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 22 struct udphdr { 23 __be16 source; 24 __be16 dest; 25 __be16 len; 26 __sum16 check; 27 }; 28 29 /* UDP socket options */ 30 #define UDP_CORK 1 /* Never send partially complete segments */ 31 #define UDP_ENCAP 100 /* Set the socket to accept encapsulated packets */ 32 33 /* UDP encapsulation types */ 34 #define UDP_ENCAP_ESPINUDP_NON_IKE 1 /* draft-ietf-ipsec-nat-t-ike-00/01 */ 35 #define UDP_ENCAP_ESPINUDP 2 /* draft-ietf-ipsec-udp-encaps-06 */ 36 #define UDP_ENCAP_L2TPINUDP 3 /* rfc2661 */ 37 38 #ifdef __KERNEL__ 39 #include <net/inet_sock.h> 40 #include <linux/skbuff.h> 41 #include <net/netns/hash.h> 42 udp_hdr(const struct sk_buff * skb)43static inline struct udphdr *udp_hdr(const struct sk_buff *skb) 44 { 45 return (struct udphdr *)skb_transport_header(skb); 46 } 47 48 #define UDP_HTABLE_SIZE 128 49 udp_hashfn(struct net * net,const unsigned num)50static inline int udp_hashfn(struct net *net, const unsigned num) 51 { 52 return (num + net_hash_mix(net)) & (UDP_HTABLE_SIZE - 1); 53 } 54 55 struct udp_sock { 56 /* inet_sock has to be the first member */ 57 struct inet_sock inet; 58 int pending; /* Any pending frames ? */ 59 unsigned int corkflag; /* Cork is required */ 60 __u16 encap_type; /* Is this an Encapsulation socket? */ 61 /* 62 * Following member retains the information to create a UDP header 63 * when the socket is uncorked. 64 */ 65 __u16 len; /* total length of pending frames */ 66 /* 67 * Fields specific to UDP-Lite. 68 */ 69 __u16 pcslen; 70 __u16 pcrlen; 71 /* indicator bits used by pcflag: */ 72 #define UDPLITE_BIT 0x1 /* set by udplite proto init function */ 73 #define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */ 74 #define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */ 75 __u8 pcflag; /* marks socket as UDP-Lite if > 0 */ 76 __u8 unused[3]; 77 /* 78 * For encapsulation sockets. 79 */ 80 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); 81 }; 82 udp_sk(const struct sock * sk)83static inline struct udp_sock *udp_sk(const struct sock *sk) 84 { 85 return (struct udp_sock *)sk; 86 } 87 88 #define IS_UDPLITE(__sk) (udp_sk(__sk)->pcflag) 89 90 #endif 91 92 #endif /* _LINUX_UDP_H */ 93