File: /usr/src/linux/net/netrom/nr_dev.c
1 /*
2 * NET/ROM release 007
3 *
4 * This code REQUIRES 2.1.15 or higher/ NET3.038
5 *
6 * This module:
7 * This module is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
12 * History
13 * NET/ROM 001 Jonathan(G4KLX) Cloned from loopback.c
14 * NET/ROM 002 Steve Whitehouse(GW7RRM) fixed the set_mac_address
15 * NET/ROM 003 Jonathan(G4KLX) Put nr_rebuild_header into line with
16 * ax25_rebuild_header
17 * NET/ROM 004 Jonathan(G4KLX) Callsign registration with AX.25.
18 * NET/ROM 006 Hans(PE1AYX) Fixed interface to IP layer.
19 */
20
21 #include <linux/config.h>
22 #define __NO_VERSION__
23 #include <linux/module.h>
24 #include <linux/proc_fs.h>
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <linux/interrupt.h>
28 #include <linux/fs.h>
29 #include <linux/types.h>
30 #include <linux/sysctl.h>
31 #include <linux/string.h>
32 #include <linux/socket.h>
33 #include <linux/errno.h>
34 #include <linux/fcntl.h>
35 #include <linux/in.h>
36 #include <linux/if_ether.h> /* For the statistics structure. */
37
38 #include <asm/system.h>
39 #include <asm/uaccess.h>
40 #include <asm/io.h>
41
42 #include <linux/inet.h>
43 #include <linux/netdevice.h>
44 #include <linux/etherdevice.h>
45 #include <linux/if_arp.h>
46 #include <linux/skbuff.h>
47
48 #include <net/ip.h>
49 #include <net/arp.h>
50
51 #include <net/ax25.h>
52 #include <net/netrom.h>
53
54 #ifdef CONFIG_INET
55
56 /*
57 * Only allow IP over NET/ROM frames through if the netrom device is up.
58 */
59
60 int nr_rx_ip(struct sk_buff *skb, struct net_device *dev)
61 {
62 struct net_device_stats *stats = (struct net_device_stats *)dev->priv;
63
64 if (!netif_running(dev)) {
65 stats->rx_errors++;
66 return 0;
67 }
68
69 stats->rx_packets++;
70 stats->rx_bytes += skb->len;
71
72 skb->protocol = htons(ETH_P_IP);
73
74 /* Spoof incoming device */
75 skb->dev = dev;
76 skb->h.raw = skb->data;
77 skb->nh.raw = skb->data;
78 skb->pkt_type = PACKET_HOST;
79
80 ip_rcv(skb, skb->dev, NULL);
81
82 return 1;
83 }
84
85
86 static int nr_rebuild_header(struct sk_buff *skb)
87 {
88 struct net_device *dev = skb->dev;
89 struct net_device_stats *stats = (struct net_device_stats *)dev->priv;
90 struct sk_buff *skbn;
91 unsigned char *bp = skb->data;
92 int len;
93
94 if (arp_find(bp + 7, skb)) {
95 return 1;
96 }
97
98 bp[6] &= ~AX25_CBIT;
99 bp[6] &= ~AX25_EBIT;
100 bp[6] |= AX25_SSSID_SPARE;
101 bp += AX25_ADDR_LEN;
102
103 bp[6] &= ~AX25_CBIT;
104 bp[6] |= AX25_EBIT;
105 bp[6] |= AX25_SSSID_SPARE;
106
107 if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
108 kfree_skb(skb);
109 return 1;
110 }
111
112 if (skb->sk != NULL)
113 skb_set_owner_w(skbn, skb->sk);
114
115 kfree_skb(skb);
116
117 len = skbn->len;
118
119 if (!nr_route_frame(skbn, NULL)) {
120 kfree_skb(skbn);
121 stats->tx_errors++;
122 }
123
124 stats->tx_packets++;
125 stats->tx_bytes += len;
126
127 return 1;
128 }
129
130 #else
131
132 static int nr_rebuild_header(struct sk_buff *skb)
133 {
134 return 1;
135 }
136
137 #endif
138
139 static int nr_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
140 void *daddr, void *saddr, unsigned len)
141 {
142 unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
143
144 memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len);
145 buff[6] &= ~AX25_CBIT;
146 buff[6] &= ~AX25_EBIT;
147 buff[6] |= AX25_SSSID_SPARE;
148 buff += AX25_ADDR_LEN;
149
150 if (daddr != NULL)
151 memcpy(buff, daddr, dev->addr_len);
152 buff[6] &= ~AX25_CBIT;
153 buff[6] |= AX25_EBIT;
154 buff[6] |= AX25_SSSID_SPARE;
155 buff += AX25_ADDR_LEN;
156
157 *buff++ = sysctl_netrom_network_ttl_initialiser;
158
159 *buff++ = NR_PROTO_IP;
160 *buff++ = NR_PROTO_IP;
161 *buff++ = 0;
162 *buff++ = 0;
163 *buff++ = NR_PROTOEXT;
164
165 if (daddr != NULL)
166 return 37;
167
168 return -37;
169 }
170
171 static int nr_set_mac_address(struct net_device *dev, void *addr)
172 {
173 struct sockaddr *sa = addr;
174
175 ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
176
177 memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
178
179 ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
180
181 return 0;
182 }
183
184 static int nr_open(struct net_device *dev)
185 {
186 MOD_INC_USE_COUNT;
187 netif_start_queue(dev);
188 ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
189 return 0;
190 }
191
192 static int nr_close(struct net_device *dev)
193 {
194 netif_stop_queue(dev);
195 ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
196 MOD_DEC_USE_COUNT;
197 return 0;
198 }
199
200 static int nr_xmit(struct sk_buff *skb, struct net_device *dev)
201 {
202 struct net_device_stats *stats = (struct net_device_stats *)dev->priv;
203 dev_kfree_skb(skb);
204 stats->tx_errors++;
205 return 0;
206 }
207
208 static struct net_device_stats *nr_get_stats(struct net_device *dev)
209 {
210 return (struct net_device_stats *)dev->priv;
211 }
212
213 int nr_init(struct net_device *dev)
214 {
215 dev->mtu = NR_MAX_PACKET_SIZE;
216 dev->hard_start_xmit = nr_xmit;
217 dev->open = nr_open;
218 dev->stop = nr_close;
219
220 dev->hard_header = nr_header;
221 dev->hard_header_len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + NR_NETWORK_LEN + NR_TRANSPORT_LEN;
222 dev->addr_len = AX25_ADDR_LEN;
223 dev->type = ARPHRD_NETROM;
224 dev->rebuild_header = nr_rebuild_header;
225 dev->set_mac_address = nr_set_mac_address;
226
227 /* New-style flags. */
228 dev->flags = 0;
229
230 if ((dev->priv = kmalloc(sizeof(struct net_device_stats), GFP_KERNEL)) == NULL)
231 return -ENOMEM;
232
233 memset(dev->priv, 0, sizeof(struct net_device_stats));
234
235 dev->get_stats = nr_get_stats;
236
237 return 0;
238 };
239