Staging: batman-adv: receive packets directly using skbs
[safe/jmp/linux-2.6] / drivers / staging / batman-adv / soft-interface.c
1 /*
2  * Copyright (C) 2007-2009 B.A.T.M.A.N. contributors:
3  *
4  * Marek Lindner, Simon Wunderlich
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of version 2 of the GNU General Public
8  * License as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18  * 02110-1301, USA
19  *
20  */
21
22 #include "main.h"
23 #include "soft-interface.h"
24 #include "hard-interface.h"
25 #include "send.h"
26 #include "translation-table.h"
27 #include "types.h"
28 #include "hash.h"
29 #include <linux/ethtool.h>
30 #include <linux/etherdevice.h>
31 #include "compat.h"
32
33 static uint16_t bcast_seqno = 1; /* give own bcast messages seq numbers to avoid
34                                   * broadcast storms */
35 static int32_t skb_packets;
36 static int32_t skb_bad_packets;
37
38 unsigned char mainIfAddr[ETH_ALEN];
39 static unsigned char mainIfAddr_default[ETH_ALEN];
40 static int bat_get_settings(struct net_device *dev, struct ethtool_cmd *cmd);
41 static void bat_get_drvinfo(struct net_device *dev,
42                             struct ethtool_drvinfo *info);
43 static u32 bat_get_msglevel(struct net_device *dev);
44 static void bat_set_msglevel(struct net_device *dev, u32 value);
45 static u32 bat_get_link(struct net_device *dev);
46 static u32 bat_get_rx_csum(struct net_device *dev);
47 static int bat_set_rx_csum(struct net_device *dev, u32 data);
48
49 static const struct ethtool_ops bat_ethtool_ops = {
50         .get_settings = bat_get_settings,
51         .get_drvinfo = bat_get_drvinfo,
52         .get_msglevel = bat_get_msglevel,
53         .set_msglevel = bat_set_msglevel,
54         .get_link = bat_get_link,
55         .get_rx_csum = bat_get_rx_csum,
56         .set_rx_csum = bat_set_rx_csum
57 };
58
59 void set_main_if_addr(uint8_t *addr)
60 {
61         memcpy(mainIfAddr, addr, ETH_ALEN);
62 }
63
64 int main_if_was_up(void)
65 {
66         return (memcmp(mainIfAddr, mainIfAddr_default, ETH_ALEN) != 0 ? 1 : 0);
67 }
68
69 int my_skb_push(struct sk_buff *skb, unsigned int len)
70 {
71         int result = 0;
72
73         skb_packets++;
74         if (skb_headroom(skb) < len) {
75                 skb_bad_packets++;
76                 result = pskb_expand_head(skb, len, 0, GFP_ATOMIC);
77
78                 if (result < 0)
79                         return result;
80         }
81
82         skb_push(skb, len);
83         return 0;
84 }
85
86 #ifdef HAVE_NET_DEVICE_OPS
87 static const struct net_device_ops bat_netdev_ops = {
88         .ndo_open = interface_open,
89         .ndo_stop = interface_release,
90         .ndo_get_stats = interface_stats,
91         .ndo_set_mac_address = interface_set_mac_addr,
92         .ndo_change_mtu = interface_change_mtu,
93         .ndo_start_xmit = interface_tx,
94         .ndo_validate_addr = eth_validate_addr
95 };
96 #endif
97
98 void interface_setup(struct net_device *dev)
99 {
100         struct bat_priv *priv = netdev_priv(dev);
101         char dev_addr[ETH_ALEN];
102
103         ether_setup(dev);
104
105 #ifdef HAVE_NET_DEVICE_OPS
106         dev->netdev_ops = &bat_netdev_ops;
107 #else
108         dev->open = interface_open;
109         dev->stop = interface_release;
110         dev->get_stats = interface_stats;
111         dev->set_mac_address = interface_set_mac_addr;
112         dev->change_mtu = interface_change_mtu;
113         dev->hard_start_xmit = interface_tx;
114 #endif
115         dev->destructor = free_netdev;
116
117         dev->mtu = hardif_min_mtu();
118         dev->hard_header_len = BAT_HEADER_LEN; /* reserve more space in the
119                                                 * skbuff for our header */
120
121         /* generate random address */
122         random_ether_addr(dev_addr);
123         memcpy(dev->dev_addr, dev_addr, sizeof(dev->dev_addr));
124
125         SET_ETHTOOL_OPS(dev, &bat_ethtool_ops);
126
127         memset(priv, 0, sizeof(struct bat_priv));
128 }
129
130 int interface_open(struct net_device *dev)
131 {
132         netif_start_queue(dev);
133         return 0;
134 }
135
136 int interface_release(struct net_device *dev)
137 {
138         netif_stop_queue(dev);
139         return 0;
140 }
141
142 struct net_device_stats *interface_stats(struct net_device *dev)
143 {
144         struct bat_priv *priv = netdev_priv(dev);
145         return &priv->stats;
146 }
147
148 int interface_set_mac_addr(struct net_device *dev, void *addr)
149 {
150         return -EBUSY;
151 }
152
153 int interface_change_mtu(struct net_device *dev, int new_mtu)
154 {
155         /* check ranges */
156         if ((new_mtu < 68) || (new_mtu > hardif_min_mtu()))
157                 return -EINVAL;
158
159         dev->mtu = new_mtu;
160
161         return 0;
162 }
163
164 int interface_tx(struct sk_buff *skb, struct net_device *dev)
165 {
166         struct unicast_packet *unicast_packet;
167         struct bcast_packet *bcast_packet;
168         struct orig_node *orig_node;
169         struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
170         struct bat_priv *priv = netdev_priv(dev);
171         struct batman_if *batman_if;
172         uint8_t dstaddr[6];
173         int data_len = skb->len;
174         unsigned long flags;
175
176         if (atomic_read(&module_state) != MODULE_ACTIVE)
177                 goto dropped;
178
179         dev->trans_start = jiffies;
180         /* TODO: check this for locks */
181         hna_local_add(ethhdr->h_source);
182
183         /* ethernet packet should be broadcasted */
184         if (is_bcast(ethhdr->h_dest) || is_mcast(ethhdr->h_dest)) {
185
186                 if (my_skb_push(skb, sizeof(struct bcast_packet)) < 0)
187                         goto dropped;
188
189                 bcast_packet = (struct bcast_packet *)skb->data;
190                 bcast_packet->version = COMPAT_VERSION;
191
192                 /* batman packet type: broadcast */
193                 bcast_packet->packet_type = BAT_BCAST;
194
195                 /* hw address of first interface is the orig mac because only
196                  * this mac is known throughout the mesh */
197                 memcpy(bcast_packet->orig, mainIfAddr, ETH_ALEN);
198
199                 /* set broadcast sequence number */
200                 bcast_packet->seqno = htons(bcast_seqno);
201
202                 bcast_seqno++;
203
204                 /* broadcast packet */
205                 add_bcast_packet_to_list(skb);
206                 /* a copy is stored in the bcast list, therefore removing
207                  * the original skb. */
208                 kfree_skb(skb);
209
210         /* unicast packet */
211         } else {
212                 spin_lock_irqsave(&orig_hash_lock, flags);
213                 /* get routing information */
214                 orig_node = ((struct orig_node *)hash_find(orig_hash,
215                                                            ethhdr->h_dest));
216
217                 /* check for hna host */
218                 if (!orig_node)
219                         orig_node = transtable_search(ethhdr->h_dest);
220
221                 if ((orig_node) &&
222                     (orig_node->batman_if) &&
223                     (orig_node->router)) {
224                         if (my_skb_push(skb, sizeof(struct unicast_packet)) < 0)
225                                 goto unlock;
226
227                         unicast_packet = (struct unicast_packet *)skb->data;
228
229                         unicast_packet->version = COMPAT_VERSION;
230                         /* batman packet type: unicast */
231                         unicast_packet->packet_type = BAT_UNICAST;
232                         /* set unicast ttl */
233                         unicast_packet->ttl = TTL;
234                         /* copy the destination for faster routing */
235                         memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
236
237                         /* net_dev won't be available when not active */
238                         if (orig_node->batman_if->if_active != IF_ACTIVE)
239                                 goto unlock;
240
241                         /* don't lock while sending the packets ... we therefore
242                          * copy the required data before sending */
243
244                         batman_if = orig_node->batman_if;
245                         memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
246                         spin_unlock_irqrestore(&orig_hash_lock, flags);
247
248                         send_skb_packet(skb, batman_if, dstaddr);
249                 } else {
250                         goto unlock;
251                 }
252         }
253
254         priv->stats.tx_packets++;
255         priv->stats.tx_bytes += data_len;
256         goto end;
257
258 unlock:
259         spin_unlock_irqrestore(&orig_hash_lock, flags);
260 dropped:
261         priv->stats.tx_dropped++;
262 end:
263         return 0;
264 }
265
266 void interface_rx(struct sk_buff *skb, int hdr_size)
267 {
268         struct net_device *dev = soft_device;
269         struct bat_priv *priv = netdev_priv(dev);
270
271         /* check if enough space is available for pulling, and pull */
272         if (!pskb_may_pull(skb, hdr_size)) {
273                 kfree_skb(skb);
274                 return;
275         }
276         skb_pull_rcsum(skb, hdr_size);
277 /*      skb_set_mac_header(skb, -sizeof(struct ethhdr));*/
278
279         skb->dev = dev;
280         skb->protocol = eth_type_trans(skb, dev);
281
282         /* should not be neccesary anymore as we use skb_pull_rcsum()
283          * TODO: please verify this and remove this TODO
284          * -- Dec 21st 2009, Simon Wunderlich */
285
286 /*      skb->ip_summed = CHECKSUM_UNNECESSARY;*/
287
288         /* TODO: set skb->pkt_type to PACKET_BROADCAST, PACKET_MULTICAST,
289          * PACKET_OTHERHOST or PACKET_HOST */
290
291         priv->stats.rx_packets++;
292         priv->stats.rx_bytes += skb->len;
293
294         dev->last_rx = jiffies;
295
296         netif_rx(skb);
297 }
298
299 /* ethtool */
300 static int bat_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
301 {
302         cmd->supported = 0;
303         cmd->advertising = 0;
304         cmd->speed = SPEED_10;
305         cmd->duplex = DUPLEX_FULL;
306         cmd->port = PORT_TP;
307         cmd->phy_address = 0;
308         cmd->transceiver = XCVR_INTERNAL;
309         cmd->autoneg = AUTONEG_DISABLE;
310         cmd->maxtxpkt = 0;
311         cmd->maxrxpkt = 0;
312
313         return 0;
314 }
315
316 static void bat_get_drvinfo(struct net_device *dev,
317                             struct ethtool_drvinfo *info)
318 {
319         strcpy(info->driver, "B.A.T.M.A.N. advanced");
320         strcpy(info->version, SOURCE_VERSION);
321         strcpy(info->fw_version, "N/A");
322         strcpy(info->bus_info, "batman");
323 }
324
325 static u32 bat_get_msglevel(struct net_device *dev)
326 {
327         return -EOPNOTSUPP;
328 }
329
330 static void bat_set_msglevel(struct net_device *dev, u32 value)
331 {
332         return;
333 }
334
335 static u32 bat_get_link(struct net_device *dev)
336 {
337         return 1;
338 }
339
340 static u32 bat_get_rx_csum(struct net_device *dev)
341 {
342         return 0;
343 }
344
345 static int bat_set_rx_csum(struct net_device *dev, u32 data)
346 {
347         return -EOPNOTSUPP;
348 }