1/*
  2 * This program is free software; you can redistribute it and/or modify
  3 * it under the terms of the GNU General Public License as published by
  4 * the Free Software Foundation; either version 2 of the License, or
  5 * (at your option) any later version.
  6 *
  7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
  8 */
  9#include <linux/module.h>
 10#include <linux/proc_fs.h>
 11#include <linux/kernel.h>
 12#include <linux/interrupt.h>
 13#include <linux/fs.h>
 14#include <linux/types.h>
 15#include <linux/sysctl.h>
 16#include <linux/string.h>
 17#include <linux/socket.h>
 18#include <linux/errno.h>
 19#include <linux/fcntl.h>
 20#include <linux/in.h>
 21#include <linux/if_ether.h>
 22#include <linux/slab.h>
 23
 24#include <asm/io.h>
 25
 26#include <linux/inet.h>
 27#include <linux/netdevice.h>
 28#include <linux/etherdevice.h>
 29#include <linux/if_arp.h>
 30#include <linux/skbuff.h>
 31
 32#include <net/ip.h>
 33#include <net/arp.h>
 34
 35#include <net/ax25.h>
 36#include <net/rose.h>
 37
 38static int rose_header(struct sk_buff *skb, struct net_device *dev,
 39		       unsigned short type,
 40		       const void *daddr, const void *saddr, unsigned int len)
 41{
 42	unsigned char *buff = skb_push(skb, ROSE_MIN_LEN + 2);
 43
 44	*buff++ = ROSE_GFI | ROSE_Q_BIT;
 45	*buff++ = 0x00;
 46	*buff++ = ROSE_DATA;
 47	*buff++ = 0x7F;
 48	*buff++ = AX25_P_IP;
 49
 50	if (daddr != NULL)
 51		return 37;
 52
 53	return -37;
 54}
 55
 56static int rose_rebuild_header(struct sk_buff *skb)
 57{
 58#ifdef CONFIG_INET
 59	struct net_device *dev = skb->dev;
 60	struct net_device_stats *stats = &dev->stats;
 61	unsigned char *bp = (unsigned char *)skb->data;
 62	struct sk_buff *skbn;
 63	unsigned int len;
 64
 65	if (arp_find(bp + 7, skb)) {
 66		return 1;
 67	}
 68
 69	if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
 70		kfree_skb(skb);
 71		return 1;
 72	}
 73
 74	if (skb->sk != NULL)
 75		skb_set_owner_w(skbn, skb->sk);
 76
 77	kfree_skb(skb);
 78
 79	len = skbn->len;
 80
 81	if (!rose_route_frame(skbn, NULL)) {
 82		kfree_skb(skbn);
 83		stats->tx_errors++;
 84		return 1;
 85	}
 86
 87	stats->tx_packets++;
 88	stats->tx_bytes += len;
 89#endif
 90	return 1;
 91}
 92
 93static int rose_set_mac_address(struct net_device *dev, void *addr)
 94{
 95	struct sockaddr *sa = addr;
 96	int err;
 97
 98	if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len))
 99		return 0;
100
101	if (dev->flags & IFF_UP) {
102		err = rose_add_loopback_node((rose_address *)sa->sa_data);
103		if (err)
104			return err;
105
106		rose_del_loopback_node((rose_address *)dev->dev_addr);
107	}
108
109	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
110
111	return 0;
112}
113
114static int rose_open(struct net_device *dev)
115{
116	int err;
117
118	err = rose_add_loopback_node((rose_address *)dev->dev_addr);
119	if (err)
120		return err;
121
122	netif_start_queue(dev);
123
124	return 0;
125}
126
127static int rose_close(struct net_device *dev)
128{
129	netif_stop_queue(dev);
130	rose_del_loopback_node((rose_address *)dev->dev_addr);
131	return 0;
132}
133
134static netdev_tx_t rose_xmit(struct sk_buff *skb, struct net_device *dev)
135{
136	struct net_device_stats *stats = &dev->stats;
137
138	if (!netif_running(dev)) {
139		printk(KERN_ERR "ROSE: rose_xmit - called when iface is down\n");
140		return NETDEV_TX_BUSY;
141	}
142	dev_kfree_skb(skb);
143	stats->tx_errors++;
144	return NETDEV_TX_OK;
145}
146
147static const struct header_ops rose_header_ops = {
148	.create	= rose_header,
149	.rebuild= rose_rebuild_header,
150};
151
152static const struct net_device_ops rose_netdev_ops = {
153	.ndo_open		= rose_open,
154	.ndo_stop		= rose_close,
155	.ndo_start_xmit		= rose_xmit,
156	.ndo_set_mac_address    = rose_set_mac_address,
157};
158
159void rose_setup(struct net_device *dev)
160{
161	dev->mtu		= ROSE_MAX_PACKET_SIZE - 2;
162	dev->netdev_ops		= &rose_netdev_ops;
163
164	dev->header_ops		= &rose_header_ops;
165	dev->hard_header_len	= AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN;
166	dev->addr_len		= ROSE_ADDR_LEN;
167	dev->type		= ARPHRD_ROSE;
168
169	/* New-style flags. */
170	dev->flags		= IFF_NOARP;
171}