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/system.h>
  25 #include <asm/io.h>
  26
  27 #include <linux/inet.h>
  28 #include <linux/netdevice.h>
  29 #include <linux/etherdevice.h>
  30 #include <linux/if_arp.h>
  31 #include <linux/skbuff.h>
  32
  33 #include <net/ip.h>
  34 #include <net/arp.h>
  35
  36 #include <net/ax25.h>
  37 #include <net/rose.h>
  38
  39 static int rose_header(struct sk_buff *skb, struct net_device *dev,
  40                        unsigned short type,
  41                        const void *daddr, const void *saddr, unsigned len)
  42 {
  43         unsigned char *buff = skb_push(skb, ROSE_MIN_LEN + 2);
  44
  45         *buff++ = ROSE_GFI | ROSE_Q_BIT;
  46         *buff++ = 0x00;
  47         *buff++ = ROSE_DATA;
  48         *buff++ = 0x7F;
  49         *buff++ = AX25_P_IP;
  50
  51         if (daddr != NULL)
  52                 return 37;
  53
  54         return -37;
  55 }
  56
  57 static int rose_rebuild_header(struct sk_buff *skb)
  58 {
  59 #ifdef CONFIG_INET
  60         struct net_device *dev = skb->dev;
  61         struct net_device_stats *stats = &dev->stats;
  62         unsigned char *bp = (unsigned char *)skb->data;
  63         struct sk_buff *skbn;
  64         unsigned int len;
  65
  66         if (arp_find(bp + 7, skb)) {
  67                 return 1;
  68         }
  69
  70         if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
  71                 kfree_skb(skb);
  72                 return 1;
  73         }
  74
  75         if (skb->sk != NULL)
  76                 skb_set_owner_w(skbn, skb->sk);
  77
  78         kfree_skb(skb);
  79
  80         len = skbn->len;
  81
  82         if (!rose_route_frame(skbn, NULL)) {
  83                 kfree_skb(skbn);
  84                 stats->tx_errors++;
  85                 return 1;
  86         }
  87
  88         stats->tx_packets++;
  89         stats->tx_bytes += len;
  90 #endif
  91         return 1;
  92 }
  93
  94 static int rose_set_mac_address(struct net_device *dev, void *addr)
  95 {
  96         struct sockaddr *sa = addr;
  97         int err;
  98
  99         if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len))
 100                 return 0;
 101
 102         if (dev->flags & IFF_UP) {
 103                 err = rose_add_loopback_node((rose_address *)sa->sa_data);
 104                 if (err)
 105                         return err;
 106
 107                 rose_del_loopback_node((rose_address *)dev->dev_addr);
 108         }
 109
 110         memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
 111
 112         return 0;
 113 }
 114
 115 static int rose_open(struct net_device *dev)
 116 {
 117         int err;
 118
 119         err = rose_add_loopback_node((rose_address *)dev->dev_addr);
 120         if (err)
 121                 return err;
 122
 123         netif_start_queue(dev);
 124
 125         return 0;
 126 }
 127
 128 static int rose_close(struct net_device *dev)
 129 {
 130         netif_stop_queue(dev);
 131         rose_del_loopback_node((rose_address *)dev->dev_addr);
 132         return 0;
 133 }
 134
 135 static netdev_tx_t rose_xmit(struct sk_buff *skb, struct net_device *dev)
 136 {
 137         struct net_device_stats *stats = &dev->stats;
 138
 139         if (!netif_running(dev)) {
 140                 printk(KERN_ERR "ROSE: rose_xmit - called when iface is down\n");
 141                 return NETDEV_TX_BUSY;
 142         }
 143         dev_kfree_skb(skb);
 144         stats->tx_errors++;
 145         return NETDEV_TX_OK;
 146 }
 147
 148 static const struct header_ops rose_header_ops = {
 149         .create = rose_header,
 150         .rebuild= rose_rebuild_header,
 151 };
 152
 153 static const struct net_device_ops rose_netdev_ops = {
 154         .ndo_open               = rose_open,
 155         .ndo_stop               = rose_close,
 156         .ndo_start_xmit         = rose_xmit,
 157         .ndo_set_mac_address    = rose_set_mac_address,
 158 };
 159
 160 void rose_setup(struct net_device *dev)
 161 {
 162         dev->mtu                = ROSE_MAX_PACKET_SIZE - 2;
 163         dev->netdev_ops         = &rose_netdev_ops;
 164
 165         dev->header_ops         = &rose_header_ops;
 166         dev->hard_header_len    = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN;
 167         dev->addr_len           = ROSE_ADDR_LEN;
 168         dev->type               = ARPHRD_ROSE;
 169
 170         /* New-style flags. */
 171         dev->flags              = IFF_NOARP;
 172 }