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 25 static inline struct udphdr *udp_hdr(const struct sk_buff *skb) 26 { 27 return (struct udphdr *)skb_transport_header(skb); 28 } 29 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 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 93 static inline struct udp_sock *udp_sk(const struct sock *sk) 94 { 95 return (struct udp_sock *)sk; 96 } 97 98 static inline void udp_set_no_check6_tx(struct sock *sk, bool val) 99 { 100 udp_sk(sk)->no_check6_tx = val; 101 } 102 103 static inline void udp_set_no_check6_rx(struct sock *sk, bool val) 104 { 105 udp_sk(sk)->no_check6_rx = val; 106 } 107 108 static inline bool udp_get_no_check6_tx(struct sock *sk) 109 { 110 return udp_sk(sk)->no_check6_tx; 111 } 112 113 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