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 struct udp_hslot {
54 struct hlist_nulls_head head;
55 spinlock_t lock;
56 } __attribute__((aligned(2 * sizeof(long))));
57 struct udp_table {
58 struct udp_hslot hash[UDP_HTABLE_SIZE];
59 };
60 extern struct udp_table udp_table;
61 extern void udp_table_init(struct udp_table *);
62
63
64 /* Note: this must match 'valbool' in sock_setsockopt */
65 #define UDP_CSUM_NOXMIT 1
66
67 /* Used by SunRPC/xprt layer. */
68 #define UDP_CSUM_NORCV 2
69
70 /* Default, as per the RFC, is to always do csums. */
71 #define UDP_CSUM_DEFAULT 0
72
73 extern struct proto udp_prot;
74
75 extern atomic_t udp_memory_allocated;
76
77 /* sysctl variables for udp */
78 extern int sysctl_udp_mem[3];
79 extern int sysctl_udp_rmem_min;
80 extern int sysctl_udp_wmem_min;
81
82 struct sk_buff;
83
84 /*
85 * Generic checksumming routines for UDP(-Lite) v4 and v6
86 */
__udp_lib_checksum_complete(struct sk_buff * skb)87 static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
88 {
89 return __skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov);
90 }
91
udp_lib_checksum_complete(struct sk_buff * skb)92 static inline int udp_lib_checksum_complete(struct sk_buff *skb)
93 {
94 return !skb_csum_unnecessary(skb) &&
95 __udp_lib_checksum_complete(skb);
96 }
97
98 /**
99 * udp_csum_outgoing - compute UDPv4/v6 checksum over fragments
100 * @sk: socket we are writing to
101 * @skb: sk_buff containing the filled-in UDP header
102 * (checksum field must be zeroed out)
103 */
udp_csum_outgoing(struct sock * sk,struct sk_buff * skb)104 static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
105 {
106 __wsum csum = csum_partial(skb_transport_header(skb),
107 sizeof(struct udphdr), 0);
108 skb_queue_walk(&sk->sk_write_queue, skb) {
109 csum = csum_add(csum, skb->csum);
110 }
111 return csum;
112 }
113
114 /* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
udp_lib_hash(struct sock * sk)115 static inline void udp_lib_hash(struct sock *sk)
116 {
117 BUG();
118 }
119
120 extern void udp_lib_unhash(struct sock *sk);
121
udp_lib_close(struct sock * sk,long timeout)122 static inline void udp_lib_close(struct sock *sk, long timeout)
123 {
124 sk_common_release(sk);
125 }
126
127 extern int udp_lib_get_port(struct sock *sk, unsigned short snum,
128 int (*)(const struct sock*,const struct sock*));
129
130 /* net/ipv4/udp.c */
131 extern int udp_get_port(struct sock *sk, unsigned short snum,
132 int (*saddr_cmp)(const struct sock *, const struct sock *));
133 extern void udp_err(struct sk_buff *, u32);
134
135 extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk,
136 struct msghdr *msg, size_t len);
137 extern void udp_flush_pending_frames(struct sock *sk);
138
139 extern int udp_rcv(struct sk_buff *skb);
140 extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
141 extern int udp_disconnect(struct sock *sk, int flags);
142 extern unsigned int udp_poll(struct file *file, struct socket *sock,
143 poll_table *wait);
144 extern int udp_lib_getsockopt(struct sock *sk, int level, int optname,
145 char __user *optval, int __user *optlen);
146 extern int udp_lib_setsockopt(struct sock *sk, int level, int optname,
147 char __user *optval, int optlen,
148 int (*push_pending_frames)(struct sock *));
149
150 extern struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
151 __be32 daddr, __be16 dport,
152 int dif);
153
154 /*
155 * SNMP statistics for UDP and UDP-Lite
156 */
157 #define UDP_INC_STATS_USER(net, field, is_udplite) do { \
158 if (is_udplite) SNMP_INC_STATS_USER((net)->mib.udplite_statistics, field); \
159 else SNMP_INC_STATS_USER((net)->mib.udp_statistics, field); } while(0)
160 #define UDP_INC_STATS_BH(net, field, is_udplite) do { \
161 if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_statistics, field); \
162 else SNMP_INC_STATS_BH((net)->mib.udp_statistics, field); } while(0)
163
164 #define UDP6_INC_STATS_BH(net, field, is_udplite) do { \
165 if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_stats_in6, field);\
166 else SNMP_INC_STATS_BH((net)->mib.udp_stats_in6, field); \
167 } while(0)
168 #define UDP6_INC_STATS_USER(net, field, __lite) do { \
169 if (__lite) SNMP_INC_STATS_USER((net)->mib.udplite_stats_in6, field); \
170 else SNMP_INC_STATS_USER((net)->mib.udp_stats_in6, field); \
171 } while(0)
172
173 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
174 #define UDPX_INC_STATS_BH(sk, field) \
175 do { \
176 if ((sk)->sk_family == AF_INET) \
177 UDP_INC_STATS_BH(sock_net(sk), field, 0); \
178 else \
179 UDP6_INC_STATS_BH(sock_net(sk), field, 0); \
180 } while (0);
181 #else
182 #define UDPX_INC_STATS_BH(sk, field) UDP_INC_STATS_BH(sock_net(sk), field, 0)
183 #endif
184
185 /* /proc */
186 struct udp_seq_afinfo {
187 char *name;
188 sa_family_t family;
189 struct udp_table *udp_table;
190 struct file_operations seq_fops;
191 struct seq_operations seq_ops;
192 };
193
194 struct udp_iter_state {
195 struct seq_net_private p;
196 sa_family_t family;
197 int bucket;
198 struct udp_table *udp_table;
199 };
200
201 #ifdef CONFIG_PROC_FS
202 extern int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo);
203 extern void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo);
204
205 extern int udp4_proc_init(void);
206 extern void udp4_proc_exit(void);
207 #endif
208
209 extern void udp_init(void);
210 #endif /* _UDP_H */
211