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 */ 41 struct 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 53 extern struct hlist_head udp_hash[UDP_HTABLE_SIZE]; 54 extern 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 66 extern struct proto udp_prot; 67 68 struct sk_buff; 69 70 /* 71 * Generic checksumming routines for UDP(-Lite) v4 and v6 72 */ 73 static 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 78 static 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 */ 90 static 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 */ 101 static inline void udp_lib_hash(struct sock *sk) 102 { 103 BUG(); 104 } 105 106 static 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 } 115 116 static inline void udp_lib_close(struct sock *sk, long timeout) 117 { 118 sk_common_release(sk); 119 } 120 121 122 struct udp_get_port_ops { 123 int (*saddr_cmp)(const struct sock *sk1, const struct sock *sk2); 124 int (*saddr_any)(const struct sock *sk); 125 unsigned int (*hash_port_and_rcv_saddr)(__u16 port, 126 const struct sock *sk); 127 }; 128 129 /* net/ipv4/udp.c */ 130 extern int udp_get_port(struct sock *sk, unsigned short snum, 131 const struct udp_get_port_ops *ops); 132 extern void udp_err(struct sk_buff *, u32); 133 134 extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk, 135 struct msghdr *msg, size_t len); 136 137 extern int udp_rcv(struct sk_buff *skb); 138 extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg); 139 extern int udp_disconnect(struct sock *sk, int flags); 140 extern unsigned int udp_poll(struct file *file, struct socket *sock, 141 poll_table *wait); 142 extern int udp_lib_getsockopt(struct sock *sk, int level, int optname, 143 char __user *optval, int __user *optlen); 144 extern int udp_lib_setsockopt(struct sock *sk, int level, int optname, 145 char __user *optval, int optlen, 146 int (*push_pending_frames)(struct sock *)); 147 148 DECLARE_SNMP_STAT(struct udp_mib, udp_statistics); 149 /* 150 * SNMP statistics for UDP and UDP-Lite 151 */ 152 #define UDP_INC_STATS_USER(field, is_udplite) do { \ 153 if (is_udplite) SNMP_INC_STATS_USER(udplite_statistics, field); \ 154 else SNMP_INC_STATS_USER(udp_statistics, field); } while(0) 155 #define UDP_INC_STATS_BH(field, is_udplite) do { \ 156 if (is_udplite) SNMP_INC_STATS_BH(udplite_statistics, field); \ 157 else SNMP_INC_STATS_BH(udp_statistics, field); } while(0) 158 159 /* /proc */ 160 struct udp_seq_afinfo { 161 struct module *owner; 162 char *name; 163 sa_family_t family; 164 struct hlist_head *hashtable; 165 int (*seq_show) (struct seq_file *m, void *v); 166 struct file_operations *seq_fops; 167 }; 168 169 struct udp_iter_state { 170 sa_family_t family; 171 struct hlist_head *hashtable; 172 int bucket; 173 struct seq_operations seq_ops; 174 }; 175 176 #ifdef CONFIG_PROC_FS 177 extern int udp_proc_register(struct udp_seq_afinfo *afinfo); 178 extern void udp_proc_unregister(struct udp_seq_afinfo *afinfo); 179 180 extern int udp4_proc_init(void); 181 extern void udp4_proc_exit(void); 182 #endif 183 #endif /* _UDP_H */ 184