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 * The User Datagram Protocol (UDP).
8 * Version: $Id: udp.c,v 1.102 2002/02/01 22:01:04 davem Exp $
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
13 * Alan Cox, <Alan.Cox@linux.org>
14 * Hirokazu Takahashi, <taka@valinux.co.jp>
17 * Alan Cox : verify_area() calls
18 * Alan Cox : stopped close while in use off icmp
19 * messages. Not a fix but a botch that
20 * for udp at least is 'valid'.
21 * Alan Cox : Fixed icmp handling properly
22 * Alan Cox : Correct error for oversized datagrams
23 * Alan Cox : Tidied select() semantics.
24 * Alan Cox : udp_err() fixed properly, also now
25 * select and read wake correctly on errors
26 * Alan Cox : udp_send verify_area moved to avoid mem leak
27 * Alan Cox : UDP can count its memory
28 * Alan Cox : send to an unknown connection causes
29 * an ECONNREFUSED off the icmp, but
31 * Alan Cox : Switched to new sk_buff handlers. No more backlog!
32 * Alan Cox : Using generic datagram code. Even smaller and the PEEK
33 * bug no longer crashes it.
34 * Fred Van Kempen : Net2e support for sk->broadcast.
35 * Alan Cox : Uses skb_free_datagram
36 * Alan Cox : Added get/set sockopt support.
37 * Alan Cox : Broadcasting without option set returns EACCES.
38 * Alan Cox : No wakeup calls. Instead we now use the callbacks.
39 * Alan Cox : Use ip_tos and ip_ttl
40 * Alan Cox : SNMP Mibs
41 * Alan Cox : MSG_DONTROUTE, and 0.0.0.0 support.
42 * Matt Dillon : UDP length checks.
43 * Alan Cox : Smarter af_inet used properly.
44 * Alan Cox : Use new kernel side addressing.
45 * Alan Cox : Incorrect return on truncated datagram receive.
46 * Arnt Gulbrandsen : New udp_send and stuff
47 * Alan Cox : Cache last socket
48 * Alan Cox : Route cache
49 * Jon Peatfield : Minor efficiency fix to sendto().
50 * Mike Shaver : RFC1122 checks.
51 * Alan Cox : Nonblocking error fix.
52 * Willy Konynenberg : Transparent proxying support.
53 * Mike McLagan : Routing by source
54 * David S. Miller : New socket lookup architecture.
55 * Last socket cache retained as it
56 * does have a high hit rate.
57 * Olaf Kirch : Don't linearise iovec on sendmsg.
58 * Andi Kleen : Some cleanups, cache destination entry
60 * Vitaly E. Lavrov : Transparent proxy revived after year coma.
61 * Melvin Smith : Check msg_name not msg_namelen in sendto(),
62 * return ENOTCONN for unconnected sockets (POSIX)
63 * Janos Farkas : don't deliver multi/broadcasts to a different
64 * bound-to-device socket
65 * Hirokazu Takahashi : HW checksumming for outgoing UDP
67 * Hirokazu Takahashi : sendfile() on UDP works now.
68 * Arnaldo C. Melo : convert /proc/net/udp to seq_file
69 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
70 * Alexey Kuznetsov: allow both IPv4 and IPv6 sockets to bind
71 * a single port at the same time.
72 * Derek Atkins <derek@ihtfp.com>: Add Encapulation Support
73 * James Chapman : Add L2TP encapsulation type.
76 * This program is free software; you can redistribute it and/or
77 * modify it under the terms of the GNU General Public License
78 * as published by the Free Software Foundation; either version
79 * 2 of the License, or (at your option) any later version.
82 #include <asm/system.h>
83 #include <asm/uaccess.h>
84 #include <asm/ioctls.h>
85 #include <linux/bootmem.h>
86 #include <linux/types.h>
87 #include <linux/fcntl.h>
88 #include <linux/module.h>
89 #include <linux/socket.h>
90 #include <linux/sockios.h>
91 #include <linux/igmp.h>
93 #include <linux/errno.h>
94 #include <linux/timer.h>
96 #include <linux/inet.h>
97 #include <linux/netdevice.h>
98 #include <net/tcp_states.h>
99 #include <linux/skbuff.h>
100 #include <linux/proc_fs.h>
101 #include <linux/seq_file.h>
102 #include <net/net_namespace.h>
103 #include <net/icmp.h>
104 #include <net/route.h>
105 #include <net/checksum.h>
106 #include <net/xfrm.h>
107 #include "udp_impl.h"
110 * Snmp MIB for the UDP layer
113 DEFINE_SNMP_STAT(struct udp_mib
, udp_statistics
) __read_mostly
;
114 EXPORT_SYMBOL(udp_statistics
);
116 DEFINE_SNMP_STAT(struct udp_mib
, udp_stats_in6
) __read_mostly
;
117 EXPORT_SYMBOL(udp_stats_in6
);
119 struct hlist_head udp_hash
[UDP_HTABLE_SIZE
];
120 DEFINE_RWLOCK(udp_hash_lock
);
122 int sysctl_udp_mem
[3] __read_mostly
;
123 int sysctl_udp_rmem_min __read_mostly
;
124 int sysctl_udp_wmem_min __read_mostly
;
126 EXPORT_SYMBOL(sysctl_udp_mem
);
127 EXPORT_SYMBOL(sysctl_udp_rmem_min
);
128 EXPORT_SYMBOL(sysctl_udp_wmem_min
);
130 atomic_t udp_memory_allocated
;
131 EXPORT_SYMBOL(udp_memory_allocated
);
133 static inline int __udp_lib_lport_inuse(struct net
*net
, __u16 num
,
134 const struct hlist_head udptable
[])
137 struct hlist_node
*node
;
139 sk_for_each(sk
, node
, &udptable
[num
& (UDP_HTABLE_SIZE
- 1)])
140 if (net_eq(sock_net(sk
), net
) && sk
->sk_hash
== num
)
146 * udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6
148 * @sk: socket struct in question
149 * @snum: port number to look up
150 * @saddr_comp: AF-dependent comparison of bound local IP addresses
152 int udp_lib_get_port(struct sock
*sk
, unsigned short snum
,
153 int (*saddr_comp
)(const struct sock
*sk1
,
154 const struct sock
*sk2
) )
156 struct hlist_head
*udptable
= sk
->sk_prot
->h
.udp_hash
;
157 struct hlist_node
*node
;
158 struct hlist_head
*head
;
161 struct net
*net
= sock_net(sk
);
163 write_lock_bh(&udp_hash_lock
);
166 int i
, low
, high
, remaining
;
167 unsigned rover
, best
, best_size_so_far
;
169 inet_get_local_port_range(&low
, &high
);
170 remaining
= (high
- low
) + 1;
172 best_size_so_far
= UINT_MAX
;
173 best
= rover
= net_random() % remaining
+ low
;
175 /* 1st pass: look for empty (or shortest) hash chain */
176 for (i
= 0; i
< UDP_HTABLE_SIZE
; i
++) {
179 head
= &udptable
[rover
& (UDP_HTABLE_SIZE
- 1)];
180 if (hlist_empty(head
))
183 sk_for_each(sk2
, node
, head
) {
184 if (++size
>= best_size_so_far
)
187 best_size_so_far
= size
;
190 /* fold back if end of range */
192 rover
= low
+ ((rover
- low
)
193 & (UDP_HTABLE_SIZE
- 1));
198 /* 2nd pass: find hole in shortest hash chain */
200 for (i
= 0; i
< (1 << 16) / UDP_HTABLE_SIZE
; i
++) {
201 if (! __udp_lib_lport_inuse(net
, rover
, udptable
))
203 rover
+= UDP_HTABLE_SIZE
;
205 rover
= low
+ ((rover
- low
)
206 & (UDP_HTABLE_SIZE
- 1));
210 /* All ports in use! */
216 head
= &udptable
[snum
& (UDP_HTABLE_SIZE
- 1)];
218 sk_for_each(sk2
, node
, head
)
219 if (sk2
->sk_hash
== snum
&&
221 net_eq(sock_net(sk2
), net
) &&
222 (!sk2
->sk_reuse
|| !sk
->sk_reuse
) &&
223 (!sk2
->sk_bound_dev_if
|| !sk
->sk_bound_dev_if
224 || sk2
->sk_bound_dev_if
== sk
->sk_bound_dev_if
) &&
225 (*saddr_comp
)(sk
, sk2
) )
229 inet_sk(sk
)->num
= snum
;
231 if (sk_unhashed(sk
)) {
232 head
= &udptable
[snum
& (UDP_HTABLE_SIZE
- 1)];
233 sk_add_node(sk
, head
);
234 sock_prot_inuse_add(sock_net(sk
), sk
->sk_prot
, 1);
238 write_unlock_bh(&udp_hash_lock
);
242 static int ipv4_rcv_saddr_equal(const struct sock
*sk1
, const struct sock
*sk2
)
244 struct inet_sock
*inet1
= inet_sk(sk1
), *inet2
= inet_sk(sk2
);
246 return ( !ipv6_only_sock(sk2
) &&
247 (!inet1
->rcv_saddr
|| !inet2
->rcv_saddr
||
248 inet1
->rcv_saddr
== inet2
->rcv_saddr
));
251 int udp_v4_get_port(struct sock
*sk
, unsigned short snum
)
253 return udp_lib_get_port(sk
, snum
, ipv4_rcv_saddr_equal
);
256 /* UDP is nearly always wildcards out the wazoo, it makes no sense to try
257 * harder than this. -DaveM
259 static struct sock
*__udp4_lib_lookup(struct net
*net
, __be32 saddr
,
260 __be16 sport
, __be32 daddr
, __be16 dport
,
261 int dif
, struct hlist_head udptable
[])
263 struct sock
*sk
, *result
= NULL
;
264 struct hlist_node
*node
;
265 unsigned short hnum
= ntohs(dport
);
268 read_lock(&udp_hash_lock
);
269 sk_for_each(sk
, node
, &udptable
[hnum
& (UDP_HTABLE_SIZE
- 1)]) {
270 struct inet_sock
*inet
= inet_sk(sk
);
272 if (net_eq(sock_net(sk
), net
) && sk
->sk_hash
== hnum
&&
273 !ipv6_only_sock(sk
)) {
274 int score
= (sk
->sk_family
== PF_INET
? 1 : 0);
275 if (inet
->rcv_saddr
) {
276 if (inet
->rcv_saddr
!= daddr
)
281 if (inet
->daddr
!= saddr
)
286 if (inet
->dport
!= sport
)
290 if (sk
->sk_bound_dev_if
) {
291 if (sk
->sk_bound_dev_if
!= dif
)
298 } else if (score
> badness
) {
306 read_unlock(&udp_hash_lock
);
310 static inline struct sock
*udp_v4_mcast_next(struct sock
*sk
,
311 __be16 loc_port
, __be32 loc_addr
,
312 __be16 rmt_port
, __be32 rmt_addr
,
315 struct hlist_node
*node
;
317 unsigned short hnum
= ntohs(loc_port
);
319 sk_for_each_from(s
, node
) {
320 struct inet_sock
*inet
= inet_sk(s
);
322 if (s
->sk_hash
!= hnum
||
323 (inet
->daddr
&& inet
->daddr
!= rmt_addr
) ||
324 (inet
->dport
!= rmt_port
&& inet
->dport
) ||
325 (inet
->rcv_saddr
&& inet
->rcv_saddr
!= loc_addr
) ||
327 (s
->sk_bound_dev_if
&& s
->sk_bound_dev_if
!= dif
))
329 if (!ip_mc_sf_allow(s
, loc_addr
, rmt_addr
, dif
))
339 * This routine is called by the ICMP module when it gets some
340 * sort of error condition. If err < 0 then the socket should
341 * be closed and the error returned to the user. If err > 0
342 * it's just the icmp type << 8 | icmp code.
343 * Header points to the ip header of the error packet. We move
344 * on past this. Then (as it used to claim before adjustment)
345 * header points to the first 8 bytes of the udp header. We need
346 * to find the appropriate port.
349 void __udp4_lib_err(struct sk_buff
*skb
, u32 info
, struct hlist_head udptable
[])
351 struct inet_sock
*inet
;
352 struct iphdr
*iph
= (struct iphdr
*)skb
->data
;
353 struct udphdr
*uh
= (struct udphdr
*)(skb
->data
+(iph
->ihl
<<2));
354 const int type
= icmp_hdr(skb
)->type
;
355 const int code
= icmp_hdr(skb
)->code
;
360 sk
= __udp4_lib_lookup(dev_net(skb
->dev
), iph
->daddr
, uh
->dest
,
361 iph
->saddr
, uh
->source
, skb
->dev
->ifindex
, udptable
);
363 ICMP_INC_STATS_BH(ICMP_MIB_INERRORS
);
364 return; /* No socket for error */
373 case ICMP_TIME_EXCEEDED
:
376 case ICMP_SOURCE_QUENCH
:
378 case ICMP_PARAMETERPROB
:
382 case ICMP_DEST_UNREACH
:
383 if (code
== ICMP_FRAG_NEEDED
) { /* Path MTU discovery */
384 if (inet
->pmtudisc
!= IP_PMTUDISC_DONT
) {
392 if (code
<= NR_ICMP_UNREACH
) {
393 harderr
= icmp_err_convert
[code
].fatal
;
394 err
= icmp_err_convert
[code
].errno
;
400 * RFC1122: OK. Passes ICMP errors back to application, as per
403 if (!inet
->recverr
) {
404 if (!harderr
|| sk
->sk_state
!= TCP_ESTABLISHED
)
407 ip_icmp_error(sk
, skb
, err
, uh
->dest
, info
, (u8
*)(uh
+1));
410 sk
->sk_error_report(sk
);
415 void udp_err(struct sk_buff
*skb
, u32 info
)
417 __udp4_lib_err(skb
, info
, udp_hash
);
421 * Throw away all pending data and cancel the corking. Socket is locked.
423 static void udp_flush_pending_frames(struct sock
*sk
)
425 struct udp_sock
*up
= udp_sk(sk
);
430 ip_flush_pending_frames(sk
);
435 * udp4_hwcsum_outgoing - handle outgoing HW checksumming
436 * @sk: socket we are sending on
437 * @skb: sk_buff containing the filled-in UDP header
438 * (checksum field must be zeroed out)
440 static void udp4_hwcsum_outgoing(struct sock
*sk
, struct sk_buff
*skb
,
441 __be32 src
, __be32 dst
, int len
)
444 struct udphdr
*uh
= udp_hdr(skb
);
447 if (skb_queue_len(&sk
->sk_write_queue
) == 1) {
449 * Only one fragment on the socket.
451 skb
->csum_start
= skb_transport_header(skb
) - skb
->head
;
452 skb
->csum_offset
= offsetof(struct udphdr
, check
);
453 uh
->check
= ~csum_tcpudp_magic(src
, dst
, len
, IPPROTO_UDP
, 0);
456 * HW-checksum won't work as there are two or more
457 * fragments on the socket so that all csums of sk_buffs
460 offset
= skb_transport_offset(skb
);
461 skb
->csum
= skb_checksum(skb
, offset
, skb
->len
- offset
, 0);
463 skb
->ip_summed
= CHECKSUM_NONE
;
465 skb_queue_walk(&sk
->sk_write_queue
, skb
) {
466 csum
= csum_add(csum
, skb
->csum
);
469 uh
->check
= csum_tcpudp_magic(src
, dst
, len
, IPPROTO_UDP
, csum
);
471 uh
->check
= CSUM_MANGLED_0
;
476 * Push out all pending data as one UDP datagram. Socket is locked.
478 static int udp_push_pending_frames(struct sock
*sk
)
480 struct udp_sock
*up
= udp_sk(sk
);
481 struct inet_sock
*inet
= inet_sk(sk
);
482 struct flowi
*fl
= &inet
->cork
.fl
;
486 int is_udplite
= IS_UDPLITE(sk
);
489 /* Grab the skbuff where UDP header space exists. */
490 if ((skb
= skb_peek(&sk
->sk_write_queue
)) == NULL
)
494 * Create a UDP header
497 uh
->source
= fl
->fl_ip_sport
;
498 uh
->dest
= fl
->fl_ip_dport
;
499 uh
->len
= htons(up
->len
);
502 if (is_udplite
) /* UDP-Lite */
503 csum
= udplite_csum_outgoing(sk
, skb
);
505 else if (sk
->sk_no_check
== UDP_CSUM_NOXMIT
) { /* UDP csum disabled */
507 skb
->ip_summed
= CHECKSUM_NONE
;
510 } else if (skb
->ip_summed
== CHECKSUM_PARTIAL
) { /* UDP hardware csum */
512 udp4_hwcsum_outgoing(sk
, skb
, fl
->fl4_src
,fl
->fl4_dst
, up
->len
);
515 } else /* `normal' UDP */
516 csum
= udp_csum_outgoing(sk
, skb
);
518 /* add protocol-dependent pseudo-header */
519 uh
->check
= csum_tcpudp_magic(fl
->fl4_src
, fl
->fl4_dst
, up
->len
,
520 sk
->sk_protocol
, csum
);
522 uh
->check
= CSUM_MANGLED_0
;
525 err
= ip_push_pending_frames(sk
);
530 UDP_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS
, is_udplite
);
534 int udp_sendmsg(struct kiocb
*iocb
, struct sock
*sk
, struct msghdr
*msg
,
537 struct inet_sock
*inet
= inet_sk(sk
);
538 struct udp_sock
*up
= udp_sk(sk
);
540 struct ipcm_cookie ipc
;
541 struct rtable
*rt
= NULL
;
544 __be32 daddr
, faddr
, saddr
;
547 int err
, is_udplite
= IS_UDPLITE(sk
);
548 int corkreq
= up
->corkflag
|| msg
->msg_flags
&MSG_MORE
;
549 int (*getfrag
)(void *, char *, int, int, int, struct sk_buff
*);
558 if (msg
->msg_flags
&MSG_OOB
) /* Mirror BSD error message compatibility */
565 * There are pending frames.
566 * The socket lock must be held while it's corked.
569 if (likely(up
->pending
)) {
570 if (unlikely(up
->pending
!= AF_INET
)) {
578 ulen
+= sizeof(struct udphdr
);
581 * Get and verify the address.
584 struct sockaddr_in
* usin
= (struct sockaddr_in
*)msg
->msg_name
;
585 if (msg
->msg_namelen
< sizeof(*usin
))
587 if (usin
->sin_family
!= AF_INET
) {
588 if (usin
->sin_family
!= AF_UNSPEC
)
589 return -EAFNOSUPPORT
;
592 daddr
= usin
->sin_addr
.s_addr
;
593 dport
= usin
->sin_port
;
597 if (sk
->sk_state
!= TCP_ESTABLISHED
)
598 return -EDESTADDRREQ
;
601 /* Open fast path for connected socket.
602 Route will not be used, if at least one option is set.
606 ipc
.addr
= inet
->saddr
;
608 ipc
.oif
= sk
->sk_bound_dev_if
;
609 if (msg
->msg_controllen
) {
610 err
= ip_cmsg_send(sock_net(sk
), msg
, &ipc
);
621 ipc
.addr
= faddr
= daddr
;
623 if (ipc
.opt
&& ipc
.opt
->srr
) {
626 faddr
= ipc
.opt
->faddr
;
629 tos
= RT_TOS(inet
->tos
);
630 if (sock_flag(sk
, SOCK_LOCALROUTE
) ||
631 (msg
->msg_flags
& MSG_DONTROUTE
) ||
632 (ipc
.opt
&& ipc
.opt
->is_strictroute
)) {
637 if (ipv4_is_multicast(daddr
)) {
639 ipc
.oif
= inet
->mc_index
;
641 saddr
= inet
->mc_addr
;
646 rt
= (struct rtable
*)sk_dst_check(sk
, 0);
649 struct flowi fl
= { .oif
= ipc
.oif
,
654 .proto
= sk
->sk_protocol
,
656 { .sport
= inet
->sport
,
657 .dport
= dport
} } };
658 security_sk_classify_flow(sk
, &fl
);
659 err
= ip_route_output_flow(sock_net(sk
), &rt
, &fl
, sk
, 1);
661 if (err
== -ENETUNREACH
)
662 IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES
);
667 if ((rt
->rt_flags
& RTCF_BROADCAST
) &&
668 !sock_flag(sk
, SOCK_BROADCAST
))
671 sk_dst_set(sk
, dst_clone(&rt
->u
.dst
));
674 if (msg
->msg_flags
&MSG_CONFIRM
)
680 daddr
= ipc
.addr
= rt
->rt_dst
;
683 if (unlikely(up
->pending
)) {
684 /* The socket is already corked while preparing it. */
685 /* ... which is an evident application bug. --ANK */
688 LIMIT_NETDEBUG(KERN_DEBUG
"udp cork app bug 2\n");
693 * Now cork the socket to pend data.
695 inet
->cork
.fl
.fl4_dst
= daddr
;
696 inet
->cork
.fl
.fl_ip_dport
= dport
;
697 inet
->cork
.fl
.fl4_src
= saddr
;
698 inet
->cork
.fl
.fl_ip_sport
= inet
->sport
;
699 up
->pending
= AF_INET
;
703 getfrag
= is_udplite
? udplite_getfrag
: ip_generic_getfrag
;
704 err
= ip_append_data(sk
, getfrag
, msg
->msg_iov
, ulen
,
705 sizeof(struct udphdr
), &ipc
, rt
,
706 corkreq
? msg
->msg_flags
|MSG_MORE
: msg
->msg_flags
);
708 udp_flush_pending_frames(sk
);
710 err
= udp_push_pending_frames(sk
);
711 else if (unlikely(skb_queue_empty(&sk
->sk_write_queue
)))
722 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
723 * ENOBUFS might not be good (it's not tunable per se), but otherwise
724 * we don't have a good statistic (IpOutDiscards but it can be too many
725 * things). We could add another new stat but at least for now that
726 * seems like overkill.
728 if (err
== -ENOBUFS
|| test_bit(SOCK_NOSPACE
, &sk
->sk_socket
->flags
)) {
729 UDP_INC_STATS_USER(UDP_MIB_SNDBUFERRORS
, is_udplite
);
734 dst_confirm(&rt
->u
.dst
);
735 if (!(msg
->msg_flags
&MSG_PROBE
) || len
)
736 goto back_from_confirm
;
741 int udp_sendpage(struct sock
*sk
, struct page
*page
, int offset
,
742 size_t size
, int flags
)
744 struct udp_sock
*up
= udp_sk(sk
);
748 struct msghdr msg
= { .msg_flags
= flags
|MSG_MORE
};
750 /* Call udp_sendmsg to specify destination address which
751 * sendpage interface can't pass.
752 * This will succeed only when the socket is connected.
754 ret
= udp_sendmsg(NULL
, sk
, &msg
, 0);
761 if (unlikely(!up
->pending
)) {
764 LIMIT_NETDEBUG(KERN_DEBUG
"udp cork app bug 3\n");
768 ret
= ip_append_page(sk
, page
, offset
, size
, flags
);
769 if (ret
== -EOPNOTSUPP
) {
771 return sock_no_sendpage(sk
->sk_socket
, page
, offset
,
775 udp_flush_pending_frames(sk
);
780 if (!(up
->corkflag
|| (flags
&MSG_MORE
)))
781 ret
= udp_push_pending_frames(sk
);
790 * IOCTL requests applicable to the UDP protocol
793 int udp_ioctl(struct sock
*sk
, int cmd
, unsigned long arg
)
798 int amount
= atomic_read(&sk
->sk_wmem_alloc
);
799 return put_user(amount
, (int __user
*)arg
);
805 unsigned long amount
;
808 spin_lock_bh(&sk
->sk_receive_queue
.lock
);
809 skb
= skb_peek(&sk
->sk_receive_queue
);
812 * We will only return the amount
813 * of this packet since that is all
816 amount
= skb
->len
- sizeof(struct udphdr
);
818 spin_unlock_bh(&sk
->sk_receive_queue
.lock
);
819 return put_user(amount
, (int __user
*)arg
);
830 * This should be easy, if there is something there we
831 * return it, otherwise we block.
834 int udp_recvmsg(struct kiocb
*iocb
, struct sock
*sk
, struct msghdr
*msg
,
835 size_t len
, int noblock
, int flags
, int *addr_len
)
837 struct inet_sock
*inet
= inet_sk(sk
);
838 struct sockaddr_in
*sin
= (struct sockaddr_in
*)msg
->msg_name
;
840 unsigned int ulen
, copied
;
843 int is_udplite
= IS_UDPLITE(sk
);
846 * Check any passed addresses
849 *addr_len
=sizeof(*sin
);
851 if (flags
& MSG_ERRQUEUE
)
852 return ip_recv_error(sk
, msg
, len
);
855 skb
= __skb_recv_datagram(sk
, flags
| (noblock
? MSG_DONTWAIT
: 0),
860 ulen
= skb
->len
- sizeof(struct udphdr
);
864 else if (copied
< ulen
)
865 msg
->msg_flags
|= MSG_TRUNC
;
868 * If checksum is needed at all, try to do it while copying the
869 * data. If the data is truncated, or if we only want a partial
870 * coverage checksum (UDP-Lite), do it before the copy.
873 if (copied
< ulen
|| UDP_SKB_CB(skb
)->partial_cov
) {
874 if (udp_lib_checksum_complete(skb
))
878 if (skb_csum_unnecessary(skb
))
879 err
= skb_copy_datagram_iovec(skb
, sizeof(struct udphdr
),
880 msg
->msg_iov
, copied
);
882 err
= skb_copy_and_csum_datagram_iovec(skb
, sizeof(struct udphdr
), msg
->msg_iov
);
892 UDP_INC_STATS_USER(UDP_MIB_INDATAGRAMS
, is_udplite
);
894 sock_recv_timestamp(msg
, sk
, skb
);
896 /* Copy the address. */
899 sin
->sin_family
= AF_INET
;
900 sin
->sin_port
= udp_hdr(skb
)->source
;
901 sin
->sin_addr
.s_addr
= ip_hdr(skb
)->saddr
;
902 memset(sin
->sin_zero
, 0, sizeof(sin
->sin_zero
));
904 if (inet
->cmsg_flags
)
905 ip_cmsg_recv(msg
, skb
);
908 if (flags
& MSG_TRUNC
)
913 skb_free_datagram(sk
, skb
);
920 if (!skb_kill_datagram(sk
, skb
, flags
))
921 UDP_INC_STATS_USER(UDP_MIB_INERRORS
, is_udplite
);
930 int udp_disconnect(struct sock
*sk
, int flags
)
932 struct inet_sock
*inet
= inet_sk(sk
);
934 * 1003.1g - break association.
937 sk
->sk_state
= TCP_CLOSE
;
940 sk
->sk_bound_dev_if
= 0;
941 if (!(sk
->sk_userlocks
& SOCK_BINDADDR_LOCK
))
942 inet_reset_saddr(sk
);
944 if (!(sk
->sk_userlocks
& SOCK_BINDPORT_LOCK
)) {
945 sk
->sk_prot
->unhash(sk
);
955 * >0: "udp encap" protocol resubmission
957 * Note that in the success and error cases, the skb is assumed to
958 * have either been requeued or freed.
960 int udp_queue_rcv_skb(struct sock
* sk
, struct sk_buff
*skb
)
962 struct udp_sock
*up
= udp_sk(sk
);
964 int is_udplite
= IS_UDPLITE(sk
);
967 * Charge it to the socket, dropping if the queue is full.
969 if (!xfrm4_policy_check(sk
, XFRM_POLICY_IN
, skb
))
973 if (up
->encap_type
) {
975 * This is an encapsulation socket so pass the skb to
976 * the socket's udp_encap_rcv() hook. Otherwise, just
977 * fall through and pass this up the UDP socket.
978 * up->encap_rcv() returns the following value:
979 * =0 if skb was successfully passed to the encap
980 * handler or was discarded by it.
981 * >0 if skb should be passed on to UDP.
982 * <0 if skb should be resubmitted as proto -N
985 /* if we're overly short, let UDP handle it */
986 if (skb
->len
> sizeof(struct udphdr
) &&
987 up
->encap_rcv
!= NULL
) {
990 ret
= (*up
->encap_rcv
)(sk
, skb
);
992 UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS
,
998 /* FALLTHROUGH -- it's a UDP Packet */
1002 * UDP-Lite specific tests, ignored on UDP sockets
1004 if ((is_udplite
& UDPLITE_RECV_CC
) && UDP_SKB_CB(skb
)->partial_cov
) {
1007 * MIB statistics other than incrementing the error count are
1008 * disabled for the following two types of errors: these depend
1009 * on the application settings, not on the functioning of the
1010 * protocol stack as such.
1012 * RFC 3828 here recommends (sec 3.3): "There should also be a
1013 * way ... to ... at least let the receiving application block
1014 * delivery of packets with coverage values less than a value
1015 * provided by the application."
1017 if (up
->pcrlen
== 0) { /* full coverage was set */
1018 LIMIT_NETDEBUG(KERN_WARNING
"UDPLITE: partial coverage "
1019 "%d while full coverage %d requested\n",
1020 UDP_SKB_CB(skb
)->cscov
, skb
->len
);
1023 /* The next case involves violating the min. coverage requested
1024 * by the receiver. This is subtle: if receiver wants x and x is
1025 * greater than the buffersize/MTU then receiver will complain
1026 * that it wants x while sender emits packets of smaller size y.
1027 * Therefore the above ...()->partial_cov statement is essential.
1029 if (UDP_SKB_CB(skb
)->cscov
< up
->pcrlen
) {
1030 LIMIT_NETDEBUG(KERN_WARNING
1031 "UDPLITE: coverage %d too small, need min %d\n",
1032 UDP_SKB_CB(skb
)->cscov
, up
->pcrlen
);
1037 if (sk
->sk_filter
) {
1038 if (udp_lib_checksum_complete(skb
))
1042 if ((rc
= sock_queue_rcv_skb(sk
,skb
)) < 0) {
1043 /* Note that an ENOMEM error is charged twice */
1045 UDP_INC_STATS_BH(UDP_MIB_RCVBUFERRORS
, is_udplite
);
1052 UDP_INC_STATS_BH(UDP_MIB_INERRORS
, is_udplite
);
1058 * Multicasts and broadcasts go to each listener.
1060 * Note: called only from the BH handler context,
1061 * so we don't need to lock the hashes.
1063 static int __udp4_lib_mcast_deliver(struct sk_buff
*skb
,
1065 __be32 saddr
, __be32 daddr
,
1066 struct hlist_head udptable
[])
1071 read_lock(&udp_hash_lock
);
1072 sk
= sk_head(&udptable
[ntohs(uh
->dest
) & (UDP_HTABLE_SIZE
- 1)]);
1073 dif
= skb
->dev
->ifindex
;
1074 sk
= udp_v4_mcast_next(sk
, uh
->dest
, daddr
, uh
->source
, saddr
, dif
);
1076 struct sock
*sknext
= NULL
;
1079 struct sk_buff
*skb1
= skb
;
1081 sknext
= udp_v4_mcast_next(sk_next(sk
), uh
->dest
, daddr
,
1082 uh
->source
, saddr
, dif
);
1084 skb1
= skb_clone(skb
, GFP_ATOMIC
);
1089 bh_lock_sock_nested(sk
);
1090 if (!sock_owned_by_user(sk
))
1091 ret
= udp_queue_rcv_skb(sk
, skb1
);
1093 sk_add_backlog(sk
, skb1
);
1097 /* we should probably re-process instead
1098 * of dropping packets here. */
1105 read_unlock(&udp_hash_lock
);
1109 /* Initialize UDP checksum. If exited with zero value (success),
1110 * CHECKSUM_UNNECESSARY means, that no more checks are required.
1111 * Otherwise, csum completion requires chacksumming packet body,
1112 * including udp header and folding it to skb->csum.
1114 static inline int udp4_csum_init(struct sk_buff
*skb
, struct udphdr
*uh
,
1117 const struct iphdr
*iph
;
1120 UDP_SKB_CB(skb
)->partial_cov
= 0;
1121 UDP_SKB_CB(skb
)->cscov
= skb
->len
;
1123 if (proto
== IPPROTO_UDPLITE
) {
1124 err
= udplite_checksum_init(skb
, uh
);
1130 if (uh
->check
== 0) {
1131 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
1132 } else if (skb
->ip_summed
== CHECKSUM_COMPLETE
) {
1133 if (!csum_tcpudp_magic(iph
->saddr
, iph
->daddr
, skb
->len
,
1135 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
1137 if (!skb_csum_unnecessary(skb
))
1138 skb
->csum
= csum_tcpudp_nofold(iph
->saddr
, iph
->daddr
,
1139 skb
->len
, proto
, 0);
1140 /* Probably, we should checksum udp header (it should be in cache
1141 * in any case) and data in tiny packets (< rx copybreak).
1148 * All we need to do is get the socket, and then do a checksum.
1151 int __udp4_lib_rcv(struct sk_buff
*skb
, struct hlist_head udptable
[],
1155 struct udphdr
*uh
= udp_hdr(skb
);
1156 unsigned short ulen
;
1157 struct rtable
*rt
= (struct rtable
*)skb
->dst
;
1158 __be32 saddr
= ip_hdr(skb
)->saddr
;
1159 __be32 daddr
= ip_hdr(skb
)->daddr
;
1162 * Validate the packet.
1164 if (!pskb_may_pull(skb
, sizeof(struct udphdr
)))
1165 goto drop
; /* No space for header. */
1167 ulen
= ntohs(uh
->len
);
1168 if (ulen
> skb
->len
)
1171 if (proto
== IPPROTO_UDP
) {
1172 /* UDP validates ulen. */
1173 if (ulen
< sizeof(*uh
) || pskb_trim_rcsum(skb
, ulen
))
1178 if (udp4_csum_init(skb
, uh
, proto
))
1181 if (rt
->rt_flags
& (RTCF_BROADCAST
|RTCF_MULTICAST
))
1182 return __udp4_lib_mcast_deliver(skb
, uh
, saddr
, daddr
, udptable
);
1184 sk
= __udp4_lib_lookup(dev_net(skb
->dev
), saddr
, uh
->source
, daddr
,
1185 uh
->dest
, inet_iif(skb
), udptable
);
1189 bh_lock_sock_nested(sk
);
1190 if (!sock_owned_by_user(sk
))
1191 ret
= udp_queue_rcv_skb(sk
, skb
);
1193 sk_add_backlog(sk
, skb
);
1197 /* a return value > 0 means to resubmit the input, but
1198 * it wants the return to be -protocol, or 0
1205 if (!xfrm4_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
1209 /* No socket. Drop packet silently, if checksum is wrong */
1210 if (udp_lib_checksum_complete(skb
))
1213 UDP_INC_STATS_BH(UDP_MIB_NOPORTS
, proto
== IPPROTO_UDPLITE
);
1214 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_PORT_UNREACH
, 0);
1217 * Hmm. We got an UDP packet to a port to which we
1218 * don't wanna listen. Ignore it.
1224 LIMIT_NETDEBUG(KERN_DEBUG
"UDP%s: short packet: From " NIPQUAD_FMT
":%u %d/%d to " NIPQUAD_FMT
":%u\n",
1225 proto
== IPPROTO_UDPLITE
? "-Lite" : "",
1236 * RFC1122: OK. Discards the bad packet silently (as far as
1237 * the network is concerned, anyway) as per 4.1.3.4 (MUST).
1239 LIMIT_NETDEBUG(KERN_DEBUG
"UDP%s: bad checksum. From " NIPQUAD_FMT
":%u to " NIPQUAD_FMT
":%u ulen %d\n",
1240 proto
== IPPROTO_UDPLITE
? "-Lite" : "",
1247 UDP_INC_STATS_BH(UDP_MIB_INERRORS
, proto
== IPPROTO_UDPLITE
);
1252 int udp_rcv(struct sk_buff
*skb
)
1254 return __udp4_lib_rcv(skb
, udp_hash
, IPPROTO_UDP
);
1257 int udp_destroy_sock(struct sock
*sk
)
1260 udp_flush_pending_frames(sk
);
1266 * Socket option code for UDP
1268 int udp_lib_setsockopt(struct sock
*sk
, int level
, int optname
,
1269 char __user
*optval
, int optlen
,
1270 int (*push_pending_frames
)(struct sock
*))
1272 struct udp_sock
*up
= udp_sk(sk
);
1275 int is_udplite
= IS_UDPLITE(sk
);
1277 if (optlen
<sizeof(int))
1280 if (get_user(val
, (int __user
*)optval
))
1290 (*push_pending_frames
)(sk
);
1298 case UDP_ENCAP_ESPINUDP
:
1299 case UDP_ENCAP_ESPINUDP_NON_IKE
:
1300 up
->encap_rcv
= xfrm4_udp_encap_rcv
;
1302 case UDP_ENCAP_L2TPINUDP
:
1303 up
->encap_type
= val
;
1312 * UDP-Lite's partial checksum coverage (RFC 3828).
1314 /* The sender sets actual checksum coverage length via this option.
1315 * The case coverage > packet length is handled by send module. */
1316 case UDPLITE_SEND_CSCOV
:
1317 if (!is_udplite
) /* Disable the option on UDP sockets */
1318 return -ENOPROTOOPT
;
1319 if (val
!= 0 && val
< 8) /* Illegal coverage: use default (8) */
1322 up
->pcflag
|= UDPLITE_SEND_CC
;
1325 /* The receiver specifies a minimum checksum coverage value. To make
1326 * sense, this should be set to at least 8 (as done below). If zero is
1327 * used, this again means full checksum coverage. */
1328 case UDPLITE_RECV_CSCOV
:
1329 if (!is_udplite
) /* Disable the option on UDP sockets */
1330 return -ENOPROTOOPT
;
1331 if (val
!= 0 && val
< 8) /* Avoid silly minimal values. */
1334 up
->pcflag
|= UDPLITE_RECV_CC
;
1345 int udp_setsockopt(struct sock
*sk
, int level
, int optname
,
1346 char __user
*optval
, int optlen
)
1348 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
1349 return udp_lib_setsockopt(sk
, level
, optname
, optval
, optlen
,
1350 udp_push_pending_frames
);
1351 return ip_setsockopt(sk
, level
, optname
, optval
, optlen
);
1354 #ifdef CONFIG_COMPAT
1355 int compat_udp_setsockopt(struct sock
*sk
, int level
, int optname
,
1356 char __user
*optval
, int optlen
)
1358 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
1359 return udp_lib_setsockopt(sk
, level
, optname
, optval
, optlen
,
1360 udp_push_pending_frames
);
1361 return compat_ip_setsockopt(sk
, level
, optname
, optval
, optlen
);
1365 int udp_lib_getsockopt(struct sock
*sk
, int level
, int optname
,
1366 char __user
*optval
, int __user
*optlen
)
1368 struct udp_sock
*up
= udp_sk(sk
);
1371 if (get_user(len
,optlen
))
1374 len
= min_t(unsigned int, len
, sizeof(int));
1385 val
= up
->encap_type
;
1388 /* The following two cannot be changed on UDP sockets, the return is
1389 * always 0 (which corresponds to the full checksum coverage of UDP). */
1390 case UDPLITE_SEND_CSCOV
:
1394 case UDPLITE_RECV_CSCOV
:
1399 return -ENOPROTOOPT
;
1402 if (put_user(len
, optlen
))
1404 if (copy_to_user(optval
, &val
,len
))
1409 int udp_getsockopt(struct sock
*sk
, int level
, int optname
,
1410 char __user
*optval
, int __user
*optlen
)
1412 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
1413 return udp_lib_getsockopt(sk
, level
, optname
, optval
, optlen
);
1414 return ip_getsockopt(sk
, level
, optname
, optval
, optlen
);
1417 #ifdef CONFIG_COMPAT
1418 int compat_udp_getsockopt(struct sock
*sk
, int level
, int optname
,
1419 char __user
*optval
, int __user
*optlen
)
1421 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
1422 return udp_lib_getsockopt(sk
, level
, optname
, optval
, optlen
);
1423 return compat_ip_getsockopt(sk
, level
, optname
, optval
, optlen
);
1427 * udp_poll - wait for a UDP event.
1428 * @file - file struct
1430 * @wait - poll table
1432 * This is same as datagram poll, except for the special case of
1433 * blocking sockets. If application is using a blocking fd
1434 * and a packet with checksum error is in the queue;
1435 * then it could get return from select indicating data available
1436 * but then block when reading it. Add special case code
1437 * to work around these arguably broken applications.
1439 unsigned int udp_poll(struct file
*file
, struct socket
*sock
, poll_table
*wait
)
1441 unsigned int mask
= datagram_poll(file
, sock
, wait
);
1442 struct sock
*sk
= sock
->sk
;
1443 int is_lite
= IS_UDPLITE(sk
);
1445 /* Check for false positives due to checksum errors */
1446 if ( (mask
& POLLRDNORM
) &&
1447 !(file
->f_flags
& O_NONBLOCK
) &&
1448 !(sk
->sk_shutdown
& RCV_SHUTDOWN
)){
1449 struct sk_buff_head
*rcvq
= &sk
->sk_receive_queue
;
1450 struct sk_buff
*skb
;
1452 spin_lock_bh(&rcvq
->lock
);
1453 while ((skb
= skb_peek(rcvq
)) != NULL
&&
1454 udp_lib_checksum_complete(skb
)) {
1455 UDP_INC_STATS_BH(UDP_MIB_INERRORS
, is_lite
);
1456 __skb_unlink(skb
, rcvq
);
1459 spin_unlock_bh(&rcvq
->lock
);
1461 /* nothing to see, move along */
1463 mask
&= ~(POLLIN
| POLLRDNORM
);
1470 struct proto udp_prot
= {
1472 .owner
= THIS_MODULE
,
1473 .close
= udp_lib_close
,
1474 .connect
= ip4_datagram_connect
,
1475 .disconnect
= udp_disconnect
,
1477 .destroy
= udp_destroy_sock
,
1478 .setsockopt
= udp_setsockopt
,
1479 .getsockopt
= udp_getsockopt
,
1480 .sendmsg
= udp_sendmsg
,
1481 .recvmsg
= udp_recvmsg
,
1482 .sendpage
= udp_sendpage
,
1483 .backlog_rcv
= udp_queue_rcv_skb
,
1484 .hash
= udp_lib_hash
,
1485 .unhash
= udp_lib_unhash
,
1486 .get_port
= udp_v4_get_port
,
1487 .memory_allocated
= &udp_memory_allocated
,
1488 .sysctl_mem
= sysctl_udp_mem
,
1489 .sysctl_wmem
= &sysctl_udp_wmem_min
,
1490 .sysctl_rmem
= &sysctl_udp_rmem_min
,
1491 .obj_size
= sizeof(struct udp_sock
),
1492 .h
.udp_hash
= udp_hash
,
1493 #ifdef CONFIG_COMPAT
1494 .compat_setsockopt
= compat_udp_setsockopt
,
1495 .compat_getsockopt
= compat_udp_getsockopt
,
1499 /* ------------------------------------------------------------------------ */
1500 #ifdef CONFIG_PROC_FS
1502 static struct sock
*udp_get_first(struct seq_file
*seq
)
1505 struct udp_iter_state
*state
= seq
->private;
1506 struct net
*net
= seq_file_net(seq
);
1508 for (state
->bucket
= 0; state
->bucket
< UDP_HTABLE_SIZE
; ++state
->bucket
) {
1509 struct hlist_node
*node
;
1510 sk_for_each(sk
, node
, state
->hashtable
+ state
->bucket
) {
1511 if (!net_eq(sock_net(sk
), net
))
1513 if (sk
->sk_family
== state
->family
)
1522 static struct sock
*udp_get_next(struct seq_file
*seq
, struct sock
*sk
)
1524 struct udp_iter_state
*state
= seq
->private;
1525 struct net
*net
= seq_file_net(seq
);
1531 } while (sk
&& (!net_eq(sock_net(sk
), net
) || sk
->sk_family
!= state
->family
));
1533 if (!sk
&& ++state
->bucket
< UDP_HTABLE_SIZE
) {
1534 sk
= sk_head(state
->hashtable
+ state
->bucket
);
1540 static struct sock
*udp_get_idx(struct seq_file
*seq
, loff_t pos
)
1542 struct sock
*sk
= udp_get_first(seq
);
1545 while (pos
&& (sk
= udp_get_next(seq
, sk
)) != NULL
)
1547 return pos
? NULL
: sk
;
1550 static void *udp_seq_start(struct seq_file
*seq
, loff_t
*pos
)
1551 __acquires(udp_hash_lock
)
1553 read_lock(&udp_hash_lock
);
1554 return *pos
? udp_get_idx(seq
, *pos
-1) : SEQ_START_TOKEN
;
1557 static void *udp_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
1561 if (v
== SEQ_START_TOKEN
)
1562 sk
= udp_get_idx(seq
, 0);
1564 sk
= udp_get_next(seq
, v
);
1570 static void udp_seq_stop(struct seq_file
*seq
, void *v
)
1571 __releases(udp_hash_lock
)
1573 read_unlock(&udp_hash_lock
);
1576 static int udp_seq_open(struct inode
*inode
, struct file
*file
)
1578 struct udp_seq_afinfo
*afinfo
= PDE(inode
)->data
;
1579 struct udp_iter_state
*s
;
1582 err
= seq_open_net(inode
, file
, &afinfo
->seq_ops
,
1583 sizeof(struct udp_iter_state
));
1587 s
= ((struct seq_file
*)file
->private_data
)->private;
1588 s
->family
= afinfo
->family
;
1589 s
->hashtable
= afinfo
->hashtable
;
1593 /* ------------------------------------------------------------------------ */
1594 int udp_proc_register(struct net
*net
, struct udp_seq_afinfo
*afinfo
)
1596 struct proc_dir_entry
*p
;
1599 afinfo
->seq_fops
.open
= udp_seq_open
;
1600 afinfo
->seq_fops
.read
= seq_read
;
1601 afinfo
->seq_fops
.llseek
= seq_lseek
;
1602 afinfo
->seq_fops
.release
= seq_release_net
;
1604 afinfo
->seq_ops
.start
= udp_seq_start
;
1605 afinfo
->seq_ops
.next
= udp_seq_next
;
1606 afinfo
->seq_ops
.stop
= udp_seq_stop
;
1608 p
= proc_create_data(afinfo
->name
, S_IRUGO
, net
->proc_net
,
1609 &afinfo
->seq_fops
, afinfo
);
1615 void udp_proc_unregister(struct net
*net
, struct udp_seq_afinfo
*afinfo
)
1617 proc_net_remove(net
, afinfo
->name
);
1620 /* ------------------------------------------------------------------------ */
1621 static void udp4_format_sock(struct sock
*sp
, struct seq_file
*f
,
1622 int bucket
, int *len
)
1624 struct inet_sock
*inet
= inet_sk(sp
);
1625 __be32 dest
= inet
->daddr
;
1626 __be32 src
= inet
->rcv_saddr
;
1627 __u16 destp
= ntohs(inet
->dport
);
1628 __u16 srcp
= ntohs(inet
->sport
);
1630 seq_printf(f
, "%4d: %08X:%04X %08X:%04X"
1631 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p%n",
1632 bucket
, src
, srcp
, dest
, destp
, sp
->sk_state
,
1633 atomic_read(&sp
->sk_wmem_alloc
),
1634 atomic_read(&sp
->sk_rmem_alloc
),
1635 0, 0L, 0, sock_i_uid(sp
), 0, sock_i_ino(sp
),
1636 atomic_read(&sp
->sk_refcnt
), sp
, len
);
1639 int udp4_seq_show(struct seq_file
*seq
, void *v
)
1641 if (v
== SEQ_START_TOKEN
)
1642 seq_printf(seq
, "%-127s\n",
1643 " sl local_address rem_address st tx_queue "
1644 "rx_queue tr tm->when retrnsmt uid timeout "
1647 struct udp_iter_state
*state
= seq
->private;
1650 udp4_format_sock(v
, seq
, state
->bucket
, &len
);
1651 seq_printf(seq
, "%*s\n", 127 - len
,"");
1656 /* ------------------------------------------------------------------------ */
1657 static struct udp_seq_afinfo udp4_seq_afinfo
= {
1660 .hashtable
= udp_hash
,
1662 .owner
= THIS_MODULE
,
1665 .show
= udp4_seq_show
,
1669 static int udp4_proc_init_net(struct net
*net
)
1671 return udp_proc_register(net
, &udp4_seq_afinfo
);
1674 static void udp4_proc_exit_net(struct net
*net
)
1676 udp_proc_unregister(net
, &udp4_seq_afinfo
);
1679 static struct pernet_operations udp4_net_ops
= {
1680 .init
= udp4_proc_init_net
,
1681 .exit
= udp4_proc_exit_net
,
1684 int __init
udp4_proc_init(void)
1686 return register_pernet_subsys(&udp4_net_ops
);
1689 void udp4_proc_exit(void)
1691 unregister_pernet_subsys(&udp4_net_ops
);
1693 #endif /* CONFIG_PROC_FS */
1695 void __init
udp_init(void)
1697 unsigned long limit
;
1699 /* Set the pressure threshold up by the same strategy of TCP. It is a
1700 * fraction of global memory that is up to 1/2 at 256 MB, decreasing
1701 * toward zero with the amount of memory, with a floor of 128 pages.
1703 limit
= min(nr_all_pages
, 1UL<<(28-PAGE_SHIFT
)) >> (20-PAGE_SHIFT
);
1704 limit
= (limit
* (nr_all_pages
>> (20-PAGE_SHIFT
))) >> (PAGE_SHIFT
-11);
1705 limit
= max(limit
, 128UL);
1706 sysctl_udp_mem
[0] = limit
/ 4 * 3;
1707 sysctl_udp_mem
[1] = limit
;
1708 sysctl_udp_mem
[2] = sysctl_udp_mem
[0] * 2;
1710 sysctl_udp_rmem_min
= SK_MEM_QUANTUM
;
1711 sysctl_udp_wmem_min
= SK_MEM_QUANTUM
;
1714 EXPORT_SYMBOL(udp_disconnect
);
1715 EXPORT_SYMBOL(udp_hash
);
1716 EXPORT_SYMBOL(udp_hash_lock
);
1717 EXPORT_SYMBOL(udp_ioctl
);
1718 EXPORT_SYMBOL(udp_prot
);
1719 EXPORT_SYMBOL(udp_sendmsg
);
1720 EXPORT_SYMBOL(udp_lib_getsockopt
);
1721 EXPORT_SYMBOL(udp_lib_setsockopt
);
1722 EXPORT_SYMBOL(udp_poll
);
1723 EXPORT_SYMBOL(udp_lib_get_port
);
1725 #ifdef CONFIG_PROC_FS
1726 EXPORT_SYMBOL(udp_proc_register
);
1727 EXPORT_SYMBOL(udp_proc_unregister
);