1/*
2   BNEP implementation for Linux Bluetooth stack (BlueZ).
3   Copyright (C) 2001-2002 Inventel Systemes
4   Written 2001-2002 by
5	Clément Moreau <clement.moreau@inventel.fr>
6	David Libault  <david.libault@inventel.fr>
7
8   Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
9
10   This program is free software; you can redistribute it and/or modify
11   it under the terms of the GNU General Public License version 2 as
12   published by the Free Software Foundation;
13
14   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
17   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
18   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
19   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
20   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
21   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22
23   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
24   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
25   SOFTWARE IS DISCLAIMED.
26*/
27
28#include <linux/etherdevice.h>
29
30#include <net/bluetooth/bluetooth.h>
31#include <net/bluetooth/hci_core.h>
32#include <net/bluetooth/l2cap.h>
33
34#include "bnep.h"
35
36#define BNEP_TX_QUEUE_LEN 20
37
38static int bnep_net_open(struct net_device *dev)
39{
40	netif_start_queue(dev);
41	return 0;
42}
43
44static int bnep_net_close(struct net_device *dev)
45{
46	netif_stop_queue(dev);
47	return 0;
48}
49
50static void bnep_net_set_mc_list(struct net_device *dev)
51{
52#ifdef CONFIG_BT_BNEP_MC_FILTER
53	struct bnep_session *s = netdev_priv(dev);
54	struct sock *sk = s->sock->sk;
55	struct bnep_set_filter_req *r;
56	struct sk_buff *skb;
57	int size;
58
59	BT_DBG("%s mc_count %d", dev->name, netdev_mc_count(dev));
60
61	size = sizeof(*r) + (BNEP_MAX_MULTICAST_FILTERS + 1) * ETH_ALEN * 2;
62	skb  = alloc_skb(size, GFP_ATOMIC);
63	if (!skb) {
64		BT_ERR("%s Multicast list allocation failed", dev->name);
65		return;
66	}
67
68	r = (void *) skb->data;
69	__skb_put(skb, sizeof(*r));
70
71	r->type = BNEP_CONTROL;
72	r->ctrl = BNEP_FILTER_MULTI_ADDR_SET;
73
74	if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) {
75		u8 start[ETH_ALEN] = { 0x01 };
76
77		/* Request all addresses */
78		memcpy(__skb_put(skb, ETH_ALEN), start, ETH_ALEN);
79		memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
80		r->len = htons(ETH_ALEN * 2);
81	} else {
82		struct netdev_hw_addr *ha;
83		int i, len = skb->len;
84
85		if (dev->flags & IFF_BROADCAST) {
86			memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
87			memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
88		}
89
90		/* FIXME: We should group addresses here. */
91
92		i = 0;
93		netdev_for_each_mc_addr(ha, dev) {
94			if (i == BNEP_MAX_MULTICAST_FILTERS)
95				break;
96			memcpy(__skb_put(skb, ETH_ALEN), ha->addr, ETH_ALEN);
97			memcpy(__skb_put(skb, ETH_ALEN), ha->addr, ETH_ALEN);
98
99			i++;
100		}
101		r->len = htons(skb->len - len);
102	}
103
104	skb_queue_tail(&sk->sk_write_queue, skb);
105	wake_up_interruptible(sk_sleep(sk));
106#endif
107}
108
109static int bnep_net_set_mac_addr(struct net_device *dev, void *arg)
110{
111	BT_DBG("%s", dev->name);
112	return 0;
113}
114
115static void bnep_net_timeout(struct net_device *dev)
116{
117	BT_DBG("net_timeout");
118	netif_wake_queue(dev);
119}
120
121#ifdef CONFIG_BT_BNEP_MC_FILTER
122static int bnep_net_mc_filter(struct sk_buff *skb, struct bnep_session *s)
123{
124	struct ethhdr *eh = (void *) skb->data;
125
126	if ((eh->h_dest[0] & 1) && !test_bit(bnep_mc_hash(eh->h_dest), (ulong *) &s->mc_filter))
127		return 1;
128	return 0;
129}
130#endif
131
132#ifdef CONFIG_BT_BNEP_PROTO_FILTER
133/* Determine ether protocol. Based on eth_type_trans. */
134static u16 bnep_net_eth_proto(struct sk_buff *skb)
135{
136	struct ethhdr *eh = (void *) skb->data;
137	u16 proto = ntohs(eh->h_proto);
138
139	if (proto >= ETH_P_802_3_MIN)
140		return proto;
141
142	if (get_unaligned((__be16 *) skb->data) == htons(0xFFFF))
143		return ETH_P_802_3;
144
145	return ETH_P_802_2;
146}
147
148static int bnep_net_proto_filter(struct sk_buff *skb, struct bnep_session *s)
149{
150	u16 proto = bnep_net_eth_proto(skb);
151	struct bnep_proto_filter *f = s->proto_filter;
152	int i;
153
154	for (i = 0; i < BNEP_MAX_PROTO_FILTERS && f[i].end; i++) {
155		if (proto >= f[i].start && proto <= f[i].end)
156			return 0;
157	}
158
159	BT_DBG("BNEP: filtered skb %p, proto 0x%.4x", skb, proto);
160	return 1;
161}
162#endif
163
164static netdev_tx_t bnep_net_xmit(struct sk_buff *skb,
165				 struct net_device *dev)
166{
167	struct bnep_session *s = netdev_priv(dev);
168	struct sock *sk = s->sock->sk;
169
170	BT_DBG("skb %p, dev %p", skb, dev);
171
172#ifdef CONFIG_BT_BNEP_MC_FILTER
173	if (bnep_net_mc_filter(skb, s)) {
174		kfree_skb(skb);
175		return NETDEV_TX_OK;
176	}
177#endif
178
179#ifdef CONFIG_BT_BNEP_PROTO_FILTER
180	if (bnep_net_proto_filter(skb, s)) {
181		kfree_skb(skb);
182		return NETDEV_TX_OK;
183	}
184#endif
185
186	/*
187	 * We cannot send L2CAP packets from here as we are potentially in a bh.
188	 * So we have to queue them and wake up session thread which is sleeping
189	 * on the sk_sleep(sk).
190	 */
191	dev->trans_start = jiffies;
192	skb_queue_tail(&sk->sk_write_queue, skb);
193	wake_up_interruptible(sk_sleep(sk));
194
195	if (skb_queue_len(&sk->sk_write_queue) >= BNEP_TX_QUEUE_LEN) {
196		BT_DBG("tx queue is full");
197
198		/* Stop queuing.
199		 * Session thread will do netif_wake_queue() */
200		netif_stop_queue(dev);
201	}
202
203	return NETDEV_TX_OK;
204}
205
206static const struct net_device_ops bnep_netdev_ops = {
207	.ndo_open            = bnep_net_open,
208	.ndo_stop            = bnep_net_close,
209	.ndo_start_xmit	     = bnep_net_xmit,
210	.ndo_validate_addr   = eth_validate_addr,
211	.ndo_set_rx_mode     = bnep_net_set_mc_list,
212	.ndo_set_mac_address = bnep_net_set_mac_addr,
213	.ndo_tx_timeout      = bnep_net_timeout,
214	.ndo_change_mtu	     = eth_change_mtu,
215
216};
217
218void bnep_net_setup(struct net_device *dev)
219{
220
221	eth_broadcast_addr(dev->broadcast);
222	dev->addr_len = ETH_ALEN;
223
224	ether_setup(dev);
225	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
226	dev->netdev_ops = &bnep_netdev_ops;
227
228	dev->watchdog_timeo  = HZ * 2;
229}
230