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 module. 7 * 8 * Version: @(#)udp.h 1.0.2 05/07/93 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * 13 * Fixes: 14 * Alan Cox : Turned on udp checksums. I don't want to 15 * chase 'memory corruption' bugs that aren't! 16 * 17 * This program is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU General Public License 19 * as published by the Free Software Foundation; either version 20 * 2 of the License, or (at your option) any later version. 21 */ 22#ifndef _UDP_H 23#define _UDP_H 24 25#include <linux/list.h> 26#include <net/inet_sock.h> 27#include <net/sock.h> 28#include <net/snmp.h> 29#include <net/ip.h> 30#include <linux/ipv6.h> 31#include <linux/seq_file.h> 32#include <linux/poll.h> 33 34/** 35 * struct udp_skb_cb - UDP(-Lite) private variables 36 * 37 * @header: private variables used by IPv4/IPv6 38 * @cscov: checksum coverage length (UDP-Lite only) 39 * @partial_cov: if set indicates partial csum coverage 40 */ 41struct udp_skb_cb { 42 union { 43 struct inet_skb_parm h4; 44#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 45 struct inet6_skb_parm h6; 46#endif 47 } header; 48 __u16 cscov; 49 __u8 partial_cov; 50}; 51#define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb)) 52 53extern struct hlist_head udp_hash[UDP_HTABLE_SIZE]; 54extern rwlock_t udp_hash_lock; 55 56 57/* Note: this must match 'valbool' in sock_setsockopt */ 58#define UDP_CSUM_NOXMIT 1 59 60/* Used by SunRPC/xprt layer. */ 61#define UDP_CSUM_NORCV 2 62 63/* Default, as per the RFC, is to always do csums. */ 64#define UDP_CSUM_DEFAULT 0 65 66extern struct proto udp_prot; 67 68struct sk_buff; 69 70/* 71 * Generic checksumming routines for UDP(-Lite) v4 and v6 72 */ 73static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb) 74{ 75 return __skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov); 76} 77 78static inline int udp_lib_checksum_complete(struct sk_buff *skb) 79{ 80 return !skb_csum_unnecessary(skb) && 81 __udp_lib_checksum_complete(skb); 82} 83 84/** 85 * udp_csum_outgoing - compute UDPv4/v6 checksum over fragments 86 * @sk: socket we are writing to 87 * @skb: sk_buff containing the filled-in UDP header 88 * (checksum field must be zeroed out) 89 */ 90static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb) 91{ 92 __wsum csum = csum_partial(skb_transport_header(skb), 93 sizeof(struct udphdr), 0); 94 skb_queue_walk(&sk->sk_write_queue, skb) { 95 csum = csum_add(csum, skb->csum); 96 } 97 return csum; 98} 99 100/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */ 101static inline void udp_lib_hash(struct sock *sk) 102{ 103 BUG(); 104} 105 106static inline void udp_lib_unhash(struct sock *sk) 107{ 108 write_lock_bh(&udp_hash_lock); 109 if (sk_del_node_init(sk)) { 110 inet_sk(sk)->num = 0; 111 sock_prot_dec_use(sk->sk_prot); 112 } 113 write_unlock_bh(&udp_hash_lock); 114} 115 116static inline void udp_lib_close(struct sock *sk, long timeout) 117{ 118 sk_common_release(sk); 119} 120 121 122/* net/ipv4/udp.c */ 123extern int udp_get_port(struct sock *sk, unsigned short snum, 124 int (*saddr_cmp)(const struct sock *, const struct sock *)); 125extern void udp_err(struct sk_buff *, u32); 126 127extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk, 128 struct msghdr *msg, size_t len); 129 130extern int udp_rcv(struct sk_buff *skb); 131extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg); 132extern int udp_disconnect(struct sock *sk, int flags); 133extern unsigned int udp_poll(struct file *file, struct socket *sock, 134 poll_table *wait); 135extern int udp_lib_getsockopt(struct sock *sk, int level, int optname, 136 char __user *optval, int __user *optlen); 137extern int udp_lib_setsockopt(struct sock *sk, int level, int optname, 138 char __user *optval, int optlen, 139 int (*push_pending_frames)(struct sock *)); 140 141DECLARE_SNMP_STAT(struct udp_mib, udp_statistics); 142/* 143 * SNMP statistics for UDP and UDP-Lite 144 */ 145#define UDP_INC_STATS_USER(field, is_udplite) do { \ 146 if (is_udplite) SNMP_INC_STATS_USER(udplite_statistics, field); \ 147 else SNMP_INC_STATS_USER(udp_statistics, field); } while(0) 148#define UDP_INC_STATS_BH(field, is_udplite) do { \ 149 if (is_udplite) SNMP_INC_STATS_BH(udplite_statistics, field); \ 150 else SNMP_INC_STATS_BH(udp_statistics, field); } while(0) 151 152/* /proc */ 153struct udp_seq_afinfo { 154 struct module *owner; 155 char *name; 156 sa_family_t family; 157 struct hlist_head *hashtable; 158 int (*seq_show) (struct seq_file *m, void *v); 159 struct file_operations *seq_fops; 160}; 161 162struct udp_iter_state { 163 sa_family_t family; 164 struct hlist_head *hashtable; 165 int bucket; 166 struct seq_operations seq_ops; 167}; 168 169#ifdef CONFIG_PROC_FS 170extern int udp_proc_register(struct udp_seq_afinfo *afinfo); 171extern void udp_proc_unregister(struct udp_seq_afinfo *afinfo); 172 173extern int udp4_proc_init(void); 174extern void udp4_proc_exit(void); 175#endif 176#endif /* _UDP_H */ 177