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 Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) 8 */ 9 #include <linux/config.h> 10 #include <linux/module.h> 11 #include <linux/proc_fs.h> 12 #include <linux/kernel.h> 13 #include <linux/sched.h> 14 #include <linux/interrupt.h> 15 #include <linux/fs.h> 16 #include <linux/types.h> 17 #include <linux/sysctl.h> 18 #include <linux/string.h> 19 #include <linux/socket.h> 20 #include <linux/errno.h> 21 #include <linux/fcntl.h> 22 #include <linux/in.h> 23 #include <linux/if_ether.h> /* For the statistics structure. */ 24 25 #include <asm/system.h> 26 #include <asm/uaccess.h> 27 #include <asm/io.h> 28 29 #include <linux/inet.h> 30 #include <linux/netdevice.h> 31 #include <linux/etherdevice.h> 32 #include <linux/if_arp.h> 33 #include <linux/skbuff.h> 34 35 #include <net/ip.h> 36 #include <net/arp.h> 37 38 #include <net/ax25.h> 39 #include <net/netrom.h> 40 41 /* 42 * Only allow IP over NET/ROM frames through if the netrom device is up. 43 */ 44 45 int nr_rx_ip(struct sk_buff *skb, struct net_device *dev) 46 { 47 struct net_device_stats *stats = netdev_priv(dev); 48 49 if (!netif_running(dev)) { 50 stats->rx_errors++; 51 return 0; 52 } 53 54 stats->rx_packets++; 55 stats->rx_bytes += skb->len; 56 57 skb->protocol = htons(ETH_P_IP); 58 59 /* Spoof incoming device */ 60 skb->dev = dev; 61 skb->h.raw = skb->data; 62 skb->nh.raw = skb->data; 63 skb->pkt_type = PACKET_HOST; 64 65 netif_rx(skb); 66 67 return 1; 68 } 69 70 #ifdef CONFIG_INET 71 72 static int nr_rebuild_header(struct sk_buff *skb) 73 { 74 struct net_device *dev = skb->dev; 75 struct net_device_stats *stats = netdev_priv(dev); 76 struct sk_buff *skbn; 77 unsigned char *bp = skb->data; 78 int len; 79 80 if (arp_find(bp + 7, skb)) { 81 return 1; 82 } 83 84 bp[6] &= ~AX25_CBIT; 85 bp[6] &= ~AX25_EBIT; 86 bp[6] |= AX25_SSSID_SPARE; 87 bp += AX25_ADDR_LEN; 88 89 bp[6] &= ~AX25_CBIT; 90 bp[6] |= AX25_EBIT; 91 bp[6] |= AX25_SSSID_SPARE; 92 93 if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) { 94 kfree_skb(skb); 95 return 1; 96 } 97 98 if (skb->sk != NULL) 99 skb_set_owner_w(skbn, skb->sk); 100 101 kfree_skb(skb); 102 103 len = skbn->len; 104 105 if (!nr_route_frame(skbn, NULL)) { 106 kfree_skb(skbn); 107 stats->tx_errors++; 108 } 109 110 stats->tx_packets++; 111 stats->tx_bytes += len; 112 113 return 1; 114 } 115 116 #else 117 118 static int nr_rebuild_header(struct sk_buff *skb) 119 { 120 return 1; 121 } 122 123 #endif 124 125 static int nr_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, 126 void *daddr, void *saddr, unsigned len) 127 { 128 unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN); 129 130 memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len); 131 buff[6] &= ~AX25_CBIT; 132 buff[6] &= ~AX25_EBIT; 133 buff[6] |= AX25_SSSID_SPARE; 134 buff += AX25_ADDR_LEN; 135 136 if (daddr != NULL) 137 memcpy(buff, daddr, dev->addr_len); 138 buff[6] &= ~AX25_CBIT; 139 buff[6] |= AX25_EBIT; 140 buff[6] |= AX25_SSSID_SPARE; 141 buff += AX25_ADDR_LEN; 142 143 *buff++ = sysctl_netrom_network_ttl_initialiser; 144 145 *buff++ = NR_PROTO_IP; 146 *buff++ = NR_PROTO_IP; 147 *buff++ = 0; 148 *buff++ = 0; 149 *buff++ = NR_PROTOEXT; 150 151 if (daddr != NULL) 152 return 37; 153 154 return -37; 155 } 156 157 static int nr_set_mac_address(struct net_device *dev, void *addr) 158 { 159 struct sockaddr *sa = addr; 160 161 if (dev->flags & IFF_UP) 162 ax25_listen_release((ax25_address *)dev->dev_addr, NULL); 163 164 memcpy(dev->dev_addr, sa->sa_data, dev->addr_len); 165 166 if (dev->flags & IFF_UP) 167 ax25_listen_register((ax25_address *)dev->dev_addr, NULL); 168 169 return 0; 170 } 171 172 static int nr_open(struct net_device *dev) 173 { 174 netif_start_queue(dev); 175 ax25_listen_register((ax25_address *)dev->dev_addr, NULL); 176 return 0; 177 } 178 179 static int nr_close(struct net_device *dev) 180 { 181 ax25_listen_release((ax25_address *)dev->dev_addr, NULL); 182 netif_stop_queue(dev); 183 return 0; 184 } 185 186 static int nr_xmit(struct sk_buff *skb, struct net_device *dev) 187 { 188 struct net_device_stats *stats = netdev_priv(dev); 189 dev_kfree_skb(skb); 190 stats->tx_errors++; 191 return 0; 192 } 193 194 static struct net_device_stats *nr_get_stats(struct net_device *dev) 195 { 196 return netdev_priv(dev); 197 } 198 199 void nr_setup(struct net_device *dev) 200 { 201 SET_MODULE_OWNER(dev); 202 dev->mtu = NR_MAX_PACKET_SIZE; 203 dev->hard_start_xmit = nr_xmit; 204 dev->open = nr_open; 205 dev->stop = nr_close; 206 207 dev->hard_header = nr_header; 208 dev->hard_header_len = NR_NETWORK_LEN + NR_TRANSPORT_LEN; 209 dev->addr_len = AX25_ADDR_LEN; 210 dev->type = ARPHRD_NETROM; 211 dev->tx_queue_len = 40; 212 dev->rebuild_header = nr_rebuild_header; 213 dev->set_mac_address = nr_set_mac_address; 214 215 /* New-style flags. */ 216 dev->flags = 0; 217 218 dev->get_stats = nr_get_stats; 219 } 220