1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Generic HDLC support routines for Linux
4*4882a593Smuzhiyun * HDLC support
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/errno.h>
10*4882a593Smuzhiyun #include <linux/hdlc.h>
11*4882a593Smuzhiyun #include <linux/if_arp.h>
12*4882a593Smuzhiyun #include <linux/inetdevice.h>
13*4882a593Smuzhiyun #include <linux/init.h>
14*4882a593Smuzhiyun #include <linux/kernel.h>
15*4882a593Smuzhiyun #include <linux/module.h>
16*4882a593Smuzhiyun #include <linux/pkt_sched.h>
17*4882a593Smuzhiyun #include <linux/poll.h>
18*4882a593Smuzhiyun #include <linux/rtnetlink.h>
19*4882a593Smuzhiyun #include <linux/skbuff.h>
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun static int raw_ioctl(struct net_device *dev, struct ifreq *ifr);
23*4882a593Smuzhiyun
raw_type_trans(struct sk_buff * skb,struct net_device * dev)24*4882a593Smuzhiyun static __be16 raw_type_trans(struct sk_buff *skb, struct net_device *dev)
25*4882a593Smuzhiyun {
26*4882a593Smuzhiyun return cpu_to_be16(ETH_P_IP);
27*4882a593Smuzhiyun }
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun static struct hdlc_proto proto = {
30*4882a593Smuzhiyun .type_trans = raw_type_trans,
31*4882a593Smuzhiyun .ioctl = raw_ioctl,
32*4882a593Smuzhiyun .module = THIS_MODULE,
33*4882a593Smuzhiyun };
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun
raw_ioctl(struct net_device * dev,struct ifreq * ifr)36*4882a593Smuzhiyun static int raw_ioctl(struct net_device *dev, struct ifreq *ifr)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
39*4882a593Smuzhiyun const size_t size = sizeof(raw_hdlc_proto);
40*4882a593Smuzhiyun raw_hdlc_proto new_settings;
41*4882a593Smuzhiyun hdlc_device *hdlc = dev_to_hdlc(dev);
42*4882a593Smuzhiyun int result;
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun switch (ifr->ifr_settings.type) {
45*4882a593Smuzhiyun case IF_GET_PROTO:
46*4882a593Smuzhiyun if (dev_to_hdlc(dev)->proto != &proto)
47*4882a593Smuzhiyun return -EINVAL;
48*4882a593Smuzhiyun ifr->ifr_settings.type = IF_PROTO_HDLC;
49*4882a593Smuzhiyun if (ifr->ifr_settings.size < size) {
50*4882a593Smuzhiyun ifr->ifr_settings.size = size; /* data size wanted */
51*4882a593Smuzhiyun return -ENOBUFS;
52*4882a593Smuzhiyun }
53*4882a593Smuzhiyun if (copy_to_user(raw_s, hdlc->state, size))
54*4882a593Smuzhiyun return -EFAULT;
55*4882a593Smuzhiyun return 0;
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun case IF_PROTO_HDLC:
58*4882a593Smuzhiyun if (!capable(CAP_NET_ADMIN))
59*4882a593Smuzhiyun return -EPERM;
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun if (dev->flags & IFF_UP)
62*4882a593Smuzhiyun return -EBUSY;
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun if (copy_from_user(&new_settings, raw_s, size))
65*4882a593Smuzhiyun return -EFAULT;
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun if (new_settings.encoding == ENCODING_DEFAULT)
68*4882a593Smuzhiyun new_settings.encoding = ENCODING_NRZ;
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun if (new_settings.parity == PARITY_DEFAULT)
71*4882a593Smuzhiyun new_settings.parity = PARITY_CRC16_PR1_CCITT;
72*4882a593Smuzhiyun
73*4882a593Smuzhiyun result = hdlc->attach(dev, new_settings.encoding,
74*4882a593Smuzhiyun new_settings.parity);
75*4882a593Smuzhiyun if (result)
76*4882a593Smuzhiyun return result;
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun result = attach_hdlc_protocol(dev, &proto,
79*4882a593Smuzhiyun sizeof(raw_hdlc_proto));
80*4882a593Smuzhiyun if (result)
81*4882a593Smuzhiyun return result;
82*4882a593Smuzhiyun memcpy(hdlc->state, &new_settings, size);
83*4882a593Smuzhiyun dev->type = ARPHRD_RAWHDLC;
84*4882a593Smuzhiyun call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
85*4882a593Smuzhiyun netif_dormant_off(dev);
86*4882a593Smuzhiyun return 0;
87*4882a593Smuzhiyun }
88*4882a593Smuzhiyun
89*4882a593Smuzhiyun return -EINVAL;
90*4882a593Smuzhiyun }
91*4882a593Smuzhiyun
92*4882a593Smuzhiyun
mod_init(void)93*4882a593Smuzhiyun static int __init mod_init(void)
94*4882a593Smuzhiyun {
95*4882a593Smuzhiyun register_hdlc_protocol(&proto);
96*4882a593Smuzhiyun return 0;
97*4882a593Smuzhiyun }
98*4882a593Smuzhiyun
99*4882a593Smuzhiyun
100*4882a593Smuzhiyun
mod_exit(void)101*4882a593Smuzhiyun static void __exit mod_exit(void)
102*4882a593Smuzhiyun {
103*4882a593Smuzhiyun unregister_hdlc_protocol(&proto);
104*4882a593Smuzhiyun }
105*4882a593Smuzhiyun
106*4882a593Smuzhiyun
107*4882a593Smuzhiyun module_init(mod_init);
108*4882a593Smuzhiyun module_exit(mod_exit);
109*4882a593Smuzhiyun
110*4882a593Smuzhiyun MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
111*4882a593Smuzhiyun MODULE_DESCRIPTION("Raw HDLC protocol support for generic HDLC");
112*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
113