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  *
10  * Authors:	Ross Biro, <bir7@leland.Stanford.Edu>
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 
25 #include <linux/udp.h>
26 #include <linux/poll.h>
27 #include <net/sock.h>
28 #include <net/snmp.h>
29 
30 #define UDP_HTABLE_SIZE		128
31 
32 /* udp.c: This needs to be shared by v4 and v6 because the lookup
33  *        and hashing code needs to work with different AF's yet
34  *        the port space is shared.
35  */
36 extern struct sock *udp_hash[UDP_HTABLE_SIZE];
37 extern rwlock_t udp_hash_lock;
38 
39 extern int udp_port_rover;
40 
udp_lport_inuse(u16 num)41 static inline int udp_lport_inuse(u16 num)
42 {
43 	struct sock *sk = udp_hash[num & (UDP_HTABLE_SIZE - 1)];
44 
45 	for(; sk != NULL; sk = sk->next) {
46 		if(sk->num == num)
47 			return 1;
48 	}
49 	return 0;
50 }
51 
52 /* Note: this must match 'valbool' in sock_setsockopt */
53 #define UDP_CSUM_NOXMIT		1
54 
55 /* Used by SunRPC/xprt layer. */
56 #define UDP_CSUM_NORCV		2
57 
58 /* Default, as per the RFC, is to always do csums. */
59 #define UDP_CSUM_DEFAULT	0
60 
61 extern struct proto udp_prot;
62 
63 
64 extern void	udp_err(struct sk_buff *, u32);
65 extern int	udp_connect(struct sock *sk,
66 			    struct sockaddr *usin, int addr_len);
67 
68 extern int	udp_sendmsg(struct sock *sk, struct msghdr *msg, int len);
69 
70 extern int	udp_rcv(struct sk_buff *skb);
71 extern int	udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
72 extern int	udp_disconnect(struct sock *sk, int flags);
73 extern unsigned int udp_poll(struct file *file, struct socket *sock,
74 			     poll_table *wait);
75 
76 extern struct udp_mib udp_statistics[NR_CPUS*2];
77 #define UDP_INC_STATS(field)		SNMP_INC_STATS(udp_statistics, field)
78 #define UDP_INC_STATS_BH(field)		SNMP_INC_STATS_BH(udp_statistics, field)
79 #define UDP_INC_STATS_USER(field) 	SNMP_INC_STATS_USER(udp_statistics, field)
80 
81 #endif	/* _UDP_H */
82