1764 lines
43 KiB
C
1764 lines
43 KiB
C
/*
|
|
* 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.
|
|
*
|
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* The User Datagram Protocol (UDP).
|
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*
|
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* Version: $Id: udp.c,v 1.102 2002/02/01 22:01:04 davem Exp $
|
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*
|
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* Authors: Ross Biro
|
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* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
|
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* Arnt Gulbrandsen, <agulbra@nvg.unit.no>
|
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* Alan Cox, <Alan.Cox@linux.org>
|
|
* Hirokazu Takahashi, <taka@valinux.co.jp>
|
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*
|
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* Fixes:
|
|
* Alan Cox : verify_area() calls
|
|
* Alan Cox : stopped close while in use off icmp
|
|
* messages. Not a fix but a botch that
|
|
* for udp at least is 'valid'.
|
|
* Alan Cox : Fixed icmp handling properly
|
|
* Alan Cox : Correct error for oversized datagrams
|
|
* Alan Cox : Tidied select() semantics.
|
|
* Alan Cox : udp_err() fixed properly, also now
|
|
* select and read wake correctly on errors
|
|
* Alan Cox : udp_send verify_area moved to avoid mem leak
|
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* Alan Cox : UDP can count its memory
|
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* Alan Cox : send to an unknown connection causes
|
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* an ECONNREFUSED off the icmp, but
|
|
* does NOT close.
|
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* Alan Cox : Switched to new sk_buff handlers. No more backlog!
|
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* Alan Cox : Using generic datagram code. Even smaller and the PEEK
|
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* bug no longer crashes it.
|
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* Fred Van Kempen : Net2e support for sk->broadcast.
|
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* Alan Cox : Uses skb_free_datagram
|
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* Alan Cox : Added get/set sockopt support.
|
|
* Alan Cox : Broadcasting without option set returns EACCES.
|
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* Alan Cox : No wakeup calls. Instead we now use the callbacks.
|
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* Alan Cox : Use ip_tos and ip_ttl
|
|
* Alan Cox : SNMP Mibs
|
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* Alan Cox : MSG_DONTROUTE, and 0.0.0.0 support.
|
|
* Matt Dillon : UDP length checks.
|
|
* Alan Cox : Smarter af_inet used properly.
|
|
* Alan Cox : Use new kernel side addressing.
|
|
* Alan Cox : Incorrect return on truncated datagram receive.
|
|
* Arnt Gulbrandsen : New udp_send and stuff
|
|
* Alan Cox : Cache last socket
|
|
* Alan Cox : Route cache
|
|
* Jon Peatfield : Minor efficiency fix to sendto().
|
|
* Mike Shaver : RFC1122 checks.
|
|
* Alan Cox : Nonblocking error fix.
|
|
* Willy Konynenberg : Transparent proxying support.
|
|
* Mike McLagan : Routing by source
|
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* David S. Miller : New socket lookup architecture.
|
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* Last socket cache retained as it
|
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* does have a high hit rate.
|
|
* Olaf Kirch : Don't linearise iovec on sendmsg.
|
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* Andi Kleen : Some cleanups, cache destination entry
|
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* for connect.
|
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* Vitaly E. Lavrov : Transparent proxy revived after year coma.
|
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* Melvin Smith : Check msg_name not msg_namelen in sendto(),
|
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* return ENOTCONN for unconnected sockets (POSIX)
|
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* Janos Farkas : don't deliver multi/broadcasts to a different
|
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* bound-to-device socket
|
|
* Hirokazu Takahashi : HW checksumming for outgoing UDP
|
|
* datagrams.
|
|
* Hirokazu Takahashi : sendfile() on UDP works now.
|
|
* Arnaldo C. Melo : convert /proc/net/udp to seq_file
|
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* YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
|
|
* Alexey Kuznetsov: allow both IPv4 and IPv6 sockets to bind
|
|
* a single port at the same time.
|
|
* Derek Atkins <derek@ihtfp.com>: Add Encapulation Support
|
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* James Chapman : Add L2TP encapsulation type.
|
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*
|
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*
|
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* This program is free software; you can redistribute it and/or
|
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* modify it under the terms of the GNU General Public License
|
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* as published by the Free Software Foundation; either version
|
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* 2 of the License, or (at your option) any later version.
|
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*/
|
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|
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#include <asm/system.h>
|
|
#include <asm/uaccess.h>
|
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#include <asm/ioctls.h>
|
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#include <linux/bootmem.h>
|
|
#include <linux/types.h>
|
|
#include <linux/fcntl.h>
|
|
#include <linux/module.h>
|
|
#include <linux/socket.h>
|
|
#include <linux/sockios.h>
|
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#include <linux/igmp.h>
|
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#include <linux/in.h>
|
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#include <linux/errno.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/mm.h>
|
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#include <linux/inet.h>
|
|
#include <linux/netdevice.h>
|
|
#include <net/tcp_states.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/proc_fs.h>
|
|
#include <linux/seq_file.h>
|
|
#include <net/net_namespace.h>
|
|
#include <net/icmp.h>
|
|
#include <net/route.h>
|
|
#include <net/checksum.h>
|
|
#include <net/xfrm.h>
|
|
#include "udp_impl.h"
|
|
|
|
/*
|
|
* Snmp MIB for the UDP layer
|
|
*/
|
|
|
|
DEFINE_SNMP_STAT(struct udp_mib, udp_statistics) __read_mostly;
|
|
EXPORT_SYMBOL(udp_statistics);
|
|
|
|
DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6) __read_mostly;
|
|
EXPORT_SYMBOL(udp_stats_in6);
|
|
|
|
struct hlist_head udp_hash[UDP_HTABLE_SIZE];
|
|
DEFINE_RWLOCK(udp_hash_lock);
|
|
|
|
int sysctl_udp_mem[3] __read_mostly;
|
|
int sysctl_udp_rmem_min __read_mostly;
|
|
int sysctl_udp_wmem_min __read_mostly;
|
|
|
|
EXPORT_SYMBOL(sysctl_udp_mem);
|
|
EXPORT_SYMBOL(sysctl_udp_rmem_min);
|
|
EXPORT_SYMBOL(sysctl_udp_wmem_min);
|
|
|
|
atomic_t udp_memory_allocated;
|
|
EXPORT_SYMBOL(udp_memory_allocated);
|
|
|
|
static inline int __udp_lib_lport_inuse(struct net *net, __u16 num,
|
|
const struct hlist_head udptable[])
|
|
{
|
|
struct sock *sk;
|
|
struct hlist_node *node;
|
|
|
|
sk_for_each(sk, node, &udptable[num & (UDP_HTABLE_SIZE - 1)])
|
|
if (sk->sk_net == net && sk->sk_hash == num)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6
|
|
*
|
|
* @sk: socket struct in question
|
|
* @snum: port number to look up
|
|
* @saddr_comp: AF-dependent comparison of bound local IP addresses
|
|
*/
|
|
int udp_lib_get_port(struct sock *sk, unsigned short snum,
|
|
int (*saddr_comp)(const struct sock *sk1,
|
|
const struct sock *sk2 ) )
|
|
{
|
|
struct hlist_head *udptable = sk->sk_prot->h.udp_hash;
|
|
struct hlist_node *node;
|
|
struct hlist_head *head;
|
|
struct sock *sk2;
|
|
int error = 1;
|
|
struct net *net = sk->sk_net;
|
|
|
|
write_lock_bh(&udp_hash_lock);
|
|
|
|
if (!snum) {
|
|
int i, low, high, remaining;
|
|
unsigned rover, best, best_size_so_far;
|
|
|
|
inet_get_local_port_range(&low, &high);
|
|
remaining = (high - low) + 1;
|
|
|
|
best_size_so_far = UINT_MAX;
|
|
best = rover = net_random() % remaining + low;
|
|
|
|
/* 1st pass: look for empty (or shortest) hash chain */
|
|
for (i = 0; i < UDP_HTABLE_SIZE; i++) {
|
|
int size = 0;
|
|
|
|
head = &udptable[rover & (UDP_HTABLE_SIZE - 1)];
|
|
if (hlist_empty(head))
|
|
goto gotit;
|
|
|
|
sk_for_each(sk2, node, head) {
|
|
if (++size >= best_size_so_far)
|
|
goto next;
|
|
}
|
|
best_size_so_far = size;
|
|
best = rover;
|
|
next:
|
|
/* fold back if end of range */
|
|
if (++rover > high)
|
|
rover = low + ((rover - low)
|
|
& (UDP_HTABLE_SIZE - 1));
|
|
|
|
|
|
}
|
|
|
|
/* 2nd pass: find hole in shortest hash chain */
|
|
rover = best;
|
|
for (i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; i++) {
|
|
if (! __udp_lib_lport_inuse(net, rover, udptable))
|
|
goto gotit;
|
|
rover += UDP_HTABLE_SIZE;
|
|
if (rover > high)
|
|
rover = low + ((rover - low)
|
|
& (UDP_HTABLE_SIZE - 1));
|
|
}
|
|
|
|
|
|
/* All ports in use! */
|
|
goto fail;
|
|
|
|
gotit:
|
|
snum = rover;
|
|
} else {
|
|
head = &udptable[snum & (UDP_HTABLE_SIZE - 1)];
|
|
|
|
sk_for_each(sk2, node, head)
|
|
if (sk2->sk_hash == snum &&
|
|
sk2 != sk &&
|
|
sk2->sk_net == net &&
|
|
(!sk2->sk_reuse || !sk->sk_reuse) &&
|
|
(!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if
|
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|| sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
|
|
(*saddr_comp)(sk, sk2) )
|
|
goto fail;
|
|
}
|
|
|
|
inet_sk(sk)->num = snum;
|
|
sk->sk_hash = snum;
|
|
if (sk_unhashed(sk)) {
|
|
head = &udptable[snum & (UDP_HTABLE_SIZE - 1)];
|
|
sk_add_node(sk, head);
|
|
sock_prot_inuse_add(sk->sk_prot, 1);
|
|
}
|
|
error = 0;
|
|
fail:
|
|
write_unlock_bh(&udp_hash_lock);
|
|
return error;
|
|
}
|
|
|
|
static int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2)
|
|
{
|
|
struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2);
|
|
|
|
return ( !ipv6_only_sock(sk2) &&
|
|
(!inet1->rcv_saddr || !inet2->rcv_saddr ||
|
|
inet1->rcv_saddr == inet2->rcv_saddr ));
|
|
}
|
|
|
|
int udp_v4_get_port(struct sock *sk, unsigned short snum)
|
|
{
|
|
return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal);
|
|
}
|
|
|
|
/* UDP is nearly always wildcards out the wazoo, it makes no sense to try
|
|
* harder than this. -DaveM
|
|
*/
|
|
static struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
|
|
__be16 sport, __be32 daddr, __be16 dport,
|
|
int dif, struct hlist_head udptable[])
|
|
{
|
|
struct sock *sk, *result = NULL;
|
|
struct hlist_node *node;
|
|
unsigned short hnum = ntohs(dport);
|
|
int badness = -1;
|
|
|
|
read_lock(&udp_hash_lock);
|
|
sk_for_each(sk, node, &udptable[hnum & (UDP_HTABLE_SIZE - 1)]) {
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
|
|
if (sk->sk_net == net && sk->sk_hash == hnum &&
|
|
!ipv6_only_sock(sk)) {
|
|
int score = (sk->sk_family == PF_INET ? 1 : 0);
|
|
if (inet->rcv_saddr) {
|
|
if (inet->rcv_saddr != daddr)
|
|
continue;
|
|
score+=2;
|
|
}
|
|
if (inet->daddr) {
|
|
if (inet->daddr != saddr)
|
|
continue;
|
|
score+=2;
|
|
}
|
|
if (inet->dport) {
|
|
if (inet->dport != sport)
|
|
continue;
|
|
score+=2;
|
|
}
|
|
if (sk->sk_bound_dev_if) {
|
|
if (sk->sk_bound_dev_if != dif)
|
|
continue;
|
|
score+=2;
|
|
}
|
|
if (score == 9) {
|
|
result = sk;
|
|
break;
|
|
} else if (score > badness) {
|
|
result = sk;
|
|
badness = score;
|
|
}
|
|
}
|
|
}
|
|
if (result)
|
|
sock_hold(result);
|
|
read_unlock(&udp_hash_lock);
|
|
return result;
|
|
}
|
|
|
|
static inline struct sock *udp_v4_mcast_next(struct sock *sk,
|
|
__be16 loc_port, __be32 loc_addr,
|
|
__be16 rmt_port, __be32 rmt_addr,
|
|
int dif)
|
|
{
|
|
struct hlist_node *node;
|
|
struct sock *s = sk;
|
|
unsigned short hnum = ntohs(loc_port);
|
|
|
|
sk_for_each_from(s, node) {
|
|
struct inet_sock *inet = inet_sk(s);
|
|
|
|
if (s->sk_hash != hnum ||
|
|
(inet->daddr && inet->daddr != rmt_addr) ||
|
|
(inet->dport != rmt_port && inet->dport) ||
|
|
(inet->rcv_saddr && inet->rcv_saddr != loc_addr) ||
|
|
ipv6_only_sock(s) ||
|
|
(s->sk_bound_dev_if && s->sk_bound_dev_if != dif))
|
|
continue;
|
|
if (!ip_mc_sf_allow(s, loc_addr, rmt_addr, dif))
|
|
continue;
|
|
goto found;
|
|
}
|
|
s = NULL;
|
|
found:
|
|
return s;
|
|
}
|
|
|
|
/*
|
|
* This routine is called by the ICMP module when it gets some
|
|
* sort of error condition. If err < 0 then the socket should
|
|
* be closed and the error returned to the user. If err > 0
|
|
* it's just the icmp type << 8 | icmp code.
|
|
* Header points to the ip header of the error packet. We move
|
|
* on past this. Then (as it used to claim before adjustment)
|
|
* header points to the first 8 bytes of the udp header. We need
|
|
* to find the appropriate port.
|
|
*/
|
|
|
|
void __udp4_lib_err(struct sk_buff *skb, u32 info, struct hlist_head udptable[])
|
|
{
|
|
struct inet_sock *inet;
|
|
struct iphdr *iph = (struct iphdr*)skb->data;
|
|
struct udphdr *uh = (struct udphdr*)(skb->data+(iph->ihl<<2));
|
|
const int type = icmp_hdr(skb)->type;
|
|
const int code = icmp_hdr(skb)->code;
|
|
struct sock *sk;
|
|
int harderr;
|
|
int err;
|
|
|
|
sk = __udp4_lib_lookup(skb->dev->nd_net, iph->daddr, uh->dest,
|
|
iph->saddr, uh->source, skb->dev->ifindex, udptable);
|
|
if (sk == NULL) {
|
|
ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
|
|
return; /* No socket for error */
|
|
}
|
|
|
|
err = 0;
|
|
harderr = 0;
|
|
inet = inet_sk(sk);
|
|
|
|
switch (type) {
|
|
default:
|
|
case ICMP_TIME_EXCEEDED:
|
|
err = EHOSTUNREACH;
|
|
break;
|
|
case ICMP_SOURCE_QUENCH:
|
|
goto out;
|
|
case ICMP_PARAMETERPROB:
|
|
err = EPROTO;
|
|
harderr = 1;
|
|
break;
|
|
case ICMP_DEST_UNREACH:
|
|
if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
|
|
if (inet->pmtudisc != IP_PMTUDISC_DONT) {
|
|
err = EMSGSIZE;
|
|
harderr = 1;
|
|
break;
|
|
}
|
|
goto out;
|
|
}
|
|
err = EHOSTUNREACH;
|
|
if (code <= NR_ICMP_UNREACH) {
|
|
harderr = icmp_err_convert[code].fatal;
|
|
err = icmp_err_convert[code].errno;
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* RFC1122: OK. Passes ICMP errors back to application, as per
|
|
* 4.1.3.3.
|
|
*/
|
|
if (!inet->recverr) {
|
|
if (!harderr || sk->sk_state != TCP_ESTABLISHED)
|
|
goto out;
|
|
} else {
|
|
ip_icmp_error(sk, skb, err, uh->dest, info, (u8*)(uh+1));
|
|
}
|
|
sk->sk_err = err;
|
|
sk->sk_error_report(sk);
|
|
out:
|
|
sock_put(sk);
|
|
}
|
|
|
|
void udp_err(struct sk_buff *skb, u32 info)
|
|
{
|
|
__udp4_lib_err(skb, info, udp_hash);
|
|
}
|
|
|
|
/*
|
|
* Throw away all pending data and cancel the corking. Socket is locked.
|
|
*/
|
|
static void udp_flush_pending_frames(struct sock *sk)
|
|
{
|
|
struct udp_sock *up = udp_sk(sk);
|
|
|
|
if (up->pending) {
|
|
up->len = 0;
|
|
up->pending = 0;
|
|
ip_flush_pending_frames(sk);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* udp4_hwcsum_outgoing - handle outgoing HW checksumming
|
|
* @sk: socket we are sending on
|
|
* @skb: sk_buff containing the filled-in UDP header
|
|
* (checksum field must be zeroed out)
|
|
*/
|
|
static void udp4_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
|
|
__be32 src, __be32 dst, int len )
|
|
{
|
|
unsigned int offset;
|
|
struct udphdr *uh = udp_hdr(skb);
|
|
__wsum csum = 0;
|
|
|
|
if (skb_queue_len(&sk->sk_write_queue) == 1) {
|
|
/*
|
|
* Only one fragment on the socket.
|
|
*/
|
|
skb->csum_start = skb_transport_header(skb) - skb->head;
|
|
skb->csum_offset = offsetof(struct udphdr, check);
|
|
uh->check = ~csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, 0);
|
|
} else {
|
|
/*
|
|
* HW-checksum won't work as there are two or more
|
|
* fragments on the socket so that all csums of sk_buffs
|
|
* should be together
|
|
*/
|
|
offset = skb_transport_offset(skb);
|
|
skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
|
|
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
|
|
skb_queue_walk(&sk->sk_write_queue, skb) {
|
|
csum = csum_add(csum, skb->csum);
|
|
}
|
|
|
|
uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum);
|
|
if (uh->check == 0)
|
|
uh->check = CSUM_MANGLED_0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Push out all pending data as one UDP datagram. Socket is locked.
|
|
*/
|
|
static int udp_push_pending_frames(struct sock *sk)
|
|
{
|
|
struct udp_sock *up = udp_sk(sk);
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
struct flowi *fl = &inet->cork.fl;
|
|
struct sk_buff *skb;
|
|
struct udphdr *uh;
|
|
int err = 0;
|
|
int is_udplite = IS_UDPLITE(sk);
|
|
__wsum csum = 0;
|
|
|
|
/* Grab the skbuff where UDP header space exists. */
|
|
if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
|
|
goto out;
|
|
|
|
/*
|
|
* Create a UDP header
|
|
*/
|
|
uh = udp_hdr(skb);
|
|
uh->source = fl->fl_ip_sport;
|
|
uh->dest = fl->fl_ip_dport;
|
|
uh->len = htons(up->len);
|
|
uh->check = 0;
|
|
|
|
if (is_udplite) /* UDP-Lite */
|
|
csum = udplite_csum_outgoing(sk, skb);
|
|
|
|
else if (sk->sk_no_check == UDP_CSUM_NOXMIT) { /* UDP csum disabled */
|
|
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
goto send;
|
|
|
|
} else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
|
|
|
|
udp4_hwcsum_outgoing(sk, skb, fl->fl4_src,fl->fl4_dst, up->len);
|
|
goto send;
|
|
|
|
} else /* `normal' UDP */
|
|
csum = udp_csum_outgoing(sk, skb);
|
|
|
|
/* add protocol-dependent pseudo-header */
|
|
uh->check = csum_tcpudp_magic(fl->fl4_src, fl->fl4_dst, up->len,
|
|
sk->sk_protocol, csum );
|
|
if (uh->check == 0)
|
|
uh->check = CSUM_MANGLED_0;
|
|
|
|
send:
|
|
err = ip_push_pending_frames(sk);
|
|
out:
|
|
up->len = 0;
|
|
up->pending = 0;
|
|
if (!err)
|
|
UDP_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS, is_udplite);
|
|
return err;
|
|
}
|
|
|
|
int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
|
|
size_t len)
|
|
{
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
struct udp_sock *up = udp_sk(sk);
|
|
int ulen = len;
|
|
struct ipcm_cookie ipc;
|
|
struct rtable *rt = NULL;
|
|
int free = 0;
|
|
int connected = 0;
|
|
__be32 daddr, faddr, saddr;
|
|
__be16 dport;
|
|
u8 tos;
|
|
int err, is_udplite = IS_UDPLITE(sk);
|
|
int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
|
|
int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
|
|
|
|
if (len > 0xFFFF)
|
|
return -EMSGSIZE;
|
|
|
|
/*
|
|
* Check the flags.
|
|
*/
|
|
|
|
if (msg->msg_flags&MSG_OOB) /* Mirror BSD error message compatibility */
|
|
return -EOPNOTSUPP;
|
|
|
|
ipc.opt = NULL;
|
|
|
|
if (up->pending) {
|
|
/*
|
|
* There are pending frames.
|
|
* The socket lock must be held while it's corked.
|
|
*/
|
|
lock_sock(sk);
|
|
if (likely(up->pending)) {
|
|
if (unlikely(up->pending != AF_INET)) {
|
|
release_sock(sk);
|
|
return -EINVAL;
|
|
}
|
|
goto do_append_data;
|
|
}
|
|
release_sock(sk);
|
|
}
|
|
ulen += sizeof(struct udphdr);
|
|
|
|
/*
|
|
* Get and verify the address.
|
|
*/
|
|
if (msg->msg_name) {
|
|
struct sockaddr_in * usin = (struct sockaddr_in*)msg->msg_name;
|
|
if (msg->msg_namelen < sizeof(*usin))
|
|
return -EINVAL;
|
|
if (usin->sin_family != AF_INET) {
|
|
if (usin->sin_family != AF_UNSPEC)
|
|
return -EAFNOSUPPORT;
|
|
}
|
|
|
|
daddr = usin->sin_addr.s_addr;
|
|
dport = usin->sin_port;
|
|
if (dport == 0)
|
|
return -EINVAL;
|
|
} else {
|
|
if (sk->sk_state != TCP_ESTABLISHED)
|
|
return -EDESTADDRREQ;
|
|
daddr = inet->daddr;
|
|
dport = inet->dport;
|
|
/* Open fast path for connected socket.
|
|
Route will not be used, if at least one option is set.
|
|
*/
|
|
connected = 1;
|
|
}
|
|
ipc.addr = inet->saddr;
|
|
|
|
ipc.oif = sk->sk_bound_dev_if;
|
|
if (msg->msg_controllen) {
|
|
err = ip_cmsg_send(&init_net, msg, &ipc);
|
|
if (err)
|
|
return err;
|
|
if (ipc.opt)
|
|
free = 1;
|
|
connected = 0;
|
|
}
|
|
if (!ipc.opt)
|
|
ipc.opt = inet->opt;
|
|
|
|
saddr = ipc.addr;
|
|
ipc.addr = faddr = daddr;
|
|
|
|
if (ipc.opt && ipc.opt->srr) {
|
|
if (!daddr)
|
|
return -EINVAL;
|
|
faddr = ipc.opt->faddr;
|
|
connected = 0;
|
|
}
|
|
tos = RT_TOS(inet->tos);
|
|
if (sock_flag(sk, SOCK_LOCALROUTE) ||
|
|
(msg->msg_flags & MSG_DONTROUTE) ||
|
|
(ipc.opt && ipc.opt->is_strictroute)) {
|
|
tos |= RTO_ONLINK;
|
|
connected = 0;
|
|
}
|
|
|
|
if (ipv4_is_multicast(daddr)) {
|
|
if (!ipc.oif)
|
|
ipc.oif = inet->mc_index;
|
|
if (!saddr)
|
|
saddr = inet->mc_addr;
|
|
connected = 0;
|
|
}
|
|
|
|
if (connected)
|
|
rt = (struct rtable*)sk_dst_check(sk, 0);
|
|
|
|
if (rt == NULL) {
|
|
struct flowi fl = { .oif = ipc.oif,
|
|
.nl_u = { .ip4_u =
|
|
{ .daddr = faddr,
|
|
.saddr = saddr,
|
|
.tos = tos } },
|
|
.proto = sk->sk_protocol,
|
|
.uli_u = { .ports =
|
|
{ .sport = inet->sport,
|
|
.dport = dport } } };
|
|
security_sk_classify_flow(sk, &fl);
|
|
err = ip_route_output_flow(&init_net, &rt, &fl, sk, 1);
|
|
if (err) {
|
|
if (err == -ENETUNREACH)
|
|
IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
|
|
goto out;
|
|
}
|
|
|
|
err = -EACCES;
|
|
if ((rt->rt_flags & RTCF_BROADCAST) &&
|
|
!sock_flag(sk, SOCK_BROADCAST))
|
|
goto out;
|
|
if (connected)
|
|
sk_dst_set(sk, dst_clone(&rt->u.dst));
|
|
}
|
|
|
|
if (msg->msg_flags&MSG_CONFIRM)
|
|
goto do_confirm;
|
|
back_from_confirm:
|
|
|
|
saddr = rt->rt_src;
|
|
if (!ipc.addr)
|
|
daddr = ipc.addr = rt->rt_dst;
|
|
|
|
lock_sock(sk);
|
|
if (unlikely(up->pending)) {
|
|
/* The socket is already corked while preparing it. */
|
|
/* ... which is an evident application bug. --ANK */
|
|
release_sock(sk);
|
|
|
|
LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
/*
|
|
* Now cork the socket to pend data.
|
|
*/
|
|
inet->cork.fl.fl4_dst = daddr;
|
|
inet->cork.fl.fl_ip_dport = dport;
|
|
inet->cork.fl.fl4_src = saddr;
|
|
inet->cork.fl.fl_ip_sport = inet->sport;
|
|
up->pending = AF_INET;
|
|
|
|
do_append_data:
|
|
up->len += ulen;
|
|
getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
|
|
err = ip_append_data(sk, getfrag, msg->msg_iov, ulen,
|
|
sizeof(struct udphdr), &ipc, rt,
|
|
corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
|
|
if (err)
|
|
udp_flush_pending_frames(sk);
|
|
else if (!corkreq)
|
|
err = udp_push_pending_frames(sk);
|
|
else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
|
|
up->pending = 0;
|
|
release_sock(sk);
|
|
|
|
out:
|
|
ip_rt_put(rt);
|
|
if (free)
|
|
kfree(ipc.opt);
|
|
if (!err)
|
|
return len;
|
|
/*
|
|
* ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
|
|
* ENOBUFS might not be good (it's not tunable per se), but otherwise
|
|
* we don't have a good statistic (IpOutDiscards but it can be too many
|
|
* things). We could add another new stat but at least for now that
|
|
* seems like overkill.
|
|
*/
|
|
if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
|
|
UDP_INC_STATS_USER(UDP_MIB_SNDBUFERRORS, is_udplite);
|
|
}
|
|
return err;
|
|
|
|
do_confirm:
|
|
dst_confirm(&rt->u.dst);
|
|
if (!(msg->msg_flags&MSG_PROBE) || len)
|
|
goto back_from_confirm;
|
|
err = 0;
|
|
goto out;
|
|
}
|
|
|
|
int udp_sendpage(struct sock *sk, struct page *page, int offset,
|
|
size_t size, int flags)
|
|
{
|
|
struct udp_sock *up = udp_sk(sk);
|
|
int ret;
|
|
|
|
if (!up->pending) {
|
|
struct msghdr msg = { .msg_flags = flags|MSG_MORE };
|
|
|
|
/* Call udp_sendmsg to specify destination address which
|
|
* sendpage interface can't pass.
|
|
* This will succeed only when the socket is connected.
|
|
*/
|
|
ret = udp_sendmsg(NULL, sk, &msg, 0);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
|
|
lock_sock(sk);
|
|
|
|
if (unlikely(!up->pending)) {
|
|
release_sock(sk);
|
|
|
|
LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 3\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = ip_append_page(sk, page, offset, size, flags);
|
|
if (ret == -EOPNOTSUPP) {
|
|
release_sock(sk);
|
|
return sock_no_sendpage(sk->sk_socket, page, offset,
|
|
size, flags);
|
|
}
|
|
if (ret < 0) {
|
|
udp_flush_pending_frames(sk);
|
|
goto out;
|
|
}
|
|
|
|
up->len += size;
|
|
if (!(up->corkflag || (flags&MSG_MORE)))
|
|
ret = udp_push_pending_frames(sk);
|
|
if (!ret)
|
|
ret = size;
|
|
out:
|
|
release_sock(sk);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* IOCTL requests applicable to the UDP protocol
|
|
*/
|
|
|
|
int udp_ioctl(struct sock *sk, int cmd, unsigned long arg)
|
|
{
|
|
switch (cmd) {
|
|
case SIOCOUTQ:
|
|
{
|
|
int amount = atomic_read(&sk->sk_wmem_alloc);
|
|
return put_user(amount, (int __user *)arg);
|
|
}
|
|
|
|
case SIOCINQ:
|
|
{
|
|
struct sk_buff *skb;
|
|
unsigned long amount;
|
|
|
|
amount = 0;
|
|
spin_lock_bh(&sk->sk_receive_queue.lock);
|
|
skb = skb_peek(&sk->sk_receive_queue);
|
|
if (skb != NULL) {
|
|
/*
|
|
* We will only return the amount
|
|
* of this packet since that is all
|
|
* that will be read.
|
|
*/
|
|
amount = skb->len - sizeof(struct udphdr);
|
|
}
|
|
spin_unlock_bh(&sk->sk_receive_queue.lock);
|
|
return put_user(amount, (int __user *)arg);
|
|
}
|
|
|
|
default:
|
|
return -ENOIOCTLCMD;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This should be easy, if there is something there we
|
|
* return it, otherwise we block.
|
|
*/
|
|
|
|
int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
|
|
size_t len, int noblock, int flags, int *addr_len)
|
|
{
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
|
|
struct sk_buff *skb;
|
|
unsigned int ulen, copied;
|
|
int peeked;
|
|
int err;
|
|
int is_udplite = IS_UDPLITE(sk);
|
|
|
|
/*
|
|
* Check any passed addresses
|
|
*/
|
|
if (addr_len)
|
|
*addr_len=sizeof(*sin);
|
|
|
|
if (flags & MSG_ERRQUEUE)
|
|
return ip_recv_error(sk, msg, len);
|
|
|
|
try_again:
|
|
skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
|
|
&peeked, &err);
|
|
if (!skb)
|
|
goto out;
|
|
|
|
ulen = skb->len - sizeof(struct udphdr);
|
|
copied = len;
|
|
if (copied > ulen)
|
|
copied = ulen;
|
|
else if (copied < ulen)
|
|
msg->msg_flags |= MSG_TRUNC;
|
|
|
|
/*
|
|
* If checksum is needed at all, try to do it while copying the
|
|
* data. If the data is truncated, or if we only want a partial
|
|
* coverage checksum (UDP-Lite), do it before the copy.
|
|
*/
|
|
|
|
if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
|
|
if (udp_lib_checksum_complete(skb))
|
|
goto csum_copy_err;
|
|
}
|
|
|
|
if (skb_csum_unnecessary(skb))
|
|
err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
|
|
msg->msg_iov, copied );
|
|
else {
|
|
err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
|
|
|
|
if (err == -EINVAL)
|
|
goto csum_copy_err;
|
|
}
|
|
|
|
if (err)
|
|
goto out_free;
|
|
|
|
if (!peeked)
|
|
UDP_INC_STATS_USER(UDP_MIB_INDATAGRAMS, is_udplite);
|
|
|
|
sock_recv_timestamp(msg, sk, skb);
|
|
|
|
/* Copy the address. */
|
|
if (sin)
|
|
{
|
|
sin->sin_family = AF_INET;
|
|
sin->sin_port = udp_hdr(skb)->source;
|
|
sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
|
|
memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
|
|
}
|
|
if (inet->cmsg_flags)
|
|
ip_cmsg_recv(msg, skb);
|
|
|
|
err = copied;
|
|
if (flags & MSG_TRUNC)
|
|
err = ulen;
|
|
|
|
out_free:
|
|
lock_sock(sk);
|
|
skb_free_datagram(sk, skb);
|
|
release_sock(sk);
|
|
out:
|
|
return err;
|
|
|
|
csum_copy_err:
|
|
lock_sock(sk);
|
|
if (!skb_kill_datagram(sk, skb, flags))
|
|
UDP_INC_STATS_USER(UDP_MIB_INERRORS, is_udplite);
|
|
release_sock(sk);
|
|
|
|
if (noblock)
|
|
return -EAGAIN;
|
|
goto try_again;
|
|
}
|
|
|
|
|
|
int udp_disconnect(struct sock *sk, int flags)
|
|
{
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
/*
|
|
* 1003.1g - break association.
|
|
*/
|
|
|
|
sk->sk_state = TCP_CLOSE;
|
|
inet->daddr = 0;
|
|
inet->dport = 0;
|
|
sk->sk_bound_dev_if = 0;
|
|
if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
|
|
inet_reset_saddr(sk);
|
|
|
|
if (!(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) {
|
|
sk->sk_prot->unhash(sk);
|
|
inet->sport = 0;
|
|
}
|
|
sk_dst_reset(sk);
|
|
return 0;
|
|
}
|
|
|
|
/* returns:
|
|
* -1: error
|
|
* 0: success
|
|
* >0: "udp encap" protocol resubmission
|
|
*
|
|
* Note that in the success and error cases, the skb is assumed to
|
|
* have either been requeued or freed.
|
|
*/
|
|
int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
|
|
{
|
|
struct udp_sock *up = udp_sk(sk);
|
|
int rc;
|
|
int is_udplite = IS_UDPLITE(sk);
|
|
|
|
/*
|
|
* Charge it to the socket, dropping if the queue is full.
|
|
*/
|
|
if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
|
|
goto drop;
|
|
nf_reset(skb);
|
|
|
|
if (up->encap_type) {
|
|
/*
|
|
* This is an encapsulation socket so pass the skb to
|
|
* the socket's udp_encap_rcv() hook. Otherwise, just
|
|
* fall through and pass this up the UDP socket.
|
|
* up->encap_rcv() returns the following value:
|
|
* =0 if skb was successfully passed to the encap
|
|
* handler or was discarded by it.
|
|
* >0 if skb should be passed on to UDP.
|
|
* <0 if skb should be resubmitted as proto -N
|
|
*/
|
|
|
|
/* if we're overly short, let UDP handle it */
|
|
if (skb->len > sizeof(struct udphdr) &&
|
|
up->encap_rcv != NULL) {
|
|
int ret;
|
|
|
|
ret = (*up->encap_rcv)(sk, skb);
|
|
if (ret <= 0) {
|
|
UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS,
|
|
is_udplite);
|
|
return -ret;
|
|
}
|
|
}
|
|
|
|
/* FALLTHROUGH -- it's a UDP Packet */
|
|
}
|
|
|
|
/*
|
|
* UDP-Lite specific tests, ignored on UDP sockets
|
|
*/
|
|
if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
|
|
|
|
/*
|
|
* MIB statistics other than incrementing the error count are
|
|
* disabled for the following two types of errors: these depend
|
|
* on the application settings, not on the functioning of the
|
|
* protocol stack as such.
|
|
*
|
|
* RFC 3828 here recommends (sec 3.3): "There should also be a
|
|
* way ... to ... at least let the receiving application block
|
|
* delivery of packets with coverage values less than a value
|
|
* provided by the application."
|
|
*/
|
|
if (up->pcrlen == 0) { /* full coverage was set */
|
|
LIMIT_NETDEBUG(KERN_WARNING "UDPLITE: partial coverage "
|
|
"%d while full coverage %d requested\n",
|
|
UDP_SKB_CB(skb)->cscov, skb->len);
|
|
goto drop;
|
|
}
|
|
/* The next case involves violating the min. coverage requested
|
|
* by the receiver. This is subtle: if receiver wants x and x is
|
|
* greater than the buffersize/MTU then receiver will complain
|
|
* that it wants x while sender emits packets of smaller size y.
|
|
* Therefore the above ...()->partial_cov statement is essential.
|
|
*/
|
|
if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
|
|
LIMIT_NETDEBUG(KERN_WARNING
|
|
"UDPLITE: coverage %d too small, need min %d\n",
|
|
UDP_SKB_CB(skb)->cscov, up->pcrlen);
|
|
goto drop;
|
|
}
|
|
}
|
|
|
|
if (sk->sk_filter) {
|
|
if (udp_lib_checksum_complete(skb))
|
|
goto drop;
|
|
}
|
|
|
|
if ((rc = sock_queue_rcv_skb(sk,skb)) < 0) {
|
|
/* Note that an ENOMEM error is charged twice */
|
|
if (rc == -ENOMEM)
|
|
UDP_INC_STATS_BH(UDP_MIB_RCVBUFERRORS, is_udplite);
|
|
goto drop;
|
|
}
|
|
|
|
return 0;
|
|
|
|
drop:
|
|
UDP_INC_STATS_BH(UDP_MIB_INERRORS, is_udplite);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Multicasts and broadcasts go to each listener.
|
|
*
|
|
* Note: called only from the BH handler context,
|
|
* so we don't need to lock the hashes.
|
|
*/
|
|
static int __udp4_lib_mcast_deliver(struct sk_buff *skb,
|
|
struct udphdr *uh,
|
|
__be32 saddr, __be32 daddr,
|
|
struct hlist_head udptable[])
|
|
{
|
|
struct sock *sk;
|
|
int dif;
|
|
|
|
read_lock(&udp_hash_lock);
|
|
sk = sk_head(&udptable[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]);
|
|
dif = skb->dev->ifindex;
|
|
sk = udp_v4_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif);
|
|
if (sk) {
|
|
struct sock *sknext = NULL;
|
|
|
|
do {
|
|
struct sk_buff *skb1 = skb;
|
|
|
|
sknext = udp_v4_mcast_next(sk_next(sk), uh->dest, daddr,
|
|
uh->source, saddr, dif);
|
|
if (sknext)
|
|
skb1 = skb_clone(skb, GFP_ATOMIC);
|
|
|
|
if (skb1) {
|
|
int ret = 0;
|
|
|
|
bh_lock_sock_nested(sk);
|
|
if (!sock_owned_by_user(sk))
|
|
ret = udp_queue_rcv_skb(sk, skb1);
|
|
else
|
|
sk_add_backlog(sk, skb1);
|
|
bh_unlock_sock(sk);
|
|
|
|
if (ret > 0)
|
|
/* we should probably re-process instead
|
|
* of dropping packets here. */
|
|
kfree_skb(skb1);
|
|
}
|
|
sk = sknext;
|
|
} while (sknext);
|
|
} else
|
|
kfree_skb(skb);
|
|
read_unlock(&udp_hash_lock);
|
|
return 0;
|
|
}
|
|
|
|
/* Initialize UDP checksum. If exited with zero value (success),
|
|
* CHECKSUM_UNNECESSARY means, that no more checks are required.
|
|
* Otherwise, csum completion requires chacksumming packet body,
|
|
* including udp header and folding it to skb->csum.
|
|
*/
|
|
static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh,
|
|
int proto)
|
|
{
|
|
const struct iphdr *iph;
|
|
int err;
|
|
|
|
UDP_SKB_CB(skb)->partial_cov = 0;
|
|
UDP_SKB_CB(skb)->cscov = skb->len;
|
|
|
|
if (proto == IPPROTO_UDPLITE) {
|
|
err = udplite_checksum_init(skb, uh);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
iph = ip_hdr(skb);
|
|
if (uh->check == 0) {
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
} else if (skb->ip_summed == CHECKSUM_COMPLETE) {
|
|
if (!csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len,
|
|
proto, skb->csum))
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
}
|
|
if (!skb_csum_unnecessary(skb))
|
|
skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr,
|
|
skb->len, proto, 0);
|
|
/* Probably, we should checksum udp header (it should be in cache
|
|
* in any case) and data in tiny packets (< rx copybreak).
|
|
*/
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* All we need to do is get the socket, and then do a checksum.
|
|
*/
|
|
|
|
int __udp4_lib_rcv(struct sk_buff *skb, struct hlist_head udptable[],
|
|
int proto)
|
|
{
|
|
struct sock *sk;
|
|
struct udphdr *uh = udp_hdr(skb);
|
|
unsigned short ulen;
|
|
struct rtable *rt = (struct rtable*)skb->dst;
|
|
__be32 saddr = ip_hdr(skb)->saddr;
|
|
__be32 daddr = ip_hdr(skb)->daddr;
|
|
|
|
/*
|
|
* Validate the packet.
|
|
*/
|
|
if (!pskb_may_pull(skb, sizeof(struct udphdr)))
|
|
goto drop; /* No space for header. */
|
|
|
|
ulen = ntohs(uh->len);
|
|
if (ulen > skb->len)
|
|
goto short_packet;
|
|
|
|
if (proto == IPPROTO_UDP) {
|
|
/* UDP validates ulen. */
|
|
if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen))
|
|
goto short_packet;
|
|
uh = udp_hdr(skb);
|
|
}
|
|
|
|
if (udp4_csum_init(skb, uh, proto))
|
|
goto csum_error;
|
|
|
|
if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
|
|
return __udp4_lib_mcast_deliver(skb, uh, saddr, daddr, udptable);
|
|
|
|
sk = __udp4_lib_lookup(skb->dev->nd_net, saddr, uh->source, daddr,
|
|
uh->dest, inet_iif(skb), udptable);
|
|
|
|
if (sk != NULL) {
|
|
int ret = 0;
|
|
bh_lock_sock_nested(sk);
|
|
if (!sock_owned_by_user(sk))
|
|
ret = udp_queue_rcv_skb(sk, skb);
|
|
else
|
|
sk_add_backlog(sk, skb);
|
|
bh_unlock_sock(sk);
|
|
sock_put(sk);
|
|
|
|
/* a return value > 0 means to resubmit the input, but
|
|
* it wants the return to be -protocol, or 0
|
|
*/
|
|
if (ret > 0)
|
|
return -ret;
|
|
return 0;
|
|
}
|
|
|
|
if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
|
|
goto drop;
|
|
nf_reset(skb);
|
|
|
|
/* No socket. Drop packet silently, if checksum is wrong */
|
|
if (udp_lib_checksum_complete(skb))
|
|
goto csum_error;
|
|
|
|
UDP_INC_STATS_BH(UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
|
|
|
|
/*
|
|
* Hmm. We got an UDP packet to a port to which we
|
|
* don't wanna listen. Ignore it.
|
|
*/
|
|
kfree_skb(skb);
|
|
return 0;
|
|
|
|
short_packet:
|
|
LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: short packet: From %u.%u.%u.%u:%u %d/%d to %u.%u.%u.%u:%u\n",
|
|
proto == IPPROTO_UDPLITE ? "-Lite" : "",
|
|
NIPQUAD(saddr),
|
|
ntohs(uh->source),
|
|
ulen,
|
|
skb->len,
|
|
NIPQUAD(daddr),
|
|
ntohs(uh->dest));
|
|
goto drop;
|
|
|
|
csum_error:
|
|
/*
|
|
* RFC1122: OK. Discards the bad packet silently (as far as
|
|
* the network is concerned, anyway) as per 4.1.3.4 (MUST).
|
|
*/
|
|
LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: bad checksum. From %d.%d.%d.%d:%d to %d.%d.%d.%d:%d ulen %d\n",
|
|
proto == IPPROTO_UDPLITE ? "-Lite" : "",
|
|
NIPQUAD(saddr),
|
|
ntohs(uh->source),
|
|
NIPQUAD(daddr),
|
|
ntohs(uh->dest),
|
|
ulen);
|
|
drop:
|
|
UDP_INC_STATS_BH(UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
int udp_rcv(struct sk_buff *skb)
|
|
{
|
|
return __udp4_lib_rcv(skb, udp_hash, IPPROTO_UDP);
|
|
}
|
|
|
|
int udp_destroy_sock(struct sock *sk)
|
|
{
|
|
lock_sock(sk);
|
|
udp_flush_pending_frames(sk);
|
|
release_sock(sk);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Socket option code for UDP
|
|
*/
|
|
int udp_lib_setsockopt(struct sock *sk, int level, int optname,
|
|
char __user *optval, int optlen,
|
|
int (*push_pending_frames)(struct sock *))
|
|
{
|
|
struct udp_sock *up = udp_sk(sk);
|
|
int val;
|
|
int err = 0;
|
|
int is_udplite = IS_UDPLITE(sk);
|
|
|
|
if (optlen<sizeof(int))
|
|
return -EINVAL;
|
|
|
|
if (get_user(val, (int __user *)optval))
|
|
return -EFAULT;
|
|
|
|
switch (optname) {
|
|
case UDP_CORK:
|
|
if (val != 0) {
|
|
up->corkflag = 1;
|
|
} else {
|
|
up->corkflag = 0;
|
|
lock_sock(sk);
|
|
(*push_pending_frames)(sk);
|
|
release_sock(sk);
|
|
}
|
|
break;
|
|
|
|
case UDP_ENCAP:
|
|
switch (val) {
|
|
case 0:
|
|
case UDP_ENCAP_ESPINUDP:
|
|
case UDP_ENCAP_ESPINUDP_NON_IKE:
|
|
up->encap_rcv = xfrm4_udp_encap_rcv;
|
|
/* FALLTHROUGH */
|
|
case UDP_ENCAP_L2TPINUDP:
|
|
up->encap_type = val;
|
|
break;
|
|
default:
|
|
err = -ENOPROTOOPT;
|
|
break;
|
|
}
|
|
break;
|
|
|
|
/*
|
|
* UDP-Lite's partial checksum coverage (RFC 3828).
|
|
*/
|
|
/* The sender sets actual checksum coverage length via this option.
|
|
* The case coverage > packet length is handled by send module. */
|
|
case UDPLITE_SEND_CSCOV:
|
|
if (!is_udplite) /* Disable the option on UDP sockets */
|
|
return -ENOPROTOOPT;
|
|
if (val != 0 && val < 8) /* Illegal coverage: use default (8) */
|
|
val = 8;
|
|
up->pcslen = val;
|
|
up->pcflag |= UDPLITE_SEND_CC;
|
|
break;
|
|
|
|
/* The receiver specifies a minimum checksum coverage value. To make
|
|
* sense, this should be set to at least 8 (as done below). If zero is
|
|
* used, this again means full checksum coverage. */
|
|
case UDPLITE_RECV_CSCOV:
|
|
if (!is_udplite) /* Disable the option on UDP sockets */
|
|
return -ENOPROTOOPT;
|
|
if (val != 0 && val < 8) /* Avoid silly minimal values. */
|
|
val = 8;
|
|
up->pcrlen = val;
|
|
up->pcflag |= UDPLITE_RECV_CC;
|
|
break;
|
|
|
|
default:
|
|
err = -ENOPROTOOPT;
|
|
break;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
int udp_setsockopt(struct sock *sk, int level, int optname,
|
|
char __user *optval, int optlen)
|
|
{
|
|
if (level == SOL_UDP || level == SOL_UDPLITE)
|
|
return udp_lib_setsockopt(sk, level, optname, optval, optlen,
|
|
udp_push_pending_frames);
|
|
return ip_setsockopt(sk, level, optname, optval, optlen);
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
int compat_udp_setsockopt(struct sock *sk, int level, int optname,
|
|
char __user *optval, int optlen)
|
|
{
|
|
if (level == SOL_UDP || level == SOL_UDPLITE)
|
|
return udp_lib_setsockopt(sk, level, optname, optval, optlen,
|
|
udp_push_pending_frames);
|
|
return compat_ip_setsockopt(sk, level, optname, optval, optlen);
|
|
}
|
|
#endif
|
|
|
|
int udp_lib_getsockopt(struct sock *sk, int level, int optname,
|
|
char __user *optval, int __user *optlen)
|
|
{
|
|
struct udp_sock *up = udp_sk(sk);
|
|
int val, len;
|
|
|
|
if (get_user(len,optlen))
|
|
return -EFAULT;
|
|
|
|
len = min_t(unsigned int, len, sizeof(int));
|
|
|
|
if (len < 0)
|
|
return -EINVAL;
|
|
|
|
switch (optname) {
|
|
case UDP_CORK:
|
|
val = up->corkflag;
|
|
break;
|
|
|
|
case UDP_ENCAP:
|
|
val = up->encap_type;
|
|
break;
|
|
|
|
/* The following two cannot be changed on UDP sockets, the return is
|
|
* always 0 (which corresponds to the full checksum coverage of UDP). */
|
|
case UDPLITE_SEND_CSCOV:
|
|
val = up->pcslen;
|
|
break;
|
|
|
|
case UDPLITE_RECV_CSCOV:
|
|
val = up->pcrlen;
|
|
break;
|
|
|
|
default:
|
|
return -ENOPROTOOPT;
|
|
}
|
|
|
|
if (put_user(len, optlen))
|
|
return -EFAULT;
|
|
if (copy_to_user(optval, &val,len))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
int udp_getsockopt(struct sock *sk, int level, int optname,
|
|
char __user *optval, int __user *optlen)
|
|
{
|
|
if (level == SOL_UDP || level == SOL_UDPLITE)
|
|
return udp_lib_getsockopt(sk, level, optname, optval, optlen);
|
|
return ip_getsockopt(sk, level, optname, optval, optlen);
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
int compat_udp_getsockopt(struct sock *sk, int level, int optname,
|
|
char __user *optval, int __user *optlen)
|
|
{
|
|
if (level == SOL_UDP || level == SOL_UDPLITE)
|
|
return udp_lib_getsockopt(sk, level, optname, optval, optlen);
|
|
return compat_ip_getsockopt(sk, level, optname, optval, optlen);
|
|
}
|
|
#endif
|
|
/**
|
|
* udp_poll - wait for a UDP event.
|
|
* @file - file struct
|
|
* @sock - socket
|
|
* @wait - poll table
|
|
*
|
|
* This is same as datagram poll, except for the special case of
|
|
* blocking sockets. If application is using a blocking fd
|
|
* and a packet with checksum error is in the queue;
|
|
* then it could get return from select indicating data available
|
|
* but then block when reading it. Add special case code
|
|
* to work around these arguably broken applications.
|
|
*/
|
|
unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait)
|
|
{
|
|
unsigned int mask = datagram_poll(file, sock, wait);
|
|
struct sock *sk = sock->sk;
|
|
int is_lite = IS_UDPLITE(sk);
|
|
|
|
/* Check for false positives due to checksum errors */
|
|
if ( (mask & POLLRDNORM) &&
|
|
!(file->f_flags & O_NONBLOCK) &&
|
|
!(sk->sk_shutdown & RCV_SHUTDOWN)){
|
|
struct sk_buff_head *rcvq = &sk->sk_receive_queue;
|
|
struct sk_buff *skb;
|
|
|
|
spin_lock_bh(&rcvq->lock);
|
|
while ((skb = skb_peek(rcvq)) != NULL &&
|
|
udp_lib_checksum_complete(skb)) {
|
|
UDP_INC_STATS_BH(UDP_MIB_INERRORS, is_lite);
|
|
__skb_unlink(skb, rcvq);
|
|
kfree_skb(skb);
|
|
}
|
|
spin_unlock_bh(&rcvq->lock);
|
|
|
|
/* nothing to see, move along */
|
|
if (skb == NULL)
|
|
mask &= ~(POLLIN | POLLRDNORM);
|
|
}
|
|
|
|
return mask;
|
|
|
|
}
|
|
|
|
DEFINE_PROTO_INUSE(udp)
|
|
|
|
struct proto udp_prot = {
|
|
.name = "UDP",
|
|
.owner = THIS_MODULE,
|
|
.close = udp_lib_close,
|
|
.connect = ip4_datagram_connect,
|
|
.disconnect = udp_disconnect,
|
|
.ioctl = udp_ioctl,
|
|
.destroy = udp_destroy_sock,
|
|
.setsockopt = udp_setsockopt,
|
|
.getsockopt = udp_getsockopt,
|
|
.sendmsg = udp_sendmsg,
|
|
.recvmsg = udp_recvmsg,
|
|
.sendpage = udp_sendpage,
|
|
.backlog_rcv = udp_queue_rcv_skb,
|
|
.hash = udp_lib_hash,
|
|
.unhash = udp_lib_unhash,
|
|
.get_port = udp_v4_get_port,
|
|
.memory_allocated = &udp_memory_allocated,
|
|
.sysctl_mem = sysctl_udp_mem,
|
|
.sysctl_wmem = &sysctl_udp_wmem_min,
|
|
.sysctl_rmem = &sysctl_udp_rmem_min,
|
|
.obj_size = sizeof(struct udp_sock),
|
|
.h.udp_hash = udp_hash,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_setsockopt = compat_udp_setsockopt,
|
|
.compat_getsockopt = compat_udp_getsockopt,
|
|
#endif
|
|
REF_PROTO_INUSE(udp)
|
|
};
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
#ifdef CONFIG_PROC_FS
|
|
|
|
static struct sock *udp_get_first(struct seq_file *seq)
|
|
{
|
|
struct sock *sk;
|
|
struct udp_iter_state *state = seq->private;
|
|
struct net *net = state->net;
|
|
|
|
for (state->bucket = 0; state->bucket < UDP_HTABLE_SIZE; ++state->bucket) {
|
|
struct hlist_node *node;
|
|
sk_for_each(sk, node, state->hashtable + state->bucket) {
|
|
if (sk->sk_net != net)
|
|
continue;
|
|
if (sk->sk_family == state->family)
|
|
goto found;
|
|
}
|
|
}
|
|
sk = NULL;
|
|
found:
|
|
return sk;
|
|
}
|
|
|
|
static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
|
|
{
|
|
struct udp_iter_state *state = seq->private;
|
|
struct net *net = state->net;
|
|
|
|
do {
|
|
sk = sk_next(sk);
|
|
try_again:
|
|
;
|
|
} while (sk && (sk->sk_net != net || sk->sk_family != state->family));
|
|
|
|
if (!sk && ++state->bucket < UDP_HTABLE_SIZE) {
|
|
sk = sk_head(state->hashtable + state->bucket);
|
|
goto try_again;
|
|
}
|
|
return sk;
|
|
}
|
|
|
|
static struct sock *udp_get_idx(struct seq_file *seq, loff_t pos)
|
|
{
|
|
struct sock *sk = udp_get_first(seq);
|
|
|
|
if (sk)
|
|
while (pos && (sk = udp_get_next(seq, sk)) != NULL)
|
|
--pos;
|
|
return pos ? NULL : sk;
|
|
}
|
|
|
|
static void *udp_seq_start(struct seq_file *seq, loff_t *pos)
|
|
__acquires(udp_hash_lock)
|
|
{
|
|
read_lock(&udp_hash_lock);
|
|
return *pos ? udp_get_idx(seq, *pos-1) : (void *)1;
|
|
}
|
|
|
|
static void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
{
|
|
struct sock *sk;
|
|
|
|
if (v == (void *)1)
|
|
sk = udp_get_idx(seq, 0);
|
|
else
|
|
sk = udp_get_next(seq, v);
|
|
|
|
++*pos;
|
|
return sk;
|
|
}
|
|
|
|
static void udp_seq_stop(struct seq_file *seq, void *v)
|
|
__releases(udp_hash_lock)
|
|
{
|
|
read_unlock(&udp_hash_lock);
|
|
}
|
|
|
|
static int udp_seq_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct udp_seq_afinfo *afinfo = PDE(inode)->data;
|
|
struct seq_file *seq;
|
|
struct net *net;
|
|
int rc = -ENOMEM;
|
|
struct udp_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
|
|
|
|
if (!s)
|
|
goto out;
|
|
|
|
rc = -ENXIO;
|
|
net = get_proc_net(inode);
|
|
if (!net)
|
|
goto out_kfree;
|
|
|
|
s->family = afinfo->family;
|
|
s->hashtable = afinfo->hashtable;
|
|
s->seq_ops.start = udp_seq_start;
|
|
s->seq_ops.next = udp_seq_next;
|
|
s->seq_ops.show = afinfo->seq_show;
|
|
s->seq_ops.stop = udp_seq_stop;
|
|
s->net = net;
|
|
|
|
rc = seq_open(file, &s->seq_ops);
|
|
if (rc)
|
|
goto out_put_net;
|
|
|
|
seq = file->private_data;
|
|
seq->private = s;
|
|
out:
|
|
return rc;
|
|
out_put_net:
|
|
put_net(net);
|
|
out_kfree:
|
|
kfree(s);
|
|
goto out;
|
|
}
|
|
|
|
static int udp_seq_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct seq_file *seq = file->private_data;
|
|
struct udp_iter_state *s = seq->private;
|
|
|
|
put_net(s->net);
|
|
seq_release_private(inode, file);
|
|
return 0;
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo)
|
|
{
|
|
struct proc_dir_entry *p;
|
|
int rc = 0;
|
|
|
|
if (!afinfo)
|
|
return -EINVAL;
|
|
afinfo->seq_fops->owner = afinfo->owner;
|
|
afinfo->seq_fops->open = udp_seq_open;
|
|
afinfo->seq_fops->read = seq_read;
|
|
afinfo->seq_fops->llseek = seq_lseek;
|
|
afinfo->seq_fops->release = udp_seq_release;
|
|
|
|
p = proc_net_fops_create(net, afinfo->name, S_IRUGO, afinfo->seq_fops);
|
|
if (p)
|
|
p->data = afinfo;
|
|
else
|
|
rc = -ENOMEM;
|
|
return rc;
|
|
}
|
|
|
|
void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo)
|
|
{
|
|
if (!afinfo)
|
|
return;
|
|
proc_net_remove(net, afinfo->name);
|
|
memset(afinfo->seq_fops, 0, sizeof(*afinfo->seq_fops));
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
static void udp4_format_sock(struct sock *sp, char *tmpbuf, int bucket)
|
|
{
|
|
struct inet_sock *inet = inet_sk(sp);
|
|
__be32 dest = inet->daddr;
|
|
__be32 src = inet->rcv_saddr;
|
|
__u16 destp = ntohs(inet->dport);
|
|
__u16 srcp = ntohs(inet->sport);
|
|
|
|
sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X"
|
|
" %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p",
|
|
bucket, src, srcp, dest, destp, sp->sk_state,
|
|
atomic_read(&sp->sk_wmem_alloc),
|
|
atomic_read(&sp->sk_rmem_alloc),
|
|
0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
|
|
atomic_read(&sp->sk_refcnt), sp);
|
|
}
|
|
|
|
int udp4_seq_show(struct seq_file *seq, void *v)
|
|
{
|
|
if (v == SEQ_START_TOKEN)
|
|
seq_printf(seq, "%-127s\n",
|
|
" sl local_address rem_address st tx_queue "
|
|
"rx_queue tr tm->when retrnsmt uid timeout "
|
|
"inode");
|
|
else {
|
|
char tmpbuf[129];
|
|
struct udp_iter_state *state = seq->private;
|
|
|
|
udp4_format_sock(v, tmpbuf, state->bucket);
|
|
seq_printf(seq, "%-127s\n", tmpbuf);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
static struct file_operations udp4_seq_fops;
|
|
static struct udp_seq_afinfo udp4_seq_afinfo = {
|
|
.owner = THIS_MODULE,
|
|
.name = "udp",
|
|
.family = AF_INET,
|
|
.hashtable = udp_hash,
|
|
.seq_show = udp4_seq_show,
|
|
.seq_fops = &udp4_seq_fops,
|
|
};
|
|
|
|
static int udp4_proc_init_net(struct net *net)
|
|
{
|
|
return udp_proc_register(net, &udp4_seq_afinfo);
|
|
}
|
|
|
|
static void udp4_proc_exit_net(struct net *net)
|
|
{
|
|
udp_proc_unregister(net, &udp4_seq_afinfo);
|
|
}
|
|
|
|
static struct pernet_operations udp4_net_ops = {
|
|
.init = udp4_proc_init_net,
|
|
.exit = udp4_proc_exit_net,
|
|
};
|
|
|
|
int __init udp4_proc_init(void)
|
|
{
|
|
return register_pernet_subsys(&udp4_net_ops);
|
|
}
|
|
|
|
void udp4_proc_exit(void)
|
|
{
|
|
unregister_pernet_subsys(&udp4_net_ops);
|
|
}
|
|
#endif /* CONFIG_PROC_FS */
|
|
|
|
void __init udp_init(void)
|
|
{
|
|
unsigned long limit;
|
|
|
|
/* Set the pressure threshold up by the same strategy of TCP. It is a
|
|
* fraction of global memory that is up to 1/2 at 256 MB, decreasing
|
|
* toward zero with the amount of memory, with a floor of 128 pages.
|
|
*/
|
|
limit = min(nr_all_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
|
|
limit = (limit * (nr_all_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
|
|
limit = max(limit, 128UL);
|
|
sysctl_udp_mem[0] = limit / 4 * 3;
|
|
sysctl_udp_mem[1] = limit;
|
|
sysctl_udp_mem[2] = sysctl_udp_mem[0] * 2;
|
|
|
|
sysctl_udp_rmem_min = SK_MEM_QUANTUM;
|
|
sysctl_udp_wmem_min = SK_MEM_QUANTUM;
|
|
}
|
|
|
|
EXPORT_SYMBOL(udp_disconnect);
|
|
EXPORT_SYMBOL(udp_hash);
|
|
EXPORT_SYMBOL(udp_hash_lock);
|
|
EXPORT_SYMBOL(udp_ioctl);
|
|
EXPORT_SYMBOL(udp_prot);
|
|
EXPORT_SYMBOL(udp_sendmsg);
|
|
EXPORT_SYMBOL(udp_lib_getsockopt);
|
|
EXPORT_SYMBOL(udp_lib_setsockopt);
|
|
EXPORT_SYMBOL(udp_poll);
|
|
EXPORT_SYMBOL(udp_lib_get_port);
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
EXPORT_SYMBOL(udp_proc_register);
|
|
EXPORT_SYMBOL(udp_proc_unregister);
|
|
#endif
|