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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Generic HDLC support routines for Linux4 * HDLC support5 *6 * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>7 */8 9#include <linux/errno.h>10#include <linux/hdlc.h>11#include <linux/if_arp.h>12#include <linux/inetdevice.h>13#include <linux/init.h>14#include <linux/kernel.h>15#include <linux/module.h>16#include <linux/pkt_sched.h>17#include <linux/poll.h>18#include <linux/rtnetlink.h>19#include <linux/skbuff.h>20 21 22static int raw_ioctl(struct net_device *dev, struct if_settings *ifs);23 24static __be16 raw_type_trans(struct sk_buff *skb, struct net_device *dev)25{26 return cpu_to_be16(ETH_P_IP);27}28 29static struct hdlc_proto proto = {30 .type_trans = raw_type_trans,31 .ioctl = raw_ioctl,32 .module = THIS_MODULE,33};34 35 36static int raw_ioctl(struct net_device *dev, struct if_settings *ifs)37{38 raw_hdlc_proto __user *raw_s = ifs->ifs_ifsu.raw_hdlc;39 const size_t size = sizeof(raw_hdlc_proto);40 raw_hdlc_proto new_settings;41 hdlc_device *hdlc = dev_to_hdlc(dev);42 int result;43 44 switch (ifs->type) {45 case IF_GET_PROTO:46 if (dev_to_hdlc(dev)->proto != &proto)47 return -EINVAL;48 ifs->type = IF_PROTO_HDLC;49 if (ifs->size < size) {50 ifs->size = size; /* data size wanted */51 return -ENOBUFS;52 }53 if (copy_to_user(raw_s, hdlc->state, size))54 return -EFAULT;55 return 0;56 57 case IF_PROTO_HDLC:58 if (!capable(CAP_NET_ADMIN))59 return -EPERM;60 61 if (dev->flags & IFF_UP)62 return -EBUSY;63 64 if (copy_from_user(&new_settings, raw_s, size))65 return -EFAULT;66 67 if (new_settings.encoding == ENCODING_DEFAULT)68 new_settings.encoding = ENCODING_NRZ;69 70 if (new_settings.parity == PARITY_DEFAULT)71 new_settings.parity = PARITY_CRC16_PR1_CCITT;72 73 result = hdlc->attach(dev, new_settings.encoding,74 new_settings.parity);75 if (result)76 return result;77 78 result = attach_hdlc_protocol(dev, &proto,79 sizeof(raw_hdlc_proto));80 if (result)81 return result;82 memcpy(hdlc->state, &new_settings, size);83 dev->type = ARPHRD_RAWHDLC;84 call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);85 netif_dormant_off(dev);86 return 0;87 }88 89 return -EINVAL;90}91 92 93static int __init hdlc_raw_init(void)94{95 register_hdlc_protocol(&proto);96 return 0;97}98 99 100 101static void __exit hdlc_raw_exit(void)102{103 unregister_hdlc_protocol(&proto);104}105 106 107module_init(hdlc_raw_init);108module_exit(hdlc_raw_exit);109 110MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");111MODULE_DESCRIPTION("Raw HDLC protocol support for generic HDLC");112MODULE_LICENSE("GPL v2");113