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_dropped++; 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->mac.raw = skb->nh.raw; 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 unsigned char *bp = skb->data; 75 76 if (arp_find(bp + 7, skb)) 77 return 1; 78 79 bp[6] &= ~AX25_CBIT; 80 bp[6] &= ~AX25_EBIT; 81 bp[6] |= AX25_SSSID_SPARE; 82 bp += AX25_ADDR_LEN; 83 84 bp[6] &= ~AX25_CBIT; 85 bp[6] |= AX25_EBIT; 86 bp[6] |= AX25_SSSID_SPARE; 87 88 return 0; 89 } 90 91 #else 92 93 static int nr_rebuild_header(struct sk_buff *skb) 94 { 95 return 1; 96 } 97 98 #endif 99 100 static int nr_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, 101 void *daddr, void *saddr, unsigned len) 102 { 103 unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN); 104 105 memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len); 106 buff[6] &= ~AX25_CBIT; 107 buff[6] &= ~AX25_EBIT; 108 buff[6] |= AX25_SSSID_SPARE; 109 buff += AX25_ADDR_LEN; 110 111 if (daddr != NULL) 112 memcpy(buff, daddr, dev->addr_len); 113 buff[6] &= ~AX25_CBIT; 114 buff[6] |= AX25_EBIT; 115 buff[6] |= AX25_SSSID_SPARE; 116 buff += AX25_ADDR_LEN; 117 118 *buff++ = sysctl_netrom_network_ttl_initialiser; 119 120 *buff++ = NR_PROTO_IP; 121 *buff++ = NR_PROTO_IP; 122 *buff++ = 0; 123 *buff++ = 0; 124 *buff++ = NR_PROTOEXT; 125 126 if (daddr != NULL) 127 return 37; 128 129 return -37; 130 } 131 132 static int nr_set_mac_address(struct net_device *dev, void *addr) 133 { 134 struct sockaddr *sa = addr; 135 136 if (dev->flags & IFF_UP) 137 ax25_listen_release((ax25_address *)dev->dev_addr, NULL); 138 139 memcpy(dev->dev_addr, sa->sa_data, dev->addr_len); 140 141 if (dev->flags & IFF_UP) 142 ax25_listen_register((ax25_address *)dev->dev_addr, NULL); 143 144 return 0; 145 } 146 147 static int nr_open(struct net_device *dev) 148 { 149 netif_start_queue(dev); 150 ax25_listen_register((ax25_address *)dev->dev_addr, NULL); 151 return 0; 152 } 153 154 static int nr_close(struct net_device *dev) 155 { 156 ax25_listen_release((ax25_address *)dev->dev_addr, NULL); 157 netif_stop_queue(dev); 158 return 0; 159 } 160 161 static int nr_xmit(struct sk_buff *skb, struct net_device *dev) 162 { 163 struct nr_private *nr = netdev_priv(dev); 164 struct net_device_stats *stats = &nr->stats; 165 unsigned int len = skb->len; 166 167 if (!nr_route_frame(skb, NULL)) { 168 kfree_skb(skb); 169 stats->tx_errors++; 170 return 0; 171 } 172 173 stats->tx_packets++; 174 stats->tx_bytes += len; 175 176 return 0; 177 } 178 179 static struct net_device_stats *nr_get_stats(struct net_device *dev) 180 { 181 struct nr_private *nr = netdev_priv(dev); 182 183 return &nr->stats; 184 } 185 186 void nr_setup(struct net_device *dev) 187 { 188 SET_MODULE_OWNER(dev); 189 dev->mtu = NR_MAX_PACKET_SIZE; 190 dev->hard_start_xmit = nr_xmit; 191 dev->open = nr_open; 192 dev->stop = nr_close; 193 194 dev->hard_header = nr_header; 195 dev->hard_header_len = NR_NETWORK_LEN + NR_TRANSPORT_LEN; 196 dev->addr_len = AX25_ADDR_LEN; 197 dev->type = ARPHRD_NETROM; 198 dev->rebuild_header = nr_rebuild_header; 199 dev->set_mac_address = nr_set_mac_address; 200 201 /* New-style flags. */ 202 dev->flags = IFF_NOARP; 203 204 dev->get_stats = nr_get_stats; 205 } 206