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 <net/inet_sock.h>
21 #include <linux/skbuff.h>
22 #include <net/netns/hash.h>
23 #include <uapi/linux/udp.h>
24
udp_hdr(const struct sk_buff * skb)25 static inline struct udphdr *udp_hdr(const struct sk_buff *skb)
26 {
27 return (struct udphdr *)skb_transport_header(skb);
28 }
29
inner_udp_hdr(const struct sk_buff * skb)30 static inline struct udphdr *inner_udp_hdr(const struct sk_buff *skb)
31 {
32 return (struct udphdr *)skb_inner_transport_header(skb);
33 }
34
35 #define UDP_HTABLE_SIZE_MIN (CONFIG_BASE_SMALL ? 128 : 256)
36
udp_hashfn(const struct net * net,u32 num,u32 mask)37 static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask)
38 {
39 return (num + net_hash_mix(net)) & mask;
40 }
41
42 struct udp_sock {
43 /* inet_sock has to be the first member */
44 struct inet_sock inet;
45 #define udp_port_hash inet.sk.__sk_common.skc_u16hashes[0]
46 #define udp_portaddr_hash inet.sk.__sk_common.skc_u16hashes[1]
47 #define udp_portaddr_node inet.sk.__sk_common.skc_portaddr_node
48 int pending; /* Any pending frames ? */
49 unsigned int corkflag; /* Cork is required */
50 __u8 encap_type; /* Is this an Encapsulation socket? */
51 unsigned char no_check6_tx:1,/* Send zero UDP6 checksums on TX? */
52 no_check6_rx:1;/* Allow zero UDP6 checksums on RX? */
53 /*
54 * Following member retains the information to create a UDP header
55 * when the socket is uncorked.
56 */
57 __u16 len; /* total length of pending frames */
58 __u16 gso_size;
59 /*
60 * Fields specific to UDP-Lite.
61 */
62 __u16 pcslen;
63 __u16 pcrlen;
64 /* indicator bits used by pcflag: */
65 #define UDPLITE_BIT 0x1 /* set by udplite proto init function */
66 #define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */
67 #define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */
68 __u8 pcflag; /* marks socket as UDP-Lite if > 0 */
69 __u8 unused[3];
70 /*
71 * For encapsulation sockets.
72 */
73 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
74 void (*encap_destroy)(struct sock *sk);
75
76 /* GRO functions for UDP socket */
77 struct sk_buff * (*gro_receive)(struct sock *sk,
78 struct list_head *head,
79 struct sk_buff *skb);
80 int (*gro_complete)(struct sock *sk,
81 struct sk_buff *skb,
82 int nhoff);
83
84 /* udp_recvmsg try to use this before splicing sk_receive_queue */
85 struct sk_buff_head reader_queue ____cacheline_aligned_in_smp;
86
87 /* This field is dirtied by udp_recvmsg() */
88 int forward_deficit;
89 };
90
91 #define UDP_MAX_SEGMENTS (1 << 6UL)
92
udp_sk(const struct sock * sk)93 static inline struct udp_sock *udp_sk(const struct sock *sk)
94 {
95 return (struct udp_sock *)sk;
96 }
97
udp_set_no_check6_tx(struct sock * sk,bool val)98 static inline void udp_set_no_check6_tx(struct sock *sk, bool val)
99 {
100 udp_sk(sk)->no_check6_tx = val;
101 }
102
udp_set_no_check6_rx(struct sock * sk,bool val)103 static inline void udp_set_no_check6_rx(struct sock *sk, bool val)
104 {
105 udp_sk(sk)->no_check6_rx = val;
106 }
107
udp_get_no_check6_tx(struct sock * sk)108 static inline bool udp_get_no_check6_tx(struct sock *sk)
109 {
110 return udp_sk(sk)->no_check6_tx;
111 }
112
udp_get_no_check6_rx(struct sock * sk)113 static inline bool udp_get_no_check6_rx(struct sock *sk)
114 {
115 return udp_sk(sk)->no_check6_rx;
116 }
117
118 #define udp_portaddr_for_each_entry(__sk, list) \
119 hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node)
120
121 #define udp_portaddr_for_each_entry_rcu(__sk, list) \
122 hlist_for_each_entry_rcu(__sk, list, __sk_common.skc_portaddr_node)
123
124 #define IS_UDPLITE(__sk) (__sk->sk_protocol == IPPROTO_UDPLITE)
125
126 #endif /* _LINUX_UDP_H */
127