summaryrefslogtreecommitdiff
path: root/include/net/udp.h
blob: 1ffb39c9f324ccd05211460672b80b592043cf7a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		Definitions for the UDP module.
 *
 * Version:	@(#)udp.h	1.0.2	05/07/93
 *
 * Authors:	Ross Biro
 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *
 * Fixes:
 *		Alan Cox	: Turned on udp checksums. I don't want to
 *				  chase 'memory corruption' bugs that aren't!
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 */
#ifndef _UDP_H
#define _UDP_H

#include <linux/list.h>
#include <net/inet_sock.h>
#include <net/sock.h>
#include <net/snmp.h>
#include <net/ip.h>
#include <linux/ipv6.h>
#include <linux/seq_file.h>
#include <linux/poll.h>

/**
 *	struct udp_skb_cb  -  UDP(-Lite) private variables
 *
 *	@header:      private variables used by IPv4/IPv6
 *	@cscov:       checksum coverage length (UDP-Lite only)
 *	@partial_cov: if set indicates partial csum coverage
 */
struct udp_skb_cb {
	union {
		struct inet_skb_parm	h4;
#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
		struct inet6_skb_parm	h6;
#endif
	} header;
	__u16		cscov;
	__u8		partial_cov;
};
#define UDP_SKB_CB(__skb)	((struct udp_skb_cb *)((__skb)->cb))

/**
 *	struct udp_hslot - UDP hash slot
 *
 *	@head:	head of list of sockets
 *	@count:	number of sockets in 'head' list
 *	@lock:	spinlock protecting changes to head/count
 */
struct udp_hslot {
	struct hlist_nulls_head	head;
	int			count;
	spinlock_t		lock;
} __attribute__((aligned(2 * sizeof(long))));

/**
 *	struct udp_table - UDP table
 *
 *	@hash:	hash table, sockets are hashed on (local port)
 *	@hash2:	hash table, sockets are hashed on (local port, local address)
 *	@mask:	number of slots in hash tables, minus 1
 *	@log:	log2(number of slots in hash table)
 */
struct udp_table {
	struct udp_hslot	*hash;
	struct udp_hslot	*hash2;
	unsigned int		mask;
	unsigned int		log;
};
extern struct udp_table udp_table;
extern void udp_table_init(struct udp_table *, const char *);
static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
					     struct net *net, unsigned num)
{
	return &table->hash[udp_hashfn(net, num, table->mask)];
}
/*
 * For secondary hash, net_hash_mix() is performed before calling
 * udp_hashslot2(), this explains difference with udp_hashslot()
 */
static inline struct udp_hslot *udp_hashslot2(struct udp_table *table,
					      unsigned int hash)
{
	return &table->hash2[hash & table->mask];
}

/* Note: this must match 'valbool' in sock_setsockopt */
#define UDP_CSUM_NOXMIT		1

/* Used by SunRPC/xprt layer. */
#define UDP_CSUM_NORCV		2

/* Default, as per the RFC, is to always do csums. */
#define UDP_CSUM_DEFAULT	0

extern struct proto udp_prot;

extern atomic_long_t udp_memory_allocated;

/* sysctl variables for udp */
extern long sysctl_udp_mem[3];
extern int sysctl_udp_rmem_min;
extern int sysctl_udp_wmem_min;

struct sk_buff;

/*
 *	Generic checksumming routines for UDP(-Lite) v4 and v6
 */
static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
{
	return __skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov);
}

static inline int udp_lib_checksum_complete(struct sk_buff *skb)
{
	return !skb_csum_unnecessary(skb) &&
		__udp_lib_checksum_complete(skb);
}

/**
 * 	udp_csum_outgoing  -  compute UDPv4/v6 checksum over fragments
 * 	@sk: 	socket we are writing to
 * 	@skb: 	sk_buff containing the filled-in UDP header
 * 	        (checksum field must be zeroed out)
 */
static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
{
	__wsum csum = csum_partial(skb_transport_header(skb),
				   sizeof(struct udphdr), 0);
	skb_queue_walk(&sk->sk_write_queue, skb) {
		csum = csum_add(csum, skb->csum);
	}
	return csum;
}

static inline __wsum udp_csum(struct sk_buff *skb)
{
	__wsum csum = csum_partial(skb_transport_header(skb),
				   sizeof(struct udphdr), skb->csum);

	for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next) {
		csum = csum_add(csum, skb->csum);
	}
	return csum;
}

/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
static inline void udp_lib_hash(struct sock *sk)
{
	BUG();
}

extern void udp_lib_unhash(struct sock *sk);
extern void udp_lib_rehash(struct sock *sk, u16 new_hash);

static inline void udp_lib_close(struct sock *sk, long timeout)
{
	sk_common_release(sk);
}

extern int udp_lib_get_port(struct sock *sk, unsigned short snum,
			    int (*)(const struct sock *,const struct sock *),
			    unsigned int hash2_nulladdr);

/* net/ipv4/udp.c */
extern int udp_get_port(struct sock *sk, unsigned short snum,
			int (*saddr_cmp)(const struct sock *,
					 const struct sock *));
extern void udp_err(struct sk_buff *, u32);
extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk,
			    struct msghdr *msg, size_t len);
extern void udp_flush_pending_frames(struct sock *sk);
extern int udp_rcv(struct sk_buff *skb);
extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
extern int udp_disconnect(struct sock *sk, int flags);
extern unsigned int udp_poll(struct file *file, struct socket *sock,
			     poll_table *wait);
extern int udp_lib_getsockopt(struct sock *sk, int level, int optname,
			      char __user *optval, int __user *optlen);
extern int udp_lib_setsockopt(struct sock *sk, int level, int optname,
			      char __user *optval, unsigned int optlen,
			      int (*push_pending_frames)(struct sock *));
extern struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
				    __be32 daddr, __be16 dport,
				    int dif);
extern struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
				    __be32 daddr, __be16 dport,
				    int dif, struct udp_table *tbl);
extern struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
				    const struct in6_addr *daddr, __be16 dport,
				    int dif);
extern struct sock *__udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
				    const struct in6_addr *daddr, __be16 dport,
				    int dif, struct udp_table *tbl);

/*
 * 	SNMP statistics for UDP and UDP-Lite
 */
#define UDP_INC_STATS_USER(net, field, is_udplite)	      do { \
	if (is_udplite) SNMP_INC_STATS_USER((net)->mib.udplite_statistics, field);       \
	else		SNMP_INC_STATS_USER((net)->mib.udp_statistics, field);  }  while(0)
#define UDP_INC_STATS_BH(net, field, is_udplite) 	      do { \
	if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_statistics, field);         \
	else		SNMP_INC_STATS_BH((net)->mib.udp_statistics, field);    }  while(0)

#define UDP6_INC_STATS_BH(net, field, is_udplite) 	    do { \
	if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_stats_in6, field);\
	else		SNMP_INC_STATS_BH((net)->mib.udp_stats_in6, field);  \
} while(0)
#define UDP6_INC_STATS_USER(net, field, __lite)		    do { \
	if (__lite) SNMP_INC_STATS_USER((net)->mib.udplite_stats_in6, field);  \
	else	    SNMP_INC_STATS_USER((net)->mib.udp_stats_in6, field);      \
} while(0)

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
#define UDPX_INC_STATS_BH(sk, field) \
	do { \
		if ((sk)->sk_family == AF_INET) \
			UDP_INC_STATS_BH(sock_net(sk), field, 0); \
		else \
			UDP6_INC_STATS_BH(sock_net(sk), field, 0); \
	} while (0);
#else
#define UDPX_INC_STATS_BH(sk, field) UDP_INC_STATS_BH(sock_net(sk), field, 0)
#endif

/* /proc */
int udp_seq_open(struct inode *inode, struct file *file);

struct udp_seq_afinfo {
	char				*name;
	sa_family_t			family;
	struct udp_table		*udp_table;
	const struct file_operations	*seq_fops;
	struct seq_operations		seq_ops;
};

struct udp_iter_state {
	struct seq_net_private  p;
	sa_family_t		family;
	int			bucket;
	struct udp_table	*udp_table;
};

#ifdef CONFIG_PROC_FS
extern int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo);
extern void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo);

extern int udp4_proc_init(void);
extern void udp4_proc_exit(void);
#endif

extern void udp_init(void);

extern int udp4_ufo_send_check(struct sk_buff *skb);
extern struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb,
	netdev_features_t features);
#endif	/* _UDP_H */