af_decnet.c

linux 内核源代码

	struct sk_buff *skb;
	int val;

	switch(cmd)
	{
	case SIOCGIFADDR:
	case SIOCSIFADDR:
		return dn_dev_ioctl(cmd, (void __user *)arg);

	case SIOCATMARK:
		lock_sock(sk);
		val = !skb_queue_empty(&scp->other_receive_queue);
		if (scp->state != DN_RUN)
			val = -ENOTCONN;
		release_sock(sk);
		return val;

	case TIOCOUTQ:
		amount = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
		if (amount < 0)
			amount = 0;
		err = put_user(amount, (int __user *)arg);
		break;

	case TIOCINQ:
		lock_sock(sk);
		if ((skb = skb_peek(&scp->other_receive_queue)) != NULL) {
			amount = skb->len;
		} else {
			struct sk_buff *skb = sk->sk_receive_queue.next;
			for(;;) {
				if (skb ==
				    (struct sk_buff *)&sk->sk_receive_queue)
					break;
				amount += skb->len;
				skb = skb->next;
			}
		}
		release_sock(sk);
		err = put_user(amount, (int __user *)arg);
		break;

	default:
		err = -ENOIOCTLCMD;
		break;
	}

	return err;
}

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

	lock_sock(sk);

	if (sock_flag(sk, SOCK_ZAPPED))
		goto out;

	if ((DN_SK(sk)->state != DN_O) || (sk->sk_state == TCP_LISTEN))
		goto out;

	sk->sk_max_ack_backlog = backlog;
	sk->sk_ack_backlog     = 0;
	sk->sk_state           = TCP_LISTEN;
	err                 = 0;
	dn_rehash_sock(sk);

out:
	release_sock(sk);

	return err;
}


static int dn_shutdown(struct socket *sock, int how)
{
	struct sock *sk = sock->sk;
	struct dn_scp *scp = DN_SK(sk);
	int err = -ENOTCONN;

	lock_sock(sk);

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

	err = 0;
	if (sock->state == SS_DISCONNECTING)
		goto out;

	err = -EINVAL;
	if (scp->state == DN_O)
		goto out;

	if (how != SHUTDOWN_MASK)
		goto out;

	sk->sk_shutdown = how;
	dn_destroy_sock(sk);
	err = 0;

out:
	release_sock(sk);

	return err;
}

static int dn_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
{
	struct sock *sk = sock->sk;
	int err;

	lock_sock(sk);
	err = __dn_setsockopt(sock, level, optname, optval, optlen, 0);
	release_sock(sk);

	return err;
}

static int __dn_setsockopt(struct socket *sock, int level,int optname, char __user *optval, int optlen, int flags)
{
	struct	sock *sk = sock->sk;
	struct dn_scp *scp = DN_SK(sk);
	long timeo;
	union {
		struct optdata_dn opt;
		struct accessdata_dn acc;
		int mode;
		unsigned long win;
		int val;
		unsigned char services;
		unsigned char info;
	} u;
	int err;

	if (optlen && !optval)
		return -EINVAL;

	if (optlen > sizeof(u))
		return -EINVAL;

	if (copy_from_user(&u, optval, optlen))
		return -EFAULT;

	switch(optname) {
		case DSO_CONDATA:
			if (sock->state == SS_CONNECTED)
				return -EISCONN;
			if ((scp->state != DN_O) && (scp->state != DN_CR))
				return -EINVAL;

			if (optlen != sizeof(struct optdata_dn))
				return -EINVAL;

			if (dn_ntohs(u.opt.opt_optl) > 16)
				return -EINVAL;

			memcpy(&scp->conndata_out, &u.opt, optlen);
			break;

		case DSO_DISDATA:
			if (sock->state != SS_CONNECTED && scp->accept_mode == ACC_IMMED)
				return -ENOTCONN;

			if (optlen != sizeof(struct optdata_dn))
				return -EINVAL;

			if (dn_ntohs(u.opt.opt_optl) > 16)
				return -EINVAL;

			memcpy(&scp->discdata_out, &u.opt, optlen);
			break;

		case DSO_CONACCESS:
			if (sock->state == SS_CONNECTED)
				return -EISCONN;
			if (scp->state != DN_O)
				return -EINVAL;

			if (optlen != sizeof(struct accessdata_dn))
				return -EINVAL;

			if ((u.acc.acc_accl > DN_MAXACCL) ||
					(u.acc.acc_passl > DN_MAXACCL) ||
					(u.acc.acc_userl > DN_MAXACCL))
				return -EINVAL;

			memcpy(&scp->accessdata, &u.acc, optlen);
			break;

		case DSO_ACCEPTMODE:
			if (sock->state == SS_CONNECTED)
				return -EISCONN;
			if (scp->state != DN_O)
				return -EINVAL;

			if (optlen != sizeof(int))
				return -EINVAL;

			if ((u.mode != ACC_IMMED) && (u.mode != ACC_DEFER))
				return -EINVAL;

			scp->accept_mode = (unsigned char)u.mode;
			break;

		case DSO_CONACCEPT:

			if (scp->state != DN_CR)
				return -EINVAL;
			timeo = sock_rcvtimeo(sk, 0);
			err = dn_confirm_accept(sk, &timeo, sk->sk_allocation);
			return err;

		case DSO_CONREJECT:

			if (scp->state != DN_CR)
				return -EINVAL;

			scp->state = DN_DR;
			sk->sk_shutdown = SHUTDOWN_MASK;
			dn_nsp_send_disc(sk, 0x38, 0, sk->sk_allocation);
			break;

		default:
#ifdef CONFIG_NETFILTER
		return nf_setsockopt(sk, PF_DECnet, optname, optval, optlen);
#endif
		case DSO_LINKINFO:
		case DSO_STREAM:
		case DSO_SEQPACKET:
			return -ENOPROTOOPT;

		case DSO_MAXWINDOW:
			if (optlen != sizeof(unsigned long))
				return -EINVAL;
			if (u.win > NSP_MAX_WINDOW)
				u.win = NSP_MAX_WINDOW;
			if (u.win == 0)
				return -EINVAL;
			scp->max_window = u.win;
			if (scp->snd_window > u.win)
				scp->snd_window = u.win;
			break;

		case DSO_NODELAY:
			if (optlen != sizeof(int))
				return -EINVAL;
			if (scp->nonagle == 2)
				return -EINVAL;
			scp->nonagle = (u.val == 0) ? 0 : 1;
			/* if (scp->nonagle == 1) { Push pending frames } */
			break;

		case DSO_CORK:
			if (optlen != sizeof(int))
				return -EINVAL;
			if (scp->nonagle == 1)
				return -EINVAL;
			scp->nonagle = (u.val == 0) ? 0 : 2;
			/* if (scp->nonagle == 0) { Push pending frames } */
			break;

		case DSO_SERVICES:
			if (optlen != sizeof(unsigned char))
				return -EINVAL;
			if ((u.services & ~NSP_FC_MASK) != 0x01)
				return -EINVAL;
			if ((u.services & NSP_FC_MASK) == NSP_FC_MASK)
				return -EINVAL;
			scp->services_loc = u.services;
			break;

		case DSO_INFO:
			if (optlen != sizeof(unsigned char))
				return -EINVAL;
			if (u.info & 0xfc)
				return -EINVAL;
			scp->info_loc = u.info;
			break;
	}

	return 0;
}

static int dn_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
{
	struct sock *sk = sock->sk;
	int err;

	lock_sock(sk);
	err = __dn_getsockopt(sock, level, optname, optval, optlen, 0);
	release_sock(sk);

	return err;
}

static int __dn_getsockopt(struct socket *sock, int level,int optname, char __user *optval,int __user *optlen, int flags)
{
	struct	sock *sk = sock->sk;
	struct dn_scp *scp = DN_SK(sk);
	struct linkinfo_dn link;
	unsigned int r_len;
	void *r_data = NULL;
	unsigned int val;

	if(get_user(r_len , optlen))
		return -EFAULT;

	switch(optname) {
		case DSO_CONDATA:
			if (r_len > sizeof(struct optdata_dn))
				r_len = sizeof(struct optdata_dn);
			r_data = &scp->conndata_in;
			break;

		case DSO_DISDATA:
			if (r_len > sizeof(struct optdata_dn))
				r_len = sizeof(struct optdata_dn);
			r_data = &scp->discdata_in;
			break;

		case DSO_CONACCESS:
			if (r_len > sizeof(struct accessdata_dn))
				r_len = sizeof(struct accessdata_dn);
			r_data = &scp->accessdata;
			break;

		case DSO_ACCEPTMODE:
			if (r_len > sizeof(unsigned char))
				r_len = sizeof(unsigned char);
			r_data = &scp->accept_mode;
			break;

		case DSO_LINKINFO:
			if (r_len > sizeof(struct linkinfo_dn))
				r_len = sizeof(struct linkinfo_dn);

			switch(sock->state) {
				case SS_CONNECTING:
					link.idn_linkstate = LL_CONNECTING;
					break;
				case SS_DISCONNECTING:
					link.idn_linkstate = LL_DISCONNECTING;
					break;
				case SS_CONNECTED:
					link.idn_linkstate = LL_RUNNING;
					break;
				default:
					link.idn_linkstate = LL_INACTIVE;
			}

			link.idn_segsize = scp->segsize_rem;
			r_data = &link;
			break;

		default:
#ifdef CONFIG_NETFILTER
		{
			int val, len;

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

			val = nf_getsockopt(sk, PF_DECnet, optname,
							optval, &len);
			if (val >= 0)
				val = put_user(len, optlen);
			return val;
		}
#endif
		case DSO_STREAM:
		case DSO_SEQPACKET:
		case DSO_CONACCEPT:
		case DSO_CONREJECT:
			return -ENOPROTOOPT;

		case DSO_MAXWINDOW:
			if (r_len > sizeof(unsigned long))
				r_len = sizeof(unsigned long);
			r_data = &scp->max_window;
			break;

		case DSO_NODELAY:
			if (r_len > sizeof(int))
				r_len = sizeof(int);
			val = (scp->nonagle == 1);
			r_data = &val;
			break;

		case DSO_CORK:
			if (r_len > sizeof(int))
				r_len = sizeof(int);
			val = (scp->nonagle == 2);
			r_data = &val;
			break;

		case DSO_SERVICES:
			if (r_len > sizeof(unsigned char))
				r_len = sizeof(unsigned char);
			r_data = &scp->services_rem;
			break;

		case DSO_INFO:
			if (r_len > sizeof(unsigned char))
				r_len = sizeof(unsigned char);
			r_data = &scp->info_rem;
			break;
	}

	if (r_data) {
		if (copy_to_user(optval, r_data, r_len))
			return -EFAULT;
		if (put_user(r_len, optlen))
			return -EFAULT;
	}

	return 0;
}


static int dn_data_ready(struct sock *sk, struct sk_buff_head *q, int flags, int target)
{
	struct sk_buff *skb = q->next;
	int len = 0;

	if (flags & MSG_OOB)
		return !skb_queue_empty(q) ? 1 : 0;

	while(skb != (struct sk_buff *)q) {
		struct dn_skb_cb *cb = DN_SKB_CB(skb);
		len += skb->len;

		if (cb->nsp_flags & 0x40) {
			/* SOCK_SEQPACKET reads to EOM */
			if (sk->sk_type == SOCK_SEQPACKET)
				return 1;
			/* so does SOCK_STREAM unless WAITALL is specified */
			if (!(flags & MSG_WAITALL))
				return 1;
		}

		/* minimum data length for read exceeded */
		if (len >= target)
			return 1;

		skb = skb->next;
	}

	return 0;
}


static int dn_recvmsg(struct kiocb *iocb, struct socket *sock,
	struct msghdr *msg, size_t size, int flags)
{
	struct sock *sk = sock->sk;
	struct dn_scp *scp = DN_SK(sk);
	struct sk_buff_head *queue = &sk->sk_receive_queue;
	size_t target = size > 1 ? 1 : 0;
	size_t copied = 0;
	int rv = 0;
	struct sk_buff *skb, *nskb;
	struct dn_skb_cb *cb = NULL;
	unsigned char eor = 0;
	long timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);

	lock_sock(sk);

	if (sock_flag(sk, SOCK_ZAPPED)) {
		rv = -EADDRNOTAVAIL;
		goto out;
	}

	if (sk->sk_shutdown & RCV_SHUTDOWN) {
		rv = 0;
		goto out;
	}

	rv = dn_check_state(sk, NULL, 0, &timeo, flags);
	if (rv)
		goto out;

	if (flags & ~(MSG_CMSG_COMPAT|MSG_PEEK|MSG_OOB|MSG_WAITALL|MSG_DONTWAIT|MSG_NOSIGNAL)) {
		rv = -EOPNOTSUPP;
		goto out;
	}

	if (flags & MSG_OOB)
		queue = &scp->other_receive_queue;

	if (flags & MSG_WAITALL)
		target = size;


	/*
	 * See if there is data ready to read, sleep if there isn't
	 */
	for(;;) {
		if (sk->sk_err)
			goto out;

		if (!skb_queue_empty(&scp->other_receive_queue)) {
			if (!(flags & MSG_OOB)) {
				msg->msg_flags |= MSG_OOB;
				if (!scp->other_report) {
					scp->other_report = 1;
					goto out;
				}
			}
		}

		if (scp->state != DN_RUN)
			goto out;

		if (signal_pending(current)) {
			rv = sock_intr_errno(timeo);
			goto out;
		}

		if (dn_data_ready(sk, queue, flags, target))
			break;

		if (flags & MSG_DONTWAIT) {
			rv = -EWOULDBLOCK;
			goto out;
		}

		set_bit(SOCK_ASYNC_WAITDATA, &sock->flags);
		SOCK_SLEEP_PRE(sk)

		if (!dn_data_ready(sk, queue, flags, target))
			schedule();

		SOCK_SLEEP_POST(sk)
		clear_bit(SOCK_ASYNC_WAITDATA, &sock->flags);
	}

	for(skb = queue->next; skb != (struct sk_buff *)queue; skb = nskb) {
		unsigned int chunk = skb->len;
		cb = DN_SKB_CB(skb);

		if ((chunk + copied) > size)
			chunk = size - copied;

		if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
			rv = -EFAULT;
			break;
		}
		copied += chunk;

		if (!(flags & MSG_PEEK))
			skb_pull(skb, chunk);

		eor = cb->nsp_flags & 0x40;
		nskb = skb->next;

		if (skb->len == 0) {
			skb_unlink(skb, queue);
			kfree_skb(skb);
			/*
			 * N.B. Don't refer to skb or cb after this point
			 * in loop.
			 */
			if ((scp->flowloc_sw == DN_DONTSEND) && !dn_congested(sk)) {
				scp->flowloc_sw = DN_SEND;
				dn_nsp_send_link(sk, DN_SEND, 0);
			}
		}

		if (eor) {
			if (sk->sk_type == SOCK_SEQPACKET)
				break;
			if (!(flags & MSG_WAITALL))
				break;
		}

		if (flags & MSG_OOB)
			break;

		if (copied >= target)
			break;
	}

	rv = copied;


	if (eor && (sk->sk_type == SOCK_SEQPACKET))
		msg->msg_flags |= MSG_EOR;

out:
	if (rv == 0)
		rv = (flags & MSG_PEEK) ? -sk->sk_err : sock_error(sk);

	if ((rv >= 0) && msg->msg_name) {
		memcpy(msg->msg_name, &scp->peer, sizeof(struct sockaddr_dn));
		msg->msg_namelen = sizeof(struct sockaddr_dn);
	}

	release_sock(sk);

	return rv;
}


static inline int dn_queue_too_long(struct dn_scp *scp, struct sk_buff_head *queue, int flags)
{
	unsigned char fctype = scp->services_rem & NSP_FC_MASK;
	if (skb_queue_len(queue) >= scp->snd_window)
		return 1;
	if (fctype != NSP_FC_NONE) {