include/net/udp.h - kernel/skids - Git at Google

 /*
  * 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 <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 defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
 		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_nulls_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;
 extern void udp_table_init(struct udp_table *, const char *);
 static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
 					     struct net *net, unsigned 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];
 }

 /* Note: this must match 'valbool' in sock_setsockopt */
 #define UDP_CSUM_NOXMIT		1

 /* Used by SunRPC/xprt layer. */
 #define UDP_CSUM_NORCV		2

 /* Default, as per the RFC, is to always do csums. */
 #define UDP_CSUM_DEFAULT	0

 extern struct proto udp_prot;

 extern atomic_t udp_memory_allocated;

 /* sysctl variables for udp */
 extern int 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 __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;
 }

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

 extern void udp_lib_unhash(struct sock *sk);
 extern 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);
 }

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

 /* net/ipv4/udp.c */
 extern int	udp_get_port(struct sock *sk, unsigned short snum,
 			     int (*saddr_cmp)(const struct sock *, const struct sock *));
 extern void	udp_err(struct sk_buff *, u32);

 extern int	udp_sendmsg(struct kiocb *iocb, struct sock *sk,
 			    struct msghdr *msg, size_t len);
 extern void	udp_flush_pending_frames(struct sock *sk);

 extern int	udp_rcv(struct sk_buff *skb);
 extern int	udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
 extern int	udp_disconnect(struct sock *sk, int flags);
 extern unsigned int udp_poll(struct file *file, struct socket *sock,
 			     poll_table *wait);
 extern int 	udp_lib_getsockopt(struct sock *sk, int level, int optname,
 			           char __user *optval, int __user *optlen);
 extern int 	udp_lib_setsockopt(struct sock *sk, int level, int optname,
 				   char __user *optval, unsigned int optlen,
 				   int (*push_pending_frames)(struct sock *));

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

 /*
  * 	SNMP statistics for UDP and UDP-Lite
  */
 #define UDP_INC_STATS_USER(net, field, is_udplite)	      do { \
 	if (is_udplite) SNMP_INC_STATS_USER((net)->mib.udplite_statistics, field);       \
 	else		SNMP_INC_STATS_USER((net)->mib.udp_statistics, field);  }  while(0)
 #define UDP_INC_STATS_BH(net, field, is_udplite) 	      do { \
 	if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_statistics, field);         \
 	else		SNMP_INC_STATS_BH((net)->mib.udp_statistics, field);    }  while(0)

 #define UDP6_INC_STATS_BH(net, field, is_udplite) 	    do { \
 	if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_stats_in6, field);\
 	else		SNMP_INC_STATS_BH((net)->mib.udp_stats_in6, field);  \
 } while(0)
 #define UDP6_INC_STATS_USER(net, field, __lite)		    do { \
 	if (__lite) SNMP_INC_STATS_USER((net)->mib.udplite_stats_in6, field);  \
 	else	    SNMP_INC_STATS_USER((net)->mib.udp_stats_in6, field);      \
 } while(0)

 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 #define UDPX_INC_STATS_BH(sk, field) \
 	do { \
 		if ((sk)->sk_family == AF_INET) \
 			UDP_INC_STATS_BH(sock_net(sk), field, 0); \
 		else \
 			UDP6_INC_STATS_BH(sock_net(sk), field, 0); \
 	} while (0);
 #else
 #define UDPX_INC_STATS_BH(sk, field) UDP_INC_STATS_BH(sock_net(sk), field, 0)
 #endif

 /* /proc */
 struct udp_seq_afinfo {
 	char			*name;
 	sa_family_t		family;
 	struct udp_table	*udp_table;
 	struct file_operations	seq_fops;
 	struct seq_operations	seq_ops;
 };

 struct udp_iter_state {
 	struct seq_net_private  p;
 	sa_family_t		family;
 	int			bucket;
 	struct udp_table	*udp_table;
 };

 #ifdef CONFIG_PROC_FS
 extern int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo);
 extern void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo);

 extern int  udp4_proc_init(void);
 extern void udp4_proc_exit(void);
 #endif

 extern void udp_init(void);

 extern int udp4_ufo_send_check(struct sk_buff *skb);
 extern struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, int features);
 #endif	/* _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 <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 defined(CONFIG_IPV6) \|\| defined (CONFIG_IPV6_MODULE)
	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_nulls_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;
	extern void udp_table_init(struct udp_table , const char );
	static inline struct udp_hslot udp_hashslot(struct udp_table table,
	struct net *net, unsigned 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];
	}

	/* Note: this must match 'valbool' in sock_setsockopt */
	#define UDP_CSUM_NOXMIT 1

	/* Used by SunRPC/xprt layer. */
	#define UDP_CSUM_NORCV 2

	/* Default, as per the RFC, is to always do csums. */
	#define UDP_CSUM_DEFAULT 0

	extern struct proto udp_prot;

	extern atomic_t udp_memory_allocated;

	/* sysctl variables for udp */
	extern int 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 __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;
	}

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

	extern void udp_lib_unhash(struct sock *sk);
	extern 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);
	}

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

	/* net/ipv4/udp.c */
	extern int udp_get_port(struct sock *sk, unsigned short snum,
	int (saddr_cmp)(const struct sock , const struct sock *));
	extern void udp_err(struct sk_buff *, u32);

	extern int udp_sendmsg(struct kiocb iocb, struct sock sk,
	struct msghdr *msg, size_t len);
	extern void udp_flush_pending_frames(struct sock *sk);

	extern int udp_rcv(struct sk_buff *skb);
	extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
	extern int udp_disconnect(struct sock *sk, int flags);
	extern unsigned int udp_poll(struct file file, struct socket sock,
	poll_table *wait);
	extern int udp_lib_getsockopt(struct sock *sk, int level, int optname,
	char __user optval, int __user optlen);
	extern int udp_lib_setsockopt(struct sock *sk, int level, int optname,
	char __user *optval, unsigned int optlen,
	int (push_pending_frames)(struct sock ));

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

	/*
	* SNMP statistics for UDP and UDP-Lite
	*/
	#define UDP_INC_STATS_USER(net, field, is_udplite) do { \
	if (is_udplite) SNMP_INC_STATS_USER((net)->mib.udplite_statistics, field); \
	else SNMP_INC_STATS_USER((net)->mib.udp_statistics, field); } while(0)
	#define UDP_INC_STATS_BH(net, field, is_udplite) do { \
	if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_statistics, field); \
	else SNMP_INC_STATS_BH((net)->mib.udp_statistics, field); } while(0)

	#define UDP6_INC_STATS_BH(net, field, is_udplite) do { \
	if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_stats_in6, field);\
	else SNMP_INC_STATS_BH((net)->mib.udp_stats_in6, field); \
	} while(0)
	#define UDP6_INC_STATS_USER(net, field, __lite) do { \
	if (__lite) SNMP_INC_STATS_USER((net)->mib.udplite_stats_in6, field); \
	else SNMP_INC_STATS_USER((net)->mib.udp_stats_in6, field); \
	} while(0)

	#if defined(CONFIG_IPV6) \|\| defined(CONFIG_IPV6_MODULE)
	#define UDPX_INC_STATS_BH(sk, field) \
	do { \
	if ((sk)->sk_family == AF_INET) \
	UDP_INC_STATS_BH(sock_net(sk), field, 0); \
	else \
	UDP6_INC_STATS_BH(sock_net(sk), field, 0); \
	} while (0);
	#else
	#define UDPX_INC_STATS_BH(sk, field) UDP_INC_STATS_BH(sock_net(sk), field, 0)
	#endif

	/* /proc */
	struct udp_seq_afinfo {
	char *name;
	sa_family_t family;
	struct udp_table *udp_table;
	struct file_operations seq_fops;
	struct seq_operations seq_ops;
	};

	struct udp_iter_state {
	struct seq_net_private p;
	sa_family_t family;
	int bucket;
	struct udp_table *udp_table;
	};

	#ifdef CONFIG_PROC_FS
	extern int udp_proc_register(struct net net, struct udp_seq_afinfo afinfo);
	extern void udp_proc_unregister(struct net net, struct udp_seq_afinfo afinfo);

	extern int udp4_proc_init(void);
	extern void udp4_proc_exit(void);
	#endif

	extern void udp_init(void);

	extern int udp4_ufo_send_check(struct sk_buff *skb);
	extern struct sk_buff udp4_ufo_fragment(struct sk_buff skb, int features);
	#endif /* _UDP_H */