xref: /linux/net/rose/rose_dev.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
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 
23 #include <asm/system.h>
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 
38 static int rose_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
39 	void *daddr, void *saddr, unsigned len)
40 {
41 	unsigned char *buff = skb_push(skb, ROSE_MIN_LEN + 2);
42 
43 	*buff++ = ROSE_GFI | ROSE_Q_BIT;
44 	*buff++ = 0x00;
45 	*buff++ = ROSE_DATA;
46 	*buff++ = 0x7F;
47 	*buff++ = AX25_P_IP;
48 
49 	if (daddr != NULL)
50 		return 37;
51 
52 	return -37;
53 }
54 
55 static int rose_rebuild_header(struct sk_buff *skb)
56 {
57 	struct net_device *dev = skb->dev;
58 	struct net_device_stats *stats = netdev_priv(dev);
59 	unsigned char *bp = (unsigned char *)skb->data;
60 	struct sk_buff *skbn;
61 	unsigned int len;
62 
63 #ifdef CONFIG_INET
64 	if (arp_find(bp + 7, skb)) {
65 		return 1;
66 	}
67 
68 	if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
69 		kfree_skb(skb);
70 		return 1;
71 	}
72 
73 	if (skb->sk != NULL)
74 		skb_set_owner_w(skbn, skb->sk);
75 
76 	kfree_skb(skb);
77 
78 	len = skbn->len;
79 
80 	if (!rose_route_frame(skbn, NULL)) {
81 		kfree_skb(skbn);
82 		stats->tx_errors++;
83 		return 1;
84 	}
85 
86 	stats->tx_packets++;
87 	stats->tx_bytes += len;
88 #endif
89 	return 1;
90 }
91 
92 static int rose_set_mac_address(struct net_device *dev, void *addr)
93 {
94 	struct sockaddr *sa = addr;
95 	int err;
96 
97 	if (!memcpy(dev->dev_addr, sa->sa_data, dev->addr_len))
98 		return 0;
99 
100 	if (dev->flags & IFF_UP) {
101 		err = rose_add_loopback_node((rose_address *)dev->dev_addr);
102 		if (err)
103 			return err;
104 
105 		rose_del_loopback_node((rose_address *)dev->dev_addr);
106 	}
107 
108 	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
109 
110 	return 0;
111 }
112 
113 static int rose_open(struct net_device *dev)
114 {
115 	int err;
116 
117 	err = rose_add_loopback_node((rose_address *)dev->dev_addr);
118 	if (err)
119 		return err;
120 
121 	netif_start_queue(dev);
122 
123 	return 0;
124 }
125 
126 static int rose_close(struct net_device *dev)
127 {
128 	netif_stop_queue(dev);
129 	rose_del_loopback_node((rose_address *)dev->dev_addr);
130 	return 0;
131 }
132 
133 static int rose_xmit(struct sk_buff *skb, struct net_device *dev)
134 {
135 	struct net_device_stats *stats = netdev_priv(dev);
136 
137 	if (!netif_running(dev)) {
138 		printk(KERN_ERR "ROSE: rose_xmit - called when iface is down\n");
139 		return 1;
140 	}
141 	dev_kfree_skb(skb);
142 	stats->tx_errors++;
143 	return 0;
144 }
145 
146 static struct net_device_stats *rose_get_stats(struct net_device *dev)
147 {
148 	return netdev_priv(dev);
149 }
150 
151 void rose_setup(struct net_device *dev)
152 {
153 	dev->mtu		= ROSE_MAX_PACKET_SIZE - 2;
154 	dev->hard_start_xmit	= rose_xmit;
155 	dev->open		= rose_open;
156 	dev->stop		= rose_close;
157 
158 	dev->hard_header	= rose_header;
159 	dev->hard_header_len	= AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN;
160 	dev->addr_len		= ROSE_ADDR_LEN;
161 	dev->type		= ARPHRD_ROSE;
162 	dev->rebuild_header	= rose_rebuild_header;
163 	dev->set_mac_address    = rose_set_mac_address;
164 
165 	/* New-style flags. */
166 	dev->flags		= IFF_NOARP;
167 	dev->get_stats = rose_get_stats;
168 }
169