blob: 11b16bdfe6aa16242e825d79d66571f5a93e0679 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Generic HDLC support routines for Linux
3 * HDLC Ethernet emulation support
4 *
Krzysztof Halasaeb2a2fd2006-09-26 23:23:45 +02005 * Copyright (C) 2002-2006 Krzysztof Halasa <khc@pm.waw.pl>
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
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/random.h>
22#include <linux/inetdevice.h>
23#include <linux/lapb.h>
24#include <linux/rtnetlink.h>
25#include <linux/etherdevice.h>
26#include <linux/hdlc.h>
27
Krzysztof Halasaeb2a2fd2006-09-26 23:23:45 +020028static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr);
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
30static int eth_tx(struct sk_buff *skb, struct net_device *dev)
31{
32 int pad = ETH_ZLEN - skb->len;
33 if (pad > 0) { /* Pad the frame with zeros */
34 int len = skb->len;
35 if (skb_tailroom(skb) < pad)
36 if (pskb_expand_head(skb, 0, pad, GFP_ATOMIC)) {
37 hdlc_stats(dev)->tx_dropped++;
38 dev_kfree_skb(skb);
39 return 0;
40 }
41 skb_put(skb, pad);
42 memset(skb->data + len, 0, pad);
43 }
44 return dev_to_hdlc(dev)->xmit(skb, dev);
45}
46
47
Krzysztof Halasaeb2a2fd2006-09-26 23:23:45 +020048static struct hdlc_proto proto = {
49 .type_trans = eth_type_trans,
50 .ioctl = raw_eth_ioctl,
51 .module = THIS_MODULE,
52};
53
54
55static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070056{
57 raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
58 const size_t size = sizeof(raw_hdlc_proto);
59 raw_hdlc_proto new_settings;
60 hdlc_device *hdlc = dev_to_hdlc(dev);
61 int result;
Al Viro904584012007-12-22 17:52:52 +000062 int (*old_ch_mtu)(struct net_device *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 int old_qlen;
64
65 switch (ifr->ifr_settings.type) {
66 case IF_GET_PROTO:
Krzysztof Halasaeb2a2fd2006-09-26 23:23:45 +020067 if (dev_to_hdlc(dev)->proto != &proto)
68 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 ifr->ifr_settings.type = IF_PROTO_HDLC_ETH;
70 if (ifr->ifr_settings.size < size) {
71 ifr->ifr_settings.size = size; /* data size wanted */
72 return -ENOBUFS;
73 }
Krzysztof Halasaeb2a2fd2006-09-26 23:23:45 +020074 if (copy_to_user(raw_s, hdlc->state, size))
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 return -EFAULT;
76 return 0;
77
78 case IF_PROTO_HDLC_ETH:
79 if (!capable(CAP_NET_ADMIN))
80 return -EPERM;
81
82 if (dev->flags & IFF_UP)
83 return -EBUSY;
84
85 if (copy_from_user(&new_settings, raw_s, size))
86 return -EFAULT;
87
88 if (new_settings.encoding == ENCODING_DEFAULT)
89 new_settings.encoding = ENCODING_NRZ;
90
91 if (new_settings.parity == PARITY_DEFAULT)
92 new_settings.parity = PARITY_CRC16_PR1_CCITT;
93
94 result = hdlc->attach(dev, new_settings.encoding,
95 new_settings.parity);
96 if (result)
97 return result;
98
Krzysztof Halasa40d25142008-02-01 22:37:12 +010099 result = attach_hdlc_protocol(dev, &proto,
Krzysztof Halasaeb2a2fd2006-09-26 23:23:45 +0200100 sizeof(raw_hdlc_proto));
101 if (result)
102 return result;
103 memcpy(hdlc->state, &new_settings, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 dev->hard_start_xmit = eth_tx;
105 old_ch_mtu = dev->change_mtu;
106 old_qlen = dev->tx_queue_len;
107 ether_setup(dev);
108 dev->change_mtu = old_ch_mtu;
109 dev->tx_queue_len = old_qlen;
110 memcpy(dev->dev_addr, "\x00\x01", 2);
111 get_random_bytes(dev->dev_addr + 2, ETH_ALEN - 2);
Krzysztof Halasa4bc83b42006-07-21 14:41:01 -0700112 netif_dormant_off(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 return 0;
114 }
115
116 return -EINVAL;
117}
Krzysztof Halasaeb2a2fd2006-09-26 23:23:45 +0200118
119
120static int __init mod_init(void)
121{
122 register_hdlc_protocol(&proto);
123 return 0;
124}
125
126
127
128static void __exit mod_exit(void)
129{
130 unregister_hdlc_protocol(&proto);
131}
132
133
134module_init(mod_init);
135module_exit(mod_exit);
136
137MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
138MODULE_DESCRIPTION("Ethernet encapsulation support for generic HDLC");
139MODULE_LICENSE("GPL v2");