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af_wanpipe.c
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/*****************************************************************************
* af_wanpipe.c WANPIPE(tm) Secure Socket Layer.
*
* Author: Nenad Corbic <ncorbic@sangoma.com>
*
* Copyright: (c) 2000 Sangoma Technologies Inc.
*
* 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.
* ============================================================================
* Due Credit:
* Wanpipe socket layer is based on Packet and
* the X25 socket layers. The above sockets were
* used for the specific use of Sangoma Technoloiges
* API programs.
* Packet socket Authors: Ross Biro, Fred N. van Kempen and
* Alan Cox.
* X25 socket Author: Jonathan Naylor.
* ============================================================================
* Mar 15, 2002 Arnaldo C. Melo o Use wp_sk()->num, as it isnt anymore in sock
* Apr 25, 2000 Nenad Corbic o Added the ability to send zero length packets.
* Mar 13, 2000 Nenad Corbic o Added a tx buffer check via ioctl call.
* Mar 06, 2000 Nenad Corbic o Fixed the corrupt sock lcn problem.
* Server and client applicaton can run
* simultaneously without conflicts.
* Feb 29, 2000 Nenad Corbic o Added support for PVC protocols, such as
* CHDLC, Frame Relay and HDLC API.
* Jan 17, 2000 Nenad Corbic o Initial version, based on AF_PACKET socket.
* X25API support only.
*
******************************************************************************/
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/capability.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/poll.h>
#include <linux/wireless.h>
#include <linux/kmod.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/if_wanpipe.h>
#include <linux/pkt_sched.h>
#include <linux/tcp_states.h>
#include <linux/if_wanpipe_common.h>
#ifdef CONFIG_INET
#include <net/inet_common.h>
#endif
#define SLOW_BACKOFF 0.1*HZ
#define FAST_BACKOFF 0.01*HZ
//#define PRINT_DEBUG
#ifdef PRINT_DEBUG
#define DBG_PRINTK(format, a...) printk(format, ## a)
#else
#define DBG_PRINTK(format, a...)
#endif
/* SECURE SOCKET IMPLEMENTATION
*
* TRANSMIT:
*
* When the user sends a packet via send() system call
* the wanpipe_sendmsg() function is executed.
*
* Each packet is enqueud into sk->sk_write_queue transmit
* queue. When the packet is enqueued, a delayed transmit
* timer is triggerd which acts as a Bottom Half hander.
*
* wanpipe_delay_transmit() function (BH), dequeues packets
* from the sk->sk_write_queue transmit queue and sends it
* to the deriver via dev->hard_start_xmit(skb, dev) function.
* Note, this function is actual a function pointer of if_send()
* routine in the wanpipe driver.
*
* X25API GUARANTEED DELIVERY:
*
* In order to provide 100% guaranteed packet delivery,
* an atomic 'packet_sent' counter is implemented. Counter
* is incremented for each packet enqueued
* into sk->sk_write_queue. Counter is decremented each
* time wanpipe_delayed_transmit() function successfuly
* passes the packet to the driver. Before each send(), a poll
* routine checks the sock resources The maximum value of
* packet sent counter is 1, thus if one packet is queued, the
* application will block until that packet is passed to the
* driver.
*
* RECEIVE:
*
* Wanpipe device drivers call the socket bottom half
* function, wanpipe_rcv() to queue the incoming packets
* into an AF_WANPIPE socket queue. Based on wanpipe_rcv()
* return code, the driver knows whether the packet was
* successfully queued. If the socket queue is full,
* protocol flow control is used by the driver, if any,
* to slow down the traffic until the sock queue is free.
*
* Every time a packet arrives into a socket queue the
* socket wakes up processes which are waiting to receive
* data.
*
* If the socket queue is full, the driver sets a block
* bit which signals the socket to kick the wanpipe driver
* bottom half hander when the socket queue is partialy
* empty. wanpipe_recvmsg() function performs this action.
*
* In case of x25api, packets will never be dropped, since
* flow control is available.
*
* In case of streaming protocols like CHDLC, packets will
* be dropped but the statistics will be generated.
*/
/* The code below is used to test memory leaks. It prints out
* a message every time kmalloc and kfree system calls get executed.
* If the calls match there is no leak :)
*/
/***********FOR DEBUGGING PURPOSES*********************************************
#define KMEM_SAFETYZONE 8
static void * dbg_kmalloc(unsigned int size, int prio, int line) {
void * v = kmalloc(size,prio);
printk(KERN_INFO "line %d kmalloc(%d,%d) = %p\n",line,size,prio,v);
return v;
}
static void dbg_kfree(void * v, int line) {
printk(KERN_INFO "line %d kfree(%p)\n",line,v);
kfree(v);
}
#define kmalloc(x,y) dbg_kmalloc(x,y,__LINE__)
#define kfree(x) dbg_kfree(x,__LINE__)
******************************************************************************/
/* List of all wanpipe sockets. */
HLIST_HEAD(wanpipe_sklist);
static DEFINE_RWLOCK(wanpipe_sklist_lock);
atomic_t wanpipe_socks_nr;
static unsigned long wanpipe_tx_critical;
#if 0
/* Private wanpipe socket structures. */
struct wanpipe_opt
{
void *mbox; /* Mail box */
void *card; /* Card bouded to */
struct net_device *dev; /* Bounded device */
unsigned short lcn; /* Binded LCN */
unsigned char svc; /* 0=pvc, 1=svc */
unsigned char timer; /* flag for delayed transmit*/
struct timer_list tx_timer;
unsigned poll_cnt;
unsigned char force; /* Used to force sock release */
atomic_t packet_sent;
};
#endif
static int sk_count;
extern const struct proto_ops wanpipe_ops;
static unsigned long find_free_critical;
static void wanpipe_unlink_driver(struct sock *sk);
static void wanpipe_link_driver(struct net_device *dev, struct sock *sk);
static void wanpipe_wakeup_driver(struct sock *sk);
static int execute_command(struct sock *, unsigned char, unsigned int);
static int check_dev(struct net_device *dev, sdla_t *card);
struct net_device *wanpipe_find_free_dev(sdla_t *card);
static void wanpipe_unlink_card (struct sock *);
static int wanpipe_link_card (struct sock *);
static struct sock *wanpipe_make_new(struct sock *);
static struct sock *wanpipe_alloc_socket(void);
static inline int get_atomic_device(struct net_device *dev);
static int wanpipe_exec_cmd(struct sock *, int, unsigned int);
static int get_ioctl_cmd (struct sock *, void *);
static int set_ioctl_cmd (struct sock *, void *);
static void release_device(struct net_device *dev);
static void wanpipe_kill_sock_timer (unsigned long data);
static void wanpipe_kill_sock_irq (struct sock *);
static void wanpipe_kill_sock_accept (struct sock *);
static int wanpipe_do_bind(struct sock *sk, struct net_device *dev,
int protocol);
struct sock * get_newsk_from_skb (struct sk_buff *);
static int wanpipe_debug (struct sock *, void *);
static void wanpipe_delayed_transmit (unsigned long data);
static void release_driver(struct sock *);
static void start_cleanup_timer (struct sock *);
static void check_write_queue(struct sock *);
static int check_driver_busy (struct sock *);
/*============================================================
* wanpipe_rcv
*
* Wanpipe socket bottom half handler. This function
* is called by the WANPIPE device drivers to queue a
* incoming packet into the socket receive queue.
* Once the packet is queued, all processes waiting to
* read are woken up.
*
* During socket bind, this function is bounded into
* WANPIPE driver private.
*===========================================================*/
static int wanpipe_rcv(struct sk_buff *skb, struct net_device *dev,
struct sock *sk)
{
struct wan_sockaddr_ll *sll = (struct wan_sockaddr_ll*)skb->cb;
wanpipe_common_t *chan = dev->priv;
/*
* When we registered the protocol we saved the socket in the data
* field for just this event.
*/
skb->dev = dev;
sll->sll_family = AF_WANPIPE;
sll->sll_hatype = dev->type;
sll->sll_protocol = skb->protocol;
sll->sll_pkttype = skb->pkt_type;
sll->sll_ifindex = dev->ifindex;
sll->sll_halen = 0;
if (dev->hard_header_parse)
sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
/*
* WAN_PACKET_DATA : Data which should be passed up the receive queue.
* WAN_PACKET_ASYC : Asynchronous data like place call, which should
* be passed up the listening sock.
* WAN_PACKET_ERR : Asynchronous data like clear call or restart
* which should go into an error queue.
*/
switch (skb->pkt_type){
case WAN_PACKET_DATA:
if (sock_queue_rcv_skb(sk,skb)<0){
return -ENOMEM;
}
break;
case WAN_PACKET_CMD:
sk->sk_state = chan->state;
/* Bug fix: update Mar6.
* Do not set the sock lcn number here, since
* cmd is not guaranteed to be executed on the
* board, thus Lcn could be wrong */
sk->sk_data_ready(sk, skb->len);
kfree_skb(skb);
break;
case WAN_PACKET_ERR:
sk->sk_state = chan->state;
if (sock_queue_err_skb(sk,skb)<0){
return -ENOMEM;
}
break;
default:
printk(KERN_INFO "wansock: BH Illegal Packet Type Dropping\n");
kfree_skb(skb);
break;
}
//??????????????????????
// if (sk->sk_state == WANSOCK_DISCONNECTED){
// if (sk->sk_zapped) {
// //printk(KERN_INFO "wansock: Disconnected, killing early\n");
// wanpipe_unlink_driver(sk);
// sk->sk_bound_dev_if = 0;
// }
// }
return 0;
}
/*============================================================
* wanpipe_listen_rcv
*
* Wanpipe LISTEN socket bottom half handler. This function
* is called by the WANPIPE device drivers to queue an
* incoming call into the socket listening queue.
* Once the packet is queued, the waiting accept() process
* is woken up.
*
* During socket bind, this function is bounded into
* WANPIPE driver private.
*
* IMPORTANT NOTE:
* The accept call() is waiting for an skb packet
* which contains a pointer to a device structure.
*
* When we do a bind to a device structre, we
* bind a newly created socket into "chan->sk". Thus,
* when accept receives the skb packet, it will know
* from which dev it came form, and in turn it will know
* the address of the new sock.
*
* NOTE: This function gets called from driver ISR.
*===========================================================*/
static int wanpipe_listen_rcv (struct sk_buff *skb, struct sock *sk)
{
wanpipe_opt *wp = wp_sk(sk), *newwp;
struct wan_sockaddr_ll *sll = (struct wan_sockaddr_ll*)skb->cb;
struct sock *newsk;
struct net_device *dev;
sdla_t *card;
mbox_cmd_t *mbox_ptr;
wanpipe_common_t *chan;
/* Find a free device, if none found, all svc's are busy
*/
card = (sdla_t*)wp->card;
if (!card){
printk(KERN_INFO "wansock: LISTEN ERROR, No Card\n");
return -ENODEV;
}
dev = wanpipe_find_free_dev(card);
if (!dev){
printk(KERN_INFO "wansock: LISTEN ERROR, No Free Device\n");
return -ENODEV;
}
chan=dev->priv;
chan->state = WANSOCK_CONNECTING;
/* Allocate a new sock, which accept will bind
* and pass up to the user
*/
if ((newsk = wanpipe_make_new(sk)) == NULL){
release_device(dev);
return -ENOMEM;
}
/* Initialize the new sock structure
*/
newsk->sk_bound_dev_if = dev->ifindex;
newwp = wp_sk(newsk);
newwp->card = wp->card;
/* Insert the sock into the main wanpipe
* sock list.
*/
atomic_inc(&wanpipe_socks_nr);
/* Allocate and fill in the new Mail Box. Then
* bind the mail box to the sock. It will be
* used by the ioctl call to read call information
* and to execute commands.
*/
if ((mbox_ptr = kmalloc(sizeof(mbox_cmd_t), GFP_ATOMIC)) == NULL) {
wanpipe_kill_sock_irq (newsk);
release_device(dev);
return -ENOMEM;
}
memset(mbox_ptr, 0, sizeof(mbox_cmd_t));
memcpy(mbox_ptr,skb->data,skb->len);
/* Register the lcn on which incoming call came
* from. Thus, if we have to clear it, we know
* which lcn to clear
*/
newwp->lcn = mbox_ptr->cmd.lcn;
newwp->mbox = (void *)mbox_ptr;
DBG_PRINTK(KERN_INFO "NEWSOCK : Device %s, bind to lcn %i\n",
dev->name,mbox_ptr->cmd.lcn);
chan->lcn = mbox_ptr->cmd.lcn;
card->u.x.svc_to_dev_map[(chan->lcn%MAX_X25_LCN)] = dev;
sock_reset_flag(newsk, SOCK_ZAPPED);
newwp->num = htons(X25_PROT);
if (wanpipe_do_bind(newsk, dev, newwp->num)) {
wanpipe_kill_sock_irq (newsk);
release_device(dev);
return -EINVAL;
}
newsk->sk_state = WANSOCK_CONNECTING;
/* Fill in the standard sock address info */
sll->sll_family = AF_WANPIPE;
sll->sll_hatype = dev->type;
sll->sll_protocol = skb->protocol;
sll->sll_pkttype = skb->pkt_type;
sll->sll_ifindex = dev->ifindex;
sll->sll_halen = 0;
skb->dev = dev;
sk->sk_ack_backlog++;
/* We must do this manually, since the sock_queue_rcv_skb()
* function sets the skb->dev to NULL. However, we use
* the dev field in the accept function.*/
if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
(unsigned)sk->sk_rcvbuf) {
wanpipe_unlink_driver(newsk);
wanpipe_kill_sock_irq (newsk);
--sk->sk_ack_backlog;
return -ENOMEM;
}
skb_set_owner_r(skb, sk);
skb_queue_tail(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);
return 0;
}
/*============================================================
* wanpipe_make_new
*
* Create a new sock, and allocate a wanpipe private
* structure to it. Also, copy the important data
* from the original sock to the new sock.
*
* This function is used by wanpipe_listen_rcv() listen
* bottom half handler. A copy of the listening sock
* is created using this function.
*
*===========================================================*/
static struct sock *wanpipe_make_new(struct sock *osk)
{
struct sock *sk;
if (osk->sk_type != SOCK_RAW)
return NULL;
if ((sk = wanpipe_alloc_socket()) == NULL)
return NULL;
sk->sk_type = osk->sk_type;
sk->sk_socket = osk->sk_socket;
sk->sk_priority = osk->sk_priority;
sk->sk_protocol = osk->sk_protocol;
wp_sk(sk)->num = wp_sk(osk)->num;
sk->sk_rcvbuf = osk->sk_rcvbuf;
sk->sk_sndbuf = osk->sk_sndbuf;
sk->sk_state = WANSOCK_CONNECTING;
sk->sk_sleep = osk->sk_sleep;
if (sock_flag(osk, SOCK_DBG))
sock_set_flag(sk, SOCK_DBG);
return sk;
}
/*
* FIXME: wanpipe_opt has to include a sock in its definition and stop using
* sk_protinfo, but this code is not even compilable now, so lets leave it for
* later.
*/
static struct proto wanpipe_proto = {
.name = "WANPIPE",
.owner = THIS_MODULE,
.obj_size = sizeof(struct sock),
};
/*============================================================
* wanpipe_make_new
*
* Allocate memory for the a new sock, and sock
* private data.
*
* Increment the module use count.
*
* This function is used by wanpipe_create() and
* wanpipe_make_new() functions.
*
*===========================================================*/
static struct sock *wanpipe_alloc_socket(void)
{
struct sock *sk;
struct wanpipe_opt *wan_opt;
if ((sk = sk_alloc(PF_WANPIPE, GFP_ATOMIC, &wanpipe_proto, 1)) == NULL)
return NULL;
if ((wan_opt = kmalloc(sizeof(struct wanpipe_opt), GFP_ATOMIC)) == NULL) {
sk_free(sk);
return NULL;
}
memset(wan_opt, 0x00, sizeof(struct wanpipe_opt));
wp_sk(sk) = wan_opt;
/* Use timer to send data to the driver. This will act
* as a BH handler for sendmsg functions */
init_timer(&wan_opt->tx_timer);
wan_opt->tx_timer.data = (unsigned long)sk;
wan_opt->tx_timer.function = wanpipe_delayed_transmit;
sock_init_data(NULL, sk);
return sk;
}
/*============================================================
* wanpipe_sendmsg
*
* This function implements a sendto() system call,
* for AF_WANPIPE socket family.
* During socket bind() sk->sk_bound_dev_if is initialized
* to a correct network device. This number is used
* to find a network device to which the packet should
* be passed to.
*
* Each packet is queued into sk->sk_write_queue and
* delayed transmit bottom half handler is marked for
* execution.
*
* A socket must be in WANSOCK_CONNECTED state before
* a packet is queued into sk->sk_write_queue.
*===========================================================*/
static int wanpipe_sendmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, int len)
{
wanpipe_opt *wp;
struct sock *sk = sock->sk;
struct wan_sockaddr_ll *saddr=(struct wan_sockaddr_ll *)msg->msg_name;
struct sk_buff *skb;
struct net_device *dev;
unsigned short proto;
unsigned char *addr;
int ifindex, err, reserve = 0;
if (!sock_flag(sk, SOCK_ZAPPED))
return -ENETDOWN;
if (sk->sk_state != WANSOCK_CONNECTED)
return -ENOTCONN;
if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_CMSG_COMPAT))
return(-EINVAL);
/* it was <=, now one can send
* zero length packets */
if (len < sizeof(x25api_hdr_t))
return -EINVAL;
wp = wp_sk(sk);
if (saddr == NULL) {
ifindex = sk->sk_bound_dev_if;
proto = wp->num;
addr = NULL;
}else{
if (msg->msg_namelen < sizeof(struct wan_sockaddr_ll)){
return -EINVAL;
}
ifindex = sk->sk_bound_dev_if;
proto = saddr->sll_protocol;
addr = saddr->sll_addr;
}
dev = dev_get_by_index(ifindex);
if (dev == NULL){
printk(KERN_INFO "wansock: Send failed, dev index: %i\n",ifindex);
return -ENXIO;
}
dev_put(dev);
if (sock->type == SOCK_RAW)
reserve = dev->hard_header_len;
if (len > dev->mtu+reserve){
return -EMSGSIZE;
}
skb = sock_alloc_send_skb(sk, len + LL_RESERVED_SPACE(dev),
msg->msg_flags & MSG_DONTWAIT, &err);
if (skb==NULL){
goto out_unlock;
}
skb_reserve(skb, LL_RESERVED_SPACE(dev));
skb->nh.raw = skb->data;
/* Returns -EFAULT on error */
err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
if (err){
goto out_free;
}
if (dev->hard_header) {
int res;
err = -EINVAL;
res = dev->hard_header(skb, dev, ntohs(proto), addr, NULL, len);
if (res<0){
goto out_free;
}
}
skb->protocol = proto;
skb->dev = dev;
skb->priority = sk->sk_priority;
skb->pkt_type = WAN_PACKET_DATA;
err = -ENETDOWN;
if (!(dev->flags & IFF_UP))
goto out_free;
if (atomic_read(&sk->sk_wmem_alloc) + skb->truesize >
(unsigned int)sk->sk_sndbuf){
kfree_skb(skb);
return -ENOBUFS;
}
skb_queue_tail(&sk->sk_write_queue,skb);
atomic_inc(&wp->packet_sent);
if (!(test_and_set_bit(0, &wp->timer)))
mod_timer(&wp->tx_timer, jiffies + 1);
return(len);
out_free:
kfree_skb(skb);
out_unlock:
return err;
}
/*============================================================
* wanpipe_delayed_tarnsmit
*
* Transmit bottom half handler. It dequeues packets
* from sk->sk_write_queue and passes them to the
* driver. If the driver is busy, the packet is
* re-enqueued.
*
* Packet Sent counter is decremented on successful
* transmission.
*===========================================================*/
static void wanpipe_delayed_transmit (unsigned long data)
{
struct sock *sk=(struct sock *)data;
struct sk_buff *skb;
wanpipe_opt *wp = wp_sk(sk);
struct net_device *dev = wp->dev;
sdla_t *card = (sdla_t*)wp->card;
if (!card || !dev){
clear_bit(0, &wp->timer);
DBG_PRINTK(KERN_INFO "wansock: Transmit delay, no dev or card\n");
return;
}
if (sk->sk_state != WANSOCK_CONNECTED || !sock_flag(sk, SOCK_ZAPPED)) {
clear_bit(0, &wp->timer);
DBG_PRINTK(KERN_INFO "wansock: Tx Timer, State not CONNECTED\n");
return;
}
/* If driver is executing command, we must offload
* the board by not sending data. Otherwise a
* pending command will never get a free buffer
* to execute */
if (atomic_read(&card->u.x.command_busy)){
wp->tx_timer.expires = jiffies + SLOW_BACKOFF;
add_timer(&wp->tx_timer);
DBG_PRINTK(KERN_INFO "wansock: Tx Timer, command bys BACKOFF\n");
return;
}
if (test_and_set_bit(0,&wanpipe_tx_critical)){
printk(KERN_INFO "WanSock: Tx timer critical %s\n",dev->name);
wp->tx_timer.expires = jiffies + SLOW_BACKOFF;
add_timer(&wp->tx_timer);
return;
}
/* Check for a packet in the fifo and send */
if ((skb = skb_dequeue(&sk->sk_write_queue)) != NULL){
if (dev->hard_start_xmit(skb, dev) != 0){
/* Driver failed to transmit, re-enqueue
* the packet and retry again later */
skb_queue_head(&sk->sk_write_queue,skb);
clear_bit(0,&wanpipe_tx_critical);
return;
}else{
/* Packet Sent successful. Check for more packets
* if more packets, re-trigger the transmit routine
* other wise exit
*/
atomic_dec(&wp->packet_sent);
if (skb_peek(&sk->sk_write_queue) == NULL) {
/* If there is nothing to send, kick
* the poll routine, which will trigger
* the application to send more data */
sk->sk_data_ready(sk, 0);
clear_bit(0, &wp->timer);
}else{
/* Reschedule as fast as possible */
wp->tx_timer.expires = jiffies + 1;
add_timer(&wp->tx_timer);
}
}
}
clear_bit(0,&wanpipe_tx_critical);
}
/*============================================================
* execute_command
*
* Execute x25api commands. The atomic variable
* chan->command is used to indicate to the driver that
* command is pending for execution. The acutal command
* structure is placed into a sock mbox structure
* (wp_sk(sk)->mbox).
*
* The sock private structure, mbox is
* used as shared memory between sock and the driver.
* Driver uses the sock mbox to execute the command
* and return the result.
*
* For all command except PLACE CALL, the function
* waits for the result. PLACE CALL can be ether
* blocking or nonblocking. The user sets this option
* via ioctl call.
*===========================================================*/
static int execute_command(struct sock *sk, unsigned char cmd, unsigned int flags)
{
wanpipe_opt *wp = wp_sk(sk);
struct net_device *dev;
wanpipe_common_t *chan=NULL;
int err=0;
DECLARE_WAITQUEUE(wait, current);
dev = dev_get_by_index(sk->sk_bound_dev_if);
if (dev == NULL){
printk(KERN_INFO "wansock: Exec failed no dev %i\n",
sk->sk_bound_dev_if);
return -ENODEV;
}
dev_put(dev);
if ((chan=dev->priv) == NULL){
printk(KERN_INFO "wansock: Exec cmd failed no priv area\n");
return -ENODEV;
}
if (atomic_read(&chan->command)){
printk(KERN_INFO "wansock: ERROR: Command already running %x, %s\n",
atomic_read(&chan->command),dev->name);
return -EINVAL;
}
if (!wp->mbox) {
printk(KERN_INFO "wansock: In execute without MBOX\n");
return -EINVAL;
}
((mbox_cmd_t*)wp->mbox)->cmd.command = cmd;
((mbox_cmd_t*)wp->mbox)->cmd.lcn = wp->lcn;
((mbox_cmd_t*)wp->mbox)->cmd.result = 0x7F;
if (flags & O_NONBLOCK){
cmd |= 0x80;
atomic_set(&chan->command, cmd);
}else{
atomic_set(&chan->command, cmd);
}
add_wait_queue(sk->sk_sleep,&wait);
current->state = TASK_INTERRUPTIBLE;
for (;;){
if (((mbox_cmd_t*)wp->mbox)->cmd.result != 0x7F) {
err = 0;
break;
}
if (signal_pending(current)) {
err = -ERESTARTSYS;
break;
}
schedule();
}
current->state = TASK_RUNNING;
remove_wait_queue(sk->sk_sleep,&wait);
return err;
}
/*============================================================
* wanpipe_destroy_timer
*
* Used by wanpipe_release, to delay release of
* the socket.
*===========================================================*/
static void wanpipe_destroy_timer(unsigned long data)
{
struct sock *sk=(struct sock *)data;
wanpipe_opt *wp = wp_sk(sk);
if ((!atomic_read(&sk->sk_wmem_alloc) &&
!atomic_read(&sk->sk_rmem_alloc)) ||
(++wp->force == 5)) {
if (atomic_read(&sk->sk_wmem_alloc) ||
atomic_read(&sk->sk_rmem_alloc))
printk(KERN_INFO "wansock: Warning, Packet Discarded due to sock shutdown!\n");
kfree(wp);
wp_sk(sk) = NULL;
if (atomic_read(&sk->sk_refcnt) != 1) {
atomic_set(&sk->sk_refcnt, 1);
DBG_PRINTK(KERN_INFO "wansock: Error, wrong reference count: %i ! :delay.\n",
atomic_read(&sk->sk_refcnt));
}
sock_put(sk);
atomic_dec(&wanpipe_socks_nr);
return;
}
sk->sk_timer.expires = jiffies + 5 * HZ;
add_timer(&sk->sk_timer);
printk(KERN_INFO "wansock: packet sk destroy delayed\n");
}
/*============================================================
* wanpipe_unlink_driver
*
* When the socket is released, this function is
* used to remove links that bind the sock and the
* driver together.
*===========================================================*/
static void wanpipe_unlink_driver (struct sock *sk)
{
struct net_device *dev;
wanpipe_common_t *chan=NULL;
sock_reset_flag(sk, SOCK_ZAPPED);
sk->sk_state = WANSOCK_DISCONNECTED;
wp_sk(sk)->dev = NULL;
dev = dev_get_by_index(sk->sk_bound_dev_if);
if (!dev){
printk(KERN_INFO "wansock: No dev on release\n");
return;
}
dev_put(dev);
if ((chan = dev->priv) == NULL){
printk(KERN_INFO "wansock: No Priv Area on release\n");
return;
}
set_bit(0,&chan->common_critical);
chan->sk=NULL;
chan->func=NULL;
chan->mbox=NULL;
chan->tx_timer=NULL;
clear_bit(0,&chan->common_critical);
release_device(dev);
return;
}
/*============================================================
* wanpipe_link_driver
*
* Upon successful bind(), sock is linked to a driver
* by binding in the wanpipe_rcv() bottom half handler
* to the driver function pointer, as well as sock and
* sock mailbox addresses. This way driver can pass
* data up the socket.
*===========================================================*/
static void wanpipe_link_driver(struct net_device *dev, struct sock *sk)
{
wanpipe_opt *wp = wp_sk(sk);
wanpipe_common_t *chan = dev->priv;
if (!chan)
return;
set_bit(0,&chan->common_critical);
chan->sk=sk;
chan->func=wanpipe_rcv;
chan->mbox = wp->mbox;
chan->tx_timer = &wp->tx_timer;
wp->dev = dev;
sock_set_flag(sk, SOCK_ZAPPED);
clear_bit(0,&chan->common_critical);
}
/*============================================================
* release_device
*
* During sock release, clear a critical bit, which
* marks the device a being taken.
*===========================================================*/
static void release_device(struct net_device *dev)
{
wanpipe_common_t *chan=dev->priv;
clear_bit(0,(void*)&chan->rw_bind);
}
/*============================================================
* wanpipe_release
*
* Close a PACKET socket. This is fairly simple. We
* immediately go to 'closed' state and remove our
* protocol entry in the device list.
*===========================================================*/
static int wanpipe_release(struct socket *sock)
{
wanpipe_opt *wp;
struct sock *sk = sock->sk;
if (!sk)
return 0;
wp = wp_sk(sk);
check_write_queue(sk);
/* Kill the tx timer, if we don't kill it now, the timer
* will run after we kill the sock. Timer code will
* try to access the sock which has been killed and cause
* kernel panic */
del_timer(&wp->tx_timer);
/*
* Unhook packet receive handler.
*/
if (wp->num == htons(X25_PROT) &&
sk->sk_state != WANSOCK_DISCONNECTED && sock_flag(sk, SOCK_ZAPPED)) {
struct net_device *dev = dev_get_by_index(sk->sk_bound_dev_if);
wanpipe_common_t *chan;
if (dev){
chan=dev->priv;
atomic_set(&chan->disconnect,1);
DBG_PRINTK(KERN_INFO "wansock: Sending Clear Indication %i\n",
sk->sk_state);
dev_put(dev);
}
}
set_bit(1,&wanpipe_tx_critical);
write_lock(&wanpipe_sklist_lock);
sk_del_node_init(sk);
write_unlock(&wanpipe_sklist_lock);
clear_bit(1,&wanpipe_tx_critical);
release_driver(sk);