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 #include <linux/slab.h>
  23
  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,
  39                        unsigned short type,
  40                        const void *daddr, const void *saddr, unsigned int len)
  41 {
  42         unsigned char *buff = skb_push(skb, ROSE_MIN_LEN + 2);
  43
  44         *buff++ = ROSE_GFI | ROSE_Q_BIT;
  45         *buff++ = 0x00;
  46         *buff++ = ROSE_DATA;
  47         *buff++ = 0x7F;
  48         *buff++ = AX25_P_IP;
  49
  50         if (daddr != NULL)
  51                 return 37;
  52
  53         return -37;
  54 }
  55
  56 static int rose_rebuild_header(struct sk_buff *skb)
  57 {
  58 #ifdef CONFIG_INET
  59         struct net_device *dev = skb->dev;
  60         struct net_device_stats *stats = &dev->stats;
  61         unsigned char *bp = (unsigned char *)skb->data;
  62         struct sk_buff *skbn;
  63         unsigned int len;
  64
  65         if (arp_find(bp + 7, skb)) {
  66                 return 1;
  67         }
  68
  69         if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
  70                 kfree_skb(skb);
  71                 return 1;
  72         }
  73
  74         if (skb->sk != NULL)
  75                 skb_set_owner_w(skbn, skb->sk);
  76
  77         kfree_skb(skb);
  78
  79         len = skbn->len;
  80
  81         if (!rose_route_frame(skbn, NULL)) {
  82                 kfree_skb(skbn);
  83                 stats->tx_errors++;
  84                 return 1;
  85         }
  86
  87         stats->tx_packets++;
  88         stats->tx_bytes += len;
  89 #endif
  90         return 1;
  91 }
  92
  93 static int rose_set_mac_address(struct net_device *dev, void *addr)
  94 {
  95         struct sockaddr *sa = addr;
  96         int err;
  97
  98         if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len))
  99                 return 0;
 100
 101         if (dev->flags & IFF_UP) {
 102                 err = rose_add_loopback_node((rose_address *)sa->sa_data);
 103                 if (err)
 104                         return err;
 105
 106                 rose_del_loopback_node((rose_address *)dev->dev_addr);
 107         }
 108
 109         memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
 110
 111         return 0;
 112 }
 113
 114 static int rose_open(struct net_device *dev)
 115 {
 116         int err;
 117
 118         err = rose_add_loopback_node((rose_address *)dev->dev_addr);
 119         if (err)
 120                 return err;
 121
 122         netif_start_queue(dev);
 123
 124         return 0;
 125 }
 126
 127 static int rose_close(struct net_device *dev)
 128 {
 129         netif_stop_queue(dev);
 130         rose_del_loopback_node((rose_address *)dev->dev_addr);
 131         return 0;
 132 }
 133
 134 static netdev_tx_t rose_xmit(struct sk_buff *skb, struct net_device *dev)
 135 {
 136         struct net_device_stats *stats = &dev->stats;
 137
 138         if (!netif_running(dev)) {
 139                 printk(KERN_ERR "ROSE: rose_xmit - called when iface is down\n");
 140                 return NETDEV_TX_BUSY;
 141         }
 142         dev_kfree_skb(skb);
 143         stats->tx_errors++;
 144         return NETDEV_TX_OK;
 145 }
 146
 147 static const struct header_ops rose_header_ops = {
 148         .create = rose_header,
 149         .rebuild= rose_rebuild_header,
 150 };
 151
 152 static const struct net_device_ops rose_netdev_ops = {
 153         .ndo_open               = rose_open,
 154         .ndo_stop               = rose_close,
 155         .ndo_start_xmit         = rose_xmit,
 156         .ndo_set_mac_address    = rose_set_mac_address,
 157 };
 158
 159 void rose_setup(struct net_device *dev)
 160 {
 161         dev->mtu                = ROSE_MAX_PACKET_SIZE - 2;
 162         dev->netdev_ops         = &rose_netdev_ops;
 163
 164         dev->header_ops         = &rose_header_ops;
 165         dev->hard_header_len    = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN;
 166         dev->addr_len           = ROSE_ADDR_LEN;
 167         dev->type               = ARPHRD_ROSE;
 168
 169         /* New-style flags. */
 170         dev->flags              = IFF_NOARP;
 171 }