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 protocol.
7 *
8 * Version:	@(#)udp.h	1.0.2	04/28/93
9 *
10 * Author:	Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 *
12 *		This program is free software; you can redistribute it and/or
13 *		modify it under the terms of the GNU General Public License
14 *		as published by the Free Software Foundation; either version
15 *		2 of the License, or (at your option) any later version.
16 */
17#ifndef _LINUX_UDP_H
18#define _LINUX_UDP_H
19
20#include <linux/types.h>
21
22struct udphdr {
23	__be16	source;
24	__be16	dest;
25	__be16	len;
26	__sum16	check;
27};
28
29#ifdef __KERNEL__
30#include <linux/skbuff.h>
31
32static inline struct udphdr *udp_hdr(const struct sk_buff *skb)
33{
34	return (struct udphdr *)skb_transport_header(skb);
35}
36#endif
37
38/* UDP socket options */
39#define UDP_CORK	1	/* Never send partially complete segments */
40#define UDP_ENCAP	100	/* Set the socket to accept encapsulated packets */
41
42/* UDP encapsulation types */
43#define UDP_ENCAP_ESPINUDP_NON_IKE	1 /* draft-ietf-ipsec-nat-t-ike-00/01 */
44#define UDP_ENCAP_ESPINUDP	2 /* draft-ietf-ipsec-udp-encaps-06 */
45
46#ifdef __KERNEL__
47#include <linux/types.h>
48
49#include <net/inet_sock.h>
50#define UDP_HTABLE_SIZE		128
51
52struct udp_sock {
53	/* inet_sock has to be the first member */
54	struct inet_sock inet;
55	int		 pending;	/* Any pending frames ? */
56	unsigned int	 corkflag;	/* Cork is required */
57  	__u16		 encap_type;	/* Is this an Encapsulation socket? */
58	/*
59	 * Following member retains the information to create a UDP header
60	 * when the socket is uncorked.
61	 */
62	__u16		 len;		/* total length of pending frames */
63	/*
64	 * Fields specific to UDP-Lite.
65	 */
66	__u16		 pcslen;
67	__u16		 pcrlen;
68/* indicator bits used by pcflag: */
69#define UDPLITE_BIT      0x1  		/* set by udplite proto init function */
70#define UDPLITE_SEND_CC  0x2  		/* set via udplite setsockopt         */
71#define UDPLITE_RECV_CC  0x4		/* set via udplite setsocktopt        */
72	__u8		 pcflag;        /* marks socket as UDP-Lite if > 0    */
73};
74
75static inline struct udp_sock *udp_sk(const struct sock *sk)
76{
77	return (struct udp_sock *)sk;
78}
79#define IS_UDPLITE(__sk) (udp_sk(__sk)->pcflag)
80
81#endif
82
83#endif	/* _LINUX_UDP_H */
84