LXR linux/drivers/net/wan/hdlc

   1/*
   2 * Generic HDLC support routines for Linux
   3 * HDLC support
   4 *
   5 * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
   6 *
   7 * This program is free software; you can redistribute it and/or modify it
   8 * under the terms of version 2 of the GNU General Public License
   9 * as published by the Free Software Foundation.
  10 */
  11
  12#include <linux/errno.h>
  13#include <linux/hdlc.h>
  14#include <linux/if_arp.h>
  15#include <linux/inetdevice.h>
  16#include <linux/init.h>
  17#include <linux/kernel.h>
  18#include <linux/module.h>
  19#include <linux/pkt_sched.h>
  20#include <linux/poll.h>
  21#include <linux/rtnetlink.h>
  22#include <linux/skbuff.h>
  23#include <linux/slab.h>
  24
  25
  26static int raw_ioctl(struct net_device *dev, struct ifreq *ifr);
  27
  28static __be16 raw_type_trans(struct sk_buff *skb, struct net_device *dev)
  29{
  30        return cpu_to_be16(ETH_P_IP);
  31}
  32
  33static struct hdlc_proto proto = {
  34        .type_trans     = raw_type_trans,
  35        .ioctl          = raw_ioctl,
  36        .module         = THIS_MODULE,
  37};
  38
  39
  40static int raw_ioctl(struct net_device *dev, struct ifreq *ifr)
  41{
  42        raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
  43        const size_t size = sizeof(raw_hdlc_proto);
  44        raw_hdlc_proto new_settings;
  45        hdlc_device *hdlc = dev_to_hdlc(dev);
  46        int result;
  47
  48        switch (ifr->ifr_settings.type) {
  49        case IF_GET_PROTO:
  50                if (dev_to_hdlc(dev)->proto != &proto)
  51                        return -EINVAL;
  52                ifr->ifr_settings.type = IF_PROTO_HDLC;
  53                if (ifr->ifr_settings.size < size) {
  54                        ifr->ifr_settings.size = size; /* data size wanted */
  55                        return -ENOBUFS;
  56                }
  57                if (copy_to_user(raw_s, hdlc->state, size))
  58                        return -EFAULT;
  59                return 0;
  60
  61        case IF_PROTO_HDLC:
  62                if (!capable(CAP_NET_ADMIN))
  63                        return -EPERM;
  64
  65                if (dev->flags & IFF_UP)
  66                        return -EBUSY;
  67
  68                if (copy_from_user(&new_settings, raw_s, size))
  69                        return -EFAULT;
  70
  71                if (new_settings.encoding == ENCODING_DEFAULT)
  72                        new_settings.encoding = ENCODING_NRZ;
  73
  74                if (new_settings.parity == PARITY_DEFAULT)
  75                        new_settings.parity = PARITY_CRC16_PR1_CCITT;
  76
  77                result = hdlc->attach(dev, new_settings.encoding,
  78                                      new_settings.parity);
  79                if (result)
  80                        return result;
  81
  82                result = attach_hdlc_protocol(dev, &proto,
  83                                              sizeof(raw_hdlc_proto));
  84                if (result)
  85                        return result;
  86                memcpy(hdlc->state, &new_settings, size);
  87                dev->type = ARPHRD_RAWHDLC;
  88                netif_dormant_off(dev);
  89                return 0;
  90        }
  91
  92        return -EINVAL;
  93}
  94
  95
  96static int __init mod_init(void)
  97{
  98        register_hdlc_protocol(&proto);
  99        return 0;
 100}
 101
 102
 103
 104static void __exit mod_exit(void)
 105{
 106        unregister_hdlc_protocol(&proto);
 107}
 108
 109
 110module_init(mod_init);
 111module_exit(mod_exit);
 112
 113MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
 114MODULE_DESCRIPTION("Raw HDLC protocol support for generic HDLC");
 115MODULE_LICENSE("GPL v2");
 116