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/*
* 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.
*
* Generic socket support routines. Memory allocators, socket lock/release
* handler for protocols to use and generic option handler.
*
*
* Version: $Id: sock.c,v 1.116 2001/11/08 04:20:06 davem Exp $
*
* Authors: Ross Biro, <bir7@leland.Stanford.Edu>
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Florian La Roche, <flla@stud.uni-sb.de>
* Alan Cox, <A.Cox@swansea.ac.uk>
*
* Fixes:
* Alan Cox : Numerous verify_area() problems
* Alan Cox : Connecting on a connecting socket
* now returns an error for tcp.
* Alan Cox : sock->protocol is set correctly.
* and is not sometimes left as 0.
* Alan Cox : connect handles icmp errors on a
* connect properly. Unfortunately there
* is a restart syscall nasty there. I
* can't match BSD without hacking the C
* library. Ideas urgently sought!
* Alan Cox : Disallow bind() to addresses that are
* not ours - especially broadcast ones!!
* Alan Cox : Socket 1024 _IS_ ok for users. (fencepost)
* Alan Cox : sock_wfree/sock_rfree don't destroy sockets,
* instead they leave that for the DESTROY timer.
* Alan Cox : Clean up error flag in accept
* Alan Cox : TCP ack handling is buggy, the DESTROY timer
* was buggy. Put a remove_sock() in the handler
* for memory when we hit 0. Also altered the timer
* code. The ACK stuff can wait and needs major
* TCP layer surgery.
* Alan Cox : Fixed TCP ack bug, removed remove sock
* and fixed timer/inet_bh race.
* Alan Cox : Added zapped flag for TCP
* Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code
* Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
* Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources
* Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing.
* Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
* Rick Sladkey : Relaxed UDP rules for matching packets.
* C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support
* Pauline Middelink : identd support
* Alan Cox : Fixed connect() taking signals I think.
* Alan Cox : SO_LINGER supported
* Alan Cox : Error reporting fixes
* Anonymous : inet_create tidied up (sk->reuse setting)
* Alan Cox : inet sockets don't set sk->type!
* Alan Cox : Split socket option code
* Alan Cox : Callbacks
* Alan Cox : Nagle flag for Charles & Johannes stuff
* Alex : Removed restriction on inet fioctl
* Alan Cox : Splitting INET from NET core
* Alan Cox : Fixed bogus SO_TYPE handling in getsockopt()
* Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code
* Alan Cox : Split IP from generic code
* Alan Cox : New kfree_skbmem()
* Alan Cox : Make SO_DEBUG superuser only.
* Alan Cox : Allow anyone to clear SO_DEBUG
* (compatibility fix)
* Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput.
* Alan Cox : Allocator for a socket is settable.
* Alan Cox : SO_ERROR includes soft errors.
* Alan Cox : Allow NULL arguments on some SO_ opts
* Alan Cox : Generic socket allocation to make hooks
* easier (suggested by Craig Metz).
* Michael Pall : SO_ERROR returns positive errno again
* Steve Whitehouse: Added default destructor to free
* protocol private data.
* Steve Whitehouse: Added various other default routines
* common to several socket families.
* Chris Evans : Call suser() check last on F_SETOWN
* Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
* Andi Kleen : Add sock_kmalloc()/sock_kfree_s()
* Andi Kleen : Fix write_space callback
* Chris Evans : Security fixes - signedness again
* Arnaldo C. Melo : cleanups, use skb_queue_purge
*
* To Fix:
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/config.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/netdevice.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/ipsec.h>
#ifdef CONFIG_FILTER
#include <linux/filter.h>
#endif
#ifdef CONFIG_INET
#include <net/tcp.h>
#endif
/* Run time adjustable parameters. */
__u32 sysctl_wmem_max = SK_WMEM_MAX;
__u32 sysctl_rmem_max = SK_RMEM_MAX;
__u32 sysctl_wmem_default = SK_WMEM_MAX;
__u32 sysctl_rmem_default = SK_RMEM_MAX;
/* Maximal space eaten by iovec or ancilliary data plus some space */
int sysctl_optmem_max = sizeof(unsigned long)*(2*UIO_MAXIOV + 512);
static int sock_set_timeout(long *timeo_p, char *optval, int optlen)
{
struct timeval tv;
if (optlen < sizeof(tv))
return -EINVAL;
if (copy_from_user(&tv, optval, sizeof(tv)))
return -EFAULT;
*timeo_p = MAX_SCHEDULE_TIMEOUT;
if (tv.tv_sec == 0 && tv.tv_usec == 0)
return 0;
if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
return 0;
}
/*
* This is meant for all protocols to use and covers goings on
* at the socket level. Everything here is generic.
*/
int sock_setsockopt(struct socket *sock, int level, int optname,
char *optval, int optlen)
{
struct sock *sk=sock->sk;
#ifdef CONFIG_FILTER
struct sk_filter *filter;
#endif
int val;
int valbool;
struct linger ling;
int ret = 0;
/*
* Options without arguments
*/
#ifdef SO_DONTLINGER /* Compatibility item... */
switch(optname)
{
case SO_DONTLINGER:
sk->linger=0;
return 0;
}
#endif
if(optlen<sizeof(int))
return(-EINVAL);
if (get_user(val, (int *)optval))
return -EFAULT;
valbool = val?1:0;
lock_sock(sk);
switch(optname)
{
case SO_DEBUG:
if(val && !capable(CAP_NET_ADMIN))
{
ret = -EACCES;
}
else
sk->debug=valbool;
break;
case SO_REUSEADDR:
sk->reuse = valbool;
break;
case SO_TYPE:
case SO_ERROR:
ret = -ENOPROTOOPT;
break;
case SO_DONTROUTE:
sk->localroute=valbool;
break;
case SO_BROADCAST:
sk->broadcast=valbool;
break;
case SO_SNDBUF:
/* Don't error on this BSD doesn't and if you think
about it this is right. Otherwise apps have to
play 'guess the biggest size' games. RCVBUF/SNDBUF
are treated in BSD as hints */
if (val > sysctl_wmem_max)
val = sysctl_wmem_max;
sk->userlocks |= SOCK_SNDBUF_LOCK;
if ((val * 2) < SOCK_MIN_SNDBUF)
sk->sndbuf = SOCK_MIN_SNDBUF;
else
sk->sndbuf = (val * 2);
/*
* Wake up sending tasks if we
* upped the value.
*/
sk->write_space(sk);
break;
case SO_RCVBUF:
/* Don't error on this BSD doesn't and if you think
about it this is right. Otherwise apps have to
play 'guess the biggest size' games. RCVBUF/SNDBUF
are treated in BSD as hints */
if (val > sysctl_rmem_max)
val = sysctl_rmem_max;
sk->userlocks |= SOCK_RCVBUF_LOCK;
/* FIXME: is this lower bound the right one? */
if ((val * 2) < SOCK_MIN_RCVBUF)
sk->rcvbuf = SOCK_MIN_RCVBUF;
else
sk->rcvbuf = (val * 2);
break;
case SO_KEEPALIVE:
#ifdef CONFIG_INET
if (sk->protocol == IPPROTO_TCP)
{
tcp_set_keepalive(sk, valbool);
}
#endif
sk->keepopen = valbool;
break;
case SO_OOBINLINE:
sk->urginline = valbool;
break;
case SO_NO_CHECK:
sk->no_check = valbool;
break;
case SO_PRIORITY:
if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
sk->priority = val;
else
ret = -EPERM;
break;
case SO_LINGER:
if(optlen<sizeof(ling)) {
ret = -EINVAL; /* 1003.1g */
break;
}
if (copy_from_user(&ling,optval,sizeof(ling))) {
ret = -EFAULT;
break;
}
if(ling.l_onoff==0) {
sk->linger=0;
} else {
#if (BITS_PER_LONG == 32)
if (ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
sk->lingertime=MAX_SCHEDULE_TIMEOUT;
else
#endif
sk->lingertime=ling.l_linger*HZ;
sk->linger=1;
}
break;
case SO_BSDCOMPAT:
sk->bsdism = valbool;
break;
case SO_PASSCRED:
sock->passcred = valbool;
break;
case SO_TIMESTAMP:
sk->rcvtstamp = valbool;
break;
case SO_RCVLOWAT:
if (val < 0)
val = INT_MAX;
sk->rcvlowat = val ? : 1;
break;
case SO_RCVTIMEO:
ret = sock_set_timeout(&sk->rcvtimeo, optval, optlen);
break;
case SO_SNDTIMEO:
ret = sock_set_timeout(&sk->sndtimeo, optval, optlen);
break;
#ifdef CONFIG_NETDEVICES
case SO_BINDTODEVICE:
{
char devname[IFNAMSIZ];
/* Sorry... */
if (!capable(CAP_NET_RAW)) {
ret = -EPERM;
break;
}
/* Bind this socket to a particular device like "eth0",
* as specified in the passed interface name. If the
* name is "" or the option length is zero the socket
* is not bound.
*/
if (!valbool) {
sk->bound_dev_if = 0;
} else {
if (optlen > IFNAMSIZ)
optlen = IFNAMSIZ;
if (copy_from_user(devname, optval, optlen)) {
ret = -EFAULT;
break;
}
/* Remove any cached route for this socket. */
sk_dst_reset(sk);
if (devname[0] == '\0') {
sk->bound_dev_if = 0;
} else {
struct net_device *dev = dev_get_by_name(devname);
if (!dev) {
ret = -ENODEV;
break;
}
sk->bound_dev_if = dev->ifindex;
dev_put(dev);
}
}
break;
}
#endif
#ifdef CONFIG_FILTER
case SO_ATTACH_FILTER:
ret = -EINVAL;
if (optlen == sizeof(struct sock_fprog)) {
struct sock_fprog fprog;
ret = -EFAULT;
if (copy_from_user(&fprog, optval, sizeof(fprog)))
break;
ret = sk_attach_filter(&fprog, sk);
}
break;
case SO_DETACH_FILTER:
spin_lock_bh(&sk->lock.slock);
filter = sk->filter;
if (filter) {
sk->filter = NULL;
spin_unlock_bh(&sk->lock.slock);
sk_filter_release(sk, filter);
break;
}
spin_unlock_bh(&sk->lock.slock);
ret = -ENONET;
break;
#endif
/* We implement the SO_SNDLOWAT etc to
not be settable (1003.1g 5.3) */
default:
ret = -ENOPROTOOPT;
break;
}
release_sock(sk);
return ret;
}
int sock_getsockopt(struct socket *sock, int level, int optname,
char *optval, int *optlen)
{
struct sock *sk = sock->sk;
union
{
int val;
struct linger ling;
struct timeval tm;
} v;
unsigned int lv=sizeof(int),len;
if(get_user(len,optlen))
return -EFAULT;
if(len < 0)
return -EINVAL;
switch(optname)
{
case SO_DEBUG:
v.val = sk->debug;
break;
case SO_DONTROUTE:
v.val = sk->localroute;
break;
case SO_BROADCAST:
v.val= sk->broadcast;
break;
case SO_SNDBUF:
v.val=sk->sndbuf;
break;
case SO_RCVBUF:
v.val =sk->rcvbuf;
break;
case SO_REUSEADDR:
v.val = sk->reuse;
break;
case SO_KEEPALIVE:
v.val = sk->keepopen;
break;
case SO_TYPE:
v.val = sk->type;
break;
case SO_ERROR:
v.val = -sock_error(sk);
if(v.val==0)
v.val=xchg(&sk->err_soft,0);
break;
case SO_OOBINLINE:
v.val = sk->urginline;
break;
case SO_NO_CHECK:
v.val = sk->no_check;
break;
case SO_PRIORITY:
v.val = sk->priority;
break;
case SO_LINGER:
lv=sizeof(v.ling);
v.ling.l_onoff=sk->linger;
v.ling.l_linger=sk->lingertime/HZ;
break;
case SO_BSDCOMPAT:
v.val = sk->bsdism;
break;
case SO_TIMESTAMP:
v.val = sk->rcvtstamp;
break;
case SO_RCVTIMEO:
lv=sizeof(struct timeval);
if (sk->rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
v.tm.tv_sec = 0;
v.tm.tv_usec = 0;
} else {
v.tm.tv_sec = sk->rcvtimeo/HZ;
v.tm.tv_usec = ((sk->rcvtimeo%HZ)*1000)/HZ;
}
break;
case SO_SNDTIMEO:
lv=sizeof(struct timeval);
if (sk->sndtimeo == MAX_SCHEDULE_TIMEOUT) {
v.tm.tv_sec = 0;
v.tm.tv_usec = 0;
} else {
v.tm.tv_sec = sk->sndtimeo/HZ;
v.tm.tv_usec = ((sk->sndtimeo%HZ)*1000)/HZ;
}
break;
case SO_RCVLOWAT:
v.val = sk->rcvlowat;
break;
case SO_SNDLOWAT:
v.val=1;
break;
case SO_PASSCRED:
v.val = sock->passcred;
break;
case SO_PEERCRED:
if (len > sizeof(sk->peercred))
len = sizeof(sk->peercred);
if (copy_to_user(optval, &sk->peercred, len))
return -EFAULT;
goto lenout;
case SO_PEERNAME:
{
char address[128];
if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
return -ENOTCONN;
if (lv < len)
return -EINVAL;
if(copy_to_user((void*)optval, address, len))
return -EFAULT;
goto lenout;
}
/* Dubious BSD thing... Probably nobody even uses it, but
* the UNIX standard wants it for whatever reason... -DaveM
*/
case SO_ACCEPTCONN:
v.val = (sk->state == TCP_LISTEN);
break;
default:
return(-ENOPROTOOPT);
}
if (len > lv)
len = lv;
if (copy_to_user(optval, &v, len))
return -EFAULT;
lenout:
if (put_user(len, optlen))
return -EFAULT;
return 0;
}
static kmem_cache_t *sk_cachep;
/*
* All socket objects are allocated here. This is for future
* usage.
*/
struct sock *sk_alloc(int family, int priority, int zero_it)
{
struct sock *sk = kmem_cache_alloc(sk_cachep, priority);
if(sk && zero_it) {
memset(sk, 0, sizeof(struct sock));
sk->family = family;
sock_lock_init(sk);
}
return sk;
}
void sk_free(struct sock *sk)
{
#ifdef CONFIG_FILTER
struct sk_filter *filter;
#endif
if (sk->destruct)
sk->destruct(sk);
#ifdef CONFIG_FILTER
filter = sk->filter;
if (filter) {
sk_filter_release(sk, filter);
sk->filter = NULL;
}
#endif
if (atomic_read(&sk->omem_alloc))
printk(KERN_DEBUG "sk_free: optmem leakage (%d bytes) detected.\n", atomic_read(&sk->omem_alloc));
kmem_cache_free(sk_cachep, sk);
}
void __init sk_init(void)
{
sk_cachep = kmem_cache_create("sock", sizeof(struct sock), 0,
SLAB_HWCACHE_ALIGN, 0, 0);
if (!sk_cachep)
printk(KERN_CRIT "sk_init: Cannot create sock SLAB cache!");
if (num_physpages <= 4096) {
sysctl_wmem_max = 32767;
sysctl_rmem_max = 32767;
sysctl_wmem_default = 32767;
sysctl_wmem_default = 32767;
} else if (num_physpages >= 131072) {
sysctl_wmem_max = 131071;
sysctl_rmem_max = 131071;
}
}
/*
* Simple resource managers for sockets.
*/
/*
* Write buffer destructor automatically called from kfree_skb.
*/
void sock_wfree(struct sk_buff *skb)
{
struct sock *sk = skb->sk;
/* In case it might be waiting for more memory. */
atomic_sub(skb->truesize, &sk->wmem_alloc);
if (!sk->use_write_queue)
sk->write_space(sk);
sock_put(sk);
}
/*
* Read buffer destructor automatically called from kfree_skb.
*/
void sock_rfree(struct sk_buff *skb)
{
struct sock *sk = skb->sk;
atomic_sub(skb->truesize, &sk->rmem_alloc);
}
/*
* Allocate a skb from the socket's send buffer.
*/
struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, int priority)
{
if (force || atomic_read(&sk->wmem_alloc) < sk->sndbuf) {
struct sk_buff * skb = alloc_skb(size, priority);
if (skb) {
skb_set_owner_w(skb, sk);
return skb;
}
}
return NULL;
}
/*
* Allocate a skb from the socket's receive buffer.
*/
struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, int priority)
{
if (force || atomic_read(&sk->rmem_alloc) < sk->rcvbuf) {
struct sk_buff *skb = alloc_skb(size, priority);
if (skb) {
skb_set_owner_r(skb, sk);
return skb;
}
}
return NULL;
}
/*
* Allocate a memory block from the socket's option memory buffer.
*/
void *sock_kmalloc(struct sock *sk, int size, int priority)
{
if ((unsigned)size <= sysctl_optmem_max &&
atomic_read(&sk->omem_alloc)+size < sysctl_optmem_max) {
void *mem;
/* First do the add, to avoid the race if kmalloc
* might sleep.
*/
atomic_add(size, &sk->omem_alloc);
mem = kmalloc(size, priority);
if (mem)
return mem;
atomic_sub(size, &sk->omem_alloc);
}
return NULL;
}
/*
* Free an option memory block.
*/
void sock_kfree_s(struct sock *sk, void *mem, int size)
{
kfree(mem);
atomic_sub(size, &sk->omem_alloc);
}
/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
I think, these locks should be removed for datagram sockets.
*/
static long sock_wait_for_wmem(struct sock * sk, long timeo)
{
DECLARE_WAITQUEUE(wait, current);
clear_bit(SOCK_ASYNC_NOSPACE, &sk->socket->flags);
add_wait_queue(sk->sleep, &wait);
for (;;) {
if (!timeo)
break;
if (signal_pending(current))
break;
set_bit(SOCK_NOSPACE, &sk->socket->flags);
set_current_state(TASK_INTERRUPTIBLE);
if (atomic_read(&sk->wmem_alloc) < sk->sndbuf)
break;
if (sk->shutdown & SEND_SHUTDOWN)
break;
if (sk->err)
break;
timeo = schedule_timeout(timeo);
}
__set_current_state(TASK_RUNNING);
remove_wait_queue(sk->sleep, &wait);
return timeo;
}
/*
* Generic send/receive buffer handlers
*/
struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
unsigned long data_len, int noblock, int *errcode)
{
struct sk_buff *skb;
long timeo;
int err;
timeo = sock_sndtimeo(sk, noblock);
while (1) {
err = sock_error(sk);
if (err != 0)
goto failure;
err = -EPIPE;
if (sk->shutdown & SEND_SHUTDOWN)
goto failure;
if (atomic_read(&sk->wmem_alloc) < sk->sndbuf) {
skb = alloc_skb(header_len, sk->allocation);
if (skb) {
int npages;
int i;
/* No pages, we're done... */
if (!data_len)
break;
npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
skb->truesize += data_len;
skb_shinfo(skb)->nr_frags = npages;
for (i = 0; i < npages; i++) {
struct page *page;
skb_frag_t *frag;
page = alloc_pages(sk->allocation, 0);
if (!page) {
err = -ENOBUFS;
kfree_skb(skb);
goto failure;
}
frag = &skb_shinfo(skb)->frags[i];
frag->page = page;
frag->page_offset = 0;
frag->size = (data_len >= PAGE_SIZE ?
PAGE_SIZE :
data_len);
data_len -= PAGE_SIZE;
}
/* Full success... */
break;
}
err = -ENOBUFS;
goto failure;
}
set_bit(SOCK_ASYNC_NOSPACE, &sk->socket->flags);
set_bit(SOCK_NOSPACE, &sk->socket->flags);
err = -EAGAIN;
if (!timeo)
goto failure;
if (signal_pending(current))
goto interrupted;
timeo = sock_wait_for_wmem(sk, timeo);
}
skb_set_owner_w(skb, sk);
return skb;
interrupted:
err = sock_intr_errno(timeo);
failure:
*errcode = err;
return NULL;
}
struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
int noblock, int *errcode)
{
return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
}
void __lock_sock(struct sock *sk)
{
DECLARE_WAITQUEUE(wait, current);
add_wait_queue_exclusive(&sk->lock.wq, &wait);
for(;;) {
current->state = TASK_UNINTERRUPTIBLE;
spin_unlock_bh(&sk->lock.slock);
schedule();
spin_lock_bh(&sk->lock.slock);
if(!sk->lock.users)
break;
}
current->state = TASK_RUNNING;
remove_wait_queue(&sk->lock.wq, &wait);
}
void __release_sock(struct sock *sk)
{
struct sk_buff *skb = sk->backlog.head;
do {
sk->backlog.head = sk->backlog.tail = NULL;
bh_unlock_sock(sk);
do {
struct sk_buff *next = skb->next;
skb->next = NULL;
sk->backlog_rcv(sk, skb);
skb = next;
} while (skb != NULL);
bh_lock_sock(sk);
} while((skb = sk->backlog.head) != NULL);
}
/*
* Generic socket manager library. Most simpler socket families
* use this to manage their socket lists. At some point we should
* hash these. By making this generic we get the lot hashed for free.
*
* It is broken by design. All the protocols using it must be fixed. --ANK
*/
rwlock_t net_big_sklist_lock = RW_LOCK_UNLOCKED;
void sklist_remove_socket(struct sock **list, struct sock *sk)
{
struct sock *s;
write_lock_bh(&net_big_sklist_lock);
while ((s = *list) != NULL) {
if (s == sk) {
*list = s->next;
break;
}
list = &s->next;
}
write_unlock_bh(&net_big_sklist_lock);
if (s)
sock_put(s);
}
void sklist_insert_socket(struct sock **list, struct sock *sk)
{
write_lock_bh(&net_big_sklist_lock);
sk->next= *list;
*list=sk;
sock_hold(sk);
write_unlock_bh(&net_big_sklist_lock);
}
/*
* This is only called from user mode. Thus it protects itself against
* interrupt users but doesn't worry about being called during work.
* Once it is removed from the queue no interrupt or bottom half will
* touch it and we are (fairly 8-) ) safe.
*/
void sklist_destroy_socket(struct sock **list, struct sock *sk);
/*
* Handler for deferred kills.
*/
static void sklist_destroy_timer(unsigned long data)
{
struct sock *sk=(struct sock *)data;
sklist_destroy_socket(NULL,sk);
}
/*
* Destroy a socket. We pass NULL for a list if we know the
* socket is not on a list.
*/
void sklist_destroy_socket(struct sock **list,struct sock *sk)
{
if(list)
sklist_remove_socket(list, sk);
skb_queue_purge(&sk->receive_queue);
if(atomic_read(&sk->wmem_alloc) == 0 &&
atomic_read(&sk->rmem_alloc) == 0 &&
sk->dead)
{
sock_put(sk);
}
else
{
/*
* Someone is using our buffers still.. defer
*/
init_timer(&sk->timer);
sk->timer.expires=jiffies+SOCK_DESTROY_TIME;
sk->timer.function=sklist_destroy_timer;
sk->timer.data = (unsigned long)sk;
add_timer(&sk->timer);
}
}
/*
* Set of default routines for initialising struct proto_ops when
* the protocol does not support a particular function. In certain
* cases where it makes no sense for a protocol to have a "do nothing"
* function, some default processing is provided.
*/
int sock_no_release(struct socket *sock)
{
return 0;
}
int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
{
return -EOPNOTSUPP;
}
int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
int len, int flags)
{
return -EOPNOTSUPP;
}
int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
{
return -EOPNOTSUPP;
}
int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
{
return -EOPNOTSUPP;
}
int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
int *len, int peer)
{
return -EOPNOTSUPP;
}
unsigned int sock_no_poll(struct file * file, struct socket *sock, poll_table *pt)
{
return 0;
}
int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
return -EOPNOTSUPP;
}
int sock_no_listen(struct socket *sock, int backlog)
{
return -EOPNOTSUPP;
}
int sock_no_shutdown(struct socket *sock, int how)
{
return -EOPNOTSUPP;
}
int sock_no_setsockopt(struct socket *sock, int level, int optname,
char *optval, int optlen)
{
return -EOPNOTSUPP;
}
int sock_no_getsockopt(struct socket *sock, int level, int optname,
char *optval, int *optlen)
{
return -EOPNOTSUPP;
}
/*
* Note: if you add something that sleeps here then change sock_fcntl()
* to do proper fd locking.
*/
int sock_no_fcntl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
struct sock *sk = sock->sk;
switch(cmd)
{
case F_SETOWN:
/*
* This is a little restrictive, but it's the only
* way to make sure that you can't send a sigurg to
* another process.
*/
if (current->pgrp != -arg &&
current->pid != arg &&
!capable(CAP_KILL)) return(-EPERM);
sk->proc = arg;
return(0);
case F_GETOWN:
return(sk->proc);
default:
return(-EINVAL);
}
}
int sock_no_sendmsg(struct socket *sock, struct msghdr *m, int flags,
struct scm_cookie *scm)
{
return -EOPNOTSUPP;
}
int sock_no_recvmsg(struct socket *sock, struct msghdr *m, int len, int flags,
struct scm_cookie *scm)
{
return -EOPNOTSUPP;
}
int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
{
/* Mirror missing mmap method error code */
return -ENODEV;
}
ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
{
ssize_t res;
struct msghdr msg;
struct iovec iov;
mm_segment_t old_fs;
char *kaddr;
kaddr = kmap(page);
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = flags;
iov.iov_base = kaddr + offset;
iov.iov_len = size;
old_fs = get_fs();
set_fs(KERNEL_DS);
res = sock_sendmsg(sock, &msg, size);
set_fs(old_fs);
kunmap(page);
return res;
}
/*
* Default Socket Callbacks
*/
void sock_def_wakeup(struct sock *sk)
{
read_lock(&sk->callback_lock);
if (sk->sleep && waitqueue_active(sk->sleep))
wake_up_interruptible_all(sk->sleep);
read_unlock(&sk->callback_lock);
}
void sock_def_error_report(struct sock *sk)
{
read_lock(&sk->callback_lock);
if (sk->sleep && waitqueue_active(sk->sleep))
wake_up_interruptible(sk->sleep);
sk_wake_async(sk,0,POLL_ERR);
read_unlock(&sk->callback_lock);
}
void sock_def_readable(struct sock *sk, int len)
{
read_lock(&sk->callback_lock);
if (sk->sleep && waitqueue_active(sk->sleep))
wake_up_interruptible(sk->sleep);
sk_wake_async(sk,1,POLL_IN);
read_unlock(&sk->callback_lock);
}
void sock_def_write_space(struct sock *sk)
{
read_lock(&sk->callback_lock);
/* Do not wake up a writer until he can make "significant"
* progress. --DaveM
*/
if((atomic_read(&sk->wmem_alloc) << 1) <= sk->sndbuf) {
if (sk->sleep && waitqueue_active(sk->sleep))
wake_up_interruptible(sk->sleep);
/* Should agree with poll, otherwise some programs break */
if (sock_writeable(sk))
sk_wake_async(sk, 2, POLL_OUT);
}
read_unlock(&sk->callback_lock);
}
void sock_def_destruct(struct sock *sk)
{
if (sk->protinfo.destruct_hook)
kfree(sk->protinfo.destruct_hook);
}
void sock_init_data(struct socket *sock, struct sock *sk)
{
skb_queue_head_init(&sk->receive_queue);
skb_queue_head_init(&sk->write_queue);
skb_queue_head_init(&sk->error_queue);
init_timer(&sk->timer);
sk->allocation = GFP_KERNEL;
sk->rcvbuf = sysctl_rmem_default;
sk->sndbuf = sysctl_wmem_default;
sk->state = TCP_CLOSE;
sk->zapped = 1;
sk->socket = sock;
if(sock)
{
sk->type = sock->type;
sk->sleep = &sock->wait;
sock->sk = sk;
} else
sk->sleep = NULL;
sk->dst_lock = RW_LOCK_UNLOCKED;
sk->callback_lock = RW_LOCK_UNLOCKED;
sk->state_change = sock_def_wakeup;
sk->data_ready = sock_def_readable;
sk->write_space = sock_def_write_space;
sk->error_report = sock_def_error_report;
sk->destruct = sock_def_destruct;
sk->peercred.pid = 0;
sk->peercred.uid = -1;
sk->peercred.gid = -1;
sk->rcvlowat = 1;
sk->rcvtimeo = MAX_SCHEDULE_TIMEOUT;
sk->sndtimeo = MAX_SCHEDULE_TIMEOUT;
atomic_set(&sk->refcnt, 1);
}
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