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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 <linux/bug.h>
27#include <net/inet_sock.h>
28#include <net/sock.h>
29#include <net/snmp.h>
30#include <net/ip.h>
31#include <linux/ipv6.h>
32#include <linux/seq_file.h>
33#include <linux/poll.h>
34
35/**
36 * struct udp_skb_cb - UDP(-Lite) private variables
37 *
38 * @header: private variables used by IPv4/IPv6
39 * @cscov: checksum coverage length (UDP-Lite only)
40 * @partial_cov: if set indicates partial csum coverage
41 */
42struct udp_skb_cb {
43 union {
44 struct inet_skb_parm h4;
45#if IS_ENABLED(CONFIG_IPV6)
46 struct inet6_skb_parm h6;
47#endif
48 } header;
49 __u16 cscov;
50 __u8 partial_cov;
51};
52#define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb))
53
54/**
55 * struct udp_hslot - UDP hash slot
56 *
57 * @head: head of list of sockets
58 * @count: number of sockets in 'head' list
59 * @lock: spinlock protecting changes to head/count
60 */
61struct udp_hslot {
62 struct hlist_nulls_head head;
63 int count;
64 spinlock_t lock;
65} __attribute__((aligned(2 * sizeof(long))));
66
67/**
68 * struct udp_table - UDP table
69 *
70 * @hash: hash table, sockets are hashed on (local port)
71 * @hash2: hash table, sockets are hashed on (local port, local address)
72 * @mask: number of slots in hash tables, minus 1
73 * @log: log2(number of slots in hash table)
74 */
75struct udp_table {
76 struct udp_hslot *hash;
77 struct udp_hslot *hash2;
78 unsigned int mask;
79 unsigned int log;
80};
81extern struct udp_table udp_table;
82void udp_table_init(struct udp_table *, const char *);
83static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
84 struct net *net, unsigned int num)
85{
86 return &table->hash[udp_hashfn(net, num, table->mask)];
87}
88/*
89 * For secondary hash, net_hash_mix() is performed before calling
90 * udp_hashslot2(), this explains difference with udp_hashslot()
91 */
92static inline struct udp_hslot *udp_hashslot2(struct udp_table *table,
93 unsigned int hash)
94{
95 return &table->hash2[hash & table->mask];
96}
97
98extern struct proto udp_prot;
99
100extern atomic_long_t udp_memory_allocated;
101
102/* sysctl variables for udp */
103extern long sysctl_udp_mem[3];
104extern int sysctl_udp_rmem_min;
105extern int sysctl_udp_wmem_min;
106
107struct sk_buff;
108
109/*
110 * Generic checksumming routines for UDP(-Lite) v4 and v6
111 */
112static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
113{
114 return (UDP_SKB_CB(skb)->cscov == skb->len ?
115 __skb_checksum_complete(skb) :
116 __skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov));
117}
118
119static inline int udp_lib_checksum_complete(struct sk_buff *skb)
120{
121 return !skb_csum_unnecessary(skb) &&
122 __udp_lib_checksum_complete(skb);
123}
124
125/**
126 * udp_csum_outgoing - compute UDPv4/v6 checksum over fragments
127 * @sk: socket we are writing to
128 * @skb: sk_buff containing the filled-in UDP header
129 * (checksum field must be zeroed out)
130 */
131static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
132{
133 __wsum csum = csum_partial(skb_transport_header(skb),
134 sizeof(struct udphdr), 0);
135 skb_queue_walk(&sk->sk_write_queue, skb) {
136 csum = csum_add(csum, skb->csum);
137 }
138 return csum;
139}
140
141static inline __wsum udp_csum(struct sk_buff *skb)
142{
143 __wsum csum = csum_partial(skb_transport_header(skb),
144 sizeof(struct udphdr), skb->csum);
145
146 for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next) {
147 csum = csum_add(csum, skb->csum);
148 }
149 return csum;
150}
151
152static inline __sum16 udp_v4_check(int len, __be32 saddr,
153 __be32 daddr, __wsum base)
154{
155 return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base);
156}
157
158void udp_set_csum(bool nocheck, struct sk_buff *skb,
159 __be32 saddr, __be32 daddr, int len);
160
161struct sk_buff **udp_gro_receive(struct sk_buff **head, struct sk_buff *skb,
162 struct udphdr *uh);
163int udp_gro_complete(struct sk_buff *skb, int nhoff);
164
165static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
166{
167 struct udphdr *uh;
168 unsigned int hlen, off;
169
170 off = skb_gro_offset(skb);
171 hlen = off + sizeof(*uh);
172 uh = skb_gro_header_fast(skb, off);
173 if (skb_gro_header_hard(skb, hlen))
174 uh = skb_gro_header_slow(skb, hlen, off);
175
176 return uh;
177}
178
179/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
180static inline int udp_lib_hash(struct sock *sk)
181{
182 BUG();
183 return 0;
184}
185
186void udp_lib_unhash(struct sock *sk);
187void udp_lib_rehash(struct sock *sk, u16 new_hash);
188
189static inline void udp_lib_close(struct sock *sk, long timeout)
190{
191 sk_common_release(sk);
192}
193
194int udp_lib_get_port(struct sock *sk, unsigned short snum,
195 int (*)(const struct sock *, const struct sock *, bool),
196 unsigned int hash2_nulladdr);
197
198u32 udp_flow_hashrnd(void);
199
200static inline __be16 udp_flow_src_port(struct net *net, struct sk_buff *skb,
201 int min, int max, bool use_eth)
202{
203 u32 hash;
204
205 if (min >= max) {
206 /* Use default range */
207 inet_get_local_port_range(net, &min, &max);
208 }
209
210 hash = skb_get_hash(skb);
211 if (unlikely(!hash)) {
212 if (use_eth) {
213 /* Can't find a normal hash, caller has indicated an
214 * Ethernet packet so use that to compute a hash.
215 */
216 hash = jhash(skb->data, 2 * ETH_ALEN,
217 (__force u32) skb->protocol);
218 } else {
219 /* Can't derive any sort of hash for the packet, set
220 * to some consistent random value.
221 */
222 hash = udp_flow_hashrnd();
223 }
224 }
225
226 /* Since this is being sent on the wire obfuscate hash a bit
227 * to minimize possbility that any useful information to an
228 * attacker is leaked. Only upper 16 bits are relevant in the
229 * computation for 16 bit port value.
230 */
231 hash ^= hash << 16;
232
233 return htons((((u64) hash * (max - min)) >> 32) + min);
234}
235
236/* net/ipv4/udp.c */
237void udp_v4_early_demux(struct sk_buff *skb);
238int udp_get_port(struct sock *sk, unsigned short snum,
239 int (*saddr_cmp)(const struct sock *,
240 const struct sock *));
241void udp_err(struct sk_buff *, u32);
242int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len);
243int udp_push_pending_frames(struct sock *sk);
244void udp_flush_pending_frames(struct sock *sk);
245void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst);
246int udp_rcv(struct sk_buff *skb);
247int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
248int udp_disconnect(struct sock *sk, int flags);
249unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait);
250struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb,
251 netdev_features_t features,
252 bool is_ipv6);
253int udp_lib_getsockopt(struct sock *sk, int level, int optname,
254 char __user *optval, int __user *optlen);
255int udp_lib_setsockopt(struct sock *sk, int level, int optname,
256 char __user *optval, unsigned int optlen,
257 int (*push_pending_frames)(struct sock *));
258struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
259 __be32 daddr, __be16 dport, int dif);
260struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
261 __be32 daddr, __be16 dport, int dif,
262 struct udp_table *tbl, struct sk_buff *skb);
263struct sock *udp6_lib_lookup(struct net *net,
264 const struct in6_addr *saddr, __be16 sport,
265 const struct in6_addr *daddr, __be16 dport,
266 int dif);
267struct sock *__udp6_lib_lookup(struct net *net,
268 const struct in6_addr *saddr, __be16 sport,
269 const struct in6_addr *daddr, __be16 dport,
270 int dif, struct udp_table *tbl,
271 struct sk_buff *skb);
272
273/*
274 * SNMP statistics for UDP and UDP-Lite
275 */
276#define UDP_INC_STATS_USER(net, field, is_udplite) do { \
277 if (is_udplite) SNMP_INC_STATS_USER((net)->mib.udplite_statistics, field); \
278 else SNMP_INC_STATS_USER((net)->mib.udp_statistics, field); } while(0)
279#define UDP_INC_STATS_BH(net, field, is_udplite) do { \
280 if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_statistics, field); \
281 else SNMP_INC_STATS_BH((net)->mib.udp_statistics, field); } while(0)
282
283#define UDP6_INC_STATS_BH(net, field, is_udplite) do { \
284 if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_stats_in6, field);\
285 else SNMP_INC_STATS_BH((net)->mib.udp_stats_in6, field); \
286} while(0)
287#define UDP6_INC_STATS_USER(net, field, __lite) do { \
288 if (__lite) SNMP_INC_STATS_USER((net)->mib.udplite_stats_in6, field); \
289 else SNMP_INC_STATS_USER((net)->mib.udp_stats_in6, field); \
290} while(0)
291
292#if IS_ENABLED(CONFIG_IPV6)
293#define UDPX_INC_STATS_BH(sk, field) \
294do { \
295 if ((sk)->sk_family == AF_INET) \
296 UDP_INC_STATS_BH(sock_net(sk), field, 0); \
297 else \
298 UDP6_INC_STATS_BH(sock_net(sk), field, 0); \
299} while (0)
300#else
301#define UDPX_INC_STATS_BH(sk, field) UDP_INC_STATS_BH(sock_net(sk), field, 0)
302#endif
303
304/* /proc */
305int udp_seq_open(struct inode *inode, struct file *file);
306
307struct udp_seq_afinfo {
308 char *name;
309 sa_family_t family;
310 struct udp_table *udp_table;
311 const struct file_operations *seq_fops;
312 struct seq_operations seq_ops;
313};
314
315struct udp_iter_state {
316 struct seq_net_private p;
317 sa_family_t family;
318 int bucket;
319 struct udp_table *udp_table;
320};
321
322#ifdef CONFIG_PROC_FS
323int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo);
324void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo);
325
326int udp4_proc_init(void);
327void udp4_proc_exit(void);
328#endif
329
330int udpv4_offload_init(void);
331
332void udp_init(void);
333
334void udp_encap_enable(void);
335#if IS_ENABLED(CONFIG_IPV6)
336void udpv6_encap_enable(void);
337#endif
338#endif /* _UDP_H */
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 <linux/bug.h>
27#include <net/inet_sock.h>
28#include <net/sock.h>
29#include <net/snmp.h>
30#include <net/ip.h>
31#include <linux/ipv6.h>
32#include <linux/seq_file.h>
33#include <linux/poll.h>
34
35/**
36 * struct udp_skb_cb - UDP(-Lite) private variables
37 *
38 * @header: private variables used by IPv4/IPv6
39 * @cscov: checksum coverage length (UDP-Lite only)
40 * @partial_cov: if set indicates partial csum coverage
41 */
42struct udp_skb_cb {
43 union {
44 struct inet_skb_parm h4;
45#if IS_ENABLED(CONFIG_IPV6)
46 struct inet6_skb_parm h6;
47#endif
48 } header;
49 __u16 cscov;
50 __u8 partial_cov;
51};
52#define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb))
53
54/**
55 * struct udp_hslot - UDP hash slot
56 *
57 * @head: head of list of sockets
58 * @count: number of sockets in 'head' list
59 * @lock: spinlock protecting changes to head/count
60 */
61struct udp_hslot {
62 struct hlist_nulls_head head;
63 int count;
64 spinlock_t lock;
65} __attribute__((aligned(2 * sizeof(long))));
66
67/**
68 * struct udp_table - UDP table
69 *
70 * @hash: hash table, sockets are hashed on (local port)
71 * @hash2: hash table, sockets are hashed on (local port, local address)
72 * @mask: number of slots in hash tables, minus 1
73 * @log: log2(number of slots in hash table)
74 */
75struct udp_table {
76 struct udp_hslot *hash;
77 struct udp_hslot *hash2;
78 unsigned int mask;
79 unsigned int log;
80};
81extern struct udp_table udp_table;
82extern void udp_table_init(struct udp_table *, const char *);
83static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
84 struct net *net, unsigned int num)
85{
86 return &table->hash[udp_hashfn(net, num, table->mask)];
87}
88/*
89 * For secondary hash, net_hash_mix() is performed before calling
90 * udp_hashslot2(), this explains difference with udp_hashslot()
91 */
92static inline struct udp_hslot *udp_hashslot2(struct udp_table *table,
93 unsigned int hash)
94{
95 return &table->hash2[hash & table->mask];
96}
97
98/* Note: this must match 'valbool' in sock_setsockopt */
99#define UDP_CSUM_NOXMIT 1
100
101/* Used by SunRPC/xprt layer. */
102#define UDP_CSUM_NORCV 2
103
104/* Default, as per the RFC, is to always do csums. */
105#define UDP_CSUM_DEFAULT 0
106
107extern struct proto udp_prot;
108
109extern atomic_long_t udp_memory_allocated;
110
111/* sysctl variables for udp */
112extern long sysctl_udp_mem[3];
113extern int sysctl_udp_rmem_min;
114extern int sysctl_udp_wmem_min;
115
116struct sk_buff;
117
118/*
119 * Generic checksumming routines for UDP(-Lite) v4 and v6
120 */
121static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
122{
123 return __skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov);
124}
125
126static inline int udp_lib_checksum_complete(struct sk_buff *skb)
127{
128 return !skb_csum_unnecessary(skb) &&
129 __udp_lib_checksum_complete(skb);
130}
131
132/**
133 * udp_csum_outgoing - compute UDPv4/v6 checksum over fragments
134 * @sk: socket we are writing to
135 * @skb: sk_buff containing the filled-in UDP header
136 * (checksum field must be zeroed out)
137 */
138static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
139{
140 __wsum csum = csum_partial(skb_transport_header(skb),
141 sizeof(struct udphdr), 0);
142 skb_queue_walk(&sk->sk_write_queue, skb) {
143 csum = csum_add(csum, skb->csum);
144 }
145 return csum;
146}
147
148static inline __wsum udp_csum(struct sk_buff *skb)
149{
150 __wsum csum = csum_partial(skb_transport_header(skb),
151 sizeof(struct udphdr), skb->csum);
152
153 for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next) {
154 csum = csum_add(csum, skb->csum);
155 }
156 return csum;
157}
158
159/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
160static inline void udp_lib_hash(struct sock *sk)
161{
162 BUG();
163}
164
165extern void udp_lib_unhash(struct sock *sk);
166extern void udp_lib_rehash(struct sock *sk, u16 new_hash);
167
168static inline void udp_lib_close(struct sock *sk, long timeout)
169{
170 sk_common_release(sk);
171}
172
173extern int udp_lib_get_port(struct sock *sk, unsigned short snum,
174 int (*)(const struct sock *,const struct sock *),
175 unsigned int hash2_nulladdr);
176
177/* net/ipv4/udp.c */
178extern int udp_get_port(struct sock *sk, unsigned short snum,
179 int (*saddr_cmp)(const struct sock *,
180 const struct sock *));
181extern void udp_err(struct sk_buff *, u32);
182extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk,
183 struct msghdr *msg, size_t len);
184extern void udp_flush_pending_frames(struct sock *sk);
185extern int udp_rcv(struct sk_buff *skb);
186extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
187extern int udp_disconnect(struct sock *sk, int flags);
188extern unsigned int udp_poll(struct file *file, struct socket *sock,
189 poll_table *wait);
190extern int udp_lib_getsockopt(struct sock *sk, int level, int optname,
191 char __user *optval, int __user *optlen);
192extern int udp_lib_setsockopt(struct sock *sk, int level, int optname,
193 char __user *optval, unsigned int optlen,
194 int (*push_pending_frames)(struct sock *));
195extern struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
196 __be32 daddr, __be16 dport,
197 int dif);
198extern struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
199 __be32 daddr, __be16 dport,
200 int dif, struct udp_table *tbl);
201extern struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
202 const struct in6_addr *daddr, __be16 dport,
203 int dif);
204extern struct sock *__udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
205 const struct in6_addr *daddr, __be16 dport,
206 int dif, struct udp_table *tbl);
207
208/*
209 * SNMP statistics for UDP and UDP-Lite
210 */
211#define UDP_INC_STATS_USER(net, field, is_udplite) do { \
212 if (is_udplite) SNMP_INC_STATS_USER((net)->mib.udplite_statistics, field); \
213 else SNMP_INC_STATS_USER((net)->mib.udp_statistics, field); } while(0)
214#define UDP_INC_STATS_BH(net, field, is_udplite) do { \
215 if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_statistics, field); \
216 else SNMP_INC_STATS_BH((net)->mib.udp_statistics, field); } while(0)
217
218#define UDP6_INC_STATS_BH(net, field, is_udplite) do { \
219 if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_stats_in6, field);\
220 else SNMP_INC_STATS_BH((net)->mib.udp_stats_in6, field); \
221} while(0)
222#define UDP6_INC_STATS_USER(net, field, __lite) do { \
223 if (__lite) SNMP_INC_STATS_USER((net)->mib.udplite_stats_in6, field); \
224 else SNMP_INC_STATS_USER((net)->mib.udp_stats_in6, field); \
225} while(0)
226
227#if IS_ENABLED(CONFIG_IPV6)
228#define UDPX_INC_STATS_BH(sk, field) \
229 do { \
230 if ((sk)->sk_family == AF_INET) \
231 UDP_INC_STATS_BH(sock_net(sk), field, 0); \
232 else \
233 UDP6_INC_STATS_BH(sock_net(sk), field, 0); \
234 } while (0);
235#else
236#define UDPX_INC_STATS_BH(sk, field) UDP_INC_STATS_BH(sock_net(sk), field, 0)
237#endif
238
239/* /proc */
240int udp_seq_open(struct inode *inode, struct file *file);
241
242struct udp_seq_afinfo {
243 char *name;
244 sa_family_t family;
245 struct udp_table *udp_table;
246 const struct file_operations *seq_fops;
247 struct seq_operations seq_ops;
248};
249
250struct udp_iter_state {
251 struct seq_net_private p;
252 sa_family_t family;
253 int bucket;
254 struct udp_table *udp_table;
255};
256
257#ifdef CONFIG_PROC_FS
258extern int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo);
259extern void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo);
260
261extern int udp4_proc_init(void);
262extern void udp4_proc_exit(void);
263#endif
264
265extern void udp_init(void);
266
267extern int udp4_ufo_send_check(struct sk_buff *skb);
268extern struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb,
269 netdev_features_t features);
270extern void udp_encap_enable(void);
271#if IS_ENABLED(CONFIG_IPV6)
272extern void udpv6_encap_enable(void);
273#endif
274#endif /* _UDP_H */