]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
3 | * operating system. INET is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * Ethernet-type device handling. | |
7 | * | |
8 | * Version: @(#)eth.c 1.0.7 05/25/93 | |
9 | * | |
02c30a84 | 10 | * Authors: Ross Biro |
1da177e4 LT |
11 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
12 | * Mark Evans, <evansmp@uhura.aston.ac.uk> | |
13 | * Florian La Roche, <rzsfl@rz.uni-sb.de> | |
14 | * Alan Cox, <gw4pts@gw4pts.ampr.org> | |
15 | * | |
16 | * Fixes: | |
17 | * Mr Linux : Arp problems | |
18 | * Alan Cox : Generic queue tidyup (very tiny here) | |
19 | * Alan Cox : eth_header ntohs should be htons | |
20 | * Alan Cox : eth_rebuild_header missing an htons and | |
21 | * minor other things. | |
22 | * Tegge : Arp bug fixes. | |
23 | * Florian : Removed many unnecessary functions, code cleanup | |
24 | * and changes for new arp and skbuff. | |
25 | * Alan Cox : Redid header building to reflect new format. | |
26 | * Alan Cox : ARP only when compiled with CONFIG_INET | |
27 | * Greg Page : 802.2 and SNAP stuff. | |
28 | * Alan Cox : MAC layer pointers/new format. | |
29 | * Paul Gortmaker : eth_copy_and_sum shouldn't csum padding. | |
30 | * Alan Cox : Protect against forwarding explosions with | |
31 | * older network drivers and IFF_ALLMULTI. | |
32 | * Christer Weinigel : Better rebuild header message. | |
33 | * Andrew Morton : 26Feb01: kill ether_setup() - use netdev_boot_setup(). | |
34 | * | |
35 | * This program is free software; you can redistribute it and/or | |
36 | * modify it under the terms of the GNU General Public License | |
37 | * as published by the Free Software Foundation; either version | |
38 | * 2 of the License, or (at your option) any later version. | |
39 | */ | |
40 | #include <linux/module.h> | |
41 | #include <linux/types.h> | |
42 | #include <linux/kernel.h> | |
43 | #include <linux/sched.h> | |
44 | #include <linux/string.h> | |
45 | #include <linux/mm.h> | |
46 | #include <linux/socket.h> | |
47 | #include <linux/in.h> | |
48 | #include <linux/inet.h> | |
49 | #include <linux/ip.h> | |
50 | #include <linux/netdevice.h> | |
51 | #include <linux/etherdevice.h> | |
52 | #include <linux/skbuff.h> | |
53 | #include <linux/errno.h> | |
54 | #include <linux/config.h> | |
55 | #include <linux/init.h> | |
56 | #include <net/dst.h> | |
57 | #include <net/arp.h> | |
58 | #include <net/sock.h> | |
59 | #include <net/ipv6.h> | |
60 | #include <net/ip.h> | |
61 | #include <asm/uaccess.h> | |
62 | #include <asm/system.h> | |
63 | #include <asm/checksum.h> | |
64 | ||
65 | extern int __init netdev_boot_setup(char *str); | |
66 | ||
67 | __setup("ether=", netdev_boot_setup); | |
68 | ||
69 | /* | |
70 | * Create the Ethernet MAC header for an arbitrary protocol layer | |
71 | * | |
72 | * saddr=NULL means use device source address | |
73 | * daddr=NULL means leave destination address (eg unresolved arp) | |
74 | */ | |
75 | ||
76 | int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, | |
77 | void *daddr, void *saddr, unsigned len) | |
78 | { | |
79 | struct ethhdr *eth = (struct ethhdr *)skb_push(skb,ETH_HLEN); | |
80 | ||
81 | /* | |
82 | * Set the protocol type. For a packet of type ETH_P_802_3 we put the length | |
83 | * in here instead. It is up to the 802.2 layer to carry protocol information. | |
84 | */ | |
85 | ||
86 | if(type!=ETH_P_802_3) | |
87 | eth->h_proto = htons(type); | |
88 | else | |
89 | eth->h_proto = htons(len); | |
90 | ||
91 | /* | |
92 | * Set the source hardware address. | |
93 | */ | |
94 | ||
95 | if(saddr) | |
96 | memcpy(eth->h_source,saddr,dev->addr_len); | |
97 | else | |
98 | memcpy(eth->h_source,dev->dev_addr,dev->addr_len); | |
99 | ||
100 | /* | |
101 | * Anyway, the loopback-device should never use this function... | |
102 | */ | |
103 | ||
104 | if (dev->flags & (IFF_LOOPBACK|IFF_NOARP)) | |
105 | { | |
106 | memset(eth->h_dest, 0, dev->addr_len); | |
107 | return ETH_HLEN; | |
108 | } | |
109 | ||
110 | if(daddr) | |
111 | { | |
112 | memcpy(eth->h_dest,daddr,dev->addr_len); | |
113 | return ETH_HLEN; | |
114 | } | |
115 | ||
116 | return -ETH_HLEN; | |
117 | } | |
118 | ||
119 | ||
120 | /* | |
121 | * Rebuild the Ethernet MAC header. This is called after an ARP | |
122 | * (or in future other address resolution) has completed on this | |
123 | * sk_buff. We now let ARP fill in the other fields. | |
124 | * | |
125 | * This routine CANNOT use cached dst->neigh! | |
126 | * Really, it is used only when dst->neigh is wrong. | |
127 | */ | |
128 | ||
129 | int eth_rebuild_header(struct sk_buff *skb) | |
130 | { | |
131 | struct ethhdr *eth = (struct ethhdr *)skb->data; | |
132 | struct net_device *dev = skb->dev; | |
133 | ||
134 | switch (eth->h_proto) | |
135 | { | |
136 | #ifdef CONFIG_INET | |
137 | case __constant_htons(ETH_P_IP): | |
138 | return arp_find(eth->h_dest, skb); | |
139 | #endif | |
140 | default: | |
141 | printk(KERN_DEBUG | |
142 | "%s: unable to resolve type %X addresses.\n", | |
143 | dev->name, (int)eth->h_proto); | |
144 | ||
145 | memcpy(eth->h_source, dev->dev_addr, dev->addr_len); | |
146 | break; | |
147 | } | |
148 | ||
149 | return 0; | |
150 | } | |
151 | ||
152 | ||
153 | /* | |
154 | * Determine the packet's protocol ID. The rule here is that we | |
155 | * assume 802.3 if the type field is short enough to be a length. | |
156 | * This is normal practice and works for any 'now in use' protocol. | |
157 | */ | |
158 | ||
159 | unsigned short eth_type_trans(struct sk_buff *skb, struct net_device *dev) | |
160 | { | |
161 | struct ethhdr *eth; | |
162 | unsigned char *rawp; | |
163 | ||
164 | skb->mac.raw=skb->data; | |
165 | skb_pull(skb,ETH_HLEN); | |
166 | eth = eth_hdr(skb); | |
167 | skb->input_dev = dev; | |
168 | ||
169 | if(*eth->h_dest&1) | |
170 | { | |
171 | if(memcmp(eth->h_dest,dev->broadcast, ETH_ALEN)==0) | |
172 | skb->pkt_type=PACKET_BROADCAST; | |
173 | else | |
174 | skb->pkt_type=PACKET_MULTICAST; | |
175 | } | |
176 | ||
177 | /* | |
178 | * This ALLMULTI check should be redundant by 1.4 | |
179 | * so don't forget to remove it. | |
180 | * | |
181 | * Seems, you forgot to remove it. All silly devices | |
182 | * seems to set IFF_PROMISC. | |
183 | */ | |
184 | ||
185 | else if(1 /*dev->flags&IFF_PROMISC*/) | |
186 | { | |
187 | if(memcmp(eth->h_dest,dev->dev_addr, ETH_ALEN)) | |
188 | skb->pkt_type=PACKET_OTHERHOST; | |
189 | } | |
190 | ||
191 | if (ntohs(eth->h_proto) >= 1536) | |
192 | return eth->h_proto; | |
193 | ||
194 | rawp = skb->data; | |
195 | ||
196 | /* | |
197 | * This is a magic hack to spot IPX packets. Older Novell breaks | |
198 | * the protocol design and runs IPX over 802.3 without an 802.2 LLC | |
199 | * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This | |
200 | * won't work for fault tolerant netware but does for the rest. | |
201 | */ | |
202 | if (*(unsigned short *)rawp == 0xFFFF) | |
203 | return htons(ETH_P_802_3); | |
204 | ||
205 | /* | |
206 | * Real 802.2 LLC | |
207 | */ | |
208 | return htons(ETH_P_802_2); | |
209 | } | |
210 | ||
211 | static int eth_header_parse(struct sk_buff *skb, unsigned char *haddr) | |
212 | { | |
213 | struct ethhdr *eth = eth_hdr(skb); | |
214 | memcpy(haddr, eth->h_source, ETH_ALEN); | |
215 | return ETH_ALEN; | |
216 | } | |
217 | ||
218 | int eth_header_cache(struct neighbour *neigh, struct hh_cache *hh) | |
219 | { | |
220 | unsigned short type = hh->hh_type; | |
221 | struct ethhdr *eth; | |
222 | struct net_device *dev = neigh->dev; | |
223 | ||
224 | eth = (struct ethhdr*) | |
225 | (((u8*)hh->hh_data) + (HH_DATA_OFF(sizeof(*eth)))); | |
226 | ||
227 | if (type == __constant_htons(ETH_P_802_3)) | |
228 | return -1; | |
229 | ||
230 | eth->h_proto = type; | |
231 | memcpy(eth->h_source, dev->dev_addr, dev->addr_len); | |
232 | memcpy(eth->h_dest, neigh->ha, dev->addr_len); | |
233 | hh->hh_len = ETH_HLEN; | |
234 | return 0; | |
235 | } | |
236 | ||
237 | /* | |
238 | * Called by Address Resolution module to notify changes in address. | |
239 | */ | |
240 | ||
241 | void eth_header_cache_update(struct hh_cache *hh, struct net_device *dev, unsigned char * haddr) | |
242 | { | |
243 | memcpy(((u8*)hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)), | |
244 | haddr, dev->addr_len); | |
245 | } | |
246 | ||
247 | EXPORT_SYMBOL(eth_type_trans); | |
248 | ||
249 | static int eth_mac_addr(struct net_device *dev, void *p) | |
250 | { | |
251 | struct sockaddr *addr=p; | |
252 | if (netif_running(dev)) | |
253 | return -EBUSY; | |
254 | memcpy(dev->dev_addr, addr->sa_data,dev->addr_len); | |
255 | return 0; | |
256 | } | |
257 | ||
258 | static int eth_change_mtu(struct net_device *dev, int new_mtu) | |
259 | { | |
260 | if ((new_mtu < 68) || (new_mtu > 1500)) | |
261 | return -EINVAL; | |
262 | dev->mtu = new_mtu; | |
263 | return 0; | |
264 | } | |
265 | ||
266 | /* | |
267 | * Fill in the fields of the device structure with ethernet-generic values. | |
268 | */ | |
269 | void ether_setup(struct net_device *dev) | |
270 | { | |
271 | dev->change_mtu = eth_change_mtu; | |
272 | dev->hard_header = eth_header; | |
273 | dev->rebuild_header = eth_rebuild_header; | |
274 | dev->set_mac_address = eth_mac_addr; | |
275 | dev->hard_header_cache = eth_header_cache; | |
276 | dev->header_cache_update= eth_header_cache_update; | |
277 | dev->hard_header_parse = eth_header_parse; | |
278 | ||
279 | dev->type = ARPHRD_ETHER; | |
280 | dev->hard_header_len = ETH_HLEN; | |
281 | dev->mtu = 1500; /* eth_mtu */ | |
282 | dev->addr_len = ETH_ALEN; | |
283 | dev->tx_queue_len = 1000; /* Ethernet wants good queues */ | |
284 | dev->flags = IFF_BROADCAST|IFF_MULTICAST; | |
285 | ||
286 | memset(dev->broadcast,0xFF, ETH_ALEN); | |
287 | ||
288 | } | |
289 | EXPORT_SYMBOL(ether_setup); | |
290 | ||
291 | /** | |
292 | * alloc_etherdev - Allocates and sets up an ethernet device | |
293 | * @sizeof_priv: Size of additional driver-private structure to be allocated | |
294 | * for this ethernet device | |
295 | * | |
296 | * Fill in the fields of the device structure with ethernet-generic | |
297 | * values. Basically does everything except registering the device. | |
298 | * | |
299 | * Constructs a new net device, complete with a private data area of | |
300 | * size @sizeof_priv. A 32-byte (not bit) alignment is enforced for | |
301 | * this private data area. | |
302 | */ | |
303 | ||
304 | struct net_device *alloc_etherdev(int sizeof_priv) | |
305 | { | |
306 | return alloc_netdev(sizeof_priv, "eth%d", ether_setup); | |
307 | } | |
308 | EXPORT_SYMBOL(alloc_etherdev); |