tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Generic HDLC support routines for Linux
3 * HDLC Ethernet emulation support
4 *
5 * Copyright (C) 2002-2003 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
29static int eth_tx(struct sk_buff *skb, struct net_device *dev)
30{
31 int pad = ETH_ZLEN - skb->len;
32 if (pad > 0) { /* Pad the frame with zeros */
33 int len = skb->len;
34 if (skb_tailroom(skb) < pad)
35 if (pskb_expand_head(skb, 0, pad, GFP_ATOMIC)) {
36 hdlc_stats(dev)->tx_dropped++;
37 dev_kfree_skb(skb);
38 return 0;
39 }
40 skb_put(skb, pad);
41 memset(skb->data + len, 0, pad);
42 }
43 return dev_to_hdlc(dev)->xmit(skb, dev);
44}
45
46
47int hdlc_raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
48{
49 raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
50 const size_t size = sizeof(raw_hdlc_proto);
51 raw_hdlc_proto new_settings;
52 hdlc_device *hdlc = dev_to_hdlc(dev);
53 int result;
54 void *old_ch_mtu;
55 int old_qlen;
56
57 switch (ifr->ifr_settings.type) {
58 case IF_GET_PROTO:
59 ifr->ifr_settings.type = IF_PROTO_HDLC_ETH;
60 if (ifr->ifr_settings.size < size) {
61 ifr->ifr_settings.size = size; /* data size wanted */
62 return -ENOBUFS;
63 }
64 if (copy_to_user(raw_s, &hdlc->state.raw_hdlc.settings, size))
65 return -EFAULT;
66 return 0;
67
68 case IF_PROTO_HDLC_ETH:
69 if (!capable(CAP_NET_ADMIN))
70 return -EPERM;
71
72 if (dev->flags & IFF_UP)
73 return -EBUSY;
74
75 if (copy_from_user(&new_settings, raw_s, size))
76 return -EFAULT;
77
78 if (new_settings.encoding == ENCODING_DEFAULT)
79 new_settings.encoding = ENCODING_NRZ;
80
81 if (new_settings.parity == PARITY_DEFAULT)
82 new_settings.parity = PARITY_CRC16_PR1_CCITT;
83
84 result = hdlc->attach(dev, new_settings.encoding,
85 new_settings.parity);
86 if (result)
87 return result;
88
89 hdlc_proto_detach(hdlc);
90 memcpy(&hdlc->state.raw_hdlc.settings, &new_settings, size);
91 memset(&hdlc->proto, 0, sizeof(hdlc->proto));
92
93 hdlc->proto.type_trans = eth_type_trans;
94 hdlc->proto.id = IF_PROTO_HDLC_ETH;
95 dev->hard_start_xmit = eth_tx;
96 old_ch_mtu = dev->change_mtu;
97 old_qlen = dev->tx_queue_len;
98 ether_setup(dev);
99 dev->change_mtu = old_ch_mtu;
100 dev->tx_queue_len = old_qlen;
101 memcpy(dev->dev_addr, "\x00\x01", 2);
102 get_random_bytes(dev->dev_addr + 2, ETH_ALEN - 2);
103 return 0;
104 }
105
106 return -EINVAL;
107}