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af_x25.c
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af_x25.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* X.25 Packet Layer release 002
*
* This is ALPHA test software. This code may break your machine,
* randomly fail to work with new releases, misbehave and/or generally
* screw up. It might even work.
*
* This code REQUIRES 2.1.15 or higher
*
* History
* X.25 001 Jonathan Naylor Started coding.
* X.25 002 Jonathan Naylor Centralised disconnect handling.
* New timer architecture.
* 2000-03-11 Henner Eisen MSG_EOR handling more POSIX compliant.
* 2000-03-22 Daniela Squassoni Allowed disabling/enabling of
* facilities negotiation and increased
* the throughput upper limit.
* 2000-08-27 Arnaldo C. Melo s/suser/capable/ + micro cleanups
* 2000-09-04 Henner Eisen Set sock->state in x25_accept().
* Fixed x25_output() related skb leakage.
* 2000-10-02 Henner Eisen Made x25_kick() single threaded per socket.
* 2000-10-27 Henner Eisen MSG_DONTWAIT for fragment allocation.
* 2000-11-14 Henner Eisen Closing datalink from NETDEV_GOING_DOWN
* 2002-10-06 Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
* x25_proc.c, using seq_file
* 2005-04-02 Shaun Pereira Selective sub address matching
* with call user data
* 2005-04-15 Shaun Pereira Fast select with no restriction on
* response
*/
#define pr_fmt(fmt) "X25: " fmt
#include <linux/module.h>
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched/signal.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/tcp_states.h>
#include <linux/uaccess.h>
#include <linux/fcntl.h>
#include <linux/termios.h> /* For TIOCINQ/OUTQ */
#include <linux/notifier.h>
#include <linux/init.h>
#include <linux/compat.h>
#include <linux/ctype.h>
#include <net/x25.h>
#include <net/compat.h>
int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
int sysctl_x25_call_request_timeout = X25_DEFAULT_T21;
int sysctl_x25_reset_request_timeout = X25_DEFAULT_T22;
int sysctl_x25_clear_request_timeout = X25_DEFAULT_T23;
int sysctl_x25_ack_holdback_timeout = X25_DEFAULT_T2;
int sysctl_x25_forward = 0;
HLIST_HEAD(x25_list);
DEFINE_RWLOCK(x25_list_lock);
static const struct proto_ops x25_proto_ops;
static const struct x25_address null_x25_address = {" "};
#ifdef CONFIG_COMPAT
struct compat_x25_subscrip_struct {
char device[200-sizeof(compat_ulong_t)];
compat_ulong_t global_facil_mask;
compat_uint_t extended;
};
#endif
int x25_parse_address_block(struct sk_buff *skb,
struct x25_address *called_addr,
struct x25_address *calling_addr)
{
unsigned char len;
int needed;
int rc;
if (!pskb_may_pull(skb, 1)) {
/* packet has no address block */
rc = 0;
goto empty;
}
len = *skb->data;
needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2;
if (!pskb_may_pull(skb, needed)) {
/* packet is too short to hold the addresses it claims
to hold */
rc = -1;
goto empty;
}
return x25_addr_ntoa(skb->data, called_addr, calling_addr);
empty:
*called_addr->x25_addr = 0;
*calling_addr->x25_addr = 0;
return rc;
}
int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
struct x25_address *calling_addr)
{
unsigned int called_len, calling_len;
char *called, *calling;
unsigned int i;
called_len = (*p >> 0) & 0x0F;
calling_len = (*p >> 4) & 0x0F;
called = called_addr->x25_addr;
calling = calling_addr->x25_addr;
p++;
for (i = 0; i < (called_len + calling_len); i++) {
if (i < called_len) {
if (i % 2 != 0) {
*called++ = ((*p >> 0) & 0x0F) + '0';
p++;
} else {
*called++ = ((*p >> 4) & 0x0F) + '0';
}
} else {
if (i % 2 != 0) {
*calling++ = ((*p >> 0) & 0x0F) + '0';
p++;
} else {
*calling++ = ((*p >> 4) & 0x0F) + '0';
}
}
}
*called = *calling = '\0';
return 1 + (called_len + calling_len + 1) / 2;
}
int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
struct x25_address *calling_addr)
{
unsigned int called_len, calling_len;
char *called, *calling;
int i;
called = called_addr->x25_addr;
calling = calling_addr->x25_addr;
called_len = strlen(called);
calling_len = strlen(calling);
*p++ = (calling_len << 4) | (called_len << 0);
for (i = 0; i < (called_len + calling_len); i++) {
if (i < called_len) {
if (i % 2 != 0) {
*p |= (*called++ - '0') << 0;
p++;
} else {
*p = 0x00;
*p |= (*called++ - '0') << 4;
}
} else {
if (i % 2 != 0) {
*p |= (*calling++ - '0') << 0;
p++;
} else {
*p = 0x00;
*p |= (*calling++ - '0') << 4;
}
}
}
return 1 + (called_len + calling_len + 1) / 2;
}
/*
* Socket removal during an interrupt is now safe.
*/
static void x25_remove_socket(struct sock *sk)
{
write_lock_bh(&x25_list_lock);
sk_del_node_init(sk);
write_unlock_bh(&x25_list_lock);
}
/*
* Kill all bound sockets on a dropped device.
*/
static void x25_kill_by_device(struct net_device *dev)
{
struct sock *s;
write_lock_bh(&x25_list_lock);
sk_for_each(s, &x25_list)
if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
x25_disconnect(s, ENETUNREACH, 0, 0);
write_unlock_bh(&x25_list_lock);
}
/*
* Handle device status changes.
*/
static int x25_device_event(struct notifier_block *this, unsigned long event,
void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct x25_neigh *nb;
if (!net_eq(dev_net(dev), &init_net))
return NOTIFY_DONE;
if (dev->type == ARPHRD_X25
#if IS_ENABLED(CONFIG_LLC)
|| dev->type == ARPHRD_ETHER
#endif
) {
switch (event) {
case NETDEV_UP:
x25_link_device_up(dev);
break;
case NETDEV_GOING_DOWN:
nb = x25_get_neigh(dev);
if (nb) {
x25_terminate_link(nb);
x25_neigh_put(nb);
}
break;
case NETDEV_DOWN:
x25_kill_by_device(dev);
x25_route_device_down(dev);
x25_link_device_down(dev);
break;
}
}
return NOTIFY_DONE;
}
/*
* Add a socket to the bound sockets list.
*/
static void x25_insert_socket(struct sock *sk)
{
write_lock_bh(&x25_list_lock);
sk_add_node(sk, &x25_list);
write_unlock_bh(&x25_list_lock);
}
/*
* Find a socket that wants to accept the Call Request we just
* received. Check the full list for an address/cud match.
* If no cuds match return the next_best thing, an address match.
* Note: if a listening socket has cud set it must only get calls
* with matching cud.
*/
static struct sock *x25_find_listener(struct x25_address *addr,
struct sk_buff *skb)
{
struct sock *s;
struct sock *next_best;
read_lock_bh(&x25_list_lock);
next_best = NULL;
sk_for_each(s, &x25_list)
if ((!strcmp(addr->x25_addr,
x25_sk(s)->source_addr.x25_addr) ||
!strcmp(x25_sk(s)->source_addr.x25_addr,
null_x25_address.x25_addr)) &&
s->sk_state == TCP_LISTEN) {
/*
* Found a listening socket, now check the incoming
* call user data vs this sockets call user data
*/
if (x25_sk(s)->cudmatchlength > 0 &&
skb->len >= x25_sk(s)->cudmatchlength) {
if((memcmp(x25_sk(s)->calluserdata.cuddata,
skb->data,
x25_sk(s)->cudmatchlength)) == 0) {
sock_hold(s);
goto found;
}
} else
next_best = s;
}
if (next_best) {
s = next_best;
sock_hold(s);
goto found;
}
s = NULL;
found:
read_unlock_bh(&x25_list_lock);
return s;
}
/*
* Find a connected X.25 socket given my LCI and neighbour.
*/
static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
{
struct sock *s;
sk_for_each(s, &x25_list)
if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
sock_hold(s);
goto found;
}
s = NULL;
found:
return s;
}
struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
{
struct sock *s;
read_lock_bh(&x25_list_lock);
s = __x25_find_socket(lci, nb);
read_unlock_bh(&x25_list_lock);
return s;
}
/*
* Find a unique LCI for a given device.
*/
static unsigned int x25_new_lci(struct x25_neigh *nb)
{
unsigned int lci = 1;
struct sock *sk;
while ((sk = x25_find_socket(lci, nb)) != NULL) {
sock_put(sk);
if (++lci == 4096) {
lci = 0;
break;
}
cond_resched();
}
return lci;
}
/*
* Deferred destroy.
*/
static void __x25_destroy_socket(struct sock *);
/*
* handler for deferred kills.
*/
static void x25_destroy_timer(struct timer_list *t)
{
struct sock *sk = from_timer(sk, t, sk_timer);
x25_destroy_socket_from_timer(sk);
}
/*
* This is called from user mode and the timers. 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.
* Not static as it's used by the timer
*/
static void __x25_destroy_socket(struct sock *sk)
{
struct sk_buff *skb;
x25_stop_heartbeat(sk);
x25_stop_timer(sk);
x25_remove_socket(sk);
x25_clear_queues(sk); /* Flush the queues */
while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
if (skb->sk != sk) { /* A pending connection */
/*
* Queue the unaccepted socket for death
*/
skb->sk->sk_state = TCP_LISTEN;
sock_set_flag(skb->sk, SOCK_DEAD);
x25_start_heartbeat(skb->sk);
x25_sk(skb->sk)->state = X25_STATE_0;
}
kfree_skb(skb);
}
if (sk_has_allocations(sk)) {
/* Defer: outstanding buffers */
sk->sk_timer.expires = jiffies + 10 * HZ;
sk->sk_timer.function = x25_destroy_timer;
add_timer(&sk->sk_timer);
} else {
/* drop last reference so sock_put will free */
__sock_put(sk);
}
}
void x25_destroy_socket_from_timer(struct sock *sk)
{
sock_hold(sk);
bh_lock_sock(sk);
__x25_destroy_socket(sk);
bh_unlock_sock(sk);
sock_put(sk);
}
/*
* Handling for system calls applied via the various interfaces to a
* X.25 socket object.
*/
static int x25_setsockopt(struct socket *sock, int level, int optname,
sockptr_t optval, unsigned int optlen)
{
int opt;
struct sock *sk = sock->sk;
int rc = -ENOPROTOOPT;
if (level != SOL_X25 || optname != X25_QBITINCL)
goto out;
rc = -EINVAL;
if (optlen < sizeof(int))
goto out;
rc = -EFAULT;
if (copy_from_sockptr(&opt, optval, sizeof(int)))
goto out;
if (opt)
set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
else
clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
rc = 0;
out:
return rc;
}
static int x25_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct sock *sk = sock->sk;
int val, len, rc = -ENOPROTOOPT;
if (level != SOL_X25 || optname != X25_QBITINCL)
goto out;
rc = -EFAULT;
if (get_user(len, optlen))
goto out;
len = min_t(unsigned int, len, sizeof(int));
rc = -EINVAL;
if (len < 0)
goto out;
rc = -EFAULT;
if (put_user(len, optlen))
goto out;
val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
out:
return rc;
}
static int x25_listen(struct socket *sock, int backlog)
{
struct sock *sk = sock->sk;
int rc = -EOPNOTSUPP;
lock_sock(sk);
if (sk->sk_state != TCP_LISTEN) {
memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
sk->sk_max_ack_backlog = backlog;
sk->sk_state = TCP_LISTEN;
rc = 0;
}
release_sock(sk);
return rc;
}
static struct proto x25_proto = {
.name = "X25",
.owner = THIS_MODULE,
.obj_size = sizeof(struct x25_sock),
};
static struct sock *x25_alloc_socket(struct net *net, int kern)
{
struct x25_sock *x25;
struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
if (!sk)
goto out;
sock_init_data(NULL, sk);
x25 = x25_sk(sk);
skb_queue_head_init(&x25->ack_queue);
skb_queue_head_init(&x25->fragment_queue);
skb_queue_head_init(&x25->interrupt_in_queue);
skb_queue_head_init(&x25->interrupt_out_queue);
out:
return sk;
}
static int x25_create(struct net *net, struct socket *sock, int protocol,
int kern)
{
struct sock *sk;
struct x25_sock *x25;
int rc = -EAFNOSUPPORT;
if (!net_eq(net, &init_net))
goto out;
rc = -ESOCKTNOSUPPORT;
if (sock->type != SOCK_SEQPACKET)
goto out;
rc = -EINVAL;
if (protocol)
goto out;
rc = -ENOBUFS;
if ((sk = x25_alloc_socket(net, kern)) == NULL)
goto out;
x25 = x25_sk(sk);
sock_init_data(sock, sk);
x25_init_timers(sk);
sock->ops = &x25_proto_ops;
sk->sk_protocol = protocol;
sk->sk_backlog_rcv = x25_backlog_rcv;
x25->t21 = sysctl_x25_call_request_timeout;
x25->t22 = sysctl_x25_reset_request_timeout;
x25->t23 = sysctl_x25_clear_request_timeout;
x25->t2 = sysctl_x25_ack_holdback_timeout;
x25->state = X25_STATE_0;
x25->cudmatchlength = 0;
set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags); /* normally no cud */
/* on call accept */
x25->facilities.winsize_in = X25_DEFAULT_WINDOW_SIZE;
x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
x25->facilities.pacsize_in = X25_DEFAULT_PACKET_SIZE;
x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
x25->facilities.throughput = 0; /* by default don't negotiate
throughput */
x25->facilities.reverse = X25_DEFAULT_REVERSE;
x25->dte_facilities.calling_len = 0;
x25->dte_facilities.called_len = 0;
memset(x25->dte_facilities.called_ae, '\0',
sizeof(x25->dte_facilities.called_ae));
memset(x25->dte_facilities.calling_ae, '\0',
sizeof(x25->dte_facilities.calling_ae));
rc = 0;
out:
return rc;
}
static struct sock *x25_make_new(struct sock *osk)
{
struct sock *sk = NULL;
struct x25_sock *x25, *ox25;
if (osk->sk_type != SOCK_SEQPACKET)
goto out;
if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
goto out;
x25 = x25_sk(sk);
sk->sk_type = osk->sk_type;
sk->sk_priority = osk->sk_priority;
sk->sk_protocol = osk->sk_protocol;
sk->sk_rcvbuf = osk->sk_rcvbuf;
sk->sk_sndbuf = osk->sk_sndbuf;
sk->sk_state = TCP_ESTABLISHED;
sk->sk_backlog_rcv = osk->sk_backlog_rcv;
sock_copy_flags(sk, osk);
ox25 = x25_sk(osk);
x25->t21 = ox25->t21;
x25->t22 = ox25->t22;
x25->t23 = ox25->t23;
x25->t2 = ox25->t2;
x25->flags = ox25->flags;
x25->facilities = ox25->facilities;
x25->dte_facilities = ox25->dte_facilities;
x25->cudmatchlength = ox25->cudmatchlength;
clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
x25_init_timers(sk);
out:
return sk;
}
static int x25_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct x25_sock *x25;
if (!sk)
return 0;
x25 = x25_sk(sk);
sock_hold(sk);
lock_sock(sk);
switch (x25->state) {
case X25_STATE_0:
case X25_STATE_2:
x25_disconnect(sk, 0, 0, 0);
__x25_destroy_socket(sk);
goto out;
case X25_STATE_1:
case X25_STATE_3:
case X25_STATE_4:
x25_clear_queues(sk);
x25_write_internal(sk, X25_CLEAR_REQUEST);
x25_start_t23timer(sk);
x25->state = X25_STATE_2;
sk->sk_state = TCP_CLOSE;
sk->sk_shutdown |= SEND_SHUTDOWN;
sk->sk_state_change(sk);
sock_set_flag(sk, SOCK_DEAD);
sock_set_flag(sk, SOCK_DESTROY);
break;
case X25_STATE_5:
x25_write_internal(sk, X25_CLEAR_REQUEST);
x25_disconnect(sk, 0, 0, 0);
__x25_destroy_socket(sk);
goto out;
}
sock_orphan(sk);
out:
release_sock(sk);
sock_put(sk);
return 0;
}
static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
struct sock *sk = sock->sk;
struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
int len, i, rc = 0;
if (addr_len != sizeof(struct sockaddr_x25) ||
addr->sx25_family != AF_X25) {
rc = -EINVAL;
goto out;
}
/* check for the null_x25_address */
if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
len = strlen(addr->sx25_addr.x25_addr);
for (i = 0; i < len; i++) {
if (!isdigit(addr->sx25_addr.x25_addr[i])) {
rc = -EINVAL;
goto out;
}
}
}
lock_sock(sk);
if (sock_flag(sk, SOCK_ZAPPED)) {
x25_sk(sk)->source_addr = addr->sx25_addr;
x25_insert_socket(sk);
sock_reset_flag(sk, SOCK_ZAPPED);
} else {
rc = -EINVAL;
}
release_sock(sk);
SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
out:
return rc;
}
static int x25_wait_for_connection_establishment(struct sock *sk)
{
DECLARE_WAITQUEUE(wait, current);
int rc;
add_wait_queue_exclusive(sk_sleep(sk), &wait);
for (;;) {
__set_current_state(TASK_INTERRUPTIBLE);
rc = -ERESTARTSYS;
if (signal_pending(current))
break;
rc = sock_error(sk);
if (rc) {
sk->sk_socket->state = SS_UNCONNECTED;
break;
}
rc = 0;
if (sk->sk_state != TCP_ESTABLISHED) {
release_sock(sk);
schedule();
lock_sock(sk);
} else
break;
}
__set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk), &wait);
return rc;
}
static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
int addr_len, int flags)
{
struct sock *sk = sock->sk;
struct x25_sock *x25 = x25_sk(sk);
struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
struct x25_route *rt;
int rc = 0;
lock_sock(sk);
if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
sock->state = SS_CONNECTED;
goto out; /* Connect completed during a ERESTARTSYS event */
}
rc = -ECONNREFUSED;
if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
sock->state = SS_UNCONNECTED;
goto out;
}
rc = -EISCONN; /* No reconnect on a seqpacket socket */
if (sk->sk_state == TCP_ESTABLISHED)
goto out;
rc = -EALREADY; /* Do nothing if call is already in progress */
if (sk->sk_state == TCP_SYN_SENT)
goto out;
sk->sk_state = TCP_CLOSE;
sock->state = SS_UNCONNECTED;
rc = -EINVAL;
if (addr_len != sizeof(struct sockaddr_x25) ||
addr->sx25_family != AF_X25)
goto out;
rc = -ENETUNREACH;
rt = x25_get_route(&addr->sx25_addr);
if (!rt)
goto out;
x25->neighbour = x25_get_neigh(rt->dev);
if (!x25->neighbour)
goto out_put_route;
x25_limit_facilities(&x25->facilities, x25->neighbour);
x25->lci = x25_new_lci(x25->neighbour);
if (!x25->lci)
goto out_put_neigh;
rc = -EINVAL;
if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
goto out_put_neigh;
if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
memset(&x25->source_addr, '\0', X25_ADDR_LEN);
x25->dest_addr = addr->sx25_addr;
/* Move to connecting socket, start sending Connect Requests */
sock->state = SS_CONNECTING;
sk->sk_state = TCP_SYN_SENT;
x25->state = X25_STATE_1;
x25_write_internal(sk, X25_CALL_REQUEST);
x25_start_heartbeat(sk);
x25_start_t21timer(sk);
/* Now the loop */
rc = -EINPROGRESS;
if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
goto out;
rc = x25_wait_for_connection_establishment(sk);
if (rc)
goto out_put_neigh;
sock->state = SS_CONNECTED;
rc = 0;
out_put_neigh:
if (rc && x25->neighbour) {
read_lock_bh(&x25_list_lock);
x25_neigh_put(x25->neighbour);
x25->neighbour = NULL;
read_unlock_bh(&x25_list_lock);
x25->state = X25_STATE_0;
}
out_put_route:
x25_route_put(rt);
out:
release_sock(sk);
return rc;
}
static int x25_wait_for_data(struct sock *sk, long timeout)
{
DECLARE_WAITQUEUE(wait, current);
int rc = 0;
add_wait_queue_exclusive(sk_sleep(sk), &wait);
for (;;) {
__set_current_state(TASK_INTERRUPTIBLE);
if (sk->sk_shutdown & RCV_SHUTDOWN)
break;
rc = -ERESTARTSYS;
if (signal_pending(current))
break;
rc = -EAGAIN;
if (!timeout)
break;
rc = 0;
if (skb_queue_empty(&sk->sk_receive_queue)) {
release_sock(sk);
timeout = schedule_timeout(timeout);
lock_sock(sk);
} else
break;
}
__set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk), &wait);
return rc;
}
static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
bool kern)
{
struct sock *sk = sock->sk;
struct sock *newsk;
struct sk_buff *skb;
int rc = -EINVAL;
if (!sk)
goto out;
rc = -EOPNOTSUPP;
if (sk->sk_type != SOCK_SEQPACKET)
goto out;
lock_sock(sk);
rc = -EINVAL;
if (sk->sk_state != TCP_LISTEN)
goto out2;
rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
if (rc)
goto out2;
skb = skb_dequeue(&sk->sk_receive_queue);
rc = -EINVAL;
if (!skb->sk)
goto out2;
newsk = skb->sk;
sock_graft(newsk, newsock);
/* Now attach up the new socket */
skb->sk = NULL;
kfree_skb(skb);
sk_acceptq_removed(sk);
newsock->state = SS_CONNECTED;
rc = 0;
out2:
release_sock(sk);
out:
return rc;
}
static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
int peer)
{
struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
struct sock *sk = sock->sk;
struct x25_sock *x25 = x25_sk(sk);
int rc = 0;
if (peer) {
if (sk->sk_state != TCP_ESTABLISHED) {
rc = -ENOTCONN;
goto out;
}
sx25->sx25_addr = x25->dest_addr;
} else
sx25->sx25_addr = x25->source_addr;
sx25->sx25_family = AF_X25;
rc = sizeof(*sx25);
out:
return rc;
}
int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
unsigned int lci)
{
struct sock *sk;
struct sock *make;
struct x25_sock *makex25;
struct x25_address source_addr, dest_addr;
struct x25_facilities facilities;
struct x25_dte_facilities dte_facilities;
int len, addr_len, rc;
/*
* Remove the LCI and frame type.
*/
skb_pull(skb, X25_STD_MIN_LEN);
/*
* Extract the X.25 addresses and convert them to ASCII strings,
* and remove them.
*
* Address block is mandatory in call request packets
*/
addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
if (addr_len <= 0)
goto out_clear_request;
skb_pull(skb, addr_len);
/*
* Get the length of the facilities, skip past them for the moment
* get the call user data because this is needed to determine
* the correct listener
*
* Facilities length is mandatory in call request packets
*/
if (!pskb_may_pull(skb, 1))
goto out_clear_request;
len = skb->data[0] + 1;
if (!pskb_may_pull(skb, len))
goto out_clear_request;
skb_pull(skb,len);
/*
* Ensure that the amount of call user data is valid.
*/
if (skb->len > X25_MAX_CUD_LEN)
goto out_clear_request;
/*
* Get all the call user data so it can be used in
* x25_find_listener and skb_copy_from_linear_data up ahead.
*/
if (!pskb_may_pull(skb, skb->len))
goto out_clear_request;
/*
* Find a listener for the particular address/cud pair.
*/
sk = x25_find_listener(&source_addr,skb);
skb_push(skb,len);
if (sk != NULL && sk_acceptq_is_full(sk)) {
goto out_sock_put;
}