1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Generic HDLC support routines for Linux |
4 | * HDLC support |
5 | * |
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 | |
22 | static int raw_ioctl(struct net_device *dev, struct if_settings *ifs); |
23 | |
24 | static __be16 raw_type_trans(struct sk_buff *skb, struct net_device *dev) |
25 | { |
26 | return cpu_to_be16(ETH_P_IP); |
27 | } |
28 | |
29 | static struct hdlc_proto proto = { |
30 | .type_trans = raw_type_trans, |
31 | .ioctl = raw_ioctl, |
32 | .module = THIS_MODULE, |
33 | }; |
34 | |
35 | |
36 | static 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(to: raw_s, from: hdlc->state, n: 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(to: &new_settings, from: raw_s, n: 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: &proto, |
79 | size: 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(val: NETDEV_POST_TYPE_CHANGE, dev); |
85 | netif_dormant_off(dev); |
86 | return 0; |
87 | } |
88 | |
89 | return -EINVAL; |
90 | } |
91 | |
92 | |
93 | static int __init hdlc_raw_init(void) |
94 | { |
95 | register_hdlc_protocol(proto: &proto); |
96 | return 0; |
97 | } |
98 | |
99 | |
100 | |
101 | static void __exit hdlc_raw_exit(void) |
102 | { |
103 | unregister_hdlc_protocol(proto: &proto); |
104 | } |
105 | |
106 | |
107 | module_init(hdlc_raw_init); |
108 | module_exit(hdlc_raw_exit); |
109 | |
110 | MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>" ); |
111 | MODULE_DESCRIPTION("Raw HDLC protocol support for generic HDLC" ); |
112 | MODULE_LICENSE("GPL v2" ); |
113 | |