xref: /linux/net/bluetooth/bnep/netdev.c (revision a33f32244d8550da8b4a26e277ce07d5c6d158b5)
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/module.h>
29 #include <linux/slab.h>
30 
31 #include <linux/socket.h>
32 #include <linux/netdevice.h>
33 #include <linux/etherdevice.h>
34 #include <linux/skbuff.h>
35 #include <linux/wait.h>
36 
37 #include <asm/unaligned.h>
38 
39 #include <net/bluetooth/bluetooth.h>
40 #include <net/bluetooth/hci_core.h>
41 #include <net/bluetooth/l2cap.h>
42 
43 #include "bnep.h"
44 
45 #define BNEP_TX_QUEUE_LEN 20
46 
47 static int bnep_net_open(struct net_device *dev)
48 {
49 	netif_start_queue(dev);
50 	return 0;
51 }
52 
53 static int bnep_net_close(struct net_device *dev)
54 {
55 	netif_stop_queue(dev);
56 	return 0;
57 }
58 
59 static void bnep_net_set_mc_list(struct net_device *dev)
60 {
61 #ifdef CONFIG_BT_BNEP_MC_FILTER
62 	struct bnep_session *s = netdev_priv(dev);
63 	struct sock *sk = s->sock->sk;
64 	struct bnep_set_filter_req *r;
65 	struct sk_buff *skb;
66 	int size;
67 
68 	BT_DBG("%s mc_count %d", dev->name, netdev_mc_count(dev));
69 
70 	size = sizeof(*r) + (BNEP_MAX_MULTICAST_FILTERS + 1) * ETH_ALEN * 2;
71 	skb  = alloc_skb(size, GFP_ATOMIC);
72 	if (!skb) {
73 		BT_ERR("%s Multicast list allocation failed", dev->name);
74 		return;
75 	}
76 
77 	r = (void *) skb->data;
78 	__skb_put(skb, sizeof(*r));
79 
80 	r->type = BNEP_CONTROL;
81 	r->ctrl = BNEP_FILTER_MULTI_ADDR_SET;
82 
83 	if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) {
84 		u8 start[ETH_ALEN] = { 0x01 };
85 
86 		/* Request all addresses */
87 		memcpy(__skb_put(skb, ETH_ALEN), start, ETH_ALEN);
88 		memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
89 		r->len = htons(ETH_ALEN * 2);
90 	} else {
91 		struct dev_mc_list *dmi = dev->mc_list;
92 		int i, len = skb->len;
93 
94 		if (dev->flags & IFF_BROADCAST) {
95 			memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
96 			memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
97 		}
98 
99 		/* FIXME: We should group addresses here. */
100 
101 		for (i = 0;
102 		     i < netdev_mc_count(dev) && i < BNEP_MAX_MULTICAST_FILTERS;
103 		     i++) {
104 			memcpy(__skb_put(skb, ETH_ALEN), dmi->dmi_addr, ETH_ALEN);
105 			memcpy(__skb_put(skb, ETH_ALEN), dmi->dmi_addr, ETH_ALEN);
106 			dmi = dmi->next;
107 		}
108 		r->len = htons(skb->len - len);
109 	}
110 
111 	skb_queue_tail(&sk->sk_write_queue, skb);
112 	wake_up_interruptible(sk->sk_sleep);
113 #endif
114 }
115 
116 static int bnep_net_set_mac_addr(struct net_device *dev, void *arg)
117 {
118 	BT_DBG("%s", dev->name);
119 	return 0;
120 }
121 
122 static void bnep_net_timeout(struct net_device *dev)
123 {
124 	BT_DBG("net_timeout");
125 	netif_wake_queue(dev);
126 }
127 
128 #ifdef CONFIG_BT_BNEP_MC_FILTER
129 static inline int bnep_net_mc_filter(struct sk_buff *skb, struct bnep_session *s)
130 {
131 	struct ethhdr *eh = (void *) skb->data;
132 
133 	if ((eh->h_dest[0] & 1) && !test_bit(bnep_mc_hash(eh->h_dest), (ulong *) &s->mc_filter))
134 		return 1;
135 	return 0;
136 }
137 #endif
138 
139 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
140 /* Determine ether protocol. Based on eth_type_trans. */
141 static inline u16 bnep_net_eth_proto(struct sk_buff *skb)
142 {
143 	struct ethhdr *eh = (void *) skb->data;
144 	u16 proto = ntohs(eh->h_proto);
145 
146 	if (proto >= 1536)
147 		return proto;
148 
149 	if (get_unaligned((__be16 *) skb->data) == htons(0xFFFF))
150 		return ETH_P_802_3;
151 
152 	return ETH_P_802_2;
153 }
154 
155 static inline int bnep_net_proto_filter(struct sk_buff *skb, struct bnep_session *s)
156 {
157 	u16 proto = bnep_net_eth_proto(skb);
158 	struct bnep_proto_filter *f = s->proto_filter;
159 	int i;
160 
161 	for (i = 0; i < BNEP_MAX_PROTO_FILTERS && f[i].end; i++) {
162 		if (proto >= f[i].start && proto <= f[i].end)
163 			return 0;
164 	}
165 
166 	BT_DBG("BNEP: filtered skb %p, proto 0x%.4x", skb, proto);
167 	return 1;
168 }
169 #endif
170 
171 static netdev_tx_t bnep_net_xmit(struct sk_buff *skb,
172 				 struct net_device *dev)
173 {
174 	struct bnep_session *s = netdev_priv(dev);
175 	struct sock *sk = s->sock->sk;
176 
177 	BT_DBG("skb %p, dev %p", skb, dev);
178 
179 #ifdef CONFIG_BT_BNEP_MC_FILTER
180 	if (bnep_net_mc_filter(skb, s)) {
181 		kfree_skb(skb);
182 		return NETDEV_TX_OK;
183 	}
184 #endif
185 
186 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
187 	if (bnep_net_proto_filter(skb, s)) {
188 		kfree_skb(skb);
189 		return NETDEV_TX_OK;
190 	}
191 #endif
192 
193 	/*
194 	 * We cannot send L2CAP packets from here as we are potentially in a bh.
195 	 * So we have to queue them and wake up session thread which is sleeping
196 	 * on the sk->sk_sleep.
197 	 */
198 	dev->trans_start = jiffies;
199 	skb_queue_tail(&sk->sk_write_queue, skb);
200 	wake_up_interruptible(sk->sk_sleep);
201 
202 	if (skb_queue_len(&sk->sk_write_queue) >= BNEP_TX_QUEUE_LEN) {
203 		BT_DBG("tx queue is full");
204 
205 		/* Stop queuing.
206 		 * Session thread will do netif_wake_queue() */
207 		netif_stop_queue(dev);
208 	}
209 
210 	return NETDEV_TX_OK;
211 }
212 
213 static const struct net_device_ops bnep_netdev_ops = {
214 	.ndo_open            = bnep_net_open,
215 	.ndo_stop            = bnep_net_close,
216 	.ndo_start_xmit	     = bnep_net_xmit,
217 	.ndo_validate_addr   = eth_validate_addr,
218 	.ndo_set_multicast_list = bnep_net_set_mc_list,
219 	.ndo_set_mac_address = bnep_net_set_mac_addr,
220 	.ndo_tx_timeout      = bnep_net_timeout,
221 	.ndo_change_mtu	     = eth_change_mtu,
222 
223 };
224 
225 void bnep_net_setup(struct net_device *dev)
226 {
227 
228 	memset(dev->broadcast, 0xff, ETH_ALEN);
229 	dev->addr_len = ETH_ALEN;
230 
231 	ether_setup(dev);
232 	dev->netdev_ops = &bnep_netdev_ops;
233 
234 	dev->watchdog_timeo  = HZ * 2;
235 }
236