af_decnet.c

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	switch(scp->state) {
		case DN_DN:
			dn_nsp_send_disc(sk, NSP_DISCCONF, NSP_REASON_DC, sk->allocation);
			scp->persist_fxn = dn_destroy_timer;
			scp->persist = dn_nsp_persist(sk);
			break;
		case DN_CR:
			scp->state = DN_DR;
			goto disc_reject;
		case DN_RUN:
			scp->state = DN_DI;
		case DN_DI:
		case DN_DR:
disc_reject:
			dn_nsp_send_disc(sk, NSP_DISCINIT, 0, sk->allocation);
		case DN_NC:
		case DN_NR:
		case DN_RJ:
		case DN_DIC:
		case DN_CN:
		case DN_DRC:
		case DN_CI:
		case DN_CD:
			scp->persist_fxn = dn_destroy_timer;
			scp->persist = dn_nsp_persist(sk);
			break;
		default:
			printk(KERN_DEBUG "DECnet: dn_destroy_sock passed socket in invalid state\n");
		case DN_O:
			dn_stop_fast_timer(sk);
			dn_stop_slow_timer(sk);

			dn_unhash_sock_bh(sk);
			sock_put(sk);

			break;
	}
}

char *dn_addr2asc(dn_address addr, char *buf)
{
	unsigned short node, area;

	node = addr & 0x03ff;
	area = addr >> 10;
	sprintf(buf, "%hd.%hd", area, node);

	return buf;
}


static char *dn_state2asc(unsigned char state)
{
	switch(state) {
		case DN_O:
			return "OPEN";
		case DN_CR:
			return "  CR";
		case DN_DR:
			return "  DR";
		case DN_DRC:
			return " DRC";
		case DN_CC:
			return "  CC";
		case DN_CI:
			return "  CI";
		case DN_NR:
			return "  NR";
		case DN_NC:
			return "  NC";
		case DN_CD:
			return "  CD";
		case DN_RJ:
			return "  RJ";
		case DN_RUN:
			return " RUN";
		case DN_DI:
			return "  DI";
		case DN_DIC:
			return " DIC";
		case DN_DN:
			return "  DN";
		case DN_CL:
			return "  CL";
		case DN_CN:
			return "  CN";
	}

	return "????";
}

static int dn_create(struct socket *sock, int protocol)
{
	struct sock *sk;

	switch(sock->type) {
		case SOCK_SEQPACKET:
			if (protocol != DNPROTO_NSP)
				return -EPROTONOSUPPORT;
			break;
		case SOCK_STREAM:
			break;
		default:
			return -ESOCKTNOSUPPORT;
	}


	if ((sk = dn_alloc_sock(sock, GFP_KERNEL)) == NULL) 
		return -ENOBUFS;

	sk->protocol = protocol;

	return 0;
}


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

	if (sk) {
		sock_orphan(sk);
		sock_hold(sk);
		lock_sock(sk);
		dn_destroy_sock(sk);
		release_sock(sk);
		sock_put(sk);
	}

        return 0;
}

static int dn_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
	struct sock *sk = sock->sk;
	struct dn_scp *scp = &sk->protinfo.dn;
	struct sockaddr_dn *saddr = (struct sockaddr_dn *)uaddr;
	struct net_device *dev;
	int rv;

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

	if (addr_len != sizeof(struct sockaddr_dn))
		return -EINVAL;

	if (saddr->sdn_family != AF_DECnet)
		return -EINVAL;

	if (dn_ntohs(saddr->sdn_nodeaddrl) && (dn_ntohs(saddr->sdn_nodeaddrl) != 2))
		return -EINVAL;

	if (saddr->sdn_objnum && !capable(CAP_NET_BIND_SERVICE))
		return -EPERM;

	if (dn_ntohs(saddr->sdn_objnamel) > DN_MAXOBJL)
		return -EINVAL;

	if (saddr->sdn_flags & ~SDF_WILD)
		return -EINVAL;

	if (saddr->sdn_flags & SDF_WILD) {
		if (!capable(CAP_NET_BIND_SERVICE))
			return -EPERM;
	} else {
		if (dn_ntohs(saddr->sdn_nodeaddrl)) {
			read_lock(&dev_base_lock);
			for(dev = dev_base; dev; dev = dev->next) {
				if (!dev->dn_ptr)
					continue;
				if (dn_dev_islocal(dev, dn_saddr2dn(saddr)))
					break;
			}
			read_unlock(&dev_base_lock);
			if (dev == NULL)
				return -EADDRNOTAVAIL;
		}
	}


	memcpy(&scp->addr, saddr, addr_len);
	sk->zapped = 0;

	if ((rv = dn_hash_sock(sk)) == 0)
		goto out;

	sk->zapped = 1;
out:

        return rv;
}


static int dn_auto_bind(struct socket *sock)
{
	struct sock *sk = sock->sk;
	struct dn_scp *scp = &sk->protinfo.dn;

	sk->zapped = 0;

	scp->addr.sdn_flags  = 0;
	scp->addr.sdn_objnum = 0;

	/*
	 * This stuff is to keep compatibility with Eduardo's
	 * patch. I hope I can dispense with it shortly...
	 */
	if ((scp->accessdata.acc_accl != 0) &&
		(scp->accessdata.acc_accl <= 12)) {
	
		scp->addr.sdn_objnamel = dn_htons(scp->accessdata.acc_accl);
		memcpy(scp->addr.sdn_objname, scp->accessdata.acc_acc, dn_ntohs(scp->addr.sdn_objnamel));

		scp->accessdata.acc_accl = 0;
		memset(scp->accessdata.acc_acc, 0, 40);
	}

	scp->addr.sdn_add.a_len = dn_htons(2);
	*(dn_address *)scp->addr.sdn_add.a_addr = decnet_address;

	dn_hash_sock(sk);

	return 0;
}


static int dn_connect(struct socket *sock, struct sockaddr *uaddr, int addr_len, int flags)
{
	struct sockaddr_dn *addr = (struct sockaddr_dn *)uaddr;
	struct sock *sk = sock->sk;
	struct dn_scp *scp = &sk->protinfo.dn;
	int err = -EISCONN;

	lock_sock(sk);

	if (sock->state == SS_CONNECTED) 
		goto out;

	if (sock->state == SS_CONNECTING) {
		err = 0;
		if (sk->state == TCP_ESTABLISHED)
			goto out;

		err = -ECONNREFUSED;
		if (sk->state == TCP_CLOSE)
			goto out;
	}

	err = -EINVAL;
	if (sk->protinfo.dn.state != DN_O)
		goto out;

	if (addr_len != sizeof(struct sockaddr_dn))
		goto out;

	if (addr->sdn_family != AF_DECnet)
		goto out;

	if (addr->sdn_flags & SDF_WILD)
		goto out;

	err = -EADDRNOTAVAIL;
	if (sk->zapped && (err = dn_auto_bind(sock)))
		goto out;

	memcpy(&scp->peer, addr, addr_len);

	err = -EHOSTUNREACH;
	if (dn_route_output(&sk->dst_cache, dn_saddr2dn(&scp->peer), dn_saddr2dn(&scp->addr), 0) < 0)
		goto out;

	sk->state   = TCP_SYN_SENT;
	sock->state = SS_CONNECTING;
	sk->protinfo.dn.state = DN_CI;

	dn_nsp_send_conninit(sk, NSP_CI);

	err = -EINPROGRESS;
	if ((sk->state == TCP_SYN_SENT) && (flags & O_NONBLOCK))
		goto out;

	while(sk->state == TCP_SYN_SENT) {

		err = -ERESTARTSYS;
		if (signal_pending(current))
			goto out;

		if ((err = sock_error(sk)) != 0) {
			sock->state = SS_UNCONNECTED;
			goto out;
		}

		SOCK_SLEEP_PRE(sk);

		if (sk->state == TCP_SYN_SENT)
			schedule();

		SOCK_SLEEP_POST(sk);
	}

	if (sk->state != TCP_ESTABLISHED) {
		sock->state = SS_UNCONNECTED;
		err = sock_error(sk);
		goto out;
	}

	err = 0;
	sock->state = SS_CONNECTED;
out:
	release_sock(sk);

        return err;
}

static int dn_access_copy(struct sk_buff *skb, struct accessdata_dn *acc)
{
        unsigned char *ptr = skb->data;

        acc->acc_userl = *ptr++;
        memcpy(&acc->acc_user, ptr, acc->acc_userl);
        ptr += acc->acc_userl;

        acc->acc_passl = *ptr++;
        memcpy(&acc->acc_pass, ptr, acc->acc_passl);
        ptr += acc->acc_passl;

        acc->acc_accl = *ptr++;
        memcpy(&acc->acc_acc, ptr, acc->acc_accl);

        skb_pull(skb, acc->acc_accl + acc->acc_passl + acc->acc_userl + 3);

	return 0;
}

static int dn_user_copy(struct sk_buff *skb, struct optdata_dn *opt)
{
        unsigned char *ptr = skb->data;
        
        opt->opt_optl   = *ptr++;
        opt->opt_status = 0;
        memcpy(opt->opt_data, ptr, opt->opt_optl);
        skb_pull(skb, opt->opt_optl + 1);

	return 0;
}


/*
 * This is here for use in the sockopt() call as well as
 * in accept(). Must be called with a locked socket.
 */
static int dn_wait_accept(struct socket *sock, int flags)
{
        struct sock *sk = sock->sk;

        while(sk->state == TCP_LISTEN) {
                if (flags & O_NONBLOCK) {
                        return -EAGAIN;
                }

		SOCK_SLEEP_PRE(sk)

		if (sk->state == TCP_LISTEN)
			schedule();

		SOCK_SLEEP_POST(sk)

                if (signal_pending(current))
                        return -ERESTARTSYS; /* But of course you don't! */
        }

        if ((sk->protinfo.dn.state != DN_RUN) && (sk->protinfo.dn.state != DN_DRC)) {
                sock->state = SS_UNCONNECTED;
                return sock_error(sk);
        }

	sock->state = SS_CONNECTED;

        return 0;
}


static int dn_accept(struct socket *sock, struct socket *newsock, int flags)
{
	struct sock *sk = sock->sk, *newsk;
	struct sk_buff *skb = NULL;
	struct dn_skb_cb *cb;
	unsigned char menuver;
	int err = 0;
	unsigned char type;

	lock_sock(sk);

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

	if (sk->protinfo.dn.state != DN_O) {
		release_sock(sk);
		return -EINVAL;
	}

        do
        {
                if ((skb = skb_dequeue(&sk->receive_queue)) == NULL)
                {
                        if (flags & O_NONBLOCK)
                        {
                                release_sock(sk);
                                return -EAGAIN;
                        }

			SOCK_SLEEP_PRE(sk);

			if (!skb_peek(&sk->receive_queue))
				schedule();

			SOCK_SLEEP_POST(sk);

                        if (signal_pending(current))
                        {
				release_sock(sk);
                                return -ERESTARTSYS;
                        }
                }
        } while (skb == NULL);

	cb = (struct dn_skb_cb *)skb->cb;

	if ((newsk = dn_alloc_sock(newsock, sk->allocation)) == NULL) {
		release_sock(sk);
		kfree_skb(skb);
		return -ENOBUFS;
	}
	sk->ack_backlog--;
	release_sock(sk);

	dst_release(xchg(&newsk->dst_cache, skb->dst));
	skb->dst = NULL;

        newsk->protinfo.dn.state      = DN_CR;
	newsk->protinfo.dn.addrrem    = cb->src_port;
	newsk->protinfo.dn.mss        = cb->segsize;
	newsk->protinfo.dn.accept_mode = sk->protinfo.dn.accept_mode;
	
	if (newsk->protinfo.dn.mss < 230)
		newsk->protinfo.dn.mss = 230;

	newsk->state  = TCP_LISTEN;
	newsk->zapped = 0;

	memcpy(&newsk->protinfo.dn.addr, &sk->protinfo.dn.addr, sizeof(struct sockaddr_dn));

	/*
	 * If we are listening on a wild socket, we don't want
	 * the newly created socket on the wrong hash queue.
	 */
	newsk->protinfo.dn.addr.sdn_flags &= ~SDF_WILD;

	skb_pull(skb, dn_username2sockaddr(skb->data, skb->len, &newsk->protinfo.dn.addr, &type));
	skb_pull(skb, dn_username2sockaddr(skb->data, skb->len, &newsk->protinfo.dn.peer, &type));
	*(dn_address *)newsk->protinfo.dn.peer.sdn_add.a_addr = cb->src;
	*(dn_address *)newsk->protinfo.dn.addr.sdn_add.a_addr = cb->dst;

	menuver = *skb->data;
	skb_pull(skb, 1);

	if (menuver & DN_MENUVER_ACC)
		dn_access_copy(skb, &newsk->protinfo.dn.accessdata);

	if (menuver & DN_MENUVER_USR)
		dn_user_copy(skb, &newsk->protinfo.dn.conndata_in);

	if (menuver & DN_MENUVER_PRX)
		newsk->protinfo.dn.peer.sdn_flags |= SDF_PROXY;

	if (menuver & DN_MENUVER_UIC)
		newsk->protinfo.dn.peer.sdn_flags |= SDF_UICPROXY;

	kfree_skb(skb);

	memcpy(&newsk->protinfo.dn.conndata_out, &sk->protinfo.dn.conndata_out,
		sizeof(struct optdata_dn));
	memcpy(&newsk->protinfo.dn.discdata_out, &sk->protinfo.dn.discdata_out,
		sizeof(struct optdata_dn));

	lock_sock(newsk);
	dn_hash_sock(newsk);

	dn_send_conn_ack(newsk);

	if (newsk->protinfo.dn.accept_mode == ACC_IMMED) {
		newsk->protinfo.dn.state = DN_CC;
        	dn_send_conn_conf(newsk, newsk->allocation);
		err = dn_wait_accept(newsock, flags);
	}

	release_sock(newsk);
        return err;
}


static int dn_getname(struct socket *sock, struct sockaddr *uaddr,int *uaddr_len,int peer)
{
	struct sockaddr_dn *sa = (struct sockaddr_dn *)uaddr;
	struct sock *sk = sock->sk;
	struct dn_scp *scp = &sk->protinfo.dn;

	*uaddr_len = sizeof(struct sockaddr_dn);

	lock_sock(sk);

	if (peer) {
		if (sock->state != SS_CONNECTED && scp->accept_mode == ACC_IMMED)
			return -ENOTCONN;

		memcpy(sa, &scp->peer, sizeof(struct sockaddr_dn));
	} else {
		memcpy(sa, &scp->addr, sizeof(struct sockaddr_dn));
	}

	release_sock(sk);

        return 0;
}


static unsigned int dn_poll(struct file *file, struct socket *sock, poll_table  *wait)
{
	struct sock *sk = sock->sk;
	struct dn_scp *scp = &sk->protinfo.dn;
	int mask = datagram_poll(file, sock, wait);

	if (skb_queue_len(&scp->other_receive_queue))
		mask |= POLLRDBAND;

	return mask;
}