Merge git://git.infradead.org/~dwmw2/cafe-2.6
[linux-2.6] / drivers / net / wan / hdlc_raw_eth.c
1 /*
2  * Generic HDLC support routines for Linux
3  * HDLC Ethernet emulation support
4  *
5  * Copyright (C) 2002-2006 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/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
28 static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr);
29
30 static 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
48 static struct hdlc_proto proto = {
49         .type_trans     = eth_type_trans,
50         .ioctl          = raw_eth_ioctl,
51         .module         = THIS_MODULE,
52 };
53
54
55 static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
56 {
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;
62         void *old_ch_mtu;
63         int old_qlen;
64
65         switch (ifr->ifr_settings.type) {
66         case IF_GET_PROTO:
67                 if (dev_to_hdlc(dev)->proto != &proto)
68                         return -EINVAL;
69                 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                 }
74                 if (copy_to_user(raw_s, hdlc->state, size))
75                         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
99                 result = attach_hdlc_protocol(dev, &proto, NULL,
100                                               sizeof(raw_hdlc_proto));
101                 if (result)
102                         return result;
103                 memcpy(hdlc->state, &new_settings, size);
104                 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);
112                 netif_dormant_off(dev);
113                 return 0;
114         }
115
116         return -EINVAL;
117 }
118
119
120 static int __init mod_init(void)
121 {
122         register_hdlc_protocol(&proto);
123         return 0;
124 }
125
126
127
128 static void __exit mod_exit(void)
129 {
130         unregister_hdlc_protocol(&proto);
131 }
132
133
134 module_init(mod_init);
135 module_exit(mod_exit);
136
137 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
138 MODULE_DESCRIPTION("Ethernet encapsulation support for generic HDLC");
139 MODULE_LICENSE("GPL v2");