linux/net/netrom/nr_dev.c
<<
>>
Prefs
   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/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>     /* For the statistics structure. */
  22#include <linux/slab.h>
  23
  24#include <asm/uaccess.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/netrom.h>
  38
  39/*
  40 *      Only allow IP over NET/ROM frames through if the netrom device is up.
  41 */
  42
  43int nr_rx_ip(struct sk_buff *skb, struct net_device *dev)
  44{
  45        struct net_device_stats *stats = &dev->stats;
  46
  47        if (!netif_running(dev)) {
  48                stats->rx_dropped++;
  49                return 0;
  50        }
  51
  52        stats->rx_packets++;
  53        stats->rx_bytes += skb->len;
  54
  55        skb->protocol = htons(ETH_P_IP);
  56
  57        /* Spoof incoming device */
  58        skb->dev      = dev;
  59        skb->mac_header = skb->network_header;
  60        skb_reset_network_header(skb);
  61        skb->pkt_type = PACKET_HOST;
  62
  63        netif_rx(skb);
  64
  65        return 1;
  66}
  67
  68#ifdef CONFIG_INET
  69
  70static int nr_rebuild_header(struct sk_buff *skb)
  71{
  72        unsigned char *bp = skb->data;
  73
  74        if (arp_find(bp + 7, skb))
  75                return 1;
  76
  77        bp[6] &= ~AX25_CBIT;
  78        bp[6] &= ~AX25_EBIT;
  79        bp[6] |= AX25_SSSID_SPARE;
  80        bp    += AX25_ADDR_LEN;
  81
  82        bp[6] &= ~AX25_CBIT;
  83        bp[6] |= AX25_EBIT;
  84        bp[6] |= AX25_SSSID_SPARE;
  85
  86        return 0;
  87}
  88
  89#else
  90
  91static int nr_rebuild_header(struct sk_buff *skb)
  92{
  93        return 1;
  94}
  95
  96#endif
  97
  98static int nr_header(struct sk_buff *skb, struct net_device *dev,
  99                     unsigned short type,
 100                     const void *daddr, const void *saddr, unsigned int len)
 101{
 102        unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
 103
 104        memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len);
 105        buff[6] &= ~AX25_CBIT;
 106        buff[6] &= ~AX25_EBIT;
 107        buff[6] |= AX25_SSSID_SPARE;
 108        buff    += AX25_ADDR_LEN;
 109
 110        if (daddr != NULL)
 111                memcpy(buff, daddr, dev->addr_len);
 112        buff[6] &= ~AX25_CBIT;
 113        buff[6] |= AX25_EBIT;
 114        buff[6] |= AX25_SSSID_SPARE;
 115        buff    += AX25_ADDR_LEN;
 116
 117        *buff++ = sysctl_netrom_network_ttl_initialiser;
 118
 119        *buff++ = NR_PROTO_IP;
 120        *buff++ = NR_PROTO_IP;
 121        *buff++ = 0;
 122        *buff++ = 0;
 123        *buff++ = NR_PROTOEXT;
 124
 125        if (daddr != NULL)
 126                return 37;
 127
 128        return -37;
 129}
 130
 131static int __must_check nr_set_mac_address(struct net_device *dev, void *addr)
 132{
 133        struct sockaddr *sa = addr;
 134        int err;
 135
 136        if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len))
 137                return 0;
 138
 139        if (dev->flags & IFF_UP) {
 140                err = ax25_listen_register((ax25_address *)sa->sa_data, NULL);
 141                if (err)
 142                        return err;
 143
 144                ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
 145        }
 146
 147        memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
 148
 149        return 0;
 150}
 151
 152static int nr_open(struct net_device *dev)
 153{
 154        int err;
 155
 156        err = ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
 157        if (err)
 158                return err;
 159
 160        netif_start_queue(dev);
 161
 162        return 0;
 163}
 164
 165static int nr_close(struct net_device *dev)
 166{
 167        ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
 168        netif_stop_queue(dev);
 169        return 0;
 170}
 171
 172static netdev_tx_t nr_xmit(struct sk_buff *skb, struct net_device *dev)
 173{
 174        struct net_device_stats *stats = &dev->stats;
 175        unsigned int len = skb->len;
 176
 177        if (!nr_route_frame(skb, NULL)) {
 178                kfree_skb(skb);
 179                stats->tx_errors++;
 180                return NETDEV_TX_OK;
 181        }
 182
 183        stats->tx_packets++;
 184        stats->tx_bytes += len;
 185
 186        return NETDEV_TX_OK;
 187}
 188
 189static const struct header_ops nr_header_ops = {
 190        .create = nr_header,
 191        .rebuild= nr_rebuild_header,
 192};
 193
 194static const struct net_device_ops nr_netdev_ops = {
 195        .ndo_open               = nr_open,
 196        .ndo_stop               = nr_close,
 197        .ndo_start_xmit         = nr_xmit,
 198        .ndo_set_mac_address    = nr_set_mac_address,
 199};
 200
 201void nr_setup(struct net_device *dev)
 202{
 203        dev->mtu                = NR_MAX_PACKET_SIZE;
 204        dev->netdev_ops         = &nr_netdev_ops;
 205        dev->header_ops         = &nr_header_ops;
 206        dev->hard_header_len    = NR_NETWORK_LEN + NR_TRANSPORT_LEN;
 207        dev->addr_len           = AX25_ADDR_LEN;
 208        dev->type               = ARPHRD_NETROM;
 209
 210        /* New-style flags. */
 211        dev->flags              = IFF_NOARP;
 212}
 213
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.