LXR linux/net/netrom/nr

   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#include <linux/uaccess.h>
  24
  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
  68static int nr_header(struct sk_buff *skb, struct net_device *dev,
  69                     unsigned short type,
  70                     const void *daddr, const void *saddr, unsigned int len)
  71{
  72        unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
  73
  74        memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len);
  75        buff[6] &= ~AX25_CBIT;
  76        buff[6] &= ~AX25_EBIT;
  77        buff[6] |= AX25_SSSID_SPARE;
  78        buff    += AX25_ADDR_LEN;
  79
  80        if (daddr != NULL)
  81                memcpy(buff, daddr, dev->addr_len);
  82        buff[6] &= ~AX25_CBIT;
  83        buff[6] |= AX25_EBIT;
  84        buff[6] |= AX25_SSSID_SPARE;
  85        buff    += AX25_ADDR_LEN;
  86
  87        *buff++ = sysctl_netrom_network_ttl_initialiser;
  88
  89        *buff++ = NR_PROTO_IP;
  90        *buff++ = NR_PROTO_IP;
  91        *buff++ = 0;
  92        *buff++ = 0;
  93        *buff++ = NR_PROTOEXT;
  94
  95        if (daddr != NULL)
  96                return 37;
  97
  98        return -37;
  99}
 100
 101static int __must_check nr_set_mac_address(struct net_device *dev, void *addr)
 102{
 103        struct sockaddr *sa = addr;
 104        int err;
 105
 106        if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len))
 107                return 0;
 108
 109        if (dev->flags & IFF_UP) {
 110                err = ax25_listen_register((ax25_address *)sa->sa_data, NULL);
 111                if (err)
 112                        return err;
 113
 114                ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
 115        }
 116
 117        memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
 118
 119        return 0;
 120}
 121
 122static int nr_open(struct net_device *dev)
 123{
 124        int err;
 125
 126        err = ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
 127        if (err)
 128                return err;
 129
 130        netif_start_queue(dev);
 131
 132        return 0;
 133}
 134
 135static int nr_close(struct net_device *dev)
 136{
 137        ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
 138        netif_stop_queue(dev);
 139        return 0;
 140}
 141
 142static netdev_tx_t nr_xmit(struct sk_buff *skb, struct net_device *dev)
 143{
 144        struct net_device_stats *stats = &dev->stats;
 145        unsigned int len = skb->len;
 146
 147        if (!nr_route_frame(skb, NULL)) {
 148                kfree_skb(skb);
 149                stats->tx_errors++;
 150                return NETDEV_TX_OK;
 151        }
 152
 153        stats->tx_packets++;
 154        stats->tx_bytes += len;
 155
 156        return NETDEV_TX_OK;
 157}
 158
 159static const struct header_ops nr_header_ops = {
 160        .create = nr_header,
 161};
 162
 163static const struct net_device_ops nr_netdev_ops = {
 164        .ndo_open               = nr_open,
 165        .ndo_stop               = nr_close,
 166        .ndo_start_xmit         = nr_xmit,
 167        .ndo_set_mac_address    = nr_set_mac_address,
 168};
 169
 170void nr_setup(struct net_device *dev)
 171{
 172        dev->mtu                = NR_MAX_PACKET_SIZE;
 173        dev->netdev_ops         = &nr_netdev_ops;
 174        dev->header_ops         = &nr_header_ops;
 175        dev->hard_header_len    = NR_NETWORK_LEN + NR_TRANSPORT_LEN;
 176        dev->addr_len           = AX25_ADDR_LEN;
 177        dev->type               = ARPHRD_NETROM;
 178
 179        /* New-style flags. */
 180        dev->flags              = IFF_NOARP;
 181}
 182