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)43 static 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_MIN (CONFIG_BASE_SMALL ? 128 : 256)
49
udp_hashfn(struct net * net,unsigned num,unsigned mask)50 static inline int udp_hashfn(struct net *net, unsigned num, unsigned mask)
51 {
52 return (num + net_hash_mix(net)) & mask;
53 }
54
55 struct udp_sock {
56 /* inet_sock has to be the first member */
57 struct inet_sock inet;
58 #define udp_port_hash inet.sk.__sk_common.skc_u16hashes[0]
59 #define udp_portaddr_hash inet.sk.__sk_common.skc_u16hashes[1]
60 #define udp_portaddr_node inet.sk.__sk_common.skc_portaddr_node
61 int pending; /* Any pending frames ? */
62 unsigned int corkflag; /* Cork is required */
63 __u16 encap_type; /* Is this an Encapsulation socket? */
64 /*
65 * Following member retains the information to create a UDP header
66 * when the socket is uncorked.
67 */
68 __u16 len; /* total length of pending frames */
69 /*
70 * Fields specific to UDP-Lite.
71 */
72 __u16 pcslen;
73 __u16 pcrlen;
74 /* indicator bits used by pcflag: */
75 #define UDPLITE_BIT 0x1 /* set by udplite proto init function */
76 #define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */
77 #define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */
78 __u8 pcflag; /* marks socket as UDP-Lite if > 0 */
79 __u8 unused[3];
80 /*
81 * For encapsulation sockets.
82 */
83 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
84 };
85
udp_sk(const struct sock * sk)86 static inline struct udp_sock *udp_sk(const struct sock *sk)
87 {
88 return (struct udp_sock *)sk;
89 }
90
91 #define udp_portaddr_for_each_entry(__sk, node, list) \
92 hlist_nulls_for_each_entry(__sk, node, list, __sk_common.skc_portaddr_node)
93
94 #define udp_portaddr_for_each_entry_rcu(__sk, node, list) \
95 hlist_nulls_for_each_entry_rcu(__sk, node, list, __sk_common.skc_portaddr_node)
96
97 #define IS_UDPLITE(__sk) (udp_sk(__sk)->pcflag)
98
99 #endif
100
101 #endif /* _LINUX_UDP_H */
102