af_decnet.c

《嵌入式系统设计与实例开发实验教材二源码》Linux内核移植与编译实验

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

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

	return mask;
}

static int dn_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
	struct sock *sk = sock->sk;
	struct dn_scp *scp = DN_SK(sk);
	int err = -EOPNOTSUPP;
	unsigned long amount = 0;
	struct sk_buff *skb;
	int val;

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

	case SIOCATMARK:
		lock_sock(sk);
		val = (skb_queue_len(&scp->other_receive_queue) != 0);
		if (scp->state != DN_RUN)
			val = -ENOTCONN;
		release_sock(sk);
		return val;

#ifdef CONFIG_DECNET_ROUTER
	case SIOCADDRT:
	case SIOCDELRT:
		return dn_fib_ioctl(sock, cmd, arg);
#endif /* CONFIG_DECNET_ROUTER */

	case OSIOCSNETADDR:
		if (!capable(CAP_NET_ADMIN)) {
			err = -EPERM;
			break;
		}

		dn_dev_devices_off();

		decnet_address = (unsigned short)arg;
		dn_dn2eth(decnet_ether_address, dn_ntohs(decnet_address));

		dn_dev_devices_on();
		err = 0;
		break;

	case OSIOCGNETADDR:
		err = put_user(decnet_address, (unsigned short *)arg);
		break;
        case SIOCGIFCONF:
        case SIOCGIFFLAGS:
        case SIOCGIFBRDADDR:
                return dev_ioctl(cmd,(void *)arg);

	case TIOCOUTQ:
		amount = sk->sndbuf - atomic_read(&sk->wmem_alloc);
		if (amount < 0)
			amount = 0;
		err = put_user(amount, (int *)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->receive_queue.next;
			for(;;) {
				if (skb == (struct sk_buff *)&sk->receive_queue)
					break;
				amount += skb->len;
				skb = skb->next;
			}
		}
		release_sock(sk);
		err = put_user(amount, (int *)arg);
		break;
	}

	return err;
}

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

	lock_sock(sk);

	if (sk->zapped)
		goto out;

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

	sk->max_ack_backlog = backlog;
	sk->ack_backlog     = 0;
	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->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 *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 *optval, int optlen, int flags) 
{
	struct	sock *sk = sock->sk;
	struct dn_scp *scp = DN_SK(sk);
	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 (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 (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;

			scp->state = DN_CC;
			dn_send_conn_conf(sk, sk->allocation);
			err = dn_wait_accept(sock, sock->file->f_flags);
			return err;

		case DSO_CONREJECT:

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

			scp->state = DN_DR;
			sk->shutdown = SHUTDOWN_MASK;
			dn_nsp_send_disc(sk, 0x38, 0, 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 *optval, int *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 *optval,int *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;
}


/*
 * Used by send/recvmsg to wait until the socket is connected
 * before passing data.
 */
static int dn_wait_run(struct sock *sk, int flags)
{
	struct dn_scp *scp = DN_SK(sk);
	int err = 0;

	switch(scp->state) {
		case DN_RUN:
			return 0;

		case DN_CR:
			scp->state = DN_CC;
			dn_send_conn_conf(sk, sk->allocation);
			return dn_wait_accept(sk->socket, (flags & MSG_DONTWAIT) ? O_NONBLOCK : 0);
		case DN_CI:
		case DN_CC:
			break;
		default:
			return -ENOTCONN;
	}

	if (flags & MSG_DONTWAIT)
		return -EWOULDBLOCK;

	do {
		if ((err = sock_error(sk)) != 0)
			break;

		if (signal_pending(current)) {
			err = -ERESTARTSYS;
			break;
		}

		SOCK_SLEEP_PRE(sk)

		if (scp->state != DN_RUN)
			schedule();

		SOCK_SLEEP_POST(sk)

	} while(scp->state != DN_RUN);

	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_len(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->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 socket *sock, struct msghdr *msg, int size,
	int flags, struct scm_cookie *scm)
{
	struct sock *sk = sock->sk;
	struct dn_scp *scp = DN_SK(sk);
	struct sk_buff_head *queue = &sk->receive_queue;
	int target = size > 1 ? 1 : 0;
	int copied = 0;
	int rv = 0;
	struct sk_buff *skb, *nskb;
	struct dn_skb_cb *cb = NULL;
	unsigned char eor = 0;

	lock_sock(sk);

	if (sk->zapped) {
		rv = -EADDRNOTAVAIL;
		goto out;
	}

	if ((rv = dn_wait_run(sk, flags)) != 0)
		goto out;

	if (sk->shutdown & RCV_SHUTDOWN) {
		send_sig(SIGPIPE, current, 0);
		rv = -EPIPE;
		goto out;
	}

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

	if (flags & MSG_OOB)