	 * specific case, where PARTIAL is both correct and required.
	 */
	if (skb->pkt_type == PACKET_LOOPBACK)
		skb->ip_summed = CHECKSUM_PARTIAL;

	/* the GSO CB lays after the UDP one, no need to save and restore any
	 * CB fragment
	 */
	segs = __skb_gso_segment(skb, features, false);
	if (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;
}

#ifdef CONFIG_BPF_STREAM_PARSER
struct sk_psock;
struct proto *udp_bpf_get_proto(struct sock *sk, struct sk_psock *psock);
#endif /* BPF_STREAM_PARSER */

#endif	/* _UDP_H */
Commit	Line	Data
2874c5fd	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
1da177e4 LT	2	/*
	3	* INET An implementation of the TCP/IP protocol suite for the LINUX
	4	* operating system. INET is implemented using the BSD Socket
	5	* interface as the means of communication with the user level.
	6	*
	7	* Definitions for the UDP module.
	8	*
	9	* Version: @(#)udp.h 1.0.2 05/07/93
	10	*
02c30a84	11	* Authors: Ross Biro
1da177e4 LT	12	* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
	13	*
	14	* Fixes:
	15	* Alan Cox : Turned on udp checksums. I don't want to
	16	* chase 'memory corruption' bugs that aren't!
1da177e4 LT	17	*/
	18	#ifndef _UDP_H
	19	#define _UDP_H
	20
1da177e4	21	#include <linux/list.h>
187f1882	22	#include <linux/bug.h>
14c85021	23	#include <net/inet_sock.h>
1da177e4 LT	24	#include <net/sock.h>
1da177e4 LT	25	#include <net/snmp.h>
ba4e58ec GR	26	#include <net/ip.h>
ba4e58ec GR	27	#include <linux/ipv6.h>
1da177e4	28	#include <linux/seq_file.h>
bd01f843	29	#include <linux/poll.h>
1da177e4	30
ba4e58ec GR	31	/**
	32	* struct udp_skb_cb - UDP(-Lite) private variables
	33	*
	34	* @header: private variables used by IPv4/IPv6
	35	* @cscov: checksum coverage length (UDP-Lite only)
	36	* @partial_cov: if set indicates partial csum coverage
	37	*/
	38	struct udp_skb_cb {
	39	union {
	40	struct inet_skb_parm h4;
dfd56b8b	41	#if IS_ENABLED(CONFIG_IPV6)
ba4e58ec GR	42	struct inet6_skb_parm h6;
	43	#endif
	44	} header;
	45	__u16 cscov;
	46	__u8 partial_cov;
	47	};
	48	#define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb))
1da177e4	49
fdcc8aa9 ED	50	/**
	51	* struct udp_hslot - UDP hash slot
	52	*
	53	* @head: head of list of sockets
	54	* @count: number of sockets in 'head' list
	55	* @lock: spinlock protecting changes to head/count
	56	*/
645ca708	57	struct udp_hslot {
ca065d0c	58	struct hlist_head head;
fdcc8aa9	59	int count;
645ca708 ED	60	spinlock_t lock;
645ca708 ED	61	} __attribute__((aligned(2 * sizeof(long))));
f86dcc5a	62
512615b6 ED	63	/**
	64	* struct udp_table - UDP table
	65	*
	66	* @hash: hash table, sockets are hashed on (local port)
	67	* @hash2: hash table, sockets are hashed on (local port, local address)
	68	* @mask: number of slots in hash tables, minus 1
	69	* @log: log2(number of slots in hash table)
	70	*/
645ca708	71	struct udp_table {
f86dcc5a	72	struct udp_hslot *hash;
512615b6 ED	73	struct udp_hslot *hash2;
	74	unsigned int mask;
	75	unsigned int log;
645ca708 ED	76	};
645ca708 ED	77	extern struct udp_table udp_table;
1a50bd06	78	void udp_table_init(struct udp_table , const char );
f86dcc5a	79	static inline struct udp_hslot udp_hashslot(struct udp_table table,
95c96174	80	struct net *net, unsigned int num)
f86dcc5a ED	81	{
	82	return &table->hash[udp_hashfn(net, num, table->mask)];
	83	}
512615b6 ED	84	/*
	85	* For secondary hash, net_hash_mix() is performed before calling
	86	* udp_hashslot2(), this explains difference with udp_hashslot()
	87	*/
	88	static inline struct udp_hslot udp_hashslot2(struct udp_table table,
	89	unsigned int hash)
	90	{
	91	return &table->hash2[hash & table->mask];
	92	}
1da177e4	93
1da177e4 LT	94	extern struct proto udp_prot;
1da177e4 LT	95
8d987e5c	96	extern atomic_long_t udp_memory_allocated;
95766fff HA	97
95766fff HA	98	/* sysctl variables for udp */
8d987e5c	99	extern long sysctl_udp_mem[3];
95766fff HA	100	extern int sysctl_udp_rmem_min;
	101	extern int sysctl_udp_wmem_min;
	102
14c85021	103	struct sk_buff;
1da177e4	104
ba4e58ec GR	105	/*
	106	* Generic checksumming routines for UDP(-Lite) v4 and v6
	107	*/
b51655b9	108	static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
ba4e58ec	109	{
bbdff225 TH	110	return (UDP_SKB_CB(skb)->cscov == skb->len ?
	111	__skb_checksum_complete(skb) :
	112	__skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov));
ba4e58ec GR	113	}
ba4e58ec GR	114
8e5200f5	115	static inline int udp_lib_checksum_complete(struct sk_buff *skb)
ba4e58ec	116	{
60476372	117	return !skb_csum_unnecessary(skb) &&
ba4e58ec GR	118	__udp_lib_checksum_complete(skb);
	119	}
	120
	121	/**
	122	* udp_csum_outgoing - compute UDPv4/v6 checksum over fragments
	123	* @sk: socket we are writing to
	124	* @skb: sk_buff containing the filled-in UDP header
	125	* (checksum field must be zeroed out)
	126	*/
868c86bc	127	static inline __wsum udp_csum_outgoing(struct sock sk, struct sk_buff skb)
ba4e58ec	128	{
9c70220b ACM	129	__wsum csum = csum_partial(skb_transport_header(skb),
9c70220b ACM	130	sizeof(struct udphdr), 0);
ba4e58ec GR	131	skb_queue_walk(&sk->sk_write_queue, skb) {
	132	csum = csum_add(csum, skb->csum);
	133	}
	134	return csum;
	135	}
	136
f6b9664f HX	137	static inline __wsum udp_csum(struct sk_buff *skb)
	138	{
	139	__wsum csum = csum_partial(skb_transport_header(skb),
	140	sizeof(struct udphdr), skb->csum);
	141
	142	for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next) {
	143	csum = csum_add(csum, skb->csum);
	144	}
	145	return csum;
	146	}
	147
af5fcba7 TH	148	static inline __sum16 udp_v4_check(int len, __be32 saddr,
	149	__be32 daddr, __wsum base)
	150	{
	151	return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base);
	152	}
	153
	154	void udp_set_csum(bool nocheck, struct sk_buff *skb,
	155	__be32 saddr, __be32 daddr, int len);
	156
e6afc8ac	157	static inline void udp_csum_pull_header(struct sk_buff *skb)
e6afc8ac	158	{
595d0b29 ED	159	if (!skb->csum_valid && skb->ip_summed == CHECKSUM_NONE)
595d0b29 ED	160	skb->csum = csum_partial(skb->data, sizeof(struct udphdr),
e6afc8ac	161	skb->csum);
	162	skb_pull_rcsum(skb, sizeof(struct udphdr));
	163	UDP_SKB_CB(skb)->cscov -= sizeof(struct udphdr);
	164	}
	165
a6024562 TH	166	typedef struct sock (udp_lookup_t)(struct sk_buff *skb, __be16 sport,
	167	__be16 dport);
	168
d4546c25	169	struct sk_buff udp_gro_receive(struct list_head head, struct sk_buff *skb,
9fd1ff5d	170	struct udphdr uh, struct sock sk);
a6024562	171	int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
57c67ff4	172
ee80d1eb	173	struct sk_buff __udp_gso_segment(struct sk_buff gso_skb,
9a0d41b3	174	netdev_features_t features);
ee80d1eb	175
57c67ff4 TH	176	static inline struct udphdr udp_gro_udphdr(struct sk_buff skb)
	177	{
	178	struct udphdr *uh;
	179	unsigned int hlen, off;
	180
	181	off = skb_gro_offset(skb);
	182	hlen = off + sizeof(*uh);
	183	uh = skb_gro_header_fast(skb, off);
	184	if (skb_gro_header_hard(skb, hlen))
	185	uh = skb_gro_header_slow(skb, hlen, off);
	186
	187	return uh;
	188	}
	189
ba4e58ec	190	/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
086c653f	191	static inline int udp_lib_hash(struct sock *sk)
ba4e58ec GR	192	{
ba4e58ec GR	193	BUG();
086c653f	194	return 0;
ba4e58ec GR	195	}
ba4e58ec GR	196
1a50bd06 JP	197	void udp_lib_unhash(struct sock *sk);
1a50bd06 JP	198	void udp_lib_rehash(struct sock *sk, u16 new_hash);
ba4e58ec GR	199
	200	static inline void udp_lib_close(struct sock *sk, long timeout)
	201	{
	202	sk_common_release(sk);
	203	}
	204
1a50bd06	205	int udp_lib_get_port(struct sock *sk, unsigned short snum,
1a50bd06	206	unsigned int hash2_nulladdr);
ba4e58ec	207
723b8e46 TH	208	u32 udp_flow_hashrnd(void);
723b8e46 TH	209
b8f1a556 TH	210	static inline __be16 udp_flow_src_port(struct net net, struct sk_buff skb,
	211	int min, int max, bool use_eth)
	212	{
	213	u32 hash;
	214
	215	if (min >= max) {
	216	/* Use default range */
	217	inet_get_local_port_range(net, &min, &max);
	218	}
	219
	220	hash = skb_get_hash(skb);
723b8e46 TH	221	if (unlikely(!hash)) {
	222	if (use_eth) {
	223	/* Can't find a normal hash, caller has indicated an
	224	* Ethernet packet so use that to compute a hash.
	225	*/
	226	hash = jhash(skb->data, 2 * ETH_ALEN,
	227	(__force u32) skb->protocol);
	228	} else {
	229	/* Can't derive any sort of hash for the packet, set
	230	* to some consistent random value.
	231	*/
	232	hash = udp_flow_hashrnd();
	233	}
b8f1a556 TH	234	}
	235
	236	/* Since this is being sent on the wire obfuscate hash a bit
	237	* to minimize possbility that any useful information to an
	238	* attacker is leaked. Only upper 16 bits are relevant in the
	239	* computation for 16 bit port value.
	240	*/
	241	hash ^= hash << 16;
	242
	243	return htons((((u64) hash * (max - min)) >> 32) + min);
	244	}
	245
6c206b20 PA	246	static inline int udp_rqueue_get(struct sock *sk)
	247	{
	248	return sk_rmem_alloc_get(sk) - READ_ONCE(udp_sk(sk)->forward_deficit);
	249	}
	250
6da5b0f0 MM	251	static inline bool udp_sk_bound_dev_eq(struct net *net, int bound_dev_if,
	252	int dif, int sdif)
	253	{
	254	#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
	255	return inet_bound_dev_eq(!!net->ipv4.sysctl_udp_l3mdev_accept,
	256	bound_dev_if, dif, sdif);
	257	#else
	258	return inet_bound_dev_eq(true, bound_dev_if, dif, sdif);
	259	#endif
	260	}
	261
ba4e58ec	262	/* net/ipv4/udp.c */
c915fe13	263	void udp_destruct_sock(struct sock *sk);
f970bd9e PA	264	void skb_consume_udp(struct sock sk, struct sk_buff skb, int len);
f970bd9e PA	265	int __udp_enqueue_schedule_skb(struct sock sk, struct sk_buff skb);
7c13f97f	266	void udp_skb_destructor(struct sock sk, struct sk_buff skb);
2276f58a	267	struct sk_buff __skb_recv_udp(struct sock sk, unsigned int flags,
fd69c399	268	int noblock, int off, int err);
7c13f97f PA	269	static inline struct sk_buff skb_recv_udp(struct sock sk, unsigned int flags,
	270	int noblock, int *err)
	271	{
fd69c399	272	int off = 0;
7c13f97f	273
fd69c399	274	return __skb_recv_udp(sk, flags, noblock, &off, err);
7c13f97f	275	}
f970bd9e	276
7487449c	277	int udp_v4_early_demux(struct sk_buff *skb);
64f0f5d1	278	bool udp_sk_rx_dst_set(struct sock sk, struct dst_entry dst);
1a50bd06 JP	279	int udp_get_port(struct sock *sk, unsigned short snum,
	280	int (saddr_cmp)(const struct sock ,
	281	const struct sock *));
32bbd879	282	int udp_err(struct sk_buff *, u32);
5d77dca8	283	int udp_abort(struct sock *sk, int err);
1b784140	284	int udp_sendmsg(struct sock sk, struct msghdr msg, size_t len);
1a50bd06 JP	285	int udp_push_pending_frames(struct sock *sk);
1a50bd06 JP	286	void udp_flush_pending_frames(struct sock *sk);
2e8de857	287	int udp_cmsg_send(struct sock sk, struct msghdr msg, u16 *gso_size);
1a50bd06 JP	288	void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst);
	289	int udp_rcv(struct sk_buff *skb);
	290	int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
f970bd9e	291	int udp_init_sock(struct sock *sk);
d74bad4e	292	int udp_pre_connect(struct sock sk, struct sockaddr uaddr, int addr_len);
286c72de	293	int __udp_disconnect(struct sock *sk, int flags);
1a50bd06	294	int udp_disconnect(struct sock *sk, int flags);
a11e1d43	295	__poll_t udp_poll(struct file file, struct socket sock, poll_table *wait);
1a50bd06	296	struct sk_buff skb_udp_tunnel_segment(struct sk_buff skb,
8bce6d7d TH	297	netdev_features_t features,
8bce6d7d TH	298	bool is_ipv6);
1a50bd06 JP	299	int udp_lib_getsockopt(struct sock *sk, int level, int optname,
	300	char __user optval, int __user optlen);
	301	int udp_lib_setsockopt(struct sock *sk, int level, int optname,
	302	char __user *optval, unsigned int optlen,
	303	int (push_pending_frames)(struct sock ));
	304	struct sock udp4_lib_lookup(struct net net, __be32 saddr, __be16 sport,
	305	__be32 daddr, __be16 dport, int dif);
	306	struct sock __udp4_lib_lookup(struct net net, __be32 saddr, __be16 sport,
fb74c277	307	__be32 daddr, __be16 dport, int dif, int sdif,
538950a1	308	struct udp_table tbl, struct sk_buff skb);
63058308 TH	309	struct sock udp4_lib_lookup_skb(struct sk_buff skb,
63058308 TH	310	__be16 sport, __be16 dport);
1a50bd06 JP	311	struct sock udp6_lib_lookup(struct net net,
	312	const struct in6_addr *saddr, __be16 sport,
	313	const struct in6_addr *daddr, __be16 dport,
	314	int dif);
	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,
1801b570	318	int dif, int sdif, struct udp_table *tbl,
538950a1	319	struct sk_buff *skb);
63058308 TH	320	struct sock udp6_lib_lookup_skb(struct sk_buff skb,
63058308 TH	321	__be16 sport, __be16 dport);
bcd41303	322
b26bbdae PA	323	/* UDP uses skb->dev_scratch to cache as much information as possible and avoid
	324	* possibly multiple cache miss on dequeue()
	325	*/
b26bbdae	326	struct udp_dev_scratch {
dce4551c PA	327	/* skb->truesize and the stateless bit are embedded in a single field;
	328	* do not use a bitfield since the compiler emits better/smaller code
	329	* this way
	330	*/
	331	u32 _tsize_state;
	332
	333	#if BITS_PER_LONG == 64
	334	/* len and the bit needed to compute skb_csum_unnecessary
	335	* will be on cold cache lines at recvmsg time.
	336	* skb->len can be stored on 16 bits since the udp header has been
	337	* already validated and pulled.
	338	*/
b26bbdae PA	339	u16 len;
	340	bool is_linear;
	341	bool csum_unnecessary;
dce4551c	342	#endif
b26bbdae PA	343	};
b26bbdae PA	344
dce4551c PA	345	static inline struct udp_dev_scratch udp_skb_scratch(struct sk_buff skb)
	346	{
	347	return (struct udp_dev_scratch *)&skb->dev_scratch;
	348	}
	349
	350	#if BITS_PER_LONG == 64
b26bbdae PA	351	static inline unsigned int udp_skb_len(struct sk_buff *skb)
b26bbdae PA	352	{
dce4551c	353	return udp_skb_scratch(skb)->len;
b26bbdae PA	354	}
	355
	356	static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
	357	{
dce4551c	358	return udp_skb_scratch(skb)->csum_unnecessary;
b26bbdae PA	359	}
	360
	361	static inline bool udp_skb_is_linear(struct sk_buff *skb)
	362	{
dce4551c	363	return udp_skb_scratch(skb)->is_linear;
b26bbdae PA	364	}
	365
	366	#else
	367	static inline unsigned int udp_skb_len(struct sk_buff *skb)
	368	{
	369	return skb->len;
	370	}
	371
	372	static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
	373	{
	374	return skb_csum_unnecessary(skb);
	375	}
	376
	377	static inline bool udp_skb_is_linear(struct sk_buff *skb)
	378	{
	379	return !skb_is_nonlinear(skb);
	380	}
	381	#endif
	382
	383	static inline int copy_linear_skb(struct sk_buff *skb, int len, int off,
	384	struct iov_iter *to)
	385	{
42b73059	386	int n;
b26bbdae	387
42b73059 AV	388	n = copy_to_iter(skb->data + off, len, to);
42b73059 AV	389	if (n == len)
b26bbdae PA	390	return 0;
b26bbdae PA	391
42b73059	392	iov_iter_revert(to, n);
b26bbdae PA	393	return -EFAULT;
	394	}
	395
ba4e58ec GR	396	/*
	397	* SNMP statistics for UDP and UDP-Lite
	398	*/
6aef70a8 ED	399	#define UDP_INC_STATS(net, field, is_udplite) do { \
	400	if (is_udplite) SNMP_INC_STATS((net)->mib.udplite_statistics, field); \
	401	else SNMP_INC_STATS((net)->mib.udp_statistics, field); } while(0)
02c22347	402	#define __UDP_INC_STATS(net, field, is_udplite) do { \
13415e46 ED	403	if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_statistics, field); \
13415e46 ED	404	else __SNMP_INC_STATS((net)->mib.udp_statistics, field); } while(0)
1da177e4	405
02c22347	406	#define __UDP6_INC_STATS(net, field, is_udplite) do { \
13415e46 ED	407	if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);\
13415e46 ED	408	else __SNMP_INC_STATS((net)->mib.udp_stats_in6, field); \
0c7ed677	409	} while(0)
6aef70a8 ED	410	#define UDP6_INC_STATS(net, field, __lite) do { \
	411	if (__lite) SNMP_INC_STATS((net)->mib.udplite_stats_in6, field); \
	412	else SNMP_INC_STATS((net)->mib.udp_stats_in6, field); \
0c7ed677	413	} while(0)
1781f7f5	414
dfd56b8b	415	#if IS_ENABLED(CONFIG_IPV6)
cf329aa4 PA	416	#define __UDPX_MIB(sk, ipv4) \
	417	({ \
	418	ipv4 ? (IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_statistics : \
	419	sock_net(sk)->mib.udp_statistics) : \
	420	(IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_stats_in6 : \
	421	sock_net(sk)->mib.udp_stats_in6); \
	422	})
1781f7f5	423	#else
cf329aa4 PA	424	#define __UDPX_MIB(sk, ipv4) \
	425	({ \
	426	IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_statistics : \
	427	sock_net(sk)->mib.udp_statistics; \
	428	})
1781f7f5 HX	429	#endif
1781f7f5 HX	430
cf329aa4 PA	431	#define __UDPX_INC_STATS(sk, field) \
	432	__SNMP_INC_STATS(__UDPX_MIB(sk, (sk)->sk_family == AF_INET), field)
	433
a3d2599b	434	#ifdef CONFIG_PROC_FS
1da177e4	435	struct udp_seq_afinfo {
73cb88ec AV	436	sa_family_t family;
73cb88ec AV	437	struct udp_table *udp_table;
1da177e4 LT	438	};
	439
	440	struct udp_iter_state {
6f191efe	441	struct seq_net_private p;
1da177e4	442	int bucket;
1da177e4 LT	443	};
1da177e4 LT	444
a3d2599b CH	445	void udp_seq_start(struct seq_file seq, loff_t *pos);
	446	void udp_seq_next(struct seq_file seq, void v, loff_t pos);
	447	void udp_seq_stop(struct seq_file seq, void v);
	448
c3506372 CH	449	extern const struct seq_operations udp_seq_ops;
c3506372 CH	450	extern const struct seq_operations udp6_seq_ops;
20380731	451
1a50bd06 JP	452	int udp4_proc_init(void);
1a50bd06 JP	453	void udp4_proc_exit(void);
a3d2599b	454	#endif /* CONFIG_PROC_FS */
95766fff	455
1a50bd06	456	int udpv4_offload_init(void);
da5bab07	457
1a50bd06	458	void udp_init(void);
d7ca4cc0	459
f2e9de21	460	DECLARE_STATIC_KEY_FALSE(udp_encap_needed_key);
1a50bd06	461	void udp_encap_enable(void);
d7f3f621	462	#if IS_ENABLED(CONFIG_IPV6)
f2e9de21	463	DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
1a50bd06	464	void udpv6_encap_enable(void);
d7f3f621	465	#endif
dddb64bc	466
cf329aa4 PA	467	static inline struct sk_buff udp_rcv_segment(struct sock sk,
	468	struct sk_buff *skb, bool ipv4)
	469	{
f2696099	470	netdev_features_t features = NETIF_F_SG;
cf329aa4 PA	471	struct sk_buff *segs;
cf329aa4 PA	472
f2696099 ST	473	/* Avoid csum recalculation by skb_segment unless userspace explicitly
	474	* asks for the final checksum values
	475	*/
	476	if (!inet_get_convert_csum(sk))
	477	features \|= NETIF_F_IP_CSUM \| NETIF_F_IPV6_CSUM;
	478
d0208bf4 WB	479	/* UDP segmentation expects packets of type CHECKSUM_PARTIAL or
	480	* CHECKSUM_NONE in __udp_gso_segment. UDP GRO indeed builds partial
	481	* packets in udp_gro_complete_segment. As does UDP GSO, verified by
	482	* udp_send_skb. But when those packets are looped in dev_loopback_xmit
	483	* their ip_summed is set to CHECKSUM_UNNECESSARY. Reset in this
	484	* specific case, where PARTIAL is both correct and required.
	485	*/
6cd021a5 WB	486	if (skb->pkt_type == PACKET_LOOPBACK)
	487	skb->ip_summed = CHECKSUM_PARTIAL;
	488
cf329aa4 PA	489	/* the GSO CB lays after the UDP one, no need to save and restore any
	490	* CB fragment
	491	*/
f2696099	492	segs = __skb_gso_segment(skb, features, false);
974ceb21	493	if (IS_ERR_OR_NULL(segs)) {
cf329aa4 PA	494	int segs_nr = skb_shinfo(skb)->gso_segs;
	495
	496	atomic_add(segs_nr, &sk->sk_drops);
	497	SNMP_ADD_STATS(__UDPX_MIB(sk, ipv4), UDP_MIB_INERRORS, segs_nr);
	498	kfree_skb(skb);
	499	return NULL;
	500	}
	501
	502	consume_skb(skb);
	503	return segs;
	504	}
	505
edc6741c LB	506	#ifdef CONFIG_BPF_STREAM_PARSER
	507	struct sk_psock;
	508	struct proto udp_bpf_get_proto(struct sock sk, struct sk_psock *psock);
	509	#endif /* BPF_STREAM_PARSER */
	510
1da177e4	511	#endif /* _UDP_H */