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.
6 * Definitions for the UDP module.
8 * Version: @(#)udp.h 1.0.2 05/07/93
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
14 * Alan Cox : Turned on udp checksums. I don't want to
15 * chase 'memory corruption' bugs that aren't!
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.
25 #include <linux/list.h>
26 #include <net/inet_sock.h>
30 #include <linux/ipv6.h>
31 #include <linux/seq_file.h>
32 #include <linux/poll.h>
35 * struct udp_skb_cb - UDP(-Lite) private variables
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
43 struct inet_skb_parm h4;
44 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
45 struct inet6_skb_parm h6;
51 #define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb))
53 extern struct hlist_head udp_hash[UDP_HTABLE_SIZE];
54 extern rwlock_t udp_hash_lock;
57 /* Note: this must match 'valbool' in sock_setsockopt */
58 #define UDP_CSUM_NOXMIT 1
60 /* Used by SunRPC/xprt layer. */
61 #define UDP_CSUM_NORCV 2
63 /* Default, as per the RFC, is to always do csums. */
64 #define UDP_CSUM_DEFAULT 0
66 extern struct proto udp_prot;
71 * Generic checksumming routines for UDP(-Lite) v4 and v6
73 static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
75 if (! UDP_SKB_CB(skb)->partial_cov)
76 return __skb_checksum_complete(skb);
77 return csum_fold(skb_checksum(skb, 0, UDP_SKB_CB(skb)->cscov,
81 static inline int udp_lib_checksum_complete(struct sk_buff *skb)
83 return skb->ip_summed != CHECKSUM_UNNECESSARY &&
84 __udp_lib_checksum_complete(skb);
88 * udp_csum_outgoing - compute UDPv4/v6 checksum over fragments
89 * @sk: socket we are writing to
90 * @skb: sk_buff containing the filled-in UDP header
91 * (checksum field must be zeroed out)
93 static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
95 __wsum csum = csum_partial(skb->h.raw, sizeof(struct udphdr), 0);
97 skb_queue_walk(&sk->sk_write_queue, skb) {
98 csum = csum_add(csum, skb->csum);
103 /* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
104 static inline void udp_lib_hash(struct sock *sk)
109 static inline void udp_lib_unhash(struct sock *sk)
111 write_lock_bh(&udp_hash_lock);
112 if (sk_del_node_init(sk)) {
113 inet_sk(sk)->num = 0;
114 sock_prot_dec_use(sk->sk_prot);
116 write_unlock_bh(&udp_hash_lock);
119 static inline void udp_lib_close(struct sock *sk, long timeout)
121 sk_common_release(sk);
126 extern int udp_get_port(struct sock *sk, unsigned short snum,
127 int (*saddr_cmp)(const struct sock *, const struct sock *));
128 extern void udp_err(struct sk_buff *, u32);
130 extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk,
131 struct msghdr *msg, size_t len);
133 extern int udp_rcv(struct sk_buff *skb);
134 extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
135 extern int udp_disconnect(struct sock *sk, int flags);
136 extern unsigned int udp_poll(struct file *file, struct socket *sock,
138 extern int udp_lib_getsockopt(struct sock *sk, int level, int optname,
139 char __user *optval, int __user *optlen);
140 extern int udp_lib_setsockopt(struct sock *sk, int level, int optname,
141 char __user *optval, int optlen,
142 int (*push_pending_frames)(struct sock *));
144 DECLARE_SNMP_STAT(struct udp_mib, udp_statistics);
146 * SNMP statistics for UDP and UDP-Lite
148 #define UDP_INC_STATS_USER(field, is_udplite) do { \
149 if (is_udplite) SNMP_INC_STATS_USER(udplite_statistics, field); \
150 else SNMP_INC_STATS_USER(udp_statistics, field); } while(0)
151 #define UDP_INC_STATS_BH(field, is_udplite) do { \
152 if (is_udplite) SNMP_INC_STATS_BH(udplite_statistics, field); \
153 else SNMP_INC_STATS_BH(udp_statistics, field); } while(0)
156 struct udp_seq_afinfo {
157 struct module *owner;
160 struct hlist_head *hashtable;
161 int (*seq_show) (struct seq_file *m, void *v);
162 struct file_operations *seq_fops;
165 struct udp_iter_state {
167 struct hlist_head *hashtable;
169 struct seq_operations seq_ops;
172 #ifdef CONFIG_PROC_FS
173 extern int udp_proc_register(struct udp_seq_afinfo *afinfo);
174 extern void udp_proc_unregister(struct udp_seq_afinfo *afinfo);
176 extern int udp4_proc_init(void);
177 extern void udp4_proc_exit(void);