af_rose.c

linux 内核源代码

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

	sk = sk_alloc(osk->sk_net, PF_ROSE, GFP_ATOMIC, &rose_proto);
	if (sk == NULL)
		return NULL;

	rose = rose_sk(sk);

	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->sk_type     = osk->sk_type;
	sk->sk_socket   = osk->sk_socket;
	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_sleep    = osk->sk_sleep;
	sock_copy_flags(sk, osk);

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

	orose		= rose_sk(osk);
	rose->t1	= orose->t1;
	rose->t2	= orose->t2;
	rose->t3	= orose->t3;
	rose->hb	= orose->hb;
	rose->idle	= orose->idle;
	rose->defer	= orose->defer;
	rose->device	= orose->device;
	rose->qbitincl	= orose->qbitincl;

	return sk;
}

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

	if (sk == NULL) return 0;

	rose = rose_sk(sk);

	switch (rose->state) {
	case ROSE_STATE_0:
		rose_disconnect(sk, 0, -1, -1);
		rose_destroy_socket(sk);
		break;

	case ROSE_STATE_2:
		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);
		rose->state  = ROSE_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;

	default:
		break;
	}

	sock->sk = NULL;

	return 0;
}

static int rose_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
	struct sock *sk = sock->sk;
	struct rose_sock *rose = rose_sk(sk);
	struct sockaddr_rose *addr = (struct sockaddr_rose *)uaddr;
	struct net_device *dev;
	ax25_address *source;
	ax25_uid_assoc *user;
	int n;

	if (!sock_flag(sk, SOCK_ZAPPED))
		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;

	user = ax25_findbyuid(current->euid);
	if (user) {
		rose->source_call = user->call;
		ax25_uid_put(user);
	} else {
		if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE))
			return -EACCES;
		rose->source_call   = *source;
	}

	rose->source_addr   = addr->srose_addr;
	rose->device        = dev;
	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++)
			rose->source_digis[n] = full_addr->srose_digis[n];
	} else {
		if (rose->source_ndigis == 1) {
			rose->source_digis[0] = addr->srose_digi;
		}
	}

	rose_insert_socket(sk);

	sock_reset_flag(sk, SOCK_ZAPPED);
	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 rose_sock *rose = rose_sk(sk);
	struct sockaddr_rose *addr = (struct sockaddr_rose *)uaddr;
	unsigned char cause, diagnostic;
	struct net_device *dev;
	ax25_uid_assoc *user;
	int n, err = 0;

	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 ((rose->source_ndigis + addr->srose_ndigis) > ROSE_MAX_DIGIS)
		return -EINVAL;

	lock_sock(sk);

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

	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
		sock->state = SS_UNCONNECTED;
		err = -ECONNREFUSED;
		goto out_release;
	}

	if (sk->sk_state == TCP_ESTABLISHED) {
		/* No reconnect on a seqpacket socket */
		err = -EISCONN;
		goto out_release;
	}

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

	rose->neighbour = rose_get_neigh(&addr->srose_addr, &cause,
					 &diagnostic);
	if (!rose->neighbour)
		return -ENETUNREACH;

	rose->lci = rose_new_lci(rose->neighbour);
	if (!rose->lci) {
		err = -ENETUNREACH;
		goto out_release;
	}

	if (sock_flag(sk, SOCK_ZAPPED)) {	/* Must bind first - autobinding in this may or may not work */
		sock_reset_flag(sk, SOCK_ZAPPED);

		if ((dev = rose_dev_first()) == NULL) {
			err = -ENETUNREACH;
			goto out_release;
		}

		user = ax25_findbyuid(current->euid);
		if (!user) {
			err = -EINVAL;
			goto out_release;
		}

		memcpy(&rose->source_addr, dev->dev_addr, ROSE_ADDR_LEN);
		rose->source_call = user->call;
		rose->device      = dev;
		ax25_uid_put(user);

		rose_insert_socket(sk);		/* Finish the bind */
	}
rose_try_next_neigh:
	rose->dest_addr   = addr->srose_addr;
	rose->dest_call   = addr->srose_call;
	rose->rand        = ((long)rose & 0xFFFF) + rose->lci;
	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++)
			rose->dest_digis[n] = full_addr->srose_digis[n];
	} else {
		if (rose->dest_ndigis == 1) {
			rose->dest_digis[0] = addr->srose_digi;
		}
	}

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

	rose->state = ROSE_STATE_1;

	rose->neighbour->use++;

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

	/* Now the loop */
	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
		err = -EINPROGRESS;
		goto out_release;
	}

	/*
	 * A Connect Ack with Choke or timeout or failed routing will go to
	 * closed.
	 */
	if (sk->sk_state == TCP_SYN_SENT) {
		DEFINE_WAIT(wait);

		for (;;) {
			prepare_to_wait(sk->sk_sleep, &wait,
					TASK_INTERRUPTIBLE);
			if (sk->sk_state != TCP_SYN_SENT)
				break;
			if (!signal_pending(current)) {
				release_sock(sk);
				schedule();
				lock_sock(sk);
				continue;
			}
			err = -ERESTARTSYS;
			break;
		}
		finish_wait(sk->sk_sleep, &wait);

		if (err)
			goto out_release;
	}

	if (sk->sk_state != TCP_ESTABLISHED) {
	/* Try next neighbour */
		rose->neighbour = rose_get_neigh(&addr->srose_addr, &cause, &diagnostic);
		if (rose->neighbour)
			goto rose_try_next_neigh;

		/* No more neighbours */
		sock->state = SS_UNCONNECTED;
		err = sock_error(sk);	/* Always set at this point */
		goto out_release;
	}

	sock->state = SS_CONNECTED;

out_release:
	release_sock(sk);

	return err;
}

static int rose_accept(struct socket *sock, struct socket *newsock, int flags)
{
	struct sk_buff *skb;
	struct sock *newsk;
	DEFINE_WAIT(wait);
	struct sock *sk;
	int err = 0;

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

	lock_sock(sk);
	if (sk->sk_type != SOCK_SEQPACKET) {
		err = -EOPNOTSUPP;
		goto out_release;
	}

	if (sk->sk_state != TCP_LISTEN) {
		err = -EINVAL;
		goto out_release;
	}

	/*
	 *	The write queue this time is holding sockets ready to use
	 *	hooked into the SABM we saved
	 */
	for (;;) {
		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);

		skb = skb_dequeue(&sk->sk_receive_queue);
		if (skb)
			break;

		if (flags & O_NONBLOCK) {
			err = -EWOULDBLOCK;
			break;
		}
		if (!signal_pending(current)) {
			release_sock(sk);
			schedule();
			lock_sock(sk);
			continue;
		}
		err = -ERESTARTSYS;
		break;
	}
	finish_wait(sk->sk_sleep, &wait);
	if (err)
		goto out_release;

	newsk = skb->sk;
	newsk->sk_socket = newsock;
	newsk->sk_sleep = &newsock->wait;

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

out_release:
	release_sock(sk);

	return err;
}

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;
	struct rose_sock *rose = rose_sk(sk);
	int n;

	if (peer != 0) {
		if (sk->sk_state != TCP_ESTABLISHED)
			return -ENOTCONN;
		srose->srose_family = AF_ROSE;
		srose->srose_addr   = rose->dest_addr;
		srose->srose_call   = rose->dest_call;
		srose->srose_ndigis = rose->dest_ndigis;
		for (n = 0; n < rose->dest_ndigis; n++)
			srose->srose_digis[n] = rose->dest_digis[n];
	} else {
		srose->srose_family = AF_ROSE;
		srose->srose_addr   = rose->source_addr;
		srose->srose_call   = rose->source_call;
		srose->srose_ndigis = rose->source_ndigis;
		for (n = 0; n < rose->source_ndigis; n++)
			srose->srose_digis[n] = 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_sock *make_rose;
	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_acceptq_is_full(sk) ||
	    (make = rose_make_new(sk)) == NULL) {
		rose_transmit_clear_request(neigh, lci, ROSE_NETWORK_CONGESTION, 120);
		return 0;
	}

	skb->sk     = make;
	make->sk_state = TCP_ESTABLISHED;
	make_rose = rose_sk(make);

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

	make_rose->neighbour->use++;

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

	make_rose->condition = 0x00;
	make_rose->vs        = 0;
	make_rose->va        = 0;
	make_rose->vr        = 0;
	make_rose->vl        = 0;
	sk->sk_ack_backlog++;

	rose_insert_socket(make);

	skb_queue_head(&sk->sk_receive_queue, skb);

	rose_start_heartbeat(make);

	if (!sock_flag(sk, SOCK_DEAD))
		sk->sk_data_ready(sk, skb->len);

	return 1;
}

static int rose_sendmsg(struct kiocb *iocb, struct socket *sock,
			struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
	struct rose_sock *rose = rose_sk(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|MSG_CMSG_COMPAT))
		return -EINVAL;

	if (sock_flag(sk, SOCK_ZAPPED))
		return -EADDRNOTAVAIL;

	if (sk->sk_shutdown & SEND_SHUTDOWN) {
		send_sig(SIGPIPE, current, 0);
		return -EPIPE;
	}

	if (rose->neighbour == NULL || rose->device == NULL)
		return -ENETUNREACH;

	if (usrose != NULL) {
		if (msg->msg_namelen != sizeof(struct sockaddr_rose) && msg->msg_namelen != sizeof(struct full_sockaddr_rose))
			return -EINVAL;
		memset(&srose, 0, sizeof(struct full_sockaddr_rose));
		memcpy(&srose, usrose, msg->msg_namelen);
		if (rosecmp(&rose->dest_addr, &srose.srose_addr) != 0 ||
		    ax25cmp(&rose->dest_call, &srose.srose_call) != 0)
			return -EISCONN;
		if (srose.srose_ndigis != rose->dest_ndigis)
			return -EISCONN;
		if (srose.srose_ndigis == rose->dest_ndigis) {
			for (n = 0 ; n < srose.srose_ndigis ; n++)
				if (ax25cmp(&rose->dest_digis[n],
					    &srose.srose_digis[n]))
					return -EISCONN;
		}
		if (srose.srose_family != AF_ROSE)
			return -EINVAL;
	} else {
		if (sk->sk_state != TCP_ESTABLISHED)
			return -ENOTCONN;

		srose.srose_family = AF_ROSE;
		srose.srose_addr   = rose->dest_addr;
		srose.srose_call   = rose->dest_call;
		srose.srose_ndigis = rose->dest_ndigis;
		for (n = 0 ; n < rose->dest_ndigis ; n++)
			srose.srose_digis[n] = rose->dest_digis[n];
	}

	SOCK_DEBUG(sk, "ROSE: sendto: Addresses built.\n");

	/* Build a packet */
	SOCK_DEBUG(sk, "ROSE: sendto: building packet.\n");