af_rose.c

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	len = min(len, sizeof(int));

	if (put_user(len, optlen))
		return -EFAULT;

	return copy_to_user(optval, &val, len) ? -EFAULT : 0;
}

static int rose_listen(struct socket *sock, int backlog)
{
	struct sock *sk = sock->sk;

	if (sk->state != TCP_LISTEN) {
		sk->protinfo.rose->dest_ndigis = 0;
		memset(&sk->protinfo.rose->dest_addr, '\0', ROSE_ADDR_LEN);
		memset(&sk->protinfo.rose->dest_call, '\0', AX25_ADDR_LEN);
		memset(sk->protinfo.rose->dest_digis, '\0', AX25_ADDR_LEN*ROSE_MAX_DIGIS);
		sk->max_ack_backlog = backlog;
		sk->state           = TCP_LISTEN;
		return 0;
	}

	return -EOPNOTSUPP;
}

static int rose_create(struct socket *sock, int protocol)
{
	struct sock *sk;
	rose_cb *rose;

	if (sock->type != SOCK_SEQPACKET || protocol != 0)
		return -ESOCKTNOSUPPORT;

	if ((sk = rose_alloc_sock()) == NULL)
		return -ENOMEM;

	rose = sk->protinfo.rose;

	sock_init_data(sock, sk);
	
	skb_queue_head_init(&rose->ack_queue);
#ifdef M_BIT
	skb_queue_head_init(&rose->frag_queue);
	rose->fraglen    = 0;
#endif

	sock->ops    = &rose_proto_ops;
	sk->protocol = protocol;

	init_timer(&rose->timer);
	init_timer(&rose->idletimer);

	rose->t1   = sysctl_rose_call_request_timeout;
	rose->t2   = sysctl_rose_reset_request_timeout;
	rose->t3   = sysctl_rose_clear_request_timeout;
	rose->hb   = sysctl_rose_ack_hold_back_timeout;
	rose->idle = sysctl_rose_no_activity_timeout;

	rose->state = ROSE_STATE_0;

	return 0;
}

static struct sock *rose_make_new(struct sock *osk)
{
	struct sock *sk;
	rose_cb *rose;

	if (osk->type != SOCK_SEQPACKET)
		return NULL;

	if ((sk = rose_alloc_sock()) == NULL)
		return NULL;

	rose = sk->protinfo.rose;

	sock_init_data(NULL, sk);

	skb_queue_head_init(&rose->ack_queue);
#ifdef M_BIT
	skb_queue_head_init(&rose->frag_queue);
	rose->fraglen  = 0;
#endif

	sk->type     = osk->type;
	sk->socket   = osk->socket;
	sk->priority = osk->priority;
	sk->protocol = osk->protocol;
	sk->rcvbuf   = osk->rcvbuf;
	sk->sndbuf   = osk->sndbuf;
	sk->debug    = osk->debug;
	sk->state    = TCP_ESTABLISHED;
	sk->sleep    = osk->sleep;
	sk->zapped   = osk->zapped;

	init_timer(&rose->timer);
	init_timer(&rose->idletimer);

	rose->t1      = osk->protinfo.rose->t1;
	rose->t2      = osk->protinfo.rose->t2;
	rose->t3      = osk->protinfo.rose->t3;
	rose->hb      = osk->protinfo.rose->hb;
	rose->idle    = osk->protinfo.rose->idle;

	rose->defer    = osk->protinfo.rose->defer;
	rose->device   = osk->protinfo.rose->device;
	rose->qbitincl = osk->protinfo.rose->qbitincl;

	return sk;
}

static int rose_release(struct socket *sock)
{
	struct sock *sk = sock->sk;

	if (sk == NULL) return 0;

	switch (sk->protinfo.rose->state) {

		case ROSE_STATE_0:
			rose_disconnect(sk, 0, -1, -1);
			rose_destroy_socket(sk);
			break;

		case ROSE_STATE_2:
			sk->protinfo.rose->neighbour->use--;
			rose_disconnect(sk, 0, -1, -1);
			rose_destroy_socket(sk);
			break;

		case ROSE_STATE_1:
		case ROSE_STATE_3:
		case ROSE_STATE_4:
		case ROSE_STATE_5:
			rose_clear_queues(sk);
			rose_stop_idletimer(sk);
			rose_write_internal(sk, ROSE_CLEAR_REQUEST);
			rose_start_t3timer(sk);
			sk->protinfo.rose->state = ROSE_STATE_2;
			sk->state                = TCP_CLOSE;
			sk->shutdown            |= SEND_SHUTDOWN;
			sk->state_change(sk);
			sk->dead                 = 1;
			sk->destroy              = 1;
			break;

		default:
			break;
	}

	sock->sk = NULL;	
	sk->socket = NULL;	/* Not used, but we should do this. **/

	return 0;
}

static int rose_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
	struct sock *sk = sock->sk;
	struct sockaddr_rose *addr = (struct sockaddr_rose *)uaddr;
	struct net_device *dev;
	ax25_address *user, *source;
	int n;

	if (sk->zapped == 0)
		return -EINVAL;

	if (addr_len != sizeof(struct sockaddr_rose) && addr_len != sizeof(struct full_sockaddr_rose))
		return -EINVAL;

	if (addr->srose_family != AF_ROSE)
		return -EINVAL;

	if (addr_len == sizeof(struct sockaddr_rose) && addr->srose_ndigis > 1)
		return -EINVAL;

	if (addr->srose_ndigis > ROSE_MAX_DIGIS)
		return -EINVAL;

	if ((dev = rose_dev_get(&addr->srose_addr)) == NULL) {
		SOCK_DEBUG(sk, "ROSE: bind failed: invalid address\n");
		return -EADDRNOTAVAIL;
	}

	source = &addr->srose_call;

	if ((user = ax25_findbyuid(current->euid)) == NULL) {
		if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE))
			return -EACCES;
		user = source;
	}

	sk->protinfo.rose->source_addr   = addr->srose_addr;
	sk->protinfo.rose->source_call   = *user;
	sk->protinfo.rose->device        = dev;
	sk->protinfo.rose->source_ndigis = addr->srose_ndigis;

	if (addr_len == sizeof(struct full_sockaddr_rose)) {
		struct full_sockaddr_rose *full_addr = (struct full_sockaddr_rose *)uaddr;
		for (n = 0 ; n < addr->srose_ndigis ; n++)
			sk->protinfo.rose->source_digis[n] = full_addr->srose_digis[n];
	} else {
		if (sk->protinfo.rose->source_ndigis == 1) {
			sk->protinfo.rose->source_digis[0] = addr->srose_digi;
		}
	}

	rose_insert_socket(sk);

	sk->zapped = 0;
	SOCK_DEBUG(sk, "ROSE: socket is bound\n");
	return 0;
}

static int rose_connect(struct socket *sock, struct sockaddr *uaddr, int addr_len, int flags)
{
	struct sock *sk = sock->sk;
	struct sockaddr_rose *addr = (struct sockaddr_rose *)uaddr;
	unsigned char cause, diagnostic;
	ax25_address *user;
	struct net_device *dev;
	int n;

	if (sk->state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
		sock->state = SS_CONNECTED;
		return 0;	/* Connect completed during a ERESTARTSYS event */
	}

	if (sk->state == TCP_CLOSE && sock->state == SS_CONNECTING) {
		sock->state = SS_UNCONNECTED;
		return -ECONNREFUSED;
	}

	if (sk->state == TCP_ESTABLISHED)
		return -EISCONN;	/* No reconnect on a seqpacket socket */

	sk->state   = TCP_CLOSE;
	sock->state = SS_UNCONNECTED;

	if (addr_len != sizeof(struct sockaddr_rose) && addr_len != sizeof(struct full_sockaddr_rose))
		return -EINVAL;

	if (addr->srose_family != AF_ROSE)
		return -EINVAL;

	if (addr_len == sizeof(struct sockaddr_rose) && addr->srose_ndigis > 1)
		return -EINVAL;

	if (addr->srose_ndigis > ROSE_MAX_DIGIS)
		return -EINVAL;

	/* Source + Destination digis should not exceed ROSE_MAX_DIGIS */
	if ((sk->protinfo.rose->source_ndigis + addr->srose_ndigis) > ROSE_MAX_DIGIS)
		return -EINVAL;

	if ((sk->protinfo.rose->neighbour = rose_get_neigh(&addr->srose_addr, &cause, &diagnostic)) == NULL)
		return -ENETUNREACH;

	if ((sk->protinfo.rose->lci = rose_new_lci(sk->protinfo.rose->neighbour)) == 0)
		return -ENETUNREACH;

	if (sk->zapped) {	/* Must bind first - autobinding in this may or may not work */
		sk->zapped = 0;

		if ((dev = rose_dev_first()) == NULL)
			return -ENETUNREACH;

		if ((user = ax25_findbyuid(current->euid)) == NULL)
			return -EINVAL;

		memcpy(&sk->protinfo.rose->source_addr, dev->dev_addr, ROSE_ADDR_LEN);
		sk->protinfo.rose->source_call = *user;
		sk->protinfo.rose->device      = dev;

		rose_insert_socket(sk);		/* Finish the bind */
	}

	sk->protinfo.rose->dest_addr   = addr->srose_addr;
	sk->protinfo.rose->dest_call   = addr->srose_call;
	sk->protinfo.rose->rand        = ((int)sk->protinfo.rose & 0xFFFF) + sk->protinfo.rose->lci;
	sk->protinfo.rose->dest_ndigis = addr->srose_ndigis;

	if (addr_len == sizeof(struct full_sockaddr_rose)) {
		struct full_sockaddr_rose *full_addr = (struct full_sockaddr_rose *)uaddr;
		for (n = 0 ; n < addr->srose_ndigis ; n++)
			sk->protinfo.rose->dest_digis[n] = full_addr->srose_digis[n];
	} else {
		if (sk->protinfo.rose->dest_ndigis == 1) {
			sk->protinfo.rose->dest_digis[0] = addr->srose_digi;
		}
	}

	/* Move to connecting socket, start sending Connect Requests */
	sock->state   = SS_CONNECTING;
	sk->state     = TCP_SYN_SENT;

	sk->protinfo.rose->state = ROSE_STATE_1;

	sk->protinfo.rose->neighbour->use++;

	rose_write_internal(sk, ROSE_CALL_REQUEST);
	rose_start_heartbeat(sk);
	rose_start_t1timer(sk);

	/* Now the loop */
	if (sk->state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
		return -EINPROGRESS;

	cli();	/* To avoid races on the sleep */

	/*
	 * A Connect Ack with Choke or timeout or failed routing will go to closed.
	 */
	while (sk->state == TCP_SYN_SENT) {
		interruptible_sleep_on(sk->sleep);
		if (signal_pending(current)) {
			sti();
			return -ERESTARTSYS;
		}
	}

	if (sk->state != TCP_ESTABLISHED) {
		sti();
		sock->state = SS_UNCONNECTED;
		return sock_error(sk);	/* Always set at this point */
	}

	sock->state = SS_CONNECTED;

	sti();

	return 0;
}

static int rose_accept(struct socket *sock, struct socket *newsock, int flags)
{
	struct sock *sk;
	struct sock *newsk;
	struct sk_buff *skb;

	if ((sk = sock->sk) == NULL)
		return -EINVAL;

	if (sk->type != SOCK_SEQPACKET)
		return -EOPNOTSUPP;

	if (sk->state != TCP_LISTEN)
		return -EINVAL;

	/*
	 *	The write queue this time is holding sockets ready to use
	 *	hooked into the SABM we saved
	 */
	do {
		cli();
		if ((skb = skb_dequeue(&sk->receive_queue)) == NULL) {
			if (flags & O_NONBLOCK) {
				sti();
				return -EWOULDBLOCK;
			}
			interruptible_sleep_on(sk->sleep);
			if (signal_pending(current)) {
				sti();
				return -ERESTARTSYS;
			}
		}
	} while (skb == NULL);

	newsk = skb->sk;
	newsk->pair = NULL;
	newsk->socket = newsock;
	newsk->sleep = &newsock->wait;
	sti();

	/* Now attach up the new socket */
	skb->sk = NULL;
	kfree_skb(skb);
	sk->ack_backlog--;
	newsock->sk = newsk;

	return 0;
}

static int rose_getname(struct socket *sock, struct sockaddr *uaddr,
	int *uaddr_len, int peer)
{
	struct full_sockaddr_rose *srose = (struct full_sockaddr_rose *)uaddr;
	struct sock *sk = sock->sk;
	int n;

	if (peer != 0) {
		if (sk->state != TCP_ESTABLISHED)
			return -ENOTCONN;
		srose->srose_family = AF_ROSE;
		srose->srose_addr   = sk->protinfo.rose->dest_addr;
		srose->srose_call   = sk->protinfo.rose->dest_call;
		srose->srose_ndigis = sk->protinfo.rose->dest_ndigis;
		for (n = 0 ; n < sk->protinfo.rose->dest_ndigis ; n++)
			srose->srose_digis[n] = sk->protinfo.rose->dest_digis[n];
	} else {
		srose->srose_family = AF_ROSE;
		srose->srose_addr   = sk->protinfo.rose->source_addr;
		srose->srose_call   = sk->protinfo.rose->source_call;
		srose->srose_ndigis = sk->protinfo.rose->source_ndigis;
		for (n = 0 ; n < sk->protinfo.rose->source_ndigis ; n++)
			srose->srose_digis[n] = sk->protinfo.rose->source_digis[n];
	}

	*uaddr_len = sizeof(struct full_sockaddr_rose);
	return 0;
}

int rose_rx_call_request(struct sk_buff *skb, struct net_device *dev, struct rose_neigh *neigh, unsigned int lci)
{
	struct sock *sk;
	struct sock *make;
	struct rose_facilities_struct facilities;
	int n, len;

	skb->sk = NULL;		/* Initially we don't know who it's for */

	/*
	 *	skb->data points to the rose frame start
	 */
	memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
	
	len  = (((skb->data[3] >> 4) & 0x0F) + 1) / 2;
	len += (((skb->data[3] >> 0) & 0x0F) + 1) / 2;
	if (!rose_parse_facilities(skb->data + len + 4, &facilities)) {
		rose_transmit_clear_request(neigh, lci, ROSE_INVALID_FACILITY, 76);
		return 0;
	}

	sk = rose_find_listener(&facilities.source_addr, &facilities.source_call);

	/*
	 * We can't accept the Call Request.
	 */
	if (sk == NULL || sk->ack_backlog == sk->max_ack_backlog || (make = rose_make_new(sk)) == NULL) {
		rose_transmit_clear_request(neigh, lci, ROSE_NETWORK_CONGESTION, 120);
		return 0;
	}

	skb->sk     = make;
	make->state = TCP_ESTABLISHED;

	make->protinfo.rose->lci           = lci;
	make->protinfo.rose->dest_addr     = facilities.dest_addr;
	make->protinfo.rose->dest_call     = facilities.dest_call;
	make->protinfo.rose->dest_ndigis   = facilities.dest_ndigis;
	for (n = 0 ; n < facilities.dest_ndigis ; n++)
		make->protinfo.rose->dest_digis[n] = facilities.dest_digis[n];
	make->protinfo.rose->source_addr   = facilities.source_addr;
	make->protinfo.rose->source_call   = facilities.source_call;
	make->protinfo.rose->source_ndigis = facilities.source_ndigis;
	for (n = 0 ; n < facilities.source_ndigis ; n++)
		make->protinfo.rose->source_digis[n]= facilities.source_digis[n];
	make->protinfo.rose->neighbour     = neigh;
	make->protinfo.rose->device        = dev;
	make->protinfo.rose->facilities    = facilities;

	make->protinfo.rose->neighbour->use++;

	if (sk->protinfo.rose->defer) {
		make->protinfo.rose->state = ROSE_STATE_5;
	} else {
		rose_write_internal(make, ROSE_CALL_ACCEPTED);
		make->protinfo.rose->state = ROSE_STATE_3;
		rose_start_idletimer(make);
	}

	make->protinfo.rose->condition = 0x00;
	make->protinfo.rose->vs        = 0;
	make->protinfo.rose->va        = 0;
	make->protinfo.rose->vr        = 0;
	make->protinfo.rose->vl        = 0;
	sk->ack_backlog++;
	make->pair = sk;

	rose_insert_socket(make);

	skb_queue_head(&sk->receive_queue, skb);

	rose_start_heartbeat(make);

	if (!sk->dead)
		sk->data_ready(sk, skb->len);

	return 1;
}

static int rose_sendmsg(struct socket *sock, struct msghdr *msg, int len, 
				struct scm_cookie *scm)
{
	struct sock *sk = sock->sk;
	struct sockaddr_rose *usrose = (struct sockaddr_rose *)msg->msg_name;
	int err;
	struct full_sockaddr_rose srose;
	struct sk_buff *skb;
	unsigned char *asmptr;
	int n, size, qbit = 0;

	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR))
		return -EINVAL;