Fixed MTP to work with TWRP

net/netrom/Makefile

@@ -0,0 +1,9 @@
+#
+# Makefile for the Linux NET/ROM layer.
+#
+
+obj-$(CONFIG_NETROM) += netrom.o
+
+netrom-y		:= af_netrom.o nr_dev.o nr_in.o nr_loopback.o \
+			   nr_out.o nr_route.o nr_subr.o nr_timer.o
+netrom-$(CONFIG_SYSCTL)	+= sysctl_net_netrom.o

net/netrom/nr_dev.c

@@ -0,0 +1,212 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ */
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/sysctl.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/errno.h>
+#include <linux/fcntl.h>
+#include <linux/in.h>
+#include <linux/if_ether.h>	/* For the statistics structure. */
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include <asm/io.h>
+
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+
+#include <net/ip.h>
+#include <net/arp.h>
+
+#include <net/ax25.h>
+#include <net/netrom.h>
+
+/*
+ *	Only allow IP over NET/ROM frames through if the netrom device is up.
+ */
+
+int nr_rx_ip(struct sk_buff *skb, struct net_device *dev)
+{
+	struct net_device_stats *stats = &dev->stats;
+
+	if (!netif_running(dev)) {
+		stats->rx_dropped++;
+		return 0;
+	}
+
+	stats->rx_packets++;
+	stats->rx_bytes += skb->len;
+
+	skb->protocol = htons(ETH_P_IP);
+
+	/* Spoof incoming device */
+	skb->dev      = dev;
+	skb->mac_header = skb->network_header;
+	skb_reset_network_header(skb);
+	skb->pkt_type = PACKET_HOST;
+
+	netif_rx(skb);
+
+	return 1;
+}
+
+#ifdef CONFIG_INET
+
+static int nr_rebuild_header(struct sk_buff *skb)
+{
+	unsigned char *bp = skb->data;
+
+	if (arp_find(bp + 7, skb))
+		return 1;
+
+	bp[6] &= ~AX25_CBIT;
+	bp[6] &= ~AX25_EBIT;
+	bp[6] |= AX25_SSSID_SPARE;
+	bp    += AX25_ADDR_LEN;
+
+	bp[6] &= ~AX25_CBIT;
+	bp[6] |= AX25_EBIT;
+	bp[6] |= AX25_SSSID_SPARE;
+
+	return 0;
+}
+
+#else
+
+static int nr_rebuild_header(struct sk_buff *skb)
+{
+	return 1;
+}
+
+#endif
+
+static int nr_header(struct sk_buff *skb, struct net_device *dev,
+		     unsigned short type,
+		     const void *daddr, const void *saddr, unsigned int len)
+{
+	unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
+
+	memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len);
+	buff[6] &= ~AX25_CBIT;
+	buff[6] &= ~AX25_EBIT;
+	buff[6] |= AX25_SSSID_SPARE;
+	buff    += AX25_ADDR_LEN;
+
+	if (daddr != NULL)
+		memcpy(buff, daddr, dev->addr_len);
+	buff[6] &= ~AX25_CBIT;
+	buff[6] |= AX25_EBIT;
+	buff[6] |= AX25_SSSID_SPARE;
+	buff    += AX25_ADDR_LEN;
+
+	*buff++ = sysctl_netrom_network_ttl_initialiser;
+
+	*buff++ = NR_PROTO_IP;
+	*buff++ = NR_PROTO_IP;
+	*buff++ = 0;
+	*buff++ = 0;
+	*buff++ = NR_PROTOEXT;
+
+	if (daddr != NULL)
+		return 37;
+
+	return -37;
+}
+
+static int __must_check nr_set_mac_address(struct net_device *dev, void *addr)
+{
+	struct sockaddr *sa = addr;
+	int err;
+
+	if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len))
+		return 0;
+
+	if (dev->flags & IFF_UP) {
+		err = ax25_listen_register((ax25_address *)sa->sa_data, NULL);
+		if (err)
+			return err;
+
+		ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
+	}
+
+	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
+
+	return 0;
+}
+
+static int nr_open(struct net_device *dev)
+{
+	int err;
+
+	err = ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
+	if (err)
+		return err;
+
+	netif_start_queue(dev);
+
+	return 0;
+}
+
+static int nr_close(struct net_device *dev)
+{
+	ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
+	netif_stop_queue(dev);
+	return 0;
+}
+
+static netdev_tx_t nr_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct net_device_stats *stats = &dev->stats;
+	unsigned int len = skb->len;
+
+	if (!nr_route_frame(skb, NULL)) {
+		kfree_skb(skb);
+		stats->tx_errors++;
+		return NETDEV_TX_OK;
+	}
+
+	stats->tx_packets++;
+	stats->tx_bytes += len;
+
+	return NETDEV_TX_OK;
+}
+
+static const struct header_ops nr_header_ops = {
+	.create	= nr_header,
+	.rebuild= nr_rebuild_header,
+};
+
+static const struct net_device_ops nr_netdev_ops = {
+	.ndo_open		= nr_open,
+	.ndo_stop		= nr_close,
+	.ndo_start_xmit		= nr_xmit,
+	.ndo_set_mac_address    = nr_set_mac_address,
+};
+
+void nr_setup(struct net_device *dev)
+{
+	dev->mtu		= NR_MAX_PACKET_SIZE;
+	dev->netdev_ops		= &nr_netdev_ops;
+	dev->header_ops		= &nr_header_ops;
+	dev->hard_header_len	= NR_NETWORK_LEN + NR_TRANSPORT_LEN;
+	dev->addr_len		= AX25_ADDR_LEN;
+	dev->type		= ARPHRD_NETROM;
+
+	/* New-style flags. */
+	dev->flags		= IFF_NOARP;
+}

net/netrom/nr_in.c

@@ -0,0 +1,305 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk)
+ */
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
+#include <linux/uaccess.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/netrom.h>
+
+static int nr_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more)
+{
+	struct sk_buff *skbo, *skbn = skb;
+	struct nr_sock *nr = nr_sk(sk);
+
+	skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
+
+	nr_start_idletimer(sk);
+
+	if (more) {
+		nr->fraglen += skb->len;
+		skb_queue_tail(&nr->frag_queue, skb);
+		return 0;
+	}
+
+	if (!more && nr->fraglen > 0) {	/* End of fragment */
+		nr->fraglen += skb->len;
+		skb_queue_tail(&nr->frag_queue, skb);
+
+		if ((skbn = alloc_skb(nr->fraglen, GFP_ATOMIC)) == NULL)
+			return 1;
+
+		skb_reset_transport_header(skbn);
+
+		while ((skbo = skb_dequeue(&nr->frag_queue)) != NULL) {
+			skb_copy_from_linear_data(skbo,
+						  skb_put(skbn, skbo->len),
+						  skbo->len);
+			kfree_skb(skbo);
+		}
+
+		nr->fraglen = 0;
+	}
+
+	return sock_queue_rcv_skb(sk, skbn);
+}
+
+/*
+ * State machine for state 1, Awaiting Connection State.
+ * The handling of the timer(s) is in file nr_timer.c.
+ * Handling of state 0 and connection release is in netrom.c.
+ */
+static int nr_state1_machine(struct sock *sk, struct sk_buff *skb,
+	int frametype)
+{
+	switch (frametype) {
+	case NR_CONNACK: {
+		struct nr_sock *nr = nr_sk(sk);
+
+		nr_stop_t1timer(sk);
+		nr_start_idletimer(sk);
+		nr->your_index = skb->data[17];
+		nr->your_id    = skb->data[18];
+		nr->vs	       = 0;
+		nr->va	       = 0;
+		nr->vr	       = 0;
+		nr->vl	       = 0;
+		nr->state      = NR_STATE_3;
+		nr->n2count    = 0;
+		nr->window     = skb->data[20];
+		sk->sk_state   = TCP_ESTABLISHED;
+		if (!sock_flag(sk, SOCK_DEAD))
+			sk->sk_state_change(sk);
+		break;
+	}
+
+	case NR_CONNACK | NR_CHOKE_FLAG:
+		nr_disconnect(sk, ECONNREFUSED);
+		break;
+
+	case NR_RESET:
+		if (sysctl_netrom_reset_circuit)
+			nr_disconnect(sk, ECONNRESET);
+		break;
+
+	default:
+		break;
+	}
+	return 0;
+}
+
+/*
+ * State machine for state 2, Awaiting Release State.
+ * The handling of the timer(s) is in file nr_timer.c
+ * Handling of state 0 and connection release is in netrom.c.
+ */
+static int nr_state2_machine(struct sock *sk, struct sk_buff *skb,
+	int frametype)
+{
+	switch (frametype) {
+	case NR_CONNACK | NR_CHOKE_FLAG:
+		nr_disconnect(sk, ECONNRESET);
+		break;
+
+	case NR_DISCREQ:
+		nr_write_internal(sk, NR_DISCACK);
+
+	case NR_DISCACK:
+		nr_disconnect(sk, 0);
+		break;
+
+	case NR_RESET:
+		if (sysctl_netrom_reset_circuit)
+			nr_disconnect(sk, ECONNRESET);
+		break;
+
+	default:
+		break;
+	}
+	return 0;
+}
+
+/*
+ * State machine for state 3, Connected State.
+ * The handling of the timer(s) is in file nr_timer.c
+ * Handling of state 0 and connection release is in netrom.c.
+ */
+static int nr_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype)
+{
+	struct nr_sock *nrom = nr_sk(sk);
+	struct sk_buff_head temp_queue;
+	struct sk_buff *skbn;
+	unsigned short save_vr;
+	unsigned short nr, ns;
+	int queued = 0;
+
+	nr = skb->data[18];
+	ns = skb->data[17];
+
+	switch (frametype) {
+	case NR_CONNREQ:
+		nr_write_internal(sk, NR_CONNACK);
+		break;
+
+	case NR_DISCREQ:
+		nr_write_internal(sk, NR_DISCACK);
+		nr_disconnect(sk, 0);
+		break;
+
+	case NR_CONNACK | NR_CHOKE_FLAG:
+	case NR_DISCACK:
+		nr_disconnect(sk, ECONNRESET);
+		break;
+
+	case NR_INFOACK:
+	case NR_INFOACK | NR_CHOKE_FLAG:
+	case NR_INFOACK | NR_NAK_FLAG:
+	case NR_INFOACK | NR_NAK_FLAG | NR_CHOKE_FLAG:
+		if (frametype & NR_CHOKE_FLAG) {
+			nrom->condition |= NR_COND_PEER_RX_BUSY;
+			nr_start_t4timer(sk);
+		} else {
+			nrom->condition &= ~NR_COND_PEER_RX_BUSY;
+			nr_stop_t4timer(sk);
+		}
+		if (!nr_validate_nr(sk, nr)) {
+			break;
+		}
+		if (frametype & NR_NAK_FLAG) {
+			nr_frames_acked(sk, nr);
+			nr_send_nak_frame(sk);
+		} else {
+			if (nrom->condition & NR_COND_PEER_RX_BUSY) {
+				nr_frames_acked(sk, nr);
+			} else {
+				nr_check_iframes_acked(sk, nr);
+			}
+		}
+		break;
+
+	case NR_INFO:
+	case NR_INFO | NR_NAK_FLAG:
+	case NR_INFO | NR_CHOKE_FLAG:
+	case NR_INFO | NR_MORE_FLAG:
+	case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG:
+	case NR_INFO | NR_CHOKE_FLAG | NR_MORE_FLAG:
+	case NR_INFO | NR_NAK_FLAG | NR_MORE_FLAG:
+	case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG | NR_MORE_FLAG:
+		if (frametype & NR_CHOKE_FLAG) {
+			nrom->condition |= NR_COND_PEER_RX_BUSY;
+			nr_start_t4timer(sk);
+		} else {
+			nrom->condition &= ~NR_COND_PEER_RX_BUSY;
+			nr_stop_t4timer(sk);
+		}
+		if (nr_validate_nr(sk, nr)) {
+			if (frametype & NR_NAK_FLAG) {
+				nr_frames_acked(sk, nr);
+				nr_send_nak_frame(sk);
+			} else {
+				if (nrom->condition & NR_COND_PEER_RX_BUSY) {
+					nr_frames_acked(sk, nr);
+				} else {
+					nr_check_iframes_acked(sk, nr);
+				}
+			}
+		}
+		queued = 1;
+		skb_queue_head(&nrom->reseq_queue, skb);
+		if (nrom->condition & NR_COND_OWN_RX_BUSY)
+			break;
+		skb_queue_head_init(&temp_queue);
+		do {
+			save_vr = nrom->vr;
+			while ((skbn = skb_dequeue(&nrom->reseq_queue)) != NULL) {
+				ns = skbn->data[17];
+				if (ns == nrom->vr) {
+					if (nr_queue_rx_frame(sk, skbn, frametype & NR_MORE_FLAG) == 0) {
+						nrom->vr = (nrom->vr + 1) % NR_MODULUS;
+					} else {
+						nrom->condition |= NR_COND_OWN_RX_BUSY;
+						skb_queue_tail(&temp_queue, skbn);
+					}
+				} else if (nr_in_rx_window(sk, ns)) {
+					skb_queue_tail(&temp_queue, skbn);
+				} else {
+					kfree_skb(skbn);
+				}
+			}
+			while ((skbn = skb_dequeue(&temp_queue)) != NULL) {
+				skb_queue_tail(&nrom->reseq_queue, skbn);
+			}
+		} while (save_vr != nrom->vr);
+		/*
+		 * Window is full, ack it immediately.
+		 */
+		if (((nrom->vl + nrom->window) % NR_MODULUS) == nrom->vr) {
+			nr_enquiry_response(sk);
+		} else {
+			if (!(nrom->condition & NR_COND_ACK_PENDING)) {
+				nrom->condition |= NR_COND_ACK_PENDING;
+				nr_start_t2timer(sk);
+			}
+		}
+		break;
+
+	case NR_RESET:
+		if (sysctl_netrom_reset_circuit)
+			nr_disconnect(sk, ECONNRESET);
+		break;
+
+	default:
+		break;
+	}
+	return queued;
+}
+
+/* Higher level upcall for a LAPB frame - called with sk locked */
+int nr_process_rx_frame(struct sock *sk, struct sk_buff *skb)
+{
+	struct nr_sock *nr = nr_sk(sk);
+	int queued = 0, frametype;
+
+	if (nr->state == NR_STATE_0)
+		return 0;
+
+	frametype = skb->data[19];
+
+	switch (nr->state) {
+	case NR_STATE_1:
+		queued = nr_state1_machine(sk, skb, frametype);
+		break;
+	case NR_STATE_2:
+		queued = nr_state2_machine(sk, skb, frametype);
+		break;
+	case NR_STATE_3:
+		queued = nr_state3_machine(sk, skb, frametype);
+		break;
+	}
+
+	nr_kick(sk);
+
+	return queued;
+}

net/netrom/nr_loopback.c

@@ -0,0 +1,77 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
+ */
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/socket.h>
+#include <linux/timer.h>
+#include <net/ax25.h>
+#include <linux/skbuff.h>
+#include <net/netrom.h>
+#include <linux/init.h>
+
+static void nr_loopback_timer(unsigned long);
+
+static struct sk_buff_head loopback_queue;
+static DEFINE_TIMER(loopback_timer, nr_loopback_timer, 0, 0);
+
+void __init nr_loopback_init(void)
+{
+	skb_queue_head_init(&loopback_queue);
+}
+
+static inline int nr_loopback_running(void)
+{
+	return timer_pending(&loopback_timer);
+}
+
+int nr_loopback_queue(struct sk_buff *skb)
+{
+	struct sk_buff *skbn;
+
+	if ((skbn = alloc_skb(skb->len, GFP_ATOMIC)) != NULL) {
+		skb_copy_from_linear_data(skb, skb_put(skbn, skb->len), skb->len);
+		skb_reset_transport_header(skbn);
+
+		skb_queue_tail(&loopback_queue, skbn);
+
+		if (!nr_loopback_running())
+			mod_timer(&loopback_timer, jiffies + 10);
+	}
+
+	kfree_skb(skb);
+	return 1;
+}
+
+static void nr_loopback_timer(unsigned long param)
+{
+	struct sk_buff *skb;
+	ax25_address *nr_dest;
+	struct net_device *dev;
+
+	if ((skb = skb_dequeue(&loopback_queue)) != NULL) {
+		nr_dest = (ax25_address *)(skb->data + 7);
+
+		dev = nr_dev_get(nr_dest);
+
+		if (dev == NULL || nr_rx_frame(skb, dev) == 0)
+			kfree_skb(skb);
+
+		if (dev != NULL)
+			dev_put(dev);
+
+		if (!skb_queue_empty(&loopback_queue) && !nr_loopback_running())
+			mod_timer(&loopback_timer, jiffies + 10);
+	}
+}
+
+void __exit nr_loopback_clear(void)
+{
+	del_timer_sync(&loopback_timer);
+	skb_queue_purge(&loopback_queue);
+}

net/netrom/nr_out.c

@@ -0,0 +1,273 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk)
+ */
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <linux/uaccess.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/netrom.h>
+
+/*
+ *	This is where all NET/ROM frames pass, except for IP-over-NET/ROM which
+ *	cannot be fragmented in this manner.
+ */
+void nr_output(struct sock *sk, struct sk_buff *skb)
+{
+	struct sk_buff *skbn;
+	unsigned char transport[NR_TRANSPORT_LEN];
+	int err, frontlen, len;
+
+	if (skb->len - NR_TRANSPORT_LEN > NR_MAX_PACKET_SIZE) {
+		/* Save a copy of the Transport Header */
+		skb_copy_from_linear_data(skb, transport, NR_TRANSPORT_LEN);
+		skb_pull(skb, NR_TRANSPORT_LEN);
+
+		frontlen = skb_headroom(skb);
+
+		while (skb->len > 0) {
+			if ((skbn = sock_alloc_send_skb(sk, frontlen + NR_MAX_PACKET_SIZE, 0, &err)) == NULL)
+				return;
+
+			skb_reserve(skbn, frontlen);
+
+			len = (NR_MAX_PACKET_SIZE > skb->len) ? skb->len : NR_MAX_PACKET_SIZE;
+
+			/* Copy the user data */
+			skb_copy_from_linear_data(skb, skb_put(skbn, len), len);
+			skb_pull(skb, len);
+
+			/* Duplicate the Transport Header */
+			skb_push(skbn, NR_TRANSPORT_LEN);
+			skb_copy_to_linear_data(skbn, transport,
+						NR_TRANSPORT_LEN);
+			if (skb->len > 0)
+				skbn->data[4] |= NR_MORE_FLAG;
+
+			skb_queue_tail(&sk->sk_write_queue, skbn); /* Throw it on the queue */
+		}
+
+		kfree_skb(skb);
+	} else {
+		skb_queue_tail(&sk->sk_write_queue, skb);		/* Throw it on the queue */
+	}
+
+	nr_kick(sk);
+}
+
+/*
+ *	This procedure is passed a buffer descriptor for an iframe. It builds
+ *	the rest of the control part of the frame and then writes it out.
+ */
+static void nr_send_iframe(struct sock *sk, struct sk_buff *skb)
+{
+	struct nr_sock *nr = nr_sk(sk);
+
+	if (skb == NULL)
+		return;
+
+	skb->data[2] = nr->vs;
+	skb->data[3] = nr->vr;
+
+	if (nr->condition & NR_COND_OWN_RX_BUSY)
+		skb->data[4] |= NR_CHOKE_FLAG;
+
+	nr_start_idletimer(sk);
+
+	nr_transmit_buffer(sk, skb);
+}
+
+void nr_send_nak_frame(struct sock *sk)
+{
+	struct sk_buff *skb, *skbn;
+	struct nr_sock *nr = nr_sk(sk);
+
+	if ((skb = skb_peek(&nr->ack_queue)) == NULL)
+		return;
+
+	if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL)
+		return;
+
+	skbn->data[2] = nr->va;
+	skbn->data[3] = nr->vr;
+
+	if (nr->condition & NR_COND_OWN_RX_BUSY)
+		skbn->data[4] |= NR_CHOKE_FLAG;
+
+	nr_transmit_buffer(sk, skbn);
+
+	nr->condition &= ~NR_COND_ACK_PENDING;
+	nr->vl         = nr->vr;
+
+	nr_stop_t1timer(sk);
+}
+
+void nr_kick(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+	struct sk_buff *skb, *skbn;
+	unsigned short start, end;
+
+	if (nr->state != NR_STATE_3)
+		return;
+
+	if (nr->condition & NR_COND_PEER_RX_BUSY)
+		return;
+
+	if (!skb_peek(&sk->sk_write_queue))
+		return;
+
+	start = (skb_peek(&nr->ack_queue) == NULL) ? nr->va : nr->vs;
+	end   = (nr->va + nr->window) % NR_MODULUS;
+
+	if (start == end)
+		return;
+
+	nr->vs = start;
+
+	/*
+	 * Transmit data until either we're out of data to send or
+	 * the window is full.
+	 */
+
+	/*
+	 * Dequeue the frame and copy it.
+	 */
+	skb = skb_dequeue(&sk->sk_write_queue);
+
+	do {
+		if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
+			skb_queue_head(&sk->sk_write_queue, skb);
+			break;
+		}
+
+		skb_set_owner_w(skbn, sk);
+
+		/*
+		 * Transmit the frame copy.
+		 */
+		nr_send_iframe(sk, skbn);
+
+		nr->vs = (nr->vs + 1) % NR_MODULUS;
+
+		/*
+		 * Requeue the original data frame.
+		 */
+		skb_queue_tail(&nr->ack_queue, skb);
+
+	} while (nr->vs != end &&
+		 (skb = skb_dequeue(&sk->sk_write_queue)) != NULL);
+
+	nr->vl         = nr->vr;
+	nr->condition &= ~NR_COND_ACK_PENDING;
+
+	if (!nr_t1timer_running(sk))
+		nr_start_t1timer(sk);
+}
+
+void nr_transmit_buffer(struct sock *sk, struct sk_buff *skb)
+{
+	struct nr_sock *nr = nr_sk(sk);
+	unsigned char *dptr;
+
+	/*
+	 *	Add the protocol byte and network header.
+	 */
+	dptr = skb_push(skb, NR_NETWORK_LEN);
+
+	memcpy(dptr, &nr->source_addr, AX25_ADDR_LEN);
+	dptr[6] &= ~AX25_CBIT;
+	dptr[6] &= ~AX25_EBIT;
+	dptr[6] |= AX25_SSSID_SPARE;
+	dptr += AX25_ADDR_LEN;
+
+	memcpy(dptr, &nr->dest_addr, AX25_ADDR_LEN);
+	dptr[6] &= ~AX25_CBIT;
+	dptr[6] |= AX25_EBIT;
+	dptr[6] |= AX25_SSSID_SPARE;
+	dptr += AX25_ADDR_LEN;
+
+	*dptr++ = sysctl_netrom_network_ttl_initialiser;
+
+	if (!nr_route_frame(skb, NULL)) {
+		kfree_skb(skb);
+		nr_disconnect(sk, ENETUNREACH);
+	}
+}
+
+/*
+ * The following routines are taken from page 170 of the 7th ARRL Computer
+ * Networking Conference paper, as is the whole state machine.
+ */
+
+void nr_establish_data_link(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+
+	nr->condition = 0x00;
+	nr->n2count   = 0;
+
+	nr_write_internal(sk, NR_CONNREQ);
+
+	nr_stop_t2timer(sk);
+	nr_stop_t4timer(sk);
+	nr_stop_idletimer(sk);
+	nr_start_t1timer(sk);
+}
+
+/*
+ * Never send a NAK when we are CHOKEd.
+ */
+void nr_enquiry_response(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+	int frametype = NR_INFOACK;
+
+	if (nr->condition & NR_COND_OWN_RX_BUSY) {
+		frametype |= NR_CHOKE_FLAG;
+	} else {
+		if (skb_peek(&nr->reseq_queue) != NULL)
+			frametype |= NR_NAK_FLAG;
+	}
+
+	nr_write_internal(sk, frametype);
+
+	nr->vl         = nr->vr;
+	nr->condition &= ~NR_COND_ACK_PENDING;
+}
+
+void nr_check_iframes_acked(struct sock *sk, unsigned short nr)
+{
+	struct nr_sock *nrom = nr_sk(sk);
+
+	if (nrom->vs == nr) {
+		nr_frames_acked(sk, nr);
+		nr_stop_t1timer(sk);
+		nrom->n2count = 0;
+	} else {
+		if (nrom->va != nr) {
+			nr_frames_acked(sk, nr);
+			nr_start_t1timer(sk);
+		}
+	}
+}

net/netrom/nr_subr.c

@@ -0,0 +1,281 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ */
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
+#include <linux/uaccess.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/netrom.h>
+
+/*
+ *	This routine purges all of the queues of frames.
+ */
+void nr_clear_queues(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+
+	skb_queue_purge(&sk->sk_write_queue);
+	skb_queue_purge(&nr->ack_queue);
+	skb_queue_purge(&nr->reseq_queue);
+	skb_queue_purge(&nr->frag_queue);
+}
+
+/*
+ * This routine purges the input queue of those frames that have been
+ * acknowledged. This replaces the boxes labelled "V(a) <- N(r)" on the
+ * SDL diagram.
+ */
+void nr_frames_acked(struct sock *sk, unsigned short nr)
+{
+	struct nr_sock *nrom = nr_sk(sk);
+	struct sk_buff *skb;
+
+	/*
+	 * Remove all the ack-ed frames from the ack queue.
+	 */
+	if (nrom->va != nr) {
+		while (skb_peek(&nrom->ack_queue) != NULL && nrom->va != nr) {
+			skb = skb_dequeue(&nrom->ack_queue);
+			kfree_skb(skb);
+			nrom->va = (nrom->va + 1) % NR_MODULUS;
+		}
+	}
+}
+
+/*
+ * Requeue all the un-ack-ed frames on the output queue to be picked
+ * up by nr_kick called from the timer. This arrangement handles the
+ * possibility of an empty output queue.
+ */
+void nr_requeue_frames(struct sock *sk)
+{
+	struct sk_buff *skb, *skb_prev = NULL;
+
+	while ((skb = skb_dequeue(&nr_sk(sk)->ack_queue)) != NULL) {
+		if (skb_prev == NULL)
+			skb_queue_head(&sk->sk_write_queue, skb);
+		else
+			skb_append(skb_prev, skb, &sk->sk_write_queue);
+		skb_prev = skb;
+	}
+}
+
+/*
+ *	Validate that the value of nr is between va and vs. Return true or
+ *	false for testing.
+ */
+int nr_validate_nr(struct sock *sk, unsigned short nr)
+{
+	struct nr_sock *nrom = nr_sk(sk);
+	unsigned short vc = nrom->va;
+
+	while (vc != nrom->vs) {
+		if (nr == vc) return 1;
+		vc = (vc + 1) % NR_MODULUS;
+	}
+
+	return nr == nrom->vs;
+}
+
+/*
+ *	Check that ns is within the receive window.
+ */
+int nr_in_rx_window(struct sock *sk, unsigned short ns)
+{
+	struct nr_sock *nr = nr_sk(sk);
+	unsigned short vc = nr->vr;
+	unsigned short vt = (nr->vl + nr->window) % NR_MODULUS;
+
+	while (vc != vt) {
+		if (ns == vc) return 1;
+		vc = (vc + 1) % NR_MODULUS;
+	}
+
+	return 0;
+}
+
+/*
+ *  This routine is called when the HDLC layer internally generates a
+ *  control frame.
+ */
+void nr_write_internal(struct sock *sk, int frametype)
+{
+	struct nr_sock *nr = nr_sk(sk);
+	struct sk_buff *skb;
+	unsigned char  *dptr;
+	int len, timeout;
+
+	len = NR_NETWORK_LEN + NR_TRANSPORT_LEN;
+
+	switch (frametype & 0x0F) {
+	case NR_CONNREQ:
+		len += 17;
+		break;
+	case NR_CONNACK:
+		len += (nr->bpqext) ? 2 : 1;
+		break;
+	case NR_DISCREQ:
+	case NR_DISCACK:
+	case NR_INFOACK:
+		break;
+	default:
+		printk(KERN_ERR "NET/ROM: nr_write_internal - invalid frame type %d\n", frametype);
+		return;
+	}
+
+	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
+		return;
+
+	/*
+	 *	Space for AX.25 and NET/ROM network header
+	 */
+	skb_reserve(skb, NR_NETWORK_LEN);
+
+	dptr = skb_put(skb, skb_tailroom(skb));
+
+	switch (frametype & 0x0F) {
+	case NR_CONNREQ:
+		timeout  = nr->t1 / HZ;
+		*dptr++  = nr->my_index;
+		*dptr++  = nr->my_id;
+		*dptr++  = 0;
+		*dptr++  = 0;
+		*dptr++  = frametype;
+		*dptr++  = nr->window;
+		memcpy(dptr, &nr->user_addr, AX25_ADDR_LEN);
+		dptr[6] &= ~AX25_CBIT;
+		dptr[6] &= ~AX25_EBIT;
+		dptr[6] |= AX25_SSSID_SPARE;
+		dptr    += AX25_ADDR_LEN;
+		memcpy(dptr, &nr->source_addr, AX25_ADDR_LEN);
+		dptr[6] &= ~AX25_CBIT;
+		dptr[6] &= ~AX25_EBIT;
+		dptr[6] |= AX25_SSSID_SPARE;
+		dptr    += AX25_ADDR_LEN;
+		*dptr++  = timeout % 256;
+		*dptr++  = timeout / 256;
+		break;
+
+	case NR_CONNACK:
+		*dptr++ = nr->your_index;
+		*dptr++ = nr->your_id;
+		*dptr++ = nr->my_index;
+		*dptr++ = nr->my_id;
+		*dptr++ = frametype;
+		*dptr++ = nr->window;
+		if (nr->bpqext) *dptr++ = sysctl_netrom_network_ttl_initialiser;
+		break;
+
+	case NR_DISCREQ:
+	case NR_DISCACK:
+		*dptr++ = nr->your_index;
+		*dptr++ = nr->your_id;
+		*dptr++ = 0;
+		*dptr++ = 0;
+		*dptr++ = frametype;
+		break;
+
+	case NR_INFOACK:
+		*dptr++ = nr->your_index;
+		*dptr++ = nr->your_id;
+		*dptr++ = 0;
+		*dptr++ = nr->vr;
+		*dptr++ = frametype;
+		break;
+	}
+
+	nr_transmit_buffer(sk, skb);
+}
+
+/*
+ * This routine is called to send an error reply.
+ */
+void __nr_transmit_reply(struct sk_buff *skb, int mine, unsigned char cmdflags)
+{
+	struct sk_buff *skbn;
+	unsigned char *dptr;
+	int len;
+
+	len = NR_NETWORK_LEN + NR_TRANSPORT_LEN + 1;
+
+	if ((skbn = alloc_skb(len, GFP_ATOMIC)) == NULL)
+		return;
+
+	skb_reserve(skbn, 0);
+
+	dptr = skb_put(skbn, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
+
+	skb_copy_from_linear_data_offset(skb, 7, dptr, AX25_ADDR_LEN);
+	dptr[6] &= ~AX25_CBIT;
+	dptr[6] &= ~AX25_EBIT;
+	dptr[6] |= AX25_SSSID_SPARE;
+	dptr += AX25_ADDR_LEN;
+
+	skb_copy_from_linear_data(skb, dptr, AX25_ADDR_LEN);
+	dptr[6] &= ~AX25_CBIT;
+	dptr[6] |= AX25_EBIT;
+	dptr[6] |= AX25_SSSID_SPARE;
+	dptr += AX25_ADDR_LEN;
+
+	*dptr++ = sysctl_netrom_network_ttl_initialiser;
+
+	if (mine) {
+		*dptr++ = 0;
+		*dptr++ = 0;
+		*dptr++ = skb->data[15];
+		*dptr++ = skb->data[16];
+	} else {
+		*dptr++ = skb->data[15];
+		*dptr++ = skb->data[16];
+		*dptr++ = 0;
+		*dptr++ = 0;
+	}
+
+	*dptr++ = cmdflags;
+	*dptr++ = 0;
+
+	if (!nr_route_frame(skbn, NULL))
+		kfree_skb(skbn);
+}
+
+void nr_disconnect(struct sock *sk, int reason)
+{
+	nr_stop_t1timer(sk);
+	nr_stop_t2timer(sk);
+	nr_stop_t4timer(sk);
+	nr_stop_idletimer(sk);
+
+	nr_clear_queues(sk);
+
+	nr_sk(sk)->state = NR_STATE_0;
+
+	sk->sk_state     = TCP_CLOSE;
+	sk->sk_err       = reason;
+	sk->sk_shutdown |= SEND_SHUTDOWN;
+
+	if (!sock_flag(sk, SOCK_DEAD)) {
+		sk->sk_state_change(sk);
+		sock_set_flag(sk, SOCK_DEAD);
+	}
+}

net/netrom/nr_timer.c

@@ -0,0 +1,248 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ * Copyright (C) 2002 Ralf Baechle DO1GRB (ralf@gnu.org)
+ */
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/jiffies.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
+#include <linux/uaccess.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/netrom.h>
+
+static void nr_heartbeat_expiry(unsigned long);
+static void nr_t1timer_expiry(unsigned long);
+static void nr_t2timer_expiry(unsigned long);
+static void nr_t4timer_expiry(unsigned long);
+static void nr_idletimer_expiry(unsigned long);
+
+void nr_init_timers(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+
+	setup_timer(&nr->t1timer, nr_t1timer_expiry, (unsigned long)sk);
+	setup_timer(&nr->t2timer, nr_t2timer_expiry, (unsigned long)sk);
+	setup_timer(&nr->t4timer, nr_t4timer_expiry, (unsigned long)sk);
+	setup_timer(&nr->idletimer, nr_idletimer_expiry, (unsigned long)sk);
+
+	/* initialized by sock_init_data */
+	sk->sk_timer.data     = (unsigned long)sk;
+	sk->sk_timer.function = &nr_heartbeat_expiry;
+}
+
+void nr_start_t1timer(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+
+	mod_timer(&nr->t1timer, jiffies + nr->t1);
+}
+
+void nr_start_t2timer(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+
+	mod_timer(&nr->t2timer, jiffies + nr->t2);
+}
+
+void nr_start_t4timer(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+
+	mod_timer(&nr->t4timer, jiffies + nr->t4);
+}
+
+void nr_start_idletimer(struct sock *sk)
+{
+	struct nr_sock *nr = nr_sk(sk);
+
+	if (nr->idle > 0)
+		mod_timer(&nr->idletimer, jiffies + nr->idle);
+}
+
+void nr_start_heartbeat(struct sock *sk)
+{
+	mod_timer(&sk->sk_timer, jiffies + 5 * HZ);
+}
+
+void nr_stop_t1timer(struct sock *sk)
+{
+	del_timer(&nr_sk(sk)->t1timer);
+}
+
+void nr_stop_t2timer(struct sock *sk)
+{
+	del_timer(&nr_sk(sk)->t2timer);
+}
+
+void nr_stop_t4timer(struct sock *sk)
+{
+	del_timer(&nr_sk(sk)->t4timer);
+}
+
+void nr_stop_idletimer(struct sock *sk)
+{
+	del_timer(&nr_sk(sk)->idletimer);
+}
+
+void nr_stop_heartbeat(struct sock *sk)
+{
+	del_timer(&sk->sk_timer);
+}
+
+int nr_t1timer_running(struct sock *sk)
+{
+	return timer_pending(&nr_sk(sk)->t1timer);
+}
+
+static void nr_heartbeat_expiry(unsigned long param)
+{
+	struct sock *sk = (struct sock *)param;
+	struct nr_sock *nr = nr_sk(sk);
+
+	bh_lock_sock(sk);
+	switch (nr->state) {
+	case NR_STATE_0:
+		/* Magic here: If we listen() and a new link dies before it
+		   is accepted() it isn't 'dead' so doesn't get removed. */
+		if (sock_flag(sk, SOCK_DESTROY) ||
+		    (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) {
+			sock_hold(sk);
+			bh_unlock_sock(sk);
+			nr_destroy_socket(sk);
+			sock_put(sk);
+			return;
+		}
+		break;
+
+	case NR_STATE_3:
+		/*
+		 * Check for the state of the receive buffer.
+		 */
+		if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) &&
+		    (nr->condition & NR_COND_OWN_RX_BUSY)) {
+			nr->condition &= ~NR_COND_OWN_RX_BUSY;
+			nr->condition &= ~NR_COND_ACK_PENDING;
+			nr->vl         = nr->vr;
+			nr_write_internal(sk, NR_INFOACK);
+			break;
+		}
+		break;
+	}
+
+	nr_start_heartbeat(sk);
+	bh_unlock_sock(sk);
+}
+
+static void nr_t2timer_expiry(unsigned long param)
+{
+	struct sock *sk = (struct sock *)param;
+	struct nr_sock *nr = nr_sk(sk);
+
+	bh_lock_sock(sk);
+	if (nr->condition & NR_COND_ACK_PENDING) {
+		nr->condition &= ~NR_COND_ACK_PENDING;
+		nr_enquiry_response(sk);
+	}
+	bh_unlock_sock(sk);
+}
+
+static void nr_t4timer_expiry(unsigned long param)
+{
+	struct sock *sk = (struct sock *)param;
+
+	bh_lock_sock(sk);
+	nr_sk(sk)->condition &= ~NR_COND_PEER_RX_BUSY;
+	bh_unlock_sock(sk);
+}
+
+static void nr_idletimer_expiry(unsigned long param)
+{
+	struct sock *sk = (struct sock *)param;
+	struct nr_sock *nr = nr_sk(sk);
+
+	bh_lock_sock(sk);
+
+	nr_clear_queues(sk);
+
+	nr->n2count = 0;
+	nr_write_internal(sk, NR_DISCREQ);
+	nr->state = NR_STATE_2;
+
+	nr_start_t1timer(sk);
+	nr_stop_t2timer(sk);
+	nr_stop_t4timer(sk);
+
+	sk->sk_state     = TCP_CLOSE;
+	sk->sk_err       = 0;
+	sk->sk_shutdown |= SEND_SHUTDOWN;
+
+	if (!sock_flag(sk, SOCK_DEAD)) {
+		sk->sk_state_change(sk);
+		sock_set_flag(sk, SOCK_DEAD);
+	}
+	bh_unlock_sock(sk);
+}
+
+static void nr_t1timer_expiry(unsigned long param)
+{
+	struct sock *sk = (struct sock *)param;
+	struct nr_sock *nr = nr_sk(sk);
+
+	bh_lock_sock(sk);
+	switch (nr->state) {
+	case NR_STATE_1:
+		if (nr->n2count == nr->n2) {
+			nr_disconnect(sk, ETIMEDOUT);
+			bh_unlock_sock(sk);
+			return;
+		} else {
+			nr->n2count++;
+			nr_write_internal(sk, NR_CONNREQ);
+		}
+		break;
+
+	case NR_STATE_2:
+		if (nr->n2count == nr->n2) {
+			nr_disconnect(sk, ETIMEDOUT);
+			bh_unlock_sock(sk);
+			return;
+		} else {
+			nr->n2count++;
+			nr_write_internal(sk, NR_DISCREQ);
+		}
+		break;
+
+	case NR_STATE_3:
+		if (nr->n2count == nr->n2) {
+			nr_disconnect(sk, ETIMEDOUT);
+			bh_unlock_sock(sk);
+			return;
+		} else {
+			nr->n2count++;
+			nr_requeue_frames(sk);
+		}
+		break;
+	}
+
+	nr_start_t1timer(sk);
+	bh_unlock_sock(sk);
+}

net/netrom/sysctl_net_netrom.c

@@ -0,0 +1,157 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Copyright (C) 1996 Mike Shaver (shaver@zeroknowledge.com)
+ */
+#include <linux/mm.h>
+#include <linux/sysctl.h>
+#include <linux/init.h>
+#include <net/ax25.h>
+#include <net/netrom.h>
+
+/*
+ *	Values taken from NET/ROM documentation.
+ */
+static int min_quality[] = {0}, max_quality[] = {255};
+static int min_obs[]     = {0}, max_obs[]     = {255};
+static int min_ttl[]     = {0}, max_ttl[]     = {255};
+static int min_t1[]      = {5 * HZ};
+static int max_t1[]      = {600 * HZ};
+static int min_n2[]      = {2}, max_n2[]      = {127};
+static int min_t2[]      = {1 * HZ};
+static int max_t2[]      = {60 * HZ};
+static int min_t4[]      = {1 * HZ};
+static int max_t4[]      = {1000 * HZ};
+static int min_window[]  = {1}, max_window[]  = {127};
+static int min_idle[]    = {0 * HZ};
+static int max_idle[]    = {65535 * HZ};
+static int min_route[]   = {0}, max_route[]   = {1};
+static int min_fails[]   = {1}, max_fails[]   = {10};
+static int min_reset[]   = {0}, max_reset[]   = {1};
+
+static struct ctl_table_header *nr_table_header;
+
+static struct ctl_table nr_table[] = {
+	{
+		.procname	= "default_path_quality",
+		.data		= &sysctl_netrom_default_path_quality,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_quality,
+		.extra2		= &max_quality
+	},
+	{
+		.procname	= "obsolescence_count_initialiser",
+		.data		= &sysctl_netrom_obsolescence_count_initialiser,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_obs,
+		.extra2		= &max_obs
+	},
+	{
+		.procname	= "network_ttl_initialiser",
+		.data		= &sysctl_netrom_network_ttl_initialiser,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_ttl,
+		.extra2		= &max_ttl
+	},
+	{
+		.procname	= "transport_timeout",
+		.data		= &sysctl_netrom_transport_timeout,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_t1,
+		.extra2		= &max_t1
+	},
+	{
+		.procname	= "transport_maximum_tries",
+		.data		= &sysctl_netrom_transport_maximum_tries,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_n2,
+		.extra2		= &max_n2
+	},
+	{
+		.procname	= "transport_acknowledge_delay",
+		.data		= &sysctl_netrom_transport_acknowledge_delay,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_t2,
+		.extra2		= &max_t2
+	},
+	{
+		.procname	= "transport_busy_delay",
+		.data		= &sysctl_netrom_transport_busy_delay,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_t4,
+		.extra2		= &max_t4
+	},
+	{
+		.procname	= "transport_requested_window_size",
+		.data		= &sysctl_netrom_transport_requested_window_size,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_window,
+		.extra2		= &max_window
+	},
+	{
+		.procname	= "transport_no_activity_timeout",
+		.data		= &sysctl_netrom_transport_no_activity_timeout,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_idle,
+		.extra2		= &max_idle
+	},
+	{
+		.procname	= "routing_control",
+		.data		= &sysctl_netrom_routing_control,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_route,
+		.extra2		= &max_route
+	},
+	{
+		.procname	= "link_fails_count",
+		.data		= &sysctl_netrom_link_fails_count,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_fails,
+		.extra2		= &max_fails
+	},
+	{
+		.procname	= "reset",
+		.data		= &sysctl_netrom_reset_circuit,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &min_reset,
+		.extra2		= &max_reset
+	},
+	{ }
+};
+
+void __init nr_register_sysctl(void)
+{
+	nr_table_header = register_net_sysctl(&init_net, "net/netrom", nr_table);
+}
+
+void nr_unregister_sysctl(void)
+{
+	unregister_net_sysctl_table(nr_table_header);
+}