drivers/net/wan/hdlc_raw.c

   1 /*
   2  * Generic HDLC support routines for Linux
   3  * HDLC support
   4  *
   5  * Copyright (C) 1999 - 2003 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/module.h>
  13 #include <linux/kernel.h>
  14 #include <linux/slab.h>
  15 #include <linux/poll.h>
  16 #include <linux/errno.h>
  17 #include <linux/if_arp.h>
  18 #include <linux/init.h>
  19 #include <linux/skbuff.h>
  20 #include <linux/pkt_sched.h>
  21 #include <linux/inetdevice.h>
  22 #include <linux/lapb.h>
  23 #include <linux/rtnetlink.h>
  24 #include <linux/hdlc.h>
  25
  26
  27 static __be16 raw_type_trans(struct sk_buff *skb, struct net_device *dev)
  28 {
  29         return __constant_htons(ETH_P_IP);
  30 }
  31
  32
  33
  34 int hdlc_raw_ioctl(struct net_device *dev, struct ifreq *ifr)
  35 {
  36         raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
  37         const size_t size = sizeof(raw_hdlc_proto);
  38         raw_hdlc_proto new_settings;
  39         hdlc_device *hdlc = dev_to_hdlc(dev);
  40         int result;
  41
  42         switch (ifr->ifr_settings.type) {
  43         case IF_GET_PROTO:
  44                 ifr->ifr_settings.type = IF_PROTO_HDLC;
  45                 if (ifr->ifr_settings.size < size) {
  46                         ifr->ifr_settings.size = size; /* data size wanted */
  47                         return -ENOBUFS;
  48                 }
  49                 if (copy_to_user(raw_s, &hdlc->state.raw_hdlc.settings, size))
  50                         return -EFAULT;
  51                 return 0;
  52
  53         case IF_PROTO_HDLC:
  54                 if (!capable(CAP_NET_ADMIN))
  55                         return -EPERM;
  56
  57                 if (dev->flags & IFF_UP)
  58                         return -EBUSY;
  59
  60                 if (copy_from_user(&new_settings, raw_s, size))
  61                         return -EFAULT;
  62
  63                 if (new_settings.encoding == ENCODING_DEFAULT)
  64                         new_settings.encoding = ENCODING_NRZ;
  65
  66                 if (new_settings.parity == PARITY_DEFAULT)
  67                         new_settings.parity = PARITY_CRC16_PR1_CCITT;
  68
  69                 result = hdlc->attach(dev, new_settings.encoding,
  70                                       new_settings.parity);
  71                 if (result)
  72                         return result;
  73
  74                 hdlc_proto_detach(hdlc);
  75                 memcpy(&hdlc->state.raw_hdlc.settings, &new_settings, size);
  76                 memset(&hdlc->proto, 0, sizeof(hdlc->proto));
  77
  78                 hdlc->proto.type_trans = raw_type_trans;
  79                 hdlc->proto.id = IF_PROTO_HDLC;
  80                 dev->hard_start_xmit = hdlc->xmit;
  81                 dev->hard_header = NULL;
  82                 dev->type = ARPHRD_RAWHDLC;
  83                 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
  84                 dev->addr_len = 0;
  85                 return 0;
  86         }
  87
  88         return -EINVAL;
  89 }