~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/include/net/udp.h

Version: ~ [ linux-5.4-rc7 ] ~ [ linux-5.3.10 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.83 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.153 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.200 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.200 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.76 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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  */
 42 struct 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  */
 61 struct udp_hslot {
 62         struct hlist_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  */
 75 struct udp_table {
 76         struct udp_hslot        *hash;
 77         struct udp_hslot        *hash2;
 78         unsigned int            mask;
 79         unsigned int            log;
 80 };
 81 extern struct udp_table udp_table;
 82 void udp_table_init(struct udp_table *, const char *);
 83 static 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  */
 92 static 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 extern struct proto udp_prot;
 99 
100 extern atomic_long_t udp_memory_allocated;
101 
102 /* sysctl variables for udp */
103 extern long sysctl_udp_mem[3];
104 extern int sysctl_udp_rmem_min;
105 extern int sysctl_udp_wmem_min;
106 
107 struct sk_buff;
108 
109 /*
110  *      Generic checksumming routines for UDP(-Lite) v4 and v6
111  */
112 static 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 
119 static 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  */
131 static 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 
141 static 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 
152 static 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 
158 void udp_set_csum(bool nocheck, struct sk_buff *skb,
159                   __be32 saddr, __be32 daddr, int len);
160 
161 static inline void udp_csum_pull_header(struct sk_buff *skb)
162 {
163         if (!skb->csum_valid && skb->ip_summed == CHECKSUM_NONE)
164                 skb->csum = csum_partial(skb->data, sizeof(struct udphdr),
165                                          skb->csum);
166         skb_pull_rcsum(skb, sizeof(struct udphdr));
167         UDP_SKB_CB(skb)->cscov -= sizeof(struct udphdr);
168 }
169 
170 typedef struct sock *(*udp_lookup_t)(struct sk_buff *skb, __be16 sport,
171                                      __be16 dport);
172 
173 struct sk_buff **udp_gro_receive(struct sk_buff **head, struct sk_buff *skb,
174                                  struct udphdr *uh, udp_lookup_t lookup);
175 int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
176 
177 static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
178 {
179         struct udphdr *uh;
180         unsigned int hlen, off;
181 
182         off  = skb_gro_offset(skb);
183         hlen = off + sizeof(*uh);
184         uh   = skb_gro_header_fast(skb, off);
185         if (skb_gro_header_hard(skb, hlen))
186                 uh = skb_gro_header_slow(skb, hlen, off);
187 
188         return uh;
189 }
190 
191 /* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
192 static inline int udp_lib_hash(struct sock *sk)
193 {
194         BUG();
195         return 0;
196 }
197 
198 void udp_lib_unhash(struct sock *sk);
199 void udp_lib_rehash(struct sock *sk, u16 new_hash);
200 
201 static inline void udp_lib_close(struct sock *sk, long timeout)
202 {
203         sk_common_release(sk);
204 }
205 
206 int udp_lib_get_port(struct sock *sk, unsigned short snum,
207                      unsigned int hash2_nulladdr);
208 
209 u32 udp_flow_hashrnd(void);
210 
211 static inline __be16 udp_flow_src_port(struct net *net, struct sk_buff *skb,
212                                        int min, int max, bool use_eth)
213 {
214         u32 hash;
215 
216         if (min >= max) {
217                 /* Use default range */
218                 inet_get_local_port_range(net, &min, &max);
219         }
220 
221         hash = skb_get_hash(skb);
222         if (unlikely(!hash)) {
223                 if (use_eth) {
224                         /* Can't find a normal hash, caller has indicated an
225                          * Ethernet packet so use that to compute a hash.
226                          */
227                         hash = jhash(skb->data, 2 * ETH_ALEN,
228                                      (__force u32) skb->protocol);
229                 } else {
230                         /* Can't derive any sort of hash for the packet, set
231                          * to some consistent random value.
232                          */
233                         hash = udp_flow_hashrnd();
234                 }
235         }
236 
237         /* Since this is being sent on the wire obfuscate hash a bit
238          * to minimize possbility that any useful information to an
239          * attacker is leaked. Only upper 16 bits are relevant in the
240          * computation for 16 bit port value.
241          */
242         hash ^= hash << 16;
243 
244         return htons((((u64) hash * (max - min)) >> 32) + min);
245 }
246 
247 /* net/ipv4/udp.c */
248 void udp_destruct_sock(struct sock *sk);
249 void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len);
250 int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb);
251 void udp_skb_destructor(struct sock *sk, struct sk_buff *skb);
252 struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
253                                int noblock, int *peeked, int *off, int *err);
254 static inline struct sk_buff *skb_recv_udp(struct sock *sk, unsigned int flags,
255                                            int noblock, int *err)
256 {
257         int peeked, off = 0;
258 
259         return __skb_recv_udp(sk, flags, noblock, &peeked, &off, err);
260 }
261 
262 int udp_v4_early_demux(struct sk_buff *skb);
263 bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst);
264 int udp_get_port(struct sock *sk, unsigned short snum,
265                  int (*saddr_cmp)(const struct sock *,
266                                   const struct sock *));
267 void udp_err(struct sk_buff *, u32);
268 int udp_abort(struct sock *sk, int err);
269 int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len);
270 int udp_push_pending_frames(struct sock *sk);
271 void udp_flush_pending_frames(struct sock *sk);
272 void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst);
273 int udp_rcv(struct sk_buff *skb);
274 int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
275 int udp_init_sock(struct sock *sk);
276 int __udp_disconnect(struct sock *sk, int flags);
277 int udp_disconnect(struct sock *sk, int flags);
278 unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait);
279 struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb,
280                                        netdev_features_t features,
281                                        bool is_ipv6);
282 int udp_lib_getsockopt(struct sock *sk, int level, int optname,
283                        char __user *optval, int __user *optlen);
284 int udp_lib_setsockopt(struct sock *sk, int level, int optname,
285                        char __user *optval, unsigned int optlen,
286                        int (*push_pending_frames)(struct sock *));
287 struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
288                              __be32 daddr, __be16 dport, int dif);
289 struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
290                                __be32 daddr, __be16 dport, int dif, int sdif,
291                                struct udp_table *tbl, struct sk_buff *skb);
292 struct sock *udp4_lib_lookup_skb(struct sk_buff *skb,
293                                  __be16 sport, __be16 dport);
294 struct sock *udp6_lib_lookup(struct net *net,
295                              const struct in6_addr *saddr, __be16 sport,
296                              const struct in6_addr *daddr, __be16 dport,
297                              int dif);
298 struct sock *__udp6_lib_lookup(struct net *net,
299                                const struct in6_addr *saddr, __be16 sport,
300                                const struct in6_addr *daddr, __be16 dport,
301                                int dif, int sdif, struct udp_table *tbl,
302                                struct sk_buff *skb);
303 struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
304                                  __be16 sport, __be16 dport);
305 
306 /* UDP uses skb->dev_scratch to cache as much information as possible and avoid
307  * possibly multiple cache miss on dequeue()
308  */
309 struct udp_dev_scratch {
310         /* skb->truesize and the stateless bit are embedded in a single field;
311          * do not use a bitfield since the compiler emits better/smaller code
312          * this way
313          */
314         u32 _tsize_state;
315 
316 #if BITS_PER_LONG == 64
317         /* len and the bit needed to compute skb_csum_unnecessary
318          * will be on cold cache lines at recvmsg time.
319          * skb->len can be stored on 16 bits since the udp header has been
320          * already validated and pulled.
321          */
322         u16 len;
323         bool is_linear;
324         bool csum_unnecessary;
325 #endif
326 };
327 
328 static inline struct udp_dev_scratch *udp_skb_scratch(struct sk_buff *skb)
329 {
330         return (struct udp_dev_scratch *)&skb->dev_scratch;
331 }
332 
333 #if BITS_PER_LONG == 64
334 static inline unsigned int udp_skb_len(struct sk_buff *skb)
335 {
336         return udp_skb_scratch(skb)->len;
337 }
338 
339 static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
340 {
341         return udp_skb_scratch(skb)->csum_unnecessary;
342 }
343 
344 static inline bool udp_skb_is_linear(struct sk_buff *skb)
345 {
346         return udp_skb_scratch(skb)->is_linear;
347 }
348 
349 #else
350 static inline unsigned int udp_skb_len(struct sk_buff *skb)
351 {
352         return skb->len;
353 }
354 
355 static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
356 {
357         return skb_csum_unnecessary(skb);
358 }
359 
360 static inline bool udp_skb_is_linear(struct sk_buff *skb)
361 {
362         return !skb_is_nonlinear(skb);
363 }
364 #endif
365 
366 static inline int copy_linear_skb(struct sk_buff *skb, int len, int off,
367                                   struct iov_iter *to)
368 {
369         int n;
370 
371         n = copy_to_iter(skb->data + off, len, to);
372         if (n == len)
373                 return 0;
374 
375         iov_iter_revert(to, n);
376         return -EFAULT;
377 }
378 
379 /*
380  *      SNMP statistics for UDP and UDP-Lite
381  */
382 #define UDP_INC_STATS(net, field, is_udplite)                 do { \
383         if (is_udplite) SNMP_INC_STATS((net)->mib.udplite_statistics, field);       \
384         else            SNMP_INC_STATS((net)->mib.udp_statistics, field);  }  while(0)
385 #define __UDP_INC_STATS(net, field, is_udplite)               do { \
386         if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_statistics, field);         \
387         else            __SNMP_INC_STATS((net)->mib.udp_statistics, field);    }  while(0)
388 
389 #define __UDP6_INC_STATS(net, field, is_udplite)            do { \
390         if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);\
391         else            __SNMP_INC_STATS((net)->mib.udp_stats_in6, field);  \
392 } while(0)
393 #define UDP6_INC_STATS(net, field, __lite)                  do { \
394         if (__lite) SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);  \
395         else        SNMP_INC_STATS((net)->mib.udp_stats_in6, field);      \
396 } while(0)
397 
398 #if IS_ENABLED(CONFIG_IPV6)
399 #define __UDPX_INC_STATS(sk, field)                                     \
400 do {                                                                    \
401         if ((sk)->sk_family == AF_INET)                                 \
402                 __UDP_INC_STATS(sock_net(sk), field, 0);                \
403         else                                                            \
404                 __UDP6_INC_STATS(sock_net(sk), field, 0);               \
405 } while (0)
406 #else
407 #define __UDPX_INC_STATS(sk, field) __UDP_INC_STATS(sock_net(sk), field, 0)
408 #endif
409 
410 /* /proc */
411 int udp_seq_open(struct inode *inode, struct file *file);
412 
413 struct udp_seq_afinfo {
414         char                            *name;
415         sa_family_t                     family;
416         struct udp_table                *udp_table;
417         const struct file_operations    *seq_fops;
418         struct seq_operations           seq_ops;
419 };
420 
421 struct udp_iter_state {
422         struct seq_net_private  p;
423         sa_family_t             family;
424         int                     bucket;
425         struct udp_table        *udp_table;
426 };
427 
428 #ifdef CONFIG_PROC_FS
429 int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo);
430 void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo);
431 
432 int udp4_proc_init(void);
433 void udp4_proc_exit(void);
434 #endif
435 
436 int udpv4_offload_init(void);
437 
438 void udp_init(void);
439 
440 void udp_encap_enable(void);
441 #if IS_ENABLED(CONFIG_IPV6)
442 void udpv6_encap_enable(void);
443 #endif
444 
445 #endif  /* _UDP_H */
446 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp