net/rose/rose_dev.c

   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 }